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The battery packs are crucial components of electric vehicles and may severely affect the continue voyage course and vehicle safety. Therefore, design optimization of the battery-pack enclosure (BPE) is critical for enhanced mechanical and crashwrothiness performances. In this study, a lightweight design of an automotive BPE under the loading conditions is presented based on the advanced high-strength steels (AHSSs) and size optimization. A numerical analysis procedure is also introduced for the lightweight design. First of all, a nonlinear finite element (FE) BPE model was established and validated through the modal test. Secondly, the random vibration simulation was performed based on the sensitivity analysis to initially determine the AHSSs and thickness for the components of the BPE. Next, the material and thickness were determined by the fixed-frequency vibration analysis. Moreover, the mechanical shock and fatigue life were analyzed numerically. Finally, the crashworthiness of the optimized BPE model was verified by crash and crush simulations. The results show that the optimized BPE structure has a 10.41 % lightweight gain, while assuring enhanced dynamic performances. The introduced numerical procedure could be used to quickly determine the material and thickness of each component of BPE. The design optimization process was found beneficial to reduce the number of physical tests and product development cost and shorten product development cycles.

Conventional automotive battery systems consisting of a large number of battery cells pose a variety of challenges in terms of safety, reliability, lifetime, and energy efficiency. Reconfigurable battery systems (RBSs) are a promising solution to these issues of conventional battery systems. However, the large number of components in RBS also increases the fault probability. To meet this challenge on the way to fault tolerance, this article addresses fault isolation in an RBS, which comprises two switches per cell. Based on an electrothermal model, a structural analysis is performed and a sensor set with optimal fault isolation properties is found. Since the system consists of many equations, a novel algorithm is introduced to efficiently calculate minimal structurally overdetermined (MSO) subsystems for fault diagnosis. For each fault, the algorithm allows determining the MSO set that has the least number of equations. A complexity analysis of the algorithm reveals that the proposed algorithm is computationally significantly less expensive for systems with high redundancy, such as RBS, than existing algorithms that compute all MSO sets. Since the algorithm considers the switch states, it is suitable for active fault isolation through switches. The application to the RBS shows that the electrical equations are prioritized over the thermal equations due to the model uncertainties. A video file demonstrating the proposed graph-based algorithm with an example is attached to this article.

Submitted by Jonathan Sousa de Almeida (jonathan.sousa@ufma.br) on 2022-12-12T11:23:16Z No. of bitstreams: 1 VANESSALEITEDASILVA.pdf: 2888685 bytes, checksum: b0f748f13f8241287cc36eb295c67745 (MD5) Made available in DSpace on 2022-12-12T11:23:16Z (GMT). No. of bitstreams: 1 VANESSALEITEDASILVA.pdf: 2888685 bytes, checksum: b0f748f13f8241287cc36eb295c67745 (MD5) Previous issue date: 2022-07-29 Environmental protection requires a large diversity of social actions addressed to decrease the problems caused directly and indirectly by production, circulation, and consumption activities, conspicuously those that generate a risk of contamination of natural resources appropriated by society. This is an exploratory, descriptive, and interdisciplinary field research with a qualitative approach on the reverse logistics of vehicular batteries in São Luís. This research aims to know the practice of the reverse flow of automotive batteries in São Luís - Maranhão, through the perception of the socio-environmental and economic bias. The methodology adopted involves the data collection and analysis of information obtained from secondary and primary sources as publications, obtained by field research and application of semi-structured interviews with professionals from stores, junkyards, and vehicle owners regard to the tasks collection, reuse, and sale of automotive batteries. Due to the social distancing caused by COVID-19, some interviews were performed by phone or videoconference. The relevance of the research is based on the little importance attributed to the studies of this sustainable commercial practice and the possibility of developing new lines of investigation that can sensitize society to this theme, additionally the possibility of contributing to the scientific framework on the subject and establish bases for future studies aiming to improve the environmental quality and people's lives. The motivational factors that support this commercial practice are discussed, besides the perception of traders, vehicle owners, and manufacturers in this dynamic market for the commercialization of vehicular batteries, as well as the steps and particularities present in the reverse flow of use of these batteries. It was found that the specific legislation for disposal of solid waste, has a strong influence on the frequency and the way in which the reverse logistics of vehicular batteries occurs in the commercial region of São Luís. A proteção do ambiente requer grande diversidade de ações orientadas para a mitigação dos problemas causados, direta e indiretamente, pelas atividades de produção, circulação e de consumo, notadamente as que geram risco de contaminação dos recursos apropriados pelo homem. Esse estudo aborda uma pesquisa de campo sobre a logística reversa de baterias veiculares em São Luís e objetiva conhecer a prática do fluxo reverso de baterias, pela percepção do viés socioambiental e econômico. A metodologia adotada compreende a coleta e análise de dados e de informações obtidos em publicações, obtidas também através de pesquisa de campo e aplicação de entrevistas semiestruturadas com os profissionais de lojas e de sucatas e proprietários de veículos concernente às tarefas de recolhimento, reaproveitamento e comercialização das baterias automotivas. Devido ao isolamento social causado pelo novo coronavírus, algumas entrevistas foram realizadas por telefone ou videoconferência. A relevância da pesquisa fundamenta-se na pouca importância atribuída aos estudos dessa prática comercial e pela possibilidade de desenvolvimento de novas linhas de investigação que possam sensibilizar a sociedade para essa temática, assim como contribuir com o arcabouço científico sobre o assunto e estabelecer bases para estudos futuros com vistas a melhoraria da qualidade ambiental e da vida das pessoas. Discute-se os fatores motivacionais que sustentam essa prática comercial na região, assim como a percepção dos comerciantes, proprietários de veículos e fabricantes perante esse mercado dinâmico de comercialização de baterias veiculares, assim como as etapas e particularidades presentes no fluxo reverso de utilização dessas baterias. Verificou- se que a legislação direcionada ao descarte de resíduos sólidos, detém forte influência sob a frequência e a forma como ocorre a logística reversa de baterias veiculares na região comercial de São Luís.

