The charge-discharge reaction of lithium iron phosphate battery is carried out between the two phases of LiFePO4 and FePO4. During the charging process, LiFePO4 gradually separates from the lithium ions to form FePO4, and during the discharge process, lithium ions are inserted into FePO4 to form LiFePO4.
When the battery is charged, lithium ions migrate from the lithium iron phosphate crystal to the surface of the crystal, under the action of the electric field force, enter the electrolyte, then pass through the diaphragm, and then migrate to the surface of the graphite crystal through the electrolyte, and then are embedded in the graphite crystal lattice.
At the same time, electrons flow through the conductor to the aluminum foil collector of the positive electrode, flow through the tab, battery positive pole, external circuit, negative pole, and negative pole to the copper foil collector of the battery negative pole, and then flow to the graphite negative pole through the conductor. To balance the negative electrode charge. After the lithium ions are deintercalated from the lithium iron phosphate, the lithium iron phosphate is converted into iron phosphate.
When the battery is discharged, lithium ions are deintercalated from the graphite crystals, enter the electrolyte, and then pass through the diaphragm, migrate to the surface of the lithium iron phosphate crystal through the electrolyte, and then re-embed in the lithium iron phosphate lattice.
At the same time, electrons flow through the conductor to the copper foil collector of the negative electrode, through the tab, battery negative pole, external circuit, positive pole, and positive pole to the aluminum foil collector of the battery positive pole, and then flow to the iron phosphate through the conductor. Lithium positive electrode balances the charge of the positive electrode. After lithium ions are inserted into the iron phosphate crystal, the iron phosphate is converted into lithium iron phosphate.
