A new two-step synthetic method was successfully developed to simplify the recrystallization process of lithium difluoro(oxalate)borate(LiODFB).Meanwhile,the purity of LiODFB as-prepared was determined by NMR,ICP-AES ...A new two-step synthetic method was successfully developed to simplify the recrystallization process of lithium difluoro(oxalate)borate(LiODFB).Meanwhile,the purity of LiODFB as-prepared was determined by NMR,ICP-AES and Karl Fisher measurements,respectively.The as-prepared LiODFB presents a high purity up to 99.95%.Its metal ions and water contents are under good control as well.Besides,its structure information and thermal properties were confirmed by FTIR,Raman and DSC-TGA analyses,respectively.LiODFB exerts fine thermostability and hypo-water-sensitivity and its structure information agrees well with previous literature.Furthermore,a combination of phase diagram and Raman spectroscopy were utilized to study the thermal phase behavior and ions coordination of LiODFB-DMC binary system to optimize the synthesis and recrystallization process.Although there are three types of molecular interaction forms(CIPs,AGG-IIa,AGG-IIIb)in LiODFB-DMC binary system,LiODFB can only be isolated as large single crystal solvate as LiODFB·(DMC)3/2 by slowly cooling subjected to the nucleation kinetics.Therefore,the fundamental information of our work is helpful in accelerating the application of LiODFB in Li-ion secondary batteries.展开更多
基金Project(51371198)supported by the National Natural Science Foundation of ChinaProject(K1202039-11)supported by the Science and Technology Project of Changsha,China
文摘A new two-step synthetic method was successfully developed to simplify the recrystallization process of lithium difluoro(oxalate)borate(LiODFB).Meanwhile,the purity of LiODFB as-prepared was determined by NMR,ICP-AES and Karl Fisher measurements,respectively.The as-prepared LiODFB presents a high purity up to 99.95%.Its metal ions and water contents are under good control as well.Besides,its structure information and thermal properties were confirmed by FTIR,Raman and DSC-TGA analyses,respectively.LiODFB exerts fine thermostability and hypo-water-sensitivity and its structure information agrees well with previous literature.Furthermore,a combination of phase diagram and Raman spectroscopy were utilized to study the thermal phase behavior and ions coordination of LiODFB-DMC binary system to optimize the synthesis and recrystallization process.Although there are three types of molecular interaction forms(CIPs,AGG-IIa,AGG-IIIb)in LiODFB-DMC binary system,LiODFB can only be isolated as large single crystal solvate as LiODFB·(DMC)3/2 by slowly cooling subjected to the nucleation kinetics.Therefore,the fundamental information of our work is helpful in accelerating the application of LiODFB in Li-ion secondary batteries.