The battery is a storage unit which consists of many cells, is used to produce power by undergoing some chemical process so that chemical energy is produced, and converted into electric energy, that is used as a source of power in vehicles. In conventional Engine vehicles, the batteries are used only to power the components like starter motor, horn and so on. Thus, the rate of battery discharging is slow. But today, the world is moving towards the production and use of Electric Vehicles (EV’s), in which batteries are the primary source of power. This demands for batteries with larger capacity for EV’s. Even though high-power capacity batteries are used, they tend to discharge at a much faster rate and demands charging every day. To charge these batteries, there must be very high-power input and also the charging time is more (3 to 4 h for full charge). Due to this disadvantage, people do not prefer EV’s. Thus, the concept is to introduce a system which can charge the battery when the vehicle is in motion i.e., without stopping the vehicle for charging. To enable this, the most renewable source of energy is being utilized which is Wind Energy. To harness this wind energy, the Vertical Axis Wind Turbine (VAWT) is used. The VAWT will be placed inside the front grille of the vehicle where there will be air flow, which will propel the turbine, and thus power is generated. This system is capable of reducing the time and money spent for battery charging in the EV’s.

States estimation of lithium-ion batteries is an essential element of Battery Management Systems (BMS) to meet the safety and performance requirements of electric and hybrid vehicles. Accurate estimations of the battery’s State of Charge (SoC), State of Health (SoH), and State of Power (SoP) are essential for safe and effective operation of the vehicle. They need to remain accurate despite the changing characteristics of the battery as it ages. This paper proposes an online adaptive strategy for high accuracy estimation of SoC, SoH and SoP to be implemented onboard of a BMS. A third-order equivalent circuit model structure is considered with its state vector augmented with two more variables for estimation including the internal resistance and SoC bias. An Interacting Multiple Model (IMM) strategy with a Smooth Variable Structure Filter (SVSF) is then employed to determine the SoC, internal resistance, and SoC bias of a battery. The IMM strategy results in the generation of a mode probability that is related to battery aging. This mode probability is then combined with an estimation of the battery’s internal resistance to determine the SoH. The estimated internal resistance and the SoC are then used to determine the battery SoP which provides a complete estimation of the battery states of operation and condition. The efficacy of the proposed condition-monitoring strategy is tested and validated using experimental data obtained from accelerated aging tests conducted on Lithium Polymer automotive battery cells.

A Screw Jack is used to lift a heavy load. This jack is modified and made in such a way that it can be fitted to the frame of the vehicle. Hence when the jack operates, the car can be lifted up. The jack operation is made possible with the buttons fitted to the dashboard of the vehicle. In case of puncture or any other service, there is no need for external jack. The system is user-friendly such as in case of the power window. The rocker switch is used to enable the reverse operation of the jack too. The jack is operated by an electric motor powered by the car battery. The Rocker switches are placed inside a lock protected box, in order to prevent any accidents. The rocker switch can be accessed only when it is needed.

