Plasma-enhanced vacancy engineering for sustainable high-performance recycled silicon in lithium-ion batteries
Dingyi Zhang, Hong Gao, Jiayi Li, Yiwen Sun, Zeshen Deng, Xinyao Yuan, Congcong Li, Tianxiao Chen, Xiaoyu Peng, Chao Wang, Yi Xu, Lichun Yang, Xin Guo, Yufei Zhao, Peng Huang, Yong Wang, Guoxiu Wang, Hao Liu
Abstract
• Innovative Plasma-Assisted Vacancy Engineering: Introduction of controlled vacancy defects in recycled photovoltaic (PV) silicon through dielectric barrier discharge plasma-assisted milling (DBDP) combined with bismuth (Bi) modification, enhancing ion transport and mitigating internal stress. • Enhanced Structural Stability and Performance: The incorporation of Bi further stabilizes the anode by absorbing mechanical stress and facilitating lithium-ion accommodation at vacancy sites, leading to exceptional cycling stability and high-rate performance. • Sustainable and Scalable Approach: The use of recycled PV silicon not only addresses the challenges of silicon anodes but also contributes to sustainable energy storage by transforming waste materials into high-performance lithium-ion battery anodes. Silicon, renowned for its exceptional theoretical capacity, is a promising lithium-ion battery (LIB) anode material, yet its practical application is hindered by severe lithiation-induced volume expansion, structural instability, and high production costs. This study introduces a sustainable strategy to address these challenges by repurposing recycled photovoltaic (PV) silicon through a plasma-assisted vacancy engineering approach. By combining dielectric barrier discharge plasma-assisted milling with bismuth (Bi) modification, controlled vacancy defects are introduced into silicon microparticles, enhancing ion transport and mitigating internal stress. Bi further stabilizes the anode by absorbing mechanical stress and facilitating lithium-ion accommodation at vacancy sites. The resulting plasma induced silicon/carbon/bismuth composite demonstrates outstanding cycling stability and high-rate performance, retaining 1442 mA h g⁻¹ after 300 cycles at 0.5 A g⁻¹ and 525 mA h g⁻¹ after 1000 cycles at 7 A g⁻¹. This scalable and eco-friendly method not only overcomes the inherent limitations of silicon anodes but also transforms PV waste into high-performance LIB materials, advancing sustainable energy storage technologies.