Method for distnguishing batteries having different chemistries

• US 20080309284A1
• Filed: 06/13/2008
• Published: 12/18/2008
• Est. Priority Date: 06/15/2007
• Status: Active Grant

• Current Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Inventors: Brotto, Daniele C., White, Daniel J., Howard, Geoffrey S., Cunanan, Regina Gracia C., Choksi, Snehal
• Granted Patent: US 7,973,511 B2
• Time in Patent Office: Days
• US Class Current: 320/106
• CPC Class Codes: H02J 7/00041 in response to measured battery parameters, e.g. voltage, current or temperature profile
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries

Abstract

A method is provided for distinguishing between batteries having different chemistry compositions. The method includes: supplying electrical energy to the battery for charging thereof; monitoring a voltage characteristic of the battery periodically during charging, wherein the voltage characteristic varies over time with the state of charge of the battery; and identifying the chemistry composition of the battery based on the voltage characteristic of the battery.

Claims

1. A method for distinguishing between batteries having different chemistry compositions, comprising:

supplying electrical energy to the battery for charging thereof;

monitoring a voltage characteristic of the battery periodically during charging, wherein the voltage characteristic varies over time with the state of charge of the battery;

identifying the chemistry composition of the battery based on the voltage characteristic of the battery.

2. The method of claim 1 determining a slope of the variation in the voltage characteristic and identifying the chemistry composition of the battery based on the slope.

3. The method of claim 2 further comprises identifying the chemistry composition as a lithium based chemistry when the slope exceeds a threshold.

4. The method of claim 2 further comprises discontinue supplying electrical energy to the battery when the slope exceeds a threshold.

5. The method of claim 2 wherein identifying the chemistry composition further comprises identifying a first inflection point exhibited in the voltage characteristic of the battery and identifying the chemistry composition as a lithium based chemistry when a second inflection point is not detected within a defined period of time following the first inflection point.

6. The method of claim 5 further comprises identifying the chemistry composition as a nickel based chemistry when the second inflection point is detected with the defined period of time following the first inflection point.

7. The method of claim 1 further comprises controlling the supply of electrical energy to the battery based on the chemistry composition of the battery.

8. The method of claim 1 further comprises terminating the supply of electrical energy to the battery based on the chemistry composition of the battery.

9. The method of claim 2 wherein identifying the chemistry composition further comprises identifying a first inflection point exhibited in the voltage characteristic of the battery and identifying the chemistry composition as a lithium based chemistry when a second inflection point is not detected within a defined period of time following the first inflection point and the slope exceeds a threshold.

10. A method for distinguishing between batteries having different chemistry compositions, comprising:

supplying electrical energy to the battery for charging thereof;

monitoring a voltage characteristic of the battery periodically during charging, wherein the voltage characteristic varies over time with the state of charge of the battery;

determining a slope of the variation in the voltage characteristic; and

identifying the chemistry composition of the battery based on the slope of the voltage characteristic of the battery.

11. The method of claim 10 further comprises identifying the chemistry composition as a lithium based chemistry when the slope exceeds a threshold.

12. The method of claim 10 further comprises discontinue supplying electrical energy to the battery when the slope exceeds a threshold.

13. The method of claim 10 wherein identifying the chemistry composition further comprises identifying a first inflection point exhibited in the voltage characteristic of the battery and identifying the chemistry composition as a lithium based chemistry when a second inflection point is not detected within a defined period of time following the first inflection point.

14. The method of claim 13 further comprises identifying the chemistry composition as a nickel based chemistry when the second inflection point is detected with the defined period of time following the first inflection point.

15. The method of claim 10 further comprises controlling the supply of electrical energy to the battery based on the chemistry composition of the battery.

16. The method of claim 10 further comprises terminating the supply of electrical energy to the battery based on the chemistry composition of the battery.

17. The method of claim 10 wherein identifying the chemistry composition further comprises identifying a first inflection point exhibited in the voltage characteristic of the battery and identifying the chemistry composition as a lithium based chemistry when a second inflection point is not detected within a defined period of time following the first inflection point and the slope exceeds a threshold.

18. A method for validating a voltage reading circuit for a battery pack operably coupled to a battery charging device, comprising:

reading a voltage across the battery cells in the battery pack;

communicating the voltage reading from the battery pack to the battery charging device;

reading a voltage of the battery pack at terminals which couple the battery pack to the battery charging device;

comparing the voltage across the battery cells to the voltage at the terminals; and

performing a protection operation when a difference between the voltage readings exceeds a range of acceptable values.

19. The method of claim 18 wherein performing a protection operation further comprises terminating charging of the battery cells.