钾离子电池磷酸钒基聚阴离子正极材料的研究现状

Status of research on vanadium phosphate-based polyanionic cathode materials for potassium-ion batteries

钾离子电池因具有成本低、能量密度高等优势,被视为锂离子电池的有力替代者。目前,开发容量高、循环性能好的正极材料是推动钾离子电池发展的重要研究方向。聚阴离子型正极材料因具有电压高、循环稳定性和空气稳定性优异等优点而被认为是非常有发展潜力的正极材料。其中,磷酸钒基聚阴离子正极材料具有非常高的氧化还原电位和优异的循环性能,但其可逆容量和电子电导率不佳。本文对磷酸钒基聚阴离子正极材料的研究进行了评述,并详述了具有优异性能的典型正极材料,总结其晶体结构和储钾机理的协同关系,讨论其改进方案和电化学性能。最后,对钾离子电池磷酸钒基聚阴离子正极材料未来的研究方向进行了展望。

Potassium-ion batteries are regarded as promising alternatives to lithium-ion batteries due to their advantages of low cost and high energy density.At present,the development of cathode materials with high capacity and good cycling performance is an important research direction to promote the development of potassium-ion batteries.Among the various cathode materials under investigation,polyanionic cathode materials are considered to be very promising cathode materials due to their advantages of high voltage,excellent cycling stability and air stability.Among these,vanadium phosphate-based polyanionic cathode materials have very high redox potential and excellent cycling performance,but their reversible capacity and electronic conductivity are poor.This paper reviews the research on vanadium phosphate-based polyanionic cathode materials and details typical cathode materials with excellent performance,summarizes the synergistic relationship between their crystal structure and potassium storage mechanism,and discusses their improvement schemes and electrochemical performance.Finally,the future research direction of vanadium phosphate-based polyanionic cathode materials for potassium-ion batteries is presented.