The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Oct. 14, 2008

Filed:

Oct. 27, 2004
Applicants:

Tsumoru Ohata, Kyoto, JP;

Shigeo Ikuta, Hirakata, JP;

Akiko Fujino, Suita, JP;

Tetsuya Hayashi, Kadoma, JP;

Kohei Suzuki, Yao, JP;

Inventors:

Tsumoru Ohata, Kyoto, JP;

Shigeo Ikuta, Hirakata, JP;

Akiko Fujino, Suita, JP;

Tetsuya Hayashi, Kadoma, JP;

Kohei Suzuki, Yao, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01M 2/18 (2006.01); H01M 2/16 (2006.01);
U.S. Cl.
CPC ...
Abstract

A lithium ion secondary battery has an electrode group including: a winding core; and a positive electrode and a negative electrode that are wound around the winding core. This electrode group does not have an independent separator between the positive and negative electrodes. A porous film is integrally formed on both sides of at least one of the positive electrode and the negative electrode. The negative electrode and the positive electrode are connected to the winding core by a negative electrode resin film and a positive electrode resin film, respectively. The use of such resin films makes it possible to reduce the breakage of the porous films and prevent a short-circuit between the positive and negative electrodes.


Find Patent Forward Citations

Loading…