镨含量对(La,Pr,Nd)Ni_(3.5)Co_(0.8)Mn_(0.4)Al_(0.3)合金电化学性能的影响

Effect of Praseodymium Content on Electrochemical Properties of (La,Pr,Nd)Ni_(3.5)Co_(0.8)Mn_(0.4)Al_(0.3) Alloys

目前广泛采用的镍-金属氢化物电池负极材料多为LaNi5基合金。本实验研究了稀土中镨含量分别为0、10％、20％、30％、40％的5种（La，Pr，Nd）Ni3.5Co0.8Mn0.4Al0.3合金的电极性能。发现稀土中镨含量为20％和30％的合金比其它成分的合金具有更高的放电容量，更好的电极稳定性。选用镨含量为17％的富镧混合稀土制备了成分为MlNi3.5Co0.8Mn0.4Al0.3的电极合金，并用这种合金组装了电池。测试结果表明，这种电池具有容量高、大电流放电性能好、循环寿命长和低温放电性能优异等特点，各项指标均超过国家标准。

The alloys adopted as nickel-metal hydride negative electrode material are almost LaNi5-based alloys now. In this study, the electrochemical properties of five types of (La,Pr,Nd)Ni3.5Co0.8Mn0.4Al0.3 alloy which Pr content in rare earth raw metal was respectively 0, 10%, 20%, 30%, 40% were studied. It was found that the alloys produced from rare earth raw metal with 20% or 30% Pr had higher discharge capacities and better durabilities than the other alloys. Using the rare earth with 17% Pr, we developed MINi3.5Co0.8Mn0.4Al0.3 electrode alloy. The batteries made by using this alloy as negative material had high energy density,excellent high rate discharge character, long cycle lifetime and excellent low temperature discharge character.