Search Results (302)

A hydrophobic deep eutectic solvent (HDES) composed of Aliquat 336, decanoic acid, and n-hexanol, diluted with kerosene, was investigated for the selective leaching of LiNi_0.33Mn_0.33Co_0.33O₂ (NMC-111) cathode materials. While conventional choline chloride-based DESs co-dissolve Li and transition metals almost completely, the present HDES–acid hybrid system deliberately sacrifices maximum recovery to achieve selectivity. In combination with a low concentration of H₂SO₄, the HDES enabled preferential dissolution of Co and Ni (~84% and ~80% after 6 h at 90 °C, respectively), while Li and Mn largely remained in the solid residue (>93%). Kinetic modeling indicated that the process is controlled by a surface chemical reaction with apparent activation energies of ~~49 kJ mol⁻¹ (for Ni recovery) and ~51 kJ mol⁻¹ (for Co recovery). The leaching residues were enriched in stable Li-Mn-O phases in a way that offers a basis for stepwise recovery. These findings show that hydrophobic eutectic media coupled with mild acid activation provide a sustainable pathway for the selective recycling of LIB cathodes. Full article

In order to form a solid electrolyte interphase (SEI) layer using aqueous processes, a graphite anode called MG-AQP was designed by wrapping and crosslinking graphite particles with aqueous composites (AQCs), which contained zwitterionic polymer, zwitterion molecules, and lithium salts. First, MG-AQP was used to fabricate a full lithium-ion battery (LIB) cell with Li[Ni_0.8Mn_0.1Co_0.1]O₂ (NMC811) as the cathode, denoted as LIB-MG-AQP//NMC811, to demonstrate its performance via a 0.5 C-rate break-in and 1 C-rate cycling. Accordingly, this showed that LIB-MG-AQP exhibits outstanding cyclic stability. To evaluate its electrochemical performance, MG-AQP and lithium metal were used to fabricate a half cell named LIBs-MG-AQP. According to the initial cyclic voltammetry curve, almost no surface reaction for forming an SEI layer exists in LIBs-MG-AQP, illustrating its high initial coulombic efficiency of 92% at a 0.5 C-rate break-in. These outstanding results are due to the fact that the AQC has fewer cracks, thus blocking solvent molecules from passing from the electrolyte into the graphite anode. This study provides new insights to optimize graphite anodes via 0.5 C-rate break-in rather than conventional SEI formation to save time and energy. Full article

The demand for high energy density in mobile devices (including vehicles and small ships) is increasing. Nickel–Manganese–Cobalt (NMC) ternary, as a battery cathode material, is increasingly being applied because of its higher energy density relative to LiFePO₄ or other traditional materials. But NMC also faces challenges, such as a high degeneration rate and heat generation. So these aspects of Ni content must be clarified. In the current study, two Ni-content battery cells were tested, and the results of other composition cathode cells from the literature were compared. And three typical Ni-content batteries were simulated for searching Ni effects on performance, capacity fade and heat generation. Some findings were achieved: (1) from 0.8 Ni content, it can be seen that the specific capacity growth rate (slope) was much greater than before; (2) cathode materials that have an odd number (that does not surpass 0.7) of Ni content showed a linear capacity degradation trend, but others did not; (3) the Li concentration within material particles did not correspond to absolute stress value but stress temporal gradient; and (4) during discharge, lower Ni content made the heat peak occur earlier but lowered the absolute value; the irreversible heat increased with Ni content non-linearly, so that the higher the Ni content went up, the higher the increase rate of the irreversible heat ratio. Thus, the results of this study can guide the design and application of high energy batteries for mobile devices. Full article

