Preparation And Modification Study Of Lithium Zinc Titanate

Spinel Li₂ZnTi₃O₈（LZTO）has long cycle and high stability,but the low electronic conductivity of LZTO limits its application.In this paper,the electrochemical performance was improved by changing the material morphology,ion doping and preparation of carbonized nanofibers.The research contents and results are as follows:LZTO nanofibers with uniform morphology were prepared by electrospinning,and the optimal preparation process of LZTO anode material（calcined at 750°C for 10 h）was determined.After 40 cycles at 0.1,1,2 and 0.1 C,the reversible capacity of LZTO electrode material was 168 m Ah·g^-1,and after 50 cycles at 1 C,the capacity was up to170.3 m Ah·g^-1.The excellent electrochemical performance of LZTO electrode material can be attributed to the nano-fiber structure,which provides high specific surface area and convenient ion transport path.Mg-doped Li₂Zn_1-xMg_xTi₃O₈ anode materials were prepared by electrospinning.After 40 cycles at different current densities,the capacity of Li₂Zn_0.99Mg_0.01Ti₃O₈ is 202.1m Ah·g^-1,and the capacity is still 180.9 m Ah·g^-1 after 50 cycles at 1 C,which has the best performance.Li₂Zn_1-xMg_xTi₃O₈（x=0,0.01）anode materials were prepared by solid state method and electrospinning method,and the excellent electrochemical performance was obtained by comparing the fiber network structure and Mg doping.LZTO precursor nanofibers were prepared by electrospinning,and carbonized at 750°C for 5 h to obtain carbon coated LZTO/C anode material.The capacity of LZTO/C electrode material was 270 m Ah·g^-1 after 40 cycles at 0.1,1,2 and 0.1 C,and 202.5m Ah·g^-1 after 1000 cycles at 1 C.The excellent electrochemical performance is attributed to the high specific surface area and hierarchical pore structure of LZTO/C fibers,as well as the uniform carbon coverage on the surface of nanofibers,which provides conductive skeleton structure.In summary,the performance of LZTO electrode materials was improved by changing the morphology,ion doping and carbonized fiber,which provides ideas for the development of high capacity and long cycle stability electrode materials.Figure 49;Table 6;Reference 114.