The characterization of proton exchange membrane fuel cell electrodes is essential for understanding the electrode performance. In this paper, mercury intrusion porosimetry and the nitrogen adsorption method were used to measure pore size distributions and porosities (ϵ) of various electrodes, which were made with either platinum supported on amorphous carbon (Pt/VA) or platinum supported on graphitized carbon (Pt/VG), and had ionomer‐to‐carbon weight ratios (I/C) of 0.5, 1.0, and 1.5. The oxygen effective diffusivity ($ D_{{\rm O}_2}^{\rm eff} $) in electrodes was measured as a function of relative humidity (RH) in an apparatus that was previously described [Z. Yu, R. N. Carter, J. Power Sources 195 (2010) 1079–1084]. The tortuosity of electrodes at the dry condition (80 °C and 0% RH) was then determined from the measured porosities and $ D_{{\rm O}_2}^{\rm eff} $. For a given catalyst, as the I/C ratio increased, it was found that the electrode's mean pore size, porosity, and $ D_{{\rm O}_2}^{\rm eff} $ all decreased, but the tortuosity increased. For a given I/C ratio, the Pt/VA electrode exhibited larger mean pore size, larger porosity, larger $ D_{{\rm O}_2}^{\rm eff} $, and smaller tortuosity compared with the Pt/VG electrode. The contrast between Pt/VA and Pt/VG electrodes with the same I/C ratio indicates different ionomer distribution on the catalyst surface.

In this paper, a supply and demand matching algorithm for industry park level energy systems is proposed. The algorithm can provide the configuration scheme of distributed generators installed capacity in line with the given load demand. Comprehensively considering the output characteristics of distributed sources such as wind and photovoltaic generators in different timeframes, the outputs of distributed generators are classified into several typical modes, and the installed capacity of distributed generator is matched in line with the representative output mode and the load demand curve so as to realize the balance of energy supply and demand in the industry park. The energy storage device is used to balance the energy due to the asynchronism of the distributed generator output and the load demand. The capacity requirements of the battery under various installed capacities of distributed generators are provided. The proposed algorithm is programmed in MATLAB and verified by the actual data of an industry park in northeast China. The results show that the proposed algorithm can comprehensively consider the output characteristics of distributed generator in different time ranges, and provide reasonable matching schemes of energy supply.