Mobile Sector Research Articles

Ultrafast Laser Patterning of Silicon/Graphite Composite Electrodes to Boost Battery Performance

The ever-increasing share of electric vehicles in the mobility sector urgently calls for an increase in the production capacity of high-power and high-energy lithium-ion batteries with low production costs. A gravimetric energy density of about 350 Wh/kg flanked by a volumetric energy densities of at least 750 Wh/L were defined as ambitious goals from the European Union to be achieved by 2025. For this purpose, novel, high-capacity anode materials containing significant silicon content should be utilized in next generation batteries. At room temperature, silicon has a theoretical specific capacity of 3579 mAh/g which is one order of magnitude higher compared to the state-of-the-art graphite anode material (372 mAh/g). The volume change which silicon undergoes during lithiation and delithiation and the thereby caused mechanical stresses inside the composite electrode, which lead to loss of electrical contact and delamination, are an obstacle for its implementation in industrial battery production. While many researchers focus on other promising approaches to facilitate the usage of silicon in electrodes, for example pre-lithiation, the usage of graphite-silicon composites, or carbon coating on the silicon particles, here, the implementation of additional porosity via laser patterning is pursued. A water-based silicon/graphite slurry concept for the large-scale electrode production is used. There, the silicon nanoparticles’ agglomerates are destroyed and the silicon is finely dispersed using a ball mill, while the slurry homogenization is finalized using a disk stirrer. This facilitates the production of electrode sheets on a roll-to-roll coater, delivering enough material for the high power, high repetition rate roll-to-roll laser patterning process, both of which exhibit a technology readiness level of 5 to 6. The slurry and electrode characterizations are performed using laser induced breakdown spectroscopy (LIBS) for both the binder and lithium spatial distribution, the cyclability and lifetime of the electrodes is assessed in pouch cells with NMC 622 as counter electrode, and the lithiation of the composite material is determined with cyclic voltammetry. Scanning electron, digital and light microscopy are used for the characterization of the laser patterning, while chemical analysis is used to assess the composition of the electrode and the silicon oxidation during water-based manufacturing.

Structural Batteries – the Best or Worst of Two Worlds

The electrification of road transport is continuously progressing, and concomitantly lithium-ion batteries are developing towards higher energy densities. However, the theoretical limitations of this technology are expected to be reached in the coming years [1], leaving more demanding applications, like aeronautic ones, with high challenges regarding fully battery electric propulsion of commercial aircrafts. Structural batteries (or multifunctional energy storage), i.e. batteries which show sufficient mechanical stability to substitute conventional composite materials in load bearing structures, show a promising way to resolve this issue. Due to their multifunctional properties, structural batteries can replace interior and exterior elements of e.g. an airplane, and thus provide at best energy storage without weight increase [2].The idea of structural batteries emerged around 20 years ago, and different cell designs have been proposed including coaxial wires [3] and planar reinforced stacks [4]. Nevertheless, high degrees of multifunctionality could not be realized and the approach was never industrially applied [5]. Recently, the need to electrify the mobility sector and the prospect of massless energy storage has reincited a lot of new research activities around this topic.The main challenge at electrochemistry level for the development of structural batteries is to find an alternative electrolyte for the conventionally used carbonate-based liquid ones which provide only negligible mechanical stability. Apart from high ionic conductivities and safety, the additional requirements for the structural electrolyte include high mechanical capabilities (e.g. high Young’s modulus), good adhesion to all cell components, as well as high thermal stability. The latter is especially important for implementation of the structural batteries in composite structures, which are usually cured at elevated temperatures well beyond the stability range of conventional electrolytes. These demanding specifications render the use of conventional lithium-ion battery components formassless energy storage as futile.In this work, two different approaches for the development of electrolytes for structural batteries are discussed. The first one employs a bi-continuous electrolyte based on thermoset materials, whereas the second one uses a gel electrolyte. For the former two separate phases form percolating networks with different properties throughout the electrolyte membrane. One phase provides high ionic conductivity to achieve high electrochemical performance of the cells, whereas the other one yields high mechanical strength. The second approach uses a mono-phasic electrolyte which provides both, electrochemical as well as mechanical performance. The two approaches are further compared and discussed, focusing on their applicability for structural batteries. Important parameters like processability and feasibility for implementation into a composite structure, which are often neglected, are addressed, enabling a holistic view on this technology.

