Li Loading Research Articles

Li+ Ion-Dipole Interaction-Enabled a Dynamic Supramolecular Elastomer Interface Layer for Dendrite-Free Lithium Metal Anodes.

The unstable lithium (Li)/electrolyte interface, causing inferior cycling efficiency and unrestrained dendrite growth, has severely hampered the practical deployment of Li metal batteries (LMBs), particularly in carbonate electrolytes. Herein, we present a robust approach capitalizing on a dynamic supramolecular elastomer (DSE) interface layer, which is capable of being reduced with Li metal to spontaneously form strong Li+ ion-dipole interaction, thereby enhancing interfacial stability in carbonate electrolytes. The soft phase in the DSE structure enables fast Li+ transport via loosely coordinated Li+-O interaction, while the hard phase, rich in electronegative lithiophilic sites, drives the generation of fast-ion-conducting solid electrolyte interface components, including Li3N and Li2S. Furthermore, the dynamically resilient DSE network composed of soft and hard phases protects Li anodes from electrolyte corrosion and accommodates volume changes during cycling. All features of the DSE layer synergistically facilitate uniform Li+ deposition and suppress Li dendrite propagation, ensuring a stable and dendrite-free Li anode. Consequently, the symmetric Li||Li cell incorporating the DSE layer achieves cycling stability exceeding 6000 h under 1 mA cm-2 and 1 mA h cm-2 conditions. Furthermore, full cell pairing DSE/Li anode with LiFePO4 (LFP) or high-voltage LiNi0.8Mn0.1Co0.1O2 (NMC811) cathodes exhibits high-efficiency Li deposition and cycling stability, even under constrained conditions of limited Li (40 μm) and ultrahigh loading NMC811 cathode (21.5 mg cm-2). This study underscores the effectiveness of the ion-dipole interaction-enabled DSE network in developing stable, high-energy-density LMBs.

Electronic State‐Modulated Ni4N/Zn3N2 Heterogeneous Nanosheet Arrays Toward Dendrite‐Free and Kinetic‐Enhanced Li‐S Full Batteries

AbstractThe applications of lithium (Li)–sulfur (S) batteries are simultaneously hampered by the unlimited dendritic Li growth and the sluggish redox kinetics of polysulfides (LiPSs). In this work, an electronic state‐modulated Ni4N/Zn3N2 heterogeneous nanosheet arrays is painstakingly fabricated on the surface of carbon cloth (CC@Ni4N/Zn3N2) as an efficient bi‐service host to promote uniform Li deposition and boost efficient LiPSs catalysis. It is found that the electronic structure of Ni4N/Zn3N2 heterostructure is modulated to realize a rational transition metal d‐band center, and its built‐in electric field (BIEF) within the heterointerfaces facilitates the interfacial charge transfer, resulting in low Li deposition/migration energy barrier and efficient LiPSs adsorption/catalytic conversion kinetics. As a result, the as‐prepared CC@Ni4N/Zn3N2‐Li anode can enable the Li||Li symmetrical cells to possess a long‐term lifespan over 500 h even at 10 mA cm−2/20 mAh cm−2, and the as‐assembled LiNi0.8Co0.1Mn0.1O2||CC@Ni4N/Zn3N2‐Li full cell also shows an excellent cycling performance (95.8% capacity retention after 100 cycles). When used for both S and Li loading, the as‐assembled CC@Ni4N/Zn3N2‐S||CC@Ni4N/Zn3N2‐Li full cell exhibits an outstanding cycling stability (744 mAh g−1 after 1000 cycles at 2C). This work highlights the great potential of heterostructures for fabricating ideal bi‐serve hosts for both Li and S electrodes.

