| 摘要 |
PROBLEM TO BE SOLVED: To eliminate large reduction in battery capacity even if charge/ discharge is repeated many times, and to maintain an initial large discharge capacity by using LiMn2 O4 as a positive electrode active material, and using an electrolyte with dissolved LiBF4 as a support salt in an organic solvent composed of an ethylene carbonate and a chain carbonate. SOLUTION: A secondary battery is composed of a positive electrode using LiMn2 O4 as a positive electrode active material; an electrolyte with dissolved LiBF4 as support salt in an organic solvent composed of an ethylene carbonate and a chain carbonate; and a negative electrode. In this battery, even if charge/ discharge is repeated, elution of Mn from the positive electrode and decomposing reaction of the electrolyte on the negative electrode are restrained. The positive electrode active material is composed of an LiMn2 O4 particle and an electric conductor, and is desirably composed of a conductive layer coating surface of LiMn2 O4 particles. The specific surface area of the conductive layer is desirably 5 to 30 m<2> /g. In the negative electrode, a carbonaceous material is desirably used as a neagative electrode active material. |