Exploring Operando Electrochemical Techniques to Track Degradation Mechanisms in Li-Ion Batteries

The battery field has recently received unprecedented attention and investments in order to handle the upcoming demands of energy storage notably from the electric mobility sector. The pursuit of higher performance batteries that store more energy, charge faster and have a longer life cycle has been converted into studies for new electrode materials, coatings, electrolytes, among others that often find the common key challenge of the performance decline. The precise identification of the degradation mechanisms and their tracking along aging is thus essential to pave the way for the next generation batteries. For that several methods are employed although most of them are not in operando, not following the practical cell operation. In that context, this paper introduces a set of operando electrochemical techniques that are still largely underexploited but that can be coupled and offer broader comprehension of the degradation mechanisms through deeper than usual analysis of electrochemical data. Taking insertion cells (like Li ion or Na ion batteries) as example it is first shown how differential techniques like incremental capacity analysis (ICA or dQ/dV vs V) and differential voltage analysis (DVA or dV/dQ vs Q) allow to identify main degradation mechanisms in the positive and in the negative electrodes separately by following their active material masses and their curves dynamics (relative displacement of the potential x capacity curves, the slippage) in a two electrodes configuration. For that the in house and free access developed software Electrochemical Visualization Application (EVA) is employed. In addition, using defined protocols, other techniques as Distribution of Relaxation Times (DRT) are coupled to those first analyses in order to complement the understanding of the degradation mechanisms in each electrode. This presentation intends to show an introduction of how to deeper analyze electrochemical techniques to follow loss of mass and lithium ion inventory from each electrode along aging, how to use the DRT with the ICA and DVA to identify the evolution of Impedance from each electrode along aging and how to build protocols that allow to couple those techniques minimizing any eventual degradation interference from those techniques, that all shown through experimental results and with the aid of a free and open software for the part of the ICA and DVA analyses. Figure 1

Adsorbed Gas Storage Digital Twin

One possibility for energy storage are fuels. With gaseous fuels like hydrogen or methane, significant efforts are necessary for a feasible storage in terms of compression or liquefaction. This is of particular importance in the mobility sector. An alternative to high-pressure or cryogenic gas storage is the storage by adsorption in porous media using nano-carbons, metal–organic frameworks, or metal hydrides as adsorbents. In order to assess the performance of the charging and discharging of adsorption tanks, the mass and energy balance as well as the phase equilibrium (adsorption isotherm) and, if present, the spatial distribution of properties has to be considered. In order to simplify the analysis and prediction of these models, an attempt is made to develop digital twins based on machine learning. Neural networks and Gaussian process regression are applied to replace the system of coupled nonlinear and differential equations. The data basis used is generated by simulations. Thus, it is possible to easily predict the performance of a storage tank for different gases or to determine an optimum storage device (material selection and tank design).

External effects of urban automated vehicles on sustainability

The transport sector is responsible for an important share of pollutant emissions, and urban mobility systems are facing major challenges, such as congestion and parking needs. Automated vehicles are expected to mitigate effects of this kind, and may positively affect the sustainability of the mobility sector. We quantify the external effects of human-driven battery electric vehicles in comparison to automated ones, regarding external costs for urban areas in Germany. In our analysis we focus on environmental, social and economic external cost components. We find that vehicle automation can lower external costs by 34%, suggesting savings of 51.6 billion euros per year for Germany alone, with congestion and parking space costs accounting for the largest share of costs and savings. Our results provide an understanding of the magnitude of the external effects of automated vehicles, conducting sensitivity analyses and additionally discussing the impact of travel behavior.

