A Highly Reversible,Dendrite-Free Lithium Metal Anode Enabled by a Lithium-Fluoride-Enriched Interphase

Metallic lithium is the most competitive anode material for next-generation lithium (Li)-ion batteries. However, one of its major issues is Li dendrite growth and detachment, which not only causes safety issues, but also continuously consumes electrolyte and Li, leading to low coulombic efficiency (CE) and short cycle life for Li metal batteries. Herein, the Li dendrite growth of metallic lithium anode is suppressed by forming a lithium fluoride (LiF)-enriched solid electrolyte interphase (SEI) through the lithiation of surface-fluorinated mesocarbon microbeads (MCMB-F) anodes. The robust LiF-enriched SEI with high interfacial energy to Li metal effectively promotes planar growth of Li metal on the Li surface and meanwhile prevents its vertical penetration into the LiF-enriched SEI from forming Li dendrites. At a discharge capacity of 1.2 mAh cm⁻², a high CE of >99.2% for Li plating/stripping in FEC-based electrolyte is achieved within 25 cycles. Coupling the pre-lithiated MCMB-F (Li@MCMB-F) anode with a commercial LiFePO₄ cathode at the positive/negative (P/N) capacity ratio of 1:1, the LiFePO₄//Li@MCMB-F cells can be charged/discharged at a high areal capacity of 2.4 mAh cm⁻² for 110 times at a negligible capacity decay of 0.01% per cycle.     

Ultrahigh coulombic efficiency electrolyte enables Li||SPAN batteries with superior cycling performance

Raising the coulombic efficiency of lithium metal anode cycling is the deciding step in realizing long-life rechargeable lithium batteries. Here, we designed a highly concentrated salt/ether electrolyte diluted in a fluorinated ether: 1.8 M LiFSI in DEE/BTFE (diethyl ether/bis(2,2,2-trifluoroethyl)ether), which realized an average coulombic efficiency of 99.37% at 0.5 mA cm⁻² and 1 mAh cm⁻² for more than 900 cycles. This electrolyte also maintained a record coulombic efficiency of 98.7% at 10 mA cm⁻², indicative of its ability to provide fast-charging with high cathode loadings. Morphological studies reveal dense, dendrite free Li depositions after prolonged cycling, while surface analyses confirmed the formation of a robust LiF-rich SEI layer on the cycled Li surface. Moreover, we discovered that this ether-based electrolyte is highly compatible with the low-cost, high-capacity SPAN (Sulfurized polyacrylonitrile) cathode, where the constructed Li||SPAN cell exhibited reversible cathode capacity of 579 mAh g⁻¹ and no capacity decay after 1200 cycles. A cell where a high areal loading SPAN electrode (>3.5 mAh cm⁻²) is paired with only onefold excess Li was constructed and cycled at 1.75 mA cm⁻², maintaining a coulombic efficiency of 99.30% for the lithium metal. Computational simulations revealed that at saturation, the Li-FSI complex forms contact ion pairs, with a first solvation shell comprising DEE molecules, and a second solvation shell with a mix of DEE/BTFE. This study provides a path to enable high energy density Li||SPAN batteries with stable cycling.     

Regulating Lithium Nucleation via CNTs Modifying Carbon Cloth Film for Stable Li Metal Anode

Li metal is demonstrated as one of the most promising anode materials for high energy density batteries. However, uncontrollable Li dendrite growth and repeated growth of solid electrolyte interface during the charge/discharge process lead to safety issues and capacity decay, preventing its practical application. To address these issues, an effective strategy is to realize uniform Li nucleation. Here, a stable lithium–scaffold composite electrode (CC/CNT@Li) is designed by melting of lithium metal into 3D interconnected lithiophilic carbon nanotube (CNT) on a porous carbon cloth (CC). The 3D interconnected CNTs successfully change the lithiophobic CC into lithiophilic nature, reducing the polarization of the electrode, ensuring homogenous Li nucleation and continuous smooth Li plating. The CNTs on the surface of CC provide adequate Li nucleation sites and reduce the areal current density to avoid Li dendrite growth. The 3D porous structure of CC/CNT offers enough free room for buffering the huge volume change during Li plating/stripping. The CC/CNT@Li composite anode exhibits dendrite‐free morphology and superior cycling performances over 500 h with low voltage hysteresis of 18, 23, and 71 mV at the current density of 1, 2, and 5 mA cm^?2, respectively.     

