Functionalized lead acid battery separators, improved lead acid batteries, and related methods

Functionalized lead-acid battery separator, improved lead-acid battery, and related methods

The application is a divisional application, and the former priority date is on October 5, 2015; The former international filing date is on October 5, 2016; The former international application number is PCT/US2016/055509; The date is May 31, 2018, and the Chinese application number is 201680070325.4; the original name of the invention is "Functional lead-acid battery separator, improved lead-acid battery and related methods".

CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority and the benefit of U.S. Provisional Patent Application Serial No. 62/237,174 filed on October 5, 2015. The entire contents of the above application are incorporated herein by reference.

technical field

According to at least selected embodiments, the application or invention relates to novel, improved or optimized porous films, films or substrates, functionalized, coated or treated porous films, films or substrates, novel, improved, optimized, Functionalized, coated or treated separators, separators, multilayer separators, lead-acid battery separators or composites, including such films, membranes, substrates, separators, separators, lead-acid battery separators or composites Electrochemical devices, batteries or cells of such films, membranes, substrates, separators, separators, lead-acid battery separators or composites of new, improved or optimized plates or electrode assemblies or systems, making such Films, films, substrates, separators, separators, lead-acid battery separators, composites, systems, assemblies, battery cells, devices and/or batteries, and/or methods of using such films, films, substrates, separators, separators Plates, lead-acid battery separators, composites, systems, assemblies, battery cells, devices and/or batteries. According to at least some embodiments, the present application relates to novel, improved or optimized, functionalized, coated or treated microporous membranes, battery separators, lead-acid battery separators, separators and/or on at least one side Lead-acid battery separators having at least one functionalized, coated or treated surface, lead-acid battery separators having at least one coating, film, layer or material on at least one side, rib or surface, including such Membranes, battery separators, lead acid battery separators, separators and/or lead acid Energy storage devices, battery cells, systems, combinations, and/or batteries of battery separators, methods of making such membranes, battery separators, lead-acid battery separators, separators, and/or lead-acid battery separators, and/or use Methods of such films, battery separators, lead-acid battery separators, separators, lead-acid battery separators, composites, combinations, systems, devices, battery cells and/or batteries, and the like.

Background technique

Lead-acid battery has four basic components: positive electrode, which can be lead or lead alloy grids coated with lead oxide positive active material (PAM) coating; negative electrode, which can be coated with negative electrode active material (NAM) ) coated lead or lead alloy grid; separators; and a liquid electrolyte, usually sulfuric acid. To prevent physical contact between electrodes of opposite polarity, while allowing ion flow, an electrically insulating porous separator is placed between the electrodes. The separator typically includes a microporous polymer film or material, such as a polyolefin film, such as a polyethylene (PE) film. In lead-acid batteries, the area where the electrolyte and positive electrode meet is called the interfacial "oxidation zone." Oxidation can be purely chemical or purely electrochemical or a combination of the two. The oxidized region is on the order of hundreds of micrometers or um, extending into the electrolyte in which the separator is placed. Polyethylene and similar polymers do not have inherent oxidation resistance during cell operation, and thus accelerated oxidation may occur, especially in parts of the separator located in the oxidation zone. Oxidation of the separator material can lead to reduced battery performance and life.

[0006] A typical separator typically surrounds either or both of the positive or negative electrodes, typically in the form of an envelope, bag, or sleeve. The envelope or sleeve is obtained from a single sheet of separator material that is folded into the desired shape around the electrodes. This fold and cut

Cutting is usually carried out continuously with automated equipment. Over time, automotive battery manufacturers have reduced the thickness of the separator's back mesh from 250um to 150um, as reducing the volume of the separator allows for the presence of additional electrolyte and electrode material in the battery, improving power and performance. However, since flexural stiffness is related to the cube of thickness, even a small reduction in thickness can significantly reduce flexural stiffness. For example, a 30% reduction in thickness can result in a 70% reduction in bending stiffness. The reduced baffle stiffness presents manufacturing challenges for existing devices. For example, reduced stiffness increases the propensity for unintentional folding and creases, resulting in higher reject rates for the finished separator. Decreasing production speeds can reduce scrap rates, but the loss of productivity that accompanies such speed reductions is often not commercially desirable or feasible.

[0007] When the lead-acid battery is deeply discharged, the gravity of the electrolyte decreases as the sulfuric acid participates in the energy storage reaction. Upon recharging, a higher density of pure sulfuric acid is produced at the electrode surface (ie, the boundary layer) than the bulk electrolyte. At the boundary layer, only the outer sulfuric acid diffuses into the bulk electrolyte, while the remaining sulfuric acid accumulates at the bottom of the cell because it is heavier than the electrolyte. This separation of sulfuric acid from the bulk electrolyte is referred to as "acid stratification". The reduced level of acid at the top of the cell inhibited plate activation and increased corrosion. Also, the increase in bottom acid concentration artificially increases the voltage of the battery, which can interfere with the battery management system. Overall, acid stratification results in higher resistance, resulting in shorter battery life.

[0008] Accordingly, there is a need for improved separators and/or batteries. For example, there may be a need for improved separators or batteries that can provide improved or enhanced charge acceptance, surface conductivity, oxidation resistance, wettability, flexural stiffness and/or cycle life, and/or reduced acid content There is a need for a battery, especially a lead-acid battery, with improved charge acceptance and/or reduced acid stratification; a need for a battery separator with improved wettability, improved surface conductivity, Increased oxidation resistance and/or increased stiffness; and/or a need for a manufacturing process that allows for rapid production of battery assemblies including separators, reducing reject rates of finished separators.

SUMMARY OF THE INVENTION

According to at least selected embodiments, aspects or objects of the present application or invention, new or improved separators, batteries and/or methods can meet the above needs, and can meet the needs for improved separators that May provide improved or enhanced charge acceptance, surface conductivity, oxidation resistance, wettability, flexural stiffness and/or cycle life and/or reduced acid stratification; meeting requirements for improved batteries, especially lead-acid batteries NEED WITH ENHANCED CHARGE ACCEPTANCE AND/OR REDUCED ACID LAYERING, DEMAND FOR IMPROVED BATTERY SEPARATORS WITH IMPROVED WETTING, IMPROVED SURFACE CONDUCTIVITY, IMPROVED OXIDATION RESISTANCE, AND/OR INCREASED stiffness; and/or meet the need for improved manufacturing processes that allow rapid production of battery components including separators and reduced reject rates of finished separators, and/or may provide new and improved separators, batteries and/or methods, and/or may provide improved or enhanced charge acceptance, surface conductivity, oxidation resistance and/or cycle life, reduced acid stratification, improved abuse or contamination resistance, improved resistance to Oxidation due to metal contamination, reduced black residue, improved wettability, increased stiffness, increased separator life, or a combination thereof.

[0010] According to at least one embodiment, aspect or object of the present application or invention, oxidation of the separator is prevented to enhance, improve or maintain the desired cycle life of the battery, the useful life of the separator, or both.

[0011] In accordance with at least one embodiment, aspect or object of the present application or invention, a layer of harder material on top of the substrate may instead increase the stiffness of the baffle body, thereby avoiding a potentially hard, brittle baffle body.

[0012] According to at least specific embodiments, the battery separators described herein are directed to multilayer or composite microporous membrane battery separators that can have excellent oxidation resistance and are stable in lead-acid battery systems. According to at least other selected embodiments, the present invention relates to a battery separator having a layer that increases oxidation resistance, improves oxidation resistance in the presence of metal ion contaminants such as magnesium ions, reduces acid stratification, and improves surface conductivity, improved charge acceptance, increased stiffness and increased

Workability, and/or increase surface wettability.

[0013] According to at least some selected embodiments, the present invention relates to a separator for a battery that is a microporous polymer membrane functionalized, coated, treated, etc. to combine at least one material , treatment, function or layer is applied to at least one side thereof. In certain selected specific embodiments, the material, treatment, function, or layer may or may not include a binder, and may include one or more materials such as silica, silica, terrestrial, alumina, Metals, metal oxides, conductive carbon materials, acid stabilized cellulose, and/or the like, and/or may include one or more conductive or non-conductive or insulating layers.

[0014] According to at least some embodiments, there is provided a method of obtaining an improved separator by applying a treatment, material or layer to a polymeric microporous film, polyethylene (PE) microporous film, woven or non-woven On at least one surface or side of a woven material, nonwoven glass mat, nonwoven absorbent glass mat (AGM), nonwoven or woven PET, cellulosic nonwoven mat, and/or the like. The material, treatment or layer can be deposited by vapor deposition, chemical deposition, vacuum assisted methods, PVD, CVD, TD, DCD, PACVD, DLC, thin film coating or deposition techniques, nano thin film techniques, single atom thick coating techniques, sols - Gel, solvent coating, aqueous coating etc. application. In some embodiments, the material, treatment, coating, layer, or function is applied or added by a solvent-free method, an adhesive-free method, or a solvent-free and adhesive-free method. In other selected embodiments, the layer is applied in the presence of a binder and/or solvent, which can then be removed by post-processing.

[0015] According to at least selected embodiments, a porous membrane having a porous or ionically conductive coating or layer is provided as a battery separator in a lead-acid battery, which can improve the cycle life, start-up capability, and high charge acceptance of the battery.

[0016] According to at least certain embodiments, the battery separators described herein relate to multilayer or composite microporous membrane battery separators that can have excellent oxidation resistance and are stable in lead-acid battery systems. According to at least other selected embodiments, the present invention relates to a battery separator having a layer that increases oxidation resistance, improves oxidation resistance in the presence of metal ion contaminants such as magnesium ions, reduces acid stratification, and improves surface Electrical conductivity, improve charge acceptance, increase stiffness, runnability and machinability, and/or increase surface wettability. One method used for polymeric separators to provide oxidation resistance is through sacrificial oxidation of residual oil. During the wet formation of polyethylene (PE) separators, oils (plasticizers) such as mineral oil are used as pore formers. When residual oil remains on the separator, it may act as a sacrificial oxidizing species. Residual oil may typically be present in the separator matrix at a concentration of about 8% to 20% by weight. This reagent/oil acts as a sacrificial agent or component to oxidize before the polyethylene, thereby reducing the rate at which the separator itself is oxidized. However, after oxidation, the sacrificial oil or material may be released from the separator and may appear as a dark or black residue or film on top of the electrolyte. Additionally, a layer of anti-oxidant material may replace a few percent of the oil in the diaphragm, reducing black residue problems.

[0017] According to at least selected embodiments, aspects or objectives, the present application or invention may address the above needs or problems, and/or may provide at least one coating on at least one surface, rib, side or portion of a polymeric microporous membrane. layer, layer or material. According to at least selected embodiments, coatings, layers, films, treatments, treatments are described that impart improved oxidation resistance, reduced black residue, improved wetting, improved surface conductivity, and/or increased stiffness to separators. sediment or material. According to at least selected embodiments, batteries, particularly lead-acid batteries, are described having improved cycle life, charge acceptance, and/or reduced acid stratification.

[0018] According to at least selected embodiments, methods for preparing porous membranes having coatings, layers or materials that can impart one or more of the above-described desired properties, properties or characteristics are disclosed. In some embodiments, the coating, layer or material comprises one or more layers of electrically conductive or electrically insulating material, such as silica, iranite, metal, metal oxide, conductive carbon material, cellulose, mixtures thereof, multiple layers and/or the like.

