Preparation And Performance Of Li-V-O Based Anode Materials For Aqueous Lithium Ion Battery

The current commercial lithium-ion battery belongs to the organic electrolyte system,which has high cost and poor safety performance.LiV3O8 has the advantage of laminar structure,which facilitates the insertion and extraction of lithium ions,but its cycle performance and rate performance are not satisfactory.The electrode material is doped with Na and K ions to improve the electrochemical performance of the LiV3O8 electrode material.LiV3O8 series doped modified electrode materials,such as Li1-xNax V3O8,LiNaxV3O8 and Li1-xKxV3O8.The electrochemical performance of LiV3O8 was investigated by sol-gel method.The electrode material of Li1-xNaxV3O8 was a rod-like sheet with an average length of about 500 nm and a width of about 200 nm.The doping amount was 8%,the electrochemical properties of the material were best.The initial discharge capacity reached 112.6 m Ah·g-1,2.21 ?,after 50 charge and discharge cycles,the discharge specific capacity was 59.4 m Ah·g-1,the capacity retention was 53%.and 2.96 ? resistance increase.LiNaxV3O8 electrode material was for the bar-like sheet structure,the average length of was 400~500 nm,with a width of about 200 nm;doping amount of 5% when the overall electrochemical properties were best,the first discharge capacity was 95.8m Ah·g-1,the initial resistance was 3.45 ?,After 50 charge-discharge cycles,the specific discharge capacity was 65.8m Ah·g-1,the capacity retention was 68.7%.and 1.97 ? resistance increase.Li1-xKxV3O8 was a rod-like sheet with a particle size of 400~500 nm and a width of about 200 nm.When the doping amount was 8%,the overall electrochemical performance of Li1-xKxV3O8 was best,the initial discharge specific capacity reached 175.9 m Ah·g-1,was 1.93 ?.After 50 charge and discharge cycles,the specific discharge capacity was 130.9 m Ah·g-1,the capacity retention was 51.1%.and 3.50 ? resistance increase.