Diffusion-limited adaptive battery charging

• US 10,044,210 B2
• Filed: 06/22/2015
• Issued: 08/07/2018
• Est. Priority Date: 04/11/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Greening, Thomas C., Ungar, P. Jeffrey, Athas, William C.
• Primary Examiner(s): Pacheco, Alexis
• Application Number:
  US14/746,665
• Publication Number:
  US 20160087461A1
• Time in Patent Office: 1,142 Days
• Field of Search: 320107, 320105, 320108, 320109, 320134, 320135, 320132, 320148, 320160, 320162, 320129, 320141, 320145, 320151, 320163, 320118, 320122, 320128, 320137
• CPC Class Codes: G01P 15/00 Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
• CPC Class Codes: G01P 3/56 for comparing two speeds
• 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 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/443 in response to temperature
• 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: H01M 2300/00 Electrolytes
• CPC Class Codes: H01M 50/00 Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0042 characterised by the mechanical construction
• CPC Class Codes: H02J 7/007 Regulation of charging or discharging current or voltage
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

Some embodiments of the present invention provide a system that adaptively charges a battery, wherein the battery is a lithium-ion battery which includes a transport-limiting electrode governed by diffusion, an electrolyte separator and a non-transport-limiting electrode. During operation, the system determines a lithium surface concentration at an interface between the transport-limiting electrode and the electrolyte separator based on a diffusion time for lithium in the transport-limiting electrode. Next, the system calculates a charging current or a charging voltage for the battery based on the determined lithium surface concentration. Finally, the system applies the charging current or the charging voltage to the battery.

Claims

1. A battery charger comprising:

a controller;

a plurality of sensors coupled to the controller, and each coupleable to a battery having a first electrode, a second electrode, and at least one interface therebetween; and

at least one of a current source and a voltage source, each coupled to the controller and coupleable to the battery,

wherein the controller is configured to;

during a zero current state in which charging current of the battery is set to zero following a prior charging period, receive from the plurality of sensors,. information corresponding to the prior charging period; and

subsequent to the zero current state and based at least in part on the received information, control at least one of the current source and the voltage source to charge the battery;

wherein the plurality of sensors comprise a voltage sensor and a current sensor and the received information comprises voltage information and current information.

2. The battery charger of claim 1, wherein the controller is further configured to:

determine a concentration of lithium at the at least one interface based at least in part on the received information, wherein the controller is configured to determine the concentration of lithium at the at least one interface by determining a potential of at least one of the first electrode and the second electrode with respect to a predetermined reference; and

based further at least in part on the determined concentration of lithium at the at least one interface, control at least one of the current source and the voltage source to charge the battery.

3. The battery charger of claim 1, wherein the plurality of sensors further comprise a temperature sensor and the received information further comprises temperature information.

4. The battery charger of claim 3, wherein the controller is further configured to:

determine a concentration of lithium at the at least one interface based at least in part on the received information, by determining a potential of at least one of the first electrode and the second electrode with respect to a predetermined reference; and

based further at least in part on the determined concentration of lithium at the at least one interface, control at least one of the current source and the voltage source to charge the battery.

5. The battery charger of claim 3, wherein the plurality of sensors further comprise a state of charge estimator and the received information further comprises state of charge information.

6. The battery charger of claim 5, wherein the controller is further configured to:

determine a concentration of lithium at the at least one interface, further based at least in part on the received information, by determining a potential of at least one of the first electrode and the second electrode with respect to a predetermined reference; and

based further at least in part on the determined concentration of lithium at the at least one interface control at least one of the current source and the voltage source to charge the battery.

7. The battery charger of claim 5, wherein the voltage sensor is a voltmeter, the current sensor is a current meter, and the temperature sensor is a thermal sensor.

8. A controller for a battery charger including a current source and a voltage source, the controller configured to:

during a zero current state in which charging current of a battery is set to zero following a prior charging period, receive information from a plurality of sensors corresponding to the prior charging period; and

subsequent to the zero current state and based at least in part on the received information, control at least one of the current source and the voltage source to charge the battery;

wherein the plurality of sensors comprises a voltage sensor and a current sensor and the received information comprises voltage information and current information.

9. The controller of claim 8, the controller further configured to:

determine a concentration of lithium at an interface between two electrodes of the battery based at least in part on the received information, wherein the controller is configured to determine the concentration of lithium at the interface by determining a potential of at least one of the electrodes with respect to a predetermined reference; and

based further at least in part on the determined lithium concentration at the interface, control at least one of the current source and the voltage source to charge the battery.

10. The controller of claim 8, wherein the plurality of sensors further comprises a temperature sensor and the received information further comprises temperature information.

11. The controller of claim 10, the controller further configured to:

determine a concentration of lithium at an interface between two electrodes of the battery based at least in part on the received information, by determining a potential of at least one of the electrodes with respect to a predetermined reference; and

based further at least in part on the determined concentration of lithium at the interface, control at least one of the current source and the voltage source to charge the battery.

12. The controller of claim 10, wherein the voltage sensor is a voltmeter, the current sensor is a current meter, and the temperature sensor is a thermal sensor.

13. The controller of claim 10, wherein the plurality of sensors further comprises a state of charge estimator and the received information further comprises state of charge information.

14. The controller of claim 12, the controller further configured to:

determine a concentration of lithium at an interface between two electrodes of the battery based at least in part on the received information, by determining a potential of at least one of the electrodes with respect to a predetermined reference; and

based further at least in part on the determined concentration of lithium at the interface, control at least one of the current source and the voltage source to charge the battery.

15. A non-transitory computer readable storage medium storing instructions which, when executed by a controller, cause the controller to:

during a zero current state in which charging current of a battery is set to zero following a prior charging period, receive information from a plurality of sensors corresponding to the prior charging period; and

subsequent to the zero current state and based at least in part on the received information, control at least one of a current source and a voltage source to charge the battery;

wherein the plurality of sensors comprises a voltage sensor and a current sensor and the received information comprises voltage information and current information.

16. The non-transitory computer readable storage medium of claim 15, further storing instructions which, when executed by the controller, cause the controller to:

determine a concentration of lithium at an interface between two electrodes of the battery based at least in part on the received information, by determining a potential of at least one of the electrodes with respect to a predetermined reference; and

based further at least in part on the determined lithium concentration, control at least one of a current source and a voltage source to charge the battery.

17. The non-transitory computer readable storage medium of claim 15, wherein the plurality of sensors further comprises a temperature sensor and the received information further comprises temperature information.

18. The non-transitory computer readable storage medium of claim 17, further storing instructions which, when executed by the controller, cause the controller to:

determine a concentration of lithium at an interface between two electrodes of the battery based at least in part on the received information, by determining a potential of at least one of the electrodes with respect to a predetermined reference; and

based further at least in part on the determined concentration of lithium at the interface, control at least one of a current source and a voltage source to charge the battery.

19. The non-transitory computer readable storage medium of claim 17, wherein the voltage sensor is a voltmeter, the current sensor is a current meter, and the temperature sensor is a thermal sensor.

20. The non-transitory computer readable storage medium of claim 17, wherein the plurality of sensors further comprises a state of charge estimator and the received information further comprises state of charge information.

21. The non-transitory computer readable storage medium of claim 20, further storing instructions which, when executed by the controller, cause the controller to:

determine a concentration of lithium at an interface between two electrodes of the battery based at least in part on the received information, by determining a potential of at least one of the electrodes with respect to a predetermined reference; and

based further at least in part on the determined concentration of lithium at the interface, control at least one of a current source and a voltage source to charge the battery.