En konceptlösning för ett elektrovinningssystem utvecklas baserat på Glenngårds (2019) tidigare arbete. Arbetet är genomfört så att det besvarar tre frågor om en potentiell konceptlösning. Frågeställningarna inkluderar vilka krav som behöver uppfyllas, design av en passande arkitektur och hur vissa konceptparametrar kan verifieras. Krav formuleras i huvudsak baserat på Glenngårds parametrar; säkerhet, kvalitet, användarvänlighet, enkelhet att tillverka, montera, underhålla systemet, kostnadseffektivitet och användning av standardiserade komponenter. Konceptet som genereras är baserat på att använda en elektrolytbehållare kring vilken andra system är fästa eller indränkta. Designen tillåter en grad av automatisering. En bruksprocess för konceptet beskrivs, relevanta komponenter förklaras och vidare utveckling föreslås. En lista med föreslagna tester för verifikation med hjälp av prototypen är också given. / A concept solution for an electro winning system is developed based on the previous work done by Glenngård (2019). This project is made to answer three questions about a potential concept solution, including what requirements need to be fulfilled, design of a suitable architecture and how to verify certain parameters of the concept. Requirements are formulated mainly based on Glenngård’s parameters; safety, quality requirements, ease of use, ease of manufacturing, ease of assembly, ease of maintenance, cost efficiency and use of standardized components. The concept that is generated is based on a single electrolyte container around which surrounding systems are attached or immersed. The design allows a degree of automatization. A process of use is described, relevant components are explained, and further developments are suggested. A list of suggested tests to be carried out for verification using a prototype is also provided.

Solar energy is increasingly being considered a promising solution to reduce the emissions of CO2 and green house gas. The performance of solar collectors largely depends on the ability to absorb incoming solar radiation with minimal thermal radiation losses. To weigh the potential absorbed energy to thermal losses, the performance criterion (PC) can be used, calculated as PC =α−xε, where α is absorptance, ε is emittance and x is a scaling factor < 1. It has been shown by G. Vargas et al. that Co-Cr alloys excibit great potential (α = 0.98 and ε = 0.03) for use in solar concentrators. The main goal of this project is to quantify the impact of key factors (controlled input variables) on an electroplating process of Co-Cr alloys, using the design of experiment (DOE) methodology. It is part of an ongoing collaboration between Absolicon and the physics department at Umeå university. Six factors were investigated using a fractional factorial (FrF) design. Data was collected through a series of experiments where stainless steel substrates were electroplated with Co-Cr alloys. The resulting samples were analyzed in terms of α and ε as well as the quality of deposition (QD). Using the experimental results, three models were made in a DOE-software called MODDE. Models are used to correlate the factors with each response, i.e. α, ε and QD. Ideally the predictive power of the models (Q2) should be as high as possible, and at least > 0.5. The analysis of variance (ANOVA) test was used to determine the significance of the models. Based on the models, the ’Optimizer’ tool in MODDE was used to predict two set of optimum factor settings, producing two samples, S1 and S2. S1 and S2 were evaluated in terms of α, ε and QD as well as chemical composition and structural properties of the coatings. The predictive power of the models was 0.49 for α, 0.38 for ε and 0.53 for QD. The predictive power of the models were therefore limited. ANOVA-test showed that the models for α and QD were statistically significant. For all three responses the significant effects were mostly two factor interactions. All three models showed significant lack of fit (model error) as a result of high reproducibility. S1 had the best PCAbsolicon (performance criterion for Absolicons solar collectors) of all samples with 0.858. S2 was not as good, even though it was predicted to have a higher value of PCAbsolicon by MODDE. EDS, XPS and SEM measurements of samples S1 and S2 showed that the two samples were very similar in terms of chemical composition. The main difference was that the coating of S1 was more porous, and also thicker than S2, 0.81 μm compared to 0.26 μm. Even though the models showed some predictive capabilities, the impact of the factors could not be fully determined. That is due to the nature of the FrF-design, which cannot accurately determine two-factor interactions.

