Recycling Of Spent Lithium-ion Batteries Research Articles

H2O-balance-regulated cation−anion competitive coordination for selective elements extraction from spent lithium-ion batteries

Key resources necessary for lithium-ion batteries (LIBs) will deplete rapidly if recycling is not considered given the significant demand for LIBs. However, the current recovery method from spent LIBs is hindered by low efficiency, high energy consumption, and severe environmental issues, which curtail the sustainability of recycling industry. Here, we propose a new strategy for selective elements extraction from LiCoO2 based on H2O-balance-regulated cation-anion competitive coordination. The lithium can be preferentially precipitated in deep eutectic solvents (DES) with an appropriate amount of H2O. Such a preferential lithium behaviors contributes to the subsequent precise separation of transition metal elements by further adjusting the water content, thus enabling the recovery of all element and direct regeneration of DES for further spent LIB recycling. The developed DES-based technology can achieve the ultrahigh leaching efficiency of 99.99% for Li and Co with an acceptable recovery efficiency of Li and Co (≥ 91.23%) and a desirable purity of recycled Li2C2O4 and CoC2O4∙2H2O (≥ 98.43%). These Li and Co performances are still maintained at this level even after three-time regeneration of DES. This methodology can also be extended to other recycling chemistries of spent LIBs and lay the theoretical foundation for the recovery of valuable metals from spent battery materials using DESs with a simple process, low energy consumption, and waste-free recycling.

Electrodialysis of Lithium Sulfate Solutions from Hydrometallurgical Recycling of Spent Lithium-Ion Batteries

Recycling lithium-ion battery materials is a crucial step to achieving a circular economy. A hydrometallurgical recycling process of spent lithium-ion battery materials involves leaching by acids and precipitation by bases. A large amount of Li2SO4 leachate solution is generated at the end of the recycling process. Such Li2SO4 solution can be separated by electrodialysis (ED) to form H2SO4 and LiOH solutions, which are reused for leaching and precipitation, respectively, making the recycling a closed-loop process. In this study, an ‘electrodialysis stack constructed with bipolar membranes’ (EDBM) is built with repetitive unit cells consisting of a bipolar membrane, anion exchange membrane (AEM), and cation exchange membrane (CEM), see Fig. 1(a). The effective area for each membrane is 121.8 cm2 (70mm×174mm). The gap between these membranes is 0.8mm, with a mesh inserted to allow flow mixing. All experiments were operated at constant current mode. The feed, acid, and base solutions were recirculated through their tanks at initial concentrations of 1.1, 0.1, and 0.1 mol/L. The ion concentrations of the solutions were measured with Inductively coupled plasma mass spectrometry periodically. The weight and the pH value of the solution tanks were also recorded.The trend of concentration variations of the present stack with up to 6 cell pairs is found to be consistent with that observed with a three-compartment configuration in our previous study [1]. The concentration of H2SO4 increases with time linearly, whereas that of LiOH levels off due to a significant electro-osmosis that drags water through the CEM into the concentrate channel. The present setup differs from the three-compartment design in the bipolar membrane, which splits water to produce H+ and OH- at the internal interface, eliminating the formation of bubbly flows in the unit cell. It is found that the voltage loss across the bipolar membrane ca. 1V accounts for a major part of the unit cell of about 1.27V.The effects of current density, number of cell pairs, and flow rates on the overall stack performance are investigated. Increasing the stack current density accelerates the separation process at the cost of higher voltage losses. It is found that increasing the number of cell pairs can improve the overall production efficiency and reduce energy consumption per cell pair. For instance, at 800 A/m2, the specific energy consumption for LiOH production is reduced to 3.40 kWh/kg with five cell pairs versus 5.83 kWh/kg with two cell pairs. It is also found that increasing the solution flow rate can result into the increase of LiOH solution concentration, ion recovery rate, and current efficiency (Fig. 1b), although the impact of flow rate is low.A small EDBM stack is constructed and tested for Li2SO4 separation in the present study. This work demonstrates that EDBM can be a simple and energy-saving alternative to the current chemical precipitation method to produce LiOH from Li2SO4. The present study provides new insights into optimal operation and design for Li2SO4 EDBM. The findings are helpful in determining how the stack can be scaled up for practical application. Furthermore, a 2D multiphysics model is currently under development to elucidate the coupled transport processes within the unit cell. The model will be validated with experimental data of the present setup. Figure 1

