Electric vehicle battery lifetime optimization operational mode

• US 8,907,629 B2
• Filed: 02/28/2012
• Issued: 12/09/2014
• Est. Priority Date: 02/28/2012
• Status: Active Grant

• Current Assignee: Tesla Inc.
• Original Assignee: Tesla Motors Incorporated (Tesla Inc.)
• Inventors: Kelty, Kurt Russell, Hermann, Weston Arthur, Kohn, Scott Ira, Kishiyama, Clay Hajime, Mehta, Vineet Haresh, Stewart, Sarah G.
• Primary Examiner(s): TSO, EDWARD H
• Application Number:
  US13/406,773
• Publication Number:
  US 20130221916A1
• Time in Patent Office: 1,015 Days
• Field of Search: 320/109, 320/132, 320/149, 320/150
• US Class Current: 320/132
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• 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: B60L 58/24 for controlling the temperature of batteries
• 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: H02J 7/007194 of the battery
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A multi-mode operating system for an electric vehicle is provided, the system including means for a user to select a preferred mode of operation from a plurality of operational modes that include at least a Battery Life mode and a Standard mode, wherein the Battery Life mode is configured to select operating and charging parameters that emphasize battery health and battery life over vehicle range and/or vehicle performance. The system includes a thermal management system for maintaining the vehicle'"'"'s battery pack to within any of a plurality of temperature ranges, and a charging system for charging the vehicle'"'"'s battery pack to any of a plurality of minimum and maximum SOC levels and at any of a plurality of charging rates.

Claims

1. A multi-mode operating system for an electric vehicle, comprising:

a battery charging system for charging a battery pack of said electric vehicle, wherein said battery charging system charges said battery pack to any of a plurality of maximum and minimum state-of-charge (SOC) levels, and wherein said battery charging system charges said battery pack using any of a plurality of charging rates;

a thermal management system coupled to said battery pack of said electric vehicle, wherein said thermal management system maintains said battery pack to within any of a plurality of temperature ranges;

a vehicle control system coupled to said battery charging system and to said thermal management system; and

means for selecting a vehicle operating mode from a plurality of operational modes controlled by said vehicle control system, wherein said plurality of operational modes includes at least a Battery Life mode and a Standard mode, wherein said selecting means is accessible by a user of said electric vehicle, wherein said Battery Life mode utilizes a first maximum SOC level during battery pack charging that is at least 10% lower than a second maximum SOC level utilized in said Standard mode, wherein said Battery Life mode utilizes a first maximum charge rate and said Standard mode utilizes a second maximum charge rate that is higher than said first maximum charge rate, wherein said Battery Life mode utilizes a first maximum discharge rate and said Standard mode utilizes a second maximum discharge rate that is higher than said first maximum discharge rate.

2. The multi-mode operating system of claim 1, wherein said first maximum SOC level is preset at 60% or less, wherein said first maximum charge rate is preset at C/20 or less, and wherein said first maximum discharge rate is preset at 1C or less.

3. The multi-mode operating system of claim 1, wherein said Battery Life mode utilizes a first minimum SOC level during battery pack charging that is at least 5% higher than a second minimum SOC level utilized in said Standard mode.

4. The multi-mode operating system of claim 1, wherein said Battery Life mode utilizes a first minimum SOC level during battery pack charging that is at least 15% higher than a second minimum SOC level utilized in said Standard mode.

5. The multi-mode operating system of claim 1, wherein said Battery Life mode utilizes a minimum loaded voltage set to a preset level of approximately 3.0 volts.

6. The multi-mode operating system of claim 1, wherein said thermal management system maintains said battery pack during discharge to a first temperature within a first range of temperatures when said Battery Life mode is selected, wherein said thermal management system maintains said battery pack during discharge to a second temperature within a second range of temperatures when said Standard mode is selected, and wherein said first range of temperatures is less than said second range of temperatures.

7. The multi-mode operating system of claim 6, wherein said first range of temperatures is approximately 25°

C. to 30°

C., and said second range of temperatures is approximately 30°

C. to 35°

C.

8. The multi-mode operating system of claim 1, further comprising at least one battery pack temperature sensor, wherein said first maximum charge rate utilized when said Battery Life mode is selected depends on a battery pack temperature, wherein said first maximum charge rate is preset at C/20 or less if said battery pack temperature is above 10°

C., and wherein said first maximum discharge rate is preset at C/50 or less if said battery pack temperature is below 10°

C.

9. The multi-mode operating system of claim 1, wherein during discharge said thermal management system maintains a thermal balance between a plurality of cells comprising said battery pack within a first preset limit when said Battery Life mode is selected and within a second preset limit when said Standard mode is selected, and wherein said first preset limit is less than said second preset limit.

10. The multi-mode operating system of claim 9, wherein said first preset limit is approximately 5°

C. and said second preset limit is approximately 10°

C.

11. The multi-mode operating system of claim 1, wherein during an extended charging cycle said battery charging system allows said battery pack to self-discharge to a first minimum SOC level prior to re-initiating charging when said Battery Life mode is selected and to a second minimum SOC level prior to re-initiating charging when said Standard mode is selected, wherein said first minimum SOC level is at least 25% less than said second minimum SOC level.

12. The multi-mode operating system of claim 11, wherein said first minimum SOC level is at least 30% less than said first maximum SOC level.

13. The multi-mode operating system of claim 1, wherein said selecting means is comprised of a touch-sensitive screen.

14. The multi-mode operating system of claim 1, wherein said selecting means is comprised of a display system and a plurality of switching means.

15. The multi-mode operating system of claim 14, wherein said switching means are selected from the group consisting of push-buttons, toggle switches, rotating switches and slide switches.

16. The multi-mode operating system of claim 1, wherein said selecting means is comprised of a plurality of switching means.

17. The multi-mode operating system of claim 1, wherein said selecting means is a voice recognition system.

18. The multi-mode operating system of claim 1, further comprising a communication interface in communication with a network, wherein said selecting means is a remote mode selector in communication with said network, wherein said remote mode selector is separate from said electric vehicle.

19. The multi-mode operating system of claim 1, further comprising an RF communication interface, wherein said selecting means is an RF remote mode selector separate from said electric vehicle.

20. The multi-mode operating system of claim 1, further comprising at least one mode indicator, wherein said at least one mode indicator indicates which mode of said plurality of operational modes is selected by said selecting means.