High Li Content Research Articles

Lithium pegmatite formation in Kelumute-Jideke pegmatite field, Chinese Altai: Insight from geochronology, petrology and lithium isotope geochemistry

The Kelumute-Jideke pegmatite field is an important lithium (Li)-rich pegmatite mineralization area within the Chinese Altai orogenic belt. There have been four large (Kalu’an No.803, No. 805, No.806, No.807 veins), one medium (Kelumute No.112 vein), nine small deposits (such as Jiamukai, Qunkuer, Azubai) with totally 130,000 tons Li2O found in this area. However, it remains enigmatic whether Li-rich pegmatite formed through fractional crystallization of coeval granite or direct anatexis of metasedimentary rocks. Here we selected pegmatites and their surrounding rocks of metasedimentary rocks and granitic batholith in this pegmatite field to conduct geochronology, whole major and trace element, and Li isotope analyses. The granite intrusions in this field exhibits multiple-stage emplacement ages, including 447.7 ± 4.2 Ma, 405.8 ± 0.0 – 397.4 ± 4.1 Ma, 358.4 ± 3.1–308.4 ± 4.6 Ma, 239.5 ± 1.6 – 213.7 ± 1.5 Ma. The youngest magmatism is coeval with the formation age of rare metal pegmatites. Geochemistry analyses of granites show a peraluminous S-type granite signature with high SiO2 (71.21–75.01 wt%) contents and A/CNK (> 1) ratios. The metasedimentary rocks of Kulumuti Group in this field have experienced weak weathering and exhibit extremely high Li content (maximum of 1193 ppm), which is much higher than that of the Traissic granite (96.1 ppm). The average composition of metasedimentary rocks is used to calculate the partition coefficient of different mineral proportions during the modelled equilibrium melting of the metamorphic phase. This approach determines the mineral proportions and partition coefficients under various conditions. Subsequently, Rayleigh dehydration melting simulations were performed on the Li-rich and Li-poor metasedimentary rocks. The Rayleigh dehydration melting simulations show that melts produced from partial melting of Kulumuti Group display Li content of 80–3435 ppm and δ7Li values of 1.0–8.3 ‰, consistent with natural pegmatites. The low-degree partial melting of claystone-rich metasedimentary rocks (Li-rich) in the Kulumuti Group can produce a preliminary Li-rich melt. However, through Rayleigh fractional crystallization simulation of coeval granite, it is found that the calculated δ7Li value (+6‰) of pegmatites is much higher than that of natural Li-rich pegmatite (average + 3.0 ‰). Therefore, the formation of Li-rich pegmatites in the Kelumute-Jideke pegmatite field is predominantly attributed to the partial melting of Li-rich protoliths with low δ7Li values, rather than high differentiation of Halong granite. The study highlights the importance of anatexis of metasedimentary rocks in formation of Li-rich pegmatite, which is key to mineral exploration for Li pegmatite in Altai orogenic belt.

Kinetics of γ-LiAlO2 Formation out of Li2O-Al2O3 Melt—A Molecular Dynamics-Informed Non-Equilibrium Thermodynamic Study

Slags generated from pyrometallurgical processing of spent Li-ion batteries are reservoirs of Li compounds that, on recycling, can reintegrate Li into the material stream. In this context, γ-LiAlO2 is a promising candidate that potentially increases recycling efficiency due to its high Li content and favorable morphology for separation. However, its solidification kinetics depends on melt compositions and cooling strategies. The Engineered Artificial Minerals approach aims to optimize process conditions that maximize the desired solid phases. To realize this goal, understanding the coupled influence of external cooling kinetics and internal kinetics of solid/liquid interface migration and mass and thermal diffusion on solidification is critical. In this work, the solidification of γ-LiAlO2 from a Li2O-Al2O3 melt is computationally investigated by applying a non-equilibrium thermodynamic model to understand the influence of varying processing conditions on crystallization kinetics. A strategy is illustrated that allows the effective utilization of thermodynamic information obtained by the CALPHAD approach and molecular dynamics-generated diffusion coefficients to simulate kinetic-dependent solidification. Model calculations revealed that melts with compositions close to γ-LiAlO2 remain comparatively unaffected by the external heat extraction strategies due to rapid internal kinetic processes. Kinetic limitations, especially diffusion, become significant for high cooling rates as the melt composition deviates from the stoichiometric compound.

