| 摘要 |
PROBLEM TO BE SOLVED: To prevent capacity reduction resulting from the repetition of charge and discharge cycles or storage in a lithium ion secondary battery which uses lithium manganese oxide as positive active material. SOLUTION: A free acid adsorption layer 1c is formed on a positive active material layer 1b. The free acid adsorption layer 1c is formed by evaporating solvent after, for example, α-Al2 O3 fine particles of 1.0μm in average particle diameter are dispersed together with a binder in the solvent, and the same is uniformly applied to the surface of the positive active material 1b. The separator 3 is interposed between the free acid adsorption layer 1c of a positive electrode 1 and the active material layer 2b of a negative electrode so as to assemble the battery. |
