From NMC to NMC – Challenges of Direct Recycling
Authors: Winkowska-Struzik Magdalena , Buchberger Dominika , Uhrynowski Witold , Struzik Michal , Boczar Maciej , Rogulski Zbigniew , Czerwinski Andrzej 
Published: December 2024

Since 1991, when SONY introduced lithium-ion batteries, we have been living in a "portable era". Today, we are surrounded by small mobile devices like laptops, cellphones, smartwatches, ear pods, and power banks. In 2021, EVs constituted almost 9% of the total automotive market share worldwide 1. EV sales in Europe have increased by 70% with 2.3 million cars sold, thanks to a new regulation mandating 100% CO2 emission reduction for new cars and vans from January 1st, 2035 2. Several automakers, including Volkswagen, Ford, and Toyota, have announced plans to electrify at least 50% of their fleets by the end of this decade. Before electric cars become feasible, we need to develop efficient recycling methods for spent batteries. Accumulating battery waste is unsustainable.
The battery industry faces challenges like rising material costs and geopolitical factors, such as ore mining in the Central African Copper Belt and the recovery of raw critical materials 3. Efficient resource management is a top priority in the European Union, with both EU Parliament regulations and grassroots initiatives like 6R being widely implemented. Recycling of lithium-ion batteries involves the recovery of valuable metals such as cobalt, nickel, and lithium. There are two main methods for recycling: pyrometallurgical (heat treatment and smelting) and hydrometallurgical (acid leaching, bioleaching, solvent extraction, chemical precipitation, and electrochemical processes). Direct recycling is a cost-effective method that aims to restore the capacity and property losses of active materials through cycling. Recovered cathode material can be restored to its original performance by re-lithiation or upcycling into a modern composition, such as turning LCO into NMC 4,5. Solid-state sintering is the simplest method for direct recycling, however, a universal protocol for all cathodes is not available. Therefore, distinct healing chains for each active cathode must be established before being applied to mixed cathodes and optimized.
In my upcoming presentation, I will discuss a novel method for recycling LiNiMnCoO2, a significant battery waste material. We have developed an environmentally friendly technology that can extract lithium from degraded NMC powders, that can be further lithiated and reused as active electrode powder, while the extracted lithium can then be converted into hydroxide or carbonate and reused as a precursor for the synthesis of fresh NMC or recycled NMC precursors. The performance of resynthesized materials will be presented and discussed.

The authors would like to acknowledge the Initiative Excellence Research University of University of Warsaw for financially supporting this work.

1. L. Paoli and T. Gül, IEA, Paris (2022) https://www.iea.org/commentaries/electric-cars-fend-off-supply-challenges-to-more-than-double-global-sales.
2. European Commission, European Green Deal (2021).
3. European Commision, Study on the review of the list of Critical Raw Materials: executive summary (2014, 2017, 2020)
4. T. Yang et al., Adv Sustain Syst, 4 (2020).
5. L. Gaines, Q. Dai, J. T. Vaughey, and S. Gillard, Recycling, 6 (2021).