Lithium-ion battery (LIB) recycling plays a vital role in the circular economy by supporting a reliable and sustained supply of critical minerals. Commercial black mass, comprising cathode active materials and anodic graphite from spent LIBs, typically requires multiple energy-intensive steps for the recovery and regeneration of its critical minerals. Here, we report that a single-step microwave-induced plasma pre-treatment can lead to 85% selective Li recovery in water and ≈95% recovery of all transition metals in 1 M citric acid at room temperature. Of the various gas compositions evaluated, H2/N2 demonstrates the highest effectiveness. The synergistic action of H2 plasma, microwave coupling, and localized heating reduces the layered LIB cathode metal oxides to their metallic or lower-valence oxide forms, thereby enabling their facile extraction in green solvents. The residue consists of anodic graphite, which is regenerated through plasma treatment that reduces defects and decreases the interlayer spacing. The recovered graphite shows excellent efficiency as an LIB anode, surpassing commercial graphite in its activity. While here microwave plasma pretreatment has been explored for LIB recycling, it is a technological innovation that can serve as a versatile pretreatment step for hydrometallurgical extraction of critical minerals. r.

Recycling and utilization of cobalt, nickel, and manganese from black mass of spent Li-Ion batteries for supercapacitor applications

Comparative study on the leaching behavior of lithium-ion battery black mass using sulfuric and organic acids combined with hydrogen peroxide

The disposal of used rechargeable lithium-ion batteries (LIBs) has been an issue recently due to the increasing popularity of electrical vehicles to replace conventional gasoline-powered alternatives. Therefore, the development for an effective approach to reclaim the valuable minerals from used LIBs is critical. In this study, we demonstrate the use of electrophoresis to achieve desirable phase separation in the black mass derived from used LIBs. The black mass contains mixtures of graphite and lithium cobalt nickel manganese oxides (NMC). In a solvent, graphite and NMC exhibit distinct zeta potentials so they can be driven under an externally imposed electric field with different migration rates. Considering the phenomenon of gravity induced vertical sedimentation and electric field induced horizontal electrophoretic movement, we design an electrophoresis cell that enables physical separation of NMC and graphite. In addition, theoretic simulation has been conducted with parameters including material properties of graphite and NMC, as well as variables relevant to suspension formulations and electrophoresis actions. After electrophoretic separation using the cell designed from theoretical simulation, the analysis results (EDS and ICP) showed a significant increase in NMC content. This not only demonstrated the feasibility of electrophoretic separation but also verified the validity of our theoretical model. We believe that our electrophoresis driven phase separation technique provides a new opportunity for other mixtures containing suspending particles with different physical attributes.

Abstract The recycling of lithium-ion batteries (LIBs) is of critical importance due to the increasing demand for electric vehicles and portable electronic devices. It also helps address supply risks of critical raw materials and reduces the environmental impact of mining. Traditional recycling methods are often inefficient and environmentally damaging. This study investigates the use of deep eutectic solvents (DES), made from citric acid and choline chloride, for leaching valuable metals from black mass derived from spent LIBs. The research focuses on optimizing the leaching parameters, such as temperature, DES ratio, and solid-to-liquid ratio, to maximize the extraction efficiency of lithium, cobalt, nickel, and manganese. A key aspect of the study was the examination of the rheological properties of the DES system, as these properties significantly impact the leaching process. The viscosity and pH of the DES were measured, providing insights into their behavior under various conditions. Understanding the viscosity and flow characteristics of these DES systems is crucial for developing scalable and effective recycling methods. The DES mixture with a 2:1 ratio of citric acid to choline chloride, mixed with 50% water, showed the best performance. At 90 °C for 24 h, this DES mixture achieved leaching efficiencies of 77.5% for lithium, 79.9% for cobalt, 80% for manganese, 66.2% for nickel, 82.5% for copper, and 93.8% for aluminum. These findings suggest the potential of citric acid-choline chloride DES as a sustainable and environmentally friendly reagent for recycling LIBs.

