Investigation On Composite Electrolytes And In-situ Solidify Battery

With the development of science and technology,especially the development of electric vehicles,the batteries with high energy density have caught great interests.In order to achieve these goals,lithium metal anode,cathodes with high voltage and capacity,the matching electrolytes and separators have been extensively studied.Due to the nonvolatile,nonflammable,wide electrochemical windows properties of solid electrolytes,solid state batteries are considered the only possible solution.In order to achieve the large-scale commercialization of all solid-state batteries,we need to focus on the controllable deposition of lithium,development of high ionic conductivity electrolytes and manufacturing methods of solid state batteries.In this paper,my research work mainly includes three parts:Regulation of metal lithium deposition behavior,development of composite electrolytes and In-situ solidified method for preparing solid state batteries:1.Four kinds of electrolytes with additives of without,nano-silica,Li NO3,containing Li NO3 and nano-silica are tested by Li/Cu batteries.It clearly shows that the coulomb efficiency and cycle performances are improved.SEM images also show the additives of nano-silica can affect the deposition behaviors.2.The LATP electrolyte and the quasi-solid electrolyte are compounded.The conductivities are measured by EIS,which shows that the composite electrolytes can improve the LATP grain boundary resistance.The data of TG and LSV shows that the composite electrolytes can significantly improve thermal stabilities and oxidation potential.3.Due to the non-flowable and non-wettable properties of solid electrolytes,how to use the existing solid electrolytes to prepare solid-state batteries is critical.We first proposed that solid state batteries can be prepared by In-situ electrochemical reduction methods.First of all,we prove ourguess.Secondly,we prepare solid state batteries with cathode of Li Co O2 and Fe S2 by this method.The solid state battery with Fe S2 exhibits excellent electrochemical properties.