Discharge control device for secondary battery

• US 9,136,723 B2
• Filed: 04/14/2009
• Issued: 09/15/2015
• Est. Priority Date: 05/13/2008
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Izumi, Junta
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): GRANT, ROBERT J
• Application Number:
  US12/991,341
• Publication Number:
  US 20110057618A1
• Time in Patent Office: 2,345 Days
• Field of Search: 320/129
• US Class Current: 1/1
• CPC Class Codes: B60K 6/28 characterised by the electric energy storing means, e.g. batteries or capacitors
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/486 Operating parameters
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• 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: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2540/16 Ratio selector position
• 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 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/0069 Charging or discharging for charge maintenance, battery initiation or rejuvenation
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• 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

Abstract

The object aims to prevent or reduce the deterioration of a secondary battery by charge with an undue pulse. Disclosed is a discharge control device (100) for a secondary battery, which comprises: a detection unit (110) for detecting the charge of the secondary battery with a pulse having a level equal to or higher than a predetermined level; and a discharge control unit (130) for so controlling that at least one pulse having almost the same level as that of the above-mentioned pulse is discharged from the secondary battery when the charge of the secondary battery with the above-mentioned pulse is detected.

Claims

1. A discharge control device for a lithium ion secondary battery, the discharge control device comprising:

a calculator that calculates an overcharging level based on a temperature and a remaining capacity of the secondary battery, the overcharging level is specified as a level causing degradation of the secondary battery due to a deposition of lithium metal;

a detector that detects whether a level of a pulse for charging the secondary battery is equal to or higher than the overcharging level calculated by the calculator; and

a controller that controls a discharge of one or more pulses from the secondary battery, if the detector detects that the level of the pulse for charging the secondary battery is equal to or higher than the overcharging level, the one or more pulses discharged from the secondary battery have a level substantially identical to that of the pulse for charging the secondary battery.

2. The discharge control device for a secondary battery according to claim 1, wherein, upon detection of charging of the secondary battery with the pulse, the controller controls a discharge of a pulse of the one or more pulses to have a level and duration substantially identical to that of the pulse for charging the secondary battery.

3. The discharge control device for a secondary battery according to claim 1, wherein

the secondary battery is connected to a motor to be driven by power of the secondary battery, and

the controller applies phase control to the motor to thereby discharge the pulse from the secondary battery to the motor.

4. The discharge control device for a secondary battery according to claim 1, wherein, upon detection of charging of the secondary battery with the pulse, the controller controls a discharge of a pulse of the one or more pulses to have a level that is substantially identical to that of the pulse for charging the secondary battery.

5. The discharge control device for a secondary battery according to claim 4, wherein the discharged pulse has a pulse height that is substantially identical to that of the pulse for charging the secondary battery.

6. The discharge control device for a secondary battery according to claim 4, wherein the discharged pulse has peak current value that is substantially identical to that of the pulse for charging the secondary battery.