All-solid-state lithium batteries (ASSLBs) employing Li-rich layered oxide (LLO) cathodes are regarded as promising next-generation energy storage systems owing to their outstanding energy density and intrinsic safety. Polymer-in-salt solid electrolytes (PISSEs) offer advantages such as high room-temperature ionic conductivity, enhanced Li anode interfacial compatibility, and low processing costs; however, their practical deployment is hindered by poor oxidative stability especially under high-voltage conditions. In this study, we report the rational design of a bilayer electrolyte architecture featuring an in situ solidified LiClO₄-doped succinonitrile (LiClO₄–SN) plastic–crystal interlayer between a Li_1.2Mn_0.6Ni_0.2O₂ (LMNO) cathode and a poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP)-based PISSE. This PISSE/SN–LiClO₄ configuration exhibits a wide electrochemical stability window up to 4.7 V vs. Li⁺/Li and delivers a high ionic conductivity of 5.68 × 10⁻⁴ S cm⁻¹ at 25 °C. The solidified LiClO₄-SN layer serves as an effective physical barrier, shielding the PVDF-HFP matrix from direct interfacial contact with LMNO and thereby suppressing its oxidative decomposition at elevated potentials. As a result, the bilayer polymer-based cells with the LMNO cathode demonstrate an initial discharge capacity of ∼206 mAh g⁻¹ at 0.05 C and exhibit good cycling stability with 85.7% capacity retention after 100 cycles at 0.5 C under a high cut-off voltage of 4.6 V. This work not only provides a promising strategy to enhance the compatibility of PVDF-HFP-based electrolytes with high-voltage cathodes through the facile in situ solidification of plastic interlayers but also promotes the application of LMNO cathode material in high-energy ASSLBs. Full article

In this study, cells with three different cell chemistries Na₃V₂(PO₄)₂F₃ (NVPF), LiNi_0.6Mn_0.2Co_0.2O₂ (NMC) and LiFePO₄ (LFP) are analyzed in exactly the same setup to compare the hazardous vent gases and their thermal behavior during thermal runaway (TR). Additionally, the influence of different triggers on the failure behavior of NVPF cells is elucidated. The innovative perspective is providing a direct comparison of the three cell chemistries, the influence of the trigger method on the vent gas composition and the thermal behavior. Of the three cell chemistries, LFP releases the least amount of vent gas at 0.02 mol/Ah (41% H₂, 27% CO₂, 8% CO), followed by NVPF at 0.05 mol/Ah (42% CO₂, 17% electrolyte solvent, 15% H₂ and 10% CO) and NMC at 0.07 mol/Ah (36% CO, 24% CO₂, 19% H₂). The maximum vent gas temperature increases from NVPF (265 °C) to LFP (446 °C) and NMC (1050 °C). As for the triggers, overcharge has the highest vent gas production of the NVPF cells at 0.07 mol/Ah. The results offer valuable insight into storage system design and expand the assessment of battery cells. Full article

The traditional recycling process of spent lithium-ion battery(LIB) with high Mn content faces the defects of high cost of neutralization and precipitation, poor economics of Mn extraction, and serious Li loss. Therefore, this paper introduces a comprehensive hydrometallurgical method for extracting valuable metals from high-Mn spent LIB. Particularly, directional precipitation of Mn was achieved by utilizing its redox properties, and shot-process extraction and enrichment of Li was realized by using the extractant HBL121. In a sulfuric acid system, control of the oxidant dosage to 0.8% resulted in high leaching efficiencies for Li, Ni, Co, and Mn, with values of 96.58%, 96.13%, 95.22%, and 94.24%, respectively, under optimal conditions which were C(H₂SO₄) of 3.5 mol/L, V(H₂O₂) of 0.8% (v/v), L/S of 10:1, temperature of 60 °C, and time of 60 min. Subsequently, the addition of KMnO₄ dosage (K_p/K_t) in a ratio of 1:1 resulted in the precipitation of 98.47% of Mn as MnO₂, with Ni and Li precipitation efficiencies of 0.2% and 0.1%, respectively. Cascade extraction of Ni and Co was reached by using Cyanex272 extractant from the solution after Mn precipitation. At an organic-to-aqueous phase ratio (O/A) of 1:5, the Co extraction efficiency reached 98.68%, whereas the loss efficiency of Ni was 5.53%, and Li was less than 0.1%. Adjusting the O/A to 1:1 increased the Ni extraction efficiency to 89.99% and Li loss to 8.95%. Finally, the HBL121 extractant was utilized to extract Li from the Li-rich solution, achieving 95.08% extraction efficiency. The Li was stripped with 2 mol/L H₂SO₄ from the load organic phase, realizing a Li concentration of 11.44 g/L. Thus, this process facilitates the comprehensive and efficient recovery of valuable metals such as Li, Ni, Co, and Mn from spent high-Mn LIB. Full article

