Measuring the most important figure of merit in a lithium metal battery

Work on solid electrolytes for rechargeable lithium-based batteries is motivated by the potential benefits of lithium-metal anodes for a variety of applications, including electric vehicles. Dendrite formation has been the key challenge preventing commercialization of rechargeable lithium-metal batteries, so establishing, validating, and improving the dendrite resistance of electrolytes is a key enabler of progress in the field. Typical symmetric cycling tests of Li-Li cells introduce operational and theoretical limitations which compromise the data produced and the conclusions which can be drawn from such testing. A high-throughput technique for unidirectional critical current density testing is presented which has allowed the development of a solid electrolyte capable of withstanding current densities of at least 300 mA cm - 2. The theoretical and empirical basis for this testing methodology is outlined, results are presented and analyzed, and best practices for critical current density testing of solid electrolyte materials are proposed.

Speaker: Tim Holne, QuantumScape