Battery heating system using internal battery resistance

• US 5,362,942 A
• Filed: 08/24/1993
• Issued: 11/08/1994
• Est. Priority Date: 08/24/1993
• Status: Expired due to Term

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Scafidi, Christopher J., Vanderslice, William T. Jr.
• Primary Examiner(s): Reynolds, Bruce A.
• Assistant Examiner(s): Jeffery, John A.
• Application Number:
  US08/110,891
• Time in Patent Office: 441 Days
• Field of Search: 219/209, 219/210, 219/202, 219/200, 219/201, 429/120, 429/62, 320/35, 320/36, 320/31
• US Class Current: 219/209
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 58/25 by controlling the electric load
• CPC Class Codes: B60L 58/27 by heating
• CPC Class Codes: H01M 10/615 Heating or keeping warm
• CPC Class Codes: H01M 10/625 Vehicles
• 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 10/6571 Resistive heaters arrangements for heating the battery by its resistance to the internal current H01M10/637
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H05B 1/023 Industrial applications
• CPC Class Codes: H05B 3/60 Heating arrangements wherein the heating current flows through granular powdered or fluid material, e.g. for salt-bath furnace, electrolytic heating H05B3/38 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A battery heater uses the internal resistance of the battery as the battery heating element. In one embodiment, a DC battery charger and a programmable battery load, is used in a closed loop temperature control system. In another embodiment, a DC battery charger and a resistor or small auxiliary battery heater, is used in a closed loop temperature control system. The programmable load or the small auxiliary battery heater, is enabled during full charge, low temperature conditions. The resistor or small auxiliary heater serves to both heat the battery and draw down the battery charge. In yet another embodiment, an AC heater power supply and a DC battery charger, is coupled to the battery in a closed loop temperature control system.

Claims

1. A method for controlling the temperature of a battery having first and second battery terminals and an internal resistance between said first and second battery terminals, comprising the steps of:

(a) sensing the temperature of said battery to provide a sensed battery temperature;

(b) comparing said sensed battery temperature to a predetermined temperature;

(c) responsive to step (b) indicating that the temperature of said battery is less than said predetermined temperature, conducting a current between said first and second battery terminals through said battery;

(d) sensing the charge level of said battery to provide a sensed battery charge level;

(e) comparing said sensed battery charge level to a predetermined charge level; and

(f) responsive to step (e) indicating that said sensed battery charge level is above said predetermined charge level and responsive to step (b) indicating that the temperature of said battery is less than said predetermined temperature, connecting a load across said first and second battery terminals.

2. A method in accordance with claim 1, comprising the additional steps of:

(g) responsive to step (e) indicating that said sensed battery charge level is above said predetermined charge level and responsive to step (b) indicating that the temperature of said battery is less than said predetermined temperature, timing a predetermined time interval; and

(h) connecting said load across said first and second battery terminals for said predetermined time interval.

3. A method in accordance with claim 2, comprising the additional step of:

(i) disabling said step (c) of conducting a current between said first and second battery terminals through said battery during said predetermined time interval.

4. A method in accordance with claim 3, wherein said load comprises an auxiliary heating element in close proximity with said battery.

5. An apparatus for controlling the temperature of a battery wherein said battery has first and second battery terminals and an internal resistance between said first and second battery terminals, said apparatus comprising:

means for sensing the temperature of said battery to provide a sensed battery temperature;

means for comparing said sensed battery temperatures to a predetermined temperature;

means for conducting a current between said first and second battery terminals through said battery, responsive to said means for comparing the temperature of said sensed battery temperature to said predetermined temperature indicating that the temperature of said battery is less than said predetermined temperature;

means for sensing the charge level of said battery to provide a sensed battery charge level;

means for comparing said sensed battery charge level to a predetermined charge level; and

means for connecting a load across said first and second battery terminals responsive to said means for comparing said sensed battery charge level to said predetermined charge level indicating that said sensed battery charge level is above said predetermined charge level and responsive to said means for comparing said sensed temperature to said predetermined temperature indicating that the temperature of said battery is less than said predetermined temperature.

6. An apparatus in accordance with claim 5, further comprising:

means for timing a predetermined time interval responsive to said means for comparing said sensed battery charge level to said predetermined charge level indicating that said sensed battery charge level is above said predetermined charge level and responsive to said means for comparing said sensed temperature to said predetermined temperature indicating that the temperature of said battery is less than said predetermined temperature; and

means for connecting said load across said first and second battery terminals for said predetermined time interval.

7. An apparatus in accordance with claim 6 further comprising:

means for disabling said means for conducting a current between said first and second battery terminals through said battery during said predetermined time interval.

8. An apparatus in accordance with claim 7, wherein said load comprises an auxiliary heating element in close proximity with said battery.