Apparatus for controlling temperature of secondary battery, vehicle battery pack, and system and program for heating secondary battery

• US 7,884,577 B2
• Filed: 03/05/2007
• Issued: 02/08/2011
• Est. Priority Date: 03/07/2006
• Status: Active Grant

• Current Assignee: Panasonic EV Energy Company, Limited (Toyota Motor Corporation)
• Original Assignee: Panasonic EV Energy Company, Limited (Toyota Motor Corporation)
• Inventors: Hori, Yasuyuki, Iida, Takuma, Tsutsumi, Masateru, Matsukawa, Yasushi
• Primary Examiner(s): Tso; Edward
• Assistant Examiner(s): WILLIAMS, ARUN C
• Application Number:
  US11/714,415
• Publication Number:
  US 20070210769A1
• Time in Patent Office: 1,436 Days
• Field of Search: 320/150
• US Class Current: 320/150
• CPC Class Codes: B60L 1/08 Methods and devices for control or regulation
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2240/662 Temperature
• CPC Class Codes: B60L 2240/80 Time limits
• CPC Class Codes: B60L 50/64 Constructional details of batteries specially adapted for electric vehicles
• CPC Class Codes: B60L 58/16 responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: B60L 58/27 by heating
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 10/615 Heating or keeping warm
• CPC Class Codes: H01M 10/633 characterised by algorithms, flow charts, software details or the like
• 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 10/6563 with forced flow, e.g. by blowers
• CPC Class Codes: H01M 10/657 by electric or electromagnetic means
• CPC Class Codes: H01M 10/6571 Resistive heaters arrangements for heating the battery by its resistance to the internal current H01M10/637
• CPC Class Codes: H01M 10/66 Heat-exchange relationships between the cells and other systems, e.g. central heating systems or fuel cells
• 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
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles

Abstract

An apparatus, which controls the temperature of a secondary battery formed by combination of a plurality of single cells or a plurality of battery modules each made by series connection of multiple single cells, prevents variations in the temperature or voltage of the single cells or the battery modules, which could otherwise be caused when the secondary battery is heated. A temperature control section controls the quantity of heat by means of which a heater heats a secondary battery formed by combination of a plurality of battery modules made by series connection of multiple single cells. The temperature control section detects a rate of temporal changes in an open circuit voltage of the secondary battery. When a detected rate of temporal changes in open circuit voltage has exceeded a predetermined threshold voltage value, the heater is controlled to thus diminish the quantity of heat used for heating the secondary battery.

Claims

1. A vehicle battery pack equipped with a temperature controller for a secondary battery, comprising:

a heating device for heating a secondary battery formed by combination of a plurality of battery modules;

a temperature detection section for detecting a temperature of the secondary battery;

a voltage change detection section for detecting the change in an open circuit voltage of the secondary battery within a predetermined period of time wherein a voltage change represents a differential value in voltage of a previously detected voltage and a currently detected voltage; and

a heat quantity control section for activating the heating device when a temperature detected by the temperature detection section at the time of startup of the vehicle is a predetermined reference lower-limit temperature required for the secondary battery to exhibit desired recharging-and-discharging capability or less and for suppressing heating operation of the heating device when the voltage change exceeds an allowable value in accordance with the voltage change detected by the voltage change detection section after the heating device has performed heating.

2. The vehicle battery pack equipped with the temperature controller for a secondary battery according to claim 1, wherein the voltage change detection section is for detecting, for every predetermined group of battery modules, the change in the open circuit voltage within a predetermined period of time;

and

the heat quantity control section suppresses and controls heating operation of the heating device when any of the amounts of voltage changes detected every predetermined group of battery modules exceeds the allowable value.

3. The vehicle battery pack equipped with the temperature controller for a secondary battery according to claim 1, wherein the heat quantity control section stops heating operation of the heating device without regard to a relationship between the temperature and the reference lower-limit temperature when the voltage change exceeds the allowable value.

4. The vehicle battery pack equipped with the temperature controller for a secondary battery according to claim 1, wherein, when the amount of voltage change does not exceed the allowable value, the heat quantity control section stops heating operation of the heating device when the temperature does not fall in excess of the reference lower-limit temperature after elapse of a predetermined period of time after heating operation of the heating device.

5. A vehicle battery pack equipped with a temperature controller for a secondary battery, comprising:

a heating device for heating a secondary battery formed by combination of a plurality of battery modules;

a temperature detection section for detecting a temperature of the secondary battery; and

a heat quantity control section for the heating device to operate when the temperature detected by the temperature detection section at the time of startup of the vehicle is lower than or equal to a predetermined reference lower-limit temperature required for the secondary battery to exhibit desired recharging-and-discharging capability and suppressing the heating operation of the heating device when a temperature change between a previous temperature and the temperature detected by the temperature detection section exceeds an allowable threshold differential temperature within a predetermined period of time after starting of the heating operation of the heating device.

6. The vehicle battery pack equipped with a temperature controller for a secondary battery according to claim 5, wherein the temperature detection section detects temperatures of the plurality of battery modules;

and

the heat quantity control section suppresses heating operation of the heating device when any of the temperature changes in the plurality of battery modules exceeds the allowable value.

7. The vehicle battery pack equipped with a temperature controller for a secondary battery according to claim 5, wherein the heat quantity control section stops heating operation of the heating device regardless of a relationship between the temperature and the reference lower-limit value when the temperature change exceeds the allowable value.

8. The vehicle battery pack equipped with a temperature controller for a secondary battery according to claim 5, wherein the heat quantity control section stops heating operation of the heating device when the temperature change does not exceed the allowable value and when the temperature does not fall in excess of the reference lower-limit temperature after elapse of a predetermined period of time after heating operation of the heating device.