APPARATUS FOR PROVIDING BATTERY PACK COOLING

• US 20150303531A1
• Filed: 11/23/2012
• Published: 10/22/2015
• Est. Priority Date: 11/23/2012
• Status: Active Grant

• Current Assignee: Husqvarna AB (HUSQVARNA)
• Original Assignee: Husqvarna AB (HUSQVARNA)
• Inventors: Willgert, Mikael, Dernebo, Lars, Mehra, Rajinder, Larsn, Martin
• Granted Patent: US 11,495,840 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 10/643 Cylindrical cells
• 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 10/6557 arranged between the cells
• CPC Class Codes: H01M 10/6563 with forced flow, e.g. by blowers
• CPC Class Codes: H01M 10/659 by heat storage or buffering, e.g. heat capacity or liquid-solid phase changes or transition
• 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: H02J 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/0045 concerning the insertion or the connection of the batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery pack may include a plurality of battery cells, a cell retainer and a heat exchanger assembly. The cell retainer may define a plurality of cell reception slots configured to retain respective ones of the battery cells. The cell retainer may define an enclosure that fixes the battery cells and is not penetrated by any cooling apparatus. The cell retainer may be in thermal communication with the battery cells to transfer heat away from the battery cells. The heat exchanger assembly may be in thermal communication with the cell retainer and external to the cell retainer to at least passively transfer heat away from the cell retainer while the battery pack is operated in a discharge mode. The cell retainer may include a thermally conductive material capable of transferring heat to the heat exchanger assembly and also storing at least some of the heat.

Claims

1. A battery pack comprising:

a plurality of battery cells;

a cell retainer defining a plurality of cell reception slots configured to retain respective ones of the battery cells, the cell retainer defining an enclosure that fixes the battery cells and is not penetrated by any cooling apparatus, the cell retainer being in thermal communication with the battery cells to transfer heat away from the battery cells; and

a heat exchanger assembly in thermal communication with the cell retainer and external to the cell retainer to at least passively transfer heat away from the cell retainer while the battery pack is operated in a discharge mode,

wherein the cell retainer comprises a thermally conductive material capable of transferring heat to the heat exchanger assembly and also storing at least some of the heat.

2. The battery pack of claim 1, wherein the heat exchanger assembly supports passive cooling only while the battery pack is operated in a discharge mode and supports active cooling while the battery pack is being charged.

3. The battery pack of claim 2, wherein the cell reception slots are disposed parallel to each other along a first direction, and wherein the active cooling is provided via air flow provided proximate to the heat exchanger assembly such that the air flow is directed parallel to the first direction.

4. The battery pack of claim 1, wherein the battery pack further comprises a cover disposed to contain the cell retainer and the heat exchanger assembly.

5. The battery pack of claim 4, wherein the heat exchanger assembly comprises a plurality of fins extending between a surface of the cell retainer and the cover.

6. The battery pack of claim 5, wherein the cell retainer and the heat exchanger assembly are formed from a single unitary piece of material.

7. The battery pack of claim 5, wherein the heat exchanger assembly and the cover are formed from a single unitary piece of material.

8. The battery pack of claim 1, wherein the heat exchanger assembly comprises at least an external surface of lateral sides of the battery pack.

9. The battery pack of claim 8, wherein the heat exchanger assembly extends parallel to at least a portion of a sidewall of a charger cavity into which the battery pack is insertable for charging.

10. The battery pack of claim 1, wherein the heat exchanger assembly receives a forced flow of air from a fan of a battery charger while the battery pack is being charged, and passively transmits heat to an environment of the battery pack while the battery pack is being discharged.

11. The battery pack of claim 1, wherein the cell retainer comprises a metallic or thermally conductive plastic enclosure disposed around all lateral sides of the battery cells, and wherein longitudinal ends of the cell retainer are sealed.

12. The battery pack of claim 1, wherein the cell retainer comprises a plurality of parts disposed adjacent to each other to form the continuous peripheral enclosure.

13. The battery pack of claim 1, wherein the cell retainer comprises a plurality of parts disposed adjacent to each other to form the enclosure, and wherein spaces are provided between at least some of the parts to account for thermal expansion or contraction of the cell retainer or the battery cells.

14. The battery pack of claim 1, wherein the cell retainer comprises a thermal interface material disposed in the cell reception slots between the battery cells and the cell retainer.

15. The battery pack of claim 1, wherein the cell retainer comprises one or more reception cavities encapsulating a phase change material.

16. A battery pack charging system comprising:

a battery charger; and

a battery pack receivable into the battery charger for charging of the battery pack, the battery pack comprising;

a plurality of battery cells;

a cell retainer defining a plurality of cell reception slots configured to retain respective ones of the battery cells, the cell retainer defining an enclosure that fixes the battery cells and is not penetrated by any cooling apparatus, the cell retainer being in thermal communication with the battery cells to transfer heat away from the battery cells; and

a heat exchanger assembly in thermal communication with the cell retainer and external to the cell retainer to at least passively transfer heat away from the cell retainer while the battery pack is operated in a discharge mode,

wherein the cell retainer comprises a thermally conductive material capable of transferring heat to the heat exchanger assembly and also storing at least some of the heat.

17. The battery pack charging system of claim 16, wherein the heat exchanger assembly supports passive cooling only while the battery pack is operated in a discharge mode and supports active cooling while the battery pack is being charged.

18. The battery pack charging system of claim 17, wherein the cell reception slots are disposed parallel to each other along a first direction, and wherein the active cooling is provided via air flow provided proximate to the heat exchanger assembly such that the air flow is directed parallel to the first direction.

19. The battery pack charging system of claim 16, wherein the battery pack further comprises a cover disposed to contain the cell retainer and the heat exchanger assembly.

20-35. -35. (canceled)

36. A method of cooling a battery pack, the method comprising:

providing a cell retainer defining a plurality of cell reception slots configured to retain respective ones of a plurality of battery cells, the cell retainer being in thermal communication with the battery cells and defining an enclosure that fixes the battery cells and is not penetrated by any cooling apparatus, the cell retainer comprising a thermally conductive material capable of transferring heat to the heat exchanger assembly and also storing at least some of the heat; and

providing a heat exchanger assembly in thermal communication with and external to the cell retainer to at least passively transfer heat away from the cell retainer while the battery pack is operated in a discharge mode.

37. (canceled)

38. (canceled)