基于离子凝胶电解质的高稳定锌离子电池  

Ionogel electrolytes for high-stable Zn-ion batteries

作　　者：江楠 王宝俊 侯成义 张青红[1] 李耀刚[1] 秦宗益[1] 李克睿 王宏志[1] JIANG Nan;WANG Baojun;HOU Chengyi;ZHANG Qinghong;LI Yaogang;QIN Zongyi;LI Kerui;WANG Hongzhi(State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,College of Materials Science and Engineering,Donghua University,Shanghai 201620,China)

机构地区：[1]东华大学材料科学与工程学院,材料纤维改性国家重点实验室,上海201620

出　　处：《功能材料》2023年第6期6095-6102,共8页Journal of Functional Materials

基　　金：国家自然科学基金(52103253)。

摘　　要：锌离子电池因其安全性高和成本低而备受关注,然而严重的锌枝晶生长损害了电池性能的稳定性。在此,提出了将离子液体加入到聚(偏二氟乙烯-六氟丙烯)(PVDF-HFP)基体中制备离子凝胶电解质,离子液体的阳离子能吸附在锌尖端形成屏蔽层达到使Zn2+均匀沉积的目的。选用了咪唑类离子液体1-乙基-3-甲基咪唑三氟甲磺酸盐(EMIM(OTf))、1-丁基-3-甲基咪唑三氟甲磺酸盐(BMIM(OTf))和1-己基-3-甲基咪唑三氟甲磺酸盐(HMIM(OTf)),探究其阳离子侧链长度对锌枝晶生长的抑制效果。实验证明,由阳离子侧链长度适中的BMIM(OTf)制备出的离子凝胶电解质不仅具有1.87 mS/cm的高离子电导率,还能有效抑制锌枝晶生长,实现了2500 h锌金属负极的长循环稳定性,99.30%的高库伦效率,以及200次循环后全电池83.9%的容量保持率。该工作展示了离子液体凝胶聚合物电解质在高性能的锌离子电池领域的潜在应用价值。Zn-ion batteries have attracted much attention due to their high safety and low cost,however,the growth of Zn dendrites hinders the stability of the battery performance.Here,a strategy is proposed to prepare ionogel electrolytes by incorporating ionic liquids into PVDF-HFP substrate.The cations of the ionic liquids can adsorb onto the Zn tips to form a shielding layer for uniform deposition of Zn 2+.In this work,EMIM(OTf),BMIM(OTf),and HMIM(OTf),that belong to imidazolium ionic liquids,were selected to investigate the inhibitory effect of their cation with different side chain length on the growth of Zn dendrite.It was demonstrated that the ionogel electrolyte,prepared from BMIM(OTf)with moderate side chain length,not only suppressed the growth of Zn dendrites effectively and had high ionic conductivity of 1.87 mS/cm,but also had a stable cycle life of 2500 h.The Coulombic efficiency reached 99.30%after 500 cycles and the capacity retention of the full battery was 83.9%after 200 cycles.This work demonstrates the potential application of ionogel electrolytes in the field of high-performance Zn-ion batteries.

关 键 词：离子液体 锌离子电池 侧链长度 离子凝胶电解质 

分 类 号：TM912[电气工程—电力电子与电力传动]