Silicon deposition in the pores of a microporous carbon enables stable high-performance silicon/carbon anodes

However, achieving a uniform distribution andhigh silicon loading while limiting severe volume expansionremains a critical challenge. We have shown that a carbonhost with a high microporosity has a strong confinement, enabling the fabrication of silicon/carbon composites with highsilicon loading.

More importantly, the microporosity isfound to govern both the silicon deposition behavior and theresulting electrochemical performance. A high microporecontent (92%) promotes preferential silane adsorption anddirects silicon nucleation within micropores, producing uniformly dispersed amorphous silicon domains with a highmass loading of 51%. The confinement mechanism simultaneously buffers volume expansion during lithiation and suppressesthe formation of the detrimental crystalline Li15Si4 phase.