Porous Composite Gas Diffuser for Lower Fuel Cell Head Loss

The patent applies composite materials by combining metal sheets with corrosion-resistant coatings or alternative materials that provide both mechanical strength and corrosion resistance. The bipolar plates are designed as composite structures where the metal substrate provides structural integrity while surface treatments or coating layers protect against corrosion and prevent cation formation.

The patent employs parameter changes by modifying the stamping process parameters (such as punch geometry, pressure, temperature) to achieve a broader range of channel dimensions and configurations. This allows the manufacturing process to produce varied flow channel designs while maintaining high production efficiency.

The patent utilizes porous materials with optimized pore size distribution, porosity, and thickness to reduce head losses while minimizing stack bulk. The gas diffusion layers are designed with specific porous structures that facilitate reagent transport with lower resistance, allowing thinner layers to achieve the same performance that would otherwise require thicker configurations.

The patent applies local quality by creating regions with different properties within the gas diffusion layers. Specific zones are optimized for gas diffusion with higher porosity and thinner sections to improve reagent distribution, while adjacent regions maintain lower porosity and thicker sections to ensure good electrical contact with the bipolar plates, thus balancing both requirements locally.