Heating not shredding: German battery recycling research

When it comes to battery recycling, many research institutes and companies rely on mechanical treatment: lithium-ion batteries are shredded to obtain “black mass,” which contains valuable materials such as lithium and cobalt. To prevent spent batteries catching fire, they are discharged beforehand, but that is not always possible.
“The spontaneous and uncontrolled release of energy, also known as thermal runaway, represents one of the greatest challenges,” said Fabian Herz, professor of apparatus and systems engineering at Anhalt University of Applied Sciences. That is why he and his team are researching how power storage units can be thermally separated into individual components in a furnace reactor. The research project is funded by the European Union and the German state of Saxony-Anhalt.
Separation place in rotary kilns up to six meters long and one meter in diameter, on the university’s Köthen campus. Temperatures of up to 1,600 C are reached during the process before researchers and partner organizations assess the extent to which components separated in that manner are suitable for further processing and reuse. The aim is to upscale the process with industrial partners but the researchers will first need to make the separation method less energy-intensive.
Pioneers
“Our goal is an efficient process in a furnace reactor that achieves the highest possible recovery rate for the black mass,” said Herz. The process should be applicable to batteries’ most important components – including from storage devices used in e-cigarettes, smartphones, and laptops, which contain such small amounts of valuable metals they cannot be recovered economically using conventional recycling methods.
Interest in lithium battery recycling is growing. The number of used lithium-ion batteries will increase many times over in the coming years, along with the need for new devices. Current EU battery regulation stipulates much higher recycling rates than in the past, in order for the bloc to become less dependent on imported raw material.
“That’s why we are not the only ones researching an efficient process,” said Herz, before adding, “however, we are pioneers in the thermal area.”
From pv magazine Deutschland.