| abstract |
A cell which utilizes spinel type lithium manganate as an active material and comprises a positive electrode containing a gelled polymer electrolyte (A), a negative electrode and a gelled polymer electrolyte (B) in a membrane or film form doubling as a separator, wherein the gelled polymer electrolytes (A and B) both comprises a polyalkylene oxide based polymer impregnated with a liquid electrolyte. The inventive cell has a large contact surface area between an active material of the positive electrode and a gelled polymer electrolyte due to a specific gelled polymer electrolyte (A) contained in the positive electrode, which results in its having a large initial discharge capacity (especially, a high rate discharge capacity). Further, in the inventive cell, the manganese in the spinel type lithium manganate shows a reduced tendency to dissolve out, due to a specific gelled polymer electrolyte (B) used as an electrolyte, which results in the reduction of the decrease in discharge capacity caused by the dissolution of manganese in a charge-discharge cycle, that is, in the excellent charge-discharge cycle characteristics of the cell. |