众所周知,铂团聚和颗粒生长与燃料电池高度相关,由于在整个堆栈中观察到圆形和线性Pt沉积,假设 MPL 和 CCL 之间的空隙(如 CCM 的屈曲和线性起皱)以及 MPL 裂纹和孔洞是退化的起点。在所供气体的高电流密度和/或高相对湿度下,阴极的这些空隙被怀疑充满了液态水。此外,由于阳极可能存在缺氢,电极电位Uc根据反向电流机...
对于目前的PEMFC来说,在超低Pt载量的情况下(<0.1 mgPt/cm2),局部氧气传质阻力会导致较大的中高电流密度下的功率损失。 下图所述,在r.f.很小(<50)时,非菲克传质阻力会激增,以前这部分传质阻力均归结到Rother里面,现在可以细分为:MPL中的阻力、CCL中的阻力以及Pt附近的阻力,RNF≈RNFMPL+RNFCCL+RO2Ptr.f.。
表中PEMFC各组成部分的缩写代表:PEM —— Proton Exchange Membrane,质子交换膜;CL —— Catalyst Layer,催化层,ACL和CCL分别为阳极和阴极的;MPL —— Microporous Layer,微孔层;GDL —— Gas Diffusion Layer,气体扩散层;CH —— Channel,流道;BP —— Bipolar Plate,双极板; 质子交换膜无法透过气体(g),所以...
The capillary pressures in the MPLs and CCL are approximated using a polynomial function of liquid saturation. There was a significant increase in the diffusion resistance of oxygen in the CCL, while that in the MPLs and CCL was moderate, which indicates that the CCL is susceptible to flooding...
traditional CCL coating generated by the decal approach. When compared to a decaled CCL, inkjet-printed CCLs were shown to have a more uniform distribution of carbon support and ionomer. Inkjet-printed CCLs showed improved utilization of the Pt catalyst compared to conventional decaled cathodes, ...
基于低温启动特性的PEMFC水热性能仿真与分析 2021年第5期【摘要】为在控制燃料电池生成水量时，最大限度提升其发热功率及冷启动成功率，建立了质子交换膜燃料电池3D 仿 真模型，并引入水伴热值概念，对不同输出电压、阴极计量比下的电池内部热源发热功率占比、阴极催化层发热功率密度分布情况进行了计算。结果表明：当...
Oxygen diffusion in the cathode catalyst layer (CCL) is crucial to the high performance of polymer electrolyte membrane fuel cells (PEMFCs), especially in high current density or concentration loss regions. Recently, PEMFC performance has been reported to be enhanced by increasing CCL pore size ...
Liquid water saturation in the diffusion media (GDL, MPL) and the cathode catalyst layer (CCL) are determined by the balance of capillary pressures of the pores of each layer. Increase of the diffusion resistance of oxygen in the CCL is significant, while that in the diffusion media is ...
CCL would exit it over the CCL/GDL interface as vapor.Results,given here for a simple variant of the model,confirm the key role of the CCL for water management in PEMFC.Since critical liquid water formation seems to occur first in the middle of the CCL,it acts as a watershed for the ...
The modeling results demonstrated that catalyst degradation is more severe downstream as well as under land of the cathode flow field, and the cathode catalyst layer (CCL) is the area most contaminated by the Co2+. The non-uniform catalyst degradation as well as Co2+ contamination increased the...