Energy storage provides sustainability when coupled with renewable but intermittent energy sources such as solar, wave and wind power, and electrochemical supercapacitors represent a new storage technology with high power and energy density. For inclusion in supercapacitors, transition metal oxide and sulfide electrodes such as RuO2, IrO2, TiS2, and MoS2 exhibit rapid faradaic electron–transfer reactions combined with low resistance. The pseudocapacitance of RuO2 is about 720 F/g, and is 100 times greater than double-layer capacitance of activated carbon electrodes. Due to the two-dimensional layered structure of MoS2, it has proven to be an excellent electrode material for electrochemical supercapacitors. Cathodic electrodeposition of MoS2 onto glassy carbon electrodes is obtained from electrolytes containing (NH4)2MoS4 and KCl. Annealing the as-deposited Mo sulfide deposit improves the capacitance by a factor of 40x, with a maximum value of 360 F/g for 50 nm thick MoS2 films. The effects of different annealing conditions were investigated by XRD, AFM and charge storage measurements. The specific capacitance measured by cyclic voltammetry is highest for MoS2 thin films annealed at 500°C for 3h and much lower for films annealed at 700°C for 1 h. Inclusion of copper as a dopant element into electrodeposited MoS2 thin films for reducing iR drop during film charge/discharge is also studied. Thin films of Cu-doped MoS2 are deposited from aqueous electrolytes containing SCN-, which acts as a complexing agent to shift the cathodic Cu deposition potential, which is much more anodic than that of MoS2. Annealed, Cu-doped MoS2 films exhibit enhanced charge storage capability about 5x higher than undoped MoS2 films. Coal combustion is currently the largest single anthropogenic source of CO2 emissions, and due to the growing concerns about climate change, several new technologies have been developed to mitigate the problem, including oxyfuel coal combustion, which makes CO2 sequestration easier. One complication of oxyfuel coal combustion is that corrosion problems can be exacerbated due to flue gas recycling, which is employed to dilute the pure O2 feed and reduce the flame temperature. Refractory metal diffusion coatings of Ti and Zr atop P91 steel were created and tested for their ability to prevent corrosion in an oxidizing atmosphere at elevated temperature. Using pack cementation, diffusion coatings of thickness approximately 12 and 20 µm are obtained for Ti and Zr, respectively. The effects of heating to 950°C for 24 hr in 5% O2 in He are studied in situ by thermogravimetric analyses (TGA), and ex situ by SEM analyses and depth profiling by EDX. For Ti-coated, Zr-coated and uncoated P91 samples, extended heating in an oxidizing environment causes relatively thick oxide growth, but extensive oxygen penetration greater than 2.7 mm below the sample surface, and eventual oxide exfoliation, are observed only for the uncoated P91 sample. For the Ti- and Zr-coated samples, oxygen penetrates approximately 16 and 56 µm, respectively, below the surface. In situ TGA verifies that Ti-and Zr-coated P91 samples undergo far smaller mass changes during corrosion than uncoated samples, reaching close to steady state mass after approximately four hours.

