Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ Structure Of Lithium-rich Materials Regulation, Surface Coating And Electrochemical Performance

Lithium-ion batteries have developed rapidly due to the consumption of fossil fuels and environmental pollution.The cathode material determines the performance of the lithium ion battery.The manganese-based lithium-rich cathode material has attracted the attention of many scholars because of its high specific capacity,high working voltage,no pollution and low cost.Optimizing the size,morphology and structure of the material which is synthesized with different experiment program are considered to be one of the effective ways to improve the electrochemical properties.Therefore,Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ lithium-rich cathode material with different morphologies is synthesized and surface coated treatment to improve the electrochemical properties of the materials.First solvent hot method is used to study the different amount of ethanol to the cathode material morphology and experimental results show that the influence of structure and electrochemical properties,when adding suitable amount of ethanol can be evenly dispersed in diameter about 5?m microsphere structure Li_1.2Mn_0.54Ni_0.13Co_0.13O₂rich lithium anode material the material shows good performance and cycle stabilityIn order to further improve the electrochemical performance of materials,synthesized by using solvent dry hollow hierarchical structure of micro cube Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ rich lithium cathode materials.The experimental results showed that the material was composed of nano-particles with particle size of about50¹00 nm,whose side length was about 2?m hollow hierarchical micro-cube,whose hollow shell thickness was about 200 nm,and charged and discharged at 0.1 C the first-cycle discharge specific capacity of hollow hierarchical micro-cube structural material（MC-LMNC）and shapeless material（SG-LMNC）was 302.1 mAh·g^-1 and280.1 mAh·g^-1,respectively.In order to improve the rate performance of the cathode material of the microsphere structure,ionic conductor LiV₃O₈ was used for surface coating.The experimental results show that the sample exhibits the best electrochemical performance when the LiV₃O₈ coating amount is 3%.Charging and discharging at 0.1 C,the discharge specific capacity of the first cycle was 272.0 mAh·g^-1,After 50 cycles of charging and discharging at 1 C,the capacity retention rate was 83.7%.In order to improve the cycle performance of the microcube structure cathode material,LaF₃ was used for surface coating.The experimental results show that the sample exhibits the best electrochemical performance when the LaF₃ coating amount is 3%.Charging and discharging at 0.1 C,the discharge specific capacity of the first cycle is 254.9 mAh·g^-1and the capacity retention rate after 50 cycles was 71.7%.The results show that the surface coating can effectively improve the electrochemical properties of the material,which provides a reliable basis for the design and optimization of the coating scheme of cathode materials.