Hydrogen Bromine Laminar Flow Electrochemical Cell for High Power and Efficiency Energy Storage Applications

Abstract

We present a model for a novel fuel cell system incorporating hydrogen bromine electrochemistry into a laminar flow fuel cell architecture. The proposed system integrates the fast reaction kinetics of the bromine reduction reaction into a membrane-less device that relies on the fluid mechanics of laminar flow to maintain reactant separation. This design eliminates both the cross over losses and the hydration requirements that have limited the effectiveness of many previous proton exchange membrane-based hydrogen bromine fuel cells. A two dimensional model of the system predicts that the hydrogen bromine system will produce 1 W/cm2 at 90% efficiency, with a peak power output of 3.4 W/cm2.

Mathematical modelling of a membrane-less redox flow battery based on immiscible electrolytes

“…Changes in the standard rate constant K 0 appearing in the Butler-Volmer equation (12) through the exchange current…”

“…Unlike previous modelling effort s of membrane-less RFBs that either used a prescribed velocity profile for the electrolytes [12][13][14] or considered only one fluid phase [15,16] , the model presented here includes for the first time a full analysis of both the fluid dynamical and electrochemical aspects of a membrane-less RFB with immiscible electrolytes. To this end, we assume the limit of very dilute solutions in order to decouple the calculation of the flow field from the electrochemical problem that determines the species concentration field.…”

Membrane-less hydrogen bromine flow battery

“…A two-dimensional numerical model of the device was constructed to allow for a greater understanding of the underlying physics of the cell [31,32]. The model solves the Nernst-Planck equations with advection in the imposed flow for the concentrations and electrostatic potential, assuming a quasi-neutral bulk electrolyte.…”

“…A scaled, dimensionless model was constructed in COMSOL Multiphysics, and results were calculated over a range of flow rates and reactant concentrations. A complete description of the model has been presented previously [31,32]. Bromine concentration varied along the length of the channel, resulting in strong spatial variations in the current density (fig.…”

A 1D Mathematical Model of a H2/Br2Fuel Cell

“…Braff and Buie predicted the performance of a novel H 2 -Br 2 laminar flow cell operating under dominant convective transport regime using a two-dimensional mathematical model. 15 This design was employed to reduce cross-over losses and to eliminate the need for a membrane. Recently, Cho et al developed a two-dimensional model to study the impact of flow-by (operated under dominant diffusive transport) and flow-through (operated under dominant convective transport) modes on the performance of their liquid phase H 2 -Br 2 fuel cell.…”