An alternative for the anode materials of nickel metal hydride batteries: an AB3-type La0.6Gd0.2Mg0.2Ni2.6Co0.3Al0.1 hydrogen storage alloy. Issue 19 (27th April 2020)

• Record Type: Journal Article
• Authors: Gao, Zhijie; Meng, Qingwu; Zhang, Ying; Zhang, Faliang; Luo, Yongchun; Li, Hai-Wen
• Is Part Of: Dalton transactions. Volume 49:Issue 19(2020)
• Page Start: 6312
• Page End: 6320
• Publication Date: 2020-04-27
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d0dt00774a
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : In this work, AB3 -type La0.6 Gd0.2 Mg0.2 Ni2.6 Co0.3 Al0.1 alloys with approximately single PuNi3 phase and PuNi3 -/Ce2 Ni7 -type multiphase were designed and characterized. Abstract : In order to satisfy the demand for the cyclic stability of commercial Ni-MH anodes, a PuNi3 -type La0.6 Gd0.2 Mg0.2 Ni2.6 Co0.3 Al0.1 alloy with excellent overall electrochemical properties was prepared by annealing the as-cast alloy sample at different temperatures for a week. The alloy had the highest PuNi3 -type content of 86.9 wt% (1073 K), which offered a capacity retention of 69.6% after 100 cycles. However, 23.7 wt% PuNi3 type phase of the alloy constantly converted into the Ce2 Ni7 type phase within a temperature increase of 50 °C, which improved the capacity retention by 12.1% under the same discharge capacity. We found that the addition of Gd did not change the stacked [LaMgNi4 ]/[LaNi5 ] superlattice and it maintained the structural stability of the crystal as well as its anti-corrosion, which is also a key factor to improve cyclic stability. These findings imply that alloys with both PuNi3 -type and Ce2 Ni7 -type multiphase structures can be considered as a new choice for hydrogen storage.