### 聚阴离子型钠离子电池正极材料的研究进展

• 收稿日期:2019-05-02 录用日期:2019-06-18 发布日期:2019-06-24
• 通讯作者: 姜银珠 E-mail:yzjiang@zju.edu.cn
• 作者简介:姜银珠，浙江大学教授，1983年出生。1998–2007年在中国科学技术大学本硕博学习，2007–2010年分别在亚申科技研发中心、英国Heriot-Watt大学、德国Bielefeld大学从事研究工作，2010年起加入浙江大学。主要从事电化学储能材料与器件研究
• 基金资助:
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)

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

Wenli Pan,Wenhao Guan,Yinzhu Jiang*()

• Received:2019-05-02 Accepted:2019-06-18 Published:2019-06-24
• Contact: Yinzhu Jiang E-mail:yzjiang@zju.edu.cn
• Supported by:
the National Natural Science Foundation of China(51722105);the Zhejiang Provincial Natural Science Foundation, China(LR18B030001);the Fundamental Research Funds for the Central Universities, China(2018XZZX002-08)

Abstract:

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 large-scale 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−, SiO44−, 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 discusses the intrinsic reasons for the factors impacting ion diffusion based on the different structures of polyanion-type cathodes. From the perspectives of surface modification and morphology, strategies for enhancing the transport of sodium ions and electrons at the surface and interface are summarized and discussed. Then, from the standpoint of the hierarchical structures of materials to the design of a structural framework, which have been rarely reported, this review proposes schemes that intrinsically enhance the rate capability of polyanion compounds and provides a perspective on developments that can further improve the rate capability of cathode materials. This review provides suggestions for designing and optimizing high-rate polyanion-type and other kinds of cathodes from both academic and practical viewpoints.

MSC2000:

• O646