聚阴离子型钠离子电池正极材料的研究进展  

Research Advances in Polyanion-Type Cathodes for Sodium-Ion Batteries

作　　者：潘雯丽 关文浩[1] 姜银珠[1] Wenli Pan;Wenhao Guan;Yinzhu Jiang(State Key Laboratory of Silicon Materials,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,P.R.China)

机构地区：[1]浙江大学材料科学与工程学院,硅材料国家重点实验室,杭州310027

出　　处：《物理化学学报》2020年第5期63-74,共12页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(51722105);浙江省自然科学基金(LR18B030001);中央高校基本科研业务费(2018XZZX002-08)资助项目。

摘　　要：作为钠离子电池正极材料的体系之一,聚阴离子型化合物具有成本低廉和安全性高的优点,适合于大规模固定式储能系统。实时平衡电网电力供需水平对正极材料的倍率性能提出了更高的要求,而聚阴离子材料虽然存在离子扩散通道,但缺乏电子传输路径,导致其动力学性能不佳。为了挖掘影响聚阴离子型正极动力学性能的因素,本文以结构为基础,对影响聚阴离子正极离子扩散行为的本征原因作了阐述,再从表面修饰和形态设计入手,对目前研究较多的改善电极表面及界面处离子和电子扩散的策略作了总结与点评,然后从材料的分级结构回归到鲜见报导的元素掺杂和取代,从本质上提出优化动力学性能的方案,并展望了进一步提高正极材料倍率性能的方向。本文可为高倍率的聚阴离子型正极材料及其他材料的开发提供基本理论和实践依据。Because of their high energy density and long cycle life, lithium-ion batteries(LIBs) have dominated the portable electronics market for over 20 years. However, with the increasing demand for largescale energy storage systems for grid applications, the price of Li resources has increased owing to the low abundance of Li in Earth’s crust and non-uniform distribution on the planet. Because Na has similar physical and chemical properties as Li and is an abundant natural resource, room-temperature sodium-ion batteries(SIBs) are expected to be among the most promising next-generation large grid energy storage devices. It is known that the cathode, anode, separator and electrolyte materials are the main components of batteries. Among these, Na-containing cathode materials are of critical importance. As a cathode material for SIBs, polyanion-type compounds have become a hot research topic owing to their versatile structural frameworks, high thermal stabilities, high ambient stabilities even in the charging state, small volume changes, tunable operating voltage by tuning the chemical environment of the polyanions, and high operating voltages owing to the inductive effects of the polyanionic groups(PO43-, SO42-, SO44-, etc.). In particular, for Earth’s abundant resources and inherent stability, polyanion-based compounds are suitable for large-scale stationary energy storage. Taking grid balancing into account, batteries with fast charge rates are in demand, which requires cathodes having high rate capability. However, despite the presence of ion diffusion channels in polyanion compounds, the electronic transport channels are blocked owing to the separation of the metal polyhedral and the strong electronegativity of the anions, leading to poor electron conductivity, which largely limits the rate capability of polyanion compounds. Therefore, it is crucial to understand the inherent limitation of the kinetics in terms of the structural aspects and to determine strategies for improving the rate capability. This review dis

关 键 词：钠离子电池 聚阴离子型正极 高倍率性能 离子扩散 电子传输 

分 类 号：O646[理学—物理化学]