A new type of hydrogen storage tank has been developed for fuel cell vehicles FCHV. The tank design is based on the 35MPa high-pressure cylinder vessel and the heat exchanger module including hydrogen absorbing alloy with high dissociation pressure is integrated in it. To hydrogen absorbing alloy, for example, Ti-Cr-Mn alloy with AB2 laves phase is applied. Its effective hydrogen weight capacity is 1.9 wt% and reaction enthalpy is −2 kJ/molH2. To optimize the heat exchanger, thermal analyzing method was developed to predict the amount of hydrogen absorption or desorption. The simulation consists of heat and mass balance. Heat balance is made by the hydrogen absorbing alloy, heat exchanger and coolant each other. Also reaction heat of the hydrogen absorbing alloy and compressed heat are considered. The reaction heat is calculated from the equation of reaction rate that is derived experimentally.
Furthermore, an additional simulation to predict the charging performance of on-board high-pressure MH tank system by the radiator cooling will be reported. With this simulation, it will become possible to make parameter studies to investigate how the operating conditions influence the performance of tank system.