Power Supply System, Vehicle with the Same and Temperature Managing Method

• US 20090179616A1
• Filed: 07/05/2007
• Published: 07/16/2009
• Est. Priority Date: 07/10/2006
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Komae, Masanobu, Tsuchiya, Kenji, Ishikawa, Tetsuhiro, Ichikawa, Shinji, Yano, Tsuyoshi
• Granted Patent: US 7,795,844 B2
• Time in Patent Office: Days
• US Class Current: 320/134
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/0053 relating to fuel cells
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/26 by cooling
• CPC Class Codes: B60L 58/27 by heating
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: F02N 2011/0888 DC/DC converters
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/443 in response to temperature
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/615 Heating or keeping warm
• CPC Class Codes: H01M 10/625 Vehicles
• CPC Class Codes: H01M 10/637 : characterised by the use of reversible temperature-sensitive devices, e.g. NTC, PTC or bimetal devices; characterised by control of the internal current flowing through the cells, e.g. by switching means for preventing undesired use or discharge H01M50/572
• CPC Class Codes: H01M 16/00 : Structural combinations of different types of electrochemical generators
• CPC Class Codes: H02J 7/1423 : with multiple batteries
• CPC Class Codes: H02J 7/1492 : by means of controlling devices between the generator output and the battery
• CPC Class Codes: H02M 3/1582 : Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: H02M 3/1584 : with a plurality of power processing stages connected in parallel
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/40 : Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A request determining unit compares a battery temperature of a battery unit with a predetermined temperature management value, and produces a heating request or a cooling request when a temperature deviation of a predetermined threshold is present between them. A current direction determining unit determines, based on thermal reaction characteristics of the battery unit, in which one of a direction on a charge side and a direction on a discharge side a current is to be passed for responding to the heating request or the cooling request. A target current value determining unit determines a target current value related to the charge/discharge determined by the current direction determining unit. A current control unit produces a switching instruction for matching a battery current of the battery unit with the target current value provided from a selecting unit.

Claims

1. A power supply system having a plurality of battery units each being rechargeable, and comprising:

a power supply line allowing supply and reception of an electric power between a load device and said power supply system; and

a plurality of charge/discharge control units arranged between said plurality of battery units and said power line, respectively, and each being capable of controlling charging/discharging of the corresponding battery unit, wherein

said plurality of battery units includes at least one first battery unit handled as a temperature management target, and a residual second battery unit,

said first battery unit includes a chemical cell having thermal reaction characteristics changing a thermal reaction caused by each of charging and discharging between a heat generating reaction and a heat absorbing reaction depending on a state of charge, and

said power supply system further comprises;

a temperature obtaining unit obtaining a temperature of said first battery unit;

an SOC obtaining unit obtaining a state of charge of said first battery unit;

a request producing unit producing one of a heating request and a cooling request for said first battery unit based on the temperature obtained by said temperature obtaining unit;

a current direction determining unit determining, for the battery unit corresponding to one of said heating request and said cooling request produced by said request producing unit, in which one of a direction on a charge side and a direction on a discharge side a current is to be passed for responding to one of said heating request and said cooling request based on said thermal reaction characteristics, from the state of charge obtained by said SOC obtaining unit; and

a control instruction producing unit providing a control instruction to each of said plurality of charge/discharge control units for passing the current in the direction determined by said current direction determining unit.

2. The power supply system according to claim 1, further comprising:

a target current value determining unit determining, based on the temperature of said first battery unit, a target current value for passing the current on one of the charge side and the discharge side determined by said current direction determining unit.

3. The power supply system according to claim 2, wherein

said control instruction producing unit provides said control instruction to said charge/discharge control unit corresponding to said first battery unit such that a current value of said first battery unit attains said target current value determined by said target current value determining unit.

4. The power supply system according to claim 3, wherein

said control instruction producing unit provides said control instruction to said charge/discharge control unit corresponding to said second battery unit such that the power corresponding to a difference between a sum of the charge/discharge power of said first battery unit and a power required by said load device is supplied.

5. The power supply system according to claim 2, wherein

said plurality of battery units consist of one of said first battery unit and one of said second battery unit, and

said control instruction producing unit provides said control instruction to said charge/discharge control unit corresponding to said second battery unit such that the power corresponding to a difference between the charge/discharge power of said first battery unit corresponding to said target current value determined by said target current value determining unit and a power required from said load device is supplied.

6. The power supply system according to claim 2, wherein

said target current value determining unit determines said target current value with reference to predetermined resistive heat generation characteristics representing a correlation between the current flowing through said first battery unit and a quantity of generated heat.

7. The power supply system according to claim 2, further comprising:

a current value restricting unit restricting said target current value determined by said target current value determining unit for the purpose of keeping the output voltage of said first battery unit at or above a predetermined voltage value based on predetermined output voltage characteristics representing a correlation between the current flowing through said first battery unit and an output voltage, when said request producing unit produces said heating request.

8. The power supply system according to claim 1, wherein

said first battery unit includes a lithium ion battery.

