Executive Summary : | Redox flow batteries, such as Zinc Bromine Flow Batteries (ZBFBs), offer promising solutions for the efficient utilization of intermittent renewable energy sources. It utilizes abundant, low-cost materials, high cell voltage (1.84 V), and an energy density of 440 Wh kg-1. However, several challenges hinder practical application, including dendrite formation, electrode corrosion, and seeping of active material which leads to poor coulombic efficiency and shortened lifespan. Furthermore, the limited operating current density and poor electrolyte conductivity pose additional obstacles.
This proposed research aims to address these challenges by engineering the carbon electrode and optimizing the ZnBr2 electrolyte for ZBFBs. The proposed research focuses on fabricating functional electrodes by decorating carbon flakes and metal oxides on graphite felt. These materials possess non-toxicity, excellent electrocatalytic activity, and stability in acidic media, enhancing bromine redox reactions and combating self-discharging and coulombic inefficiency. Conventional electrolytes (ZnBr2) suffer from poor wettability and low conductivity, resulting in increased internal resistance. The proposed strategy involves optimizing the electrolyte composition by incorporating chloride-based additives, improving ionic conductivity and energy efficiency.
scientific Objectives:
* To engineer a functional carbon electrode by decorating carbon flakes and metal oxides on graphite felt, enhancing electrocatalytic activity and bromine redox reactions.
* To optimize the ZnBr2 electrolyte composition by incorporating chloride-based additives to improve wettability and ionic conductivity.
Hypothesis or Model: The modified carbon electrode with decorated flakes and metal oxides will enhance bromine redox reactions, minimizing self-discharging and improving coulombic efficiency. The optimized electrolyte with chloride-based additives will enhance ionic conductivity, reducing internal resistance and improving overall battery performance.
Main Experiments:
Fabrication of functional carbon electrodes: Decoration of carbon flakes and metal oxides (tungsten trioxide, tin oxide) on graphite felt or carbon cloth or paper through controlled methods.
Characterization of electrode performance: Evaluation of electrocatalytic activity, bromine redox reaction kinetics, and stability in acidic media.
Optimization of ZnBr2 electrolyte: Testing different compositions with chloride-based additives and evaluating wettability and ionic conductivity.
Battery performance assessment: Assembling ZBFB cells with modified electrodes and optimized electrolytes, and its electrochemical performance.
significance to the Field: The successful accomplishment of these scientific objectives will exhibit improved efficiency, higher energy density, and longer lifespan, making them a competitive solution for large-scale energy storage systems. |