Fuel Cell and Method of Forming the Same

Abstract

In an embodiment, a fuel cell includes: a flexible substrate including a first fuel-tolerant material; a fitting on the flexible substrate, the fitting including first openings extending through an outer portion of the fitting; a primer coating on the outer portion of the fitting, the primer coating including a second fuel-tolerant material; first yarns strung through the first openings of the fitting, the first yarns stitched into the flexible substrate; and an encapsulant encapsulating the first yarns, the primer coating, and the outer portion of the fitting, the encapsulant disposed on the flexible substrate, the encapsulant including a third fuel-tolerant material, the third fuel-tolerant material chemically bonded to the second fuel-tolerant material and the first fuel-tolerant material.

What is claimed is: 
     
         1 . A method comprising:
 receiving a fitting comprising openings extending through an outer portion of the fitting;   placing the fitting on a flexible substrate;   stitching main yarns into the flexible substrate, the main yarns strung through the openings of the fitting; and   encapsulating the main yarns and the outer portion of the fitting with an encapsulant, the encapsulant bonded to the flexible substrate.   
     
     
         2 . The method of  claim 1 , further comprising:
 forming a primer coating on the outer portion of the fitting, the encapsulant bonded to the primer coating.   
     
     
         3 . The method of  claim 1 , wherein the flexible substrate is formed of a first fuel-tolerant material and the encapsulant is formed of a second fuel-tolerant material. 
     
     
         4 . The method of  claim 1 , further comprising:
 stitching support yarns into the flexible substrate and over the main yarns, the support yarns crossing the main yarns.   
     
     
         5 . The method of  claim 4 , further comprising:
 encapsulating the support yarns with the encapsulant.   
     
     
         6 . The method of  claim 1 , wherein the main yarns are bicomponent yarns comprising a core and a sheath. 
     
     
         7 . The method of  claim 6 , wherein the sheath has a melting point, and the encapsulant is formed at a temperature which is lower than the melting point of the sheath. 
     
     
         8 . The method of  claim 1 , wherein stitching the main yarns into the flexible substrate comprises:
 threading bundles of the main yarns through respective ones of the openings of the fitting, the main yarns of the bundles radiating from the openings.   
     
     
         9 . The method of  claim 8 , wherein the main yarns of the bundles curve in a same direction as the main yarns radiate from the openings. 
     
     
         10 . A method comprising:
 receiving a fitting comprising openings extending through an outer portion of the fitting;   placing the fitting on a fuel-tolerant substrate;   forming an attachment structure by:
 programming a computer numerical control process according to a strength of the attachment structure; 
 stitching yarns into the fuel-tolerant substrate with an embroidering machine, the embroidering machine controlled using the computer numerical control process, the yarns strung through the openings of the fitting; and 
 encapsulating the yarns and the outer portion of the fitting with an encapsulant. 
   
     
     
         11 . The method of  claim 10 , wherein the fuel-tolerant substrate is a flexible substrate for a fuel cell fitting patch. 
     
     
         12 . The method of  claim 10 , wherein the fuel-tolerant substrate is a flexible body of a fuel cell. 
     
     
         13 . The method of  claim 10 , wherein programming the computer numerical control process comprises:
 selecting a density, a length, and a radius of curvature for the yarns.   
     
     
         14 . The method of  claim 10 , wherein the yarns each comprise a sheath having a melting point, and a molding process for the encapsulant is performed at a temperature which is lower than the melting point of the sheath. 
     
     
         15 . A method comprising:
 placing a first rigid fitting and a second rigid fitting on a first flexible substrate and a second flexible substrate, respectively, the first rigid fitting comprising first openings extending through a first outer portion of the first fitting, the second rigid fitting comprising second openings extending through a second outer portion of the second fitting;   stitching first yarns through the first openings and into the first flexible substrate with an embroidering machine, the embroidering machine controlled according to a first computer numerical control process;   stitching second yarns through the second openings and into the second flexible substrate with the embroidering machine, the embroidering machine controlled according to a second computer numerical control process, the second computer numerical control process different from the first computer numerical control process; and   encapsulating the first yarns, the second yarns, the first rigid fitting, and the second rigid fitting with an encapsulant, the encapsulant extending through the first openings and the second openings.   
     
     
         16 . The method of  claim 15 , wherein the first yarns form a first semi-rigid attachment structure for the first rigid fitting, and the second yarns form a second semi-rigid attachment structure for the second rigid fitting, the method further comprising:
 selecting the first computer numerical control process according to a first strength of the first semi-rigid attachment structure; and   selecting the second computer numerical control process according to a second strength of the second semi-rigid attachment structure, the second strength different from the first strength.   
     
     
         17 . The method of  claim 15 , wherein the first rigid fitting and the first flexible substrate form a first fitting patch, the second rigid fitting and the second flexible substrate form a second fitting patch, and the method further comprises:
 attaching the first fitting patch to a first side of a flexible fuel cell body; and   attaching the second fitting patch to a second side of the flexible fuel cell body.   
     
     
         18 . The method of  claim 15 , wherein the first rigid fitting is smaller than the second rigid fitting. 
     
     
         19 . The method of  claim 15  further comprising:
 forming a first primer coating on the first outer portion of the first fitting; and 
 forming a second primer coating on the second outer portion of the second fitting. 
 
     
     
         20 . The method of  claim 19 , wherein the first yarns and the second yarns comprise a filament component having a melting point, the encapsulant comprises a polyurethane resin formulated from isocyanate and polyol, and the polyurethane resin is formulated at a temperature lower than the melting point of the filament component.