Charging system of electric vehicle and method for charging electric vehicle

FIELD OF THE INVENTION

The present invention relates to a charging system of an electric vehicle and a method for charging the electric vehicle. More particularly, the present invention relates to a charging system of an electric vehicle and the method for charging the electric vehicle using a smart card for battery management when charging the battery.

BACKGROUND OF THE INVENTION

An electric vehicle, also referred to as an electric drive vehicle, is a moving vehicle using one or more electric motors as driving system. Unlike petroleum-based transportations which are moved by the energy from gasoline, the electric vehicles use electric power as their propulsion. They won't generate waste gas. Noise is also less. During the last few decades, increased concern over the environmental impact of the petroleum-based transportation, along with the spectre of peak oil, has led to renewed interest in electric transportation. Electric power for electric vehicles can be generated from a wide range of sources, including fossil fuels, nuclear power, and renewable sources such as tidal power, solar power, and wind or any combination of those.

In the past, an electric vehicle consumes huge electric power due to their power system. The electric power can only be transmitted to the car through overhead lines. This infrastructure makes the electric vehicles impossible to be popular. Only some of public transportations have access to it. Routes of the public transportation are strictly limited by the lined arrangement. With the development in power systems of electric vehicles, especially in batteries, the electric vehicles become a future star and more and more sources are devoted in this field.

People are used to their existing life experience. Hence, a system for charging the batteries of the electric vehicles should be as convenient as a gas station system. When batteries of an electric car are in low battery, people can drive the car to a nearby charging station and get the batteries charged or replaced with full charged ones. Preferably, the batteries can be charged during off-peak period when cost of charge of electricity is lowest. Meanwhile, with a device to manage batteries that are used in the car, people can always know the status of the batteries and mechanics of the stations can trace the batteries for maintenance. Since the batteries are expensive, if the batteries are stolen and they can be easily found, it will be a great help for the car owners. However, the requirements mentioned above need an integrated system to fulfill.

U.S. Pat. No. 7,679,366 discloses a method for recharging an electric storage battery in a charging system of an electric vehicle. Please refer to <figref idref="DRAWINGS">FIG. 1</figref>. Power comes from an electric utility power grid. '366 Patent includes determining the length of time required to recharge the battery, determining the desired time when the recharge is to be completed, transmitting to the electric power utility the length of time required to recharge the battery and the desired time, and recharging the battery from the utility grid during a period when projected load demand is lower than peak demand and ending no later than the desired time.

'366 Patent is for hybrid electric vehicles, not for pure electric vehicles. The method only focuses on an optimal way to charge the batteries through a day so that time for low demand of electricity can be fully applied and charging cost can be minimal. However, no solution for battery management is mentioned.

Another prior art is disclosed in U.S. Pat. No. 7,795,841. Please refer to <figref idref="DRAWINGS">FIG. 2</figref>. '841 Patent provides a charging system and method capable of starting or stopping charging a battery of a vehicle at a convenient time. A portable device and a vehicle unit can communicate with each other. A user is determined to be away from the vehicle based on a result of communication between the portable device and the vehicle unit. A charging ECU starts charging a battery when the user is away from the vehicle. Charging of the battery can be started when the user is assumed to have stopped using the vehicle and will not use the vehicle for a period of time. When the user is determined to be close to the vehicle it is assumed that use of the vehicle will be resumed at which point the system instructs the charging of the battery to be stopped. The system allows the vehicle to be ready for use.

'841 Patent is also applied to hybrid electric vehicles. It uses the portable device to control the process of charging. However, the portable device can not inform the user of charging or battery status. Charging schedule can not be set to utilize off-peak time of electric power source to save cost.

None of the prior arts can provide an integrated system and method for charging the electric vehicle using a smart card for battery management when charging the battery, preventing the batteries from being stolen, or save charging expense for users. Hence, an integrated system and a method for charging electric vehicles having above features are still desired.

SUMMARY OF THE INVENTION

This paragraph extracts and compiles some features of the present invention; other features will be disclosed in the follow-up paragraphs. It is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims.

