A research team led by Graz University of Technology (TU Graz) has developed new EV battery design guidelines aimed at improving safety, repairability and sustainability across the battery life cycle.
The E-Track project, which features researchers from the Vehicle Safety Institute at TU Graz, together with the Institute of Environmental Systems Science at the University of Graz and industry partners, has highlighted a lack of uniform design standards as a barrier to the repair and recycling of EV batteries, while also making it more difficult for emergency response teams to handle damaged or burning batteries safely.
‘Major challenges’
“Without uniform design standards, emergency services often face major challenges in an emergency because the structure and behaviour of battery systems are difficult to assess,” commented Markus Fasching, project manager, Vehicle Safety Institute at TU Graz. “At the same time, we lose valuable resources if batteries cannot be repaired or fully recycled.
“Our work shows that safety, efficiency and recyclability can be improved together through well thought-out design.”
About the research
In undertaking their research, the team compared conventional bonded battery housings using thermally conductive pastes with two alternative designs. One of these used replaceable housing covers and heat-dissipation pads, while the other used electrically insulating oil for cooling, and a screwed, sealed housing.
As they noted, the latter approach ‘facilitates disassembly and enables the targeted replacement of individual cells’.
With battery cells accounting for around three quarters of the total mass of batteries, their re-use is ‘crucial for the ecological and economic balance’, the researchers added. Life-cycle analysis indicated that repair-friendly designs become worthwhile when at least 8% of the cells can be reused.
The researchers also developed diagnostic methods based on electrochemical impedance spectroscopy, paired with virtual multi-physical models, which make it possible to identify internal damage such as micro-shorts that could potentially result in critical events such as battery fires.
As they noted, while these guidelines were primarily developed for electric two-wheel vehicles, the methods and simulation processes applied could also be directly transferred to larger electric vehicle classes such as cars and lorries.
‘The results of E-Track thus create a sound basis for future industrial standards and could also serve as a starting point for regulatory frameworks,’ the researchers said. Read more here.
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