Zwitterionic polymer-based electrolyte engineering for alkali metal ion batteries

用于碱金属离子电池的两性离子聚合物电解质工程

• 批准号: 2217188
• 负责人: Matthew Panzer
• 金额: $ 34.91万
• 依托单位: Tufts University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2217188&HistoricalAwards=false
• 关键词: Zwitterionic; polymer; based; electrolyte; engineering

Lithium-ion batteries are ubiquitous in modern society, powering everything from wearable/handheld devices to electric vehicles. Securing the future of reliable and cost-effective electrochemical energy storage, however, will depend on using a variety of battery chemistries, including those that utilize more abundant alkali metal ions such as sodium. For every battery that is developed, maximizing the motion of certain target ions and ensuring a high degree of user safety are two critically important goals. In this project, the investigators will examine the ability of a class of highly stable polymers featuring zwitterionic side groups to promote increased selective transport of sodium and lithium cations. Zwitterions are a class of molecules which contain both a positive and a negative charge. Moderate amounts of a nonflammable, room temperature molten salt (an ionic liquid) will be co-formulated in these electrolytes to enhance overall ionic motion while maintaining safe operation. This study will produce important new insights into the roles of zwitterion chemistry, ionic liquid content, and alkali metal cation identity in determining ideal chemical compositions for future battery electrolytes. Through mentored undergraduate and graduate research experiences for underrepresented students and participation in K-12 outreach activities, this project will also benefit society by enabling transformative educational and training experiences for a diverse group of students at multiple experience levels.The main objective of this project is to examine the intermolecular interactions and selective alkali metal cation (lithium, sodium) transport within zwitterionic polymer/salt electrolytes that contain ionic liquid (IL) mass fractions of approximately 5-80 wt.%. This is an underexplored compositional space that exists between conventional polymer electrolytes and IL-rich ionogels. The research objectives will be accomplished by pursuing multiple synthetic strategies to prepare such electrolytes, probing interactions between the various charged species using several multinuclear NMR and FTIR/Raman spectroscopy techniques, measuring total ionic conductivities and alkali metal cation transference number values via AC impedance spectroscopy and DC polarization tests, and interrogating electrochemical stability upon repeated strip-plate cycling in symmetric alkali metal electrode cells. It is hypothesized that high-mobility pathways for alkali metal cation transport may be created along the pendant zwitterionic functional groups on the polymer, which provides a motivation for examining the effects of reducing the IL content among this novel class of electrolytes. This project will be among the first to directly compare sodium versus lithium cation transport using different zwitterionic polymer chemistries, which will provide useful information for the future design of polymer-based electrolytes for “beyond-Li ion” batteries.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

锂离子电池在现代社会中无处不在，为从可穿戴/手持设备到电动汽车的各种设备提供动力，然而，确保可靠且经济高效的电化学能源存储的未来将取决于使用各种电池化学物质，包括那些利用的化学物质。对于每一种开发的电池，最大化某些目标离子的运动和确保高度的用户安全是该项目中的两个至关重要的目标，研究人员将检查其能力。一类具有两性离子侧基的高度稳定的聚合物，可促进钠和锂阳离子的选择性传输。两性离子是一类同时含有正电荷和负电荷的分子。离子液体）将在这些电解质中共同配制，以增强整体离子运动，同时保持安全运行。这项研究将对两性离子化学、离子液体含量和离子液体的作用产生重要的新见解。通过为代表性不足的学生提供指导的本科生和研究生研究经验以及参与 K-12 外展活动，该项目还将通过为多元化群体提供变革性的教育和培训体验来造福社会。该项目的主要目标是研究含有离子液体的两性离子聚合物/盐电解质中的分子间相互作用和选择性碱金属阳离子（锂、钠）传输(IL) 质量分数约为 5-80 wt.% 这是传统聚合物电解质和富含 IL 的离子凝胶之间存在的尚未充分探索的组成空间。研究目标将通过采用多种合成策略来制备此类电解质、探测相互作用来实现。使用多种多核 NMR 和 FTIR/拉曼光谱技术在各种带电物质之间进行分析，通过交流阻抗谱和直流测量总离子电导率和碱金属阳离子迁移数值极化测试，以及在对称碱金属电极电池中重复剥离板循环时的电化学稳定性的研究重新认识到，碱金属阳离子传输的高迁移率路径可以沿着聚合物上的两性离子官能团产生，这提供了动力。为了研究降低此类新型电解质中离子液体含量的影响，该项目将是第一个使用不同两性离子聚合物化学物质直接比较钠与锂阳离子传输的项目之一。这将为“超越锂离子”电池的聚合物电解质的未来设计提供有用的信息。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。