Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Hideya Asano

Tatsuya Hashimoto

Masatoshi Nagayama

Shozo Fujiwara

Hiroyuki Murai

Hajime Konishi

Masaya Okochi

Yutaka Kawatate

Hiroshi Matsuno

Yorihito Ohana

Ryoichi Tanaka

A positive electrode active material powder for a non-aqueous electrolyte secondary battery, wherein an amount of a liquid reagent absorbed by the powder is 20 to 40 ml per 100 g of the powder when the liquid reagent is dibutyl phthalate, and the amount is 20 to 50 ml per 100 g of the powder when the liquid reagent is N-methyl-2-pyrrolidone or water, the absorption amount is a value measured using a device according to test method A or B regarding DBP absorption based on JIS K6217 (1997), and the measured value is an amount of the liquid reagent added until the viscosity of a mixture of the powder and the liquid reagent reaches a level corresponding to 70% of a maximum torque which is recorded when a change in the viscosity of a mixture of the powder and the liquid reagent is measured by a torque detecting device.

Positive electrode active material, non-aqueous electrolyte secondary battery containing the same and method for evaluating positive electrode active material

A lithium ion secondary battery comprising a positive electrode, a negative electrode and a non-aqueous electrolyte, wherein the positive electrode comprises a positive electrode active material, a conductive agent and a binder, the positive electrode active material comprises a lithium-containing composite oxide represented by the formula Li(CoMgM)O, where M is at least one selected from Ni and Al, 0&#x2266;a&#x2266;1.05, 0.03&#x2266;x&#x2266;0.15, 0&#x2266;y&#x2266;0.25, 0.85&#x2266;b&#x2266;1.1 and 1.8&#x2266;c&#x2266;2.1, and the amount of the conductive agent contained in the positive electrode is not more than 3.0 parts by weight per 100 parts by weight of the positive electrode active material.

Lithium ion secondary battery

A battery, in which measures are taken to suppress a reduction in charge/discharge capacity and degradation of load characteristics due to peeling of an active material off the current collector during repeated charging and discharging, is disclosed. Boehmite treatment or chromate treatment of the current collector surface of the electrode plate for the battery suppresses the degradation of charge/discharge capacity and load characteristics.

Battery plate and battery

Growing community of inventors

Hirakata, Japan

Hideya Asano