Tailoring Alkyl Chain Length of linear ester in Moderately Concentrated Electrolyte for High-Performance Graphite Anode in K-Ion Batteries

Abstract

K+ desolvation in moderately concentrated ester electrolytes becomes easier with longer alkyl chain of linear ester. An electrolyte of 2.4 M KFSI in an ethylene carbonate+butyl methyl carbonate mixture renders the graphite anode a high capacity of 261 mAh g-1 and 93% capacity retention after 500 cycles at 2 C.