Electrodes

electrode

Fig. 1 is a schematic cross-sectional view of a specific embodiment of the laser pyrolysis device taken along the middle of the laser irradiation path. The following illustration is a bottom view of an injection nozzle with one or two reactant inlets, and the top illustration is a bottom view of a collection nozzle.

Fig. 2 is a schematic diagram of a reactant conveying device used to convey a vapor reactant to the laser pyrolysis device of Fig. 1;

Figure 3 is a schematic cross-sectional view of the solid precursor transport system taken along the center of the system.

Fig. 4 is a schematic and side view of a reactant conveying device used to convey aerosol reactants to the laser pyrolysis device of Fig. 1.

Fig. 5 is a schematic and side view of an alternative embodiment of the reactant delivery device used to deliver the aerosol reactant to the laser pyrolysis device of Fig. 1.

Fig. 6 is a schematic and front view of the reaction tank of an alternative embodiment of the laser pyrolysis device, in which the material in the tank is transparent to show the inside of the device.

Fig. 7 is a front view of a specific embodiment of a laser pyrolysis device with a long reaction tank.

Fig. 8 is a cross-sectional view of the laser pyrolysis device of Fig. 7, wherein the cross-section is taken along the line 8-8 of Fig. 7.

Figure 9 is a schematic and cross-sectional view of a device for processing nanoparticle, where the cross-section is taken along the center of the device.

Fig. 10 is a schematic and front view of a specific embodiment of the battery of the present invention.

Fig. 11 is a schematic view of a specific embodiment of a cylindrical battery with improved battery characteristics, cut through a cross section.

Fig. 12 is a partial cross section of the cylindrical battery of Fig. 11 taken along the line 12-12 of Fig. 11.

Figure 13 is a schematic cross-sectional view of four thin batteries stacked in parallel.

Figure 14 is a top view of an integrated battery with integrated microelectronic components.

15 is a cross-sectional view of the integrated battery of FIG. 14 taken along the line 15-15 of FIG. 14. FIG.

Figure 16 is a top view of an alternative embodiment of the integrated battery.

Figure 17 is a plot of the degree distribution of lithium manganese oxide nanoparticle used in the example.

Figure 18 is a scanning electron micrograph showing a smooth electrode surface made when lithium manganese oxide nano particles are added to the electrode.

Figure 19 is a scanning electron photograph of the material shown in Figure 18 at a magnification of 100 times.

Fig. 20 is a scanning electron photograph of the electrode surface manufactured under the same conditions as the electrode of Fig. 18, except that commercially available lithium manganese oxide is used.

Background of the invention

The present invention relates to an improved battery electrode structure, a corresponding battery and a method for manufacturing the electrode. In particular, the improved electrode structure incorporates nanoparticles.

The miniaturization of electronic components has enabled the use of portable electronic devices, such as mobile phones, pagers, cameras, fax machines, portable stereo devices, personal secretaries, and personal computers, to grow greatly. The growth in the use of portable electronic devices has created an increasing demand for improved power supplies for these devices. Related batteries include primary batteries, that is, batteries designed for a single charge cycle, and secondary batteries, that is, batteries designed to be rechargeable. Some batteries that are essentially designed as primary batteries can be recharged to some extent.

Lithium-based batteries have become the target of many development efforts and have been sold commercially. Lithium-based batteries have achieved commercial success due to their relatively high energy density. Lithium-based batteries usually use lithium ion-containing electrolytes. The negative electrode of these batteries can include lithium metal or alloys (lithium batteries), or lithium-added compositions (lithium ion batteries). Positive electrode materials suitable for lithium-based batteries include materials that can add lithium atoms to their crystal lattice.

In order to manufacture improved batteries, various materials have been tested as active materials for the cathode (positive electrode) of lithium-based batteries. Many kinds of materials, usually chalcogenides or nitrides, can be used in lithium-based batteries. Many other electroactive materials have been found to be suitable for negative electrodes. The choice of materials for the positive and negative electrodes determines the battery voltage.

Summary of the invention

In one aspect, the present invention relates to an electrode comprising particles having an average diameter of less than about 100 nanometers, the electrode having a root mean square surface roughness of less than about 5 microns.

In another aspect, the present invention relates to an electrode comprising electroactive particles having an average diameter of less than about 100 nanometers and a binder having an average molecular weight of greater than about 1 million amu.

In yet another aspect, the present invention relates to an electrode comprising electroactive particles having an average diameter of less than about 100 nanometers and exfoliated graphite.

Furthermore, the present invention relates to an electrode having an average thickness of less than about 10 microns, the electrode comprising particles having an average diameter of less than about 100 nanometers.

Furthermore, the present invention relates to a battery comprising: a positive electrode; a negative electrode; and a separator between the positive electrode and the negative electrode, wherein at least one electrode has an average thickness of less than about 10 microns, and includes an average thickness of less than about 500 nanometers. Electroactive particles of main particle diameter. In another aspect, the present invention relates to a battery structure comprising electrodes and separators, wherein the electrodes and separators comprise polymers, which form a continuous matrix between the electrodes and the separators, and the electrodes comprise an average main Electroactive particles of particle diameter.

In a further aspect, the present invention relates to a circuit including a monolithic structure, which includes an integrated circuit and a battery, wherein the current collector of the battery is integrated with the integrated circuit, and the electrode of the battery includes an average main Electroactive particles of particle diameter.

In addition, the present invention relates to a method of manufacturing an electrode and separator structure. The method includes establishing a sharp gradient in the polymer, the polymer portion with high electroactive particle concentration forms the electrode, and the polymer substantially without electroactive particles Part contains separators.

Schematic description

Fig. 1 is a schematic cross-sectional view of a specific embodiment of the laser pyrolysis device taken along the middle of the laser irradiation path. The following illustration is a bottom view of an injection nozzle with one or two reactant inlets, and the top illustration is a bottom view of a collection nozzle.

Fig. 2 is a schematic diagram of a reactant conveying device used to convey a vapor reactant to the laser pyrolysis device of Fig. 1;

Figure 3 is a schematic cross-sectional view of the solid precursor transport system taken along the center of the system.

Fig. 4 is a schematic and side view of a reactant conveying device used to convey aerosol reactants to the laser pyrolysis device of Fig. 1.

Fig. 5 is a schematic and side view of an alternative embodiment of the reactant delivery device used to deliver the aerosol reactant to the laser pyrolysis device of Fig. 1.

Fig. 6 is a schematic and front view of the reaction tank of an alternative embodiment of the laser pyrolysis device, in which the material in the tank is transparent to show the inside of the device.

Fig. 7 is a front view of a specific embodiment of a laser pyrolysis device with a long reaction tank.

Fig. 8 is a cross-sectional view of the laser pyrolysis device of Fig. 7, wherein the cross-section is taken along the line 8-8 of Fig. 7.

Figure 9 is a schematic and cross-sectional view of a device for processing nanoparticle, where the cross-section is taken along the center of the device.

Fig. 10 is a schematic and front view of a specific embodiment of the battery of the present invention.

Fig. 11 is a schematic view of a specific embodiment of a cylindrical battery with improved battery characteristics, cut through a cross section.

Fig. 12 is a partial cross section of the cylindrical battery of Fig. 11 taken along the line 12-12 of Fig. 11.

Figure 13 is a schematic cross-sectional view of four thin batteries stacked in parallel.

Figure 14 is a top view of an integrated battery with integrated microelectronic components.

15 is a cross-sectional view of the integrated battery of FIG. 14 taken along the line 15-15 of FIG. 14. FIG.

Figure 16 is a top view of an alternative embodiment of the integrated battery.

Figure 17 is a plot of the degree distribution of lithium manganese oxide nanoparticle used in the example.

Figure 18 is a scanning electron micrograph showing a smooth electrode surface made when lithium manganese oxide nano particles are added to the electrode.

Figure 19 is a scanning electron photograph of the material shown in Figure 18 at a magnification of 100 times.

Fig. 20 is a scanning electron photograph of the electrode surface manufactured under the same conditions as the electrode of Fig. 18, except that commercially available lithium manganese oxide is used.

Detailed description of descriptive specific embodiments

The use of electroactive nano-particles in battery electrodes produces the flexibility to produce various useful structures that cannot be made with other materials. In particular, electrodes made of nano-particles can have a higher particle density. In addition, the use of nano-particles provides very smooth electrodes and the formation of very thin battery structures, which have low resistance and high current flux. It is very useful for small and/or very high power density complete batteries to form a thin structure. In addition, the use of nano particles can be used to form a battery that is part of a complete integrated circuit.

The battery includes at least one negative electrode and at least one positive electrode, and a separator between the negative electrode and the positive electrode. The separator is electrically insulated to prevent the battery from short-circuiting, but the separator conducts the ions of the electrolyte to maintain overall electrical neutrality when the current that accompanies the battery discharge or charge flows. The batteries of interest include primary batteries that cannot be recharged, and rechargeable batteries. Rechargeable secondary battery.

Suitable electroactive nano-particles can be added to the positive and/or negative electrode of the battery. The preferred electroactive nanoparticle used to form a battery pack has an average diameter of less than 100 nanometers and a very narrow distribution of main particle diameters. Preferably, both the positive electrode and the negative electrode include nano particles with different compositions, so that the overall battery structure can be combined with the improvements produced by using nano particles in each electrode. In addition, the use of nano-particles in the electrode can produce the improved battery structure described herein.

Laser pyrolysis is an excellent way to efficiently produce electroactive nanoparticle with narrow average particle diameter distribution. In particular, laser pyrolysis can be used to produce various electroactive particles, such as metal oxides and metal sulfides. The basic feature of laser pyrolysis for the successful application of the required ceramic nanoparticle manufacturing is the generation of metal-containing precursor compounds, radiation absorbers, and the reaction stream that is usually a secondary reactant. The secondary reactant can be a source of atoms required for the desired product, such as oxygen, or an oxidizing or reducing agent to drive the formation of the desired product. If the precursor is decomposed into the desired product under strong light irradiation, no secondary reactant is required. The reactant stream is pyrolyzed by an intense beam, which is usually a laser beam. As the reactant stream leaves the laser beam, the particles rapidly quench.

