【摘要】 为获得高性价比的商业化AB5型贮氢合金,研究了以Cu代替部分Co对Mm(NiMnAl-SiFe)4.2-4.7Co0.65-xCux(x≤0.38mol)合金的电化学性能的影响.实验结果表明,Cu添加量为0～0.38mol时,其最大放电比容量Cmax由352.7mA.h/g降至310.9mA.h/g,高倍率放电性能HRD2520由65.82%降至34.13%;合金充放电循环300次,容量保持率S300由81.89%降至62.58%;合金的初始活化次数为2～3次,氢平台区则变窄,吸氢平台压先上升而后下降.Cu添加量为0.10mol时,合金具有较好的性价比:Cmax=333.2mA.h/g,HRD2520=60.27%;容量保持率为80%时,循环寿命为346次;吸氢平台压为0.082MPa,最大吸氢量可达1.00%.更多还原

【Abstract】 In order to obtain highly cost-effective AB5type hydrogen storage alloys,the electrochemical property of alloys Mm(NiMnAlSiFe)4.2-4.7Co0.65-xCux(x≤0.38mol)were studied though increasing partial substitution content of Co by Cu.The electrochemical studies showed that during the Cu addition increased from 0to 0.38mol,the maximum discharge capacity(Cmax)of these alloys decreased from 352.7 to 310.9mA.h/g,the high rate discharge ability HRD2520decreased from 65.82%to 34.13%,the cycling stability(C300/Cmax)of the alloy electrodes decreased from 81.89%to 62.58%.Further,the P-C-T curves of these alloys were tested,and the results showed that the number of activation was 2-3times,with hydrogen platform areas narrowing,and platform pressures of hydrogen firstly increasing and then decreasing.All the experiments results showed that with 0.10mol Cu addition,the alloy had a good quality-price ratio and its electrochemical properties showed as following:the maximum discharge capacity of this alloy was 333.2mA.h/g,the HRD2520was 60.27%,the cycling times was 346with 80% of capacity retention;platform pressure of hydrogen was 0.082 MPa,and the maximum content of hydrogen absorption was 1.00%.更多还原