Disclosed is a non-aqueous electrolyte secondary battery having an excellent
preservation characteristic at a high temperature and charging/discharging cycle
characteristic. A rolled body in which a strip-shape positive electrode and negative
electrode are rolled with a separator in-between is provided inside a battery can.
The positive electrode contains LixMn2-yMayO4
(where, Ma is at least one element selected from the group consisting of metal
elements other than Mn, and B) and LiNi1-zMbzO2 (where,
Mb is at least one element selected from the group consisting of metal elements
other than Ni, and B). By replacing part of Mn and Ni with other elements, the
crystal structure can be stabilized. Thereby, the capacity retention ratio after
preservation at a high temperature, and a heavy load discharging power under a
high electric potential cutoff can be improved. The mean particle size of particles
of the above-mentioned oxides are preferable to be 30 m and below so that
an excellent charging/discharging cycle characteristic can be obtained.