Functional Separator Enabled by Covalent Organic Frameworks for High-Performance Li Metal Batteries

Uncontrolled ion transport and susceptible SEI films are the key factors that induce lithium dendrite growth, which hinders the development of lithium metal batteries (LMBs). Herein, a TpPa-2SO₃H covalent organic framework (COF) nanosheet adhered cellulose nanofibers (CNF) on the polypropylene separator (COF@PP) is successfully designed as a battery separator to respond to the aforementioned issues. The COF@PP displays dual-functional characteristics with the aligned nanochannels and abundant functional groups of COFs, which can simultaneously modulate ion transport and SEI film components to build robust lithium metal anodes. The Li//COF@PP//Li symmetric cell exhibits stable cycling over 800 h with low ion diffusion activation energy and fast lithium ion transport kinetics, which effectively suppresses the dendrite growth and improves the stability of Li+ plating/stripping. Moreover, The LiFePO4//Li cells with COF@PP separator deliver a high discharge capacity of 109.6 mAh g⁻¹ even at a high current density of 3 C. And it exhibits excellent cycle stability and high capacity retention due to the robust LiF-rich SEI film induced by COFs. This COFs-based dual-functional separator promotes the practical application of lithium metal batteries.     

Lithiophilic Nanowire Guided Li Deposition in Li Metal Batteries

Lithium (Li) metal batteries (LMBs) provide superior energy densities far beyond current Li-ion batteries (LIBs) but practical applications are hindered by uncontrolled dendrite formation and the build-up of dead Li in “hostless” Li metal anodes. To circumvent these issues, we created a 3D framework of a carbon paper (CP) substrate decorated with lithiophilic nanowires (silicon (Si), germanium (Ge), and SiGe alloy NWs) that provides a robust host for efficient stripping/plating of Li metal. The lithiophilic Li₂₂Si₅, Li₂₂(Si_0.5Ge_0.5)_5, and Li₂₂Ge₅ formed during rapid Li melt infiltration prevented the formation of dead Li and dendrites. Li₂₂Ge₅/Li covered CP hosts delivered the best performance, with the lowest overpotentials of 40 mV (three times lower than pristine Li) when cycled at 1 mA cm⁻²/1 mAh cm⁻² for 1000 h and at 3 mA cm⁻²/3 mAh cm⁻² for 500 h. Ex situ analysis confirmed the ability of the lithiophilic Li₂₂Ge₅ decorated samples to facilitate uniform Li deposition. When paired with sulfur, LiFePO_4, and NMC811 cathodes, the CP-LiGe/Li anodes delivered 200 cycles with 82%, 93%, and 90% capacity retention, respectively. The discovery of the highly stable, lithiophilic NW decorated CP hosts is a promising route toward stable cycling LMBs and provides a new design motif for hosted Li metal anodes.     

The Inducement and “Rejuvenation” of Li Dendrites by Space Confinement and Positive Fe/Co-Sites

The high reactivity of Li metal and the inhomogeneous Li deposition leads to the formation of Li dendrites and “dead” Li, which impedes the performance of Li metal batteries (LMBs) with high energy density. The regulating and guiding the Li dendrite nucleation is a desirable tactic to realize concentrated distribution of Li dendrites instead of completely inhibiting dendrite formation. Here, a Fe-Co-based Prussian blue analog with hollow and open framework (H-PBA) is employed to modify the commercial polypropylene separator (PP@H-PBA). This functional PP@H-PBA can guide the lithium dendrite growth to form uniform lithium deposition and activate the inactive Li. In details, the H-PBA with macroporous structure and open framework can induce the growth of lithium dendrites via space confinement, while the positive Fe/Co-sites lowered by polar cyanide (−CN) of PBA can reactivate the inactive Li. Thus, the Li|PP@H-PBA|Li symmetric cells exhibit long-term stability at 1 mA cm⁻² for 1 mAh cm⁻² over 500 h. And the Li-S batteries with PP@H-PBA deliver favorable cycling performance at 500 mA g⁻¹ for 200 cycles.     