Implementation of Area Efficient Carry Select Adder using Binary to Excess1 Code

Adders are widely used as essential parts in the design of digital integrated circuits. The Carry Select Adder (CSA) is unique among conventional adder topologies in that it operates quickly. There is a need for speedier arithmetic units as well as ones that use less power and take up less space as the mobile sector grows quickly. The Carry-Select method for adder design with carry propagation achieves a good trade-off between performance and cost. However, because it uses two ripple carry adders (RCA), the traditional CSA design still has a significant area overhead. A Binary to Excess-1 code converter (BE-1 converter) has been used in the development of a modified CSA design to overcome the issue. This study presents a practical method for reducing the size and power footprint of the CSA by introducing gate-level changes to the BE-1 converter design. Making use of this alteration, a 4-bit CSA architecture with a BE-1 converter is developed and contrasted with the industry standard CSA design. These designs are evaluated considering their area and power characteristics. The analytical results show that the suggested CSA structure is better than the traditional one and that using a CSA with a BE-1 converter is an efficient way to create a VLSI design.

MOBI-Qual: a common framework to manage the product-service system quality of shared mobility

AbstractShared mobility is transforming urban transportation. The increasing demand for more efficient and sustainable transportation options has driven the growth of the shared mobility sector, attracting operators ranging from new entrants to traditional manufacturers looking to diversify their markets. Despite its popularity, there is currently a lack of tools to support the design and management of the quality of shared mobility. Seeking to contribute towards bridging this gap, this paper presents a comprehensive quality framework, refereed as MOBI-Qual. MOBI-Qual was developed using a bottom-up approach, wherein quality determinants were defined based on an extensive analysis of digital Voice-of-Customer data, specifically customer review. A topic modelling algorithm was utilized to extract the quality determinants for the most prevalent shared mobility modes. Following this, a common framework was established through a comparison of these quality determinants. The proposed framework comprises eleven quality determinants that comprehensively cover various aspects of shared mobility.

Analysing user well-being in ridehailing services

Purpose Although the sharing economy improves comfort and convenience, it is yet unclear how it affects subjective well-being. This study aims to offer a conceptual model for understanding the linkages between the antecedents and consequences of subjective well-being in ridehailing services. Design/methodology/approach Using a non-probabilistic sampling method and a pre-tested survey instrument, 450 responses were collected from January to March 2020. The data were analysed using structural equation modelling. Findings Experience quality and perceived convenience are correlated with subjective well-being. Perceived value and personal innovativeness were not correlated with subjective well-being, as the former does not contribute to the latter’s development. Continuous usage intention significantly correlated with subjective well-being, followed by customer relationship proneness and advocacy. Regarding gender and age differences, men place higher value on customer relationship proneness than women, while women place higher value on subjective well-being than men. Older users value perceived convenience and customer relationship proneness in ridehailing services more than younger users. Practical implications Understanding key factors contributing to user well-being in ridehailing would promote a more affordable mobility sector globally. This understanding would enable ridehailing businesses to create more effective business and marketing plans while prioritising user well-being, thus enhancing user happiness and reducing turnover rates. Originality/value This research demonstrates how crucial it is for users’ well-being to have a positive experience and find the service convenient. It also highlights the importance of building strong customer relationships and examines how gender and age influence people’s adoption and use of these services.

Liquefied hydrogen value chain: A detailed techno-economic evaluation for its application in the industrial and mobility sectors

Green hydrogen can be efficiently produced in regions rich in renewable sources, far from the European large-production sites, and delivered to the continent for utilization in the industrial and mobility sectors. In this work, the transportation of hydrogen from North Africa to North Italy in its liquefied form is considered. A techno-economic assessment is performed on its value chain, which includes liquefaction, storage, maritime transport, distribution, regasification and compression. The calculated transport cost for the industrial application (delivery to a hydrogen valley) ranges from 6.14 to 9.16 €/kg, while for the mobility application (delivery to refueling stations) the range is 10.96–17.71 €/kg. In the latter case, the most cost-effective configuration involves the distribution of liquefied hydrogen and regasification at the refueling stations. The liquefaction process is the cost driver of the value chain in all the investigated cases, suggesting the importance of its optimization to minimize the overall transport cost.

