The charging and discharging reaction of lithium iron phosphate battery is carried out between LiFePO4 and FePO4. In the charging process, LiFePO4 gradually detach from lithium ions to form FePO4, and in the discharge process, lithium ions are embedded in FePO4 to form LiFePO4.

When a battery is charged, lithium ions migrate from the lithium iron phosphate crystal to the surface of the crystal. Under the force of an electric field, they enter the electrolyte, cross the diaphragm, and migrate through the electrolyte to the surface of the graphite crystal, where they are embedded in the graphite lattice.

At the same time, the electrons flow to the aluminum foil collector of the positive electrode through the conductor, the positive electrode of the battery, the external circuit, the negative pole, and the negative pole to the copper foil of the negative electrode of the battery, and then flow to the graphite negative electrode through the conductor, so that the charge of the negative electrode reaches balance. When lithium ions are removed from lithium iron phosphate, lithium iron phosphate is converted to iron phosphate.

When the battery is discharged, the lithium ions are removed from the graphite crystal, enter the electrolyte, and then cross the diaphragm, migrate through the electrolyte to the surface of the lithium iron phosphate crystal, and then reembed into the lattice of the lithium iron phosphate.

At the same time, electrons flow to the copper foil collector of the negative electrode through the conductive body, the anode ear, the battery negative pole, the external circuit, the positive pole, and the positive pole ear to the aluminum foil of the positive electrode of the battery, and then flow to the lithium iron phosphate positive electrode through the conductive body, so that the charge of the positive electrode reaches balance. When lithium ions are embedded in iron phosphate crystals, iron phosphate is converted to lithium iron phosphate.