METHOD AND APPARATUS FOR EXTENDING LIFETIME FOR RECHARGEABLE STATIONARY ENERGY STORAGE DEVICES

• US 20120046795A1
• Filed: 08/18/2010
• Published: 02/23/2012
• Est. Priority Date: 08/18/2010
• Status: Active Grant

• Current Assignee: Tesla Inc.
• Original Assignee: Tesla Motors Incorporated (Tesla Inc.)
• Inventors: Kelty, Kurt R.
• Granted Patent: US 8,773,066 B2
• Time in Patent Office: Days
• US Class Current: 700/291
• CPC Class Codes: B60L 2240/662 Temperature
• CPC Class Codes: B60L 58/16 responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2710/244 Charge state
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/0069 Charging or discharging for charge maintenance, battery initiation or rejuvenation
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A flexible management system and method for efficiently operating energy storage devices to extend the lifetime and decrease costs includes (a) determining an active energy consumption period for the energy storage device; (b) determining an inactive energy consumption period for the energy storage device; (c) operating the energy storage device in a usage mode during the active energy consumption period; and (d) operating the energy storage device in a storage mode during the inactive energy consumption period.

Claims

1. A computer-implemented method for operating an energy storage device, the method comprising the steps of:

(a) determining an active energy consumption period for the energy storage device;

(b) determining an inactive energy consumption period for the energy storage device;

(c) operating the energy storage device in a usage mode during said active energy consumption period; and

(d) operating the energy storage device in a lifetime-extending storage mode during said inactive energy consumption period.

2. The computer-implemented method of claim 1 wherein said determining steps include estimating said active energy consumption period and said inactive energy consumption period from evaluations of one or more operating parameters.

3. The computer-implemented method of claim 2 wherein said one or more operating parameters include one or more of an environmental temperature of a volume surrounding the energy storage device, a forecast for the environmental temperature, an energy consumption trend for the energy storage device, a period indicator signal provided to the energy storage device from an external process, a period indicator signal provided to the energy storage device from an internal process, an atmospheric pressure of the volume, a forecast of the atmospheric pressure of the volume, a weather forecast, and combinations thereof.

4. The computer-implemented method of claim 1 wherein said storage mode includes a lifetime prolonging state-of-charge (SOC) and wherein said usage mode includes a full SOC that is greater than said lifetime prolonging SOC.

5. The computer-implemented method of claim 4 wherein the energy storage device includes rechargeable lithium ion battery cells and wherein said lifetime prolonging SOC is in a range of about 20% to about 80% of said full SOC.

6. The computer-implemented method of claim 1 wherein said active period corresponds to a local community-wide sustained elevated energy consumption pattern and wherein said inactive period corresponds to a local community-wide sustained reduced energy consumption pattern.

7. The computer-implemented method of claim 6 wherein said active period includes a local “

summer”

period and wherein said inactive period includes a local “

non-summer”

period.

8. The computer-implemented method of claim 1 wherein the energy storage device includes a housing containing energy storage elements, wherein an internal temperature of said housing is measured, and wherein a state-of-charge (SOC) target for at least one of said modes is reduced when said internal temperature exceeds a predetermined level.

9. The computer-implemented method of claim 8 wherein said predetermined level for said internal temperature is about 30°

C. or greater.

10. The computer-implemented method of claim 9 wherein said reduced SOC for said active mode in a range of about 20% to about 80% of said full SOC.

11. An energy management system for an energy storage device, comprising:

a charging system coupled to the energy storage device;

a collection system for gathering a set of operational parameters of the energy storage device, said set of operational parameters including data permitting determination of both an active period for the energy storage device and an inactive period for the energy storage device; and

a controller, coupled to said charging system and to said collection system, to determine, responsive to said set of operational parameters, an active period for operation of the energy storage device and an inactive period for operation of the energy storage device, said controller operating said charger to charge the energy storage device to a usage state-of-charge (SOC) when the energy storage device is in said active mode and said controller operating said charger to charge the energy storage device to a storage SOC when the energy storage device is in said inactive mode.

12. The energy management system of claim 11 wherein said controller estimates said active energy consumption period and said inactive energy consumption period from evaluations of one or more operating parameters.

13. The energy management system of claim 12 wherein said one or more operating parameters include one or more of an environmental temperature of a volume surrounding the energy storage device, a forecast for the environmental temperature, an energy consumption trend for the energy storage device, a period indicator signal provided to the energy storage device from an external process, a period indicator signal provided to the energy storage device from an internal process, an atmospheric pressure of the volume, a forecast of the atmospheric pressure of the volume, a weather forecast, and combinations thereof.

14. The energy management system of claim 11 wherein said storage mode includes a storage lifetime prolonging state-of-charge (SOC) and wherein said usage mode includes a full SOC that is greater than said lifetime prolonging SOC.

15. The energy management system of claim 14 wherein the energy storage device includes rechargeable lithium ion battery cells and wherein said lifetime prolonging SOC is in a range of about 20% to about 80% of said full SOC.

16. The energy management system of claim 11 wherein said active period corresponds to a community-wide sustained elevated energy consumption pattern and wherein said inactive period corresponds to a community-wide sustained depressed energy consumption pattern.

17. The energy management system of claim 16 wherein said active period includes a local “

summer”

period and wherein said inactive period includes a local “

non-summer”

period.

18. The energy management system of claim 11 wherein the energy storage device includes a housing and wherein an internal temperature of said housing is measured, and wherein a state-of-charge (SOC) target for both said modes is reduced when said internal temperature exceeds a predetermined level.

19. The energy management system of claim 18 wherein said predetermined level for said internal temperature includes a temperature of at least 30°

C.

20. The energy management system of claim 19 wherein said reduced. SOC for said active mode is in a range of about 20% to about 80% of said full SOC.