锂源对双草酸硼酸锂合成的影响
来源期刊：中南大学学报(自然科学版)2012年第12期
论文作者：陆源 尹周澜 卜芃 李新海 王志兴 郭华军
文章页码：4633 - 4637
关键词：锂源；锂离子电池；精馏法；双草酸硼酸锂
Key words：lithium source; Li-ion battery; solvent boiling differential method; lithium bis (oxalate)borate
摘 要：用改进的固相合成方法及精馏提纯方法，获得一种含有螯合硼酸根离子的电解质锂盐-双草酸硼酸锂(LiBOB)。分别选取4种含锂化合物作为锂源，采用红外光谱、X线衍射方法和化学定量分析方法，比较不同锂源对合成LiBOB的产物纯度、电化学性能的影响。研究结果表明：由LiOH·H2O合成的粗产品1次纯化纯度为99.4%，2次纯化纯度为99.8%；由Li2C2O4合成的LiBOB杂相较多；由CH3COOLi·2H2O合成的LiBOB含水分较多。用不同锂源合成的LiBOB配制成0.7 mol/L LiBOB/(EC/PC/DMC=1:1:3，质量比)电解液，组装成LiM2O4/Li电池进行电池循环性能的测试。LiOH·H2O和Li2CO3作为锂源合成的LiBOB具有良好的电化学性能，Li2C2O4和CH3COOLi·2H2O作为锂源合成的LiBOB电化学性能较差。
Abstract: A new lithium salt(LiBOB) based on a chelated borate anion, BOB [Bis (oxalate) borate] was synthesized by an improved solid-state method and purified by rectification. Four different lithium-containing compounds were selected as lithium sources. The synthesized LiBOB was identified by infrared spectrum，X-ray diffraction(XRD) and quantitative chemical analysis. The effects of lithium sources on the purity and electrochemical performance of LiBOB products were investigated. The results show that the purity of LiBOB synthesized from LiOH·H2O is larger than 99.4% after one time of purification and larger than 99.8% after two times of purification. The LiBOB synthesized from Li2C2O4 has impurity phases and that from CH3COOLi·2H2O has high water content. The lithium manganese dioxide button cell was assembled with 0.7 mol/L LiBOB/(EC:PC:DMC =1:1:3, mass ratio) as electrolyte and the cycle performance of the cell was tested. LiBOB with LiOH·H2O or Li2CO3 as lithium sources shows better electrochemical performance while that with Li2C2O4 or CH3COOLi·2H2O as lithium sources shows poor electrochemical performance.
陆源1，尹周澜1，卜芃1，李新海2，王志兴2，郭华军2
(1. 中南大学 化学化工学院，湖南 长沙，410083；
2. 中南大学 冶金科学与工程学院，湖南 长沙，410083)
摘 要：用改进的固相合成方法及精馏提纯方法，获得一种含有螯合硼酸根离子的电解质锂盐-双草酸硼酸锂(LiBOB)。分别选取4种含锂化合物作为锂源，采用红外光谱、X线衍射方法和化学定量分析方法，比较不同锂源对合成LiBOB的产物纯度、电化学性能的影响。研究结果表明：由LiOH·H2O合成的粗产品1次纯化纯度为99.4%，2次纯化纯度为99.8%；由Li2C2O4合成的LiBOB杂相较多；由CH3COOLi·2H2O合成的LiBOB含水分较多。用不同锂源合成的LiBOB配制成0.7 mol/L LiBOB/(EC/PC/DMC=1:1:3，质量比)电解液，组装成LiM2O4/Li电池进行电池循环性能的测试。LiOH·H2O和Li2CO3作为锂源合成的LiBOB具有良好的电化学性能，Li2C2O4和CH3COOLi·2H2O作为锂源合成的LiBOB电化学性能较差。
关键词：锂源；锂离子电池；精馏法；双草酸硼酸锂
LU Yuan1, YIN Zhou-lan1, BU Peng1, LI Xin-hai2, WANG Zhi-xing2, GUO Hua-jun2
(1. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
2. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China)
Abstract:A new lithium salt(LiBOB) based on a chelated borate anion, BOB [Bis (oxalate) borate] was synthesized by an improved solid-state method and purified by rectification. Four different lithium-containing compounds were selected as lithium sources. The synthesized LiBOB was identified by infrared spectrum，X-ray diffraction(XRD) and quantitative chemical analysis. The effects of lithium sources on the purity and electrochemical performance of LiBOB products were investigated. The results show that the purity of LiBOB synthesized from LiOH·H2O is larger than 99.4% after one time of purification and larger than 99.8% after two times of purification. The LiBOB synthesized from Li2C2O4 has impurity phases and that from CH3COOLi·2H2O has high water content. The lithium manganese dioxide button cell was assembled with 0.7 mol/L LiBOB/(EC:PC:DMC =1:1:3, mass ratio) as electrolyte and the cycle performance of the cell was tested. LiBOB with LiOH·H2O or Li2CO3 as lithium sources shows better electrochemical performance while that with Li2C2O4 or CH3COOLi·2H2O as lithium sources shows poor electrochemical performance.
Key words:lithium source; Li-ion battery; solvent boiling differential method; lithium bis (oxalate)borate
