Electrochemical Extraction Of Lithium Research Articles

Revealing the functional relationship between manganese dissolution potentials and lithium concentrations with diffusion coefficient for lithium intercalation in λ-MnO2 electrode

Electrochemical redox lithium extraction (ELE) with LiMn2O4/λ-MnO2 redox couple, stands out as the most prospective technology for efficient and selective lithium extraction from the salt lake brines owing to the high lithium intercalation capacity, selectivity, and recovery rate. However, the decreasing Li+ concentration induced electrode polarization, especially, at low concentrations, and inappropriately applied potentials can significantly accelerate manganese dissolution (MD). While no correlational research has established the relationship between the manganese dissolution potential (EMD) and Li+ concentration gradient. Herein, the inversely proportional relationship between EMD and the lithium concentration is first revealed through steady-state diffusion coefficients. This research sheds light on the MD mechanism at different lithium concentration gradients and lays the foundation for the industrial application of electrochemical lithium extraction with LiMn2O4/λ-MnO2 redox couple from salt lake brines.

The Technologies of Electrochemical Lithium Extraction Process from Lithium-Containing Solutions

The Technologies of Electrochemical Lithium Extraction Process from Lithium-Containing Solutions

Self-Oxidated Hybrid Conductive Network Enables Efficient Electrochemical Lithium Extraction Under High-Altitude Environment.

The electrochemical deintercalation method has been considered as an effective way to address the demand for lithium resources due to its environmental friendliness, high selectivity, and high efficiency. However, the performance of electrochemical lithium extraction is closely dependent on the electrode material and needs to be compatible under plateau environments with high-altitude and low-temperature. Herein, an in situ self-oxidation method is conducted to construct a hybrid conductive network on the surface of LiFePO4 (LFP-HN). The introduction of a hybrid conductive network enhanced the interfacial electron/lithium-ion transfer. In addition, structural stability is strengthened through suppressing the intercalation of impurity cations. Consequently, the LFP-HN delivered extremely high lithium extraction capacity (27.42mg g-1), low energy consumption (4.91Wh mol-1), and superior purity (91.05%) in Baqiancuo real brine (4788 m, -10°C). What's more, LFP-HN-based large-scale prototypes are constructed and operated at Baqiancuo, which is calculated to extract 25kg Lithium Carbonate Equivalent per cycle (4.55h, 100 pairs of plates). Based on the excellent performance, the modification strategy developed in this work can be a promising solution for industrial lithium extraction under high-altitude environment.

Triple synergistic effects of bismuth doping in spinel-LiMn2O4: A path to high-performance electrochemical lithium extraction from salt-lake brine

The electrochemical extraction of lithium-ion from salt-lake brine has attracted significant global interest due to the rising requirement for lithium resources. The electrochemical extraction system based on LiMn2O4 has emerged as one of the most promising methods for commercial lithium extraction. However, the dissolution of manganese in LiMn2O4 material, caused by the Jahn-Teller effect, poses a significant obstacle to achieving large lithium extraction capacity and long lifespan simultaneously. In this study, we addressed the issue by incorporating Bi3+ into the material. The resulted LMBO material displays a truncated octahedral morphology, with {100} crystal faces facilitating Li+ diffusion. Additionally, Bi3+-doping inhibits the Jahn-Teller effect and expands the Li+ diffusion pathway, thereby, enhancing the stability and Li+ diffusion rate of LMO. In particular, LMBO-2 material exhibits an excellent lithium ion diffusion rate of 2.03 × 10−9 cm2·s−1, and demonstrates outstanding Li+ release efficiency, which reaches 26.46 mg·g−1 per cycle with an average energy consumption of 2.04 Wh·mol−1 in the 30 mmol⋅L−1 simulated salt-lake brine. In simulated Zabuye brine solution, LMBO//Ag system displayed an admirably release capacity of 26.17 mg·g−1 characterized by an ultra-low Li/Na ratio, with Li/Na ratio in recovery solution reaching as high as 0.54. These significant findings advance practical applications of LiMn2O4 in brine lithium extraction processes.

