Lithium batteries that operate at high temperatures could be cheaper and safer than other metal batteries for electric cars.
Most of today’s electric cars use batteries that contain nickel and cobalt. However, these nickel-based batteries have the potential to overheat, which could pose a safety risk. In addition, they are expensive, while the cobalt they contain is difficult to obtain and toxic.
A cheaper and safer alternative called lithium iron phosphate (LFP) batteries might be a better option. LFP batteries generally perform poorly compared to nickel batteries, but Chao-Yang Wang and colleagues from Pennsylvania State University have shown that their performance improves when they are first heated.
The team heated the LFP batteries to 60 ° C and maintained this temperature. The batteries then performed better than two common types of nickel batteries, which operate at their normal and cooler operating temperatures. LFP batteries performed well at 60 ° C because they produce much less additional heat when discharged.
Read more: Best year ever for electric cars is a tipping point for green transport Electric car manufacturers prefer nickel batteries over LFP batteries because nickel batteries have a higher energy density, which means they can carry a vehicle farther when charged.
But Wang and his team have shown that while hot LFP batteries are often only partially charged – which can be done in just 10 minutes – it should be possible for cars with lithium batteries to travel long distances with relatively little. of embarrassment. This approach to charging can be safer than rarely but fully charging a nickel-based battery because charging them for a long time can heat them up to temperatures that could start a fire.
Even though heating LFP batteries requires energy, delivering them at a higher temperature provides performance benefits that outweigh the additional costs, the researchers suggest. In addition, because LFP batteries can safely operate at high temperatures, there is less need for battery cooling technology used with nickel batteries. It also reduces energy needs and should help reduce running costs.
“Lithium batteries will further reduce costs and quickly improve charging capacity and safety,” said Wang. His team is now working in partnership with Battery and Automakers to use these LFP batteries in electric vehicles.