Thermal event management system for an electric vehicle

• US 9,954,259 B1
• Filed: 12/07/2016
• Issued: 04/24/2018
• Est. Priority Date: 12/07/2016
• Status: Active Grant

• Current Assignee: Proterra Powered LLC
• Original Assignee: Proterra AG
• Inventors: Grace, Dustin, Pevear, Brian
• Primary Examiner(s): Godo, Olatunji
• Application Number:
  US15/372,000
• Time in Patent Office: 503 Days
• CPC Class Codes: B60L 2200/18 Buses
• CPC Class Codes: B60L 2250/10 by alarm
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: B60L 58/25 by controlling the electric load
• CPC Class Codes: B60L 58/26 by cooling
• CPC Class Codes: B60L 58/27 by heating
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• 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 10/486 for measuring temperature
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/625 Vehicles
• CPC Class Codes: H01M 10/63 Control systems charging or discharging in response to temperature H01M10/44 , H01M10/443; measurement of temperature H01M10/48 , H01M10/486
• CPC Class Codes: H01M 10/633 characterised by algorithms, flow charts, software details or the like
• CPC Class Codes: H01M 2010/4278 Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
• CPC Class Codes: H01M 2200/10 Temperature sensitive devices
• CPC Class Codes: H01M 2220/20 : Batteries in motive systems, e.g. vehicle, ship, plane
• 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

A method of controlling the battery system of an electric vehicle includes detecting a thermal event in a first battery pack of a plurality of battery packs of the battery system, and at least partially powering down the electric vehicle automatically in response to the detected thermal event. The method may also include initiating a thermal rejection scheme in response to the detected thermal event.

Claims

1. A method of controlling the battery system of an electric vehicle, the battery system including a plurality of battery packs, each battery pack including multiple battery cells electrically coupled together, comprising:

detecting a thermal event in a first battery pack of the plurality of battery packs using an electronic controller of the electric vehicle;

at least partially powering down the electric vehicle automatically in response to the detected thermal event; and

initiating a thermal rejection scheme in response to the detected thermal event.

2. The method of claim 1, wherein initiating a thermal rejection scheme includes increasing a rate of cooling of the first battery pack relative to the rate of cooling of a second battery pack of the plurality of battery packs.

3. The method of claim 2, wherein increasing the rate of cooling includes increasing a flow of a coolant through the first battery pack relative to the flow of coolant through the second battery pack.

4. The method of claim 3, wherein increasing the flow of a coolant includes redirecting the flow of coolant from the second battery pack to the first battery pack.

5. The method of claim 1, further including displaying messages regarding the detected thermal event on a display device of the electric vehicle, the messages including at least one of a location of the detected thermal event, or instructions to exit the electric vehicle.

6. The method of claim 1, wherein at least partially powering down the electric vehicle includes turning off substantially all power from the battery system after a predetermined amount of time after detecting the thermal event.

7. The method of claim 1, wherein detecting a thermal event includes detecting the thermal event based on signals from one or more sensors located in the first battery pack.

8. The method of claim 1, wherein detecting a thermal event includes detecting the thermal event based on signals from a pressure sensor located in the first battery pack.

9. The method of claim 1, wherein detecting a thermal event includes detecting the thermal event based on signals from a humidity sensor located in the first battery pack.

10. A method of controlling the battery system of an electric vehicle, the battery system including a plurality of battery packs, each battery pack including multiple battery cells electrically coupled together, comprising:

receiving, at an electronic controller, data from one or more sensors coupled to each battery pack of the plurality of battery packs;

detecting, based on the received data, a thermal event in a first battery pack of the plurality battery packs;

electrically decoupling the first battery pack from the battery system in response to the detecting; and

increasing a rate of cooling of the first battery pack relative to the rate of cooling of a second battery pack of the battery system in response to the detecting.

11. The method of claim 10, further including turning off substantially all power from the battery system after a predetermined amount of time after detecting the thermal event.

12. The method of claim 10, further including sending information to an operator of the electric vehicle in response to the detecting, the information including instructions to evacuate the vehicle using an indicated exit of the electric vehicle.

13. The method of claim 10, further including wirelessly sending information regarding the detected thermal event to a location remote from the electric vehicle in response to the detecting.

14. The method of claim 10, wherein the receiving data includes receiving data indicative of a gas being released from one or more battery cells of the first battery pack.

15. The method of claim 10, wherein increasing a rate of cooling includes redirecting a flow of a coolant from the second battery pack to the first battery pack.

16. A method of controlling the battery system of an electric bus, the battery system including a plurality of battery packs, each battery pack including multiple battery cells electrically coupled together, comprising:

detecting, based on data received from one or more sensors coupled to each battery pack of the plurality of battery packs, a thermal event in a first battery pack of the plurality of battery packs;

sending information regarding the detected thermal event to an operator of the electric bus;

turning off substantially all power from the battery system after a predetermined amount of time after detecting the thermal event; and

increasing a rate of cooling of the first battery pack relative to the rate of cooling of a second battery pack of the plurality of battery packs in response to the detecting.

17. The method of claim 16, wherein the detecting includes detecting a thermal event based on data indicative of a gas being released from at least one battery cell of the multiple battery cells in the first battery pack.

18. The method of claim 17, further including receiving data indicative of a gas being released from at least one of (a) a pressure sensor, and (b) a humidity sensor.

19. The method of claim 16, wherein turning off substantially all power from the battery system includes sequentially turning off power to different systems of the bus at different times.

20. The method of claim 16, wherein increasing a rate of cooling includes redirecting a flow of a coolant from the second battery pack to the first battery pack.