钠离子电池正极材料磷酸钒钠的研究进展

Research Progress of Vanadium Phosphate Sodium for Cathode Material of Na-ion Batteries

NASICON型的磷酸钒钠具有三维框架结构,充放电电压平台较高,储能容量大,循环稳定性好,是一种很具前景的钠离子电池正极材料。本文综合了大量磷酸钒钠有关文献的研究成果,介绍了磷酸钒钠的晶体结构与电化学性能,以及磷酸钒钠的常用合成方法与改性手段。目前所进行的研究中,最常见的是以固相法和溶胶凝胶法合成,也包括喷雾干燥法、水热法、静电纺丝法等,改性手段主要包括以不同碳源进行碳包覆、离子掺杂、与导电物质复合以及材料纳米化四种,磷酸钒锂材料在改性后其导电性与电化学性能均有明显提高,这有望推进钠离子电池的实用化进程。

N ASIC ON type vanadium phosphate sodium has 3D frame structure, relative high charge/ discharge voltage platform, high storage capacity and good cycle stability. Thus it is a prospective cathode material for Na-ion batteries. By means of plentiful literature sum-up, the crystal structure , electrochemical performance, synthetic and modified methods were introduced. In the current study, solid state method and sol-gel method are the most popular synthetic ways, and besides, spray drying process, hydrothermal method, electrostatic spinning process are also available. The mainly four modified methods are carbon-coating by different carbon source, ion doping, recombination with high conductive substances and nanocrystallization. After modification, conductive and electrochemcial performance of vanadium phosphate sodium were improved impressively, thus the utility progress can be promoted, effectively.