纳米结构球形β-Ni(OH)_2制备及高速充放电性能研究

Preparation of spherical nanostructured β-Ni(OH)_2 for high electrochemical performance

提出并分析了纳米结构球形β-Ni(OH)2的结晶环境,通过对反应液中氨水浓度和pH等因素的有效控制,合成了具有纳米结构的球形β-Ni(OH)2。借助FSEM、XRD和振实密度等测试手段对合成过程进行了综合考查,得出了合成具有纳米结构球形β-Ni(OH)2的最佳工艺条件。通过不同倍率下的恒流充放电实验表明,该球镍样品具有比现有普通球镍更好的电化学可逆性,在500～5000mA/g的高电流密度下给出了328.3～294.5mAh/g的比容量,并使镍电极的充电时间缩短到4.3min。

After proposing and analyzing nano-spherical β-Ni(OH)2 formation conditions,through the effective control of reaction factors such aqueous ammonia concentration and pH,etc.,spherical nanostructured β-Ni(OH)2 is synthesized.FSEM,XRD,and tap density tests are carried out to analyze and obtain the optimum conditions for synthesis of nanostructured spherical β-Ni(OH)2.The charge-discharge experiments under different multiple rates of constant current show that the specific capacity of this spherical nickel samples can reach 328.3-294.5 mAh/g at 500-5 000 mA/g of high current density,and nickel electrode charging time can be reduced to 4.3 min,which means it has better electrochemical reversibility than the common spherical nickel.