NEGATIVE ELECTRODE FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERIES, AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

The present invention provides a positive electrode active material which has improved capacity retention rate at room temperature. A negative electrode contained in a nonaqueous electrolyte secondary battery according to the present invention contains a negative electrode active material and a lithium sulfonate salt represented by general formula (I); and the particle diameter of the lithium sulfonate salt is 1 nm to 1,000 nm. (In the formula, R presents an n-valent aliphatic hydrocarbon group having 1 to 5 carbon atoms; and n represents 1 or 2.)