Purpose. The purpose of this article is to design hardware for an automated system for measuring the parameters of the car battery and the subsequent approximation of its capacity and other parameters necessary to determine its condition. Originality. The paper deals with the research on the car batteries and measuring instruments to detect their parameters in order to determine a suitable software solution for automated measuring system to measure the car battery capacity. Methodology. The paper proposes one of the possibilities for development an automated system for measuring car battery capacity basing on microcontrollers system using prototyping, designing, simulation and testing techniques. Authors described the whole development process starting from computer design of the proposed device, chose the elements for hardware unit, prototyping using development boards and tools, developing program algorithms and implementing related applied software with the final results verification. Result. In this work authors proposed hardware solution of an automated system for measuring the capacity of a car battery. The whole design concept consisted of the selection of the main hardware components, which were then implemented into a complex functional unit. Following it was designed a software solution. This proposal was initiated by a program for measuring the parameters of the battery, then the calculation of the internal resistance from the measured parameters and the approximation of capacity on the basis of the detected life-span was added to this programme. A Web page was then created. Practical value. Proposed experimental sample could be practically used for automatic measurement of car battery capacity and also could be served as an experimental sample of remote measuring device. References 14, figures 14.

The undesirable stresses and deformations during a high-speed crash can cause a short circuit or sudden fire in the battery packs, which represents a significant safety concern for vehicles. In thi...

Self-heating is of extreme importance for improving the available capacity and lifetime of lithium-ion batteries in cold climates. However, few attempts have been done to achieve effective onboard self-heating for the batteries in electric vehicles. This paper derives a high-frequency sine-wave (SW) heater based on resonant LC converters to self-heat the automotive batteries at low-temperatures without the need of external heaters. To be specific, an interleaved-parallel topology is introduced to double the heating speed without extra damages to batteries compared to the single heater. Further, a corresponding thermoelectric model is developed to provide guidance for the optimal design of the parameters in the proposed SW heater. Experimental results show that with a high-frequency sinusoidal current motivated by the proposed heater, lithium-ion batteries could be effectively self-heated by the ohmic-loss and electrochemical heat. Moreover, the heating time could be significantly shortened through decreasing the characteristic impedance $\sqrt {\boldsymbol{L}/\boldsymbol{C}} $ or increasing the ac-heating frequency.

In Low-to-Middle-Income Countries more than 95% of the medical equipment are devices donated by NGOs, usually second hand, refurbished devices from High Income Country Hospitals. However, the lack of consumables and spare parts and infrastructural limitations lead to 70% of that equipment not working, or working improperly shortly after being received. The surgical suction pump at Masanga Hospital is such an example. The use of the suction pump is hindered by: • Lack of consumables and appropriate tubing, leading to a mismatch between the different components • Frequent power shortages Therefore, the goals defined for the project together with the client were to • Solve the dimensional mismatch between the medical consumables and • power the device independently from the Hospital’s solar grid by leveraging locally available resources and manufacturing opportunities. Discover, Define, Freeze The project was started with a profound analysis of the principles of suction at a HIC hospital, followed by the use and function of suction at Masanga, to better understand the current challenge and Masanga and the envisioned use of the suction pump that the design solutions should achieve. The research on suction was followed by an extensive contextual analysis. where the gathered insights helped understand the factors that influence the current situation, as well as limitations and opportunities were The findings were transformed into a List of Requirements and principal design solutions. Executive Summary Develop Various iterations, more than 50 prototypes and an extensive testing protocol were made to achieve the following goals: • To locally 3D print reusable medical tubing connectors, independently from Masanga’s current supply chain and • To make a conceptual plan for building a portable power-pack based on a 12V car battery as the power source to power the suction pump during power shortages Final Deliverables • A tested method of 3D printing reusable medical tubing connectors using PETG filament The connectors were developed through 1. Embodiment Design, 2. Design for Manufacturing and 3. Material choice. The final concept was validated on a TRL level 6. • A detailed concept plan for building a portable power- pack based on a 12V car battery with locally sourced components Conclusion The final validation phase and usability testing showed that the proposed solutions would improve the use of the suction pump, while promoting local manufacturing of spare parts and using common locally popular solutions. Both design solutions however still need to undergo testing in the context before applying them.

ICs designed for automotive applications should withstand accidental reverse polarity caused by misconnection of their supply lines to the car battery. The reverse protection circuitry should avoid damages to both the IC and the system the IC is connected to. In particular, a large power dissipation while in reverse polarity situation is to be avoided. A simple solution is to insert diodes between the supply lines and the IC supply pins but this cannot be applied to linear low dropout regulators (LDOs)This paper presents two reverse polarity protection solutions for LDOs with NMOS power transistors. Starting from a circuit based on bipolar transistors, the proposed solutions can be implemented in low-cost CMOS processes. One of them also requires far less die-area Simulation results presented in the paper validate both proposals.

