In this paper, I will argue against the position of Carol Hay, who asserts that the oppressed have an obligation against oppression and that the bare minimum of this obligation is to resist internally. I will demonstrate that resisting internally leaves space for the oppressed to affirm the oppressors' false beliefs. Affirming the oppressor's false belief causes the oppressed person to disrespect themself. In order to understand why we must first understand what things contribute to our self-respect. Our ability to respect ourselves depends on many factors, but I will focus on two specifically. The first is our internal/self-image; this is how we see ourselves. The second is our external image; this is how we think people see us. One way we can disrespect ourselves is by causing conflict between these two elements, which undermines our self-respect. Hay's account is grounded on the oppressed person respecting themself. Therefore, if an oppressed person can disrespect themself while meeting the bare requirements of the duty to resist oppression, then we need to reconsider the bare minimum of the obligation to resist oppression. / Master of Arts / In this paper, I will argue against the position of Carol Hay, who asserts that the oppressed have an obligation against oppression and that the bare minimum of this obligation is to resist internally. I will demonstrate that resisting internally leaves space for the oppressed to affirm the oppressors' false beliefs. Affirming the oppressor's false belief causes the oppressed person to disrespect themself. In order to understand why we must first understand what things contribute to our self-respect. Our ability to respect ourselves depends on many factors, but I will focus on two specifically. The first is our internal/self-image; this is how we see ourselves. The second is our external image; this is how we think people see us. One way we can disrespect ourselves is by causing conflict between these two elements, which undermines our self-respect. Hay's account is grounded on the oppressed person respecting themself. Therefore, if an oppressed person can disrespect themself while meeting the bare requirements of the duty to resist oppression, then we need to reconsider the bare minimum of the obligation to resist oppression.

The objective of this report was to implement battery cycling and an intermittent current interruption (ICI) method for determining battery resistance into a simple lithium-ion battery model in the finite element methods (FEM) program COMSOL Multiphysics, andevaluate how accurately the model reflects the behaviour of voltage and internal resistance with respect to experimental results. The ICI technique consists of repeating the steps of first having a longer charging period and then having a short current interruption, where the internal resistance is calculated from the voltage drop that occurs when the current is turned off. The model was evaluated against measurements, made with the same technique (ICI), on assembled NMC-graphite batteries. Codes written in the statistical programming language “R” were used to process the data from both COMSOL and the experiments. Both the batteries and the model were constructed with a reference electrode, to enable measurement of each electrode by itself. The results as documented in this report show that it is possible to simulate the measurement technique in COMSOL, but that both the resistance and voltage profiles differed quite a lot from the behaviour of the tested batteries. The resistance of the positive electrode did however give good results and it was possible to improve the model by changing some parameters. The magnitude of the resistance, which was already quite close, could be improved by changing the porosity and particle size, and the voltage profiles were improved when using voltage-data achieved from the real measurements.

The aim of this master´s thesis is optimalization and methods of measuring the internal resistance of lead acid accumulator. First focus is on the analysis of properties of lead acid accumulators, their construction and negative effects. After that a method of measuring the internal resistance of experimental accumulator is processed. In this thesis practical design of measuring workplace is completed. The frequency analysis of impedance of charging and discharging accumulator is performed. After that the graph of internal resistance for various amplitude intensities, for various signal forms and also for various size of frequencies of alternating current are processed. The result of this thesis is a comparison of graphic works addictions charging and discharging characteristics of lead acid accumulator and determination of optimal amplitude, form and intensity of frequency of alternating current in point when internal resistance is evaluated correctly.

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This work aims on acumulators for hybrid vehicles and deals particularly with research of inner-resistance of the lead-acid batteries. There is a brief characterization of hybrid cars in first part of the tesis. Second part is dealing with design of experimental measurement setup for measurement of lead-acid electrochemical cells. Set of experiments on several cells was performed, description of experiments and results in graphical form are present.