Comparative Study of Hydrogen and Carbothermal Reduction for Recycling of Spent Lithium-Ion Batteries

Comparative Study of Hydrogen and Carbothermal Reduction for Recycling of Spent Lithium-Ion Batteries

Separation of cobalt/lithium in spent NCM-based lithium ion battery leaching solution via reactive extraction-reextraction with microdispersed (G1/L1+G2)/L2 emulsion

Separation of Co and Li in hydrometallurgy for the recovery of valuable metals from waste NCM-based lithium ion battery leaching solution is realized by extraction, with P507/TBP/sulfonated kerosene as extractant. Process intensification is realized via emulsion structure design and novel equipment development, aiming in overcoming operation limitations in traditional equipment caused by increased viscosity and phase ratio. Effects of emulsion structure and operating conditions on extraction are investigated. A multiphase emulsion, (G1/L1+G2)/L2, is designed and prepared by a micro-dispersion module. Efficient extraction is realized with (G1/O+G2)/W emulsion, with which Murphree efficiency of Co2+ reaches 99.1 % within a contacting volume of 7.35 mL, when reverse extraction is realized applying (G1/W+G2)/O emulsion. With (G1/L1+G2)/L2 emulsions, a single-stage extraction and reverse extraction process is realized in 9.11 s, with which Co2+/Li + solution with initial Co2+ concentration of 27.60 mol.% is separated into raffinate of 0.12 mol.% and strip liquor of 81.08 mol.%. The intensification fundamentals are studied, by calculating mass transfer coefficients in formation and flowing stages of varied heterogeneous systems and establishing mathematical models. This study presents simple and effective methods for intensifying extraction and reverse extraction processes with viscous extractants in spent lithium ion battery recycling.

Stacking Fault Formation in LiNi0.6Co0.2Mn0.2O2 during Cycling: Fundamental Insights into the Direct Recycling of Spent Lithium-Ion Batteries.

As the global marketplace for lithium-ion batteries (LIBs) proliferates, technologies for efficient and environmentally friendly recycling, i.e., direct recycling, of spent LIBs are urgently required. In this contribution, we elucidated the mechanisms underlying the degradation that occurs during the cycling of a Li/LiNi0.6Co0.2Mn0.2O2 (NCM622) cell. The results provided fundamental insights into the optimum procedures for direct recycling using a recently developed, state-of-the-art positive electrode material. Capacity fade in NCM622 was induced by cycling at high voltages above 4.6 V vs Li+/Li, during which the rhombohedral symmetry approached cubic symmetry. The selective line broadening and peak shifts that appeared in the X-ray diffraction patterns after cycling indicated the formation of stacking faults along the ch-axis. In addition, high-resolution transmission electron microscopy clarified that rock-salt domains were located on the NCM622 surface before and after cycling. These structural analyses confirmed that the NCM622 particles degrade not at their surfaces but rather in the bulk, contradicting previous reports where degradation during cycling is mainly caused by rock-salt domains on the surface. Material regeneration processes involving the restoration of the original stacking sequence are essential for effective direct recycling.

An Emerging and Consummate Photocatalysis-Assisted Strategy for Efficient Recycling of Spent Lithium-Ion Batteries

An Emerging and Consummate Photocatalysis-Assisted Strategy for Efficient Recycling of Spent Lithium-Ion Batteries

Enabling Future Closed-Loop Recycling of Spent Lithium-Ion Batteries: Direct Cathode Regeneration.

The rapid proliferation of electric vehicles equipped with lithium-ion batteries (LIBs) presents serious waste management challenges and environmental hazards for recyclers after scrap. Closed-loop recycling contributes to the sustainable development of batteries and plays an important role in mitigating raw material shortages and supply chain risks. Herein, current direct cathode regeneration methods for industrialized recycling are outlined and evaluated. Different regeneration methods for spent cathode materials are summarized, which provide a new perspective for realizing closed-loop recycling of LIBs. A reference recycling route for retrofitting existing cathode production lines is proposed and minimizes the costs. In addition to promoting the industrialization of direct cathode recycling, the environmental, economic, and political benefits of battery recycling are also highlighted.

The Recycling of Spent Lithium-Ion Batteries: Crucial Flotation for the Separation of Cathode and Anode Materials.

