Discovery Files

Researchers develop promising approach to smaller, more powerful, safer electric vehicle batteries

Finding is a step on the way to solid-state batteries

Two factors dominate the development of batteries for electric vehicles: power, which determines the vehicle range; and cost, critical in the competition with internal combustion engines. The targets set by the U.S. Department of Energy to accelerate the transition from gasoline-powered vehicles to electric vehicles cannot be achieved with conventional lithium-ion batteries because of their limited storage capacity and relatively high production cost.

A promising approach to making smaller, lighter, more powerful and safer batteries is to use solid-state cells with anodes made of metallic lithium instead of graphite. A research team led by Jennifer Rupp at the Massachusetts Institute of Technology and the Technical University of Munich has developed such a new synthetic process. The process is based not on a ceramic precursor compound but on a liquid one. Results of the research are published in the journal Angewandte Chemie.

The characterization of the lithium oxide crystallization process was supported by the U.S. National Science Foundation through the National Nanotechnology Coordinated Infrastructure Network.

A lithium ceramic could act as a solid electrolyte in a more powerful and cost-efficient generation of rechargeable lithium-ion batteries. In contrast to conventional lithium-ion batteries, which have liquid organic electrolytes and use a polymer film, all components of a solid-state battery are solids. A thin ceramic layer simultaneously functions as a solid electrolyte and separator. It is effective, the researchers say, against both the dangerous short circuits caused by the growth of lithium dendrites and thermal runaway.  In addition, it contains no easily ignited liquids.