Quantitative pre-lithiation modulation of aluminum foil anode kinetics enables high rate and stable cycling of high-loading all-solid-state batteries

Aluminum (Al) foil holds great promise as a pure alloy anode for all-solid-state batteries (ASSBs) due to its suitable potential, high theoretical capacity, and excellent electronic conductivity. However, it remains challenging to achieve high reversibility and stability of the Al foil anode for ASSBs. Herein, we investigate the morphological and lithium (Li) kinetics evolutions of the Al foil anode paired with sulfide solid-state electrolyte (SSE). We identify that the significant reversible capacity loss stems from diminished Li kinetics at low Li contents (LixAl, 0 < x < 0.5), where the accumulation of pores and pure delithiated Al phase obstructs Li diffusion, increasing interfacial resistance and overpotential. Conversely, the Al foil anode with high Li contents (LixAl, 0.5 < x < 1) demonstrates reversible structures and rapid Li kinetics. Through precise pre-lithiation control, ASSBs with LiNi0.8Co0.1Mn0.1O2 (NCM811) cathodes exhibit outstanding rate capabilities and cycling stability, achieving over 4,000 cycles with 82.1 % capacity retention at 5C and demonstrating long-term cycling over 1,000 cycles with nearly 100 % capacity retention at ultra-high loadings. This work offers a viable strategy for advancing practical-level ASSBs with enhanced performance and longevity, contributing valuable insights to future battery technology.

Effect of lithium concentration on the network connectivity of nuclear waste glasses

Structure of borosilicate glasses with varying Li2O contents were investigated using Magic Angle Spinning (MAS) Nuclear Magnetic Resonance (NMR), employing 6Li, 11B, 23Na, 27Al and 29Si nuclei. 11B MAS NMR revealed that increasing Li2O contents result in formation of [BO4]− sites at the expense of BO3. 11B{6Li} and 27Al{6Li} dipolar heteronuclear multiple quantum correlation (D-HMQC) NMR revealed Li as a charge compensator for anionic tetrahedral sites with increased Li. 11B{6Li} J-coupling mediated HMQC NMR suggested the possible association of Li with non-bridging oxygens on Q2 and Q3 sites, indicating its dual role in the glass network. 29Si and 23Na MAS NMR spectra showed depolymerisation of the silicate network and shortening of Na-O bond lengths with increased Li. NMR results are supported by Raman spectroscopy and thermal analysis that indicate depolymerisation of the silicate network and a reduction in glass transition temperature at higher Li content.

