Non-aqueous electrolyte for electrochemical energy storage device and electrochemical energy storage device using the same

摘要

By using (a) a lithium salt, (b) a quaternary ammonium salt having a quaternary ammonium cation having three or more methyl groups, and (c) a nonaqueous electrolyte containing a nonaqueous solvent, Even if the quaternary ammonium salt is dissolved in the water electrolyte, lithium ion is stably occluded / released to / from the negative electrode material having a graphite structure, a high charge voltage can be set, and the charge / discharge cycle is repeated. Even so, an electrochemical energy storage device with small capacity degradation can be obtained.