Fraunhofer tests disassembly of disused electric car batteries with robots

In the DeMoBat research project, the Fraunhofer Institute for Manufacturing Engineering and Automation (IPA) is testing how old electric car batteries and electric motors can be automatically dismantled with the help of robots. One of the aims of the research project itself is to investigate how battery systems from electric cars can be recycled in such a way that it is economically viable.

At present, old battery modules from electric cars are often shredded. To achieve a sustainable circular economy, they should be reprocessed. This requires all electric car batteries to be dismantled. Disassembling them into their individual components is a prerequisite for reusing components.

Dismantling the batteries by hand is very time-consuming. This requires specialized and time-consuming skilled workers who can handle high-voltage technology. The work is also hazardous to health due to the high voltages and dangerous gases. In addition, dismantling by hand takes a long time and incurs high costs, which makes remanufacturing less worthwhile.

The researchers at Fraunhofer IPA have therefore set up a test facility - the largest in Europe, as they say - to largely automate the dismantling process using robots. The scientists have set up eight techniques for demonstration and testing.

Automatic dismantling of a battery

These include a robot from the robotics company Kuka. The six-axis KR Quantec industrial robot arm can lift around 270 kg, but is used for more delicate but torque-heavy work during disassembly. For example, it loosens screws, opens sealing joints and disconnects cables.

The problem with battery disassembly, however, is that there are numerous different battery designs that vary not only from manufacturer to manufacturer, but also within the manufacturer. The robot must therefore be able to adapt to these different variants. This is ensured by the Pitasc software developed by Fraunhofer IPA. Using image processing systems, the robot recognizes the respective battery model and can derive the individual components from this. It also uses image processing to independently recognize the position of screws, for example, so it does not need to be trained for each disassembly step. After each disassembly step, the Kuka robot uses 3D cameras and sensors to check the status.

But the Kuka robot and the scientists also have to contend with other adversities. The batteries are constantly being further developed, and their structure is changing as a result. And they are designed to be very compact so that they can be accommodated in vehicles to save space. Increasingly, screw connections are being dispensed with in favor of bonding. However, bonding is more difficult to remove with a robot than screwing. However, the Fraunhofer IPA claims to have found ways of dealing with the varying position of cables in the batteries.

(olb)