Dendrite-free Lithium Metal Batteries Research Articles

Achieving Dendrite-Free Lithium Metal Batteries by Constructing a Dense Lithiophilic Cu1.8Se/CuO Heterojunction Tip.

Lithium (Li)metal batteries (LMBs) have garnered widespread attention due to their high specific capacity. However, the growth of lithium dendrite severely limits their practical applications. Herein, a novel strategy is proposed to regulate the overall potential strength and lithium ions (Li+) concentration on the surface of the current collector by utilizing densely distributed tip effects. This concept is exemplified through the construction of lithiophilic Cu1.8Se/CuO heterojunction needle array on the Cu foil, ultimately achieving dendrite-free lithium deposition. Based on the simulation in COMSOL multiphysics and experimental research, this design is demonstrated to enrich Li+ on the current collector surface, delay the formation of space charge regions, and mitigate the growth of lithium dendrites. Additionally, a built-in electric field (BIEF) triggered by the heterointerface between Cu1.8Se and CuO further alleviates the Li+ concentration gradient on the electrode surface, achieving uniform bottom-up deposition of Li within the array structure. Consequently, the symmetrical cell exhibits an ultra-long cycle life of 2400h (1mAcm-2, 1mAhcm-2) with an extremely low overpotential of 13mV. Furthermore, full batteries using LiFePO4 as the cathode exhibit superior cycle stability and rate performance. This study presents a promising approach for designing dendrite-free current collectors in LMBs.

H3PO4-Impregnated Covalent Organic Framework Membrane on Separators to Prevent Lithium Metal Anode Dendrite Growth.

Inhibiting the growth of lithium dendrites is crucial for battery safety. For separators, their favorable electrolyte wettability, uniform current density, and high ionic conductivity are beneficial for avoiding Li dendrite growth. In this work, we propose a separator (PA@COF/PP) by modifying a polypropylene separator with H3PO4-functionalized covalent organic frameworks. The uniform channels of the covalent organic frameworks and H3PO4 can homogenize the current and act as ionic conductors for efficient Li+ migration. The synthesized separator effectively suppresses the growth of lithium dendrites and improves the stability of the batteries. A symmetric cell with the PA@COF/PP separator exhibits a stable life span over 4000 hours at a high current density of 5 mA cm-2, compared to the commercial PP separator, which lasts only 159 hours. This work provides an efficient method and novel inspiration for the construction of dendrite-free lithium metal batteries.

Core-shell nanofiber separator incorporated with PDA-PEI co-modified Li0.33La0.57TiO3 nanowires prepared by co-axial electrospinning for dendrite-free lithium metal batteries

The core-shell nanofibers containing PDA-PEI co-modified Li0.33La0.57TiO3 (LLTO) perovskite nanowires in the shell layer were fabricated by co-axial electrospinning technique to apply as separator in dendrite-free lithium metal batteries. The PVDF-HFP with good mechanical properties and polar C–F bonds was used as the core material, and polyacrylonitrile (PAN) with high thermal stability was employed as the shell layer in nanofibers. The PDA-PEI co-modified Li0.33La0.57TiO3 nanowires, reacting with PF6− anions in LiPF6 salt can not only capture free anions but also provide a lithium-ion migration pathway. Moreover, the core-shell structured nanofibers exhibited high mechanical strength (9.2 N/mm2), robust thermal stability (>0% at 200 °C for 1 h), and favorable electrolyte affinity (electrolyte uptake of 732%). Gelation of PVDF-HFP in liquid electrolyte leads to high-ionic conductivity (3.52 mS/cm), Li+ transference number (tLi+ = 0.68), uniform Li+ flux, and smooth Li deposition. The Li plating/stripping test consisting of Li–Li cells (with CS/LLTO-PDA-PEI) carried out at 0.4 mA/cm2 was conducted for 1000 h without a short circuit. NCM-Li and NCM-Gr coin cells using the CS (core-shell)/LLTO-PDA-PEI separator retained long-term cycle stability and good Coulombic efficiency (CE).