In order to perform laser pyrolysis, the reactants can be supplied in vapor form. Alternatively, one or more reactants may be supplied as an aerosol. The use of aerosols provides a wide range of metal precursors for laser pyrolysis purposes, not just for vapor delivery. Therefore, aerosol delivery can use less expensive precursors. Laser pyrolysis involves the reaction of the reactant stream in a reaction tank, in which any solvent present rapidly evaporates as the reactant stream enters the reaction zone. The appropriate reaction conditions of the gaseous and/or aerosol reactants are controlled to produce nanoparticle with narrow particle size distribution.

The dry powder of nano particles is produced by laser pyrolysis. Nanoparticles produced by laser pyrolysis can receive additional treatments to change the nature of the particles, such as composition and/or crystallinity. In particular, the nano particles can be heat treated in a gas atmosphere before use. Under suitable mild conditions, heat treatment can effectively modify the characteristics of the particles without destroying the original microscopic size or narrow particle size distribution. Due to the packaging of nanoscale particles, a higher density of electroactive nanoparticle can be obtained.

In order to form an electrode, nano particles are usually mixed with a binder to form an electrode. The composition of the binder can be changed to provide relatively little binder usage for a specific amount of electroactive nanoparticle. In particular, a higher molecular weight-less crystalline binder is better. Unless the electroactive particles are sufficiently conductive, additional conductive particles are included in the electrode. The conductive particles are preferably of a suitable size to take advantage of all the advantages of the nanoscale of the conductive particles. In some embodiments, the improved electrode formed of uniform nanoparticle is integrated with the ultra-thin metalized polyester as the current collector.

Very thin and/or very smooth electrodes can be formed by dispersions of nano particles in volatile solvents. The dispersion can be coated on the substrate by, for example, spin coating, spray coating, and electrophoretic coating. Additional battery components can be formed by these coating techniques or by vapor deposition. Generally, the components are coated sequentially.

By using nano particles in the electrodes, a relatively small battery structure can be formed. If properly formed, the electrode can be quite smooth. Due to the smoothness of the electrode, a relatively thin separator can be used. In order to form these small structures, if necessary, suitable small conductive particles are added to the electrode. In addition, suitable separators can be used for the formation of relatively small structures. In particular, selected embodiments of the battery structure have a total thickness of less than about 5 microns.

Due to the improved thinness of the battery structure, it can be integrated into electronic circuits. The formation of these integrated battery units is consistent with other methods of forming other integrated circuit components. In addition, by using an improved processing method, a sophisticated integrated battery structure with reduced resistance and high current flux can be formed in an integrated circuit.

A. Nanocrystalline/Nano-degree electroactive particles manufacturing

It has been found that laser pyrolysis is a valuable tool for manufacturing nanoscale electroactive and conductive particles, in particular, it includes metal particles, metal oxide particles, and metal sulfide particles. Particularly related particles are further described below. In addition, the particles produced by laser pyrolysis are materials that facilitate further heat treatment under mild conditions to expand the route of the desired metal oxide particle production. Therefore, by using laser pyrolysis alone or in combination with other methods, a wide variety of desired nanoscale particles can be produced.

The reaction conditions determine the amount of particles produced by laser pyrolysis. The reaction conditions for laser pyrolysis can be controlled quite accurately to produce particles with desired properties. Suitable reaction conditions for the production of specific types of particles usually depend on the design of the specific device. The specific conditions used to produce many kinds of different electroactive and conductive nano-particles, especially laser pyrolysis devices, are mentioned or described below. In addition, some general observations can be made about the relationship between reaction conditions and particles formed.

Increasing the laser power causes the reaction temperature in the reaction zone to increase, and at the same time a faster quenching rate. The rapid quenching rate is beneficial to the production of high-energy phases, which cannot be obtained by methods close to thermal equilibrium. Similarly, increasing the bath temperature will also facilitate the manufacture of higher energy structures. Increasing the concentration of the reactant as the oxygen source in the reactant stream also facilitates the production of particles with an increased number of oxygen atoms.

The flow rate of the reactant and the speed of the reactant gas flow are inversely proportional to the particle size, so that increasing the flow or velocity of the reactant gas results in a smaller particle size. The growth kinetics of the particles also has an important influence on the size of the resulting particles. In other words, under fairly similar conditions, different forms of product compounds have a tendency to form particles of different sizes from other phases. The light intensity/laser power also affects the particle size. Increasing the light intensity is conducive to the formation of larger particles for lower melting materials, while for higher melting materials, smaller particles are formed.

Laser pyrolysis is usually carried out with gas phase reactants. Suitable metal precursor compounds for gaseous transportation generally include metal compounds having a reasonable vapor pressure, that is, a vapor pressure sufficient to obtain the required amount of precursor vapor in the reactant stream. If necessary, the container containing the liquid or solid precursor compound can be heated to increase the vapor pressure of the metal precursor.

The carrier gas can be bubbled through the liquid precursor to facilitate the delivery of the required amount of precursor vapor. A liquid metal precursor suitable for gaseous transportation with sufficient vapor pressure can be found in the following reference materials. The solid precursor is usually heated to create sufficient vapor pressure. The carrier gas can pass through the solid precursor to facilitate the delivery of vapor pressure. A suitable container for heating and transporting the solid precursor to the laser pyrolysis device is described below. Suitable solid precursors for the manufacture of the desired nanoparticle can be found in the following references.

The use of complete gas phase reactants somewhat limits the types of precursor compounds that can be conveniently used. Therefore, technology has been developed to introduce aerosol-containing reactant precursor into a laser pyrolysis tank. The improved aerosol delivery device for the reaction system is further described in the jointly assigned and under review application on November 9, 1998, US Patent Application Serial No. 09/188,670 by Gardner et al., titled "Reactant Delivery Apparatuses", It is incorporated here as a reference.

Using an aerosol delivery device, the solid precursor compound can be delivered by dissolving the compound in a solvent. Alternatively, the powdered precursor compound can be dispersed in a liquid/solvent for aerosol delivery. Liquid precursor compounds can be delivered by pure liquids, multi-liquid dispersions, or liquid solutions such as aerosols. Aerosol reactants can be used to obtain high reactant output. The solvent/dispersant can be selected to obtain the desired properties of the resulting solution/dispersion. Suitable solvents include water, methanol, ethanol, isopropanol, other organic solvents, and mixtures thereof. The solvent should have the desired level of purity so that the resulting particles have the desired level of purity. Some solvents, such as isopropanol, are CO ₂ An important absorber of infrared light in lasers, so that if CO is used ₂ As the laser is used as the light source, no additional laser absorbing compound is needed in the reaction stream.

If the aerosol precursor is formed when the solvent is present, the solvent is preferably rapidly evaporated by the laser beam in the reaction tank, so that a gas phase reaction occurs. Therefore, the basic characteristics of the laser pyrolysis reaction do not change due to the presence of aerosols. Nevertheless, the reaction conditions are affected by the presence of aerosols. The following provides a reference for the manufacturing conditions of manganese oxide nano-particles and other nano-particles using aerosol precursors in a specific laser pyrolysis reaction tank. Therefore, the parameters of combined aerosol reactant delivery can be further explored based on the description.

Many suitable solid metal precursor compounds can be delivered from solutions, such as aerosols. The compound is preferably dissolved in the solution at a molar concentration greater than about 0.5. Generally, the greater the concentration of the precursor in the solution, the greater the output of reactants passing through the reaction tank. However, as the concentration increases, the solution becomes more viscous, causing the aerosol to have droplets of larger than required size. Therefore, the choice of solution concentration involves the balance of factors in the choice of a better solution concentration.

Preferred secondary reactants as a source of oxygen include, for example, O ₂ , CO, CO ₂ , O ₃ , And its mix. O ₂ Can be supplied as air. The secondary reactant compound should not significantly react with the metal precursor before entering the reaction zone, as this usually results in the formation of large particles.

Laser pyrolysis can be performed at various optical frequencies. The preferred light source operates in the infrared part of the electromagnetic spectrum. CO ₂ Laser is a particularly good light source. The infrared absorber contained in the reactant stream includes, for example, C ₂ H ₄ , Isopropanol, NH ₃ , SF ₆ , SiH ₄ , And O ₃ . O ₃ It can be used as an infrared absorber and as a source of oxygen. Radiation absorbers, such as infrared absorbers, absorb energy from the radiation beam and distribute the energy to drive pyrolysis of other reactants.

Preferably, the energy absorbed by the light beam increases the temperature at a rapid rate that is several times the rate of heat generated by the exothermic reaction under controlled conditions. Although this method usually involves unbalanced conditions, the temperature can be stated approximately based on the energy of the absorption zone. The laser pyrolysis method is qualitatively different from the method in the combustion reactor, where the energy source initiates the reaction, but the reaction is driven by the energy emitted by the exothermic reaction. Therefore, although the light driving method is called laser pyrolysis, even if the traditional pyrolysis is a heating method, it is not a heating method.

The inert shielding gas can be used to reduce the amount of reactant and product molecules that contact the reactant tank components. The inert gas can also be introduced into the reactant stream as a carrier gas and/or as a reaction modifier. Suitable inert shielding gases include, for example, Ar, He, and N2.

Suitable laser pyrolysis devices usually include a reaction tank isolated from the surrounding environment. Connect the reactant inlet of the reactant conveying device to produce the reactant stream passing through the reaction tank. The laser beam path intersects the reactant stream in the reaction zone. The reactant/product stream continues after the reaction zone to the outlet, where the reactant/product stream leaves the reaction tank and enters the collection device. Usually, the light source, such as a laser, is isolated outside the reaction tank, and the light beam enters the reaction tank through a suitable window.

1, a specific embodiment 100 of a laser pyrolysis system involves a reactant delivery device 102, a reaction tank 104, a shielded gas delivery device 106, a collection device 108, and a light source 110. The reactant delivery device 102 of the Figure 1 device can use alternative designs. The first reactant delivery device 102 described below may use an alternative design. The first reaction delivery device described below can be used to deliver a completely gaseous reactant. Two alternative reactant delivery devices for delivering one or more reactants such as aerosols are described.

