TECHNOLOGY/BUSINESS OPPORTUNITY Conductive framework impregnated with hydrophobic porous foam for use in electrochemical systems

Background: In general, a gas diffusion electrode (GDE) must be conductive, porous, and hydrophobic so that it allows the passage of gas but not liquid. The established methodology for making GDEs involves coating a pre-existing hydrophobic, porous surface with a metal which acts as a catalyst and conductive layer.

This standard architecture reduces if not eliminates the GDE’s through-plane conductivity which in turn limits the design space the GDE can be used in for the overall membrane electrode assembly (MEA), the core component of an electrochemical fuel cell. By using standard GDEs made with carbon felts and polytetrafluoroethylene (PTFE), front contact MEA architectures are required, which increase cell voltage thereby decreasing cell lifetime and charge uniformity.

There is a need for GDE designed with through plane conductivity that allow the cell to be constructed with a “back contact” to the GDE, which can significantly reduce cell voltage and improve charge uniformity.

Description: LLNL researchers have developed a novel method of making a GDE that starts with a porous, conductive structural framework made from metallic materials which standalone would be too hydrophilic and macroporous. The conductive structural framework is then infilled with a hydrophobic monomeric solution and subsequently photopolymerized to make a porous hydrophobic polymer resin network that surrounds the conductive structural framework.

The tunable nature of the porous hydrophobic resin allows for application-specific tailoring of the infill’s properties. Once surrounded with resin, the GDE becomes hydrophobic and microporous and ready to be used in electrochemical fuel cells. The conductive structure provides the much needed mechanical support for the porous resin and prevents the collapse of pores during operation.

Since the entire structure is conductive, the final product contains through-plane conductivity and can therefore utilize a "back contact" method of current conduction instead of using a copper front contact method. This significantly reduces the cell voltage and offers higher charge uniformity, thus increasing cell lifespan and easier scale-up ability.

Advantages/Benefits: Tunable porosity of hydrophobic resin allows for application-specific designs. Conductive structural framework prevents collapse of the GDE pores in an operating cell. Through-plane conductivity allows for "back contact" method of current conduction. Increased cell lifespan and scale-up potential of the technology. More plug and play ready design compared with current industry standards.

Potential Applications: PEM and AEM electrolyzers CO2 reduction electrochemical fuel cells hydrogen fuel cells Development Status: Current stage of technology development: TRL 3 LLNL has filed for patent protection on this invention. LLNL is seeking industry partners with a demonstrated ability to bring such inventions to the market. Moving critical technology beyond the Laboratory to the commercial world helps our licensees gain a competitive edge in the marketplace.

All licensing activities are conducted under policies relating to the strict nondisclosure of company proprietary information. Please visit the IPO website at https://ipo.llnl.gov/resources for more information on working with LLNL and the industrial partnering and technology transfer process.

Note: THIS IS NOT A PROCUREMENT. Companies interested in commercializing LLNL's conductive framework impregnated with hydrophobic porous foam for use in electrochemical systems should provide an electronic OR written statement of interest, which includes the following:

Company Name and address. The name, address, and telephone number of a point of contact. A description of corporate expertise and/or facilities relevant to commercializing this technology. Please provide a complete electronic OR written statement to ensure consideration of your interest in LLNL's conductive framework impregnated with hydrophobic porous foam for use in electrochemical systems. The subject heading in an email response should include the Notice ID and/or the title of LLNL’s Technology/Business Opportunity and directed to the Primary and Secondary Point of Contacts listed below. Written responses should be directed to:

Lawrence Livermore National Laboratory Innovation and Partnerships Office P.O.

Box 808, L-779 Livermore, CA 94551-0808 Attention: IL-13957