Patent ID: 7608364

Claim:
A lithium ion secondary battery comprising a cathode, an anode, a nonaqueous electrolytic solution, and a laminate film casing, wherein the anode comprises a non-graphitizable carbon which is amorphous as an anode activator; and the nonaqueous electrolytic solution consists of a nonaqueous solvent, an electrolyte, and an anode protecting component consisting of at least one sultone having a 5- to 7-membered cyclic sulfonate structure represented by general formula (1): wherein R 1 , R 2 , R 3 , R 4 , R 5 and R 6 independently represent a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms or an aryl group; and n represents an integer of 0 to 2, and at least one vinylene carbonate represented by general formula (2): wherein R 1 and R 2 independently represent a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms or an aryl group, wherein the non-aqueous solvent is selected from the group consisting of propylene carbonate, ethylene carbonate, butyrene carbonate, vinylene carbonate, linear carbonates, aliphatic carboxylates, γ-lactones, linear ethers, cyclic ethers, dimethyl sulfoxide, 1,3-dioxolane, formamide, acetamide, dimethylformamide, acetonitrile, propionitrile, nitromethane, ethyl monoglyme, phosphoric acid triesters, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, 3-methyl-2-oxazolidinone, propylene carbonate derivatives, tetrahydrofuran derivatives, ethyl ether, anisole, N-methylpyrrolidone and fluorocarboxylates.