Referring to Figure 2, the first embodiment 112 of the reactant delivery device 102 includes a source 120 of precursor compounds. For liquid or solid reactants, carrier gas from one or more carrier gas sources 122 may be introduced into the precursor source 120 to facilitate the transportation of the reactants. The precursor source 120 can be a liquid holding container, a solid precursor delivery device as described below, or other suitable containers. The carrier gas from the carrier gas source 122 is preferably an infrared absorber and/or inert gas. The carrier gas is preferably bubbled by the liquid reactant compound or delivered to the solid reactant delivery device. The amount of reactant vapor in the reaction zone is approximately proportional to the transport speed. The liquid or solid reactant can be heated to increase its vapor pressure. Similarly, part of the reactant delivery device 102 can be heated to inhibit the deposition of reactant compounds on the walls of the delivery device.

Alternatively, the carrier gas may be directly supplied by the infrared absorber source 124 and/or the inert gas source 126 as appropriate. The gas from the precursor source 120 is mixed with the gas from the infrared absorber source 124 and/or the inert gas source 126 by combining the gas in a single part in the line 128. The gases are combined at a sufficient distance from the reaction tank 104 so that the gases are completely mixed before entering the reaction tank 104. The combined gas in the pipeline 128 enters the channel 132 through the conduit 130, which is in fluid connection with the reactant inlet 134 (which may be part of the multi-inlet delivery device, as shown by the dashed line in FIG. 2).

The secondary reactant can be supplied by the secondary reactant source 138, which is a liquid reactant conveying device, a solid reactant conveying device, a gas cylinder, or other suitable containers. If the secondary reactant source 138 delivers liquid or solid reactants, the carrier gas from the carrier gas source 122 or an alternative carrier gas source can be used to facilitate the delivery of the reaction. As shown in FIG. 2, the secondary reactant source 138 transports the secondary reactant to the conduit 130 through the line 128. Alternatively, the secondary reactant source 138 may send the secondary reactant delivery line 140 to the secondary reactant inlet 144 through the conduit 142, as shown by the dashed line in FIG. 2. The inlets 134, 144 can be slightly angled to each other to facilitate gas mixing.

Using alternative transport through the reactant inlets 134 and 144, it is mainly mixed with the secondary reactant in the reaction tank after leaving the reactant inlet. It is particularly advantageous if the reactants react spontaneously. If more than two reactants are used, the additional reactants can similarly be suitably delivered via a single reactant inlet 134, via two inlets 134, 144, or via more than two reactant inlets. The mass flow controller 146 can be used to adjust the gas flow of the reactant delivery system of FIG. 2.

Referring to FIG. 3, the solid precursor conveying device 150 for vapor conveying includes a container 152 and a lid 154. The gasket 156 is located between the container 152 and the lid 154. In a preferred embodiment, the container 152 and the lid 154 are made of stainless steel, and the gasket 156 is made of copper. In this preferred embodiment, the cover 154 and the gasket 156 are fixed to the container 152. Other inert materials suitable for the temperature and pressure applied to the solid precursor system can be used, such as PyreX ^ . The container 152 is surrounded by a heater 158, which is used to fix the temperature of the solid precursor conveying device 150 at a desired value. Suitable band heaters were obtained from Omega Engineering Company of Stamford, Connecticut. The temperature of the heater can be adjusted to generate the required vapor pressure of the precursor compound. The other part of the precursor delivery system can be heated to maintain the precursor in a vapor state after the precursor leaves the container 152.

Preferably, the thermocouple 160 is inserted into the container 152 through the lid 154. Thermocouple 160 can be borrowed from Swagelok ^ Sleeve 162 or other suitable connection inserts. The line 164 provides the input flow of the carrier gas into the container 152. The line 164 preferably includes a shut-off valve 166, and can be used by Swagelok ^ The sleeve 168 or other suitable connection is inserted through the cover 154. The output pipe 170 also preferably includes a shut-off valve 172. The output tube 170 preferably enters the container 152 through the cap 154 at the sealed connection 174. The tubes 164 and 170 can be made of any suitable inert material, such as stainless steel. The solid precursor can be placed directly in the container 152, or can be placed in a smaller open container within the container 152.

As indicated above, the reactant stream may include one or more aerosols. The aerosol may be formed in the reaction tank 104 or formed outside the reaction tank 104 before being injected into the reaction tank 104. If the aerosol is produced before the injection pressure reaction tank 104, the aerosol can be introduced through a reactant inlet comparable to that used for gaseous reactants (such as the reactant inlet 134 in FIG. 2).

Referring to FIG. 4, an alternative embodiment 180 of the reactant supply system 102 is used to supply the aerosol to the channel 132. As described above, the channel 132 forms a part of the injection nozzle used to guide the reactant into the reactant tank and terminates at the port 134. The reactant supply system 180 includes an aerosol generator 182, a carrier gas/vapor supply pipe 184, and a joint 186. The channel 132, the aerosol generator 182, and the supply pipe 184 are connected in the inner volume 188. The supply tube 184 is oriented to guide the carrier gas along the channel 132. The aerosol generator 182 is installed so that the aerosol 190 is generated in the internal volume 188 of the joint 186 between the opening of the inlet channel 134 and the outlet from the supply pipe 184.

The aerosol generator 182 may operate based on various principles. For example, aerosols can be manufactured with ultrasonic nozzles, electrostatic spray systems, pressure-flow or simple atomizers, bubbling atomizers, or gas atomizers, where the liquid is forced through small holes under high pressure and is The collision gas stream is broken into particles. Suitable ultrasonic nozzles may include piezoelectric signal converters. Ultrasonic nozzles with piezoelectric signal converters and suitable broadband ultrasonic generators were obtained from Sono-Tek Company of Milton, New York, such as Model 8700-120. A suitable aerosol generator is further described in the US Patent Application Serial No. 09188,670 of Gardner et al., which is under examination and co-assigned, and the title of the invention is "REACTANTDELIVERY APPARATUSES", which is incorporated herein by reference. The additional aerosol generator can be connected to the connector 186 via the other interface 192, so that additional aerosol is generated in the inner volume 188 for delivery to the reaction tank.

The joint 186 includes an interface 192 to provide a groove from the outer joint 186 to the inner 188. In this way, the channel 132, the aerosol generator 182, and the supply pipe 184 can be installed appropriately. In a specific embodiment, the joint 186 is a cube with six cylindrical ports 192, and one port 192 extends from each side of the joint 186. The joint 186 may be made of stainless steel or other durable, non-corrosive materials. Preferably, an interface 192 seals the window 194 to provide visual observation of the interior 188. The interface 192 extending from the bottom of the joint 186 preferably includes a drain 196 so that the condensed aerosol that has not been transported by the channel 134 can be removed from the joint 186.

The carrier gas/vapor supply pipe 184 is connected to a gas source 198. The gas source 198 may include one or more gas containers connected to deliver a selected gas or gas mixture to the supply pipe 184. The carrier gas can pass through the liquid precursor conveying device or the solid precursor conveying device, so that the carrier gas includes the liquid precursor or the vapor of the solid precursor. Therefore, the carrier gas/vapor supply pipe 184 can be used to transport various required gases and/or vapors in the reactant stream (including, for example, laser absorption gas, reactant, and/or inert gas). The flow of gas from the gas source 198 to the supply pipe 184 is preferably controlled by one or more mass flow controllers 200 or the like. The liquid supply pipe 202 connects the aerosol generator 182 and the liquid supply 204. For the manufacture of ceramic particles, the liquid supply 204 can hold a liquid containing metal precursors.

In the embodiment shown in FIG. 4, the aerosol generator 182 generates an aerosol with a momentum approximately orthogonal to the flow of the carrier gas from the tube 184 to the channel 132. Therefore, the carrier gas/vapor from the supply pipe 184 guides the aerosol precursor generated by the aerosol generator 182 into the channel 132. In operation, the flow of carrier gas directs the aerosol delivered in the inner volume 188 into the channel 132. In this way, the delivery rate of the aerosol is effectively determined by the flow rate of the carrier gas.

In another preferred embodiment, the aerosol generator is arranged at an upward angle relative to the horizontal, so that the precession component of the aerosol is guided along the channel 134. In a preferred embodiment, the output guided by the aerosol generator is arranged at an angle of about 45° relative to the orthogonal direction to the opening of the channel 134 (ie, the direction from the supply tube 184 into the channel 134).

Referring to FIG. 5, another specific embodiment 210 of the reactant supply system 102 can be used to supply aerosol to the conduit 132. The reactant supply system 210 includes an outer nozzle 212 and an inner nozzle 214. The outer nozzle 212 has an upper channel 216 with an upper channel 216 leading to the rectangular outlet 218 above the outer nozzle 212, as shown in the inset of FIG. 5. The rectangular nozzle has a selected size to produce the required expanded reactant stream in the reaction tank. The outer nozzle 212 includes a drainage pipe 220 on the base plate 222. The drain pipe 220 is used to remove condensed aerosol from the outer nozzle 212. The inner nozzle 214 is fixed to the outer nozzle 212 at the hub 224.

The inner nozzle 214 may be a gas atomizer, such as a gas atomizer from Spraying Systems (Wheaton, IL), for example, model 17310-12-1x8jj. This type of gas atomizer has a diameter of about 0.5 inches and a length of 12.0 inches. Above the nozzle, a double-hole internal mixing atomizer 226 is preferred (for example, 0.055 inch gas hole and 0.005 inch liquid hole). The liquid is fed to the atomizer through the pipe 228, and the gas introduced into the reaction tank is fed to the atomizer through the pipe 230. The interaction of gas and liquid helps droplet formation.

The outer nozzle 212 and the inner nozzle 214 are concentrically combined. The outer nozzle 212 shapes the aerosol generated by the inner nozzle 214 so that it has a flat rectangular cross section. In addition, the outer nozzle 212 helps to obtain uniform aerosol velocity and uniform aerosol distribution along the cross-section. The outer nozzle 212 can be reconfigured to be used in different reaction tanks. The height of the outer nozzle 212 relative to the beam can be adjusted to produce a spray feature that generates the desired particle properties. This feature results in a 3 inch separation between the outer nozzle 212 and the beam, which is suitable for some specific embodiments.