The increasing demand for lithium-ion batteries (LIBs) is driving development of advanced recycling and refining methods. In this work, new cathode active materials are prepared from recycled lithium battery materials and subsequently electrochemically evaluated in coin cells. In detail, scrap LIBs were mechanically processed into a metal rich black mass, then reductive acid leached into an aqueous metal solution, and finally high-purity metal hydroxide precursor materials were prepared by selective electrochemical flow precipitation. Closed-loop LIB recycling into active electrode materials will enable US manufacturers to break their reliance on foreign sources of critical materials. For example, electroextraction process used here has potential to significantly reduce chemical & water use as compared to traditional metallurgic techniques. To this end, electroextracted materials refined from used batteries were collected and processed to be tested as precursor cathode active material (pCam).This study focuses on NMC 811 pCam. ICP-OES analysis confirmed the expected composition, although small amounts of sodium and copper were detected. To remove sodium, multiple water washings were performed, monitored by conductivity measurements. After drying, a two-step lithiation process was carried out using lithium hydroxide (LiOH) with varying lithium excess to compensate for potential losses during synthesis.X-ray diffraction (XRD) analysis confirmed a layered crystal structure with hexagonal symmetry (space group R-3m). The characteristic peak splitting of (006)/(102) and (108)/(110) was observed at 900°C in air, whereas under oxygen, this splitting occurred at a lower temperature of 750°C, indicating enhanced structural ordering. Additionally, oxygen atmosphere promoted better crystallinity, which is known to improve lithium-ion diffusion kinetics and cycling stability.Galvanostatic charge/discharge cycling at a C/10 and C/5 current rate were performed on half-cells within a voltage range of 3.0–4.2V. The material exhibits a first discharge capacity of around 225 mAh/g at C/10 current rate (Figure 1). The experimental conditions significantly influenced electrochemical performance. Samples synthesized in air exhibited limited specific discharge capacity due to incomplete lithiation and structural defects, whereas those synthesized under oxygen at an optimal lithiation temperature of 800°C demonstrated superior performance. A reaction time of 20 hours was required to achieve the highest specific discharge capacity of 185 mAh/g at C/5, with 90% retention after 80 cycles. Additionally, improved rate capability was observed for oxygen-treated samples, further confirming the beneficial effect of oxygen in stabilizing the layered structure.The improved electrochemical performance achieved under optimized conditions demonstrates the feasibility of using recycled materials for high-energy-density battery applications, contributing to the development of a circular economy in the battery industry. Figure 1

Lithium-ion batteries are essential to ensure electric mobility and reduce CO2 emissions from transportation. One of the most commonly used chemistries is nickel–cobalt–manganese (NMC) batteries, which also have applications beyond the automotive sector. The recycling of these batteries requires the development of technologies to enable the selective separation and recovery of the metals present in the battery. One of these selective technologies involves the use of deep eutectic solvents (DESs). This research study investigates the different parameters that influence the recovery of Co(II) from hydrochloric acid medium using the deep eutectic solvent 3 Aliquat 336:7 L-Menthol. Firstly, using synthetic Co(II) solutions, the parameters influencing the cobalt extraction process are examined, and then these optimal conditions are applied to the recovery of cobalt from solutions obtained by dissolving NMC 622 battery black mass in 10 M HCl. The obtained results show that the DES used is highly selective for Co(II) recovery compared to other metals present in the solution (Ni, Li and Mn), achieving recoveries of up to 90% of the cobalt initially present in solution. Stripping with H2SO4 0.5 M allows the recovery of cobalt as a crystalline monohydrate salt (CoSO4.H2O). The optimization of the Co/Cu separation conditions is carried out, achieving the separation of Cu(II) using Aliquat 336 in kerosene.

