Method and apparatus for extending lifetime for rechargeable stationary energy storage devices

• US 8,773,066 B2
• Filed: 08/18/2010
• Issued: 07/08/2014
• Est. Priority Date: 08/18/2010
• Status: Active Grant

• Current Assignee: Tesla Inc.
• Original Assignee: Tesla Motors Incorporated (Tesla Inc.)
• Inventors: Kelty, Kurt Russell
• Primary Examiner(s): Dunn, Drew A
• Assistant Examiner(s): GRANT, ROBERT J
• Application Number:
  US12/859,254
• Publication Number:
  US 20120046795A1
• Time in Patent Office: 1,420 Days
• Field of Search: 320/109
• US Class Current: 320/109
• 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 a vehicle battery pack, the method comprising the steps of:

implementing a vehicle battery pack for a plug-in vehicle as a community energy storage connected to a utility grid;

defining an active energy consumption season for the vehicle battery pack based at least on seasonal temperature information;

performing a season exception determination based at least on a short-term weather prediction;

operating the vehicle battery pack in a usage mode (i) during said active energy consumption season except when the season exception determination indicates otherwise, and also (ii) outside of the active energy consumption season as indicated by the season exception determination, wherein said usage mode includes charging the vehicle battery pack to a full state-of-charge (SOC) in each charging session; and

operating the vehicle battery pack in a lifetime-extending storage mode (i) outside of the active energy consumption season except when the season exception determination indicates otherwise, and also (ii) during the active energy consumption season as indicated by the season exception determination, wherein said storage mode includes charging the vehicle battery pack to a lifetime prolonging SOC less than the full SOC in each charging session.

2. The computer-implemented method of claim 1 wherein said defining step includes estimating said active energy consumption season 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 vehicle battery pack, a forecast for the environmental temperature, an energy consumption trend for the vehicle battery pack, a period indicator signal provided to the vehicle battery pack from an external process, a period indicator signal provided to the vehicle battery pack 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 3 wherein the vehicle battery pack 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.

5. The computer-implemented method of claim 1 wherein said active season corresponds to a local community-wide sustained elevated energy consumption pattern.

6. The computer-implemented method of claim 1 wherein the vehicle battery pack 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.

7. The computer-implemented method of claim 6 wherein said predetermined level for said internal temperature is about 30°

C. or greater.

8. The computer-implemented method of claim 7 wherein said reduced SOC for said active mode in a range of about 20% to about 80% of said full SOC.

9. An energy management system for a vehicle battery pack, comprising:

a vehicle battery pack for a plug-in vehicle implemented as a community energy storage connected to a utility grid;

a charging system coupled to the vehicle battery pack;

a collection system for gathering a set of operational parameters for the vehicle battery pack, said set of operational parameters including data permitting determination of an active season for the energy storage device, the data including seasonal temperature information and a short-term weather prediction; and

a controller, coupled to said charging system and to said collection system, to (A) determine, responsive to said set of operational parameters, the active season for operation of the vehicle battery pack, and (B) perform a season exception determination based at least on the short-term weather prediction, said controller operating the vehicle battery pack in a usage mode (i) during the active season except when the season exception determination indicates otherwise, and also (ii) outside of the active season as indicated by the season exception determination, the usage mode comprising controlling said charging system to charge the vehicle battery pack to a full state-of-charge (SOC) in each charging session, and said controller operating the vehicle battery pack in a lifetime-extending storage mode (i) outside of the active season except when the season exception determination indicates otherwise, and also (ii) during the active season as indicated by the season exception determination, the lifetime-extending storage mode comprising controlling said charging system to charge the vehicle battery pack to a lifetime-prolonging SOC less than the full SOC in each charging session.

10. The energy management system of claim 9 wherein said one or more operating parameters include one or more of an environmental temperature of a volume surrounding the vehicle battery pack, a forecast for the environmental temperature, an energy consumption trend for the vehicle battery pack, a period indicator signal provided to the vehicle battery pack from an external process, a period indicator signal provided to the vehicle battery pack 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.

11. The energy management system of claim 9 wherein the vehicle battery pack 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.

12. The energy management system of claim 9 wherein said active season corresponds to a community-wide sustained elevated energy consumption pattern.

13. The energy management system of claim 9 wherein the vehicle battery pack includes a housing and wherein an internal temperature of said housing is measured, and wherein an SOC target for both said modes is reduced when said internal temperature exceeds a predetermined level.

14. The energy management system of claim 13 wherein said predetermined level for said internal temperature includes a temperature of at least 30°

C.

15. The energy management system of claim 14 wherein said lifetime-prolonging SOC is in a range of about 20% to about 80% of said full SOC.