The reaction tank 104 includes a main tank 250. The reactant supply system 102 is connected to the main tank 250 at the injection nozzle 252. The pressure in the device can heat the reaction tank 104 to a surface temperature higher than the dew point of the mixture of reactants and inert ingredients.

The end of the injection nozzle 252 has an annular opening 254 as an inert shielding gas channel, and a reactant inlet 256 (bottom left illustration), or inlets 256, 258 (bottom right illustration) as reactant channels to form a reactant stream in the reaction tank. The reactant inlets 256, 258 are preferably slits, as shown in the lower inset in FIG. 1. For example, the annular opening 254 has a diameter of about 1.5 inches and a width of about 1/8 to 1/16 inches in the radial direction. The flow of shielding gas through the opening 254 helps prevent the dispersion of reactant gas and product particles in all reactant tanks 104.

The tubular portions 260, 262 are located on either side of the injection nozzle 252. The tubular portions 260, 262 each include ZnSe windows 264, 266. The windows 264,266 are about 1 inch in diameter. The windows 264, 266 are preferably cylindrical lenses having a focusing length equal to the distance from the center of the groove to the lens surface to focus the light beam just below the center of the nozzle opening. The windows 264, 266 preferably have an anti-reflective coating. A suitable ZnSe lens was obtained from Laser PowerOptics, San Diego, California. The tubular portion 260, 262 provides displacement of the windows 264, 266 away from the main groove 250, so that the windows 264, 266 are less likely to be contaminated by reactants and/or products. For example, the windows 264, 266 are displaced from the edge of the main slot 250 by about 3 cm.

The windows 264 and 266 are sealed to the tubular parts 260 and 262 with rubber o-rings to prevent the flow of ambient air into the reaction tank 104. The tubular inlets 268,270 provide shielding gas flow into the tubular portion 260,262 to reduce the pollution of the windows 264,266. The tubular inlets 268 and 270 are connected to the shielded gas delivery device 106.

1, the shielded gas delivery device 106 includes an inert gas source 280 connected to an inert gas conduit 282. The inert gas duct 282 flows into the annular channel 284 guided into the annular opening 254. The mass flow controller 286 regulates the flow of inert gas to the inert gas duct 282. If the reactant delivery system 112 of FIG. 2 is used, the inert gas source 126 can also be used as the inert gas source for the conduit 282, if necessary. Referring to Figure 1, an inert gas source 280 or other inert gas may be used to supply inert gas to the pipes 268,270. Preferably, the mass flow controller 288 controls the flow to the tubes 268,270.

The light sources 110 are aligned to generate light beams 300 entering the window 264 and exiting the window 266. The windows 264, 266 define the light path through the main tank 250 to cross the reactant flow in the reaction zone 302. After exiting the window 266, the beam 300 hits the energy meter 304, which also acts as beam damping. A suitable energy meter was obtained from Coherent, Santa Clara, California. The light source 110 can be a laser or a strong conventional light source, such as an arc lamp. Preferably, the light source 110 is an infrared laser, especially CW CO ₂ Lasers, such as the 1800 watts maximum power output laser from PRC Corporation of Landing, New Jersey.

The reactant passing through the reactant inlet 256 of the injection nozzle 252 initiates a reactant flow. The reactant stream passes through reaction zone 302 where a reaction involving metal precursor compounds occurs. The heating of the gas in the reaction zone 302 is extremely fast, about 10 ⁵ The number of degrees C/sec depends on specific conditions. The reaction rapidly quenches as it exits the reaction zone 302, and particles 306 are formed in the reactant/product stream. The unbalanced nature of this method can produce nano-particles with high uniform size distribution and structural uniformity.

The reactant flow continues to the collector nozzle 310. In a preferred embodiment, the collection nozzle 310 is away from the injection nozzle 252 at an interval of approximately 2 cm. The small space between the injection nozzle 252 and the collection nozzle 310 helps to reduce the contamination of the reactant tank 104 with reactants and products. The collection nozzle 310 has an annular opening 312, as shown in the upper illustration of FIG. The annular opening 312 feeds into the collection system 108.

The tank pressure is monitored by a pressure gauge 320 connected to the main tank. The preferred cell pressure for the manufacture of the desired nanoparticle is generally in the range of about 80 Torr to about 650 Torr.

The reaction tank 104 has two additional tubular parts not shown. One of the additional tubular parts is recessed in the cross-sectional plane of FIG. 1, and the second additional tubular part is convex from the cross-sectional plane of FIG. 1. When viewed from above, the 4 tubular parts are approximately symmetrically distributed near the center of the groove. These additional tubular parts have windows for viewing the inside of the tank. In this device configuration, the two additional tubular parts are not directly used to facilitate particle manufacturing.

The collection system 108 preferably includes a curved channel 330 guided by the collection nozzle 310. Because of the small particle size, the product particles follow the gas flow along the curve. The collection system 108 includes a filter 332 in the gas flow to collect product particles. Due to the curved portion 330, the filter is not directly supported above the tank. Such as Teflon ^ Various materials such as polytetrafluoroethylene, glass fiber, etc. can be used in the filter, as long as the material is inert and has a fine enough mesh to capture particles. Preferred materials for the filter include, for example, fiberglass filters from ACEGlass, Inc., Vineland, New Jersey, and AFEquipment, Inc., from Sunnyvale, California.

The pump 334 is used to maintain the collection system 108 at the selected pressure. Various pumps can be used. Suitable pumps as pump 334 include, for example, the Busch B0024 pump from Busch Company of Virginia Beach, Virginia, which has a pumping power of about 25 cubic feet per minute (cfm), and The Leybold SV300 pump of Leybold Vacuum Products Company of State Export has a pumping force of about 195 cfm. It is desirable to pass the pump discharge stream through scrubbing 336 to remove any remaining reactive chemicals before being discharged to the atmosphere. For the purpose of ventilation and for safety reasons, all the devices 100 can be placed in a fume hood. Generally, the laser remains outside the fume hood due to its large size.

The pumping rate is controlled by a manual needle valve or an automatic throttle valve 338 inserted between the pump 334 and the filter 332. When the tank pressure increases due to accumulation of particles on the filter 332, the manual valve or throttle valve can be adjusted to maintain the pumping rate and the corresponding tank pressure.

This device is controlled by a computer 350. Usually, the computer controls the light source and monitors the pressure in the reaction tank. The computer can be used to control the flow of reactants and/or shield the gas.

The reaction can continue until enough particles are collected on the filter 332 so that the pump 334 cannot maintain the required pressure in the reaction chamber 104 against the resistance of the filter 332. When the pressure in the reaction tank 104 is no longer maintained at the desired value, the reaction is stopped, and the filter 332 is removed. In this embodiment, about 1-300 grams of particles can be collected at a time before the tank pressure is no longer maintained. A single time usually lasts at least about 10 hours, depending on the reactant delivery system, the type of particles manufactured, and the type of filter used.

The reaction conditions can be controlled quite accurately. In particular, the mass flow controller is quite accurate. Lasers usually have an energy stability of about 0.5%. Using manual control or throttle valve, the tank pressure can be controlled within about 1%.

The configuration of the reactant supply system 102 and the collection system 108 can be reversed. In this alternative configuration, the reactants are supplied from above the reaction tank, and product particles are collected from the bottom of the tank. In the alternative configuration, the collection system does not include a curved part, so that the collection filter is installed directly below the reaction tank.

The alternative design of the laser pyrolysis device has been described in Bi et al., US Patent No. 5,958,348, under the title of "Efficient Production of Particles by chemical Reaction", which is incorporated herein by reference. This alternative design is intended to facilitate the production of commercial particles by laser pyrolysis. Other specific embodiments and other suitable features of a commercially available laser pyrolysis device are described in the U.S. Patent Application Serial No. 09/362,631, titled "Particle Production Apparatus" of Mosso et al. Incorporated as a reference.

In a preferred embodiment of a commercially available laser pyrolysis device, the reaction tank is elongated along the beam to provide increased output of reactants and products. The original design of the device is based on the introduction of pure gaseous reactants. The above specific embodiment for aerosol reactant delivery is suitable for the design of a long reaction tank. Additional specific examples of introducing aerosols into the elongated reaction tank with one or more aerosol generators are described in the jointly assigned and under review US Patent Application No. 09188,670, titled "Reactant Delivery Apparatuses" by Gardner et al. , Which is incorporated here as a reference.

Generally, a laser pyrolysis device with a long reaction tank is designed to reduce the pollution of the tank wall, increase productivity, and efficiently use resources. In order to accomplish these goals, the elongated reaction tank provides the output of reactants and products without a corresponding increase in the volume of the ineffective tank. The volume of the ineffective tank can be contaminated by unreacted compounds and/or reaction products. In addition, the proper flow of the shielding gas limits the reactants and products to the flow through the reaction tank. The high output of the reactant effectively utilizes the laser energy.

The design of the improved reaction tank 400 is schematically shown in FIG. 6. The reactant inlet 402 is guided to the main tank 404. The reactant inlet 402 roughly conforms to the shape of the main tank 404. The main tank 404 includes an output 406 along the reactant/product stream to remove particulate products, any unreacted gases, and inert gases. The shielding gas inlet 410 is located on both sides of the reactant inlet 402. The shielded gas inlet is used to form an inert gas blanket on the side of the reaction stream to inhibit the contact between the tank wall and the reactant or product.

The tubular portions 420, 422 extend from the main groove 404. The tubular portions 420, 422 hold windows 424, 426 to define the beam path 428 through the reaction tank 400. The tubular portions 420,422 may include inert gas inlets 430,432 to introduce inert gas into the tubular portions 420,422.

