In the last years electric vehicles gained importance as a more sustainable alternative to traditional vehicles. The introduction of an electric powertrain leads to lower air-pollution emissions but it also involves the introduction of new materials in the product life cycle, e. g., the rare earths and lithium contained in the motor and in the batteries. Those materials have an environmental impact and they need to be disposed properly. The aim of this thesis is to have a quantitative knowledge of the environmental balance linked to the use of a different powertrain. Furthermore, this study explores how this balance can be modified improving the recycling and the end of life management. Specifically in this thesis, an average electric scooter has been chosen as a case study. The electric scooter is used as object of comparison with a traditional internal-combustion-engine scooter. The choice of a two-wheeled mean of transport is linked to the low level of facilities involved. This report first includes a definition of the case of study; this section also presents a description of the technologies taken into exam. It is also presented the result of interviews with dismantlers to depict the current process of EoL management of a scooter. The central part of thesis deals with different recycling scenarios. With the help of the Material Hygiene mind-set, a qualitative analysis and different recycling scenarios are proposed. The recycling scenarios involve the component of the electric powertrain that are peculiar of the electric vehicle. They mainly are the electric motor and the lithium battery pack. The last part of the analysis encompasses a Life Cycle Assessment of an average electric scooter to give a quantitative meaning to the life cycle comparison and to assess the environmental benefits of the proposed recycling scenarios. To perform the Life Cycle Assessment a software, SimaPro 7.3, is used. This software lets the user insert the bill of materials of the product and it associates to each material its environmental loads according to the database EcoInvent v.2.2. Keywords: electric scooter, lithium battery, permanent magnet, neodymium, Material Hygiene, Design for Disassembly, Life Cycle Assessment, LCA / Negli ultimi anni i veicoli elettrici sono emersi come un ’alternativa sostenibile ai veicoli tradizionali. L’introduzione di un gruppo propulsore elettrico permette emissioni inquinanti più basse ma comporta anche l’introduzione di nuovi materiali nel ciclo di vita del prodotto, e.g., le terre rare e il litio contenuti rispettivamente nel motore e nelle batterie. Questi materiali hanno un impatto ambientale e hanno bisogno di essere trattati correttamente. Lo scopo di questa tesi è di avere una comprensione quantitativa del bilancio dal punto di vista ambientale legato al l’adozione di sistema di propulsione elettrico. Inoltre, è indagato come questo bilanco possa essere influenzato migliorando il ricic laggio e la gestione dell’ultima fase di vita del prodotto. Nello specifico, in questa tesi, uno scooter elettrico è stato scelto come caso di studio. Lo scopo è di comparare questo scooter con uno tradizionale considerando il ciclo di vita del prodotto. Il mezzo di trasporto a due ruote è stato scelto perché considerato più semplice da modellare in quanto privo di componenti non inerenti al trasporto (es. aria condizionata, hi-fi, etc.). Questo report anzitutto include una definizione del caso di studio, questa sezione presenta anche una descrizione delle principali tecnologie coinvolte nel prodotto studiato. In questa parte del lavoro è anche riportato il risultato di interviste a rottamatori di scooter per illustrare l’attuale iter di rottamazione di uno scooter. La parte centrale della tesi tratta i differenti scenari di riciclaggio. Sfruttando la mentalità Material Hygiene vengono proposte un’analisi qualitativa e differenti scenari di rici claggio. Gli scenari di riciclaggio coinvologono