Li Sources Research Articles

A comparative study of LiTa2PO8 ceramics prepared with different lithium sources

In advancing lithium-ion batteries, solid electrolytes like LiTa2PO8, a Li-ion conductor with high bulk conductivity (~10−3 S/cm), show promise for all-solid-state battery technology. Here, we investigate the impact of different Li sources and their excess on the structural, microstructural and electrical properties of LiTa2PO8 ceramics. Employing diverse characterization techniques, including XRD, MAS NMR, TMA, SEM/EDS, IS, DC potentiostatic polarization, and density measurements, we unveil significant impact of the source of lithium ions and its excess on electrical properties. The sample without excess LiNO3 source exhibited the highest σtot = 5.2×10−4 S/cm at 30°C. Notably, the grain conductivity remained constant at ca. 3 mS/cm, irrespective of the chosen lithium source and excess. The microstructural analysis uncovered correlations between variations in total ionic conductivity and changes in the nature and concentration of secondary phases. Additionally, it revealed the influence of the arrangement of grains affecting the grain boundaries and porosity regions.

Optimized and nonTi-site doped synthesis of lithium titanate by mechanochemical method

The Li2CO3-ammonia-ballmilling synthesis system of Li4Ti5O12 (LTO) was optimized and doped Li and O by theirs adjacent elements Mg and F respectively. By adjusting the ballmilling parameter, the distribution of Li and Ti sources, the hydrolysis rate and different nucleophilic / electrophilic hydrolysis path of Ti, and the interaction between Li and Ti species can be effectively controlled. The temperature programmed calcination is beneficial to the formation of the middle state (Li2TiO3), obtaining the high quality LTO. Mg and F doping can further optimize the hydrolysis and condensation degree of Ti source, the number of crystal nucleus and the particle size. Therefore, the initial first discharged capability of Mg doped LTO and F doped LTO reach to 152.4 mAh/g and 163.1 mAh/g at 5 C respectively, corresponding 32.4 % and 41.7 % enhancing compared to LTO (115.1 mAh/g). Moreover, the discharge voltage of LTO-Mg decreases from 1.5 V to 1.3 V.

Operando-XRD of Electrochemical Reactors for Selective Li+ Extraction from Brines and Seawater

In times of rising demand of Li for use in Li-ion batteries (LIBs), and ensuring its supply for aluminum electrolysis, ultralight alloys, optics, synthesis, nuclear research, and pharmaceuticals, it is essential to simplify the processing of Li sources in a sustainable manner. Current extraction from ores is complex and requires large energy input while generating high amounts of waste. This causes the danger of making Li a limited resource and even more expensive.[1] A new promising way is the electrochemical extraction of Li by desalination batteries (DBs) from brines or seawater[2]. Thereby, selective extraction of ions can be promoted by the chemistry of the electrode material, e.g., by using FePO4. To further enhance the selectivity, potentiostatic application proved to be useful[3]. DBs are superior to other extraction methods in terms of energy efficiency, and waste generation. Still, varying Li+ concentrations in brines[1b], competitive intercalation of other cations with similar size - especially Na+ [2] -, and degradative effects of anions[4], H2O, and O2 [5] are major challenges to overcome for DBs with FePO4.In this contribution, we focus on the selective extraction of Li+ using FePO4 electrodes by specifically-designed multi-step potentiostatic application. Results are shown for salt solutions containing a mixture of Na+/Li+, and artificial seawater. It is vital to understand the atomic-scale processes so that the electrodes, and electrochemical parameters can be optimized. Therefore, we used operando high-energy X-ray diffraction (HEXRD) microscopy to investigate the crystal structure of FePO4 during the electrochemical process. The experiments showed that the energy barrier for Na+ (de)intercalation was higher than that of Li+ during galvanostatic cycling, i.e., FePO4 is selective for Li+. Using a multi-step potentiostatic procedure, the (de)intercalation process could be enhanced, as evident from our HEXRD results and simultaneous conductivity measurements. Our tentative interpretation is that Li+ is highly selectively (de)intercalated, although electrochemical signatures hinted on a two-step process during deintercalation, which may indicate the intercalation of Na+. To selectively deintercalate the remaining Na+ over Li+, we further optimized the applied potentials. During galvanostatic cycling in artificial seawater, the (de)intercalation potentials were at more positive and more negative potentials, respectively, likely caused by the variety of cations. We expect that our results contribute to the design of high-performance DBs and inspire the exploration of further systems based on our proposed multi-step process.

