Redox-active polymers as promising electrodes for rechargeable lithium batteries

• Main Author: Xie, Jian
• Other Authors: Zhang Qichun
• Format: Theses and Dissertations
• Language: English
• Published: 2018
• Subjects: DRNTU::Engineering::Materials
• Online Access: https://hdl.handle.net/10356/102657; http://hdl.handle.net/10220/46523
• Institution: Nanyang Technological University

Electrode materials play a critical role in achieving high energy density and long cycle life rechargeable lithium batteries. The increasing concern with respect to the use of traditional inorganic electrode materials on resources and environmental issues has strongly inspired scientists to search green energy electrodes. Organic compounds are potentially sustainable and renewable materials as many of them can be obtained from natural products and biomass. To meet the ever-growing demands for the next generation versatile and sustainable energy-related devices, redox-active polymers, which have potential advantages over inorganic materials, are among the most promising types of green candidates. The properties of redox-active polymers can be tuned through the modification of the structure and incorporation of different functional moieties. The purpose of this project is to develop novel redox-active polymers, which could be potential high-performance electrode materials for organic based rechargeable batteries. Therefore, this thesis mainly addresses the design, synthesis, characterization and electrochemical performance of several novel redox-active polymers and large aromatic molecules for lithium related rechargeable batteries. In detail, an overall introduction for the research on redox-active polymers is provided. The rationale, hypothesis and objectives are involved. Moreover, the strategies, methods and approaches to achieve the objectives are discussed in each chapter. The literature concerning redox-active polymers, background and current situation are also included. Specifically, the history, principles and mechanisms of redox-active polymers are reviewed. Different types of redox-active polymers are classified. The working principles that the characterization techniques employed in this project are introduced. More importantly, this thesis includes the major findings and conclusions: Firstly, two novel redox-active ladderized conjugated polymers and their nanostructures were designed and developed as high-performance negative electrode materials for Li-organic batteries. Secondly, four novel redox-active carbonyl compounds were designed and developed as high-performance positive electrode materials for Li-organic batteries. Thirdly, a novel all-plastic-electrode battery was designed, optimized and developed on the basis of a novel designed bi-functional poly(quinone) electrode. The symmetric full battery delivers excellent electrochemical results. Lastly, a general summary of the whole project is also provided. The recommended future works to obtain advanced flexible battery systems are also introduced in the last chapter.