The improved reaction system includes a collection device to remove nanoparticle from the reactant stream. The collection system can be designed to collect particles in a batch mode, which collects a large number of particles before stopping production. Alternatively, the collection system can be designed to be performed in a continuous manufacturing mode by switching between different particle collectors in the collection device, or by providing particle removal without exposing the collection system to the surrounding atmosphere. The preferred embodiment of the collection device for continuous manufacturing is described in the U.S. Patent Application Serial No. 09/107,729 of Gardner et al., which is under examination and co-assignment, with the title "Particle Collection Apparatus and Associated Methods", which is incorporated herein Reference. The collecting device may include a curved component in the flow path, which is similar to the curved part of the collecting device shown in FIG. 1.

Referring to FIG. 7, it shows a specific embodiment 450 of a laser pyrolysis reaction system having an elongated reaction tank. In this embodiment, a reaction tank with a reaction delivery device designed only for the delivery of gaseous reactants, or a reaction tank with a reactant delivery device that can deliver aerosol reactants and any required gas can be used. The laser pyrolysis reaction device 450 includes a reaction tank 452, a specific collection device 454, a light source 456, and a reactant delivery system connected to an inlet 464.

The reaction tank 452 includes an inlet 464 at the bottom of the reaction tank 452, and the reactant conveying device is connected to the reaction tank 452 here. The nozzle combined with the reactant conveying device can extend into the reaction tank 452 and seal the surrounding atmosphere at the inlet 464. The gaseous reactant can be conveyed by extending the nozzle substantially conforming to the elongation of the reaction tank 452. Similarly, conveying aerosols can be used for the elongated shape of the reaction tank.

In this specific embodiment, the reactants are transported from the bottom of the reaction tank 452, while the products are collected from the top of the reaction tank 452. The configuration can be reversed to supply reactants from the top and collect products from the bottom, as shown in Figure 6. The shielding gas conduit can be placed at a suitable position near the reactant delivery nozzle extending into the reactant inlet 464. The shielding gas conduit guides the shielding gas along the wall of the reaction tank 452 to prevent the reactant gas or product from combining with the wall.

The reaction tank 452 is elongated along the dimension indicated by "w" in FIG. 7. The laser beam path 466 enters the reaction tank 452 through the window 468 arranged along the tube 470 through the main tank 472, and passes through the elongation direction of the reaction tank 452. The laser beam passes through the tube 474 and exits the window 476. In a preferred embodiment, the displacement windows 468 and 476 of the tubes 470 and 474 are about 11 inches from the main groove 472. The laser beam terminates at beam damping 478. In operation, the laser beam crosses the reactant stream generated by the nozzle inserted into the reactant inlet 464.

The top of the main tank 472 opens into the particle collection system 454. The particle collection system 454 includes an outlet duct 480 connected to the top of the main tank 472 to receive the flow from the main tank 472. The outlet conduit 480 carries the particles above the plane of the reactant flow to the round particle filter 482, as shown in FIG. 8. The filter 482 has a cover 484 at one end to prevent the guide flow from entering the center of the filter 482. The other end of the filter 482 is fastened to the dish 486. The vent 488 is fixed at the center of the dish 486 to provide access to the center of the filter 482. The vent 488 is connected to the pump by a pipe.

In this way, the product particles are captured in the filter 482 by the flow from the reaction tank 452 to the pump. Suitable pumps are as described above with respect to the first layer pyrolysis device of Figure 1. Suitable filters for the filter 482 include, for example, air filters for Saab9000 cars (Purilator part number A44-67), which have Plasticol ^TM Or wax paper for polyurethane end cap 484.

The collection device shown in FIGS. 7 and 8 is suitable for the operation of the reaction tank 452 in a batch mode, where the operation is stopped when the filter 482 no longer collects additional particles. As described above, the alternative collection device is suitable for operating the reaction tank 452 in continuous operation. The dimensions of the elongated reaction tank 452 and the reactant inlet 464 are preferably designed for high-efficiency operation and manufacturing. 1800 watt CO in use ₂ When lasering, the reasonable size of the reactant inlet 464 used for the manufacture of ceramic nanoparticle is about 5 mm to about 1 meter.

B. Heat treatment of nano particles

As shown above, the properties of the nanoparticle can be modified by heat treatment. Suitable starting materials for heat treatment include nano particles produced by laser pyrolysis. In addition, the nanoparticle as a starting material may have undergone one or more previous heating steps under different heating conditions. For the heat treatment of nanoparticle formed by laser pyrolysis, additional heat treatment can improve the crystallinity, remove pollution, such as elemental carbon, and can change the stoichiometry, for example, by additional oxygen or derived from other gaseous or non-gaseous compounds Atomic bonus.

The nano particles are preferably heated in an oven or the like to provide substantially uniform heating. The processing conditions are generally mild, so that a large amount of particle sintering does not occur. Therefore, the heating temperature is preferably lower than the melting point of the starting material and the product material.

The atmosphere on the particles can be static, or the gas can flow through the system. The atmosphere used in the heating process can be an oxidizing atmosphere or an inert atmosphere. In particular, in order to transform amorphous particles into crystalline particles, or from a crystalline structure to a different crystalline structure with essentially the same stoichiometry, the atmosphere is usually inert.

Suitable oxidizing gases include, for example, O ₂ , O ₃ , CO, CO ₂ , And combinations thereof. O ₂ Can be supplied as air. Oxidizing gas can be mixed according to the situation, such as Ar, He, and N ₂ The sentiment. When the inert gas is mixed with the oxidizing gas, the gas mixture may include about 1% of the oxidizing gas to about 99% of the oxidizing gas, and more preferably about 5% of the oxidizing gas to about 99% of the oxidizing gas. Alternatively, an essentially pure oxidizing gas or pure inert gas can be used as required. In other alternative embodiments, reducing gas is used. Suitable reducing gas includes H ₂ 。

The precise conditions can be changed to change the type of nanoparticle manufactured. For example, temperature, heating time, heating and cooling rate, gas and gas exposure conditions can all be selected to produce the desired product particles. Generally, when heating in an oxidizing atmosphere, the longer the heating period, the more oxygen is added to the material before reaching equilibrium. Once the equilibrium conditions are reached, all conditions determine the crystalline phase of the powder.

The oven can be used for heating. An example of a device 500 for performing this processing is shown in FIG. 9. The device 500 includes a bottle 502, which can be made of glass or other inert material, and contains particles. A suitable glass reactor bottle was obtained from Ace Glass Company (Vineland, New Jersey). The top of the glass bottle 502 is sealed with a glass cover 504, and a Teflon® gasket 506 is arranged between the bottle 502 and the cover 504. The cover 504 may be held in place by one or more clips. The cover 504 includes a plurality of holes 508' each with a Teflon® bushing. The multi-blade stainless steel stirrer 510 is preferably inserted into the cover 504 through the central hole 508. The stirrer 510 is connected to a suitable motor.

One or more tubes 512 are inserted into the holes 508 to deliver gas into the bottle 502. The tube 512 can be made of stainless steel or other inert materials. The diffuser 514 may be included at the top of the tube 512 to suck out the gas in the bottle 502. The heater/furnace 516 is usually placed near the bottle 502. A suitable stay heater was obtained from Glas-col Corporation (Terre Haute, Indiana). Preferably, a T-connector 518 is included. The temperature in the bottle 502 can be measured by inserting the thermocouple 518 in the T-connector 518. The T-connection 518 can also be connected to the vent 520. The vent 520 provides ventilation of the gas circulating through the bottle 502. Preferably, the vent 520 ventilates to a fume hood or alternative ventilation device.

Preferably, the required gas flows through the bottle 502. The tube 512 is usually connected to an oxidizing gas source and/or an inert gas source. Oxidizing gas, inert gas or a combination of the required atmosphere is placed in the bottle 502 from a suitable gas source. Various flow rates can be used. The flow rate is preferably 1 standard cubic centimeter (sccm) per minute to about 5000 sccm, and more preferably about 100 sccm to about 2000 sccm. The flow rate is usually fixed during the treatment step, although the gas flow rate and composition can be systematically changed over time during the treatment if necessary. Alternatively, a static gas atmosphere can be used.

For many kinds of processing of microparticles in the material, the suitable temperature usually depends on the processing material. For most materials, the suitable temperature range is about 50°C to about 700°C, and in most cases, about 60°C to about 600°C. The heating usually lasts more than about 5 minutes, and generally lasts about 1 hour to about 120 hours, and in most cases, about 1 hour to about 25 hours. The preferred heating time and temperature depend on the specific starting material and target product. Some experimental adjustments may be required to create conditions suitable for producing the required materials. Use mild conditions to avoid sintering between particles generated by larger particle sizes. Controlled sintering of some particles can be performed at a slightly higher temperature to produce a slightly larger average particle diameter.

Will crystallize VO ₂ Transformed into orthorhombic system V ₂ O ₅ Crystal V with 2-D ₂ O ₅ , And the amorphous V ₂ O ₅ Transformed into orthorhombic system V ₂ O ₅ Crystal V with 2-D ₂ O ₅ , Described in the U.S. Patent Application Serial No. 08/897,903 of Bi et al. under examination and co-assignment, and the title of the invention "Processing of Vanadium OxideParticles With Heat", which is incorporated herein by reference. The conditions for removing the carbon coating from the metallic nanoparticle are described in Reactant US Patent Application Serial No. 09/123,255, and the title of the invention is "Metal (Silicon) Oxide/Carbon Composite Particles", which is incorporated herein by reference. Lithium is added to metal oxide nanoparticle by lithium salt during the heat treatment process. It is described in the U.S. Patent Application No. 09/311,506 of Reitz et al., which is under examination and co-assignment, and the title of the invention is "Metal Vanadium Oxide Particles". The U.S. Patent Application Serial No. 09/334,203 of Kumar et al., jointly assigned, and the title of the invention "Reaction Method For Producing TernaryParticles", are incorporated herein by reference.

C. The nature of the particles

The particles of interest usually have a major particle size of less than about 500 nanometers, preferably about 5 nanometers to about 100 nanometers, more preferably about 5 nanometers to about 75 nanometers, and even more preferably about 5 nanometers to about The average diameter is about 50 nanometers. The particle diameter can be estimated by a penetrating electron microscope. Preferably the particles comprise metal oxides or metal sulfides.

