Search Results (1,537)

Silicon/carbon (Si/C) composites combine the high theoretical specific capacity of silicon with the electronic conductivity, structural stability, and volume-buffering capability of carbon, making them promising anode candidates for next-generation high-energy-density lithium-ion batteries. However, the substantial volume variation of silicon during repeated charge/discharge processes continuously perturbs the electrode/electrolyte interface, and the resulting interfacial instability remains a major barrier to practical application. Porous carbon host design and Si/C interface regulation have become key routes for improving structural robustness and electrochemical performance. Most existing reviews focus on the failure mechanisms of silicon-based anodes or the structural classification of Si/C composites, whereas the structural regulation role of porous carbon hosts has not been systematically summarized. This review places porous carbon hosts at the center of analysis and summarizes the main preparation strategies, including the hard-templating method, soft-templating method, combined hard- and soft-templating method, template-free synthesis, and etching strategies, with emphasis on their pore-forming mechanisms, structural regulation features, and industrialization potential. Building on this host-centered framework, silicon incorporation and carbon coating strategies are further discussed in terms of their effects on silicon distribution, Si/C interfacial stability, electronic transport, and volume-expansion accommodation. This review further evaluates recent advances in Si/C anodes for lithium-ion batteries from the perspectives of initial Coulombic efficiency, cycling stability, and practical electrode performance. Finally, key challenges related to scalable preparation, structural consistency, electrode-processing compatibility, and industrial adaptation are identified, and future directions for porous-carbon-host-based Si/C anodes are proposed. Full article

The rapid growth of electric mobility, renewable-energy storage, and portable electronics has sharply increased global lithium demand. Conventional lithium extraction methods, including hard-rock mining and brine evaporation, are land-intensive, slow, water-consumptive, and carbon-intensive. Adsorption has therefore received substantial attention for lithium recovery, due to its simple operation, cost-effectiveness, and facile scalability. In this regard, zeolite-based adsorbents have emerged as promising next-generation materials, mainly because of their crystalline frameworks, tunable pore architectures, ion-exchange functionality, and exceptional thermal and chemical stability. Existing reviews on adsorption-based lithium recovery have predominantly focused on polymeric materials, ion-exchange resins, and lithium-ion sieves (including lithium manganese oxide-based, titanium-based, and aluminum hydroxide-based adsorbents). To fill this gap, we present a dedicated and comprehensive review of zeolite-based adsorbents for sustainable lithium recovery from non-conventional lithium resources such as brines, geothermal fluids, seawaters, and battery-recycling leachates. By systematically and rigorously analyzing existing studies on this topic, we identify five guiding design principles: (i) zeolite framework charge density, (ii) zeolite framework topology and pore architecture (iii) morphology (size and shape), (iv) zeolite-based hybrid materials, and (v) operational design parameters (e.g., pH and temperature). Each design element is discussed in depth to clarify how lithium adsorption capacity and selectivity, transport behavior, and adsorption mechanisms can be controlled across diverse feedstocks. We further discuss the advantages, limitations, and future research needs for zeolite-based lithium capture. To the best of our knowledge, this is the first review centered on zeolite-based materials for lithium recovery. The knowledge and insights provided here aim to drive researchers into advancing zeolite-based adsorbents toward sustainable, next-generation lithium recovery technologies. Full article

The development of carbon-based anode materials for high-performance lithium-ion batteries has been limited by their low theoretical capacity density, low conductivity, and high manufacturing costs. Herein, natural Si/N co-doped biomass carbon micron-tubes, derived from reed catkins, were synthesized. The as-prepared RC-Si/N anode exhibits a good discharge capacity of 761.3 mAh g⁻¹ at 100 mA g⁻¹ after 200 cycles. Moreover, it exhibits outstanding cycling stability, retaining discharge capacities of 517.7 mAh g⁻¹ at 1 A g⁻¹ after 1000 cycles. The excellent electrochemical performance is attributed to the trace Si originating from the biomass precursor, which provides high specific capacity, while N doping introduces structural defects and improves electronic conductivity. Coupled with its unique micrometer-scale tubular morphology, the material facilitates efficient lithium-ion transport and storage. Further DFT calculations corroborate enhanced Li⁺ adsorption ability, sustained structural integrity over prolonged cycling, and promoted reaction kinetics. These findings underscore the potential of natural Si/N co-doped biomass-derived carbon as an advanced lithium-ion battery anode material. Full article

