Study on the phase structures and electrochemical performances of La0.6Gd0.2Mg0.2Ni3.15-xCo0.25Al0.1Mnx (x=0-0.3) alloys as negative electrode material for nickel/metal hydride batteries

The preparation of negative electrodes for nickel-metal hydride (Ni-MH) batteries using a La0.7Mg0.3Al0.3Mn0.4Co0.5Ni3.8 alloy in the as-cast state has been carried out. The alloy was mechanically crushed (<44 m) and a battery was manufactured with this material. The mean discharge capacity achieved using this method was 384 mAh/g. Another two batteries were prepared using a hydrogen powdered La0.7Mg0.3Al0.3Mn0.4Co0.5Ni3.8 alloy at low and high pressures (2-10 bar). It has been shown that hydrogen powdering facilitates the activation of the negative electrode for Ni-MH batteries. This study also included the characterization of the hydrogenated and crushed powders. These materials were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD).

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Development of a Liquid Immersion-Type Nickel-Metal Hydride Battery Under High-Pressure

Journal of The Electrochemical Society ◽

10.1149/1945-7111/ac3c22 ◽

2021 ◽

Author(s):

Kouji Maeda ◽

Shinji Yae ◽

Naoki Fukumuro ◽

Kenji Iimura ◽

Ayumu Matsumoto

Keyword(s):

High Pressure ◽

Metal Hydride ◽

High Pressures ◽

Negative Electrode ◽

Nickel Metal ◽

Nickel Metal Hydride ◽

Electric Capacity ◽

Discharge Cycle ◽

Mh Battery ◽

Charge Discharge

Abstract A nickel-metal hydride (Ni–MH) prototype battery completely immersed in an aqueous electrolyte solution of KOH under high pressure was fabricated to examine the effects of high pressure on the quality of Ni–MH batteries. The small battery cell comprised positive and negative electrode materials, as used in electric vehicles, and an Ag/AgO reference electrode. The electric capacity of the Ni–MH battery was measured at different temperatures and pressures with small currents and charge/discharge voltages of 1.6 – 1.0 V. High pressures were found to clearly and effectively enhance the electric capacity of the Ni–MH battery at larger currents. The considerable effect of high pressure on the Ni–MH battery was elucidated by the change in internal resistance during the charge/discharge cycle life experiment, indicating that the voltage of the positive electrode did not appreciably change at a high pressure compared to that of the negative electrode. Moreover, the use of large currents in rapid charge/discharge cycle tests at high pressures of up to 30 MPa resulted in charge/discharge cycles that were five times faster and a quick recovery of capacity was achieved in the 0.5 – 2.1 V range.

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Raman and X‐Ray Photoelectron Spectroscopic Investigations on a New Electrode Material for Nickel‐Metal Hydride Batteries: MgNi‐Graphite Composites Prepared by Ballmilling

Journal of The Electrochemical Society ◽

10.1149/1.1391822 ◽

1999 ◽

Vol 146 (5) ◽

pp. 1659-1663 ◽

Cited By ~ 20

Author(s):

Chiaki Iwakura ◽

Hiroshi Inoue ◽

Shu G. Zhang ◽

Shinji Nohara ◽

Kenshi Yorimitsu ◽

...

Keyword(s):

Metal Hydride ◽

Electrode Material ◽

Nickel Metal ◽

Nickel Metal Hydride ◽

X Ray ◽

Spectroscopic Investigations ◽

Graphite Composites

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Effect of Doped Metal Ions on the Electrochemical Performance of Nickel Hydroxide Electrode for Nickel/Metal Hydride Battery

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.2942 ◽

2013 ◽

Vol 448-453 ◽

pp. 2942-2945

Author(s):

Xiao Rui Gao ◽

Kang Le Jiang ◽

Yu Qiao Wang ◽

Yong Jing Hao

Keyword(s):

Metal Ions ◽

Metal Hydride ◽

Nickel Hydroxide ◽

Electrochemical Performances ◽

Nickel Metal ◽

Exchange Method ◽

Nickel Metal Hydride ◽

Proton Diffusion ◽

Nickel Metal Hydride Battery ◽

Hydride Battery

Positive materials for nickel/metal hydride battery, nickel hydroxide doped by different metal ions were synthesized by coprecipitation, and subsequent hydrothermal treatment and anion exchange method. The structure of the samples was analyzed by XRD test, and the electrochemical performances were studied by galvanostatic charge-discharge, cyclic voltammetry and impedance tests. The obtained electrode material shows mainly β-Ni (OH)2structure when only doping Zn2+, while α-Ni (OH)2structure was obtained by only doping Al3+or co-doping Al3+and Zn2+. Ni (OH)2co-doped Al3+and Zn2+had fine cyclic stability, high number of exchanged electrons per nickel atom (the maximum is 1.93), small charge-transfer and proton-diffusion resistances.

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