In accordance with an aspect of the present invention, a charging system of an electric vehicle, comprises: a smart card having a user identification (UID) for identifying a user of the electric vehicle; a first rechargeable battery having first battery information and stored with the UID while installed in the electric vehicle, for providing electric power to the electric vehicle; a second rechargeable battery having second battery information and stored with the UID while the first rechargeable battery in low battery is replaced with the second rechargeable battery; and a charging station, comprising: a controlling module for confirming that the first rechargeable battery is stored with the UID and then allowing replacement of the first rechargeable battery with the second rechargeable battery; an updating unit for writing the UID to the second rechargeable battery while the first rechargeable battery is replaced with the second rechargeable battery; and a charging set for charging the first and second rechargeable batteries.

Preferably, the first and second rechargeable batteries each has a unique and unchangeable battery serial number.

Preferably, the first and second battery information each comprises charging state, lifetime, cycle count and health state of the rechargeable battery.

Preferably, the charging system further includes a transmitter for transmitting the charging state, lifetime, cycle count and health state of the rechargeable battery, and UID to a remote computer via local area network (LAN), wide area network (WAN), wireless LAN or wireless WAN.

Preferably, the remote computer is stored with the UID, user name, user telephone number, and license plate number of the electric vehicle.

Preferably, the charging system further includes a billing unit for billing the user while replacing the first rechargeable battery with the second rechargeable battery.

Preferably, the charging system further includes a notifying unit for notifying the user update of battery information via instant messaging service, short message service (SMS) or email.

In accordance with an aspect of the present invention, in an electric vehicle having a first rechargeable battery, a method for charging the electric vehicle, comprises the steps of: storing in a smart card a user identification (UID) for identifying a user of the electric vehicle; determining whether the first rechargeable battery is stored with the UID; replacing the first rechargeable battery in low battery with a second rechargeable battery; and writing the UID to the second rechargeable battery while the first rechargeable battery is replaced with the second rechargeable battery.

Preferably, the first and second rechargeable batteries each has a unique and unchangeable battery serial number.

Preferably, the first and second rechargeable battery each has battery information which comprises charging state, lifetime, cycle count and health state of the rechargeable battery.

Preferably, the charging method further includes a step of notifying the user update of the battery information via instant messaging service, short message service (SMS) or email.

Preferably, the charging method further includes a step of transmitting the charging state, lifetime, cycle count and health state of the rechargeable battery, and UID to a remote computer via local area network (LAN), wide area network (WAN), wireless LAN or wireless WAN.

Preferably, the remote computer is stored with the UID, user name, user telephone number, and license plate number of the electric vehicle.

Preferably, the charging method further includes a step of billing the user while replacing the first rechargeable battery with the second rechargeable battery.

BRIEF DESCRIPTION OF THE DRAWINGS

<figref idref="DRAWINGS">FIG. 1</figref> shows a prior art of a charging system.

<figref idref="DRAWINGS">FIG. 2</figref> shows another prior art of a charging system.

<figref idref="DRAWINGS">FIG. 3</figref> illustrates an embodiment of the present invention.

<figref idref="DRAWINGS">FIG. 4</figref> describes detailed structure of a charging station in the embodiment.

<figref idref="DRAWINGS">FIG. 5</figref> describes another detailed structure of the charging station in the embodiment.

<figref idref="DRAWINGS">FIG. 6</figref> describes still another detailed structure of the charging station in the embodiment.

<figref idref="DRAWINGS">FIG. 7</figref> is a flowchart of a charging method according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described more specifically with reference to the following embodiment. Please refer to <figref idref="DRAWINGS">FIG. 3</figref> to <figref idref="DRAWINGS">FIG. 7</figref>. <figref idref="DRAWINGS">FIG. 3</figref> to <figref idref="DRAWINGS">FIG. 6</figref> illustrate a charging system <b>100</b> of an electric vehicle <b>200</b> and detailed structure of the charging system <b>100</b>. <figref idref="DRAWINGS">FIG. 7</figref> is a flowchart showing how the charging system <b>100</b> operates.

