Lidé

Ing. Anna Pražanová

Všechny publikace

Ultrathin organic dye layers for sensitisation of silicon

  • DOI: 10.59957/jctm.v59.i2.2024.1
  • Odkaz: https://doi.org/10.59957/jctm.v59.i2.2024.1
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Combination of affordable organic dyes of high quantum yield with silicon can be an interesting way fordevelopment of highly efficient thin film photovoltaic cells utilizing silicon sensitisation. This work is focused on investigating the energy transfer processes including photon tunnelling from photosensitive molecules of BASF R305 high quantum yield dye to silicon substrate. Energy transfer from dye molecules to silicon substrate is evaluated by measuring the quenching of molecular photoluminescence lifetime using time-correlated single photon counting (TCSPC) technique. Energy transfer is further studied in dependence on dye layer thickness. The results can be useful for further studies leading to design of ultrathin silicon solar cells.

Pre-Recycling Material Analysis of NMC Lithium-Ion Battery Cells from Electric Vehicles

  • DOI: 10.3390/cryst13020214
  • Odkaz: https://doi.org/10.3390/cryst13020214
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Environmental concerns push for a reduction in greenhouse gas emissions and technologies with a low carbon footprint. In the transportation sector, this drives the transition toward electric vehicles (EVs), which are nowadays mainly based on lithium-ion batteries (LIBs). As the number of produced EVs is rapidly growing, a large amount of waste batteries is expected in the future. Recycling seems to be one of the most promising end-of-life (EOL) methods; it reduces raw material consumption in battery production and the environmental burden. Thus, this work introduces a comprehensive pre-recycling material characterization of waste nickel-manganese-cobalt (NMC) LIB cells from a fully electric battery electric vehicle (BEV), which represents a basis for cost-effective and environmentally friendly recycling focusing on the efficiency of the implemented technique. The composition of the NCM 622 battery cell was determined; it included a LiNi0.6Co0.2Mn0.2O2 spinel on a 15 μm Al-based current collector (cathode), a graphite layer on 60 μm copper foil (anode), 25 μm PE/PVDF polymer separator, and a LiPF6 salt electrolyte with a 1:3 ratio in primary solvents DMC and DEC. The performed research was based on a series of X-ray, infrared (IR) measurements, gas chromatography–mass spectrometry (GC-MS), and inductively coupled plasma–optical emission spectrometry (ICP-OES) characterization of an aqueous solution with dissolved electrolytes. These results will be used in subsequent works devoted to optimizing the most suitable recycling technique considering the environmental and economic perspectives.

Second-Life of Lithium-Ion Batteries from Electric Vehicles: Concept, Aging, Testing, and Applications

  • DOI: 10.3390/en16052345
  • Odkaz: https://doi.org/10.3390/en16052345
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    The last decade has seen a significant increase in electromobility. With this trend, it will be necessary to start dealing with the subsequent recycling and disposal of electric vehicles, including the batteries. Currently, the battery is one of the most expensive components of an electric vehicle, which in part hinders their sufficient competitiveness with the internal combustion engine. Furthermore, the lifetime of a battery for use in an electric vehicle is assumed to be 8–10 years/160,000 km, after which the battery capacity drops to 80% of the initial capacity. However, it transpires that a battery at the end of its life in an electric vehicle does not need to be disposed of immediately, but can be used in other applications wherein the emphasis is not so strictly on an excellent power and capacity capability related to its volume or weight. Thus, reusing batteries can help reduce their cost for use in electric vehicles, increase their utility value, and reduce the environmental impact of batteries. This paper discusses methods for researching battery aging in electric vehicles, testing methods for batteries during the transition from first life to second life, and prospective battery second-life use and its specifics. The main contribution of this perspective article is to provide a comprehensive view of the current state of second-life batteries and an overview of the challenges that need to be overcome in order to use them on a large industrial scale.

