Range anxiety, expense, safety, weight – just some of the issues potential electric car buyers are having to face. Lithium-ion batteries have been around for some time and have been the basis for electric vehicle development over the past decade, but maybe that is about to change.
Ford, Toyota, Daimler, Volkswagen, Renault, Nissan, Mitsubishi and Hyundai are investing hundreds of millions of dollars in solid-state battery research and development. This emerging technology could open the way to giving electric vehicles between 500 – 1,000 miles range on a single charge; all from a battery that is appreciatively less bulky than the current lithium-ion battery. They would also eliminate the flammability issues that are inherent in lithium-ion batteries.
Less weight, greater range and safer – too good to be true?
Currently, a lithium-ion battery has solid lithium electrodes encased in a liquid chemical electrolyte, whereas, a solid-state battery has solid lithium electrodes set in rigid conductive material such as ceramic or a polymer.
Getting rid of the liquid electrolyte should make the solid-state battery cheaper to make, longer lasting and fireproof. They would also not require liquid cooling and therefore reduce the overall weight of the vehicle.
The biggest benefit, theoretically, of solid-state technology, is the improved “energy density” which is the amount of charge it can hold, relative to its weight and volume.
However, the biggest problem still to be overcome is getting electron ions to flow freely through the solid electrolyte, though recent developments are looking promising with Toyota hoping to showcase the new technology at the 2020 Summer Olympics in Tokyo. Full implementation may not happen before the end of the next decade, but in the meantime, energy density is being addressed in lithium-ion batteries with the addition of silicon, which may prove a viable interim solution.
Mark Salisbury, Editor, FleetPoint
