Temperature control method and structure for a battery pack

• US 6,448,741 B1
• Filed: 03/05/2001
• Issued: 09/10/2002
• Est. Priority Date: 09/03/1998
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Eto, Toyohiko, Sekimori, Toshiyuki, Inui, Kiwamu
• Primary Examiner(s): Tso, Edward H.
• Assistant Examiner(s): TIBBITS, PIA FLORENCE
• Application Number:
  US09/763,622
• Time in Patent Office: 554 Days
• Field of Search: 320/107, 429/99, 429/120
• US Class Current: 320/107
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• 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 10/651 characterised by parameters specified by a numeric value or mathematical formula, e.g. ratios, sizes or concentrations
• CPC Class Codes: H01M 10/652 characterised by gradients for achieving a desired temperature gradient H01M10/617
• CPC Class Codes: H01M 10/6563 with forced flow, e.g. by blowers
• CPC Class Codes: H01M 10/658 by thermal insulation or shielding
• 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 50/56 Cup shaped terminals
• CPC Class Codes: H01M 6/42 Grouping of primary cells into batteries H01M6/40 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Cylindrical battery modules (9) composed of a plurality of serially connected cells (7) and arranged in parallel and stacked in piles within a holder case (10) are cooled with a forced current of air supplied from the underside. The battery modules (9a) located on the most upstream side of the air current are covered with film tubes (2), so as to prevent them from being cooled more than the other battery modules (9), thereby achieving uniformity in the temperatures of the battery modules. Temperature equalization is further improved by providing film tubes (2) to the several tiers of the battery modules such that the film tubes for covering upstream battery modules (9) have larger diameters than those for downstream battery modules.

Claims

1. A temperature control method for a battery pack wherein a plurality of battery modules comprising a plurality of serially connected cells are arranged in parallel and stacked in piles within a holder case, comprising the steps of:

providing a forced current of air into the holder case in a direction in which the battery modules are stacked; and

covering battery modules located on an upstream side of the air current with film tubes such as to form a gap between the battery module and the film tube, wherein said gap is made larger in battery modules which are located at a position farthest upstream along the direction of the air current.

2. A temperature control structure for a battery pack wherein a plurality of battery modules comprising a plurality of serially connected cells are arranged in parallel and stacked in piles within a holder case, comprising:

means for providing a forced current of air into the holder case in a direction in which the battery modules are stacked; and

a plurality of film tubes respectively fitted on a plurality of battery modules located on an upstream side of the air current such as to form a gap between the battery module and the film tube, wherein said gap is adjustable in size and made larger in battery modules which are located at a position farthest upstream along the direction of the air current.

3. The temperature control structure according to claim 2, wherein part of the battery module is provided with a spacer, and the film tube is fitted on the spacer for covering the battery module.

4. The temperature control structure according to claim 2, wherein the film tubes are made of a resin film formed in a cylindrical shape.

5. The temperature control structure according to claim 2, wherein the film tubes are formed of a resin film rolled into a cylindrical shape with both side edges thereof being overlapped and joined together, the resin film having a width greater than the circumference of a thus formed film tube covering the battery module with a gap therebetween.

6. The temperature control structure according to claim 2, wherein the battery modules are covered with film tubes having various diameters, the film tubes being formed of a resin film having such a width that when rolled into a cylindrical shape, the resin film surrounds the battery module with a largest gap therebetween.

7. A temperature control structure for a battery pack wherein a plurality of battery modules comprising a plurality of serially connected cells are arranged in parallel and stacked in piles within a holder case, comprising:

a device that provides a forced current of air into the holder case in a direction in which the battery modules are stacked; and

a plurality of film tubes respectively fitted on a plurality of battery modules located on an upstream side of the air current such as to form a gap between the battery module and the film tube, wherein said gap is adjustable in size and made larger in battery modules which are located at a position farthest upstream along the direction of the air current.

8. The temperature control structure according to claim 7, wherein part of the battery module is provided with a spacer, and the film tube is fitted on the spacer for covering the battery module.

9. The temperature control structure according to claim 7, wherein the film tubes are made of a resin film formed in a cylindrical shape.

10. The temperature control structure according to claim 7, wherein the film tubes are formed of a resin film rolled into a cylindrical shape with both side edges thereof being overlapped and joined together, the resin film having a width greater than the circumference of a thus formed film tube covering the battery module with a gap therebetween.

11. The temperature control structure according to claim 7, wherein the battery modules are covered with film tubes having various diameters, the film tubes being formed of a resin film having such a width that when rolled into a cylindrical shape, the resin film surrounds the battery module with a largest gap therebetween.