Fabrication and electrochemical performance of Poly (2,5-benzimidazole) (ABPBI)-based MEA by catalyst coated membrane (CCM) method for high-temperature polymer electrolyte fuel cells

The interfacial impedance between membrane and catalyst layer in membrane electrode assembly (MEA) is of great critical for the electrochemical performances of a proton exchange membrane fuel cell. To minimize the interfacial impedance, a series of Poly (2, 5-benzimidazole) (ABPBI)-based MEA were fabricated by catalyst coated membrane (CCM) method. Two kinds of proton exchange resin solution were used in the CCM process and the H3PO4 loading in the CCM catalyst layer was varied. The electrochemical performances such as polarization curve, AC impedance, cyclic voltammetry and stability of the obtained MEAs were studied and compared with the MEA fabricated by gas diffusion electrode (GDE) method. The results indicated that the impedance can be decreased through CCM method compared with GDE method and the MEA fabricated by CCM method with ABPBI as proton exchange agent and 10 mg/cm2 H3PO4 dosages exhibited the optimal electrochemical performances.