Advanced

In operando neutron diffraction study of LaNdMgNi9H13 as a metal hydride battery anode

Nazer, N. S.; Denys, R. V.; Yartys, V. A.; Hu, Wei Kang; Latroche, M.; Cuevas, F.; Hauback, Bjorn C.; Henry, P. F. LU and Arnberg, L. (2017) In Journal of Power Sources 343. p.502-512
Abstract

La2MgNi9-related alloys are superior metal hydride battery anodes as compared to the commercial AB5 alloys. Nd-substituted La2-yNdyMgNi9 intermetallics are of particular interest because of increased diffusion rate of hydrogen and thus improved performance at high discharge currents. The present work presents in operando characterization of the LaNdMgNi9 intermetallic as anode for the nickel metal hydride (Ni-MH) battery. We have studied the structural evolution of LaNdMgNi9 during its charge and discharge using in situ neutron powder diffraction. The work included experiments using deuterium gas and electrochemical charge-discharge measurements. The... (More)

La2MgNi9-related alloys are superior metal hydride battery anodes as compared to the commercial AB5 alloys. Nd-substituted La2-yNdyMgNi9 intermetallics are of particular interest because of increased diffusion rate of hydrogen and thus improved performance at high discharge currents. The present work presents in operando characterization of the LaNdMgNi9 intermetallic as anode for the nickel metal hydride (Ni-MH) battery. We have studied the structural evolution of LaNdMgNi9 during its charge and discharge using in situ neutron powder diffraction. The work included experiments using deuterium gas and electrochemical charge-discharge measurements. The alloy exhibited a high electrochemical discharge capacity (373 mAh/g) which is 20% higher than the AB5 type alloys. A saturated β-deuteride synthesized by solid-gas reaction at PD2 = 1.6 MPa contained 12.9 deuterium atoms per formula unit (D/f.u.) which resulted in a volume expansion of 26.1%. During the electrochemical charging, the volume expansion (23.4%) and D-contents were found to be slightly reduced. The reversible electrochemical cycling is performed through the formation of a two-phase mixture of the α-solid solution and β-hydride phases. Nd substitution contributes to the high-rate dischargeability, while maintaining a good cyclic stability. Electrochemical Impedance Spectroscopy (EIS) was used to characterize the anode electrode on cycling. A mathematical model for the impedance response of a porous electrode was utilized. The EIS showed a decreased hydrogen transport rate during the long-term cycling, which indicated a corresponding slowing down of the electrochemical processes at the surface of the metal hydride anode.

(Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Electrochemical impedance spectroscopy, In situ neutron diffraction, Lanthanum, Magnesium, Metal hydride, Neodymium
in
Journal of Power Sources
volume
343
pages
11 pages
publisher
Elsevier
external identifiers
  • scopus:85010430981
ISSN
0378-7753
DOI
10.1016/j.jpowsour.2017.01.077
language
English
LU publication?
yes
id
93af714e-3770-4d85-ac69-4e56dc310dc2
date added to LUP
2017-03-09 13:58:06
date last changed
2018-01-07 11:54:51
@article{93af714e-3770-4d85-ac69-4e56dc310dc2,
  abstract     = {<p>La<sub>2</sub>MgNi<sub>9</sub>-related alloys are superior metal hydride battery anodes as compared to the commercial AB<sub>5</sub> alloys. Nd-substituted La<sub>2-y</sub>Nd<sub>y</sub>MgNi<sub>9</sub> intermetallics are of particular interest because of increased diffusion rate of hydrogen and thus improved performance at high discharge currents. The present work presents in operando characterization of the LaNdMgNi<sub>9</sub> intermetallic as anode for the nickel metal hydride (Ni-MH) battery. We have studied the structural evolution of LaNdMgNi<sub>9</sub> during its charge and discharge using in situ neutron powder diffraction. The work included experiments using deuterium gas and electrochemical charge-discharge measurements. The alloy exhibited a high electrochemical discharge capacity (373 mAh/g) which is 20% higher than the AB<sub>5</sub> type alloys. A saturated β-deuteride synthesized by solid-gas reaction at P<sub>D2</sub> = 1.6 MPa contained 12.9 deuterium atoms per formula unit (D/f.u.) which resulted in a volume expansion of 26.1%. During the electrochemical charging, the volume expansion (23.4%) and D-contents were found to be slightly reduced. The reversible electrochemical cycling is performed through the formation of a two-phase mixture of the α-solid solution and β-hydride phases. Nd substitution contributes to the high-rate dischargeability, while maintaining a good cyclic stability. Electrochemical Impedance Spectroscopy (EIS) was used to characterize the anode electrode on cycling. A mathematical model for the impedance response of a porous electrode was utilized. The EIS showed a decreased hydrogen transport rate during the long-term cycling, which indicated a corresponding slowing down of the electrochemical processes at the surface of the metal hydride anode.</p>},
  author       = {Nazer, N. S. and Denys, R. V. and Yartys, V. A. and Hu, Wei Kang and Latroche, M. and Cuevas, F. and Hauback, Bjorn C. and Henry, P. F. and Arnberg, L.},
  issn         = {0378-7753},
  keyword      = {Electrochemical impedance spectroscopy,In situ neutron diffraction,Lanthanum,Magnesium,Metal hydride,Neodymium},
  language     = {eng},
  month        = {03},
  pages        = {502--512},
  publisher    = {Elsevier},
  series       = {Journal of Power Sources},
  title        = {In operando neutron diffraction study of LaNdMgNi<sub>9</sub>H<sub>13</sub> as a metal hydride battery anode},
  url          = {http://dx.doi.org/10.1016/j.jpowsour.2017.01.077},
  volume       = {343},
  year         = {2017},
}