METHOD OF PRODUCING LITHIUM-ION BATTERY

(A) An electrolyte solution containing lithium bis(oxalato)borate and vinylene carbonate is injected into a lithium-ion battery. (B) Initial charging is performed. (C) Aging is performed. During the aging, lithium bis(oxalato)borate and vinylene carbonate contained in the electrolyte solution are degraded. After the aging, in the electrolyte solution, a mass fraction of lithium bis(oxalato)borate is less than 0.10% and a mass fraction of vinylene carbonate is less than 0.10%.