Lidé

MSc. Václav Knap, Ph.D.

Všechny publikace

Direct Recycling Technology for Spent Lithium-Ion Batteries: Limitations of Current Implementation

  • DOI: 10.3390/batteries10030081
  • Odkaz: https://doi.org/10.3390/batteries10030081
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    The significant deployment of lithium-ion batteries (LIBs) within a wide application field covering small consumer electronics, light and heavy means of transport, such as e-bikes, e-scooters, and electric vehicles (EVs), or energy storage stationary systems will inevitably lead to generating notable amounts of spent batteries in the coming years. Considering the environmental perspective, material resource sustainability, and terms of the circular economy, recycling represents a highly prospective strategy for LIB end-of-life (EOL) management. In contrast with traditional, large-scale, implemented recycling methods, such as pyrometallurgy or hydrometallurgy, direct recycling technology constitutes a promising solution for LIB EOL treatment with outstanding environmental benefits, including reduction of energy consumption and emission footprint, and weighty economic viability. This work comprehensively assesses the limitations and challenges of state-of-the-art, implemented direct recycling methods for spent LIB cathode and anode material treatment. The introduced approaches include solid-state sintering, electrochemical relithiation in organic and aqueous electrolytes, and ionothermal, solution, and eutectic relithiation methods. Since most direct recycling techniques are still being developed and implemented primarily on a laboratory scale, this review identifies and discusses potential areas for optimization to facilitate forthcoming large-scale industrial implementation.

Extending battery life in CubeSats by charging current control utilizing a long short-term memory network for solar power predictions

  • Autoři: MSc. Václav Knap, Ph.D., Bonvang, G.A.P., Fagerlund, F.R., Krøyer, S., Nguyen, K., Thorsager, M., Tan, Z.-H.
  • Publikace: Journal of Power Sources. 2024, 618 1-11. ISSN 0378-7753.
  • Rok: 2024
  • DOI: 10.1016/j.jpowsour.2024.235164
  • Odkaz: https://doi.org/10.1016/j.jpowsour.2024.235164
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Recently, there has been a surge in small satellites and CubeSats. A crucial factor limiting the duration of their missions is the lifespan of their batteries. Typically, batteries are charged immediately when there is sufficient power generated from the solar panels. However, this practice results in additional charging stress and degradation due to unnecessarily high current amplitudes. In this work, a distributed charging strategy based on solar power prediction is proposed to mitigate charging stress and thereby extend battery life, ensuring sufficient charging without jeopardizing spacecraft operation. The proposed method for power generation prediction relies on a Long Short-Term Memory (LSTM) network, trained on GOMX-4A satellite telemetry data. The proposed LSTM method performed an order of magnitude better, with a root mean square error (RMSE) of 0.2274 W, while a baseline prediction utilizing a Seasonal Auto-Regressive Moving Average has an RMSE of 1.2406 W. Using the predicted power generation from the LSTM method, the current is distributed using a proposed charging multiplier control, resulting in 72.0882% reduction in the median charging current. A direct possible impact on lithium-ion batteries was evaluated by employing an electrochemical model from the literature, confirming that the proposed strategy effectively reduces degradation caused by lithium plating. Moreover, the capacity fade in the example scenario at 25 °C was reduced by 0.0849%. The extent of degradation reduction will vary according to the required mission profile, the operational conditions, the specific chemistry, and the type of battery in use. © 2024 Elsevier B.V.

Hydrogen in Automotive: LCA Study

  • DOI: 10.1109/ISSE61612.2024.10603647
  • Odkaz: https://doi.org/10.1109/ISSE61612.2024.10603647
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    This study presents a comprehensive cradle-to-gate Life Cycle Assessment of fuel cell electric vehicles (FCEVs), providing a comparative assessment against alternative and fossil fuel-driven counterparts. The research focuses on hydrogen as a fuel source, emphasizing two key production methods: natural gas reforming and water electrolysis. The scope of the study is set to the Czech Republic environment. Diverse sources of electric generation, such as wind and photovoltaics, are considered to supply the electrolysis process. The energy source mix predictions are set to year 2030 up to 2050. The feasibility of transitioning towards greater utilization of renewable energy sources within the context of privately owned vehicles is investigated in this work. Specifically, the study examines the exact part of the vehicle life cycle, starting with production to the use phase, with a consideration of the car’s lifetime, aiming to provide a nuanced understanding of their environmental footprint and clear comparability with each other. This study highlights the significant potential for reducing the environmental impacts of personal vehicles through the usage of hydrogen. With FCEVs emitting zero direct emissions, the total environmental impact is directly tied to the process of fuel production. Producing hydrogen through electrolysis, particularly when powered by photovoltaic or wind energy can significantly lower its emissions, especially in terms of greenhouse gas emissions.

