Designing Urchin‐Like S/SiO2 with Regulated Pores Toward Ultra‐Fast Room Temperature Sodium–Sulfur Battery

Abstract

AbstractCaptured by high theoretical capacity and low‐cost, Sodium–Sulfur (Na‐S) batteries have been deemed as promising energy‐storage systems. However, their electrochemical properties, containing both cycling and rate properties, still suffer from the notorious “shuttle effect” of polysulfide. Herein, through the effective regulation of pore sizes, a series of S/SiO2 cathode materials are obtained. Benefitting from the abundant pore channels of SiO2 particles, the sulfur loading is as high as 76.3%. Importantly, a suitable pore size can lead to adequate reaction and rapid diffusion behaviors, resulting in excellent electrochemical performances. Specifically, at 2.0 A g−1, the initial capacity of the as‐optimized sample can be up to 1370.6 mAh g−1. Surprisingly, even after 1050 cycles, it could achieve a high reversible capacity of 1280.8 mAh g−1 with an attenuation rate of 0.089%. At 5.0 A g−1, after 500 cycles, the capacity can still remain ≈ 1132.6 mAh g−1 (capacity retention rate, 97.5%). Given this, the work is anticipated to offer an effective strategy for advanced electrodes for Na‐S batteries.