Abstract
The proper functioning of the fuel cell system depends on the proper operation of all its subsystems. One of the key subsystems is the oxidant supply system, which is responsible for supplying oxygen for the electrochemical reaction taking place in the cell. It also transports the reaction products, i.e., water, outside the fuel cell stack, and in some cases removes excess heat generated in the stack. Changes in the technical condition of machine individual elements always result in changes in operating or residual parameters; however, it is necessary to select appropriate diagnostic methods to be able to use these changes to assess the machine’s technical condition. This article presents the results of research focused on assessing the possibilities of diagnosing the oxidant supply subsystem, in particular, too low an oxidant flow leading to oxygen starvation and cathode flooding, based on the analysis of the voltage occurring in individual cells of the stack as well as on the basis of vibration and acoustic emission (AE) measurements. The presented results show that the faulty operation of that system can be indicated either through electrical and vibroacoustic/acoustic emission measurements.