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

在本研究中，通过使用10 cm^2电极表面积的固体聚合物膜制造小型简单电池，将电池温度从室温改变到80 ℃，将电流密度调节到约1 A/cm^2，将燃料和氧化剂利用率和水电解率作为操作参数，定量地获得燃料电池和水电解电池的电池特性。为了分析实验结果，编制了考虑质量、能量、电荷平衡的二维数值计算程序。然而，活化和电阻过电压，和电渗系数是实验所需的。在对燃料电池的分析中，燃料电极侧的水蒸气随着质子转移而向氧化剂侧移动，燃料电极侧的水蒸气减少，聚合物膜干燥，离子电导率和电流密度降低。在下游，氧化剂侧中的水蒸气浓度增加，并且变为饱和状态，并且水蒸气向燃料电极侧进行反向扩散，并且膜均匀地变湿并且电流密度变为恒定。在分析水的电解时，只要电解水不短缺，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、能斯特电动势和电流密度在流动方向上都是恒定的。为了确认分析结果，通过分裂电极池测量电流密度分布。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.