Semiconductor Energy Laboratory Co., Ltd.

Daisuke Suzawa

Minoru Takahashi

Daisuke Furumatsu

Hirofumi Misono

Nozomi Uto

In the case where a film having lower strength than a metal can is used as an exterior body of a secondary battery, a current collector provided in a region surrounded by the exterior body, an active material layer provided on a surface of the current collector, or the like might be damaged when force is externally applied to the secondary battery. A secondary battery resistant to external force is provided. A cushioning material is provided in a region sandwiched by an exterior body of the secondary battery. Specifically, the cushioning material is provided on the periphery of an electrode group including a positive electrode current collector, a positive electrode active material layer formed on at least one surface of the positive electrode current collector, a separator, a negative electrode current collector, and a negative electrode active material layer formed on at least one surface of the negative electrode current collector.

Secondary battery and electronic device

The power storage device includes a positive electrode, a negative electrode, an electrolyte, and an exterior body. The positive electrode includes a positive electrode current collector and a positive electrode active material layer in contact with the positive electrode current collector. The negative electrode includes a negative electrode current collector and a negative electrode active material layer in contact with the negative electrode current collector. The positive electrode active material layer and the negative electrode active material layer overlap with each other. The positive electrode, the negative electrode, and the electrolyte are surrounded by the exterior body. When a length of the positive electrode active material layer is P, a width of the positive electrode active material layer is P, a length of the negative electrode active material layer is N, and a width of the negative electrode active material layer is N, P&#x3e;P, N&#x3e;N, and N&#x3e;P+N&#x2212;Pare satisfied.

Growing community of inventors

Atsugi, Japan

Daisuke Suzawa