LITHIUM ION SECONDARY BATTERY AND METHOD FOR MANUFACTURING LITHIUM ION SECONDARY BATTERY

摘要

Disclosed is a lithium ion secondary battery which comprises a positive electrode, a negative electrode, a separator arranged between the positive electrode and the negative electrode, and a nonaqueous electrolyte solution. The lithium ion secondary battery is characterized in that the nonaqueous electrolyte solution contains a nonaqueous solvent containing a sulfone compound; that the positive electrode contains a positive electrode collector and a positive electrode active material layer that is formed on the surface of the positive electrode collector; that the positive electrode active material layer contains lithium-containing complex oxide particles and a fluororesin; and that the coverage of the surface area of the lithium-containing complex oxide particles by the fluororesin is 20-65%. The lithium ion secondary battery is suppressed in deterioration of the rate characteristics over time, particularly in significant deterioration of the rate characteristics in cases when the lithium ion secondary battery is stored at high temperatures.