Volvo was facing challenges with the treatment of the aluminium battery casing for their electric vehicles. Alro therefore developed a number of innovative technologies in which different assembly techniques play a crucial role.

The process we developed specifically for Volvo consists of several steps. First, it’s necessary to give the parts a KTL coating. Then specific pieces of certain parts need to be stripped. The coating process is followed by the assembly in several stages. Below is a description of each stage in the Volvo process.

• KTL coating

Volvo delivers the bare parts to Alro. The steel surface then goes through several successive steps: degreasing, application of an anti-corrosion coating, rinsing with deionised water, KTL coating, final rinsing and curing in a furnace.

• Laser stripping

Once we have applied the KTL coating, we need to remove or strip specific pieces of that coat on certain parts. For this Alro uses laser technology. A robot grabs the part and then moves it under a laser. This allows us to very accurately remove the coating from the electrical contact points.

• Assembly

Each part of the battery requires a different kind of assembly technique, which we perform at the different process stages. The operator places stickers, foam pads, rubber protection and felt on the necessary parts. A custom-made jig ensures accurate positioning.

More complex parts such as painted battery covers are assembled both automatically and manually. We follow several steps in the process for this:

• • Automatic assembly
    We take the coated battery covers to a robotic assembly cell. A multifunctional robot takes the parts from a rack and then places them in the correct application position.

• • Sealing
    Another robot applies sealant to the seams of the coated covers with extreme precision. Then these parts go into a furnace to cure the sealant. Afterwards, the parts are transported back to the robot cell.

• • Leakage test
    In the next step, we subject the sealed part to a leakage test. During the process, we put pressure on the covers for a predetermined time. If we do not find any pressure loss for a set time, the part goes to the manual assembly station.

• • Manual assembly
    The operator applies heat protection mats, protective foam pads, a sticker and a rubber seal. To ensure a perfect result, several lasers indicate where the operator needs to apply these parts.

• • Foam application
    After manual assembly, a portal handling unit applies a foam seal in several places. The foam seal is in preparation of the battery covers’ installation at Volvo. It ensures a perfect seal between the battery cover and the adjacent vehicle parts.

• • Quality control
    At the end of the process, we subject each part to thorough quality checks. This includes an automated camera check that makes sure all the parts have been assembled correctly. That is how Alro guarantees the best quality.

After the quality checks, the process is complete and all parts have the best possible corrosion protection. After that, all the parts are ready to be shipped to Volvo for further assembly. Alro Group is proudly helping to build the e-mobility of tomorrow thanks to robotisation and innovative, meticulous laser technology.