Preparation Of Mesoporous Silica Microspheres And Study On Gel Polymerization Dielectric Composite System

The sustainable development of new energy technologies is one of the urgent problems to be solved in the world today.With the further research,the development of new inorganic nano-filler particles with good electrochemical activity for lithium metal battery electrolytes has become a research hotspot.Silica has high research value in the field of electrochemistry due to its good physical and chemical properties.Mesoporous silica microspheres not only possess the non-toxic,odorless,and environmentally friendly properties of silica itself,but also have a high specific surface area and a complex pore structure.Therefore,the design of mesoporous silica fillers that promote electrochemical performance for electrolytes of lithium metal batteries has become a new research direction.In this paper,the traditional St?ber method is further adjusted to obtain silica nanoparticles with two different structural characteristics,which expands its application in the field of electrochemistry and further provides design significance for the structure design of electrolyte fillers.The research focuses of this article are as follows:1)By adjusting the St?ber method,adding cetyltrimethylammonium bromide?CTAB?as a template agent,and triethanolamine?TEAH₃?as a mineralizer,composite microspheres were obtained by hydrolysis of TEOS After removing the template by calcination,bayberry-like SiO₂ nanospheres were finally obtained.The BET test found that it has an ultra-high specific surface area.As a filler in polymer electrolytes,it is expected to promote the dissociation of lithium salts,thereby improving the electrochemical performance of lithium metal batteries.2)Further adjust the SiO₂ synthesis environment,greatly reduce the use of mineralizers and add sodium dodecyl sulfonate?SDS?as a mixed template agent,and obtain SiO₂ microspheres with uniform dendritic structure after calcination.The BJH test found that it has ultra-high pore volume structure characteristics.When used as an electrolyte filler,it is expected to optimize the lithium ion migration channel.3)Compare the thermodynamics and electrochemistry performance of four different composite gel electrolytes?blank sample without filler,10%bayberry-like SiO₂ nanospheres,10%uniform dendritic SiO₂ nanospheres,and 10%commercial SiO₂nanospheres?.Through the charge-discharge cycle test and rate performance test,it was found that the electrochemical performance of the SiO₂ microsphere filler with mesoporous structure has been significantly enhanced,and at high rates,optimizing lithium ion migration channels is more important than increasing the number of lithium ions.