Tri(ethylene glycol)-substituted trimethylsilane/lithium bis(oxalate)borate electrolyte for LiMn2O4/graphite system

Silane-based electrolyte is a promising candidate for safer electrochemical energy storage devices because it is thermally and electrochemical stable, less flammable and environmental benign. In this paper, electrochemical properties of one of the silane-based electrolytes, tri(ethylene glycol)-substituted trimethylsilane (1NM3)-lithium bis(oxalate)borate (LiBOB) was studied using LiMn₂O₄ as cathode and MAG graphite as anode. When combined with LiBOB as lithium salt, the 1NM3-LiBOB electrolyte can provide solid electrolyte interface (SEI) formation due to the reductive decomposition of LiBOB at first charging cycle. Compared to the electrolyte used in the conventional lithium-ion batteries, 1NM3-LiBOB electrolyte showed compatible battery performance in LiMn₂O₄/MAG chemistry. The AC impedance measurement indicates that the activation energy (E_a) obtained from the charge transfer impedance for 1NM3-LiBOB was higher than that of the state-of-the-art electrolyte. Due to its low conductivity, the rate capability of 1NM3-LiBOB electrolyte needs to be improved.