il progettista a livelli differenti. Questi scenari riguardano i componenti del sistema di propulsione elettrico. Essi sono principalmente il motore elettrico e le batterie al litio. L’ultima parte dell’analisi riguarda il Life Cycle Assessment di uno scooter elettrico al fine di dare un significato quantitativo al confronto tra i cicli di vita delle due alternative. Inoltre, il life cycle assessment ha lo scopo di verificare e quantificare i benefici di impatto ambientale collegati all’adozione degli scenari di riciclaggio proposti. Per svolgere il Life Cycle Assessment è stato usato un sofware, SimaPro 7.3. Questo software permette all’utente di inserire l’elenco dei materiali di un prodotto e di associare a ciascun materiale il proprio impatto ambientale. Il software ha a disposizione per la modellazione i database di impatto ambientale EcoInvent 2.2. Parole chiave: scooter elettrico, batteria al litio, magnete permanente, neodimio, Material Hygiene, Design for Disassembly, Life Cycle Assessment, LCA

Porous carbons are promising anode materials for next generation lithium batteries due to their large lithium storage capacities. However, their highsloping capacity during lithiation and delithiation as well as capacity fading due to intense formation of solid electrolyte interphase (SEI) limit their gravimetric and volumetric energy densities. Herein we compare a microporous carbide derived carbon material (MPC) as promising future anode for all solid state batteries with a commercial high performance hard carbon anode. The MPC obtains high and reversible lithiation capacities of 1000 mAh g 1 carbon in half cells exhibiting an extended plateau region near 0 V vs. Li/Liþ preferable for full cell application. The well defined microporosity of the MPC with a specific surface area of >1500 m2 g 1 combines well with the argyrodite type electrolyte (Li6PS5Cl) suppressing extensive SEI formation to deliver high coulombic efficiencies. Preliminary full cell measurements vs. nickel rich NMC cathodes (LiNi0.9Co0.05Mn0.05O2) provide a considerably improved average potential of 3.76 V leading to a projected energy density as high as 449 Wh kg 1 and reversible cycling for more than 60 cycles. 7Li Nuclear Magnetic Resonance spectroscopy was combined with ex situ Small Angle X ray Scattering to elucidate the storage mechanism of lithium inside the carbon matrix. The formation of extended quasi metallic lithium clusters after electrochemical lithiation was revealed.

Depuis la mise en évidence des potentialités du phosphate LiFePO4 comme électrode positive de batteries lithium-ion, un très fort regain d’intérêt pour les phosphates de fer est actuellement observé. Dans cette optique de recherche de nouveaux matériaux, notre intérêt s’est porté sur la phase Na3Fe3(PO4)4 et sur des monophosphates de fer et de manganèse de type alluaudite LiXNa1-XMnFe2(PO4)3. Leurs structures, respectivement en couche et en chaines, en font de bons candidats pour des applications en tant que matériau d’électrode pour des batteries au lithium ou au sodium. Notre étude porte donc, d’une part, sur la synthèse et la caractérisation structurale de ces phases, et d’autre part sur leurs propriétés physiques et électrochimiques. / Since the discovery of highly interesting properties for LiFePO4 as a positive electrode material in lithium ion batteries, the search for novel polyanion-based insertion hosts is intense. Actually, cathodic materials based on iron phosphates exhibit high stability and economical and environmental interests. In this context, we were interested in Na3Fe3(PO4)4 with a lamellar structure and in alluaudite-like iron and manganese phosphates LiXNa1-XMnFe2(PO4)3 which structure exhibits tunnels. This work deals, in one hand, on the synthesis and the structural characterisation of these materials and in the other hand on their physical and electrochemical properties as positive electrode for lithium and sodium batteries.

