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An efficient pack-level battery thermal management system is essential to ensure the safe driving experience of electric vehicles. In this work, we perform three-dimensional modeling of a liquid thermal management system for a real-world battery pack powering electrical vehicles. The effects of system structures, coolant flow direction layout, coolant flow rates, and inlet temperatures on the thermal performance are investigated. Under 2.0 C discharge, the system structure with interspersed cooling plates reduces the maximum temperature of the battery pack to 36.3 °C, which is 15% lower than that of the conventional design with bottom-mounted cooling plates. With the present system structure, around 62.2% of the heat produced by the batteries is dissipated. Moreover, the temperature difference is decreased by 10.5% with appropriately arranging coolant flow directions in different liquid cooling plates. In addition, increasing the coolant flow rate and lowering the inlet coolant temperature can greatly reduce the maximum battery temperature, while the latter parameter shows little influence on the pack temperature difference, which only changes 0.3 °C when the inlet temperature is decreased by 6 °C. This work provides valuable guidance for the development of pack-level liquid battery thermal management systems in electric vehicles.

Policymakers as well as corporate managers want to know how to gain the lead and benefit from a paradigmatic shift in technology. This paper develops and uses a combined policy and firm-level theoretical framework to derive policy implications from a case study of the development of battery, hybrid and fuel cell electric vehicles (BEVs, HEVs and FCVs) in Japan. Among the implications of the study, it is argued that Japanese national policy has so far had a limited direct role in the electrification of vehicles; this has been very largely decided and carried out in-house at the automakers. Policymakers need to consider this as well as the inherently international nature of the automotive industry. One key factor behind Toyota's and Honda's early and sustained lead in the electrification trajectory is the intense and in some aspects quite specific type of competition on the domestic market, which has nurtured firms with a strong product development capability. Finally, it is argued that the proposed theoretical framework contributes to a more balanced view of the role of policy in this potential paradigmatic shift in technology in a mature industry, compared to traditional policy or firm-level approaches.

Efficient thermal management is crucial for ensuring the safety and performance of lithium-ion batteries powering electric vehicles. Here, we develop a passive battery thermal management system with thermally enhanced water adsorbents by evenly loading MIL-101(Cr) particles onto a copper foam. MIL-101(Cr) particles can absorb water from the ambient and release water at an elevated temperature to dissipate heat, while the copper foam acts as a thermal conductive network to transfer the heat among the particles. The cooling performance of the system is tested under various battery working conditions. Results show that the thermal conductivity of the composite water adsorbent is increased to 1.9 W m−1 K−1, nearly 10 times of the pure MIL-101(Cr). Compared with natural cooling, air cooling and solid–liquid phase change material cooling, the proposed passive cooling method reduces the battery temperature by 7.5, 2.6, and 2.1 °C, respectively, at 3 C discharge. Additionally, the battery temperature and the temperature difference are confined below 37.6 and 1.5 °C in the dynamic discharge–charge cycling test. All these encouraging results indicate that the developed passive thermal management system achieves high cooling capability, good temperature uniformity, and zero energy consumption, which possesses a broad application prospect in electric vehicles. © 2022 Elsevier Ltd

A battery charging station (BCS) is a charging facility that supplies electric energy for recharging electric vehicles’ depleted batteries (DBs). A BCS has a certain number of charging bays and maintains a dynamic inventory of fully charged batteries (FBs). This paper studies a BCS scheduling (BCSS) problem whose target is to schedule the charging processes of the charging bays such that the charging cost is minimized while satisfying the FB demand. Specifically, the BCSS problem has two types of operations: 1) loading DBs into the charging bays and then unloading them to the FB inventory when they are fully charged and 2) controlling the charging rate of each charging bay. We formulate the BCSS problem as a mixed-integer program with quadratic battery degradation cost. A generalized benders decomposition algorithm is then developed to solve the problem efficiently. The salience of the developed algorithm is that: 1) each charging bay can solve its own subproblem separately and 2) each subproblem can be further partitioned into multiple independent and identically structured quadratic programming problems, and thus the algorithm facilitates an efficient parallel implementation. We perform extensive real data simulation to validate the optimization model and demonstrate the efficiency of the proposed algorithm.

Abstract The existence and dilemmas of metropolitan fisheries have been overlooked in research on the resilience of coastal marine socio-ecological systems. Yet, they could produce a model of sustainable fisheries with significant global impact. To fill that research gap, this study investigates an inshore fishery population that has sustained itself within Hong Kong's rapid urban development, seeking to understand the reasons for its survival. The results indicate that the values of self-reliance and entrepreneurialism exacted by fishing enabled the fishers to make necessary adaptations and reposition themselves in mariculture and service industries. These new ventures, while retaining marine-based livelihoods, draw the fishers away from fishing activities. The paradox of this value-based resilience of a metropolitan fishery is discussed for its potential to generate policies to strengthen linkages among the fishers’ business activities and to create a sustainable fishery model useful in other contexts.