The recycling of spent lithium-ion batteries (LIBs) has attracted great attention, mainly because of its significant impact on resource recycling and environmental protection. Currently, the processes involved in recovering valuable metals from spent LIBs have shown remarkable progress, but little attention has been paid to the effective separation of spent cathode and anode materials. Significantly, it not only can reduce the difficulty in the subsequent processing of spent cathode materials, but also contribute to the recovery of graphite. Considering the difference in their chemical properties on the surface, flotation is an effective method to separate materials, owing to its low-cost and eco-friendly characteristics. In this paper, the chemical principles of flotation separation for spent cathodes and materials from spent LIBs is summarized first. Then, the research progress in flotation separation of various spent cathode materials (LiCoO2, LiNixCoyMnzO2, and LiFePO4) and graphite is summarized. Given this, the work is expected to offer the significant reviews and insights about the flotation separation for high-value recycling of spent LIBs.

Ion Exchange for the Purification of Co(II) or Ni(II) from Acidic and Ammonia Solutions in the Recycling of Spent Lithium-Ion Batteries

The recycling of critical metals like cobalt and nickel from spent lithium-ion batteries (LIBs) is of immense importance in sustainable manufacturing. This work aims to purify Co(II) and Ni(II) present in acidic and ammonia solutions using ion exchange. AG-1-X8 resin modified with thiocyanate anions (R4N+SCN− resin) was used to separate a small amount of Co(II) from HCl and H2SO4 solutions containing Ni(II) and Si(IV) at pH 3, and the effect of factors such as pulp density, shaking time, and Ni(II) concentration on the adsorption of Co(II) was investigated. The difference in the adsorption behaviour of metal ions onto the R4N+SCN− resin from HCl and H2SO4 solutions was insignificant. Increasing the Ni(II) concentration in the feed negatively affected the loading efficiency of Co(II). The complete elution of the metals from the loaded resin was attained with a 5% NH3 solution. Purolite C100 resin was selected for the purification of Co(II) from a 10% (v/v) NH3 solution containing a small amount of Ni(II), and the best conditions for the complete adsorption of both Co(II) and Ni(II) were determined. Selective elution of Ni(II) over Co(II) from the loaded resin was achieved by dilute H2SO4 solution. The purity of Co(II) in the solution after elution with 2.0 mol/L H2SO4 from the Ni(II) free resin was higher than 99.99%. Ion exchange was effective for purifying a weak acidic or ammonia solution in which there is a significant difference in the Co(II) and Ni(II) concentrations.

A Future Perspective on Waste Management of Lithium-Ion Batteries for Electric Vehicles in Lao PDR: Current Status and Challenges

Lithium-ion batteries (LIBs) have become a hot topic worldwide because they are not only the best alternative for energy storage systems but also have the potential for developing electric vehicles (EVs) that support greenhouse gas (GHG) emissions reduction and pollution prevention in the transport sector. However, the recent increase in EVs has brought about a rise in demand for LIBs, resulting in a substantial number of used LIBs. The end-of-life (EoL) of batteries is related to issues including, for example, direct disposal of toxic pollutants into the air, water, and soil, which threatens organisms in nature and human health. Currently, there is various research on spent LIB recycling and disposal, but there are no international or united standards for LIB waste management. Most countries have used a single or combination methodology of practices; for instance, pyrometallurgy, hydrometallurgy, direct recycling, full or partial combined recycling, and lastly, landfilling for unnecessary waste. However, EoL LIB recycling is not always easy for developing countries due to multiple limitations, which have been problems and challenges from the beginning and may reach into the future. Laos is one such country that might face those challenges and issues in the future due to the increasing trend of EVs. Therefore, this paper intends to provide a future perspective on EoL LIB management from EVs in Laos PDR, and to point out the best approaches for management mechanisms and sustainability without affecting the environment and human health. Significantly, this review compares the current EV LIB management between Laos, neighboring countries, and some developed countries, thereby suggesting appropriate solutions for the future sustainability of spent LIB management in the nation. The Laos government and domestic stakeholders should focus urgently on specific policies and regulations by including the extended producer responsibility (EPR) scheme in enforcement.

Co-products recovery does not necessarily mitigate environmental and economic tradeoffs in lithium-ion battery recycling

Although spent lithium-ion batteries (LIBs) recycling could reduce raw materials production, environmental and economic tradeoffs may not necessarily neutralize impacts associated with additional inputs. Here, we evaluated life cycle environmental and economic tradeoffs of traditional hydrometallurgy for mixed spent LIBs recycling. We revealed impacts of the main and co-products recycling, and their contribution to the impacts from the overall recycling process. Cobalt was the main product due to the highest market value, Li2CO3, nickel, Na2SO4, and graphite were co-products which require additional recycling procedures to obtain. Results suggest co-products recycling doubled the net greenhouse gas emission, and the economic gain decreased by $26 compared to the main product recycling (per kg Co recycled). Conversely, human health impacts were mitigated by co-products recycling due to avoiding virgin co-products production. Our work highlighted that optimizing co-products recycling is vital to minimizing environmental impacts and enhancing the economic feasibility of spent LIB recycling.