This thesis focuses on the limitations of degradation mechanisms of Lead-Acid batteries, which significantly contributes unequal distribution of current (and therefore internal resistance, charge passed and power loss) on the surface of the electrodes of Lead-Acid battery. The unevenness of distribution of these parameters significantly influences the distribution of current tabs on the electrodes. In this work it was developed realistic model of Lead-Acid battery cell with plate electrodes with different variants of the distribution of current tabs. Measured results obtained in this model were compared with the results found out from the mathematical simulations. Through these simulations, it was possible to take a look deeply into the processes and changes in the electrodes of Lead-Acid batteries during discharge. Goal of this work was for predefined variants of positioning of the current tabs to simulate distribution of current, internal resistance, charge passed and power loss during discharge. Another goal was to compare the different variants and to find the optimal variant of current tabs positioning based on minimizing of unevenness of examined variables distribution.

Det överhängande behovet av att minska utsläppen av växthusgaser för att uppfylla Parisavtalet har väckt ett ökat intresse för elektrifiering som en strategi för att mildra klimatförändringarna. Litiumjonbatterier spelar en central roll vid elektrifiering och har framträtt som det primära alternativet för batteridrivna elfordon. Batteriernas livstidsprestanda är dock en avgörande faktor för att bestämma deras kostnad och miljömässiga hållbarhet. Även om snabbladdning är ett gångbart alternativ för de kunder som vill maximera drifttiden så leder laddning vid höga strömmar till förhöjd åldring genom nedbrytning av elektrodmaterialet och elektrolyten. Nyligen genomförda studier har visat att pulsade laddningscykler kan förlänga livslängden för litiumjonbatterier. Mot bakgrund av detta har denna studie genomförts för att undersöka effekterna av pulsad laddning på bibehållande av kapacitet samt inre motstånd hos litiumjonbatterier. Cylindriska NMC-celler har cyklats med laddningsprofilen PPC-CV (Positive Pulsed Current-Constant Voltage) och deras prestanda har jämförts med motsvarande hos konventionell konstant ström-konstant spänning-laddning (CC-CV). En ny metod utvecklades och implementerades för att utföra en pulsad laddningsprofil inom ett definierat SoC-fönster (State-of-Charge). Testobjekten cyklades kontinuerligt under intervaller om 4 veckor med avbrott för standardiserade referensprestandatester (RPT) för att beräkna standardkapaciteten och det inre motståndet. Därutöver utfördes inkrementell kapacitetsanalys (ICA) och elektrokemisk impedansspektroskopi (EIS) för att utöka analysen. Enligt resultat visar de celler som cyklats med PPC-CV-profilen liknande eller något minskad kapacitetsminskning samt en lägre ökning av internt motstånd efter ungefär 700 ekvivalenta cykler. 0,01-Hz PPC-CV-profilen uppvisade en kapacitetsminskning på 3,65%, 1-Hz PPC-CV-profilen en på 3,75%, 100-Hz PPC-CV- profilen en på 4,06% och CC-CV-profilen en på 4,05%. De interna resistanserna förblev lägre än BOL-mätningarna i PPC-CV-testfallen, medan CC-CV-läget visar en snabbare ökning av internt motstånd. Batteriets hälsotillstånd (SoH) hade dock bara nått 95% under denna testfas, vilket innebär att ytterligare studier krävs för att dra definitiva slutsatser om pulsladdningens effekt på batteriets livslängd. För att ytterligare förstå effekten av pulsade laddningsprofiler på livslängden hos litiumjonbatterier kan textmatrisen utökas till ett bredare spektrum av testförhållanden, såsom temperatur, strömamplitud, arbetscykel och SoC-fönster. / The urgent need to reduce greenhouse gas emissions in order to comply with the Paris Agreement has sparked an increased interest in electrification as a strategy to mitigate climate change. Li-ion batteries play a crucial role in electrification, and have emerged as the primary option for battery electric vehicles. However, their lifetime performance is a critical factor in determining their cost and environmental sustainability. Although fast charging presents a viable option for customers wishing to maximize operational time, charging at high currents accelerate aging through degradation of the electrode material and the electrolyte. Recent studies have found that pulse charging protocols can extend the cycle life of Li-ion batteries. In light of this, this study has been conducted to investigate the effects of pulse charging on the capacity retention and internal resistance of Li-ion batteries. Prismatic NMC Li-ion battery cells were cycled using the Positive Pulsed Current-Constant Voltage (PPC-CV) charging mode, and their performance has been compared to that of conventional Constant Current-Constant Voltage (CC-CV) charging. A novel method was developed and implemented to execute a pulse charging profile within a defined State-of-Charge (SoC) window. The test objects were continuously cycled over intervals of 4 weeks with interruptions for standardized Reference Performance Tests (RPTs) to calculate the stan- dard capacity and internal resistance. In addition, Incremental Capacity Analysis (ICA) and Electrochemical Impedance Spectroscopy (EIS) were performed to ex- tend the analysis. According to results, cells cycled using the PPC-CV mode show similar or slightly reduced capacity fade and a lower increase in internal resistance after roughly 700 equivalent cycles. The 0.01-Hz PPC-CV mode exhibited a capacity fade of 3.65%, the 1-Hz PPC-CV mode 3.75%, the 100-Hz PPC-CV mode 4.06% and the CC-CV mode 4.05%. Internal resistances remained lower than the beginning of life measurements in the PPC-CV test cases, while the CC-CV mode shows a quicker increase in internal resistance. However, the battery State-of-Health (SoH) had only reached 95% during this testing phase, requiring further study to draw definitive conclusions regarding the impact of pulse charging on battery life performance. To further understand the impact of pulsed charging modes on Li-ion battery life performance, the text matrix may be extended to incorporate a broader range of test conditions, such as temperature, current amplitude, duty cycle and State-of-Charge (SoC) window.