Techno-Environmental Evaluation of Recycling Pretreatment of Cylindrical Lithium-Ion Battery: Discharging via Salt-Based Solution

  • DOI: 10.1109/ISSE57496.2023.10168348
  • Odkaz: https://doi.org/10.1109/ISSE57496.2023.10168348
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    The popularity of lithium-ion batteries (LIBs) as crucial power sources has increased in recent years. LIBs represent a perspective technology for recycling because they comprise a high portion of valuable metals, such as nickel, manganese, cobalt, or lithium, and other metals, including aluminium, copper, and iron. Battery discharging represents an essential step in end-of-life (EOL) pretreatment, as it reduces the risk of fire or explosion in further processing. As a simple, quick, and inexpensive technique, an electrochemical discharging process via salt-based solutions is preferred for cylindrical cells. Nevertheless, it is necessary to consider the composition of obtained waste products and the possible environmental risks leading to their safe and non-hazardous EOL processing. This work evaluated discharging efficiency and environmental perspective for cylindrical LIB cells, which were treated using NaCl solution. All battery cells were discharged to the safe voltage limit (0.75 V) within 24 hours. Major organic components, including volatile solvents with high toxic hazards, such as carbonic acid esters, methyl salicylate, and propanoic acid esters, were identified in the waste solutions using gas chromatography with mass spectrometry (GC-MS). Moreover, the metal proportion in the solution was determined using inductively coupled plasma - optical emission spectrometry (ICP-OES) analysis; it is recommended to recover metals from the wastewater before EOL or cleaning treatment.

EKONOMICKÁ NÁROČNOST RECYKLACE LITHIUM-IONTOVÝCH BATERIÍ Z ELEKTROMOBILŮ

  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Emissions reduction has been tightened worldwide, especially in automotive. Electric vehicles (EVs) are a suitable solution that can meet the strict requirements in CO2 production and high user torque and speed requests. Therefore, a significant increase in demand for EVs has occurred. This growing trend results in increased production of new vehicles, raw materials consumption, and the number of waste vehicles and batteries on the market. Solution methods are being sought: the recycling process is one of the most promising. This work provides a simplified overview of the economic evaluation of the recycling process of spent lithium-ion batteries from EVs in conditions of the Czech Republic. The described technique evaluates a combination of the pyrometallurgical and hydrometallurgical methods (with the process efficiency above 95 %) and the high quality of output products. Moreover, this work presents future scenarios considering the changes due to EU legislation.

Evolution of Lithium-Ion Battery Model Parameters for CubeSats Missions

  • Autoři: Ing. Anna Pražanová, MSc. Václav Knap, Ph.D.,
  • Publikace: 2022 45th International Spring Seminar on Electronics Technology (ISSE). New York: IEEE Press, 2022. International Spring Seminar on Electronics Technology (ISSE). ISSN 2161-2536. ISBN 978-1-6654-6589-2.
  • Rok: 2022
  • DOI: 10.1109/ISSE54558.2022.9812774
  • Odkaz: https://doi.org/10.1109/ISSE54558.2022.9812774
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    The popularity of CubeSats has grown in the last few years. CubeSats are small-sized, low-weight satellites commonly used in low Earth orbit for remote sensing or communications. Their most considerable benefits are their high flexibility, quick lead time, and significantly lower price than 'classical' satellites, due to their vast use of commercial off-the-shelf components. Lithium-ion batteries are being used as energy storage within these components. Batteries are necessary for the spacecraft; they supply energy when there is not enough generation from solar panels, especially during eclipses. The batteries undertake a series of operations during missions in various conditions that influence their lifetime and performance. The performance of these batteries can be modelled via an electrical-circuit model. Thus, a set of characterization and degradation tests considering cycling aging were performed to identify the cell behaviour throughout an expected battery life in a CubeSat. The aging trends of the battery model parameters based on the provided parametrization procedure were observed and evaluated. Moreover, the developed model reaches high accuracy for a mission profile with the root-mean-square-error below 9 mV.

