The use of Li metal anodes for secondary batteries is a major challenge in the academe. To address the issues associated with this, there is active research to obtain electrolytes for the effective use of Li metal anodes. Specifically, there is considerable attention on improving the oxidation stability and suppressing the dendrite formations of Li metal through the formation of a passivation film on cathode and anode surfaces. However, there is limited knowledge on the correlation between electrolyte molecules and formation of passivation films at a molecular level, which prevents the efficient development of highperformance electrolytes. In this work, we analyze reported experimental results on materials that contribute to the formation of cathode and anode films in widely used ether-based electrolytes through first-principles calculations. The oxidation and reduction energies are found to be insufficient in