Large‐Scale Modification of Commercial Copper Foil with Lithiophilic Metal Layer for Li Metal Battery

The application and development of lithium metal battery are severely restricted by the uncontrolled growth of lithium dendrite and poor cycle stability. Uniform lithium deposition is the core to solve these problems, but it is difficult to be achieved on commercial Cu collectors. In this work, a simple and commercially viable strategy is utilized for large‐scale preparation of a modified planar Cu collector with lithiophilic Ag nanoparticles by a simple substitution reaction. As a result, the Li metal shows a cobblestone‐like morphology with similar size and uniform distribution rather than Li dendrites. Interestingly, a high‐quality solid electrolyte interphase layer in egg shell‐like morphology with fast ion diffusion channels is formed on the interface of the collector, exhibiting good stability with long‐term cycles. Moreover, at the current density of 1 mA cm^?2 for 1 mAh cm^?2, the Ag modified planar Cu collector shows an ultralow nucleation overpotential (close to 0 mV) and a stable coulombic efficiency of 98.54% for more than 600 cycles as well as long lifespan beyond 900 h in a Li|Cu‐Ag@Li cell, indicating the ability of this method to realize stable Li metal batteries. Finally, full cells paired with LiNi_0.8Co_0.1Mn_0.1O₂ show superior rate performance and stability compared with those paired with Li foil.     

A Dual-Functional Conductive Framework Embedded with TiN-VN Heterostructures for Highly Efficient Polysulfide and Lithium Regulation toward Stable Li–S Full Batteries

Lithium–sulfur (Li–S) batteries are strongly considered as next-generation energy storage systems because of their high energy density. However, the shuttling of lithium polysulfides (LiPS), sluggish reaction kinetics, and uncontrollable Li-dendrite growth severely degrade the electrochemical performance of Li–S batteries. Herein, a dual-functional flexible free-standing carbon nanofiber conductive framework in situ embedded with TiN-VN heterostructures (TiN-VN@CNFs) as an advanced host simultaneously for both the sulfur cathode (S/TiN-VN@CNFs) and the lithium anode (Li/TiN-VN@CNFs) is designed. As cathode host, the TiN-VN@CNFs can offer synergistic function of physical confinement, chemical anchoring, and superb electrocatalysis of LiPS redox reactions. Meanwhile, the well-designed host with excellent lithiophilic feature can realize homogeneous lithium deposition for suppressing dendrite growth. Combined with these merits, the full battery (denoted as S/TiN-VN@CNFs || Li/TiN-VN@CNFs) exhibits remarkable electrochemical properties including high reversible capacity of 1110 mAh g⁻¹ after 100 cycles at 0.2 C and ultralong cycle life over 600 cycles at 2 C. Even with a high sulfur loading of 5.6 mg cm⁻², the full cell can achieve a high areal capacity of 5.5 mAh cm⁻² at 0.1 C. This work paves a new design from theoretical and experimental aspects for fabricating high-energy-density flexible Li–S full batteries.     

Progress on Lithium Dendrite Suppression Strategies from the Interior to Exterior by Hierarchical Structure Designs

Lithium (Li) metal is promising for high energy density batteries due to its low electrochemical potential (?3.04 V) and high specific capacity (3860 mAh g^?1). However, the safety issues impede the commercialization of Li anode batteries. In this work, research of hierarchical structure designs for Li anodes to suppress Li dendrite growth and alleviate volume expansion from the interior (by the 3D current collector and host matrix) to the exterior (by the artificial solid electrolyte interphase (SEI), protective layer, separator, and solid state electrolyte) is concluded. The basic principles for achieving Li dendrite and volume expansion free Li anode are summarized. Following these principles, 3D porous current collector and host matrix are designed to suppress the Li dendrite growth from the interior. Second, artificial SEI, the protective layer, and separator as well as solid‐state electrolyte are constructed to regulate the distribution of current and control the Li nucleation and deposition homogeneously for suppressing the Li dendrite growth from exterior of Li anode. Ultimately, this work puts forward that it is significant to combine the Li dendrite suppression strategies from the interior to exterior by 3D hierarchical structure designs and Li metal modification to achieve excellent cycling and safety performance of Li metal batteries.     

