Non-aqueous electrolyte secondary battery

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 LixMPO4, 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 m2/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.