A New Design and Fabrication of Si-C Composite for Lithium-Ion Batteries Anodes

Abstract

For the last few decades, nano-structured silicon anodes are expected to be alternatives to graphitic carbons in rechargeable Li-ion batteries, owing to their extremely high capacities [1,2]. Despite the recent intensive studies with a variety of elaborated nano-Si materials, major use of Si in the anode, i.e. with higher Si wt% in graphite, is still limited. This is due to numerous and entangled issues, the most basic being the complex kinetics and thermodynamics that control the reactions and the huge structural rearrangements, which we have previously elucidated [3]. Based on our previous findings, in this study, we have re-designed and fabricated Si-C composites with scalable methods that can intrinsically overcome the fundamental degradation issues, correlating its electrochemical properties with Li-Si local phase transformations at atomistic scale. Details will be discussed at the conference. [1] Obrovac, M. N. & Christensen, L, Electrochem. Solid-State Lett. 7, A93–A96 (2004). [2] Holzapfel, M. et al., Electrochim. Acta 52, 973 (2006) [3] Ogata, K. Grey, C.P., et al., Nat. Commun. 5, 3217 (2014)