TY - JOUR
T1 - Resistance Breakdown of a Membraneless Hydrogen-Bromine Redox Flow Battery
AU - Alfisi, Daniel
AU - Shocron, Amit N.
AU - Gloukhovski, Robert
AU - Vermaas, David A.
AU - Suss, Matthew E.
PY - 2022
Y1 - 2022
N2 - A key bottleneck to society's transition to renewable energy is the lack of cost-effective energy storage systems. Hydrogen-bromine redox flow batteries are seen as a promising solution, due to the use of low-cost reactants and highly conductive electrolytes, but market penetration is prevented due to high capital costs, for example due to costly membranes to prevent bromine crossover. Membraneless hydrogen-bromine cells relying on colaminar flows have thus been investigated, showing high power density nearing 1 W/cm2. However, no detailed breakdown of resistance losses has been performed to-date, a knowledge gap which impedes further progress. Here, we characterize such a battery, showing the main sources of loss are the porous cathode, due to both Faradaic and Ohmic losses, followed by Ohmic losses in the electrolyte channel, with all other sources relatively minor contributors. We further develop and fit analytical expressions for the impedance of porous electrodes in high power density electrochemical cells to impedance measurements from our battery, which enabled the detailed cell resistance breakdown and determination of important electrode parameters such as volumetric exchange current density and specific capacitance. The insights developed here will enable improved engineering designs to unlock exceptionally high-power density membraneless flow batteries.
AB - A key bottleneck to society's transition to renewable energy is the lack of cost-effective energy storage systems. Hydrogen-bromine redox flow batteries are seen as a promising solution, due to the use of low-cost reactants and highly conductive electrolytes, but market penetration is prevented due to high capital costs, for example due to costly membranes to prevent bromine crossover. Membraneless hydrogen-bromine cells relying on colaminar flows have thus been investigated, showing high power density nearing 1 W/cm2. However, no detailed breakdown of resistance losses has been performed to-date, a knowledge gap which impedes further progress. Here, we characterize such a battery, showing the main sources of loss are the porous cathode, due to both Faradaic and Ohmic losses, followed by Ohmic losses in the electrolyte channel, with all other sources relatively minor contributors. We further develop and fit analytical expressions for the impedance of porous electrodes in high power density electrochemical cells to impedance measurements from our battery, which enabled the detailed cell resistance breakdown and determination of important electrode parameters such as volumetric exchange current density and specific capacitance. The insights developed here will enable improved engineering designs to unlock exceptionally high-power density membraneless flow batteries.
KW - Electrical Grid
KW - Electrochemical Impedance Spectroscopy
KW - Energy Storage
KW - Hydrogen-Bromine Battery
KW - Redox Flow Batteries
UR - http://www.scopus.com/inward/record.url?scp=85139414429&partnerID=8YFLogxK
U2 - 10.1021/acssuschemeng.2c02169
DO - 10.1021/acssuschemeng.2c02169
M3 - Article
AN - SCOPUS:85139414429
SN - 2168-0485
VL - 10
SP - 12985
EP - 12992
JO - ACS Sustainable Chemistry and Engineering
JF - ACS Sustainable Chemistry and Engineering
IS - 39
ER -