Blocky Sb/C Anodes with Enhanced Diffusion Kinetics for High-Rate and Ultra-Long Cyclability Sodium Dual-Ion Batteries

Graphical Blocky road : Sodium dual-ion batteries (SDIBs) with Sb/C/G anode and expanded graphite (EG) as cathode, NaClO 4 as salts can deliver superior electrochemical performance, for example, a high discharge capacity of 376 mA h g −1 with a higher ICE (69.1 %) at current density of 500 mA g −1 , a excellent cycling stability (73 mA h g −1 is retained even after 1400 cycles at current density of 1000 mA g −1 ), and high stable CE of 99.0 %. Sodium ion-based dual ion batteries (SDIBs) have attracted increasing attentions for their high operative voltages and low cost, but their poor long-term cycling stability and rate capability largely hinder their practical applications. Here, an optimized anode-antimony/carbon/graphene (Sb/C/G) composite for SDIBs is designed. Sb nanoparticles (NPs) not only can enhance the specific capacity but also facilitate the Na + diffusion kinetics. The continuous conductive carbon matrix can promote the electron transfer process and accommodate volume changes of Sb NPs during sodiation/desodiation. Therefore, superior electrochemical performance, for example, a high discharge capacity of 376 mA h g −1 with a higher ICE (69.1 %) at current density of 500 mA g −1 , an excellent cycling stability (73 mA h g −1 is retained even after 1400 cycles at current density of 1000 mA g −1 ), and high stable CE of 99.0 %. Our study offers a suitable design for Na + -based batteries anode structure and accelerates their practical applications.