钒系储氢合金充放氢性能及其数据拟合研究

本文对氢燃料电池用钒基固溶体合金的充放氢性能及其吸附热力学、等温线及等温模型进行研究。采用P-C-T测试仪对钒系储氢合金进行活化并测试其充放氢性能,验证压力和温度对钒系储氢合金充放氢性能的影响,并在实验的基础上对其充放氢过程中所涉及到的吸脱附等温模型、热力学模型进行探讨。研究结果表明:钒系储氢合金在673 K、4 MPa的条件下可实现完全的活化,属于易活化类型储氢合金。在吸附反应第一阶段的吸附等温线拟合结果表明,从相关系数来看,钒系储氢合金的吸氢类型更接近Freundlich模型,热力学研究结果表明,钒系储氢合金的放氢过程为吸热反应。

Charging and Dehydrogenation Properties of Vanadium-based Hydrogen Storage Alloys and Data Fitting

In this paper,the hydrogen adsorbing-desorbing properties and adsorption thermodynamics,isotherm and isothermal model of vanadium-based solid solution alloys for hydrogen fuel cells are studied.P-C-T tester is used to test the hydrogen adsorbing-desorbing properties of vanadium-based hydrogen storage alloys after activation of them.The effects of pressure and temperature on the hydrogen adsorbing-desorbing properties of the alloys are verified.Based on the experiments,the adsorption-desorption isothermal model and thermodynamic model involved in the hydrogen adsorbing-desorbing processes are discussed.It is concluded that the V-based hydrogen storage alloys belong to the easy-to-activate hydrogen storage alloys and can be fully activated at 673 K and 4 MPa.The results of adsorption isotherm fitting in the first stage of adsorption reaction show that the hydrogen absorption type of the alloys is closer to Freundlich model from the correlation coefficient point of view.Meanwhile,the thermodynamic results show that the hydrogen evolution processes of the alloys are among endothermic reaction.