In this work a detailed analysis of the overpotentials inherent during the operation of a solid oxide fuel cell (SOFC) is presented. The study is performed in order to evaluate the effect of the design of the current collectors on SOFCs performance. The analysis is carried out by means of numerical simulations in different current collector configurations consisting of straight channels in which their width is varied. Special attention is paid in the ohmic and concentration losses which are directly related with the design of the current collectors. Polarization and power density curves are obtained for different current collector designs operating at the same conditions. The ohmic losses were directly affected by the ratio between the gas channels-electrode interface area and the active area. Increasing or decreasing the area ratio around a certain value causes the ohmic losses to increase exponentially. Moreover, the concentration losses showed an opposite behavior when compared with the ohmic losses. The best performance was obtained when the ratio between the gas channels-electrode interface area and the active area is about 0.36.

在这项工作中，将对固体氧化物燃料电池（SOFC）运行期间固有的过电势进行详细分析。进行研究是为了评估集电器设计对SOFC性能的影响。该分析是通过数值模拟在不同的集电器配置中进行的，这些集电器配置包括宽度变化的直通道。要特别注意与集电器设计直接相关的欧姆和浓度损失。对于在相同条件下运行的不同集电器设计，可以获得极化和功率密度曲线。欧姆损耗直接受到气体通道-电极界面面积与有效面积之间的比率的影响。增大或减小某个特定值附近的面积比会导致欧姆损耗呈指数增长。而且，与欧姆损耗相比，浓度损耗表现出相反的行为。当气体通道-电极界面面积与有效面积之比约为0.36时，可获得最佳性能。