Date of Award


Document Type



Santa Clara : Santa Clara University, 2016.

Degree Name

Master of Science (MS)


Mechanical Engineering

First Advisor

Hohyun Lee

Second Advisor

Drazen Fabris


Passive Unitized Regenerative Fuel Cell (PUReFC) prototypes were designed, fabricated, and tested as new energy storage devices capable of meeting demands in offgrid applications. Although flooded lead-acid batteries are typically used to provide low cost energy storage, improper disposal infrastructure and lack of education on battery maintenance can lead to serious health concerns. A Passive Unitized Regenerative Fuel Cell can generate energy in a sustainable manner and possesses the ability to run in reverse, providing energy storage capability.

As Proton Exchange Membrane (PEM) fuel cells rely on effective internal water transport to provide stable operation, an energy efficient flood mitigation strategy is crucial to enhance performance of PUReFCs. The Passive Unitized Regenerative Fuel Cell eliminates the introduction of parasitic losses from active management methods by leveraging the capillarity of porous polymer wicking structures to passively remove excess water. The water management concept features two connected porous domains consisting of a methacrylate-based polymer and a polyvinyl alcohol storage element, each with different pore sizes to induce capillary flow. In the first prototype, large water transport lengths (~12 mm) prevented adequate removal of generated water during sustained operation; the capillary pressure drop across the two porous domains was insufficient to match the water production rate. The improved design produces a shorter transport length (~3 mm) by implementing a new vertical layout.