رسائل ماجيستير
English
2024
Enhancing Catalytic Activity and Stability of Carbon-Based Electrodes for Vanadium Redox Flow Batteries
Abdulmonem Mohamed Fetyan, Mohamed Adel Allam Mohamed, Mohammad Ali Abdelkareem
كلية الهندسة-جامعة الشارقة · الامارات
Vanadium Redox Flow Batteries (VRFBs) show potential for storing renewable energy, but their
inefficiency hinders their broad adoption in energy utilization. This obstacle arises from the
insufficient catalytic performance of traditional carbon-based electrodes. Graphite felt (GF) is
extensively utilized as an electrode in VRFBs. Nevertheless, its poor reversibility and low
electrochemical activity limit its widespread adoption in large-scale VRFB applications. Our
research uses novel, eco-friendly approaches to enhance VRFB electrode performance.
In the initial method, cost-effective and highly conductive carbon black (CB) is integrated as a
catalyst onto the graphite felt using a deposition technique facilitated by the binder polymer poly
(acrylic acid) (PAA). Subsequently, a high-temperature thermal treatment is applied to activate the
felt and degrade the PAA binder, thereby diminishing ohmic resistance. In a secondary strategy,
we investigate sustainability and recycling by employing discarded cloth, particularly unused
cotton fabric, as electrodes for VRFBs. Biomass-derived carbonized wasted cloth (CWC)
electrodes are produced via a straightforward carbonization procedure, eliminating the necessity
for post-activation typically required with commercial graphite felts. Characterization of these
electrodes reveals significant inter-fiber linkages, thereby decreasing ohmic resistance and
improving charge transfer.
Galvanostatic charge-discharge profiles reveal a notable enhancement in energy efficiencies,
ranging from 10-15% higher compared to thermally treated felts for both carbon-coated felt (CBGF)
and carbonized wasted cloth (CWC) electrodes. There are no signs of degradation after sixty
cycles for either material. This significant improvement in energy efficiency signifies a promising
advancement in VRFB technology, showcasing its potential for large-scale applications and
contributing to enhanced sustainability in energy storage systems.