Dynamically reversible cross-linked polymer electrolytes with highly ionic conductivity for dendrite-free lithium metal batteries

High-safety PEO-based electrolytes have attracted widespread attention, but their inefficient conduction of Li ions and poor contact with electrode interfaces deteriorate the performances of rechargeable lithium metal batteries. Herein, we design a vitrimer polymer electrolyte (V-SPE-PEG) with abundant dynamic imine bonds via Schiff base reaction between aldehyde and ammonia, which achieves high ionic conductivity and good interfacial compatibility with lithium anode. The dynamic polymer network in V-SPE-PEG exhibits solid-state plasticity because reversible imine bonding reactions enable the integrity of the polymer network to be maintained while altering the cross-linked points under external stimuli. Therefore, this 3D dynamic cross-linked network effectively facilitates the polymer chain dynamics and meanwhile enhances ionic conductivity. Additionally, dynamic bond exchange fosters electrolyte flowability and self-healing during lithium deposition, promoting a tightly integrated electrode/electrolyte interface while inhibiting lithium dendrites growth. Consequently, lithium symmetric cells utilizing the V-SPE-PEG electrolyte demonstrate exceptional long-term cycling stability, surpassing 1100 h and exhibit outstanding ionic conductivity of 2.7 × 10−4 S cm−1 at 30 °C. The LiFePO4||Li battery maintains stable cycling performance at both 40 °C and 60 °C. This study introduces an innovative approach to designing solid-state electrolytes for lithium-metal batteries.

In-situ coating strategy to synthesize ultra-soft sulfide solid-state electrolytes for dendrite-free lithium metal batteries

High energy density lithium metal batteries play a crucial role in future energy storage. High ionic conductivity argyrodite-type Li5.5PS4.5Cl1.5 is a promising candidate for future lithium metal all-solid-state batteries. However, under cold pressing conditions, the combination of high electronic conductivity and high porosity significantly accelerates the growth of lithium dendrites, resulting in low capacity and a short lifespan. In this study, we combined a simple wet ball milling and in-situ polymerization process to fabricate a polyvinylene carbonate-coated sulfide composite solid electrolyte. The ultra-soft particle, when cold-pressed without binders, completed a tightly packed and void-free internal structure. This electrolyte, combined with a stable LiF-rich interface layer on lithium metal, held a higher critical current density of 2.0 mA cm−2 than 0.65 mA cm−2 of uncoated argyrodite and a 2000-hour stable cycle at 0.5 mA cm−2 in lithium symmetric cells. The unique coating structure also mitigated the chemomechanical failure between electrolyte and electrode, preventing the rapid increase of interface impedance and achieving a high initial capacity of 173.5 mAh g−1 without a short circuit for 300 cycles in LiNi0.6Co0.2Mn0.2O2//Li cells.

Excellent Polymerized Ionic-Liquid-Based Gel Polymer Electrolytes Enabled by Molecular Structure Design and Anion-Derived Interfacial Layer.

Polymerized ionic liquid (PIL)-based gel polymer electrolytes (GPEs) are well known as highly safe and stable electrolytes but with low ambient ionic conductivity. Herein, we first designed and synthesized an IL monomer with a long and flexible side chain and then mixed it with LiTFSI and MEMPTFSI to construct a PIL-based GPE (denoted as GM-GPE). The special molecular structure of the monomer greatly improves the ionic transport through the PIL chain, and the introduction of MEMPTFSI plasticizer further improves the ionic conductivity, promoting a TFSI--anion-derived SEI formation to suppress Li dendrite growth and forming an electrostatic shielding effect of MEMP+ cations to promote the uniform deposition of Li+. Consequently, the as-prepared GM-GPE exhibits high ambient ionic conductivity (4.3 × 10-4 S cm-1, 30 °C), robust electrochemical stability, excellent thermal stability, nonflammability, and superior ability to inhibit Li dendrite growth. The resultant LiFePO4|GM-GPE|Li cell exhibits a high discharge capacity of 150 mA h g-1 at 0.2 C along with a good cycling stability and rate capability. This work brings about new guidance for the development of high-quality GPEs with high ionic conductivity, high stability, and safety for long cycling and dendrite-free lithium metal batteries.

Flexible self-supporting inorganic nanofiber membrane-reinforced solid-state electrolyte for dendrite-free lithium metal batteries.

