Inspection and Evaluation Method to Repurpose Used Batteries

Abstract

This Master’s Thesis presents a comprehensive study on the inspection and evaluation method for repurposing used batteries. Focusing on the transition from serving its first life in an electric vehicle (EV) to becoming a part of a Battery Energy Storage System (BESS). The research addresses the need for a standardized and scalable evaluation method, in order to ensure safe and effective utilization of second-life batteries (SLB). By leveraging insights from the batteries first life, performance requirements for BESS applications, and existing industry practices, the thesis proposes a structured evaluation process. Through a combination of background study, literature review, empirical studies, and interviews with industry stakeholders, the thesis identifies key factors in developing an efficient evaluation method for repurposing used batteries. The results highlight the challenges and opportunities in the current industry practices, emphasizing the importance of established policies and regulatory standards in enabling successful battery repurposing. The proposed evaluation method is presented using the IDEF0 modeling methodology, and consists of four major activities. The activities are referred to as visual inspection and safety evaluation, first screening, diagnostic packages, and finally classification and BESS matching. The findings of the research study contribute to advancing the field of battery repurposing by providing a practical framework for stakeholders in the automotive industry, remanufacturers, and energy utility suppliers. The proposed evaluation method offers a systematic and comprehensive approach to repurposing used batteries, facilitating the transition towards a circular economy and sustainable energy solutions. The findings and recommendations presented in this thesis serve as a valuable guide for enhancing current practices in battery repurposing and promoting the generalization of the results. The findings of this study will serve as a guideline for the sorting, grading, and assessment of retired flat and cubic batteries from EVs, as well as demonstrate the technical feasibility of how to grade and repurpose retired batteries for two different types of BESS applications.