Lithium iron phosphate battery is actually a lithium ion battery with lithium iron phosphate as the positive electrode material, and for lithium ion battery, the positive electrode material is divided into various kinds such as lithium cobaltate, lithium manganate, lithium nickelate, ternary material, iron phosphate. Lithium, etc., among which lithium iron phosphate is the most commonly used material in the lithium battery industry.
The lithium iron phosphate battery is connected by an aluminum foil to the positive electrode of the battery, and the left side is a polymer diaphragm which separates the positive electrode from the negative electrode, but the lithium ion Li can pass and the electron e- cannot pass, and the right side is the negative electrode of the battery composed of carbon, and the copper foil Connected to the negative pole of the battery, between the upper and lower ends of the battery is the electrolyte of the battery, the battery is sealed by a metal casing, and the LiFePO4 battery is charged, the lithium ion Li in the positive electrode migrates to the negative electrode through the polymer membrane; during the discharge, the negative electrode The lithium ion Li migrates to the positive electrode through the separator, and the lithium ion battery is named after the lithium ion migrates back and forth during charge and discharge.
Lithium-ion battery working principle. When the battery is charged, Li migrates from the 010 surface of the lithium iron phosphate crystal to the surface of the crystal. Under the action of the electric field force, the electrolyte enters the electrolyte, passes through the separator, and then migrates to the surface of the graphite crystal through the electrolyte. Then embedded in the graphite lattice, after lithium ions are deintercalated from lithium iron phosphate, lithium iron phosphate is converted into iron phosphate; when the battery is discharged, Li is deintercalated from the graphite crystal, enters the electrolyte, passes through the separator, and then passes through the electrolyte. The surface is transferred to the surface of the lithium iron phosphate crystal, and then re-inserted into the crystal lattice of lithium iron phosphate via the 010 surface, and then discharged to the lithium iron phosphate positive electrode through the electric conductor to start discharging.
For the conduction of the positive and negative electrodes of lithium iron phosphate battery, it is necessary to add a conductive agent to the positive and negative electrodes of the battery to form it in the active material of the battery. In the actual design process and in the actual production process, how to achieve the above three An equation is also needed to design a series of experiments to verify, build mathematical models or build empirical formulas, and then use these models or formulas to design lithium-ion batteries.
At present, the domestic lithium-ion battery technology is mature and has reached the world's leading level . The current industry is still paying attention to lithium-ion batteries with lithium iron phosphate as the positive electrode, and many countries have developed new lithium-ion battery materials, but currently There is no large-scale production, some experts pointed out that carbon phosphate lithium cathode materials are the mainstream industry at least within 10 years.
