Positive electrode active material and non-aqueous electrolyte secondary cell

Abstract

A non-aqueous electrolyte secondary cell having superior high temperature-operation properties and excellent large current-discharge properties is provided. The non-aqueous electrolyte secondary cell has a positive electrode composed of a positive electrode collector and positive electrode active material layers formed thereon. A positive electrode active material contained in the above layer is formed of a first composite oxide and a second composite oxide mixed therewith. The first composite oxide is formed of grains of a first lithium transition metal composite oxide containing at least nickel as a transition metal and a cover layer formed on at least part of the surface of each of the grains for suppressing decomposition of an electrolyte caused by the first lithium transition metal composite oxide. The second composite oxide is composed of grains of a second lithium transition metal composite oxide.

Description

technical field

[0001] The present invention relates to a positive electrode active material containing lithium and nickel as main components and a nonaqueous electrolyte secondary battery using the above positive electrode active material. Background technique

[0002] In recent years, various portable electronic devices, such as video cameras, mobile phones, and notebook computers, have entered the market and demand is increasing. With the trend of compactness and light weight of electronic devices, in order to increase energy density, research and development of batteries used as portable power sources, especially research and development of secondary batteries, have been actively conducted. Compared with related aqueous electrolyte solution secondary batteries, such as lead batteries, nickel-cadmium batteries, and nickel-metal hydride batteries, lithium-ion batteries are in high demand because of their high energy density, and in addition, when the environmental toleranc...

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