Preparation And Electrochemical Properties Of Li₂znti₃o₈ As Anode Materials For Lithium-ion Batteries

This work focuses on the development of Li₂ZnTi₃O₈ for anodes of lithium batteries,mainly considering two directions.The first is to refine the particles of Li₂ZnTi₃O₈ to study the electrochemical performance.The second aspect is the combination with carbon materials to improve electrical conductivity,exploring the types and proportions of carbon materials.At the same time,composite including carbon is prepared and studied.Keqin,carbon microspheres and SP were added as the gas generator to prepare Li₂ZnTi₃O₈.The experimental results show that the particle size of zinc titanate?LZTO-M?prepared by carbon microspheres as gas medium is the most uniform,and the discharge capacity of the LZTO-M cycle is 209.6?187.2?178?161.8 and 154.4mAh g^-1 at the current density of 0.1?0.5?1.0?2.0 and 3.0 A g^-1,respectively,which are much higher than the LZTO without modification.When the current density is 3.0A g^-1,the discharge capacity of LZTO and LZTO-M is 82.6 mAh g^-1 and 133.6 mAh g^-1 after the 500 cycles,respectively.The results show that the carbon microsphere as the gas medium has the best effect on the negative electrode material,and it benefits from the unique spherical structure.By using five different reagents as solvent to prepare lithium zinc titanate material,the best solvent is sought by the dispersibility of raw materials.The experiment shows that the particle size of LZTO-CA is the most uniform when carbon tetrachloride is used as solvent.At current density of 3.0 A g^-1,the discharge capacity of LZTO-CA is 137 mAh g^-1 higher than that of LZTO.The electrical conductivity of the material was improved by the internal carbon coating with different proportions.It was found that the electrochemical performance of LZTO-4 was the best.The discharge capacity of LZTO-4 was 126 mAh g^-1 after100 cycles at the condition of 3.0 A g^-1,which was 45.1 mAh g^-1 higher than LZTO.The properties of the composite materials were studied by mixing the keqin?carbon microspheres and SP with LZTO.It showed that the electrochemical performance of the LZTO@M material combined with the carbon microspheres was the best.The discharge capacity of the LZTO@M material was 133.4 mAh g^-1 after100 cycles at the current density of 3.0 A g^-1.