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Surface coating on cathode materials for environmental-friendly battery manufacturing
(2025) Jayakumar, Karthik; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Klement, Uta; Sun, Jinhua
An increasing need for sustainable energy has put lithium-ion battery in the forefront of the energy race. Traditional batteries cannot meet the energy demands of the future. Moreover, the use of toxic N-Methyl-2-pyrrolidone (NMP) solvent causes high energy consumption, high cost, and environmental concern of the current battery manufacturing process. In order to eliminate the use of NMP solvent during the electrode processing, here the aim of the project is to modify the surface of cathode material and make it favourable for the water-based electrode processing. Considering the stability issue of cathode in water, graphene, which is impermeable to water, was used as coating materials to protect the surface of cathode material. In addition, introducing graphene in the Li-ion battery improves the performance of the battery as it enhances the conductivity and increases the surface area. The graphene-coated cathode materials were characterized by Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA). The preliminary results demonstrated that the graphene coating could improve the cycling stability and increase the capacity of the lithium-ion battery.
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The suitability of placing batteries near the hull sides from a collision and safety perspective: Based on statistics and simulation data
(2024) Pedersen, Magne; Perryd Mattsson, Johanna; Chalmers tekniska högskola / Institutionen för mekanik och maritima vetenskaper; Chalmers University of Technology / Department of Mechanics and Maritime Sciences; Olindersson, Fredrik; Hogström, Per
The ambition to decrease global greenhouse gas emissions is more prevalent than ever, and all industries must do their part to reach that goal. The shipping industry plays a vital role, as a large part of the international transport is being done by ships. There are many ideas and potential solutions on how to reduce the emissions of carbon dioxide from the shipping industry, and those are largely focused on alternative fuel types. Building ships that use batteries as an energy source for propulsion is a concept that is evolving more and more, but it does come with limitations, which are most obvious when it comes to the range of operation and the infrastructure needed to charge those batteries. To expand the range of operation of the ship it can be tempting to make use of every available space to store batteries, for example spaces close to the side casing or within the double hull, but the reason why the space is empty to begin with, or is used for some other purpose, is often due to the safety or stability of the vessel. The spaces that are constructed from a safety perspective are often found around tanks that can contain sensitive cargo or bunker, like chemicals and oil, which could damage the environment if they were to leak out in case of an accident where the hull would be damaged. Batteries are prone to catch fire if they are short circuited due to deformation, therefore placing batteries in spaces that can be exposed to deformation in a collision carries a potential risk, since a potential fire can lead to more substantial damage on the ship than what the collision alone would have made. This study aims to answer if it is appropriate to place batteries where they risk being hit in a collision with another ship, the sea bottom, or a berth. Statistical and simulation data regarding hull damages, accident distribution, and a battery’s resilience against deformation is compiled in a systematic literature review and then used to create a risk analysis on the appropriate placement of batteries. The results show that battery cells can only be deformed by a few millimetres before the cell fails, meaning that the risk of fire is high in a collision if the deformation would reach the batteries.
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Electrical machine initial design and computational tool
(2025) Ulvekar, Akash Chandrakant; Shenoy, Koushik Damodara; Chalmers tekniska högskola / Institutionen för mekanik och maritima vetenskaper; Chalmers University of Technology / Department of Mechanics and Maritime Sciences; Sedarsky, David; Radecki, Przemyslaw
Electric and hybrid electric vehicles widely use Interior Permanent Magnet Synchronous Machines (IPMSM) due to their high torque and power densities. The initial design phase of these electrical machines are critical as they affect the performance, efficiency and costeffectiveness. This thesis explores the development and application of a Python-based computational tool for the initial design of IPMSMs, aiming to achieve optimal machine performance while reducing dependency on iterative Finite Element Method (FEM) solutions. The scope of the research was to develop a robust framework that bridges theoretical design principles with practical computational methods, aiding innovation in electrical machine engineering. An analytical approach was adopted for the preliminary design, focusing on the relationship between machine sizing and performance parameters. Preliminary designs were derived using geometrical constraints and mathematical equations. These designs were validated through Magnetic Equivalent Circuit (MEC) models and sensitivity analysis, with results further corroborated by FEM simulations. The study is centered on two case studies: a MotorCAD template and a journal model. The Python tool demonstrated high accuracy, with sizing parameters closely matching those from MotorCAD and the journal model. Sensitivity analysis was conducted to evaluate the impact of variations in air-gap thickness, magnet width, pole-arc to pole-pitch ratio, and magnet strength on machine performance. The results showcased consistent trends between the Python tool and MotorCAD, emphasizing the tool’s reliability and robustness. The computational tool made it computationally efficient by enabling rapid prototyping and reduced iteration time. This work highlights how the tool can efficiently and accurately design IPMSM, providing a solid foundation for future advancements in electrical machine engineering.
