Influence of Electrolyte on Lithium Cycling Efficiency with Pressurized Electrode Stack

The dependence of lithium cycling efficiency on stack pressure was studied for several electrolytes. To evaluate the cycling efficiency , we calculated the figure of merit of lithium as . The effect of solvents on the change with pressure was examined for solute electrolytes containing 2‐methyltetrahydrofuran (2MeTHF), ethylene carbonate (EC)/2MeTHF, propylene carbonate (PC), or EC/PC. The electrolyte showed the largest (80 at 125 kg/cm2). With the electrolytes and , was less dependent on stack pressure than it was with the electrolytes and EC/2MeTHF, probably because a different separator was used for the former electrolytes. Examining the effect of the solute on the change with pressure showed that the for reached maximum values at 50 and 75 kg/cm2, respectively, and that the values for increased with increasing stack pressure up to at least 125 kg/cm2.