Leland Stanford Junior University

Honda Motor Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Suk-Won Cha

Yuji Saito

Friedrich B Prinz

Jun Sasahara

Tadahiro Kubota

Tibor Fabian

Sang-Joon John Lee

Toshifumi Suzuki

Nariaki Kuriyama

Daniel Braithwaite

Ryan Patrick O'Hayre

Yong-Il Park

Sangkyun Kang

Ali Farvid

Pei-Chen Su

Juan G Santiago

John K Eaton

Hideaki Tsuru

Jonathan Posner

Cullen Buie

Daejoogn Kim

Water flooding at the cathode of a fuel cell is a common problem in fuel cells. By integrating an electroosmotic (EO) pump to remove product water from the cathode area, fuel cell power can be increased. Integration of EO pumps transforms the designs of air channel and air breathing cathodes, reducing air pumping power loads and increasing oxidant transport. Hydration of gas streams, management of liquid reactants, and oxidant delivery can also be accomplished with integrated electroosmotic pumps. Electroosmotic pumps have no moving parts, can be integrated as a layer of the fuel cell, and scale with centimeter to micron scale fuel cells.

Fuel cell with electroosmotic pump

A simple, inexpensive and highly efficient fuel cell has boundary structures made of a photo-sensitive material in combination with selective patterning. Printed circuit board (PCB) fabrication techniques combine boundary structures with two and three dimensional electrical flow path. Photo-sensitive material and PCB fabrication techniques are alternately or combined utilized for making micro-channel structures or micro stitch structures for substantially reducing dead zones of the diffusion layer while keeping fluid flow resistance to a minimum. The fuel cell assembly is free of mechanical clamping elements. Adhesives that may be conductively contaminated and/or fiber-reinforced provide mechanical and eventual electrical connections, and sealing within the assembly. Mechanically supporting backing layers are pre-fabricated with a natural bend defined in combination with the backing layers' elasticity to eliminate massive support plates and assist the adhesive bonding. Proton insulation between adjacent and electrically linked in-plane cell elements is provided by structural insulation within the central membrane.

Fuel cell

An improved two-step replication process for fabrication of porous metallic membranes is provided. A negative of a porous non-metallic template is made by infiltration of a liquid precursor into the template, curing the precursor to form a solid negative, and removing the template to expose the negative. Metal is deposited to surround the exposed negative. Removal of the negative provides a porous metallic membrane having pores which replicate the pores of the original template membrane. The negative is kept immersed in a liquid at all times between removing the template and depositing the metal. This immersion eliminates damage to the negative that would be incurred in drying the negative out between these processing steps. Another aspect of the invention is metallic membranes prepared according to the preceding method. For example, metallic membranes having pores smaller on one side than on the other side of the membrane are provided.

Gas/ion species selective membrane support by multi-stage nano-hole array metal structure

A fluid impermeable thin film is fabricated on a porous substrate by depositing a material having a certain spatial oxidation expansion. After deposition, the material is oxidized whereby the deposited material expands and forms a void free film on top of the porous substrate. The snuggly contacting grain boundaries of the void free film may recombine to a continuous thin film that has a thickness of only a fraction of 1 &#x3bc;m and is substantially fluid impermeable. The small film height contributes to a high ionic conductivity that makes the thin film a preferred choice for a fuel cell electrolyte membrane enabling efficient fuel cell operation at temperatures well below 500&#xb0; C.

Sub-micron electrolyte thin film on nano-porous substrate by oxidation of metal film

Gas/ion species selective membrane supported by multi-stage nano-hole array metal structure

Growing community of inventors

Stanford, CA, United States of America

Suk-Won Cha