Panasonic Corporation

Tsuyoshi Hatanaka

Tetsuya Hayashi

Tatsuya Hashimoto

Yusuke Fukumoto

Hideaki Fujita

Kohei Suzuki

Masaharu Miyahisa

Noriko G Tanaka

Akira Nagasaki

Yoshiki Ohsawa

Kenichi Nishibata

Yasuhiko Yamasaki

A non-aqueous electrolyte secondary battery of the present invention comprises a long core member and a material mixture layer formed thereon. The electrode plate has an exposed part of the core member formed along one side which is parallel to the longitudinal direction of the core member. The material mixture layer comprises a material that can absorb and desorb lithium ions. A porous film is formed on at least a part of the exposed part of the core member adjacent to an edge face of the material mixture layer and on the material mixture layer and is parallel to the exposed portion of the core member, and the thickness of the porous film is greater at the edge face of the material mixture layer which is parallel to the exposed part of the core member and located on the side of the exposed part of the core member than at a central portion of the material mixture layer in the width direction thereof.

Electrode plate for non-aqueous electrolyte secondary battery and non-aqueous electrolyte secondary battery using the same

A sealed battery includes an electrode group formed by winding or stacking a positive electrode including a current collector carrying an active material layer thereon, a negative electrode including a current collector carrying an active material layer thereon and a separator interposed therebetween. The current collectors of the positive and negative electrodes are exposed at an end thereof and the exposed ends are welded to current collector terminals, respectively. The active material layers formed on the surfaces of the current collectors are covered with heat resistant porous films, respectively. An end face of the separator is flush with or positioned inside relative to end faces of the heat resistant porous films. The heat resistant porous films have a melting point higher than that of the separator and have a thermal conductivity lower than that of the current collectors.

Sealed battery

A safety mechanism for a laminate battery. An exterior case () consists of two molded sheets () made of laminate sheets, superposed upon one another, and bonded together around the outer edges. The exterior case has a protrusion () that communicates with the interior of the exterior case and protrudes outwardly from one side. A safety vent () is made up of an exhaust hole () formed in at lease one of the two molded sheets () in the protrusion (), and a valve element () making elastic pressure contact with the edge of the exhaust hole () to seal it. The safety mechanism does not operate within the range of internal pressure variation during normal use, but operates reliably at a time point when a predetermined valve operating pressure is reached to release a necessary amount of gas to the outside, this valve operating pressure being within the safe range relative to the pressure resistance of the exterior case () made of laminate sheets. Also, the safety vent configuration enables a reduction in production cost.

Safety mechanism for laminate battery

A lithium ion secondary battery which includes: a negative electrode platein which a negative electrode mixture layeris formed on each of both surfaces of a negative electrode current collectorcontaining copper as a principle component and having a sheet shape; a positive electrode platein which a positive electrode mixture layeris formed on each of both surfaces of a positive electrode current collectorcontaining aluminum as a principle component and having a sheet shape; and a separatorholding an electrolyte. The negative electrode plate, the positive electrode plateand the separatorare spirally wound or stacked. The thickness of the positive electrode current collectoris smaller than the thickness of the negative electrode current collector

Lithium ion secondary battery

A lithium ion secondary battery including: an electrode group including a belt-like positive electrode and a belt-like negative electrode that are wound with a separator interposed therebetween; and a can with a bottom for accommodating the electrode group, wherein the positive electrode has a positive electrode current collector and a positive electrode mixture layer carried on the positive electrode current collector, the negative electrode has a negative electrode current collector and a negative electrode mixture layer carried on the negative electrode current collector, and a porous heat-resistant layer is partially provided between the separator and at least one of the positive electrode mixture layer and the negative electrode mixture layer. Since a porous heat-resistant layer is thus placed, a high performance lithium ion secondary battery capable of efficiently preventing internal short circuit due to overheating while preventing decrease in battery characteristics can be provided.

Growing community of inventors

Wakayama, Japan

Tsuyoshi Hatanaka