@article{KotakKotakBradeetal.2021, author = {Kotak, Bhavya and Kotak, Yash and Brade, Katja and Kubjatko, Tibor and Schweiger, Hans-Georg}, title = {Battery Crush Test Procedures in Standards and Regulation: Need for Augmentation and Harmonisation}, volume = {7}, pages = {63}, journal = {Batteries}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2313-0105}, doi = {https://doi.org/10.3390/batteries7030063}, year = {2021}, abstract = {Battery safety is a prominent concern for the deployment of electric vehicles (EVs). The battery powering an EV contains highly energetic active materials and flammable organic electrolytes. Usually, an EV battery catches fire due to its thermal runaway, either immediately at the time of the accident or can take a while to gain enough heat to ignite the battery chemicals. There are numerous battery abuse testing standards and regulations available globally. Therefore, battery manufacturers are always in dilemma to choose the safest one. Henceforth, to find the optimal outcome of these two major issues, six standards (SAE J2464:2009, GB/T 31485-2015:2015, FreedomCAR:2006, ISO 12405-3:2014, IEC 62660-2:2010, and SAND2017-6295:2017) and two regulations (UN/ECE-R100.02:2013 and GTR 20:2018), that are followed by more than fifty countries in the world, are investigated in terms of their abuse battery testing conditions (crush test). This research proves that there is a need for (a) augmenting these standards and regulations as they do not consider real-life vehicle crash scenarios, and (b) one harmonised framework should be developed, which can be adopted worldwide. These outcomes will solve the battery manufacturers dilemma and will also increase the safety of EV consumers.}, language = {en} } @article{AhlbergTidbladEdstroemHernandezetal.2021, author = {Ahlberg Tidblad, Annika and Edstr{\"o}m, Kristina and Hern{\´a}ndez, Guiomar and de Meatza, Iratxe and Landa-Medrano, Imanol and Jacas Biendicho, Jordi and Trilla, Llu{\´i}s and Buysse, Maarten and Ierides, Marcos and Perez Horno, Beatriz and Kotak, Yash and Schweiger, Hans-Georg and Koch, Daniel and Kotak, Bhavya}, title = {Future Material Developments for Electric Vehicle Battery Cells Answering Growing Demands from an End-User Perspective}, volume = {14}, pages = {4223}, journal = {Energies}, number = {14}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14144223}, year = {2021}, abstract = {Nowadays, batteries for electric vehicles are expected to have a high energy density, allow fast charging and maintain long cycle life, while providing affordable traction, and complying with stringent safety and environmental standards. Extensive research on novel materials at cell level is hence needed for the continuous improvement of the batteries coupled towards achieving these requirements. This article firstly delves into future developments in electric vehicles from a technology perspective, and the perspective of changing end-user demands. After these end-user needs are defined, their translation into future battery requirements is described. A detailed review of expected material developments follows, to address these dynamic and changing needs. Developments on anodes, cathodes, electrolyte and cell level will be discussed. Finally, a special section will discuss the safety aspects with these increasing end-user demands and how to overcome these issues.}, language = {en} } @article{KotakMarchanteFernandezCanalsCasalsetal.2021, author = {Kotak, Yash and Marchante Fern{\´a}ndez, Carlos and Canals Casals, Lluc and Kotak, Bhavya and Koch, Daniel and Geisbauer, Christian and Trilla, Llu{\´i}s and G{\´o}mez-Nu{\~n}ez, Alberto and Schweiger, Hans-Georg}, title = {End of Electric Vehicle Batteries}, volume = {14}, pages = {2217}, journal = {Energies}, subtitle = {Reuse vs. Recycle}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en14082217}, year = {2021}, abstract = {It is a fact that electric vehicles (EVs) are beneficial for climate protection. However, the current challenge is to decide on whether to reuse an EV battery or to recycle it after its first use. This paper theoretically investigates these areas i.e., recycle and reuse. It was found that there are several commercially used recycling processes and also some are under research to regain maximum possible materials and quantity. The concept of reusing (second life) of the battery is promising because, at the end of the first life, batteries from EVs can be used in several applications such as storing energy generated from renewable sources to support the government grid. However, the cost and life-cycle analysis (LCA) demonstrated that there are several aspects involved in battery reuse applications. Henceforth, one LCA generalised method cannot provide an optimal approach for all cases. It is important to have a detailed study on each of the battery reusing applications. Until then, it is safe to say that reusing the battery is a good option as it would give some time to recycling companies to develop cost and energy-efficient methods.}, language = {en} } @techreport{BuysseIeridesPerezHornoetal.2021, author = {Buysse, Maarten and Ierides, Marcos and P{\´e}rez Horno, Beatriz and McCready, Amy and Kotak, Yash and Kotak, Bhavya and Schweiger, Hans-Georg}, title = {COBRA Market Intelligence Report - EV Safety and Testing: Feb-Mar-Apr 2021}, url = {https://projectcobra.eu/wp-content/uploads/2021/04/COBRA-MARKET-INTELLIGENCE-February-March-April-2021_789.pdf}, pages = {16}, year = {2021}, language = {de} } @article{KimStegerKotaketal.2019, author = {Kim, Woong-Ki and Steger, Fabian and Kotak, Bhavya and Knudsen, Peter V. R. and Girgsdies, Uwe and Schweiger, Hans-Georg}, title = {Water Condensation in Traction Battery Systems}, volume = {12}, pages = {1171}, journal = {Energies}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {1996-1073}, doi = {https://doi.org/10.3390/en12061171}, year = {2019}, abstract = {Lithium-ion traction battery systems of hybrid and electric vehicles must have a high level of durability and reliability like all other components and systems of a vehicle. Battery systems get heated while in the application. To ensure the desired life span and performance, most systems are equipped with a cooling system. The changing environmental condition in daily use may cause water condensation in the housing of the battery system. In this study, three system designs were investigated, to compare different solutions to deal with pressure differences and condensation: (1) a sealed battery system, (2) an open system and (3) a battery system equipped with a pressure compensation element (PCE). These three designs were tested under two conditions: (a) in normal operation and (b) in a maximum humidity scenario. The amount of the condensation in the housing was determined through a change in relative humidity of air inside the housing. Through PCE and available spacing of the housing, moisture entered into the housing during the cooling process. While applying the test scenarios, the gradient-based drift of the moisture into the housing contributed maximum towards the condensation. Condensation occurred on the internal surface for all the three design variants.}, language = {en} } @article{LottKotakBarraetal.2021, author = {Lott, Susanne and Kotak, Bhavya and Barra, S{\"o}nke and Schweiger, Hans-Georg}, title = {Nail Penetration of Small Pouch Cells Under Water: Investigation of Hydrofluoric Acid Formation in Dependence of the State of Charge}, volume = {168}, pages = {100505}, journal = {Journal of the Electrochemical Society}, number = {10}, publisher = {IOP Publishing}, address = {Bristol}, issn = {1945-7111}, doi = {https://doi.org/10.1149/1945-7111/ac285b}, year = {2021}, language = {en} }