The Synergetic Effect of Lithium Bisoxalatodifluorophosphate and Fluoroethylene Carbonate on Dendrite Suppression for Fast Charging Lithium Metal Batteries

Fluorinated solid‐electrolyte interphase (SEI) derived from fluoroethylene carbonate (FEC) is particularly favored for dendrite suppression in lithium metal batteries because of the high Young's modulus (≈64.9 Gpa) and low electronic conductivity (10^?31 S cm^?1) of LiF. However, the transportation ability of Li⁺ in this fluorinated SEI under high current densities is limited by the low ionic conductivity of LiF (≈10^?12 S cm^?1). Herein, by rational design, 0.1 m lithium bisoxalatodifluorophosphate (LiDFBOP) is adopted to modify fluorinated SEI in FEC based electrolyte for fast charging lithium metal batteries. Benefiting from the synergetic effect of LiDFBOP and FEC, a fluorinated SEI rich in LiF and Li_xPO_yF_z species can be yielded, which can further improve the stability and ionic conductivity of SEI for fast Li⁺ transportation. Meanwhile, the average coulombic efficiency for Li plating/stripping is improved from 92.0% to 96.7%, thus promoting stable cycling of Li||Li symmetrical batteries with dendrite free morphologies, even at high current densities (3.0 mA cm^?2) and high plating/stripping capacities (3.0 mAh cm^?2). More attractively, in practical Li||LiNi_0.6Co_0.2Mn_0.2O₂ batteries, the cycling life at 1C and rate capacities at 6C are also significantly improved. Therefore, the synergetic effect of LiDFBOP and FEC provides great potential for achieving advanced lithium metal batteries with fast charging ability.     

Anchoring and Catalytic Effects of rGO Supported VS2 Nanosheets Enable High-Performance Li–Organosulfur Battery

As a high-energy-density cathode material, organosulfur has great potential for lithium batteries. However, their practical application is plagued by electronic/ionic insulation and sluggish redox kinetics. Hence, our strategy is to design a self-weaving, freestanding host material by introducing reduced graphene oxide–supported VS₂ nanosheets (VS₂-rGO) and carbon nanotubes (CNTs) for lithium–phenyl tetrasulfide (Li–PTS) batteries. Unique host materials not only provide physicochemical confinement of active materials to boost the utilization but also catalyze the conversion of active materials to accelerate redox kinetics. Therefore, Li–PTS cell based on the 3D VS₂-rGO-CNTs (VSGC) host material shows excellent cyclability, with a slow capacity decay rate of 0.08% per cycle over 500 cycles at 0.5 C, and a high areal capacity of 3.1 mAh cm⁻² with the PTS loading of 7.2 mg cm⁻². More importantly, the potential for practical applications is highlighted by the flexible pouch cell with a high areal capacity (4.1 mAh cm⁻²) and a low electrolyte/PTS ratio (3.5 µL mg⁻¹). This work sheds light on elevating the electrochemical performance of Li–organosulfur batteries through the effective catalytic and adsorbed host material.     

