Reactivity of complex hydrides Mg2FeH6, Mg2CoH5 and Mg2NiH4 with lithium ion: Far from equilibrium electrochemically driven conversion reactions
SOUGRATI, Moulay Tahar
Réseau sur le stockage électrochimique de l'énergie [RS2E]
Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier [ICGM ICMMM]
Réseau sur le stockage électrochimique de l'énergie [RS2E]
Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier [ICGM ICMMM]
JUMAS, Jean-Claude
Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier [ICGM ICMMM]
< Reduce
Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier [ICGM ICMMM]
Language
en
Article de revue
This item was published in
International Journal of Hydrogen Energy. 2013, vol. 38, n° 11, p. 4798-4808
Elsevier
English Abstract
The electrochemical reaction of lithium ion with Mg2FeH6, Mg2CoH5 and Mg2NiH4 complex hydrides prepared by reactive grinding is studied here. Plateaus at an average potential of 0.25 V, 0.24 V and 0.27 V corresponding to ...Read more >
The electrochemical reaction of lithium ion with Mg2FeH6, Mg2CoH5 and Mg2NiH4 complex hydrides prepared by reactive grinding is studied here. Plateaus at an average potential of 0.25 V, 0.24 V and 0.27 V corresponding to discharge capacities of 6.6, 5.5 and 3.6 Li can be achieved respectively for Mg2FeH6, Mg2CoH5 and Mg2NiH4. From in situ X-ray diffraction (XRD) characterizations of complex hydride based electrodes, dehydrogenation leads to a decrease of the intensities of the diffraction peaks suggesting a strong loss of crystallinity since formation of Mg and M (M = Fe, Co, Ni) peaks is not observed. 57Fe Mössbauer spectroscopy confirms the formation of nanoscale Fe or an amorphous Mg-Fe alloy during the decomposition of Mg2FeH6. Interestingly, lattice parameter variations suggest phase transitions in the Mg2NiH4 system involving the formation of low hydrogen content hydride Mg2NiH, while an increase of lattice parameters of Mg2CoH5 hydride could be attributed to the formation of a Mg2CoH5Lix solid solution compound up to x = 1.Read less <
English Keywords
Complex hydrides
Conversion reactions
Lithium ion batteries
Origin
Hal imported