The present invention uses a mixture of spherical carbonaceous materials
having different average particle sizes as an anode active material in an
anode composite mixture layer of an anode. The spherical carbonaceous
material of large particle size decreases the reaction with non-aqueous
electrolyte solution to suppress the decrease in battery capacity, form
clearances having suitable sizes in the anode composite mixture layer,
and retain the non-aqueous electrolyte solution. The clearances in the
anode composite mixture layer are efficiently filled with the
carbonaceous material of small particle size while spaces capable of
suitably retaining the non-aqueous electrolyte solution are left
unfilled. Thus, the volume density of the anode composite mixture layer
is improved and the battery capacity is increased. Accordingly, energy
density can be increased without deteriorating battery characteristics.