## 5 Conclusions  
This paper proposes an integrated framework for optimizing component sizing and energy management in a fuel cell/battery hybrid passenger vehicle. The framework integrates fuel economy and system durability into a single objective function through a weighting coefficient. It examines the variation in costs under different weighting factors and considers the impact of component sizing by the DP algorithm. Furthermore, the  
Figure 9: Total costs under different battery prices and economic cost coefficients.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Method**} & \multirow{2}{*}{\begin{tabular}{c} **Economic Cost** \\ **(kg/100 km)** \\ \end{tabular} } & \begin{tabular}{c} **Fuel Cell** \\ **Degradation** \\ **(\%/100 km)** \\ \end{tabular} & \begin{tabular}{c} **Battery** \\ **Degradation** \\ **(\%/100 km)** \\ \end{tabular} & \
\begin{tabular}{c} **Total Cost** \\ **(kg/100 km)** \\ \end{tabular} &
\begin{tabular}{c} **Battery** \\ **Capacity** \\ **(Ah)** \\ \end{tabular} \\ \hline Weighting factor & 1.5679 & 0.0527 & 0.0877 & 34.7721 & 44 \\ Fuel economy only & 1.2668 & 0.9916 & 0.089 & 597.0159 & 22 \\ System durability only & 1.8122 & 0.0526 & 0.0869 & 34.9211 & 44 \\ Pareto for economic & 1.5534 & 0.0553 & 0.1047 & 36.2042 & 33 \\ Pareto for durability & 1.5739 & 0.0526 & 0.0765 & 34.7932 & 55 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Comparison of different strategies.  
effects of power prices on the optimal parameters are systematically investigated. The key findings are summarized as follows:  
1. Based on the NEDC, a battery capacity of approximately 44 Ah, a maximum fuel cell power of 80 kW, and a weighting factor of 0.5 achieve an optimal balance between fuel economy and system durability in light-duty fuel cell passenger vehicles. Total costs are reduced by 1% compared to selecting the optimal system durability using the Pareto frontier.
2. Increasing the battery capacity can effectively reduce the total operational costs of FCHVs by minimizing per kilometer battery degradation and providing sufficient dynamic power. However, once the battery capacity reaches a level sufficient to deliver optimal dynamic power, further increases in capacity lead to a higher price and weight, thereby raising the total costs.
3. The weighting factor significantly influences the trade-off between fuel economy and system durability costs by altering energy distribution strategies. As the weighting factor increases, fuel economy costs decrease while durability costs rise, and vice versa. This effect differs fundamentally from that of changing the battery capacity. At present, fuel economy and system durability are equally important considerations. However, as power source prices decrease in the future, system durability may become less critical for fuel cell hybrid systems, with fuel economy optimization emerging as the primary focus.  
Conceptualization, X.X. and S.Z.; methodology, X.X. and S.Z.; software, X.X.; validation, X.X.; formal analysis, X.X.; investigation, X.X., C.S., H.D., Y.T. and J.F.; resources, H.Y., S.B., S.Z. and G.L.; data curation, X.X.; writing--original draft preparation, X.X.; writing--review and editing, X.X., Y.T. and S.Z.; visualization, X.X.; supervision, X.X.; project administration, H.Y., S.B., S.Z. and G.L.; funding acquisition, H.Y., S.B., S.Z. and G.L. All authors have read and agreed to the published version of the manuscript.  
The authors would like to acknowledge the Guangdong Basic and Applied Basic Research Foundation (2024A1515030057) and Natural Science Foundation of Shandong Province (2022 HWYQ-018, ZR2023 ME198) for grants and support.  
Not applicable.  
The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.  
The authors declare no conflict of interest.