The rising demand for lithium-ion batteries (LIBs) highlights the urgent need for sustainable recycling technologies. Existing pyrometallurgy and hydrometallurgy methods can recover valuable metals but suffer from high energy costs and wastewater generation. Here, a selective flash Joule heating chlorination and oxidation (FJH-ClO) strategy is presented for the efficient separation of metals from spent batteries. In this process, cathode metals are first chlorinated for 60 s, after which the transition metal chlorides are oxidized to oxides, enabling lithium to be separated from transition metals due to their different aqueous solubility. This approach applies not only to the recovery of metals from lithium cobalt oxide (LCO), lithium iron phosphate (LFP), and lithium manganese iron phosphate (LMFP) cathode materials, but also to the anodic graphite, all from the black mass. The recovered graphite exhibits purity of ≈100% with a yield of 85%, Co at 99% purity and 97% yield, and Li at 99% purity with a 92% yield. Gram-scale experiments confirm the scalability of the method, maintaining high efficiency and selectivity. Life-cycle assessment and technoeconomic analysis reveal that the FJH-ClO process substantially reduces energy consumption, operation time, and reagent consumption, while lowering operating costs by up to 92%, compared to conventional approaches.

Enhancement of syngas production via plastic gasification in low-concentration CO2 by using spent lithium-ion batteries-derived black mass.

Recycling of NMC black mass from spent lithium-ion battery using supercritical fluid extraction.

Influence of boundary layer-cloud coupling on cloud microphysics based on aircraft observations in the North China plain.

Effect of graphite on selective lithium recovery from NCM-lithium battery black mass via hydrogen reduction.

Over the next 5–10 years, the feedstock to lithium-ion battery recycling facilities will shift from Co- and Ni-rich chemistries to lower-value battery chemistries, such as lithium iron phosphate (LFP). Traditional recycling processes use toxic and corrosive inorganic acids for leaching, generating toxic waste streams. The low-value feedstocks will be LFP-rich with contamination from lithium cobalt oxide (LCO) and lithium–nickel–manganese–cobalt oxide (NMC) battery chemistries. Overall, the lower-value feedstock coupled with the need to reduce environmentally damaging waste streams requires the development of robust, green leaching processes capable of selectively targeting the LFP and LCO/NMC battery chemistries. This research concluded that a first-stage oxalic acid leach could selectively extract Al, Li, and P from the industrially sourced LFP-rich black mass. When operating at the optimal conditions (0.5 M oxalic acid, 5% solids, pH 0.8, and an agitation speed of 600 rpm), >99% of the Li and P and >97% of the Al were selectively extracted after 2 h, while Mn, Fe, Cu, Ni, and Co extractions were kept relatively low, namely, at 19%, <3%, <1%, 0%, and 0%. This research also explored a second-stage leach to treat the first-stage leach residue using ascorbic acid, citric acid, and glycine. It was concluded that when leaching with glycine (30 g/L glycine, a temperature of 40 °C, an agitation speed of 600 rpm, and 2% solids at pH 9.6), that >97% of the Co, >77% of the Ni, and 41% of the Mn were extracted, while the co-extraction percentages of Cu, Fe, and Al were <27%, <4%, and <2%.

Reduction Roasting of Black Mass Recovered from NCM-based Spent Lithium-ion Batteries Using CH4 Gas

