Synthesis And Electrochemical Properties Of High Performance Electrode For Zn Ion Batteries

In the 21st century,human is facing a huge short of energy,so it is urgent to develop a sustainable,green,environmental-friendly and high-efficiency energy storage system.High-performance secondary battery is a key device to realize energy storage and distribution.The aqueous secondary battery with aqueous electrolyte has many advantages,such as green environmental protection,high cost performance,safe use,and high ionic conductivity.It is a battery product with great development potential.Metal zinc has high theoretical capacity,low potential,high abundance,and low toxicity.It is considered to be the most ideal anode material for aqueous batteries.Therefore,domestic and foreign scholars have set off a research boom in secondary zinc-based batteries.On the basis of this,a series of 3D Zn@current collector anode materials were designed and synthesized in this paper,then the effect of the current collector and the additives of electrolyte on the structure and electrochemical performance of the anode was studied.At the same time,the nano-composite electrodeposition technology for preparing anti-corrosion coatings in the industry was introduced for the first time in the field of zinc anodes to solve the problem of zinc corrosion and hydrogen evolution during the cycle.Thanks to the characteristics of nanoparticles,a multi-functional composite coating was obtained to prevent corrosion and suppress hydrogen.And further studied the structure of the electrode material,and its electrochemical performance when applied to zinc-ion batteries.（1）The effect of the current collector on the structure and performance of the zinc anode:choose different current collector copper foil,stainless steel foil,stainless steel mesh,design a series of self-supporting zinc anode,use electrodeposition technology to synthesize Zn@Cu,Zn@SS and Zn@SSM three kinds of anode materials,and compared with commercial zinc foil anode,study the effect of three different current collectors on the electrochemical performance of the deposited product.Among them,the surface morphology distribution of the Zn@SSM anode obtained by electrochemical reaction with the stainless steel mesh as the current collector is the most uniform,the reaction kinetics with the electrolyte interface is the fastest,as well as the reversibility and cycle life of the assembled symmetric battery is the highest.（2）The effect of additives on the structure and performance of zinc anode:stainless steel mesh is selected as the current collector,additives（gelatin,polyvinylpyrrolidone）of different concentrations are used to synthesize Zn@SSM-Gelatin and Zn@SSM-PVP anodes using electrodeposition technology,and the product phase and morphology structure were characterized.The addition of gelatin and PVP contribute to the more uniform surface morphology of the deposited zinc and a reduced particle size,showing the two additives have an promotion effect on the surface morphology of the anodes.（3）Study on modification of zinc anode surface structure:using composite nano-electrodeposition technology,by introducing aluminum oxide（nano-Al₂O₃）and zirconia（nano-Zr O₂）nanoparticles into the electrolyte,using the adjustment of deposition technology parameters,through relevant testing methods have characterized the the product phase and morphology,demonstrating that the two kinds of nanoparticles can promote the surface morphology of the anodes.The tests of reversibility,cycle life and coulombic efficiency were carried out by methods such as AC impedance and galvanostatic charge-discharge,which showed that employing composite electrodeposition to synthesize zinc anode with the addition of nano-Al₂O₃ can improve the electrochemical performance.