Hybrid ionic liquid–organic electrolyte technologies for sodium-ion batteries

An innovative ionic liquid–organic hybrid electrolyte technology was developed to obtain safer and more reliable sodium-ion battery (SIB) systems. The formulation is based on the 1-ethyl-3-methyl-imidazolium bis(flurosulfonyl)imide (EMIFSI) ionic liquid combined with the Diglyme cosolvent, which showed good performance in SIBs. The hybrid electrolyte formulation was qualified in terms of thermal and ion transport properties and electrochemical stability. The results, reported and discussed in the present manuscript, showed how it is feasible to improve conductivity without decreasing the safety and electrochemical stability of ionic liquid-based electrolytes.