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Where to go with the old batteries?
The registration numbers of electric cars are rising sharply. But where to go with the old propulsion batteries? The import association Auto-Schweiz aims for a recycling solution for the industry. Empa specialists support him.
Crunching, the serrated metal roller eats into the battery modules, crushes the plastic frames, slits open the silver foils of the lithium polymer packs, shreds everything into small pieces. In the end, a fine powder remains. If you throw it in succession into several acid baths, then salts and oxides are formed, from which new traction batteries can be built. The YouTube movie "New Recycling Method for Batteries from Electric Cars", released in May 2019, shows something that until recently could not be seen: the shredding of lithium-ion batteries. These batteries are usually flammable. A little bit of electrical tension, a spark is enough, and all the material goes up in flames. The German company Duesenfeld therefore completely discharges the batteries and floods the hermetically sealed shredder with nitrogen. The combustible electrolyte liquid is vaporized and pumped out before the powder is removed. In this way, 96 percent of all materials are recyclable.
Some 40 000 electric cars and plug-in hybrids with lithium-ion batteries are currently driving on Swiss roads - just under one percent of the entire vehicle fleet. But it will be more quickly. In the first three months of the year 2019, the share of new registrations already increased to 5,3 percent.
And that's just the beginning: a whole range of powerful electric cars will be launched this year: Audi e-tron, Mercedes EQC, Peugeot e-208. You will encounter the Tesla Model 3, which has been reporting approval statistics since March. 2020 will offer the VW Group its first mass-produced electric automobile, the VW iD.3. So it's high time to think about what happens to the traction batteries, if these cars get damaged or scrapped at the end of their lives.
Recycling system of car importers
The association Auto-Schweiz, which represents most Swiss car importers, is aware of this. 2018, the car importers therefore turned to Empa to determine the cornerstones of a recycling system for traction batteries. For example, Empa had previously advised Swico, which deals with the recycling of electronic equipment and computer technology. But unlike electronic products, no advance recycling fee (vRB) has been charged for cars so far. The Auto-Schweiz association is aiming for an industry solution and has commissioned the foundation Auto-Recycling Schweiz, which has been taking care of the dismantling and recycling of Swiss end-of-life vehicles since 1992. The Empa researcher Rolf Widmer and his colleagues from the "Technology and Society" department have been working together with the Auto-Recycling Foundation on this project since March. They analyze recycling systems in neighboring countries, examine the costs and the ecological footprint and make model calculations in order to estimate the future accumulation of old batteries and recommend the appropriate strategy.
Use hot or cold?
Most lithium-ion batteries are not previously shredded cold, as in the aforementioned method of Duesenfeld, but burned in an oven and then ground. The market leader is the Belgian company Umicore. During hot utilization, the thin copper foils melt the battery and, together with cobalt and nickel, form an alloy that can be recycled. However, the lithium, graphite, liquid electrolyte and aluminum in the battery burn and end up in the slag. They are lost for economic reuse.
In addition to the hot Umicore recovery and the cold shredding under inert gas, there are, however, other automated Zerlegemethoden. Batrec Industrie AG, a Swiss battery recycling specialist, shreds some batteries in a wet environment to avoid fires. The Empa experts will compare all these methods.
The transport problem
However, finding the best recycling system is not just about shredding by itself, but also about building a supply chain. "Traction batteries of accident vehicles can burn suddenly and must now be transported as dangerous goods in special containers," explains Daniel Christen, Managing Director of the Foundation Auto-Recycling Switzerland. "It's time-consuming and expensive". Christians are looking for a better solution to "defuse" batteries and deliver them to waste disposal.
Approaches are already in place: the company Blubox Trading AG in Birrwil, for example, imports the "Firebox" from a Dutch manufacturer. The Firebox is a cargo container with a built-in fire extinguisher that can hold a whole car or a larger load of not yet "defused" batteries.
And last but not least, freight forwarders and car recyclers must be trained so that old electric cars are not dangerous. Already today, there is a database for rescue services, which provides exactly this information: On a tablet, the firefighter enters the number of the control plate and learns whether he has an electric car in front of him and how he must disconnect the battery from the power grid of the car. With the same information, electric cars could be disassembled in a safe way.
Many questions are still open
Nonetheless, many open questions remain that need to be answered before setting up a recycling system. How is the market for used traction batteries developing? Will it be worthwhile once to provide battery packs with new modules and put them back on sale - similar to replacement engines or gearboxes? Or can drive batteries become stationary solar energy storage devices in a "second life"? So maybe the big wave of used batteries will be delayed at the recycling companies? Does Switzerland need any large recycling capacity at all, or will the (foreign) car manufacturers collect most of the traction batteries and use them themselves? Much will depend on the market prices of raw materials, the price of lithium, cobalt, nickel and graphite, the price and performance of new batteries, but also the policy that sets the framework and rules.
Anyway, the good news is: electric cars are not a recycling problem. For all steps of the recycling process, technical solutions are emerging. And a number of specialists are already working to put these solutions into practice.
Scientific contact:
Dr. Rolf Widmer
Empa, Technology and Society
Tel. +41 58 765 78 63
[email protected]
Rainer Klose Communication
Empa - Federal Materials Testing and Research Institute
Further information:
https://www.empa.ch/web/s604/battery-recycling
Source: text and image of IDW