Lithium-ion battery (LIB) is one of the core components of electric vehicles (EVs), and its ecological impacts are significant for the sustainable development of EVs. In this study, the carbon footprint of LIBs produced in China is investigated using a cradle-to-cradle life-cycle assessment approach. The results can be summarized as follows: (1) The carbon emission from battery production is 91.21 kg CO2-eq/kWh, in which the cathode production and battery assembly process are the main sources of carbon emissions; (2) The carbon emission during the battery use phase under China's electricity mix which is dominated by thermal power in 2020 is 154.1 kg CO2-eq/kWh; (3) Hydrometallurgy is the battery recycling method with the lowest carbon emission, and direct physical recycling method has attractive carbon reduction potential. (4) The carbon emission of battery remanufacturing through recycled materials is 51.8% lower than that of battery production with raw materials. Under the future electricity mix, the carbon emissions of battery production in 2050 and 2060 will be reduced by 75% and 84.9%, respectively. The short-term carbon reduction measure is battery recycling, and the long-term carbon reduction measure is the greening of electricity. © 2022 Elsevier Ltd

La promotion d'un comportement actif en matière de déplacements et la réduction des émissions de dioxyde de carbone (CO2) liées aux transports sont devenues une priorité dans de nombreuses villes chinoises connaissant un étalement urbain rapide et une plus grande dépendance à l'automobile. Cependant, peu d'études examinent de manière holistique les facteurs physiques et sociaux associés aux émissions de CO2 des voyages. À l'aide d'une enquête menée auprès de 1 525 acheteurs à Shenyang, en Chine, cette étude a estimé les émissions de CO2 liées aux déplacements liés aux achats et a examiné comment l'environnement bâti et les caractéristiques socio-économiques individuelles contribuent au comportement des déplacements liés aux achats et aux émissions de CO2 associées. Nous avons constaté que, tout d'abord, les trajets en voiture privée génèrent en moyenne près de huit fois plus d'émissions de carbone que les trajets shopping en transports en commun. Deuxièmement, il y avait une autocorrélation spatiale significative avec les émissions de CO2 par trajet, et les émissions de carbone les plus élevées étaient concentrées dans les banlieues intérieures et entre les première et deuxième routes circonférentielles. Troisièmement, les émissions de CO2 par voyage lors des achats étaient négativement corrélées à plusieurs caractéristiques de l'environnement bâti, notamment la densité de population, la quantité de stations de transport public, la densité des routes et la densité des magasins. Ils se sont également révélés être significativement liés aux caractéristiques socio-économiques individuelles de la possession d'une voiture, du statut d'emploi et du niveau d'éducation à l'aide d'un modèle de régression logistique multinomiale. Ces résultats empiriques ont des implications politiques importantes, aidant à l'élaboration de mesures qui contribuent à la durabilité du transport urbain et à la réalisation des objectifs d'atténuation des émissions de carbone. Promover un comportamiento de viaje activo y disminuir las emisiones de dióxido de carbono (CO2) relacionadas con el transporte se han convertido en una prioridad en muchas ciudades chinas que experimentan una rápida expansión urbana y una mayor dependencia del automóvil. Sin embargo, hay pocos estudios que examinen de manera integral los factores físicos y sociales asociados con las emisiones de CO2 de los viajes. Utilizando una encuesta de 1525 compradores realizada en Shenyang, China, este estudio estimó las emisiones de CO2 de los viajes relacionados con las compras y examinó cómo el entorno construido y las características socioeconómicas individuales contribuyen al comportamiento de los viajes de compras y las emisiones de CO2 asociadas. Descubrimos que, en primer lugar, los viajes en coche privado generan casi ocho veces más emisiones de carbono que los viajes de compras en transporte público, de media. En segundo lugar, hubo una autocorrelación espacial significativa con las emisiones de CO2 por viaje, y las emisiones de carbono más altas se agruparon en los suburbios interiores y entre la primera y la segunda carreteras circunferenciales. En tercer lugar, las emisiones de CO2 por viaje de compras se correlacionaron negativamente con varias características del entorno construido, incluida la densidad de población, la cantidad de estaciones de transporte público, la densidad de carreteras y la densidad de tiendas. También se encontró que estaban significativamente relacionados con las características socioeconómicas individuales de la propiedad del automóvil, el estado de empleo y el nivel de educación utilizando un modelo de regresión logística multinomial. Estos hallazgos empíricos tienen importantes implicaciones políticas, ya que ayudan a desarrollar medidas que contribuyen a la sostenibilidad del transporte urbano y cumplen con los objetivos de mitigación de carbono. Promoting active travel behavior and decreasing transport-related carbon dioxide (CO2) emissions have become a priority in many Chinese cities experiencing rapid urban sprawl and greater automobile dependence. However, there are few studies that holistically examine the physical and social factors associated with travel CO2 emissions. Using a survey of 1525 shoppers conducted in Shenyang, China, this study estimated shopping-related travel CO2 emissions and examined how the built environment and individual socioeconomic characteristics contribute to shopping travel behavior and associated CO2 emissions. We found that, firstly, private car trips generate nearly eight times more carbon emissions than shopping trips using public transport, on average. Second, there was significant spatial autocorrelation with CO2 emissions per trip, and the highest carbon emissions were clustered in the inner suburbs and between the first and second circumferential roads. Third, shopping travel CO2 emissions per trip were negatively correlated with several built environment features including population density, the quantity of public transport stations, road density, and shop density. They were also found to be significantly related to the individual socio-economic characteristics of car ownership, employment status, and education level using a multinomial logistic regression model. These empirical findings have important policy implications, assisting in the development of measures that contribute to the sustainability of urban transportation and meet carbon mitigation targets. أصبح تعزيز سلوك السفر النشط وتقليل انبعاثات ثاني أكسيد الكربون المرتبطة بالنقل أولوية في العديد من المدن الصينية التي تشهد انتشارًا حضريًا سريعًا واعتمادًا أكبر على السيارات. ومع ذلك، هناك عدد قليل من الدراسات التي تدرس بشكل شامل العوامل المادية والاجتماعية المرتبطة بانبعاثات ثاني أكسيد الكربون أثناء السفر. باستخدام دراسة استقصائية شملت 1525 متسوقًا أجريت في شنيانغ، الصين، قدرت هذه الدراسة انبعاثات ثاني أكسيد الكربون المتعلقة بالسفر أثناء التسوق وفحصت كيف تساهم البيئة المبنية والخصائص الاجتماعية والاقتصادية الفردية في سلوك السفر أثناء التسوق وانبعاثات ثاني أكسيد الكربون المرتبطة به. وجدنا، أولاً، أن رحلات السيارات الخاصة تولد ما يقرب من ثمانية أضعاف انبعاثات الكربون مقارنة برحلات التسوق باستخدام وسائل النقل العام، في المتوسط. ثانيًا، كان هناك ارتباط ذاتي مكاني كبير بانبعاثات ثاني أكسيد الكربون لكل رحلة، وتم تجميع أعلى انبعاثات الكربون في الضواحي الداخلية وبين الطرق المحيطية الأولى والثانية. ثالثًا، ارتبطت انبعاثات ثاني أكسيد الكربون الناتجة عن السفر للتسوق سلبًا بالعديد من ميزات البيئة المبنية بما في ذلك الكثافة السكانية وكمية محطات النقل العام وكثافة الطرق وكثافة المتاجر. كما وجد أنها مرتبطة بشكل كبير بالخصائص الاجتماعية والاقتصادية الفردية لملكية السيارات، والوضع الوظيفي، ومستوى التعليم باستخدام نموذج الانحدار اللوجستي متعدد الحدود. هذه النتائج التجريبية لها آثار مهمة على السياسة، وتساعد في تطوير التدابير التي تسهم في استدامة النقل الحضري وتفي بأهداف التخفيف من الكربون.

