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

这个I-Corps项目的更广泛影响/商业潜力涉及增加对太阳能和风能等可再生能源的利用。由于这些能源的间歇性，储能系统必须连接到我们的电网中，以增加数量，以帮助稳定电网，通过在高峰生产期间储存能量和在高峰消费期间释放能量。该技术由稳定的碳基材料组成，可以长时间储存电荷。这些材料可以用于生产有机电解质电池，特别是称为氧化还原液流电池，它可以在更高的功率密度下充电，并且比目前的水基电池具有更高的能量容量。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，延长电池的使用寿命，并在因充电到过高电位而导致的滥用条件下防止灾难性故障。然而，另一种可能性是使用这些材料来引发化学反应，从而通过消除金属配合物来降低聚合物涂层的制备成本。这个I-Corps项目涉及探索稳定的、供电子的吩噻嗪衍生物的潜在市场，作为储能应用和聚合引发剂的潜在材料。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融合环杂环有机化合物，从而确定了在多种氧化状态（中性，自由基阳离子和阳离子）下具有更大稳定性的特性。最稳定的衍生物被测试为氧化还原穿梭添加剂，用于限制过充电锂离子电池的电压，并且由于其高稳定性，在含有商用电极材料的电池中具有广泛的性能。高溶解度导致它们在高浓度下并入电池电解质，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阴极的研究表明，在高浓度和高充电电流的对称电池中，这些材料的寿命很长。事实上，在许多情况下，高稳定性使它们能够作为结晶自由基阳离子盐被隔离。此外，这些材料已被证明可以在可见光下引发阳离子聚合，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.