Patent ID: 8568928

Claim:
A non-aqueous electrolyte secondary battery comprising: a negative electrode comprising graphite as a negative electrode active material; a non-aqueous electrolyte; and a positive electrode having a positive electrode mixture layer comprising a positive electrode active material, a binder agent, and a conductive agent, wherein: the positive electrode active material of the positive electrode mixture layer comprises an olivine-type lithium-containing metal phosphate represented by the general formula Li x MPO 4 , where M is at least one element selected from the group consisting of Co, Ni, Mn, and Fe, and x is 0≦x≦1.3; and the conductive agent of the positive electrode mixture layer comprises a mixture of carbon particles and carbon fiber, wherein the carbon particles are carbon black; the carbon fiber has a diameter of 50-300 nm, a length of 5-100 μm and a specific surface area of 30 m 2 /g or less, and the amount of the carbon particles in the conductive agent is within the range of from 2 wt. % to 8 wt. % with respect to the total weight of the positive electrode mixture layer.