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Evaluating the anti-icing performance of Hydronic Heating system in pedestrian pavement
(2024) Ali, Aboobakkar Nakeeb; Salian, Mokshith Yadava; Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE); Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE); Johansson, Pär; Mirzanamadi, Raheb
This thesis explores the performance and feasibility of using Hydronic Heating Pavement (HHP) systems for anti-icing and solar energy harvesting on pedestrian pathways and roadways. Two test sites were selected for analysis: the E18 motorway in Östersund and a pedestrian pathway in Gothenburg. The study employed numerical modeling using COMSOL Multiphysics 6.2 to simulate surface temperatures and assess energy requirements. Data including air temperature, dew point, wind speed, precipitation, and radiation were collected from local sources and used to validate the models. The numerical simulations demonstrated that, without heating, the road surface in Östersund experienced up to 2,121 hours of slippery conditions annually, whereas the installation of heating pipes reduced this to 332 hours in Gothenburg’s pedestrian pathway. The annual energy required for anti-icing the pedestrian pathways was calculated to be 62.4 kWh/m²/year, with a mean heat flow of 481.3 W/m from a single pipe. Sensitivity analysis revealed that factors such as pipe distance, thermal conductivity, and fluid temperature significantly impacted system performance. For instance, increasing the pipe spacing doubled the number of slippery hours, while higher thermal conductivity and absorptivity reduced them. Comparisons between roads and pedestrian pathways showed that pedestrian pathways required significantly less energy (seven times lower) due to their narrower width. The results indicate that solar energy harvesting alone is more than sufficient to meet the system’s energy requirements, providing up to five times the total annual energy needed when optimized during the summer months. This study concludes that the hydronic heating pavement system demonstrates significant potential in enhancing safety and minimizing icy conditions on pedestrian pathways. Furthermore, the renewable solar energy harvested is capable of fully supporting the operation of HHP system without any additional inputs.
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Extension of the EU Emission Trading System to maritime transportation: Assessing the perception and impacts on the European container shipping industry
(2024) Larsson, Daniel; Heljemo, Joel; Chalmers tekniska högskola / Institutionen för mekanik och maritima vetenskaper; Chalmers University of Technology / Department of Mechanics and Maritime Sciences; Granhag, Lena; Thomassen, Christopher
While being a cornerstone in global trade and being one of the larger contributors to global emissions, container shipping is facing substantial challenges in terms of adopting sustainable energy practices. To combat this current landscape, and provide incentives for the shipping industry to become more sustainable, some initiatives have been introduced, where the EU Emission Trading System (EU ETS) has surfaced as one of these international initiatives. With a focus on actors active within European waters, this study evaluates the EU ETS regulation’s potential effects on the European container shipping industry, how it is perceived by actors within the industry, as well as determining its overall effectiveness in reducing CO2 emissions. Through interviews with international shipping companies and other knowledgeable actors, insights were gathered to provide a greater understanding of the challenges and opportunities arising from the extension of the EU ETS within maritime shipping. The findings of this study imply that actors within the European container shipping industry are positive to regulations such as the EU ETS, and evidently, that something was needed to be done to address these types of issues. Secondly, it is suggested that the competitive landscape between maritime and other modes of transportation will most likely not be altered, at least on a global scale. Thirdly, there are implications that shipping companies may utilize methods to avoid the regulation, such as optimizing routes and transferring the additional cost to shippers. The EU ETS is seen as a potential answer to reducing the cost gap between fossil and alternative fuels, but this study indicates that there are reasons to question the regulation’s overall effectiveness and its ability to reach its goal.