Patent ID: 7993783

Claim:
A non-aqueous electrolyte secondary battery comprising: a positive electrode containing a positive electrode active material; a negative electrode containing a negative electrode active material other than metallic lithium; and a non-aqueous electrolyte, wherein: the positive electrode active material contains a lithium cobalt oxide as its main component and having a potential of 4.4 to 4.5 V (vs. Li/Li + ); the non-aqueous electrolyte contains 0.1 to 10 volume % of compound having an ether group; and the battery is charged until the potential of the positive electrode reaches 4.4 to 4.5 V (vs. Li/Li + ), wherein the compound having an ether group is at least one compound selected from the group consisting of diethyl ether, 2-methyltetrahydrofuran, tetrahydrofuran, diethylene glycol dimethyl ether, 1,4-dioxane, 12-crown-4-ether, and 15-crown-5-ether.