Fuel cell fabrication using photopolymer based processes

1. A method for fabricating a fuel cell component, comprising the steps of:

providing a mask having a plurality of radiation transparent apertures, the plurality of radiation transparent apertures permitting a plurality of radiation beams to be directed therethrough;

providing a radiation-sensitive material having a sensitivity to the plurality of radiation beams;

providing a flow field layer;

disposing the radiation-sensitive material on the flow field layer;

exposing the radiation-sensitive material to the plurality of radiation beams through the radiation transparent apertures in the mask to form a diffusion medium layer with a micro-truss structure;

applying a sacrificial release layer to the mask, the sacrificial release layer being substantially transparent to the plurality of radiation beams; and

applying the radiation-sensitive material to the sacrificial release layer.

2. The method of claim 1 , wherein the sacrificial release layer is spin coated onto the mask.

3. The method of claim 1 , wherein the sacrificial release layer is formed from polystyrene.

4. The method of claim 1 further comprising the step of:

removing the mask and the sacrificial release layer from the diffusion medium layer after the radiation-sensitive material is exposed to the plurality of radiation beams.

5. The method of claim 4 , wherein the sacrificial release layer is removed by immersing the release layer and the mask in a solvent that dissolves the release layer and permits removal of the mask.

6. The method of claim 5 , wherein an uncured portion of the radiation-sensitive material remaining after the radiation-sensitive material is exposed to the plurality of radiation beams is cleaned from the diffusion medium layer prior to dissolving the release layer in the solvent.

7. The method of claim 1 , wherein the flow field layer is embedded in the radiation-sensitive material when the radiation-sensitive material is disposed on the flow field layer, and wherein the micro-truss structure of the diffusion medium layer is interlocked with the flow field layer after the diffusion medium layer is formed.

8. The method of claim 1 , wherein the mask is a radiation transparent material coated with a radiation opaque material, the radiation opaque material having a plurality of holes defining the radiation transparent apertures of the mask.

9. The method of claim 8 , wherein the radiation transparent apertures of the mask are substantially circular.

10. The method of claim 8 , wherein the radiation transparent material is glass and the radiation opaque material is a patterned chromium coating.

11. The method of claim 1 , wherein the radiation-sensitive material is heated to minimize residual stress prior to being disposed on the flow field layer.

12. The method of claim 1 , wherein the diffusion medium layer is bonded to the flow field layer during the formation of the diffusion medium layer.

13. The method of claim 1 , wherein the mask is positioned a distance from the radiation-sensitive material when the radiation-sensitive material is exposed to the plurality of radiation beams.

14. The method of claim 1 , wherein the flow field layer is formed on a substrate.

15. The method of claim 14 , wherein the substrate is a metal foil and the flow field layer includes a plurality of radiation-cured reactant flow channels.

16. The method of claim 15 , wherein the plurality of radiation-cured reactant flow channels include an adhesion promoter that enhances a bonding of the radiation-cured reactant flow channels to the metal foil.

17. The method of claim 1 , further comprising the steps of coating at least one of the diffusion medium layer and the flow field layer with an electrically conductive coating.

18. A method for fabricating a fuel cell component, comprising the steps of:

providing a mask having a plurality of radiation transparent apertures, the plurality of radiation transparent apertures permitting a plurality of radiation beams to be directed therethrough;

applying a sacrificial release layer to the mask, the release layer being substantially transparent to the plurality of radiation beams;

applying a radiation-sensitive material to the release layer, the radiation-sensitive material having a sensitivity to the plurality of radiation beams;

providing a substrate having a flow field layer disposed thereon, the flow field layer having a plurality of radiation-cured reactant flow channels;

disposing the radiation-sensitive material on the flow field layer of the fuel cell component;

exposing the radiation-sensitive material to the plurality of radiation beams through the radiation transparent apertures in the mask to form a diffusion medium layer with a micro-truss structure; and

removing the mask and the release layer from the diffusion medium layer.

19. A method for fabricating a fuel cell component, comprising the steps of:

providing a mask having a plurality of radiation transparent apertures, the plurality of radiation transparent apertures permitting a plurality of radiation beams to be directed therethrough;

providing a radiation-sensitive material having a sensitivity to the plurality of radiation beams;

providing a diffusion medium layer with a micro-truss structure;

disposing the radiation-sensitive material on the diffusion medium layer;

exposing the radiation-sensitive material to the plurality of radiation beams through the radiation transparent apertures in the mask to form a flow field layer;

forming a first channel wall in the flow field layer, the first channel wall defined by a self-propagating polymer wall waveguide; and

forming a plurality of spaced apart support ligaments between the first channel wall and one of the diffusion medium layer and a substrate, the ligaments defined by a plurality of self-propagating polymer ligament waveguides.