TY - JOUR A1 - Kleiner, Jan A1 - Komsiyska, Lidiya A1 - Elger, Gordon A1 - Endisch, Christian T1 - Thermal modelling of a prismatic lithium-ion cell in a battery electric vehicle environment BT - influences of the experimental validation setup JF - Energies N2 - In electric vehicles with lithium-ion battery systems, the temperature of the battery cells has a great impact on performance, safety, and lifetime. Therefore, developing thermal models of lithium-ion batteries to predict and investigate the temperature development and its impact is crucial. Commonly, models are validated with experimental data to ensure correct model behaviour. However, influences of experimental setups or comprehensive validation concepts are often not considered, especially for the use case of prismatic cells in a battery electric vehicle. In this work, a 3D electro–thermal model is developed and experimentally validated to predict the cell’s temperature behaviour for a single prismatic cell under battery electric vehicle (BEV) boundary conditions. One focus is on the development of a single cell’s experimental setup and the investigation of the commonly neglected influences of an experimental setup on the cell’s thermal behaviour. Furthermore, a detailed validation is performed for the laboratory BEV scenario for spatially resolved temperatures and heat generation. For validation, static and dynamic loads are considered as well as the detected experimental influences. The validated model is used to predict the temperature within the cell in the BEV application for constant current and Worldwide harmonized Light vehicles Test Procedure (WLTP) load profile. UR - https://doi.org/10.3390/en13010062 KW - Lithium-Ionen-Batterie KW - Elektrofahrzeug Y1 - 2019 UR - https://doi.org/10.3390/en13010062 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-7532 SN - 1996-1073 VL - 13 IS - 1 PB - MDPI CY - Basel ER - TY - JOUR A1 - Kotak, Bhavya A1 - Kotak, Yash A1 - Brade, Katja A1 - Kubjatko, Tibor A1 - Schweiger, Hans-Georg T1 - Battery Crush Test Procedures in Standards and Regulation: Need for Augmentation and Harmonisation JF - Batteries N2 - Battery safety is a prominent concern for the deployment of electric vehicles (EVs). The battery powering an EV contains highly energetic active materials and flammable organic electrolytes. Usually, an EV battery catches fire due to its thermal runaway, either immediately at the time of the accident or can take a while to gain enough heat to ignite the battery chemicals. There are numerous battery abuse testing standards and regulations available globally. Therefore, battery manufacturers are always in dilemma to choose the safest one. Henceforth, to find the optimal outcome of these two major issues, six standards (SAE J2464:2009, GB/T 31485-2015:2015, FreedomCAR:2006, ISO 12405-3:2014, IEC 62660-2:2010, and SAND2017-6295:2017) and two regulations (UN/ECE-R100.02:2013 and GTR 20:2018), that are followed by more than fifty countries in the world, are investigated in terms of their abuse battery testing conditions (crush test). This research proves that there is a need for (a) augmenting these standards and regulations as they do not consider real-life vehicle crash scenarios, and (b) one harmonised framework should be developed, which can be adopted worldwide. These outcomes will solve the battery manufacturers dilemma and will also increase the safety of EV consumers. UR - https://doi.org/10.3390/batteries7030063 KW - lithium-ion battery KW - electric vehicle battery KW - battery standard KW - battery regulation KW - battery testing standard KW - battery testing regulation KW - abuse testing KW - harmonising battery standard KW - crush test procedure KW - battery incidents KW - battery standard and regulation augmentation Y1 - 2021 UR - https://doi.org/10.3390/batteries7030063 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-11083 SN - 2313-0105 VL - 7 IS - 3 PB - MDPI CY - Basel ER - TY - JOUR A1 - Kugele, Stefan A1 - Obergfell, Philipp A1 - Sax, Eric T1 - Model-based resource analysis and synthesis of service-oriented automotive software architectures JF - Software and Systems Modeling N2 - Context Automotive software architectures describe distributed functionality by an interaction of software components. One drawback of today’s architectures is their strong integration into the onboard communication network based on predefined dependencies at design time. The idea is to reduce this rigid integration and technological dependencies. To this end, service-oriented architecture offers a suitable methodology since network communication is dynamically established at run-time. Aim We target to provide a methodology for analysing hardware resources and synthesising automotive service-oriented architectures based on platform-independent service models. Subsequently, we focus on transforming these models into a platform-specific architecture realisation process following AUTOSAR Adaptive. Approach For the platform-independent part, we apply the concepts of design space exploration and simulation to analyse and synthesise