Lithiophilic Magnetic Host Facilitates Target-Deposited Lithium for Practical Lithium-Metal Batteries

Lithium-metal shows promising prospects in constructing various high-energy-density lithium-metal batteries (LMBs) while long-lasting tricky issues including the uncontrolled dendritic lithium growth and infinite lithium volume expansion seriously impede the application of LMBs. In this work, it is originally found that a unique lithiophilic magnetic host matrix (Co₃O₄-CCNFs) can simultaneously eliminate the uncontrolled dendritic lithium growth and huge lithium volume expansion that commonly occur in typical LMBs. The magnetic Co₃O₄ nanocrystals which inherently embed on the host matrix act as nucleation sites and can also induce micromagnetic field and facilitate a targeted and ordered lithium deposition behavior thus, eliminating the formation of dendritic Li. Meanwhile, the conductive host can effectively homogenize the current distribution and Li-ion flux, thus, further relieving the volume expansion during cycling. Benefiting from this, the featured electrodes demonstrate ultra-high coulombic efficiency of 99.1% under 1 mA cm⁻² and 1 mAh cm⁻². Symmetric cell under limited Li (10 mAh cm⁻²) inspiringly delivers ultralong cycle life of 1600 h (under 2 mA cm⁻², 1 mAh cm⁻²). Moreover, LiFePO₄||Co₃O₄-CCNFs@Li full-cell under practical condition of limited negative/positive capacity ratio (2.3:1) can deliver remarkably improved cycling stability (with 86.6% capacity retention over 440 cycles).     

3D Printing of a V8C7–VO2 Bifunctional Scaffold as an Effective Polysulfide Immobilizer and Lithium Stabilizer for Li–S Batteries

Lithium–sulfur (Li–S) batteries have heretofore attracted tremendous interest due to low cost and high energy density. In this realm, both the severe shuttling of polysulfide and the uncontrollable growth of dendritic lithium have greatly hindered their commercial viability. Recent years have witnessed the rapid development of rational approaches to simultaneously regulate polysulfide behaviors and restrain lithium dendritic growth. Nevertheless, the major obstacles for high-performance Li–S batteries still lie in little knowledge of bifunctional material candidates and inadequate explorations of advanced technologies for customizable devices. Herein, a “two-in-one” strategy is put forward to elaborate V₈C₇–VO₂ heterostructure scaffolds via the 3D printing (3DP) technique as dual-effective polysulfide immobilizer and lithium dendrite inhibitor for Li–S batteries. A thus-derived 3DP-V₈C₇–VO₂/S electrode demostrates excellent rate capability (643.5 mAh g⁻¹ at 6.0 C) and favorable cycling stability (a capacity decay of 0.061% per cycle at 4.0 C after 900 cycles). Importantly, the integrated Li–S battery harnessing both 3DP hosts realizes high areal capacity under high sulfur loadings (7.36 mAh cm⁻² at a sulfur loading of 9.2 mg cm⁻²). This work offers insight into solving the concurrent challenges for both S cathode and Li anode throughout 3DP.     

A 3D Lithiophilic Mo2N‐Modified Carbon Nanofiber Architecture for Dendrite‐Free Lithium‐Metal Anodes in a Full Cell

The pursuit for high‐energy‐density batteries has inspired the resurgence of metallic lithium (Li) as a promising anode, yet its practical viability is restricted by the uncontrollable Li dendrite growth and huge volume changes during repeated cycling. Herein, a new 3D framework configured with Mo₂N‐mofidied carbon nanofiber (CNF) architecture is established as a Li host via a facile fabrication method. The lithiophilic Mo₂N acts as a homogeneously pre‐planted seed with ultralow Li nucleation overpotential, thus spatially guiding a uniform Li nucleation and deposition in the matrix. The conductive CNF skeleton effectively homogenizes the current distribution and Li‐ion flux, further suppressing Li‐dendrite formation. As a result, the 3D hybrid Mo₂N@CNF structure facilitates a dendrite‐free morphology with greatly alleviated volume expansion, delivering a significantly improved Coulombic efficiency of ≈99.2% over 150 cycles at 4 mA cm^?2. Symmetric cells with Mo₂N@CNF substrates stably operate over 1500 h at 6 mA cm^?2 for 6 mA h cm^?2. Furthermore, full cells paired with LiNi_0.8Co_0.1Mn_0.1O₂ (NMC811) cathodes in conventional carbonate electrolytes achieve a remarkable capacity retention of 90% over 150 cycles. This work sheds new light on the facile design of 3D lithiophilic hosts for dendrite‐free lithium‐metal anodes.     

