A lithium battery is a type of rechargeable battery that uses the reversible reduction of lithium ions to store energy. The negative electrode of a conventional lithium-ion cell is typically graphite, a form of carbon. Lithium batteries are primary batteries that have metallic lithium as an anode. They are also referred to as lithium-metal batteries and stand apart from other batteries in their high charge density and high cost per unit.The term “lithium battery” refers to a family of batteries with different chemistries, comprising many types of cathodes and electrolytes.