Effective recovery and recycling of the annually increased lithium iron phosphate battery waste aligns well with the global decarbonization goals, which is of great significance for resource security, environmental protection, and circular economy. At present, much efforts have been devoted for recycling lithium element in spent LiFePO4 cathode materials, while rarely focus on recovering the residual phosphate iron slag. Herein, we propose a novel sodium salt roasting-water leaching procedure to efficiently exploit the phosphorus (P) and iron (Fe) resources, in which the abundant P was extracted selectively and transformed into valuable Na3PO4 & sdot;12H2O. Thermodynamic calculations reveal that the interaction of NaOH and phosphorus iron slag at high temperature endows the transformation of FePO4 to into soluble Na3PO4, and the remaining Fe is collected as Fe3O4. Under the optimal working conditions, the leaching rate of P reached 94.11 %, while less than 1 % for Fe, Al, and Cu. Through subsequent separation and evaporation processes, high purity Na3PO4 & sdot;12H2O and Fe3O4 products can be obtained. This work offers a fresh and sustainable approach for the recovery of P and Fe resources in phosphate iron slag.

Accurate parameter identification for lithium-ion battery equivalent circuit models (ECMs) is critical for battery management systems (BMS) but challenged by initial guess sensitivity and local minima. This study proposes a robust framework integrating logarithmic parameter transformation, the Levenberg-Marquardt (LM) algorithm, and Latin Hypercube Sampling (LHS). The method employs a magnitude-scaled initial guess generation strategy across multiple orders of magnitude through systematic scaling of initial prior estimates, with a four-order-of-magnitude range (0.01x to 100x) implemented as a specific application case. In virtual 2-RC circuit tests, the LM with transformation (LM-Tran) method outperformed three comparative methods - LM without transformation (LM-Normal), Trust-Region-Reflective algorithm without transformation (TRR-Normal), and TRR with transformation (TRR-Tran) - achieving >90% optimal convergence (ExitFlag = 1), R-2 > 0.9995, and a median computation time of 0.086 s/optimization. And for real LFP18650 battery data across 20%-100% SOC, it yielded <10.5 mV voltage residuals (R-2 > 0.996). The parallel-ready framework, compatible with GPU acceleration, enables efficient and physically feasible ECM identification, supporting real-time BMS applications in electric vehicles and energy storage systems.

The large-scale commercial application of sodium-ion batteries (SIBs) urgently requires highly reliable battery management systems (BMS). However, because their fundamental disparities in dynamic kinetics compared to mature lithium-ion batteries (LIBs) remain insufficiently quantified, the direct cross-system migration of existing BMS algorithms is severely hindered. To overcome this challenge, this study proposes a normalized, physics-informed research paradigm for the cross-chemistry benchmarking of battery dynamic kinetics, systematically decoupling and quantifying the intrinsic dynamic kinetic heterogeneity between commercial SIBs and mature LFP and NCM. We extracted second-order equivalent circuit model parameters across an extensive matrix of temperatures (0–50 °C), states of charge (10–100%), and C-rates (0.1–3C), and performed unsupervised machine learning classification combining baseline normalization with principal component analysis (PCA)-based K-Means clustering. Our findings reveal that, in contrast to the highly consistent and symmetric LIBs, SIBs exhibit profound kinetic asymmetry and exceptionally sluggish solid-state diffusion behavior. Particularly under the extreme condition of 0 °C, SIBs experience a severe impedance surge at low C-rates; however, under high-rate excitations (2C–3C), intense localized Joule heating (I2R) triggers a critical non-linear impedance collapse effect. Furthermore, multidimensional clustering analysis mathematically confirms that SIBs occupy a completely non-overlapping and highly fragmented dynamic parameter space relative to LIBs. This study demonstrates that the traditional LIB parameter look-up table paradigm, based on static narrow boundaries, is completely invalid for SIBs. The revealed electro-thermal coupling mechanisms and kinetic clustering boundaries provide a crucial data-driven foundation for developing "cold thermal wake-up" strategies and deploying time-varying adaptive state observers tailored for SIBs.​