Literature Review, Recycling of Lithium-Ion Batteries from Electric Vehicles, Part I: Recycling Technology

  • DOI: 10.3390/en15031086
  • Odkaz: https://doi.org/10.3390/en15031086
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    During recent years, emissions reduction has been tightened worldwide. Therefore, there is an increasing demand for electric vehicles (EVs) that can meet emission requirements. The growing number of new EVs increases the consumption of raw materials during production. Simultaneously, the number of used EVs and subsequently retired lithium-ion batteries (LIBs) that need to be disposed of is also increasing. According to the current approaches, the recycling process technology appears to be one of the most promising solutions for the End-of-Life (EOL) LIBs—recycling and reusing of waste materials would reduce raw materials production and environmental burden. According to this performed literature review, 263 publications about “Recycling of Lithium-ion Batteries from Electric Vehicles” were classified into five sections: Recycling Processes, Battery Composition, Environmental Impact, Economic Evaluation, and Recycling & Rest. The whole work reviews the current-state of publications dedicated to recycling LIBs from EVs in the techno-environmental-economic summary. This paper covers the first part of the review work; it is devoted to the recycling technology processes and points out the main study fields in recycling that were found during this work.

Literature Review, Recycling of Lithium-Ion Batteries from Electric Vehicles, Part II: Environmental and Economic Perspective

  • DOI: 10.3390/en15197356
  • Odkaz: https://doi.org/10.3390/en15197356
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Lithium-ion batteries (LIBs) are crucial for consumer electronics, complex energy storage systems, space applications, and the automotive industry. The increasing requirements for decarbonization and CO2 emissions reduction affect the composition of new production. Thus, the entire automotive sector experiences its turning point; the production capacities of new internal combustion engine vehicles are limited, and the demand for electric vehicles (EVs) has continuously increased over the past years. The growing number of new EVs leads to an increasing amount of automotive waste, namely spent LIBs. Recycling appears to be the most suitable solution for lowering EV prices and reducing environmental impacts; however, it is still not a well-established process. This work is the second part of the review collection based on the performed literature survey, where more than 250 publications about “Recycling of Lithium-ion Batteries from Electric Vehicles” were divided into five sections: Recycling Processes, Battery Composition, Environmental Impact, Economic Evaluation, and Recycling and Rest. This paper reviews and summarizes 162 publications dedicated to recycling procedures and their environmental or economic perspective. Both reviews cover the techno-environmental economic impacts of recycling spent LIBs from EVs published until 2021

Lithium-ion battery module-to-cell: disassembly and material analysis

  • DOI: 10.1088/1742-6596/2382/1/012002
  • Odkaz: https://doi.org/10.1088/1742-6596/2382/1/012002
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Lithium-ion batteries (LIBs) are one of the most popular energy storage systems. Due to their excellent performance, they are widely used in portable consumer electronics and electric vehicles (EVs). The ever-increasing requirements for global carbon dioxide CO2 emission reduction inhibit the production of new combustion vehicles. Thus, the demand for EVs increases, as well as the number of spent LIBs. Due to increases in raw materials saving and reduction in energy and environmental impacts, recycling is one of the most promising solutions for end-of-life (EOL) treatment for spent LIBs. This work describes the first step in recycling the LIBs nickel-manganese-cobalt (NMC) based module from a full battery electric vehicle (BEV) holding its high recycling efficiency and considering the process costs and environmental impact. This paper is devoted to module-to-cell disassembly, discharge state characterization measurements, and material analysis of its components based on x-ray fluorescence (XRF) and diffraction (XRD).

Lithium-Ion NMC Batteries: Chemical Toxicity Reflection of Wastewater and Scrap

  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    The ever-increasing requirements for global carbon dioxide CO2 emission reduction decrease the production of new internal combustion engine vehicles (ICEVs). On the contrary, the demand for electric vehicles (EVs) increases along with the number of spent lithium-ion batteries (LIBs). Recycling LIBs seems to be one of the most promising options for end-of-life (EOL) treatment solutions; however, many process effects of currently used battery compounds are still being addressed, e.g., the safety and potential risks of wastewater, battery scrap, or leaks into the air. In this work, the LIB nickel-manganese-cobalt (NMC) cell electrolyte was characterized in wastewater using gas chromatography with mass spectrometry (GC-MS), inductively coupled plasma with optical emission spectrometer (ICP-OES), and the residues of toxic substances bound to nm-μm valuable metal particles in battery scrap were determined by x-ray fluorescence (XRF).

