The Effect of Blockages in a PEM Electrolyzers Flow-Field on Performance and Temperature Distribution
The major hurdles facing PEM electrolysis before it can truly and competitively enter commercial markets, is the cost of production and the operational cost of the system. The production costs have been a major focus of research since 2010, and a 41% reduction in cost has been shown at the stack level alone in the past 5 years3. The reduction of operational costs and increase in life expectancy and performance of the stacks also plays a critical role in the overall cost of hydrogen production. Some external factors such as poor water supply quality, hot spots from areas of high contact resistance or uneven loading of the catalyst layer, or even blockages in the flow-fields may limit a PEM electrolysis systems lifetime as well as its performance.
In this article the effect of a blockage, as well as multiple blockages in a parallel flow channel were investigated using a segmented cell capable of reading temperature and current distribution over the entire active area of the test cell. A blockage in the flow-field could arise in an electrolysis cell through a large variety of sources, broken pieces of sealing material, poor water quality, large particles from corroded supply tubing and errors made during assembly. This could cause increases in mass transport losses and increased degradation rates on the rest of the cell. The cells operating parameters were also varied to explore and determine how to mitigate the effects a flow blockage has on cell performance.