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资源产生的电力，或通过可再生资源充电为零排放电动汽车提供动力，帮助实现可持续能源系统。锂离子电池由多种材料组成，用于存储和释放离子、传输电荷和保持机械完整性。粘结剂材料虽然在电池重量中所占比例不到10%，但却是保持不同材料之间粘附性的重要组件。这一合作项目将开发一种新的基于聚合物的结合材料，这种聚合物既具有导电活性，又具有电化学活性，从而提高机械和电化学性能。这项科学研究将确立锂离子电池电活性聚合物粘结剂的设计原则。关键的创新是，这种聚合物材料将在分子水平上进行设计，以实现这些电活性。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。与该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，通过化学开放参观、赋权领导力联盟、斯伦贝谢能源研究所和Sally Ride音乐节，计划向来自不同和代表性不足群体的K-12学生开展外联活动。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性，并稳定与电流收集器的接触。然而，目前的粘结剂在电子上是不活跃的。通过电活性聚合物粘结剂的分子设计，电极性能和容量的实质性改善是可能的。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性能所需的聚合物材料的功能。该研究计划将考虑含有电子导电主链、用于自掺杂和离子导电性的侧链以及氧化还原活性羰基的聚合物。该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结剂的混合阳极的电化学/机械性能。第三个目标是将氧化还原活性基团结合到聚合物主干中，并研究它们对导电聚合物粘结剂性能的作用。通过这种方法，这项工作试图建立影响聚合物材料的导电性、机械完整性和电化学活性的基本性质，以建议与广泛的电极材料兼容的电活性粘结剂的设计规则。

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.