A methodological framework for geospatial modelling of hydrogen demand in cities

Urban energy system planning is vital for cities shifting towards a more sustainable and integrated energy system. Hydrogen is considered one of the most promising solutions in future energy systems. Previous work on hydrogen energy systems predominantly analysed hydrogen models on a national level or only parts of the mobility sector. This indicates a research gap for geospatial models that include multiple sectors in which hydrogen can be used. These models can be used to support decision-making processes around the hydrogen economy in cities. This study presents a holistic model addressing the geospatial modelling of hydrogen demand in urban areas. It proposes a method that integrates a variety of open source data, including geodata, earth observation data and energy data to estimate hydrogen demand top down for the industrial feedstock (steel, ammonia, organic chemistry), process heating, and mobility (buses, trucks, trains, airplanes, ships) sectors. The proposed method can also be extended to different sectors. The method is validated by modelling the hydrogen demand in all German cities and benchmarking it with national studies. This study’s results are within the same range as the results of national studies. For this paper, the method is applied for two case studies in Freiburg im Breisgau and Frankfurt am Main. Applying this method in urban areas shows potential hydrogen demand hotspots in these areas. The model’s results help policymakers and industry stakeholders make informed decisions about the development of hydrogen infrastructure and facilitate the adoption of hydrogen as a low-carbon energy carrier. Future research could explore the temporal aspects of hydrogen demand and the spatial influence of hydrogen demand on future hydrogen production facilities such as electrolysers.

Unified model of lithium-ion battery and electrochemical storage system

Nowadays, energy storage systems are of paramount importance in sectors such as renewable energy production and sustainable mobility because of the energy crisis and climate change issues. Although there are various types of energy storage systems, electrochemical devices such as electric double layer capacitors (EDLCs), lithium-ion capacitors (LiCs), and lithium-ion batteries (LiBs) are the most common because of their high efficiency and flexibility. In particular, LiBs are broadly employed in many applications and preferred in the mobility sector, where there is a need for high energy and high power. To ensure good operating conditions for a battery and limit its degradation, it is important to have a precise model of the device. The literature contains numerous equivalent circuit models capable of predicting the electrical behavior of an LiB in the time or frequency domain. In most of them, the battery impedance is in series with a voltage source modeling the open circuit voltage of the battery for simulation in the time domain. This study demonstrated that an extension of a model composed exclusively of passive elements from the literature for EDLCs and LiCs would also be suitable for LiBs, resulting in a unified model for these types of electrochemical storage systems. This model uses the finite space Warburg impedance, which, in addition to the diffusion process of lithium\\lithium ions in the electrodes\\electrolyte, makes it possible to consider the main capacitance of the battery. Finally, experimental tests were performed to validate the proposed model.

Decoding Private or Commercial Vehicle Ownership Decisions for Low-Carbon Mobility Transitions: A Systematic Review of the Literature

Increase in vehicle ownership (VO) as a result of rapid economic and population growth and its negative environmental effects have gradually become a potential threat to the physical and social environment. A wide range of factors influences the propensity for VO by individuals or firms; however, the existing body of literature lacks a critical review which provides an understanding of their underlying associations and potential implications for policymaking in one holistic frame. To fill this research gap, this study presents a systematic review of factors affecting private and commercial VO using the PRISMA framework (Preferred Reporting Items for Systematic Reviews and Meta-Analysis). The factors influencing private VO decisions are extracted from the reviewed articles; subsequently, the identified factors are topologically divided into seven categories. The findings show that most studies identified the factors contributing to VO as related to socio-economic, demographic, and built environmental characteristics. A lack of research has been identified for attitudinal, technological, and parking-related variables. It is also concluded that there are gaps in the knowledge base on factors contributing to the commercial VO of a business establishment. Designing informed policy measures based on such factors that can induce a sustainable transition in the mobility sector is important to mitigate transportation-related negative externalities on the environment. The overall review findings offer actionable guidance for low-carbon mobility transition and outline a future research agenda for academic researchers and decision makers. The quantifiable factors revealed in this study are expected to assist policy makers in discouraging VO propensity among individuals or firms.

