钾离子电池高容量铋基合金负极材料研究进展

Research on high-capacity bismuth-based alloy anodes for potassium ion batteries

钾具有储量丰富、成本低、较低的电极电势且与锂元素相似的物理化学性质,因此,钾离子电池有望成为在低速电动车和规模储能等应用领域中部分替代锂离子电池的有力竞争者.由于钾原子半径和质量较大,导致电极材料在嵌钾/脱钾过程中存在较大的体积变化及固体电极中的低离子扩散速率和较差的反应动力学.合金负极具有高的理论比容量、合适的电极电势等优点,是极具前景的钾离子电池负极材料.铋负极的理论储钾容量较高,但充放电过程中存在体积变化、电极材料的粉化等问题.近年来,人们对钾离子电池高容量铋基负极材料及与之相匹配的电解液进行了广泛的研究.本文总结了铋基材料作为高容量负极材料在钾离子电池的应用,对材料结构设计、合成方法和新型电解液等进行综述,同时对合金负极材料的未来发展方向和应用前景进行了展望.

Rechargeable potassium ion batteries(PIBs)have been considered as attractive alternatives for low-speed electric vehicles and large-scale energy storage application owing to the earth abundance,low cost,suitable standard redox potential of potassium element,and similar property with lithium.Nonetheless,large radius and mass of potassium probably induce the huge volume expansion,low diffusion coefficient and poor kinetics during K^(+)intercalation/deintercalation process.Owing to its high theoretical capacity and suitable electrode potential,the alloy-type material has drawn increasing attention as a promising anode candidate for PIBs.Bismuth displays a high theoretical capacity for K^(-)ion storage,while the inherent huge volume expansion and electrode pulverization commonly lead to poor performance.Recent years,extensive studies have been witnessed on high-capacity bismuth-based anode materials and electrolytes for potassium ion batteries.In this review,recent advances of Bi-based anodes in PIBs including material structural design,preparation method and new electrolyte chemistry have been summarized.Finally,future development trends and perspectives of alloy-type anodes are provided.