端基对固态电解质离子传输和传热性能的影响  

Effect of End Groups on Ion Transport and Heat Transfer Properties of Solid Polymer Electrolytes

作　　者：王家歧 樊林浩 李伟卓 焦魁[1] 杜青[1] WANG Jiaqi;FAN Linhao;LI Weizhuo;JIAO Kui;DU Qing(State Key Laboratory of Engines,Tianjin University,Tianjin,3300350 China)

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300350

出　　处：《工程热物理学报》2024年第5期1464-1469,共6页Journal of Engineering Thermophysics

基　　金：国家自然科学基金项目(No.51976138)。

摘　　要：本文研究了不同端基聚合物下聚环氧乙烷(PEO)和双(三氟甲磺酰亚胺)锂盐(LiTFSI)固体聚合物电解质的离子扩散系数和热导率,并对其结构性质进行了分析,以研究离子输运和热传导机理。结果表明,以端甲氧基聚环氧乙烷为基体电解质具有较好的离子传输性能,因为更多的自由锂离子能够传输。然而,其导热性质更差,因为声子谱转移到更高的频率,这表明高频声子散射的增强导致热导率降低。这些结论对PEO-LiTFSI电解质设计有着很好的指导意义。In this paper,the ion diffusion coefficients and thermal conductivity of solid polymer electrolytes(SPE)containing poly(ethylene oxide)(PEO)and lithium bis(trifluoromethanesulfonylimine)salt(LiTFSI)with different end group of PEO are investigated and the structural properties are analyzed to study the ion transport and heat conduction mechanisms.The results showed that the poly(ethylene glycol)dimethyl ether(PEGDM)based SPE has better ion transport performance because more free lithium ions can be transported.However,the thermal conductivity of PEGDM is worse because the phonon spectrum is shifted to higher frequencies,which suggests that enhanced high-frequency phonon scattering leads to lower thermal conductivity.These findings provide valuable guide for PEO-LiTFSI electrolyte design.

关 键 词：固体聚合物电解质 分子动力学 离子传输 热导率 

分 类 号：TM911[电气工程—电力电子与电力传动]