Collaborative Research: Thermodynamics and Ion Transport in Block Copolymer/Lithium Salt Mixtures

技术概述：提出了一项关于嵌段共聚物和锂盐混合物中有序形态、晶粒结构和离子电导率之间相互作用的基础研究。所提出的工作结果有可能影响固体电解质高比能电池的发展。这项工作将侧重于由阴离子聚合合成的聚苯乙烯-聚乙烯氧化物嵌段共聚物和双三氟甲基磺酰亚胺（LiTFSI）的混合物，这种盐通常用于含有聚合物电解质的电池。小角x射线散射和去偏振光散射将用于确定这些材料中有序-无序和有序-有序相变的性质。电导率测量将在与使用交流阻抗光谱进行x射线和光散射研究中使用的样品相同的样品上进行。测量将在广泛的嵌段共聚物组成，盐浓度，温度和退火条件。非技术总结：本项目提出的基础工作的动机是需要为清洁能源相关应用（如电动汽车和固定能源存储）设计安全的可充电电池。所提出的纳米结构离子导电固体将用作锂电池的电解质。用固体电解质代替目前锂电池中使用的易燃液体电解质，可以使用更高能量的电极，从而提高电池的能量密度。没有可燃成分，使电池安全。合作项目将在高中学生参与的推广活动中使用固态电池进行示范。Garetz与纽约市的David Packard技术和教育联盟中心合作，在与技术和研究相关的领域指导当地的高中生。Balsara与伯克利的数学和科学暑期学院项目合作，以及将奥克兰学区的学生带到加州大学的丰富项目。pi将继续与波兰A. Mickiewicz大学的M. Banaszak教授就含离子聚合物的主题进行合作，该主题源于波兰国家科学基金会赞助的研讨会。

TECHNICAL SUMMARY:A fundamental study of the interplay between ordered morphology, grain structure, and ionic conductivity in mixtures of block copolymers and lithium salts is proposed. The results of the proposed work have the potential to impact the development of high specific energy batteries with solid electrolytes. The work will focus on mixtures of polystyrene-polyethyleneoxide block copolymers, synthesized by anionic polymerization, and bis-trifluoromethylsulfonimide (LiTFSI), a salt that is often used in batteries containing polymer electrolytes. Small-angle X-ray scattering and depolarized light scattering will be used to determine the nature of the order-disorder and order-order phase transitions in these materials. Conductivity measurements will be made on the same samples as those used in the X-ray and light scattering studies using AC impedance spectroscopy. Measurements will be made over a wide range of block copolymer compositions, salt concentration, temperature, and annealing conditions. NON-TECHNICAL SUMMARY:The fundamental work proposed in this project is motivated by the need to design safe rechargeable batteries for clean energy-related applications such as electric vehicles and stationary energy storage. The proposed nanostructured ion-conducting solid will be used as the electrolyte in a lithium battery. By replacing the flammable liquid electrolyte that is used in current lithium batteries by a solid, one can use higher energy electrodes that, in turn increase the energy density of the battery. The absence of a flammable component makes the battery safe. The co-PIs will use solid-state batteries for demonstrations in their outreach activities involving high school students. Garetz works with the David Packard Center for Technology and Educational Alliances in New York City to mentor local high school students in fields related to technology and research. Balsara works with Math and Science Summer Academy program at Berkeley, and enrichment program which brings students from the Oakland School District to the University of California. The PIs will continue an ongoing collaboration with Professor M. Banaszak at A. Mickiewicz University, Poland on the subject of ion-containing polymers that arose from an NSF-sponsored workshop in Poland.