Please see <figref idref="DRAWINGS">FIG. 3</figref> first. The charging system <b>100</b> is composed of a first rechargeable battery <b>202</b>, a second rechargeable battery <b>204</b>, a smart card <b>300</b> and a charging station <b>400</b>. The smart card <b>300</b> has a user identification (UID) for identifying a user of the electric vehicle <b>200</b>. The smart card <b>300</b> can only be used for the electric vehicle <b>200</b>, and therefore, if the user buys a new electric vehicle, the smart card <b>300</b> can not be used for the new electric vehicle and a new smart card is needed.

The first rechargeable battery <b>202</b> contains first battery information and is stored with the UID while installed in the electric vehicle <b>200</b> for providing electric power to the electric vehicle <b>200</b>. The second rechargeable battery <b>204</b> has second battery information. It is used for replacing the first rechargeable battery <b>202</b> when the first rechargeable battery <b>202</b> is in low battery (solid arrows in <figref idref="DRAWINGS">FIG. 3</figref>). According to the spirit of the invention, the first rechargeable battery <b>202</b> in low battery is exchanged with the fully charged second rechargeable battery <b>204</b>. The first battery information and the second battery information each comprises charging state, lifetime, cycle count and health state of the first rechargeable battery <b>202</b> or the second rechargeable battery <b>204</b>.

According to the spirit of the present invention, any kind of smart card can be applied. In the embodiment, the smart card <b>300</b> conforms to ISO7810 and has near field communication (NFC) function for data transmission. Only when a smart card having a UID that matches with the electric vehicle <b>200</b>, can the battery be exchanged. Hence, if a person doesn't own the smart card <b>300</b> or the electric vehicle <b>200</b> and takes the electric vehicle <b>200</b> or the first rechargeable battery <b>202</b> to charge, the charging station <b>400</b> will deny battery exchange and inform the original owner of this issue.

In order to describe the charging station <b>400</b> in detail, please further refer to <figref idref="DRAWINGS">FIG. 4</figref>. The charging station <b>400</b> comprises a controlling module <b>404</b>, an updating unit <b>406</b> and a charging set <b>408</b>.

The controlling module <b>404</b> confirms that the first rechargeable battery <b>202</b> is stored with the UID and then allows replacement of the first rechargeable battery <b>202</b> with the second rechargeable battery <b>204</b>. When the smart card <b>300</b> gets close to 5-10 cm from the controlling module <b>404</b>, the confirming process proceeds (dashed arrows in <figref idref="DRAWINGS">FIG. 3</figref>).

The updating unit <b>406</b> writes the UID to the second rechargeable battery <b>204</b> while the first rechargeable battery <b>202</b> is replaced with the second rechargeable battery <b>204</b>. Like the controlling module <b>404</b>, the updating unit <b>406</b> is located in the charging station <b>400</b> where the smart card <b>300</b> can get close up to 5-10 cm for completing writing process.

The charging set <b>408</b> is used for charging the first and second rechargeable batteries <b>202</b> and <b>204</b>. In this embodiment, the second rechargeable battery <b>204</b> is charged before battery exchange. Of course, after the first rechargeable battery <b>202</b> is uninstalled from the electric vehicle <b>200</b>, the charging set <b>408</b> will then charge the first rechargeable battery <b>202</b>. By battery exchange, the first and second rechargeable batteries <b>202</b> and <b>204</b> can be charged anytime. Therefore, the first and second rechargeable batteries <b>202</b> and <b>204</b> are usually charged during off-peak period of electricity supply when charge of electricity is lowest such that cost of charging can be reduced.

Outside of the charging station <b>400</b>, there is a display unit <b>410</b>. It displays the first battery information and the second battery information. If there is something wrong with charging processes, error information can be clearly displayed for check.