Lithium-ion (LCO/NMC, NMC, LFP) battery recycling: partial LCA study

  • DOI: 10.1007/s00706-024-03184-6
  • Odkaz: https://doi.org/10.1007/s00706-024-03184-6
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Recycling lithium-ion batteries (LIBs) have become increasingly important in response to expanding electromobility. This paper is focused on evaluating the environmental impacts (EIs) of recycling pre-treatment of three types of LIBs with black mass as its product. A detailed gate-to-gate Life Cycle Assessment study was conducted to obtain EIs of the recycling process. The benefits of LIBs recycling pre-treatment and significant recovery of secondary aluminum for compared battery types are highlighted in the analysis. This paper points out that the varying chemistry of the compared LIBs does not affect the resulting EIs of the recycling pre-treatment procedures.

Review of electrochemical impedance spectroscopy methods for lithium-ion battery diagnostics and their limitations

  • DOI: 10.1007/s00706-023-03165-1
  • Odkaz: https://doi.org/10.1007/s00706-023-03165-1
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Electrochemical impedance spectroscopy (EIS) is a measurement method widely used for non-destructive analysis and diagnostics in various electrochemical fields. From the measured dependence of the battery impedance on the frequency, it is possible to determine the parameters of various equivalent electrical circuit models of the battery. The conventional method of battery measurement using single-sine EIS is currently one of the most widely used methods for the analysis of lithium-ion batteries. However, its most significant disadvantage is the relatively long measurement time. For this reason, there is a growing demand for faster methods using fast-Fourier transform or pseudo-random sequences. A description of various EIS methods applications is provided in this paper.

State-of-Charge Estimation Based on Open-Circuit Voltage Model Considering Hysteresis

  • DOI: 10.1109/ISSE61612.2024.10603756
  • Odkaz: https://doi.org/10.1109/ISSE61612.2024.10603756
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Lithium-ion batteries (LIBs) play a pivotal role in various sectors such as transportation, aerospace, and stationary systems. Accurate estimation of their state-of-charge (SOC) is crucial for efficient utilization within battery management systems. This work presents an enhanced SOC estimation method for LIBs, leveraging both open-circuit voltage (OCV) and hysteresis models. A co-estimation architecture employing two estimators is proposed, firstly focusing on battery model parameter estimation, and secondly utilizing pseudo-OCV instead of voltage measurements as output. This modification offers enhanced accuracy, reduced reliance on extensive laboratory testing, and improved robustness, especially in applications with rapid temperature fluctuations. The proposed method is evaluated through dynamic discharge profile tests across temperature levels ranging from 5 to 45 °C. Root-mean-square errors of SOC estimation for various temperatures were improved from the baseline approach (0.0185-0.0420) down to 0.0090-0.0280 in the proposed approach, showcasing the effectiveness of incorporating hysteresis models into SOC estimation.

Sustainability Challenges: The Circular Economy Dilemma in Lithium-Ion Battery Cell Electrochemical Discharging Processes

  • DOI: 10.1109/ISSE61612.2024.10603724
  • Odkaz: https://doi.org/10.1109/ISSE61612.2024.10603724
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Recycling lithium-ion batteries (LIBs) is crucial for environmental sustainability and resource conservation. However, current recycling procedures, particularly for smaller battery formats, pose several challenges. With the increasing demands of the circular economy for LIB waste treatment, it is essential to identify and address obstacles associated with concurrent processes. Thus, this study focuses on characterizing and examining the dilemmas of electrochemical discharging of cylindrical LIB cells. It primarily examines the quantity and composition of released battery mass from nickel-aluminium-cobalt (NCA) LIB cells using aqueous discharging via solutions of sodium chloride (NaCl), sodium hydroxide (NaOH), and sodium nitrate (NaNO3) within the 5-30 wt. % range. Additionally, the work monitored several procedure parameters, including the voltage profiles during discharging, the extent of battery contacts and casing damage after discharging, the character and material composition of the obtained battery mass, and the composition of the wastewater obtained after separating the solid product from waste solutions. Consequently, it was determined that the industrial implementation of these procedures, including material leakage and disposal, may incur economic losses of up to 1560 USD/tonne due to metal loss.

