Method and system for battery protection

• US 10,224,566 B2
• Filed: 11/13/2017
• Issued: 03/05/2019
• Est. Priority Date: 11/22/2002
• Status: Expired due to Term

• Current Assignee: Milwaukee Electric Tool Corporation (Techtronic Industries Company Limited)
• Original Assignee: Milwaukee Electric Tool Corporation (Techtronic Industries Company Limited)
• Inventors: Johnson, Todd W., Rosenbecker, Jay J., Meyer, Gary D., Zeiler, Jeffrey M., Glasgow, Kevin L., Zick, Jonathan A., Brozek, Jeffrey M., Scheucher, Karl F.
• Primary Examiner(s): Pacheco, Alexis
• Application Number:
  US15/811,616
• Publication Number:
  US 20180131036A1
• Time in Patent Office: 477 Days
• Field of Search: 320119, 320125, 320124, 320128, 320116, 320132, 320121, 320122, 320113, 320114, 320115, 320134, 320145, 324427, 324428, 324431, 324433, 324426, 324429, 324434, 324435, 324436
• CPC Class Codes: B25F 5/00 Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for
• CPC Class Codes: B25F 5/008 Cooling means
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• 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 10/4257 Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• 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 2010/4278 Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
• CPC Class Codes: H01M 2200/00 Safety devices for primary or secondary batteries
• CPC Class Codes: H01M 2220/30 Batteries in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H01M 4/505 of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
• CPC Class Codes: H01M 50/204 Racks, modules or packs for multiple batteries or multiple cells
• CPC Class Codes: H01M 50/213 adapted for cells having curved cross-section, e.g. round or elliptic H01M50/209, H01M50/216 take precedence
• CPC Class Codes: H01M 50/227 Organic material
• CPC Class Codes: H01M 50/247 specially adapted for portable devices, e.g. mobile phones, computers, hand tools or pacemakers
• CPC Class Codes: H01M 50/296 characterised by terminals of battery packs terminals of batteries H01M50/543
• CPC Class Codes: H02J 7/00 : Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0014 : Circuits for equalisation of charge between batteries
• CPC Class Codes: H02J 7/0016 : using shunting, discharge or bypass circuits
• CPC Class Codes: H02J 7/00302 : Overcharge protection
• CPC Class Codes: H02J 7/00306 : Overdischarge protection
• CPC Class Codes: H02J 7/00308 : Overvoltage protection
• CPC Class Codes: H02J 7/00309 : Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0031 : using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0034 : using reverse polarity correcting or protecting circuits mechanical means of polarity protection H02J7/0045
• CPC Class Codes: H02J 7/0045 : concerning the insertion or the connection of the batteries
• CPC Class Codes: H02J 7/0063 : with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/0071 : with a programmable schedule
• CPC Class Codes: H02J 7/04 : Regulation of charging current or voltage
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries

Abstract

An electrical combination. The combination comprises a hand held power tool, a battery pack and a controller. The battery pack includes a battery pack housing connectable to and supportable by the hand held power tool, a plurality of battery cells supported by the battery pack housing, each of the plurality of battery cells having a lithium-based chemistry, being individually tapped and having an individual state of charge. A communication path is provided by a battery pack sense terminal and a power tool sense terminal. The controller is operable to monitor a state of charge of a number of battery cells less than the plurality of battery cells and to generate a signal based on the monitored state of charge of the number of battery cells less than the plurality of battery cells, the signal being operable to control the operation of the hand held power tool.

Claims

1. An electrical combination comprising:

a battery pack configured to supply power to a cordless power tool having a motor, the battery pack including a plurality of battery cells operable to supply a battery pack discharge current to the motor of the cordless power tool, each of the battery cells being individually tapped and having a battery cell state of charge;

a switch operable to be alternately positioned in one of a conducting state and a non-conducting state, the switch further operable to enable the supply of discharge current from the battery pack to the motor when the switch is positioned in the conducting state and operable to interrupt the supply of discharge current from the battery pack to the motor when the switch is positioned in the non-conducting state; and

a controller electrically connected to the switch, operable to monitor the respective battery cell state of charge of each of the battery cells, operable to control operation of the battery pack, and operable to control the positioning of the switch, the controller including a microcontroller;

wherein the controller modifies operation of the battery pack by causing the switch to move from the conducting state to the non-conducting state to interrupt the supply of discharge current from the battery pack to the motor when the monitored respective battery cell state of charge of one of the battery cells reaches a predetermined threshold.

