Microstructure and electrochemical characteristics of Mm(Ni,Co,Mn,Al)5Bx (x=0–0.4) hydrogen storage alloys prepared by cast and rapid quenching

Effect of substituting B for Ni on electrochemical kinetic properties of AB5-type hydrogen storage alloys for high-power nickel/metal hydride batteries

“…Ye et al [17] found that the HRD of the over-stoichiometry MmNi 3.55 Co 0.75 Mn 0.4 Al 0.3 B x (x = 0, 0.05, 0.1, 0.2, 0.3) hydrogen storage alloys increased as the increase of the B content. The same results were obtained by Zhang et al [18] in the study of microstructure and electrochemical characteristics of over-stoichiometry Mm(Ni,Co,Mn,Al) 5 B x (x = 0-0.4) hydrogen storage alloys. Whether the HRD will gradually increases as the augment of B content is unknown.…”

“…A lot of research has focused on the partial replacement of La with Ce, Pr, Nd, Mg, Li, Ca and Ni with Fe, Al, Sn, Mn, etc. [11][12][13][14][15][16] or the additions of certain elements such as B [17][18][19] to improve the HRD of AB 5 -type hydrogen storage alloys. The addition of B element has been proved to be effective.…”

Phase structure and electrochemical properties of La0.7Ce0.3Ni3.75Mn0.35Al0.15Cu0.75−x(Fe0.43B0.57)x hydrogen storage alloys

“…The oxidation film becomes thick with the increase of x value, which is unfavorable to activation property. Fortunately, the formation of the secondary phase increases the number of phase boundaries, which provides extra tunnels for the diffusion of hydrogen atoms and is buffer area of the releasing of the stress formed in the process of hydrogen absorbed [8,13]. The increase of La 3 Ni 13 B 2 secondary phase causes the increase in the phase boundary, which can decrease the lattice distortion and strain energy formed in the process of hydrogen absorption.…”

“…Furthermore, some work focuses on improving the HRD of AB 5 -type hydrogen storage alloys by introducing B in the alloy. Zhang et al [8] have investigated low Co AB 5 -type MmNi 3.8 Co 0.4 Mn 0.6 Al 0.2 B x alloys composed of CaCu 5 -type main phase and a small amount of CeCo 4 B-type secondary phase and pointed out that the addition of B improved cycling stability and activation performance, high rate discharge capability. The substitution of B for Ni in MmNi 3.70−x Mn 0.35 Co 0.60 Al 0.25 B x alloys has been studied and found that the alloys with B had LaNi 5 phase and the secondary phase with CeCo 4 B-type structure, which improved the activation ability 0925-8388/$ -see front matter © 2011 Elsevier B.V. All rights reserved.…”

Microstructures and electrochemical hydrogen storage characteristics of La0.7Ce0.3Ni4.2Mn0.9−xCu0.37(Fe0.43B0.57)x (x = 0–0.20) alloys

“…Ye et al [13] reported that the addition of B modified the activation performance and significantly improved the highrate capacity of Mm 3.55 Co 0.75 Mn 0.4 Al 0.3 B x alloy though the electrochemical capacity was lower than that of commercial Mm 3.55 Co 0.75 Mn 0.4 Al 0.3 alloy. Zhang et al [14] pointed out that the addition of B improved the cycling stability, high rate discharge capability and discharge voltage for MmNi 3.8 Co 0.4 Mn 0.6 Al 0.2 B x alloys. Obviously, the addition of B element is effective to enhance activation performance and high-rate dischargeability.…”