German powertrain supplier Vitesco Technologies, looking to become a greener company, is turning to green lasers to help it do just that.
Vitesco has adopted new laser technology developed by German laser producer Trumpf to help mass-produce battery management electronics for BMW Group, among other potential uses.
The green lasers stand in contrast to the typical infrared lasers used to manufacture copper-welded joints, which are part of the newly important battery management electronics used on electric vehicles.
But the lasers' properties are quite different, and by using green lasers for copper welded joints, the supplier is able to save energy and operate more efficiently, said Ricus Mueller, senior expert in manufacturing technology at Vitesco.
"It's the perfect laser for electronics applications," he said in an interview. "The green laser allows us to have cleaner processes — not only clean in an environmental point of view, but in a process point of view."
The key is in the difference in wavelengths between green lasers and infrared lasers.
According to Vitesco, the green lasers developed by Trumpf operate in the visible light spectrum with a wavelength of 515 nanometers. Traditional infrared lasers have a wavelength of 1,030 nanometers.
"That's a big difference," said Christian Goth, head of operations manufacturing technology in Vitesco's electrification solutions division. "Our main application for this is copper welding, and you have much, much better efficiency with that while using green lasers."
Infrared systems can be challenging to use because of how copper reacts to it. At first, copper reflects much of the energy being directed at it by the IR laser until it suddenly begins to heat up. At that specific point, the process produces copper "splatter," which can require complex measures to protect electronic systems, according to Vitesco.
The process also can be inefficient, Mueller said, and it requires a large amount of energy because of the amount of radiation that is reflected off the copper.
"That's the main obstacle in the welding of copper, this huge waste of energy," he said.
Because of its wavelength, a green laser is generally easier to control and reduces the amount of energy required in the welding process. Welding a component with a green laser system could reduce energy consumption by up to 20 percent, according to Vitesco.
"You don't have as much contamination. You don't see as much splatter with a green laser, and you have less CO2 consumption," Goth said.
Reducing energy usage has become a major priority for many suppliers in recent years as they adapt to higher energy costs, particularly in Europe, and as they look to reduce their carbon footprints. Suppliers have come under pressure to cut back on carbon emissions and to reexamine their energy usage if they hope to receive business, making Trumpf's systems even more appealing.
Mueller said green lasers are well-suited for electronics applications. The company uses green lasers to build battery management electronics for BMW, products the supplier deems "highly integrated and highly complex."
"It's more precise, so we can weld smaller parts more efficiently," Mueller said.
Vitesco ranks No. 26 on the Automotive News list of the world's top suppliers, with global sales to automakers of $9.5 billion in 2021.
