Enhancing the stability of high-voltage lithium-ion battery by using sulfur-containing electrolyte additives

摘要

The influences of two sulfur-containing electrolyte additives, prop-1-ene-1,3-sultone (PES) and 1,4-butane sultone (BS) on the cyclic stabilities of LiNi1/3Co1/3Mn1/3O2 (NMC111) cathode and graphite anode were evaluated. With the addition of 2wt.% PES and 3vol.% BS into NMC111/Li half-cell, the capacity retention was significantly increased from 69% to 85.1% and 86.9% respectively after 80 charge-discharge cycles in 3V-4.6V vs. Li/Li+. The related factors were investigated via theoretical calculation and experimental characterization. Results indicated that the improved cycling stability on high working voltage could be ascribed to the participation of PES and BS in the formation of a smooth film on the NMC111 surface, which effectively suppressed the subsequent decomposition of base electrolyte and further structure degradation of NMC111. Meanwhile, according tothe charge-discharge test on the graphite/Li, PES-containing and BS-containing cells showed stable cycle efficiency on graphite anode for 50 cycles.