纳米级氢氧化镍与微米级球形氢氧化镍性能比较

Performance comparison between nano-sized and micro-sized spherical nickel hydroxide

为开发高容量、高循环性能镍氢电池,分别使用共沉淀法和固相沉淀转化法,合成了微米级球形氢氧化镍和纳米级氢氧化镍,并对其结构、形貌以及电化学性能进行了对比研究.XRD谱图分析、充放电以及循环伏安测试结果表明,纳米级氢氧化镍比微米级球形氢氧化镍具有更高的电化学活性,而微米级球形氢氧化镍在可逆性、电极循环寿命方面比纳米级氢氧化镍具有更为优越的性能.纳米级氢氧化镍与微米级球形氢氧化镍掺杂使用可收到较好的效果.当纳米级氢氧化镍以质量分数为8%与微米级氢氧化镍掺杂使用时,放电容量提高了约9.6%,同时电极循环性能也得到了一定提高.

Micro-sized spherical and nano-sized nickel hydroxide were synthesized by using co-precipitation and precipitation transform methods respectively to develop Ni-MH battery with high specific capacity and cycle life performance, and their structures, morphology and electrochemical performance were compared by X-ray diffraction, charge discharge and cyclic voltammetry tests. Results show that nano-sized nickel hydroxide has higher electrochemical activity than that of micron-sized spherical nickel hydroxide. But the reversibility, cycle life performance of electrode of micron-sized spherical nickel hydroxide were much better. Results also show that the doping of nano-sized nickel hydroxide into micron-sized spherical nickel hydroxide has better effects compared with that without doping. For example, the discharge capacity is increased by 9.6 %, and cycle life performance of electrode is improved a lot by doping with nano-sized nickel hydroxide which mass fraction is 8 % in micron-sized spherical nickel hydroxide doped.