LITHIUM-ION SECONDARY BATTERY

摘要

Disclosed is a lithium-ion secondary battery which includes a carbonaceous material in an anodic active material mix, and a cyclic carbonate and a chain carbonate both in an electrolytic solution. The solvent contains an additive which is a substance having a LUMO energy determined through molecular orbital calculation of lower than the LUMO energy of ethylene carbonate determined through molecular orbital calculation and having a HOMO energy lower than the HOMO energy of vinylene carbonate determined through molecular orbital calculation, the electrolytic solution contains LiPF 6 or LiBF 4 as an electrolyte, and the electrolytic solution shows a reduction-reaction current of -0.05 mA/cm 2 (provided that a reaction current on the reducing side be negative) or less at a potential lower than 1 V and shows an oxidation-reaction current of 0.5 mA/cm 2 (provided that a reaction current on the oxidizing side be positive) or more at a potential higher than 5. 7 V in an LSV measurement at a potential sweep rate of 1 mV/s using a glassy-carbon disk electrode as a working electrode, a platinum electrode as a counter electrode, and a lithium electrode as a reference electrode.