deployment configurations, i. e., mapping services to hardware resources at an early development stage. We refine these configurations to AUTOSAR Adaptive software architecture models representing the necessary input for a subsequent implementation process for the platform-specific part. Result We present deployment configurations that are optimal for the usage of a given set of computing resources currently under consideration for our next generation of E/E architecture. We also provide simulation results that demonstrate the ability of these configurations to meet the run time requirements. Both results helped us to decide whether a particular configuration can be implemented. As a possible software toolchain for this purpose, we finally provide a prototype. Conclusion The use of models and their analysis are proper means to get there, but the quality and speed of development must also be considered. UR - https://doi.org/10.1007/s10270-021-00896-9 KW - Service-oriented architecture KW - Real-time behaviour KW - Model-based design KW - Automotive architectures Y1 - 2021 UR - https://doi.org/10.1007/s10270-021-00896-9 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-11098 SN - 1619-1374 VL - 20 IS - 6 SP - 1945 EP - 1975 PB - Springer CY - Berlin ER - TY - JOUR A1 - Obermaier, Christina A1 - Riebl, Raphael A1 - Al-Bayatti, Ali H. A1 - Khan, Sarmadullah A1 - Facchi, Christian T1 - Measuring the Realtime Capability of Parallel-Discrete-Event-Simulations JF - Electronics N2 - Speeding up Discrete Event Simulations (DESs) is a broad research field. Promising Parallel Discrete Event Simulation (PDES) approaches with optimistic and conservative synchronisation schemes have emerged throughout the years. However, in the area of real-time simulation, PDESs are rarely considered. This is caused by the complex problem of fitting parallel executed DES models to a real-time clock. Hence, this paper gives an extensive review of existing conservative and optimistic synchronisation schemes for PDESs. It introduces a metric to compare their real-time capabilities to determine whether they can be used for soft or firm real-time simulation. Examples are given on how to apply this metric to evaluate PDESs using synthetic and real-world examples. The results of the investigation reveal that no final answer can be given if PDESs can be used for soft or firm real-time simulation as they are. However, boundary conditions were defined, which allow a use-case specific evaluation of the real-time capabilities of a certain parallel executed DES. Using this in-depth knowledge and can lead to predictability of the real-time behaviour of a simulation run. UR - https://doi.org/10.3390/electronics10060636 KW - real-time simulation KW - Vehicular Ad Hoc Networks KW - Discrete Event Simulation KW - network simulation Y1 - 2021 UR - https://doi.org/10.3390/electronics10060636 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10883 SN - 2079-9292 VL - 10 IS - 6 PB - MDPI CY - Basel ER - TY - JOUR A1 - Mehta, Kedar A1 - Ehrenwirth, Mathias A1 - Missall, Siegmund A1 - Degembaeva, Nadira A1 - Akmatov, Kuban A1 - Zörner, Wilfried T1 - Energy Profiling of a High-Altitude Kyrgyz Community: Challenges and Motivations to Preserve Floodplain Ecosystems Based on Household Survey JF - Sustainability N2 - The floodplain areas along the Naryn River in Kyrgyzstan are essential as they hold the riparian (local) ecosystems because they provide firewood, pastureland, and areas for recreation and protection against erosion. Due to limited access to adequate, reliable, and sustainable energy services, the rural population usually derived their energy needs from multiple natural energy resources (i.e., firewood, charcoal, agricultural residues, animal dung, and wood branches). This is considered a common and predominant practice in rural Kyrgyzstan. This situation leads to a negative impact on local ecosystem services. In addition to that, the reliance on solid fuels contributes to indoor and outdoor air pollution, which is partially threatening the local ecosystem services. By contrast, the employment of renewable-based energy supply systems would substantially reduce the burden on the environment, which is mainly untapped. To integrate renewable energies, it is important to understand the energy behavior of floodplain communities. In that response, the presented article is the first attempt to capture the energy identity of the floodplain community of Kyrgyzstan based on a quantitative energy-based (on-site) household survey. Furthermore, the present research article synthesizes the driving factors that have a (direct or indirect) impact on the energy and local ecosystem services. In addition, the present article proposes a brief pathway for the sustainable energy transition. The article records the recommendation to integrate renewable energies to preserve the local ecosystems of Kyrgyzstan. UR - https://doi.org/10.3390/su132313086 KW - Central Asia KW - ecosystem services KW - energy pattern KW - energy profiling KW - floodplain community KW - high-altitude KW - household survey KW - Kyrgyzstan KW - renewable energies KW - sustainability Y1 - 2021 UR - https://doi.org/10.3390/su132313086 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10895 SN - 2071-1050 N1 - This article belongs to the Special Issue "Floodplain Ecology and Sustainable Restoration with Regard to Ecosystem Services" VL - 13 IS - 23 PB - MDPI CY - Basel ER - TY - JOUR A1 - Mehta, Kedar A1 - Ehrenwirth, Mathias A1 - Trinkl, Christoph A1 - Zörner, Wilfried A1 - Greenough, Richard T1 - The energy situation in Central Asia BT - a comprehensive energy review focusing on rural areas JF - Energies N2 - The northern part of the globe is dominated by industrialisation and is well-developed. For many years, the southern part of the world (South Asia, Africa etc.) has been a target of research concentrating on access to energy (mainly electricity) in rural regions. However, the Central Asian region has not been a focus of energy research compared to South East Asia and Africa. Despite plentiful domestically available energy resources, the energy supply in Central Asia is very unevenly distributed between urban and rural areas. Almost half of the total population of Central Asia lives in rural areas and there is a lack of access to modern energy services to meet primary needs. To analyse the energy situation (i.e., electricity, heating, hot water consumption, cooking, etc.) in rural Central Asia, this paper reviews residential energy consumption trends in rural Central Asian regions as compared to urban areas. Furthermore, the paper illustrates the potential of renewable energies in Central Asia. To perform the study, a qualitative comparative analysis was conducted based on a literature review, data, and statistical information. In summary, the presented article discusses the rural energy situation analytically and provides in-depth insights of Central Asian energy infrastructure. UR - https://doi.org/10.3390/en14102805 KW - Central Asia KW - energy resources KW - rural energy supply KW - energy services KW - renewable energy Y1 - 2021 UR - https://doi.org/10.3390/en14102805 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10908 SN - 1996-1073 VL - 14 IS - 10 PB - MDPI CY - Basel ER - TY - JOUR A1 - Sánchez Morales, Eduardo A1 - Dauth, Julian A1 - Huber, Bertold A1 - García Higuera, Andrés A1 - Botsch, Michael T1 - High precision outdoor and indoor reference state estimation for testing autonomous vehicles JF - Sensors N2 - A current trend in automotive research is autonomous driving. For the proper testing and validation of automated driving functions a reference vehicle state is required. Global Navigation Satellite Systems (GNSS) are useful in the automation of the vehicles because of their practicality and accuracy. However, there are situations where the satellite signal is absent or unusable. This research work presents a methodology that addresses those situations, thus largely reducing the dependency of Inertial Navigation Systems (INSs) on the SatNav. The proposed methodology includes (1) a standstill recognition based on machine learning, (2) a detailed mathematical description of the horizontation of inertial measurements, (3) sensor fusion by means of statistical filtering, (4) an outlier detection for correction data, (5) a drift detector, and (6) a novel LiDAR-based Positioning Method (LbPM) for indoor navigation. The robustness and accuracy of the methodology are validated with a state-of-the-art INS with Real-Time Kinematic (RTK) correction data. The results obtained show a great improvement in the accuracy of vehicle state estimation under adverse driving conditions, such as when the correction data is corrupted, when there are extended periods with no correction data and in the case of drifting. The proposed LbPM method achieves an accuracy closely resembling that of a system with RTK. UR - https://doi.org/10.3390/s21041131 KW - machine learning KW - autonomous vehicles KW - Inertial Navigation System KW - Satellite Navigation KW - Real-Time Kinematic KW - indoor navigation KW - reference state Y1 - 2021 UR - https://doi.org/10.3390/s21041131 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10932 SN - 1424-8220 N1 - "This paper is an extended version of our paper published in : Sánchez Morales, E.; Botsch, M.; Huber, B.; García Higuera, A. High precision indoor positioning by means of LiDAR. In Proceedings of the 2019 DGON Inertial Sensors and Systems (ISS), Braunschweig, Germany, 10–11 September 2019." VL - 21 IS - 4 PB - MDPI CY - Basel ER - TY - JOUR A1 - Vannahme, Anna A1 - Ehrenwirth, Mathias A1 - Schrag, Tobias T1 - Enhancement of a district heating substation as part of a low-investment optimization strategy for district heating systems JF - Resources N2 - In an ongoing project, low-investment measures for the optimization of district heating systems are analyzed. The optimization strategies are collected in a catalog, which is the core of a guideline. The application of this guideline is demonstrated using two concrete district heating networks as examples. In this study, the improvement of an analog controlled district