High-Performance Recovery of Cobalt and Nickel from the Cathode Materials of NMC Type Li-Ion Battery by Complexation-Assisted Solvent Extraction

Cradle to gate life-cycle assessment of battery grade nickel sulphate production through high-pressure acid leaching

The rising global demand for high-purity nickel (Ni) sulphate, primarily used in lithium-ion batteries, is largely met by processing Indonesian laterite ores via hydrometallurgy. However, this supply chain is associated with significant environmental challenges and lack of transparent industrial data. This study uses a cradle-to-gate life cycle assessment (LCA) approach to quantify the greenhouse gas (GHG) emissions and energy use associated with the production of mixed hydroxide precipitate (MHP) from low-grade Indonesian laterites via high-pressure acid leaching (HPAL), which is then refined in China for the production of battery-grade nickel sulphate hexahydrate (NiSO4·6H2O, NSH). Fifteen impact categories are analyzed using established impact assessment and allocation (mass and economic) methods. The analysis reveals that feed preparation/HPAL and purification are the stages that contribute most to environmental impacts and in particular to global warming potential (GWP). Mass allocation results in higher environmental impacts, with 36.8 kg CO2-eq per 1 kg of Ni in NSH for GWP, compared to 33.8 kg CO2-eq per 1 kg of Ni in NSH when economic allocation is used. Sensitivity analysis shows a potential reduction (up to 13 %) in key impact categories if production of NSH is fully integrated in Indonesia or a greener electricity mix is used. Overall, our results indicate that the production of MHP in Indonesia and its refinement to NSH in China has a GWP about two times higher than the global average. Given the limited number of LCA studies for the production of battery-grade nickel, this study highlights major environmental concerns for the NSH production process from Indonesian laterites and identifies opportunities for improvement, towards a more sustainable global battery supply chain.

Fe3+ and Al3+ removal by phosphate and hydroxide precipitation from synthetic NMC Li-ion battery leach solution

The removal of trivalent iron and aluminum was studied from synthetic Li-ion battery leach solution by phosphate and hydroxide precipitation (pH 2.5-4.25, t = 3 h, T = 60 °C). Phosphate precipitation exhibited both crystal nucleation initiation (pH 2 vs. pH 3) as well as complete (~ 99%) Fe and Al removal at lower pH compared to hydroxide precipitation (pH 3 vs. 3.5). The precipitation time of phosphate was shorter (40 min) than that of hydroxide precipitation (80 min). At pH 4 the loss of valuable metals (Li, Ni, Co) in the precipitate was negligible in the phosphate cake, whereas in the hydroxide process the co-precipitation was 4-5% for Li, Ni and Co. The filtration rate of phosphate precipitate was shown to be significantly faster. The presence of fluoride did not have any notable effect on phosphate precipitation, whereas in hydroxide precipitation, it potentially had a negative effect on aluminum extraction.

Solvent Extraction for Separation of 99.9% Pure Cobalt and Recovery of Li, Ni, Fe, Cu, Al from Spent LIBs

In this work, hydrometallurgical recycling of metals from high-cobalt-content spent lithium-ion batteries (LIBs) from laptops was studied using precipitation and solvent extraction as alternative purification processes. Large amounts of cobalt (58% by weight), along with nickel (6.2%), manganese (3.06%) and lithium (6.09%) are present in LiCoO2 and Li2CoMn3O8 as prominent Co-rich phases of the electrode material. The pregnant leach solution (PLS) that was generated by leaching in the presence of 10% H2O2 using 50 g/L pulp density at 80 °C for 4 h contained 27.4 g/L Co, 3.21 g/L Ni, 1.59 g/L Mn and 3.60 g/L Li. The PLS was subjected to precipitation at various pH using 2 M NaOH but the purification performance was poor. To improve the separation of Mn and other impurities and in order to avoid the loss of cobalt and nickel, separation studies were carried out using a solvent extraction technique using di-(2-ethylhexyl) phosphoric acid (D2EHPA) and bis-(2,4,4-trimethylpentyl) phosphinic acid (Cyanex 272). Overall, this study examines the fundamentals of separating and synthesizing 99.9% pure Co sulfate from leach liquor of spent laptop LIBs with remarkably high cobalt content.

Solvent extraction for recycling of spent lithium-ion batteries

Up to now, solvent extraction not only recycle valuable metals (i.e., Ni, Co, Mn and Li) from the leach liquor of spent cathode materials, but also apply to treat spent electrolyte. This paper summarizes the development of solvent extraction in the field of recycling spent lithium-ion batteries (LIBs) from the aspects of principle, technology and industrialization. Meanwhile, the paper also comments on the challenges and opportunities for the solvent extraction facing in the recycling of spent LIBs.

Electric car battery: An overview on global demand, recycling and future approaches towards sustainability

Li-ion batteries are daily present in our electronic devices. These batteries are used in electric and hybrid vehicles supporting the current agreements to decrease greenhouse gas emissions. As a result, the electric vehicle demand has increased in the world. As Li-ion batteries are composed of critical metals in which there is a risk of interruption of supply in the medium term, recycling is the key to a sustainable future without internal combustion vehicles. Understanding the current scenario and future perspectives is important for strategies of new battery design, recycling routes and reverse logistics, as well as policies for sustainable development. This paper presents an overview of current and future vehicles used worldwide. An increase from 1.3 to 2 billion vehicles is expected worldwide until 2030; an outstanding demand will occur mainly in BRICS countries. The data demonstrated a correlation between the number of vehicles in use and GDP. Patents and processes designed for recycling Li-ion batteries and the new developments on pyro-, hydro-, and bio-metallurgical routes have been revised. The manuscript describes the importance and benefits of recycling as regards the supply of critical metals and future trends towards a circular economy.