Lithium batteries are secondary battery systems that use two different lithium-intercalating compounds that can reversibly insert and extract lithium ions as the positive and negative electrodes of the battery. During charging, lithium ions are extracted from the crystal lattice of the positive electrode material and inserted into the crystal lattice of the negative electrode material after passing through the electrolyte, making the negative electrode rich in lithium and the positive electrode poor in lithium; during discharge, lithium ions are extracted from the crystal lattice of the negative electrode material and pass through The electrolyte is then inserted into the crystal lattice of the positive electrode material, making the positive electrode rich in lithium and the negative electrode poor in lithium. In this way, the difference in potential between the positive and negative electrode materials relative to metallic lithium when inserting and extracting lithium ions is the operating voltage of the battery.
