Apparatus for measuring micro-cracks in a membrane electrode assembly and method for predicting generation of micro-cracks in the same

Patent metadata

Field	Value
Publication number	US-10109044-B2
Application number	US-201514942390-A
Country	US
Kind code	B2
Filing date	Nov 16, 2015
Priority date	Jul 1, 2015
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

An apparatus for measuring micro-cracks in a membrane electrode assembly includes a resistance measurement unit to measure variation in electrical resistance of the membrane electrode assembly while tensioning the membrane electrode assembly in a state in which power is applied to an upper catalyst layer while a lower catalyst layer is insulated, an image capture unit to capture an image of micro-cracks in the upper catalyst layer while the membrane electrode assembly is being tensioned, and a controller to detect, in real time, variation in electrical resistance measured by the resistance measurement unit, corresponding to the image of micro-cracks captured by the image capture unit, and to interpret the size of the micro-cracks generated in the membrane electrode assembly based on the detected variation in electrical resistance.

First claim

What is claimed is:

1. An apparatus for measuring micro-cracks in a membrane electrode assembly for a fuel cell, the membrane electrode assembly being formed with an upper catalytic layer and a lower catalytic layer on an upper surface and a lower surface of a polymer electrolyte membrane, respectively, the apparatus comprising:
a resistance measurement unit configured to clamp the upper catalyst layer and the lower catalyst layer of the membrane electrode assembly, the resistance measurement unit serving to measure variation in electrical resistance of the membrane electrode assembly while tensioning both sides of the membrane electrode assembly in a state in which power is applied to both end parts of only the upper catalyst layer of the membrane electrode assembly while the lower catalyst layer of the membrane electrode assembly is insulated;
an image capture unit disposed directly above the membrane electrode assembly and serving to capture an image of micro-cracks generated in the upper catalyst layer of the membrane electrode assembly while the membrane electrode assembly is being tensioned by the resistance measurement unit; and
a controller configured to detect, in real time, the variation in electrical resistance, measured by the resistance measurement unit, corresponding to the image of micro-cracks captured by the image capture unit, and to interpret the size of the micro-cracks generated in the membrane electrode assembly based on the detected variation in electrical resistance.

2. The apparatus according to claim 1 , wherein the resistance measurement unit includes:
a pair of dampers configured to clamp both sides of the membrane electrode assembly in the state in which power is applied to only the upper catalyst layer of the membrane electrode assembly while the lower catalyst layer of the membrane electrode assembly is insulated;
tensioners connected to the respective dampers to provide tensile force required to increase a distance between the dampers; and
a measurer electrically connected to the upper catalyst layer of the membrane electrode assembly and serving to measure variation in electrical resistance at the upper catalyst layer of the membrane electrode assembly as the tensioners are operated.

3. The apparatus according to claim 2 , wherein each of the dampers includes:
a damper main body formed of an insulation material, the damper main body having a seating recess formed to a prescribed depth in an upper surface thereof, and a specimen recess formed to a greater depth than the thickness of the seating recess in a middle region of the seating recess for seating of the membrane electrode assembly;
a conductive cover formed of a conductive material, the conductive cover being seated in the seating recess of the damper main body so as to be connected to the upper catalyst layer of the membrane electrode assembly;
a bonding member formed of an insulation material, the bonding member being disposed between the specimen recess and the lower catalyst layer of the membrane electrode assembly; and
a coupling member configured to couple the conductive cover to the damper main body.

4. The apparatus according to claim 2 , wherein each of the tensioners includes:
a rod fixed to a corresponding one of the dampers; and
a cylinder body configured to operate the rod so as to increase the distance between the dampers.

5. The apparatus according to claim 1 , wherein the image capture unit is an optical microscope.

6. A method for predicting the extent of generation of micro-cracks in a membrane electrode assembly for a fuel cell, the membrane electrode assembly being formed with an upper catalytic layer and a lower catalytic layer on an upper surface and a lower surface of a polymer electrolyte membrane, respectively, the method comprising the steps of:
fabricating a specimen of the membrane electrode assembly;
measuring variation in electrical resistance at both end parts of only a selected one of the upper catalyst layer and the lower catalyst layer of the fabricated specimen while tensioning the specimen, while an unselected one of the upper catalyst layer and the lower catalyst layer is insulated;
capturing, in real time, an image of micro-cracks generated in the catalyst layer, the variation in electrical resistance of which being measured;
generating data pertaining to the size of micro-cracks based on variation in electrical resistance by detecting, in real time, the measured variation in electrical resistance corresponding to the captured image of micro-cracks, and interpreting the size of micro-cracks generated in the specimen based on the detected variation in electrical resistance; and
predicting the extent of generation of micro-cracks in a new membrane electrode assembly by measuring variation in electrical resistance at a selected one of an upper catalyst layer and a lower catalyst layer of the new membrane electrode assembly while the membrane electrode assembly is tensioned, and comparing the measured variation in electrical resistance with the generated data.

7. The method according to claim 6 , wherein the data pertaining to the size of micro-cracks based on the variation in electrical resistance is generated by repeatedly implementing the steps of fabricating, measuring, and capturing.

Assignees

• Hyundai Motor Co Ltd
• Korea Advanced Inst Sci & Tech

Inventors

• Jeong Byeong-Heon
• Hong Bo Ki
• Oh Jong Kil
• Kim Taek-Soo
• Kim Sanwi
• Jang Kyung-Rim

Classifications

• G01N2203/0066

  Propagation of crack · CPC title

• G06T7/0004 Primary

  Industrial image inspection · CPC title

• G06T2207/30108

  Industrial image inspection · CPC title

• G01N27/205

  in insulating materials · CPC title

• G06T2207/10056

  Microscopic image · CPC title