Please refer to <figref idref="DRAWINGS">FIG. 5</figref>. According to the spirit of the present invention, the charging system <b>100</b> further comprises a transmitter <b>412</b>. The transmitter <b>412</b> retrieves battery information from the rechargeable battery while the charging set <b>408</b> is connected to the rechargeable battery and transmits the charging state, lifetime, cycle count and health state of the first and second rechargeable batteries <b>202</b> and <b>204</b>, and UID to a remote computer <b>450</b> via local area network (LAN), wide area network (WAN), wireless LAN or wireless WAN. Management job can be done outside of the charging station <b>400</b>. The transmitting method can be wired or wireless communication. The remote computer <b>450</b> is also stored with the UID, user name, user telephone number, and license plate number of the electric vehicle <b>200</b>.

Additionally, the charging system <b>100</b> further comprises a notifying unit <b>414</b>. It can notify the user update of battery information via instant messaging service, short message service (SMS) or email. Instant messaging service includes skype, facebook, msn, and so on. The SMS is sent via telecommunications. The email is sent via local area network (LAN), wide area network (WAN), wireless LAN or wireless WAN. The notifying unit <b>414</b> is connected to the remote computer <b>450</b> and can be either inside or outside the charging station <b>400</b>.

The charging system <b>100</b> can also have a billing unit <b>416</b> for billing the user while replacing the first rechargeable battery <b>202</b> with the second rechargeable battery <b>204</b>. All costs can be summed up to the user. In the present invention, cost can be paid by a credit card or be deducted from the smart card which is used as a prepaid card.

Moreover, the first rechargeable battery <b>202</b> and the second rechargeable battery <b>204</b> each have a unique and unchangeable battery serial number. Therefore, even though UID of a rechargeable battery changes every time during battery exchange, the rechargeable battery can still be traced by its battery serial number. By this way, the rechargeable battery can be easily found if it is stolen. Furthermore, if the rechargeable battery is stolen, then the unchangeable battery serial number of the stolen rechargeable battery will be listed in a “black list” in the remote computer <b>450</b>. By this way, the stolen rechargeable battery can be easily found since the stolen rechargeable battery has to be charged at the charging station <b>400</b> which has access to the “black list” of the remote computer <b>450</b>.

Please see <figref idref="DRAWINGS">FIG. 7</figref>. The method for charging the electric vehicle <b>200</b> by the charging system <b>100</b> is described below. First, the smart card <b>300</b> is stored with the UID for identifying a user of the electric vehicle <b>200</b> (Step S<b>101</b>). Then, whether the first rechargeable battery is stored with the UID is determined (Step S<b>102</b>). If the first rechargeable battery <b>202</b> is not stored with the UID, then battery exchange request will be denied and the original owner will be informed of this issue (Step S<b>103</b>). If the first rechargeable battery <b>202</b> is confirmed stored with the UID, then battery exchange request will be accepted and the first rechargeable battery <b>202</b> in low battery will be replaced with the second rechargeable battery <b>204</b> (Step S<b>104</b>). Subsequently, the UID will be written to the second rechargeable battery <b>204</b> while the first rechargeable battery <b>202</b> is replaced with the second rechargeable battery <b>204</b> (Step S<b>105</b>). Finally, the first rechargeable battery <b>202</b> is charged (Step S<b>106</b>).

According to the spirit of the present invention, the method may further include the following steps:

1. The charging state, lifetime, cycle count and health state of the rechargeable batteries <b>202</b> and <b>204</b>, and UID are transmitted to the remote computer <b>450</b> via local area network (LAN), wide area network (WAN), wireless LAN or wireless WAN. This step can be done after Step S<b>106</b>.

2. The first user information, the first battery information, and the second battery information are displayed. This step can be done among any step after Step S<b>102</b>.

3. The user is billed after replacement of the first rechargeable battery with the second rechargeable battery. This step can be done between Step S<b>104</b> and Step S<b>106</b>.

4. The user is notified of update of battery information via instant messaging service, short message service (SMS) or email. This step can be done between Step S<b>104</b> and Step S<b>106</b>.

While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.