What Are Electrolyzers?
Electrolyzers are electrochemical energy conversion devices that use electricity to split water into oxygen and hydrogen, the latter of which can be used for vehicle fueling, fertilizer production and biogas. If electrolyzers are powered with electricity from a renewable or nuclear source, then the hydrogen produced can replace hydrogen from steam methane-reforming.
While industrial electrolyzers do exist, they are too expensive in their current form for widespread adoption and integration into renewable grids or fueling. Our group works to reduce the cost and improve the efficiency of electrolyzers by resolving component-related mass and charge transport limitation using a combination of experimental and modeling tools.
In these efforts, we are focusing on:
- characterizing membrane and ionomer mechanical and chemical properties under liquid water environments and high temperature
- characterizing dispersion and ink properties prior to fabricating catalyst layers and membranes and then characterizing their functional properties post-fabrication;
- catalyst and ionomer interactions within the catalyst layer using microelectrodes;
- the catalyst and transport layer interfaces as well as the transport layers themselves using tomography
Unitized Regenerative Fuel Cells
Unitized regenerative fuel cells (URFCs) are a crosscutting technology that comprises an electrolyzer and fuel cells in one single device, they can be thought of as energy conversion devices with scalable storage with very high energy densities. In these devices, many of the challenges of fuel cells and electrolyzers are combined into one, requiring a unique approach and understanding in addition to integration of knowledge from both sides. Here ECG’s objectives are to characterize and quantify the advantage these devices have while exploiting and exploring various technical solutions in order to improve performance and durability, to show the feasibility of operation in different modes of operation and to be a leader in the state of the art of this technology.
Electrolytic Cells for CO2 Reduction
The electrochemical conversion of CO2 to useful fuels and chemicals like carbon monoxide, methane, methanol, ethylene, and ethanol allows us to use off-peak or intermittent, renewable electricity from photovoltaics and wind as electron sources and effectively achieve carbon neutrality.
In collaboration with the Joint Center for Artificial Photosynthesis (JCAP) and with modelling and diagnostic efforts, we’re investigating, designing, and optimizing this electrolytic cell with gas diffusion electrodes for the selective and efficient production of fuels, specifically focusing on the catalyst layer design.
High Temperature Electrolyzers
Solid oxide electrolysis cells that operate at high temperature (500-800C) provide high performance and efficiency, and can make use of waste heat or steam from industrial or geothermal sources. Converting intermittent renewable resources such as wind and solar is associated with fluctuations in operating temperature and pressure, that stress the cells and stack components. We are developing metal-supported SOEC cells that tolerate extremely rapid temperature fluctuations, handle mechanical abuse, and provide very high performance.