Li-doped transition metal high-entropy oxides (Li/TM-HEOs) as Li-Ion batteries cathodes: a first report on capacity fading and cycling stability

High-Entropy Oxides (HEOs) have gained significant attention for their wide range of compositions and potential applications across various sectors, including rechargeable batteries. This study explores the characterization of two distinct HEO systems as potential cathode materials for Lithium-ion batteries (LIBs). A series of rock salt structured HEOs with varying Li loadings (16Li/RS-HEO, 25Li/RS-HEO, 33Li/RS-HEO, and 41Li/RS-HEO) and a spinel-structured HEO with 16 mol% of Li loading (16Li/SP-HEO) were firstly synthesized through co-precipitation. Electrochemical analyses via cyclic voltammetry revealed stark differences in the behavior of these structures. The Li/SP-HEO sample displayed broad and strongly irreversible hysteresis cycles, while the Li/RS-HEO series manifested thin, narrow hysteresis cycles with single oxidation peaks between 0.5 V and 0.7 V. As the lithium content increases in the RS-HEO system, the cycling stability of the cell decreases, most likely due to the reduced ratio of transition metal cations to lithium ions. Although there was a noticeable decrease in capacity under higher current rates, the higher lithium loadings positively impact the cell capacity, albeit with notable capacity fading under higher current rates. Li-doped rock salt structured high entropy materials show potential for LIB cathodes in terms of high specific capacities; the observed stability issues at medium and high current densities indicate a rapid electrode degradation.

Effects of the Hydroxy-Regulated Li-Montmorillonite Atomic Interface Arrangement on Li Cycle of Marine Sedimentation and pH.

The reaction of ubiquitous clay is related to the global cycle of the key metals, but the relationship between the Li occurrence interface and the sedimentation in the Li cycle remains unclear. We investigated the atomic interface arrangement of Li-montmorillonite (Li-Mt) during low-temperature water-rock reactions and Li migration. The results show that, in Cl-rich systems, deprotonation and exposure of Na adsorption sites cause Li enrichment and O pairing, which lead to the weakening of the shielding effect of Mt on anions and the formation of a Mt-Li-Cl atomically interfacial arrangement. Only up to 20.3% of the Li is contained in the atomic interface of Li-Mt. In F-rich system, the dehydroxylation of F paired with Al in octahedral sites causes Li accumulation via local crystallization of LiF, and co-complexation of F and Li forms a Mt(Al)-F-Li atomic interface, in which up to 46.8% of the Li is enriched by the Mt. The participation of F and Cl in the complexation intensifies lattice collapse of the Li-Mt edge. The sedimentation velocity decreases with the smaller particle size affected by the Li loading. Lithium leached from igneous rocks serves as the marine Li source, which contributes up to 99.8% and 99.5% of the Li in Cl- and F-rich systems, respectively. The response of Mt(OH) to Li migration with a time accumulating effect may make an important regulatory of oceanic pH by either acidification or alkalization.

Lithiophilic and Eco-Friendly Nano-Se Seeds Unlock Dendrite-Free and Anode-Free Li-Metal Batteries.

A 3D host design for lithium (Li)-metal anodes can effectively accommodate volume changes and suppress Li dendrite growth; nonetheless, its practical applicability in energy-dense Li-metal batteries (LMBs) is plagued by excessive Li loading. Herein, we introduced eco- and human-friendly Se seeds into 3D carbon cloth (CC) to create a robust host for efficient Li deposition/stripping. The highly lithiophilic nano-Se endowed the Se-decorated CC (Se@CC) with perfect Li wettability for instantaneous Li infusion. At an optimal Li loading of 17 mg, the electrode delivered an unprecedentedly long life span of 5400 h with low overpotentials <36 mV at 1 mA cm-2/1 mAh cm-2 and 1500 h at 5 mA cm-2/5 mAh cm-2. Furthermore, the uniform Se distribution and strong Li-Se binding allowed for further reduction in Li loading to 2 mg via direct Li electrodeposition. The corresponding LiNi0.8Co0.1Mn0.1O2 (NCM811)-based full cell afforded a high capacity retention rate of 74.67% over 300 cycles at a low N/P ratio of 8.64. Finally, the initial anode-free LMB using a NCM811 cathode and a Se@CC anode current collector demonstrated a high electrode-level specific energy of 531 Wh kg-1 and consistently high CEs >99.7% over 200 cycles. This work highlights a high-performance host design with excellent tunability for practical high-energy-density LMBs.

Constructing Ag@SiO2-TiO2 Nanofiber Interlayers with a Three-Dimensional Lithiophilic Gradient Framework for an Ultrastable Lithium Metal Anode.

Lithium metal batteries have become one of the most promising rechargeable batteries due to the ultrahigh theoretical specific capacity of the Li metal anode. However, the Li dendrite growth and volume change of the Li metal anode during repeated Li plating-stripping cycles restrict the practical viability. Herein, a unique lithiophilic gradient structure of uniformly incorporating Ag nanoparticles into a three-dimensional (3D) nanofiber framework with amorphous SiO2 and TiO2 hybrids was prepared by an electrospinning process and used as a multifunctional interlayer between the pristine separator and Li metal foil. The 3D framework not only possesses excellent flexibility but also alleviates volume changes, which can withstand massive Li loading and promote uniform Li+ distribution. In addition, the 3D lithiophilic gradient structure allows for regulable Li+ flux and suppresses Li dendrite growth. Impressively, the Li||Li symmetric batteries with Ag@SiO2-TiO2 interlayers exhibit a prolonged lifespan of 1500 h at 0.5 mA cm-2 for 0.5 mAh cm-2. The full cells coupled with the Ag@SiO2-TiO2 interlayer show a capacity retention rate of 94.6% after 1000 cycles and a high rate capability. This work provides promising guidance for the design of a gradient-distributed lithiophilic structure toward an ultrastable Li metal anode.

Limited Lithium Loading Promises Improved Lithium-Metal Anodes in Interface-Modified 3D Matrixes.

Confining Li metal in a three-dimensional (3D) matrix has been proven effective in improving the Li-metal anodes; however, in most studies, the loading of Li in the 3D matrix is far excessive, resulting in a dense bulk Li-metal anode with a low Li-utilization rate, forfeiting the effect of the 3D matrix. Here, we show that limiting the loading of Li metal within an interface-modified 3D carbon matrix not only increases the Li-utilization rate but also improves the electrochemical performance of the Li-metal anode. We use lithiophilic Fe2O3 granules anchored on a 3D carbon fiber scaffold to guide molten Li dispersion onto the fibers with controlled Li loading. Limiting Li loading maximizes the interface lithiophilic effect of the Fe2O3 granules while preserving sufficient space for electrolyte infusion, collectively ensuring uniform Li deposition and fast Li+ transport kinetics. The Li anode with limited Li dosage achieves remarkably improved Li-anode performances, including long lifespan, low voltage polarization, and low electrochemical resistance in both the symmetric cells and full cells. The improved electrochemical performance of the limited Li anode substantiates the importance to reduce Li loading from a fresh perspective and provides an avenue for building practical Li-metal batteries.

Preparation and properties of Mg-doped Li-B alloy anode materials for high specific-capacity thermal batteries

Thermal batteries with kilowatt power are crucial for improving the maneuverability of underwater weapons. Due to its high capacity, safety and stability, the new Li alloy anode has attracted extensive attention. In this study, Mg-doped Li-B alloy with high Li content was prepared by high temperature melting technology, and its Li loading was up to 64% and free Li content was more than 40%. The specific capacity of Mg-doped Li-B alloy was as high as 4270 As/g at the current density of 100 mA/cm2. Compared with the conventional Li-B alloy, the capacity of Mg-doped Li-B alloy is increased by 14.24%, and the specific energy can reach more than 140 Wh/kg. This work has guiding significance and great practical value for the research on high specific capacity anode for thermal battery.

High-temperature Fischer–Tropsch synthesis over the Li-promoted FeMnMgOx catalysts

Fischer–Tropsch-to-Olefins (FTO) over iron-based catalysts is a promising process for the production of light olefins from a non-petroleum source. However, the catalytic mechanism is unclear because of the variation in the iron phase during the reduction and activation processes and the complex iron phase composition under the reaction conditions. A series of Li-promoted FeMnMgOx catalysts is synthesized using co-precipitation and impregnation methods, after which the effect of promoters on the evolution of the iron phase, chemisorption, and FTO performance are analyzed. The results demonstrate that Mg enhances dissociative CO adsorption and hydrogen adsorption, improving the FTO activity. Mg facilitates the dispersion of α-Fe2O3 and suppresses the carbonization, which weakens the chain propagation, encourages the formation of short-chain hydrocarbons, and increases the selectivity of light olefins. Li also enhances dissociative CO adsorption and increases CO conversion. Moreover, Li facilitates the formation of the ε'-Fe2.2C phase, which reveals a higher FTS activity and better C–C coupling ability than the χ-Fe5C2 phase. This results in a decrease in CO2 and increase in light olefins. At the optimal Li loading, the FeMnMg-0.75Li sample displays the highest space time yield of light olefins at 355 g/(kgcat·h).

Gradient lithiation to load controllable, high utilization lithium in graphitic carbon host for high-energy batteries

The multiphase interaction between Li metal and carbon materials provides great opportunities to design advanced composite anodes for Li metal batteries. Herein, we report the conversion of single-sheet graphitic carbon papers (CPs) to function-gradient Li/C composite anodes with controllable formations of LiC6 and Li metal through controlling the thermal infiltration time. The uniform and dense lithiophilic LiC6 is formed first and gradually covers the entire CP host, which promotes the subsequent homogeneous infiltration of metallic Li into the CP. The resulting composite anode has a unique gradient structure, with one example consisting of a lithiated LiC6 coating of 5.8 mAh cm−2 and a thin Li bottom layer of 2.7 mAh cm−2. Such a gradient composite structure allows for the selective utilization of Li metal and LiC6 as the active component under different electrochemical conditions. This composite anode, with a much leaner Li loading than many reported Li/C composite anodes, has a stable porous framework and abundant lithiophilic sites, which enables uniform local electric field and stable Li metal deposition during cycling. Paired with high-capacity cathodes, the composite anode, with only a fraction of Li metal loading compared to Li foil, can provide better long-term cycling stability, and higher rate capability.

Conformal coating of lithium-zinc alloy on 3D conducting scaffold for high areal capacity dendrite-free lithium metal batteries

Li metal anode holds great promise to realize high-energy battery systems. However, the uncontrollable Li dendrites formation and infinite volume changes of Li severely hinder its practical applications. Herein, a 3D conductive carbon fibre with conformal lithiophilic Zn coating (CF@Zn) is developed to guide uniform Li plating/stripping and accommodate a large amount of Li metal. Phase evolution mechanism reveals that lithiated zinc (LiZn) alloy plays the real role in regulating the Li plating. Through the conformal incorporation of LiZn alloy, the Li affinity of carbon fibre has been improved significantly, which reduces the Li nucleation barrier and enables homogeneous Li nucleation and growth surround the carbon fibre, forming a conformal CF@LiZn@Li structure at initial stage. The 3D lithiophilic CF@LiZn scaffold with interconnected pores serves as robust host for high Li loading with small volume fluctuation, resulting in a dendrite-free Li metal battery with high areal capacity (up to 12 mAh cm−2). Moreover, the CF@LiZn electrode exhibits a high Coulombic efficiency of 97.1% at 5 mA cm−2, long cycle life of 280 cycles at 2 mA cm−2 and excellent rate performance (∼70 mV voltage hysteresis at 5 mA cm−2). Furthermore, excellent cyclability and rate performance are realized in full-cell batteries with CF@LiZn–Li anode and LiFePO4 cathode. This work demonstrates a low-cost and lithiophilic alloy matrix for the fabrication of stable Li metal anode toward next-generation high-energy battery systems.

Self-Propagating Enabling High Lithium Metal Utilization Ratio Composite Anodes for Lithium Metal Batteries.

Constructing three-dimensional (3D) structural composite lithium metal anode by molten-infusion strategy is an effective strategy to address the severe problems of Li dendritic growth and huge volume changes. However, various challenges, including uncontrollable Li loading, dense inner structure, and low Li utilization, still need to be addressed for the practical application of 3D Li anode. Herein, we propose a self-propagating method, which is realized by a synergistic effect of chemical reaction and capillarity effect on porous scaffold surface, for fabricating a flexible 3D composite Li metal anode with high Li utilization ratio and controllable low Li loading. The composite 3D anode possesses controllable low loading (8.0-24.0 mAh cm-2) and uniform grid structure, realizing a stable cycling over 600 h at a high Li metal utilization ratio over 75%. The proposed strategy for fabricating composite 3D anode could promote the practical application of Li metal batteries.

Lithiophilic diffusion barrier layer on stainless steel mesh for dendrite suppression and stable lithium metal anode

Lithium metal battery has high theoretical specific capacity but suffers from dendrite growth that leads to low Columbic Efficiency (CE) and uncontrolled volume expansion during cycling. Here, we develop a method for fabrication of a nitrogen-doped carbon-coating as a lithophilic diffusion barrier layer, by carbonizing polydopamine (PDA) on three-dimensional (3D) porous stainless steel (called Nitrogen-doped carbon stainless steel, N-C-SS) mesh, and used it as the current collector for Li metal anode. With this layer, we observed significant suppression of Li dendrite formation during Li deposition. More specifically, the N-C-SS/Li anode in symmetric cells exhibit stable cycling for over 1800 h, 4 times longer than the bare Li electrode. Similarly, the fabricated half cells retain an average CE of 98.1% after cycling 400 times and show a low overpotential of 12 mV, while for fabricated full cells, they retain 98.6% of their initial capacity 140 mA h g−1 after 200 cycles at 3C. Density functional theory (DFT) calculation results show that N-C-SS surface enables higher diffusion barrier, with more negative Li adsorption energy than the untreated SS surface or Cu or Li substrate, which guides Li nucleation and suppresses dendrite growth on the barrier layer. An additional advantage of SS framework is that the 3D SS mesh skeleton distributes Li along with the mesh uniformly and provides ample voids to accommodate high Li loading (>10 mA h cm−2), while simultaneously minimizes local current density.

Redox-Driven Lithium Perfusion to Fabricate Li@Ni–Foam Composites for High Lithium-Loading 3D Anodes

As the hostless nature of the conventional Li anodes with planar surfaces inevitably causes volume expansion and parasitic dendrite growth, it is essential to develop composite electrode structure with improved Li plating/stripping behaviors to mitigate such issues. Herein, a composite Li@NF anode was successfully fabricated through lithium perfusion into the commercial nickel foam decorated with lithiophilic NiO nanosheets, demonstrating an exceptionally high areal Li loading of 53.2 mg cm-2 with suppressed Li dendrite formation and volume expansion, improved Coulombic efficiency, as well as extended cycling stability in all half, symmetric and full cell tests. More importantly, DFT calculations and control studies with Fe2O3@NF, pristine-NF and Cu2O@CF reveal a linear correlation between the thermodynamics of the surface reactions and the lithiophilicity of the reaction products, attesting to a redox-driven Li perfusion process. Further through ex-situ scanning electron and in-situ optical microscopy, the enhanced performance of Li@NF is mainly attributed to the mediation of Li plating/stripping through homogenizing the Li+ flux, decentralizing local charge density, and accommodating multi-directional Li deposition by the conductive 3D scaffolds. Consequently, this study offers important insights into the driving of thermal Li perfusion through appropriate material and surface design for achieving safe and stable lithium metal anodes.

Conducting and Lithiophilic MXene/Graphene Framework for High-Capacity, Dendrite-Free Lithium–Metal Anodes

Li-metalanode is widely acknowledged as the ideal anode for high-energy-density batteries, but seriously hindered by the uncontrollable dendrite growth and infinite volume change. Toward this goal, suitable stable scaffolds for dendrite-free Li anodes with large current density (>5 mA cm-2) and high Li loading (>90%) are highly in demand. Herein, a conductive and lithiophilic three-dimensional (3D) MXene/graphene (MG) framework is demonstrated for a dendrite-free Li-metal anode. Benefiting from its high surface area (259 m2 g-1) and lightweight nature with uniformly dispersed lithiophilic MXene nanosheets as Li nucleation sites, the as-formed 3D MG scaffold showcases an ultrahigh Li content (∼92% of the theoretical capacity), as well as strong capabilities in suppressing the Li-dendrite formation and accommodating the volume changes. Consequently, the MG-based electrode exhibits high Coulombic efficiencies (∼99%) with a record lifespan up to 2700 h and is stable for 230 cycles at an ultrahigh current density of 20 mA cm-2. When coupled with Li4Ti5O12 or sulfur, the MG-Li/Li4Ti5O12 full-cell offers an enhanced capacity of 142 mAh g-1 after 450 cycles, while the MG-Li/sulfur cell delivers an improved rate performance, implying the great potential of this 3D MG framework for building long-lifetime, high-energy-density batteries.

Optimum lithium loading of a liquid scintillator for neutron and neutrino detection

Neutral particle detection in high-background environments is greatly aided by the ability to easily load 6Li into liquid scintillators. We describe a readily available and inexpensive liquid scintillation cocktail stably loaded with a Li mass fraction up to 1%. Compositions that give thermodynamically stable microemulsions (reverse-micellar systems) were explored, using a Compton spectrum quenching technique to distinguish these from unstable emulsions. Scintillation light yield and transmittance were characterized. Pulse shape discrimination (PSD) was measured using a 252Cf source, showing that electron-like and proton-like recoil events are well-resolved even for Li loading up to 1%, providing a means of background suppression in neutron/neutrino detectors. While samples in this work were prepared with natLi (7.59% 6Li), the neutron capture peak was clearly visible in the PSD spectrum; this implies that while extremely high capture efficiency could be achieved with 6Li-enriched material, a very inexpensive neutron-sensitive detector can be prepared with natLi.

Synergistic Effect of 3D Current Collectors and ALD Surface Modification for High Coulombic Efficiency Lithium Metal Anodes

Improving the performance of Li metal anodes is a critical bottleneck to enable next‐generation battery systems beyond Li‐ion. However, stability issues originating from undesirable electrode/electrolyte interactions and Li dendrite formation have impaired long‐term cycling of Li metal anodes. In this work, we have developed a bottom‐up fabrication process of vertically aligned and highly uniform Cu pillar arrays on a Cu foil via templated electrodeposition for use as a 3D current collector.[1] By rationally controlling geometric parameters of the 3D current collector architecture, including pillar diameter, spacing, and length, we have demonstrated the morphology of Li plating/stripping upon cycling can be controlled and optimal cycling performance can be achieved. In addition, we showed that deposition of an ultrathin layer of ZnO by atomic layer deposition on the current collector surface can facilitate the initial Li nucleation, which dictates the morphology and reversibility of subsequent cycling. This core–shell pillar architecture allows for the effects of geometry and surface chemistry to be decoupled and individually controlled to optimize the electrode performance in a synergistic manner. Using this model platform, we have demonstrated Li metal anodes with Coulombic efficiency up to 99.5% at 0.5 mA/cm2 and 99.4% at 1 mA/cm2, which are among the highest reported values to date. The results gained from this work can thus provide a pathway toward high‐efficiency and long‐cycle life Li metal batteries with reduced excess Li loading. [1] K.-H. Chen, A.J. Sanchez, E. Kazyak, A.L. Davis, N.P. Dasgupta, Adv. Energy Mater. 9, 1802534 (2019).

Lithiated NiCo2O4 Nanorods Anchored on 3D Nickel Foam Enable Homogeneous Li Plating/Stripping for High-Power Dendrite-Free Lithium Metal Anode.

