As the auto industry scrambles to produce more affordable electric vehicles, whose most expensive components are batteries, lithium iron phosphate (LiFePO4) is gaining traction as the battery material of choice. The chemical compound, LiFePo4, is a critical ingredient in next-generation batteries that offer higher energy density and thermal stability.
LiFePO4 is the latest in a long line of lithium-ion rechargeable batteries that have gained popularity thanks to their safety, longevity, and durability. These batteries are typically used in medical devices, backup power systems, and mobile solar generators. They don’t require corrosive lithium cobalt, which has been a source of concern for consumers concerned about harmful environmental effects and the dangers of improper disposal after batteries expire.
In addition to environmental concerns, the price of nickel and cobalt has skyrocketed in recent years due to political instability in the Democratic Republic of Congo (DRC) and conflicts with Russia over Ukraine, causing supply shortages for critical metals used in the production of EV cathode materials such as lithium nickel manganese cobalt oxide (NMC) and nickel cobalt aluminum oxide (NCA). The high cost of these metals is driving up EVs’ sticker prices, which could discourage adoption.
LFP is produced by reacting iron sulfate with phosphoric acid in a ceramic crucible, then mixing the resulting solid mixture with lithium carbonate and a carbon source to form a conductive coating. This mixture is then sent into a kiln that heats it to 700-800 degC to transform the amorphous LFP into olivine, which functions as a cathode. Most LFP factories are located in China. However, some Western companies, such as A123 before its bankruptcy and Denis Geoffroy’s company Nano One Materials, are working to build factories in the US. ICL, a producer of industrial phosphates, is now supplying phosphate raw materials to LFP firms in China.
These batteries can deliver a much longer lifetime than other lithium-ion batteries. This is partly because of the low self-discharge rate, meaning they will hold their charge for a long time when unused. In comparison, NMC and NiCad batteries can lose up to 20% of their monthly capacity when sitting unused.
Another advantage of LFP is its ability to handle a more comprehensive temperature range than other battery chemistries, making it more versatile and suitable for use in different climates. For example, the colder temperatures found in northern regions of the US can cause NMC and NCA batteries to lose their functionality.
However, the stability of LFP and higher energy density make it a more viable alternative to these other battery technologies for EVs operating in the north. This is why some manufacturers are experimenting with LFP batteries in their prototypes of upcoming vehicles, including Tesla. This is a promising development for the future of electric vehicle technology. It may be some time before we see LFP batteries appear on the roads, but it’s clear that they are poised to become more prevalent shortly.