球磨法制备Ni-Mn-Zn三元氢氧化物及电化学性能

Preparation of Ni-Mn-Zn hydroxide by ball milling and its electrochemical property

为了降低二次碱性电池正极氢氧化镍的成本,采用球磨法制备出Mn代氢氧化镍[Ni1-xMnx(OH)2,x=0～0.3]。X射线衍射测试证实其为β-Ni(OH)2的结构。恒电流充放电试验表明,Ni1-xMnx(OH)2电极的放电电位和容量随Mn取代量的增加而逐渐降低;而Zn部分取代镍[Ni0.8Mn0.2-yZny(OH)2,y=0～0.075]能够提高电极的放电电位。与市售的球形氢氧化镍相比,球磨法制备的Ni0.8Mn0.15Zn0.05(OH)2电极在循环伏安曲线中出现Ni-Mn-O复合物的还原峰,且峰电位低于NiOOH的还原峰电位,两种电极的0.2 C容量和循环性能接近,但后者的大电流性能更佳。

In order to reduce the cost of nickel hydroxide for alkaline secondary battery, Mn substituted nickel hydroxide [Ni1-xMnx（OH）2, x=0-0.3] was prepared by a simple ball milling method. The results of X-ray diffraction tests indicate that it has a structure of β-Ni（OH）2, but both the discharge potential and capacity of the Ni1-xMnx（OH）2 electrodes shows decrease with the increase in the substitution amount of Mn. On the contrary, the substitution of Zn for Ni results in an increase in the discharge potential of the Ni0.8Mn0.2-Zny（OH）2 （y= 0-0.075） electrodes, Compared to commercial Ni （OH）2 in spherical shape, the cyclic voltammogram of the ball milled Ni0.8Mn0.15n0.06（OH）2 electrode shows the reduction of a Ni-Mn-O composite which has a lower reduction potential than NiOOH. Both has a similar capacity at a 0.2 C rate and cycling durability, but the ball milled Ni0.8Mn0.15Zn0.05（OH）2 electrode has better high-power performance than the former.