Experimental and mechanistic studies of gradient pore polymer electrolyte fuel cells

Abstract This article uses carbon black as a conductive material, polytetrafluoroethylene as a hydrophobic material, and calcium carbonate (CaCO 3 ) as a pore-forming agent. Meanwhile, a gas diffusion layer (GDL) with a gradient pore size was prepared using the spray coating method. The results show that a three-layer gradient pore size GDL has good water vapor transmission ability. When humidity is 40%, the current density and power density of gradient pore size GDL are 127.9 mA·cm −2 and 63.31 mW·cm −2 higher than commercial GDL29BC, respectively. When humidity is 60%, the current density and power density of gradient pore size GDL are 250.3 mA·cm −2 and 127.3 mW·cm −2 higher than commercial GDL29BC, respectively. When humidity is 100%, the current density and power density of the gradient pore size GDL are 255.69 mA·cm −2 and 127 mW·cm −2 higher than commercial GDL29BC, respectively.