Laser welding has been increasingly adopted into the automotive sector due to its competitive processing speed, less restrictive single-sided access requirements and improved process flexibility. These benefits notwithstanding, laser welding still remains susceptible to the weld cracking especially for 6xxx high strength aluminium extrusions, which are widely used in the automotive industry for body-in-white and battery tray manufacturing. This paper reviews current challenges and opportunities for construction of battery tray using aluminium alloys with laser welding process. It aims to provide a view on the selection of welding equipment in terms of beam oscillation, power modulation, beam shaping, filler wire and shielding gas, and analyze their impact on joint integrity for 6xxx grades aluminium extrusions. The driving idea is to control the thermal history in and around the molten pool and to modify the chemical composition in the fusion zone to reduce the formation of solidification cracks. Results of the study have shown that the modification of chemical composition by the use of filler wire is currently the most efficient approach to improve joint strength. Further results evidences also showed that beam shaping with adjustable ring mode laser helps to stabilize the keyhole and achieve a wider molten pool and weld interface width. Manufacturing implications are reviewed and discussed throughout the paper.

In this paper, we study the design of a free floating car sharing system based on electric vehicles. We rely on data about millions of rentals of a free floating car sharing operator based on internal combustion engine cars that we recorded in four cities. We characterize the nature of rentals, highlighting the non-stationary, and highly dynamic nature of usage patterns. Building on this data, we develop a discrete-event trace-driven simulator to study the usage of a hypothetical electric car sharing system. We use it to study the charging station placement problem, modeling different return policies, car battery charge and discharge due to trips, and the stochastic behavior of customers for plugging a car to a pole. Our data-driven approach helps car sharing providers to gauge the impact of different design solutions. Our simulations show that it is preferred to place charging stations within popular parking areas where cars are parked for short time (e.g., downtown). By smartly placing charging stations in just 8% of city zones, no trip ends with a discharged battery, i.e., all trips are feasible. Customers shall collaborate by bringing the car to a charging station when the battery level goes below a minimum threshold. This may reroute the customer to a different destination zone than the desired one; however, this happens in less than 10% of all trips.

One-way electric carsharing systems provide an environmentally friendly option for facilitating urban mobility needs. However, the management of one-way electric carsharing systems presents operational challenges stemming from the need to relocate cars in order to strike an optimum balance between demand and supply. As a result, the cost associated with vehicle relocation operations represents a significant proportion of the total operating cost. In the context of electric carsharing systems, the problem of vehicle relocation is further exacerbated by the car battery charging requirements. The introduction of temporal and spatial flexibility regarding the pick-up and drop-off of vehicles provides the means of improving the efficiency of one-way electric carsharing systems. However, the literature currently lacks models that can be used to investigate the effect of temporal and spatial flexibility on the performance of one-way electric carsharing systems. In this paper, we are introducing an integrated modeling and solution framework for investigating the effect of temporal and/or spatial flexibility, and different options for processing trip requests to the profitability and utilization of one-way electric carsharing systems. The application of the proposed framework to a realistic size system suggests that spatial flexibility has a stronger effect on the system performance than temporal flexibility. Furthermore, both spatial and temporal flexibility can increase the profitability of the system by serving more customers with fewer vehicle relocation needs.

Generators of hot gases (GHG) are used for thermal preparation of vehicles in cold climatic conditions. Their wide use is caused by the high thermal power and safety of application. The heat released in burning zone is used partly for heating air flow, partly for heating of GHG parts: guide nozzle and the false pallet. The generator of hot gases consumes from 70 to 150 W of the car battery power. In the process of thermal preparation, this leads to a decrease in the battery capacity, and as a result - the impossibility of starting the motor of the vehicle. The issue of reducing the energy consumption of the GHG, without changing its consumer qualities, becomes urgent.Keywords: thermal preparation, generator of hot gases, guide nozzle, thermoelectric generator, losses of thermal energy, the temperature field, fillersJEL Classifications: O13, Q40DOI: https://doi.org/10.32479/ijeep.8503

Determination of the high potential of dust emission is a requisite affair in the management of dusts emission and as well as avoiding its risks. Wind tunnel is among the most important approaches in the study of areas having high potential in emitting dusts. Extensive dried playas and desert areas require the making of low-cost, simple, and car-portable tunnels capable of presenting comparable data of various areas even supposing not having enough precision in the model of real wind motion. In this study, we first engaged in making a car-portable tunnel with a primarily semicircle section of 38 cm height, 50 cm diameter, and 110 cm length. A fan and key appliance with the ability to change speed were used along with a simple transformer launched with car battery. Then, concentration of the pm10 dusts was measured in the various wind speeds of 1, 2.5, 4, 5.5, and 7 m/s by the help of anemometer and digital equipments. The study of Bakhtegan playa was done, as the methodology of handling with this tunnel, in 35 positions, and zoning of the results was performed via ArcGIS software. Depending on the destructibility of the shell by wind, the areas under study were categorized as low potential (34%), medium potential (37%), and high potential (29%) in emitting dusts. The results of zoning spotted the high-potential areas on the map. The usage of small tunnels, as in the present model, may be applied in order for the low-cost and fast studies of vast areas to the purpose of playas management.

