(1. 中南大学 粉末冶金国家重点实验室， 长沙 410083；
2. 长沙矿冶研究院, 长沙 410012)
摘 要: 提出了2种β-球形氢氧化镍颗粒内切面扫描电镜（SEM）样品的制备方法。 X射线衍射(XRD)和SEM分析表明： β-球形氢氧化镍微观结构由大致相同的放射状的片晶叠合组成， 而片晶大小、球粒外表面形貌是其结晶有序程度的反映； 结晶有序性差的微细粒状微晶氢氧化镍较结晶有序性好、 粗粒片状氢氧化镍具有更好的电化学性能。 探讨了β-球形氢氧化镍微观结构的形成机制, 认为球粒形貌及结晶有序度可能与氢氧化镍的晶相从α→β的陈化程度有关： 随陈化程度的加深， 球粒表面微粒形貌从边界模糊的粒状向边界清晰的六方片状转化， 球粒内部晶片变大， XRD特征值（101）面半高宽和晶胞参数c变小， In/It增大。
关键字: MH-Ni二次电池； β-球形氢氧化镍； 微结构； 电化学活性； 陈化
（1. State Key Laboratory for Powder Metallurgy,
Central South University,Changsha 410083，China;
2. Changsha Research Institute of Mineral and Metallurgy,
Changsha 410012, China）
Abstract:Two methods to prepare the samples for the study of the interior morphologies of spherical β-Ni(OH)2 by scanning electronic microscopy(SEM) were developed. The microstructures of the spherical β-Ni(OH)2 with different exterior morphologies were characterized. The sizes of the crystal faces and the exterior morphologies of spherical β-Ni(OH)2 were associated with the structure regularity characterized by X-ray diffraction(XRD). It is indicated that the spherical β-Ni(OH)2 with poorly structure regularity exhibits better electrochemical activities than that with better structure regularity. The microstructure is supposed to be related to the ageing process from α-Ni(OH)2 to β-Ni(OH)2. With the ageing process, morphologies of the spherical β-Ni(OH)2 may change from the particle-like to the layer-like and the interior crystalline faces might become larger with the phase change for Ni(OH)2.
Key words: MH-Ni rechargeable battery; spherical β-Ni(OH)2; microstructure; electro-chemical activity; ageing
