Electrolyte additives enable fast charging and stable cycling of LiNi0.8Co0.1Mn0.1O2 batteries

High energy density and fast charging are essential for lithium-ion batteries to replace petrol-powered vehicles. In this study, when LiDFOB, TMSPi, and FEC work together synergistically, they form a uniform, stable, and ultra-thin (2.859 nm) CEI film with low impedance (1.623 Omega after 150 cycles) on the NCM811 cathode. This film prevents the pulverization and microcracking of NCM811 particles during high-speed charging, thereby maintaining conductivity among the particles, inhibiting side reactions and decomposition of the electrolyte, and reducing impedance. Consequently, this results in enhanced cycling stability and rate performance for the battery. A discharge capacity of 139.04 mAh g- 1 can be achieved at 10 C charging rate with 77.4 % retention compared to 0.5 C. Following 375 cycles at 1 C/1 C, the LFTI electrolyte-based battery exhibits a specific capacity of 154 mAh g-1, retaining 90.4 % of its initial capacity. After 159 cycles at 5 C/0.5 C, reversible capacity reached 137.8 mAh g-1, retaining 83 %. The batteries also showed high-temp stability, maintaining 162.4 mAh g- 1 after 100 cycles at 45 degrees C, with 91.08 % retention. This research offers a promising strategy for electrolyte design for high-energy, fast-charging batteries.