Cette thèse se concentre sur la fiabilité des batteries lithium pour des applications véhicules à faible émission en CO2. Pour cela, des méthodologies de caractérisation électriques et thermiques, des protocoles et des tests de vieillissement de batteries lithium sous différents modes (cyclage actif, calendaire simple et cyclage/calendaire) ont été mis en œuvre.Une première partie de ces travaux de thèse s’attache à la modélisation et à l’estimation des états de charge et de santé de la batterie.La deuxième partie est consacrée à l’étude du vieillissement calendaire des batteries lithium utilisant la spectroscopie d’impédance comme méthode de caractérisation. Ensuite, une méthode originale pour l’évaluation de l’état santé de la batterie est proposée. Elle est basée sur l’exploitation de l’étape de charge à tension constante lors d’une recharge complète et est donc bien adaptée à une intégration au sein d’un système de gestion de batterie. L’approche introduite est validée sur des données réelles de vieillissement allant jusqu’à deux ans de test.Enfin, une étude du phénomène de régénération de la capacité suite à un vieillissement des batteries de type combiné cyclage/calendaire est menée. Cette dernière partie constitue une ouverture pour le développement de stratégies d’usage des batteries lithium en incluant leur comportement thermique. / In this thesis, we focus on the reliability of lithium batteries used for automotive applications. For this purpose, electric and thermal characterization methodologies as well as aging tests under several modes (calendar, power cycling, calendar/power cycling) are carried out.In a first part of the work, battery modeling and battery state estimation (state-of-charge and state-of-health) are considered.Then, based on periodic characterization from electrochemical impedance spectroscopy, calendar aging is investigated. Next, we proposed an original process for precise battery state-of-health determination that exploits a full recharge and mainly constant-voltage charge step which allows easily its integration within a battery management system. Our experimental results, up to two years real-life data, confirm effectiveness of our technique.Finally, we study the capacity recovery phenomenon occurring due to combined battery aging (calendar/power cycling). This final part is almost dedicated to introduce strategies for battery use presenting at the same time a thermal behavior study.

[pt] No Brasil, existem muitos projetos em sistemas fotovoltaicos, e a projeção para os próximos anos é de crescimento devido incentivos governamentais e os elevados preços das tarifas de energia. Associado a isso, o mercado de armazenamento de energia com baterias de íons de lítio tem se mostrado promissor devido a uma considerável queda nos preços dessas baterias nos últimos anos. Isso pode representar uma oportunidade para o mercado de sistemas fotovoltaicos quando os incentivos acabarem. Este trabalho propõe um modelo PLIM (Programação Linear Inteira Mista) estocástico para dimensionar um sistema fotovoltaico integrado com armazenamento de energia em baterias para grandes consumidores de energia, usando cenários de geração e consumo, podendo considerar diferentes modalidades tarifárias. As variáveis de decisão são o número de painéis, inversores, baterias, a operação diária do sistema de armazenamento e a demanda contratada do consumidor. A função objetivo busca minimizar o custo de investimento no sistema fotovoltaico, baterias e fatura de energia. A abordagem proposta será analisada sob diferentes premissas, uma com incentivos governamentais sobre a anergia injetada na rede e outra na qual a injeção de energia na rede não é permitida, a fim de avaliar a importância das baterias para manter a atratividade econômica do sistema fotovoltaico. Os resultados indicaram que o efeito sinérgico do sistema fotovoltaico com baterias potencializa a arbitragem, que está relacionada com a diferença entre as tarifas de energia de ponta e fora ponta. Isso ocorre principalmente com operação zero exportação porque somente assim o consumidor é livre para escolher a capacidade do seu sistema fotovoltaico, que hoje é limitado no Brasil quando o sistema é conectado na rede de distribuição. / [en] In Brazil, there are many projects in photovoltaic systems, and the projection for the coming years is positive due to the government incentives and the expensive energy tariffs. Associated with this, the Lithium-ion battery storage systems market has been promising due to a significant drop in battery prices in the last few years. This may represent an opportunity for the photovoltaic system market when the incentives run-out. This work proposes a stochastic mixed integer linear programming (MILP) model to design a photovoltaic system integrated with battery energy storage for big electricity consumers, using generation and consumption scenarios, being able to consider different Time-of-Use tariffs. The decision variables are the number of panels, inverters and batteries, its daily operation and the power demand contracted. The objective function aims to minimize the cost of investment, in the photovoltaic system, batteries and electricity bill. The proposed approach will be analyzed under different assumptions, one with the government incentive about injected surplus and another in which the injection into the network is not possible, in order to assess the importance of a storage system to keep the economic attraction of the photovoltaic system. Results indicated that the synergic effect of the photovoltaic system and battery potentialize the arbitrage, which is related to the difference between peak and off-peak energy tariff. This occurs, mainly with Zero Export operation because only this way the consumer is free to choose the capacity of the photovoltaic system, which is limited in Brazil when the system is allowed to inject energy into the network.