Improvement of MC Method in SAE J2601 Hydrogen Refuelling Protocol Using Dual-zone Dual-Temperature Model

The MC method refuelling protocol in SAE J2601 has been published by the Society of Automotive Engineers (SAE) in order to safely and quickly refuel hydrogen vehicles. For the calculation method of the pressure target to control the refuelling stop, we introduced a dual-zone dual-temperature model that distinguishes the hydrogen temperature in the tank from the wall temperature to replace the dual-zone single-temperature model of the original MC method. The total amount of heat transferred by convection between hydrogen and the inner tank wall during the filling process was expressed as an equation of final hydrogen temperature, final wall temperature, final refuelling time, tank inner surface area and the correction factor. The correction factor equations were determined by fitting simulation data from the 0D1D model where hydrogen inside the tank is lumped parameter model (0D), and the tank wall is a one-dimensional model (1D). For the correction factor of the linear equation, its first-order coefficient and constant term have a linear relationship with the initial pressure of the storage tank, and their R2 values obtained from the fitting are greater than 0.99. Finally, we derived a new equation to calculate the final hydrogen temperature which can be combined with the 100% SOC inside the vehicle tank to determine the pressure target. The simulation results show that the final SOC obtained are all greater than 96% using the modified pressure target and the correction factor of the linear equation.