NETL is collaborating with a team of researchers from UES Services Inc., the University of Connecticut and the Pacific Northwest National Laboratory to explore a novel class of advanced materials called high-entropy alloys (HEAs) that have the potential to overcome long-standing technical barriers for the manufacture of more resilient solid oxide fuel cells (SOFCs).

SOFCs are devices that can chemically convert the energy of a fuel and oxidant directly into electrical energy. Since they produce electricity through an electrochemical reaction and not through a multi-step (e.g., combustion to heat to generator power) process, they are much more efficient and better for the environment than conventional electric power generation processes. These characteristics make SOFCs uniquely valuable to achieving the U.S. Department of Energy’s decarbonization goals.

While SOFCs hold great promise for providing highly efficient, clean energy for a low-carbon economy, current materials have limitations that can often lead to an SOFC wearing out prematurely. This degradation can occur for many reasons, but the research team focused on solving one specific problem related to the manufacture of SOFC anodes.

“The basic structure of an SOFC includes a solid electrolyte positioned between an anode and a cathode,” said Drew O’Connell, NETL federal project manager. “Currently used anode materials can lead to several problems during operation. For example, fuel is delivered to the anode, and if the fuel is carbon-based, the anode is likely to accumulate carbon deposits. These carbon deposits may cause the SOFC to fail.”

The research team, which comprises principal investigators Rabi Bhattacharya of UES Services Inc. (a small business in Dayton, Ohio), Prabhakar Singh, professor at the University of Connecticut and Brian Koeppel of Pacific Northwest National Laboratory, is attempting to mitigate carbon deposits and other problems by developing HEAs to replace those materials typically used for anode manufacture. Unlike typical alloys like steel, in which small amounts of carbon are added to iron to improve its properties, HEAs generally comprise five or more alloys that all contribute significantly to the overall element mix, which results in a more stable structure.

“The HEA created by the team functioned well in the SOFC during testing, and carbon formation was not observed during operation. Also, the HEA anode was shown to have lower reformation rates than traditional nickel-based anodes, which is expected to improve the durability of the SOFC by reducing internal temperature differences that can lead to thermally induced stresses and mechanical failure,” O’Connell said.

This project will wrap up at the end of September, representing a successful partnership in which a viable solution to a real-world problem was identified and advanced. The group has applied for a provisional patent, and SOFC manufacturers have shown interest in using the technology.

“In addition to the benefits this project will bring to fuel cell manufacturing in general, its success also underscores the importance of DOE’s SBIR/STTR programs, which made this important research possible,” O’Connell said.

Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) are U.S. Government programs in which federal agencies with large research and development budgets set aside a small fraction of their funding for competitions among small businesses only. Small businesses that win awards in these programs keep the rights to any technology developed and are encouraged to commercialize the technology.

NETL is a U.S. Department of Energy national laboratory that drives innovation and delivers technological solutions for an environmentally sustainable and prosperous energy future. By leveraging its world-class talent and research facilities, NETL is ensuring affordable, abundant and reliable energy that drives a robust economy and national security, while developing technologies to manage carbon across the full life cycle, enabling environmental sustainability for all Americans.