Process design and economic analysis of hydrogen roasting integrated with CCU for a carbon-free spent LIB recycling process

In the lithium-ion battery (LIB) recycling process, the roasting step decomposes the complex cathode material into metal oxides before leaching and precipitation. Hydrogen gas is a potential candidate among various roasting agents because of its rapid roasting time and zero CO2 emission. However, additional flue gas emission is unavoidable on the industrial scale to meet the roasting temperature and further crystallization of the produced LiOH slurry. This study proposed and simulated a carbon-free LIB recycling method via an integrating system of hydrogen roasting and CO2 capture and utilization (CCU) composed of the following processes: hydrogen roasting of cathode material; two-way Li extraction; acid leaching; and selective extraction of remaining metal oxide. In the two-way Li extraction, the LiOH slurry was split and converted into LiOH·H2O(s) and Li2CO3(s) via crystallization and the CCU process, respectively. In the CCU process, the slurry was utilized as a wet CO2 absorbent in the flue gas emitted from the roasting and crystallization process. According to sensitivity analysis, 98.10 % Li recovery with zero CO2 emission was accomplished in a split fraction of 0.26. Furthermore, over 99 % recovery of remaining metal resulted from early Li rejection in the metal oxide mixture. Economic analysis was conducted with a 10,000 ton/year recycling capacity, and the net present value of the proposed system is 2.74E + 09 $, 3.08 % higher than the conventional hydrometallurgy system. The proposed system offers higher Li recovery and feasible economic profit with zero CO2 emission and less chemical waste disposal than the conventional system.

Structural Restoration of Degraded LiFePO 4 Cathode with Enhanced Kinetics Using Residual Lithium in Spent Graphite Anodes

Structural Restoration of Degraded LiFePO ₄ Cathode with Enhanced Kinetics Using Residual Lithium in Spent Graphite Anodes

Critical Evaluation of the Potential of Organic Acids for the Environmentally Friendly Recycling of Spent Lithium-Ion Batteries

The need to recover valuable metals from spent lithium-ion batteries (LIBs) is undisputed. However, the environment and the climate are also affected by emissions from the recycling processes. Therefore, the call for environmentally friendly recycling methods is currently louder than ever. In the field of hydrometallurgical recovery of metals from spent LIBs, inorganic acids have so far proved to be an effective, but environmentally problematic, leaching agent, since the pollution of wastewater by high salt loads and the emission of toxic gases cannot be avoided. This has recently led to a trend towards the application of organic acids, as these have significantly more environmentally friendly properties. In order to continue this approach, and to improve it even further from an environmental point of view, this work focuses on the utilization of low leaching temperatures in combination with organic acids for the recovery of valuable metals from spent lithium-ion batteries. This can drastically reduce the required energy demand. Furthermore, attention is paid to higher (50–100 g·L−1) solid-liquid ratios, which are indispensable, especially with regard to the economic establishment of the tested process. The experimental verification of the feasibility using citric, oxalic, and formic acid showed the possibility of an efficient recovery of cobalt, nickel, and lithium. In particular, citric acid in combination with hydrogen peroxide as a reducing agent appears to be a suitable and environmentally friendly alternative to classical inorganic acids, even at low process temperatures, for the hydrometallurgical recycling of lithium-ion batteries.

Nucleation–Oxidation Coupled Technology for High-Nickel Ternary Cathode Recycling of Spent Lithium-Ion Batteries

Nucleation–Oxidation Coupled Technology for High-Nickel Ternary Cathode Recycling of Spent Lithium-Ion Batteries

Novel Phosphate-Chemistry-Based Process Towards Closed-Loop Recycling of Spent Lithium-Ion Batteries

Novel Phosphate-Chemistry-Based Process Towards Closed-Loop Recycling of Spent Lithium-Ion Batteries

A New Route for the Recycling of Spent Lithium-Ion Batteries Towards Advanced Energy Storage, Conversion and Harvesting Systems

A New Route for the Recycling of Spent Lithium-Ion Batteries Towards Advanced Energy Storage, Conversion and Harvesting Systems

Unveiling the recycling characteristics and trends of spent lithium-ion battery: a scientometric study.

