STTR Phase I: Hydrogen Bromine Electrolysis for Highly Efficient Hydrogen-Based Energy Storage and High Value Chemical Applications

该项目更广泛的影响/商业潜力包括从高峰负荷转移、可再生能源输入的电网缓冲、频率调节和化学转换等应用。随着可再生能源在电网中所占比例的增加，储能将成为稳定供需的关键。目前，由于无法在发电高峰期捕获能量，20%-40%的风能经常搁浅。德国、欧洲、日本、韩国和其他国家正在为能源储存项目提供大量资金。能量储存也是美国所有武装部队的一项关键需求，包括前方行动基地的微电网和其他离网设施。虽然电池可以表现出非常好的往返效率，但它们存在自放电、容量衰减和成本高的问题。液流电池将反应物和产品存储与电极有源区分开，只需增加存储空间即可实现更高的容量。由于能量密度值低，许多系统在过去并不实用，但燃料电池和电解的发展提供了获得更高能量密度的途径。这些领域的进展将带来直接的商业利益，并解决与能源安全和电网稳定相关的关键战略领域。这个小型企业技术转移第一阶段项目解决了液流电池电池组设计方面的现有技术差距，以实现可靠、高效、高倍率的氢溴液流电池，用于储能应用。该项目的目标是验证概念溴化氢电堆在电解模式下以实际储氢压力运行，同时在燃料电池模式下提供可接受的能量密度。到目前为止，大多数氢溴液流电池的研究都集中在放电反应上，导致材料的选择可能不适合充电模式。该项目将证明在实际储存压力下密封和支撑薄膜的可行性。目标包括用能够支持高功率燃料电池模式的材料演示差压电解，确定溴/溴的交叉率作为氢背压的函数，以及探索用于全流量电池系统的兼容材料。除了第一阶段资助的工作，计划中的研究将包括电池组设计优化，向下选择合适的材料，以及充电电池循环的原型系统开发。预期的结果将是一个高效的液流电池系统，在充电模式下具有耐用性，在放电模式下具有高功率密度，以实现具有成本效益的能量存储系统。

The broader impact/commercial potential of this project includes applications ranging from peak load shifting, grid buffering for renewable energy input, frequency regulation, and chemical conversions. As the percentage of energy from renewables on the grid increases, energy storage will be essential to stabilize the supply and demand. Currently, 20-40% of wind energy is often stranded due to the inability to capture the energy in the peak generation periods. Germany, Europe, Japan, Korea, and other countries are funding significant efforts in energy storage projects. Energy storage is also a critical need for all of the United States armed services, including microgrids for forward operating bases and other off grid installations. While batteries can demonstrate very good round trip efficiencies, they suffer from self-discharge, capacity fade, and high cost. Flow batteries separate the reactant and product storage from the electrode active area, enabling higher capacities through merely adding more storage. Many systems have not been practical in the past due to low energy density values, but fuel cell and electrolysis developments have provided pathways to higher energy density. Advances in these areas would find immediate commercial interest, and address key strategic areas related to energy security and grid stabilization. This Small Business Technology Transfer Phase I project addresses the present technology gaps in flow battery cell stack design to enable a reliable, efficient, high rate hydrogen-bromine flow battery for energy storage applications. The goal of this project is a proof of concept hydrogen bromide stack that operates at a practical hydrogen storage pressure in electrolysis mode, while providing acceptable energy density in fuel cell mode. The majority of hydrogen bromine flow battery research to date has focused on the discharge reaction, leading to material choices that may not be practical for the charging mode. This project will demonstrate feasibility of sealing and supporting thin membranes to practical storage pressures. Objectives include demonstration of differential pressure electrolysis with materials that can support high power fuel cell mode, determining the bromine/bromide crossover rates as a function of hydrogen back pressure, and exploring compatible materials for the full flow battery system. Going beyond the Phase I funded effort, research being planned will include cell stack design optimization, down-selection of appropriate materials, and prototype system development for charge battery cycling. The anticipated result will be a highly efficient flow battery system with durability in charge mode and high power density in discharge mode for a cost effective energy storage system.