Design and synthesis of battery electrolyte additives with dioxolone derivatives for lithium-ion batteries

Abstract

Vinylene carbonate (VC) derivatives are very significant structure in the field of electrolyte additives for Li-ion battery. VC derivatives could form a stable SEI, which could prevent electrolyte degradation by blocking the electron transport while allowing lithium ions to pass during cycling. Electrolyte additives are the most economical and efficient method to solve theses problems and thus improve lithium ion battery performance. However, current conventional solid electrolyte interphase additives, such as vinylene carbonate and fluoroethylene carbonate, have limitations of abilities of achieving a long lifespan and fast chargeability in lithium-ion batteries (LIBs) for simultaneously. Here we reported a next-generation synthetic additive with dioxolonee. In terms of syntesis, O-trifluoromethylation has been a challenging task in organic synthesis. We installed CF3 and TMS group to alcohol via the modified method from the precedent protocols appropriately. The retrosynthetically designed solid electrolyte interphase-forming additives, 5-methyl-4-((trifluoromethoxy)methyl)-1,3-dioxol-2-one and 5-methyl-4-((trimethylsilyloxy)methyl)-1,3-dioxol-2-one can form highly stable interface. The interface architecture from the synthesized vinylene carbonate-type additive enables high-energy-density LIBs with 81.5% capacity retention after 400 cycles at 1 C and fast charging capability (1.9% capacity fading after 100 cycles at 3 C).