Photothermal-enhanced ion transport for efficient electrochemical lithium extraction at low temperatures

The demand for lithium (Li) resources is booming due to the widespread applications of Li-ion batteries recently. Electrochemically extracting lithium from brines is a promising approach to address the shortage of Li resources. However, when working at low temperatures, which are inevitable in frigid salt lakes, the performance is severely deteriorated due to depressed transport kinetics. Herein, we addressed this issue by constructing a new electrochemical lithium extraction system using polypyrrole-coated FePO4 as the electrode material, which exhibits superior performance at low temperatures due to photothermal effect of polypyrrole. At an ambient temperature of 5 °C and irradiated with sunlight, this system achieved a lithium intercalation capacity of 5.84 mmol g−1 (2.72 times higher than that without solar irradiation) at an extraction rate of 5.92 mmol g−1 h−1 from a 15 mM LiCl solution, and a selectivity of 124 towards Li over Mg. After 5000 cycles of continuous operation, the system still retained 81 % of its initial capacity at a current density of 50 A m−2. The proposed photothermal-enhanced electrochemical lithium extraction system has great application potential for lithium extraction from brine at low-temperature regions.

Electrochemical lithium extraction from high Mg/Li brine using LiMn2O4-Zn mixed-Ion battery

In China, 80 % of lithium resources are in the salt lakes of the Tibetan Plateau, although the Mg2+/Li+ ratios in them are too high, limiting the development of China’s lithium extraction industry from the salt lakes. This study investigates the potential of the LiMn2O4-Zn cell system for lithium extraction from brines with high Mg2+/Li+ ratios. The system demonstrates excellent selectivity for Li+ and efficiently extracts Li+ even in brines with Mg2+/Li+ ratios as high as 100:1 (wt%). The system operates stably at various brine concentrations, particularly in high-salinity environments. The study also investigates the kinetic performance of the LMO-Zn system, revealing optimal performance at high Li+ concentrations and moderate current densities. The LiMn2O4-Zn cell system presents a promising approach for lithium extraction from brines, offering high selectivity, reversibility, and adaptability.

Overcoming polarization and dissolution of manganese-based electrodes to enhance stability in electrochemical lithium extraction

The Mn dissolution issue in manganese-based materials (LMO) represents one of the most challenging barriers to further commercial development of electrochemical lithium extraction, which is an efficient and clean way of extracting Li from liquid resources. Here, by leveraging the advantages of composite materials, a novel combination of reduced graphene oxide (rGO) and sulfonated ionic polymers (Nafion) is introduced to relieve the issues of electrode polarization and manganese dissolution, critical factors limiting the durability of LMO electrodes. By modifying with rGO to enhance electronic conductivity and surface characteristics, and capturing dissolved Mn2+ through Nafion, the modified electrode showed significant improvement in cycling stability and lithium adsorption capacity. Experimental results confirm that this synergistic approach effectively mitigates polarization effects and controls disproportionation reactions, thereby enhancing the stability of the lithium extraction process, revealing a notable increase in electrode capacity retention from 79.04 % to 94.64 % after 30 cycles. Additionally, through DFT calculations and XPS analysis, the effectiveness of the manganese capture strategy is validated. This work presents an effective new strategy to extend the lifespan of manganese-based electrodes and enhance their adsorption performance.

Co-doping induced Mn-vacancy LiMn2O4 based membrane electrode for lithium extraction by electrochemically switched ion permselective process

LiMn2O4 (LMO) is considered an effective electroactive material for electrochemical lithium extraction from aqueous solutions. However, the stability issue limits its practical application. Herein, Co-doping induced Mn-vacancy LiMn2O4 (LCMO) powders were synthesized by a high-temperature solid-phase method, which were further applied to prepare an electrochemical permselective membrane electrode for selective lithium-ion extraction. Physicochemical characterizations combining with density functional theory (DFT) calculations revealed that Co-doping at 8a site will induce the formation of Mn vacancies in LMO, which can reduce the content of easily dissolutive trivalent Mn (Mn3+) and lower the Li+ migration energy barrier. As a result, the Li+ permeation flux of optimized LCMO-0.04 (Co: Mn = 0.04: 1.96) based membrane electrode (156.809 mmol·m−2·h−1) was increased by 85.65 % compared to that of LMO-based one (84.461 mmol·m−2·h−1) in an electrochemically switched ion permselective (ESIP) system. The selectivity factors of Li+/ Na+, Li+/Mg2+, Li+/ K+ for the LCMO-0.04 based membrane electrode were up to 10.06, 11.69, and 15.19, which were about twice as high as those for LMO membrane based one. After 1000 circles of cyclic voltammetry (CV) tests, the CV area of the LCMO-0.04 based membrane electrode maintained 91.59 % of the initial value, demonstrating remarkable electrochemical stability.

