Study on the performance of a proton exchange membrane fuel cell related to the structure design of a gas diffusion layer substrate

Solutions to the water flooding problem for unitized regenerative fuel cells: status and perspectives

“…The parts of the GDL consists of small hydrophobic pores (which should be ideally as small as possible) that are not lled with water and provide a pathway for the reactant gases. 93,94 A moderate pore size gradient was found to benecial for the removal of excess product from the catalyst layer. Sadeghifar et al 95 proposed an analytical model for the prediction of the thermal contact resistance between brous porous media and at surfaces that is applicable to FC mode.…”

Effects of pore size gradient in the substrate of a gas diffusion layer on the performance of a proton exchange membrane fuel cell

“…In general, the transient response of the voltage has two types of time delays related to the gas balance and the liquid water balance inside the GDL [22,[26][27][28][29]. As the load rapidly increases, the membrane instantly becomes dehydrated by the increased electro-osmotic drag and generated heat.…”

“…11. Schematic of (a) water balance on the membrane influenced by the flux of water through GDLs and (b) capillary pressure gradient through a GDL [22,26,29]. …”

“…While the MPL drains water from the cathode's catalyst layer, the substrate manages the drained water and possesses more water within its thicker and more porous structure [23][24][25]. Therefore, in one of our studies, we designed the substrate by using activated carbon fibers (ACFs), which have a surface area larger than that of normal GDLs [26]. We produced pores of uniform size by distributing carbon filler and carbonized resin evenly on the surface of the ACFs.…”

A review of the gas diffusion layer in proton exchange membrane fuel cells: Durability and degradation

“…The membranes need to be hydrated to maintain high proton conductivity and ensure adequate fuel cell performance. However, excess water in the electrodes can result in electrode flooding, which prevents electrochemical reactions from occurring and reduces performance, thus a careful balance must be maintained [6][7][8][9][10][11][12][13][14][15][16][17]. In this respect, the gas diffusion layer (GDL) which is in contact with catalyst layer is one of the critical components of a fuel cell that has the ability to influence the system performance because its basic functions are transporting the reactant gas from the flow channel to the catalyst layer, draining liquid water from the catalyst layer to the flow channel, conducting electrons with low resistance, and keeping the membrane in a wet condition at low humidity.…”