LITHIUM SECONDARY BATTERY AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To prevent reduction in an adhesive property of an active material, and to improve a charge/discharge cycle characteristic by setting the substantial surface area of at least one current collector surface of a negative electrode and a positive electrode not less than specific times the apparent surface area. SOLUTION: A positive electrode 1 is obtained by adhering a positive electrode active material 2 such as lithium cobalt oxide to a positive electrode current collector 1 such as aluminum foil. A negative electrode 6 is obtained by adhering a negative electrode active material 5 desirably containing scaly graphite or lump-shaped amorphous carbonaceous powder and metallic powder storing/releasing lithium ions to the surface of a negative electrode current collector 4 such as copper foil. These positive electrode 3 and negative electrode 6 are wound via a porous separator 7 to be housed in a battery can 10 filled with an organic solvent electrolyte. In that case, the substantial surface area of at least one surface of the current collectors 1, 4 is formed into two times or more of the appearance. This lithium secondary battery can obtain discharge capacity 85% or more after 200 cycles to discharge capacity 100% after charge/ discharge 5 cycles of a prescribed condition.