Next Generation of Materials for Lithium-Ion Battery Anodes, Cathodes, Separators & Electrolytes

Abstract

Energy density and cost of conventional Li-ion batteries (LIBs) are closely approaching their limits. The reliance of conventional cathodes on the use of toxic metals additionally endangers health and safety of miners in developing countries. Novel materials for conversion-type cathodes and alloying-type anodes offer an opportunity to double energy stored in LIBs, reduce their cost by the same factor, and improve cell safety. Conventional separators suffer from poor thermal stability, limited mechanical strength in tension and compression, relatively large minimum thickness of 6 micron (typically 10-25 micron for safer versions used in electric vehicle (EV) LIBs) and relatively high ionic resistance, undesired for ultra-fast charging. Ceramic and ceramic-composite nanofiber-based separators enable one to overcome the current limitations and produce safer LIBs with higher energy density and faster charging abilities. Finally, conventional organic electrolytes suffer from flammability, limited electrochemical stability in contact with anodes and cathodes of high-energy LIBs and undesired chemical and electrochemical reactions with cathode materials that accelerate LIB fading, particularly at elevated temperatures. Several classes of solid electrolytes may offer effective solutions to overcome such drawbacks. In this invited talk I will provide an overview of the activities of our group in these complementary fields and share my understanding of the industrial requirements for the technology adoption and successful commercialization.