Power source having a parallel cell topology

• US 8,143,851 B2
• Filed: 02/15/2008
• Issued: 03/27/2012
• Est. Priority Date: 02/15/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Athas, William, Michalske, Steven Charles, Greening, Thomas Charles
• Primary Examiner(s): DIAO, M BAYE
• Application Number:
  US12/032,513
• Publication Number:
  US 20090208824A1
• Time in Patent Office: 1,502 Days
• Field of Search: 320/116, 320/117, 320/121
• US Class Current: 320/116
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/12 Recording operating variables ; Monitoring of operating variables
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: G06F 1/189 Power distribution
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H02J 1/102 being switching converters H02J1/108, H02J1/12 take precedence
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02M 3/1582 Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

A power source with multiple cells connected in parallel to a common node or power supply point. The individual cells within the power source may also have a dedicated controller for each of the individual cells such that the dedicated controllers are connected on a one to one basis with each of the respective individual cells.

Claims

1. A power source comprising:

at least two individual cells, each of the at least two individual cells configured only in parallel with all other individual cells;

at least two controllers, wherein each of the at least two individual controllers is operationally connected on a one to one basis to each of the at least two individual cells;

a common node wherein each of the at least two individual controllers and each of the at least two individual cells is operationally connected to the common node, and

a system controller coupled to the at least two controllers and configured to;

determine a charge capacity of each individual cell; and

allocate power discharge from the at least two individual cells based on the charge capacity of each individual cell.

2. The power source of claim 1 wherein:

each of the at least two controllers is a buck-boost controller; and

each buck-boost controller is operationally connected to a power bus and operationally connected to each corresponding cell of the at least two individual cells.

3. The power source of claim 1, wherein a feedback loop including the system controller connects the cell with the highest remaining capacity of the at least two individual cells directly to the power bus.

4. The power source of claim 1 wherein:

a feedback loop, including the system controller, connects each cell of the at least two cells to a power bus, further wherein;

each cell of the at least two individual cells does not have full capacity remaining; and

power is discharged from each cell corresponding to a respective fraction of a total remaining capacity of each cell of the at least two individual cells.

5. The power source of claim 1 wherein each of the at least two individual cells is sequentially isolated.

6. The power source of claim 5 further wherein the sequential isolation of each cell of the at least two individual cells automates a calibration of state of charge measurements.

7. The power source of claim 1 wherein the cell with the least amount of charge is isolated.

8. The power source of claim 1 further comprising replacing the at least one cell with the compromised capacity.

9. The power source of claim 1 wherein at least one of the cells of the at least two individual cells used in the power source has a different cell capacity.

10. The power source of claim 1 wherein:

a plurality of cells are distributed in a system; and

at least one of the cells of the plurality of cells is located non-adjacently in the system.

11. The power source of claim 1 wherein at least one of the cells of the at least two individual cells used in a system has a different cell capacity than the other cells.

12. A method for isolating cells in a power source, comprising:

configuring at least two individual cells in parallel, wherein each individual cell is configured only in parallel with every individual cell;

dedicating each controller of at least two controllers to each cell of the at least two individual cells such that each controller has a one to one correspondence with each individual cell and is operationally connected to each individual cell;

connecting each individual controller and each individual cell to a common node; and

communicatively coupling a system controller to each of the at least two controllers, wherein the system controller is configured to;

determine a relative charge capacity of each individual cell; and

direct each individual controller to regulate power discharged from its corresponding individual cell based on signals received from the system controller corresponding to the cells relative charge capacity.

13. The method of claim 12, wherein:

each controller of the at least two controllers is a buck-boost controller; and

each buck-boost controller of the at least two controllers is configured between a power bus and each corresponding cell of the at least two individual cells.

14. The method of claim 12, further comprising connecting the cell with the highest remaining capacity of the plurality of cells directly to the power bus using a feedback loop.

15. The method of claim 12, further comprising:

connecting each cell of the at least two individual cells to the power bus using a feedback loop, wherein;

when each cell of the at least two individual cells is at less than full capacity, discharging power from each of the at least two individual cells in a ratio corresponding to a respective fraction of a total remaining capacity of each cell.

16. The method of claim 12, further comprising sequentially isolating each cell of the at least two individual cells.

17. The method of claim 16 wherein the sequential isolation of each cell of the at least two individual cells automates a calibration of state of charge measurements.

18. The method of claim 12, further comprising isolating the cell with the least amount of charge of the at least two individual cells.

19. The method of claim 16, further comprising replacing at least one cell of the at least two individual cells, the one cell having a compromised capacity.

20. The method of claim 12 wherein at least one of the cells of the at least two individual cells used in a system has a different cell capacity than the other cells.

21. The method of claim 12 further comprising:

distributing a plurality of cells in a system; and

locating at least one of the cells in the plurality of cells non-adjacently in the system.