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This work presents novel modeling and experimental techniques that provide insight into liquid-phase mass transport and electron transfer processes in lithium-ion batteries. These included liquid-phase ionic mass transport (conduction and diffusion), lithium diffuion in the solid phase and electronic transport in the solid phase. Fundamental understanding of these processes is necessary to efficiently design and optimize lithium-ion batteries for different applications. To understand the effect of electrode structure on the electronic resistance of the cathode, we tested power performance of cathodes with combinations of three different carbon conductivity additives: vapor-grown carbon fibers (CF), carbon black (CB) and graphite (GR). With all other factors held constant, cathodes with a mixture of CF+CB were found to have the best power-performance, followed by cells containing CF only and then by CB+GR. Thus, the use of carbon fibers as conductive additive was found to improve the power performance of cells compared to the baseline (CB+GR). The enhanced electrode performance due to the fibers also allows an increase in energy density while still meeting power goals. About one-third of the available energy was lost to irreversible processes when cells were pulse-charged or discharged at the maximum rate allowed by voltage-cutoff constraints. We developed modeling and experimental techniques to quantify tortuosity in electrolyte-filled porous battery structures (separator and active-material film). Tortuosities of separators were measured by two methods, AC impedance and polarization-interrupt, which produced consistent results. The polarization-interrupt experiment was used similarly to measure effective electrolyte transport in porous films of cathode materials, particularly films containing lithium iron phosphate. An empirical relationship between porosity and the tortuosity of the porous structures was developed. Our results demonstrate that the tortuosity-dependent mass transport resistance in porous separators and electrodes is significantly higher than that predicted by the oft-used Bruggeman relationship. To understand the dominant resistances in a lithium battery, we developed and validated a model for lithium iron phosphate cathode. In doing so we considered unique physical features of this active material. Our model is unusual in terms of the range of experimental conditions for which it is validated. Various submodel and experimental techniques were used to find physically realistic parameters. The model was tested with different discharge rates and thicknesses of cathodes, in all cases showing good agreement, which suggests that the model takes into account physical realities with different thicknesses. The model was then used to find the dominant resistance for the tested cathodes. The model suggests that the inter-particle contact resistance between carbon and the active-material particles was a dominant resistance for the tested cathodes.

Planning of distribution grids is based on statistically estimating the maximum load that will occur given a certain range of criteria (location, household types, district / electric heating etc.) Charging of electric vehicles is not one of these criteria. However, given the expected `boom' in sales of Chargeable Electric Vehicles (CEVs), and the lengthy planning process of distribution grids (>10 years) the knowledge gap is becoming a more pressing issue. This research has been conducted to investigate if Vattenfall, a Swedish electric utility company with distribution assets in both Sweden and Germany, needs to take action to react to the expected increase in CEVs in the near term. The study has been conducted with Uppsala Municipality as a showcase and 2030 as the time frame. The findings of this study show that Vattenfall should incorporate CEV usage into distribution planning to avoid overload of power stations in Uppsala by 2030. The ndings shows that 1) we can expect a 'boom' in sales of CEVs in the near future and that 73% of cars in trac in Uppsala may be CEVs by 2030 and 2) that CEV charging is expected to have a signi- cant impact on the distribution grid, with certain power stations in Uppsala seeing a peak load increase of up to 30%. The recommended actions are the following: • Monitor specific areas with a high concentration of cars and low energy consumption per household that already have substations with capacity below the recommended dimensions • Monitor CEV sales to reevaluate current projections on CEV development in Uppsala • Monitor trends of car ownership and evaluate whether this will aect CEV charging behaviour • Reconstruct Velander constants, used for grid planning, to take the CEV load into consideration • Investigate smart charging solutions, to shift the CEV load peak to a different time of the day / Dimensionering av distributionsnat baseras pa att statistiskt uppskatta den maximala lasten som kommer att intraa pa natet, givet olika faktorer (geograskt lage, hushallstyp, fjarrvarme / elvarme etc.). Laddning av elbilar ar inte en av de faktorer som man tar hansyn till. Givet en vantat kraftig okning av laddningsbara bilar, samt den langa planeringshorisonten for distributionsn at (>10 ar), blir dock fragan hur elbilar kommer att paverka elnatet valdigt aktuell. Denna studie har bedrivits for att avgora hur Vattenfall, ett statligt, svenskt elbolag med distributionsnat i Sverige och Tyskland, behover agera for att anpassa sig till den forvantade okningen av elbilar. Den har studien har genomforts som en fallstudie pa Uppsala Kommun med ar 2030 som tidsram. Resultaten fran studien visar att Vattenfall bor ta hansyn till laddning av elbilar vid dimensionering av distributionsnat for att undvika overbelastning pa natstationer i Uppsala ar 2030. Resultaten visar dels att 1) man kan forvanta sig en kraftig okning av forsaljning av laddningsbara fordon inom en snar framtid och uppemot 73 % av alla bilar i trak i Uppsala kommer att vara laddningsbaraar 2030 samt att 2) laddningsbara fordon kommer att ha en signikant paverkan pa distributionsnatet med okningar pa upp till 30 % av maxlasten for vissa natstationer. Foljande atgarder rekommenderas saledes: • Overvaka specika omraden med hog biltathet och lag energianvandning per hushall som ar anslutna till natstationer som ar underdimensionerade • Folj utvecklingen av forsaljning av laddbara fordon for att omvardera genom forda projektioner over laddningsbara bilar i Uppsala • Overvaka trender inom bilagande och utvardera hur detta paverkar laddningsbeteende • Gor om Velanderkonstanter sa att de tar hansyn till lasten fran laddbara fordon vid planering av elnat •  Utvardera smarta laddningslosningar for att ytta last fran elbilsladdning till en annan tidpunkt pa dygnet

The electrification of the transportation sector plays an important role in the sustainability transition as successful electric vehicle (EV) integration allows for the reduction of CO2 emissions. Moreover, bidirectional capabilities of the EVs (vehicle-to-grid) further facilitate this transition by supporting the electricity grid while lowering the cost of ownership of EVs when revenues from grid-supporting services are split between stakeholders. Due to sustainability challenges facing several domains, fundamental transformation processes are needed to transition away from our current global energy system. However, with the strong inertia of the current system together with the sheer complexity and vexed interests during transitions, neither private markets nor government agencies seem likely to spur this transition on their own. Transitions are thus political processes, in which standards can play an important role since they point to the direction of the transition. This thesis investigates the role of standardization in sustainability transitions. The aim was to improve the understanding of the diverse stakeholder attitudes towards the standardization process of the communication protocol between the vehicle and its charging equipment. While exploring this topic, the thesis further aimed to investigate the power relations that govern the interactions and coordination efforts between the diverse stakeholders involved in the vehicle-to-grid (V2G) standardization processes. To achieve this, a qualitative study was conducted where two transcripts from the California Energy Commission, adding up to a total of 667 pages, were coded in a mixed inductive-deductive manner. In addition, as a complement, 13 expert interviews were conducted. The results showed that power was expressed by actors on (and between) all levels in the system. Mutual dependency was the most frequently expressed power relation among the actors. The mutual dependency was assumed to be widely present due to the interdependent nature between the components in the V2G system. The automotive manufacturers were observed to have a strong position in the vehicle-to-grid ecosystem and it was noted that other actors conformed with their political and/or economic goals. Another finding related to power was the sense of powerlessness and frustration expressed by actors on all levels, likely enabling the status quo to prevail. There was also clear frustration towards policymakers concerning the lack of policy direction and actors expressed the need for market signaling. The policymakers seemed to adhere to both disruptive innovations and the existing regime, causing uncertainty in policy decisions. The empirics also showed that the standardization discussions have little focus on competition between standards at this point of the transition. The debate seemed to rather be shaped by the conflict between advocates and opponents of standardization, where the opponents argued against standardization due to fear of prematurely mandating a single standard. Advocates dominated over opponents at this point of the transition and the communication standard, ISO 15118 seemed to have significant industry support. Automotive manufacturers were found to be the most vocal stakeholder group against standardization. Furthermore, the results highlighted the functions and features of standards commonly mentioned in the V2G standardization discussions, where compatibility, market signaling, and future proof features belonged to the most frequently mentioned. / Elektrifieringen av transportsektorn spelar en central roll för omställningen till ett hållbart energisystem eftersom elbilar bidrar till minskade utsläpp av koldioxid. Bidirektionella laddningsmöjligheter (V2G) kan möjliggöra omställningen ytterligare genom att stötta svaga elnät på lokal nivå samtidigt som funktionen kan minska kostnaderna för att äga en elbil. Fundamentala omställningar krävs för att lösa de hållbarhetsutmaningar som flera industrier står inför men på grund av komplexiteten i dessa system kan varken privat eller offentlig sektor driva denna förändring på egen hand. Omställningsprocessen är en politisk process där standardisering kan spela en viktig roll eftersom de kan indikera vilken riktning omställningen rör sig mot. Den här uppsatsen undersöker därför standardiseringens roll i hållbarhetsomställningar. Syftet var att öka förståelsen av olika aktörers ståndpunkter i standardiseringsprocessen av kommunikationen mellan en elbil och dess laddstation. För att undersöka detta ämne granskades även maktförhållanden som genomsyrar en standardiseringsprocess. Detta gjordes genom kvalitativ kodning av två transkriberade diskussioner om standardisering från California Energy Commission vilka totalt uppgick till 667 sidor. Utöver detta hölls 13 intervjuer som komplement. Resultatet visade att makt utövades av aktörer på samtliga nivåer i systemet. Ett ömsesidigt beroende kunde identifieras mellan aktörerna. Detta antogs vara framträdande på grund av de beroendeförhållanden som uppstår sig då samtliga aktörer krävs för att ett V2G-system ska fungera. Vidare observerades att maktutövande som förstärker och reproducerar existerande strukturer och institutioner uttrycktes av många aktörer i V2G-ekosystemet. En annan observation var att biltillverkare verkar ha en stark position i V2G-ekosystemet och det noterades att andra aktörer anpassade sig efter deras politiska och/eller ekonomiska mål. Ett ytterligare resultat var att det fanns en känsla av maktlöshet och frustration på alla nivåer i systemet vilket bidrog till upplevelsen av status quo. Det fanns en tydlig frustration speciellt mot beslutsfattare vilken grundade sig i bristen på tydliga riktlinjer. Beslutsfattare verkade anpassa sig såväl mot disruptiv innovation som till den existerande regimen vilket orsakade passivitet och osäkerhet vid beslutsfattande. Eftersom ramverket Multi-Level Power-in-Transition som användes för analysen inte tar hänsyn till att beslutsfattare kan svara både mot dominanta och mer radikala makrotrender, modifierades ramverket något innan det appliceras på empirin. Vidare visade analysen att det inte pågår någon konkurrens mellan standarder i denna fas av omställningen, däremot identifierades en konflikt mellan förespråkare och motståndare till standardisering där motståndarna var oroliga över att det var för tidigt att ge mandat åt en enskild standard. Förespråkare dominerade över motståndare i denna fas av omställningen och kommunikationstandarden ISO 15118 verkade ha betydande stöd från industrin. Biltillverkare befanns vara de aktörer som till största grad motsatte sig standardisering. Resultaten gav ytterligare en inblick i de egenskaper hos standarder som vanligtvis nämndes i diskussioner om kommunikationsstandarder. Några av de egenskaper som regelbundet belystes som viktiga var kompatibilitet och att den bör vara framtidssäker. En ytterligare viktig funktion med standardisering ansågs vara att ge tydliga signaler till marknaden.

Overall my dissertation work tries to capture a holistic view of the various complex interactions that occur in technology development, implementation, adoption and diffusion, in the context of three industries by examining issues that arise due to regulation of technology. Essay 1 focuses on the social media industry, which is in the early stage of the industrial life cycle, and is the foci of government attention for its ill effect on society. Results from the study (N= 647 employed adults in the US) supported hypotheses related to the antecedents and outcomes of platform utilization in the context of the three regulation dimensions. Essay 2 focuses on the automotive industry, which is in the growth stage of the industrial life cycle. Here the focus is on electric vehicles (EV) transitioning from the niches to the main market. Results from the longitudinal study (N = 429) support the moderating role of political activism on innovation capability of manufacturers and presence of ancillary services in the diffusion of different types of electric vehicles in the US market. Essay 3 focuses on the US healthcare industry, reflecting mature stage of industrial life cycle, yet also characterized with high cost and fragmentation of service. The results supported a causal relationship and further indicate that the relationship between resources and capabilities is quadratic when evaluated in presence of regulatory challenges. In conclusion, results of three essays indicate that the effect of regulatory forces on an industry are complex and affected by multi-level interactions. Hence, taking a holistic view in understanding the impact of regulation on the utilization, implementation and eventual diffusion of technology is essential. Additionally, insights are gained by considering these impacts within the nuances of industry life cycle, evolving technology and differing regulations.

Although there are many studies focusing on the environmental impacts of alternative vehicle options, social and economic dimensions and trade-off relationships among all of these impacts were not investigated sufficiently. Moreover, most economic analyses are limited to life cycle cost analyses and do not consider macro-level economic impacts. Therefore, this thesis aims to advance the Life Cycle Sustainability Assessment literature and electric vehicle sustainability research by presenting a novel combined application of Multi Criteria Decision Making techniques with Life Cycle Sustainability Assessment for decision analysis. With this motivation in mind, this research will construct a compromise-programming model (multi-objective optimization method) in order to calculate the optimum vehicle distribution in the U.S. passenger car fleet while considering the trade-offs between environmental, economic, and social dimensions of the sustainability. The findings of this research provide important insights for policy makers when developing strategies to estimate optimum vehicle distribution strategies based on various environmental and socio-economic priorities. For instance, compromise programming results can present practical policy conclusions for different states which might have different priorities for environmental impact mitigation and socio-economic development. Therefore, the conceptual framework presented in this work can be applicable for different regions in U.S. and decision makers can generate balanced policy conclusions and recommendations based on their environmental, economic and social constraints. The compromise programming results provide vital guidance for policy makers when optimizing the use of alternative vehicle technologies based on different environmental and socio-economic priorities. This research also effort aims to increase awareness of the inherent benefits of Input-Output based a Life Cycle Sustainability Assessment and multi-criteria optimization.

Thesis advisor: Richard Sweeney / The main Investor-Owned Utilities in California charge electricity prices that are way above the social marginal cost of consuming electricity. This results in economic inefficiency which previous studies prove to have negative implications for inequality and to slow down the electrification of the transportation sector. This paper seeks to build on the existing knowledge by investigating how the high electricity prices affect low and high income house-holds’ electric vehicle adoption differently in California, and it aims to quantify the extent of such difference. The results show that EV adoption among low income households would be considerably higher under efficient retail pricing, and that low income households are more negatively affected than their high income counterparts. However, the results relative to high income households specifically are inconclusive, and therefore the extent to which the two income groups are affected differently cannot be determined. Further research should tackle this issue by including additional variables such as income by year and EV quality, as well as more granular gasoline price data. / Thesis (BA) — Boston College, 2023. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Economics.

[pt] A mobilidade urbana possui significativa interação com o meio ambiente, seja através dos recursos extraídos para produção e abastecimento de frotas automotivas ou da poluição promovida pela circulação e descarte de resíduos. Sendo do conhecimento geral que os principais combustíveis utilizados atualmente são oriundos de fontes naturais finitas e de alto impacto ambiental, faz-se necessário a avaliação de outras alternativas de propulsão dos meios de transporte. Dentro dessas condições os veículos elétricos e os veículos movidos à etanol apresentam-se como opções consistentes sob o aspecto sustentável. A abordagem desenvolvida contempla as interações entre as matrizes energéticas e elétricas, as emissões de CO2 dos diferentes tipos de propulsão, tendo em vista o comportamento de cada um desses fatores nos seguintes países: Estados Unidos, Alemanha, China, Japão, Índia e em especial o Brasil. Dessa forma, objetiva-se determinar o tipo de transporte individual com menor grau de emissões de CO2. / [en] The urban mobility has a significant interaction with the environment, it can be through resources extraction to manufacturing and to fuel automobile fleets or by pollution caused by its circulation and the waste disposal. Being common knowledge that the main fuel used nowadays are made of finite natural resources and its environmental impact, it is necessary to evaluate other alternatives to the propulsion of transportation facilities. Regarding these conditions the electrical vehicle and the ethanol powered vehicles presented themselves as consistent options from a sustainable perspective. The approach developed contemplate the interactions between the energetic and electric matrix, the CO2 emissions and the different kind of propulsion, taking care about the behavior of each factor in the following countries: USA, Germany, China, Japan, India and in special, Brazil. Therefore, is aimed to define which kind of transportation has the lower amount of CO2 released in the environment.

The automotive sector finds itself undergoing a significant and substantial transformation, propelled by the pronounced proliferation of electric vehicles (EVs) and autonomous driving technologies. As the industry proactively adapts to embrace this, an increasingly pressing demand becomes evident for higher performance, reliability, sustainability, and speed. Semiconductor packages emerge as primary catalysts within this ongoing revolution, positioned squarely at the forefront to assume a critical and indispensable function in facilitating the realization of these fundamental objectives. Commercial vehicle manufacturers are taking steps to respond to these demands for sustainability and speed, the driving force in facilitating this being the shift from Si IGBTs to SiC MOSFETs. Silicon Carbide is an increasingly popular choice in inverter module fabrication for electric vehicle applications owing to its inherent characteristics such as reduced on resistance, higher blocking voltage, and higher temperature stability that enable high power density, increased efficiency, and speeds. This work focuses on developing and fabricating a high-density 1.7 kV, 300 A SiC MOSFET half-bridge power module tailored for a 280-320 kW, 2-level inverter configuration. Co-designed with the busbar and gate driver, the custom power module stresses efficient heat dissipation, minimized parasitic inductance, and a compact footprint. Key target parameters to achieve optimal performance include a Rdson below 20 mΩ, Rthjc under 0.2 K/W and a switching time below 20 ns. The proposed module features a double-sided cooling sandwiched structure, an integrated thermistor for health and degradation monitoring, and incorporates three Wolfspeed 3rd generation 1.7 kV, 18 mΩ devices per switch position. The simulated power loop inductance is 14.5 nH, the simulated parasitic resistance is 0.265 m, and the simulated junction-to-case thermal resistance is 0.12182 ℃/W. To keep the die temperature below 150 ℃, a cooling coefficient of 5500 W/m2 is necessary. / Master of Science / The automotive sector is in the midst of a major transformation, propelled by the noticeable spread of electric vehicles (EVs) and autonomous driving technologies. As the industry actively evolves to accommodate this, an increasingly pressing demand becomes apparent for higher performance, reliability, sustainability, and speed. Semiconductor packages are at the forefront of this transformation, playing a crucial role in achieving these goals. Commercial vehicle makers are taking steps to respond to these demands for sustainability and speed, the driving force for this being the shift from Si IGBTs to SiC MOSFETs. Silicon Carbide is an increasingly popular choice in inverter module fabrication for electric vehicle applications owing to its inherent characteristics such as reduced resistance, higher blocking voltage, and higher temperature stability that enable high power density, increased efficiency, and speeds. This study focuses on creating a compact and efficient power module for commercial electric vehicle applications. The designed module is capable of handling high power levels while remaining compact, thus prioritizing power density. This is carefully designed to ensure it cools down effectively, minimizes unnecessary energy losses, and has a small footprint. Certain key features, such as its commutation speed, current carrying capacity, and thermal and mechanical limitations, were also studied. A temperature sensor was incorporated to monitor its health and performance over time. Simulations were performed to validate that this module performs well in terms of its resistances in the electrical conduction path and the oath of heat dissipation.

To ensure that e-cargo bicycles and other light electric vehicles are technically safe and used safely, an Approval Framework for Light Electric Vehicles (LEV framework) is being developed in The Netherlands. The LEV Framework also governs the place on the road of LEVs. Sessions with road authorities in the preparation of the LEV framework in 2020 showed that some road authorities were concerned about heavy e-cargo bicycles on bicycle paths because of their size and the mass difference with cyclists. For this reason, it was investigated what the most suitable traffic rules are for the place on the road of heavy e-cargo bicycles for transporting goods or children with a maximum construction speed of 25 km/h: the cycle path, the carriageway or, depending on the traffic situation, a tailor-made solution in between.