Retrieving lost Li in LIBs for co-regeneration of spent anode and cathode materials

Direct regeneration of spent Li-ion battery electrode materials has garnered considerable attention due to its streamlined procedure, low energy consumption, and high economic viability. Typically, an Li source is required to address the vacant Li defects in spent cathodes for regeneration, while the removal of residual Li is crucial for regenerating spent anodes. Here, given our discovery that approximately 65 % of the residual Li in spent graphite demonstrates reactivity with water, we propose a straightforward water extraction method for purifying and regenerating spent graphite anode. By carefully controlling the concentrations of OH- and Li+ ions in the obtained Li-rich solution, it can be directly used to relithiate spent NCM cathodes. In this method, Li+ ions lost from the cathode during electrochemical cycling were reintroduced back into the cathode via aqueous relithiation, eliminating the need for additional Li sources to repair the Li deficiencies in spent cathode, effectively reducing recycling costs and minimizing the environmental impact associated with raw materials. The regenerated NCM cathode and graphite anode demonstrated specific capacities of 163 mAh/g and 386 mAh/g at a rate of 0.1C, respectively, both reaching the performance levels of pristine materials. Importantly, compared to traditional direct recycling methods, the Li-retrieving regeneration method reduced greenhouse gas emissions by 16 %, energy consumption by 17 %, water consumption by 17 %, and overall recycling costs by 12 %.

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.

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.

Closed-loop resynthesis of LiNiCoAlO2 cathode active materials from the industrial leachate of spent li-ion batteries

The burgeoning electric vehicle market is significantly leading to a substantial increase in spent lithium-ion batteries (LIBs), emphasizing the need for efficient recycling to address raw material supply challenges. The resynthesis of cathode active materials, one of emerging efficient LIB recycling methods, refers to the synthesis of precursors from the leachate of spent LIBs without the separation of each element. While the resynthesis of LiNixCoyMnzO2 (NCM) from the Mn-rich industrial leachate of spent LIBs becomes popular nowadays, there is no practical approach for the resynthesis of LiNixCoyAlzO2 (NCA) from the industrial leachate. For the resynthesis of NCA, an additional purification step of solvent extraction with di(2-ethylhexyl) phosphoric acid for Mn removal is necessary. NCA is resynthesized from the Mn-removed leachate, after adjusting the Ni:Co ratio of precursors and sintering with Li and Al sources. While the initial discharge capacity of resynthesized NCA is slightly reduced to the electrochemically inactive impurities of Mg and Mn, its rate capability and cyclability are improved compared to pristine NCA from virgin materials. The effects of major impurities of Mg and Mn on the crystal structure and electrochemical properties of resynthesized NCA are further elucidated. Whereas the controlled Mg/Mn doping positively impacts both rate capability and cyclability, excessive Mn leads to degraded cyclability. Overall, our study expands the scope of resynthesis process of cathode active materials from spent LIBs, highlighting the intricate role of impurities and their impact on LIB performance.

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.

