CHARGING SYSTEMS / BUSBARS

RFSSW (Refill Friction Stir Spot Welding) and FSSW (Friction Stir Spot Welding) are used, among other applications, for aluminum-copper hybrid connections in the e-mobility. This is especially relevant when a large cross-sectional area of the joint is needed for low-resistance power transmission, as it is the case with charging systems or lithium-ion batteries in general.

When the positive and negative poles of lithium-ion batteries installed side by side in the battery tray need to be connected in series to increase voltage, FSW offers unique advantages. This is because the negative pole is often made of copper and the positive pole of aluminum, making them poorly connectable with fusion welding methods. By means of the FSSW technology it is possible to achieve a large cross-sectional area of the joint which means a better electrical conductivity of the connection. Electrical conductivity is of the utmost importance when it comes to the duration of charging and discharging of battery systems. Moreover, the growing e-mobility sector requires more and more fast charging systems, where FSSW contributes with its unique advantages.

Busbars are often used for power transmission and distribution in electrical systems such as electric vehicles. A major advantage is that they are flat and therefore more space-efficient than cylindrical cables. They are also easier to bend than cylindrical solid cross-sections and do not heat up as much due to their larger surface area. As a rule, these busbars are easier to install and require less maintenance than comparable conventional cables. This makes them an attractive option for electrical vehicles, but also for fast charging systems.

As the busbars are made of copper and aluminum, the RFSSW technology is ideal for producing reliable and robust connections of more complex parts.