The Eurecat technology centre is coordinating the European Marbel project which has developed a new electric vehicle battery concept based on the principles of modularity and the potential for large-scale recyclability with a view to lessening environmental impact and unlocking the circular economy in the automotive industry.
In Catalonia, alongside Eurecat the project has involved the Catalonia Energy Research Institute (IREC) and Applus+ IDIADA, FICOSA and OTC Engineering.
Eco-design of the prototypes has targeted easy assembly and disassembly of the battery components to have a direct impact on the efficiency of their repair, reuse in other applications and recycling. To this end, the project has included up to 60 percent post-consumer recycled aluminium, which saves up to 777 kg of CO2 equivalent per battery box, and prioritised modularity to extend the service life of the battery and its components and thus reduce waste and its impact on the environment.
Other innovations have been introduced to support ultra-fast charging by implementing a cooling system design which ensures uniform heat removal from the cells and busbars coupled with optimisation algorithms for the charging process. A junction box has also been fitted which allows the battery architecture to be switched from 400V to 800V and vice versa as needed and can be used for batteries in a range of sizes.
“The circularity approach creates a pathway towards more sustainable electric vehicle technology,” says Eduard Piqueras, MARBEL Project Coordinator and European Programmes Manager at Eurecat. “Plus by optimising battery performance we address the main hurdles hindering electric car acceptance and uptake such as limited range and lengthy charging times, enabling longer trips.”
Second life for batteries
One of the key factors addressed by the project is the second life of batteries which enables reuse and reconditioning of battery components for energy applications other than in the automotive industry.
“By tapping eco-design principles such as modularity, second-life applications and materials with a high percentage of recycled content and high recyclability potential, Marbel extends battery life and material flows to cut waste while maintaining the value of the materials and making headway in sustainability and economic viability,” adds Violeta Vargas, a researcher in Eurecat’s Waste, Energy and Environmental Impact Unit.
Being able to separate the components more easily also “increases the reparability of the battery and, consequently, its useful life, since it is possible to disassemble it easily down to the cell level and reassemble it just as easily,” explains Toni Lara, a researcher in Eurecat’s Product Innovation and Multiphysics Simulation Unit.
Marbel has also implemented advanced material recovery strategies to recover high-purity graphite, lithium, nickel, manganese and cobalt from the cells at the end of their service life in compliance with the European “Sustainability Rules for Batteries and Waste Batteries” Regulation.
Smart architecture
The prototypes feature smart architecture which combines busbar power connections that can be easily assembled and disassembled using standard bolted fasteners. Their flexible formats have been honed to simplify assembly operations and enable them to withstand potential vibrations in the vehicle’s battery pack.
The Battery Management System (BMS) also features wireless communications and smart real-time energy monitoring, significantly reducing weight, cost and design complexity. Specifically, a smart electronic device (iSCM, Smart Cell Manager) has been designed to be built into each battery cell, allowing local monitoring of each one and direct communication with the BMS via Bluetooth wireless technology.
This shortens the wiring of a 16-cell battery pack, for example, from more than 20 metres to just 80 centimetres, reducing material costs, weight and assembly complexity.
Data compiled by the BMS and information generated by the iSCM are fed into a digital twin system driven by artificial intelligence and machine learning algorithms that performs predictive analytics by combining multiple data sources in a single web-based application. The system can predict factors including remaining battery service life, state of charge and health and estimate when the battery will reach the end of its lifespan. This furnishes reliable information for planning a second service life on the basis of the components’ state of health.
The project has an €11 million budget and is funded by the European Union’s Horizon 2020 programme. The Marbel consortium has brought together 16 partners across eight European countries, including six universities and research centres, an automotive engineering company, two SMEs, an OEM and five component manufacturers.