To accommodate the increasing electric vehicle (EV) penetration in distribution grid, coordinated EV charging has been extensively studied in the literature. However, most of the existing works optimistically consider the EV charging rate as a continuous variable and implicitly ignore the capacity limitation in distribution transformers, which both have great impact on the efficiency and stability of practical grid operation. Towards a more realistic setting, this paper formulates the EV coordinated discrete charging problem as two successive binary programs. The first one is designed to achieve a desired aggregate load profile (e.g., valley-filling profile) at the distribution grid level while taking into account the capacity constraints of distribution transformers. Leveraging the properties of separable convex function and total unimodularity, the problem is transformed into an equivalent linear program, which can be solved efficiently and optimally. The second problem aims to minimize the total number of on-off switchings of all the EVs’ charging profiles while preserving the optimality of the former problem. We prove the second problem is NP-hard and propose a heuristic algorithm to approximately achieve our target in an iterative manner. Case studies confirm the validity of our proposed scheduling methods and indicate our algorithm’s potential for real-time implementations.

Lithium-ion batteries (LIBs) are the ideal energy storage device for electric vehicles, and their environmental, economic, and resource risks assessment are urgent issues. Therefore, the life cycle assessment (LCA) of LIBs in the entire lifespan is becoming a hotspot. This study first reviews the basic framework and types, standards and methods, and technical challenges of LCA. Then, the cradle-to-cradle LCA framework for LIBs is constructed, and the technical route of LCA in the stages of battery production, usage, secondary utilization, and material recycling are analyzed in detail. Finally, the carbon footprint in the battery production and recycling stages is conducted under the current and future energy mixes. The results show that battery production significantly impacts the environment and resources, and battery materials recycling and remanufacturing present considerable environmental and economic values. Moreover, the greening of electricity is critical to reducing carbon emissions during the battery life cycle.