For the design of automotive battery systems, cell selection is a mandatory first step. Since lithium-ion cells bear the disadvantage of a progressive degradation process during utilization, aging characterization enables the quantification of the related phenomena. In order to achieve low development costs and due to the long-term character of cell aging, aging characterization must be conducted in an accelerated manner. This work proposes a new method for this purpose of application that is able to reproduce realistic automotive cell aging in a short time and simultaneously to guarantee consistency in the involved aging mechanisms. This method therefore combines state of the art test approaches with viable and previously unused test and evaluation concepts. As concept paper, this publication focuses on the development procedure for this new method. Summaries of results regarding identified acceleration potentials for aging characterization are also presented.

There are many degrees of freedom in the design of a battery concept for electric vehicles. A suitable lithium-ion battery (LIB) must be selected from different cell chemistries, types and sizes. During operation, the LIBs must always be kept in the optimum temperature range, thus a suitable battery thermal management system (BTMS) architecture must be developed. All these decisions have a direct impact on the later characteristics of the battery system and are subject to complex interactions. Therefore, the question arises of an automated method that supports the user in finding the ideal overall battery concept for a given vehicle concept. This paper introduces and discusses such a process. After an analysis of all relevant electrical and thermal influences and previous work on this topic, an approach is derived that allows automatic cell selection, modularization and BTMS development considering all relevant influences up to the vehicle level. The approach considers the electrical and thermal behavior on both the cell and the system level. Furthermore, the BTMS is simulated using a novel approach allowing the configuration of air and liquid cooling with any desired configuration. The complete simulation framework is made available under an open-source license.

Paper discussed the problem of influence value load current on the starting efficiency of the car batteries. Author defines concept two new types of starting efficiency of the car batteries.

Electrification of passenger cars is one of the most effective approach to reduce noxious emissions in urban areas and, if the electricity is produced using renewable sources, to mitigate the global warming. Automotive battery packages are complex systems that have to comply with many constraints: high performances in terms of gravimetric and volumetric energy and power densities, long cycle and calendar lives, electrical safety, crashworthiness, recyclability. To respect all the above requirements, battery systems integrate a complex battery management system (BMS) connected to an extended network of sensors able to measure the electric potential and the temperature at multiple points in the battery package. New sensing technologies, based on different measurement principles, are emerging as promising approaches to improve the performances of the battery systems and to respond to the needs of the automotive manufacturers.

The aim of this study was to design a tooling system for manufacturing automotive components using a natural fiber polymer composite (NFPC) material. As a case study, an automotive battery cover was selected and a compression molding tool was designed, keeping in mind the need for the simplicity of the tool and ensuring the low cost of this process. However, since the original part was injection-molded with virgin polypropene, some vital changes made in the part and tool design process were documented as a guideline to show new designers how to approach the design of parts and tools using a natural fiber polymer composite material. Additionally, the challenges faced during the manufacturing of composite parts with the new tool were also documented and solutions to these challenges were suggested for large-scale production. Finally, compressive testing was performed to evaluate the performance of the structure of the designed part and to compare the recycled polymer with NFPC material. Both wood and palm fiber composite material perform better in compression testing compared to the recycled polymer material.

Laser micro-welding is increasingly being used to produce electrically conductive joints within a battery module of an automotive battery pack. To understand the joint strength of these laser welds at an early design stage, micro-joints are required to be modelled. Additionally, structural modelling of the battery module along with the electrical interconnects is important for understanding the crash safety of electric vehicles. Fusion zone based micro-modelling of laser welding is not a suitable approach for structural modelling due to the computational inefficiency and the difficulty of integrating with the module model. Instead, a macro-model which computationally efficient and easy to integrate with the structural model can be useful to replicate the behaviour of the laser weld. A macro-modelling approach was adopted in this paper to model the mechanical behaviour of laser micro-weld. The simulations were based on 5 mm diameter circular laser weld and developed from the experimental data for both the lap shear and T-peel tests. This modelling approach was extended to obtain the joint strengths for 3 mm diameter circular seams, 5 mm and 10 mm linear seams. The predicted load–displacement curves showed a close agreement with the test data. View Full-Text\ud

