快淬对贮氢合金组织和电化学性能的影响

摘要

The influence of rapid quenching on the microstructure and theelectrochemical properties of hydrogen storage alloy Ml(NiCoAlMn)5 (Ml=Lanthanum-rich Michmetal) has been investigated by the methods of XRD and TEM and DTA and electrochemical test.The results show that the homogenization of constituents and the decrease of cell volume are main factors influencing electrochemical properties of rapidly quenched hydrogen storage alloy.The constituent homogenization of rapidly quenched alloy by the quenching rate of 10m/s is enough to improve charge-discharge cycling stability,and rapid quenching by that of more than 10m/s has not any more improvement of cycling stability,but decreases cell volume and discharge capacity,so rapidly quenched alloy by the quenching rate of 10m/s possesses the best compositive electrochemical properties in current research.%通过XRD、TEM、DTA分析和电化学实验，研究了快淬对贮氢合金组织和电化学性能的影响。研究表明，成分均匀性改善和单胞体积减小是影响快淬贮氢合金电化学性能的主要因素，其中，前者使充放电循环稳定性提高，后者使放电容量降低。在本研究中，快淬速度为10m/s时，合金成分的均匀性已较铸态有明显改善，更高的快淬速度并不能使成分的均匀性进一步大幅度提高，反而使单胞体积减小，因此，快淬速度为10m/s时，快淬合金的综合电化学性能最佳。