Title:
FLAT NONAQUEOUS SECONDARY BATTERY
Document Type and Number:
WIPO Patent Application WO/2012/014422
Kind Code:
A1
Abstract:
The present invention relates to a flat nonaqueous secondary battery in which a laminated electrode body including positive and negative electrode plates equipped with active materials and a porous insulator between the positive and negative electrode plates is wound to form an electrode group having a flat-shaped cross-section and consisting of a plate-shaped straight portion and a pair of curved corner portions.
The secondary battery is getting widely used as a power supply for portable electronic devices, but it is desired to further increase the capacity thereof as recent electronic devices are becoming more and more multifunctional. In order to increase the capacity, the electrode plates are pressed to a specified thickness by using, for example, a press, thereby increasing the densities of the active materials. However, there has been a problem that when the densities of the active materials are increased, the electrode plates tend to expand during charging and discharging, so that, as a result, the thickness of the electrode group increases and exceeds the upper limit of the specified thickness.
The present invention solves the above problem in such a way that in at least two adjacent gaps of the laminated electrode body at the corner portions of the secondary battery, the gap on the inner circumferential side is made larger than the gap on the outer circumferential side.
Inventors:
ISHIKAWA, Toshiki (())
Application Number:
JP2011/004146
Publication Date:
February 02, 2012
Filing Date:
July 22, 2011
Export Citation:
Assignee:
PANASONIC CORPORATION (1006, Oaza Kadoma Kadoma-sh, Osaka 01, 〒5718501, JP)
パナソニック株式会社 (〒01 大阪府門真市大字門真１００６番地 Osaka, 〒5718501, JP)
パナソニック株式会社 (〒01 大阪府門真市大字門真１００６番地 Osaka, 〒5718501, JP)
International Classes:
H01M10/0587; H01M10/0566
Attorney, Agent or Firm:
MAEDA, Hiroshi et al. (Osaka-Marubeni Bldg, 5-7Hommachi 2-chome, Chuo-ku, Osaka-sh, Osaka 53, 〒5410053, JP)
Claims: