Search Results (163)

MXenes, a rapidly emerging family of two-dimensional transition metal carbides and nitrides, have attracted considerable attention in recent years for their potential in next-generation energy storage technologies. In solid-state batteries (SSBs), they combine metallic-level conductivity (>10³ S cm⁻¹), adjustable surface terminations, and mechanical resilience, which makes them suitable for diverse functions within the cell architecture. Current studies have shown that MXene-based anodes can deliver reversible lithium storage with Coulombic efficiencies approaching ~98% over 500 cycles, while their use as conductive additives in cathodes significantly improves electron transport and rate capability. As interfacial layers or structural scaffolds, MXenes effectively buffer volume fluctuations and suppress lithium dendrite growth, contributing to extended cycle life. In solid polymer and composite electrolytes, MXene fillers have been reported to increase Li⁺ conductivity to the 10⁻³–10⁻² S cm⁻¹ range and enhance Li⁺ transference numbers (up to ~0.76), thereby improving both ionic transport and mechanical stability. Beyond established Ti-based systems, double transition metal MXenes (e.g., Mo₂TiC₂, Mo₂Ti₂C₃) and hybrid heterostructures offer expanded opportunities for tailoring interfacial chemistry and optimizing energy density. Despite these advances, large-scale deployment remains constrained by high synthesis costs (often exceeding USD 200–400 kg⁻¹ for Ti₃C₂T_x at lab scale), restacking effects, and stability concerns, highlighting the need for greener etching processes, robust quality control, and integration with existing gigafactory production lines. Addressing these challenges will be crucial for enabling MXene-based SSBs to transition from laboratory prototypes to commercially viable, safe, and high-performance energy storage systems. Beyond summarizing performance, this review elucidates the mechanistic roles of MXenes in SSBs—linking lithiophilicity, field homogenization, and interphase formation to dendrite suppression at Li|SSE interfaces, and termination-assisted salt dissociation, segmental-motion facilitation, and MWS polarization to enhanced electrolyte conductivity—thereby providing a clear design rationale for practical implementation. Full article

The widespread implementation of next-generation Li metal anodes is limited, in part, due to the formation of dendritic and/or mossy electrodeposits during cycling. These morphologies can lead to battery failure due to the formation of short circuits and significant volumetric expansion at the anode. One strategy to control the electrodeposition of Li metal is to use lithiophilic materials at the anode. Here, we evaluate the impact of Ag and Au on the early stages of Li metal electrodeposition and cycling. The alloying substrates decrease the voltage for Li reduction and improve Li wetting/adhesion. We probe volumetric expansion directly through dilatometry measurements and find that the degree of volumetric expansion is less when lithium is cycled on an alloying substrate compared to a non-alloying substrate (Cu). Dilatometry experiments reveal that Au has the least amount of volumetric expansion and coin cell cycling experiments indicate that Ag yields more stable cycling compared to Au or Cu. The evaluation of in situ cross-sectional images of cycled coin cells shows that Ag has the lowest volumetric expansion in a coin cell format. Full article

Accurate imaging methods are important for understanding electrodeposition phenomena in metal batteries. Among the suitable imaging methods for this task is magnetic resonance imaging (MRI), which is a very powerful radiological diagnostic method. In this study, MR microscopy was used to image electroplating in a lithium symmetric cell, which was used as a model for a lithium-metal battery. Lithium electrodeposition in this cell was studied by sequential 3D ¹H MRI of 1 M LiPF₆ in EC/DMC electrolyte under different charging conditions, which resulted in different dynamics of the amount of electroplated lithium and its structure. The acquired images depicted the electrolyte distribution, so that the images of deposited lithium that did not give a detectable signal corresponded to the negatives of these images. With this indirect MRI, phenomena such as the transition from a mossy to a dendritic structure at Sand’s time, the growth of whiskers, the growth of dendrites with arborescent structure, the formation of dead lithium, and the formation of gas due to electrolyte decomposition were observed. In addition, the effect of charge and discharge cycles on electrodeposition was also studied. It was found that it is difficult to correctly predict the occurrence of these phenomena based on charging conditions alone, as seemingly identical conditions resulted in different results. Full article

Recent advancements in lithium-metal-based battery technology have garnered significant attention, driven by the increasing demand for high-energy storage devices such as electric vehicles (EVs). Lithium (Li) metal has long been considered an ideal negative electrode due to its high theoretical specific capacity (3860 mAh g⁻¹) and low redox potential. However, the commercialization of Li-metal batteries (LMBs) faces significant challenges, primarily related to the safety and cyclability of the negative electrodes. The formation of lithium dendrites and uneven solid electrolyte interphases, along with volumetric expansion during cycling, severely hinder the commercial viability of LMBs. Among the various strategies developed to overcome these challenges, the introduction of artificial protective layers and the structural engineering of current collectors have emerged as highly promising approaches. These techniques are critical for regulating Li deposition behavior, mitigating dendrite growth, and enhancing interfacial and mechanical stability. This review summarizes the current state of Li-negative electrodes and introduces methods of enhancing their performance using a protective layer and current collector design. Full article

Lithium–sulfur batteries (LSBs) are favorable candidates for advanced energy storage, boasting a remarkable theoretical energy density of 2600 Wh kg⁻¹. Moreover, several challenges hinder their practical implementation, including sulfur’s intrinsic electrical insulation, the shuttle effect of lithium polysulfides (LiPSs), sluggish redox kinetics of Li₂S₂/Li₂S, and the uncontrolled growth of Li dendrites. These issues pose significant obstacles to the commercialization of LSBs. A viable strategy to address these challenges involves using MXene materials, 2D transition metal carbides, and nitrides (TMCs/TMNs) as hosts, functional separators, or interlayers. MXenes offer exceptional electronic conductivity, adjustable structural properties, and abundant polar functional groups, enabling strong interactions with both S cathodes and Li anodes. Despite their advantages, current MXene synthesis methods predominantly rely on acid etching, which is associated with environmental concerns, low production efficiency, and limited structural versatility, restricting their potential in LSBs. This review provides a comprehensive overview of traditional and environmentally sustainable MXene synthesis techniques, emphasizing their applications in developing S cathodes, Li anodes, and functional separators for LSBs. Additionally, it discusses the challenges and outlines future directions for advancing MXene-based solutions in LSBs technology. Full article

Metallic lithium anodes possess the lowest redox potential (−3.04 V vs. SHE) and an ultra-high theoretical capacity (3860 mAh g⁻¹, 2061 mAh cm⁻³). However, during electrochemical cycling, lithium metal tends to plate unevenly, leading to the formation of lithium dendrites. Moreover, severe electrochemical corrosion occurs at the interface between metallic lithium and traditional copper foil current collectors. To address these issues, we selected corrosion-resistant carbon paper as a lithium metal host and modified a uniform distribution of silver nanoparticles and a F-doped amorphous carbon structure as a highly lithiophilic F-CP@Ag host to enhance lithium-ion transport kinetics and achieve improved affinity with lithium metal. The silver nanoparticles reduced the lithium nucleation energy barrier, while F doping resulted in a LiF-rich solid electrolyte interphase that better accommodated volume changes in lithium metal. These two strategies worked together to ensure uniform and stable lithium metal plating/stripping on the F-CP@Ag host. Consequently, under the conditions of 1 mA cm⁻² and 1 mAh cm⁻², the symmetric cell exhibited stable cycling with a polarization voltage of 8 mV for up to 1400 h. This work highlights the corrosion problem of lithium metal on traditional copper foil current collectors and provides guidance for the long-term cycling stability of lithium metal anodes. Full article

The poor thermal stability of polypropylene (PP) separators poses risks of electrolyte leakage and battery short-circuiting, limiting their application in lithium metal batteries (LMBs). To address these challenges, a gel polymer membrane was designed using polymer blending technology. This membrane effectively retains the electrolyte, provides a stable environment, enhances thermal stability, and significantly decreases the risk of battery explosions and side reactions between the lithium metal and the electrolyte. Compared to commercial PP separators, the developed blend-type gel polymer electrolyte (b-GPE) demonstrates a superior performance, including structural stability at temperatures up to 150 °C and a high lithium-ion transference number ($t_{{Li}^{+}}$) of 0.513. Furthermore, a cell with a LiCoO₂ cathode operated at a 1 C rate retains 97.4% of its capacity after 300 cycles. After exposure to 120 °C, the b-GPE-120 demonstrates that its performance is comparable to that of the b-GPE, such as a $t_{{Li}^{+}}$ of 0.506, a high electrolyte absorption rate, and a wide electrochemical window of 5.2 V. Full article

Uneven local electric fields and limited nucleation sites at the reaction interface can lead to the formation of hazardous lithium (Li) dendrites, posing a significant safety risk and impeding the practical utilization of Li metal anodes (LMAs). Here, we present a method utilizing atomic layer deposition (ALD) to create lithiophilic titanium nitride (TiN) sites on carbon nanotubes (CNTs) surfaces, integrated with nanocellulose to form a lithiophilic interlayer (NFCP@TN). This interlayer, which is highly flexible and electrolyte-wettable, functions as a current collector and host material for LMAs. The uniform deposition of Li is facilitated by the synergistic interplay of the lithiophilic active sites TiN, the conductive CNT network, and excellent electrolyte wettability of nanocellulose. As a result, Li preferentially adsorbs on TiN sheaths with lower diffusion barriers, leading to controlled nucleation sites and dendrite-free Li deposition. Furthermore, the well-designed NFCP@TN interlayer exhibits exceptional electrochemical performance and significantly extended cycle life when paired LMA with high areal capacity NCM811 (5.0 mAh cm⁻²) electrodes. Full article

Polyphenylene sulfide (PPS)-based separators have garnered significant attention as high-performance components for next-generation lithium-ion batteries (LIBs), driven by their exceptional thermal stability (>260 °C), chemical inertness, and mechanical durability. This review comprehensively examines advances in PPS separator design, focusing on two structurally distinct categories: porous separators engineered via wet-chemical methods (e.g., melt-blown spinning, electrospinning, thermally induced phase separation) and nonporous solid-state separators fabricated through solvent-free dry-film processes. Porous variants, typified by submicron pore architectures (<1 μm), enable electrolyte-mediated ion transport with ionic conductivities up to >1 mS·cm⁻¹ at >55% porosity, while their nonporous counterparts leverage crystalline sulfur-atom alignment and trace electrolyte infiltration to establish solid–liquid biphasic conduction pathways, achieving ion transference numbers >0.8 and homogenized lithium flux. Dry-processed solid-state PPS separators demonstrate unparalleled thermal dimensional stability (<2% shrinkage at 280 °C) and mitigate dendrite propagation through uniform electric field distribution, as evidenced by COMSOL simulations showing stable Li deposition under Cu particle contamination. Despite these advancements, challenges persist in reconciling thickness constraints (<25 μm) with mechanical robustness, scaling solvent-free manufacturing, and reducing costs. Innovations in ultra-thin formats (<20 μm) with self-healing polymer networks, coupled with compatibility extensions to sodium/zinc-ion systems, are identified as critical pathways for advancing PPS separators. By addressing these challenges, PPS-based architectures hold transformative potential for enabling high-energy-density (>500 Wh·kg⁻¹), intrinsically safe energy storage systems, particularly in applications demanding extreme operational reliability such as electric vehicles and grid-scale storage. Full article

Lithium (Li) metal’s exceptional low electrode potential and high specific capacity for next-gen energy storage devices make it a top contender. However, the unregulated and unpredictable proliferation of Li dendrites and the instability of interfaces during repeated Li plating and stripping cycles pose significant challenges to the widespread commercialization of Li metal anodes. We introduce the creation of a hydrogen bond network solid electrolyte interphase (SEI) film that integrates zwitterionic groups, designed to facilitate the stability and longevity of lithium metal batteries (LMBs). Here, we design a PVA/P(SBMA-MBA) hydrogen bond network film (PSM) as an artificial SEI, integrating zwitterions and polyvinyl alcohol (PVA) to synergistically regulate Li⁺ flux. The distinctive zwitterionic effect in the network amplifies the SEI film’s ionic conductivity to 1.14 × 10⁻⁴ S cm⁻¹ and attains an impressive Li⁺ ion transfer number of 0.84. In situ Raman spectroscopy reveals dynamic hydrogen bond reconfiguration under strain, endowing the SEI with self-adaptive mechanical robustness. These properties facilitate a homogeneous Li flux and exceptionally suppress dendritic growth. The advanced Li metal anode may endure over 1200 h at 1 mA cm⁻² current density and 1 mAh cm⁻² area capacity in a Li|Li symmetric battery. And in full cells paired with LiFePO₄ cathodes, 93.8% capacity retention is reached after 300 cycles at 1C. Consequently, this work provides a universal strategy for designing dynamic interphases through molecular dipole engineering, paving the way for safe and durable lithium metal batteries. Full article

Interfacial modification strategies for lithium metal anodes have emerged as a promising method to improve cycling stability, suppress lithium dendrite growth, and increase Coulombic efficiency. However, the reported chemical synthesis methods lead to side reactions and side products, which hinder their electrochemical performance. In this study, we propose a novel and facile red phosphorus-assisted solid-state friction method to in situ fabricate a uniform Li₃P interphase directly on the surface of lithium metal. Interestingly, the as-formed artificial Li₃P interphase with high ionic conductivity and lithium affinity features significantly enhanced interfacial stability and electrochemical kinetics. The symmetric cells based on Li@P with the Li₃P interphase achieved a prolonged lifespan, over 1000 h, at 1 mA/cm² with low polarization. When paired with a high-loading LiFePO₄ cathode (10.5 mg/cm²), the Li@P||LiFePO₄ full cell retained 88.9% of its capacity after stable cycling for 550 cycles at 2 C and further demonstrated the excellent performance and stability of the Li@P‖LiCoO₂ full pouch cell. This study provides an efficient and scalable strategy for stabilizing lithium metal anodes, expanding new ideas for the development of next-generation high-energy-density batteries. Full article

The increasing demand for sustainable and cost-effective battery technologies in electric vehicles (EVs) has driven research into alternatives to lithium-ion (Li-ion) batteries. This study investigates magnesium-ion (Mg-ion) batteries as a potential solution, focusing on their energy density, cycle stability, safety, and scalability. The research employs a comprehensive methodology, combining electrochemical testing and simulation models, to analyse magnesium-based anodes, sulphur-based cathodes, and advanced electrolytes such as HMDS₂Mg. Key findings reveal that Mg-ion batteries achieve a practical energy density of 500–1000 mAh/g, comparable to high-performance Li-ion systems. With sulphur–graphene cathodes, Mg-ion batteries demonstrated 92% capacity retention after 500 cycles, a 10% improvement over standard configurations. Ionic conductivity reached 1.2 × 10⁻² S/cm using HMDS₂Mg electrolytes, significantly reducing passivation layer growth to 5 nm after 100 cycles, outperforming Grignard-based systems by 30%. However, the research identified a 15% reduction in charge–discharge efficiency compared to Li-ion batteries due to slower ion diffusion kinetics. This study highlights the safety advantage of magnesium-ion batteries, which eliminate dendrite formation and reduce thermal runaway risks by 40%. These findings position Mg-ion batteries as a promising, sustainable alternative for EVs, emphasising the need for further optimisation in scalability and efficiency. Full article

In this work, hollow dodecahedral carbon structures with abundant N-doping sites and metal nanoparticles (NC-Co-CNTs) based on MOF-derivative materials were designed and prepared as host materials for lithium metal to ensure uniform lithium deposition on a Cu current collector. NC-Co-CNTs have good electrical conductivity, which ensures fast electron transport and Li⁺ transfer. The carbon nanotubes catalytically derived by Co can promote the uniform distribution of Li⁺ along the hollow dodecahedral carbon surface and deposition inside the cavity, and the larger electronegativity of N-doped sites and lithophilic sites such as Co nanoparticles can effectively adsorb lithium, inducing the Li⁺ to be deposited in the form of spherical lithium in a dendrite-free state, inhibiting the growth of dendritic lithium and improving the electrochemical performance of the lithium metal battery. Based on the above advantages, the electrodes of NC-Co-CNT-based symmetric cells present superior cycling performance for more than 1100 h with low overpotential at 1 mAh cm⁻²/1 mAh·cm⁻². Even cycling at high current density of 5 mA cm⁻² and high deposition parameters of 5 mAh cm⁻², it still cycles for up to 800 h at a relatively low overpotential. Full article

A Si/SiC/SiO₂ (53/44/3 wt.%) composite is evaluated as an anode material for Li-ion batteries. This material, a result of the high-energy ball-milling of a by-product of the carbothermal reduction of silica (Si slag), is predominantly made up of micrometric particles of amorphous or short-range order Si in which submicrometric SiC inclusions are dispersed. Its capacity is 860 mAh g⁻¹ (1.7 mAh cm⁻²) after 200 cycles in half-cell configuration and 1.6 mAh cm⁻² after 70 cycles in full-cell. The SiC component is not electroactive for lithiation but plays a key role in the electrode stability by preventing the formation of the c-Li₁₅S_i4 phase, known to accelerate electrode degradation. It is shown that capacity decay with cycling mainly originates from solid electrolyte interphase (SEI) growth rather than particle disconnections. Complementary wide angle X-ray scattering (WAXS) analyses confirm the SEI grows alongside cycling and allows for the highlighting of its major components, namely, Li₂CO₃ and LiF. The morphological evolution of the electrode upon cycling is studied by electrochemical dilatometry, operando optical microscopy, and focused ion beam (FIB) and broad ion beam (BIB) scanning electron microscopy (SEM). No particle cracking is observed. However, reconstructed 3D imaging of the electrodes before and after 10 and 200 cycles clearly shows that the particles progressively evolve a dendritic structure. The SEI grows on and within the particles and induces a significant decrease in the electrode’s porosity and an increase in its thickness. Full article

The increasing demand for high-specific-energy lithium batteries has stimulated extensive research on the lithium metal anode owing to its high specific capacity and low electrode potential. However, the lithium metal will irreversibly react with the electrolyte during the first cycling process, forming an uneven and unstable solid electrolyte interphase (SEI) layer, which results in the non-uniform deposition of Li ions and thus the formation of lithium dendrites. This could cause a battery short circuit, resulting in safety hazards such as thermal runaway. In addition, the continuous rupture and repair of the SEIs during the repeated charge/discharge processes will constantly consume the active lithium, which leads to a significant decrease in battery capacity. An effective strategy to address these challenges is to design and construct ideal artificial SEIs on the surface of the lithium metal anode. This review analyzes and summarizes the mathematical modeling of SEI, the functional characteristics of SEIs with different components, and finally discusses the challenges faced by artificial SEIs in practical applications of lithium metal batteries and future development directions. Full article