钙对(LaCa)-Y-Ni系储氢合金电化学循环稳定性的影响  

Effect of Calcium on Electrochemical Cycling Stability of(LaCa)-Y-Ni-Based Hydrogen Storage Alloy

作　　者：张旭 王利[1] 李宝犬 熊玮[1] 李金[1] 闫慧忠[1] Zhang Xu;Wang Li;Li Baoquan;Xiong Wei;Li Jin;Yan Huizhong(State Key Laboratory of Bai-yunobo Rare Earth Resource Researches and Comprehensive Utilization,Baotou Research Institute of Rare Earths,National Engineering Research Centre of Rare Earth Metallurgy and Functional Materi-als,Inner Mongolia Key Laboratory of Rare Earth Functional Materials,Baotou 014030,China)

机构地区：[1]包头稀土研究院白云鄂博稀土资源研究与综合利用国家重点实验室,稀土冶金及功能材料国家工程研究中心,内蒙古自治区稀土功能材料重点实验室,内蒙古包头014030

出　　处：《中国稀土学报》2022年第1期87-95,I0003,共10页Journal of the Chinese Society of Rare Earths

基　　金：国家重点研发计划项目(2018YFE0124400);国家自然基金项目(51961002);内蒙古自然科学基金项目(2020MS05013);白云鄂博稀土资源研究与综合利用国家重点实验室青年基金项目(2020Z2219)资助。

摘　　要：采用真空感应熔炼法制备La_(1-x)Ca_(x)Y_(2)Ni_(10.9)Mn_(0.5)(x=0~0.2)储氢合金薄带,在Ar气氛下1148 K热处理16 h,研究少量Ca元素对合金电化学性能及容量衰减的影响。结果表明:Ca元素促进合金中Ce_(5)Co_(19)相的形成,合金电极的最大放电容量下降,高倍率性能得到显著提升,x=0.2时,HRD_(3000)=64.64%,循环稳定性获得改善。合金在电解液中的腐蚀与溶解是影响循环性能的主要因素,合金粉化为次要因素,Ca元素的加入提高了合金的耐腐蚀性能,降低了合金电荷转移电阻,但同时也增加了合金的粉化程度。(LaCa)-Y-Ni系储氢合金容量的衰减是腐蚀与粉化综合作用的结果。La_(1-x)Ca_(x)Y_(2)Ni_(10.9)Mn_(0.5)(x=0~0.2)hydrogen storage alloy flakes were prepared by vacuum induction quenching furnace with a rotating copper wheel and annealed at 1148 K for 16 h in Ar atmosphere.The effect of trace Ca element on the electrochemical properties and degradation of discharge capacity of the alloy was investigated.With the addition of a small amount of Ca element,the alloy produces a new Ce_(5)Co_(19) phase in the A_(2)B_(7) phase,the maximum discharge capacity was greatly reduced,the HRD and the cycling stability of the alloy was significantly improved,the HRD_(3000)=64.64%at x=0.2.The intense oxidation/corrosion and dissolution of the alloy is the determinant factor of cycling capacity retention,while the alloy pulverization is the secondary factor,Ca element improves the corrosion resistance and reduces the charge-transfer resistance of the alloy,but also increases the degree of pulverization of the alloy.The result of(LaCa)-Y-Ni-based hydrogen storage alloy capacity degradation is the integrated role of oxidation/corrosion and pulverization.

关 键 词：La-Y-Ni系储氢合金 Ca元素 电化学性能 容量衰减 

分 类 号：TG139.7[一般工业技术—材料科学与工程]