INCREASING ENVIRONMENTAL PERFORMANCE OF BATTERY TECHNOLOGIES: RECYCLING AS KEY FOR MINIMIZING CRITICAL RAW MATERIAL MINING

7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL INCREASING ENVIRONMENTAL PERFORMANCE OF BATTERY TECHNOLOGIES: RECYCLING AS KEY FOR MINIMIZING CRITICAL RAW MATERIAL MINING Maria Soares1*, , Emanuel J. Lourenço1, Nanna Bjerre-Christensen 2, Thomas Opsomer2, Sara M. Pinto1 1INEGIInstituto de Ciência e Inovação em Engenharia Mecânica e Engenharia Industrial, Porto, Portugal 2Avesta., Ninove, Belgium *Corresponding Author: [email protected]p.pt ABSTRACT The transition to electric mobility is crucial for reducing transportation-related emissions and shifting to renewable energy sources. Lithium-ion batteries dominate energy storage for electric vehicles and stationary applications, but sustainability concerns persist due to the reliance on critical raw materials like lithium, nickel, and cobalt. New gellified battery cells incorporate advanced materials, such as gellified electrodes and high-voltage gel electrolytes, aiming for higher energy densities of 350-400 Wh/kg and cathode potentials up to 4.9 V. However, conventional lithium-ion battery recycling methods—pyrometallurgy, hydrometallurgy, and direct recycling—must be adapted for these cells. In gellified cells, active materials and electrolytes are trapped in a PVDF gel, requiring specialized pretreatment before standard recycling processes can be applied. Effective battery recycling reduces dependence on virgin material extraction, mitigates environmental harm, and supports the European Commission’s goal of recycling 65% of lithium-based batteries by 2025. Studies show that environmental impacts from battery production can be significantly lowered through optimized recycling methods. This research explores an innovative recycling process for 3B battery technology - gellified battery cells, and assesses its environmental impact through Life Cycle Assessment. By comparing this method to virgin material extraction, the study highlights the sustainability benefits of new recycling concepts. Addressing current gaps in gellified cell recycling, this research contributes to advancing battery sustainability and minimizing environmental impact in future energy storage solutions. The proposed recycling process demonstrates high recovery efficiencies, achieving 76.9% for lithium, 76.7% for manganese, and 76.5% for nickel. This advancement significantly mitigates the environmental impacts associated with the extraction of virgin materials and underscores the vital importance of recycling in enhancing battery sustainability. Keywords Critical Raw Materials, Recycling, Life Cycle Assessment, Lithium-ion Batteries, Gellified battery cells 1 INTRODUCTION The transition to electric mobility - e-mobility, is significantly transforming the transportation sector by providing effective means to reduce greenhouse gas emissions and addressing the pressing challenges posed by climate change. As awareness increases regarding the environmental consequences of fossil fuel dependency, electric vehicles have emerged as a vital component of a cleaner and more sustainable future. Governments worldwide are creating policies and providing incentives to accelerate the adoption of electric vehicles. Meanwhile, automakers are making substantial investments in advanced technologies to improve vehicle performance and reduce costs. Nevertheless, the sustainability of electric vehicles is highly linked to the batteries that power them. Current battery technologies depend 7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL heavily on critical raw materials such as lithium, cobalt, nickel, and manganese. This dependence raises concerns regarding resource scarcity and potential environmental degradation. These materials play a key geopolitical role and are vital for EU sovereignty, making their sustainable supply essential, where recycling emerges as a strategic solution to reduce dependency and strengthen resilience. As the demand for electric vehicles continues to rise, it is imperative to develop more sustainable battery solutions that mitigate environmental impacts and ensure long-term viability (David-Mauduit et al., n.d.; Hailemariam & Birkneh, 2024; Lipu et al., 2022). In response to these challenges, the development of gellified batteries offers a promising alternative to traditional lithium-ion batteries. This innovative technology enhances safety by significantly reducing the risks of fire and thermal runaway. Moreover, gellified batteries provide increased durability and an extended lifespan, making them a reliable choice for various applications. Additionally, these batteries