新型锂盐二氟草酸硼酸锂制备的实验性研究

以四氟硼酸锂和无水草酸在助剂四氯化硅作用下制备LiBF2（C2O4），研究了反应温度、反应时间、反应物料比及析晶溶剂二氯甲烷与浓缩产品质量比对产品收率的影响，产品结果利用FTIR和TG进行了确认。实验结果表明，反应温度为30 ℃、反应时间为4 h、反应物料比为1∶0.9、析晶溶剂与浓缩产品质量比为50∶1、析晶溶剂为二氯甲烷时，反应收率为98.3%。电解液体系中添加LiBF2（C2O4）后能有效改善电池的常温循环性能和低温性能。

Study on preparation of new lithium salt—lithium-difluoro(oxalato) borate

A new lithium salt，lithium-difluoro（oxalato） borate was synthesized from the materials of lithium tetrafluoroborate （LiBF₄） and anhydrous oxalic acid assisted by silicon tetrachloride.The influences of reaction temperature，reaction time， mass ratio of the reaction materials，and mass ratio of the crystallization solvent methylene dichloride to concentrated product on the yield of product were investigated.The structures of the objective products were confirmed by FT-IR and TG.The best conditions were described as following：the reaction temperature was 30 ℃，the reaction time was 4 h，the mass ratio of the reaction materials was 1∶0.9，the mass ratio of the crystallization solvent/concentrated product was 50∶1，and crystallization solvent was methylene dichloride.Under the best conditions，the best yield was 98.3%.In addition，adding LiBF₂（C₂O₄） inelectrolyte can effectively improve the cycle performance at room temperature and low temperature performance of battery.