Murata Manufacturing Co., Ltd.

Noriaki Kokubu

Kunio Sodeyama

Takao Mori

Kazuhiko Suzuki

Kosuke Yanagida

Yu Nomura

Hidehiko Wakui

A secondary battery including an electrode wound body having a structure in which a band-shaped positive electrode and a band-shaped negative electrode are stacked and wound with a separator interposed therebetween, an electrolyte solution, a battery can that accommodates the electrode wound body and the electrolyte solution, a battery lid that closes an open end portion of the battery can, and a safety valve mechanism provided between the battery lid and the electrode wound body, wherein the safety valve mechanism includes at least a safety cover, an outer peripheral portion of the battery lid and an outer peripheral portion of the safety cover are joined, and an area of a region where the outer peripheral portion of the battery lid and the outer peripheral portion of the safety cover are joined is 18.1% or more and 25.0% or less of a sectional area of the battery in a radial direction.

Secondary battery, method for manufacturing secondary battery, electronic device, and electric tool

A battery includes a safety valve configured to cause a deformation due to an increase in internal pressure of the battery; a restraining part including a plurality of first protrusions provided along a first circumference to serve as a restrainer against a lead part when the safety valve and the lead part are shut off due to deformation of the safety valve; and an insulating holder including a plurality of second protrusions provided along a second circumference to insulate the safety valve and the restraining part, where a number of the first protrusions and the second protrusions arranged on a diagonal line including the first circumference and the second circumference is 3 or less.

Battery, electric storage device, electric vehicle

Growing community of inventors

Kyoto, Japan

Noriaki Kokubu