Structure Design for Ultrahigh Power Density Proton Exchange Membrane Fuel Cell

Area of Science:

• Electrochemistry
• Materials Science
• Energy Conversion

Background:

• Proton exchange membrane fuel cells (PEMFCs) are key for clean energy.
• Achieving ultrahigh power density requires both high-performance membrane electrode assemblies (MEAs) and optimal cell structures.

Purpose of the Study:

• To comprehensively investigate how various cell structures impact PEMFC performance.
• To identify unexploited performance improvements through structural design modifications.

Main Methods:

• Investigated various cell structures and their effects on gas supply and proton/electron conduction.
• Explored the use of fine channel/rib or porous flow fields to eliminate the gas diffusion layer (GDL).
• Analyzed the impact of structural changes on cell thickness and transfer resistances.

Main Results:

• Optimizing cell structure can enhance gas supply but may hinder proton/electron conduction.
• Eliminating the GDL using fine channel/rib or porous flow fields significantly increases power density.
• A combined structure (fine channel/rib, GDL elimination, double-cell) improved power density from 4.4 to 6.52 kW L⁻¹ with an existing MEA.

Conclusions:

• Cell structure design is as critical as MEA development for achieving high power density targets (e.g., 9.0 kW L⁻¹).
• Structural modifications, particularly GDL elimination, offer substantial power density gains in PEMFCs.