Product-service system-oriented business models: a taxonomy of startups in the mobility sector

Startups are becoming increasingly important in the mobility sector and are putting established companies under pressure to adapt their business models. Especially, the automotive industry faces a significant change from an automotive manufacturer towards a mobility provider. However, literature does not provide a comprehensive understanding of the elements and archetypes of product-service system-oriented business models of startups in the mobility sector. This paper provides a taxonomy with six dimensions and 55 characteristics based on the analysis of 34 startups’ business models. Four clusters can be described as the result of a cluster analysis. Thus, a deeper understanding of the business models and a starting point for future research and practical application is provided. Furthermore, based on the results, implications for research and practice like dominated characteristics of product-service system-oriented business models as well as future research directions are pointed out.

Refuelling tests of a hydrogen tank for heavy-duty applications

A transition towards zero-emission fuels is required in the mobility sector in order to reach the climate goals. Here (green) renewable hydrogen for use in fuel cells will play an important role, especially for heavy duty applications such as trucks. However, there are still challenges to overcome regarding efficient storage, infrastructure integration and optimization of the refuelling process. A key aspect is to reduce the refuelling duration as much as possible, while staying below the maximum allowed temperature of 85 °C. Experimental tests for the refuelling of a 320 l type III tank were conducted at different operating conditions and the tank gas temperature measured at the front and back ends. The results indicate a strongly inhomogeneous temperature field, where measuring and verifying the actual maximum temperatures proves difficult. Furthermore, a simulation approach is provided to calculate the average tank gas temperature at the end of the refuelling process.

Navigating the New Product Development Process: A Case Study of a Startup’s Journey from Ideation to Commercializatio

New Product Development (NPD) is a critical yet challenging aspect of business development, with failure rates ranging from 40% to 80%. This challenge is particularly pronounced in startups, which form the backbone of most developed economies. Despite their importance, startups often struggle with NPD, with some studies suggesting a failure rate as high as 90%. This research paper contributes to the existing literature by examining the NPD journey of a technology startup, Plugable. Plugable, an Irish enterprise in the mobility sector, aims to create a platform similar to Airbnb for private Electrical Vehicle (EV) chargers. The paper traces the journey of two products the company attempted to launch. The first product did not reach the launch stage, leading the business to revise its strategy and develop Plugable. At the time of writing, Plugable is at the prototype stage, having secured €50,000 in external funding and won several national business awards. The case study provides several key learnings for entrepreneurs in the NPD space. It underscores the importance of accurately defining the problem statement, the critical role of validation, and the significance of assembling the right team to develop an effective go-to-market strategy. These findings contribute to the emerging body of knowledge on NPD within the startup context, providing practical insights into the application of established NPD models. Furthermore, the study offers valuable insights into technology startups' unique challenges during the NPD process.

Green products in the insurance market

The decarbonization of economy and, more specifically, the widespread deployment of systems that produce energy from renewable sources require substantial insurance cover, as such a transition process contains the seeds of new individual and systemic risks. The new regulations in Europe, aimed at creating incentives for transition to green economy, with the changes in consumer preferences, support the demand for insurance products tied to the sector of renewable energy, energy efficiency and sustainable mobility. They are seeking at building up an appropriate institutional environment to push the demand for green insurance products. Faced with this challenge, the purpose of this article is to present green insurance products, review the legislative foundations and summarize the weaknesses that have emerged in the creation and management of such innovative products.

