LiV_3O_8在Li_2SO_4水溶液中的电化学性能(英文)

Electrochemical Behavior of LiV_3O_8 in Aqueous Li_2SO_4 Solution

采用低温固相法合成了具有纳米结构的LiV_3O_8材料.扫描电子显微镜(SEM)及透射电子显微镜(TEM)测试显示该材料具有纳米结构.X射线衍射(XRD)表明该材料属于单斜晶系,P2_1Im空间群.并采用循环伏安法(CV)及电化学阻抗谱图测试对该材料在1、2 mol·L^(-1)Li_2SO_4水溶液及饱和Li_2SO_4水溶液中的电化学行为进行了研究.结果表明,LiV_3O_8在饱和Li_2SO_4水溶液中具有最好的电化学性能.以LiV_3O_8作为负极材料,LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2作为正极材料,饱和Li_2SO_4水溶液作为电解液组成了水性锂离子电池,进行恒流充放电测试,结果表明,在0.5C(1C=300 mA·g^(-1))的充放电倍率下,该水性锂离子电池的首次放电比容量为95.2 mAh·g^(-1),循环100次后仍具有37.0 mAh·g^(-1)的放电比容量.

Nanostructured LiV_3O_8 powder was synthesized by a low-temperature solid-state method. Scanning election microscopy（SEM） and transmission electron microscopy（TEM） show that the as-prepared material is composed of nanostructured particles.X-ray diffraction（XRD） measurements indicate that the as-prepared material has a monoclinic structure with a space group of P2_1/m.The electrochemical properties of the LiV_3O_8 electrodes in 1 mol·L^（-1） Li_2SO_4,2 mol·L^（-1） Li_2SO_4,and saturated Li_2SO_4 aqueous electrolytes were studied using cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS） in this work.The results show that the LiV_3O_8 electrode in the saturated Li_2SO_4 electrolyte has the best electrochemical properties.An aqueous rechargeable lithium battery（ARLB） containing a LiV_3O_8 anode,a LiNi_（1/3）Co_（1/3）Mn_（1/3）O_2 cathode,and a saturated Li_2SO_4 electrolyte was fabricated. The battery delivered an initial capacity of 95.2 mAh·g^（-1） and retained a capacity of 37.0 mAh·g^（-1） after 100 cycles at a charge-discharge rate of 0.5C（1 C=300 mA·g^（-1））.