SYSTEM AND METHOD FOR RE-INITIATING CHARGE CYCLE FOR BATTERY PACK LEFT IN A CHARGER

• US 20090058368A1
• Filed: 08/21/2008
• Published: 03/05/2009
• Est. Priority Date: 09/05/2007
• Status: Active Grant

• Current Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Inventors: White, Daniel J., Seman, Andrew E. JR.
• Granted Patent: US 8,358,108 B2
• Time in Patent Office: Days
• US Class Current: 320/137
• CPC Class Codes: H01M 10/4257 Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 50/202 Casings or frames around the primary casing of a single cell or a single battery
• CPC Class Codes: H01M 50/204 Racks, modules or packs for multiple batteries or multiple cells
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0069 Charging or discharging for charge maintenance, battery initiation or rejuvenation
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A system and method is provided for initiating a charge cycle for a battery pack left in a battery charger. The battery pack includes a battery control unit which is operable to place the battery pack in a sleep mode after a predefined period of inactivity. The battery charger in turn is operable to deliver a charging signal to the battery pack in response to the battery pack entering a sleep mode.

Claims

1. A charging system for a battery pack, comprising

a battery pack having one or more battery cells and a battery control unit therein, the battery control unit operable to place the battery pack in a sleep mode after a predefined period of inactivity;

and

a battery charger adapted to receive the battery pack and operable to deliver a charging signal to the battery pack in response to the battery pack entering a sleep mode.

2. The charging system of claim 1 wherein the battery pack having two charging terminals such that the battery control unit removes a voltage present at the charging terminal when the battery pack enters a sleep mode.

3. The charging system of claim 1 wherein the battery pack having a switch in series with the battery cells such that the battery control unit opens the switch upon entering a sleep mode.

4. The charging system of claim 1 wherein the battery charger having a charge control unit which maintains an indicator for when to charge the battery pack, wherein the charge control unit sets the indicator to charge the battery pack when the battery pack enters a sleep mode.

5. The charging system of claim 4 wherein the battery charger sends a signal to awaken the battery pack when the battery pack enters a sleep mode.

6. The charging system of claim 5 wherein the battery charger delays sending the signal to awaken the battery pack until expiration of a timer maintained in the battery charger.

7. The charging system of claim 5 wherein the battery pack having a switch in series with the battery cells such that the battery control unit opens the switch upon entering a sleep mode and closes the switch when awoken from a sleep mode.

8. The charging system of claim 5 wherein the charge control unit is operable to deliver a charging signal to the battery pack when the indicator is set to charge the battery pack and the charge control unit detects the battery pack operably coupled to the battery charger.

9. A charging system for a battery pack, comprising:

a battery pack having one or more battery cells and a battery control unit therein, the battery control unit operable to reduce discharge rate of the battery cells from a normal discharge rate when the battery pack has been inactive for a period of time; and

a battery charger adapted to receive the battery pack, the battery charger operable to maintain an indicator as to whether to charge the battery pack and to set the indicator when a battery pack operably coupled thereto reduces its discharge rate from the normal discharge rate.

10. The charging system of claim 9 wherein the battery pack having two charging terminals such that the battery control unit removes a voltage present at the charging terminal to reduce the discharge rate.

11. The charging system of claim 9 wherein the battery pack having a switch in series with the battery cells such that the battery control unit opens the switch to reduce the discharge rate.

12. The charging system of claim 9 wherein the battery charger sends a ready-to-charge signal to battery pack and the battery pack resumes a normal discharge rate in response to the signal.

13. The charging system of claim 9 wherein the battery control unit initiates a timer when the battery pack has been inactive for the period of time and resumes the normal discharge rate when the timer expires.

14. The charging system of claim 9 wherein the battery charger sets the indicator to a fully charged state when the battery pack has been charged.

15. The charging system of claim 9 wherein the battery charger is operable to deliver a charging signal to the battery pack when the battery pack operably coupled thereto resumes a normal discharge rate.

16. A method for initiating a charge cycle for a battery pack operably coupled to a battery charger, comprising:

placing a battery pack into a sleep mode when the battery pack has been inactive for a period of time, wherein the battery pack is operable to reduce discharge of battery cells residing therein during the sleep mode;

awakening the battery pack from the sleep mode; and

delivering a charging signal to the battery pack when the battery pack is awoken from the sleep mode and is operably coupled to a battery charger.

17. The method of claim 16 further comprises sending a read-to-charge signal to the battery pack from the battery charger to awaken the battery pack.

18. The method of claim 16 further comprises initiating a timer upon entering the sleep mode and awakening the battery pack from the sleep mode when the timer expires.

19. The method of claim 16 further comprises maintaining an indicator for when to charge the battery pack and setting the indicator to charge the battery pack when the battery pack enters a sleep mode.

20. The method of claim 16 further comprises setting the indicator to a fully charged state after a battery pack has been charged.

21. The method of claim 19 further comprises maintaining the indicator in the battery charger.

22. The method of claim 18 further comprises maintaining the indicator in the battery pack.