Sanyo Electric Co., Ltd.

Masanori Ogi

Masato Iwanaga

Syuichi Yamashita

Atsushi Kaiduka

Yukihiro Oki

Toyoshige Muto

Zensaku Yasutake

The nonaqueous electrolyte secondary battery includes a rolled electrode assemblyE formed by rolling a positive electrode plateand a negative electrode platewith a separatorinterposed therebetween, the separatoris fixed on the outermost periphery of the rolled electrode assemblyE with an adhesive tape for fixing a roll end, an exposed portion of a negative electrode substratewithout an active material mixture layeris placed on an outermost periphery side of the negative electrode plate, a negative electrode tabis connected to the negative electrode substrateon an outermost periphery side, and the adhesive tapeis not overlapped with a roll endof the positive electrode plateand a roll endof the negative electrode substrate. Thus the battery is seldom broken even when charging and discharging are repeatedly provided at high voltage.

Nonaqueous electrolyte secondary battery with rolled electrode assembly

The present invention provides a sealed batteryincluding an electrode bodyformed by winding a positive electrode plate, a negative electrode plateand a separatorinterposed therebetween so as to have a hollow portionat the center, a tube-shaped center pininserted in the hollow portion, a battery outer cancontaining the electrode body, an external terminalalso serving as a safety valveevacuating gas when a gas pressure in the battery outer canexceeds a predetermined value. A slitis formed on a peripheral surface of the center pin, and a cutout partis formed on at least an end of the center pinat the external terminalside.

Sealed battery

The center pinis cylindrical and tube-shaped, and each of the planes formed by the external surface of the center pinin the vicinity of the edgesandof the slitis angled toward the inside of the center pin. The edgesandare therefore arranged to be more inward than the imaginary circumference that complements the gap from the slitof the center pin, and consequently, the edgesandhave less possibility of contacting and damaging the spiral-wound electrode assemblyin the event an external force deforms the center pin Further, the planes formed by the external surface of the center pinin the vicinal areasandof the edgesandare angled so as to form an angle of no greater than 120 degrees.

Growing community of inventors

Tokushima, Japan

Masanori Ogi