Unlocking Insights: A Systematic Survey of Material Composition in Lithium-Ion Battery Cells for Recycling Solutions

  • DOI: 10.1109/ISSE61612.2024.10603575
  • Odkaz: https://doi.org/10.1109/ISSE61612.2024.10603575
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Battery recycling involves the recovery of materials from end-of-life (EOL) batteries, which are subsequently reused in the manufacturing of new products. Metals such as cobalt, lithium, nickel, manganese, aluminium, and copper are essential components of the electrodes of common lithium-ion batteries. In light of the growing demand for advancements in battery recycling, there is a critical need to start systematically documenting the chemistry of different types of batteries and to monitor the changes within their internal composition between the different states of charge, such as full charge, full discharge, deep discharge or shipping-state. In this work, a new methodology for a complex, quick, cheap, and effective material composition survey is presented. This methodology was applied to three types of cylindrical (18650) cells with two different cathode materials, specifically nickel cobalt aluminium (NCA) and nickel manganese cobalt (NMC), all with a capacity range from 3350 to 3500 mAh. This work offers a comprehensive, step-by-step description of the versatile battery research process, serving as the foundation for a streamlined and effective methodology for obtaining selected chemical and material parameters. The research endeavours to compare the material composition of lithium-ion cells at various states of charge to assess recycling potential and establish a database containing battery parameters. The results are essential for the automation and roboticization of the advanced recycling sector.

Variations in Open Circuit Voltage of Cycle-Aged Lithium-Ion Batteries due to Silicon-Enhanced Anodes

  • Autoři: Galasso, M., Schwunk, S., MSc. Václav Knap, Ph.D.,
  • Publikace: 2024 47th International Spring Seminar on Electronics Technology (ISSE). New York: IEEE Press, 2024. International Spring Seminar on Electronics Technology (ISSE). ISSN 2161-2536. ISBN 979-8-3503-8548-9.
  • Rok: 2024
  • DOI: 10.1109/ISSE61612.2024.10603560
  • Odkaz: https://doi.org/10.1109/ISSE61612.2024.10603560
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    We present the outcomes of cycle aging tests performed on 16 lithium-ion battery cells of different types, both commercially available: INR21700M50LT produced by LG Energy Solution and INR18650M35A produced by Molicel. These cells exhibit differences in silicon content within the anode, coupled with the utilization of two different cathode materials. Throughout the testing process, the cells underwent cycling with different state of charge (SOC) windows: 0-90%, 0-30%, 30-60% and 60-90% as well as routine checkup phases, which include a measurement of the residual capacity and of the quasi-open circuit voltage (qOCV) curve. After 260 equivalent full cycles, we found substantial differences in the aging of the two cell types, evident in both their state of health and in the variations of the qOCV curve. The LG M50LT displayed a notably slower capacity fade up to 3x less with respect to the Molicel M35A under identical testing conditions. We also found out that cycling in the SOC window 0-90% produced the least pronounced variations in the qOCV curve of the LG M50LT, while the opposite is true for the Molicel M35A. This discrepancy cannot be explained only in terms of a different silicon content, therefore the reasons have to be searched in the complex interactions between the two anode materials, as well as in cathode material degradation.

Adaptive configuration of generalized nonlinear ECM of Li-ion batteries based on impedance measurements and DRT analysis

  • Autoři: Sihvo, J., MSc. Václav Knap, Ph.D., Roinila, T., Stroe, D.-I.
  • Publikace: 2023 25th European Conference on Power Electronics and Applications (EPE'23 ECCE Europe). Sydney: IEEE, 2023. p. 1-7. ISBN 9798350316780.
  • Rok: 2023
  • DOI: 10.23919/EPE23ECCEEurope58414.2023.10264524
  • Odkaz: https://doi.org/10.23919/EPE23ECCEEurope58414.2023.10264524
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    An adaptive approach for configuration of generalized battery nonlinear equivalent-circuit-model (ECM) is proposed. In the approach, the distribution-relaxation-times (DRT) analysis is used to configure and initialize the ECM to be fitted to the impedance data. The performance of the approach is validated and analyzed by using experimental battery impedance measurements.

Assessing Lifetime, Performance, and Functionality Impact for CubeSat Battery Packs via Modelling

  • Autoři: MSc. Václav Knap, Ph.D.,
  • Publikace: 2023 13th European Space Power Conference (ESPC). Barcelona: IEEE, 2023. p. 1-5. ISBN 979-8-3503-2899-8.
  • Rok: 2023
  • DOI: 10.1109/ESPC59009.2023.10298147
  • Odkaz: https://doi.org/10.1109/ESPC59009.2023.10298147
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Batteries are an essential part of CubeSats, and their lifetime is heavily dependent on them. To accurately predict the battery lifetime, cell inhomogeneities and battery pack functionalities are needed to be considered. Thus, in this work, a model is proposed for battery performance and lifetime prediction during various missions, such as orbiting Earth or deep space. The model is based on an electrical circuit model, degradation model, and self-discharge model while allowing to apply cell-to-cell variations to each cell. The need for balancing functionality for non-identical cells was confirmed. Moreover, the influence of battery cell parameters on a battery pack's performance and lifetime was studied individually to assess their significance. The Coulombic efficiency was identified as the most critical parameter that causes SOC imbalance and consequently heterogeneous degradation. Thus, it is suggested to prioritize it when performing cell matching.