Controllable Interface Engineering for the Preparation of High Rate Silicon Anode

AbstractSilicon (Si) is considered to be the promising candidate anode for the next generation of high‐energy‐density batteries. However, the poor initial coulombic efficiency (ICE) and rate performance severely hinder its commercial development. Here, fully exploits the 2D structure of photovoltaic silicon waste (PV‐WSi), combining with the advantage of controllable depositing layers offered by fluidized bed atomic layer deposition (FBALD), to simultaneously achieve high ICE and highrate performance of Si‐based anodes. The characteristic of Li+ embedding vertically into the plane direction of the 2D sheet‐like structure of PV‐WSi helps shorten the diffusion distance, alleviating the pulverization problem caused by volume expansion. FBALD is utilized to controllably deposit Li2O (≈1 nm) and TiO2 (≈4 nm) layers to compensate for the loss of Li sources, further suppressing the volume expansion of Si and isolating the side reactions between Si and electrolyte. The prepared Si@Li2O@TiO2 demonstrates ultrahigh ICE (90.9%) and outstanding rate performance (>900 mAh g−1 at a rate of 20 A g−1). Full cells with the Si@Li2O@TiO2 anode and LiFePO4 cathode deliver a stable capacity of 100 mAh g−1 after 300 cycles at 0.5 C. This work provides new ideas for the development of high ICE, high‐rate Si‐based anodes based on low‐cost photovoltaic waste.

Boosting Cathode Activity and Anode Stability of Lithium-Sulfur Batteries with Vigorous Iodic Species Triggered by Nitrate.

Lithium-sulfur (Li-S) battery with a sulfurized polyacrylonitrile cathode is a promising alternative to Li-ion systems. However, the sluggish charge transfer of cathode and accumulation of inactive Li on anode remain persistent challenges. An advanced electrolyte additive with function towards both cathode and anode holds great promise to address these issues. Herein, we present a new strategy to boost sulfur activity and rejuvenate dead Li simultaneously. In the polar electrolyte containing I2-LiNO3 additives, I3 -/IO3 - are triggered significantly by the reaction between NO3 - and I- ions. The I3 -/IO3 - are reactive to insulated Li2S product of cathode and inactive Li on anode, thus accelerating the conversion reaction of sulfur and recovering Li sources back to battery cycling. The in situ/ex situ spectroscopic and morphologic monitoring reveal the crucial role of iodine in promoting Li2S dissociation and inhibiting dendritic Li growth. With the modified electrolyte, the symmetric Li||Li cells deliver a lifespan of 4000 h with an overpotential less than 12 mV at 0.5 mA cm-2. For Li-S cells, 100 % capacity retention up to thousands of cycles and enhanced rate capability are available. This work demonstrates a feasible strategy on electrolyte engineering for practical applications of Li-S batteries.

Boosting Cathode Activity and Anode Stability of Lithium–Sulfur Batteries with Vigorous Iodic Species Triggered by Nitrate

AbstractLithium–sulfur (Li−S) battery with a sulfurized polyacrylonitrile cathode is a promising alternative to Li‐ion systems. However, the sluggish charge transfer of cathode and accumulation of inactive Li on anode remain persistent challenges. An advanced electrolyte additive with function towards both cathode and anode holds great promise to address these issues. Herein, we present a new strategy to boost sulfur activity and rejuvenate dead Li simultaneously. In the polar electrolyte containing I2−LiNO3 additives, I3−/IO3− are triggered significantly by the reaction between NO3− and I− ions. The I3−/IO3− are reactive to insulated Li2S product of cathode and inactive Li on anode, thus accelerating the conversion reaction of sulfur and recovering Li sources back to battery cycling. The in situ/ex situ spectroscopic and morphologic monitoring reveal the crucial role of iodine in promoting Li2S dissociation and inhibiting dendritic Li growth. With the modified electrolyte, the symmetric Li||Li cells deliver a lifespan of 4000 h with an overpotential less than 12 mV at 0.5 mA cm−2. For Li−S cells, 100 % capacity retention up to thousands of cycles and enhanced rate capability are available. This work demonstrates a feasible strategy on electrolyte engineering for practical applications of Li−S batteries.

