Lithium-ion Battery Mechanochemical approach to Recycling.

Before getting started we need to understand " Why is lithium so bad for the environment? " According to a report by Friends of the Earth (FoE), lithium extraction inevitably harms the soil and causes air contamination. As demand rises, the mining impacts are “increasingly affecting communities where this harmful extraction takes place, jeopardizing their access to water,” says the report. Similarly, Lithium mining does have an environmental impact, but it is no worse than oil drilling. This is especially true when you consider the carbon emissions produced from petroleum products during their usage, as compared to lithium-ion batteries that have little to no GHG emissions during their use. In fact, in 2016, the largest Lithium mining companies, as measured by CO2 emissions, were responsible for 211.3 million metric tonnes of carbon emissions in that year alone. Mining for lithium, like most metals, is a dirty business.

One a major part of everyday electronics like laptops, phones, and toys, lithium-ion batteries have now been tasked with larger roles of helping decarbonize transportation. Countries around the world are banking on battery-electric vehicles (BEVs) to reduce carbon emissions as they shift away from fossil fuel-powered cars. However, the large-scale use of lithium-ion batteries also presents a different problem of recycling. While other components of the battery, such as nickel, cobalt, copper, and aluminum, can still be recycled, lithium recycling itself isn't economically feasible, resulting in battery makers reaching out for more mined lithium than recycled one.

With their high energy density and working voltage, it’s hard to beat a lithium-ion battery. But current recycling needs temperatures of more than 1000°C, or corrosive chemicals, plus a lot of work sorting the batteries and excess waste before and after the lithium is extracted.

According to the researchers, it’s a “universal” method: it could work on any lithium-ion battery.

“This method is expected to increase efficiency at a large scale, foster environmental sustainability, and reduce the overall cost of the lithium-ion battery recycling process,” says Dr Oleksandr Dolotko, a researcher at the Karlsruhe Institute of Technology, Germany, and lead author on a paper describing the research, published in Communications Chemistry.

“Currently, we achieved up to 70% of lithium recovery on the laboratory scale.”

This New lithium-ion battery recycling method that’s energy efficient and needs no added chemicals. The method employs “mechanochemistry”: using mechanical energy to prompt a chemical reaction. Grinding the reagents in a ball mill is a common way of doing this.

“Mechanical treatment (or ball milling) is already used in battery recycling technologies, but only for crushing electrodes during the ‘black mass’ preparation,” says Dolotko. (The ‘black mass’ is what batteries are processed into before recycling.)“We believe that until now, the ability of mechanochemistry is not used in recycling technologies to its full potential.”

The lithium in lithium-ion batteries is bonded to oxygen, and a variety of different metals like cobalt, manganese, nickel, and iron. Herein we report a highly efficient mechanochemically induced acid-free process for recycling Li from cathode materials of different chemistries such as LiCoO2, LiMn2O4, Li(CoNiMn)O2, and LiFePO4. The introduced technology uses Al as a reducing agent in the mechanochemical reaction. Two different processes have been developed to regenerate lithium and transform it into pure Li2CO3. The mechanisms of mechanochemical transformation, aqueous leaching, and lithium purification were investigated. The presented technology achieves a recovery rate for Li of up to 70% without applying any corrosive leachates or utilizing high temperatures.