Lithium-ion batteries (LIBs) have attracted extensive attention as a distinguished electrochemical energy storage system due to their high energy density and long cycle life. However, the initial irreversible lithium loss during the first cycle caused by the formation of the solid electrolyte interphase (SEI) leads to the prominent reduction in the energy density of LIBs. Notably, lithium formate (HCOOLi, LFM) is regarded as a promising cathode prelithiation reagent for effective lithium supplementation due to its high theoretical capacity of 515 mAh·g⁻¹. Nevertheless, the stable Li-O bond of LFM brings out the high reaction barrier accompanied by the high decomposition potential, which impedes its practical applications. To address this issue, a feasible strategy for reducing the reaction barrier has been proposed, in which the decomposition potential of LFM from 4.84 V to 4.23 V resulted from the synergetic effects of improving the electron/ion transport kinetics and catalysis of transition metal oxides. The addition of LFM to full cells consisting of graphite anodes and LiNi_0.834Co_0.11Mn_0.056O₂ cathodes significantly enhanced the electrochemical performance, increasing the reversible discharge capacity from 156 to 169 mAh·g⁻¹ at 0.1 C (2.65–4.25 V). Remarkably, the capacity retention after 100 cycles improved from 72.8% to 94.7%. Our strategy effectively enables LFM to serve as an efficient prelithiation additive for commercial cathode materials. Full article

With the rapid advancement of new energy electric vehicles, high-capacity nickel-rich layered oxides have emerged as predominant cathode materials in lithium-ion battery systems. However, their widespread implementation necessitates rigorous investigation into cycling stability. We synthesized nickel-manganese-aluminum hydroxide precursors as raw materials by co-precipitation method, and synthesized ultrathin Al₂O₃-coated LiNi_0.9Mn_0.05Al_0.05O₂ cathode materials by hydrolysis reaction. The cathode material was uniformly covered by an Al₂O₃ layer with an average thickness of 5–10 nm by high resolution transmission electron microscopy (HRTEM). Electrochemical performance tests showed that the modified cathode material exhibited significantly enhanced reversible capacity, cycling stability, and rate performance, and a more favorable differential capacity curve. In particular, the LNMA-2 samples were able to maintain 90.6% and 88.3% of their initial capacity after 100 cycle tests (with cutoff voltages of 4.3 and 4.5 V, respectively) at 0.5 C charge/discharge rate. These improved electrochemical properties are mainly attributed to the advantages offered by the unique Al₂O₃ coating structure. This study provides significant theoretical value for designing and optimizing the production of high-nickel cobalt-free cathode materials with high cycling performance. Full article

The growing demand for high-energy, safe, and sustainable lithium-ion batteries has increased interest in nickel-rich cathode materials and solid-state electrolytes. This study presents a scalable wet-processing method for fabricating composite cathodes for all-solid-state batteries. The cathodes studied herein are high-nickel LiNi_0.90Mn_0.05Co_0.05O₂, NMC955, the sulfide-based electrolyte Li₆PS₅Cl, and alternative binders—polyvinyl alcohol (PVA) and polyisobutylene (PIB)—dispersed in toluene, a non-polar solvent compatible with the electrolyte. After fabrication, the cathodes were characterized using SEM/EDX, sheet resistance, and Hall effect measurements. Electrochemical tests were additionally performed in all-solid-state battery half-cells comprising the synthesized cathodes, lithium metal anodes, and Li₆PS₅Cl as the separator and electrolyte. The results show that both PIB and PVA formulations yielded conductive cathodes with stable microstructures and uniform particle distribution. Electrochemical characterization exposed that the PVA-based cathode outperformed the PIB-based counterpart, achieving the theoretical capacity of 192 mAh·g⁻¹ even at 1C, whereas the PIB cathode reached a maximum capacity of 145 mAh.g⁻¹ at C/40. Post-mortem analysis confirmed the structural integrity of the cathodes. These findings demonstrate the viability of NMC955 as a high-capacity cathode material compatible with solid-state systems. Full article

