Recent progress on silicon-based anode materials for practical lithium-ion battery applications
Developing high-energy rechargeable lithium-ion batteries (LIBs) is vital to the substantial development of electric vehicles and portable electronic devices. The limited specific capacity of the state-of-the-art cathode and anode materials is the biggest obstacle to high-energy LIBs. With regard to anode materials, Si has been regarded as one of the most promising next-generation anodes due to its substantially higher capacity (~ 4200 mA h g−1for Li4.4Si) than traditional graphite anode (~ 372 mA h g−1), low operation potential, high abundance, and environmental friendliness. Several challenges need to be addressed, however, to make Si-based anodes commercially available, including such drawbacks as the tremendous volume variation during the discharge/charge process, unstable solid electrolyte interphase films, and poor electrical conductivity, which significantly restrict its practical application. In this review, we summarize the recent progress on Si-based anode materials from both the fundamental science point of view and the industrial perspective. From fundamental research to industrial application, the Si-based shell-containing nanostructures (core/shell and yolk/shell) and Si/graphite-based composites (Si/carbon and SiOx/carbon) are mainly covered to illustrate how these designs could solve the challenges of Si-based anodes. In addition, research progress on binders, electrolytes, and electrode additives towards enhanced electrochemical performance of Si-based anodes is also described. Finally, the remaining challenges and perspectives on the rational design of Si-based anode materials to realize commercialization are discussed and proposed.