sustainability Article Advances of 2nd Life Applications for Lithium Ion Batteries from Electric Vehicles Based on Energy Demand Aleksandra Wewer, Pinar Bilge * and Franz Dietrich Institute for Machine Tools and Factory Management (IWF), Technische Universität Berlin, 10587 Berlin, Germany; [email protected] (A.W.); [email protected] (F.D.) * Correspondence: [email protected]; Tel.: +49-(30)-314-27091 Abstract: Electromobility is a new approach to the reduction of CO2 emissions and the deceleration of global warming. Its environmental impacts are often compared to traditional mobility solutions based on gasoline or diesel engines. The comparison pertains mostly to the single life cycle of a battery. The impact of multiple life cycles remains an important, and yet unanswered, question. The aim of this paper is to demonstrate advances of 2nd life applications for lithium ion batteries from electric vehicles based on their energy demand. Therefore, it highlights the limitations of a conventional life cycle analysis (LCA) and presents a supplementary method of analysis by providing the design and results of a meta study on the environmental impact of lithium ion batteries. The study focuses on energy demand, and investigates its total impact for different cases considering 2nd life applications such as (C1) material recycling, (C2) repurposing and (C3) reuse. Required reprocessing methods such as remanufacturing of batteries lie at the basis of these 2nd life applications. Batteries are used in their 2nd lives for stationary energy storage (C2, repurpose) and electric vehicles (C3, Citation: Wewer, A.; Bilge, P.; reuse). The study results confirm that both of these 2nd life applications require less energy than Dietrich, F. Advances of 2nd Life the recycling of batteries at the end of their first life and the production of new batteries. The paper Applications for Lithium Ion Batteries concludes by identifying future research areas in order to generate precise forecasts for 2nd life from Electric Vehicles Based on applications and their industrial dissemination. Energy Demand. Sustainability 2021, 13, 5726. https://doi.org/10.3390/ Keywords: circular economy; remanufacturing; multiple life cycles; electromobility; lithium ion bat- su13105726 tery Academic Editors: Knut Blind, Simone Wurster, Rainer Walz, Katrin Ostertag and Henning Friege 1. Introduction Received: 23 March 2021 Electromobility is an approach that aims to reduce CO2 emissions and to decelerate Accepted: 16 May 2021 global warming. Scientific papers, reports and news often compare the environmental Published: 20 May 2021 impacts of electromobility to traditional mobility solutions with gasoline or diesel en- gines [1–5]. Some of these investigations address the question of whether electromobility Publisher’s Note: MDPI stays neutral has, among others, a better CO2 footprint. Regardless of whether it is better, the same or with regard to jurisdictional claims in even worse than combustion technology, electromobility will be present in the future and published maps and institutional affil- continue to gain importance following a political urge and past investments. In any future iations. case, large quantities of used batteries will occur that need to be treated. The total demand for batteries is estimated to be 200 GWh by the year 2025, four-fold more than in the year 2020 [6]. If the total impact can be robustly assessed, it can influence the decision for or against a specific 2nd and End of Life (EoL) strategy. The total environmental impact of a Copyright: © 2021 by the authors. battery, considering multiple life cycles with various 2nd and EoL applications, remains an Licensee MDPI, Basel, Switzerland. important, and yet an unanswered, question. This article is an open access article The aim of this paper is to demonstrate the advances of 2nd life applications for distributed under the terms and lithium ion batteries from electric vehicles based on their energy demand within various conditions of the Creative Commons multiple life cycles. The total impact of a product consists of multiple factors including Attribution (CC BY) license (https:// environmental, social and economic factors such as the production costs, supply and creativecommons.org/licenses/by/ demand, which are influenced, among other things, by the customers’ acceptance. This 4.0/). Sustainability 2021, 13, 5726. https://doi.org/10.3390/su13105726 https://www.mdpi.com/journal/sustainability Sustainability 2021, 13, x FOR PEER REVIEW 2 of 24 Sustainability 2021, 13, 5726 environmental, social and economic factors such as the production costs, supply 2and of 22 demand, which are influenced, among other things, by the customers’ acceptance. This study is based on the impact of the energy demand in order to present the potential of study2nd Life is based applications on the impact in a comprehensible of the energy demand way. 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