Liquidambar formosana Hance is one of the main afforestation species in Longquan Mountain Forest Park, where a large number of seedlings have recently been planted. In October 2024, leaf blight was observed on over 10% of 100 two-year-old seedlings (30°52′41.73″N, 104°21′33.85″E, 509 m). The disease initially appeared as marginal necrosis, especially at the leaf tips, accompanied by shrinkage and curling. Severe infections led to complete leaf necrosis, with conidiomata forming on the upper surface of affected tissues. Five symptomatic leaves were randomly collected from different trees. From these, five fungal isolates were obtained by single-conidium isolation (Chomnunti et al. 2014) and cultured on PDA. The colonies showed consistent morphology: entire margin, smooth, dense, abundant aerial mycelium, white on the obverse and white to pale yellow on the reverse, conidiomata semi-immersed or mostly immersed, exudating black conidial masses. The conidia on PDA were fusiform to ellipsoid, straight or slightly curved, with 4 septate, measuring 19-27.5 × 7-10.5 μm (x̄ = 23.7 × 8.3 μm, n = 50). The basal cell was hyaline, conical to obconical, and bore a tubular appendage. The three median cells were olive-brown, with the central cell darker and adjacent cells slightly lighter. The apical cell was hyaline and conical, bearing 2-4 filamentous apical appendages. The morphological characteristics were similar to those of Neopestalotiopsis species (Razaghi et al. 2024). Two representative isolates (SICAUCC 25-0158 and SICAUCC 25-0159) were selected for DNA extraction, and the ITS (ITS1/ITS4) (White et al. 1990), tef1-α (EF1-728F/1567R) (Carbone et al. 1999), and tub2 (T1/Bt-2b) (O’Donnell et al. 1997) regions were amplified and sequenced. All sequences were deposited in GenBank (ITS: PX206798-PX206799; tub2: PX216750-PX216751; tef1-α: PX216752-PX216753). BLASTn analysis showed that the sequences had 98.7%-100% similarity to species of N. dolichoconidiophora P. Razaghi, F. Liu & L. Cai (CGMCC 3.23490, epitype): ITS: 485/485 bp (100%), 487/487 bp (100%); tef1-α: 835/846 bp (98.7%), 845/856 bp (98.7%); tub2: 732/733 bp (99.9%), 732/733bp (99.9%) (Razaghi et al. 2024). Phylogenetic analysis based on a combined dataset of ITS, tef1-α, and tub2 sequences showed that the two isolates clustered within the clade of the N. dolichoconidiophora complex. Integrating morphological with molecular evidence, the isolates were identified as N. dolichoconidiophora. To confirm pathogenicity, three healthy two-year-old seedlings were inoculated with 500 μl of a spore suspension (1 × 10⁵ conidia/ml) on five leaves each. Three control seedlings were inoculated with sterile distilled water. All treated leaves were bagged and maintained in a greenhouse at 25°C and 70% relative humidity. The test was repeated three times. After ten days, symptoms similar to those observed in the field developed on the inoculated leaves, while no symptoms were observed on the control plants. Neopestalotiopsis dolichoconidiophora was reisolated from symptomatic leaves (100% frequency) and identified based on morphological and molecular characters, fulfilling Koch’s postulates. Neopestalotiopsis dolichoconidiophora was first reported on needle leaves of Cycas revoluta in Jiangxi Province, China (Razaghi et al. 2024). This is the first report of this fungus causing leaf blight on L. formosana. In follow-up studies, it is necessary to further clarify the disease’s occurrence patterns and impacts, and to investigate prevention and control strategies.

Abstract The recovery of graphite has been investigated mainly for black mass from spent Li-ion batteries. However, less research has been performed on the graphite recovery from spent Zn/C and alkaline batteries. Graphite is a critical raw material and it is necessary to search for new secondary sources to recover it. The main advance of this research is to study the application of froth flotation for the recovery of graphite from black mass of spent Zn/C and alkaline batteries. The effect of two thermal pre-treatment processes (roasting at 340ºC and pyrolysis at 600ºC) plus an attrition stage previous froth flotation have been analyzed. Experimental results showed that pyrolysis treatment of black mass from Zn/C and alkaline batteries allows greater selectivity of graphite versus Mn/Zn minerals. This may be due to a modification of the particle size do related to the removal of the finest ones, as well as a modification of the surface chemistry of the graphite and/or manganese oxides. In addition, the thermal treatment also modifies the mineralogical composition of the Mn oxides. Graphical abstract

