LITHIUM ION SECONDARY BATTERY, AND METHOD OF MANUFACTURING LITHIUM ION SECONDARY BATTERY

摘要

A lithium ion secondary battery (1) includes: a positive electrode sheet (21) that includes a positive electrode active material layer (23) containing a positive electrode active material particle (24); a negative electrode sheet (31); and a nonaqueous electrolytic solution (40) that contains a compound containing fluorine, wherein a surface (24n) of the positive electrode active material particle (24) includes a film (25) containing fluorine and phosphorus, and a ratio Cf/Cp satisfies 1.89<=Cf/Cp<=2.61 where Cf represents the number of fluorine atoms in the film (25), and Cp represents the number of phosphorus atoms in the film (25).