As part of the global work towards reducing CO2 emissions, all vehicles needs to be electrified, or fueled by green fuels. Batteries have already revolutionised the car market, but fuel cells are believed to be a key energy conversion system to be able to electrify also heavy duty vehicles. The type of fuel cell commercially available for vehicles today is the polymer electrolyte membrane fuel cell (PEMFC), but for it to be able to take a larger market share, the cost must be reduced while sufficient lifetime is ensured. The PEMFC is a system containing several components, made of different materials including the polymer membrane, noble metal catalyst particles, and metallic bipolar plate. The combination of different materials exposed to elevated temperature, high humidity and low pH make the PEMFC components susceptible to corrosion and degradation. The noble metal catalyst is one of the major contributors to the high cost. In this work, the latest research on new catalyst materials for PEMFCs are overviewed. Furthermore, electrodeposition as a simple synthesis route to test different Pt-alloys for the cathode catalyst in the fuel cell is explored by synthesis of PtNi and PtNiMo. The gas diffusion layer of the PEMFC is used as substrate to reduce the number of steps to form the membrane electrode assembly. In addition to cheaper and more durable materials, understanding of how the materials degrade, and how the degradation affects the other components is crucial to ensure a long lifetime. Finding reliable test methods to validate the lifetime of the final system is necessary to make fuel cell a trusted technology for vehicles, with predictable performance. In this work, commercial flow plates are studied, to see the effect of different load cycles and relative humidities on the corrosion of the plate. Defects originating from production is observed, and the effect of these defects on the corrosion is further analysed. Suggestions are given on how the design and production of bipolar plates should be made to reduce the risk of corrosion in the PEMFC. / Som en del av det globala arbetet med at reducera utsläppen av koldioxid måste alla fordon elektrifieras eller tankas med förnybart bränsle. Batterier har redan revolutionerat bilmarknaden, men bränsleceller är en viktig pusselbit för att också elektrifiera tunga fordon. Den typen av bränsleceller för fordon som finns tillgänglig på den kommersiella marknaden i dag är polymerelektrolytbränslecellen (PEMFC). För att PEMFC skall ta en större marknadsandel måste kostnaderna minskas och livslängden förlängas. PEMFC består av ett antal komponenter gjorda av olika material, bland annat polymer membran, ädelmetallkatalysator, och metalliska bipolära plattor. Kombinationen av olika material i tillägg till den höga temperaturen, hög fuktighet och låg pH gör att materialen i bränslecellen är utsatta för korrosion. Ädelmetallkatalysatorn är en av de kostdrivande komponenterna i bränslecellen. I denna studien presenteras en översikt över framstegen inom katalysatormaterial för PEM bränsleceller de senaste två åren. Sedan studeras elektroplätering som en enkel produktionsmetod för nanopartiklar av platina legeringar. Möjligheten att simultant plätera fler metaller, och att använda gasdiffutions-skiktet från bränslecellen som substrat för att reducera antal produktionsteg och därmed reducera kostnader, undersöks. Det möjliggör också snabb testning av olika legeringar för att identifiera den optimala sammansättningen med hög prestanda, lång livslängd och lite platina. I tillägg till att ta fram billigare och tåliga material är det viktigt att förstå hur materialen degraderar och hur degraderingen av ett material påverkar de andra komponenterna. Med den kunskapen kan man utveckla accelererade testmetoder för att bedöma livslängden av hela bränslecellen. Validerade testmetoder är viktigt för att styrka förtroendet till nya teknologier. I denna studien fokuseras det också på korrosion av bipolära plattor, och hur olika lastcykler och fuktnivåer som kan bli applicerad vid accelererad testning påverkar korrosionen. Också effekten av defekter från tillverkningen i den skyddande beläggningen analyseras med hänsyn till korrosion, för att ge mer insikt i hur bipolära plattor kan designas och produceras för att minska korrosionen.

Corrosion can cause devastating damage to materials, and to protect materials from corrosion is crucial, especially in the aeronautical industry. An electroplated Zinc-Nickel coating provides excellent corrosion protection of steel. Electroplating of ZnNi is a sensitive process which needs frequent and fast feedback controls and adjustments of the process electrolyte. A common process control for electroplating processes is the Hull cell test, which is investigated in this study. The Hull cell test is a lab scaled electroplating unit, which spans a wide range of current densities. It is crucial to establish the relation between process parameters in the Hull cell and the resulting coating characteristics in order to implement it as a process control. The purpose of this study is to establish these relations for the ZnNi electroplating process, and evaluate if the Hull cell test is a suitable process control for this process. How the process parameters; current density, temperature, metal ion concentration, and carbonate contaminations affect the coating characteristics; visual appearance, thickness, composition, surface structure, and phase content has been established. Influence on the coatings were mainly seen at current densities higher and lower than the ones used in production. This demonstrates the strength of the Hull cell test for early detection of process deviations. Coating thickness and composition was measured with X-ray fluorescence. However, the composition values for thin coatings were discovered to be inaccurate, which was avoided by increasing the plating time. Once addressed, the Hull cell test is suitable as a process control for the electroplating process of ZnNi.