Over‐ and Hyper‐Lithiated Oxides as Sacrificial Cathodes for Lithium‐Ion Batteries

AbstractBy incorporating sacrificial lithium (Li) sources during electrode fabrication, researchers aim to address the challenge of initial capacity loss due to the formation of a solid electrolyte interphase layer during the early cycles of lithium‐ion batteries (LIBs). This research contributes to the augmentation of Li+ inventory within the electrode to compensate for the irreversible loss of Li+, thereby enhancing the reversibility and cycling performance of LIBs. There are various types of pre‐lithiation additives; however, this perspective specifically discusses over‐ and hyper‐lithiated oxide materials. Within these oxides, research directions are characterized by contrasting approaches aimed at either enhancing the reversibility or inducing the irreversibility of these materials. Intriguingly, both opposing approaches align with the common objective of increasing the energy density of LIBs by providing surplus Li+ to compensate for irreversible Li+ consumption. From this perspective, a concise overview of diverse pre‐lithiation methodologies is provided and the reaction mechanisms associated with over‐ and hyper‐lithiated oxides as sacrificial cathode additives for pre‐lithiation are investigated. Subsequently, strategies to modulate the electrochemical properties of these oxides for practical use in sacrificial cathodes are briefly explored. Following this, discussions are carried out and perspectives on research that adopts the aforementioned contrasting directions are presented.

Controls on lithium content of oilfield waters in Texas and neighboring states (USA)

The amount of lithium (Li) required to support the energy transition underscores the need to develop Li sources beyond the traditional hard-rock mining and surface continental brines. The objective of this study was to explore the potential for Li production from oilfield waters in the U.S. Gulf Coast region. Data on Li concentrations were obtained from ~2450 formation water samples taken in states along the greater Gulf Coast (NM, TX, OK, LA, AR, and MS). The dataset contains geochemical analyses that spans >70 years, including the USGS database (v2.3), compilation of recent data previously published by the authors, analyses from recently collected samples and from archived samples, and data from U.S. Bureau of Mines reports.Aqueous Li distribution is lognormal, typical of trace elements, with background levels in the 0–20 mg/L range. High concentrations (≥80 mg/L) are restricted to some intervals at certain locations: Jurassic Smackover Formation, a well-known brine deposit in Arkansas (300+ mg/L Li), but also along the Gulf Coast in Texas, Louisiana, and Mississippi (several samples ≥100 mg/L Li); Permian and Pennsylvanian Granite Wash in the Anadarko Basin of Texas (several samples >100 mg/L Li) (not confirmed); and Cretaceous Edwards Formation of South Texas (several samples ≥100 mg/L Li). Genetic models for Li enrichment are lacking, but high Li seems to be related to the noted fact that Li concentrations increase with depth and with total dissolved solids. Other common characteristics of high-Li brines in the Gulf Coast are high K, Ca, and B, which reflect water-rock interactions, presence of major faults, and association with higher permeability intervals that can spread Li-bearing fluids. Host rocks for high-dissolved Li brines commonly are carbonates, possibly because of their limited sorption opportunities. Close connection to an igneous basement or to a depositional environment that supported accumulation of surface continental brines does not seem to be required.

Recent Research Progress on All-Solid-State Mg Batteries

Current Li battery technology employs graphite anode and flammable organic liquid electrolytes. Thus, the current Li battery is always facing the problems of low energy density and safety. Additionally, the sustainable supply of Li due to the scarce abundance of Li sources is another problem. An all-solid-state Mg battery is expected to solve the problems owing to non-flammable solid-state electrolytes, high capacity/safety of divalent Mg metal anode and high abundance of Mg sources; therefore, solid-state electrolytes and all-solid-state Mg batteries have been researched intensively last two decades. However, the realization of all-solid-state Mg batteries is still far off. In this article, we review the recent research progress on all-solid-state Mg batteries so that researchers can pursue recent research trends of an all-solid-state Mg battery. At first, the solid-state electrolyte research is described briefly in the categories of inorganic, organic and inorganic/organic composite electrolytes. After that, the recent research progress of all-solid-state Mg batteries is summarized and analyzed. To help readers, we tabulate electrode materials, experimental conditions and performances of an all-solid-state Mg battery so that the readers can find the necessary information at a glance. In the last, challenges to realize the all-solid-state Mg batteries are visited.

