A Study Of Hydrogen/bromine Flow Battery

In order to solve the problem of renewable energy on instability and discontinuity in the process of power generation and transportation, more large-scale energy storage technology is becoming more and more popular. Hydrogen/Bromine regenerative fuel cell is one of the most competitively technology for large-scale electrical energy storage for its nature of low cost, high energy density and high energy efficiency. This dissertation justly focuses on Hydrogen/Bromine battery structure and conditions.This paper presents a new battery structure of Hydrogen/Bromine battery. Through this design improves the energy efficiency and durability of Hydrogen/Bromine battery. Through the constant current charging discharging and polarization experiments, studies the performance of single, 5 stack and 45 stack Hydrogen/Bromine. The experimental results show that:For the Hydrogen/Bromine battery, using carbon felt loading 50% Pt/C catalyst(1.0mg/cm2, the anode), carbon paper and Nafion membrane loading 50% Pt/C catalyst(0.2mg/cm2, the negative electrode) as cell structure. The Hydrogen/Bromine battery can be used for 200mA/cm2 current density charging and discharging. Increasing the concentration of HBr electrolytic, the battery has the higher energy efficiency. The energy efficiency reaches 78.77% using 2mol/L HBr electrolytic, in 200mA/cm2 current density.Adding bromine in HBr electrolytic, with the increase of the concentration of bromine,improve the energy efficiency of the battery. The energy efficiency reach 78.43% using2mol/L HBr, 0.4 mol/L Br2 electrolytic, in 200mA/cm2 current density. Reduce the hydrogen pressure in the process of charging to improving battery efficiency. At the discharging hydrogen pressure of 40 KPa, the charging hydrogen pressure of 0KPa, energy efficiency reaches 79.96%. Maintaining the hydrogen pressure during charging for 0KPa, energy efficiency of battery reach 80.02%.Hydrogen/Bromine single battery operates for 54 hours in 2mol/L HBr and 0.4mol/L Br2 electrolytic under 200mA/cm2. Battery performance maintain stable, the highest energy efficiency reaches 80.02%. 5 Hydrogen/Bromine stack is assembled, testing constant current charging and discharging under the current density of 200mA/cm2. The energy efficiency of stack is between 81.03% and 80.42%. 45 Hydrogen/Bromine stack is assembled, operates for500 hours under the current density of 200mA/cm2. The power reaches kilowatt level in the process of discharging, energy efficiency of battery reach 80.06%.