As lithium ions are removed during the charging process, it forms a lithium-depleted iron phosphate (FP) zone, but in between there is a solid solution zone (SSZ, shown in dark blue-green) containing some randomly distributed lithium atoms, unlike the orderly array of lithium atoms in the original crystalline material (light blue).
Like any other battery, Lithium Iron Phosphate (LiFePO4) battery is made of power-generating electrochemical cells to power electrical devices. As shown in Figure 1, the LiFePO4 battery consists of an anode, cathode, separator, electrolyte, and positive and negative current collectors.
In LiFePO4 batteries, the iron and phosphate ions form grids that loosely trap the lithium ions as shown in Figure 2. During the charging of the cell, these loosely trapped lithium ions easily get pulled to the negative electrode through the membrane in the middle.
B. Mao, C. Liub, K. Yang, “Thermal runaway and fire behaviors of a 300 Ah lithium ion battery with LiFePO4 as cathode”, Renewable and Sustainable Energy Reviews, vol. 139, Apr 2021, 110717. Like any other battery, Lithium Iron Phosphate (LiFePO4) battery is made of power-generating electrochemical cells to power electrical devices.
While transferring the ion, the host matrix gets reduced or oxidized, which releases or captures an electron. Cathode Materials: The material used to make the cathode electrode is built as a source of lithium ions. Since a carbon electrode is used as the anode terminal in lithium battery, it does not contain any lithium.
During the charge, the released lithium ions travel from the positive terminal to negative terminal through the electrolyte. When the battery feeds an electric load i.e. during discharging, the lithium ions came back from the negative electrode to the positive electrode.