The growing demand for lithium-ion batteries (LIBs) requires efficient and sustainable recycling solutions. This study investigates bioleaching as an alternative to conventional hydrometallurgical methods, focusing on (i) organic acid-mediated leaching with Gluconobacter oxydans and (ii) sulfuric acid bioleaching with Acidithiobacillus thiooxidans. Experiments were conducted at 26 °C with leaching durations of one to three weeks, depending on the microbial system, at pH 1.35 for sulfuric acid treatments, and with liquid-to-solid ratios equivalent to 100 mL g−1 (A. thiooxidans) or 100 mL g−1 in culture medium (G. oxydans). Results show that indirect bioleaching with G. oxydans achieved high recovery rates for cobalt (96%), manganese (100%), nickel (65%), and lithium (68%), while the direct approach was less effective due to microbial inhibition by black mass components. Similarly, biologically produced sulfuric acid exhibited moderate leaching efficiencies, but chemically synthesized sulfuric acid outperformed it, particularly for nickel (93%) and lithium (76%) after one week of leaching. These findings suggest that bioleaching is a promising, eco-friendly alternative for LIB recycling but requires further process optimization to improve metal recovery and industrial scalability. Future research should explore hybrid approaches combining bioleaching with conventional leaching techniques.

The cathode active materials of lithium-ion batteries (LIBs) contain critical metals including Ni, Co, Mn, and Li. Since these metals are only produced in a few countries, it is necessary to recover them from spent lithium-ion batteries. The concentrated electrode materials of lithium-ion batteries are referred to as black mass (B/M), which contains a large amount of carbon used as the anode material, along with metal oxides used in the cathode. In this study, the effect of roasting temperature in an Ar+CO gas atmosphere on the reduction behavior of NCM (LiNixCoyMn1-x-yO2)-based black mass powder and the recovery of Li was investigated. In the thermogravimetric analysis, the CO2 concentration increased sharply from about 430 ℃ to a maximum value and then decreased, during which a weight gain due to the formation of Li2CO3 was also observed. Above approximately 700 ℃, the concentration of CO increased due to the reaction of CO2 with the C in the B/M due to the Boudouard reaction. In the isothermal roasting in an Ar+CO 50 vol.% atmosphere, the weight of the sample decreased significantly above 696 ℃, and the final weight loss amount also increased with increasing temperature. Most of the significant weight loss is thought to be due to the Boudouard reaction. Li2CO3 was generated regardless of temperature. Above 696 ℃, most of the Ni and Co oxides were reduced to metals, and above 900 ℃, some of the MnO was also reduced and is thought to have been dissolved in the Ni-Co alloy. At temperatures above 696 ℃, where the NiO was fully reduced, the recoveries rate of lithium was approximately 90 % with no significant difference.

A nanoconfined thermoresponsive membrane composed of Ti3C2Tx MXene and hydroxypropyl cellulose (HPC) was developed for selective Li+ extraction. By integrating the electrothermal conductivity of MXenes and hydration-responsive gating of HPC, the membrane forms heterochannels with tunable spacing that regulate ion transport through nanoconfinement-enhanced mechanisms based on interaction energy and hydration radius. While density functional theory calculations predicted stronger sorption for Mg2+, experimental data revealed a clear preference for Li+ uptake from both simulated brine and battery black mass. This selectivity is attributed to favorable interactions of Li+ within the nanoconfined composite channels, where the subnanometer interlayer spacings promote partial dehydration and size-sieving effects. Li+ retention is governed not only by thermodynamic affinity but also by kinetic acceleration in nanoconfined pathways and hydration-based steric control. The membrane exhibits a reversible thermal response and maintains stable performance under Joule heating. It achieves >90% extraction efficiency from simulated Atacama brine and up to 98% Li+ recovery from black mass supplied by VGM Sustainability Solutions (SG3R, Pte. Ltd.).

A techno-economic evaluation of the hydrometallurgical recycling of mixed CAM black mass from spent LIB cells.