Research Progress on SiC Composite Materials, Electrolyte Additives and Binders of Negative Electrodes

With the increasing demand for mileage and lifespan in the E-vehicles, it is imperative to develop a new generation of SiC materials for high-capacity Li-ion batteries, which has also been a very hot research subject both domestically and internationally during the past two decades. This article focuses on the latest progress on SiC composite structures, electrolyte additives and novel binders. By designing SiC composites with different structures, problems such as large volume expansion, poor conductivity, and unstable SEI film of Si-based electrodes can be alleviated effectively. Among them, porous Si/carbon/graphite composites are considered a promising composite structure due to the advantages of rich pore channels, effective release of enormous stress caused by Si volume changes, as well as the shortened distance for lithium ions transport. However, it is a highly challenging task how to reduce the synthesis cost of nano porous silicon and its Si/C/G composites that needs to be focused on in the future. The other two important factors that affect the electrochemical performance of SiC materials are of electrolyte additives and binders. Agreeing to use two or more different additives can more effectively achieve synergistic effects to compensate for the shortcomings of one additive; It is a very interesting self-healing adhesive/binder that can solve the problems of material cracks and structural damage caused by volume changes in SiC electrodes, which can significantly improve the cycling stability and rate capability. This article provides a concise summary of their latest research results in recent years, and prospects for future research trends in the application of Si-based materials in the Li-ion batteries.