Effect of supercapacitors directly hybridized with PEMFC on the component contribution and the performance of the system

Abstract

Hybridization of a fuel cell (FC) with energy storage systems such as supercapacitors (SC) or batteries can make the fuel cell withstand the sudden fluctuations of the current. Moreover, direct hybridization of a FC with SCs (i.e. without power converters) has further proved out to be a better solution than the indirect mode (i.e. with power converters), in addition without inducing further ageing of the cell in non-steady operations. The present investigation was aimed at comparing the performance of the system in terms of yield and the component contributions of the fuel cell and the supercapacitor in power conversion on increasing the capacity of energy storage. A single 100 cm 2 cell was directly hybridized to one or three 3000 F SCs in standard fuel cell dynamic load cycling operation, simulating the energy demand in urban transport with current varying in the range 0-100 A. Upon comparing the hydrogen supply for the two configurations (1 or 3 SC), increasing the SC number decreased the hydrogen amount required in a cycle by approximately 5 %. This also enhanced the yield of the fuel cell and the hybrid source by 10 % and 16 % respectively. Moreover, increasing the SCs capacity reduces the power supplied by the FC in periods with high energy demand in cycling tests.

Evaluation of fluctuating voltage topology with fuel cells and supercapacitors for automotive applications

“…To alleviate these drawbacks, supercapacitors are introduced to support FC in fluctuating voltage topology. Arora et al analyzes the performance of different numbers of supercapacitors (one or three) directly hybridized with FC and shows that increasing the supercapacitor numbers allows for a decrease in the hydrogen amount by approximately 5%, and this also enhances the yield of FC and reduces the power contribution of FC. In Wu et al, it is evident that the direct hybridized system reduces the dynamic load on the FC and also increases the hydrogen utilization efficiency.…”

The observation of supercapacitor effects on PEMFC–supercapacitor hybridization performance through voltage degradation and electrochemical processes

“…The catalyst degradation may be generated by Warburg diffusion because the reactant diffused onto the catalyst layer and into the porous catalyst support. These phenomena cause corrosion of the carbon support and/or platinum dissolution, corresponding to eqn (10)- (13).…”

“…Parameters such as voltage degradation rate, 12 power, energy, yield, and efficiency, are necessary to determine for consideration of the system performance. 13 These parameters can be determined based on the following equations:…”

Direct hybridization of PEMFC and supercapacitors: Effect of excess hydrogen on a single cell fuel cell durability and its feasibility on fuel cell stack

“…The fuel cell yield for the different configurations is presented in Figure 3. This yield is defined by the energy supplied by the fuel cell during the cycling operation in Wh over the fuel supplied to the fuel cell in normal liters (NL) of hydrogen [18]. This figure indicates that fuel cell alone at higher stoichiometry has the lowest yield when compared to the fuel cell hybrid configurations.…”