Correlating Interfacial Structure and Dynamics to Performance in Lithium Metal Batteries
Richard May, Chemical Engineering, Marbella Group
Abstract: While the process of electrifying transportation is already underway, competing with fossil fuels in applications such as long-range
vehicles and aircrafts will require energy densities that are beyond what is achievable using conventional Li-ion battery chemistries. Li
metal batteries are promising candidates for such applications, yet meeting cycle life, power density, and safety demands while utilizing the unmatched specific capacity of Li metal anodes is a formidable challenge. It is well known that the interfacial layer of electrolyte decomposition products which forms on the Li surface during electrochemical cycling (i.e. the solid electrolyte interphase (SEI)) is critical in dictating Li deposit morphology and subsequent performance. However, both the composition and arrangement of the SEI are difficult to study because the SEI is just nanometers-thin, air-sensitive, and evolves as a function of electrochemical cycling protocol. Thus, it is important to develop in situ and operando techniques which are capable of characterizing the SEI in its native environment. Here, we study interphase formation in carbonate, ether, solid ceramic, and highly concentrated electrolytes to develop a framework for the general design of electrolytes and SEIs for Li metal batteries.