Executive Summary : | Intermittent nature of the renewable sources is one of the major issues thus; energy needs to be stored at the time of surplus so that it can be made available during the peak hours of demand to overcome the deficit of electricity as well as instability in the grid. Hence, an energy storage system is essential to cater the mismatch in the different time scale. The vanadium redox flow battery (VRB) is well-suited for large-scale utility applications due to its attractive features such as its long life, active thermal management and independence from energy and power ratings, hence VRB is considered as a flexible energy storage option to cater the need of hybrid energy storage system. The VRFB is an electrochemical system that can realize the conversion between chemical energy and electrical energy. As the key part of a VRB, an ion exchange membrane (IEM) is responsible for transferring ions from the anode to cathode as well as for preventing cross mixing of the positive and negative electrolytes. The properties of the IEM greatly affect the resulting performance of the VRFB.The membranes traditionally used are perfluorosulfonic acid polymers such as Dupont’s Nafion. Although it shows both high proton conductivity and chemical stability, the extremely high cost and low ion selectivity of these membranes (high vanadium crossover) have limited their further commercialization in VRFBs. Hence, alternative IEM materials are being sought & highly chemically stable ABPBI-Zirconium phosphate nano composite is studied |