As energy storage technology advances rapidly, the power industry demands accurate state estimation of lithium batteries in energy storage power stations. This study aimed to improve such estimations. An improved Transformer structure was employed to estimate the battery’s state of charge (SOC). The Time Delay Second Estimation (TDSE) algorithm optimized the improved Transformer model to overcome traditional models’ limitations in extracting long-term dependency. Innovative particle filter algorithms were proposed to handle the nonlinearity, uncertainty, and dynamic changes in predicting remaining battery life. Results showed that for LiNiMnCoO₂ positive electrode datasets, the model’s max SOC estimation error was 2.68% at 10 °C and 2.15% at 30 °C. For LiFePO₄ positive electrode datasets, the max error was 2.79% at 10 °C (average 1.25%) and 2.35% at 30 °C (average 0.94%). In full lifecycle calculations, the particle filter algorithm predicted battery capacity with 98.34% accuracy and an RMSE of 0.82%. In conclusion, the improved Transformer and TDSE algorithm enable advanced battery state prediction, and the particle filter algorithm effectively predicts remaining battery life, enhancing the adaptability and robustness of lithium battery state analysis and offering technical support for energy storage station management. Full article

The development of high-performance and stable solid-state lithium batteries (SSBs) is critical for advancing next-generation energy storage technologies. This study investigates LATP (Li_1.3Al_0.3Ti_1.7(PO₄)₃) coatings to enhance the electrochemical performance and interface stability of NCMA83 (LiNi_0.83Co_0.06Mn_0.06Al_0.05O₂) cathodes. Compared to conventional combinations with LPSC (Li₆PS₅Cl) solid electrolytes, LATP coatings significantly reduce interfacial reactivity and improve cycling stability. Structural and morphological analyses reveal that LATP coatings maintain the crystallinity of NCMA83 while fine-tuning its lattice stress. Electrochemical testing demonstrates that LATP-modified samples (83L5) achieve superior capacity retention (65 mAh/g after 50 cycles) and reduced impedance (R_ct ~200 Ω), compared to unmodified samples (83L0). These results highlight LATP’s potential as a surface engineering solution to mitigate degradation effects, enhance ionic conductivity, and extend the lifespan of high-capacity SSBs. Full article

Lithium-rich layered oxide (LLO) has received extensive attention from researchers due to its high initial discharge capacity (≥250 mAh g⁻¹). However, defects such as its high initial irreversible capacity, voltage decay, and poor rate performance have severely limited its commercialization. These issues arise because the Li₂MnO₃ component in LLO is activated during the initial cycle, leading to the participation of lattice oxygen anions (O²⁻) in redox reactions. This results in irreversible oxygen loss (O₂) and subsequent structural phase transitions. To address these challenges, this study focuses on Li₁.₂Ni₀.₁₃Co₀.₁₃Mn₀.₅₄O₂ as the host material, utilizing abundant exposed (010) plane secondary particles and employing a vanadium (V) doping strategy to enhance electrochemical performance. The V forms strong V-O bonds with the lattice oxygen, effectively suppressing irreversible oxygen loss and improving structural stability. The results demonstrate that the LLO achieves the best electrochemical performance as the doping amount is 1 mol%, and the capacity retention improves from 74.5% (undoped) to 86% (V-doped) after 140 cycles at 0.5 C. Full article