2. The electrical combination as set forth in claim 1 wherein the controller modifies operation of the battery pack by varying the discharge current being supplied to the motor of the cordless power tool over a time period.

3. The electrical combination as set forth in claim 1 wherein the controller modifies operation of the battery pack by decreasing the discharge current being supplied to the motor of the cordless power tool over a time period.

4. The electrical combination as set forth in claim 1 wherein the controller modifies operation of the battery pack by interrupting the discharge current being supplied to the motor of the cordless power tool such that substantially no discharge current is supplied to the motor of the cordless power tool for a time period.

5. The electrical combination as set forth in claim 1 wherein the controller further modifies operation of the battery pack when the monitored respective battery cell state of charge of one of the battery cells reaches a second predetermined threshold, the second predetermined threshold being different than the predetermined threshold.

6. The electrical combination as set forth in claim 5 wherein the second predetermined threshold is greater than the predetermined threshold.

7. The electrical combination as set forth in claim 5 wherein the controller further modifies operation of the battery pack by causing the switch to move from the non-conducting state to the conducting state to conduct the discharge current when the monitored respective battery cell state of charge of one of the battery cells reaches the second predetermined threshold.

8. The electrical combination as set forth in claim 1 wherein each of the battery cells has a battery cell chemistry that is Lithium-based.

9. The electrical combination as set forth in claim 1 wherein the controller is located within a housing of the battery pack.

10. The electrical combination as set forth in claim 1 wherein the switch is located within a housing of the battery pack.

11. A method of operating an electrical combination, the electrical combination including a battery pack configured to supply power to a cordless power tool having a motor, the method comprising:

monitoring, with a controller, a respective battery cell state of charge of a plurality of battery cells included in the battery pack, the plurality of battery cells operable to supply a battery pack discharge current to the motor of the cordless power tool, each of the battery cells being individually tapped;

controlling, with the controller, a switch to be in a conducting state to enable the supply of discharge current from the battery pack to the motor, the controller being electrically connected to the switch and including a microcontroller; and

modifying operation of the battery pack, with the controller, by causing the switch to move from the conducting state to a non-conducting state to interrupt the supply of discharge current from the battery pack to the motor when the monitored respective battery cell state of charge of one of the battery cells reaches a predetermined threshold.

12. The method as set forth in claim 11 wherein modifying operation of the battery pack includes varying the discharge current being supplied to the motor of the cordless power tool over a time period.

13. The method as set forth in claim 11 wherein modifying operation of the battery pack includes decreasing the discharge current being supplied to the motor of the cordless power tool over a time period.

14. The method as set forth in claim 11 wherein modifying operation of the battery pack includes interrupting the discharge current being supplied to the motor of the cordless power tool such that substantially no discharge current is supplied to the motor of the cordless power tool for a time period.

15. The method as set forth in claim 11 further comprising:

further modifying operation of the battery pack, with the controller, when the monitored respective battery cell state of charge of one of the battery cells reaches a second predetermined threshold, the second predetermined threshold being different than the predetermined threshold.

16. The method as set forth in claim 15 wherein the second predetermined threshold is greater than the predetermined threshold.

17. The method as set forth in claim 15 wherein further modifying operation of the battery pack includes causing the switch to move from the non-conducting state to the conducting state to conduct the discharge current when the monitored respective battery cell state of charge of one of the battery cells reaches the second predetermined threshold.

18. The method as set forth in claim 11 wherein each of the battery cells has a battery cell chemistry that is Lithium-based.

19. The method as set forth in claim 11 wherein the controller is located within a housing of the battery pack.

20. The method as set forth in claim 11 wherein the switch is located within a housing of the battery pack.