The increasing demand for lithium-ion batteries has intensified the search for sustainable alternatives to conventional graphite anodes. In this work, cotton-derived carbon fibers were prepared from commercial medical-grade cotton wool using a two-step pyrolysis process and investigated as hard-carbon anode materials for lithium-ion batteries. The structural and morphological properties of the prepared material were analyzed using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, revealing a predominantly amorphous carbon structure with a retained fibrous morphology after pyrolysis. Electrochemical performance was evaluated in CR2032 half-cells by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge–discharge measurements. The prepared hard carbon exhibited characteristic lithium-storage behaviour with irreversible processes during the initial cycle followed by stable reversible cycling. The material delivered a reversible capacity of approximately 780–800 mAh g⁻¹ after 300 cycles at a current density of 100 mA g⁻¹, together with stable Coulombic efficiency and good rate capability. Post-mortem analysis confirmed that the electrode structure remained stable after repeated cycling. The obtained results demonstrate the potential of waste cotton as a renewable precursor for the preparation of high-performance hard-carbon materials and highlight the applicability of biomass-derived carbons for sustainable electrochemical energy-storage systems. Full article

Fast-charging graphite-based lithium-ion batteries (LIBs) are limited by sluggish Li⁺ desolvation, interfacial charge transfer, and solid-state diffusion in graphite (Gr). Herein, a salt-concentration-regulated lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in 1,3-dioxolane (DOL) and fluoroethylene carbonate (FEC) electrolyte is developed to construct an anion-involved solvation structure for fast-charging graphite-based LIBs. At an appropriate LiTFSI concentration, TFSI⁻ is incorporated into the primary Li⁺ solvation sheath, forming a contact-ion-pair (CIP)-dominated solvation structure. The optimized electrolyte exhibits a Li⁺ transference number of 0.76 and an exchange current density of 0.28 mA cm⁻², indicating accelerated Li⁺ transport and interfacial charge transfer. Furthermore, a more uniform interfacial Li⁺ flux distribution is obtained, contributing to suppressed localized Li growth. As a result, Gr||Li half cells deliver 168 mAh g⁻¹ at 10 C (1 C = 370 mAh g⁻¹). LFP||Gr full cells with an LiFePO₄ (LFP) areal capacity of 4 mAh cm⁻² deliver 115 mAh g⁻¹ at 2 C and retain 69% capacity after 200 cycles. This work highlights moderate salt-concentration regulation in DOL/FEC electrolytes as an effective strategy for fast graphite lithiation without relying on fluorinated ether solvents or localized high-concentration formulations. Full article

Silicon suboxide (SiO_x) has been extensively investigated as an anode material for lithium-ion batteries. However, its low electrical conductivity and significant volume expansion during cycling have hindered its practical application. Although compounding SiO_x with carbon can effectively alleviate these issues, practical challenges such as complex preparation processes and high production costs still remain. In this study, porous SiO_x/C anode materials were synthesized in a single step using residue after acid-extraction aluminum from coal fly ash (high silica slag) as the silicon source and calcium carbide as both the reducing agent and carbon source, in a NaCl-CaCl₂ molten salt medium. The intimate interface between SiO_x and carbon not only enhances the electrical conductivity of the electrode but also buffers volume expansion, while the porous structure inside the SiO_x/C particles facilitates rapid ion transport. The SiO_x/C anode fabricated from this material exhibits excellent electrochemical performance and cycling stability: the anode material synthesized at 700 °C for 3 h (denoted as SiO_x/C-700-3) retains a reversible specific capacity of 1093.58 mAh g⁻¹ after 1000 cycles at a current density of 0.4 A g⁻¹. Moreover, the optimized SiO_x/C-700-3 electrode achieves robust long-cycle stability under a high current density of 2 A g⁻¹, sustaining a reversible capacity of 486.22 mAh g⁻¹ after 800 cycles with an average Coulombic efficiency approaching 99.6%. The method proposed in this work provides a new strategy for the preparation of SiO_x/C anode materials and holds great significance for the high-value comprehensive utilization of coal fly ash and the protection of the ecological environment. Full article

