Reversible (unitized) PEM fuel cell devices

Conference · Tue Jun 01 04:00:00 EDT 1999

OSTI ID:9867

Mitlitsky, F ^[1]; Myers, B; Smith, W F

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1. LLNL

Regenerative fuel cells (RFCs) are enabling for many weight-critical portable applications, since the packaged specific energy (>400 Wh/kg) of properly designed lightweight RFC systems is several-fold higher than that of the lightest weight rechargeable batteries. RFC systems can be rapidly refueled (like primary fuel cells), or can be electrically recharged (like secondary batteries) if a refueling infrastructure is not conveniently available. Higher energy capacity systems with higher performance, reduced weight, and freedom from fueling infrastructure are the features that RFCs promise for portable applications. Reversible proton exchange membrane (PEM) fuel cells, also known as unitized regenerative fuel cells (URFCs), or reversible regenerative fuel cells, are RFC systems which use reversible PEM cells, where each cell is capable of operating both as a fuel cell and as an electrolyzer. URFCs further economize portable device weight, volume, and complexity by combining the functions of fuel cells and electrolyzers in the same hardware, generally without any system performance or efficiency reduction. URFCs are being made in many forms, some of which are already small enough to be portable. Lawrence Livermore National Laboratory (LLNL) has worked with industrial partners to design, develop, and demonstrate high performance and high cycle life URFC systems. LLNL is also working with industrial partners to develop breakthroughs in lightweight pressure vessels that are necessary for URFC systems to achieve the specific energy advantages over rechargeable batteries. Proton Energy Systems, Inc. (Proton) is concurrently developing and commercializing URFC systems (UNIGEN' product line), in addition to PEM electrolyzer systems (HOGEN' product line), and primary PEM fuel cell systems. LLNL is constructing demonstration URFC units in order to persuade potential sponsors, often in their own conference rooms, that advanced applications based on URFC s are feasible. Safety and logistics force these URFC demonstration units to be small, transportable, and easily set up, hence they already prove the viability of URFC systems for portable applications.

• Research Organization: Lawrence Livermore National Lab., CA (US)
• Sponsoring Organization: USDOE Office of Defense Programs (DP) (US)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 9867
• Report Number(s): UCRL-JC-134538; YN0100000; YN0100000
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
DESIGN
EFFICIENCY
ELECTROLYSIS
HYDROGEN PRODUCTION
PERFORMANCE
PROTON EXCHANGE MEMBRANE FUEL CELLS
REGENERATIVE FUEL CELLS
SAFETY