To provide a nonaqueous electrolyte composition enhancing discharge capacity retention factor in repeated charge discharge cycles, and to provide a nonaqueous electrolyte secondary battery using the nonaqueous electrolyte composition.

The nonaqueous electrolyte composition contains an electrolyte salt, a nonaqueous solvent, and a chain carbonate having a 13-20C hydrocarbon group or halogenated hydrocarbon group, and may contain a carbonate having a hydrocarbon group having a double bond or a polymer compound. The nonaqueous electrolyte secondary battery is equipped with a positive electrode and a negative electrode using a material capable of absorbing and releasing lithium ions as a positive active material and a negative active material respectively, the nonaqueous electrolyte composition, a separator, and an outer packaging member for housing them.

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