Degradation behaviour analysis and end-of-life prediction of lithium titanate oxide batteries

  • Autoři: Soltani, M., Vilsen, Soren B., Stroe, A., MSc. Václav Knap, Ph.D., Stroe, D.-I.
  • Publikace: Journal of Energy Storage. 2023, 68 1-12. ISSN 2352-152X.
  • Rok: 2023
  • DOI: 10.1016/j.est.2023.107745
  • Odkaz: https://doi.org/10.1016/j.est.2023.107745
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Lithium-ion batteries (LiBs) with Lithium titanate oxide Li4Ti5O12(LTO) negative electrodes are an alternative to graphite-based LiBs for high power applications. These cells offer a long lifetime, a wide operating temperature, and improved safety. To ensure the longevity and reliability of the LTO cells in different applications, battery health diagnosis, and lifetime prediction are crucial. This paper examines the cycling ageing behaviour of LTO cells in two different cell temperatures under high-current cycling conditions and various cycle depth (CD) tests. The ageing behaviour is investigated via capacity degradation trend using data-driven technique based on feedforward neural network (FFNN). The model is later validated with the experimental result collected in-house and the lifetime data provided by the manufacturer. The proposed method accurately determines the state of health (SOH) level and predicts the end of life (EOL) with an acceptable error of 5 %.

Investigation of the temperature and DOD effect on the performance-degradation behavior of lithium–sulfur pouch cells during calendar aging

  • Autoři: Capkova, D., MSc. Václav Knap, Ph.D., Fedorkova, A.S., Stroe, D.-I.
  • Publikace: Applied Energy. 2023, 332 1-11. ISSN 0306-2619.
  • Rok: 2023
  • DOI: 10.1016/j.apenergy.2022.120543
  • Odkaz: https://doi.org/10.1016/j.apenergy.2022.120543
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    High-energy density sulfur cathodes are one of the most promising possibilities to replace currently used intercalation cathodes in lithium-ion batteries in future applications. However, lithium–sulfur batteries are still the subject of research due to unsatisfactory capacity retention and cycle performance. The cause of insufficient properties is the shuttle effect of higher polysulfides which are formed in a high voltage plateau. In an effort to optimize storage conditions of lithium–sulfur (Li–S) batteries, long-term calendar aging tests at various temperatures and depth-of-discharge were performed on pre-commercial 3.4 Ah Li–S pouch cells. The decrease in performance over two years of calendar aging in five stationary conditions was analyzed using non-destructive electrochemical tests. The negative effect on Li–S cell performance was more pronounced for temperature than for depth-of-discharge. The analyses of self-discharge and shuttle current were performed and as expected, the highest values were measured in a fully charged state where higher polysulfides are present. Furthermore, internal resistance was analyzed where an increase of resistance was observed for a discharged state due to the formation of a passivation layer from discharge products (Li2S2, Li2S). To maximize the life of the Li–S battery, storage at high temperatures and in a fully charged state should be avoided.

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.

Activated and carbonized metal-organic frameworks for improved cycle performance of cathode material in lithium-sulphur batteries

  • Autoři: Capkova, D., Almasi, D., Macko, J., Kiraly, N., Cech, O., Cudek, P., Strakova Fedorkova, A., MSc. Václav Knap, Ph.D., Kazda, T.
  • Publikace: Journal of Physics: Conference Series. Bristol: IOP Publishing Ltd, 2022. p. 1-9. vol. 2382. ISSN 1742-6588.
  • Rok: 2022
  • DOI: 10.1088/1742-6596/2382/1/012010
  • Odkaz: https://doi.org/10.1088/1742-6596/2382/1/012010
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    The development of new battery systems has been intensively pursued in an effort to increase energy densities. Lithium-sulphur batteries represent a group of next-generation batteries with high theoretical capacity and energy density. The electrochemical properties of lithium-sulphur batteries may be improved by the application of appropriate conductive and porous additives to sulphur in the cathode material. Recently, materials belonging to the group of metal-organic frameworks (MOFs) have been widely investigated as host materials for sulphur thanks to their unique porous structure. In this work, various types of MOFs (GaTCPP, MOF-76(Gd), MIL-101(Fe)-NH2) were applied to the cathode material. MOFs were activated or carbonized before cathode material preparation. The structure of activated GaTCPP showed the lowest capacity fading per cycle (0.07 %) from activated MOFs during cycling at 0.5 C for 200 cycles. The carbonization process may improve the electrochemical properties of the electrode material. The best electrochemical properties showed carbonized MOF-76(Gd), and the capacity fading rate per cycle was only 0.04 % despite 200 cycles at 0.5 C.