Li enrichment in peridotites and chromitites tracks mantle-crust interaction

The ultramafic massifs of the Serranía de Ronda in southern Spain are the Earth's largest exposures of subcontinental lithospheric mantle (SCLM) peridotites (∼450 km2). These ultramafic massifs experienced asthenosphere melt percolation during their crustal emplacement. Mixing of these mafic melts with anatectic melts and fluids led to the formation of a world's unique Ni-arsenide-rich chromitite ores (hereafter CrNi ores) associated with orthopyroxenite and/or cordieritite (i.e., > 90 % volume of cordierite) hosted within the peridotites. This study uses laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to investigate the Li in rock-forming minerals of peridotite and CrNi ores to evaluate the role of Li as crustal tracer. Clinopyroxene crystallized from asthenospheric melts exhibits high Li contents (up to 8.5 ppm), exceeding the average values of the upper mantle (∼ 0.7 ppm), whereas orthopyroxene, olivine, and Cr-spinel from peridotite are mostly Li-depleted. In contrast, all rock-forming minerals of CrNi ores have abnormally high Li contents, displaying an overall Li enrichment trend toward the external parts of ultramafic massifs, on the way to the crustal rocks. This trend is evident in Cr-spinel from the CrNi ores, which display 6.9–7.9 ppm Li in the deepest portions of the massif (Arroyo de la Cala CrNi ore) up to 1.4–8.5 ppm in the shallowest part (La Gallega CrNi ore), as well as in orthopyroxenes that have 31.3–44.7 ppm Li in Arroyo de la Cala, and 45.1–51.4 ppm Li in La Gallega. Cordierite is present only in the CrNi ores situated in the external part of the ultramafic massifs, exhibiting 113.15–160.82 ppm Li in the Barranco de las Acedías CrNi ore and 36.5–60.5 ppm Li in La Gallega CrNi ore. Similarly to Li, LREE, fluid-mobile elements (K, Rb, Ba), and Sr in orthopyroxenes from the CrNi ores display enrichment from the inner to the outer parts of the ultramafic massif. These geochemical variations suggest that Li enrichment in CrNi ores and host peridotites was a twofold process: (1) asthenospheric melt percolation slightly increased Li abundances in the SCLM peridotites by modal and cryptic metasomatism involving clinopyroxene; (2) additional infiltration of Li-bearing crustally-derived fluids during the intracrustal emplacement of the mantle section boosted the Li contents of minerals in the CrNi ores. Our results highlight that Li may effectively track the interaction of the SCLM with crustal components.

Investigation of in-situ ion release and surface film formation of hcp Mg-Li thin films

In this work, the dissolution process of magnetron sputtered Mg-Li thin films was investigated by in-situ flow cell/ICP-MS measurements and ex-situ ICP-MS measurements after longer immersion and additional XPS measurements. High Li concentrations are released due to a Li rich carbonate layer formed in air. The depletion of Li leads to preferred Mg release before preferred Li release occurs due to the higher activity of Li and incorporation of Mg in corrosion products. This data provides a baseline for developing release profiles for medical application, more generally, it unravels details of the corrosion mechanism of lightweight MgLi alloys.

Lithium isotopic records of anthropogenic activity in the Xiaoqing River basin, eastern China

The environmental impact of the discharge of lithium (Li) by anthropogenic activity has been overlooked. By analyzing Li concentrations and isotope compositions (δ7Li) of water and sediment samples, this study evaluates the influence of anthropogenic Li discharge on the Xiaoqing River and Laizhou Bay, which are heavily polluted areas in China. High Li concentrations of the river water (up to 7.8 μmol/L) should be linked to anthropogenic Li discharge. However, no profound δ7Li anomalies were observed, preventing identification of the exact discharge sources. In the river sediments, Li concentrations (19.0–45.0 μg/g) were weakly correlated with Zn, Cu, and Cr concentrations, whereas δ7Li values ranged from 0.6 ‰ to 13.9 ‰ with high values being accompanied by high contents of total organic carbon and heavy Cr isotope compositions (δ53Cr). All these point to significant influence of anthropogenic activity on the Li budget of river sediments. A simple mass balance calculation indicates that smelters, Li-bearing therapeutic drugs, and secondary Li-ion batteries are the main anthropogenic Li sources. In contrast to river sediments, marine sediments in the Laizhou Bay were broadly homogeneous at both spatial and temporal scales, indicating no significant influence of anthropogenic Li discharge. Overall, our data indicate that Li isotope systematics in river sediments, especially sediments near intense anthropogenic activity, are effective at tracing potential Li pollution and can help obtain accurate results for environmental inspection.