Offline State-of-Health Estimation Method for Lithium-Ion Batteries in LEO CubeSats

  • Autoři: MSc. Václav Knap, Ph.D., Ing. Anna Pražanová, Stroe, D.-I.
  • Publikace: 43. Nekonvenční zdroje elektrické energie. Praha: Česká elektrotechnická společnost, 2022. p. 61-64. ISBN 978-80-02-02972-4.
  • Rok: 2022
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    State-of-health (SOH) estimation is an essential but challenging functionality for batteries. In this work, a SOH estimation for Lithium-ion batteries in CubeSats is in focus. A proposed method is based on offline model parameter identification from satellite telemetry. Its laboratory performance was 2.26 % and 0.74 % root-mean-square-error for capacity and resistance, respectively.

Understanding the Effect of Reflow Profile on the Metallurgical Properties of Tin–Bismuth Solders

  • DOI: 10.3390/met12010121
  • Odkaz: https://doi.org/10.3390/met12010121
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Sn–Bi alloys are desirable candidates for soldering components on printed circuit boards (PCBs) because of their low melting point and reduced cost. While certain tin–bismuth solders are well characterized many new alloys in this family have been developed which need proper characterization. The following study looks at the behavior of four different Sn–Bi alloys—traditional 42Sn58Bi and 42Sn57Bi1Ag and two new tin–bismuth alloys—in solder paste during the reflow soldering process. Each alloy was processed using different reflow profiles that had varying times above liquidus (TALs) and peak temperatures. The PCBs were then analyzed to see how the processing variables influenced wetting, voiding, microstructure, intermetallic layer composition, and thickness. After analysis, the PCBs were then subjected to thermal cycling experiments to see how reflow profile impacted microstructure evolution. The results demonstrated that reflow profile affects properties such as metal wetting and voiding. It does not however, greatly impact key metallurgical properties such as intermetallic layer thickness.

Electrical Circuit Model of Lithium-Ion Batteries and Revisiting of Its Parametrization Procedures

  • DOI: 10.1149/10501.0487ecst
  • Odkaz: https://doi.org/10.1149/10501.0487ecst
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Nowadays, Lithium-ion batteries are as the most preferable technology for consumer electronics. They found their way also to electric vehicles or even satellites, mainly due to their high energy density and long life. In the applications, the batteries require a battery management system for safe and optimal operation. Often, state estimation functionalities (as state-of-charge or state-ofhealth) require a running battery model. Therefore, an electrical circuit model (ECM) that accurately captures a battery behavior in suitable complexity is needed. This paper presents a three steps parametrization technique of ECM for Lithium-ion batteries based on laboratory experiments. Furthermore, an analysis of SOC and temperature dependence of battery parameters has been conducted. The developed ECM is validated, and its accuracy is evaluated by Root Mean Square Error (RMSE) and Maximal Absolute Error (MaE).

Novel Electrical Insulation Materials - Mechanical Performance of 3D Printed Polylactic Acid

  • DOI: 10.1109/Diagnostika49114.2020.9214627
  • Odkaz: https://doi.org/10.1109/Diagnostika49114.2020.9214627
  • Pracoviště: Fakulta elektrotechnická, Katedra elektrotechnologie
  • Anotace:
    The aim of this work was to evaluate the mechanical and thermomechanical properties of structures prepared by 3D printing from biodegradable thermoplastic polyester PLA (Polylactic Acid). PLA structures and their manufacture by 3D printing can be a cost-saving and ecological alternative to the current production of insulation systems, e.g. condenser bushings or substrates for printed circuit boards. For further practical application, the knowledge of the change of mechanical and thermal properties in dependence on process parameters is necessary. In this research, PLA test samples were first prepared at different printing speeds and nozzle temperatures. Then, they were characterized by thermomechanical analysis (TMA), dynamic mechanical analysis (DMA), and tensile tests. The data showed that the decrease of printing temperature remarkably increased the dimension change evaluated from TMA measurement of 3D printed structures. On the other hand, no significant differences were found between samples printed with different printing speeds. Our results should lead to a better understanding of how to set up the 3D printing process properly.

Za stránku zodpovídá: Ing. Mgr. Radovan Suk