Anionic Coordination Manipulation of Multilayer Solvation Structure Electrolyte for High-Rate and Low-Temperature Lithium Metal Battery

摘要

Challenges from high-energy-density storage applications have boostedthe pursuit of designing high-rate and low-temperature lithium (Li)metal batteries (LMBs). Formulating high-concentration electrolytes(HCEs) with a high transference number (t_+) is an alternative solutionto satisfy these demands. However, the implementation of HCEs isimpeded by their lower ionic conductivity, higher viscosity, poorer wettability,and higher melting point, which are harmful to the practicalapplications. Herein, an anionic coordination manipulation strategyis proposed to break the constraints presented by HCEs. By manipulatingthe anionic species with different coordinating abilities, a hight_+ up to 0.9 can be achieved even in the low-concentration electrolytesof 1 mol L~(?1). By further forming a multilayer solvation structure inthe anion manipulated electrolyte using non-polar diluents, high LiCoulombic efficiency superior to 99 can be maintained under a highcurrent density of 3 mA cm~(?2), and much-improved performance is alsodemonstrated in high-loading Li metal pouch cells. Furthermore, whenapplying multilayer solvated structure in electrolyte engineering, Limetal anodes at subzero temperature and LMBs at 0 ℃ also exhibitimpressive cycling stability. This work provides a new guideline fordesigning advanced electrolytes for high-rate LMBs under practicalconditions.