The multi-physics dynamic coupling mechanism of proton exchange membrane fuel cell (PEMFC) is the core challenge of performance optimization. In this paper

an electro-thermal-gas normalized collaborative modeling method is proposed

which combines electrochemical reaction

heat transfer and gas transmission mechanisms

and combines energy conservation to construct a multi-physical field coupling model. The response quantification index (RQI) is presented to quantify the dynamic response intensity and phase difference through the longitudinal amplitude range

which breaks through the limitations of traditional time analysis. The voltage error rate of the model is less than 1.7% under steady/transient conditions

and the power output is highly consistent with the experimental data. The results show that the electrical response sensitivity is the highest (RQI is 4.65)

and the thermal response is significantly delayed due to thermal inertia (RQI is 0.44). The gas flow rate regulates the temperature and water balance through oxygen partial pressure and heat dissipation efficiency (RQI is 2.85)

revealing the coupling mechanism of current-driven heat production and gas consumption

thermal inertia-induced temperature hysteresis

and gas distribution reaction to electrical performance. The model provides theoretical support for the collaborative management and dynamic control optimization of heat and water. The RQI system establishes a unified evaluation framework for the dynamic response of multi-physical fields.