Clean and efficient extraction of lithium from montebrasite ore by aluminum sulfate roasting method: Thermal behavior and process optimization

Amidst the surge of Li demand, technology development for Li extraction from diverse Li resources has gained considerable interest. Montebrasite, a significant lithium ore, is distinguished by its high Li content. Despite its potential, research into its processing technologies are scarce, leading to its limited and slow industrial adoption. On this basis, a novel process combining aluminum sulfate roasting and water leaching was proposed in this study to achieve its clean and efficient utilization. Firstly, thermal behaviors of montebrasite were investigated through various characterizations. It was observed that montebrasite underwent obvious decomposition above 700 °C, and began to melt after 800 °C. The mineral phases transformed into Li3PO4, AlPO4 and Al2O3 after decomposition. Thermodynamic calculation indicated that when Al2(SO4)3 was used as roasting agent, Li+ can be entirely substituted by Al3+ to form soluble Li2SO4, while Al3+ combined with PO43− to form insoluble AlPO4, enabling selective and efficient Li extraction. The experimental results demonstrated a high agreement with thermodynamic analysis. Under the optimal conditions (roasting: 760 ℃, 1.0 h, 29.4 % Al2(SO4)3), 94.1 % Li was extracted selectively, while only 0.04 % Al and 0.3 % P entered into solution. The leach residue, primarily composed of AlPO4, SiO2, mullite and Al2O3, can be recycled for further utilization. This process offers distinct advantages over traditional salt roasting methods, including reduced reagent usage and elimination of solid waste discharge. It presents an efficient, cost-effective and environmentally benign pathway for the utilization of montebrasite.

Direct Lithium Extraction from α-Spodumene through Solid-State Reactions for Sustainable Li2CO3 Production.

With increasing battery demand comes a need for diversified Li sources beyond brines. Among all Li-bearing minerals, spodumene is most often used for its high Li content and natural abundance. However, the traditional approach to process spodumene is costly and energy-intensive, requiring the mineral be transformed from its natural α to β phase at >1000 °C. Acid leaching is then applied, followed by neutralization to precipitate Li2CO3. In this work, we report an alternative method to extract Li directly from α-spodumene, which is performed at lower temperatures and avoids the use of acids. It is shown that Li2CO3 is formed with >90% yield at 750 °C by reacting α-spodumene with Na2CO3 and Al2O3. The addition of Al2O3 is critical to reduce the amount of Li2SiO3 that forms when only Na2CO3 is used, instead providing increased thermodynamic driving force to form NaAlSiO4 and Li2CO3 as the sole products. We find that this reaction is most effective at 4 h, after which volatility limits the yield. Following its extraction, Li2CO3 can be isolated by washing the sample using deionized water. This energy-saving and acid-free route to obtain Li2CO3 directly from spodumene can help meet the growing demand for Li.

Utica/Point Pleasant brine isotopic compositions (δ7Li, δ11B, δ138Ba) elucidate mechanisms of lithium enrichment in the Appalachian Basin

Global Li production will require a ∼500 % increase to meet 2050 projected energy storage demands. One potential source is oil and gas wastewater (i.e., produced water or brine), which naturally has high total dissolved solids (TDS) concentrations, that can also be enriched in Li (>100 mg/L). Understanding the sources and mechanisms responsible for high naturally-occurring Li concentrations can aid in efficient targeting of these brines. The isotopic composition (δ7Li, δ11B, δ138Ba) of produced water and core samples from the Utica Shale and Point Pleasant Formation (UPP) in the Appalachian Basin, USA indicates that depth-dependent thermal maturity and water-rock interaction, including diagenetic clay mineral transformations, likely control Li concentrations. A survey of Li content in produced waters throughout the USA indicates that Appalachian Basin brines from the Marcellus Shale to the UPP have the potential for economic resource recovery.

