Method for cold-starting batteries

• US 20050064278A1
• Filed: 09/19/2003
• Published: 03/24/2005
• Est. Priority Date: 09/19/2003
• Status: Abandoned Application

• Current Assignee: Chevron Technology Ventures LLC (Chevron Corp.)
• Original Assignee: Chevron Technology Ventures LLC (Chevron Corp.)
• Inventors: Reichman, Benjamin, Fetcenko, Michael A., Koch, John
• Application Number:
  US10/666,089
• Publication Number:
  US 20050064278A1
• Time in Patent Office: Days
• US Class Current: 429/50
• CPC Class Codes: H01M 10/345 Gastight metal hydride accumulators
• CPC Class Codes: H01M 10/443 in response to temperature
• CPC Class Codes: H01M 10/486 for measuring temperature
• 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 10/647 Prismatic or flat cells, e.g. pouch cells
• CPC Class Codes: H01M 10/651 characterised by parameters specified by a numeric value or mathematical formula, e.g. ratios, sizes or concentrations
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A method of starting a nickel metal hydride battery in cold weather. The method includes the step of discharging the battery through a short circuit.

Claims

1. A method of operating a nickel-metal hydride battery, comprising:

providing a nickel-metal hydride battery;

determining the ambient temperature of said battery; and

setting the state of charge of said battery, said state of charge at least partially dependent upon said ambient temperature.

2. The method of claim 1, wherein setting step comprising the steps of:

if the ambient temperature is below a first temperature, then setting said state of charge to a first value; and

if the ambient temperature is above a second temperature, said second temperature being greater than or equal to said first temperature, then setting said state of charge to a second value less than said first value.

3. The method of claim 2, wherein said second temperature is equal to said first temperature.

4. The method of claim 2, wherein the first value of said state of charge is greater than 70%.

5. The method of claim 2, wherein the first value of said state of charge is between 70% and 90%.

6. The method of claim 4, wherein the second value of said state of charge is less than 60%.

7. The method of claim 5, wherein the second value of said state of charge is between 40% and 60%.

8. A method of operating a nickel-metal hydride battery, comprising:

providing said nickel-metal hydride battery, said battery being at an ambient temperature of −

20°

C. or less; and

converting a portion of the chemical energy of said battery to thermal energy.

9. The method of claim 8, wherein said converting step decreases the charge transfer resistance of said battery.

10. The method of claim 9, wherein said converting step comprises the step of discharging said battery.

11. The method of claim 10, wherein said discharging step comprising the step of applying a short circuit across said battery for a finite period of time.

12. The method of claim 8, wherein said battery is provided having a temperature of −

25°

C. or less.

13. The method of claim 8, wherein said battery is provided having a temperature of −

30°

C. or less.

14. The method of claim 11, wherein said short circuit is applied for 10 seconds or less.

15. A method of operating a nickel-metal hydride battery to apply power to a load, comprising the steps of:

providing said nickel-metal hydride battery;

applying a short circuit across the terminals of said battery for a finite period of time;

after applying said short circuit, electrically coupling said battery to said load.

16. The method of claim 15, wherein said short circuit is applied while said battery is electrically disconnected from said load.

17. The method of claim 15, wherein said load comprises a starting and/or ignition circuitry of a vehicle.

18. The method of claim 15,wherein said load comprises a lighting circuitry of a vehicle.

19. The method of claim 15, wherein said short circuit is applied for 10 seconds or less.