Battery simulations are an essential tool for the efficient development of electric powertrains, which require accurate models and reliable hardware. Surprisingly, today’s massively collected measurements are not yet used for realistic and virtual development environments. Among other reasons, handling the large and heterogeneous datasets of automotive batteries still prevents a consequent application. Hence, a data-enhanced electric model of the battery is presented, which relies on a recurrent neural network to compensate the error of a physically-motivated model. Such a hybrid model introduces the high accuracy of machine learning to simulations. Ultimately, it allows a replacement of real batteries with model-based simulators at test benches. The approach is validated based on a comparison of a real battery with a simulator and its different model variants. It is shown, that the data-driven enhancement of existing simulations increases the accuracy while maintaining the robustness of the original model.

For the validation of safety-critical systems regarding safety and comfort, e.g., in the context of automated driving, engineers often have to cope with large (parametric) test spaces for which it is infeasible to test through all possible parameter configurations. At the same time, critical behavior of a well-engineered system with respect to prescribed safety and comfort requirements tends to be extremely rare, speaking of probabilities of order $10^{-6}$ or less, but clearly has to be examined carefully for valid argumentation. Hence, common approaches such as boundary value analysis are insufficient while methods based on random sampling from the parameter space (simple Monte Carlo) lack the ability to detect these rare critical events efficiently, i.e., with appropriate simulation budget. For this reason, a more sophisticated simulation-based approach is proposed which employs optimistic optimization on an objective function called "criticality" in order to identify effectively the set of critical parameter configurations. Within the scope of the ITEA 3 TESTOMAT project (http://www.testomatproject.eu/) the collaboration partners OFFIS e.V. and AKKA Germany GmbH conducted a case study on applying criticality-based rare event simulation to the charging process of an automotive battery management system given as a model. The present technical report documents the industrial use case, the approach, application and experimental results, as well as lessons learned from the case study., A more cohensive version of this technical report has been presented at the MSCPES 2021 workshop and will be published by ACM, available at https://doi.org/10.1145/3470481.3472701

Automotive high-voltage busbars are critical electrical components in electric vehicle battery systems as they connect individual battery modules and form the connection to the vehicle&rsquo, s powertrain. Therefore, a vehicle crash can pose a significant risk to safety by compromising busbar insulation, leading to electrical short circuits inside the battery. In turn, these can trigger thermal chain reactions in the cell modules of the battery pack. In order to ensure a safe design in future applications of busbars, this study investigated the mechanical behavior of busbars and their insulation. Our results indicated that crashlike compressive and bending loads lead to complex stress states resulting in failure of busbar insulation. To estimate the safety of busbars in the early development process using finite element simulations, suitable material models were evaluated. Failure of the insulation was included in the simulation using an optimized generalized incremental stress state dependent model (GISSMO). It was shown that sophisticated polymer models do not significantly improve the simulation quality. Finally, on the basis of the experimental and numerical results, we outline some putative approaches for increasing the safety of high-voltage busbars in electric vehicles, such as choosing the insulating layer material according to the range of expected mechanical loads.

International audience; A significant amount of retired lithium-ion car battery will be available by 2030. As an opportunity, they could be used to power less demanding applications while satisfying environmental and economic goals. Their eligibility to new applications can be assess by the means of two approaches: performing fast characterization tests or using their first use history when it is available. Given limited test equipment, a validation test is designed for both assessment approaches regarding crucial aspects of first and second life application, retirement point and fidelity.

This article presents how one can supply equipment which requires a regulated output and low ripple voltage such as HAM radios, which require a regulated 13.7V, by using a switch mode DC\DC converter powered up from an automotive battery. Car batteries can output 11.31V to 12.7V in normal state and cannot be fed to HAM radio equipment since they require 13.7V. Specially designed switch mode DC/DC converters with super low current and voltage ripple are required to supply them.

In this paper, we propose a low-cost arbitrary waveform generator to simulate battery voltage transients specified by ISO 16750–2 voltage profiles. The proposed methodology is based on the technique of direct digital synthesis (DDS) implemented in a microcontroller. The proposed approach allows reducing the amount of Flash memory used by the lookup table. The device generates several types of waveforms and uses a sequencer to combine them into the desired voltage profile. For testing purposes, emulations of the variations on the cranking voltage and the superimposed A.C. voltage are used to validate the proposed solution.