Li-mineralized pegmatite of anatectic origin: Constraints from Li[sbnd]Hf isotopes and geochemical modeling

Pegmatites are important reservoirs of lithium resources. There is an ongoing debate as to whether Li-mineralized pegmatites were generated from evolved granitic systems via extreme differentiation or by direct melting of metasedimentary rocks. The Chinese Altay is one of the largest pegmatite provinces in the world, and includes many rare-metal pegmatites (e.g., Koktokay, Kelumute, Kaluan and Azubai). However, they display significant differences in formation ages and isotopic compositions compared with the neighbouring or potential parental granites. In this contribution, we present a case study of the Kaluan Li ore deposit in the Chinese Altay, elucidating the origins of pegmatites and related Li mineralization. The Kaluan Li-mineralized pegmatites are characterized by high SiO2, K2O, Na2O, Li, Cs, Ta, and Rb contents; low Fe2O3T, MgO, Ba, and Sr contents; and peraluminous signatures. They have homogeneous HfLi isotopic compositions (εHf (t) = −0.6 to +2.5; δ7Li = +1.6 to +5.8‰) that are within the range of HfLi isotopic compositions of the Kulumuti Group schists (εHf (t) = −2.8 to +7.5; δ7Li = −8.6 to +10.8‰). In addition, the chemical compositions of the melt derived from the partial melting of the Kulumuti Group by phase equilibrium modeling are compatible with our analyses of the Kaluan Li-mineralized pegmatites. These similarities suggest that the Kaluan Li-mineralized pegmatites were derived from the partial melting of the Kulumuti Group schists at depths during the Triassic, in a post-orogenic and extensional setting. The generation of these pegmatites was mostly controlled by biotite dehydration melting at relatively high temperatures, rather than by the low-temperature melting of muscovite. Trace elements modeling results show that approximately 33–36% partial melting of the average Kulumuti Group schist may produce melts with maximum Li concentrations ranging from 664 to 751 ppm. Subsequently, a high degree of fractionation exceeding 85%, was required for the Li concentration of the residual melt to reach concentrations suitable for crystallization into albite-spodumene pegmatites. Based on our research, an anatectic origin model may have general applicability in explaining the genesis and mineralization of rare-metal pegmatites in the Chinese Altay.

Anatomy and genesis of the world’s largest carbonate-hosted Zn-Pb deposit: New insights from ore characteristics, Zn-Pb-C-O isotopes, and trace element constraints of the Huoshaoyun deposit, Karakorum Range, Xinjiang

The Huoshaoyun deposit in the Karakorum area of NW China is the world’s largest zinc-lead carbonate ore deposit. Here we investigate the genesis of the mineralization based on multiproxy investigations. The deposit contains zinc-lead carbonate and sulfide minerals, with smithsonite (Smt), cerussite (Cer), and sulfides accounting for 85%, 10%, and 5% of the total lead and zinc resources, respectively. Three ore-forming stages, involving Smt, Cer, and sulfides ores were summarized. The Smt mineralization is characterized by veined, massive, and stratified Smt forming horizontal sedimentary layered ore and vertical feeder veins similar to the SEDEX-type deposits. The sulfide and Cer veins display typical hydrothermal characteristics and are superimposed on the massive Smt ores. The Smt ores show high Li, Be, Cr, Y, Ba, Nd, Yb, and Zr contents, whereas the Cer veins have extremely high Sr contents (up to 3814–9174 ppm) and low Zr contents (less than 0.01 ppm). Galena and sphalerite show higher Cd concentrations compared to Smt and Cer ores.The Smt ores differ with different spatial locations, with Smt ores formed at the vent have δ66Zn values of +0.15‰ to +0.21‰, the massive Smt formed close to the vent show a value of +0.13‰, and those formed away from the vent show a value of 0.05‰, all values being close to 0. The sulfides have δ66Zn values of −0.09‰ to +0.04‰. The C-O isotopes of Smt ores are similar to both altered and unaltered host limestone, suggesting that the limestone was a potential source for carbon and oxygen. Quartz with veined Smt shows magmatic signatures with δ18OVSMOW of +1.14‰ to +2.23‰, high Pb (115–401 ppm) and Zn concentrations (390–997 ppm), whereas quartz associated with sulfide has meteoric fluid signature with the lowest δ18OVSMOW (−14‰ to −10.7‰), low Pb (11.6–49.0 ppm) and Zn (18.1–72.8 ppm) concentrations. The temperature of equilibration computed based on oxygen isotope fractionation between Smt and coeval quartz indicate a dual source with that of quartz derived from an aqueous fluid, whereas the source for Smt might involve CO2 or HCO3−.We trace multiple metallogenic stages for this deposit including exhalation, hydrothermal deposition, and fault-controlled sulfide vein formation. The largest orebody (III-1) preserves a 16 Mt reserve of Zn and was formed by crust-mantle interaction at ca. 195 Ma in the early development of the Linjitang post-arc rift system. Fluid convection, zinc enrichment driven by granitic magma, volcanic activity, and karst alteration induced by acid rain in a lagoonal environment promoted ore enrichment.