Analysis of 3.4 Ah lithium-sulfur pouch cells by electrochemical impedance spectroscopy

  • Autoři: Capkova, D., MSc. Václav Knap, Ph.D., Fedorkova, A.S., Stroe, D.-I.
  • Publikace: Journal of Energy Chemistry. 2022, 72 318-325. ISSN 2095-4956.
  • Rok: 2022
  • DOI: 10.1016/j.jechem.2022.05.026
  • Odkaz: https://doi.org/10.1016/j.jechem.2022.05.026
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Despite great progress in lithium-sulfur (Li-S) batteries, the electrochemical reactions in the cell are not yet fully understood. Electrode processes, complex interfaces and internal resistance may be characterized by electrochemical impedance spectroscopy (EIS). EIS is a non-destructive technique and easy to apply, though there are challenges in ensuring the reproducibility of measurements and the interpretation of impedance data. Here, we present the impedance behavior of a 3.4 Ah Li-S pouch cell characterized by EIS. The impedance changes were analyzed over the entire depth-of-discharge, depth-of-charge, and at various temperatures. Based on the formation of intermediates during (dis)charging, the changes of resistances are observed. Overall, the increase in temperature causes a decrease in electrolyte viscosity, lowering the surface energy which can improve the penetration of the electrolyte into the electrode pores. Moreover, the effect of superimposed AC current during EIS measurement was analyzed, and the results show the dependence of the charge transfer resistance on superimposed AC current which was lower compared to steady-state conditions and consents with theory.

Battery Current and Temperature Mission Profiles for CubeSats at Low Earth Orbit

  • Autoři: MSc. Václav Knap, Ph.D., Beczkowski, S., Vestergaard, L.K., Stroe, D.
  • Publikace: IEEE Transactions on Aerospace and Electronic Systems. 2022, 58(5), 4656-4668. ISSN 0018-9251.
  • Rok: 2022
  • DOI: 10.1109/TAES.2022.3164867
  • Odkaz: https://doi.org/10.1109/TAES.2022.3164867
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    CubeSats, a branch of the space industry, has lately received great interest for being an affordable satellite platform. For proper functioning, they are nowadays practically dependent on Lithium-ion batteries as a power supply at moments, when there is not enough power generated by solar panels. Thus, batteries have to be thoroughly tested to ensure that they provide sufficient performance, lifetime and that they are safe. In other industry areas, such as electric vehicles, it is common to use mission profiles (often referred to as driving profiles) for battery testing to closely emulate conditions that are experienced in practice. However, mission profiles reflecting closely CubeSat conditions are not publicly available. Thus, this paper proposes a methodology to derive mission profiles, and resulting representative mission profiles, dedicated especially to battery testing. The proposed methodology is based on analyzed telemetry data from three GOMX CubeSats. At first, electrical current characteristics are obtained from the telemetry and are generalized across the satellites, to be subsequently used for the mission profile synthesis. The battery temperature is an important factor for the battery performance and lifetime, and it was identified to be very dynamic in CubeSats. Thus, a model describing battery temperature during their mission is proposed to enable generate realistic temperature mission profiles. Finally, the current and temperature profiles are synchronized to capture their mutual impact on the batteries, and they are formulated to be suitable for on-ground (laboratory) testing.

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.

Electrochemical Impedance Spectroscopy Processing and Modelling for Lithium-ion Batteries Using Python and Jupiter

  • Autoři: Ing. Martin Molhanec, CSc., MSc. Václav Knap, Ph.D.,
  • Publikace: 2022 45th International Spring Seminar on Electronics Technology (ISSE). New York: IEEE Press, 2022. p. 1-6. International Spring Seminar on Electronics Technology (ISSE). ISSN 2161-2536. ISBN 978-1-6654-6589-2.
  • Rok: 2022
  • DOI: 10.1109/ISSE54558.2022.9812762
  • Odkaz: https://doi.org/10.1109/ISSE54558.2022.9812762
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    This paper describes how to model a Lithium-ion battery's internal characteristics based on electrochemical impedance spectroscopy (EIS) data and their fitting into an Equivalent Circuit Model (ECM) using Python and the Jupyter development environment. The described method is used on an extensive dataset collected during an ageing campaign of lithium-ion batteries. The work aims to determine the correct values of ECM elements with satisfactory accuracy. The battery's ECM parameter interpretation provides essential information about its internal structure and mechanisms, which helps to understand its processes and estimate its future degradation. It was necessary to deal with two tasks: first, the processing of many measurements, and second, estimating the appropriate input parameters for the ECM. We have managed to practically automate the processing of more than one thousand files with measured data and design and gradually refine a method for estimating input parameters for ECM fitting.

