BATTERIES AS A RAW MATERIAL

A common reservation about electric vehicles is that the batteries are so hard to recycle. Nickelhütte Aue shows how it’s done

Blocks of copper shavings are stacked in the production hall. They glint and sparkle in the sunlight on this late summer day. These precious-looking blocks of material were made by pressing copper recovered from waste cables. We encountered the copper blocks at Nickelhütte Aue in the Erzge-birge (Ore Mountains). “We work with non-ferrous metals,” says Managing Director Henry Sobieraj. Salvaging is the main business activity. This could be considered an understatement, since the company founded in 1635 is one of Germany’s largest recycling companies with annual turnover of 250 million euros. The company is working on transforming the Erzgebirge’s mining tradition, adapting to the circum-stances of the 21st century. No longer are miners digging ore in the mines and transporting it to Aue. Copper and especially cobalt and nickel are now obtained through recycling, for example, from used lithium-ion batteries such as those in electric vehicles.

Some lithium-ion batteries now contain about 15 per cent nickel

While the raw materials used to be extracted from mineral resources, what are known as secondary materials are now becoming increasingly important. “That may sound second-rate, but it’s really not. Quite to the contrary,” Sobieraj says. Recycled raw materials are sustainable and the reduction in CO2 emissions is considerable. Mining is much more costly: “Ore may contain 0.5 per cent of the raw material you are after. Therefore, 99.5 per cent has to be transported back into the mountain.” That costs money, it takes machinery and consumes energy. Some lithium-ion batteries now contain around 15 per cent nickel: “You won’t ever find ore contai-ning that much nickel,” Sobieraj tells us. The concentration of the valuable metal is much higher and it already exists in its metallic form. Which is why numerous pallets of grey, fireproof steel con-tainers are stacked in the warehouse at Nickelhütte Aue. They are filled with lithium-ion vehicle batteries. The batteries come from prototype test centres or returns from new battery production. “We don’t always know what we’ll be dealing with,” says Michael Neumann, Head of Research and Development. For instance, whether the batteries are damaged. Employees remove the batteries from the containers one by one, disassemble them and place the components containing metal onto a conveyor belt. It goes up toward a large pipe that is tilted downward and slowly rotates. A furnace inside the pipe produces high temperatures, starting the smelting process. That among other things produces what is known as black mass. Rather than dark matter, it’s a ni-ckel-cobalt-manganese compound. Using a combination of a pyrometallurgical and hydrometallurgi-cal method, Nickelhütte Aue dissolves the materials it contains and recovers them, for example, as nickel sulphate, cobalt sulphate and copper sulphate. The batteries also contain valuable lithium, albeit only at three per cent. How to best recycle that is the subject of ongoing research by the chemists and engineers in Aue. Initial results have been obtained already in the form of lithium car-bonate. However, the white powder with a consistency in between sugar and flour is not being pro-duced in larger quantities yet. “We’re working on it,” says Neumann. Making this material available for new battery production as well is the goal. Nickelhütte Aue recycles 4000 tons of lithium-ion batteries a year and its reported capacity is 10,000 tons annually. Since the number of electric vehicles on the road increases every day, the company in the Erzgebirge is optimistic that this capacity will soon be fully utilised. Slightly over eight milli-on new electric vehicles are projected to be licensed in Western Europe in 2030 alone. The operation is not limited to a second life for defective lithium-ion batteries, however. 485 employees at the plant process around 90,000 tons of scrap and waste containing non-ferrous metals per year, including about 5000 tons of nickel, 250 tons of cobalt, 12,000 tons of copper and 20,000 tons of aluminium. “Basically, nothing is left over that would have to go into a landfill,” says Managing Director So-bieraj. “The slag produced by the pyrometallurgical process is used in road construction.”

Large cones of slag are seen on the company premises where they are left to cool. It looks as though giant, environmentally conscious “Räuchermännchen” (incense smoker in the shape of a figurine) had stored their mammoth incense cones here. The centuries-old mining tradition of the Erzgebirge is reflected by the greeting “Glück auf” (good luck) exchanged by all the employees – even those starting the early shift at 5:45 am. And by the administrative building that dates back to the East Germany era. An iron “Schwibbogen” (candle arch) depicting workers, with eight lights, is mounted over the door. It reflects the factory’s long history: The site was home to a blue dye plant in 1635. Copper and especially cobalt ore was also found here by miners in the 17th century. A dye containing blue pigments was made from this in Aue. This was henceforth used by painters in the production of Delftware and Meissen porcelain to decorate prized tiles, plates and vases.

Nickel salts and electrolyte nickel were produced in Aue during the East Germany era

Cobalt mining in the Erzgebirge stopped a long time ago as synthetic and therefore much cheaper ultramarine replaced cobalt blue in the 19th century. To survive, the plant in Aue had to reinvent itself and primarily produced nickel from the available ore starting around the year 1850. It was first used in the production of low-cost tableware made of nickel silver and later mainly in steel refining. Nickel salts and electrolyte nickel were produced in Aue during the East Germany era. These are used in stainless steel alloys and corrosion protection. Managing Director Sobieraj, a native of Freital who has been with the company since 1996, is fasci-nated by the plant’s recurring transformations over the centuries. “Of course I wasn’t there in 1635, and it’s a long way from cobalt blue to lithium-ion batteries. But it’s fair to say that something new happens every year.” Skilled employees are essential to ensure that this story continues. The frequently bemoaned shor-tage of skilled workers is an issue in the Erzgebirge, “but not as big a problem at Nickelhütte Aue,” Sobieraj says. There are two reasons for that, one being that the company is a well-known and good employer. The operation has won awards such as “Employer of the Future” and the Germany Sustainability Prize. Natives of the Erzgebirge are also firmly rooted in the region and not as likely to leave. Yet the competition for employees is becoming fiercer here as well. “The number of people in the Erzgebirge region retiring each year is twice that of people entering the workforce.” It’s not hard to figure out that soon there won’t be many left. “We need people coming in from outside the region,” Sobieraj says. After all, Nickelhütte Aue wants to carry on for at least another 400 years.

By Mirjam Hauck, Süddeutsche Zeitung