demonstrate superior environmental performance through the reduction of toxic solvents and diminished reliance on scarce and critical materials. Their noteworthy energy efficiency and faster charging capabilities further improve electric vehicle performance, positioning gellified batteries as a key innovation in advancing sustainable mobility solutions (Katcharava et al., 2024). Gellified cells are characterized by their unique composition, which includes gellified electrodes, a high-voltage-stable gel electrolyte, and a cathode and anode supported by current collectors. The innovative nature of gellified cells presents unique challenges in obtaining raw materials and developing effective recycling methods. Using gellified electrodes and gel electrolytes alters the material composition, making it more complicated to extract and recover valuable elements such as lithium, nickel, manganese and cobalt. Traditional recycling techniques, primarily designed for liquidelectrolyte batteries, face difficulties in efficiently separating and processing the active materials that are trapped within the gel. This situation highlights an urgent need to establish new recycling processes tailored to these specific materials. Additionally, ensuring a stable supply of specialized materials for gellified components places further demand on the market for critical battery materials. This emphasizes the importance of pursuing innovations in recycling strategies, avoiding the continuous extraction of raw materials (Toro et al., 2023). The aim of this paper is to evaluate an innovative recycling process for 3B battery technology and assess its environmental impact. By comparing this method to traditional practices of virgin material extraction, the study seeks to illustrate the potential of advanced recycling techniques in reducing resource dependency and mitigating environmental impacts. 2 RECYCLING CHALLENGES AND EXISTING METHODS 2.1 Conventional Lithium-Ion Battery Recycling At End-of-Life (EoL) the batteries will first be discharged followed by mechanical pretreatment to get black mass. Full discharge of the battery is needed to avoid potential thermal runaway and the safety concerns following this. The valuable metals and materials can then be accessed from the black mass utilizing pyroor hydrometallurgical processes. The following section will examine and discuss the advantages and disadvantages of each of the mechanical, hydro-, and pyrometallurgical processes. Mechanical pretreatment: The mechanical process essentially consists of shredding or crushing the batteries under inert conditions (i.e., nitrogen or vacuum) (Heimes et al., 2023). The powder obtained can divided into two fractions: coarser (>100 μm), and finer (<100 μm), with the latter being “black mass” (BM). The first can further be divided into aluminum, copper, ferrous and plastics fractions (Sommerville et al., 2020). The black mass contains a mixture of active material from the anode (e.g., graphite) and cathode (e.g., LNMO, NMC) and must undergo post-processing to retrieve the valuable metals. Pyrometallurgical process: The pyrometallurgical approach employs thermal processing to recover valuable metals from the battery waste. The two main options within the pyrometallurgical processing are roasting and smelting. The difference is the temperatures used and the requirement for a pre-heating step (Makuza et al., 2021). 7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL For pyrometallurgical processes, the high-valuable metals will be located in an alloy phase, but Li, electrolyte, and carbon-containing elements will be lost. Besides the material lost, the processes demand significant energy and leaves a substantial environmental footprint (Kallitsis et al., 2022). Hydrometallurgical process: Hydrometallurgy is based on the extraction of valuable metals from liquid phase and can retrieve high purity products due to high selectivity. The process can be divided into three steps: 1) dissolution (leaching), 2) element extraction, and 3) precipitation. Hydrometallurgy is often used downstream pyrometallurgy, but can be applied directly to the BM. The leaching performance strongly depends on the experimental conditions with leaching agent, pH, solid/liquid ratio, time and temperature being the most vital parameters. After leaching the elements can be separated by solvent extraction or ion-exchange, whereafter they will be precipitated out as a salt precursor. Hydrometallurgical processes typically involve the use of strong acids and generate high volumes of waste streams with varying complexity. Furthermore, recrystallization might be required (Tawonezvi et al., 2023). Direct recycling In recent