Phosphonated Poly (2,5-Benzimidazole)/Zirconium Phosphate Nanocomposite Membrane for Vanadium Redox Flow Battery Application

The utilization of zirconium phosphate (ZrP) nanoparticle in ABPBI (Poly 2,5 benzimidazole) polymer holds significant promise for the creation of a high-performance, cost-effective ion exchange membrane (IEM) in vanadium redox flow batteries (VRFBs). It has the potential to address the limitations of high-cost and limited ion selectivity associated with Nafion-based ion exchange membranes (IEMs). In this work, the ZrP nanoparticles were synthesized through the reflux method and characterized via X-ray diffraction (XRD), dynamic light scattering (DLS), and scanning electron microscopy (SEM). The ABPBI-ZrP nanocomposite was fabricated using solvent casting, followed by the doping of membranes with phosphoric acid to boost proton conductivity. The physiochemical properties of the membrane were studied, and its mechanical properties were analyzed using a universal testing machine (UTM). The composite membrane achieved an ion exchange capacity of 2.7 mmol/g, proton conductivity of 0.54 mScm−1and a tensile strength up to 57 MPa. The findings clearly show improvements over the ABPBI membrane. These advancements have the potential to significantly enhance the efficiency and effectiveness of VRFBs, offering more dependable and efficient energy storage solutions.