[0019] Oxides are generally non-conductive: for example, silica, silica, island, and alumina (silica is a common term for silica, and island is a generic term for alumina).

[0020] Metals, metal oxides and carbon can all be conductive or partially conductive or semiconductive.

[0021] The separator is generally non-conductive (insulator), but porous and wetted with an electrolyte, allowing ionic conduction therethrough during charging and discharging of the battery. Some materials may be electrical insulators (do not conduct electricity), but may conduct heat (eg, rock earth).

In certain selected embodiments, the coating, layer or material is provided on the surface of the porous membrane facing the positive electrode, in other embodiments, the coating, layer or material (or a different coating, layer or material) is provided on the negative electrode-facing surface of the porous membrane. In certain embodiments, a coating, layer or material (or different coatings, layers or materials) is provided on both surfaces (or sides, top and bottom, positive and negative) of the porous membrane or separator. In some selected embodiments, the porous membrane is provided as an envelope or sleeve, and the coating, layer or material may be on the outer surface, inner surface, or both surfaces of the envelope or sleeve.

[0023] In certain selected embodiments, a layer is provided on the side, surface, rib, or portion of the microporous battery separator, such as in lead-acid batteries, which layer may preferably be resistant to oxidation (than Base film, substrate or membrane is more resistant to oxidation), present at least on the side of the separator facing the positive electrode, such as at the interface of the separator and positive electrode (or glass mat adjacent to the positive electrode or plate or PAM), in some lead-acid batteries or It may also be stable in a cell at a cell potential of at least about 2.1, 2.2, 2.5 or 2.7V (volts) or higher.

[0024] According to certain embodiments, the separators described herein relate to microporous battery separators having at least one layer or deposit comprising at least one material, such as silica, silica, terrestrial, oxide Aluminum, metals, metal oxides, conductive carbon materials, mixtures or blends thereof, etc., the thickness of the deposit or layer (or deposits and/or layers) in the range of 0.1 um to 250 um within the range. Microporous membranes in lead acid batteries having at least one layer containing silica, silica, phosphorite, alumina, metals, metal oxides, conductive carbon materials, cellulose, cellulose materials, mixtures or blends thereof , and/or the like, the separator can be made to have the same or better target properties, properties or properties as separators with residual oil coated with other materials and/or without such layers or coatings.

[0025] The coatings used herein may be inert or reactive. For example in the presence of oxygen, electrolytes, electromagnetic radiation (eg UV) or thermal energy input, reactive materials may undergo an initial reaction which results in chemical changes across or at the surface of the coating or layer. The coating, layer or material on the substrate or film may be a deposition or coating process starting material, or may be a reactive (modified) material that is or constitutes a coating or layer on the surface of the film. Also, the concentration of the desired material for the coating or layer may vary (may have a concentration or density gradient towards or away from the surface). In certain selected embodiments, a coating or layer as described herein can be very thin and contribute very little additional thickness to the overall thickness of the porous membrane or substrate, but can provide equivalently thicker oxidation-resistant porosity Oxidation resistance and/or stiffness of the membrane. In certain embodiments, a coating or layer as described herein may be a multilayer stack formed of different materials. In certain selected embodiments, the separators of the present invention contain much less processing oil than conventional separators because the coatings of the present invention reduce the need for sacrificial agents that prevent separator oxidation. In certain selected embodiments, the separator contains very little or no processing oil, or has no processing oil on the surface.

[0026] In certain selected embodiments, the coatings, layers, materials and/or the like of the present invention can increase the wettability of the separator. Conventional polyolefin separators typically have relatively hydrophobic surfaces due to the crystallinity and polymer condensation that occurs on their surfaces. In certain selected embodiments, the coating material of the present invention is a porous hydrophilic material that optionally penetrates the surface of the polymeric hydrophobic separator. See Figures 7 and 7A. However, the surface itself can be hydrophilic due to penetration of the coating material or high-energy beam or ion beam plasma (such as in physical vapor deposition (PVD)), which can embed the coating components themselves into the surface to form a gradient interface, This can facilitate better adhesion of the coating to the substrate, and/or it can form an extended interface on the porous membrane or hydrophobic surface of the substrate with better properties, such as better hydrophilicity, thereby increasing durability

Wetting rate (to water or sulfuric acid) of treated, coated or modified separators. In some cases, the infiltration occurs concurrently with the application of the coating on the porous membrane, in other embodiments, the infiltration is achieved by compression, calendering, heat treatment after the coating material or deposition has been applied to aid interfacial diffusion or other physical means. One possible coating material or component is cellulosic or cellulose, particularly or possibly preferably a cellulose coating on the positive side of the substrate or separator (the side facing the positive plate or electrode) or Material.

[0027] In at least some embodiments, the coating materials of the present invention can be electrically conductive and can provide enhanced current distribution through the polymeric microporous membrane. This enhanced distribution can be improved with active materials or PAMs such as PbO₂The electrons interact with each other, thereby increasing the rate of lead sulfate (formation) or reduction, thereby increasing the battery's ability to accept higher charge rates (i.e. improving charge acceptance). From PbO through a partially conductive insulating film (such as silica or i) on the surface of an insulating polymer film₂Ionic conduction to the separator should occur readily. Having one or more layers or coatings as an interface to reduce the barrier to ion diffusion should improve surface conductivity, charge acceptance and cycle life. The coatings or layers of the present invention can reduce the interface barrier between the positive active material (PAM) of the conductive positive plate and the insulating polymer separator or substrate. For example, consider the addition of carbon, metal, conductive or semiconducting materials on a polymer-based film or film or a silica coating or layer on a polymer-based film, substrate or film (one or more transition layers).

Various ceramic particle-containing coatings, ceramic coatings, inorganic coatings, organic coatings, inorganic and organic coatings and/or polymer coatings for microporous battery separators can provide safety, battery cycling Improvements in longevity and/or performance. Such coatings may include one or more polymers, inorganic or organic polymers or polymeric materials, polymeric binders, one or more types of inorganic or organic particles, inorganic ceramic particles, and water-based or non- water solvent. Such coatings can be applied using various techniques such as, but not limited to, PVD, CVD, sol-gel, dip coating, doctor blade, gravure printing, curtain coating, spray coating, and the like.

[0029] There is a need for improved battery separators that address some or all of the above needs, difficulties or problems. For example, there is a need for batteries, particularly lead acid batteries, with improved charge acceptance and/or reduced acid stratification. There is a need for battery separators with improved wettability, improved surface conductivity, improved oxidation resistance and/or increased stiffness. There is a need for a manufacturing process that allows rapid production of battery components including separators, reducing the reject rate of finished separators. [0030] In at least some embodiments, a coating as described herein can react with atmospheric oxygen or an electrolyte (sulfuric acid) to form a passivation layer. This passivation layer can resist oxidation and can provide an additional protective layer on the surface of the active metal (eg, aluminum) to prevent oxidation. Once the passivation layer is formed, a higher level of oxidative stability of the improved separator can be achieved. In other embodiments, the passivation layer may be obtained by subjecting the coating to thermal, UV or other energy input.

According to at least selected embodiments, the application or invention relates to novel or improved porous membranes or substrates, separators, separators, composites, electrochemical devices, batteries, the manufacture of such membranes or substrates, separators and/or Methods of batteries, and/or methods of using such films or substrates, separators, and/or batteries. In accordance with at least some embodiments, the present application relates to new or improved microporous membranes, battery separators, separators, energy storage devices including such separators, batteries, methods of making such membranes, separators and/or batteries, and /or methods of using such membranes, separators and/or batteries. According to at least some selected embodiments, the present invention relates to a separator for a battery having an oxidation protection and a binder-free deposition layer stable at at least 2.1, 2.2, 2.5 or 2.7 volts, Or even higher in some lead-acid batteries or batteries.

Description of drawings

[0032] Figure 1 is a schematic vertical cross-sectional view of a conventional positive plate and an adjacent battery separator such as a microporous PE separator separator.

Fig. 2 is the schematic vertical cross-sectional view of positive plate and functionalized separator of the present invention, and described functionalized separator is at least in porous substrate, membrane or thin film (such as microporous PE separator or membrane separator). One side (face) has at least one functional coating,

material, layer or deposition.

Figure 3 is a schematic vertical cross-sectional view of a positive plate and another functionalized separator of the present invention at least in a porous substrate, membrane or thin film (such as a microporous PE membrane separator). There are at least two functional coatings, layers, deposits and/or materials on one side. For example, Coating A can be carbon or isopyrite, and Coating B can be silica.

Figure 4 is a schematic vertical cross-sectional view of a positive plate and another functionalized separator of the present invention on each of a porous substrate, membrane or thin film (e.g., a microporous PE membrane separator). There is at least one functional coating, layer, deposition and/or material on one side. For example, Coating C can be carbon, silica, or terrestrial, and Coating D can be carbon or silica.

[0036] FIG. 5A is a table of non-limiting exemplary embodiments to be read in conjunction with the following description.

[0037] FIG. 5B is another table of non-limiting exemplary embodiments read in conjunction with the following description.

[0038] FIG. 6 is a schematic diagram of a positive plate and a separator.

[0039] Figure 7 is a schematic illustration of a coated or treated separator of the present invention having a surface coating, layer or treatment on one side.

FIG. 7A is a partially enlarged schematic view of FIG. 7, and an associated concentration plot, showing a coated or treated separator of the present invention having a surface coating or treatment on one side, the coating Or the treatment material penetrates the membrane or substrate and has a higher concentration of material in the direction facing the outer surface of the coating, layer or treatment.

Detailed ways

[0041] Embodiments of the claimed invention will now be discussed in detail. Certain terms and phrases will be used, which are well known in the art and/or are defined below.

Antioxidant one

The oxidation zone in lead-acid batteries is located at the interface between the positive electrode and the electrolyte, which can be a lead or lead alloy grid, to which a positive active material (PAM), which can be PbO, is adhered. The electrolyte can be sulfuric acid. This oxidized region is about several hundred μm and extends into the electrolyte where the separator is placed. It is obvious that if the separator is in contact with the positive electrode, the separator will be oxidized. In at least one embodiment, it is considered necessary to provide oxidation resistance as one of the preferred features of the separators of the present invention. In general, polymers are not resistant to oxidation. Disclosed herein are different methods or layers for providing oxidation resistance to polymeric separators.

Sacrificial material one in diaphragm

[0045] Polyethylene separators are the primary material used in flooded lead-acid batteries worldwide. To protect polyethylene from the oxidative attack that occurs in lead-acid batteries, residual porogens or oils remain in the separator substrate up to 8% to 20% by weight. The oil will oxidize before the polyethylene as a sacrificial material. However, after oxidation, oil is likely to be released from the separator and may appear as a black film or residue on top of the electrolyte.

Glass mat as interlayer one

[0047] A thin fiberglass mat can be attached or placed between the polymer separator and the positive electrode. The glass in lead-acid batteries is not oxidized by electrochemical potential or acid. This glass mat is in contact with the positive electrode and does not oxidize like a polymer.

The present invention adds coatings as a means to, for example, improve the oxidation resistance of PE separators, replace glass mats, or allow removal or substantial reduction of oil as porogens in addition to glass mats, thereby Minimize the possibility of black residue, reduce barriers to ion diffusion, increase surface conductivity, enhance or promote charge acceptance, reduce acid stratification, etc. The coating may include polymers, binders, particles, fibers and/or the like.

