A cost-effective alkaline polysulfide-air redox flow battery enabled by a dual-membrane cell architecture
Yuhua Xia, Mengzheng Ouyang, Vladimir Yufit, Rui Tan, Anna Regoutz, Anqi Wang, Wenjie Mao, Barun Kumar Chakrabarti, Ashkan Kavei, Qilei Song, Anthony Kucernak, Nigel P. Brandon
Abstract
Abstract With the rapid development of renewable energy harvesting technologies, there is a significant demand for long-duration energy storage technologies that can be deployed at grid scale. In this regard, polysulfide-air redox flow batteries demonstrated great potential. However, the crossover of polysulfide is one significant challenge. Here, we report a stable and cost-effective alkaline-based hybrid polysulfide-air redox flow battery where a dual-membrane-structured flow cell design mitigates the sulfur crossover issue. Moreover, combining manganese/carbon catalysed air electrodes with sulfidised Ni foam polysulfide electrodes, the redox flow battery achieves a maximum power density of 5.8 mW cm −2 at 50% state of charge and 55 °C. An average round-trip energy efficiency of 40% is also achieved over 80 cycles at 1 mA cm −2 . Based on the performance reported, techno-economic analyses suggested that energy and power costs of about 2.5 US$/kWh and 1600 US$/kW, respectively, has be achieved for this type of alkaline polysulfide-air redox flow battery, with significant scope for further reduction.