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Summary: The performance and durability of the proton exchange membrane fuel cells (PEMFCs) are highly influenced by the transport of reactants and water distribution in the cathode flow field. In this study, a novel staggered structure is proposed for the cathode flow field, and the effects of flow field geometric parameters on the transport and distribution characteristics of water and oxygen in the fuel cell are studied by numerical simulation. Two parameters are considered, namely the size of the hole (W) and the number of segments in which the channel is divided equally (L). The simulation results show that compared with the traditional parallel flow field, when W = 0.5 mm, the current density of PEMFC has increased by 11.9%, and the uniformity of oxygen and water concentration distribution inside the fuel cell has been significantly improved. In addition, when W = 0.5 mm and L = 5.56 mm, the fuel cell shows the best performance with 15.8% increase in power density. In this case, the fuel cell shows a more uniform current density distribution. Meanwhile, the staggered flow field reduces the maximum water saturation by 42.5% and without increasing the total pressure drop vs the conventional parallel flow field. Highlights: The staggered flow field (SFF) is proposed to improve species concentration distribution.The power density of PEMFC with SFF has increased by 15.8%.The drainage performance of SFF is significantly improved, maximum water saturation of PEMFC is reduced by 42.5%.This new structure does not increase the pressure drop of the cathode channel. [ABSTRACT FROM AUTHOR]

Water flooding in the cathode channel of the proton exchange membrane fuel cell (PEMFC), which reduce the current density output and affect fuel cell lifetime. Hence, to suppress water flooding, a novel channel is proposed in this study, that is to perforate hole between the cooling channel and cathode channel. A 3D numerical model is used to investigate the influence of the parameters including the hole's dimension, position, numbers, the operation conditions of the PEMFC and the slope angle ( θ ) of the incline cooling channel. The numerical results indicate that the optimal single hole parameters are 0.4 mm long, 0.5 mm wide and 20 mm position, which can maximum the current density output of the PEMFC. Increasing the hole numbers for novel channels can improve water removal. In addition, in comparison with the conventional channel with θ = 0.20° at 1.8 cathode stoichiometry, the H5 (novel channel with five holes) with θ = 0.20° decreases by 43.10% in the maximum water saturation of cathode channel, while increases by 12.54% in current density output. What's more, all the novel channel structure research hardly raises the pressure drop of channels. • A novel channel with a low pressure drop is proposed. • The effect of channel structure parameters is investigated in detail. • Inclined cooling channel design can improve water management capabilities. • The maximum water saturation in the novel channel can be reduced by 43.10%. [ABSTRACT FROM AUTHOR]