The main particles usually have an approximately spherical glossy appearance. In closer inspection, the crystal grains usually have facets corresponding to the underlying crystal lattice. Nevertheless, the main crystalline particles tend to exhibit approximately equal growth in three physical dimensions, resulting in a glossy spherical appearance. Amorphous particles usually have an even more spherical state. In a preferred embodiment, 95% of the main particles, and preferably 99%, have a ratio of the length along the major axis to the minor axis of less than about 2. The diameter measurement of asymmetric particles is based on the average of the length measurement along the major axis of the particle.

Because of its small size, the main particles tend to form loose viscosities due to their proximity to van der Waals forces and other magnetic forces between the particles. These viscous polymers can be dispersed to a high degree. The size of the secondary or cohesive particles depends on the method used to disperse the particles after they are initially formed. The degree of dispersion usually depends on the fluid/liquid used to disperse the particles, pH, ionic strength, and the presence of dispersing agents (such as surfactants). Nanoparticles produced by laser pyrolysis are usually well dispersed, as described in the US patent application filed by Reitz et al., which is under review and co-assignment, on November 4, 1999, the name of the invention is "Particle Dispersions", which is here Incorporated as a reference.

Even if the particles form a loose viscous polymer, the nanometer level of the main particles can be observed under a penetrating electron microscope. The particles usually have a surface area corresponding to the nanometer range particles, as observed in the photomicrographs. In addition, the particles can exhibit unique properties due to their small size and large surface area per material weight. For example, vanadium oxide nano-particles can exhibit surprisingly high mass density in lithium batteries, as described in Bi et al., US Patent No. 5,952,125, titled "Batteries With Electroactive Nanoparticles", which is incorporated herein by reference.

The main particles preferably have high uniformity in size. As mentioned above, laser pyrolysis usually produces particles with a very narrow range of particle diameters. In addition, heat treatment under appropriate mild conditions does not change the very narrow range of particle diameters. When using aerosol delivery for laser pyrolysis, the particle diameter distribution is particularly sensitive to reaction conditions. Nevertheless, if the reaction conditions are properly controlled, a very narrow particle diameter distribution can be obtained with an aerosol delivery system. As determined by penetrating electron microscope inspection, the main particles usually have a diameter such that at least about 95%, and preferably 99%, of the main particles have a diameter greater than about 40% of the average diameter and less than about 160% of the average diameter. Size distribution. Preferably, the main particles have a diameter distribution such that at least about 95%, and preferably 99%, of the main particles have a diameter greater than about 60% of the average diameter and less than about 140% of the average diameter.

In addition, in a preferred embodiment, the non-primary particles have an average diameter greater than about 4 times the average diameter, and preferably 3 times the average diameter, and more preferably 2 times the average diameter. In other words, the particle size distribution effectively does not show tails with a small number of very large-sized particles. It is the result of the small reaction area and the corresponding rapid quenching of the particles. The effective occlusion of the tail of the size distribution means that there are less than about 1 particle in 106 having a diameter greater than the specific occlusion value above the average diameter. The narrow size distribution, lack of distribution tails, and approximately spherical morphology can be utilized in many applications.

In addition, nanoparticle usually has a very high degree of purity. The nanoparticle produced by the above method is expected to have a purity greater than that of the reactant, because the laser pyrolysis reaction and crystal formation method (when applicable) tend to exclude contaminants from the particle. In addition, the crystalline nano-particles produced by laser pyrolysis have high crystallinity. Similarly, the crystalline nano-particles produced by the heat treatment method have high crystallinity. Impurities on the surface of the particles can be removed by heating the particles to obtain not only high crystal purity, but also high total purity.

Many different types of nanoscale electroactive particles have been produced by laser pyrolysis with or without additional treatment. The manufacture of vanadium oxide nanoparticles and the manufacture of batteries based on these particles are described in Bi et al.'s U.S. Patent Application Serial No. 08/897,778, the name of the invention "VanadiumOXide Nanoparticles", and Bi et al. US Patent No. 5,952,125, titled "Batteries with Electroactive Nanoparticles", all of which are incorporated herein by reference. Surprisingly high energy density is obtained with these vanadium oxide nano particles.

Similarly, silver vanadium oxide nano-particles have been manufactured, as described in the U.S. Patent Application Serial Nos. 09/246,076 and 09/311,506 that are under examination and co-assignment. The invention names are "Metal Vanadium Oxide Particles". This is incorporated as a reference. Surprisingly high capacitance ratios have been observed for these materials.

Laser pyrolysis has been used to form nanoscale manganese oxide particles. The manufacture of these particles is described in the U.S. Patent Application Serial No. 09/188,770 of Kumar et al., which is under examination and co-assigned, and the title of the invention is "Metal Oxide Particles", which is incorporated herein by reference.

In addition, laser pyrolysis followed by heat treatment has been used to produce lithium manganese oxide nano-particles, such as Kumar et al.'s U.S. Patent Application Serial No. 09/188,768, titled "Composite Metal OxideParticles", Horne. The serial number 09/203,414 of Kumar et al., title of invention "Lithium Manganese Oxides and Batteries", and 09/334,203 of Kumar et al., title of invention "Reaction Methods for Producing Ternary Particles", all of which are incorporated herein by reference. It has been observed that the nanoscale lithium manganese oxide particles placed in the cathode of a lithium-based battery can reversibly cycle in a higher voltage range than the bulk material. The use of nanoscale lithium manganese oxide particles in lithium-based batteries is also described in Iwata et al.'s US Patent No. 5,807,646, and the title of the invention is "Spinel Type Lithium-Manganese Oxide Material, Process for Preparing the Same and USe Thereof". Enter as a reference.

In addition, laser pyrolysis has been used to produce tin oxide nano-particles, as described in the U.S. Patent Application Serial No. 09/042,227 of Kumar et al., which is under examination and co-assignment, and the title of the invention is "Tin Oxide Particles", which is here Incorporated as a reference. Tin oxide particles are suitable for the negative electrode of lithium-based batteries as electroactive materials.

It has also used laser pyrolysis to produce molybdenum disulfide (MoS ₂ ) Nanoparticles, such as Brandow et al. "Electronic and vibrational properties of Rb-intercalated MoS ₂ nanoparticles", Material Science and Engineering, Volume A204, 222-226 (1995), which is incorporated herein as a reference. Carbonyl molybdenum (Mo(CO) ₆ ) And H ₂ S is the precursor, and C is used ₂ H ₂ The laser absorbs gas.

D. Battery structure and composition

10, the battery 600 generally includes a negative electrode 602, a positive electrode 604, and a separator 606 between the negative electrode 602 and the positive electrode 604. A single battery may include multiple positive electrodes and/or negative electrodes. The electrolyte can be supplied in many ways as described below. The battery 600 preferably includes current collectors 608 and 610 each combined with a negative electrode 602 and a positive electrode 604. If necessary, each electrode can be combined with multiple current collectors.

The reduction/oxidation reaction of lithium used batteries because it is the lightest metal and because it is the most positively charged metal. The electrolyte includes lithium ions. Therefore, lithium metal or lithium metal alloy can be used as the negative electrode of the battery. This type of battery is usually called a lithium battery. Alternatively, the negative electrode may include an electroactive composition added with lithium ions, which produces a net reduction of the electrode including added ions. A battery with a positive electrode and a negative electrode containing lithium-containing additive compounds and a liquid lithium-containing electrolyte is generally called a lithium-ion battery. Similarly, a battery with a positive electrode, a negative electrode containing a lithium-containing additive compound, and a solid polymer electrolyte is generally called a lithium polymer battery. Nanoparticles can be used to form thin non-lithium-based batteries that also have the improved characteristics described herein.

Some electroactive materials undergo reversible or partially reversible changes during discharge and can be recharged. Such recyclable materials can be used to form secondary, ie, rechargeable batteries. Other materials undergo irreversible or nearly irreversible changes during discharge. These irreversible materials are suitable for forming primary batteries. If necessary, recyclable electroactive materials can be used in the formation of primary batteries.

Lithium is added to the crystal lattice of the positive electrode electroactive material during battery discharge. Similarly, lithium ions leave the crystal lattice of the negative electrode during discharge. During discharge, the positive electrode serves as the cathode and the negative electrode serves as the anode. For secondary batteries, lithium leaves the crystal lattice of the positive electroactive material when recharging, that is, when voltage is applied to the battery, current flows into the positive electrode due to the application of external EMF to the battery. Similarly, lithium is added to the crystal lattice of the negative electrode when it is recharged.

The negative electrode 602 can be composed of various materials suitable for lithium ion electrolytes. For example, the negative electrode 602 may include electroactive nano-particles held by a binder. In the case of lithium batteries, the negative electrode may include lithium metal or lithium alloy formed by foil, grid or metal particles, and possibly a binder.

Lithium-ion batteries use particles of a composition that can add lithium to the negative electrode. The particles can be retained on the negative electrode with a binder. Suitable additive compounds include, for example, graphite, synthetic graphite, coking coal, neutral carbon, doped carbon, fullerenes, five alumina, tin alloy, SnO ₂ , Lithium titanium oxide, and mixtures, complexes and derivatives thereof. The manufacture of tin oxide nanoparticle is described in the U.S. Patent Application Serial No. 09/042,227 of Kumar et al., which is under examination and co-assignment, with the title of "Tin Oxide Particles", which is incorporated herein by reference.

10, the positive electrode 604 includes lithium-added electroactive nanoparticle such as lithium manganese oxide nanoparticle, which is held together using a binder such as a polymer binder. For the manufacture of lithium-based batteries, suitable electroactive compounds for positive electrodes include, for example, vanadium oxide, tin oxide, titanium oxide, silver vanadium oxide, manganese oxide, lithium manganese oxide, lithium cobalt oxide Compounds, lithium nickel oxide, lithium titanium oxide, iron sulfide, molybdenum sulfide, and mixtures, composites and derivatives thereof.

The nanoparticle used for the negative electrode 602 or the positive electrode 604 can generally have any shape, for example, approximately spherical nanoparticle or long nanoparticle. The negative electrode 602 or the positive electrode 604 may include a plurality of nano particles each having a different composition, for example, a positive electrode having a combination of lithium manganese oxide particles and vanadium oxide particles.

