Ml_(1-x)Mm_x(Ni_(3.55)Co_(0.75)Mn_(0.4)Al_(0.3))充放电性能的研究

A STUDY ON CHARGE-DISCHARGE CHARACTERISTICS OF MULTICOMPONENT HYDROGEN STORAGE ALLOYS Ml_(1-x)Mm_x(Ni_(3.55)Co_(0.75)Mn_(0.4)Al_(0.3))

通过对已活化的Ml1-xMmx(Ni3.55Co0.75Mn0.4Al0.3)(x=0,0.1,0.2,0.3,0.4,0.5)合金进行30次大电流充放电循环并测试循环后的放电容量来研究Ml∶Mm比例及粘接剂对其充放电性能的影响.结果表明:Ml∶Mm比例和及粘接剂对合金充放电性能有显著影响.按充放电制度300mAh/g×1.2h,放电截止电位为-0.60V(vs.Hg/HgO)进行30个循环后,Ml0.7Mm0.3(Ni3.55Co0.75Mn0.4Al0.3)对应的合金容量衰减最少,放电容量平台的平均值最高,其C1/Cmax值为72.98%(Cmax:最大放电容量:C1∶30次循环后的放电容量),放电容量平台的平均值为80.55mAh/g.使用PVA做粘接剂相比CMC做粘接剂,合金的高倍率充放电性能循环稳定性要好.

Charge-discharge characteristics of activated hydrogen storage alloys Ml_1-x)Mm_x(Ni_3.55)Co_0.75)Mn_0.4)Al_0.3)) with different Ml-Mm ratio are investigated after 30 charge-discharge cycles of 1C,300 mAh/g are completed.Discharge capacities of the alloys are measured as C_1 on completion of the 30 cycles.Results show that Ml-Mm ratio has a prominent effect on charge-discharge characteristics.With the charge-discharge procedure prescribed as follows: I_c=300mAh/g×1.2h,I_d=300 mAh/g,interval between charge and discharge-5 min,and final discharge voltage--0.60 V(vs.Hg/HgO),alloy Ml_0.7)Mm_0.3)(Ni_3.55)Co_0.75)Mn_0.4)Al_0.3)) demonstrates desirable charge-discharge characteristics.Capacity reduction of the alloy is the least,and its capacity retention (C_1/C_max)) amounts to 72.98%.Besides,the average discharge capacity of the discharge capacity plateau is the highest-80.55 mAh/g.Furthermore,the initial activation cycles also show that alloy Ml_0.7)Mm_0.3)(Ni_3.55)Co_0.75)Mn_0.4)Al_0.3)) possesses excellent activation characteristics.