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Nobel Biocare är världsledande inom tillverkning av tandimplantat. Implantaten tillverkas av titan och måste efter tillverkning sterilförpackas för att skyddas från oönskade partiklar. Förpackningen som används är en blisterförpackning som limmas ihop i en blistermaskin. För att kontrollera att förpackningen uppfyller de krav som ställs på medicinsk tillverkning kontrolleras tätheten med hjälp av tre olika kvalitetskontroller. Dessa kontroller är tidskrävande och innebär onödig kassation då de blisterark som kontrolleras måste kasseras.  Syftet med detta arbete var att undersöka möjligheten att automatisera de manuella kvalitetskontrollerna. Automation skulle innebära besparingar i både tid och material. Det skulle också innebära att en relativt stor golvyta i förpackningsrummet skulle kunna frigöras, ytan rymmer i dagsläget två bord med diverse hjälpmedel som behövs för att utföra de manuella kvalitetskontrollerna. I samråd med företaget riktades arbetet in på att undersöka om automatiseringen skulle kunna göras med hjälp av visionsystem.  Eftersom blisterförpackningarna till större delen består av plast ansågs belysningen för visionsystemet vara den största utmaningen. Tester genomfördes på företaget Prevas i Karlstad där olika typer av ljussättning provades tillsammans med en visionkamera. Testerna visar att limmet på blisterförpackningarna är fluorescerande och blev tydligt i UV-ljus. Detta innebär att UV-ljus skulle kunna användas vid en automatisering med visionsystem.   Slutligen kontaktades olika företag, bland annat Karlskoga Automation och Neurolearn. Företagskontakt var en viktig del i arbetet då samtliga företag som kontaktades arbetar med automationslösningar. De företag som projektet presenterades för ansåg att det är möjligt att ersätta de manuella kvalitetskontrollerna med ett visionsystem och de hade möjlighet att leverera en sådan lösning till Nobel Biocare. / Nobel Biocare is a world leading company in the manufacture of dental implants. The implants are made of titanium and must be packed sterile to protect the implants from unwanted particles. The package used is a blister pack that is glued together in a blister machine. Three different quality controls are done manually to ensure that the packaging meets the requirements for medical manufacture. The quality controls are time-consuming and involve unnecessary disposal.  The purpose of this thesis was to investigate the possibility of this process being automated. Automation would mean that savings can be made for time and materials. It would also mean that a relatively large floorspace could be freed up in the packing room. The surface currently holds two tables that contains various equipment used to perform the manual quality controls. In consultation with the company the investigation was focused on using a vision system for automation. Since the blister packs mostly consists of plastic the lighting for the vision system was considered to be the biggest challenge. Lighting tests were performed at Prevas in Karlstad where a vision camera and different types of lights were used. The result shows that the blister packs contain fluorescent glue that became visible in UV light. This means that UV light can be used to automate the process with a vision system.  Finally, various companies were contacted, including Karlskoga Automation and Neurolearn. All companies that were contacted work with creating automation solutions and that made the contact important for this thesis. The companies to which the project was presented, they all considered it to be achievable. They also could deliver such a solution for Nobel Biocare.

The transient thermal response of a 15-cell, 48 volt, lithium-ion battery pack for an unmanned ground vehicle was simulated with ANSYS Fluent. Heat generation rates and specific heat capacity of a single cell were experimentally measured and used as input to the thermal model. A heat generation load was applied to each battery and natural convection film boundary conditions were applied to the exterior of the enclosure. The buoyancy-driven natural convection inside the enclosure was modeled along with the radiation heat transfer between internal components. The maximum temperature of the batteries reached 65.6 °C after 630 seconds of usage at a simulated peak power draw of 3,600 watts or roughly 85 amps. This exceeds the manufacturer's maximum recommended operating temperature of 60 °C. The pack was redesigned to incorporate a passive thermal management system consisting of a composite expanded graphite matrix infiltrated with a phase-changing paraffin wax. The redesigned battery pack was similarly modeled, showing a decrease in the maximum temperature to 50.3 °C after 630 seconds at the same power draw. The proposed passive thermal management system kept the batteries within their recommended operating temperature range.

Sustainable design is often practiced and assessed through the consideration of three essential areas: economic sustainability, environmental sustainability, and social sustainability. For even the simplest of products, the complexities of these three areas and their trade-offs cause decision making transparency to be lost in most practical situations. Additionally, the models and tools available to consider social sustainability are severely underdeveloped. This thesis is separated into three parts: 1) a design tool to consider all three aspects of sustainability simultaneously, 2) a literature survey to characterize social impact as it relates to products, and 3) interviews with engineering professionals regarding how social impact is currently considered in product design in industry.The existing field of multi-objective optimization offers a natural framework to define and explore a given design space. In chapter 2 of this thesis, a method for defining a products sustainability space (defined by economic, environmental, and social sustainability objectives) is outlined and used to explore the trade-offs within the space, thus offering both the design team and the decision makers a means of better understanding the sustainability trade-offs. This chapter concludes that sustainable product development can indeed benefit from trade-off characterization using multi-objective optimization techniques “ even when using only basic models of sustainability. Interestingly, the unique characteristics of the three essential sustainable development areas lead to an alternative view of some traditional multiobjective optimization concepts, such as weak Pareto optimality. The sustainable redesign of a machine to drill boreholes for water wells is presented as a practical example for method demonstration and discussion. In these efforts it became apparent that the tools for considering social impact were lacking and needed to be further developed.While efforts have been made to identify social impacts, academics, and practitioners still disagree on which phenomena should be included, and few have focused on the impacts of products specifically compared with programs, policies, or other projects. The primary contribution of chapter 3 of this thesis is to integrate scholarship from a wide array of social science and engineering disciplines that categorizes the social phenomena that are affected by products. Specifically, we identify social impacts and processes including population change, family, gender, education, stratification, employment, health and well-being, human rights, networks and communication, conflict and crime, and cultural identity/heritage. These categories are important because they can be used to inform academics and practitioners alike who are interested in creating products that generate positive social benefits for users.Though academic research for identifying and considering the social impact of products is emerging, additional insights can be gained from engineers who design products every day. Chapter 4 explores current practices in industry used by design engineers to consider the social impact of products. 46 individuals from 34 different companies were interviewed to discover what disconnects exist between academia and industry when considering a products social impact. These interviews were also used to discover how social impact might be considered in a design setting moving forward. This is not a study to find the state of the art, but considers the average engineering professionals work to design products in various industries. Social impact assessments (SIA) and social life cycle assessments (SLCA) are two of the most common processes discussed in the literature to evaluate social impact, both generally and in products. Interestingly, these processes did not arise in any discussion in interviews despite respondents affirming that they do consider social impact in product design. Processes used to predict social impact, rather than simply evaluate, were discussed by the respondents and tended to be developed within the company and often related to industry imposed government regulations.The combined work reported in this thesis is a significant step forward in being able to handle the unwieldy nature of social impact in product design in the larger context of sustainability. Not only do these efforts provide a basis upon which future tools can be developed, they are also immediately useful in providing a basic framework upon which to consider the full spectrum of social impact of products during design.

