晶材料NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)的合成与性能

Synthesis and performance of polycrystalline material NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)

在未来储能市场和低速车领域,钠离子电池前景广泛,正极材料的选择很关键。采用共沉淀法并结合高温烧结制备层状氧化物NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM333),借助XRD、SEM和恒流充放电等方法,分析NFM333材料的结构、形貌和电化学性能。NFM333材料为典型的O3结构,呈现多晶特征,作为钠离子电池正极具有较高的比容量、良好的倍率性能和稳定的循环性能。材料以0.3[WTBX]C[WTBZ]在2.0~4.0 V充放电,-20℃、-30℃和-40℃下的放电比容量分别为20℃下的85.55%、72.88%和45.19%。循环伏安(CV)测试发现,较好的电化学性能归因于较高的离子扩散速率和良好的离子迁移动力学。

In the future energy storage market and low-speed vehicle field,sodium-ion battery has broad prospects,the choice of cathode materials is critical.The layered oxide of NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM333)is prepared by co-precipitation method combined with high temperature sintering.By means of XRD,SEM and galvanostatic charge-discharge,the structure,morphology and electro-chemical performance of the NFM333 material are analyzed.NFM333 material has a typical O3 structure and a characteristic of polycrystalline,which can provide high-capacity storage,good rate capability and stable cycle performance as the cathode material of sodium-ion battery.When charged and discharged at 0.3[WTBX]C[WTBZ]in 2.0-4.0 V,the specific discharge capacities of materials at-20℃,-30℃and-40℃are 85.55%,72.88%and 45.19%,respectively,compared with that at 20℃.Cyclic voltammetry(CV)tests prove that the better electrochemical performance can be attributed to the high ion diffusion rate and good ion migration kinetics.