years an alternative to conventional hydrometallurgy has been proposed, namely direct recycling, which shows great promises especially for low-valuable CAMs (e.g. LFP, LNMO). For direct recycling the aim is to heal the active material directly without decomposing the metals to their saltprecursor form. The healing process is often based on compensating the Li deficiency by re-lithiation followed by annealing for recrystallization (Wei et al., 2023). Since direct recycling is non-destructive it is strongly affected by the condition of the input material, mechanical shredding is therefore not a viable option and cells must undergo manual dismantling. Compared to hydroand pyrometallurgy, however, direct recycling shows some advantages in terms of energy consumption and environmental impact (Figure 1) and offer a closed-loop approach by avoiding the resynthesis of the CAM from the metal salts (Fahimi et al., 2022). Figure 1 Comparison of the different recycling approaches (Xu et al., 2021). The three different recycling processes described so far have advantages and disadvantages. Hydroand pyrometallurgy are well-established techniques used for large capacities and can be applied with or without mechanical pre-treatment. However, the recovered material from these processes are precursors which need to be resynthesized to CAM. On the other hand, direct recycling processes have shown the 7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL option of regenerating material properties in a non-destructive manner, ensuring that the material never leaves the battery cycle and can be reused as CAM directly. The major barrier to direct recycling is the lack of scalability. The state-of-the-art recycling facilities in Europe base their recycling schemes on hydroor pyrometallurgy and a combination of these (Forte et al., 2024). 2.2 Limitations of Current Recycling Methods for Gellified Cells The conventional recycling routes described above have been adapted and optimized for classic Lithium-Ion Batteries (LIBs) with a solid cathode and anode sheet separated by a polymer separator wetted by the liquid electrolyte. One of the critical steps in the conventional processes is the recovery or removal of the liquid electrolyte, due to its toxicity and flammability. This is often done by thermal processes. The cells studied in this case are gel-based, with the electrolyte and active materials being trapped herein. The initial step must therefore ensure the recovery of the gel and liberation of the entrapped materials. Since the cell components are gellified, mechanical separation is not feasible, which leaves chemical processing (i.e. solvation). The challenge lies in finding a solvent with high selectivity so only the gel is dissolved. Some of the main limitations for using conventional recycling schemes on the gellified cells are listed in Table 1 . Table 1 Limitation of recycled processes for LIBs. Process Conventional LIBs Limitations for gellified cells Mechanical Liquid electrolyte recovery via evaporation/condensation Physical separation of Shreds Electrolyte trapped in gel structure Chemical separation is required due to the adhesive nature of PVDFbased gel Pyrometallurgical Alloy containing valuable metals Li trapped in slag Burnt PVDF-based gel material Generation of toxic gases (HF, organics) Hydrometallurgical Recovery of valuable metals from alloy or black mass Active materials trapped in gel structure 3 Materials and Methods 3.1 LCA Methodology Life Cycle Assessment (LCA) evaluates the environmental impacts of products or processes throughout their life cycle. It analyses material and energy flows to allow informed sustainability decisions, following ISO14040/14044 standards and consisting of four key stages (ISO Technical Committee, ISO Technical Committee): 1. Goal and Scope Definition: this phase establishes the study’s objectives and boundaries, including the functional unit that measures product performance. 2. Life Cycle Inventory: this stage analyses all inputs (such as raw materials) and outputs (like emissions) to evaluate resource use and environmental impact. 3. Life Cycle Impact Assessment: the assessment evaluates the product’s impacts on various environmental categories, clarifying its overall consequences. 4. Interpretation: in this final step, results are analysed in relation to the study’s goals, allowing for comparisons between products and concluding with recommendations for improved sustainability and process optimization. 