Electrochemical characterization of absorbed hydrogen in stoichiometric and nonstoichiometric hydrogen storage alloys

Inoue, Hiroshi; Miyamoto, Masayoshi; Matsuoka, Makoto; Fukumoto, Yukio; Iwakura, Chiaki

doi:10.1016/s0013-4686(96)00254-x

Cited by 8 publications

(6 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These data a i 0 values were normalized on the basis of the total alloy weight in the electrode, which results in mA g −1 as its unit instead of the conventional unit of mA cm −2 , because the MH electrode is porous in nature and its actual surface area cannot be measured exactly, leading to unpredictable errors. are close to the results obtained by other workers 10,17,21 for similar hydrogen storage alloy electrodes.…”

Section: Mh Ads Mh Abs ͓2͔supporting

confidence: 92%

“…Recently, many kinds of hydrogen storage alloys have been developed to be widely used as the negative electrodes for the Ni/MH battery [1][2][3] and new electrocatalysts for hydrogen evolution in alkaline water electrolysis. 4,5 It is well known that the performances of the hydrogen storage alloy electrodes and metal hydride ͑MH͒ electrodes are largely dependent on the alloy composition, [6][7][8] stoichiometric ratio x of the Mm͑B 5 ͒ x alloys, [9][10][11][12][13][14] surface properties of the alloys, [15][16][17][18][19][20] and environment temperature. [21][22][23] Until now, various electrochemical parameters in MH electrodes have been widely investigated [21][22][23][24][25] but only a few researchers [26][27][28][29] have reported the MH performances as a function of temperature.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Effects of Temperature on the Performance of the MmNi[sub 3.6]Co[sub 0.7]Mn[sub 0.4]Al[sub 0.3] Metal Hydride Electrode in Alkaline Solution

Sequeira

Chen

Santos

2006

J. Electrochem. Soc.

View full text Add to dashboard Cite

In the present study, the electrochemical and hydrogen transport kinetic performance of the MmNi3.6Co0.7Mn0.4Al0.3 metal hydride electrode has been systematically investigated in the temperature range 0–60°C . The results show that the electrode reaction becomes more reversible and gets faster at higher temperatures. At low-discharge current densities, the charge transfer overpotential is greater than the diffusion overpotential, whereas at high-discharge current densities the diffusion overpotential becomes dominant. At medium-discharge current densities, there is a mixed control with a predominance of the mass-transport conditions at lower temperatures. The calculated kinetic parameters also show that the hydrogen desorption on the metal hydride electrode is easier than the hydrogen absorption into its alloy bulk. Activation energies for charge transfer and for hydrogen diffusion, as well as the hydrogen diffusion coefficients in the electrode, have also been estimated.

show abstract

Section: Mh Ads Mh Abs ͓2͔supporting

confidence: 92%

mentioning

confidence: 99%

Effects of Temperature on the Performance of the MmNi[sub 3.6]Co[sub 0.7]Mn[sub 0.4]Al[sub 0.3] Metal Hydride Electrode in Alkaline Solution

Sequeira

Chen

Santos

2006

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

“…Recently, many kinds of hydrogen storage alloys have been developed to be widely used as the negative electrodes for the Ni/MH battery [1][2][3] and new electrocatalysts for hydrogen evolution in alkaline water electrolysis [4,5]. It is well known that the performance of the hydrogen storage alloy electrodes and metal hydride (MH) electrodes are largely dependent on the alloy composition [6][7][8], stoichiometric ratio x of the Mm(B 5 ) x alloys [9][10][11][12][13][14], surface properties of the alloys [15][16][17][18][19][20] and environment temperature [21][22][23].…”

Section: Introductionmentioning

confidence: 99%

Anodic Polarisation Characterisation of Absorbed Hydrogen in Modified Mm(B5)x Alloys

Santos

Chen

Sequeira

2009

DDF

View full text Add to dashboard Cite

Anodic polarisation curves of Mm(Ni3.6Co0.7Mn0.4Al0.3)x (Mm = mischmetal, 0.85  x  1.15) electrodes were measured under the conditions of various initial concentrations of absorbed hydrogen (H/M), potential sweeping rates (v), temperatures (T), and amounts of reducing agent (y = [NaBH4]) in alkaline solution. Anodic peak current (Ip) at the Mm(B5)x electrodes increased with an increase in T, x and y values. In addition, the Ip value depended linearly on initial hydrogen concentration and square root of potential sweeping rate, irrespective of T, x and y values. Furthermore, the activation energy for hydrogen diffusion decreased with an increase in x and y values. From these results, it is considered that the surface reduction treatment of the Mm(B5)x alloys, performed in alkaline solution with sodium borohydride, the nonstoichiometry and the initial concentration of absorbed hydrogen, are important factors for improving the charge-discharge performance of negative electrodes for metal-hydrogen energy systems.

show abstract

“…A relevant way to estimate the rate-determining step is the comparison of the activation energies for both of these two processes. In several reports, the activation energy for these two processes on MmNi 5-x M x (M = Co, Mn and Al) alloy electrode has been evaluated with the aim to find the optimal alloy composition [8,9]. On the other hand, Senoh et al [10] determined the activation energies for each of these two processes occurring on MmNi 3.6 Co 0.7 Mn 0.4 Al 0.3 alloy electrode in alkaline solution in order to estimate the rate-determining step.…”

Section: Introductionmentioning

confidence: 99%

Electrochemical Study of Hydrogen Electrode Reaction Kinetics on LmNi3.55Co0.75Mn0.4Al0.3 Alloy Electrode

Potkonjak¹,

Sužnjević²,

Simonović³

et al. 2005

MSF

View full text Add to dashboard Cite

The exchange current density and the peak current density of the hydrogen electrode reaction on LmNi3.55Co0.75Mn0.4Al0.3 alloy electrode in an aqueous 1M KOH solution, at low hydrogen contents (<0.1 H/M) and elevated temperatures (42-60°C), were studied using potentiostatic polarization techniques. Both measured quantities increased linearly with the increase in hydrogen content in the alloy. On the basis of the difference between the activation energy of the charge transfer and the hydrogen diffusion, it was concluded that the charge transfer reaction represented the rate-determining step of the hydrogen electrode reaction under applied experimental conditions. The decrease of each of these two activation energies with increasing hydrogen content was evidenced, which indicated the existence of other processes occurring in the electrode bulk accompanying the hydrogen diffusion.

show abstract

Electrochemical characterization of absorbed hydrogen in stoichiometric and nonstoichiometric hydrogen storage alloys

Cited by 8 publications

References 4 publications

Effects of Temperature on the Performance of the MmNi[sub 3.6]Co[sub 0.7]Mn[sub 0.4]Al[sub 0.3] Metal Hydride Electrode in Alkaline Solution

Effects of Temperature on the Performance of the MmNi[sub 3.6]Co[sub 0.7]Mn[sub 0.4]Al[sub 0.3] Metal Hydride Electrode in Alkaline Solution

Anodic Polarisation Characterisation of Absorbed Hydrogen in Modified Mm(B<sub>5</sub>)<sub>x</sub> Alloys

Electrochemical Study of Hydrogen Electrode Reaction Kinetics on LmNi<sub>3.55</sub>Co<sub>0.75</sub>Mn<sub>0.4</sub>Al<sub>0.3</sub> Alloy Electrode

Contact Info

Product

Resources

About