异氰酸酯抑制LiTFSI电解液铝集流体腐蚀研究  

Isocyanate Inhibits the Corrosion of Aluminum Current Collector

作　　者：周静 王青磊 马奔 李晨阳 许梦霞 王淑渝 苏丽 上官雪慧 李法强 ZHOU Jing;WANG Qinglei;MA Ben;LI Chenyang;XU Mengxia;WANG Shuyu;SU Li;SHANGGUAN Xuehui;LI Faqiang(College of Chemistry and Chemical Engineering of Linyi University,Linyi,276000,China;School of Materials Science and Engineering,Linyi University,Linyi,276000,China)

机构地区：[1]临沂大学化学化工学院,山东临沂276000 [2]临沂大学材料科学与工程学院,山东临沂276000

出　　处：《盐湖研究》2024年第2期1-8,共8页Journal of Salt Lake Research

基　　金：国家自然科学基金(22209065);山东省自然科学基金(ZR2021QE039、ZR2021QE149、ZR2020MB082);山东省高等学校青年创新团队人才引育计划(鲁教科函[2021]51号);临沂大学博士人才科研启动基金(40621022);临沂大学大学生创新创业项目(S202310452150、X202310452296、X202310452510、X202310452511);临沂大学校级教改项目(JG2022M41);临沂市重点研发(2021019zkt)。

摘　　要：商用锂电池普遍采用六氟磷酸锂(LiPF_(6))电解液,但其热稳定性差、易水解。相比之下,双三氟甲烷磺酰亚胺锂(LiTFSI)热稳定性好、不易水解,有望替代LiPF_(6)。然而,LiTFSI电解液对集流体铝箔腐蚀,阻碍了其大规模实际应用。通过添加适量异佛尔酮二异氰酸酯(IPDI),有效解决了上述问题。研究表明,IPDI能够在铝集流体表面生成氮化铝(AlN)保护层,有效地抑制LiTFSI电解液对铝箔的腐蚀。同时,IPDI的引入可有效提高电解液的氧化稳定性,拓宽电化学窗口。此外,添加适量IPDI可改善LiTFSI电解液与锂金属的兼容性,抑制锂枝晶生长,提高Li/Cu沉积剥离库伦效率(CE)。更重要的是,IPDI的引入显著提升锂电池的循环性能和倍率性能,Li/LiFePO_(4)电池充放电循环400圈,容量保持率高达98%。本工作为抑制LiTFSI电解液对铝箔的腐蚀提供了新的设计思路和研究方向,能够促进LiTFSI电解液的实际应用。Lithium hexafluorophosphate(LiPF_(6))electrolyte is widely used in commercial lithium batteries,but it has poor thermal stability and is easy to hydrolyze.In contrast,Lithium bis(trifluoromethylsulphonyl)imide(LiTFSI)has good thermal stability and is stable to hydrolysis,which is expected to replace LiPF_(6).However,the corrosion of current collector aluminum foil by LiTFSI electrolyte hinders its largescale practical application.In this paper,the above problems were effectively solved by adding an appropriate amount of isophorone diisocyanate(IPDI).The results show that IPDI can form a protective layer of aluminum nitride(AlN)on the surface of aluminum current collector,which effectively inhibits the corrosion of aluminum foil by LiTFSI electrolyte.At the same time,the introduction of IPDI effectively improves the oxidation stability of the electrolyte and expands the electrochemical window.In addition,the appropriate amount of IPDI improves the compatibility of LiTFSI electrolyte with lithium metal,inhibits lithium dendrites,and improves the stripping coulombic efficiency(CE)of Li/Cu deposition.More importantly,the introduction of IPDI significantly improves the cycle performance and rate performance of lithium batteries.The capacity retention rate of Li/LiFePO_(4) battery is as high as 98%after 400 cycles.This work provides a new design idea and research direction for inhibiting the corrosion of aluminum foil.

关 键 词：锂电池 异氰酸酯 双三氟甲烷磺酰亚胺锂 铝箔 腐蚀 

分 类 号：TM912[电气工程—电力电子与电力传动]