摘要
采用球磨复合加高温烧结处理（BMS）及机械复合加高温烧结处理（MMS）两种方法制备了纳米复合材料Zr0.9Ti0.1（Ni0.55V0.12Mn0.28Co0.05）20-x％Mg（x=10,20）。XRD、TEM-SAED分析结呆表明,BMS和MMS的复合储氢材料均是由MgCu2型立方结构的C15-Laves相AB2和密排六方结构的纯Mg构成,未发现两相之间的合金化效应。复合材料中的AB2和Mg都属于纳米晶体。电化学性能测试结果表明,复合材料MMS电极的最大放电容量为410mAh/g（x=10）,而BMS的最大放电容量为360mAh/g（x=20）。在高倍率下（≥10C）,BMS电极的容量衰减率明显小于MMS电极。BMS（AB2-10％Mg）电极的高倍率放电性能最好。电化学动力学特性是当高倍率（≥10C）放电时,电极反应控制步骤以电荷传输控制为主。但BMS（AB2-10％Mg）电极的反应特性却是电荷传输控制和氢扩散控制的联合协同作用,表现有高倍率放电容量。因此.新型纳米复合储氢材料既适用于高能量型MH/Ni动力电池更适合高功率型MH/Ni动力电池。
The nanocomposite hydrogen storage materials Zr0.9Ti0.1(Ni0.55V0.12 Mn0.28 Co0.05)2.0-x%Mg(x = 10,20)were prepared by two ways: ball-milling + high temperature sintering(BMS) and mechanical-milling + high temperature sintering( MMS). XRD and TEM-SAED analyses showed that their microstructures were composed of MgCu2-type cubic structure C15-laves phase and hexagonal structure Mg, both no alloying effect. In the composite materials, the grain size of AB2 and Mg was in nanometer-sized range. Their electrochemical performances show that the maximum discharge capacity of MMS electrodes was 410mAh/g, the maximum discharge capacity of BMS electrodes was 360mAh/g. In HRD(≥10C), the declining rates of BMS electrodes capacities were obviously lower than those of MMS, best was the HRD discharge performance of BMS( AB2-10% Mg)electrode. Their electrochemical kinetics characteristics showing, when HRD discharging (10C), the charge transportation control was leaded; however, BMS(AB2-10%Mg)electrode had a cooperative effect of the charge transportation control and the hydrogen-diffusion control and -showed HRD discharge capacity. Therefore, the advanced nanocomposite hydrogen storage materials were suitable for not only high-energy MH/Ni power batteries but also high-power MH/Ni power batteries.
出处
《电池》
CAS
CSCD
北大核心
2002年第z1期94-97,共4页
Battery Bimonthly
基金
国家863计划资助项目(715-004-0233)
973资助项目(G2000026403)
关键词
纳米复合储氢材料
AB2/Mg
高倍率放电性能
动力学特性
nanocomposite hydrogen storage materials
AB2/Mg
HRD discharge performances
kinetics characteristics
