Effects of Carboxymethyl Cellulose and Polyvinylidene Fluoride on Electrochemical Sodium‐Ion Storage Performances of Sb/Reduced Graphene Oxide Composites

As anodes for sodium‐ion batteries, antimony‐based anode materials undergo severe volume variation during sodiation/desodiation, leading to low initial Coulombic efficiency (ICE) and poor cycling stability. Several factors, such as the supporting matrices combined with antimony and binders, may impact the performance of antimony‐based anode materials. In this work, we prepared composites of antimony with reduced graphene oxide (Sb/rGO) and demonstrated that rGO as a matrix could prevent the agglomeration of Sb particles, suppress the volume variation of Sb during alloying, and enhance alloying reaction kinetics. We found that with carboxymethyl cellulose (CMC) as a binder, the Sb/rGO shows generally better Na + storage performances than that using polyvinylidene fluoride (PVDF) as a binder, especially the ICE (82.5% with CMC, 62.8% with PVDF). The reason is mainly from the electrochemical defluorination of PVDF.