With the wide deployment of renewable energy harvesting devices, such as solar cells and wind turbines, there is an urgency to develop efficient and economical energy storage systems to stabilize the intermittent and often unpredictable primary power sources before the power can be channeled to the grid safely or utilized for on-site loads. Redox flow batteries (RFBs) are regarded as promising electrochemical energy storage devices due to their special features of separable energy and power capacity. However, redox flow batteries tend to have lower energy densities than integrated cell architectures. Here our inventions introduce the novel engineering design to and reduce bulk resistance with no significant increase in flow resistance, obtaining uniform flow throughout the battery cell and improving the overall system efficiency.
This invention provides a novel flow frame design for flow battery cell stacks to reduce internal ohmic resistance. The new design provides a uniform flow field, low contact resistance and helps to strengthen the frame structure during cell stack assembly. Features of this technology are: Extra flexibility to optimize the system performance and minimize shunt current; Convenient to adjust the length of the flow channels on the manifold sets according to specific operating conditions; Easily assembly compared to industry product; Reduce bulk resistance with no significant increase in flow resistance; More uniform electrolyte flow paths to improve the overall system efficiency.
The invented redox flow battery stack can be operated in different electrochemical cell systems, such as all vanadium, vanadium/bromine, iron/chromium, bromine/polysulfide, lithium battery, depending on the electrolytes supplied to the first and second active reaction compartments. Some of the potential applications are: Energy storage applications from renewable energy sources Uninterruptible power supply (UPS) applications Independent power applications
The customer benefits of this novel flow frame design for redox flow battery includes better stack performance, low maintenance cost, robust sealing, and a simplified assembly process. Due to these advantages, the energy efficiency and cost-effectiveness of the newly designed system can be remarkably improved.