No Cover Image

Journal article 13 views

Minimising the ohmic resistance of an alkaline electrolysis cell through effective cell design / Robert Phillips; Adam Edwards; Bertrand Rome; Daniel R. Jones; Charles W. Dunnill

International Journal of Hydrogen Energy

Swansea University Author: Dunnill, Charlie

  • Accepted Manuscript under embargo until: 14th August 2018

Abstract

The efficiency of an alkaline electrolysis cell depends strongly on its internal cell resistance, which becomes the dominant efficiency driver at high current densities. This paper uses Electrochemical Impedance Spectroscopy to decouple the ohmic resistance from the cell voltage, and, for the first...

Full description

Published in: International Journal of Hydrogen Energy
ISSN: 0360-3199
Published: 2017
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa34946
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: The efficiency of an alkaline electrolysis cell depends strongly on its internal cell resistance, which becomes the dominant efficiency driver at high current densities. This paper uses Electrochemical Impedance Spectroscopy to decouple the ohmic resistance from the cell voltage, and, for the first time, quantify the reduction in cell resistance achieved by employing a zero gap cell configuration when compared to the conventional approach. A 30% reduction in ohmic resistance is demonstrated for the zero gap cell when compared to a more conventional design with a 2 mm electrode gap (in 1 M NaOH and at standard conditions). The effect on the ohmic resistance of operating parameters, including current density and temperature, is quantified; the zero gap cell outperforms the standard cell at all current densities, particularly above 500 mA·cm−2 Furthermore, the effect of electrode morphology on the ohmic resistance is investigated, showing that high surface area foam electrodes permit a lower ohmic resistance than coarser mesh electrodes. These results show that zero gap cell design will allow both low cost and highly efficient alkaline electrolysis, which will become a key technology for short term and inter-seasonal energy storage and accelerate the transition towards a decarbonised society.
Keywords: Alkaline electrolysis; Electrochemical impedance spectroscopy; Zero gap; Porous electrodes; Renewable energy storage
College: College of Engineering