Battery module with a controllable external heat sink

• US 10,418,673 B2
• Filed: 03/03/2017
• Issued: 09/17/2019
• Est. Priority Date: 05/14/2014
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: Lux, Simon, Von Groll, Max
• Primary Examiner(s): Douyette, Kenneth J
• Application Number:
  US15/449,375
• Publication Number:
  US 20170179552A1
• Time in Patent Office: 928 Days
• CPC Class Codes: B60L 58/26 by cooling
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• 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 10/637 characterised by the use of reversible temperature-sensitive devices, e.g. NTC, PTC or bimetal devices; characterised by control of the internal current flowing through the cells, e.g. by switching means for preventing undesired use or discharge H01M50/572
• CPC Class Codes: H01M 10/655 Solid structures for heat exchange or heat conduction
• CPC Class Codes: H01M 10/6551 Surfaces specially adapted for heat dissipation or radiation, e.g. fins or coatings
• CPC Class Codes: H01M 10/657 by electric or electromagnetic means
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 50/581 in response to temperature
• 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 battery module having a controllable external heat sink and methods of operating the battery module are provided. According to an aspect of the invention, the battery module includes a battery cell, an external circuit connected to the battery cell, and a controller that controls the external circuit. The external circuit includes a first switch and a heat sink. If an internal short circuit within the battery cell is detected, the controller closes the first switch in order to generate heat in the heat sink.

Claims

1. A method of operating a battery module, the method comprising:

detecting an internal short circuit within a battery cell of the battery module in response to a voltage of the battery cell being below a voltage threshold;

confirming, separately from said detecting, the existence of the internal short circuit based on a current of the battery cell; and

closing, in response to said detecting and confirming the internal short circuit, a first switch within an external circuit connected to the battery cell in order to generate heat in a heat sink within the external circuit.

2. The method according to claim 1, further comprising isolating the battery cell from a plurality of other battery cells within the battery module.

3. The method according to claim 1, further comprising opening a second switch within the external circuit in order to interrupt a bus current to the battery cell.

4. The method according to claim 3, further comprising interrupting the bus current to a plurality of other battery cells within the battery module.

5. The method according to claim 1, wherein a resistance of the heat sink is smaller than a resistance of a dendrite causing the internal short circuit.

6. The method according to claim 1, wherein a resistance of the heat sink is equal to or greater than a resistance of a dendrite causing the internal short circuit.

7. The method according to claim 1, further comprising maintaining the first switch in a closed state after the internal short circuit is detected, until a temperature of the battery cell is below a temperature threshold.

8. The method according to claim 1, wherein after the first switch is closed, more heat is generated in the heat sink than in the battery cell.

9. The method according to claim 1, wherein confirming the existence of the internal short circuit comprises confirming the existence of the internal short circuit when the current of the battery cell is measured as zero.

10. The method according to claim 1, wherein the threshold voltage is an absolute value or a percentage of voltage in a normal operating state before the detected internal short circuit.