Geochemical characteristics, Li source and genesis mechanism of thermal mineral water in Sichuan Basin, SW China

Thermal mineral water (temperature >25 °C) is a valuable resource, especially when it contains a certain amount of Li. In this study, an attempt was made to elucidate the factors affecting spatial distribution of lithium (Li) resources and interpret the formation mechanisms of thermal mineral waters in the Sichuan Basin. The spatial distribution, reservoir temperatures, and hydrochemical characteristics of thermal mineral waters were systematically analyzed in the Sichuan Basin, preliminarily revealing Li sources through hydrochemical methods. Results are showed as follows: (1) The Li-bearing (Li ≥ 1 mg/L) thermal mineral waters are mainly distributed in the southwestern part of the Sichuan Basin. There are three sites of thermal mineral waters with Li content greater than 25 mg/L with the hydrochemical type of Cl–Na type: Pengji Well (37.7 mg/L), Foguanghu Well (99.5 mg/L) and Zhougongshan New Well (118.0 mg/L). Among them, the Foguanghu Geothermal Well and the Zhougongshan New Well have high Li content and low Mg/Li (10.7 and 2.5), indicating great potential for utilization. (2) The Li-bearing thermal mineral waters are mainly formed in the fissure and pore reservoirs of the Middle–Lower Triassic. They are mainly affected by the dissolution of halite minerals and the deeply buried ancient seawater of the Triassic. The Li-bearing thermal mineral waters possess high contents of total dissolve solids (TDS) (4.3–230.0 g/L), Cl (0.7–142.9 g/L), Na (0.5–76.7 g/L), K (0.1–52.0 g/L), B (4.1–739.6 mg/L), and Li (1.5–118.0 mg/L). Moreover, the temperature of the geothermal reservoir ranges from 40 to 150 °C. The geothermal reservoir temperatures calculated by K–Mg and Mg–Li geothermometers are positively correlated with the Li content. (3) The Li source of the thermal mineral waters of the Sichuan Basin are dominated by multiple factors: first, Li concentration by evaporation, concentration and deep-seated metamorphism of ancient Triassic seawater; second, water–rock interaction between deep thermal mineral waters and mung bean rock or Emeishan basalt; and third, active tectonic activity and deep faulting induced upward flow of Li in deep fluids. This research enhances understanding of the formation of thermal mineral waters in the Sichuan Basin, offering scientific basis for the exploitation of Li resource.

Continental crust recycling in collisional zones: insights from Li isotope compositions of the syn-exhumation and post-collisional mafic magmatic rocks

Syn-exhumation and post-collisional mafic magmatism in continental collision orogenic belts may provide insights into the nature of orogenic lithospheric mantle and recycled continental components in continental subduction zones. Lithium and its isotopes have emerged as potentially valuable tools for shedding light on the origin of these magmas, given the contrast Li contents and isotopic compositions between the subducting continental crust and the mantle. Here, we present high-precision Li isotopes data for representative orthogneiss, continental eclogite, syn-exhumation and post-collisional mafic magmatic rocks from the North Qaidam orogen. The syn-exhumation mafic magmatic rocks have relatively higher Li contents (26.5–50.0 ppm) and lower δ7Li values (−1.01‰–1.48‰) than those of the post-collisional mafic magmatic rocks (Li = 11.1–22.7 ppm, δ7Li = 1.20‰–3.38‰), which are comparable to those of orthogneiss and continental eclogite, respectively. Dehydration and melting modelling results show that these mafic magmatic rocks have similar Li contents and δ7Li values to the continental eclogite- and orthogneiss-derived melts but are different from their derived fluids. Monte Carlo simulation for Li-Nd isotopes suggests the syn-exhumation and post-collisional mafic rocks could be derived from an enriched mantle source that contains ∼3–8% continental crustal components dominated by the orthogneiss and continental eclogite. The calculated results are consistent with the results from the previous study simulated by trace elements. Therefore, our results highlight Li isotopes as a potential tool to trace the nature of the continental crustal components recycling in continental subduction zones.