Given the confining effect of porous carbon and strong surface polarity of transition metal phosphides, their composite would be a promising cathode candidate to solve the problems of lithium–sulfur batteries including volume expansion and the shuttling effect of polysulfides. Herein, cobalt phosphide (CoP)-loaded phosphorous (P)-containing carbonized bamboo (CoP/PCBs) composites were fabricated via the co-pyrolysis of phytic acid, waste bamboo and Co(NO₃)₂·6H₂O via Joule heating at 600–1200 °C. Hydrogen radicals released from phytic acid enabled CoP/PCBs with developed porosity (438.1–812.4 m²/g). CoP nanoparticles coated with graphitic carbon were distributed uniformly on a porous matrix of PCBs. CoP/PCBs presented obviously enhanced adsorption capabilities for Li₂S₆, and 57.8–80.4 wt.% of sulfur was confined in CoP/PCBs/S cathodes. CoP/PCB heated at 1200 °C exhibited a high reversible capacity of 477.5 mAh/g after 500 cycles at a current density of 1 C with an average capacity decay rate of 0.045%. The specific capacity remained at 453.3 mAh/g after 300 cycles even under a high sulfur load of 4.0 mg/cm². Conversion of sulfur/polysulfides during the electrochemical process could be promoted via the physical confinement of sulfur and chemical confinement of Li₂S₆. This work provided a valuable reference for the facile fabrication of lithium–sulfur cathodes and utilization of metal phosphides in advanced lithium–sulfur battery systems. Full article

Lithium metal batteries are considered one of the most promising technological routes for next-generation energy storage systems with high energy density. However, when paired with high-voltage cathodes such as NCM811, conventional lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)-based electrolytes face severe corrosion of the aluminum current collector when the operating voltage exceeds 3.8 V vs. Li⁺/Li, leading to rapid capacity decay and even cell failure. In this work, we designed and synthesized a cyano-containing lithium salt, lithium cyano(trifluoromethanesulfonyl)imide (LiCTFSI), to address this issue. The electrochemical performance of 1 M LiCTFSI and 1 M LiTFSI in the same carbonate solvent was systematically compared in NCM811/Li cells. The results demonstrate that LiCTFSI effectively suppresses aluminum corrosion at high potentials and forms a thinner and more compact cathode electrolyte interphase to protect NCM811 cathodes. With the LiCTFSI electrolyte, NCM811/Li cells (mass loading = 19.55 mg cm⁻²) achieve a capacity retention of 81.7% after 200 cycles at a high cutoff voltage of 4.6 V vs. Li⁺/Li. This work provides a new strategy for developing advanced electrolyte salts for high-voltage, high-energy-density lithium metal batteries. Full article

Silicon anodes hold great promise in high-energy lithium-ion batteries (LIBs) owing to their ultrahigh theoretical specific capacity, appropriate operating voltage, and low costs. However, the drastic volume expansion, inferior electronic conductivity, and unstable solid electrolyte interphase of Si anodes severely restrict their practical application. Herein, a nest-shaped microporous silicon (NMPSi) is rationally designed via acid–base co-etching and then synergistically regulated by surface thin-film carbon coating and ZIF-67-derived hard carbon nanotemplate (NMPSi@THC) by an in situ liquid-phase coating strategy. The constructed unique architecture is capable of buffering the huge volume expansion of inner NMPSi during cycling and constructing an optimized electron/ion transport network, thereby stabilizing the SEI film and preserving the electrode’s structural integrity. When it is evaluated as a LIB anode, the NMPSi@THC exhibits typically improved initial coulombic efficiency (ICE) and outstanding long-life cyclic stability (622.7 mAh g⁻¹ after 300 cycles at 1 A g⁻¹ and 2 mg cm⁻²). Furthermore, the NMPSi@THC//LiFePO₄ full cell delivers an ultrahigh ICE of 94% and a capacity retention rate of 86%, demonstrating its practical application potential. Compared with most recently reported Si anodes, this report delivers better cycling stability and maintains more intact electrode structure under relatively high current density and areal mass loading in half/full cells after long-term cycling. This research offers a convenient and scalable route to fabricate highly stable microporous Si anodes toward high-energy and long-lifespan LIBs. Full article