EQUILIBRIUM THERMODYNAMIC PROPERTIES AND ITS NEW RATING FOR LITHIUM-ION BATTERY

  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Lithium battery diagnostics should comprehensively monitor battery status. To increase the level of diagnostics, it is necessary to expand with new parameters. The GITT method is used for the analysis of diffusion process. However, the method has drawbacks when applied to current electrode structures. They exhibit inconsistencies during their measurements and evaluation. Consequently, this work builts upon state-of-the-art and it proposes a new solution for determination of necessary relaxation time after a pulse to determine accurately a diffusion coefficient.

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.

Battery temperature behavior in CubeSats at low Earth orbit: From telemetry to ground testing

  • Autoři: MSc. Václav Knap, Ph.D., Vestergaard, J., Beczkowski, S., Stroe, D.-I.
  • Publikace: Proceedings of the International Astronautical Congress, IAC. Paris: International Astronautical Federation (IAF), 2021. p. 1-7. ISSN 0074-1795.
  • Rok: 2021
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    CubeSats are on a rise as an agile and perspective satellite technology. They are small satellites of a standardized format, using commercial off-the-shelf (COTS) components, which reduces their manufacturing and lunching costs. Batteries are a key part of CubeSats with the task of providing energy whenever needed. Thus, the satellite lifetime is limited (partly) by battery life. Lithium-ion batteries, the state-of-the-art choice for CubeSats, are complex electrochemical systems, with their performance and lifetime behavior strongly influenced by the temperature. Thus, the battery temperature behavior in CubeSats is the focus of this work. Aspects of thermal environment and modelling of CubeSats and batteries are reviewed. Satellite’s telemetry is used to derive a temperature data-driven model for low Earth orbit conditions. This model is then convenient for generating test and simulation profiles reflecting realistic conditions that are used throughout the remaining work. A battery management system and its algorithms are one area that must be adapted to such dynamic temperature changes. Thus, a state-of-charge estimation method was developed and demonstrated against a CubeSat temperature profile. Another important area affected by temperature is battery lifetime. A set of calendar and cycling tests were performed and assessed to evaluate a cell’s capability to support five-years long commercial missions. Finally, as means to directly influence a battery temperature, heaters are commonly used. A model is developed for evaluating the heaters’ control, which should ensure better performance and lifetime of batteries in cold cases.

Calendar Degradation and Self-Discharge Occurring During Short- and Long-Term Storage of NMC Based Lithium-Ion Batteries

  • DOI: 10.1149/10501.0003ecst
  • Odkaz: https://doi.org/10.1149/10501.0003ecst
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Idling periods are a major part of the Lithium-ion battery operation. Due to parasitic reactions, the battery capacity is decreasing and self-discharge occurs over time. Thus, in order to predict the battery lifetime and optimize its operation, it is required to capture this behavior. In this study, two different storage periods of 2 and 6 months were investigated and used to develop and validate models dedicated to reversible and irreversible capacity loss. It has been observed that while for the shorter storage period, the self-discharge rate does not change significantly, for the longer storage period it decreased during aging. Moreover, the degradation rates vary significantly for various time scales at low temperature, while at medium and high temperatures they are matching closely for 2- and 6-months periodic storage.

Effects of open-circuit voltage tests and models on state-of-charge estimation for batteries in highly variable temperature environments: Study case nano-satellites

