In the quest to increase energy density of lithium-ion cells, silicon-containing negative electrodes have been extensively investigated. The long-term performance of these electrodes is limited due to the instability of the electrode-electrolyte interface that is continually disrupted during the lithation-delithiation cycles. Therefore, the development of an electrolyte formulation that enhances the stability of the interface would be a significant step forward.

We conducted a comparative study of several fluorinated carbonates like methyl 3,3,3-trifluoroethyl carbonate, bis(3,3,3-trifluoroethyl) carbonate, 3,3,3-trifluoropropylene carbonate, and mixtures thereof as solvents for NCM523//Gr-Si CR2032 cell electrolyte formulations.

Comprehensive data from rate study, impedance and cycle life evaluation tests will be presented and discussed.