Collaborative Research: Next-Generation Simultaneously Ion- and Electron-Conducting Block Copolymer Binders for Battery Electrodes

可充电锂离子电池通过存储风能和太阳能等间歇性可再生能源产生的电力，或为使用可再生能源充电的零排放电动汽车提供动力，有助于实现可持续能源系统。锂离子电池由多种材料组成，用于储存和释放离子、传输电荷和保持机械完整性。粘结材料虽然只占电池重量的不到10%，但却是保持不同材料之间粘合的重要组成部分。这个合作项目将开发一种基于聚合物的新型结合材料，这种材料既导电又具有电化学活性，可以提高机械和电化学性能。科学研究将为锂离子电池电活性聚合物粘结剂的设计奠定基础。关键的创新是聚合物材料将在分子水平上进行设计，以实现这些电活性特性。如果在分子水平上进行适当的设计，这些聚合物有可能提高各种电池电极的稳定性和性能。与此项目相关的教育活动将为社区大学的学生提供开发用于储能的共轭聚合物的机会。此外，还计划通过化学开放日、授权领导联盟、斯伦贝谢能源研究所和莎莉·莱德节，向来自不同和代表性不足群体的K-12学生开展推广活动。在锂离子电池系统中，聚合物粘合剂提供与各种电极组件的粘附，并稳定与电流收集器的接触。然而，目前的粘合剂是电子不活跃的。通过电活性聚合物粘合剂的分子设计，电极性能和容量的实质性改进可能成为可能。为此，需要具有离子导电性、电子导电性、氧化还原活性以及机械稳定性的聚合物粘合剂。这项研究的目标是开发和了解实现这些特性所需的高分子材料的功能。研究计划将考虑包含电子导电骨架、自掺杂和离子电导率侧链以及氧化还原活性羰基的聚合物。研究计划有三个目标。第一个目标是合成同时导电离子和电子的共聚物，并表征其结构、物理化学和电化学性质。第二个目标是表征在第一个目标下开发的含有硅基材料和聚合物粘合剂的杂化阳极的电化学/机械性能。第三个目标是将氧化还原活性基团纳入到聚合物骨架中，并检查它们在导电聚合物粘合剂性能中的作用。通过这种方法，本工作旨在建立影响聚合物材料导电性、机械完整性和电化学活性的基本特性，从而为与各种电极材料兼容的电活性粘合剂的设计规则提出建议。

Rechargeable lithium ion batteries help to enable sustainable energy systems by storing electricity generated by intermittent renewable resources such as wind and solar energy, or by powering zero-emission electric vehicles charged by electricity from renewable resources. Lithium-ion batteries are comprised of a variety of materials for storing and releasing ions, transporting electrical charge, and maintaining mechanical integrity. Binder materials, although representing less than 10% of the battery by weight, are an important component for maintaining adhesion between the different materials. This collaborative project will develop a new class of binding materials based on polymers that are both conductive and electrochemically active, enhancing both mechanical and electrochemical properties. The scientific research will establish the principles for the design of electroactive polymeric binders for lithium ion batteries. The key innovation is that the polymer material will be designed at the molecular level to enable these electroactive properties. When properly designed at the molecular level, these polymers have potential to improve the stability and performance of a wide range of battery electrodes. The educational activities associated with this project will provide opportunities for community college students to work on the development of conjugated polymers for energy storage. Furthermore, outreach activities to K-12 students from diverse and underrepresented groups are planned through Chemistry Open House, Empowering Leadership Alliance, Schlumberger Energy Institute, and the Sally Ride Festival.In lithium ion battery systems, polymeric binders provide adhesion with various electrode components and stabilize contact with the current collector. However, current binders are electronically inactive. Substantial improvements in electrode performance and capacity may be possible through the molecular design of electroactive polymeric binders. Towards this end, polymeric binders that are ion-conducting, electron-conducting, and redox-active as well as mechanically stable, are needed. The goal of this research is to develop and understand the functionality of the polymer materials needed to enable these properties. The research plan will consider polymers that contain electronically conductive backbones, side chains for self-doping and ionic conductivity, and redox-active carbonyl groups. The research plan has three objectives. The first objective is to synthesize co-polymers that conduct both ions and electrons simultaneously, and characterize their resulting structural, physiochemical, and electrochemical properties. The second objective is to characterize the electrochemical/mechanical properties of hybrid anodes containing a silicon base material and polymer binders developed under the first objective. The third objective is to incorporate redox-active groups into the polymer backbone and examine their role on conductive polymer binder properties. Through this approach, this work seeks to establish the fundamental properties that influence conductivity, mechanical integrity, and electrochemical activity of the polymeric materials to suggest design rules for electroactive binders that are compatible with a broad range of electrode materials.