A new lithium-based electrolyte invented by Stanford University scientists could pave the way for the next generation of battery-powered electric vehicles (EVs). Their electrolyte design boosts the performance of lithium metal batteries, a promising technology for powering not only EVs but also laptops and other devices.
“Most electric cars run on lithium-ion batteries, which are rapidly approaching their theoretical limit on energy density,” said Yi Cui, professor of materials science and engineering and of photon science at the SLAC National Accelerator Laboratory. “Our study focused on lithium metal batteries, which are lighter than lithium-ion batteries and can potentially deliver more energy per unit weight and volume.”
Lithium-ion batteries, which are used in everything from smartphones to electric cars, have two electrodes – a positively charged cathode containing lithium and a negatively charged anode usually made of graphite. An electrolyte solution allows lithium ions to shuttle back and forth between the anode and the cathode when the battery is used and when it recharges.
A lithium metal battery can hold about twice as much electricity per kilogram as today’s conventional lithium-ion battery. Lithium metal batteries do this by replacing the graphite anode with lithium metal, which can store significantly more energy.