3.2 Baseline Assessment 7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL Establishing a baseline reference is essential, as it provides a clear point of comparison that enables the assessment of progress and the measurement of improvements achieved through new developments and innovations in the relevant study. In collaboration with technical partners in from the battery recycling industry, it has been identified that the most appropriate reference conditions for this evaluation would involve extracting and mining virgin materials. This new recycling process highlights that recycling can reduce the demand for extracting and mining raw materials. Therefore, the reference condition will focus on the use of virgin materials obtained from extraction and mining rather than the use of recycled materials. The developed recycling process facilitates the recovery of lithium, manganese, and nickel. Therefore, it is important to evaluate the environmental impacts associated with the extraction and mining of these materials. This analysis has been conducted using SimaPro Multiuser v 9.5.0.0 software in conjunction with the Ecoinvent Database 3.9.1. The functional unit employed for this assessment is 1 kg of extracted material. The analysis focuses exclusively on the material extraction process, thereby excluding all other aspects from the scope of the evaluation. The datasets selected for the production of virgin materials were meticulously chosen to ensure the accuracy and relevance of the data in support of the study, and are as follows: Table 2 Corresponding dataset on Ecoinvent. Material Ecoinvent Dataset 3.9.1 Lithium Lithium carbonate {CN}| lithium carbonate production, from spodumene | Cut-off, U Manganese Manganese concentrate {GLO}| manganese concentrate production | Cutoff, U Nickel Nickel concentrate, 7% Ni {CN}| nickel mine operation and benefication to nickel concentrate, 7% Ni | Cut-off, U The selected datasets encompass the entire range of mining activities, leading to the production of raw materials. These materials will later be processed for use in the production of battery cells. To assess the impact of extracting and producing these materials, the ReCiPe Midpoint (H) 2016 v1.1 method was used, analysing 1 kilogram of each material. The results for lithium carbonate, manganese concentrate, and nickel concentrate are presented below and exhibit more impacts in Global Warming, Terrestrial Ecotoxicity, Human non-carcinogenic toxicity, and Mineral resource scarcity. Therefore, these will be the categories analyzed in detail for the recycling process. Table 3 Results for the most impactful categories -ReCiPe Midpoint (H). Impact Categories Lithium Manganese Nickel Global warming [kg CO2 eq] 10,9281 0,0186 0,9241 Stratospheric ozone depletion [kg CFC11 eq] 0,0000 0,0000 0,0000 Ionizing radiation [kBq Co-60 eq] 0,3363 0,0006 0,0016 Ozone formation, Human health [kg NOx eq] 0,0386 0,0003 0,0039 Fine particulate matter formation [kg PM2.5 eq] 0,0260 0,0001 0,0014 Ozone formation, Terrestrial ecosystems [kg NOx eq] 0,0395 0,0003 0,0040 Terrestrial acidification [kg SO2 eq] 0,0685 0,0002 0,0041 Freshwater eutrophication [kg P eq] 0,0120 0,0000 0,0023 Marine eutrophication [kg N eq] 0,0083 0,0000 0,0000 Terrestrial ecotoxicity [kg 1,4-DCB] 101,1847 0,3416 954,8197 Freshwater ecotoxicity [kg 1,4-DCB] 0,9338 0,0031 1,8616 Marine ecotoxicity [kg 1,4-DCB] 1,2262 0,0040 2,7560 Human carcinogenic toxicity [kg 1,4-DCB] 0,5812 0,0065 0,4975 Human non-carcinogenic toxicity [kg 1,4-DCB] 19,1265 0,0474 20,8873 Land use [m2a crop eq] 0,2611 0,0173 0,0463 Mineral resource scarcity [kg Cu eq] 0,0641 0,0509 0,2340 7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL Fossil resource scarcity [kg oil eq] 2,6670 0,0047 0,2309 Water consumption [m3] 0,0886 0,0003 0,0004 3.3 Proposed Recycling Process for 3B Battery Technology Based on the analysis of conventional recycling techniques, their limitations and benefits, and compatibility with the current design, a general recycling process scheme was developed (Figure 2). Figure 2 Process flow scheme for recycling gellified cells. The process begins with opening the cells and collection of the cell case. During the solvation process, the PVDF gel structure is dissolved, liberating the active materials and electrolyte from the gel matrix. The active materials will be delaminated from the Al and Cu current collectors, which can be collected. After separating the solids from the liquid, the process gives rise to two streams: a liquid solution containing the solvent and PVDF, and the solid containing BM and electrolyte residuals. PVDF is recovered from the solution by evaporation. The BM is dried and washed to recover the electrolyte. Froth flotation is used to separate the Si/C-based anode material from the LMNO cathode material in the BM. Finally, a hydrometallurgical scheme will extract Li, Ni, and Mn from the cathode. 