4.1 Electrolyte preparation
Commercially available electrolyte containing 1M LiPF6in a mixture of ethylene carbonate (EC), diethyl carbonate (DEC), and dimethyl carbonate (DMC) (1:1:1, by volume ratio) was used as the standard electrolytes. 2 wt % LiAsF6 (99.9%) and 2 wt % fluoroethylene carbonate (FEC) (99%) were added and gently stirred for 24 h to prepare the optimized electrolytes. All the materials are purchased from Sigma-Aldrich.