  • Autoři: MSc. Václav Knap, Ph.D., Stroe, D.-I.
  • Publikace: Journal of Power Sources. 2021, 498 1-10. ISSN 0378-7753.
  • Rok: 2021
  • DOI: 10.1016/j.jpowsour.2021.229913
  • Odkaz: https://doi.org/10.1016/j.jpowsour.2021.229913
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Nano-satellites are a rapidly developing field of the space industry. Their structure and environmental conditions impose requirements for their functioning and reliability. One of key systems to keep nano-satellites in operation is the energy storage, often in a form of batteries, which supplies power, when there is not enough generation from solar panels. Thus, it is desirable to monitor the battery states, such as the state-of-charge (SOC). This topic was investigated in connection to other applications as electric vehicles or stationary storage; however, their working conditions are different from nano-satellites’. We propose a SOC estimation method, which takes into account these conditions, especially wide and rapidly changing temperature. The SOC is estimated through an unscented Kalman filter (UKF), which uses open-circuit voltage as pseudo-measurement, obtained from an online parameter identification method. Furthermore, to achieve a high accuracy SOC estimation, various open-circuit voltage models and characterization test procedures were evaluated. Finally, the SOC root mean square error of 0.53% was reached for a rapid temperature varying nano-satellite mission profile with thermal gradient of 22.4°C/hour by using an extended Kalman filter for online parameter identification and UKF for SOC estimation, based on the analytical OCV model characterized from quasi open-circuit voltage test.

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).

Investigation on Cycling and Calendar Aging Processes of 3.4 Ah Lithium-Sulfur Pouch Cells

  • Autoři: Gohari, S., MSc. Václav Knap, Ph.D., Yaftian, M.R.
  • Publikace: SUSTAINABILITY. 2021, 13(16), 1-13. ISSN 2071-1050.
  • Rok: 2021
  • DOI: 10.3390/su13169473
  • Odkaz: https://doi.org/10.3390/su13169473
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Much attention has been paid to rechargeable lithium-sulfur batteries (Li–SBs) due to their high theoretical specific capacity, high theoretical energy density, and affordable cost. However, their rapid c fading capacity has been one of the key defects in their commercialization. It is believed that sulfuric cathode degradation is driven mainly by passivation of the cathode surface by Li2S at discharge, polysulfide shuttle (reducing the amount of active sulfur at the cathode, passivation of anode surface), and volume changes in the sulfuric cathode. These degradation mechanisms are significant during cycling, and the polysulfide shuttle is strongly present during storage at a high state-of-charge (SOC). Thus, storage at 50% SOC is used to evaluate the effect of the remaining degradation processes on the cell’s performance. In this work, unlike most of the other previous observations that were performed at small-scale cells (coin cells), 3.4 Ah pouch Li–SBs were tested using cycling and calendar aging protocols, and their performance indicators were analyzed. As expected, the fade capacity of the cycling aging cells was greater than that of the calendar aging cells. Additionally, the measurements for the calendar aging cells indicate that, contrary to the expectation of stopping the solubility of long-chain polysulfides and not attending the shuttle effect, these phenomena occur continuously under open-circuit conditions.

Performance evaluation of lithium-ion batteries (LiFePO4 cathode) from novel perspectives using a new figure of merit, temperature distribution analysis, and cell package analysis

  • Autoři: Song, S., Munk-Nielsen, S., MSc. Václav Knap, Ph.D., Uhrenfeldt, C.
  • Publikace: Journal of Energy Storage. 2021, 44 1-11. ISSN 2352-152X.
  • Rok: 2021
  • DOI: 10.1016/j.est.2021.103413
  • Odkaz: https://doi.org/10.1016/j.est.2021.103413
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    A comprehensive performance evaluation is required to find an optimal battery for the battery energy storage system. Due to the relatively less energy density of lithium iron phosphate batteries, their performance evaluation, however, has been mainly focused on the energy density so far. In this paper, a multifaceted performance evaluation of lithium iron phosphate batteries from two suppliers was carried out. A newly proposed figure of merit, that can represent charging / discharging energy efficiency and thermal performance, is proposed. The figure of merit allows designers to conveniently select a battery with a higher round-trip efficiency and require less cooling load for the battery energy storage system. Temperature distribution characteristics, which can affect the accuracy of state prediction and lifespan, have been evaluated with a high-performance infrared camera. Even though the energy density of a certain battery is relatively lower, it has been confirmed that it could show better round-trip energy efficiency and thermal performance through the evaluations. It is revealed by structural analysis with three-dimensional X-ray computed tomography scanning that this performance difference is related to the tab design and package inside the batteries. Moreover, a temperature monitoring methodology to minimize temperature measurement errors in the battery management systems is proposed.

