SK Innovation battery recycling tech wins US nod
SK Innovation’s (SKI) battery recycling technology has been verified by Argonne National Laboratory, a research institute under the US Department of Energy, the South Korean company said on March 29.
According to SKI, the technology extracts metals inside used-up lithium-ion batteries for electric vehicles (EV). Lithium retrieved with this technology emits 74 per cent and 41 per cent less greenhouse emissions compared to that produced from mines and salt lakes, respectively, according to Argonne National Laboratory’s life cycle assessment on SKI’s technology.
“This technology will allow us to respond flexibly to global environmental regulations,” said Lee Sung-joon, director of SK Innovation’s Environment Science Technology Center. When lithium is mined at high temperatures, the process emits a great amount of pollutants to the atmosphere including sulphur oxide.
Existing recycling technologies first retrieve other metals – such as nickel, cobalt and manganese – then extract lithium after. In this process, lithium is adulterated. However, SKI’s technology takes out lithium first and foremost to maintain its purity.
An SKI official said: “Typical recycling technologies recover lithium in the form of lithium carbonate, which is inadequate to reuse for high-nickel batteries. However, SKI’s technology extracts lithium directly in the form of lithium hydroxide, which is suitable for manufacturing high-nickel batteries.”
To manufacture high-nickel batteries, lithium hydroxide is essential, the official added. The melting point of lithium carbonate is 723 degrees Celsius. However, the manufacturing process of high-nickel batteries doesn’t go up as high as 723 C, which is why high-nickel batteries require lithium hydroxide, which melts at 462 C.
Also, extracting lithium directly in the form of lithium hydroxide can cut costs significantly. Typically, lithium hydroxide is produced by adding catalysts to carbon and letting them react with each other. This additional process drives up the price of lithium hydroxide by about $1 to $2 per kilogramme.
The technology is the latest development under a partnership with Hyundai Motor Group, according to SKI.
In September, SKI signed an agreement with Hyundai Motor and its sister company Kia to together develop an EV battery ecosystem including the reuse and recycling of EV batteries.
However, SKI said immediate commercialisation of the technology is unlikely.
“The technology will have to wait as there are insufficient amount of used-up EV batteries in the market and not enough battery recycling infrastructure in Korea,” the SKI official said.
Argonne National Laboratory evaluated SKI’s technology based on a model called GREET, short for greenhouse gases, regulated emissions and energy use in technologies. The model, developed with funding by the US energy department, can analyse the life cycle of EV batteries in detail.
Based on the model, Argonne National Laboratory has conducted environmental assessments on global automakers and energy companies including General Motor, Ford, Chrysler, ExxonMobil, Shell and BP. The US state of California is expected to utilise the model to draw up its carbon regulations for automobiles.