Patent ID: 7063916

Claim:
A battery comprising: a cathode comprising a cathode current collector, an external cathode region having an active material layer only on the external side of the cathode current collector, an exposed cathode region wherein no active material layer is provided, and a both sides cathode region having an active material layer on both sides of the cathode current collector; an anode comprising an anode current collector, an external anode region having an active material layer only on the external side of the anode current collector, an exposed anode region wherein no active material layer is provided, and a both sides anode region having an active material layer on both sides of the anode current collector; and an electrolyte comprising propylene carbonate, ethylene carbonate, a low viscosity solvent having a boiling point of 150° C. or less, a carbonic acid ester of an unsaturated compound and a lithium salt; and a content of the propylene carbonate is from 5 wt % to 20 wt %, and a content of the carbonic acid ester is from 0.3 wt % to 3 wt %.