Abstract Air-cooled open-cathode LTPEMFC (AO-LTPEMFC) has been developed as a new power source for the portable power supply. The effect of the gas diffusion layer (GDL) on AO-LTPEMFC operation in challenging ambient air conditions was investigated in the present study. The effect of the content of polytetrafluoroethylene (PTFE) on the substrate layer and microporous layer (MPL), the thickness of GDL and the pulse width modulation (PWM) of the fan on cell performance as well as the cathode outlet surface temperature distribution were investigated. The polarization curves, electrochemical impedance spectroscopy (EIS) and dynamic voltage test were used to correlate the structural characteristics of GDL with heat dissipation, oxygen transport and water management in AO-LTPEMFC. The results showed that GDL with appropriate PTFE content in the substrate layer and MPL could significantly optimize cell performance. In addition, the thickness of GDL also had a certain impact on the mass and heat transfer of the fuel cell, while the water management in GDL was affected by PWM of the fan, simultaneously. Combined with the practice process, the optimum values of the substrate layer PTFE content, MPL layer PTFE content and thickness of GDL were identified to be 10%, 40%, and 200 μm, respectively.

中文翻译：

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不同气体扩散层设计参数的风冷开式阴极质子交换膜燃料电池性能提升

摘要 风冷开式阴极LTPEMFC（AO-LTPEMFC）是一种新型的便携式电源。本研究调查了气体扩散层 (GDL) 在具有挑战性的环境空气条件下对 AO-LTPEMFC 运行的影响。研究了聚四氟乙烯（PTFE）对基板层和微孔层（MPL）的含量、GDL的厚度和风扇的脉宽调制（PWM）对电池性能以及阴极出口表面温度分布的影响. 极化曲线、电化学阻抗谱 (EIS) 和动态电压测试用于将 GDL 的结构特征与 AO-LTPEMFC 中的散热、氧气传输和水管理相关联。结果表明，在基底层和 MPL 中具有适当 PTFE 含量的 GDL 可以显着优化电池性能。此外，GDL的厚度对燃料电池的传质和传热也有一定的影响，同时GDL中的水分管理受到风扇PWM的影响。结合实际工艺，确定基材层PTFE含量、MPL层PTFE含量和GDL厚度的最佳值分别为10%、40%和200 μm。