ELECTRIC SYSTEM, CHARGING DEVICE AND CHARGING METHOD FOR ELECTRIC SYSTEM

• US 20100134065A1
• Filed: 06/06/2008
• Published: 06/03/2010
• Est. Priority Date: 06/11/2007
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toyota Jidoshokki, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Kabushiki Kaisha Toyota Jidoshokki, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Iida, Takahide
• Granted Patent: US 8,237,398 B2
• Time in Patent Office: Days
• US Class Current: 320/103
• CPC Class Codes: B60L 2210/20 AC to AC converters
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 3/12 Recording operating variables ; Monitoring of operating variables
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

An ECU executes a program including the steps of causing a battery pack to discharge when an external power supply is connected to a charger, stopping discharge of the battery pack when a state of charge of the battery pack is reduced to a reset value, and charging the battery pack after the state of charge is reduced to the reset value.

Claims

1. An electric system comprising:

a power storage mechanism for storing electric power; and

a control unit, wherein

said control unit detects connection of said power storage mechanism to an external power supply, automatically causes said power storage mechanism to discharge until a state of charge of said power storage mechanism decreases to a predetermined value upon detecting connection of said power storage mechanism to said external power supply, and causes said power storage mechanism to be charged after discharge of said power storage mechanism until the state of charge of said power storage mechanism decreases to said predetermined value,

said power storage mechanism includes a first power storage mechanism and a second power storage mechanism connected in parallel to each other, and

said control unit causes said first power storage mechanism and said second power storage mechanism to discharge in an alternating manner, and charges, during discharge of one of the power storage mechanisms, electric power supplied from outside said electric system into the other power storage mechanism.

2. The electric system according to claim 1, wherein

said control unit causes electric power discharged from one of the power storage mechanisms to be charged into the other power storage mechanism.

5. The electric system according to claim 1, wherein

said control unit causes said power storage mechanism to discharge such that a rate of reduction in the state of charge of said power storage mechanism varies depending on at least any one of the state of charge and a voltage of said power storage mechanism during discharge of said power storage mechanism.

7. The electric system according to claim 1, wherein

said control unit determines whether to permit or prohibit discharge of said power storage mechanism in accordance with the state of charge of said power storage mechanism.

8. The electric system according to claim 1, wherein

said power storage mechanism is mounted on a vehicle for supplying electric power to a driving source, and

said control unit stores information about discharge of said power storage mechanism until the state of charge of said power storage mechanism decreases to said predetermined value, and controls said power storage mechanism during travel of said vehicle based on said information.

9. The electric system according to claim 1, wherein

said control unit stores information about discharge of said power storage mechanism until the state of charge of said power storage mechanism decreases to said predetermined value during a first period, and causes said power storage mechanism to discharge based on said information when charging said power storage mechanism during a second period later than said first period.

10. The electric system according to claim 1, wherein

said power storage mechanism is a battery.

3. (canceled)

4. (canceled)

6. (canceled)

11. A charging method for an electric system including a power storage mechanism for storing electric power, comprising the steps of:

detecting connection of said power storage mechanism to an external power supply;

automatically causing said power storage mechanism to discharge until a state of charge of said power storage mechanism decreases to a predetermined value upon detecting connection of said power storage mechanism to said external power supply;

charging said power storage mechanism after discharge of said power storage mechanism until the state of charge of said power storage mechanism decreases to said predetermined value, wherein

said power storage mechanism includes a first power storage mechanism and a second power storage mechanism connected in parallel to each other,

said step of causing said power storage mechanism to discharge includes the step of causing said first power storage mechanism and said second power storage mechanism to discharge in an alternating manner, and said charging method further comprises the step of

charging, during discharge of one of the power storage mechanisms, electric power supplied from outside said electric system into the other power storage mechanism.

12. The charging method for an electric system according to claim 11, comprising the step of charging electric power discharged from one of the power storage mechanisms into the other power storage mechanism.

15. The charging method for an electric system according to claim 11, wherein

said step of causing said power storage mechanism to discharge includes the step of causing said power storage mechanism to discharge such that a rate of reduction in the state of charge of said power storage mechanism varies depending on at least any one of the state of charge and a voltage of said power storage mechanism during discharge of said power storage mechanism.

17. The charging method for an electric system according to claim 11, further comprising the step of determining whether to permit or prohibit discharge of said power storage mechanism in accordance with the state of charge of said power storage mechanism.

18. The charging method for an electric system according to claim 11, wherein

said power storage mechanism is mounted on a vehicle for supplying electric power to a driving source, and

said charging method further comprises the steps of storing information about discharge of said power storage mechanism until the state of charge of said power storage mechanism decreases to said predetermined value, and controlling said power storage mechanism during travel of said vehicle based on said information.

19. The charging method for an electric system according to claim 11, further comprising the step of storing information about discharge of said power storage mechanism until the state of charge of said power storage mechanism decreases to said predetermined value during a first period, wherein

said step of causing said power storage mechanism to discharge includes the step of causing said power storage mechanism to discharge based on said information when charging said power storage mechanism during a second period later than said first period.

20. The charging method for an electric system according to claim 11, wherein

said power storage mechanism is a battery.

13. (canceled)

14. (canceled)

16. (canceled)

21. A charging device for an electric system including a power storage mechanism for storing electric power, comprising:

means for detecting connection of said power storage mechanism to an external power supply;

discharge means for automatically causing said power storage mechanism to discharge until a state of charge of said power storage mechanism decreases to a predetermined value upon detecting connection of said power storage mechanism to said external power supply;

means for charging said power storage mechanism after discharge of said power storage mechanism until the state of charge of said power storage mechanism decreases to said predetermined value, wherein

said power storage mechanism includes a first power storage mechanism and a second power storage mechanism connected in parallel to each other,

said discharge means includes means for causing said first power storage mechanism and said second power storage mechanism to discharge in an alternating manner, and said charging device further comprises

means for charging, during discharge of one of the power storage mechanisms, electric power supplied from outside said electric system into the other power storage mechanism.

22-30. -30. (canceled)