9. A vehicle comprising:

a power supply system having a plurality of battery units each being rechargeable; and

a drive power generating unit receiving an electric power from said power supply system and generating a drive power, wherein

said power supply system comprising;

a power supply line allowing supply and reception of an electric power between said drive power generating unit and said power supply system, and

a plurality of charge/discharge control units arranged between said plurality of battery units and said power line, respectively, and each being capable of controlling charging/discharging of the corresponding battery unit;

said plurality of battery units includes at least one first battery unit handled as a temperature management target, and a residual second battery unit;

said first battery unit includes a chemical cell having thermal reaction characteristics changing a thermal reaction caused by each of charging and discharging between a heat generating reaction and a heat absorbing reaction depending on a state of charge; and

said power supply system further comprises;

a temperature obtaining unit obtaining a temperature of said first battery unit;

an SOC obtaining unit obtaining a state of charge of said first battery unit;

a request producing unit producing one of a heating request and a cooling request for said first battery unit based on the temperature obtained by said temperature obtaining unit;

a current direction determining unit determining, for the battery unit corresponding to one of heating request and said cooling request produced by said request producing unit, in which one of a direction on a charge side and a direction on a discharge side a current is to be passed for responding to one of said heating request and said cooling request based on said thermal reaction characteristics, from the state of charge obtained by said SOC obtaining unit; and

a control instruction producing unit providing a control instruction to each of said plurality of charge/discharge control units for passing the current in the direction determined by said current direction determining unit.

10. The vehicle according to claim 9, wherein

said power supply system further comprises a target current value determining unit determining, based on the temperature of said first battery unit, a target current value for passing the current on one of the charge side and the discharge side determined by said current direction determining unit.

11. The vehicle according to claim 10, wherein

said control instruction producing unit provides said control instruction to said charge/discharge control unit corresponding to said first battery unit such that a current value of said first battery unit attains said target current value determined by said target current value determining unit.

12. The vehicle according to claim 11, wherein

said control instruction producing unit provides said control instruction to said charge/discharge control unit corresponding to said second battery unit such that the power corresponding to a difference between a sum of the charge/discharge power of said first battery unit and a power required by said drive power generating unit is supplied.

13. The vehicle according to claim 10, wherein

said plurality of battery units consist of one of said first battery unit and one of said second battery unit, and

said control instruction producing unit provides said control instruction to said charge/discharge control unit corresponding to said second battery unit such that the power corresponding to a difference between the charge/discharge power of said first battery unit corresponding to said target current value determined by said target current value determining unit and a power required by said drive power generating unit is supplied.

14. The vehicle according to claim 10, wherein

said target current value determining unit determines said target current value with reference to predetermined resistive heat generation characteristics representing a correlation between the current flowing through said first battery unit and a quantity of generated heat.

15. The vehicle according to claim 10, further comprising:

a current value restricting unit restricting said target current value determined by said target current value determining unit for the purpose of keeping the output voltage of said first battery unit at or above a predetermined voltage value based on predetermined output voltage characteristics representing a correlation between the current flowing through said first battery unit and an output voltage, when said request producing unit produces said heating request.

16. The vehicle according to claim 9, wherein

said first battery unit includes a lithium ion battery.

17. A temperature managing method for a battery unit in a power supply system having a plurality of battery units each being rechargeable, wherein

said power supply system includes:

a power supply line allowing supply and reception of an electric power between a load device and said power supply system; and

a plurality of charge/discharge control units arranged between said plurality of battery units and said power line, respectively, and each being capable of controlling charging/discharging of the corresponding battery unit;

said plurality of battery units includes at least one first battery unit handled as a temperature management target, and a residual second battery unit,

said first battery unit includes a chemical cell having thermal reaction characteristics changing a thermal reaction caused by each of charging and discharging between a heat generating reaction and a heat absorbing reaction depending on a state of charge, and

said temperature managing method comprises;

a temperature obtaining step of obtaining a temperature of said first battery unit;

an SOC obtaining step of obtaining a state of charge of said first battery unit;

a request producing step of producing one of a heating request and a cooling request for said first battery unit based on the temperature obtained in said temperature obtaining step;

a current direction determining step of determining, for the battery unit corresponding to one of said heating request and said cooling request produced in said request producing step, in which one of a direction on a charge side and a direction on a discharge side a current is to be passed for responding to one of said heating request and said cooling request based on said thermal reaction characteristics, from the state of charge obtained in said SOC obtaining step; and

a control instruction producing step of providing a control instruction to each of said plurality of charge/discharge control units for passing the current in the direction determined in said current direction determining step.

18. The temperature managing method according to claim 17, further comprising:

a target current value determining step of determining, based on the temperature of said first battery unit, a target current value for passing the current on one of the charge side and the discharge side determined in said current direction determining step.

19. The temperature managing method according to claim 18, wherein

said control instruction producing step provides said control instruction to said charge/discharge control unit corresponding to said first battery unit such that a current value of said first battery unit attains said target current value determined in said target current value determining step.

20. The temperature managing method according to claim 19, wherein

said control instruction producing step includes providing said control instruction to said charge/discharge control unit corresponding to said second battery unit such that the power corresponding to a difference between a sum of the charge/discharge power of said first battery unit and a power required by said load device is supplied.

21. The temperature managing method according to claim 18, wherein

said plurality of battery units consist of one of said first battery unit and one of said second battery unit, and

said control instruction producing step includes providing said control instruction to said charge/discharge control unit corresponding to said second battery unit such that the power corresponding to a difference between the charge/discharge power of said first battery unit corresponding to said target current value determined in said target current value determining unit and a power required by said load device is supplied.

22. The temperature managing method according to claim 18, wherein

said target current value determining step includes determining said target current value with reference to predetermined resistive heat generation characteristics representing a correlation between the current flowing through said first battery unit and a quantity of generated heat.

23. The temperature managing method according to claim 18, further comprising:

a current value restricting step of restricting said target current value determined in said target current value determining step for the purpose of keeping the output voltage of said first battery unit at or above a predetermined voltage value based on predetermined output voltage characteristics representing a correlation between the current flowing through said first battery unit and an output voltage, when said request producing step produces said heating request.