High power Vanadium redox flow battery based on Bismuth-tungsten oxide modified carbon felt negative electrode

Vanadium redox flow batteries (VRFB) are considered a prominent alternative to largescaleenergy storage because of their outstanding features compared to other energy storagetechnologies (i.e. Lithium ion batteries) such as longer lifetime (10,000 cycles) [1], flexibledesign, and minimum self-discharge. However, despite of their maturity, cost reduction is themajor challenge to overcome in order to achieve VRFB widespread applications, includingrenewable integration, smart grid uses and off-grid electrification areas [2]. In this work Bi2WO6modified felt was prepared using a 2-step simple hydrothermal method. Many characterizationtechnics such as FE-SEM, EDS, XRD, XPS, Raman, and FT-IR were used to investigateelectrocatalyst materials. EIS, CV, Charge/discharge and cycling tests were used to evaluate cellperformance. The Vanadium/acid electrolyte concentration was optimized and then optimizedparameters were used to run single cell experiments in presence of treated and electrocatalystmodified carbon felt electrodes. Bi2WO6 modified felt was used as negative electrode. Figuresbelow represent SEM of Bi2WO6-CF and a charge/discharge of single cell using Bi2WO6modified carbon felt electrode.

Keywords:

Vanadium Redox Flow Batteries , Tungsten Oxide , N-Doping , Electrolyte Optimization , Bi2WO6