Triphenyl Borate as an Effective Film-Modification Additive for Regulating the Solid Electrolyte Interphase Formed on Graphite and Silicon Based Anode

Abstract

Triphenyl borate (TPB) was attempted to introduce into lithium-ion batteries (LIBs) as a novel electrolyte additive. The effects of the additive on the electrolyte properties and electrochemical performances of a conventional artificial graphite (AG) and a commercial silicon-carbon (SiC) anode were investigated. It is found that the moderate addition of TPB remarkably increases the reversible capacity and coulombic efficiency, as well as improves the cycle and rate capability of the two anodes. The CV, SEM and XPS combined with DFT calculation reveal that the TPB can be preferentially reduced on the anode to generate B-rich solid electrolyte interphase (SEI) with low interface resistance, which effectively passivates the anode to mitigate the parasitic reaction.

Keywords: Triphenyl borate, Electrolyte additive, Solid electrolyte interphase, Lithium Ion Battery