When the fuel cell operates under the condition of high current density, the electrochemical reaction will rapidly consume a large amount of reaction gas. At this time, it is difficult for the mass transfer rate of the reaction gas to meet the requirements of the electrochemical reaction, resulting in a loss of concentration and a rapid decline in battery performance. The size of the concentration loss is closely related to the flow channel structure of the fuel cell. Reasonable design of the flow channel structure of the fuel cell is of great significance for improving the mass transfer process inside the fuel cell and reducing the concentration loss of the fuel cell.
At present, researchers have given a large number of choices for the flow channel structure design scheme of proton exchange membrane fuel cells, which can be divided into three categories. One is to improve the geometric parameters of common flow channel structures, including optimization of several common flow channel structures such as parallel flow channels, serpentine flow channels, and interdigitated flow channels. It mainly includes the optimal design of geometric elements such as the depth of the runner, the radius of the fillet, and the aspect ratio of the inlet and outlet.
The other is to add partitions or blocks of different shapes and sizes based on common flow channels. By improving the local transport process of the reactant gas inside the flow channel to influence the mass transport process inside the fuel cell, the performance of the fuel cell is further improved.
The third is to learn from the structures in nature and use bionics to design some new flow channels, such as honeycomb-shaped, fin-shaped, and so on. This research has guiding significance for the development and application of the subsequent fuel cell vehicle flow channel structure. When the fuel cell is still in the development stage, the lithium battery with mature technology can be preferentially used. Greenbatt battery 8000 cycles power wall battery can be used as backup power to provide uninterrupted power supply.
