Lithium-Ion: Electrolyte

Electrolyte Development For Li-Rich High-Voltage Batteries Wang et al. proposed a novel approach to suppress both voltage decay and capacity fade in Li1.2Mn0.6Ni0.2O2 (LMR) cathodes by examining how different electrolyte solvents affect oxygen loss from the cathode surface. The study focused on the effect of EC on surface oxygen loss from the cathode. While EC solvent does not affect bulk oxygen SXRD and GITT, there is an increase in surface oxygen loss XAS, EELS, and Raman), which they further found to correlate with increased Ni and Mn dissolution (leakage current analysis and OEMS. Galvanostatic cycling test of LMR versus LTO cells showed that an electrolyte composed of only EMC solvent has 75% better capacity retention after 400 cycles when compared to an electrolyte containing both EC and EMC.

Using EC-free electrolytes (e.g. pure EMC) reduces surface oxygen loss and transition metal dissolution from the cathode, while minimizing capacity degradation and voltage fade for Li-rich high voltage batteries

Source: Wang, Rui, et al. "Influence of Carbonate Electrolyte Solvents on Voltage and Capacity Degradation in Li‐Rich Cathodes for Li‐ion Batteries." Advanced Energy Materials 2024 2401097.

Extracted from the PDF; charts and images may read imperfectly.