Structure and method for removing battery cell heat

• US 8,563,159 B2
• Filed: 08/04/2010
• Issued: 10/22/2013
• Est. Priority Date: 08/04/2010
• Status: Expired due to Fees

• Current Assignee: Bren-Tronics Batteries International, LLC
• Original Assignee: Bren-Tronics Batteries International, LLC
• Inventors: Meehan, Henry M.
• Primary Examiner(s): Alejandro, Raymond
• Application Number:
  US12/850,102
• Publication Number:
  US 20120034499A1
• Time in Patent Office: 1,175 Days
• Field of Search: 429/158, 429/160, 429/7, 429/120, 429/123, 429/121, 429/163, 429/159, 439/755, 439/754, 439/627, 439/504
• US Class Current: 429/158
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/647 Prismatic or flat cells, e.g. pouch cells
• CPC Class Codes: H01M 10/651 characterised by parameters specified by a numeric value or mathematical formula, e.g. ratios, sizes or concentrations
• CPC Class Codes: H01M 10/653 characterised by electrically insulating or thermally conductive materials
• CPC Class Codes: H01M 10/6553 Terminals or leads
• CPC Class Codes: H01M 10/6554 Rods or plates
• CPC Class Codes: H01M 50/209 adapted for prismatic or rectangular cells H01M50/216 takes precedence
• CPC Class Codes: H01M 50/502 Interconnectors for connecting terminals of adjacent batteries; Interconnectors for connecting cells outside a battery casing
• CPC Class Codes: H01M 50/503 characterised by the shape of the interconnectors
• CPC Class Codes: H01M 50/51 Connection only in series
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

An apparatus includes a thermal strap that connects a first terminal of a first battery cell and a second terminal of a second battery cell. The thermal strap has high thermal and electrical conductivity. A wall link connects the thermal strap to a wall having high thermal conductivity. The wall link includes a first portion having high thermal and electrical conductivity and a second portion having high thermal conductivity but low electrical conductivity. The second portion is located between the first portion and the wall.

Claims

1. A battery comprising:

a battery housing having a wall made from a thermal conductive metal material comprising a heat sink for the battery;

a first prismatic cell having a first positive terminal and a first negative terminal located within the battery housing;

a second prismatic cell having a second positive terminal and a second negative terminal adjacent the first cell within the battery housing;

a terminal strap electrically coupling the first positive terminal to the second negative terminal for transmitting electricity between the cells when the cells are under load; and

a wall link extending from the terminal strap thermo-mechanically connecting the coupled terminals to the wall for heat sinking, the wall link comprising a first portion connected to the terminal strap and a second portion connected between the first portion and the wall, wherein the second portion has an electrical conductivity at least 10⁶ times less than the first portion to electrically isolate the first portion from the wall.

2. The battery of claim 1, wherein the terminal strap and the first portion are formed from a unitary piece of material.

3. The battery of claim 1, wherein the first portion of the wall link has an electrical conductivity of at least about 10⁶ Siemens per meter.

4. The battery of claim 1, wherein the first portion of the wall link has a thermal conductivity of at least about 1.2 Watts per meter-degree Kelvin.

5. The battery of claim 1, wherein the second portion of the wall link has an electrical conductivity of less than about 1 Siemen per meter.

6. The battery of claim 1, wherein the second portion of the wall link has a thermal conductivity of at least about 1.2 Watts per meter-degree Kelvin.

7. The battery of claim 1, wherein the cells are prismatic lithium-ion cells.

8. The battery of claim 1, wherein under load the terminal strap transmits up to 800 amps of electrical current therethrough for at least 30 seconds with less than about a 2 degree Celsius rise in the temperature of the thermal terminal strap.

9. The battery of claim 1, wherein under load the terminal strap transmits up to 40 amps of electrical current therethrough at a steady state of 65 degrees Celsius, with less than about a 2 degree Celsius rise in the temperature of the terminal strap.

10. The battery of claim 3, wherein the second portion of the wall link has an electrical conductivity of less than about 1 Siemen per meter and a thermal conductivity of at least about 1.2 Watts per meter-degree Kelvin.

11. A battery comprising:

a battery housing having a wall comprising a heat sink for the battery, the wall having a thermal conductivity of above about 1.2 Watts per meter-degree Kelvin and an electrical conductivity of less than about 1 Siemen per meter;

a terminal strap electrically coupling a first positive terminal of a first prismatic cell to a second negative terminal of a second prismatic cell for transmitting electricity between the cells within the battery housing when the cells are under load; and

a wall link extending from the terminal strap thermo-mechanically connecting the coupled terminals to the wall for heat sinking, the wall link comprising a first portion connected to the terminal strap and a second portion connected between the first portion and the wall, wherein the second portion has an electrical conductivity at least 10⁶ times less than the first portion to electrically isolate the first portion from the wall, the wall link having a thermal conductivity of above about 1.2 Watts per meter-degree Kelvin.

12. The battery of claim 11, wherein the terminal strap and the wall link are formed from a unitary piece of material.

13. The battery of claim 11, wherein under load the terminal strap transmits up to 800 amps of electrical current therethrough for at least 30 seconds with less than about a 2 degree Celsius rise in the temperature of the terminal strap.

14. The battery of claim 11, wherein under load the terminal strap transmits up to 40 amps of electrical current therethrough at a steady state of 65 degrees Celsius, with less than about a 2 degree Celsius rise in the temperature of the terminal strap.