Compounding of suitable fillers with PEO-based polymers is the key to forming high-performance electrolytes with robust network structures and homogeneous Li+-transport channels. In this work, we innovatively and efficiently prepared Al2O3 nanofibers and deposited an aqueous dispersion of Al2O3 into a membrane via vacuum filtration to construct a nanofiber membrane with a three-dimensional (3D) network structure as the backbone of a PEO-based solid-state electrolyte. The supporting effect of the nanofiber network structure improved the mechanical properties of the reinforced composite solid-state electrolyte and its ability to inhibit the growth of Li dendrites. Meanwhile, interconnected nanofibers in the PEO-based electrolyte and the strong Lewis acid-base interactions between the chemical groups on the surface of the inorganic filler and the ionic species in the PEO matrix provided facilitated pathways for Li+ transport and regulated the uniform deposition of Li+. Moreover, the interaction between Al2O3 and lithium salts as well as the PEO polymer increased free Li+ concentration and maintained its stable electrochemical properties. Hence, assembled Li/Li symmetric cells achieved a cycle life of more than 2000 h. LFP/Li and NMC811/Li cells provided high discharge specific capacities of up to 146.9 mA h g-1 (0.5C and 50 °C) and 166.9 mA h g-1 (0.25C and 50 °C), respectively. The prepared flexible self-supporting 3D nanofiber network structure construction can provide a simple and efficient new strategy for the exploitation of high-performance solid-state electrolytes.

Magnesium fluoride-engineered UiO-66 artificial protection layers for dendrite-free lithium metal batteries

The MgF2 and F-terminated groups effectively infiltrated the ion transport channels within UiO-66, thereby regulating the desolvation process and facilitating rapid Li+ transport kinetics.

Ultralight Ag-grid current collector enabled by screen printing Ag ink on Cu foil as efficient deposition-inducing layer for dendrite-free lithium metal batteries

An ultralight deposition-inducing layer consisting of a grid-like Ag pattern on Cu foil was designed and fabricated by using a scalable screen-printing technique to guide a uniform lithium-plating behavior.

Multifunctional single-ion conductor-integrated PEO-based solid polymer electrolytes endow highly stable and dendrite-free lithium metal batteries

Poly(ethylene oxide) (PEO) based solid polymer electrolytes (SPEs) hold great promise for circumventing the safety issues caused by liquid electrolytes, which are widely used as one of the leading technical strategies for constructing solid-state lithium metal batteries (LMBs). Unfortunately, developing PEO-based SPEs applicable to high-performance LMBs remains challenging due to the uncontrolled formation of lithium dendrites and sluggish ion migration. In this study, we present the fabrication of highly conductive and mechanically robust composite SPEs (CSPEs) for use in dendrite-proof LMBs by adding a new bis(sulphonyl)imide-based single-ion conductor (LiPEBI) as functional polymer fillers into PEO SPEs network. As expected, the as-prepared CSPEs can simultaneously achieve an excellent mechanical strength of 2.1 MPa, a considerable elongation at a break of 1491.0%, and an optimized degree of crystallization of 37.1%. In addition, introducing the LiPEBI additive promotes the homogeneous distribution of Li-ions and accelerates the ionic transport, resulting in an enhanced ionic conductivity of 4.17 × 10−4 S cm−1 and lithium ion transference number (tLi+) of 0.45 at 60 °C for CSPEs. Such comprehensive physical and electrochemical performances are favorable to suppressing lithium dendrite growth and prolonging the lifespan of LMBs. As a result, the Li||Li symmetrical cells assembled by the CSPEs display a remarkably stable cyclic performance with an extremely low voltage polarization of 60.3 mV over 500 h under 50 μA cm−2 at 60 °C. Also, the CSPEs-based Li||LiFePO4 batteries illustrate superior rate performance up to 1 C and deliver long-term cycling stability with a high discharge capacity of 128.8 mAh g−1 after 100 cycles under 0.4 C at 60 °C. We believe the novel CSPEs have great potential for actual application in the construction of high-safety and dendrite-free solid-state LMBs.

Highly conductive and nonflammable boron-based gel type single ion conducting electrolyte membranes toward high-safety and dendrite-free lithium metal batteries