Stiffness or Workability-

[0050] In the production of automotive batteries, PE separators typically encapsulate the positive and/or negative plates. This encapsulation is done in a continuous manner with automated equipment. Traditionally, separators are not a typical failure mode for automotive batteries, so the thickness of separators has gradually decreased over the years, allowing automotive battery manufacturers to move from 250um to back mesh thicknesses as low as 150um. Since the bending stiffness is related to the cube of the thickness, reducing the thickness by 30% may result in a 70% reduction in bending stiffness, so the bending stiffness is greatly reduced, and the separator is more challenging to machine on existing equipment. This also increases the likelihood of inadvertent folds and creases, leaving more product to be scrapped on automated equipment or having to run at a significantly slower rate, which reduces productivity. Accordingly, the present invention may also provide a means to achieve thinner, increase operating speed or improve flexural stiffness, and/or provide a method of increasing the flexural stiffness of a separator, or any combination thereof.

Surface conductivity-

[0052] Current is fed into the active material (PAM or NAM) through the positive or negative gate. As is known, the active material extends either vertically, horizontally or laterally to the grid, or even to the depth of the electrode and occupies a different distance from the grid. Therefore, the conversion of the active material is not uniform, but may be a function of the distance from the current collector. Therefore, the idea is to make the surface of the separator or associated laminate conductive so that electrons will have alternative paths to flow and react with the active material. The extent to which this can be achieved reflects a more efficient use of active materials in energy storage reactions, both in terms of conversion rate and availability. Accordingly, described herein are means and methods for improving the charge acceptance of batteries through improvements to the separator.

Acid layering one

[0054] When a lead-acid battery is deeply discharged, the gravity of the electrolyte will drop because sulfuric acid is also a participant in the energy storage reaction. Upon recharging, pure sulfuric acid will be produced on the electrode surface, which is gravitationally heavier than the bulk electrolyte. Since this sulfuric acid boundary layer is created at the electrode surface, it will create a boundary layer in which only the outer layer of sulfuric acid diffuses into the bulk electrolyte, while the remaining boundary layer will be gravitationally acted upon and accumulate at the bottom of the cell. As the battery is overcharged, air bubbles will nucleate and rise to the top of the battery, bringing some sulfuric acid to the top, creating a mixing effect within the battery to at least partially overcome acid stratification. If the battery is not fully charged, the layered acid will adversely affect the electrochemical performance of the battery in the future because it is located inside the battery, but not in the correct location, or is not properly dispersed to react with the active species as a whole. Accordingly, embodiments of the present invention provide a means and/or method for reducing or destroying boundary acid generation at electrode surfaces, and/or allowing acid mixing, and/or preventing acid without overcharging and synthesis gas evolution Layered.

Improved separator wettability-

[0056] It has been found that the surface of PE separators is generally somewhat hydrophobic because PE separators have a polymer-rich surface due to crystallinity and the nature of polymer condensation. This polymer-rich layer may be only a few micrometers thick, and once it is infiltrated, the underlying highly porous separator matrix is sufficiently hydrophilic. Due to this condition, hydrophilic surfactants are often applied to the separator surface or substrate to overcome this condition. In preferred embodiments, means and/or alternative methods for wetting the surface of the separator substrate are provided.

All of the above-mentioned embodiments of the present invention have one thing in common, namely forming, coating or depositing on the surface of the separator, or laminating one (or multiple layers) of functional materials to reinforce the separator and place the separator battery performance, increase battery productivity, etc., and any combination of them. Thus, it has been unexpectedly discovered that various functional materials can be applied to lead-acid battery separators adjacent to PAM, NAM, or both by vapor deposition, chemical deposition, solvent coating, aqueous coating, and various combinations, using or Glass mats are not used. In certain embodiments, it is preferred that the layer or layers added may be in the range of 0.1 um to 250 um, with about 5 um to about 75 um per layer or combination being preferred.

[0058] The coating may be a mixture of fibers (eg, glass fibers) and particles (eg, silica), wherein the glass fibers are resistant to acid delamination in addition to oxidation. This can be achieved by coating a mixture of sol-gel materials containing glass fibers, silica and a binder

This is achieved by dispersing the dispersion medium or solvent by radiation or spraying, and then drying the dispersion medium (eg water). The adhesive bonds the composite material together and to the substrate.

Antioxidant and Black Residue -

[0060] Since the deposited silica is inherently porous in structure and inert to the oxidative attack that can occur in lead-acid batteries, it is suggested to deposit a thin layer of silica on the surface of the separator or polymer film or substrate. It may be preferred that the silica is deposited in such a way that the resulting substructure remains porous and inherently adheres to the separator surface.

[0061] In application, the backing mesh, ribs and/or substrate may inadvertently come into contact with the positive electrode. During charging, especially during overcharging, nascent oxygen or oxidizing species are generated on the electrode surface. When they come into contact with the separator, the exposed polymer separator surfaces may be oxidized, especially the polymers that bind the separator components together. Given enough time, these oxidizing species could actually create splits and cracks in the separator, which could eventually lead to an electron conduction path between the positive and negative electrodes, which could short-circuit the battery.

[0062] Due to the silica anti-oxidation layer on the surface of the separator, many functions can be produced. First, the residual porogen or oil may be greatly reduced since it is no longer needed to protect the polymer, since that function has been switched to the silica layer. With a reduced presence of residual porogens in the separator, the tendency for black residues may be reduced. With increased oxidation resistance, the substrate or backing web thickness can be further reduced without fear of failure due to oxidation, cracking, splitting, tearing, or any combination thereof.

Stiffness, runnability and machinability-

[0064] The bulk of the lead-acid battery separator is a three-dimensional structure comprising a substrate or back mesh of a given thickness and a three-dimensional shape, such as continuous trapezoids or ribs protruding from the surface of the substrate. Due to this arrangement, the lowest bending resistance is found in the direction perpendicular to the ribs. Since separators are typically sold in rolls, if very thin, they may easily fold, wrinkle, or become skewed due to the width of the separator or substrate deformation in the transverse direction (CMD). One way to improve the flexural resistance or stiffness of CMDs is to deposit low flexural or semi-rigid materials. One embodiment deposits a layer of carbon or silica, and the resulting network will not bend easily, but is actually substantially rigid. This stiffness can be enhanced by the degree of packing of the individual particles and the thickness of the layer or layers deposited on the substrate.

A possibly preferred embodiment is to deposit a continuous hardened layer on either side (or both sides) of the separator, regardless of whether the coating faces the negative or positive electrode. Stiffness can be enhanced even if the layers of these materials are not deposited as continuous layers but as exfoliated or cross-hatched.

Improved Separator Wetting-

[0067] In order to improve the wettability of the separator in the absence of surfactants, it is proposed to deposit a thin layer of highly porous silica on the surface of the separator. The deposited silica may require some additional calendering force to actually penetrate the polymer rich layer to improve the wetting rate of the separator.

Surface conductivity-

In order to improve the surface conductivity, it is foreseeable to deposit carbon structures (such as graphite, graphene, carbon, CNTs, etc.) with sufficient conductivity on the negative electrode facing surface of the separator, or the positive electrode facing surface. Ribs, or laminates, or AGM separators in direct contact with the positive plates. When a lead-acid battery is discharged, a layer of lead sulfate forms on the surface of the electrode, which is fairly non-conductive relative to the surrounding lead. Since the above material with a conductive layer will be in contact with the electrodes, this will allow any surface charge to be transported via the conductive paths now found on the separator and thus reduce the sulfate layer in a more efficient manner. It is important to note here that the path of conductance is created mainly in the X and y planes of the separator and not completely through the Z plane. If the electronic conductivity were achieved through the Z-plane, there would be electronic conductance and the separator would stop performing its function as this would short out the battery. By creating alternative conductance paths in the X and Y planes, it is foreseeable to increase the rate of lead sulfate reduction, from

The ability to receive higher rates of charge is improved, which is often referred to as charge acceptance.

[0070] Such conductive layers can also be applied to rib or laminate structures such as stickers, retention pads, AGM separators, or gauntlets, all of which are in intimate contact with the positive electrode. Since the positive active material on the plate switches at different rates, depending on the distance from the current collector source, some parts of the plate will quickly fully charge into the outgassing, while other parts of the active material will remain charged and require more current. Therefore, as outgassing begins, a portion of the current may be wasted and lead to higher positive grid corrosion rates. By providing an alternative path for current distribution to the positive grid, current crowding is eliminated and switching becomes more efficient, resulting in less gas emissions and lower grid corrosion rates. Alternative paths for these current distributions come from conductive layers, such as carbon structures, which are now on separator ribs, AGM separators, or laminate structures in direct contact with the positive electrode. When forming the battery, the conductive material can easily contact the positive electrode slurry (PAM), thereby enhancing the conductive path and reducing or eliminating the interface barrier between the separator and the positive electrode slurry (positive plate).

Acid layering one

[0072] To prevent acid delamination, the sulfuric acid boundary layer formed on the positive and negative plates may be destroyed during charging. Therefore, it is expected that no matter what material is in contact with the plate surface (negative or positive), a thin layer of porous silica will be deposited. Since the silica layer is inherently porous and has a very high surface area, the acid will diffuse quickly, making it easy to mix with most acids. Since this silica layer can be in direct contact with the plate surface, it will also serve to mechanically interrupt the laminar flow at the boundary of the acid, which is primarily gravitational.

Thus, it is envisioned that the silica layer may be deposited on the surface of the separator, or on ribs, AGM, laminate structures in direct contact with the plate (e.g. stickers), retention pads or drains, or any combination thereof.

The material, treatment or layer may be applied by vapor deposition, chemical deposition, vacuum assisted methods, PVD, CVD, TD, DCD, PACVD, DLC, thin film coating or deposition techniques, nanofilm techniques, monolithic Atom thick coating techniques, sol-gel, solvent coating, aqueous coating, etc., or any combination thereof. E.g:

PVD: Physical Vapor Deposition-the use of a high-energy beam to remove atoms from a metal or alloy or composite target and deposit it on a surface of interest. Atoms escape the target surface as ionized vapors. Various energy sources such as electron beam, thermal energy, surface resistance heating, pulsed laser, plasma discharge are possible. All of these methods are vacuum assisted.

CVD: Chemical Vapor Deposition-Reactive precursors containing material to be deposited in some chemical form react or decompose on a substrate surface and form a deposit. Volatile by-products of precursor decomposition or reaction will be pumped out of the deposition chamber. Precursors are gaseous substances that are chemically engineered to form deposits of suitable chemical properties on a surface. Unwanted parts of the precursor leave the chamber. Depending on the chamber pressure, the CVD methods are referred to as atmospheric pressure (APCVD), low pressure (LPCVD) and ultra-high vacuum (UHVCVD). Plasma enhancement (PACVD) uses plasma to enhance the reaction of precursors. Other variations to suit deposition needs are also possible.

[0077] DCD: Dynamic Compound Deposition - A coating is formed by a low temperature process that forms a dry film on the surface. The deposition is based on the principles of in situ mechanical activation and surface chemical transformation. This can be assisted by PVD or CVD or a combination thereof. Micro and macro structures can be developed on the surface using this process. One can envisage the formation of just the ribs or the formation of a coating over the entire surface by this process.

Thermal or thermal reactive deposition (TD) is a high temperature deposition process for the production of high temperature stable materials such as oxides, carbides, etc. -++*

Σ Art 0

[0079] DLC is diamond-like carbon. Diamond-like carbon is an insulating or dielectric material.

