Preparation of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials by Hydrothermal Assisted Sol-Gel Method for Sodium -Ion Batteries  

作　　者：Jiayu LI 

机构地区：[1]Public Experiment Center University of Shanghai for Science and Technology Shanghai 201210,P.R.China

出　　处：《Research and Application of Materials Science》2023年第1期5-10,共6页材料科学与应用（英文）

摘　　要：Na_(3)V_(2)(PO_(4))_(3)(NVP)cathode material of the sodium ion battery(1 C=117 mAh g-1)has a NASICON-type structure,which not only facilitates the rapid migration of sodium ions,but also has a small volume deformation during sodium ion de-intercalation and the main frame mechanism remains unchanged,and thus is seen as an energy storage material for a wide range of applications,but has a limited electronic conductivity due to its structure.In this paper,NVP cathode materials with finer primary particles are successfully prepared using a simple hydrothermal treatment-assisted sol-gel method.The increased pore size of the NVP materials prepared under the hydrothermal process allows for more active sites and more effective resistance to the volume deformation of sodium ions during insertion/extraction processes,effectively facilitating the diffusion of ions and electrons.The Na_(3)V_(2)(PO_(4))_(3) material obtained by the optimized process exhibited good crystallinity in XRD characterization,as well as superior electrochemical properties in a series of electrochemical tests.A specific capacitance of 106.3 mAh g^(-1) at 0.2 C is demonstrated,compared to 96.5 mAh g^(-1) for Na_(3)V_(2)(PO_(4))_(3) without hydrothermal treatment,and cycling performance is also improved with 93%capacity retention.The calculated sodium ion diffusion coefficient(DNa=5.68×10^(-14))obtained after EIS curve fitting of the improved sample illustrates that the pore structure is beneficial to the performance of the Na_(3)V_(2)(PO_(4))_(3)cathode material.

关 键 词：Na3V2(PO4)3 Hydrothermal assisted Sodium ion POROSITY 

分 类 号：TM9[电气工程—电力电子与电力传动]