Layered Double Oxide as a Cl− Selective Anode for High-Performance Electrochemical Lithium Extraction

Layered Double Oxide as a Cl⁻ Selective Anode for High-Performance Electrochemical Lithium Extraction

Identifying critical features of iron phosphate particle for lithium preference

One-dimensional (1D) olivine iron phosphate (FePO4) is widely proposed for electrochemical lithium (Li) extraction from dilute water sources, however, significant variations in Li selectivity were observed for particles with different physical attributes. Understanding how particle features influence Li and sodium (Na) co-intercalation is crucial for system design and enhancing Li selectivity. Here, we investigate a series of FePO4 particles with various features and revealed the importance of harnessing kinetic and chemo-mechanical barrier difference between lithiation and sodiation to promote selectivity. The thermodynamic preference of FePO4 provides baseline of selectivity while the particle features are critical to induce different kinetic pathways and barriers, resulting in different Li to Na selectivity from 6.2 × 102 to 2.3 × 104. Importantly, we categorize the FePO4 particles into two groups based on their distinctly paired phase evolutions upon lithiation and sodiation, and generate quantitative correlation maps among Li preference, morphological features, and electrochemical properties. By selecting FePO4 particles with specific features, we demonstrate fast (636 mA/g) Li extraction from a high Li source (1: 100 Li to Na) with (96.6 ± 0.2)% purity, and high selectivity (2.3 × 104) from a low Li source (1: 1000 Li to Na) with (95.8 ± 0.3)% purity in a single step.

Multistage regulation of LiMn2O4 electrode for electrochemical lithium extraction from salt-lake

The sustainable development of future energy relies significantly on the abundant lithium resources present in salt-lake brines. LiMn2O4 (LMO) electrochemical Li+ pump has garnered substantial attention due to its capacity to efficiently extract lithium resources from aqueous solutions with minimal energy consumption. However, the industrial application of LMO electrodes is often limited by Mn dissolving during cycles, as well as the complex and variable brine environment. To address these challenges, this study conducted a multistage regulation of LMO electrodes. Originally, the sol-gel technique was used to prepare CePO4 loading LMO. Due to CePO4 rivet load reforming LMO surface charge, the best-performing 1 wt% CePO4-loaded LMO exhibited a remarkable capacity retention rate of 83.8 % after 30 cycles. Subsequently, a comprehensive hydrophilic modification was applied to the entire electrode. 20%PAA-1CP-LMO//Ag system displayed an admirably release capacity of 24.7 mg·g−1 in Zabuye real brine characterized by an ultra-low Li/Na ratio, with Li/Na ratio in recovery solution reaching as high as 0.62.

The regeneration process of FePO4 in electrochemical lithium extraction: The role of alkali ions

The rapid expansion of lithium battery applications has resulted in a shortage of lithium resources, prompting researchers to focus on the electrochemical extraction of lithium from water resources using FePO4 as the host material. However, a large amount of alkali metal impurity ions in brine leads to irreversible capacity loss, limiting the industrial application of FePO4 materials in lithium extraction. The mechanism of alkali metal ions’ influence on FePO4 materials remains unclear. To address this issue, the quaternary phase diagram of FePO4-LiFePO4-NaFePO4-KFePO4 and the diffusion barriers of lithium/sodium ions in FePO4 were obtained for the first time based on the theoretical calculation of density functional theory (DFT). DFT and X-ray diffraction (XRD) refinement revealed that the inability to remove Na2/3FePO4 from the FePO4 is a critical issue affecting electrode recyclability. An innovative electrode regeneration process was proposed to enhance the lifespan of FePO4 material. The Na2/3FePO4 impurity was converted to LiFePO4 using K2S2O8 abstersion and 0.1 mol/L LiCl lithiation regeneration process. After five rounds of regenerations, the total lithium extraction of the material could still reach 80.18 % of the extraction of the brand-new electrode, demonstrating the multiple reuses of the host material and cost savings. These innovative discoveries can advance the industrial application of electrochemical lithium extraction from FePO4 electrode materials.

