Thermohydrodynamic Basic Research on Characteristic Improvement of Water Electrolysis and Hydrogen Fuel Cell by Solid Polymer Film

在本研究中，采用电极表面积为10 cm^2的固体聚合物薄膜制作小型简单电池，将电池温度从室温调至80 C，将电流密度调至1 a /cm^2左右，以燃料和氧化剂利用率、水电解率为运行参数，定量获得了燃料电池和水电解电池的电池特性。为了对实验结果进行分析，生成了考虑质能、电荷平衡的二维数值编码。然而，在实验上对活化和抗过电压以及电渗透系数有一定的要求。在对燃料电池的分析中，燃料电极侧的蒸汽随着质子转移向氧化剂侧移动，燃料电极侧的蒸汽减少，聚合物膜干燥，离子电导率和电流密度下降。在下游，氧化剂侧蒸汽浓度增加，达到饱和状态，蒸汽向燃料电极侧反扩散，膜均匀湿润，电流密度趋于恒定。在水的电解分析中，水的汽化和熵热流向恒温的集电板，与燃料电池相比，整个膜的温度、能势电动势和电流密度在流动方向上都是恒定的，只要电解不缺水。为了验证分析结果，采用分离式电极槽测量了电流密度分布。除电流密度较大的区域外，分析结果与实测结果吻合较好。

In this study, the cell characteristics of fuel cell and water electrolysis cell was quantitatively obtained by a manufacture of small simple cell using solid polymer film of 10 cm^2 electrode surface area, changing the cell temperature from room temperature to 80ﾟC, adjusting the current density to be about 1 A/cm^2, making the fuel and oxidizing agent utilization rate and water electrolysis rate to be operating parameters. The two-dimensional numerical code considering a balance of mass and energy, electric charge was produced in order to analyze the experimental result. However, the activation and resistance overvoltage, and the electroosmosis coefficient were experimentally required. In the analysis of the fuel cell, the steam in the fuel electrode side moved to the oxidizing agent side with proton transfer, and the steam in the fuel electrode side decreased, and the polymer membrane dried, and the ionic conductivity and the current density decreased. In the downstream, the steam concentration in the oxidizing agent side increased, and became the saturation state, and the steam did the back-diffusion to the fuel electrode side, and the film uniformly got wet and the current density became to be constant. In the analysis of electrolysis of water, the water vaporization and entropy heat flowed to the power collection board of constant temperature, and the temperature of whole film, the Nernst electromotive force and the current density became to be constant in the flow direction in contrast to the fuel cell, as long as there was no shortage of the water for the electrolytic. The current density distribution was measured by way of a split electrode cell in order to confirm the analysis results. Except for the region of which current density was big, the analytical and measured result agreed well.