Testing individual cells within multi-cell battery applications

• US 9,557,387 B2
• Filed: 02/10/2015
• Issued: 01/31/2017
• Est. Priority Date: 02/10/2015
• Status: Active Grant

• Current Assignee: Lenovo Enterprise Solutions (Singapore) Pte., Ltd. (Lenovo Group Ltd.)
• Original Assignee: Lenovo Enterprise Solutions (Singapore) Pte., Ltd. (Lenovo Group Ltd.)
• Inventors: Bulur, Yakup, Fishbune, Richard J., Maresh, Mark E., Wheeler, Adam M.
• Primary Examiner(s): FRASER, STEWART A
• Application Number:
  US14/618,100
• Publication Number:
  US 20160231385A1
• Time in Patent Office: 721 Days
• US Class Current: 1/1
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: G01R 31/3842 combining voltage and current measurements
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Embodiments of the invention relate to a multi-cell battery, and individual evaluation of the battery cells. Each cell is individually removed or disconnected from the battery. An adjustable cell charger and an adjustable cell load are mapped to the disconnected cell. As the charger charges the cell, an associated sensor validates acceptance of the charge. As the cell load discharges the cell, the sensor measures discharge characteristics. Operating efficiency of the selected cell is evaluated based on the measured charge acceptance and discharge characteristics.

Claims

1. A method comprising:

selecting a first cell from a plurality of interconnected cells constituting a multi-cell battery;

selecting a spare cell supporting the functionality of the selected first cell;

performing a cell swap, while the multi-cell battery remains in an operating state including;

placing the selected first cell in an offline state;

placing the spare cell in an online state; and

performing an evaluation of the selected first cell.

2. The method of claim 1, wherein performing an evaluation of the selected first cell comprises:

charging the selected first cell to a predetermined cell level and validating acceptance of a charge;

utilizing a discharge parameter, discharging the selected first cell and measuring a discharge characteristic during discharge;

determining operating efficiency of the selected first cell with the validated charge acceptance and the discharge characteristic; and

recharging the first cell utilizing a known recharge parameter and measuring a recharge characteristic of the first cell.

3. The method of claim 2, further comprising storing the measured recharge and discharge characteristics with a controller in communication with the battery.

4. The method of claim 2, wherein the determining operating efficiency of the selected first cell includes measuring temperature of the first cell in the offline state during the discharging and recharging.

5. The method of claim 2, further comprising obtaining capacity of the selected first cell in the offline state during the discharging and recharging of the first cell.

6. The method of claim 2, wherein recharging utilizes a parameter selected from the group consisting of:

voltage and current, at a different level than the charging.

7. The method of claim 1, wherein performing an evaluation of the selected cell utilizes power from at least one unselected cell from the plurality of interconnected cells constituting the multi-cell battery.

8. A computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a controller in communication with a multi-cell battery, the instructions to perform a method comprising:

in the multi-cell battery having a plurality of interconnected cells, individually selecting one of the cells, placing the selected cell in an offline state and placing a spare cell supporting the functionality of the first cell in an online state while the battery remains in an operating state; and

performing an evaluation of the selected cell.

9. The computer program product of claim 8, wherein the performing an evaluation of the selected cell comprises:

charging the selected cell to a predetermined cell level and validating acceptance of a charge;

discharging the selected cell utilizing a known recharge parameter and measuring a discharge characteristic during the discharging;

determining operating efficiency of the selected cell with the validated charge acceptance and the measured discharge characteristic; and

recharging the cell utilizing a known recharge parameter and measuring a recharge characteristic of the cell.

10. The computer program product of claim 9, further comprising storing the measured recharge and discharge characteristics with the controller.

11. The computer program product of claim 9, wherein determining operating efficiency of the selected cell includes measuring temperature of the cell in the offline state during the discharging and recharging.

12. The computer program product of claim 9, further comprising obtaining capacity of the selected cell in the offline state during the discharging and recharging of the cell.

13. The computer program product of claim 9, wherein recharging utilizes a parameter selected from the group consisting of:

voltage and current, at a different level than the charging.

14. A system comprising:

a battery pack arrangement with multiple cells, the cells arranged in a matrix and electrically connected;

a controller in communication with the cells, the controller to select one of the cells in the arrangement, a multiplexer to place the selected cell in an offline state, and place a spare cell supporting the functionality of the first cell in an operating state while the battery pack remains in an operating state; and

the controller to perform an evaluation of the selected cell.

15. The system of claim 14, wherein the controller to perform an evaluation of the selected cell comprises:

a cell charger to charge the selected cell to a predetermined cell level and a sensor to validate acceptance of the charge;

a cell load to discharge the cell utilizing a discharge parameter and the sensor to measure a discharge characteristic during the discharge;

the controller to determine operating efficiency of the selected cell with the validated charge acceptance and the measured discharge characteristic; and

recharge the cell utilizing a recharge parameter and measure a recharge characteristic of the cell.

16. The system of claim 15, further comprising the controller to store the measured recharge and discharge characteristics.

17. The system of claim 15, wherein the controller determination of operating efficiency of the selected cell further comprising, a temperature sensor in communication with the controller, the sensor to measure temperature of the cell in the offline state during cell discharge and recharge.

18. The system of claim 15, further comprising the cell charger to obtain capacity of the selected cell in the offline state during the discharge and recharge of the cell.

19. The system of claim 15, wherein the cell load recharges the selected cell utilizing a parameter selected from the group consisting of:

voltage and current, at a different level than during a charge.

20. The system of claim 14, wherein the sensor to validate acceptance of the charge and to measure a discharge characteristic during the discharge is a current sensor.