Shielding Polysulfide Intermediates by an Organosulfur-Containing Solid Electrolyte Interphase on the Lithium Anode in Lithium–Sulfur Batteries

The lithium–sulfur (Li–S) battery is regarded as a promising high-energy-density battery system, in which the dissolution–precipitation redox reactions of the S cathode are critical. However, soluble Li polysulfides (LiPSs), as the indispensable intermediates, easily diffuse to the Li anode and react with the Li metal severely, thus depleting the active materials and inducing the rapid failure of the battery, especially under practical conditions. Herein, an organosulfur-containing solid electrolyte interphase (SEI) is tailored for the stabilizaiton of the Li anode in Li–S batteries by employing 3,5-bis(trifluoromethyl)thiophenol as an electrolyte additive. The organosulfur-containing SEI protects the Li anode from the detrimental reactions with LiPSs and decreases its corrosion. Under practical conditions with a high-loading S cathode (4.5 mg_S cm⁻²), a low electrolyte/S ratio (5.0 µL mg_S⁻¹), and an ultrathin Li anode (50 µm), a Li–S battery delivers 82 cycles with an organosulfur-containing SEI in comparison to 42 cycles with a routine SEI. This work provokes the vital insights into the role of the organic components of SEI in the protection of the Li anode in practical Li–S batteries.     

Coupling a Sponge Metal Fibers Skeleton with In Situ Surface Engineering to Achieve Advanced Electrodes for Flexible Lithium–Sulfur Batteries

Lithium–sulfur batteries (LSBs) are regarded as promising next-generation energy storage systems, however, the uncontrollable dendrite formation and serious polysulfide shuttling severely hinder their commercial success. Herein, a powerful 3D sponge nickel (SN) skeleton plus in situ surface engineering strategy, to address these issues synergistically, is reported, and a high-performance flexible LSB device is constructed. Specifically, the rationally designed spray-quenched lithium metal on the SN matrix (solid electrolyte interface (SEI)@Li/SN), as dendrite inhibitor, combines the merits of the 3D lithiophilic SN skeleton and the in situ formed SEI layer derived from the spray-quenching process, and thereby exhibits a steady overpotential within 75 mV for 1500 h at 5 mA cm⁻²/10 mA h cm⁻². Meanwhile, in situ surface sulfurization of the SN skeleton hybridizing with the carbon/sulfur composite (SC@Ni₃S₂/SN) serves as efficient lithium polysulfide adsorbent to catalyze the overall reaction kinetics. COMSOL Multiphysics simulations and density functional theory calculations are further conducted to explore the underlying mechanisms. As a proof of concept, the well-designed SEI@Li/SN||SC@Ni₃S₂/SN full cell shows excellent electrochemical performance with a negative/positive ratio in capacity of ≈2 and capacity retention of 99.82% at 1 C under mechanical deformation. The novel design principles of these materials and electrodes successfully shed new light on the development of flexible LSBs.     

A Polymer‐Reinforced SEI Layer Induced by a Cyclic Carbonate‐Based Polymer Electrolyte Boosting 4.45 V LiCoO2/Li Metal Batteries

Lithium (Li) metal batteries (LMBs) are enjoying a renaissance due to the high energy densities. However, they still suffer from the problem of uncontrollable Li dendrite and pulverization caused by continuous cracking of solid electrolyte interphase (SEI) layers. To address these issues, developing spontaneously built robust polymer‐reinforced SEI layers during electrochemical conditioning can be a simple yet effective solution. Herein, a robust homopolymer of cyclic carbonate urethane methacrylate is presented as the polymer matrix through an in situ polymerization method, in which cyclic carbonate units can participate in building a stable polymer‐integrated SEI layer during cycling. The as‐investigated gel polymer electrolyte (GPE) assembled LiCoO₂/Li metal batteries exhibit a fantastic cyclability with a capacity retention of 92% after 200 cycles at 0.5 C (1 C = 180 mAh g^?1), evidently exceeding that of the counterpart using liquid electrolytes. It is noted that the anionic ring‐opening polymerization of the cyclic carbonate units on the polymer close to the Li metal anodes enables a mechanically reinforced SEI layer, thus rendering excellent compatibility with Li anodes. The in situ formed polymer‐reinforced SEI layers afford a splendid strategy for developing high voltage resistant GPEs compatible with Li metal anodes toward high energy LMBs.     