Although some electroactive materials are reasonable electrical conductors, in addition to electroactive nanoparticle, the positive electrode and the particle-based negative electrode usually include conductive particles. These supplementary conductive particles are usually also retained by adhesives. The conductive particles preferably have an average diameter of less than about 500 nanometers, more preferably less than 100 nanometers, and more preferably about 5 nanometers to about 50 nanometers. The presence of nano-sized conductive particles in the electrode provides a high filling density of all particles, and a smooth and thin electrode. Generally speaking, conductive particles with an average diameter smaller than the average diameter of the electroactive particles are used, and a low weight percentage of the conductive particles is used to obtain a good dispersion of the electroactive particles in the electrode. Suitable conductive particles include conductive carbon particles, such as carbon black, graphite, amorphous carbon, carbon fiber, exfoliated graphite, and metal particles, such as silver particles, stainless steel fibers, and the like. Nano-scale conductive carbon black is commercially available. In particular, acetylene black having an average diameter of about 30 to about 45 nanometers is commercially available.

In addition, nano particles of precious metals (including silver) have been produced by laser pyrolysis. The manufacture of silver particles with an average diameter of less than about 100 nanometers is described in the U.S. Patent Application Serial No. 09/311,506 of Kumar et al., which is under examination and co-assignment, with the title "Metal Vanadium Oxide Particles", which is incorporated herein as refer to.

Expanded graphite can get particularly good conductivity at low carbon concentration. Expanded graphite has randomly oriented separated graphite layers. Electroactive particles can be filled near the expanded graphite plane. Expanded graphite was obtained from Superior Graphite Company of Chicago, Illinois.

High particle load can be obtained with binder. The particles preferably have a composition greater than about 80% by weight of the positive electrode, and more preferably greater than about 90% by weight. Due to the small size of the nanoparticle, the electroactive particles can be very tightly packed in the electrode. Therefore, a very high adhesion density, that is, the density of electroactive particles, can be obtained. The use of preferably highly uniform electroactive particles and binders helps to obtain even higher electroactive particle density values. The density of the electroactive particles depends on the material involved, because different materials have different inherent densities. Generally, for electroactive nano particles, the density in the electrode ranges from about 1.4 g/cm ^3 to about 7.1 g/cm ^3. Nevertheless, the density of the electroactive lithium manganese oxide particles in the electrode can be greater than about 2.0 g/cm³, preferably from about 2.05 to about 2.7 g/cm, and more preferably from about 2.10 to about 2.7 g/cm³.

The binder can be any suitable polymer, such as polyvinylidene fluoride, polyethylene oxide, polyethylene, polypropylene, polytetrafluoroethylene, polyacrylate, ethylene-(propylene-diene monomer) copolymer (EPDM) ), and its mixtures and copolymers. For bonding nano-particles, polymer binders with high molecular weight and corresponding low crystallinity and high flexibility are preferred.

The current collectors 608, 610 facilitate the flow of current from the battery 600. The current collectors 608, 610 are conductive and are usually made of metal, such as nickel, iron, stainless steel, aluminum, and copper, and may be metal foil or preferably a metal grid. The current collector can be formed as a thin layer of conductive nanoparticle, and possibly bonded with the same adhesive as the electroactive particles. The current collectors 608, 610 can be on the surface of the bonding electrode, or embedded in the bonding electrode. The required properties of the current collector depend on the structure and use of the battery. For the integrated battery components described below, the current collector can be thinner because the current does not need to travel a long distance, and the current value is usually small.

The separator element 606 is electrically insulated and provides at least some types of ion channels. Ion penetration through the separator provides electrical neutrality in different parts of the battery to compensate for the current flow. The separator generally prevents the electroactive compound in the positive electrode from contacting the electroactive compound in the negative electrode. The separator can be used with liquid electrolyte so that the separator only acts as a physical barrier. Alternatively, the separator may include an electrolyte within the separator structure, so that no liquid electrolyte is required. In these cases, the combined separator and electrolyte are called solid electrolytes. Generally, the solid electrolyte is formed with a polymer matrix, and the resulting structure is a solid polymer electrolyte. In addition, solid state separators can be based on inorganic materials. For example, suitable solid electrolytes include lithium phosphorus oxynitride (LIPON), Li _0‧33 La _0‧56 TiO ₃ (See Brouse et al. J. Power Sources 68: 412 (1997)), and Li _2x Sr _1-2x M _0.5-x Ti _0.5+x O ₃ , Where M is a metal, such as Cr, Fe, Co, Al, In, or Y, preferably Li _0.5 Sr _0.5 (Fe or Cr) _0.25 Ti _0.75 O ₃ (See Watanade J. Power Sources 68:421 (1997)).

Various materials can be used for the divider. For example, the separator may be formed of glass fibers, which form a porous matrix. Preferably the separator is formed of a polymer, such as one suitable for use as an adhesive. The polymer separator can be porous to provide ion conduction. If the polymer in the separator is the same as the polymer binder in the electrode, an electrode separator structure can be formed in which electroactive particles generate a concentration gradient in the continuous polymer phase.

The solid electrolyte includes lithium ions in a solid matrix. Solid electrolytes based on polymers (such as polyethylene oxide) add electrolytes to the polymer matrix to provide ion conduction without the need for liquid solvents.

Lee et al. US Patent 4,830,939, titled "RadiationCured Solid Electrolyte and Electrochemical Devices Employing Same", which is incorporated herein by reference, describes the use of polyethylene unsaturated compounds in the formation of solid electrolytes. The compound preferably includes multiple heteroatoms, such as oxygen and nitrogen, and a radiation polymerizable capping group. The radiation hardenable electrolyte mixture includes a polymerizable polymer, an inert liquid, and a lithium salt.

Shackle et al. US Patent No. 5,037,712, titled "Preparation of Radiation Cured Solid Electrolytes and Electrochemical Devices Employing the Same", which is incorporated herein by reference, and describes the use of cross-linkable polysiloxanes or polyethylene oxides. Before the crosslinkable polymer is exposed to light-like radiation to crosslink the material, an ion conductive liquid and a suitable salt are mixed.

The electrolyte used in lithium batteries or lithium ion batteries may include any lithium salt. The preferred lithium salt has an inert anion and is non-toxic. Suitable lithium salts include, for example, lithium hexafluorophosphate, lithium hexafluoroarsenate, two (trifluoromethanesulfonamide) lithium, trifluoromethanesulfonate, ginseng (trifluoromethanesulfonyl) lithium methoxide, four Lithium fluoroborate, lithium perchlorate, lithium tetrachloroaluminate, lithium chloride, and lithium pentafluorobutane.

If a liquid solvent is used to dissolve the electrolyte, the solvent is preferably inert and does not dissolve the electroactive material. Generally suitable solvents include, for example, propylene carbonate, dimethyl carbonate, diethyl carbonate, 2-methyltetrahydrofuran, dioxane, tetrahydrofuran, 1,2-dimethoxyethane, ethylene carbonate, γ -Butyrolactone, dimethyl sulfenite, acetonitrile, formamide, dimethyl formamide, and nitromethane.

The shape of the battery pack can be adjusted to suit the required final product ^， For example, coin batteries, rectangular construction, or pellet-shaped batteries. Batteries usually include a casing with a portion of the current collector and/or electrodes that properly electrically contact the battery. If liquid electrolyte is used, the housing should prevent electrolyte leakage. The casing can help maintain battery components close to each other to reduce electrical resistance and diffusion resistance in the battery. Multiple batteries can be placed in a single housing, and the batteries are connected in series or in parallel.

E. Thin electrodes and batteries based on nano-particles

The electroactive nanoparticle provides a very high current density, and therefore, the high energy density due to the high surface area of the nanoparticle. In addition, if the additional components of the electrode are appropriately selected, the electrode can be made very smooth. The use of nanoparticle components with a narrow particle size distribution is particularly advantageous for the formation of a very smooth electrode surface. The lack of larger particles due to the tail of the particle size distribution reduces the possibility of having coarse locations on the electrode surface (due to unusually large particles at this location). In particular, the electrode used for the formation of the thin structure of interest has a thickness of less than about 5 microns, preferably less than about 2.5 microns, more preferably less than 1 micron, even more preferably less than about 500 nanometers, and even more preferably It is about 100 nanometers to about 250 nanometers of root mean square surface roughness. The surface roughness measurement described here is obtained with an atomic force microscope. Comparable results can be obtained using measurements based on fine probes, as used in the semiconductor industry. Having very smooth electrodes helps the manufacture of very thin electrodes and batteries.

The improved battery structure described here includes at least one very thin electrode. These thin electrodes preferably have an average thickness of less than about 10 microns. In some embodiments, the electrode has a thickness of about 100 nanometers to about 5 nanometers, more preferably about 250 nanometers to about 2.5 micrometers, and even more preferably about 300 nanometers to about 1 micrometer.

In some desirable embodiments, the improved battery structure has two thin electrodes, each of which is less than 10 microns thick. In addition, the divider is also thin. Preferably the separator is less than about 10 microns, preferably about 100 nanometers to about 5 microns, more preferably about 250 nanometers to about 2.5 microns, and even more preferably about 300 nanometers to about 1 micron. The separator must provide an electrical insulation layer between the positive electrode and the negative electrode. If the electrodes are smooth, thinner separators can be used without undesirably increasing the risk of separator breakage. Since the pre-formed separator is not helpful to the battery load, it has no harmful effect on reducing the thickness of the separator, as long as the separator provides electrical insulation between the positive electrode and the negative electrode.

Similarly, for the manufacture of very thin battery structures, any current collector should be very thin. The suitable thickness of the current collector depends on the battery structure. For the integrated battery structure described below, the current collector is preferably less than about 0.5 microns thick, and more preferably 0.05 microns to about 0.25 microns. The thin metal layer used as the current collector can be deposited by vapor deposition, such as vapor deposition, sputtering, etc.

