Ruan Zhefei, Du Yuzhe, Pan Hongfei, Zhang Ruiming, Zhang Fangfang, Tang Haolin, Zhang Haining
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory, Foshan 528200, China.
Polymers (Basel). 2022 May 11;14(10):1950. doi: 10.3390/polym14101950.
A solid-state polymer electrolyte membrane is formed by blending poly(vinylidene fluoride-co-hexafluoropropylene) with the synthesized copolymer of poly(methyl methacrylate-co-1-vinyl-3-butyl-imidazolium bis(trifluoromethanesulfonyl)imide, in which lithium bis(trifluoromethane)sulfonimide molecules are applied as the source of lithium ions. The accordingly formed membrane that contains 14 wt.% of P(MMA-co-VBIm-TFSI), 56 wt.% of PVDF-HFP, and 30 wt.% of LiTFSI manifests the best electrochemical properties, achieving an ionic conductivity of 1.11 × 10 S·cm at 30 °C and 4.26 × 10 S·cm at 80 °C, a Li-ion transference number of 0.36, and a wide electrochemical stability window of 4.7 V (vs. Li/Li). The thus-assembled all-solid-state lithium-ion battery of LiFePO/SPE/Li delivers a discharge specific capacity of 148 mAh·g in the initial charge-discharge cycle at 0.1 C under 60 °C. The capacity retention of the cell is 95.2% after 50 cycles at 0.1 C and the Coulombic efficiency remains close to 100% during the cycling process.
通过将聚（偏二氟乙烯 - 共 - 六氟丙烯）与聚（甲基丙烯酸甲酯 - 共 - 1 - 乙烯基 - 3 - 丁基咪唑双（三氟甲磺酰）亚胺）的合成共聚物共混形成固态聚合物电解质膜，其中双（三氟甲烷）磺酰亚胺锂分子用作锂离子源。相应形成的膜含有14 wt.% 的P（MMA - co - VBIm - TFSI）、56 wt.% 的PVDF - HFP和30 wt.% 的LiTFSI，表现出最佳的电化学性能，在30°C时离子电导率为1.11×10 S·cm，在80°C时为4.26×10 S·cm，锂离子迁移数为0.36，电化学稳定窗口宽达4.7 V（相对于Li/Li）。由此组装的LiFePO/SPE/Li全固态锂离子电池在60°C下0.1 C的初始充放电循环中放电比容量为148 mAh·g。在0.1 C下50次循环后，电池的容量保持率为95.2%，并且在循环过程中库仑效率保持接近100%。
