On the roads, there are more and more electric vehicles reputed to be less polluting than their thermal counterparts. But this does not prevent the environmental impact of their batteries from posing a real problem. It is becoming urgent to find recycling solutions. And this is exactly what the European company Northvolt is working on.
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[EN VIDÉO] In 2050, our everyday objects will be recyclable Due to excess waste and a shortage of raw materials, and in a context of increasing global consumption, the total recyclability of our everyday objects will become an obligation in the future. Everything will have to be removable and the components will be able to start again in a circular economy. This salutary development has already begun, as this episode of Dreaming of the Future, broadcast this evening on the Planète + channel, explains.
On the road, electric cars emit less CO2 than their thermal counterparts. However, the lithium-ion batteries found today in all these vehicles have a significant environmental impact. Because they use non-renewable resources and because at the end of their life, they can pollute the soil. In Germany since 2017 already, manufacturers must offer a “reasonable and free” solution to return used batteries to “close proximity” to the place where they were sold. Obligation whose non-respect recently earned Tesla a fine of no less than 12 million euros!
Meanwhile, the Northvolt company, founded in 2016 by two Tesla alumni, continues on its way. It is currently building the largest battery factory in Europe in Sweden. A factory intended to produce the equivalent of 32 GWh of capacity per year and thus to compete with the “giga-factory” of the American manufacturer. If Northvolt has chosen Sweden, the north-west of Sweden, it is for its proximity to raw material deposits (nickel, cobalt, lithium and graphite). For its long experience in recycling too.
Because according to Northvolt, 30% of greenhouse gas emissions attributable to an electric car battery come from the extraction and refining of raw materials. Thus recovering these raw materials from used batteries and reusing them in new batteries – up to 50% initially – could greatly improve their carbon footprint.
A process still to be improved
Since last summer, a pilot recycling plant has been testing the processes devised by Northvolt engineers. And it is not easy. The first step is to repatriate electric car batteries – full of toxic and flammable chemicals – safely. Then, they must be dismantled and unloaded. Because only a complete discharge can limit the risks of thermal runaway which can lead to an explosion. Northvolt is working to automate this part of the process, but there are so many different battery designs out there that again, it’s not that easy.
After disassembly, the goal is to crush the cells in a vacuum to prevent reactive gases – carbon dioxide or oxygen – from contaminating the materials. These are then sorted mechanically and magnetically and then delivered for some – copper and aluminum, for example – to nearby recycling facilities. The liquid electrolyte, on the other hand, is evaporated and condensed for later use.
too slow and too complex
All that remains is a sort of black powder which ultimately contains the most “precious” materials: nickel, manganese, cobalt, lithium hydroxide and graphite. Hydrometallurgical treatment – supplied by low-carbon hydroelectricity – in an acid bath allows them to be recovered. For now, the whole process remains too slow and complex to be economically profitable. But Northvolt hopes to improve it. And eventually, plans to build a recycling plant next to its giga-factory for manufacturing batteries from 2022.
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