Development of a Micro Temperature Sensor and 3D Temperature Analysis for a Proton Exchange Membrane Fuel Cell

This study examines the development of micro in situ sensors and analyzed the through-plane temperature of a fuel cell. Temperature sensing inside a fuel cell is important in fuel cell diagnosis and analysis. Temperature sensors must be adequately small, so that fuel cell performance is maintained and the temperature anywhere inside the cell can be flexibly measured. In this study, a temperature sensor based on a micro-electromechanical system (MEMS) is designed and fabricated to achieve these objectives. The micro temperature sensor was installed inside a cell to measure through-plane temperature. The current and voltage of the fuel cell with the micro temperature sensor were measured and compared with those of a fuel cell without the sensor to analyze the effect of the sensor on fuel cell performance. The developed temperature sensor is of resistance temperature detector (RTD) type, with a flexible substrate of polyimide, high sensitivity, and easy installation characteristics. After calibration of the sensors, three sensors were inserted into the cell to measure the through-plane temperature, and the polarization curve of the cell with and without the micro sensor was compared. Finally, a 3D computational fluid dynamics (CFD) model of a fuel cell was developed and analyzed by comparison of the measured temperature results to determine the accuracy of the model.