A series of integrated equalizers based on joint buck-boost (BB) and switched-capacitor (SC) converters are proposed for balancing the voltages of series-connected battery packs. All these equalizers realize the any-cells-to-any-cells (AC2AC) equalization mode without increasing the count of MOSFETs and drivers. Corresponding operational principles are analyzed and the expressions of balancing currents are derived by analytical methods and verified by experimental waveforms. According to the comparative balancing experiments for four and six series-connected Li-ion cells, one proposed CBB-PCSC equalizer, which achieves the dual AC2AC balancing modes through the integration of both coupled buck-boost (CBB) and parallel-connected switched-capacitor (PCSC) converters, leads to the highest balancing speed and efficiency. Moreover, compared with several conventional equalizers, this CBB-PCSC topology also has the compact size and low cost, making it become a well-performing integrated topology for automotive battery voltages equalization.

Natural fluoride contamination of drinking water is a serious issue that affects several countries of the world. Its negative health impact is well documented in the East African Rift Valley, where water consumption with fluoride (F−) concentration greater than 1.5 mg/L can cause fluorosis to people. Within the framework of the European Union (EU) Horizon 2020 FLOWERED project, we first designed an effective defluoridation device based on innovative application of octacalcium phosphate (OCP) and then explored its acceptance within rural communities. The prototype (FLOWERED Defluoridator Device [FDD]) essentially is composed of a 20‐L tank and a recirculating pump that guarantees the interaction between water and OCP. The device is powered by a car battery for a fixed pumping working time using a fixed amount of OCP for every defluoridation cycle. The results of tests performed in the rural areas of Tanzania show that a standardized use of the prototype can lower the dissolved F− from an initial concentration of 21 mg/L to below the World Health Organization (WHO) drinkable limit of 1.5 mg/L in 2 h without secondary negative effects on water quality. The approximate cost of this device is around US$220, whereas that of OCP is about $0.03/L of treated water. As with any device, acceptance requires a behavioral change on behalf of rural communities that needed to be investigated. To this end, we piloted a survey to explore how psychological and socioeconomic factors influence the consumption of fluoride‐free water. Results show that the adoption of FDD and OCP is more appealing to members of the rural communities who are willing to pay more and have a high consumption of water. Moreover, we suggest that given the low level of knowledge about fluorosis diseases, the government should introduce educational programs to make rural communities aware of the negative health consequences. Integr Environ Assess Manag 2020;16:856–870. © 2020 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC), KEY POINTS Octacalcium phosphate (OCP) can effectively remove fluoride (F−) from natural waters of the East African Rift Valley (EARV) through its transformation into fluorapatite (FAP).A new device for the treatment of fluoride‐polluted waters based on OCP has been presented: the FLOWERED Defluoridator Device (FDD). It has been tested and the results show that the FDD can be effectively applied in rural contexts.A standardized method for fluoride‐rich water treatment has been settled up: in 2 h of working time the FDD with 80 g of OCP can treat 20 L of natural water with F− concentration up to 21 mg/L.From socio‐economic analysis emerges that, given the poor knowledge of the risk of dental and skeletal fluorosis, the EARV governments should introduce educational programs to make rural communities aware of the negative health consequence of these diseases.

This paper presents performance improvement of old lead acid battery which usually used in car. When it is used in the long time, the efficiency is reduced. A problem is occurred because it is covered by sulfate on the surface of the lead plate electrode. This cause on current supply efficiency of the battery is decreased because resistance increases. This research presents the way to solve the problem. The sulfate must remove out of surface of the lead plate electrode. The high frequency stimulation signal generation is applied. A car battery 12 V 75 AH is experimentally tested. CCA meter model of AE300 is as a tool for efficiency observing. The high-frequency stimulation circuit at 64.7 kHz is designed. The experiments were done by applying DC voltage as a ripple high-frequency onto the electrode plates with different time intervals. The result shows that Cold Cranking Amp (CCA) value of the battery is increased. Therefore, it can be summarized that 64.7 kHz high frequency stimulation can increase the efficiency of battery.

This paper is focused on a two-stage LED driver architecture operating from an automotive battery input voltage and delivering independently regulated output currents to multiple LED strings. The system consists of a non-inverting buck-boost front end, which handles wide battery voltage range, followed by high-frequency immittance-network based LCL-T resonant converters, which operate as current sources over wide output voltage ranges. The two-stage architecture allows for system efficiency optimization by taking advantage of the passthrough mode of operation of the non-inverting buck-boost stage and the buck and boost regulation capabilities of the immittance network resonant converter stages. Experimental results are provided for a prototype consisting of a 400 kHz front-end stage and 2 MHz LCL-T stages delivering independently regulated 0.55 A currents to two LED strings with N = 1 —12 LEDs. The measured system efficiency is greater than 85% over wide input (8-18 V) and output (3-36 V) voltage ranges, with a peak efficiency of 93% when the buck-boost stage is in the pass-through mode at the nominal battery voltage.

