Scientists at the University of Texas at Austin have begun research into cathodes for nickel-based batteries that could potentially increase the operating time of electric vehicles on a single charge.
Nickel has a number of advantages over traditional cobalt. Thanks to nickel's increased energy density, vehicles will be able to travel longer distances without recharging. However, due to its reputation as an unstable metal, nickel raises questions about safety, thermal stability and service life.
„High-nickel cathodes have the potential to revolutionize the electric vehicle market by providing longer range. "Our study provides a deep analysis of their thermal stability, which is essential for developing safer batteries," said Arumugam Manthiram, a professor in the Department of Mechanical Engineering.
The researchers performed more than 500 measurements on 15 high-nickel cathode materials. The scientists' key discovery was the identification of a critical charge level for each cathode material, which creates a safe operating limit.
Battery materials become unstable when they approach this critical charge level. If these instabilities are not controlled, they can lead to overheating. To mitigate this threat, the researchers have created a thermal stability rating.
This research is expected to help manufacturers improve battery designs while maintaining the high energy density benefits associated with nickel.
“Our work is a roadmap for the industry to follow, ensuring that the high energy density of these cathodes is not achieved at the expense of safety,“ the scientists said.