Solid-State Electrolyte Design for Lithium Dendrite Suppression

All-solid-state Li metal batteries have attracted extensive attention due to their high safety and high energy density. However, Li dendrite growth in solid-state electrolytes (SSEs) still hinders their application. Current efforts mainly aim to reduce the interfacial resistance, neglecting the intrinsic dendrite-suppression capability of SSEs. Herein, the mechanism for the formation of Li dendrites is investigated, and Li-dendrite-free SSE criteria are reported. To achieve a high dendrite-suppression capability, SSEs should be thermodynamically stable with a high interface energy against Li, and they should have a low electronic conductivity and a high ionic conductivity. A cold-pressed Li₃N–LiF composite is used to validate the Li-dendrite-free design criteria, where the highly ionic conductive Li₃N reduces the Li plating/stripping overpotential, and LiF with high interface energy suppresses dendrites by enhancing the nucleation energy and suppressing the Li penetration into the SSEs. The Li₃N–LiF layer coating on Li₃PS₄ SSE achieves a record-high critical current of >6 mA cm⁻² even at a high capacity of 6.0 mAh cm⁻². The Coulombic efficiency also reaches a record 99% in 150 cycles. The Li₃N–LiF/Li₃PS₄ SSE enables LiCoO₂ cathodes to achieve 101.6 mAh g⁻¹ for 50 cycles. The design principle opens a new opportunity to develop high-energy all-solid-state Li metal batteries.     

Ultrathin Lithiophilic 3D Arrayed Skeleton Enabling Spatial-Selection Deposition for Dendrite-Free Lithium Anodes

Lithium metal batteries are promising to become a new generation of energy storage batteries. However, the growth of Li dendrites and the volume expansion of the anode are serious constraints to their commercial implementation. Herein, a controllable strategy is proposed to construct an ultrathin 3D hierarchical host of honeycomb copper micromesh loaded with lithiophilic copper oxide nanowires (CMMC). The uniquely designed 3D hierarchical arrayed skeletons demonstrate a surface-preferred and spatial-selective effect to homogenize local current density and relieve the volume expansion, effectively suppressing the dendrite growth. Employing the constructed CMMC current collector in a half-cell, >400 cycles with 99% coulombic efficiency at 0.5 mA cm⁻² is performed. The symmetric battery cycles stably for >2000 h, and the full battery delivers a capacity of 166.6 mAh g⁻¹. This facile and controllable approach provides an effective strategy for constructing high-performance lithium metal batteries.     

In Situ Solid Electrolyte Interphase from Spray Quenching on Molten Li: A New Way to Construct High‐Performance Lithium‐Metal Anodes

Uncontrollable growth of Li dendrites and low utilization of active Li severely hinder its practical application. Construction of an artificial solid electrolyte interphase (SEI) on Li is demonstrated as one of the most effective ways to circumvent the above problems. Herein, a novel spray quenching method is developed in situ to fabricate an organic–inorganic composite SEI on Li metal. By spray quenching molten Li in a modified ether‐based solution, a homogeneous and dense SEI consisting of organic matrix embedded with inorganic LiF and Li₃N nanocrystallines (denoted as OIFN) is constructed on Li metal. Arising from high ionic conductivity and strong mechanical stability, the OIFN can not only effectively minimize the corrosion reaction of Li, but also greatly suppresses the dendrite growth. Accordingly, the OIFN‐Li anode presents prominent electrochemical performance with an enhanced Coulombic efficiency of 98.15% for 200 cycles and a small hysteresis of <450 mV even at ultrahigh current density up to 10 mA cm^?2. More importantly, during the full cell test with limited Li source, a high utilization of Li up to 40.5% is achieved for the OIFN‐Li anode. The work provides a brand‐new route to fabricate advanced SEI on alkali metal for high‐performance alkali‐metal batteries.