Elevated Electrochemical Performance of LiNi0.1Mg0.1Co0.8O2 and LiFePO4 Cathodes with Tris(2,2,2-trifluoroethyl) Phosphite as an Efficient Electrolyte Additive

The significant role of Tris(2,2,2-trifluoroethyl) phosphite (TTFP) as an efficient additive during cycling of the layered nanostructured LiNi 0.1 Mg 0.1 Co 0.8 O 2 and olivine LiFePO 4 cathode materials in EC/DMC and 1M LiPF 6 electrolyte for Li-ion battery are extensively investigated in this work. The electrochemical characterization techniques such as cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy show that TTFP improves cycling stability and reduces the irreversible capacity of LiNi 0.1 Mg 0.1 Co 0.8 O 2 and LiFePO 4 electrodes. Also, the presence of TTFP in electrolyte solution reduces the impedance in LiNi 0.1 Mg 0.1 Co 0.8 O 2 and LiFePO 4 cathode materials at room temperature. A family of Nyquist plots was obtained from LiNi 0.1 Mg 0.1 Co 0.8 O 2 and LiFePO 4 electrodes for various potentials during the course of charging. The addition of TTFP in the electrolyte reduces the surface impedance of lithiated LiNi 0.1 Mg 0.1 Co 0.8 O 2 and LiFePO 4 which can be attributed to the reaction of the additive on the electrode’s surface. Also, the presence of the additive TTFP in LiNi 0.1 Mg 0.1 Co 0.8 O 2 and LiFePO 4 cell enhances the lithium diffusion rate and improves the electronic conductivity of the cathode material.