Filters
Results 1 - 1 of 1
Results 1 - 1 of 1.
Search took: 0.024 seconds
Abdelghani-Idrissi, Soufiane
Universite PSL, Ecole doctorale no. ED 397 - Physique et chimie des materiaux, ESPCI, UMR 8231 Chimie, Biologie Innovation, Paris (France); EDF les Renardieres, Laboratoire des materiels electriques, Equipe de recherche M29 (France)2020
Universite PSL, Ecole doctorale no. ED 397 - Physique et chimie des materiaux, ESPCI, UMR 8231 Chimie, Biologie Innovation, Paris (France); EDF les Renardieres, Laboratoire des materiels electriques, Equipe de recherche M29 (France)2020
AbstractAbstract
[en] The fast charge of metal-air batteries represent one of the main scientific and technical challenges facing this technology. Oxygen bubbles formed during the charge process has a negative impact on the performances of the cells. Using flowing electrolyte for the evacuation of oxygen bubbles leads to a decrease of the electric potential of the gas evolving electrodes. For a given current, the electrode has more active surface, decreasing its potential. Optical measurement under microscope shows the bimodal distribution of the bubbles sizes. This repartition trends to a unimodal distribution when the flow rate of the electrolyte increases. Those electrochemical and optical characterizations bring information to develop an analytical modelling for the predictions of the dynamic behavior of these systems. A numerical simulation is also proposed to complete the analytical model. This simulation is able to reproduce the oscillatory behavior at high currents. The optimization of the energy efficiency of the process is done by calculating and choosing an optimal flow rate, corresponding to the best balance between the power gained and the hydraulic power consumed by the flow. The decrease of the hydraulic power needed is done by the adaptation of the geometry of the flow cells. Triangular configuration for the inlet and outlet zones of the flow are tested and shows better characteristics for natural and forced evacuation of the bubbles. A preliminary study and outlooks of the effect of flowing electrolyte on zinc dendrites are presented. Flowing electrolyte increase the time before short-circuit. (author)
[fr]
La charge rapide des batteries metal-air represente un des verrous technologiques auguel cette technologie est confrontee. Pour repondre a cette problematique, l'electrolyte est soumis a un ecoulement pour evacuer les bulles d'oxygene sources d'affaiblissement de l'efficacite de ces batteries. L'ecoulement de l'electrolyte permet une reduction du potentiel des electrodes a degagement de gaz. L'electrode presente une surface active plus elevee reduisant son potentiel electrique pour un courant donne. La microscopie optique met en evidence le caractere bimodal de la repartition de la taille de bulles qui tend vers une repartition monomodale lorsque le debit augmente. Ces caracterisations electrochimiques et optiques apportent les informations pour developper un modele analytique pour la prediction du comportement dynamique de ces systemes. Ce modele est complete par une simulation numerique qui met en evidence les phenomenes oscillatoires mesures a forts courants. L'optimisation energetique du procede est realisee par le choix d'un debit optimal qui concilie le gain en puissance electrique et les pertes de charges hydrauliques. La diminution des pertes par l'adaptation de la geometrie de la cellule d'ecoulement a ete abordee. La cellule a configuration triangulaire permet une double optimisation energetique. Ces cellules ont ete testees experimentalement et presentent de meilleures caracteristiques en termes d'evacuation naturelle et forcee des bulles. Une etude preliminaire et les perspectives de l'effet de l'ecoulement sur les dendrites de zinc sont presentees. L'ecoulement de l'electrolyte dans la cellule augmente le temps de court-circuit. (auteur)Original Title
La charge rapide d'une batterie metal-air par la maitrise de la fluidique diphasique
Primary Subject
Source
19 Oct 2020; 223 p; 136 refs.; Available from the INIS Liaison Officer for France, see the INIS website for current contact and E-mail addresses; These Docteur de l'Universite PSL, Specialites: Physico-chimie, Electrochimie et fluidique
Record Type
Miscellaneous
Literature Type
Thesis/Dissertation
Report Number
Country of publication
BUBBLE GROWTH, CHEMICAL REACTION KINETICS, COMPUTERIZED SIMULATION, CURRENT DENSITY, DENDRITES, ELECTRIC POTENTIAL, ELECTRODEPOSITION, ELECTRODES, ENERGY EFFICIENCY, FLOW RATE, LEAST SQUARE FIT, OSCILLATIONS, OVERVOLTAGE, PARAMETRIC ANALYSIS, PRESSURE DROP, TRIANGULAR CONFIGURATION, TWO-PHASE FLOW, VISCOSITY, ZINC-AIR BATTERIES
CONFIGURATION, CRYSTALS, DEPOSITION, EFFICIENCY, ELECTRIC BATTERIES, ELECTROCHEMICAL CELLS, ELECTROLYSIS, ENERGY STORAGE SYSTEMS, ENERGY SYSTEMS, FLUID FLOW, KINETICS, LYSIS, MATHEMATICAL SOLUTIONS, MAXIMUM-LIKELIHOOD FIT, METAL-GAS BATTERIES, NUMERICAL SOLUTION, REACTION KINETICS, SIMULATION, SURFACE COATING
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue