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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Identification of Optimal Fast Charging Control based on Battery State of Health

Salyer, Zachary M. 01 October 2020 (has links)
No description available.
12

The application of financial analysis in business modelling : A case study of a public fast-charging station for electric heavy-duty vehicles in Sweden

Arfaoui, Ghaith, Leffler, Thomas January 2023 (has links)
Background: Climate changes and global warming call for behaviour changes from mankind and for new business models to introduce sustainable innovations. Financial analysis plays an important role in guiding the choice of these business models. However, assumptions and uncertainties pose challenges to the use of financial analysis in business modelling. Purpose: The purpose of this study is to develop a proactive systematic approach of financial analysis in business modelling. Accounting for the important role of assumptions and uncertainty factors, the approach should guide the choices of capital structure, revenue model, and strategic partnerships in the business model. Methodology: The developed approach combines the use of different methods to assess different business models for a public fast-charging stations for electric heavy-duty vehicles in Sweden. The used techniques are DCF analysis, What-If analysis, Tornado diagram, Monte-Carlo simulation, and multiple linear regression analysis. Results and analysis: Applied to the case of a public fast-charging station for electric heavy-duty vehicles, the approach leads to the identification of potential viable business models. Under the condition of using financial leverage through debt, additional revenue sources such as per-charge event user fee and advertising as well as partnership with the public sector in the form of grants, it is possible to achieve a viable business model. Conclusions: A systematic proactive approach of the use of financial analysis in business modelling was successfully developed and applied to the case of fast-charging stations for electric heavy-duty vehicles. The identified viable business models rely on financial leverage through debt, additional revenue sources and partnership with the public sector in the form of grants. Recommendations for future research: Simulations with more input parameters as well as combinations with observational studies of existing business models can be further investigated.
13

Electric Vehicles & Fuel Retailers : Challenges with the Provision of Fast Charging in Swedish Fuel Stations / Elektriska fordon & drivmedelsbolag : Utmaningar med tillhandhållandet av snabbladdning på svenska drivmedelsstationer

Thorsell, Gustav January 2020 (has links)
Battery-Electric Vehicles (BEVs) are gaining increasing momentum and their adoption is projected to continue at a rapid pace. In contrast to the predominate vehicle type, Internal-Combustion Engine Vehicles (ICEVs), the BEVs rely on electricity rather than conventional fuels for propulsion. For the fuel retailers, the actors managing fuel stations and supply fuel to vehicle users, the shift towards BEVs may impose a demand decline for their core product. One way of mitigating the effects of this transition for fuel retailers, has been attributed to the provision of charging for electric vehicles in fuel stations, something that is offered to a limited extent by a few fuel retailers in Sweden today. The purpose of this study has been to explore the main challenges associated with the provision of fast charging in Swedish fuel stations.  Anchored in a study of the four largest fuel retailers in Sweden, the findings suggest that the provision of fast charging is subject to financial challenges in terms of long investments horizons, with the associated investment risk being negatively influenced by uncertainties of technology development, future price levels for fast charging and future utilization rates of the chargers. Furthermore, with the lack of direct financial incentives of charging sales in the short-term, other motives have been observed for the provision of fast charging, namely goodwill and traffic building. The prevalence of different types of fuel retail formats have been shown to influence the extent of which benefits can be claimed from fast charging provision, and that this is manifested in a bias towards certain formats and locations for the choice of fuel stations to provide fast charging in. Challenges have also been identified in the sense of fulfillment of necessary preconditions to facilitate a business model suitable for fast charging provision. The study concludes that the main challenges revolve around the attainment of a financially sustainable business case for fast chargers. / Elfordon blir allt mer populära och utvecklingen förväntas försätta i hög takt. I kontrast med den vanligast förekommande motortekniken för vägfordon, förbränningsmotorn, så använder elfordon just el istället för konventionella bränslen för framdrift. För drivmedelsbolagen, de aktörer som ansvarar för drivmedelstationer och tillhandhåller drivmedel till fordonsanvändare, kan en övergång mot elfordon innebära en minskad efterfrågan på deras kärnprodukt. Ett sätt att hantera konsekvenserna av en minskad efterfrågan på drivmedel, har tillskrivits tillhandahållandet av laddning för elfordon på drivmedelsstationerna, ett erbjudande som idag tillhandahålls av ett fåtal drivmedelsbolag på ett begränsat antal stationer i Sverige. Syftet med den här studien har varit att undersöka de huvudsakliga utmaningarna med tillhandhållandet av snabbladdning på drivmedelsstationer i Sverige.  Baserat på en studie av de fyra största drivmedelsbolagen i Sverige, pekar resultaten på att tillhandahållandet av snabbladdning medför stora finansiella utmaningar. Detta innefattar långa investeringshorisonter, med en investeringsrisk som påverkas negativt av osäkerheter kring teknikutveckling, framtida prisnivåer för snabbladdning och framtida användningsgrad av snabbladdare. Med en avsaknad av direkt kortsiktig finansiell vinning från försäljning av snabbladdning, så har det framgått att det finns andra motiv för tillhandahållandet av snabbladdning, det handlar då om kundflöde och goodwill. Förekomsten av olika stationsformat för drivmedelsförsäljning har visat sig påverka till vilken grad skapat värde från snabbladdningserbjudandet kan tillgodoses, och att det har påverkat val av stationsformat och plats för tillhandahållandet av snabbladdning. Ytterligare utmaningar har identifierats gällande att skapa nödvändiga förutsättningarna för att möjliggöra en affärsmodell anpassad för snabbladdning. En slutsats har dragits att de huvudsakliga utmaningarna med tillhandahållandet av snabbladdning handlar om att uppnå en finansiellt hållbar affär.
14

Testing and Thermal Management System Design of an Ultra-Fast Charging Battery Module for Electric Vehicles / Battery Module Thermal Management System Design

Zhao, Ziyu January 2021 (has links)
This thesis consists of three main objectives: fundamental and literature review of EV batteries, experimental development, and validation of two liquid cooling battery modules, thermal modeling and comparison of the inter-cell cooling battery module. / The traditional vehicles with internal combustion engine have resulted in severe environmental pollution, which motivates the development of electric vehicles and hybrid electric vehicles. Due to a low energy density and long refueling time of the battery pack, it is still hard for electric vehicles and hybrid electric vehicles to be widely accepted by the consumers. As the batteries with a better ultra-fast charging capability are massively produced, the range anxiety issue is somewhat alleviated. During a charging with large current magnitude, the battery generally has a great amount of heat generation and evident temperature rise. Therefore, a thermal management system is necessary to effectively dissipate the battery loss and minimize the degradation mechanisms caused by extreme temperature. The motivation of this thesis is to study the discipline of the battery thermal management system as an application for electric vehicles. The design methodologies are presented in both experiment test and numerical simulation. For the comparative study between active liquid cooling methods for a lithium-ion battery module using experimental techniques, two battery modules with three Kokam Nickel Manganese Cobalt battery cells connected in parallel are developed. One has liquid coolant flowing along the edge of the model, and another with liquid coolant flowing between the cells. Several characterization tests, including thermal resistance tests, fast charging tests up to 5C, and drive cycle tests are designed and performed on the battery module. The inter-cell cooling module has a lower peak temperature rise and faster thermal response compared to the edge cooling module, i.e., 4.1⁰C peak temperature rise under 5C charging for inter-cell cooling method and 14.2⁰C for edge cooling method. The thermal models built in ANSYS represent the numerical simulation of the inter-cell cooling module as a comparison with the experiment. A cell loss model is developed to calculate the battery heat generation rate under ultra-fast charging tests and a road trip test, which are further adopted as the inputs to the thermal models. The simulation of the 5C ultra-fast charging test gives the peak temperature rise just 0.47⁰C lower than the experimental measurement, it indicates that the FEA thermal models can provide an accurate temperature prediction of the battery module. / Thesis / Master of Applied Science (MASc) / With a demanding market of electric vehicles, battery technologies have grown rapidly in recent years. Among all the battery research topics, the development of ultra-fast charging, that can fully charge the battery pack within 15 minutes, is the most promising direction to address the range anxiety and improve the social acceptance of electric vehicles. Nevertheless, the application of ultra-fast charging has many challenges. In particular, an efficient thermal management system is significant to guarantee the safety and prolong the service life of the battery pack. This thesis contributes to study the fundamentals of the battery field, and design liquid cooling systems to observe the thermal behavior of a battery prototype module under fast charging and general use. FEA thermal modeling of the battery module is developed to provide a guide for further test validation.
15

Designing an EV Charger & Battery Storage Unit : Adapted to Scandinavian Residential Environments

Hörnström, Linnea, Nilsson, Fredrik January 2023 (has links)
The global automotive industry is currently experiencing a shift as the sector converts from fossil fuels to electric vehicles (EVs). However, the existing infrastructure for EV charging is facing difficulties in meeting the growingdemand in terms of accessibility and technical performance. In response, companies such as Zpark EnergySystems are actively engaged in the development of chargers to cater to the needs of the next generationchargers. As part of their efforts, Zpark has introduced a new product segment specifically tailored to thegrowing market demand, by creating a fast charger for the residential market. This thesis aims to create anexterior design for the charger and battery storage unit (BSU) suited to Scandinavian residential environments.The project has been divided into three main focus areas. The first area concerns design where primarily formtheory, material science and ergonomics have been researched. To validate the theory which established thedesign elements and features of the charger and BSU, extensive user testing was performed. The second areaconcerns adaptation in terms of how the product design will suit the intended home market. Scandinavian-architecture, -design, -colours and -climate has been studied for this area. The final focus area concerns theinteraction between users and mainly the charger. Research has been conducted to explore the integration ofuser interactive features into the design. The usability of these features has also been thoroughly examinedthrough user testing. Which has been combined with theories related to colour, human-machine interaction, andform theory in order to create a user-friendly interaction experience.The project approach has been divided into the following steps; exploration, ideation, evaluation andimplementation. For the explore phase background theory to the project was researched and methods such asbenchmarking, white space analysis, customer journey, placement analysis, and user research were conductedto gain an understanding of the market and the current pain points. For the ideation phase the goal was togenerate a large number of design concepts for both the charger and BSU. This was achieved through variousinternal ideatios methods within the team as well as external methods at workshops. To narrow down betweenthe design concepts an evaluation matrix was used which resulted in a final concept that was brought forward tothe next project phase, namely the evaluation. The evaluation phase concerned testing the final conceptsthough user testing and making technical specifications according to theory. At the end of this stage a finaldesign was achieved where all details were specified and loose ends tied together. The last phase concerningimplementation was then performed in correlation with the specified design through producing digital 3Dvisualisations and creating an animation of the final designs.The project resulted in an exterior design for the charger as well as the BSU which fulfils the aims of the projectscope. The design incorporates the features found to be necessary in the background research. Further auser-friendly design was established through various user tests investigating the integrated features and revisingthem according to the user test results. Adaptation to the home market is achieved through customisablecolours and modularity of the BSU. The design incorporates the characteristics of Scandinavian design boththrough its form elements and by the use of materials which makes the charger and BSU suit a Scandinavianresidential environment in a visually cohesive and aesthetically pleasing way. / Fordonsindustrin genomgår en omfattande förändring då branschen konverterar från fossila bränslen tillelektriska fordon (EF). Branschen står inför utmaningar de kommande åren då den befintliga infrastrukturen förelbilsladdning har svårigheter att möta den ökande efterfrågan när det gäller tillgänglighet och tekniskprestanda. Därav är företag som Zpark Energy Systems aktiva i utvecklingen av innovativa laddare för atttillgodose dessa behov hos nästa generations laddare. I linje med deras satsningar har Zpark introducerat en nyproduktkategori specifikt anpassad till den växande marknadsefterfrågan genom att skapa en snabbladdaresom är skräddarsydd för bostadsmarknaden. Detta examensarbete syftar till att skapa en exteriör design försnabbladdaren samt tillhörande batterilagringsenhet (BLE) anpassad till Skandinavisk bostadsmiljö.Projektet har delats upp i fyra huvudsakliga fokusområden. Det första området centrerar kring design där främstformteori, materialvetenskap och ergonomi har studerats. För att validera teorin som designelement ochfunktioner för laddaren och BLE har baserats på så utfördes användartester. Det andra fokusområdet i projektetavser anpassning i form av hur produktens design ska anpassas till den avsedda bostadsmiljön. Teori gällandeskandinavisk arkitektur, design, färger och klimat har studerats för att skapa en akademisk grund för dettaområde. Det sista fokusområdet för projektet rör interaktionen mellan användare och främst laddaren.Användartester har genomförts för att utforska integrationen av interaktiva funktioner i designen och dessanvändbarhet. Detta har kombinerats med teorier relaterade till färgsättning, människa-maskin-interaktion ochformteori för att skapa en användarvänlig upplevelse under laddningsprocessen.Projektets tillvägagångssätt är uppdelat i tre huvudmoment: utforskning, idégenerering, utvärdering ochimplementering. Under utforskningsfasen undersöktes bakgrundsteori för projektet och metoder sombenchmarking, white space analysis, customer journey, placeringsanalys och användarstudier användes för attfå en förståelse för marknaden och befintliga utmaningar. Under idégenereringsfasen var målet att generera ettstort antal designkoncept för både laddare och BLE. Detta uppnåddes genom olika interna och externaidégenereringsmetoder och workshops. För att välja bland designkoncepten användes en utvärderingsmatrissom resulterade i ett slutgiltigt koncept vilket sedan togs vidare till nästa projektfas. Utvärderingsfaseninnefattade utvärdering av det valda design konceptet genom användartester och tekniska specifikationer enligtteorin. Vid slutet av denna fas uppnåddes en slutlig design där alla detaljer specificerades och lösa ändar knötsihop. Den sista fasen rör implementering och utfördes i enlighet med den specificerade designen genom attproducera digitala 3D-visualiseringar och skapa en animering av de slutgiltiga designerna.Projektet resulterade i en exteriör design för laddaren och BLE:n som uppfyller projektets mål: Designeninkluderar de funktioner som identifierats som nödvändiga i bakgrundsundersökningen. När det gällerfunktionaliteten skapades en användarvänlig design genom olika användartester som utvärderade deintegrerade funktionerna vilka reviderades utifrån resultatet i testerna. Anpassning till hemmamarknaden uppnåsgenom anpassningsbara färger och modularitet för BLE. Designen innehåller kännetecknen för skandinaviskdesign både genom sina formelement och genom användningen av material vilket gör att laddare och BSUpassar i en skandinavisk bostadsmiljö på ett estetiskt tilltalande sätt med hög funktionalitet.
16

DUAL ACTIVE BRIDGE (DAB) DC/DC CONVERTER WITH WIDE OUTPUT VOLTAGE RANGE FOR EV FAST CHARGING APPLICATIONS

Zayed, Omar January 2024 (has links)
Faster charging and availability of charging infrastructure are the two main challenges facing an accelerated transition to sustainable electri ed transportation. Both challenges can be solved by developing modular charging systems that are future proof all while having low running and installation costs. As such, this thesis focuses on developing modular and e cient DC/DC charging solutions with a wide charging voltage range capability to meet the needs of existing and next generation plug-in electric vehicles. The thesis starts with describing its motivation and gives an overview on the impact of charging technologies on the electri fication movement. Then, specifi c objectives and research contributions are laid out to narrow the focus of the reader. A review on existing charging systems, standards, architecture and features is presented. Existing isolated and on-isolated power converter topologies for DC-chargers are analyzed and research gaps in power converters with a wide charging voltage range are highlighted. A new single stage DC/DC converter topology and operation scheme is proposed to extend the charging voltage range. Modeling and analysis of the proposed solution was used to select the transition point between different operating modes. Impedance tolerance and pulse distortion was modeled to analyze the passive current sharing error at light and full load operation. The combination of the proposed topology and unique operating scheme reduced the voltage and current stress per device allowing the use of lower kVA rated devices leading to higher cost savings compared to other solutions. An experimental setup has been developed which showed the excellent performance of the proposed topology. The design and optimization strategy for the proposed dual-secondary dual-active bridge (DAB) converter topology is presented. A converter loss model is developed to take in to account: magnetic, switching, and conduction loss. Then, the design process and quantization scheme to quantize charging pro les into discrete energy points is explained, which entails parametric optimization using a genetic algorithm (GA) to minimize energy loss across widely varying charging pro les based on actual charging data. Comprehensive experimental testing was carried out to validate the proposed design strategy and excellent performance was achieved over an extended operating range. After the review of power magnetics used in isolated chargers, high parasitic capacitance in planar transformers was identi ed as an obstacle in the way of development of chargers, especially in charging applications that demand high switching frequencies or extended low power operation. Therefore, a novel planar transformer structure was proposed with ultra-low winding capacitance. The proposed co-planar transformer was compared to three other planar types to highlight the differences and bene fits. Four different prototypes of planar transformers were built with the same target speci fications, to compare the proposed structure against previous solutions. Impedance testing of the planar prototypes was carried to measure the winding stray capacitance and frequency response. Experimental power testing using a DAB converter setup showed excellent results in reducing voltage overshoot, high frequency oscillations, and power losses. Finally, a 30-kW dual-secondary DAB charging module was designed, implemented, and tested. The purpose of this work is to bridge the engineering gap between a proof of concept and a higher Technology Readiness Level (TRL) mature charging module, focusing more on regulatory standards and control system development. Experimental validation of the liquid cooled module showed excellent performance characteristics. / Thesis / Doctor of Philosophy (PhD)
17

Design of a LLC Resonant Converter Module with Wide Output Voltage Range for EV Fast Charging Applications

Elezab, Ahmed January 2023 (has links)
The move toward electric vehicles (EVs) has a significant impact to reduce greenhouse gas (GHG) emissions and make transportation more eco-friendly. Fast-charging stations play a crucial role in this transition, making EVs more convenient for adoption specifically when driving in long distance. However, the challenge is to create a fast-charging system that can work with the different types of EVs and their varying power needs while still being efficient and effective. In this context, this thesis embarks on this journey by introducing an innovative solution for efficient universal fast charging, spanning both low voltage and high voltage battery systems. A novel, configurable dual secondary resonant converter is proposed, which empowers the charging module to extend its output range without imposing additional demands on the resonant tank components. This solution addresses the pressing need for a wide output voltage range in fast-charging standard in the growing EV landscape. To ensure optimal performance across a broad voltage and power range, the thesis employs an analytical model for LLC resonant converters to optimize the resonant components. This strategic component selection aims to achieve the desired output voltage and power range while minimizing conduction losses. The proposed topology and design methodology are rigorously validated through the development of a 10 kW prototype. Furthermore, the study introduces a two degrees of freedom (2DoF) control scheme for the proposed LLC resonant converter with the configurable dual secondary LLC converter topology. An analytical model is formulated to guide the selection of control parameters, ensuring coverage of the desired output voltage and power range without compromising system efficiency. The steady-state analytical model is utilized for determining optimized control parameters at each operating point within the converter's output range. To enhance the charging module's power density and efficiency, a high-frequency litz-wire transformer design methodology is introduced. The transformer's core size is optimized to achieve high power density and efficiency, while the winding configuration is chosen to minimize conduction losses. Finite Element Analysis (FEA) simulations validate transformer losses and operating temperatures. The culmination of this research is the development of a 30 kW charging module prototype. This prototype features an LLC resonant converter with a configurable dual secondary and two degrees of freedom control for output voltage control. The component ratings, estimated losses, and power board design are carefully considered to create a compact and efficient charging module. Experimental testing across a universal output voltage and power range con rms the effectiveness of the proposed solution. In summary, this thesis presents a comprehensive approach to design of a module for EV fast charging application addressing voltage range, efficiency, and component optimization, resulting in the successful development of a high-performance charging module prototype. / Thesis / Doctor of Engineering (DEng)
18

MECHANISTIC ROLE OF THERMAL EFFECTS ON LITHIUM PLATING

Conner Fear (13171236) 28 July 2022 (has links)
<p> In the pursuit to enable the rapid charging of lithium-ion batteries, lithium plating at the anode  poses one of the most significant challenges. Additionally, the heat generation that accompanies  high rate battery operation in conjunction with non-uniform cooling and localized heating at tabs  is known to result in thermal inhomogeneity. Such thermal anomalies in the absence of proper  thermal management can instigate accelerated degradation in the cell. This work seeks to elucidate  the link between thermal gradients and lithium plating in lithium-ion batteries using a combined  experimental and simulation-based approach. First, we experimentally characterize the lithium  plating phenomenon on graphite anodes under a wide variety of charging rates and temperatures  to gain mechanistic insights into the processes at play. An in operando detection method for the  onset of dendritic lithium plating is developed. Lithium plating regimes are identified as either  nucleate or dendritic, which exhibit vast differences in reversibility. An operando method to  quantify lithium stripping based on the rest phase voltage plateau is presented. Next, a model is  employed to provide fundamental insights to the thermo-electrochemical interactions during  charging in scenarios involving an externally imposed in-plane and inter-electrode thermal  gradient. The relative importance of in-plane vs. inter-electrode thermal gradients to charging  performance and cell degradation is necessary to inform future cell design and cooling systems for  large-format cells, which are crucial for meeting the energy requirements of applications like  electric vehicles. While in-plane thermal gradients strongly influence active material utilization,  the lithium plating severity was found to be very similar to an isothermal case at the same mean  temperature. By contrast, inter-electrode thermal gradients cause a shifting on the solid phase  potential at each electrode during charging, related to the increase or decrease in overpotential due  to local temperature variation. An experiment is then performed on a commercial multi-layer  pouch cell, in which it was found that applied thermal gradients provide a slight reduction in  lithium plating severity and degradation rate when compared to an isothermal cell at the same  mean temperature. The presence of a thermal gradient causes heterogeneous lithium plating  deposition within the cell, with colder regions experiencing higher quantities of plating and larger  thermal gradients leading to more severe heterogeneity.   </p>
19

Testing, Characterization, and Thermal Analysis of Lithium-Ion Batteries Toward Battery Pack Design for Ultra-Fast Charging

He, Melissa January 2018 (has links)
Ultra-fast charging of electric vehicles will soon be available to charge the batteries in less than 15 minutes to 80% state of charge. However, very few studies of batteries under these conditions exist. To design a battery pack with ultra-fast charging in mind, more information about batteries is needed, both electrically and thermally. In this thesis, the performance of three specific commercial lithium-ion batteries during ultra-fast charging is investigated and their thermal behaviour is simulated for use in the battery pack design process. The cells are charged at 1C to 6C current rates, or as high as 10C, and the surface temperature of each cell is measured. The loss calculated from the charging tests are used in a thermal analysis of the three batteries using finite element analysis. The batteries are modeled in a simple cooling apparatus to determine their thermal management requirements in a pack, i.e., how effectively must the heat be removed from the cells to obtain a specific temperature in a pack. Test results show that ultra-fast charging is possible with very little loss; but, it is dependent on the battery. The analysis illustrates important trade-offs between the battery type, charge rate, and the thermal management system. This thesis presents a holistic view to the study of the batteries for eventual use in the design of a battery pack. The thermal performance of the batteries is equally important as their electrical (charge) performance. It also attempts to justify the observed behaviour of the batteries by their underlying chemical behaviour. The work here can be used as a jumping-off point for further work on the ultra-fast charging of batteries or the design of a battery pack. / Thesis / Master of Applied Science (MASc) / Ultra-fast charging of electric vehicles, i.e., fully charging the vehicle in less than 15 minutes, will soon be more available. However, literature on the ultra-fast charging of the batteries used in these vehicles is limited. It is not widely known whether the batteries can effectively achieve ultra-fast charging or how the batteries behave under these conditions. Charging batteries this fast means that the battery cells will heat up. The temperature of the cell greatly impacts its longevity and safety. The thesis attempts to address these questions by studying three commercial lithium-ion batteries, selected for specific characteristics, that show potential for ultra-fast charging. The batteries are charged at different rates to ultra-fast charging levels and the charge performance at each rate is determined. The temperature of the batteries is simulated with different cooling systems to determine how effectively must heat be removed from the batteries to maintain the cells at a specific temperature.
20

Simulation and Experiments to Understand the Manufacturing Process, Microstructure and Transport Properties of Porous Electrodes

Forouzan, Mohammad Mehdi 01 April 2018 (has links)
Battery technology is a great candidate for energy storage applications. The need for high-performance and cost-effective batteries has motivated researchers to put much effort into improving battery performance. In this work, we attempt to understand the elements that affect the microstructure and performance of two battery systems. The first part of this work focuses on the investigation of transport and structural properties of porous electrodes in an alkaline electrolyte. A DC polarization method was deployed for tortuosity measurements. An apparatus was designed to flow specified current through and measure the voltage drop over the porous electrodes. Using a modified Ohm's law, effective diffusion coefficient and associated tortuosity were determined. Multiple compositions (different types and amounts of conductive additives) were tested to understand the effects of composition on the transport properties. As a validation and to further understand the tests, a model was developed and used for data analysis. The second part of this dissertation describes simulations of the manufacturing process of a Li-ion electrode. LAMMPS, a particle simulator, was used for this meso-scale particle-based simulation. The interactions between particles were understood by model-experiment comparisons of the macroscopic properties such as viscosity of the slurry and elasticity of the dried film. The microstructure created by this simulation was consistent with the one we observed in SEM/ FIB images. Although the emphasis was the drying process in this part, some preliminary coating and calendering simulations are presented. Finally, the effects of electrode heterogeneity were investigated by a Newman-type model and tomographic images. An electronic conductivity map was initially generated over a Li-ion cathode. Then SEM/FIB images of specified high, middle, and low conductivity regions were taken to confirm heterogeneity. For modeling purposes, three regions of high, middle, and low ionic resistance were considered connected in parallel, representing the real electrode heterogeneity. Multiple cases of heterogeneities such as non-uniform ionic resistance and active material loading at low, middle, and high charge-discharge rates were studied. The results show that higher rates increase non-uniformities of dependent properties such as temperature, current density, positive and negative electrodes states of charge, and charge and discharge capacities especially in charging cases.

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