Texture and morphology based conductivity analysis of fuel cell - bipolar plate using scanning electron microscopic images

Abstract

The main objective of this work is to analyze strength and conductivity of the fuel cell bipolar plate using microstructural analysis. This paper focuses on the structural characterization of fuel cell by texture and morphological analysis of its composite bipolar plate which is the major component of the proton exchange membrane (PEM) fuel cell stack. The composite plates were prepared with compression molding technique using activated charcoals and epoxy (araldite) at various temperatures ranging between 170°C and 190°C with the pressure of 20 bar. Texture and morphological structures of a composite are directly related with the strength and conductivity of the material. The internal structures of the composite bipolar plate are acquired using scanning electron microscope (SEM) which provides microstructural information of the specimen. In this paper, nature of bonding in SEM image is detected using texture and morphological features. Texture features derived from Gray level co-occurrence matrix (GLCM) and Tamura is used to characterize the arrangement of molecules and nature of bonding. Gray level co-occurrence matrix (GLCM) and Tamura based approach is used to calculate texture features. These textural features analyze the internal textures of each samples prepared. Morphological operations are used to find the area covered by each discontinuous region where the discontinuity affects the bonding and thus the strength and conduction. The image processing approach analyses the internal structure of the prepared samples and validates its flexural strength and electrical conductivity performed experimentally. The sample prepared at 190^oC and pressure 20 bar has met the target value defined by the US, Department of Energy (DOE) and has homogeneous internal structure with less discontinuities and better bonding among the prepared samples.