The recycling of spent lithium-ion batteries (LIBs) is both essential to sustainable resource utilization and environmental conservation. While spent batteries possess a resource value, they pose an environmental hazard at the same time. Since the start of development to recycle spent LIBs in 1990s, important contributions have been made and a number of achievements have been accomplished by scholars globally. Therefore, it is valuable to summarize the developments on spent LIB recycling and to analyze the characteristics and trends comprehensively. A review of the progress in this field will provide guidance for future development. In this study, recycling characteristics and developing trends including the research foundation, milestone, research hotspot, key technologies, and emerging trends were identified based on visual scientometric analysis followed by a discussion on future research directions in this area. For the analysis, 1041 publications in English were collected, summarized, and categorized. The distribution of scientific publications on spent LIB recycling from 1995 to 2020 displayed an increasing trend in numbers. China made the biggest contribution with 528 publications and basically cooperated with all other countries. The research fields with the highest contributions were "engineering", "chemistry", and "environmental science and technology". The keywords recovery, lithium ion battery, and cobalt appeared in high frequency. "Metal value" was identified as the most frequently used keyword which began to burst in 2005 and ended in 2013.

A Molten-Salt Electrolysis Approach for the Recycling of Spent Lithium-Ion Batteries

Recycling spent lithium-ion batteries can close the strategic metal cycle while averting ecological and environmental footprints. High-temperature molten salts could act as both a promising electrolyte and a solvent to recover valuable Li and transition metals assisted by an electrochemical method that use electrons to break down the crystal structure and thereby sperate the Li and transition metal. In this paper, the molten salt paired electrolysis method employs electrons as both reducing and oxidizing agents and the molten salt as the solvent to separate the desired products without producing any hazardous secondary waste. Since the valence of Fe in LiFePO4 is 2+, the valence can be moved at both directions if proper electrolytes are chosen and appropriate potentials are applied. Moreover, molten salt electrolytes have a wide electrochemical potential range (e.g., electrochemical window) and considerable capability for dissolving lithium salt, which can be used as an electrolyzer to entail specific electrochemical reactions and solvent extraction processes. A molten salt electrolyzer with a solid LiFePO4 cathode and three types of anodes. All the three electrolyzers work well to electrochemically split LiFePO4 to Fe, Li+, and PO4 3 −. Besides molten carbonates, other types of molten salts such as halides, hydroxide, sulfates can be used. The anodic products are CO2, O2 and Fe3O4 if graphite, Ni10Cu11Fe alloy and LiFePO4 anodes are employed, respectively. To minimize the energy consumption and CO2 emissions, the paired electrolysis cells with dual LiFePO4 electrodes is preferable. In all types of eletrolyzers, the recovery rates of both Li and Fe are over 95.2%. Beside LiFePO4, the molten-salt electrolysis approach can be used to treat a variety of cathode materials of LIBs.

Design Optimization of Selective Lithium Leaching of Cathodic Active Materials from Spent Lithium-Ion Batteries Based on the Taguchi Method

The use of lithium-ion batteries (LIBs) has increased in recent years. Thus, efficient recycling is important. In this study, the Taguchi method was used to find the optimal selective lithium leaching parameters for spent LIB recycling. Orthogonal array, signal-to-noise ratio, and analysis of variance were employed to investigate the optimization of selective lithium leaching. The experimental parameters were heat treatment and leaching conditions. The lithium leaching ratio was analyzed by inductively coupled plasma (ICP). The reaction temperature was analyzed by thermogravimetry differential scanning calorimetry (TG-DSC) using lithium cobalt oxide (LCO) and carbon powder, and X-ray diffraction (XRD) was performed after heat treatment at different temperatures. From the XRD analysis, a Li2CO3 peak was observed at 700 °C. After heat treatment at 850 °C, a peak of Li2O was confirmed as Li2CO3 decomposed into Li2O and CO2 over 723 °C. The Li2O reacts with Co3O4 at a high temperature to form LCO. The phase of lithium in the LIB changes according to the conditional heat treatment, affecting the lithium leaching rates. As heat treatment conditions, N2 atmosphere combined with 700 °C heat treatment is suitable, and the solid–liquid ratio is important as a leaching factor for selective lithium leaching.