Silicon oxide–graphite is a promising high-capacity anode material for next-generation lithium-ion batteries (LIBs). However, despite using a small fraction (≤5%) of Si, it suffers from a short cycle life owing to intrinsic swelling and particle pulverization during cycling, making practical application challenging. High-nickel (Ni ≥ 80%) oxide cathodes for high-energy-density LIBs and their operation beyond 4.2 V have been pursued, which requires the anodic stability of the electrolyte. Herein, we report a nonflammable multi-functional fluorinated ester–based liquid electrolyte that stabilizes the interfaces and suppresses the swelling of highly loaded 5 wt% SiO–graphite anode and LiNi_0.88Co_0.08Mn_0.04O₂ cathode simultaneously in a 3.5 mAh cm⁻² full cell, and improves cycle life and battery safety. Surface characterization results reveal that the interfacial stabilization of both the anode and cathode by a robust and uniform solid electrolyte interphase (SEI) layer, enriched with fluorinated ester-derived inorganics, enables 80% capacity retention of the full cell after 250 cycles, even under aggressive conditions of 4.35 V, 1 C and 45 °C. This new electrolyte formulation presents a new opportunity to advance SiO-based high-energy density LIBs for their long operation and safety. Full article

Pyrometallurgical recycling of lithium-ion batteries presents distinct advantages including streamlined processing, simplified pretreatment requirements, and high throughput capacity. However, its industrial implementation faces challenges associated with high energy demands and lithium loss into slag phases. This investigation develops an integrated reduction smelting–chloridizing volatilization process for the comprehensive recovery of strategic metals (Li, Mn, Cu, Co, Ni) from spent ternary lithium-ion batteries; calcium chloride was selected as the chlorinating agent for this purpose. Thermodynamic analysis was performed to understand the phase evolution during reduction smelting and to design an appropriate slag composition. Preliminary experiments compared carbon and aluminum powder as reducing agents to identify optimal operational parameters: a smelting temperature of 1450 °C, 2.5 times theoretical CaCl₂ dosage, and duration of 120 min. The process achieved effective element partitioning with lithium and manganese volatilizing as chloride species, while transition metals (Cu, Ni, Co) were concentrated into an alloy phase. Process validation in an induction furnace with N₂-O₂ top blowing demonstrated enhanced recovery efficiency through optimized oxygen supplementation (four times the theoretical oxygen requirement). The recovery rates of Li, Mn, Cu, Co, and Ni reached 94.1%, 93.5%, 97.6%, 94.4%, and 96.4%, respectively. This synergistic approach establishes an energy-efficient pathway for simultaneous multi-metal recovery, demonstrating industrial viability for large-scale lithium-ion battery recycling through minimized processing steps and maximized resource utilization. Full article

In the wake of global energy transition and the “dual-carbon” goal, the rapid growth of electric vehicles has posed challenges for large-scale lithium-ion battery decommissioning. Retired batteries exhibit dual attributes of strategic resources (cobalt/lithium concentrations several times higher than natural ores) and environmental risks (heavy metal pollution, electrolyte toxicity). This paper systematically reviews pyrometallurgical and hydrometallurgical recovery technologies, identifying bottlenecks: high energy/lithium loss in pyrometallurgy, and corrosion/cost/solvent regeneration issues in hydrometallurgy. To address these, an integrated recycling process is proposed: low-temperature physical separation (liquid nitrogen embrittlement grinding + froth flotation) for cathode–anode separation, mild roasting to convert lithium into water-soluble compounds for efficient metal oxide separation, stepwise alkaline precipitation for high-purity lithium salts, and co-precipitation synthesis of spherical hydroxide precursors followed by segmented sintering to regenerate LiNi_1/3Co_1/3Mn_1/3O₂ cathodes with morphology/electrochemical performance comparable to virgin materials. This low-temperature, precision-controlled methodology effectively addresses the energy-intensive, pollutive, and inefficient limitations inherent in conventional recycling processes. By offering an engineered solution for sustainable large-scale recycling and high-value regeneration of spent ternary lithium ion batteries (LIBs), this approach proves pivotal in advancing circular economy development within the renewable energy sector. Full article