As the tritium multiplier in nuclear fusion reactions, the enriched 6Li is indispensable to the development of fusion energy. Among various enrichment strategies, the electrodeposition method has demonstrated superior separation performance. By introducing metallic lithium as the anode material and electrolyte stirring for better mass transport, a separation factor of 1.063 was achieved in a 2-hour separation experiment. Building on this, the separation performance of different organic electrolyte systems was systematically evaluated, yielding a maximum separation factor in a ternary solvent system with the LiFSI lithium salt. Regarding the sustainability of multi-stage separation, the study confirmed that the morphology of lithium metal deposition plays a decisive role in inter-stage mass transfer. By reducing the overpotential, the formation of uniform lithium deposition on the cathode can be controlled, thereby promoting inter-stage mass transfer; in the meantime, the highest second-stage separation factor of 1.210 was achieved at 0.2 V. Finally, based on the above research, a stepwise multi-stage cascading separation model is proposed, which proposes to enhance the overall yield of lithium isotopes by reusing the depleted material from each anode separation stage.

Aqueous Li+/Na+ hybrid-ion batteries (AIBs) have emerged as a promising alternative to address concerns regarding lithium resource scarcity and the safety issues associated with organic electrolytes. However, the development of NaTi2(PO4)3 (NTP) as a high-performance anode material for AIBs is hindered by intrinsic challenges, including material dissolution and the competitive hydrogen evolution reaction (HER) at the electrode-electrolyte interface. Meanwhile, the scalable synthesis of NTPs remains constrained by the complexity of conventional preparation methods. In this work, the N-doped carbon-coated NaTi2(PO4)3 (NTP@NC) as an advanced AIB anode material is synthesized. The carbon coating effectively suppresses HER and material dissolution while maintaining electrolyte pH stability. Remarkably, the NTP@NC demonstrates a high-capacity retention of 66% after 1000 cycles, and the assembled pouch cell retains stable performance over 300 cycles. The large-scale production of the material is successfully achieved with a batch mass of 4 kg. This work establishes a clear correlation among the microstructure, composition, and electrochemical performance, facilitating the practical development of anode materials for high-safety aqueous battery technologies.

This work presents a chloride molten salt etching method for rapid recovery of Ag and Si from EoL c-Si solar cells, utilizing oxidative activation by Cl − to achieve selective component separation within tens of seconds.

With the dramatic accumulation of the end-of-life lithium-ion batteries, their recycling is attracting extensive attention worldwide. To address the problem of low lithium recovery in the current typical hydrometallurgy recovery process, this research uses sodium bisulfate as an auxiliary roasting reagent to extract lithium from spent lithium-ion batteries through sulphation roasting, which can enhance the lithium recovery rate significantly. A systematic study of the sulphation roasting process and the mechanisms was carried out with experiments, thermodynamic calculations, and characterization of the roasted sample phases. The results showed that at a roasting temperature of 600 °C, NaHSO4·H2O/spent LiNixCoyMnzO2 cathode powders (S-NCM) mass ratio of 1.2, and roasting time of 60 min, 95

To achieve large-scale application of solvothermal method and settle structural collapse of polycrystalline ternary NCM cathode materials (LiNi0.8Co0.1Mn0.1O2, NCM811) during long charge and discharge cycling, single-crystalline NCM materials with high cycling stability were prepared by rapid ethanol-water solvothermal method. The morphology and electrochemical properties of NCM materials were characterized by X-ray diffractometry, cross-section scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical measurement. The results show that single-crystalline NCM synthesized with 60 min solvothermal time has the most excellent electrochemical performance. Its reversible capacity reaches 157.28 mA & centerdot;h/g at 1C and retention rate achieves 55.06% after 200 cycles, which is much better than the polycrystalline NCM cathode material. Cross-section scanning electron microscopy results show that the single-crystalline NCM cathode material has no apparent cracks after 200 cycles.

