Method and apparatus for transferring heat generated by a battery

• US 6,010,800 A
• Filed: 06/17/1998
• Issued: 01/04/2000
• Est. Priority Date: 06/17/1998
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Original Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Inventors: Krause, Stanley J., Stadnick, Steven J.
• Primary Examiner(s): Nuzzolillo, Maria
• Assistant Examiner(s): Crepeau, Jonathan
• Application Number:
  US09/098,849
• Time in Patent Office: 566 Days
• Field of Search: 429/120, 429/178, 429/179, 429/65
• US Class Current: 429/120
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/653 characterised by electrically insulating or thermally conductive materials
• CPC Class Codes: H01M 10/6551 Surfaces specially adapted for heat dissipation or radiation, e.g. fins or coatings
• CPC Class Codes: H01M 10/6552 Closed pipes transferring heat by thermal conductivity or phase transition, e.g. heat pipes
• CPC Class Codes: H01M 10/6553 Terminals or leads
• CPC Class Codes: H01M 50/209 adapted for prismatic or rectangular cells H01M50/216 takes precedence
• CPC Class Codes: H01M 50/249 specially adapted for aircraft or vehicles, e.g. cars or trains constructional details of batteries specially adapted for electric vehicles B60L50/64
• CPC Class Codes: H01M 50/55 on the same side of the cell
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

An apparatus and method for controlling the temperature of a battery used in a spacecraft or an electric vehicle are disclosed. The apparatus includes a thermal conductor, such as a thermally-conductive heat pipe or forced-fluid cooling loop, that is in thermal contact with thermally-conductive cell terminals of the battery, and a heat sink, such as a radiator. The inventive method includes operating the battery to generate and conduct heat to the thermally-conductive battery cell terminals. The generated heat is passed via conduction from the terminals to the thermal conductor. The heat is conducted through the thermal conductor to a heat sink which may be remotely located with respect to the battery. Preferably, the thermal conductor remains electrically insulated from the battery cell terminals and the heat sink.

Claims

1. A method of transferring heat generated in a battery, the method comprising the steps of:

(a) providing a thermal conductor, the conductor disposed in thermal contact with at least one thermally-conductive battery cell terminal and a heat sink, wherein the thermal conductor is a heat pipe partially filled with a heat transfer fluid, and wherein the generated heat vaporizes a portion of the fluid and the heat sink condenses the vaporized fluid;

(b) operating the battery to generate heat; and

(c) conducting the heat to the terminal(s);

wherein the thermal conductor is electrically insulated from the terminal(s) and heat sink, and wherein the generated heat is conducted from the terminal(s) and through the conductor to the heat sink.

2. The method of claim 1, wherein the heat is generated in one or more of the following battery heat sources selected from the group consisting of a cell terminal, a relay, a bypass diode, a cell interconnect, and cell electronics for charge or discharge control or voltage conversion.

3. The method of claim 2, wherein the battery comprises multiple cells, each of said cells having positive and negative thermally-conductive battery cell terminals.

4. The method of claim 3, wherein each cell terminal is in thermal contact with at least two other cell terminals.

5. The method of claim 4, wherein the thermal conductor is in thermal contact with each thermally-conductive cell terminal.

6. The method of claim 1, wherein the heat transfer fluid is a material selected from the group consisting of ammonia and dichlorofluoromethane.

7. The method of claim 1, wherein the heat transfer fluid circulates within the heat pipe by action of pressure gradients formed by vaporization of the fluid and by action of capillary forces on condensed fluid.

8. The method of claim 1, wherein the heat sink is a radiator.

9. The method of claim 1, wherein the heat sink is remotely located with respect to the terminal(s).

10. The method of claim 1, wherein the heat sink is located adjacent the terminal(s).

11. The method of claim 1, wherein the battery is selected from the group consisting of lithium ion batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-metal hydride batteries.

12. A method of transferring heat generated in a battery, wherein the battery comprises at least one thermally-conductive battery cell terminal, a heat pipe disposed in thermal contact with the terminal and a heat sink, the pipe being electrically insulated from the terminal and heat sink, and partially filled with a circulating heat transfer fluid, the method comprising the steps of:

(a) operating the battery to generate heat in the battery;

(b) passing the generated heat through the terminal, the generated heat vaporizing a portion of the circulating fluid; and

,

(c) allowing the vaporized fluid to flow along the pipe to a portion of the pipe in thermal contact with the heat sink, where the vaporized fluid condenses.

13. An apparatus for transferring heat generated in a battery, the battery comprising

a battery cell,

an outer casing around the battery cell, and

at least one battery terminal extending through a wall of the outer casing, the battery terminal having an interior end within the outer casing and an exterior end outside the outer casing, the interior end of the battery terminal being in communication with the battery cell,

wherein the apparatus for transferring heat generated in the battery comprises:

a heat sink; and

a thermal conductor disposed entirely exterior to the outer casing of the battery, the thermal conductor having

a first end in thermal communication with the exterior end of the battery terminal but electrically insulated from the exterior end of the battery terminal, and

a second end in thermal communication with the heat sink, wherein the thermal conductor comprises a heat pipe partially filled with a heat transfer fluid, and wherein heat introduced into the thermal conductor at its first end from the battery terminal vaporizes a portion of the fluid, and the heat sink in thermal communication with second end of the thermal conductor condenses the vaporized fluid.

14. The apparatus of claim 13, wherein the battery comprises multiple battery cells.

15. The apparatus of claim 13, wherein there are at least two battery terminals, each in thermal communication with the first end of the thermal conductor.

16. The apparatus of claim 13, wherein the conductor is constructed from one or more materials selected from the group consisting of aluminum, iron, stainless steel, carbon steel, nickel, and copper.

17. The apparatus of claim 13, wherein the heat sink is remotely located with respect to the terminal(s).