Molecular dynamics simulation was used to study ion permeation through different membrane proteins embedded in a lipid bilayer (DMPC) with different saline solutions. The potential of mean force (PMF) for ion transport was obtained by umbrella sampling simulations. A revised MacKerell force field for tryptophan residues was studied using gramicidin A (gA) channel as a test model. The revised force field contribution to the Na+ PMF was consonant with the prediction from the experimental results, but in stark contrast to the prediction of the CHARMM force field, version 22, for the tryptophan side-chain. A new grid-based correction map algorithm by MacKerell group, called CMAP, was introduced into the CHARMM force field, version 31. The CMAP algorithm focused on optimizing phi, psi dihedral parameters for the peptide backbone. The CMAP corrections reduced the excessive translocation barrier. Decomposition demonstrated the reduction in the translocation barrier was due to effects on the K+ PMFH2O rather than on K+ PMFgA. The presence of negatively charged sulfonate group at the entrance and exit of the gA channel affected the depth and the location of the highly occupied sites. The negatively charged sulfonate group produced a strong attraction for the cations in the bulk towards the channel mouth. In the M2 transmembrane domain channel (M2-TMD), three M2-TMD structures were studied, differing only in whether the selectivity-filter (four His37 side-chains) was uncharged, +2 charged, or +3 charged. M2-TMD structural properties were compared with the structural properties of other models extracted from NMR and X-ray studies. The spontaneous cation and anion entry into the charged selectivity-filter was different from that into a neutral selectivity-filter. Cl- ions had a lower free-energy barrier in the selectivity-filter than either Na+ or NH4+ ions through the M2-TMD channel. NH4+ ions had a lower free-energy barrier in the selectivity-filter than Na+ ions. Based on accessible rotamer conformations, a revised conductance mechanism was proposed. In this conductance mechanism, the His37 side-chain functioned as an acceptor and donor group, whereas the Trp41 side-chain functioned as a carrying group.