As the tritium breeder in nuclear fusion reactions, the enriched 6Li is indispensable to the development of fusion energy. Compared with other multi-stage separation methods, the electrodeposition method exhibits superior separation performance and significantly reduces the number of stages of multi-stage separation. At the same time, the method uses metal lithium as the initial anode and the cathode product as the next level of raw material. It has faster mass transfer rate and higher current efficiency, and has greater application potential. However, most of the existing studies focus on single-stage separation, and the exploration of multi-stage models is limited. The material transfer process of multi-stage processes is still unknown. In view of these problems, this study systematically studied the effects of various electrolyte systems, mechanical stirring, and deposition time on the separation effect, and carried out multi-stage separation verification and theoretical cascade modeling. The main results are as follows: A separation factor of 1.063 was obtained in a 2-h separation experiment by introducing lithium metal as the anode material and supplemented by electrolyte stirring to improve mass transfer. On this basis, the electrolyte system was optimized, and the highest separation factor of 1.121 was obtained in the ternary solvent system containing LiFSI lithium salt. The study also shows that by reducing the overpotential, the formation of uniform lithium deposition on the cathode can be controlled, thereby promoting inter-stage mass transfer; in the meantime, a two-stage separation factor of up to 1.210 was obtained at a voltage of 0.2 V. Finally, this study proposes a stepwise multi-stage cascade separation model, which improves the overall yield of lithium isotopes by recycling the depleted materials after each stage of anode separation.

Directly applying Lithium-ion Battery (LIB) management logic to Sodium-ion Batteries (SIBs) compromises state estimation accuracy due to inherent electrochemical disparities. To bridge this gap, we systematically characterize and compare the temperature and State-of-Charge (SOC) dependencies of second-order RC model parameters across LFP, NCM, and SIB chemistries. We conducted extensive hybrid pulse power characterization spanning wide operating ranges to quantify parameter sensitivity, thermal entropy, and statistical variability. Our comparative analysis reveals that while SIBs offer superior state observability through quasi-linear Open-Circuit Voltage (OCV) profiles, they exhibit distinct kinetic challenges: specifically, an exacerbated sensitivity of Ohmic resistance to low temperatures and significant heterogeneity in polarization parameters. Addressing these specificities, we propose a "Migration-Oriented Parameter Grouping" framework that categorizes parameters for targeted optimization. Consequently, we advocate for a strategic transition from the conventional "Resistance-Centric" calibration to a "Temperature-Centric," adaptive modeling paradigm. This work provides the theoretical basis and data support essential for developing high-precision BMS for next-generation sodium-based energy storage.

The development of green and efficient lithium isotope separation methods is of strategic importance for sustainable nuclear energy applications. Electrodeposition represents a promising approach, yet the fundamental separation mechanisms and the role of cathode materials require further clarification. This work systematically investigates the mechanism of lithium isotope separation through electrodeposition by integrating computational simulations with experimental validation. The results indicate that the lighter isotope 6Li exhibits weaker solvation interactions and a reduced energy barrier for electron transfer, leading to its preferential deposition. The kinetic isotope effect during the charge transfer step (Li+ + e- -> Li) is identified as the dominant factor in the separation process, contributing significantly more than the limited fractionation induced by diffusion. Two categories of cathode materials-deposition-type (Ni, Cu, stainless steel) and alloy-forming (Zn, Al, Sn)-were evaluated, revealing a strong positive correlation between charge transfer resistance and separation performance, with stainless steel achieving the highest separation factor of 1.048. Furthermore, voltage-dependent studies demonstrate that separation efficiency decreases under high overpotentials due to a transition from charge transfer control to diffusion-limited kinetics. These findings provide fundamental insights into the electrodeposition-based separation mechanism and establish practical guidelines for developing efficient lithium isotope separation systems.

Correction for ‘Microstructural delamination driven recycling of crystalline silicon solar cells via precision molten salt etching’ by Zhengxi Li et al. , Green Chem. , 2026, https://doi.org/10.1039/d6gc02590k.