[0080] Of the many sets of properties required for a separator, some are bulk and others are surface properties. At least selected embodiments of the present invention may satisfy surface-dependent properties at the surface, and in doing so, may reduce body requirements or cost. For example, oxidation resistance is required on the surface in contact with the positive plate, so we can reduce the oxidation resistance throughout the bulk

point. Furthermore, properties such as surface conductivity, resistance to oxidation, reduced acid stratification, improved wettability, etc. are desirable for the surface, so we can target these properties to the surface, eg, by coating.

Surface coatings comprising polar materials such as silica, phosphorite, etc. can be provided by any method such as chemical vapor deposition, atomic layer deposition (ALD), sol-gel coating, radiation coating, etc. to reduce acid stratification. It can improve the required properties, improve the oxidation resistance, improve the wettability, and improve the surface ionic conductivity, etc. Using these methods it is possible to achieve precise thicknesses to the desired or desired level. High purity can also be achieved by these methods.

[0082] By having carbon or any other conducting or semiconducting layer or a combination of conducting and polar layers (eg, silica and carbon together), improved charge acceptance can be expected.

[0083] The vapor deposition process is a vacuum or low pressure assisted process. The presence of oil in the separator may cause the coating to foam, as oil tends to seep out of the pores in a vacuum. This problem is eliminated by dry films coated with the layers of the present invention. Also, the adhesion of this layer to the substrate may not be a big problem since the separator also contains silica which helps to bond the polar oxide coating to the substrate.

Advantages of at least some embodiments of the present invention:

1. Providing the required functionality through the surface layer helps to isolate and solve problems in a variety of ways.

2. improving surface performance can not only improve the performance of separator, but also improve the charge-discharge performance of battery, charge acceptance etc.

3. Numerous coating methods and materials are possible. It is even possible to radiate using a small amount of binder to coat the surface of the separator with glass fibers, cellulose fibers, carbon fibers, conductive carbon fibers, etc. This can be applied in the form of ribs using a screen printing method through a mask.

Non-limiting example

a. Both sides are coated with the same material

[0090] The polymeric substrate may be coated on both sides with a conductive carbon coating applied by radiation coating. The desired coating thickness can be from about 1 um to about 20 um. This could improve the surface conductivity of the surfaces of batteries built with this separator, reduce current crowding, improve current distribution, and increase charge acceptance. Carbon is porous and can also provide acid retention at both electrodes to reduce acid stratification.

b. Different coatings on each side, for example: Alumina on the positive side and Silica on the negative side

[0092] Aluminum can be deposited on the separator by physical vapor deposition in the presence of oxygen. Due to the presence of plasma and oxygen, the aluminum on the surface of the substrate becomes aluminum oxide and deposits on the surface. The thickness of the coating is preferably about 2 um to about 10 um. Species are highly polar, which will reduce the barriers to ion diffusion at the positive interface between the electrode and separator. The rocky soil is porous, which reduces acid stratification. Species may also potentially lock (bond) metal ions, such as Sb, Cr, Ni, Mn, etc., which are detrimental to the performance of lead-acid batteries. The silica on the negative side can be deposited by a sol-gel method with silica coagulated in a small amount of polymer binder (eg, acrylic). Radiation coating can also be used to obtain uniform thin layers preferably on the order of about 1 um to about 20 um or more. The high surface area of silica and isotopes can potentially prevent the migration of harmful ions, reduce acid delamination and increase the stiffness and puncture resistance of the films. The isopyrite provides oxidation resistance on the positive side. Thus, the polymer separator can have less oil, which is a sacrificial oxidizing medium in the polyethylene separator, which in turn can reduce the tendency to form black residues, reduce costs, and the like.

c. Two or more coatings

Three or more layers: carbon (sprayed)/arborite (reactive PVD)/silica (sol-gel)/separator/carbon (sprayed), from the side facing the positive to negative plates

[0095] A method similar to that described above can be employed. Silica may preferably be first coated on one side of the separator. Then put the

The soil is deposited on top of the silica. Carbon is then deposited on both sides. This enables both sides to have surface conductivity and hydrophilicity from the iso-earth and silica. Arborite and silica provide oxidation resistance to the polymer separator.

d. Gradient coating (high carbon content on the coating surface, high alumina content near the base film coating): carbon/asphalt-carbon composite/partition

[0097] The separator can be first coated with phosphorite in oxygen using reactive physical vapor deposition to reach about 2 um to about 4 um. The target was changed to an Al-C composite target, which when sputtered produces different carbon loadings in the rock. This provides a low carbon concentration gradient near the separator. The uppermost carbon layer is deposited by CVD. By doing this, the concentration gradient of carbon reaches 100% carbon on the surface and about 50% carbon in the intermediate region to about 0% carbon near the surface of the PE separator. By doing so, ionic conductivity can be prolonged, higher porosity can be achieved to trap contaminants such as Cr, Mn, etc., and the need for oil to reduce black residue is reduced.

e. Possible two-layer coating: carbon on sand on top of separator.

[0099] The carbon is coated by CVD or radiation. Advantages: Surface conduction, anti-oxidation, reduced acid stratification, improved charge acceptance.

[0100] Phosphate obtained by reactive PVD: increases the diffusion of ions through the separator. Reduce the migration of harmful ions such as Cr, Sb, Mn from the positive electrode to the negative electrode.

f. Possible gradient coatings

[0102] A carbon gradient is preferred because it provides electrical conductivity.

[0103] A pectite coating is also preferred because of its high oxidation resistance.

g. Possible positive plate side coating

[0105] Preferred positive side coatings are materials that provide high oxidation resistance in deep cycle liquid-charged lead-acid batteries. Conductive carbon provides high surface conduction in starting, lighting, ignition (SLI) batteries, providing high cold cranking current (CCA) and dynamic charge acceptance.

h. Possible negative plate side coating

[0107] The negative side of the separator is not oxidized. However, the presence of an overlying porous coating reduces acid delamination. Carbon provides improved interfacial conduction on the negative side and can increase capacity.

i. Other possible preferred examples

[0109] Nafion coatings (fluoropolymer copolymers based on sulfonated tetrafluoroethylene) or polytetrafluoroethylene (PTFE) that can be used in flow batteries prevent the diffusion of vanadium, magnesium, iron, etc. This property is very important for lead-acid batteries that may be plagued by elements such as antimony (the positive grid is made of Pb-Sb that provides deep cycling performance), magnesium that may come from supplementary acid in dry cells, iron in silica used in PE separators, etc. very useful. These elements are electrochemically active at the potential state of lead-acid batteries and may cause separator oxidation (Cr, Fe) or increased hydrogen evolution (Sb) due to reduced hydrogen overvoltage of antimony deposited on the negative plate. Nafion may prevent the diffusion of these ionic species. Thin coatings of about 2 um to about 10 um thickness are believed to provide the desired barrier properties for the diffusion of these ions. If this material is deposited on top of an AGM, it opens up new possibilities for using AGM-type separators in antimony-containing systems. It is expected that similar functionality could come from materials such as polyethylene oxide having sulfonic acid side chains or other complexing groups as side chains.

j. Cellulosic separators or paper separators are commonly used in dry cells

[0111] Such separators generally consist of four basic components: cellulosic fibers, phenol formaldehyde resins (novolacs), wetting agents, and cellulosic binders. Cellulose imparts antioxidant properties during battery formation and function. The PE separator of the present invention can be coated with a layer of about 1 to 20 um of cellulose-binder mixture. The surface layer will impart the desired oxidation resistance to the PE separator in Cr or other metal-containing environments such as those found in dry cells.

k. Possible coatings for battery cases, plates, glass mats, viewing devices and/or separators

[0113] A thin layer of glass fiber with a small amount of organic binder (less than about 1%) can be deposited on top of the PE separator by spraying or radiation coating, or the like. The entire assembly is cured to form a thin fiberglass layer on top of the separator. Glass fibers are very resistant to oxidation and provide capillary forces to maintain acidity and prevent acid stratification.

Microporous Membranes

The separator of the present invention preferably comprises a porous substrate or membrane (such as a microporous membrane, mesoporous or macroporous membrane having pores less than about 1 μm,₁n), made of natural or synthetic materials such as polyolefins, polyethylene, polypropylene, phenolic resins, PVC, rubber, synthetic wood pulp (SWP), glass fibers, cellulose fibers, or combinations thereof, and more Microporous membranes made of thermoplastic polymers are preferred. Preferred microporous membranes can have a pore diameter of about 0.1 μή (100 nm) or less and a porosity of about 60%. In principle, the polymer can include all acid-resistant thermoplastic materials suitable for use in lead-acid batteries. Preferred thermoplastic polymers include polyethylene and polyolefins. The polyethylene-based material includes, for example, polyvinyl chloride (PVC). The polyolefins include, for example, polyethylene, ultra-high molecular weight polyethylene (UHMWPE), and polypropylene. A preferred embodiment may include UHMWPE and filler. In general, preferred separators can be made by mixing UHMWPE and process oil in an extruder filler. In some embodiments, a preferred separator can be prepared by mixing about 30 wt% filler with about 10 wt% UHMWPE and about 60% process oil in an extruder. In other embodiments, the filler content is higher, such as about 50%, 60%, 70%, or 80% by weight. In other selected embodiments, the processing oil is present in an amount of no more than 60%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, or 10% by weight Heavy quantity%. The mixture may also contain traces of other additives or agents commonly found in the separator field (eg, wetting agents, colorants, antistatic additives, etc.) and extruded into sheets.

The microporous separator layer is preferably made of a polyolefin such as polypropylene, ethylene-butene copolymer, polyethylene-polybutadiene copolymer, polyethylene-polyisoprene copolymer, preferably Polyethylene, more preferably high molecular weight polyethylene, i.e. polyethylene having a molecular weight of at least 600,000, even more preferably ultra-high molecular weight polyethylene, i.e.: having at least 1,000,000, especially more than 4,000,000, and most preferably 5,000,000 to 8,000,000 (by viscometry Molecular weight measured and calculated by Margolie's equation), a standard load melt index of substantially 0 (according to ASTM D 1238 (Condition E), using a standard load of 2,160 g) and a viscosity value of not less than 600 ml/g, preferably not less than 1000 ml/g, More preferably not less than 2,000 ml/g, and most preferably not less than 3,000 ml/g (measured at 130°C in a solution of 0.02 g of polyolefin in 100 g of decalin) polyethylene.

[0117] According to at least one embodiment, the separator is made of ultra high molecular weight polyethylene (UHMWPE) mixed with process oil and filler. According to at least one other embodiment, the separator is composed of ultra high molecular weight polyethylene (UHMWPE) mixed with treatment oil, additives and talc. The microporous polymer layer preferably comprises a homogeneous mixture of 8 to 100 vol% polyolefin, 0-40 vol% plasticizer and 0 to 92 vol% inert filler material. The preferred filler is talc. Preferred plasticizers are petroleum oils. Since plasticizer is the easiest component to remove from polymer-filler-plasticizer compositions, it can be used to impart porosity to battery separators.

[0118] In certain embodiments, residual process oil can be removed after extrusion by conventional methods such as solvent washing, ovens, and the like. In certain selected embodiments, the final amount of processing oil present in the extruded polymer does not exceed 20%, 18%, 16%, 14%, 12%, 10%, 9%, 8%, 7% , 6%, 5%, 4%, 3%, 2%, 1% or 0.5%.

