Solid-state batteries use solid electrodes and solid electrolytes instead of liquid or polymer-gel electrolytefound in Lithium-ion batteries. It is claimed that solid-state batteries have greater energy density which means more enrgy can be extracted from a smaller and lighter battery. Solid state batteries also have better thermal management and hence they can lessen the risk of fire. QuantumScape has agreed to merge with Kensington Capital Acquisition Corp. to raise the capital it needs to commercialize these batteries for EVs. Link to the news: https://techcrunch.com/2020/09/03/vw-backed-quantumscape/