Electrochemical Performance of Porous Carbon/Tin Composite Anodes for Sodium‐Ion and Lithium‐Ion Batteries

TLDR

The study systematically investigates the electrochemical performance of mesoporous carbon/tin anodes in sodium‑ion and lithium‑ion batteries, aiming to understand the Sn–Na reaction mechanism to guide the design of new alloy‑based anodes. The mesoporous C/Sn anodes show similar cycling stability but lower capacity and poorer rate capability in Na‑ion batteries compared to Li‑ion batteries, with desodiation potentials about 0.21 V lower, due to the larger Na⁺ size causing slow diffusion and large volume changes during alloy/dealloy reactions.

Abstract

Abstract The electrochemical performance of mesoporous carbon (C)/tin (Sn) anodes in Na‐ion and Li‐ion batteries is systematically investigated. The mesoporous C/Sn anodes in a Na‐ion battery shows similar cycling stability but lower capacity and poorer rate capability than that in a Li‐ion battery. The desodiation potentials of Sn anodes are approximately 0.21 V lower than delithiation potentials. The low capacity and poor rate capability of C/Sn anode in Na‐ion batteries is mainly due to the large Na‐ion size, resulting in slow Na‐ion diffusion and large volume change of porous C/Sn composite anode during alloy/dealloy reactions. Understanding of the reaction mechanism between Sn and Na ions will provide insight towards exploring and designing new alloy‐based anode materials for Na‐ion batteries.