The existing lithium extraction technologies from salt lakes are confronted with a number of challenges, including limited applicability to brines with elevated Mg/Li ratios and low overall lithium recovery rates. Therefore, it is crucial to develop direct lithium extraction technologies tailored to pristine brines. The core challenge in lithium extraction lies in the effective separation of magnesium and lithium. However, conventional methods struggle to efficiently separate Mg 2+ and Li + in a single‐stage process. Lithium superionic conductors, such as Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 (LATP), are capable of exploiting their internal lithium ion vacancies to enhance the kinetic transport disparity between Mg 2+ and Li + , thus enabling efficient separation. By employing a high‐temperature diffusion technique to introduce Ag + into the interstitial sites of the LATP lattice, the local positive charge density around Ag + is increased. This raises the migration barrier for Mg 2+ within the LATP, significantly improving the Li–Mg separation performance, with a notable long‐term separation coefficient exceeding 25 000. Using 2% Ag‐doped LATP, battery‐grade Li 2 CO 3 with a purity of 99.7% can be produced directly from pristine salt lake brine with a Mg/Li ratio of 500 through a single‐stage separation process.

Achieving efficient carrier separation in transition-metal-oxide semiconductors is crucial for their applications in optoelectronic and catalytic devices. However, the substantial disparity in mobility between holes and electrons heavily limits device performance. Here we develop a general strategy for enhancing hole mobility via reducing their effective mass through metal vacancy (VM) management. The introduction of VM yields remarkable improvements in hole mobility: 430 Efficient charge carrier separation is a substantial roadblock to achieving high performance in photoelectrochemical systems based on transition-metal oxides. Here a metal vacancy strategy is used to enhance hole mobility, resulting in general enhancement of photocurrent density in WO3, TiO2 and Bi2O3 photoanodes.

The effective reuse of iron phosphate residue（IPR） is the key issue in the recycling of spent LiFePO 4 batteries. Therefore, in this study, the reduction leaching of IPR in H 2 SO 4 solution by adding iron powder as reducing agent was investigated and compared with direct leaching. The results show that the leaching rate of IPR reached 97% under the optimum reduction leaching conditions. Kinetic studies show that the activation energy for reduction leaching is 12.71 k J/mol, while that of direct leaching is 21.57 k J/mol. Moreover, the reduction leaching time is reduced by half and the acid consumption is reduced by 30% compared to direct leaching with the same leaching rate. This work provides a scientific guidance to the treatment of iron phosphate residue from the recycling of spent LiFePO 4 batteries.

Composite solid electrolytes (CSEs) based on poly(vinylidene fluoride)-co-hexafluoropropylene (PVDF-HFP) and Li6.4La3Zr1.4Ta0.6O12 (LLZTO) show great potential in building high energy density all-solid-state lithium metal batteries (ASSBs). Nevertheless, the Li2CO3 passivation layer formed on the LLZTO surface not only induces dehydrofluorination of PVDF-HFP but also blocks Li+ transport at the interfaces of PVDF-HFP/LLZTO and CSE/electrodes. Herein, lithium acetate-assisted surficial indiumization with a thickness of 4 nm is carried out to convert the detrimental Li2CO3 into a stable Li+ conductor of LiInO2 (LIO) on LLZTO. With this modification, high air stability of CSEs is achieved which prevents Li2CO3 regeneration and PVDF-HFP dehydrofluorination effectively. Attributed to the unblocked Li+ transport paths at the LLZTO@LIO/PVDF-HFP (LIO-CSE) interface, high ionic conductivity of 3.1 × 10-4 S cm-1 and the Li+ transference number of 0.673 are attained. The Li2CO3-free LLZTO also contributes to constructing robust solid electrolyte interphase with predominantly inorganic components, which successfully decreases the side reactions and ultimately realizes good compatibility at the LLZTO/polymer and electrolyte/electrode interfaces. The assembled Li|LIO-CSE|Li cells exhibit excellent electrochemical stability for 3100 h at 0.5 mA cm-2. The Li/LIO-CSE/LiFePO4 ASSB delivers high-capacity retention of 81.8% after 1000 cycles at 25 °C. This work provides a promising method toward remarkable interfacial compatibility for ASSBs.

With the increasing deployment of photovoltaic modules, recycling of waste photovoltaic has become a topic of great concern. Silver (Ag) represents a significant resource in retired crystalline silicon solar cells (RCSSC). However, conventional methods for the recovery of silver are based on the use of harmful inorganic acids, which give rise to environmental concerns. Furthermore, the use of unsuitable chlorine sources may result in the production of target products with a low level of purity. Herein, we reported a new method featured with ecofriendly mixed organic acid to extract and recycle Ag from retired crystalline silicon wafers. Single-factor experiments and response surface optimization experiments were carried out to find the optimal conditions in the leaching step. A process comprising chlorination precipitation, ammonia dissolution, and liquid phase reduction was constructed for the production of silver powder from the leaching solution. This approach resulted in a high silver leaching yield of 97.38 % and silver purity of 99.85 % before purification with an average particle size of 229.7 nm.

