Improving Li Ion Storage Capability of V₂O₅ Electrode by Using Aminoalkyldisiloxane Electrolyte Additive

Abstract

The unstable electrolyte interphase layer on the surface of V 2 O 5 limits its Li + storage capability. Herein, a novel aminoakyldisiloxane compound, (3-(N,N-dimethylamino)diethoxypropyl) pentamethyldisiloxane (DSON), is applied as an efficient electrolyte additive for enhancing the electrochemical performance of V 2 O 5 electrode. DSON additive in the conventional carbonate-based electrolyte can inhibit the generation of acidic species by suppressing the hydrolysis of LiPF 6 . Additionally, DSON can also induce the formation of solid electrolyte interphase on the surface of V 2 O 5 electrode upon (de)lithiation, which decreases the charge transfer resistance of Li + at the interface between electrode and electrolyte. Thus, the V 2 O 5 electrode with the electrolyte containing DSON additive (0.5 wt %) delivers a higher specific capacity (311.8 mAh g-1 at 0.1 C), excellent cycling performance (248.1 mAh g À 1 at 0.5 C after 250 cycles) and rate performance (235.9 mAh g À 1 at 2 C). This work demonstrates that aminoakyldisiloxane is an effective electrolyte additive to stabilize the surface electrolyte film and improve the Li + storage capability of metallic oxide-based electrode materials.