Durable and Reusable EV Battery Joints for Extreme Conditions

The transition to electrified transport is central to Sweden's sustainable mobility strategy. For heavy vehicles in areas such as mining, forestry and construction, the battery pack is exposed to extreme vibrations for long periods of time. This can lead to screw connections losing their clamping force, which in turn risks the structural integrity, tightness and safety of the battery pack.

At the same time, a circular economy requires that battery components can be disassembled and reassembled multiple times for service and remanufacturing. Today, there is a knowledge gap about how the mechanical properties of fasteners deteriorate after repeated tightening cycles, as previous research has primarily focused on the electrochemistry of batteries rather than their mechanics.

The DURECO (Durable and Reusable EV Battery Joints for Extreme Conditions) project aims to generate the knowledge required to design reliable and reusable bolted joints. Through experimental tests at the coupon level, we investigate how vibrations, fatigue and repeated reassembly affect the function of the joints.

The concrete goals of the project are to:

• Understand the consequences of long-term vibrations on clamping force.
• Map the degradation of mechanical joints after repeated disassembly and reassembly.
• Create a basis for future design guidelines for circular battery packs.

The results from DURECO are also expected to be applicable in other sectors, such as passenger car and truck design.