Mn2O3 emerges as a viable anode catalytic layer candidate for nonferrous metal electrodeposition, yet its industrial adoption is hindered by acid-triggered structural collapse and Mn3+ overoxidation. Here, we demonstrate a heterointerfacial engineering strategy that integrates carbon scaffolding with Ce-doped Mn2O3 (C-Ce-Mn2O3), achieving high stability in concentrated sulfuric acid (160 g·L-1) under aggressive polarization. The C-Ce-Mn2O3 anode sustained operation for 104.3 h at a current density of 1 A·cm-2 before reaching the operational failure threshold, whereas pristine Mn2O3 failed within 53.0 h under identical conditions, demonstrating 100.7% longer operational durability, corresponding to the 1095-day theoretical lifetime 2.07-fold over pristine Mn2O3. Density functional theory reveals that the injection of electrons from the Ce 4f orbital into toward Mn(III) optimizes the spin-down electronic state of Mn 3d and serves as an electron-sacrificing buffer zone for Mn(III), avoiding the overoxidation of Mn(III). The test results of Proto-LXRD indicate that carbon fiber can effectively reduce the internal stress of Mn2O3, increase the coating strength, and suppress the cracking and shell formation of the catalytic layer during electrochemical corrosion.

As critical industrial equipment, the operational stability of a centrifugal pump is profoundly affected by hydraulic radial forces acting on the impeller. However, existing research has limitations in systematically characterizing time-varying force patterns, elucidating the correlations between fluid–structure interaction (FSI) and vibration and noise, and developing multi-operating condition analysis methodologies. This study focuses on a horizontal end-suction centrifugal pump, integrating computational fluid dynamics (CFD) simulations to develop a transient radial force dataset covering nine operating conditions ranging from 0.4 Qn to 1.2 Qn. Feature engineering was utilized to extract 23 time-frequency domain features. Through Pearson correlation analysis and agglomerative hierarchical clustering (AHC) algorithms, multi-operating condition classification patterns of hydraulic radial forces were unveiled. Key findings include: (1) the X/Y directional force components exhibit distinct anisotropic correlations with the flow rate; (2) hierarchical clustering based on cosine distance and average linkage divides operating conditions into low, medium, and high flow regimes; (3) feature redundancy elimination requires balancing statistical metrics with physical interpretability. This work proposes an unsupervised learning framework, offering a data-driven approach for the hydraulic optimization of centrifugal pumps and intelligent diagnostics, with engineering significance for improving equipment reliability and operational efficiency.

The functional performance of magnesium hydroxide (Mg(OH)2) is intrinsically governed by its crystallographic morphology. Herein, we demonstrate an electrochemical deposition strategy to synthesize Mg(OH)2 from abandoned MgCl2 resources in salt lakes, achieving simultaneous waste valorization and morphology control. Systematic investigations were conducted on the effects of polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) as surfactants on electrochemical parameters (cell voltage, pH, current efficiency, and energy consumption) and morphological evolution (XRD, SEM, and laser particle size analysis). Results show that the cell voltage and pH increased proportionally with surfactant concentration, with a current efficiency of 93.86% and an optimal energy consumption of 4.15 kW h·t-1 at an optimal PVP concentration of 6 g·L-1. PEG addition exhibited a similar trend in process parameter modulation. Morphological evolution analysis revealed that appropriate PEG dosage promoted the transformation of irregular Mg(OH)2 flakes into near-spherical platelets, accompanied by a measurable increase in particle size. This work establishes structure-property relationships between surfactant molecular design and Mg(OH)2 crystallization, providing theoretical support for the controllable electrochemical preparation of magnesium hydroxide with different morphologies. Furthermore, it opens up a novel and innovative technical pathway to promote the high-value utilization of abandoned magnesium resources in salt lakes.