Tdk Corporation

Bungo Sakurai

Yukio Takahashi

Takuya Aoki

Masahiro Saegusa

Hidenobu Umeda

Ko Ito

Akinori Ohi

Tatsuya Shimazaki

Hirokazu Ohnuma

A separator according to the embodiment includes a porous base material having a thermoplastic resin. The porous base material has a heat-resistant porous layer on at least one surface thereof. The heat-resistant porous layer contains inorganic particles, a resin, and sulfur. A lithium ion secondary battery according to the embodiment, includes: the separator interposed between a positive electrode and a negative electrode; and an electrolyte solution. The heat-resistant porous layer is disposed between the positive electrode and the porous base material. Sulfur is distributed unevenly in the heat-resistant porous layer so as to exist in larger amount near a surface thereof opposite to the porous base material.

Separator and lithium ion secondary battery including the same

There can be provided an NiCuZn-based ferrite material containing an iron oxide, a copper oxide, zinc oxide and a nickel oxide in predetermined amounts as main components and a bismuth oxide, a silicon oxide, magnesium oxide and a cobalt oxide in predetermined amounts as additional components. Due to the predetermined amounts of the additional components, the ferrite material has an extremely good temperature characteristic (a change in permeability along with a change in temperature is small), a high quality coefficient Q and high strength.

Ferrite material

Growing community of inventors

Tokyo, Japan

Bungo Sakurai