US Patent 7563541 Lithium-ion battery

A battery includes a positive electrode including a current collector and a first active material and a negative electrode including a current collector, a second active material, and a third active material. The first active material, second active material, and third active material are configured to allow doping and undoping of lithium ions. The third active material exhibits charging and discharging capacity below a corrosion potential of the current collector of the negative electrode and above a decomposition potential of the first active material.