这篇文章中的双极板材料不包含流道。

Measurement and Prediction of ElectricalContact Resistance Between Gas Diffusion Layers and Bipolar Plate forApplications to PEM Fuel Cells

V． Mishra

F． Yang

R． Pitchumani

The electrical contact resistance betweengas diffusion layers and bipolar flow channel plates is one of the importantfactors contributing to the operational voltage loss in polymer electrolytemembrane （PEM） fuel cells． Effective analysis and design of fuel cellstherefore need to account for the contact resistance in deriving thepolarization curve for the cell． Despite its significance， relatively scantwork is reported in the open literature on the measurement and modeling of thecontact resistance in fuel cell systems， and the present work aims to fill thisvoid． Experimental data are reported for the first time to show the effects of different gas diffusionlayer materials and contact pressure on the electrical contact resistance． A fractal asperity based model is adoptedto predict the contact resistance as a function of pressure， materialproperties， and surface geometry． Good agreement is observed between thedata and the model predictions for a wide range of contacting pressures andmaterials．

Fig． 1 （a） Schematic of a PEM fuel cell，  （b） enlarged view showing the flow channel plate and the gas diffusion layer  interface， and （c） close up view of the interface showing the roughness of  the contacting surfaces

Fig． 2 （a） Profilometric scan of the  surface of GDL－10BA gas diffusion layer， and （b） surface asperity height  along the x－direction

Profilometric： 轮廓测定法

asperity：表面粗糙

核心公式：

别的不会，告诉自己偷懒的话直接公式3、4拟合算了。

Fig． 3 （a） Photograph and （b） schematic  of the contact resistance measurement setup

Table 1 Parameters of the gas diffusion  layers considered in the study

Table 2 Porosity and through－thickness  bulk resistivity values for the gas diffusion layers and the bipolar plate

Fig． 4 Compressive stress as a function  of compressive strain for GDL－10BA， in the thickness direction

Fig． 5 Variation of （a） total resistance  and （b） contact resistance with contact pressure for the GDL－10BA cloth－based  gas diffusion layer in contact with a graphite bipolar plate

Table 3 Compressive modulus as a function  of the pressure range for GDLs

Fig． 6 Variation of the bulk resistances  of GDL－10BA and graphite， and the interfacial contact resistance between  them， with contact pressure

Fig． 7 Variation of the measured contact  resistance over a range of pressure for all the gas diffusion layer samples evaluated

Fig． 8 Structure function obtained from  the profilometric scan （Fig． 2） for a GDL－10BA gas diffusion layer sample

这里是双对数坐标。

Table 4 Fractal dimension and topothesy  values for the contacting GDL／bipolar plate surfaces at two extreme compaction  pressures

topothesy：形貌系数

Fig． 9 Comparison of experimental data  with fractal model prediction on the contact resistance， for all the GDL  samples and contact pressure considered

在较高的压强下，实验和理论预测挺相符。

Conclusions

A systematic study on the measurement of  electrical contact resistance between gas diffusion layers and graphite  bipolar in a PEM fuel cell was presented． Measured contact resistances are

reported over a range of clamping pressure  for various paper－based and cloth－based gas diffusion layers． The measured  contact resistance values were compared with the predictions of a contact resistance  model based on a fractal representation of the interface geometry． Good  agreement was demonstrated between the model predictions and measured values  for all the materials and pressures considered． Unlike the contact between rigid asperity surfaces， the contact  resistance between the rigid graphite plate with a soft gas diffusion layer  surface was found to be dependent on the compressive modulus of the softer  material． It was found that in general， the paper－based gas diffusion layers have higher values of contact  resistance as compared to those of the cloth－based gas diffusion layers．  The results of the present study can be used in a comprehensive simulation  model of a PEM fuel cell to account for the effect of interfacial contact  resistance on the cell performance．

In the original model， interfacial contactis only caused by the deformation of surface asperities and the bulk materialsare considered to be rigid．

做燃料电池注定了你不会出类拔萃，但必定与众不同。

小编专注独自阅读，这里无翻译，向世界散播虚情假意。