高性能锂硫电池用钴/碳复合材料硫宿主

Cobalt/Carbon Composites as Sulfur Hosts for High-Performance Lithium-Sulfur Batteries

锂硫电池由于具有较高的能量密度而被认为是极具发展前景的储能设备之一。然而,硫正极遭遇迟缓的反应动力学、缓慢的电荷转移、大的体积膨胀、严重的多硫化锂穿梭效应,这些问题不可避免地导致锂硫电池表现出低的可逆容量、差的倍率性能、短的循环寿命,限制了锂硫电池的实际应用。本文总结了钴/碳复合材料(包括钴纳米颗粒和钴单原子)作为硫宿主的研究进展。总的来说,钴扮演着电催化剂的角色,能够抑制多硫化锂的穿梭效应,加快电化学反应动力学,促进离子/电子转移以及缓解体积膨胀。同时,我们展望了钴/碳复合材料作为锂硫电池硫宿主的发展前景。本工作可为钴/碳复合材料作为锂硫电池硫宿主提供完整的蓝图和建设性的建议,同时这些策略也可用于其他金属-硫电池。

Lithium-sulfur(Li-S)battery is one of the promising energy storage devices because of its high energy density.However,the sulfur cathode suffers from sluggish electrochemical reaction kinetics,slow charge transfer,large volume expansion and severe shuttle effect of lithium polysulfides inevitably resulting in low reversible capacity,poor rate performance and short cycle life,limiting its practical applications.Herein,the recent progress of cobalt/carbon composites,including cobalt nanoparticles and cobalt single atoms,as the sulfur host materials in Li-S batteries is overviewed.In general,cobalt plays the role of electrocatalyst,which inhibits the shuttle effect of lithium polysulfides,accelerates the electrochemical reaction kinetics,facilitates ion/electron transfer and alleviates volume expansion.Meanwhile,the prospects for the development of cobalt/carbon composites as sulfur hosts in Li-S batteries are proposed.It is expected to offer a whole blueprint and constructive suggestions for the cobalt/carbon composites as sulfur hosts for Li-S batteries,and these strategies can also be effective for other metal-sulfur batteries.