[0119] In some cases, the preferred filler is dry finely divided silica. However, the filler may be selected from silica, fumed silica, mica, montmorillonite, kaolinite, asbestos, talc, diatomaceous earth, vermiculite, natural and synthetic zeolites, cement, calcium silicates, clays, aluminum silicates , sodium aluminosilicate, polyaluminosilicate, alumina silica gel, glass particles, carbon black, activated carbon, carbon fiber, conductive carbon fiber

fiber, other conductive fibers, cellulose fibers, charcoal, graphite, titanium oxide, iron oxide, copper oxide, zinc oxide, lead oxide, bustard, antimony oxide, zirconium oxide, magnesium oxide, aluminum oxide, aluminum disulfide, zinc sulfide, Sulfate collar, strontium sulfate, calcium carbonate, magnesium carbonate, etc., and various combinations thereof. For example, organic solvents can be used to coat thin layers of fumed silica and potentially eliminate acid stratification and provide oxidation resistance. The thin layer of pyrogenic silica may include carbon or other materials. For example, infiltrating fumed silica with cellulose fibers and binders as a thin film on top of a PE membrane can hold the fumed silica in place. Also, a thin layer of fumed silica can be applied on one side and a layer of carbon can be applied on the other side, or a thin layer of carbon can be applied on a thin layer of fumed silica.

[0120] The porous membranes used in the various embodiments herein may be provided with one or more additives or agents. One such additive that may be present in polyolefins is a surfactant. Suitable surfactants include surfactants such as: alkyl sulfates; alkylarylsulfonates; alkylphenol-alkylene oxide addition products; soaps; alkyl-naphthalenesulfonates; sulfosuccinates dialkyl esters; quaternary amines; block copolymers of ethylene oxide and propylene oxide; and salts of monoalkyl phosphates and dialkyl phosphates. The additive may be a nonionic surfactant such as polyol fatty acid esters, polyethoxylated esters, polyethoxylated fatty alcohols, alkyl polysaccharides such as alkyl polysaccharides and mixtures thereof, amine ethoxylates , sorbitol tincture fatty acid ester ethoxylates, organosiloxane based surfactants, ethylene vinyl acetate terpolymers, ethoxylated alkyl aryl phosphates and sucrose esters of fatty acids.

In certain embodiments, the additive can be represented by a compound of formula (I)

R(OR¹)n(COOM^x+1/x)_m(I)

wherein,

R is a non-aromatic hydrocarbon group having 10 to 4200 carbon atoms, preferably 13 to 4200 carbon atoms, which may be interrupted by oxygen atoms,

R¹is H, - (CH2)kCOOM^x+1/x or -(CH₂)_k-SO₃M^X+_1/X, preferably H, where k is 1 or 2,

M is an alkali metal or alkaline earth metal ion, H⁺or NH₄⁺, where not all variables M have H at the same time⁺base,

n is 0 or 1,

m is 0 or an integer from 10 to 1400, and

x is 1 or 2,

The ratio of oxygen atom to carbon atom in the compound of formula (I) is in the range of 1:1.5 to 1:30, and m and n cannot be simultaneously

0. However, it is preferred that only one variable of n and m is not equal to 0.

[0131] A non-aromatic hydrocarbon group refers to a group that does not contain an aromatic group or that itself represents one. Hydrocarbyl groups can be interrupted by oxygen atoms, ie contain one or more ether groups.

R is preferably a straight or branched chain aliphatic hydrocarbon group which may be interrupted by oxygen atoms. Saturated, uncrosslinked hydrocarbon groups are very particularly preferred.

[0133] The additives of the compounds of formula (I) used in the production of the various porous membranes described herein can also provide effective protection against oxidative damage to such separators. In some embodiments, porous membranes are preferred comprising additives comprising compounds according to formula (I), wherein

R is a hydrocarbon group having 10-180, preferably 12-75 and very particularly preferably 14-40 carbon atoms, which may be interrupted by 160, preferably 1-20 and very particularly preferably 1-8 oxygen atoms , especially preferred formula R²- [ (OC₂H₄) _p (OC₃H₆) _q]-hydrocarbyl, where

[0135].R²is an alkyl group having 10 to 30 carbon atoms, preferably 12 to 25, particularly preferably 14 to 20 carbon atoms,

p is an integer from 0 to 30, preferably 0 to 10, particularly preferably 0 to 4, and

q is an integer from 0 to 30, preferably 0 to 10, particularly preferably 0 to 4,

the sum of p and q in particularly preferred compounds is from 0 to 10, especially from 0 to 4,

n is 1, and

[0140] m is 0.

Formula R²- [(OC₂H₄） _p (OC₃H₆） _q] - should be understood to also include compounds in which the sequences of groups within square brackets differ from those shown. For example according to the invention compounds in which the groups in parentheses are formed by exchanging the (OC2H4) and (OC3H6) groups are suitable.

wherein R²Additives which are straight-chain or branched-chain alkyl groups having 10 to 20, preferably 14 to 18, carbon atoms have proven to be particularly advantageous. OC₂H₄Preferably represents OCH₂cH₂,OC₃H₆stands for OCH (CH3) CH₂and/or OCH₂cH (CH3).

Proposed as preferred additives are particularly preferred alcohols (p=q=0; m=0) primary alcohols, preferably fatty alcohol ethoxylates (p=1 to 4; q=0), fatty alcohol propylene Primary alcohols of oxygenates (p = 0; q = 1 to 4) and fatty alcohol alkoxylates (p = 1 to 2; q = 1 to 4). Fatty alcohol alkoxylates are obtainable, for example, by reaction of the corresponding alcohols with ethylene oxide or propylene oxide.

[0144] Additives of the m=0 type that are insoluble or poorly soluble in water and sulfuric acid have proven to be particularly advantageous.

Also preferred are additives containing compounds according to formula (I), wherein,

R is an alkane radical having 20 to 4200, preferably 50 to 750 and very particularly preferably 80 to 225 carbon atoms,

m is an alkali metal or alkaline earth metal ion, H⁺or NH⁴⁺, especially alkali metal ions such as Li⁺, Na⁺and K⁺or H⁺, where not all variables M have H at the same time⁺base,

n is 0,

m is an integer from 10 to 1400

x is 1 or 2.

[0151] Particular mention here as suitable additives are polyacrylic acids, polymethacrylic acids and acrylic acid-methacrylic acid copolymers in which the acid groups are at least partially (preferably 40%, particularly preferably 80%) neutralized. The percentages refer to the number of acid groups. Very particular preference is given to poly(meth)acrylic acid which is present entirely in salt form. Poly(meth)acrylic acid refers to polyacrylic acid, polymethacrylic acid and acrylic-methacrylic acid copolymers. Poly(meth)acrylic acid is preferred, especially polyacrylic acid having an average molar mass Mw of from 1,000 to 100,000 g/mol, particularly preferably from 1,000 to 15,000 g/mol and very particularly preferably from 1,000 to 4,000 g/mol. The molecular weight of poly(meth)acrylic acid polymers and copolymers was determined by measuring the viscosity of a 1% aqueous solution of the polymer (Fikentscher constant) neutralized with sodium hydroxide solution.

Copolymers of (meth)acrylic acid are also suitable, particularly suitable copolymers include, in addition to (meth)acrylic acid, ethylene, maleic acid, methyl acrylate, ethyl acrylate, butyl acrylate and/or Copolymer of ethylhexyl acrylate as comonomer. Copolymers containing at least 40% by weight, preferably at least 80% by weight, of (meth)acrylic monomers are preferred, the percentages being based on the acid form of the monomers or polymers.

[0153] For neutralizing polyacrylic acid polymers and copolymers, alkali metal and alkaline earth metal hydroxides such as potassium hydroxide, especially sodium hydroxide, are particularly suitable.

[0154] The porous membrane can be provided in various ways with one or more additives. For example, the additive can be applied to the polyolefin when the additive is complete (ie, after extraction) or added to the coating mixture used to produce the porous membrane (eg, during polymerization). According to a possible preferred embodiment, the additive or the solution of the additive can be applied to the surface of the porous membrane or to the surface of the coating. This variant is particularly suitable for, but not limited to, the use of non-thermally stable additives and additives that are soluble in the solvent used for subsequent extraction. The coating does not need to pass extraction after application. For example, after forming a PE separator through an extrusion extraction process, a coating mixture of the material and additives can be applied as a thin film on a PE film without subsequent extraction,

And if the additive coating precedes one or more conductive or anti-oxidative, stiffness enhancing coatings, the additive being a polar material can increase the adhesion between the PE substrate and the top coat.

Solvents that are particularly suitable as additives in the present invention are low molecular weight alcohols, such as methanol and ethanol, and mixtures of these alcohols with water. Application can take place on the side of the porous membrane facing the negative electrode, the side or both sides facing the positive electrode. For embodiments in which the coating is present on only one side of the porous membrane, the additive may be applied to the coating, to the uncoated side of the coating, or to both sides of the separator.

The additive may be at least 0.5 g/m², 1.0g/m², 1.5g/m², 2.0g/m², 2.5g/m², 3.0g/m², 3.5g/m², 4.0g/m², 4.5g/m², 5.0g/m², 5.5g/m², 6.0g/m², 6.5g/m², 7.0g/m², 7.5g/m², 8.0g/m², 8.5g/m², 9.0g/m², 9.5g/m²or 10.0g/m²density exists. The additive can be 0.5-10g/m², 1.0-10.0g/m², 1.5-10.0g/m², 2.0-10.0g/m², 2.5-10.0g/m², 3.0-10.0g/m², 3.5-10.0g/m², 4.0-10.0g/m², 4.5-10.0g/m², 5.0-10.0g/m², 5.5-10.0g/m², 6.0-10.0g/m², 6.5-10.0g/m², 7.0-10.0g/ 1^, 7.5-10.08 plus², 5.0-10.58 plus², 5.0-11.08 plus², 5.0-12.08 plus²or 5.0-15.08 plus²A range of densities exists on the separator.

[0157] It can also be applied by dipping the polyolefin layer into the additive or additive solution and then selectively removing the solvent (eg by drying). In this way, the application of additives can be combined with extractions such as those commonly used in the production of microporous polyolefin separator layers.

[0158] The thickness of the porous membrane is preferably greater than 0.1 mm and less than or equal to 5.0 mm. The thickness of the porous membrane may be in the range of 0.15-2.5mm, 0.25-2.25mm, 0.5-2.0mm or 0.75-1.5mm. The porous membrane may be about 0.8mm or 1.1mm thick.

In certain selected embodiments, the thickness of the back mesh of the porous membrane is not greater than 500um, 400um, 300um, 250um, 200um, 175um, 150um, 125um, 100um or less. In various embodiments, the porous membrane includes ribs. Preferred ribs may be 0.008mm to 1mm high and may be spaced 0.001mm to 10mm apart. For example, the ribs may be spaced 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2.0mm, 2.25mm, 2.5mm, 2.75mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm. In some embodiments, the ribs may be in the form of, for example, they are on one side of the separator layer or on both sides of the porous membrane, from 0 degrees to 90 degrees relative to each other. In certain selected embodiments, the ribs are at an angle of 0, 45 or 90 degrees to each other on both sides of the porous membrane. Various forms including ribs on both sides of the separator layer may include negative cross ribs on the second or back side of the separator.