heating substation by an electronic controller is investigated. High supply temperatures and heat losses are often a challenge in district heating networks. The district heating substations have a major influence on the network return temperatures. The comparison of the two substation setups with analog and electronic controllers is carried out by laboratory measurement. It can be shown that the return temperatures can be reduced by an average of 20 K in winter and transition, as well as 16 K in summer. The district heating network losses are calculated for one of both specific district heating networks. They are calculated from the ratio of network losses to generated energy. The generated energy is the sum of network losses and consumer demand. The thermal losses of the network can be reduced by 3%. The volume flow in the heating network can be reduced to a quarter. Therefore, the pumping energy requirement drops sharply since these changes cubically affect the volume flow UR - https://doi.org/10.3390/resources10050053 KW - district heating substation KW - control KW - optimization KW - local district heating networks KW - non-retrofitted single-family houses KW - thermal test rig Y1 - 2021 UR - https://doi.org/10.3390/resources10050053 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10951 SN - 2079-9276 VL - 10 IS - 5 PB - MDPI CY - Basel ER - TY - JOUR A1 - Komsiyska, Lidiya A1 - Buchberger, Tobias A1 - Diehl, Simon A1 - Ehrensberger, Moritz A1 - Hanzl, Christian A1 - Hartmann, Christoph A1 - Hölzle, Markus A1 - Kleiner, Jan A1 - Lewerenz, Meinert A1 - Liebhart, Bernhard A1 - Schmid, Michael A1 - Schneider, Dominik A1 - Speer, Sascha A1 - Stöttner, Julia A1 - Terbrack, Christoph A1 - Hinterberger, Michael A1 - Endisch, Christian T1 - Critical review of intelligent battery systems BT - challenges, implementation, and potential for electric vehicles JF - Energies N2 - This review provides an overview of new strategies to address the current challenges of automotive battery systems: Intelligent Battery Systems. They have the potential to make battery systems more performant and future-proof for coming generations of electric vehicles. The essential features of Intelligent Battery Systems are the accurate and robust determination of cell individual states and the ability to control the current of each cell by reconfiguration. They enable high-level functions like fault diagnostics, multi-objective balancing strategies, multilevel inverters, and hybrid energy storage systems. State of the art and recent advances in these topics are compiled and critically discussed in this article. A comprising, critical discussion of the implementation aspects of Intelligent Battery Systems complements the review. We touch on sensing, battery topologies and management, switching elements, communication architecture, and impact on the single-cell. This review contributes to transferring the best technologies from research to product development. UR - https://doi.org/10.3390/en14185989 KW - smart battery KW - intelligent battery system KW - advanced monitoring KW - reconfigurable battery KW - battery management system KW - electric vehicle Y1 - 2021 UR - https://doi.org/10.3390/en14185989 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10132 SN - 1996-1073 VL - 14 IS - 18 PB - MDPI CY - Basel ER - TY - JOUR A1 - Ahlberg Tidblad, Annika A1 - Edström, Kristina A1 - Hernández, Guiomar A1 - de Meatza, Iratxe A1 - Landa-Medrano, Imanol A1 - Jacas Biendicho, Jordi A1 - Trilla, Lluís A1 - Buysse, Maarten A1 - Ierides, Marcos A1 - Perez Horno, Beatriz A1 - Kotak, Yash A1 - Schweiger, Hans-Georg A1 - Koch, Daniel A1 - Kotak, Bhavya T1 - Future Material Developments for Electric Vehicle Battery Cells Answering Growing Demands from an End-User Perspective JF - Energies N2 - Nowadays, batteries for electric vehicles are expected to have a high energy density, allow fast charging and maintain long cycle life, while providing affordable traction, and complying with stringent safety and environmental standards. Extensive research on novel materials at cell level is hence needed for the continuous improvement of the batteries coupled towards achieving these requirements. This article firstly delves into future developments in electric vehicles from a technology perspective, and the perspective of changing end-user demands. After these end-user needs are defined, their translation into future battery requirements is described. A detailed review of expected material developments follows, to address these dynamic and changing needs. Developments on anodes, cathodes, electrolyte and cell level will be discussed. Finally, a special section will discuss the safety aspects with these increasing end-user demands and how to overcome these issues. UR - https://doi.org/10.3390/en14144223 KW - electric vehicle KW - battery material KW - anode KW - cathode KW - electrolyte KW - battery safety KW - end-user demands Y1 - 2021 UR - https://doi.org/10.3390/en14144223 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-10149 SN - 1996-1073 VL - 14 IS - 14 PB - MDPI CY - Basel ER -