Pre-charge / discharge method for lithium ion secondary battery and lithium ion secondary battery

摘要

PPROBLEM TO BE SOLVED: To provide a lithium-ion secondary battery having a lithium complex oxide of an olivine type structure as a positive electrode active material in which variations of discharge capacity due to history of charge and discharge even of the same SOC are controlled. PSOLUTION: Immediately after assembling of the lithium-ion secondary battery having a negative electrode, a positive electrode having a lithium complex oxide of an olivine type structure as a positive electrode active material, and a non-aqueous electrolytic solution interposed between the negative electrode and the positive electrode, charge and discharge in which the potential of the positive electrode at the time of charge completion becomes 4.1 V to the lithium metal and the potential of the positive electrode at the time of discharge completion becomes 2.5 V to the lithium metal are repeated 500 cycles at 2C rate. PCOPYRIGHT: (C)2010,JPO&INPIT