Single-ion conducting polymer electrolytes (SIPEs), having a high Li-ion transference number (tLi+) close to unity, hold great promise for circumventing the lithium dendrite growth of lithium metal batteries (LMBs). However, SIPEs synthesized by a simple method that also simultaneously fulfill the requirements of high ionic conductivity, good thermal stability, and remarkable fire resistance are still quite rare. Herein, a novel single-ion conducting fibrous membrane (es-DDBSB-Li) based on borate anions of single-ion conductors (denoted as DDBSB-Li) and poly(vinylidene fluoride-hexafluoropropylene) P(VDF-HFP) as a binder was prepared via facile electrospinning technology. The introduction of borate anions promotes the homogeneous distribution of highly concentrated Li-ions and accelerates the ionic migration, leading to an enhanced ionic conductivity of 3.75 × 10−4 S cm−1 at 25 °C for DDBSB-Li saturated with organic solvents. Additionally, the thermally stable and nonflammable DDBSB-Li endows the resultant fibrous membranes to possess good high-temperature stability and fire-resistance properties. The Li||Li cell using this electrolyte displays a high tLi+ of 0.91 and effectively mitigates concentration polarization, thereby enabling a remarkably stable cyclic performance over 2000 h at 2.5 mA cm−2 at 25 °C. Also, this gel SIPE-based Li||LiFePO4 battery demonstrates superior rate performances up to 3C and delivers long-term cycling durability over 600 cycles under 1C at 25 °C. We believe this novel gel SIPE-based fibrous membrane has great potential for practical application in high-safety and dendrite-proof LMBs.

Rationally Designed Fluorinated Polycation Electrolytes for High-Rate, Dendrite-Free Lithium Metal Batteries.

The investigation of high-performance polymer-based electrolytes holds significant importance for advancing the development of next-generation lithium metal batteries (LMBs). In this work, a quasi-solid-state electrolyte (EFA-G) comprising pyrrolidinium type polymeric ionic liquids and fluoropolymers was synthesized through a photoinitiated free radical copolymerization process in the presence of solvate ionic liquids. EFA-G not only exhibited high ionic conductivity (9.87 × 10-4 S cm-1) but also had a wide electrochemical stability window (0-5.0 V vs Li+/Li). The improvement in Li+ transport number (tLi+ = 0.33) of EFA-G was attributed to the enhancement of the Li+ migration ability and the hindrance of anion mobility. Due to the shielding effect of the polymeric ionic liquid on the lithium electrode and the formation of a LiF-rich solid electrolyte interphase (SEI), EFA-G supported stable long-term plating/stripping cycling (>1000 h) of lithium symmetric cells. Li/LFP cells assembled with EFA-G at 30 °C exhibited excellent battery performance with a discharge specific capacity of 78.1 mA h g-1 at 8 C and long cycling life (>600 cycles) with high discharge specific capacity (127.8 mA h g-1 after 600 cycles). EFA-G also enabled decent performance for high-voltage cathode batteries. This work provides insights into the design of high-performance polymer-based electrolytes for LMBs.

Ultra-Uniform and Functionalized Nano-Ion Divider for Regulating Ion Distribution toward Dendrite-Free Lithium Metal Batteries.

Ionic dividers with uniform pores and functionalized surfaces display significant potential for solving Li dendrite issues in Li metal bstteries. In this study, we designed and fabricated single metal and nitrogen co-doped carbon-sandwiched MXene (M-NC@MXene) nanosheets that possess highly ordered nanochannels with a diameter of ∼10nm. The experiments and computational calculations verified that the M-NC@MXene nanosheets eliminate Li dendrites in several ways: (1) redistributing the Li-ion flux via the highly ordered ion channels, (2) selectively conducting Li ions and anchoring anions by heteroatom doping to extend the nucleation time for Li dendrite, and (3) tightly staggering on a routine polypropylene (PP) separator to obstruct the growth path of Li dendrites. With a Zn-NC@MXene-coated PP divider, the assembled Li||Li symmetric battery showed an ultra-low overpotential of ∼25mV and a cycle life of 1500h at a high current density of 3mA cm-2 and high capacity of 3 mAh cm-2 . Remarkably, the life of the Li||Ni83 pouch cell with an energy density of 305Wh kg-1 was improved by five-fold. Moreover, the remarkable performance of Li||Li, Li||LiFePO4 , and Li||Sulfur batteries revealed the significant potential of the well-designed multifunctional ion divider for further practical applications. This article is protected by copyright. All rights reserved.

