A novel MEMP-DFOB electrolyte additive to improve low-high temperature performances of SiO/Gr anode based pouch full cells

How to improve interface stabilization of silicon/silicon oxide anodes during the lithiation and delithiation process is a big challenge to promote their commercial utilization. In this work, a novel electrolyte additive of mesylethyl-methyl-pyrrolidinium (MEMP-DFOB) is reported, which helps to generate a beneficial film on the surface of silicon oxide-graphite (SiO/Gr) anode. Differential capacity vs. voltage (dQ/dV) results show that the film is formed at ~1.4 V. As a result, SiO/Gr anode based pouch full cells not only demonstrate enhanced discharge performance and cycling stability at −20 °C, but effectively inhibit gas releasing at high temperature of 45 and 60 °C, and successfully run over 900 cycles with a capacity retention of ~75 % at 45 °C. This strategy highlights a new way to develop SiO/Gr anode based lithium-ion batteries with outstanding performances at low and high temperature.