Maintaining a conductive network is essential for achieving high energy density and long-term reliability in lithium-ion batteries. However, its stability is often compromised by structural non-uniformity, and under high-voltage operation, by the oxidative degradation of carbon-based conductive additives. To address these issues, we propose a composite cathode design that combines multi-component electrophoretic deposition (EPD) with a chemically stable Ti₄O₇ conductive oxide. The EPD conditions were systematically investigated, and an applied voltage of 100 V was identified as the standard voltage for controlling electrode loading while avoiding cracking and delamination under severe deposition conditions. The electrochemical performance of the EPD-derived electrodes depended strongly on the Ti₄O₇ content in the initial EPD suspension. Ti-0 and Ti-1, prepared from suspensions containing 0 and 1 wt% Ti₄O₇, respectively, maintained stable capacity delivery over a wide loading range, with areal capacities in good agreement with the theoretical values. In contrast, Ti-5, prepared from a suspension containing 5 wt% Ti₄O₇, exhibited significant capacity degradation and failed under high-loading conditions. High-voltage cycling over 50 cycles and impedance analysis further showed that Ti-1 exhibited better cycling behavior than Ti-0, with less pronounced resistance growth, whereas Ti-5 displayed poor cycling performance. These results suggest that multi-component EPD with an appropriate amount of Ti₄O₇ can provide a balanced hybrid conductive network for improving the relative high-voltage cycling behavior of cathodes within the tested condition. Full article

Lithium has become one of the key raw materials for the energy transition due to the central role of lithium-ion batteries in electromobility, energy storage, and the integration of renewable energy sources. However, the rapid increase in demand reveals growing environmental, social, geopolitical, and market tensions. The aim of the paper is a critical synthesis of global lithium utilization from the perspective of challenges, technological innovations, and integrative strategies supporting a more sustainable material-energy system. A broad, systematic literature review covering the entire value chain was applied: resources, extraction, processing, end-use applications, second life of batteries, recycling, and governance. The analysis shows that the strategic importance of lithium arises from the increasing demand pressure from electric vehicles and stationary storage, while the sustainability of the current model is constrained by supply concentration, uneven control over downstream stages, the water-carbon footprint of extraction and processing, social conflicts, and incomplete integration of secondary loops. At the same time, innovations such as direct lithium extraction (DLE), recovery from geothermal brines, design for recycling, second life, and battery passports can partially alleviate these tensions, but they do not eliminate the need for primary supply in the short term. The conclusion of the work is that sustainable global lithium utilization requires simultaneous diversification of sources, development of circular value chains, and multi-level governance integrating resource security, environmental efficiency, and social legitimacy. Full article