In recent years, the automotive industry has seen rapid growth in autonomous vehicle and advanced driver- assistance system (ADAS) technologies. One of the key aspects of this technology is the parking assist system. The core function of a parking assist system is to help drivers in parking their vehicles safely and efficiently. This paper proposes a method for low-cost real-time semi-autonomous vehicle parking in which a Vision-Based Parking Assist System (VPAS) gives the driver maneuver recommendations for reverse bay parking. The proposed method integrates wide-angle lens correction, bird-eye surround view, and user-guided vision-based parking line detection as ways to calculate recommendations for the driver. VPAS aims for affordability and generality, thus it emphasizes streamlining most of the calculations to compensate for realtime needs while maintaining reliability in a relatively low-cost system that can be run on an entry-level traditional hatchback car. To verify the performance of the proposed methods, experiments on the integrated system are conducted in a controlled environment. From experimental results, we demonstrate the performance of VPAS in terms of real-time and accuracy aspects while running on a 4-cores 3.5 GHz processor powered by the car battery.

This paper reporst a research that was conducted to utilize lean method and failure mode and effects analysis (FMEA) in product costing, in order to obtain more rational price standard. FMEA as one of the methods to analyze risks is used in this paper as a tool to identify the risks from the waste side which is then adapted into a product costing in order to obtain a more rational product price structure. Utilizing both methods produce a waste priority number with adjustment value of 52.23% to the existing product cost. This adjustment makes the cost of product higher than before but yields less gap with the highest retail price

We investigate the effect of a novel switching device (Gallium Nitride based Junctionless FinFET) in lieu of the conventional silicon MOSFET, for the transmitter and receiver sections on a wireless mobile charging system operated by PMA standard of power transfer. In automobiles, input power at the transmitter section is supplied by car battery where its output voltage varies from 9V to 16V depending upon the engine rpm, electric-current used by the accessories, ambient temperate, and charge state of the battery. We aimed to improve the overall efficiency of the system so that it can provide a regulated output of 5V even at the lower minimum value of supply voltage. We show a 2% enhancement in efficiency with the novel switch, where the operating frequency is 240 kHz. The modified wireless system can help to charge mobiles, even when the car has a high need for energy.

Analysis of variance is an important method in exploratory and confirmatory data analysis when explanatory variables are discrete and response variables are continues and independent from each other. The simplest type of analysis of variance is one-way analysis of variance for comparison among means of several populations. In this paper, we extend one-way analysis of variance to a case where observed data are non-symmetric triangular fuzzy observations rather than real numbers. Meanwhile, a case study on the car battery length-life is provided on the basis on the proposed method.

The on-board batteries of the Emus have extremely high accuracy requirements for real-time estimation of state of charge (SOC). The ordinary Ah integration method and the open-circuit voltage method cannot meet the actual requirements of the Emus. This paper estimates the battery SOC based on the extended Kalman filter (EKF) algorithm. By building a first-order Thevenin equivalent circuit model to combining the car battery with the EKF algorithm, ultimately improve SOC estimation accuracy. In order to improve the estimation accuracy of the model, the variation law of the polarization voltage and polarization capacitance of the battery pack under different SOC values were obtained, and the functional relationship was fitted by the least square method. Finally, the simulation was performed in MATLAB / Simulink environment. The experimental results show that the EKF algorithm overcomes the shortcoming that the AH integration method cannot eliminate the accumulated error, and can implement the estimated battery SOC value, in addition the estimated error is controlled within 4%.

This paper deals with optimal charging versus aging minimization for lithium-ion batteries. The optimal charging strategy proposed involves charging controllers whose design relies on a battery model. The model, especially designed for automotive battery management systems applications, is recalled in this paper. It provides the voltage response of a cell to an input current. It also models side reactions that produce degradation mechanisms and thus decrease battery performance. Side reaction modelling involves taking into account the temperature cell variations, which are thus also modelled. The association of the three above-mentioned sub-models leads to an electro-thermal battery aging model used to design an optimal charging strategy that simultaneously takes into account the minimization of charging time and maximization of battery lifetime. Thus, to achieve a charging controller that manages battery health, an appropriate charging trajectory was computed by solving an optimization problem minimizing aging. Then, a charge control loop was designed. The nonlinear behavior of the battery was taken into account through the linearization of the electro-thermal aging model in different operating conditions. To take into account the resulting linear model family, the CRONE design methodology was used. The principles of this methodology are recapped and the design of the charging control loop is explained. The efficiency of the resulting charge controller is illustrated by several simulations.