The electrochemical window (EW) of electrolytes is considered
the
essential bottleneck of the voltage range for lithium batteries, which
is theoretically overestimated previously. In this work, we present
an innovative strategy to quantify the EW without experiential parameters
accurately. This strategy encompasses energy states and statistical
distribution from both thermodynamic and oxidized kinetic aspects.
Verified by linear sweep voltammetry, which specializes in intrinsic
redox kinetics of reactants and excludes the influences of products,
the most restrictive factor among the effects of condensation, thermal
motion, solvent, electric field, and catalysis determines the practical
EW. For polyethylene oxide (PEO) and ethylene carbonate (EC)-dimethyl
carbonate (DMC) with glassy carbon, the solvent effect is the restriction,
while for EC-DMC with LixCoO2, the catalysis effect of the LixCoO2 surface is the restriction. This work provides an effective
criterion for accurate prediction, guiding the electrolyte system
design to satisfy the expected EW