I-Corps: Electron-Donating Phenothiazines for Non-Aqueous Redox Flow Batteries

这个I-Corps项目的更广泛影响/商业潜力涉及增加利用太阳能和风能等可再生能源。由于这些电源的不稳定性，储能系统必须以更大的数量连接到我们的电网，以通过在高峰生产时间存储能量和在高峰消费期间释放能量来帮助稳定电网。该技术由稳定的碳基材料组成，可以长时间储存电荷。这些材料可以允许生产具有有机电解质的电池，具体地称为氧化还原液流电池，其可以在更高的功率密度下充电，并且具有比当前水基对应物更高的能量容量。除了固定能量存储之外，这些材料还可以作为锂离子电池的添加剂，可以延长寿命，并通过在将电池充电到过高电位的滥用条件下提供保护来防止灾难性故障。另一种可能性是使用这些材料来引发化学反应，从而通过消除金属络合物来降低聚合物涂层的制备成本。I-Corps的这个项目涉及探索稳定的、供电子的吩噻嗪衍生物作为储能应用和聚合引发剂的潜在材料的潜在市场。这些材料的开发是由于研究了各种具有不同取代基身份和位置的稠环杂环有机化合物，这导致了在多种氧化状态（中性，自由基阳离子和二价阳离子）下具有更高稳定性的特征的鉴定。最稳定的衍生物作为氧化还原穿梭添加剂进行了测试，这些添加剂限制了锂离子电池的过充电电压，并且发现由于其高稳定性，在含有商业上使用的电极材料的电池中具有广泛的性能。 高溶解度导致它们以高浓度掺入电池电解质中，从而实现高速率过充电保护。最近，对这些材料作为非水氧化还原液流电池的阴极电解液的研究表明，在高浓度和高充电电流下，对称电池的寿命很长。事实上，在许多情况下，高稳定性允许它们作为结晶自由基-阳离子盐分离。此外，这些材料已显示出使用可见光引发阳离子聚合，这可能导致它们用作光氧化还原催化剂。

The broader impact/commercial potential of this I-Corps project involves enabling increased utilization of renewable energy power sources such as solar and wind. Due to the intermittency of these power sources, energy storage systems must be connected to our electrical grid in increased amounts to help stabilize the grid through storage of energy during peak production times and release of energy during peak consumption. The technology developed consists of stable carbon-based materials that can store charge for extended periods of time. These materials may allow for the production of batteries with organic electrolytes, specifically called redox flow batteries, which can be charged at higher power densities and have higher energy capacities than current aqueous-based counterparts. In addition to stationary energy storage, these materials could serve as additives in lithium-ion batteries that can extend lifetimes and prevent catastrophic failure through protection during abusive conditions that result from charging batteries to too-high potentials. Yet another possibility is to use these materials to initiate chemical reactions that allow for lower-cost preparation of polymer coatings through the elimination of metal complexes.This I-Corps project involves the exploration of potential markets for stable, electron-donating phenothiazine derivatives as potential materials for energy-storage applications and polymerization initiators. These materials were developed as a result of studying a variety of fused-ring heterocyclic organic compounds with varying substituent identity and position, which led to identification of characteristics that led to greater stability in multiple states of oxidation (neutral, radical cation, and dication). The most stable derivatives were tested as redox shuttle additives that limit voltage in overcharging lithium-ion batteries and were found to have extensive performance in batteries containing commercially utilized electrode materials due to their high stability. High solubility led to their incorporation into battery electrolytes at high concentrations, which allowed for high-rate overcharge protection. More recently, the study of these materials as catholytes for non-aqueous redox flow batteries showed extensive lifetimes in symmetric cells at high concentrations and with high charging currents. In fact, in many cases, high stability has allowed for their isolation as crystalline radical-cation salts. Furthermore, these materials have been shown to initiate cationic polymerizations using visible light, which may lead to their use as photo-redox catalysts.