摘要
为提高新型AB_3型储氢合金La_(0.94)Mg_(0.06)Ni_(3.49)Co_(0.73)Mn_(0.12)Al_(0.20)的电化学性能,将球磨法制备的Ni-B-C粉末按不同质量分数添加到合金中。采用X射线粉末衍射仪(XRD)和扫描电子显微镜(SEM)分析合金的相结构和表面形貌。结果表明,添加Ni-B-C粉末后,合金相结构没有变化,仍由LaNi_5相和La_2Ni_7相2个相组成,但合金表面出现了细小颗粒。添加Ni-B-C粉末后,合金电极的最大放电容量和放电容量保持率均提高。当添加质量分数为10%的Ni-B-C粉末后,电极的最大放电容量从346 mAh/g增加到363 mAh/g,50个循环后的放电容量保持率从70%提高到77%,交换电流密度I0与极限电流密度IL分别为106和987 mA/g。动电位极化测试表明,电极的抗腐蚀能力也有所增强。综上,Ni-B-C可以提高AB_3型储氢合金的综合电化学性能。
Ni-B-C powder prepared by ball milling was introduced to improve the electrochemical properties of new AB3-type hydrogen storage alloy La0.94Mg0.06Ni3.49Co0.73Mn0.12Al0.20. The phase structure and surface morphology of the alloy were investigated by X-ray diffraction(XRD)and scanning electron microscope(SEM). The results show that the alloy remains the original LaNi5 and La2Ni7 phases and some little particles appear on the surface of alloy after adding Ni-B-C. The addition of Ni-B-C improves the maximum discharge capacity and capacity retention rate.After adding a mass fraction of 10% Ni-B-C, the maximum discharge capacity increases from 346 mAh/g to 363 mAh/g, and the capacity retention rate after 50 cycles increases from 70% to 77%. The exchange current density I0 and the limiting current density IL reach 106 and 987 m A/g,respectively. Potentiodynamic polarization indicates that the corrosion resistance of the electrodes is enhanced. The Ni-B-C powder can improve the comprehensive electrochemical properties of the hydrogen storage alloy.
作者
黄红霞
于文婉
王成
肖阳
Huang Hongxia;Yu Wenwan;Wang Cheng;Xiao Yang(Guangxi Key Laboratory of Electrochemical and Magneto-chemical Functional Materials,Guilin University of Technology,Guilin 541004,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2019年第4期1325-1329,共5页
Rare Metal Materials and Engineering
基金
广西自然科学基金(2016GXNSFAA380201)
广西电磁化学功能物质重点实验室研究基金(EMFM20161103)
关键词
Ni-B-C
储氢合金
电化学性能
Ni-B-C
hydrogen storage alloy
electrochemical properties