Silicon (Si) is a leading anode candidate for next-generation lithium-ion batteries owing to its high theoretical capacity (~4200 mAh/g), but its >300% volumetric expansion during lithiation causes particle pulverization, loss of electrical contact, and continuous solid electrolyte interphase (SEI) reformation, resulting in rapid capacity fade. Here, we report a single-walled carbon nanotube (SWNT)-templated porous Si/SiO₂ core–shell cylindrical hybrid anode synthesized by combining block copolymer-directed sol–gel assembly with controlled magnesiothermic reduction. SWNT bundles act as a three-dimensional structural template that directs the formation of a continuously interconnected cylindrical porous network, a geometry difficult to obtain by conventional particle-based compositing. The controlled, partial magnesiothermic reduction intentionally preserves residual amorphous SiO₂ within the porous shell as an electrochemically inactive mechanical buffer that suppresses Si volume expansion and stabilizes the electrode. A side-by-side comparison with a fully reduced, SiO₂-free counterpart of identical architecture isolates the role of the SiO₂ buffer in achieving long-term cycling stability. The SWNT-porous Si/SiO₂ hybrid delivers a reversible capacity of 1133 mAh/g in the first cycle and retains 90% of its initial capacity after 200 cycles at 1 C with 99.7% Coulombic efficiency, together with a rate capability of 482 mAh/g at 5 C. Post-cycling cross-sectional analysis confirms minimal electrode-level swelling (~2 μm) after 200 cycles, demonstrating the structural efficacy of the SWNT-templated porous architecture combined with the SiO₂ buffer for structurally stable Si anodes. Full article

Lithium is a key element in the transition to carbon-free power generation. Over the last decade or so, there has been a surge in extracting lithium from its diverse natural sources, driven by a growing gap between its demand and production. Traditionally, lithium is extracted from salar brines; however, as the demand for this commodity has increased, processing from pegmatites and other types of brines and lithium-bearing clays is becoming more important. This paper revisits current technologies available to produce battery-grade lithium carbonate from diverse sources. We particularly discuss clay processing and the environmental issues associated with processing lithium from its natural sources. Plant data is required to make accurate environmental assessments concerning the processing of clay minerals. Uncertainties on the actual amount of lithium reserves exist, and it is unknown if, with the current data available, it is possible to close the gap between demand and supply of lithium. Full article

This study investigated the production of spodumene concentrate and lithium carbonate from a low-grade pegmatite ore containing approximately 0.26 wt.% Li₂O. The ore consisted predominantly of a quartz–feldspar aluminosilicate matrix with dispersed spodumene mineralization, which complicates conventional processing approaches. Preliminary lithium concentration was performed by dense media separation (DMS) using an industrially applicable ferrosilicon-based suspension. The highest separation efficiency was achieved for the −4.0/+2.8 mm fraction, producing a DMS concentrate containing 5.77 wt.% Li₂O with 98% lithium recovery. The obtained spodumene concentrate was subjected to decrepitation at 1000–1100 °C to convert α-spodumene into the more reactive β-modification, followed by sulfation roasting with concentrated sulfuric acid at 250–270 °C. The productive leach solution obtained after water leaching contained up to 12.1 g/L Li₂O. After purification from iron-bearing impurities and precipitation with sodium carbonate, a lithium carbonate product containing at least 98.8 wt.% Li₂CO₃ was obtained. Approximately 53% of the lithium contained in the original ore was recovered into the DMS feed fraction, whereas the overall lithium recovery into lithium carbonate reached about 45% relative to the ore and approximately 70% relative to the concentrate. Full article

Biomass-derived carbons are promising sustainable anode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) because biomass is renewable, abundant, low-cost, and naturally diverse in composition and morphology. Lignocellulosic frameworks, intrinsic heteroatoms, and biomass-derived inorganic species can be converted through carbonization, activation, graphitization, and doping into carbon architectures with tunable porosity, carbon ordering, and surface chemistry. This review first summarizes the compositional and structural features of biomass precursors and explains how processing conditions convert them into carbon frameworks. Recent advances in biomass-derived carbon anodes are then discussed by comparing the distinct design requirements for LIBs and SIBs. For LIBs, accessible surface area, hierarchical porosity, heteroatom-derived active sites, and improved electronic conductivity are generally beneficial for enhancing Li⁺ storage and rate capability. In contrast, SIB hard carbons require controlled surface exposure, expanded turbostratic spacing, and closed or latent pores to improve Na⁺ storage reversibility and initial Coulombic efficiency. These comparisons emphasize that biomass-derived carbon anodes should be designed according to system-specific storage mechanisms rather than a universal carbon design strategy. Full article