Évaluation de la fiabilité de l’examen clinique de la hanche de l’enfant paralysé cérébral

The incidence of cerebromotor disorders of cerebral palsied subjects on their orthopedic state is a constant: excess contractions leading to misalignments, muscular and periarticular retractions, displacements of mobility sectors, bone deformations These orthopedic consequences are correlated to the degree motor impairment. Rehabilitation, orthopaedic, medical and surgical treatments find their relevance all the more so if the factors of the disorders are correctly identified, evaluated qualitatively and quantitatively. The contributions of clinical and paraclinical examinations complement each other to provide professionals with the richest range possible. In 1991, Dr Alain Lespargot described a clinical examination allowing to define the sectors of mobility where the hip is in a situation of satisfactory centering or on the contrary, of less centering. This article studies the interest of this examination in addition to radiography. This is a first step to show that this clinical examination effectively accounts for the centering situation of the hips flexed around 90°. It is reliable and reproducible. However, it requires some practice and repetition, like many of our other professional gestures.

Citizens call for sufficiency and regulation — A comparison of European citizen assemblies and National Energy and Climate Plans

There is a growing body of scientific evidence supporting sufficiency as an inevitable strategy for mitigating climate change. Despite this, sufficiency plays a minor role in existing climate and energy policies. Following previous work on the National Energy and Climate Plans of EU countries, we conduct a similar content analysis of the recommendations made by citizen assemblies on climate change mitigation in ten European countries and the EU, and compare the results of these studies. Citizen assemblies are representative mini-publics and enjoy a high level of legitimacy.We identify a total of 860 mitigation policy recommendations in the citizen assemblies’ documents, of which 332 (39 %) include sufficiency. Most of the sufficiency policies relate to the mobility sector, the least relate to the buildings sector. Regulatory instruments are the most often proposed means for achieving sufficiency, followed by fiscal and economic instruments. The average approval rate of sufficiency policies is high (93 %), with the highest rates for regulatory policies.Compared to National Energy and Climate Plans, the citizen assembly recommendations include a significantly higher share of sufficiency policies (factor three to six) with a stronger focus on regulatory policies. Consequently, the recommendations can be interpreted as a call for a sufficiency turn and a regulatory turn in climate mitigation politics. These results suggest that the observed lack of sufficiency in climate policy making is not due to a lack of legitimacy, but rather reflects a reluctance to implement sufficiency policies, the constitution of the policy making process and competing interests.

The volatility spillover between battery metals and future mobility stocks: Evidence from the time-varying frequency connectedness approach

The transition to clean energy in the mobility sector, like other green solutions, necessitates a heightened dependence on critical minerals. The escalating demand for minerals, coupled with supply-side challenges, intensifies the price volatility of battery metals, which are crucial for ensuring sustainable production in the future mobility ecosystem. This paper examines the volatility connectedness between battery metals prices and stock prices of corporations engaging in future mobility between March 20, 2012, and March 2, 2022. We analyze the volatility of six base metals (i.e., aluminum, copper, lead, nickel, tin, and zinc), three minor metals (i.e., lithium, cobalt, manganese), and the Solactive Electric Vehicles and Future Mobility Index. We employ the novel frequency connectedness framework to identify the volatility spillovers and contagion among the variables across different investment horizons in a time-varying fashion. The future mobility equity market is a net volatility recipient, and copper and lithium are the dominant net volatility transmitters, emphasizing the pivotal role of battery metals in shaping the dynamics of the future mobility industry. We construct a minimum connectedness portfolio, offering significant hedging effectiveness for market participants. Finally, policy implications are discussed.

Tracking Resistance in Polymeric Insulation Materials for High-Voltage Electrical Mobility Applications Evaluated by Existing Test Methods: Identified Research Needs.

With the increasing electrification of the transportation and mobility sectors, polymer insulation materials are inevitably exposed to harsher environments, including exposure to contamination, wide temperature ranges, operation at higher voltages and switching frequencies, and low-pressure environments. This paper reviews the tests to characterize the polymeric materials used in insulation systems for electric mobility applications, focusing on resistance to tracking. This paper also reports on the limitations of existing standard test methods and identifies the challenges and research needs to meet the increasing demands of the electric mobility industry. To this end, an evaluation of the scientific and technological state of the art is carried out through the analysis of theses, research articles, technical reports, manufacturers' datasheets, international standards, and white papers.