Mechanistic Study of Lithium Electrodeposition Using Dynamic Electrochemical Impedance Spectroscopy

Lithium metal batteries have increased energy density over standard graphite-based Li-ion anodes. However, Li metal anodes have difficulty forming stable passivation layer (called solid electrolyte interphase, SEI) leading to poor use of Li inventory. That is, LI metals require larger cathode loading, which reduces the energy density gain. A holistic approach to Li anode incorporation includes electrolyte design, mechanism understanding, and battery engineering. A factor that has not been fully appreciated is the nature of the Lithium metal itself, namely its SEI before incorporation into the battery device may affect the subsequent SEI formation. Here, we present a mechanistic study on lithium SEI formation on various lithium sources, as well as the Li cycling.We utilized dynamic impedance spectroscopy (dEIS) to probe the formation and evolution of the SEI during Li cycling of various Li sources. dEIS superimposes a multisine waveform atop the dc stimulus signal. After applying a sliding window FFT protocol that takes the complex ratio of the measured potential and current signals time-resolved complex impedance can be obtained. We will discuss the differences between the Li cycling profiles using Lipon (a glassy solid electrolyte) and a liquid electrolyte. We will relate the differences in cycling performance, particularly the SEI evolution to the surface chemistry of the as-received Li metal source.The US Department of Energy's Energy Efficiency and Renewable Energy Vehicles Technologies Office provided funding for this work under the US-German Cooperation on Energy Storage: Lithium-Solid-Electrolyte Interfaces program.

The Impact of Li Surface Heterogeneity and Morphology on Performance in Solid-State Batteries

Solid-state Li metal batteries have the potential to enable both fast charging and more than a 30% increase in energy density. Two of the most pervasive and limiting challenges in these materials are the interface between the Li metal and the solid electrolyte and the formation of Li filaments that penetrate the solid electrolyte leading to cell shorting. Currently, most efforts to solve these problems are focused on solid electrolytes. Here we present our work investigating the Li side of the equation. This work compares four thin Li sources (<40 µm), three rolled Li from commercial suppliers, and a fourth prepared in-house using thermal evaporation. Using X-ray photoelectron spectroscopy (XPS) and attenuated total internal reflection infrared spectroscopy (ATIR), we determined that the surface layers on these different Li films varied significantly in composition and thickness. Subsequent electrochemical testing of these films in liquid, polymer, and ceramic solid electrolytes, showed that variation in the surface thickness and chemistry significantly impacted the interfacial resistance. Furthermore, an analysis of cell failure due to shorting led to the clear conclusion that in addition to the surface contamination, the Li microstructure also had a significant impact in determining when failure will occur. Acknowledgments: Simon Thompson and the DOE EERE Vehicle Technology office Battery Material Research Program for funding supporting this work.

Lithium enrichment processes in sedimentary formation waters

Reservoirs exploited for oil, gas, or geothermal energy in sedimentary basins may represent an alternative lithium resource to salars and hard rocks. Similarities in the geochemical characteristics of the basins were searched using a database of 2400 water analyses available from more than 40 sedimentary basins worldwide, notably a selection of representative geochemical trends on 13 basins. The objective was to understand better the factors controlling Li concentrations and the potentiality of such basins for the Li-recovery. Considering LiCl and MgCl relationships, major cation (Na/K, Na/Ca) and halogen (Cl/Br) ratios, Li concentrations are monitored in several basins by mixing processes between low salinity recharge waters, seawater and brines. Lithium concentrations span three orders of magnitude in brines between evaporated seawater that has passed saturation with halite and a particularly Li-enriched pole. In the latter, significant Li-enrichment is obtained when brines are primary, in equilibrium with halite, and then enriched in Li through fluid-rock interaction processes. Li-rich lithologies such as volcanic rocks, Li-enriched clay formations, or Li-phyllosilicates dispersed in siliciclastic rocks or the underlying crystalline basement probably act as the primary Li sources. Finally, Li extraction is promoted by the rise in temperature, which explains the high Li concentrations in the waters of geothermal systems. Therefore, favourable reservoirs for Li-rich brines are characterised by a brine collection from evaporites during tectonic events, such as compressive events or salt tectonics, at a relatively short distance from the present reservoir. They must be preserved from convection and surface water ingress via recharge zones to prevent dilution and Li depletion.

