To this end, multiple strategies an

To this end, multiple strategies and material improvements have been made to help optimizewater management within PEMFCs. Research groups have investigated reactive control strategies via signal analysis and the manipulation of operating conditions [5]. Hussaini et al. [6] demonstrated a dynamic external intermittent humidification scheme using a single serpentine flow field, as well as a multiple, parallel channel flow field. Song et al. [7] investigated the connection between the hydrogen pressure drop with the development of cathode flooding within a fuel cell and proposed a hydrogen purge scheme, along with humidification modification, as a water management scheme for an operating PEMFC. Damour et al. [8] developed a control scheme for an air flow controller to regulate membrane humidity and optimize PEMFC performance. Pahon et al. [9] proposed a signal-based fault diagnostic approach using relative wavelet energy to analyze signals from a 40-cell stack toidentify abnormal or healthy operation. These signal-based approaches are based on reacting to a change in the voltage or pressure signal to identify the beginning of the flooding condition, and then modifying the flow conditions, namely the relative humidity (RH) of the flow streams, to move the fuel cell away from the flooded state. Research has also been done on the modification of material properties and structure of various PEMFC components.