锂离子电容器碳正极材料的研究进展

锂离子电容器是一种采用电容型正极材料、电池型负极材料进行组装的储能器件,结合了锂离子电池与超级电容器两者的优点,兼具高能量密度、高功率密度和长循环寿命。但是由于锂离子电容器还存在正负极动力学过程以及容量不匹配的问题,大大影响了锂离子电容器的电化学性能。通常锂离子电容器的功率密度取决于负极材料,而能量密度取决于正极材料,因此为提高锂离子电容器的能量密度,还需发展具有高比容量和高导电性的正极材料。目前,碳材料因具有低成本、来源广泛、高比表面积和丰富的孔道结构等特点,是一种极具应用潜力的电极材料。综述并分析了各种碳材料(包括活性炭、模板炭、石墨烯和生物炭等)作为锂离子电容器正极材料的电化学性能与优缺点,最后对锂离子电容器正极材料的研究提出了建议与展望。

Research progress of carbon cathode materials for Li-ion capacitors

Lithium ion capacitor is a kind of energy storage device assembled with capacitive positive electrode material and battery negative electrode material. It combines the advantages of both lithium ion battery and super capacitor, and has high energy density, high power density and long cycle life. However, due to the unbalanced capacity and kinetic imbalance between the anode and cathode, the electrochemical performance of lithium-ion capacitors is greatly limited. Generally, the power density of lithium-ion capacitors depends on the negative electrode material, while the energy density depends on the positive electrode material. Therefore, to improve the energy density of lithium-ion capacitors, it is necessary to develop the positive electrode material with high specific capacity and high conductivity. At present, carbon material is a potential electrode material because of its low cost, wide source, high specific surface area and rich pore structure. In this paper, the electrochemical properties, advantages and disadvantages of various carbon materials (including activated carbon, template carbon, graphene and biochar, etc.) as cathode materials for lithium-ion capacitors are reviewed and analyzed. Finally, suggestions and prospects for the research of cathode materials for lithium-ion capacitors are put forward.