Benzotriazinyl radical containing polymers as bipolar active electrode material in organic secondary batteries

对移动的设备的兴趣日益增长，以及它们日益融入万维网（物联网），使得小型灵活的能量存储系统的可用性和开发成为必要。然而，代表当前基准技术的锂离子电池不允许组装柔性电池，并且需要用于生产和加工原材料以及用于废弃设备的最终处置的环境上有问题的技术。因此，目前的研究越来越多地集中在基于有机氧化还原活性分子的薄膜电池上，所述有机氧化还原活性分子通过有机合成制备并通过燃烧处理而无残留物。此外，它们的（电）化学性质可以通过选择合适的化学结构来容易地调节。不幸的是，小分子倾向于溶解在使用过的电解质中，导致电池的寿命显著降低。因此，单体氧化还原活性单元被整合到具有显著降低的溶解度的长链聚合物中。在该项目的过程中，特别是开发了基于苯并-1，2，4-三嗪基自由基的聚合物。这种分子具有电化学可逆性，对空气和水分的高稳定性，以及易于合成的可及性。此外，其氧化还原特性可以通过分子取代模式容易地调节，这使得甚至能够制备既可以用作阳极材料又可以用作阴极材料的系统，从而允许构建双极，即，e.电池的增加仍然是低理论容量（从约60 mAh g-1增加到超过100 mAh g-1）代表了中心目标，这应该主要通过降低单体的摩尔质量来实现。必须保持（电）化学稳定性、约1.2V的电池电压（以允许水性电解质）和分子的可聚合性，这通过在取代基变化过程中研究结构-性质关系来确保，以实现系统的系统优化。表征过程包括对溶液和固态中的单体和聚合物化合物进行初步表征，将聚合物与导电添加剂和粘合剂材料一起加工成薄膜复合电极及其后续表征，以及组装和全面研究半有机（使用锂或钠作为阳极材料）和全有机电池。此外，电池的制备也得到了优化，特别是在所用添加剂和薄膜加工（刮涂、喷墨印刷）方面。

The growing interest in mobile devices and their increasing integration into the World Wide Web (Internet of Things) necessitates the availability and development of small and flexible energy-storage systems. However, lithium ion batteries, which represent the current benchmark technology, do not allow the assembly of flexible batteries and demand environmentally questionable techniques for production and processing of raw materials as well as for the final disposal of disused devices. Hence, current research focuses more and more on thin film batteries that are based on organic redox active molecules, which are prepared through organic synthesis and disposed free of residues via burning. Furthermore, their (electro)chemical properties can be easily tuned through choosing a suitable chemical structure. Unfortunately, small molecules tend to dissolve in the used electrolyte leading to a significantly decreased lifetime of the battery. Thus, the monomeric redox active units are integrated into long chain polymers, which possess a substantially decreased solubility.In the course of the project, in particular polymers that are based on the benzo-1,2,4-triazinyl radical are developed. This molecule features electrochemical reversibility, high stability against air and moisture, as well as facile synthetic accessibility. Its redox characteristics can be, furthermore, easily tuned through the molecular substitution pattern, which enables even the preparation of systems that can serve both as anode and cathode material, allowing the construction of bipolar, i. e. poleless, batteries.The increase of the batteries still low theoretical capacity (from around 60 to over 100 mAh g-1) represents a central goal, which should be mainly achieved through the reduction of the molar mass of the monomer. (Electro)chemical stability, cell voltages of around 1.2 V (to allow for aqueous electrolytes), and polymerizability of the molecule have to be maintained, which is ensured through the investigation of structure-property relationships in the course of substituent variations to enable a systematic optimization of the system. The characterization process comprises the preliminary characterization of the monomeric and polymeric compounds in solution and in the solid state, the processing of the polymers with conductive additives and binder materials toward thin film composite electrodes and their subsequent characterization, as well as the assembly and comprehensive investigation of half-organic (using lithium or sodium as anode material) and full organic cells. Furthermore, the preparation of the batteries is optimized, in particular with regard to the used additives and the thin-film processing (doctor blading, inkjet printing).