A Review of Battery Technology in CubeSats and Small Satellite Solutions

  • Autoři: MSc. Václav Knap, Ph.D., Vestergaard, L., Stroe, D.
  • Publikace: Energies. 2020, 13(16), 1-25. ISSN 1996-1073.
  • Rok: 2020
  • DOI: 10.3390/en13164097
  • Odkaz: https://doi.org/10.3390/en13164097
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    CubeSats and small satellite solutions are increasing in popularity as they enable a fast, cheap, and agile way for satellite applications. An essential component of nearly every satellite is the energy storage device, which is practically equal to a battery. Consequently, an overview of past, present, and future battery technologies for CubeSats is presented. CubeSats use typically commercial off-the-shelf (COTS) batteries. They are not primarily dedicated to space, so their suitability to the space environment needs to be evaluated. Batteries are also considered as potentially dangerous goods. Thus, there are guidelines and standards that specify safety criteria and tests for the batteries in order to be allowed for transportation and launch. Furthermore, the character of satellites' missions determines their demand on batteries in terms of current rates, depth-of-discharge, and lifetime. Thus, these expectations are discussed. A market survey was also carried out to identify currently available commercial battery solutions and their parameters. This work summarizes the status, requirements, and the market situation of batteries for CubeSats.

Development of a Model-Based Approach to Capture Battery Parameter Degradation in Satellites

  • Autoři: MSc. Václav Knap, Ph.D., Beczkowski, S., Stroe, D.I.
  • Publikace: ECS Transactions. New Jersey: The Electrochemical Society, 2020. p. 341-349. vol. 99. ISSN 1938-6737. ISBN 9781607685395.
  • Rok: 2020
  • DOI: 10.1149/09901.0341ecst
  • Odkaz: https://doi.org/10.1149/09901.0341ecst
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    There is an increasing number of CubeSats being launched on the Earth's orbit. They are typically based on commercial off-the-shelf batteries that are not primarily designed for space applications. Thus, their actual degradation in this environment needs to be considered, compared to on-ground laboratory conditions. In this work, a model-based method is introduced for tracking the change in battery model parameters, including the battery capacity. The method is based on collected telemetry data and it covers specific and variable battery temperature conditions in CubeSats. However, it is shown that the method is sensitive to telemetry quality, regarding sample resolution and sample loss. Thus, the used settings could not determine battery degradation trends with high confidence. Nevertheless, steps for improvement were identified that shall increase the accuracy of the results in future work.

Evaluation of the battery degradation factors for nano-satellites at LEO

  • Autoři: MSc. Václav Knap, Ph.D., Vestergaard, L., Gismero, A., Stroe, D.I.
  • Publikace: Proceedings of the International Astronautical Congress, IAC. Paris: International Astronautical Federation (IAF), 2020. p. 1-7. ISSN 0074-1795.
  • Rok: 2020
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    Mission design and spacecraft design are challenging activities, which have to be carefully conducted in order to achieve a successful mission for a nano-satellite. In NewSpace, especially in the area of nano-satellites, there is a strong drive towards agile and quickly market deployed products. Typically, commercial-off-the-shelf (COTS) batteries are used and their manufacturers rarely provides specifically needed information about them. Thus, it is necessary for the nano-satellite developer to assess the battery performance and lifetime, on their own, in order to support an accurate mission/spacecraft design. In the proposed approach, the possible degradation factors and their feasible ranges were firstly considered, in order to limit the test requirements, and the selected degradation tests were performed. The scope of battery performance indicators analysis was limited to battery capacity and resistance. Their change and sensitivity were evaluated in relation to calendar aging, considering temperature and state-of-charge factors, and to cycling aging, considering temperature and cycle depth factors, and to radiation aging. Afterwards, the identified degradation rates were used for lifetime modelling. The resulting lifetime model had 0.69% and 0.81% root-mean-square-error, compared to the experiment, for the prediction of capacity and resistance, respectively.

NÁVRH METOD PRO DIAGNOSTIKU DIFÚZNÍHO PROCESU LI-ION BATERIE

  • Autoři: Reichl, T., MSc. Václav Knap, Ph.D.,
  • Publikace: 41. NEKONVENČNÍ ZDROJE ELEKTRICKÉ ENERGIE. Praha: Česká elektrotechnická společnost, 2020. p. 96-99. ISBN 978-80-02-02900-7.
  • Rok: 2020
  • Pracoviště: Katedra elektrotechnologie
  • Anotace:
    In today's applications, batteries, in the role of electricity storage, have a significant and irreplaceable place. Lithium-ion (Li-ion) batteries have become the most popular technology. When using them, great importance is placed on safety and therefore it is necessary to monitor their condition. Since it is a complex electrochemical system and it is practically possible to measure only their electrical quantities and temperature, their diagnostics becomes a challenging task. With regard to the internal process of lithium ion diffusion, new diagnostic methods using short current pulses to detect a change in the diffusion process, which changes with the age of the battery, are presented. Two methods will be presented here, which seem to be very promising for the analysis of the diffusion process. The first results show positive conclusions.

Za stránku zodpovídá: Ing. Mgr. Radovan Suk