Free Standing Flexible Lithium-Ion Polymer Electrolyte Membranes formed by Photopolymerization

通过光聚合形成的自立式柔性锂离子聚合物电解质膜

• 批准号: 1161070
• 负责人: Thein Kyu
• 金额: $ 41万
• 依托单位: University of Akron
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1161070&HistoricalAwards=false
• 关键词: Free; Standing; Flexible; Lithium; Ion

TECHNICAL SUMMARY: The principal objectives of this project are (1) to demonstrate how the fundamental understanding of ternary phase diagrams may provide guidance to facile fabrication of free-standing flexible polymer batteries and (2) to elucidate governing principles for creation of periodic arrays of ionic channels aligned homeotropically via photolithography and having well defined domain size and periodicity. These aligned channels produced by photopolymerization-induced phase separation will not only serve as ion conducting wires (or micro-channels), but also increase the ion concentration without sacrificing the mechanical strength and integrity of the free-standing battery membranes. Such periodic arrays of channels with perpendicular orientation have been highly sought for enhanced electron/exciton transport in the development of organic materials for solar cell applications as well as for efficient Li+ ion transport in rechargeable polymer batteries. This project focuses on determination of the eutectic phase diagram as a means of suppressing and/or eliminating undesirable constituent crystals in the binary and ternary mixture of polyethylene glycol diacrylate (PEGDA)/succinonitrile (SCN)/lithium bis-(trifluoromethylsufonyl)imide (LiTFSI). The uniqueness of the present system is that photolithographic crosslinking of PEGDA not only affords improved mechanical strength and integrity of the networks, but also increases the ion transport through the unperturbed channels. Moreover, the aligned oriented channel structure will also increase the ion storage capacity due to increase in interface areas and complexation with nitrile groups of SCN. Another advantage is that SCN can effectively ionize the ionic salts and also completely eliminate the undesirable LiTFSI crystals. More importantly, the fabricated polymer electrolyte membrane is a free-standing film that requires no organic solvent and has a high conductivity (7.1x10-3 S/cm) at ambient temperature. The fabricated polymer electrolyte membrane may be operated over a wide temperature range, from 40-80 deg C.NON-TECHNICAL SUMMARY: The goal of this project is to study and develop lightweight and rechargeable free-standing polymer lithium ion batteries for "green" electric vehicles. Unlike conventional electrolyte batteries, the present polymer electrolyte membrane contains no toxic or flammable organic solvent and thus the safety issue such as solvent leakage or battery combustion may be avoided. The present polymer electrolyte is moldable in any shape or form, and thus it should find broader utility. The strategy of the perpendicular alignment of cylindrical columnar morphology along the film thickness direction will further improve ion transport through the channels and enhance ion storage capacity due to increase in surface/interface areas. The knowledge thus acquired can be transferred beyond the scope of the current project, specifically to development of organic materials for solar cells and photo-optical switching in information technology. This project will educate graduate and undergraduate students who will be exposed to multi-disciplinary research in polymer materials science, engineering mathematics, and electrochemistry. The research outcomes will be disseminated to the public through the PI's website or distance-learning programs of the Akron Global Polymer Academy, which conducts workshops for high-school science teachers and their students.

技术摘要：该项目的主要目标是（1）证明对三元相图的基本理解如何为易于制造自由固定的柔性聚合物电池提供指导，以及（2）通过光关节型和定期定期的定期型号和定期的域名统一的等值同源物的统一性阵列来阐明管理原理。这些由光聚合引起的相位分离产生的对齐通道不仅可以用作离子导电线（或微通道），而且还可以增加离子浓度，而无需牺牲自由式电池电池膜的机械强度和完整性。这种具有垂直方向的通道的周期阵列已被高度寻求，以增强电子/激子的运输，以开发有机材料，用于太阳能电池应用以及在可充电聚合物电池中有效的LI+离子传输。该项目的重点是确定共晶相图，作为抑制和/或消除多乙二醇二氯二丙烯酸酯（PEGDA）/琥珀诺硝酸盐/琥珀诺硝酸盐（SCN）/bis-- bis--（trifluoromomomemathylsylsylsylsifone）的二元和三元混合物中的抑制和/或消除不良组成晶体的方法。 当前系统的独特性是，PEGDA的光刻交联不仅提供了网络的机械强度和完整性，而且还可以通过未扰动的通道增加离子传输。此外，由于界面区域的增加和与SCN的硝酸基团的络合，定向的通道结构还将增加离子存储能力。另一个优点是SCN可以有效地将离子盐离子化，也可以完全消除不良的LITFSI晶体。更重要的是，制造的聚合物电解质膜是一部独立的膜，不需要有机溶剂，并且在环境温度下具有高电导率（7.1x10-3 s/cm）。制造的聚合物电解质膜可以在40-80度的宽温度范围内进行操作。与常规电解质电池不同，目前的聚合物电解质膜不含有毒或易燃的有机溶剂，因此可以避免安全问题，例如溶剂泄漏或电池燃烧。 目前的聚合物电解质以任何形式或形式都可塑造，因此应该找到更广泛的效用。 沿膜厚度方向的圆柱柱形态垂直排列的策略将进一步改善通过通道的离子传输并增强由于表面/界面区域的增加而增强离子存储能力。因此获得的知识可以超出当前项目的范围，特别是为了开发用于太阳能电池的有机材料和信息技术中的光电开关。该项目将教育研究生和本科生，他们将接受聚合物材料科学，工程数学和电化学的多学科研究。研究成果将通过PI的网站或Akron Global Polymer Academy的远程学习计划将其传播给公众，该学院为高中科学老师及其学生开展研讨会。