[0160] According to at least another object of the present invention, a ribbed porous membrane is provided. The porous membrane may have transverse intersecting ribs on opposite sides of the porous membrane as are the longitudinal ribs. In some embodiments of the invention, the ribbed porous membrane may have a diameter of at least 0.005mm, 0.01mm, 0.025mm, 0.05mm, 0.075mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm , 0.7mm, 0.8mm, 0.9mm or 1.0mm transverse rib height. The ribbed porous membrane may have 0.005-1.0mm, 0.01-0.5mm, 0.025-0.5mm, 0.05-0.5mm, 0.075-0.5mm, 0.1-0.5mm, 0.20.4mm, 0.3-0.5mm or 0.4-0.5 Transverse rib height between mm.

In some embodiments of the invention, the ribbed porous membrane can have at least 0.005mm, 0.01mm, 0.025mm, 0.05mm, 0.075mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm , 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm or 1.5mm longitudinal rib height. The ribbed porous membrane may have 0.0051.5mm, 0.01-1.0mm, 0.025T. 0mm, 0.05-1.0mm, 0.075-1.0mm, 0.1-1.0mm, 0.2-1.0mm, 0.31.0mm, 0.4-1.0mm , transverse rib heights between 0.5-1.0mm, 0.4-0.8mm or 0.4-0.6mm.

In some embodiments of the invention, the ribbed porous membrane can have at least 0.005mm, 0.01mm, 0.025mm, 0.05mm, 0.075mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm , 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1.0mm sheet (substrate) thickness. The ribbed porous membrane may have 0.005-1.0mm, 0.01-1.0mm, 0.0251.0mm, 0.05-1.0mm, 0.075-1.0mm, 0.1-1.0mm, 0.2-1.0mm, 0.3-1.0mm, 0.4-1.0 Sheet (substrate) thickness between mm, 0.41.01^, 0.4-0.91^, 0.4-0.81^, 0.5-0.8^, or 0.6-0.81^.

In some embodiments of the invention, the ribbed porous membrane can have at least 0.05mm, 0.1mm, 0.25mm, 0.5mm, 0.75mm, 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm , 3.5mm, 4.0mm, 4.5mm, 5.0mm or 6.0mm total thickness (positive rib + back mesh + negative rib). The ribbed porous membrane may have a transverse rib height of between 0.05-5.0mm, 0.1-5.0mm, 0.2-5.0mm, 0.5-5.0mm, 1.0-5.0mm or 1.0-4.0mm.

[0164] In some cases, the ribs do not necessarily appear on one or both sides. For example, the separator, substrate or membrane may be a flat sheet or have ribs on only one side.

With regard to at least selected embodiments of the present invention, the ribbed porous membrane may have the following characteristics:

1) Transverse rib height - preferably between about 0.02 to 0.45 mm, and most preferably between about 0.075 to 0.3 mm.

2) Sheet (substrate) thickness - preferably between about 0.065 to 0.75 mm.

3) Total thickness (positive electrode rib+back mesh+negative electrode rib)-the thickness of the separator is between about 0.10 to 6.0 mm, preferably between about 0.20 to 4.0 mm.

[0169] The ribs may be serrated. The average tip length of the serrations may be 0.05 mm to 1 mm. For example, the average tip length may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0170] The average base length of the serrations may be from 0.05 mm to 1 mm. For example, the average base length may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0171] The average height of the serrations may be from 0.05mm to 1mm. For example, the average height may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm, 0.9mm mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm. For embodiments where the serration height is the same as the rib height, the serration ribs may also be referred to as protrusions.

[0172] The average center-to-center distance of the serrations may be from 0.1 mm to 50 mm. For example, the average center-to-center distance may be greater than or equal to 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.25mm or 1.5mm; and/or less than or equal to 1.5mm, 1.25mm, 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm or 0.2mm.

[0173] The serrations may have an average height to base width ratio of 0.1:1 to 500:1. For example, the ratio of the average height to the bottom width may be greater than or equal to 0.1:1, 25:1, 50:1, 100:1, 150:1, 200:1, 250:1, 300:1, 350:1 or 450:1; and/or less than or equal to 500:1, 450:1, 400:1, 350:1, 300:1, 250:1, 200:1, 150:1, 100:1, 50:1 or 25:1.

[0174] The serrations may have an average base width to top width ratio of from 1000:1 to 0.1:1. For example, the average base width to top width ratio may be greater than or equal to 0.1:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1 , 9:1, 10:1, 15:1, 20:1, 25:1, 50:1, 100:1, 150:1, 200:1, 250:1, 300:1, 350:1:450 :1, 500:1, 550:1, 600:1, 650:1, 700:1, 750:1, 800:1, 850:1, 900:1, 950:1, and/or less than or equal to 1000 :1, 950:1, 900:1, 850:1, 800:1, 750:1, 700:1, 650:1, 600:1, 550:1, 500:1, 450:1:400:1 , 350:1, 300:1, 250:1, 200:

1, 150:1, 100:1, 50:1, 25:1, 20:1, 15:1, 10:1, 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1 or 1:1.

[0175] In some embodiments, the porous membrane can be perforated. The perforations may be a row or row of holes of approximately the same size. The rows or rows may be spaced from 0.001 mm to 10 mm apart. For example, the rows can be spaced 0.05mm, 0.1mm, 0.2imn, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2.0mm, 2.25mm, 2.5mm, 2.75mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm.

[0176] The average hole length of the perforations may be from 0.05 mm to 1 mm. For example, the average tip width may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0177] The average hole width of the perforations may be from 0.01 mm to 1 mm. For example, the average hole width may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0178] The perforations may have an average center-to-center pitch of 0.1 mm to 50 mm. For example, the average center-to-center distance may be greater than or equal to 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.25mm or 1.5mm; and/or less than or equal to 1.5mm, 1.25mm, 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm or 0.2mm.

[0179] The perforations can be quadrilateral, such as squares and rectangles. The perforations may have an average pore length/pore width ratio of 0.1:1 to 1000:1. For example, the average aspect ratio may be greater than or equal to 0.1:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 1, 10:1, 15:1, 20:1, 25:1, 50:1, 100:1, 150:1, 200:1, 250:1, 300:1, 350:1, 450:1, 500:1, 550:1, 600:1, 650:1, 700:1, 750:1, 800:1, 850:1, 900:1, 950:1, and/or less than or equal to 1000:1, 950:1, 900:1, 850:1, 800:1, 750:1, 700:1, 650:1, 600:1, 550:1, 500:1, 450:1, 400:1, 350:1 1, 300:1, 250:1, 200:1, 150:1, 100:1, 50:1, 25:1, 20:1, 15:1, 10:1, 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1 or 1:1.

[0180] In some embodiments, the holes may be triangular. Typically, the triangular holes are equilateral triangles with sides ranging from 0.01 mm to 1 mm. For example, the average triangle side length may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm; and/or less than or equal to 1.0mm , 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0181] In some embodiments, the apertures may be substantially circular. The diameter of the circular hole may be from about 0.05 to 1.0 mm. For example, the average pore diameter may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm, 0.9mm mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0182] In some embodiments, the porous membrane can be dimpled. The dimples are arranged on the porous membrane in a manner similar to perforations, however, the dimples are indentations in the surface of the porous membrane rather than complete voids. The thickness of the pits may be 1-99% of the thickness of the porous membrane. For example, the average thickness of the dimples may be less than 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10% or 5%. The dimples may be arranged in rows along the porous membrane. The rows or rows may be spaced from 0.001 mm to 10 mm apart. For example, the rows may be spaced 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm , 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2.0mm, 2.25mm, 2.5mm, 2.75mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm.

[0183] The dimples may have an average dimple length of 0.05 mm to 1 mm. For example, the average pit length may be greater than

or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0184] The dimples may have an average dimple width of 0.01 mm to 1 mm. For example, the average dimple width may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm , 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0185] The dimples may have an average center-to-center distance of 0.1 mm to 50 mm. For example, the average center-to-center distance may be greater than or equal to 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.25mm or 1.5mm; and/or less than or equal to 1.5mm, 1.25mm, 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm or 0.2mm.

[0186] The shape of the pits can be quadrilateral, such as square and rectangle. The pits may have an average pit length to pit width ratio of 0.1:1 to 100:1. For example, the average length to base width ratio may be greater than or equal to 0.1:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 15:1, 20:1, 25:1, 50:1, 100:1, 150:1, 200:1, 250:1, 300:1, 350:1, 450: 1, 500:1, 550:1, 600:1, 650:1, 700:1, 750:1, 800:1, 850:1, 900:1, 950:1, and/or less than or equal to 1000: 1, 950:1, 900:1, 850:1, 800:1, 750:1, 700:1, 650:1, 600:1, 550:1, 500:1, 450:1, 400:1, 350:1, 300:1, 250:1, 200:1, 150:1, 100:1, 50:1, 25:1, 20:1, 15:1, 10:1, 9:1, 8: 1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1 or 1:1.

[0187] In some embodiments, the dimples may be substantially circular. The circular dimples may have a diameter of about 0.05 to 1.0 mm. For example, the average dimple diameter may be greater than or equal to 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm or 0.9mm; and/or less than or equal to 1.0mm , 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm or 0.1mm.

[0188] In some embodiments, the porous membrane may have a combination of serrations, pores, slits, and/or dimples. For example, the porous membrane may have a series of serrated ribs extending from top to bottom along the separator, and a second series of serrated ribs extending horizontally along the separator. In other embodiments, the porous membrane may have alternating sequences of serrated ribs, dimples, and/or perforations. Additionally, the bag, sleeve, or wrap separator may have openings or slits to allow acid movement.

[0189] According to at least one embodiment, the porous membrane is made of ultra-high molecular weight polyethylene (UHMWPE) mixed with process oil plus additives and deposited silica. According to at least one other embodiment, the porous membrane is made of ultra high molecular weight polyethylene (UHMWPE) mixed with process oil and deposited silica. Process oil can be selectively removed as described above. The additive can then be applied to the porous membrane by one or more of the techniques described above. According to at least one particular embodiment, the negative intersecting ribs are circular mini-ribs and preferably have a radius of 2 to 6 mils and a rib spacing of 10 to 50 mils.

[0190] According to at least selected embodiments, the porous membrane comprises a porous membrane having a back mesh and optionally one or more positive and/or negative ribs thereon. For example, the porous membrane may comprise a porous membrane having a back mesh and at least two positive ribs on the positive side of the back mesh, and optionally a plurality of smaller ribs on the negative side of the back mesh The negative cross rib or transverse rib. The positive rib may be straight or wavy, may have a solid portion, may have a truncated pyramid shape, may be serrated, stacked, discontinuous, continuous, nubs, protrusions or its combination. The negative electrode rib can be smaller than the positive electrode rib and can be straight or wavy, can have a solid portion, can have a truncated pyramid shape, can be serrated, stacked, discontinuous, raised, protruding, microscopic Ribs, transverse, longitudinal or combinations thereof. Also, the positive and negative side ribs may have the same dimensions (the same dimensions on both sides) and may be parallel, angled or perpendicular to each other. For example, the two sides may have small or micro-ribs, and such ribs may be parallel, angled, or perpendicular to each other. The film may be selected from polyolefin, rubber, polyvinyl chloride, phenolic, cellulose or combinations thereof, and

And the film is preferably a polyolefin (PO) material, more preferably polyethylene (PE), to form a porous or microporous film for a battery separator for a secondary battery.

