US Patent 7476469 Lithium secondary battery

A rechargeable lithium battery including a positive electrode, a negative electrode and a nonaqueous electrolyte, said positive or negative electrode being an electrode which has, on a current collector, a thin film of active material that stores and releases lithium, the thin film of active material being divided into columns by gaps formed therein in a manner to extend in its thickness direction, and the columnar portions being at their bottoms adhered to the current collector, the rechargeable lithium battery being characterized in that the nonaqueous electrolyte includes a mixed solvent consisting of two or more different solvents and containing at least ethylene carbonate and/or vinylene carbonate as its constituent.