Continuous Flow‐By Electrochemical Reactor Design for Direct Lithium Extraction from Brines

AbstractThe demand for lithium is expected to increase significantly in the next few years, mainly due to the energy transition in the mobility sector. To electrify the entire global transportation system, it is necessary to have access to a wide variety of lithium deposits to ensure resource sovereignty and sufficient supply to meet demand. For this reason, much effort has recently been invested in developing technologies for direct lithium extraction (DLE) from brines. In this work, a membrane‐based continuous flow‐by reactor for the electrochemical extraction of lithium from brine with a LiMn2O4/λ‐MnO2 system has been studied. A zoned reactor was proposed in which the current density and electrode mass loading gradually decrease along with the depletion of lithium in the brine, obtaining an average electrode capacity of 80 mAh/g throughout three different reactor sections. The limiting Reynolds number was determined for the dilute lithium segment of the reactor to avoid mass transport limitations, with brine concentration equal to Li 3 mM and Na 1.3 M. A homogeneous cycle time was achieved for the three reactor zones and their associated average energy consumption was determined, ranging from 3.9 Wh/mol Li to 9.5 Wh/mol Li.

Progress in Electrochemical Extraction of Lithium from Seawater

Progress in Electrochemical Extraction of Lithium from Seawater

Go-encapsulated La-doped lithium manganese oxide assemblies to enhance lithium extraction performance in capacitive deionization

The electrochemical lithium extraction technique from brine has emerged as a key strategy in addressing the issue of lithium resource scarcity. Lithium manganese oxide (LMO) stands out as a typical lithium-ion selective material. Nevertheless, its lithium extraction application is restricted by inadequate conductivity and limited cycling stability. In this report, through a simple electrostatic self-assembling method, a 3-dimensional (3D) GO/La-LMO hybrid was fabricated wherein La-doped LMO (La-LMO) was enveloped by graphene oxide (GO) nanosheets. The resultant GO/La-LMO exhibited a significantly improved electrochemical behavior with fast Li+ diffusion rate and high conductivity. The GO/La-LMO hybrid demonstrated outstanding selectivity for the electrochemical intercalation/de-intercalation of Li+. As a Li+-selective cathode in capacitive deionization (CDI) device, the GO/La-LMO electrode achieved a high Li+ adsorption capacity of 1.33 mmol g−1 (10 mM LiCl) and superior selectivity with a separation factor of 126 (Mg2+/Li+ = 30, molar ratio) in Mg2+/Li+ mixed solution. The Li+ extraction percentage reached 80.4 % in the simulated salt-lake brine. Crucially, the GO/La-LMO electrode substantiated prominent structural stability and low Mn dissolution over 100 cycles, attributed to the synergistic effect of La-doping and GO capsulation to mitigate Jahn-Teller distortion. In addition, the selective adsorption–desorption mechanism of Li+ was confirmed. This work introduces a facile approach for the fabrication of robust carbon-based LMO hybrids, demonstrating the potential applications as high-performance lithium-selective materials.

Understanding the Electrochemical Extraction of Lithium from Ultradilute Solutions.

The electrochemical extraction of lithium (Li) from aqueous sources using electrochemical means is a promising direct Li extraction technology. However, to this date, most electrochemical Li extraction studies are confined to Li-rich brine, neglecting the practical and existing Li-lean resources, with their overall extraction behaviors currently not fully understood. More still, the effect of elevated sodium (Na) concentrations typically found in most Li-lean water sources on Li extraction is unclear. Hence, in this work, we first understand the electrochemical Li extraction behaviors from ultradilute solutions using spinel lithium manganese oxide as the model electrode. We discovered that Li extraction depends highly on the Li concentration and cell operation current density. Then, we switched our focus on low Li to Na ratio solutions, revealing that Na can dominate the electrostatic screening layer, reducing Li ion concentration. Based on these understandings, we rationally employed pulsed electrochemical operation to restructure the electrode surface and distribute the surface-adsorbed species, which efficiently achieves a high Li selectivity even in extremely low initial Li/Na concentrations of up to 1:20,000.

Reduced Lattice Constant in Al-Doped LiMn2O4 Nanoparticles for Boosted Electrochemical Lithium Extraction.