Redox Mechanisms upon the Lithiation of Wadsley-Roth Phases.

The Wadsley-Roth family of transition metal oxide phases are a promising class of anode materials for Li-ion batteries due to their open crystal structures and their ability to intercalate Li at high rates. Unfortunately, most early transition metal oxides that adopt a Wadsley-Roth crystal structure intercalate Li at voltages that are too high for most battery applications. First-principles electronic structure calculations are performed to elucidate redox mechanisms in Wadsley-Roth phases with the aim of determining how they depend on crystal structure. A comparative study of two very distinct polymorphs of Nb2O5 reveal two redox mechanisms: (i) an atom-centered redox mechanism at early stages of Li intercalation and (ii) a redox mechanism at intermediate to high Li concentrations involving the bonding orbitals of metal-metal dimers formed by edge-sharing Nb cations. Our study motivates several design principles to guide the development of new Wadsley-Roth phases with superior electrochemical properties.

Unveiling the origin of severe hot cracking susceptibility in Al-Li alloys

This work reports a new mechanism for the severe hot cracking susceptibility (HCS) of cast Al-Li alloys. In contrast to the narrow vulnerable solidification temperature range increasing cracking resistance, alloys with high Li content or solute content, which are supposed to show lower HCS, instead exhibit anomalously high HCS. Results reveal that this phenomenon arises from a variety of Li-rich inclusions distributed in the interdendritic paths, including Li2O, LiAlO2, Li2CO3 and LiH. These particles can form spontaneously with O2, CO2 and H2O during solidification, deteriorating the interfacial bonding capacity. Meanwhile, the occupation of refilling channels for residual liquid increases the potential risk of microcrack initiation. These unfavorable factors promote the rapid propagation of cracks from the casting surface inward, which eventually leads to catastrophic fractures.

Microstructure and mechanical properties of Sc/Zr modified 1460 Al–Li alloy fabricated by laser powder bed fusion

The preparation of Al–Li alloy by laser powder bed fusion (LPBF) technology, especially Al–Li alloy with high Li content, is of great significance for lightweight of aerospace equipment. However, the significant susceptibility of Al–Li alloys to hot cracking during the process limits their advancement. This study starts from the two aspects of process control and composition modification, to achieve the production of crack-free and high-quality 1460 Al–Li alloys. Crack-free 1460 specimens can only be prepared at extremely low scanning velocity. The process window is markedly expanded by Sc/Zr modification. The heterogeneous nucleation of Al3(Li,Sc,Zr) results in significant grain refinement and effectively suppresses crack initiation and propagation. The unique bimodal heterogeneous microstructure endows the alloy with notable mechanical properties. After the addition of 0.6Sc-0.3Zr, the ultimate tensile strength (UTS), yield strength (YS), and elongation (δ) of 1460 alloy are increased by 104 %, 158 %, and 43.9 %, respectively. The strength-plasticity synergism is primarily attributed to grain refinement strengthening, precipitation strengthening, and hetero-deformation induced strain hardening resulting from its unique bimodal heterogeneous microstructure. The UTS and YS of 1.2Sc-0.6Zr modified 1460 alloy increased by 156 % and 279 %, respectively. However, this further increase in the Sc/Zr content significantly deteriorates the plasticity of the alloy. This work establishes a foundation for advancing the use of Al–Li alloys in high-performance, lightweight, and complex aerospace structures.

