| abstract |
(57) Abstract: An object of the present invention is to minimize or eliminate the first cycle irreversible capacity of a lithium ion battery and to maintain a low temperature cycle capacity of the battery. SOLUTION: The above problems are a) a negative electrode intercalating with an alkali metal, b) a positive electrode made of an electrode active material intercalating with an alkali metal, c) a non-electrode for activating a negative electrode and a positive electrode. An electrochemical cell comprising an aqueous electrolyte solution and d) a sulfate ester additive contained in the electrolyte solution, wherein the sulfate ester additive has a general formula R 1 OS (= O) 2 (OR 2 ), wherein a C (sp 2 or sp 3 ) —C (sp 3 ) linking unit having a C (sp 3 ) carbon is directly bonded to a —OSO 3 — functional group. The problem is solved by an electrochemical cell characterized by being selected from the group consisting of silyl sulfate, tin sulfate and organic sulfate having one unsaturated hydrocarbon. |