In this work, a high temperature proton exchange membrane fuel cell (HT-PEMFC) with stamped SS304 bipolar plates is successfully developed. Its performance was evaluated under two types of gaskets at different assembly torques and air stoichiometric ratios. The rates of pressure loss at a torque of 7 N-m with 50 Shore A hardness gaskets was 2.0 x 10(-3) MPa min(-1), which is acceptable. The best performance of the developed HT-PEMFC with stamped SS304 bipolar plates was 228.33 mW cm(-2), which approaches the performance of HT-PEMFCs with graphite bipolar plates. The optimal air stoichiometric ratio for the HT-PEMFC with stamped SS304 bipolar plates was 4.0, which is higher than that for proton exchange membrane fuel cells with CNC milled graphite bipolar plates. This is probably because of the deformation of the flow channels under the assembly compression force, which causes an elevated gas-diffusion drag in the flow channels. After the test, it was observed that some products of corrosion reaction formed on the surface of the SS304 bipolar plate. This phenomenon may lead to a decrease in the operating life of the HT-PEMFC. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

In this work, a proton exchange membrane fuel cell with stamped 304 stainless steel bipolar plates is successfully assembled, The total weight of the bipolar plates, membrane electrode assembly and gaskets in the fuel cell is reduced by 37% when replacing milled graphite plates by the stamped 304 stainless steel plates. Moreover, the gas leaking rates and electrochemical characteristics of the fuel cell at different assembly torques are studied. It is found that increasing the torque increases the sealing performance. However, an excess torque (>6 N-m) decreases the power due to a decrease in the porosity and hydrophobicity of the gas diffusion layer, and a deformation of the flow channels in the metallic plate. The pressure loss rate declines by 56% as the torque increases from 2 N-m to 7 N-m. The best performance is obtained at 6 N-m. The cell performance increases by about 21% as the torque increases from 2 N-m to 6 N-m. However, the performance decreases by about 11% as the torque further increases from 6 N-m to 7 N-m. The suspected reason for the above phenomenon is verified via the electrochemical impedance spectroscopies and the microscopic images of the gas diffusion layer. (C) 2018 Elsevier Ltd. All rights reserved.