Lithium enrichment in the Salar de Diablillos, Argentina, and the influence of Cenozoic volcanism in a basin dominated by Paleozoic basement

Salars with lithium-rich brines are a characteristic feature of the Central Andes, but knowledge about the main sources of lithium and the mobilization processes of lithium in the salar deposits is still incomplete. This work focuses especially on the Salar de Diablillos (southern Puna) as part of a larger area that includes the neighboring Salar Centenario and Salar de Ratones. Building on the ability of Li as a tracer of silicate weathering, we investigate the Li content and isotope composition of samples from the depocenter and catchment of the Diablillos basin (3-D) and conduct a surface reconnaissance in the Centenario and Ratones depocenters to identify the key metallogenic processes. Radiogenic Sr and Nd isotope compositions are also provided to discriminate the main local Li sources. The isotope data in all three depocenters show that most of the Li in the brines and evaporite deposits are derived from Cenozoic volcanic rocks, despite the dominance of the Paleozoic basement in the catchment. In the Centenario and Ratones depocenters, near-surface chemical weathering appears to be the dominant Li mobilization process. In contrast, hydrothermal mobilization of Li also plays a role in the Salar de Diablillos, possibly related to the presence of a fractured basement with pressure zones and artesian conditions in the aquifer at depth. These fluids also show a larger element contribution from the basement.

Rational synthesis of high-performance Ni-rich layered oxide cathode enabled via probing solid-state lithiation evolution

Lithium (Li)-ion batteries using nickel (Ni)-rich layered oxide cathode have been pursued with interest due to high practical energy density. A fundamental understanding of the reaction pathways and structural evolution of the solid-phase synthesis of these materials is crucial for their rational design and process development for mass production. In this work, structural evolution during solid-state synthesis was traced via in situ technique, with a particular emphasis on the lithiation reaction and migration of transition metal (TM) ions. The sintering process is governed by the competitive relationship of decomposition and lithiation reactions, which can be regulated through temperature windows. Controlling the melting point of the Li sources, as well as their affinity to cathode precursors, is highly desired to maintain the layered ordering of TM ions throughout the whole synthesis process, which simplifies the manufacturing process and improves the quality of the manufactured cathode material.

A Machine Learning-Based Study of Li+ and Na+ Metal Complexation with Phosphoryl-Containing Ligands for the Selective Extraction of Li+ from Brine

The growth of technologies concerned with the high demand in lithium (Li) sources dictates the need for technological solutions garnering Li supplies to preserve the sustainability of the processes. The aim of this study was to use a machine learning-based search for phosphoryl-containing podandic ligands, potentially selective for lithium extraction from brine. Based on the experimental data available on the stability constant values of phosphoryl-containing organic ligands with Li+ and Na+ cations at 4:1 THF:CHCl3, candidate di-podandic ligands were proposed, for which the stability constant values (logK) with Li+ and Na+ as well as the corresponding selectivity values were evaluated using machine learning methods (ML). The modelling showed a reasonable predictive performance with the following statistical parameters: the determination coefficient R2= 0.75, 0.87 and 0.83 and root-mean-square error RMSE = 0.485, 0.449 and 0.32 were obtained for the prediction of the stability constant values with Li+ and Na+ cations and Li+/Na+ selectivity values, respectively. This ML-based analysis was complemented by the preliminary estimation of the host–guest complementarity of metal–ligand 1:1 complexes using the HostDesigner software.