Tunable frangible battery pack system

• US 20080241667A1
• Filed: 03/31/2007
• Published: 10/02/2008
• Est. Priority Date: 03/31/2007
• Status: Active Grant

• Current Assignee: Tesla Inc.
• Original Assignee: Tesla Motors Incorporated (Tesla Inc.)
• Inventors: Kohn, Scott, Hewett, Brian Charles, Berdichevsky, Gene
• Granted Patent: US 7,923,144 B2
• Time in Patent Office: Days
• US Class Current: 429/159
• CPC Class Codes: B60L 2240/545 Temperature
• 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 50/64 Constructional details of batteries specially adapted for electric vehicles
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: B60L 58/26 by cooling
• CPC Class Codes: H01M 50/213 adapted for cells having curved cross-section, e.g. round or elliptic H01M50/209, H01M50/216 take precedence
• CPC Class Codes: H01M 50/227 Organic material
• 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 50/298 characterised by the wiring of battery packs
• CPC Class Codes: H01M 50/503 characterised by the shape of the interconnectors
• CPC Class Codes: H01M 50/522 Inorganic material
• CPC Class Codes: H01M 50/574 Devices or arrangements for the interruption of current
• CPC Class Codes: H01M 50/579 in response to shock
• 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 tunable frangible battery pack system for use in an electric vehicle is disclosed. The tunable frangible battery pack system includes a two piece clamshell housing. The system also includes a plurality of battery cells arranged within the housing and a collector plate secured to each piece of the housing. The system also includes a wire conductor arranged between each of the battery cells and collector plates to create a frangible disconnect system when the battery pack system and electric vehicle are exposed to a predetermined mechanical or thermal force or event.

Claims

1. A frangible battery pack system, said battery pack system comprising:

a housing;

a plurality of battery cells arranged within said housing;

a collector plate arranged on each end of said housing; and

a conductor arranged between said collector plate and said battery cell.

2. The battery pack system of claim 1 wherein said housing is a two piece clamshell having a plurality of counterbores, one of said battery cells is arranged within each counterbore.

3. The battery pack system of claim 1 wherein said housing is made of a plastic material.

4. The battery pack system of claim 2 wherein said counterbores having an orifice therein to expose the ends of said battery cells.

5. The battery pack system of claim 1 wherein said collector plate is made of a material that will conduct electricity.

6. The battery pack system of claim 5 wherein said collector plate is a nickel plated aluminum or copper.

7. The battery pack system of claim 1 wherein said conductor is a frangible wire, said conductor will break when the battery pack is exposed to a predetermined force or heat thus disconnecting said battery cells from said collector plate.

8. The battery pack system of claim 7 wherein said conductor is made of an aluminum alloy.

9. The battery pack system of claim 8 wherein said conductor having a predetermined percentage of magnesium and nickel.

10. The battery pack system of claim 9 wherein said magnesium is approximately 0.5% of said conductor and said nickel constitutes approximately 50 parts per million of said conductor.

11. The battery pack system of claim 1 wherein said conductor is arranged between said each battery cell and said collector plate.

12. The battery pack system of claim 11 wherein said wire conductor is bonded to said battery cell and said collector plate.

13. The battery pack system of claim 12 wherein said bond is made by an ultrasonic wedge process.

14. The battery pack system of claim 1 wherein said conductor having a circular cross section or ribbon like shape.

15. The battery pack system of claim 1 further comprising a silicone dielectric gel arranged around said battery cells.

16. A tunable frangible battery pack system for use in an electric vehicle, said battery pack system comprising:

a two piece clamshell housing;

a plurality of battery cells arranged within said housing;

a collector plate secured to each piece of said housing; and

a wire conductor arranged between each of said battery cells and said collector plates.

17. The battery pack system of claim 16 wherein said wire conductor is made from an aluminum alloy material having a predetermined percentage of magnesium and nickel.

18. The battery pack system of claim 17 wherein said wire conductor having a predetermined thickness or diameter which allows for said wire to be tunable to fail and break at a predetermined force or temperature thus disconnecting said battery cells from said collector plate.

19. The battery pack system of claim 16 wherein said wire conductor is bonded to said battery cell and said collector plate by an ultrasonic wedge bonding process.

20. The battery pack system of claim 16 further comprising a silicone dielectric gel arranged around said battery cells.

21. The battery pack system of claim 16 wherein said housing having a plurality of orifices therein for exposing an end of said battery cell.

22. The battery pack system of claim 21 wherein said collector plates having a plurality of orifices therein which align with said orifices in said housings, said wire conductors arranged through said orifices.

23. The battery pack system of claim 22 wherein said collector plate is secured to said housing by heat staking or epoxy, said collector plate having a recessed area adjacent to said orifices in said collector plate, said conductor arranged within said recessed area on one end thereof.

24. The battery pack system of claim 16 wherein said housing is made of a plastic.

25. The battery pack system of claim 16 wherein said collector plates are made of a metal.

26. The battery pack system of claim 16 wherein said wire conductor having a diameter in the range of 0.012 inches to 0.015 inches.