钠离子电池磷酸盐正极材料研究进展  

Recent Advances in Phosphate Cathode Materials for Sodium-ion Batteries

作　　者：曹鑫鑫 周江[1] 潘安强[1] 梁叔全[1] Xinxin Cao;Jiang Zhou;Anqiang Pan;Shuquan Liang(School of Materials Science&Engineering,Central South University,Changsha 410083,P.R.China)

机构地区：[1]中南大学材料科学与工程学院,长沙410083

出　　处：《物理化学学报》2020年第5期18-43,共26页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(51872334)资助项目。

摘　　要：近年来,钠离子电池因其原材料丰富、资源成本低廉及安全环保等突出优点,在电化学规模储能领域和低速电动车中具有广阔的应用前景。聚阴离子型磷酸盐具有稳定的框架结构、合适的工作电压和快速的离子扩散路径等特征,是一类极具研究价值和应用前景的钠离子电池正极材料。但是,磷酸盐正极材料电子导电性差和比能量偏低等缺陷限制了其走向实际应用。研究工作者通过体相结构调控和微纳结构设计等手段进行改性研究,旨在提升磷酸盐正极材料的性能表现、推动钠离子储能体系的研究开发。本文综述了钠离子电池磷酸盐正极材料的最新进展,包括正磷酸盐、焦磷酸盐、氟磷酸盐和混合磷酸盐化合物,通过对磷酸盐材料的晶体结构、储钠机理和改性策略等方面的综述,揭示材料成分、结构与电化学性能之间的本征关系,为聚阴离子磷酸盐正极材料的持续改性和新型磷酸盐高压正极材料的探索开发提供指导。Lithium-ion batteries have been widely used in portable electronic devices and electric vehicles because of their high energy density and long cycle life. Sodium-ion batteries have broad application prospects in the areas of large-scale electrochemical energy storage systems and low-speed electric vehicles because of their abundant raw materials, low resource cost, safety, and environmental friendliness. However, the development of sodium-ion batteries has been hindered by the low reversibility, sluggish ion diffusion, and large volume variations of the host materials. Suitable electrode materials with decent electrochemical performance must be primarily explored for the successful use of sodium-ion batteries. Since the electrochemical potential and specific capacities of cathode materials have a major impact on the energy densities of sodium-ion batteries, the development of cathode materials is critical. To date, various Na-insertable frameworks have been proposed, and some cathode materials have been reported to deliver reversible capacities approaching their theoretical values. Among them, transition metal oxides show a high reversible capacity and high working potential, but most of them still possess problems such as irreversible phase transition, air instability, and insufficient battery performance. Another type is the Prussian blue analogs. These materials exhibit a favorable operating voltage, cycling stability, and rate capability;however, the main obstacles to their practical application are the control of lattice defects, thermal instability, and low tap density. Polyanionic phosphates are the most promising cathode materials for sodium-ion batteries and have great research value and application prospects because of their stable framework structure, suitable operating voltage, and fast ion diffusion channels. However, their inherent defects, such as poor electronic conductivity and low theoretical energy density, considerably limit their practical applications. Researchers have conducted modification

关 键 词：钠离子电池 正极材料 磷酸盐 材料结构 电化学性能 能量存储 

分 类 号：O646[理学—物理化学]