The Preparation And Performance Of High-performance Tin-based Lithium-ion Battery Negative Materials

In recent years,the demand for electronic devices such as mobile phones and computers has continued to increase.Lithium-ion batteries are the primary source of energy for these portable electronic products and have been the subject of in-depth research by researchers due to their long life,high specific energy,wide operating temperature range,and environmental compatibility.On the other hand,lithium-ion batteries have high potential application to electric vehicles and high research value.The material of the negative electrode of a lithium-ion battery is a central component and plays an important role in improving the overall performance of the battery.SnO₂ is a potential negative electrode material.SnO₂ has many advantages.For example,SnO₂ is rich in properties and has a theoretical capacity of 783mAhg^-1,which is considered one of the promising materials.However,it also has some drawbacks,limiting its widespread use for batteries.An irreversible reaction occurs during the lithium conversion of SnO₂,resulting in a significant loss of initial capacitance and a significant decrease in electrochemical performance.In addition,the large volume expansion causes the electrode material to drop,sputter,and agglomerate,resulting in unstable cycles and low flow performance.To solve these problems,this article uses hydrothermal,ball mill,and other methods to improve and mix SnO₂ materials for higher specific volumes and more stable cycle performance.Prepare the negative electrode material.The contents of the survey are as follows:1.In the first experiment,SnO₂@MnO₂@graphite(SMG)anode material is prepared via a facile ball-milling approach combined with hydrothermal.SnO₂ and MnO₂ nanoparticles are evenly dispersed on numerous sheet-like graphite.MnO₂ can not only play a catalytic role for facilitating the conversion reaction of Sn/Li₂O to SnO₂,but also as a barrier to prevent the coarsening of Sn in the composite.Meanwhile,graphite nanosheets could serve as an ideal volume expansion buffer and good electron conductor.Consequently,the SMG anode delivers superior reversible capacity of 1048.5mAhg^-1,ideal rate capability of 522.2mAhg^-1 at 5.0Ag^-1 and stable long-life cyclic performance with 814.8mAhg^-1 at 1.0Ag^-1 after 1000 cycles.This work provides an available approach to enhance the electrochemical performance of SnO₂-based anode for battery applications.2.In the second experiment,SnO₂@ZrO₂/C composites were also prepared by hydrothermal and high energy ball mill methods.This material has sufficient cycle stability,reversible function,and better throughput performance.The synergistic effect between SnO₂and ZrO₂ nanoparticles provides more lithium storage sites and accelerates diffusion between ions and electrons.Graphite nanosheets effectively suppress the volume expansion of SnO₂nanoparticles,prevent the aggregation of SnO₂ and ZrO₂,and maintain the structural stability of the electrode.In terms of cycle performance,SnO₂@ZrO₂/C nanocomposites show a high reversible capacitance of 688.6mAhg^-1 after 200 cycles with a current density of 0.2mAg^-1.In addition,with a current density of 1.0mAhg^-1,the capacitance will be 690.8mAhg^-1 after200 cycles.3.Finally,based on the previous experiment,the new Mo-SnO₂-graphite ternary composite was prepared by hydrothermal and high energy ball milling.The mixture of Mo and SnO₂ is evenly dispersed in the graphite nanosheets.In Mo-SnO₂-graphite,Mo can suppress the aggregation of Sn nanoparticles,improve the reversible conversion reaction in the lithium process,and improve the electrochemical performance.Therefore,at a current density of 0.2Ag^-1,after 200 cycles,the capacity of the composite Mo-SnO2-graphite is1317.4mAhg^-1,and the flow rate is 514.0mAhg^-1 at a current density of 5.0Ag^-1.And excellent long-term cycle performance.At a current density of 1.0Ag^-1,the current density stabilized at 759.0mAhg^-1 after 950 cycles.The Mo-SnO₂-graphite ternary composite has excellent electrochemical performance,which has been shown to be a very potential anode material for lithium-ion batteries.