Extracting lithium selectively and efficiently from brine sources is crucial for addressing energy and environmental challenges. The electrochemical system employing LiMn2O4 (LMO) electrodes has been recognized as an effective method for lithium recovery. However, the lithium selectivity and stability of LMO need further enhancement for its practical applications. Herein, the Al-doped LMO with reduced lattice constant is successfully fabricated through a facile one-step solid-state sintering method, leading to enhanced lithium selectivity. The reduced lattice constant in Al-doped LMO is proved through spectroscopic analyses and theoretic calculations. Compared to the original LMO, the Al-doped LMO (LiAl0.05Mn1.95O4, LMO-Al0.05) exhibits highercapacitance, lower resistance, and improved stability. Moreover, the LMO-Al0.05 with reduced lattice constant can offer higher Li+ diffusion coefficient and lower intercalation energy revealed by cyclic voltammetry and multiscale simulations. When employed in hybrid capacitive deionization (CDI), the LMO-Al0.05 obtains a Li+ intercalation capacity of 21.7mgg-1 and low energy consumption of 2.6Whmol-1 Li+. Importantly, the LMO-Al0.05 achieves a high Li+ extraction percentage (≈86%) with Li+/Na+ and Li+/Mg2+ selectivity of 1653.8 and 434.9, respectively, in synthetic brine. The results demonstrate that the Al-doped LMO with reduced lattice constant could be a sustainable solution for electrochemical lithium extraction.

Electrochemical lithium extraction with continuous flow electrodes

Electrochemical lithium extraction presents the advantages of superior ion selectivity and environmental friendliness. However, it faces challenges of intermittent operation, limited areal capacity and constrained mass transfer with conventional solid electrodes. In this work, we propose a continuous electrochemical lithium extraction system by using flow electrodes. Due to the inherent fluidic characteristics, the flow electrodes facilitate efficient mass transfer, thereby manifesting boosted kinetics in the insertion and extraction of lithium ions. Compared with solid electrodes, flow electrodes exhibit a substantial augmentation in lithium extraction capacity, demonstrating a nearly sixfold increase in simulated Atacama brine and a nineteen-fold in diluted Atacama saline under equivalent current density. Furthermore, we achieve a lithium production rate of 1 mol m−2 h−1 with a purity level of 0.97 at a high current density of 4 mA cm−2. These results exemplify the capability of flow electrodes for industrial-scale lithium extraction, particularly emphasizing their suitability for large-scale and high-speed production.

Electrochemical selective lithium extraction and regeneration of spent lithium iron phosphate

In this paper, a green, efficient and low-cost process for the selective recovery of lithium from spent LiFePO4 by anodic electrolysis is proposed. The leaching rates of Li, Fe and P under different conditions were explored and the optimal conditions are obtained. In the optimal conditions, Li, Fe and P leaching rates were 96.31%, 0.06% and 0.62% respectively. The Li/Fe selectivity was over 99.9%. The product obtained is isostructural FePO4 and retains the original particle morphology. The FePO4 obtained can be synthesised into LiFePO4/C by direct regeneration process or impurity removal regeneration process. The material synthesized by the latter process has a better electrochemical performance, with a discharge specific capacity of 144.5 mAh/g at 1.0C and a capacity retention of 92.0% over 500cycles. The superior performance can be attributed to an impurity removal process that reduced agglomeration and improved particle morphology.

Ionic transport kinetics of selective electrochemical lithium extraction from brines

Lithium extraction from brines by electrochemical De-intercalation/Intercalation method with LiFePO4 as host materials has attracted extensive attention, but the ionic transport properties and rate-determining step of this process are not fully understood. Therefore, to address this knowledge gap, we study the electrode process kinetics of LiFePO4/Li1-xFePO4 (0 <x < 1) in brines by electrochemical impedance spectroscopy. The results reveal that the diffusion of Li+ in electrode is the rate-determining step, the apparent diffusion coefficient DLi shows a trend of first increasing and then decreasing with the increase of electrode coating density, and the maximum value is obtained as 2.23 × 10−11 cm−2·s−1 at 55 mg·cm−2. The charge transfer resistance Rct and Warburg impedance Zω decrease with increasing temperature and do not change significantly with Li+ concentration, but Mg2+ has an inhibitory effect on Li+ charge exchange. Furthermore, the Li+ charge transfer at electrode/solution interface is differentiated for different de-lithiated Li1-xFePO4 electrodes, the Rct reaches a minimum around Li0.3FePO4. The diffusion of other competing cations is more difficult than Li+ in electrodes, which gives theoretical support for selective lithium extraction from brines from a kinetic point of view.