Lithium Toxicity in Lepidium sativum L. Seedlings: Exploring Li Accumulation’s Impact on Germination, Root Growth, and DNA Integrity

The predicted increase in demand for minor metals for modern technologies raises major concerns regarding potential environmental concentration increases. Among the minor metals, lithium (Li) is particularly noteworthy due to growing demand for battery production. Concerns have been raised about the impact on biota of increasing Li concentrations in the environment. To expand the knowledge of the effects of Li on plants, garden cress (Lepidium sativum L.), a model plant for ecotoxicity assay, was tested in a 72 h test in Petri plates. The results showed a stimulation effect of Li at the lowest concentration (Li chloride 10 mg L−1) on seed germination and primary root elongation. Conversely, higher Li concentrations (50 and 150 mg L−1) caused a progressive impairment in both parameters. A genotoxic effect of Li on root cells, evaluated through the alkaline comet assay, was observed at each concentration tested, particularly at 150 mg L−1 Li chloride. Elemental analysis showed that Li accumulated in the seedlings in a dose–concentration relationship, confirming its ability to be readily absorbed and accumulated in plants. Given the likely increase in Li levels in the environment, further research is required to clarify the toxicity mechanisms induced by Li on growth and nucleic acids.

Genesis of Danping bauxite (Northern Guizhou, China) and associated lithium: Evidence from LA-ICP-MS analysis of Al-bearing minerals

Lithium (Li), as an essential element of green new energy technology, is a global strategic resource. Sedimentary Li is primarily associated with bauxite, with a local grade of >1000 ppm, and has a huge utilization prospect. However, fine particles limit the study of the occurrence of Li. The Danping bauxite deposit, located in northern Guizhou, China, which accompanying considerable Li resources. In this study, in situ elemental concentration analyses were conducted by laser ablation-inductively coupled plasma-mass spectrometry. The analysis results show that Li is mainly enriched at the bottom and top of the aluminiferous rock series, and the Li content at the top is higher (615.98–3289.98 ppm). Li content is positively correlated with Mg and Fe content, indicating that chlorite is a potential Li-bearing mineral. K content of <10,000 ppm, K content is positively correlated with Li content, indicating that illite may also be a Li-bearing mineral. Kaolinite, transformed from montmorillonite, may also have a high Li content. Ga content is always positively correlated with Al content, indicating that Ga mainly occurs in diaspores. Bauxite has similar Nb/Ta and Zr/Hf ratios to the underlying Hanjiadian Formation shale, as well as the same positive Ce anomalies (negative anomalies in Huanglong Formation), indicating that the ore-forming material of Danping is primarily derived from the underlying Hanjiadian Formation.

Optimizing lithium-silver alloy phases for enhanced energy density and electrochemical performance

Lithium (Li) metal batteries though with high energy density are still facing issues like Li dendrite growth, dead Li formation, and thick solid electrolyte interphase (SEI) formation, hindering their long-term stability. Recently, Li-Ag alloys have been reported to potentially address these challenges possibly due to their superior conductivity, lithiophilicity, and mechanical stability. In the pursuit of high-energy-density batteries, Li-Ag alloys typically employ a high Li content phase (γ1). In this study, we applied density functional theory (DFT) calculations to compare the thermodynamic stability, Li adsorption, and Li diffusion of Ag-rich Li-Ag alloy within the γ1 phase (AR-γ1), Ag-poor Li-Ag alloy within the γ1 phase (AP-γ1), and pure Li. AR-γ1 showed better thermodynamic stability and improved Li adsorption and diffusion properties compared to AP-γ1 and pure Li. Electrochemical tests further confirmed the advantages of AR-γ1 in terms of electrode kinetics and cell stability compared to AP-γ1 and pure Li. Our study offers guidance for the selection of the most suitable Li-Ag alloys that can be utilized in high-energy-density lithium batteries.