For a standard battery structure using a thin battery structure, the current must flow through a larger distance in the battery, which requires a thicker current collector to reduce resistance. For these applications, the current collector is generally less than about 10 microns thick, preferably less than about 5 microns thick, more preferably less than about 2.5 microns thick, and even more preferably about 0.25 microns to about 1 microns thick. The current collector can be vapor deposited, or the current collector can be formed of a thin metal foil such as a sheet or a grid. Similarly, thin metalized polyester can be used as a current collector. Thin metalized polyester is used in the manufacture of capacitors by Carli Electronics Co., Ltd. in Taiwan.

Therefore, the improved battery structure has a positive electrode, a negative electrode, a separator, and a current collector, which have a combined thickness of less than about 50 microns, preferably less than about 20 microns, and more preferably about 1 to about 10 microns. For integrated batteries, the battery structure has a thickness of about 500 nanometers to about 15 micrometers, more preferably about 1 micrometer to about 7.5 micrometers, and even more preferably about 1 micrometer to about 5 micrometers. These thin battery structures can have very high energy densities.

For example, as described below, thin battery structures are particularly useful in the manufacture of integrated battery modules. In addition, various other improved battery structures can be formed from thin battery components. For example, a very large sheet can be formed from the above-mentioned extraordinary battery structure. These sheets can be rolled to make cylindrical batteries, as shown in Figures 11 and 12. The battery 630 is electrically connected to the positive contact 632 of the current collector 634 combined with the positive electrode 636, and is electrically connected to the negative contact 638 of the current collector 640 combined with the negative electrode 642. The separator 644 is located between the positive electrode 636 and the negative electrode 642. The separator 644 can be a solid polymer electrolyte or a separator element used in a liquid electrolyte. The positive electrode 636 and/or the negative electrode 642 may include separately identifiable current collectors. The rolled electrodes 636, 642 and the 4 separator 644 are placed in a sealed container 646 connecting the positive contact 632 and the negative contact 638, so that the electrical insulation barrier 648 separates the positive contact 632 and the negative contact 638.

Smaller thin battery structures can be combined in parallel and/or in series. Referring to FIG. 13, battery 680 includes a stack of thin batteries 682 connected in parallel. Adjacent batteries have a common current collector. The positive current collector 684 electrically contacts the positive electrode 686, and the negative current collector 688 electrically contacts the negative electrode 690. The separator 692 is located between the positive electrode 684 and the negative electrode 688.

F. Manufacturing of thin electrodes and batteries

Many different methods can be used to make extremely thin batteries. For example, the nanoparticle can be dispersed to form a dispersion or slurry of nanoparticle. The dispersion may include electroactive nanoparticle, conductive nanoparticle, and binder (if used). A suitable dispersant has a reasonably high vapor pressure so that it evaporates quite quickly after forming the electrode layer. The dispersant is preferably to dissolve the binder so that the binder mixes the particles fairly uniformly. Various organic solvents can be used as dispersants, such as alcohols, ketones, acetonitrile, esters, ethers, and combinations thereof, depending on the specific binder. Surfactants etc. can be used to further disperse the nanoparticle. The formation of nanoparticle dispersions is further described in a US patent application filed by Reit et al. on November 4, 1999, under the title "Particle Dispersions", which is incorporated herein by reference. Generally, the dispersion should contain about 5 wt% solids to about 60 wt% solids.

The particle dispersion can then be coated by various coating techniques. For example, the dispersion can be applied by spray coating or spin coating. For spray coating, the nozzle can be designed to supply a fairly uniform thin coating. Spin coating similarly provides a fairly uniform coating. The volume of the dispersion to be applied should be adjusted to produce the desired layer thickness, and then dried to remove the dispersant.

The spray coating technique can be applied by the use of a mask or the like to form a structure with a desired shape. For example, the formation of a battery integrated into an integrated circuit is described below. Or, without using a mask to form the required structure, the inkjet print head can apply the slurry. Nanoparticle slurry replaces ink. A printing head can be used to form a fairly uniform layer of nanoparticle in the desired shape. Generally, for inkjet applications, the dispersion has a solids concentration of less than about 5% by weight. The viscosity is preferably no more than about 100 cP. Other printing techniques, such as offset printing, can be used similarly to coating nanoparticle dispersions. Similarly, electrophoretic deposition can be used, in which an electric field is applied to the substrate in a dispersion of particles. The particles bind to the substrate due to opposite charges on the surface of the particles.

Using these methods, very thin and very smooth electrodes can be formed. In addition, due to the smoothness of the electrodes, thinner separators are used. For example, by vapor deposition of LIPON, a thin separator/solid electrolyte can be formed. LIPON can Li ₃ PO ₄ The RF magnetron sputtering deposition. The formation of LIPON RF magnetron sputtering with Li _2.9 PO ₃₃ N _0.46 The typical composition. These thin electrodes and separators can be used to form thin batteries.

In order to form the battery structure, the components can be sequentially coated into a coating. It is especially convenient for very thin batteries. Therefore, the first coating is applied to the substrate, which can be a permanent support structure, a temporary support structure from which the battery is later removed, or a battery element (such as a thin metal foil forming a current collector). Suitable permanent support structures include, for example, an insulating layer on a solid support or a thin polymer sheet, thus forming a very flexible battery. The temporary support structure includes, for example, a non-adhesive polymer sheet, such as polytetrafluoroethylene (TEFLON®), from which the battery can be removed to form a battery structure without the additional weight and body of the substrate. After all the required layers are deposited, if the shape is to be changed by the coating form, the battery structure can be formed into the required shape by, for example, rolling.

G. Manufacturing of integrated battery components

The thin battery structure that can be formed from nano-particles is particularly convenient for the formation of an integrated battery that forms an integrated component of an integrated circuit. The formation of an integrated battery formed by a continuous layer of vapor deposition is described in Park et al. in Electrochemical and Solid-State Letters, Vol. 2, No. 2, pp. 55-59 (1999), titled "All-Solid-State" Lithium Thin-Film Rechargeable Battery with Lithium Manganese Oxide", which is incorporated herein as a reference. The use of nanoparticle has the unique advantage of manipulating the composition and crystallinity of the electroactive material before the battery element is formed. The manipulation of the granular form is far more diverse than the manipulation after the electrode is formed. In addition, the total composition of electrodes, including the presence of conductive particles, can be manipulated to provide electrodes with better characteristics. At any time after the particles are deposited, some particle sintering can be performed.

The integrated thin battery structure has the general characteristics shown in Figures 14 and 15. Referring to FIGS. 14 and 15, the integrated battery 700 is located on the substrate 702. The battery 700 includes a positive current 704 and a negative current collector 706 that extend beyond the surface of the substrate 702. The positive current collector 704 contacts the positive electrode 708, and the negative current collector 706 contacts the negative electrode 710. The separator 712 separates the positive electrode 708 and the negative electrode 710. The thin layer structure of the integrated battery 700 can be formed by the above-mentioned method.

The integrated battery structure can be used as a direct or backup power source for integrated microelectronics. Other microelectronic components 714 can be placed on the upper surface 716 of the substrate 702 and/or on the lower surface 718 of the substrate 702, wherein the microelectronic components are connected to the battery 700 via electrical contacts 720 extending through the substrate 702.

Due to the relatively high mass surface of the nanoparticle electroactive particles and the high surface area of the electrode, the thin battery structure has a relatively high current density. In order to take advantage of the high current density in the circuit and the battery and further reduce any resistance, multiple contacts can be completed between the circuit and the battery structure. Such a structure with multiple contacts is shown in Figure 16. The integrated battery 730 includes a plurality of positive collector contacts 732 and negative current collector contacts 734. The current collector contacts 732, 734 can be connected to one or more different integrated circuits 736.

Example Example 1-The composition of a smooth electrode with electroactive nanoparticle

This example demonstrates the production of very smooth battery electrodes made of electroactive nano-particles.

The use of laser pyrolysis and subsequent heat treatment to produce lithium manganese oxide nanoparticle, especially in accordance with the U.S. Patent Application Serial No. 09/334,203 of Kumar et al., which is under examination and co-assignment, and the title of the invention is "Reaction MethodsFor Producing Ternary Particles" The steps described are incorporated herein as reference. The lithium manganese oxide nanoparticles have an average diameter of about 25 nanometers and a narrow particle size distribution. The distribution of lithium manganese oxide nanoparticles is shown in Figure 17. Lithium manganese oxide nanoparticle is a suitable material for the formation of secondary batteries.

Lithium manganese oxide nanoparticle combined graphite powder (Chuetsu Grapbite Works, Osaka, Japan) with an average particle size of about 2 microns is used as a conductive diluent. The dry powder was blended with a 12% by weight dispersion of poly(vinylidene fluoride) (PVdF) in a solvent of n-methylpyrrolidone using a mortar and pestle. PVdF acts as a binder. The solids in the resulting formulation are 60% by weight of lithium manganese oxide, 30% by weight of carbon (approximately equal to the amount of graphite and carbon black), and 10% by weight of PVdF. A disc with a higher concentration of lithium manganese oxide is obtained. The dispersion is mixed uniformly and coated on the stainless steel foil with a thickness of 200 microns.

Cut approximately 2 cm2 dish from the coated foil, dry and compress it to 5,000 pounds on 2 cm2 to make the coating dense. The compressed dish is vacuum dried and weighed. After drying, the dish has a thickness of about 30 microns. Repeat this step using commercially available lithium manganese oxide with a relatively standard particle size. After weighing the vacuum-dried pellets, the samples were analyzed by scanning electron microscope and atomic force microscope.

The scanning electron micrograph of the electrode made of lithium manganese oxide nanoparticle is shown in FIG. 18. The picture of the same material is enlarged 100 times in Fig. 19. For comparison, a scanning electron micrograph of an electrode made of commercially available lithium manganese oxide powder is shown in FIG. 20. The surface of FIG. 20 can be seen to be much rougher than the surface of FIG. 18.

The specific embodiments described above are intended to be descriptive and not restrictive. Additional specific embodiments are within the scope of the following patent applications. Although the present invention has been described with reference to the preferred specific embodiments, those familiar with the art should be able to change the form and details without departing from the spirit and scope of the present invention.