In at least one embodiment, described porous membrane is made of microporous thermoplastic material, and described microporous thermoplastic material has longitudinal positive electrode rib and transverse negative electrode rib, and wherein the height of at least most longitudinal rib is greater than the height of transverse rib , and the longitudinal and transverse ribs are solid ribs integrally formed of plastic, characterized in that the transverse ribs extend across substantially the entire back width of the bulkhead. The thickness of the porous film backing web or sheet may be about 0.10 to 0.50 mm, the height of the longitudinal ribs may be 0.3 to 2.0 mm, and the height of the transverse ribs may be 0.1 to 0.7 mm, and the longitudinal stiffness with a width of 100 mm may be About 5 mJ, the lateral stiffness may be about 2.5 mJ, and the total thickness of the porous membrane may be less than 3.5 mm, preferably less than 2.5 mm.

Coating material

Exemplary coating materials described herein can impart, for example, the improved oxidation resistance, improved wettability, reduced black residue, improved surface conductivity, increased stiffness and/or improved pairing of the above-mentioned porous membranes. Resistance to metal contamination-induced oxidation. Coating materials can improve the charge acceptance and/or reduce acid stratification of batteries, especially lead-acid batteries. In some embodiments, the coating material is hydrophilic, porous, conductive, oxidation resistant or self-adhering to the porous membrane. In some selected embodiments, the coating material is hydrophilic and porous, or hydrophilic, porous and antioxidant, or hydrophilic, porous and conductive, or hydrophilic, porous , antioxidant and conductive, or any combination thereof.

[0194] Exemplary coating materials include, but are not limited to, silica, fumed silica, silica, terrestrial, alumina, metals, metal oxides, cellulose, carbon, and conductive carbon materials. In some embodiments, the coating material is a single type of material, while in other embodiments, the coating material comprises two or more of the foregoing materials, such as silica and silica, alumina and alumina, Silica and carbon, etc.

Exemplary metal oxides that may be present in the coating include aluminum oxide (Al₂O₃), boehmite y-AlO(OH), oxides of silicon oxide and transition metals, etc. or mixtures thereof.

Exemplary conductive carbons include graphite, graphene, graphene oxide, carbon nanotubes, carbon fibers, and the like.

[0197] In certain selected embodiments, the coating may contain one of the aforementioned materials in combination with a polymer, binder, or carrier material. Exemplary carrier materials include glass mats, ceramics, and polymers. Exemplary polymers include polyolefins, PVDF, PVDF:HFP, PEO, PTFE, SBR, PVA, acrylic, and/or the like. In certain embodiments, the carrier mixture is homogeneously mixed with the aforementioned materials, and in other embodiments, the materials are present in the form of particulate agglomerates.

The coating can be present on the face of the porous membrane facing the positive electrode, the face of the porous membrane facing the negative electrode or on both sides of the porous membrane. In certain embodiments, the side of the porous membrane facing the positive electrode can be coated with one material and the side of the porous membrane facing the negative electrode can be coated with a different material. In other embodiments, both sides are coated or clad with the same material.

Described one or more coatings can be present on either side of porous membrane, and thickness range is 0.1um to 250um, may preferably be 1 to 250um, 1 to 150um, 2.5 to 150um, 2.5 to 125um, 2.5 to 100um, 2.5 to 75um, 5 to 75um, 5 to 100um, 10 to 100um, 5 to 50um, 5 to 25um, 25 to 100um, 25 to 50um, 25 to 75um. In other embodiments, the coating may be applied at a very thin thickness, eg, less than 5um, 4um, 3um, 2um, 1um, 0.5um, or 0.25 rm. In other embodiments, the coating can be applied at a thicker rate, eg, greater than 5um, 10um, 15um, 20um, 25um, 30um, 35um, 40um, 50um, 75um, 100um, or 150um.

Coated Porous Membranes

[0201] The coated porous membranes described herein are preferably characterized by enhanced stiffness, oxidation resistance, wettability and/or surface conductivity, resistance to contamination-induced oxidation, reduced black residue, etc. .

Method of Coating Separator

In certain embodiments, the coating covers the entire porous membrane, and in other embodiments, the coating covers a portion of the porous membrane, such as on the ribs, on the back mesh, on the positive side, on the negative side , and/or stripes, ribbons, other forms and/or the like. The substrate or film may be a flat PE film, ribbed PE film, AGM or other substrates. When the coating is applied as ribs or stripes or other forms, the preferred substrate or film may be substantially flat. The coating layer can be applied to the porous membrane (or just the ribs) by dipping, doctor blade, curtain coating, gravure printing, solvent coating, aqueous coating, physical vapor deposition methods, atomic layer deposition methods or chemical vapor deposition methods. Physical vapor deposition (PVD) can include various vapor deposition methods and/or vacuum deposition methods for depositing thin films by condensing the desired film material in vaporized form onto various substrate surfaces. PVD is used to manufacture a variety of items, including, by way of example only, semiconductor devices, aluminized PET films for balloons and food packaging, and coated cutting tools for metalworking. Vacuum metallization is a form of physical vapor deposition, the process of bonding a metal to a non-metallic substrate by evaporation. The most commonly used metal for vacuum metallization is aluminum for various reasons, such as cost, thermodynamics and reflective properties.

[0204] In certain embodiments, a very thin coating is provided on the porous membrane. Such an embodiment may be desirable because it occupies less volume in the battery and can result in a higher volumetric and gravimetric energy density of the battery.

[0205] In forming the coatings described herein, vapor deposition techniques can be employed to deposit very thin coatings at ultra-thin thicknesses of less than um. Physical vapor deposition (PVD), chemical vapor deposition (CVD), and atomic layer deposition (ALD) are three well-known types of vapor deposition techniques. Non-limiting examples of physical vapor deposition are sputtering and evaporation. Physical vapor deposition may include evaporating metal elements, reactive metal elements, inert metal elements, or metal oxides, and forming a layer on a substrate such as a porous membrane. A vapor-deposited layer may be deposited onto the porous membrane, the vapor-deposited layer consisting of a single layer of individual atoms or molecules of a highly anti-oxidative material such as a metal and/or metal oxide. In addition, a vapor-deposited layer composed of multiple layers of highly oxidative-resistant materials such as inert metal elements, reactive metal elements, or individual atoms or molecules of metal oxide compounds can be deposited on the porous membrane. Additionally, various sequences of metals and/or metal oxides can be formed on the microporous membrane at a thickness of less than 1WD, more preferably less than about 0.5 μΐη, more preferably less than 1,0004 and most preferably less than about 5QOA Possible combination of one or more layers applied.

[0206] Atomic layer deposition (ALD), which is a thin film growth method for depositing deposits in layers, can also be used to apply coatings in a controlled manner. Typically, the vapor of the film precursor is absorbed on the substrate in a vacuum chamber. The vapor is then drawn from the chamber, leaving a thin layer of the absorbed precursor on the substrate, usually a substantially monolayer. Reactants are then introduced into the chamber under thermal conditions, which facilitate reaction with the absorbed precursor to form a layer of the desired material. The reaction product is pumped out of the chamber. Subsequent layers of material can be formed by exposing the substrate to the precursor vapor again and repeating the deposition process. ALD can produce very thin nanoscale films with extremely high density layer production and a minimal amount of defects.

[0207] Chemical vapor deposition (CVD) techniques can also be used to apply coatings in a controlled manner. Chemical vapor deposition is another widely used material processing technique for applying thin films of solids to surfaces. It is used to deposit a wide variety of materials. In its simplest embodiment, CVD involves flowing one or more precursor gases into a chamber containing one or more heated objects to which the CVD layer is to be applied. Chemical reactions occur on and near the hot surface, resulting in the deposition of thin films on the surface. The accompanying chemical by-products are exhausted out of the chamber along with unreacted precursor gases. It can be carried out in both hot and cold wall reactors, at sub-torr total pressure to above atmospheric pressure, with and without carrier gas, at temperatures typically between 200-1600°C. There are also various enhanced CVD processes that involve the use of plasma, ions, photons, lasers, hot filaments, or combustion reactions to increase deposition rates and/or decrease deposition temperatures.

Applying one or more deposition layers using PVD, CVD or ALD can provide a reliable method to control coating materials

Additional thickness of deposition. In certain selected embodiments, the thickness of one or more of the deposited layers may be ultra-thin and in the range of less than about 5 μΙη, more preferably less than about 1 μΙh, more preferably less than about ϊ,ο0OX, and most preferably the thickness less than about 5QQA. This reliable method of applying ultra-thin deposits at thicknesses less than Win may not be available using other coating methods such as dip coating, gravure printing, doctor blade, curtain coating, etc. The application of ultrathin deposition using one or more of PVD, CVD or ALD deposition methods can provide a reliable method of applying a uniform anti-oxidant layer. The level of application control achieved in PVD, CVD, or ALD deposition methods can be accurate enough to help the polymer microporous film thickness not increase significantly.

These layers or coatings can be applied as coating slurries or mixtures or layers on one or both sides of the microporous battery separator to promote, inter alia, high temperature stability in the battery, reduce acid stratification, and improve wettability , improve stiffness, reduce thermal shrinkage, control oxidation at the separator-cathode interface of batteries, and improve the safety performance of microporous battery separators, etc. Such coatings can be applied using known techniques such as, but not limited to, dip coating, doctor blade, gravure printing, curtain coating, etc., and can be applied at about 2 μm to 6 μm, 5 μm to 5 μm to one or both sides of the microporous battery separator 75μ1n or more thickness applied.

According to certain embodiments, a polymer coating containing polymer and/or ceramic particles may be applied over or together with the metal and/or metal oxide deposition layer in order to Further improve various properties of the separator, such as the thermal stability of the separator at high temperature.

[0211] According to certain embodiments, the battery separators described herein relate to polymeric microporous films onto which a deposited layer comprising a highly anti-oxidative material (eg, an inert metal element) is applied, wherein the deposited layer has a thickness of about 20 A to about 1 μm. Non-limiting examples of inert metal elements can be gold and aluminum. When the side of the microporous polymer film with the deposited layer is in contact with the cathode, depositing a chemically stable metal such as gold or cobalt onto the microporous polymer film or thin film can create an anti-oxidative layer. When the battery is a high voltage battery, oxidation can be more aggressive and a protective antioxidant layer is required to limit the oxidative degradation of the cathode by the microporous polymer membrane. Metal deposition layers according to various embodiments herein are conductive layers and can dissipate current distribution within the battery cell. In at least some embodiments, the metallic conductive deposition layers of the present invention described herein may be applied to one or more non-conductive layers of polymer layers, such as polyolefins, such as but not limited to polypropylene, polypropylene blends Polypropylene copolymers or mixtures thereof and polyethylene, polyethylene blends, polyethylene copolymers or mixtures thereof. Non-limiting examples of non-conductive layers may include single, double, triple or multilayer (coextruded or laminated) porous membranes made by dry or wet processes with added glass mats or other woven or Nonwoven layers, which are well known to those skilled in the art.

[0212] According to at least some embodiments, examples of reactive metal elements may include the conductive metal aluminum (a1). As an example of an active metal element, aluminium will form aluminium oxide (a1) when exposed to oxygen in the air₂ο₃) of the ultra-thin protective layer. A layer of A103 may be stable to further oxidation in air.

Various non-limiting examples may provide different sets of features or improvements, which may include one or any combination of the following:

1. An exemplary embodiment of enhanced conductivity can provide carbon, which can be deposited on one or both sides of the separator by various methods described herein, or by other methods known in the art superior.