4 RESULTS The recycling process for gellified battery cells has demonstrated high recovery efficiencies for critical raw materials, such as, lithium, manganese, and nickel achieving recovery rates of 76.9%, 76.7%, and 76.5%, respectively. These substantial recovery rates indicate that a significant amount of these valuable materials can be reclaimed, thereby lessening the need for continuous extraction from primary sources.The extraction of 1 kg of lithium, manganese, and nickel generates 10.93 kg, 0.02 kg, and 0.92 kg of CO₂ equivalent emissions, respectively, as seen in Table 4. Recycling can avoid up to 9.12 kg of CO₂ equivalent emissions for every kilogram of recovered material, especially for lithium and nickel, which have higher carbon footprints. Additionally, primary extraction contributes significantly to terrestrial ecotoxicity, with emissions of 101.18 kg 1,4-DCB for lithium, 0.34 kg 1,4-DCB for manganese, and 954.82 kg 1,4-DCB for nickel. Recycling can prevent around 808 kg of 1,4-DCB terrestrial ecotoxicity for each kilogram recycled, largely due to reduced nickel extraction. It can also lower human non-carcinogenic toxicity by about 30.72 kg of 1,4-DCB equivalent. Recycling also lessens mineral resource scarcity. For every 1 kg of lithium, manganese, and nickel extracted, about 0.06 kg Cu eq, 0.05 kg, and 0.23 kg of copper equivalent is depleted, respectively. Recycling can reduce this depletion by approximately 0.27 kg Cu eq for every kilogram recovered, easing the pressure on global supply chains for essential minerals. These values were obtained by multiplying the recycling efficiency by the corresponding environmental impact values, thereby determining the avoided impacts of recycling. These results are presented in Table 5.. 7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL Table 4 Summarized Results for the most impactful categories -ReCiPe Midpoint (H). Impact Categories Lithium Manganese Nickel Global warming (kg CO2 eq.) 10,93 0,02 0,92 Terrestrial ecotoxicity (kg 1,4-DCB) 101,18 0,34 954,82 Human non-carcinogenic toxicity (kg 1,4-DCB) 19,13 0,05 20,89 Mineral resource scarcity (kg Cu eq) 0,06 0,05 0,23 Table 5 Potential avoided impacts through the recycling process. Impact Categories Potential Lithium Avoided Potential Manganese Avoided Potential Nickel Avoided Total Potential Avoided Impacts Global warming (kg CO2 eq.) 8,40 0,02 0,7 9,12 Terrestrial ecotoxicity (kg 1,4-DCB) 77,85 0,26 730,08 808,19 Human non-carcinogenic toxicity (kg 1,4-DCB) 14,71 0,04 15,97 30,72 Mineral resource scarcity (kg Cu eq) 0,05 0,04 0,18 0,27 Although more detailed data is needed to understand the environmental impact of the recycling process itself, these results show that recovering materials can greatly reduce the need for raw material extraction. This leads to lower CO₂ emissions, less environmental pollution, and a more sustainable use of valuable resources. Further improvements in recycling methods could enhance these benefits even more, making recycling a key solution for reducing the environmental impact of battery production. 5 CONCLUSION The growing demand for critical raw materials, including lithium, manganese, and nickel for battery production, emphasizes the necessity for more sustainable resource management strategies. To mitigate the ongoing extraction and mining of these essential materials, it is imperative to innovate and enhance recycling processes, particularly by adapting to the emerging gellified technology. This study has demonstrated that the extraction of these materials contributes significantly to various environmental impacts. Implementing effective recycling methods can divert materials from mining activities, thereby preventing considerable environmental impacts. The developed recycling process shows promising recovery efficiencies of 76.9% for lithium, 76.7% for manganese, and 76.5% for nickel. These efficiencies substantially decrease the environmental impacts typically associated with the extraction of these primary materials. Nonetheless, it is important to acknowledge that additional research is required to assess the environmental impacts associated with the recycling process itself, ensuring that the advantages are fully substantiated. In summary, these findings indicate that recycling is essential for enhancing the environmental performance of battery technologies, reducing dependence on mining operations, and mitigating environmental degradation. 6 ACKNOWLEDGEMENT Funded by the European Union under grant agreement N° 101069910. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Climate, Infrastructure and Environment Executive Agency (CINEA). Neither the European Union nor CINEA can be held responsible for them. 7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL 7 REFERENCES David-Mauduit, P., Gegout, L., Jacoby, E., Oksiutycz-Munyawiri, A., & Romijn, G. (n.d.). The road to sustainable e-mobility batteries. Fahimi, A., Ducoli, S., Federici, S., Ye, G., Mousa, E., Frontera, P., & Bontempi, E. (2022). Evaluation of the sustainability of technologies to recycle spent lithium-ion batteries, based on embodied energy and carbon footprint. Journal of Cleaner Production, 338, 130493. https://doi.org/10.1016/j.jclepro.2022.130493 Forte, F., Moscardini, E., Coletta, J., Toro, L., Yurramendi, L., Hidalgo, J., Ipi�azar, E., Siriwardana, A., Riano, S., Peeters, N., Osen, K., Martinez, A. M., & Gebarowski, W. (2024). First economically and environmentally viable mobile commercial metallurgical plant based on advanced hydrometallurgical and electrochemical technologies able to produce cobalt metal from spent lithium-ion batteries [version 1; peer review: 1 approved, 1 approved with reservations, 1 not approved] . Open Research Europe, 4(32). https://doi.org/10.12688/openreseurope.16753.1 Hailemariam, T., & Birkneh, T. (2024). Advances in Sustainable Battery Technologies: Enhancing Longevity, Recycling, and Alternative Components-- A Review. American Journal of Applied Chemistry, 12(4), 77–88. https://doi.org/10.11648/j.ajac.20241204.11 Heimes, H., Kampker, A., Offermanns, C., Klohs, D., Soldan Cattani, N., Elliger, T., Kwade, A., Ahuis, M., Michaelis, S., & Rottnick, K. (2023). Recycling of Lithium-Ion Batteries (2nd edition, 2023). ISO Technical Committee. (n.d.-a). Environmental management-Life cycle assessment-Principles and framework Management environnemental-Analyse du cycle de vie-Principes et cadre. ISO Technical Committee. (n.d.-b). IS/ISO 14044 (2006): Environmental Management-Life Cycle Assessment-Requirements and Guidelines. Kallitsis, E., Korre, A., & Kelsall, G. (2022). Life cycle assessment of recycling options for automotive Li-ion battery packs. Journal of Cleaner Production, 371, 133636. https://doi.org/10.1016/j.jclepro.2022.133636 Katcharava, Z., Orlamünde, T. E., Tema, L. T., Hong, H., Beiner, M., Iliev, B., Marinow, A., & Binder, W. H. (2024). Designing Conductive Pyrrolidinium-Based Dual Network Gel Electrolytes: Tailoring Performance with Dynamic and Covalent Crosslinking. Advanced Functional Materials. https://doi.org/10.1002/adfm.202403487 Lipu, M. S. H., Mamun, A. Al, Ansari, S., Miah, M. S., Hasan, K., Meraj, S. T., Abdolrasol, M. G. M., Rahman, T., Maruf, M. H., Sarker, M. R., Aljanad, A., & Tan, N. M. L. (2022). Battery Management, Key Technologies, Methods, Issues, and Future Trends of Electric Vehicles: A Pathway toward Achieving Sustainable Development Goals. In Batteries (Vol. 8, Issue 9). MDPI. https://doi.org/10.3390/batteries8090119 Makuza, B., Tian, Q., Guo, X., Chattopadhyay, K., & Yu, D. (2021). Pyrometallurgical options for recycling spent lithium-ion batteries: A comprehensive review. Journal of Power Sources, 491, 229622. https://doi.org/10.1016/j.jpowsour.2021.229622 Sommerville, R., Shaw-Stewart, J., Goodship, V., Rowson, N., & Kendrick, E. (2020). A review of physical processes used in the safe recycling of lithium ion batteries. Sustainable Materials and Technologies, 25, e00197. https://doi.org/10.1016/j.susmat.2020.e00197 Tawonezvi, T., Nomnqa, M., Petrik, L., & Bladergroen, B. J. (2023). Recovery and recycling of valuable metals from spent lithium-ion batteries: A comprehensive review and analysis. In Energies (MDPI) (Vol 16, Issue 3), 1365. https://doi.org/10.3390/en16031365 Toro, L., Moscardini, E., Baldassari, L., Forte, F., Falcone, I., Coletta, J., & Toro, L. (2023). A Systematic Review of Battery Recycling Technologies: Advances, Challenges, and Future Prospects. In Energies (Vol. 16, Issue 18). Multidisciplinary Digital Publishing Institute (MDPI). https://doi.org/10.3390/en16186571 Wei, G., Liu, Y., Jiao, B. L., Chang, N., Wu, M., Liu, G., Lin, X., Weng, X., Chen, J., Zhang, L., Zhu, C., Wang, G., Xu, P., Di, J., & Li, Q. (2023). Direct Recycling of Spent Li-ion Batteries: Challenges and Opportunities towards Practical Applications. IScience, 26, 107676. https://doi.org/10.1016/j.isci.2023.107676 7th INTERNATIONAL CONFERENCE ON WASTES – SOLUTIONS, TREATMENTS AND OPPORTUNITIES, 3-5 SEPTEMBER 2025, FUNCHAL, PORTUGAL Xu, P., Yang, Z., Yu, X., Holoubek, J., Gao, H., Li, M., Cai, G., Bloom, I., Liu, H., Chen, Y., An, K., Pupek, K. Z., Liu, P., & Chen, Z. (2021). Design and Optimization of the Direct Recycling of Spent Li-Ion Battery Cathode Materials. ACS Sustainable Chemistry & Engineering, 9(12), 4543–4553. https://doi.org/10.1021/acssuschemeng.0c09017