Lithium (Li) metal is one of the promising anode materials in the next-generation high-energy batteries, but Li dendrite growth and a big volume change during cycling result in low Coulombic efficiency (CE), short lifespan, and safety hazards, thereby impeding practical implementation of Li in rechargeable batteries. Herein, we report a highly stable and dendrite-free Li metal anode based on a three-dimensional (3D) conductive and lithiophilic scaffold comprising lithiated NiCo2O4 nanorods grown on nickel foam (LNCO/Ni). The nanorods grown on 3D Ni foam with a large surface area effectively reduce the averaged electrical current in the electrode, and the conformal Li2O coating produced in situ on the lithiated NiCo2O4 nanorods provides the surface lithiophilicity enabling stable Li plating/stripping without Li dendrite growth even at a high current density of 5 mA cm-2. The LNCO/Ni-Li anode shows a low voltage hysteresis of 16 mV, high CE of 98.7%, and stable cycling without obvious voltage fluctuation for over 500 cycles (1000 h) at a current density of 1 mA cm-2. Specifically, for a scalable Li loading of 20 mA h cm-2 on LNCO/Ni, no growth of Li dendrite and electrode thickness fluctuations are observed. The full cell consisting of the LNCO/Ni-Li anode and the LiFePO4 cathode exhibits a high rate capability and CE as high as 99.6% for more than 160 cycles. Our study reveals a new strategy to develop stable Li-metal anodes for high-energy batteries.

Superlithiophilic Amorphous SiO2-TiO2 Distributed into Porous Carbon Skeleton Enabling Uniform Lithium Deposition for Stable Lithium Metal Batteries.

Lithium (Li) metal anodes have garnered increasing interest in recent years as its high theoretical capacity and low electrochemical potential promises a myriad of opportunities for various applications. However, one critical issue to overcome is the inhomogeneous deposition of Li+ during the plating and stripping process. This inhomogeneous deposition could result in uncontrollable dendrite growth, further leading to poor coulombic efficiency, shorter lifecycles, and safety concerns due to internal short circuit and thermal runaways. To address these issues, a 3D porous core–shell fiber scaffold is presented, comprising of well‐dispersed SiO2, TiO2, and carbon, as superlithiophilic host materials for lithium anodes. The amorphous SiO2 and TiO2 allow for controllable nucleation and deposition of metal Li inside the porous core–shell fiber even at ultrahigh current densities of 10 mA cm−2. In addition, the interconnected conductive fiber with high porosity enables good electrical conductivity with fast ion transport and excellent mechanical strength to withstand massive Li loading during repeated cycles of stripping and plating. As a result, excellent cycling performance and high rate capability are observed in both symmetric cells and full cells, highlighting the feasibility of the proposed Li anode composite.

Ironing Controllable Lithium into Lithiotropic Carbon Fiber Fabric: A Novel Li-Metal Anode with Improved Cyclability and Dendrite Suppression.

Lithium metal as an anode in lithium-ion batteries is attracting more attention because of the high gravimetric/volumetric energy density and low electrochemical potential. However, the irreversible Li plating/striping can reduce the cycling capability and very possibly introduce dendrite growth, thus leading to a series of issues such as infinite volume change, low Coulombic efficiency, and uncontrollable solid electrolyte interphase. Here, we report a novel, single-side Li-infused carbon fiber fabric (LiCFF) with a controllable, minimized Li loading, which shows a highly reversible plating/stripping with an extremely low overpotential of less than 30 mV (Li foil: >1.0 V over 50 cycles) upon >3000 cycles (6000 and 2000 h) at 1 and 3 mA/cm2 in symmetric cells, respectively. With a high areal capacity up to 10 mA h/cm2 and a high current density of 10 mA/cm2, the cell still shows a minimum overpotential of 150-175 mV after 250 cycles (500 h). Full-cell batteries using the LiCFF as "all-in-one" anodes without the additional slurry-making process and nickel-manganese-cobalt oxide (NMC) as cathodes exhibit an improved capacity retention when compared with Li foil: 32% at 0.5 C and 119% at 1.0 C capacity improved after 100 cycles. In parallel, the mossy/dendritic Li on the LiCFF was largely suppressed, which was confirmed using in situ observations of Li plating/striping in a capillary cell. The excellent electronic conductivity of the carbon fabric leads to small contact/transfer resistances of 3.4/3.8 Ω (Li foil: 4.1/44.4 Ω), enabling a drastically lowered energy barrier for Li nucleation/growth. Thus, a uniform current distribution results in forming a homogeneous Li layer instead of forming dendrites. The current LiCFF as the anode with controllable Li (n/p ratio), improved cycling stability, mitigated dendrite formation, and flexibility displays promising applications in versatile Li-metal batteries such as Li-NMC, Li-S, and Li-O2.