Micro-sized CVD-derived Si–C anodes: challenges, strategies, and prospects for next-generation high-energy lithium-ion batteries

Abstract

The development of high-capacity anodes is of paramount importance to address the rapidly increasing demand for high-energy-density lithium-ion batteries (LIBs). While the commercialization of nanoscale silicon (Si) and microscale silicon monoxide (SiO) anodes represents a significant milestone, their widespread adoption remains constrained by challenges such as high production costs, severe interfacial side reactions, and substantial initial capacity losses. Recently, a new class of micro-sized Si–C anodes has emerged, fabricated via the co-pyrolysis of silane and gaseous hydrocarbons into porous carbon scaffolds using chemical vapor deposition (CVD). These anodes demonstrate promising performance and improved economic viability. However, the unclear mechanisms governing their structural and interfacial evolution pose significant barriers to their practical application. In this perspective, we critically summarize recent advances in understanding the intrinsic phase transition properties and the dynamic evolution of the solid–electrolyte interphase (SEI), with particular emphasis on the “breathing” effect of the SEI during cycling that leads to failure. From both dynamic and static perspectives, we highlight various strategies to address these challenges, especially under demanding conditions such as fast charging and extreme temperatures (high and low). By providing a comprehensive framework for addressing these issues, this perspective aims to offer valuable insights into enhancing the overall performance of this emerging class of anodes and accelerating their industrial adoption.