Lee Seungjin, Kim Changseong, Kim Suyeon, Hwang Gyungmin, Yun Deokhee, Cho Ilhyeon, Kim Changseop, Jeon Joonhyeon
Department of Advanced Battery Convergence Engineering, Dongguk University, Seoul 04620, Republic of Korea.
Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, Republic of Korea.
Polymers (Basel). 2025 Jun 26;17(13):1775. doi: 10.3390/polym17131775.
In polymer-based lithium batteries, polymer electrolytes (PEs) exhibit limited ionic conductivity at room temperature (25 °C). To address this issue, this paper describes a hexagonal-structure-based single-ion conducting gel polymer electrolyte (-SICGPE) framework with a robust and efficient cross-linked polymer network, applicable to polymer-based batteries even at 25 °C. The proposed cross-linked polymer network backbone of the -SICGPE, as a semisolid-state thin film type, has the homogeneous honeycomb structure incorporating anion receptor(s) inside each of its hexagonal closed cells and is obtained by cross-linking between trimethylolpropane tris(3-mercaptopropionate) and poly(ethylene glycol) diacrylate in a newly synthesized anion-receptor solution. The excellent structural capability of the -SICGPE incorporating Li/TFSI can enhance ionic conductivity and electrochemical stability by suppressing crystallinity and expanding free volume. Further, the anion receptor in its free volume helps to effectively increase the lithium-ion transference number by immobilizing counter-anions. Experimental results demonstrate dramatically superior performance at 25 °C, such as ionic conductivity (2.46 mS cm), oxidative stability (4.9 V vs. Li/Li), coulombic efficiency (97.65%), and capacity retention (88.3%). These results confirm the developed -SICGPE as a promising polymer electrolyte for high-performance polymer-based lithium batteries operable at 25 °C.
在聚合物基锂电池中，聚合物电解质（PEs）在室温（25°C）下表现出有限的离子电导率。为了解决这个问题，本文描述了一种基于六边形结构的单离子传导凝胶聚合物电解质（-SICGPE）框架，其具有坚固且高效的交联聚合物网络，即使在25°C下也适用于聚合物基电池。所提出的-SICGPE的交联聚合物网络主链为半固态薄膜类型，具有均匀的蜂窝结构，在其每个六边形闭孔内包含阴离子受体，并且是通过三羟甲基丙烷三（3-巯基丙酸酯）与聚乙二醇二丙烯酸酯在新合成的阴离子受体溶液中交联而获得的。包含Li/TFSI的-SICGPE的优异结构性能可以通过抑制结晶度和扩大自由体积来提高离子电导率和电化学稳定性。此外，其自由体积中的阴离子受体有助于通过固定抗衡阴离子有效地提高锂离子迁移数。实验结果表明，在25°C下具有显著优越的性能，例如离子电导率（2.46 mS cm）、氧化稳定性（相对于Li/Li为4.9 V）、库仑效率（97.65%）和容量保持率（88.3%）。这些结果证实了所开发的-SICGPE是一种有前途的聚合物电解质，适用于在25°C下运行的高性能聚合物基锂电池。
