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In-Situ Measurement of Fuel Flow in Fuel Cell Using Flexible Micro Flow Sensors

Fuel cells are a highly promising alternative source of electrical power. However, this renewable energy source has various problems yet unsolved, such as the difficulty in determining fuel flow rate inside fuel cells. The product of the chemical reaction in a fuel cell is water, which reduces the working efficiency of a fuel cell and adversely affects the fuel flow rate. This study fabricates micro flow sensors on a flexible substrate using micro-electro-mechanical systems (MEMS) to monitor the fuel flow rate in fuel cells. Monitoring the distribution of the fuel flow rate can stabilize fuel cell performance by regulating the heater in real time. The micro flow sensors that were fabricated using this approach have the following advantageous characteristics: (1) they are small; (2) they are highly sensitive; (3) they are flexible and strong; and (4) they can be placed anywhere to make measurements in-situ.