Containing Hydrogen in a Materials World

Researchers at the Department of Energy’s Pacific Northwest National Laboratory and Sandia National Laboratories have joined forces to reduce costs and improve the reliability of hydrogen fueling stations by identifying materials that won’t break down.

The Hydrogen Materials Compatibility Consortium—or H-Mat—is conducting early-stage research to understand how hydrogen affects the polymers and metals used in infrastructure to store, transport, compress and dispense the fuel. The consortium’s goal is to improve the reliability and durability of materials used in hydrogen infrastructure while also identifying alternative, less expensive materials that reduce equipment replacement cycles and downtime at fueling stations.

The research collaboration includes industry, academia, and three additional national laboratories—Oak Ridge National Laboratory (CSA CSM), Savannah River National Laboratory, and Argonne National Laboratory (CSA CSM). The consortium supports the DOE’s H2@Scale initiative, launched by the Office of Energy Efficiency and Renewable Energy’s Fuel Cell Technologies Office. The focus of H2@Scale is to advance affordable wide-scale hydrogen production, transport, storage and utilization to unlock revenue potential and value across sectors.

The use of hydrogen in fuel cells is growing rapidly for multiple applications, such as forklifts, vehicles—including buses and trucks—and stationary power. Beyond transportation applications, the use of hydrogen can add value in stationary energy storage for the grid and backup power, and for industrial sectors like steel manufacturing and ammonia production.

Partnering in a Materials World
Hydrogen also happens to be a very small and reactive molecule that can cause materials to behave differently than they would in air. These differences mean developers must engineer components such as metal tanks, polymer hoses, and seals that can withstand repeated cycling of materials from high to low pressure. Identifying and developing materials that are more resistant to degradation, such as hydrogen embrittlement in metals or blistering and micro cracking in polymers, will increase component lifetimes and reduce maintenance requirements.

In order to develop better materials, though, the research team must understand how hydrogen interacts with materials. The team, which comprises world-class scientists who have been recognized for their expertise in polymer and steel hydrogen compatibility, will work over a four-year period to enhance durability and lower costs of seals and storage vessels. This research will be relevant to many current and emerging applications, including hydrogen storage, onboard fuel cell vehicles, hydrogen fueling stations, and hydrogen energy storage. The team will develop strategies to select or design improved materials using a combination of advanced computation and unique experimental facilities across the national laboratory system.

The Hydrogen Effects on Materials Laboratory at Sandia is one of a few research facilities in the United States that allows for the mechanics of materials to be studied in high-pressure hydrogen. Sandia is focusing on the metals portion of the study.

PNNL is focused on the polymers portion of the study. PNNL’s Hydrogen Polymers Characterization Laboratory houses unique capabilities for measuring degradation of polymers, including a high-pressure, in-situ dynamic mechanical analyzer to study pressure and gas effects on non-metallic materials and other specialized instruments that measure friction and wear on sealing materials.

“Materials scientists at the two labs are the foundation for the experimental studies within this consortium,” says Kevin Simmons, PNNL senior research scientist who serves as H-Mat co-lead. “We’re also leveraging our labs’ high-performance computational capabilities to model fundamental hydrogen-materials interactions.” Adds Simmons, “The combination of state-of-the-art experimental and computation capabilities at the national labs will provide enhanced understanding of hydrogen gas interactions with polymers and metals.”

Additionally, imaging capabilities and physical metallurgy expertise at Oak Ridge, imaging/testing resources at Savannah River, and chemical analysis capabilities at Argonne will inform the consortium’s research.

The non-proprietary data obtained as part of the H-Mat Consortium is being made publicly available to accelerate national research and development in materials compatibility.