Synthesis And Properties Of LiBSB And Its Derivatives

Electrolyte is one of the important parts of the battery,the electro lyte has direct impact on the performance of battery,and the conductivity value and stability are important factors in restricting the performance of battery.Except seeking a new electrolyte material,the optimization and improvement of existing electrolyte materials also has very important significance.At present,to obtain high quality of the secondary battery electrolyte is also one of the current chemical research hot topics.This paper aims to improve the related properties of double salicylic acid boric acid lithium(LiBSB)electrolyte.First of all,salicylic acid,boric acid,oxalic acid and lithium hydroxide hydrate worked as raw materials.And six kinds of lithium boron salt(LiBSB,LiBSB-LiBOB-1,LiBSB-LiBOB-2,LiBSB-LiBOB-3,LiBSB-LiBO B-4 and LiBO B)with different proportion were prepared by solid phase sintering method.The prepared samples were characterized by IR,XRD,SEM,TG and so on.From the results of conductivity test,it can be seen that the conductivity value of LiBSB was lower than others,but the thermal stability of LiBSB was higher than others.When the proportion of oxalic acid and salicylic acid reached a certain amount,the value of conductivity achieved highest.In addition,from the thermogravimetric analysis of the prepared lithium boron salt in zero day and fifteen days,all the lithium boron salt showed hygroscopicity.Secondly,LiBSB/C coating was synthesized by solid phase sintering method with salicylic acid,boric acid,lithium hydroxide hydrate and carboxyl carbon ball(HTC)as raw materials.The products were characterized by IR,XRD,SEM,ect.From SEM and TG analysis,the moisture absorption of LiBSB can be improved when using LiBSB compound coated on HTC.For conductivity test,the results show that the ionic conductivity value of LiBSB/C covering is lower than LiBSB salt.Finally,in order to solve the hygroscopic problem of LiBSB-LiBO B lithium boron salt,LiBSB and LiBOB/C series compounds were synthesized by using salicylic acid,oxalic acid,boric acid,lithium hydroxide and carboxyl carbon(HTC)as raw materials.The products were characterized by IR,XRD,SEM and so on.The contents of B in the products were determined by element analysis.It can be found that hygroscopicity of LiBSB-LiBO B/C was improved and thermostability was all stronger than other LiBSB-LiBO B salts.Conductivity tests of LiBSB-LiBOB/C were carried out in the PC,AN and DMF solvents,respectively.It indicated that the conductivity in the AN is the highest,and conductivity in the PC is lowest.Considering thermogravimetric analysis and conductivity test results,the prod uct got a relative higher conductivity and thermal stability,when HTC was added with a certain amount.