Enhancing the Electrochemical Performance of SbTe Bimetallic Anodes for High-Performance Sodium-Ion Batteries: Roles of the Binder and Carbon Support Matrix

Abstract

Synergism between the alloy materials and the carbon support matrix, in conjunction with the binder and electrolyte additives, is of utmost importance when developing sodium-ion batteries as viable replacements for lithium-ion batteries. In this study, we demonstrate the importance of the binder and carbon support matrix in enhancing the stabilities, cyclabilities, and capacity retentions of bimetallic anodes in sodium-ion batteries. SbTe electrodes containing 20%, 30%, and 40% carbon were fabricated with polyvinylidene fluoride (PVDF) and polyacrylic acid (PAA) binders, and electrochemically evaluated at a current rate of 100 mA g−1 using electrolytes with 0%, 2%, and 5% added fluoroethylene carbonate (FEC). The electrodes with the PVDF binder in cells with 5% FEC added to the electrolyte showed capacity retentions that increased with increasing carbon percentage, delivering reversible capacities of 34, 69, and 168 mAh g−1 with 20%, 30%, and 40% carbon; these electrodes retained 8.1%, 17.4%, and 44.8% of their respective capacities after 100 cycles. However, electrodes composed of the PAA binder in cells with 5% FEC added to the electrolyte delivered reversible capacities of 408, 373, and 341 mAh g−1 with 20%, 30%, and 40% carbon; 93.5%, 93.4%, and 94.4% of their respective capacities were retained after 100 cycles. The carbon support matrix plays a significant role in improving the stability, cyclability, and capacity retention of the electrode. However, when the tradeoff between capacity and cyclability associated with carbon percentage is considered, the binder plays a significantly more prominent role in achieving high capacities, high cyclabilities, and enhanced retention rates.

Advanced Anode Materials for Rechargeable Sodium-Ion Batteries

“…Another chalcogenide material, tellurides (such as SnTe, Sb 2 Te 3 , Bi 2 Te 3 ), with higher conductivity, larger interplanar spacing and higher density compared with oxides, sulfides and selenides, have been widely adopted for SIBs anodes. − These intrinsic features allow outstanding rate ability and high theoretical volumetric capacity. , It was revealed that the reaction products between Na-ion and Sb 2 Te 3 were Na 3 Sb and Na 2 Te . Later, the sodiation-desodiation process of Bi 2 Te 3 anode was investigated via in situ XRD and ex situ HRTEM techniques .…”

“…252−255 These intrinsic features allow outstanding rate ability and high theoretical volumetric capacity. 256,257 It was revealed that the reaction products between Na-ion and Sb 2 Te 3 were Na 3 Sb and Na 2 Te. 258 Later, the sodiationdesodiation process of Bi 2 Te 3 anode was investigated via in situ XRD and ex situ HRTEM techniques.…”

Unleashing the Potential of Sodium‐Ion Batteries: Current State and Future Directions for Sustainable Energy Storage

“…[ 215 ] A comparative study on different binders with electrolyte additive effects on bimetallic SbTe anode in SIB is recently published. [ 216 ] The electrode with the PVDF binders with FEC (5%) as an additive to the electrolytes and containing (20, 30, and 40)% carbon were outperformed by the PAA binder with identical additive. The PVDF cell showed reversible capacities increment with the increase in carbon contents as (34, 69, and 168) mAh g −1 , with a retention of (8.1, 17.4, and 44.8)%, respectively, after 100 cycles.…”

Topological Dirac Semimetal Phase in Bismuth Based Anode Materials for Sodium-Ion Batteries

“…However, DFT calculations predict that Na 3 Sb is prone to being an insulator [25]. (The electronic conductivity of the anode could be activated, for example, by using carbon matrices [26]). Na 3 Bi, on the other hand, is a three-dimensional (3D) nontrivial Dirac semimetal [27], and a number of recent studies discuss Na 3 Bi as an anode material in sodium-ion batteries [28][29][30][31][32].…”