|Tipo di tesi||Tesi di laurea magistrale|
|Titolo||Elettrodeposizione Galvanica: Un Approccio Numerico|
|Titolo in inglese||Galvanic Electrodeposition: A Numerical Approach|
|Struttura||Dipartimento di Ingegneria "Enzo Ferrari"|
|Corso di studi||Ingegneria Del Veicolo (D.M.270/04)|
|Data inizio appello||2022-02-08|
|Disponibilità||Accessibile via web (tutti i file della tesi sono accessibili)|
L'attività presentata in questo lavoro è focalizzata sul processo di elettrodeposizione galvanica.
The activity presented in this work focuses on the galvanic electrodeposition process. This process was chosen because it’s strictly related to charge and discharge cycles which can be observed in Li-ion batteries typical of modern BEVs, PHEVs and FCEVs. The process has been studied via multi-physics simulations based on mathematical models describing its characteristic phenomena. Copper deposition has been chosen due to the simple environment that can return important results that can lead to further improvements in battery electrodes. The goal is to estimate the coating thickness and its distribution as a function of copper concentration, pores’ length, porosity, overpotential, temperature, fluid velocity and exchange current density to evaluate the behavior of the system in different environments. Simulations were carried out in order to compare different geometries and environments in terms of computational time, in order to evaluate the feasibility of the simulations. Simplified 2D models were created starting from electrodes’ porous surface. An increase in temperature and concentration led to an increase in layer thickness; a higher over-potential returned an increase in layer thickness and a spiky profile if overpotential rose above a threshold level related to the pore’s geometry and a higher exchange current density returned a different deposition profile with higher thickness near the pores’ entrance but lower thickness deeper in the pore. The pores’ L/ϕ ratio influences the deposition process, reducing the amount of material deposited with longer pores and modifying the effects that come with the variation of different parameters. Pores’ position (in both absolute and relative terms) has its influence too: a lower pore density lead to a slight increase in material deposited in order to compensate for the higher mutual distance between pores. Effects of fluid motion of the electrolyte solution can be considered negligible in laminar regime for geometries with long pores due to the absence of convection inside the pores. Thermal gradients, instead, returned an increase in deposited layer thickness that can go up to 12.2% with a 10°C temperature difference between the two electrodes. Increased complexity of the simulation leads to increased computational times: with complex multi-physics simulations (i.e. Fluid-Dynamics and Heat Transfer simulations) simplified geometries have been adopted.