In general, a battery is a collection of galvanic cells. A lithium-ion (Li-ion) battery is a rechargeable battery that is widely used in small electronics and, increasingly, in hybrid and electric vehicles. Both the anode and cathode contain lithium atoms in the Li-ion battery. The anode is typically lithium cobalt (LiCoO₂) in handheld electronics or lithium nickel manganese cobalt oxide (LiNiMnCoO₂or NMC) in electric vehicles.

而发电,oxidati的结果on reaction at the anode are positively charged lithium ions and negatively charged electrons. At the cathode, the lithium cations gain electrons to form a lithium compound with a neutral charge. During charging these reactions take place in the opposite direction and electrons move from the negative anode to the positive cathode, storing electrical energy as chemical energy in the cell.

Figure 1:Lithium battery: the electrolytes are separated by a separator. The reaction can be reversed, which allows the battery to be charged.