Med övergången till elektrifiering inom transport uppstår nya utmaningar när det gäller batterisystem som placeras i elfordon. Det finns för närvarande en möjlighet att minska riskerna med toxiciteten hos partiklar som sprutas ut med de gaser som bildas under termisk rusning i litiumjonbattericeller som är placerade i batterisystem. Syftet med denna avhandling är att identifiera potentiella material för partikelfiltrering från dessa gaser, undersöka de valda materialens prestanda i ett experiment, och föreslå material för framtida studier. Filtermaterialet är avsett att sitta vid ventilen i batteripacket. Totalt valdes 5 filter för experimenten, där 3 av dessa var mikrofiberfilter gjorda av kvarts och 2 var mikrofiberfilter av glas. Filtren klämdes mellan stålplattor med ett hål, och placerades 40 cm ovanför battericellens ventil. Battericellerna utlöstes till termisk rusning och filtren placerades i den direkta vägen för utslungade partiklar för att testa deras termiska motstånd och partikelretentionsförmåga. Filtren karaktäriserades med hjälp av vägning, svepelektronmikroskopi, samt energidispersivt röntgenspektroskopi. Efter ett första test ansågs glasfiberfiltren inte ha tillräckligt hög värmeresistens för att fortsätta testas. Kvartsmikrofiberfiltren varierade i fråga om värmeresistens, där de ibland brann upp och ibland förblev helt intakta. Detta berodde troligtvis till stor del på skillnader i termisk rusning mellan experimenten på grund av varierande uppvärmningsparametrar. Kvalitativt sett lyckades kvartsmikrofiberfiltren fånga upp partiklar, men det kan inte kvantifieras i detta experiment hur effektiva de var när det gäller partikelretention. Filtren visade potential för en enkel tillämpning i batteripacket, men ytterligare forskning bör göras för att undersöka viktiga faktorer, såsom mottryck från filtren. Dessutom finns det vissa material som kan vara intressanta att testa i framtiden, bland annat keramiska material, sintrade metallfiberfiltar och ablativa material. / With the shift towards electrification in transportation, new challenges arise with regards to battery systems placed in electric vehicles. There is an opportunity to reduce risks associated with the toxicity of particles ejected from the gases that form during thermal runaway (TR) in lithium-ion battery cells placed in battery systems. The aim of this thesis is to identify potential materials for particle filtration from these gases, investigate the performance of the chosen materials in an experiment, and suggest materials for future studies. The filter material is intended to sit by the vent in the battery pack. In total 5 filters were chosen for the experiments, where 3 of those were quartz microfibre filters and 2 were glass microfibre filters. The filters were sandwiched between steel plates with a hole, placed 40 cm above the battery cell vent. The battery cells were triggered into thermal runaway, and the filters were placed in the direct path of ejected particles in order to test their thermal resistance and particle retention capabilities. The filters were characterized using weighing, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. From an initial test, the glass fibre filters were deemed not sufficient enough in terms of thermal resistance to continue being tested. The quartz microfibre filters varied in terms of thermal resistance, where they at times burned away and other times remained intact. This was largely attributed to differences in TRs between the experiments due to varying heating parameters. Qualitatively, the quartz microfibre filters succeeded in catching particles, but it cannot be quantified in this experiment how efficient they were in terms of particle retention. The filters showed potential in an easy application in battery packs, but further research should be done to investigate important factors, such as back pressure from the filters. Furthermore, there are certain materials that could be interesting to trial in the future. These include ceramic materials, sintered metal fibre felts, and ablative materials.

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