| 摘要 |
PROBLEM TO BE SOLVED: To provide a lithium secondary battery having a high capacity, superior charge/discharge cycles and less increasing internal resistance by using a water-soluble polymer superior in organic solvent resistance, as a binder. SOLUTION: The lithium secondary battery comprises a positive electrode containing a positive electrode active material having LiNiO2 compound represented by a formula LixNi1-yMyO2, where M is at least one element selected from the group consisting of Co, Mn, All, B, Ti, Mg and Fe, 0<x<=1.2, and 0<y<=0.25, and the binder for binding the positive electrode active material, and an electrolyte, the BET specific surface area of the LiNiO2 compound being 0.65 m2/g or smaller, the binder having the water-soluble polymer having electrolyte non-swelling property and the positive electrode active material having the surface coated with the water-soluble polymer. The lithium secondary battery is superior in charge/discharge cycling property, with less lowering capacity, less increasing internal resistance and less lowering discharge capacity. |
