The material composition of lithium iron phosphate batteries can be analyzed in detail from the following aspects:
1. Cathode material: lithium iron phosphate (LiFePO₄/LFP)
Chemical properties: Olivine crystal structure, composed of four elements: iron, phosphorus, oxygen and lithium, chemical formula LiFePO₄, molecular weight 157.757, density 3.6 g/cm³. Its structural stability is high and its safety is better than traditional materials such as lithium cobalt oxide.
Raw materials and synthesis: Mainly generated by the reaction of lithium carbonate (Li₂CO₃) and iron phosphate (FePO₄), 1 ton of lithium iron phosphate requires 0.25 tons of lithium carbonate and 0.96 tons of iron phosphate. Synthesis methods include high-temperature solid phase method or liquid phase method.
Cost ratio: The cathode material accounts for a significant part of the battery cost and is greatly affected by the price fluctuations of lithium carbonate (for example, the unit price of lithium iron phosphate in 2023 is 88,000 yuan/ton).
2. Negative electrode material
Mainly artificial graphite or natural graphite, 1GWh battery requires about 176.8 tons of negative electrode material. Artificial graphite is more suitable for power batteries due to its low cost.
3. Electrolyte
Composed of lithium hexafluorophosphate (LiPF₆) and organic solvents, 1GWh battery requires about 1,400 tons of electrolyte, corresponding to 43.75 tons of lithium carbonate.
4. Separator
Used to separate the positive and negative electrodes and allow ions to pass through, 1GWh battery requires 16 million square meters of separator.
5. Current collector
The negative electrode uses copper foil (usually 4.5-8 microns thick), 1GWh battery requires 450-800 tons of copper foil.