2. Another exemplary embodiment may provide oxidation resistance by depositing alumina, silica, etc. on the positive side of the separator by various methods as described herein or known in the art.

3. Another exemplary embodiment may provide a reduction in black residue by using less oil on one or both sides of the baffle.

4. Yet another exemplary embodiment may be formed by depositing alumina, silica, etc. on one or both sides of the separator by various other methods described herein or known in the art. Plates provide stiffness.

5. Another exemplary embodiment can be achieved by combining on the positive side of the separator two bismuths deposited by various methods

Silica, fibers, glass fibers, cellulose fibers, etc., as well as combinations of the materials described herein, address acid stratification.

6. Another exemplary embodiment may include incorporating a cellulose coating that will provide protection against contaminants from metals such as

Resistance to oxidation caused by Cr, Mn, etc.

7. In addition, another exemplary embodiment may incorporate various geometries, such as replacing the ribs by coating alone, covering glass fibers, glass fibers, cellulose fibers, or a mixture of fibers and silica as a coating etc. [0221] 8. Further, the exemplary embodiments provided in any one of FIGS. 2-4.

9. Further, the exemplary embodiment provided in any one of FIGS. 5A and 5B.

10. Further, the exemplary embodiments provided in Figures 7 and 7A.

11. Pyrolytic silica was mixed with binder by radiation coating on the positive side and with carbon by PVD on the negative side.

12. Cellulose film with phenolic binder on the positive side and carbon on the negative side.

[0226] The range of stiffness of the separator can be measured by resistance to bending, eg, by industry standard tests or as specified in BSTE:2530. Oxidative stability can be measured by: 1) weight loss in hot sulfuric acid containing peroxodisulfate (hydrogen peroxide); or 2) Perox-80 test; or 3) by industry standard test or BSTE- 2100, 2100-3 and BSTE-2520. The range of wettability is measured in minutes (typically 3 minutes and 10 minutes) and can be measured by horizontal immersion of the separator and measuring the wettability versus time, for example by industry standard tests or as in BSTE: 2540 and 2543 stipulated. The range of surface conductivity can be measured by electrochemical impedance spectroscopy.

According to at least selected embodiment, this application or invention relates to novel or improved porous membrane or substrate, diaphragm, separator, composite material, electrochemical device, battery, manufacture this film or substrate, separator and/or Methods of batteries, and/or methods of using such films or substrates, separators, and/or batteries. In accordance with at least some embodiments, the present application relates to new or improved microporous membranes, battery separators, separators, energy storage devices including such separators, batteries, methods of making such membranes, separators and/or batteries, and /or methods of using such membranes, separators and/or batteries. According to at least some selected embodiments, the present invention relates to separators for batteries having one or more oxidative protective deposition layers. The deposited layer is preferably a thin or ultra-thin conductive or insulating deposited layer applied to the polymeric microporous membrane. Methods may use binders removed during post-processing or solvents, such as water, removed during post-processing (eg, heating/curing/annealing, etc.). In addition, the method can use a binder that will not be removed (the binder can remain or stay) and keep the fibers or particles in the wet coating. Another method includes binderless and solventless deposition methods. By using deposited layers, the energy density of the battery can be increased. Additionally, the deposition method may preferably deposit uniform layers of less than about 0.5 um. According to at least specific embodiments, the battery separators described herein relate to multilayer or composite microporous membrane battery separators that can have excellent oxidation resistance and can be stable in high voltage battery systems. According to at least its In his chosen embodiment, the present invention relates to a separator for a battery having a conductive deposition layer that is stable in the electrolyte and under the operating conditions of the battery.

[0228] The present invention may be embodied in other forms without departing from its spirit and essential characteristics, therefore, reference should be made to the appended claims rather than the foregoing to indicate the scope of the invention. In addition, the invention exemplarily disclosed herein may suitably be practiced in the absence of any element not specifically disclosed herein.

Disclosed herein are improved battery separators for various lead-acid batteries. The improved separators disclosed herein provide batteries with significantly increased battery life, improved charge acceptance, improved oxidation resistance, improved surface conductivity, improved stiffness, improved wettability, and significantly reduced Lead-acid batteries with failure rates and acid stratification.

According to at least selected embodiment, aspect or purpose, this application or invention relates to novel or improved porous membrane or substrate, barrier film, separator, composite material, electrochemical device, battery, manufacture this film or substrate, barrier Methods of plates and/or cells, and/or methods of using such films or substrates, separators and/or cells. According to at least some embodiments, the present application relates to

Novel or improved porous membranes with coatings, battery separators with coatings, separators, energy storage devices, batteries, lead-acid batteries comprising such separators, methods of making such membranes, separators and/or batteries , and/or methods of using such membranes, separators and/or batteries. The disclosed separators and batteries can have improved charge acceptance, improved surface conductivity, improved oxidation resistance, reduced acid stratification, reduced black residue, improved wettability, and/or improved stiffness.

According to at least selected embodiment, this application or invention relates to novel or improved porous membrane or substrate, diaphragm, separator, composite material, electrochemical device, battery, manufacture this film or substrate, separator and/or Methods of batteries, and/or methods of using such films or substrates, separators, and/or batteries. According to at least some embodiments, the present application relates to novel or improved porous membranes having coatings, battery separators having coatings, separators, energy storage devices having such separators, batteries, lead-acid batteries, the manufacture of such Methods of membranes, separators and/or batteries, and/or methods of using such membranes, separators and/or batteries. The disclosed separators and batteries have improved charge acceptance, improved surface conductivity, improved oxidation resistance, reduced acid stratification, improved resistance to oxidation by metal contamination, reduced black residue, improved wetting performance and/or improved stiffness.

According to at least some selected embodiments, the present invention relates to a kind of battery separator, it is the microporous polymer film of functionalization, coating, treatment etc. to combine at least one material, treatment, function or layer is added to at least one of its sides. In certain selected specific embodiments, the material, treatment, function or layer may or may not include a binder, and may include one or more materials, eg, silica, silica, ptero, alumina, metal , metal oxides, conductive carbon materials, acid stabilized cellulose, and/or the like, and/or may include one or more conductive or non-conductive or insulating layers.

According to at least some embodiments, there is provided a method of obtaining an improved separator, wherein a treatment, material or layer is applied to a polymeric microporous film, polyethylene (PE) microporous film, woven or non-woven On at least one surface or side of a woven material, nonwoven glass mat, nonwoven absorbent glass mat (AGM), nonwoven or woven PET, cellulosic nonwoven mat, and/or the like. The material, treatment or layer can be deposited by vapor deposition, chemical deposition, vacuum assisted methods, PVD, CVD, TD, DCD, PACVD, DLC, thin film coating or deposition techniques, nano thin film techniques, single atom thick coating techniques, sols - Gel, solvent coating, aqueous coating and/or similar application. In some embodiments, the material, treatment, coating, layer, or function is applied or added by a solvent-free method, a binder-free method, or a solvent-free and adhesive-free method. In other selected embodiments, the layer is applied in the presence of a binder and/or solvent, which can then be removed.

[0234] According to at least selected embodiments, a porous membrane having a porous or ionically conductive coating or layer is provided as a battery separator in a lead-acid battery, and can improve the battery's cycle life, start-up capability, and high charge acceptance.

[0235] According to at least specific embodiments, the battery separators described herein relate to multilayer or composite microporous membrane battery separators that can have excellent oxidation resistance and are stable in lead-acid battery systems. According to at least other selected embodiments, the present invention relates to a battery separator having a layer that increases oxidation resistance, improved oxidation resistance in the presence of metal ion contaminants such as magnesium ions, reduces acid stratification, improves Surface conductivity, improved charge acceptance, increased stiffness, runnability and processability, and/or increased surface wettability.

According to the embodiment selected at least, the application or the invention relate to novel, improved or optimized porous films, films or substrates, functionalized, coated or processed porous films, films or substrates, novel, improved, optimized, Functionalized or treated separators, separators, multilayer separators, lead-acid battery separators, or composites, including electrochemistry of such films, membranes, substrates, separators, separators, lead-acid battery separators, or composites Devices, batteries or battery cells, new, improved or optimized combinations or systems having such films, membranes, substrates, separators, separators, lead-acid battery separators or plates or electrodes of composite materials, making such films, membranes , substrates, separators, separators, lead-acid battery separators, composites, systems, assemblies, battery cells, devices and/or batteries, and/or methods of using such films, membranes, substrates, separators, separators, lead Methods of acid battery separators, composites, systems, assemblies, battery cells, devices and/or batteries. According to at least some embodiments, the present application relates to novel, improved or optimized, functionalized, coated

Coated or treated microporous membranes, battery separators, lead-acid battery separators, separators and/or having at least one functionalized, coated or treated surface on at least one side, ribs on at least one side thereof Lead-acid battery separators, energy storage devices, batteries, systems, combinations, and/or including such films, battery separators, lead-acid battery separators, separators and Batteries for lead-acid battery separators, methods of making such separators, battery separators, lead-acid battery separators, separators and/or lead-acid battery separators, and/or using such separators, battery separators, lead-acid battery separators Methods of acid battery separators, separators, lead acid battery separators, composites, combinations, systems, devices, battery cells and/or batteries, and the like.

[0237] The foregoing written description of structures, apparatus, and methods has been presented for purposes of illustration only. Examples are used to disclose exemplary embodiments, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. These embodiments are not intended to be exhaustive or to limit the invention to the precise steps and/or forms disclosed, and many modifications and variations are possible in light of the above teachings. Features described herein can be combined in any combination. The steps of the methods described herein can be performed in any order that is physically possible. The patentable scope of the invention is defined by the appended claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they do not have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

[0238] The compositions and methods of the appended claims are not to be limited in scope to the specific combinations and methods described herein, which are intended as illustrations of some aspects of the claims. Any combinations and methods that are functionally equivalent are intended to be within the scope of the claims. Various modifications other than the combinations and methods shown and described herein are intended to fall within the scope of the appended claims. Furthermore, although only certain representative combinations and method steps disclosed herein have been specifically described, other combinations of combinations and method steps are intended to be within the scope of the appended claims, even if not specifically recited. Thus, steps, elements, components or combinations of components may be explicitly mentioned herein, or less, however, other combinations of steps, elements, components and components are included, although not explicitly stated.

[0239] As used in and in the appended claims, the singular forms "-", "a" and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as "about" one particular value, and/or "about" another particular value. When such a range is expressed, another embodiment includes from one particular value and/or to another particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each range are significant to the other endpoint and are independent of the other endpoint.

"Optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances in which it does not.

Throughout and in the claims, the word "comprising" and variations thereof such as "comprising" and "comprising" mean "including but not limited to" and are not intended to exclude, for example, other additives, components, Integers or steps. The terms "consisting essentially of" and "consisting of" may be used in place of "including" and "comprising" to provide more specific embodiments of the invention, and are also disclosed as "exemplary" meaning Reference to "an example" is not intended to indicate a preferred or ideal embodiment "such as" is not used in a limiting sense, but is used for explanatory or exemplary purposes.

[0242] Except indicated, all numerals used in and in the claims representing geometric shapes, dimensions, etc. are to be interpreted in their simplest form and are not intended to limit the application of the doctrine of equivalents within the scope of the claims. , interpreted in terms of significant digits and ordinary rounding methods.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those disclosed in the art.

technicians usually understand the same meaning. The publications cited herein and the materials for which they are cited are specifically incorporated by reference.