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Solid-state Graft Copolymer Electrolytes for Lithium Battery Applications
Published on: August 12, 2013
晶体聚合物电解质中的离子导电率 PEO6:LiXF6,X = P,As,Sb
Zlatka Stoeva1, Isabelle Martin-Litas, Edward Staunton
1School of Chemistry, University of St. Andrews, Purdie Building, North Haugh, St. Andrews KY16 9ST, UK.
Journal of the American Chemical Society
|April 10, 2003
概括
晶体聚合物电解质导电离子,挑战了只有无形材料是导电的观点. 这些固态材料对先进的电池技术具有前途.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 聚合物科学 聚合物科学
背景情况:
- 离子导电聚合物提供固态离子导电性,对于电池等设备至关重要.
- 传统上,聚合物的离子导电性与玻璃过渡温度以上的无形相相关.
- 晶体聚合物电解质被广泛认为是绝缘体.
研究的目的:
- 为了研究晶体聚合物电解质的离子导电性.
- 挑战对聚合物电解质中离子运输的既定理解.
- 探索用于电池应用的晶体聚合物电解质中的结构性质关系.
主要方法:
- 结晶聚合物电解质的合成和表征:聚乙烯氧化物:LiXF6 (X = P,As,Sb).
- 在晶体和无形阶段测量离子导电性.
- 分析晶体结构以了解传导路径.
- 研究分子质量对离子导电性的影响.
主要成果:
- 在三种晶体聚合物电解质 (聚乙烯氧化物) (6):LiXF (6)) 中表现出显著的离子导电性.
- 与相似的无形相相比,在晶相中观察到较高的离子导电性.
- 在6:1复合体中发现了类似的导电性,与晶体结构瓶相关.
- 报告说,由于晶体体尺寸较大,离子导电性增加,分子量减少.
结论:
- 结晶聚合物电解质可以表现出相当大的离子导电性,与此前的假设相反.
- 离子导电性受到聚合物的分子量和晶体尺寸的影响.
- 这些发现为开发用于储能设备的先进固态电解质开辟了新的途径.
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