Preventing Cell Thermal Runaway Propagation Within a Battery

• US 20130071717A1
• Filed: 09/19/2011
• Published: 03/21/2013
• Est. Priority Date: 09/19/2011
• Status: Active Grant

• Current Assignee: Wisk Aero LLC (The Boeing Co.)
• Original Assignee: Zee.Aero Inc.
• Inventors: Muniz, Thomas P.
• Granted Patent: US 8,993,145 B2
• Time in Patent Office: Days
• US Class Current: 429/120
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/617 for achieving uniformity or desired distribution of temperature
• CPC Class Codes: H01M 10/6551 Surfaces specially adapted for heat dissipation or radiation, e.g. fins or coatings
• CPC Class Codes: H01M 10/6555 arranged between the cells
• CPC Class Codes: H01M 10/658 by thermal insulation or shielding
• CPC Class Codes: H01M 50/24 adapted for protecting batteries from their environment, e.g. from corrosion thermal insulation H01M10/658
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A cell undergoing a thermal runaway process is characterized by high local temperatures at the cell. Thermal insulator prevents the high temperatures from dissipating to nearby cells such that thermal runaway is triggered in the nearby cells. In addition, thermal conductors are provided that form conduction paths that draw heat from a cell undergoing thermal runaway and distribute the heat to other cells in manner that thermal runaway is not triggered in cells that are near the failing cell. If sufficient heat is drawn away from a failing cell, temperatures of the cells surrounding the failed cell can remain low enough to prevent the surrounding cells from undergoing the thermal runaway process.

Claims

1. A battery comprising:

a plurality of battery cells arranged in a column, and comprising an alternating series of first cells and second cells, each of the cells having a top and bottom side and a left and right side, each cell having a maximum expected peak temperature caused by thermal runaway;

an insulator in contact with each cell and preventing direct physical contact between each first cell and an adjacent second cell;

a first thermal bus having a substantially planar portion to the left side of each first cell and a plurality of flanges extending away from the planar portion, each flange coupled to the top of one of the first cells, the first thermal bus constructed of a metal having a melting point higher than the maximum expected peak temperature; and

a second thermal bus having substantially planar portion to the right side of each second cell and a plurality of flanges extending away from the planar portion, each flange coupled to the top of one of the second cells, the second thermal bus constructed of a metal having a melting point higher than the maximum expected peak temperature.

2. The battery of claim 1 wherein the plurality of cells are lithium ion cells including a polymer electrolyte.

3. The battery of claim 1 wherein the plurality of cells are lithium ion cells including a liquid electrolyte.

4. The battery of claim 1 wherein the first thermal bus and the second thermal bus are constructed from aluminum.

5. The battery of claim 1 wherein the first thermal bus and the second thermal bus are constructed from graphite.

6. The battery of claim 1 wherein the first thermal bus and the second thermal bus are constructed from graphene.

7. The battery of claim 1 wherein the first thermal bus and the second thermal bus are constructed from carbon fiber.

8. The battery of claim 1 wherein the first thermal bus and the second thermal bus are constructed using carbon nanotubes.

9. The battery of claim 1 wherein the first thermal bus and the second thermal bus are constructed from silver.

10. The battery of claim 1 wherein the column of cells are contained within a first cell assembly, and the battery further comprises a second plurality of cells arranged in a second column, the second column contained within a second cell assembly, the second cell assembly coupled to the first cell assembly by a third thermal bus.

11. The battery of claim 1 wherein the insulator includes a ceramic fiber.

12. The battery of claim 11 wherein the ceramic fiber is an aluminum oxide fiber.

13. The battery of claim 1 wherein the insulator includes a silica aerogel material.

14. The battery of claim 1 wherein the insulator includes fiberglass fabric.

15. A battery comprising:

a plurality of battery cells arranged in a column, each of the cells having a top and bottom side and a left and right side, each cell having a maximum expected peak temperature caused by thermal runaway;

an insulator in contact with each cell and preventing direct physical contact between each cell and an adjacent cell;

a first thermal bus having a substantially planar portion to the left side of each cell, the first thermal bus constructed of a metal having a melting point higher than the maximum expected peak temperature;

a second thermal bus having a substantially planar portion to the right side of each cell, the second thermal bus constructed of a metal having a melting point higher than the maximum expected peak temperature; and

a plurality of flanges, each flange substantially planar to the bottom side of each cell and connecting the first thermal bus to the second thermal bus, each flange in contact with the insulator below one of the cells and the insulator above an adjacent one of the cells, the flanges constructed of a metal having a melting point higher than the maximum expected peak temperature.