Nanocatalyzed PtNi Alloy Intact @3D Graphite Felt as an Effective Electrode for Super Power Redox Flow Battery
Karuppusamy Mariyappan, Thiyagarajan Mahalakshmi, Thangampillai Senthilkumar Roshni, P. Ragupathy, Mani Ulaganathan
Abstract
Abstract A zinc‐bromine redox flow battery (RFB) is highly suitable for high‐energy storage due to its decoupled energy and power generation. However, the poor kinetics and poor reversible behavior of Br 2 /Br − redox activity are some of the significant barriers, and as a result, the flow system delivers low power density. To increase the efficiency of the flow cell, in the present work, bimetallic catalysts are deposited on 3D graphite felt network and are used in the positive electrode for enhancing the kinetics of the Br 2 /Br − redox reaction. The platinum–nickel (PtNi) bimetallic composition is optimized, and the highly improved performances are investigated using half‐cell and flow‐cell assembly. The redox kinetics parameters are improved due to the high electro‐catalytic nature of the heat‐treated Ni‐rich PtNi coating on the graphite felt (GF) and the flow cell is operated up to 140 mA cm −2 . The flow cell with Pt 0.5 Ni 1 @GF delivers an impressive ever‐best power density of around 1550 mW cm −2 . The cycle life shows excellent stability up to 300 cycles with coulombic, voltage, and energy efficiency of 97%, 86%, and 83%, respectively. Thus, the present work offers a promising approach to developing effective electrode materials for obtaining a superpower RFB system.