Single-ion conductors functionalized graphene oxide enabling solid polymer electrolytes with uniform Li-ion transport toward stable and dendrite-free lithium metal batteries

The utilization of poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) has long been deemed promising for the application of state-of-the-art lithium metal metals (LMBs), but still severely impeded by the insufficient Li-ion transporting channels and inhomogeneous Li deposition. Herein, the design of single-ion conductors (PSLi) modified graphene oxide nanosheets (GO-PSLi)-reinforced PEO-based SPEs to address these long-standing issues is proposed. The electronegative sulfonate-rich groups with lithiophilic features on GO-PSLi surface not only effectively enhance the dispersion of nanoparticles within the PEO matrix, but also provide fast Li-ion diffusion pathways. Meanwhile, introducing PSLi chains is also favorable to highly reducing the crystallization of composite SPEs through hydrogen interactions derived from the desired amide functional groups. This, in turn, facilitates segmental relaxation of the PEO backbone, leading to accelerates the Li-ion migration. As a proof of concept, the as-prepared composite SPEs demonstrate a good ionic conductivity of 2.2 × 10−4 S cm−1 and a high lithium transference number of 0.53, significantly outperforming the pure PEO SPEs (1.0 × 10−4 S cm−1 and 0.28, respectively) at 60 °C. In addition, the symmetrical Li||Li cells based on the composite SPEs show excellent reversible lithium plating/stripping performances with dendrite-free uniform lithium deposition over 1100 h under a current of 0.1 mA cm−2 at 60 °C. The Li||LiFePO4 batteries also achieve an impressive capacity of 120.2 mAh g−1 at a high current density of 4C and deliver remarkable cycling abilities with 84.6% retention after 250 cycles under 1C at 60 °C. This study offers a facile and practical strategy to develop advanced composite PEO-based SPEs for safe and dendrite-free solid-state LMBs.

Li3Bi/Li2O layer with uniform built-in electric field distribution for dendrite free lithium metal batteries

Lithium metal batteries have garnered significant attention as a promising energy storage technology, offering high energy density and potential applications across various industries. However, the formation of lithium dendrites during battery cycling poses a considerable challenge, leading to performance degradation and safety hazards. This study aims to address this issue by investigating the effectiveness of a protective layer on the lithium metal surface in inhibiting dendrite growth.The hypothesis is that continuous lithium consumption during battery cycling is a primary contributor to dendrite formation. To test this hypothesis, a protective layer of Li3Bi/Li2O was applied to the lithium foil through immersion in a BiN3O9 solution. Experimental techniques including kelvin probe force microscopy (KPFM) and density functional theory (DFT) calculations were employed to analyze the structural and electronic properties of the Li3Bi/Li2O layer.The findings demonstrate successful doping of Bi into the Li coating, forming Bi-Bi and Bi-O bonds. KPFM measurements reveal a higher work function of Li3Bi/Li2O, indicating its potential as an effective protective layer. DFT calculations further support this observation by revealing a greater adsorption energy of lithium on the Li3Bi/Li2O layer compared to the bulk material. Charge density analysis suggests that the adsorption of Li atoms onto the Li3Bi/Li2O layer induces a redistribution of charge, resulting in increased electron availability on the surface and preventing electrode–electrolyte contact.This study provides insights into the role of the Li3Bi/Li2O protective layer in inhibiting dendrite growth in lithium metal batteries. By mitigating dendrite formation, the protective layer holds promise for enhancing battery performance and longevity. These findings contribute to the development of strategies for improving the stability and reliability of lithium metal batteries, facilitating their wider adoption in energy storage applications.

Plant Leaf-Inspired Separators with Hierarchical Structure and Exquisite Fluidic Channels for Dendrite-Free Lithium Metal Batteries.

Lithium (Li) metal batteries are among the most promising devices for high energy storage applications but suffer from severe and irregular Li dendrite growth. Here, it is demonstrated that the issue can be well tackled by precisely designing the leaf-like membrane with hierarchical structure and exquisite fluidic channels. As a proof of concept, plant leaf-inspired membrane (PLIM) separators are prepared using natural attapulgite nanorods. The PLIM separators feature super-electrolyte-philicity, high thermal stability and high ion-selectivity. Thus, the separators can guide uniform and directed Li growth on the Li anode. The Li//PLIM//Li cell with limited Li anode shows high Coulombic efficiency and cycling stability over 1500h with small overpotential and interface impedance. The Li//PLIM//S battery exhibits high initial capacity (1352 mAh g-1 ), cycling stability (0.019% capacity decay per cycle at 1 C over 500 cycles), rate performance (673 mAh g-1 at 4 C), and high operating temperature (65°C). The separators can also effectively improve reversibility and cycling stability of the Li/Li cell and Li//LFP battery with carbonate-based electrolyte. As such, this work provides fresh insights into the design of bioinspired separators for dendrite-free metal batteries.

Initiator-free in-situ synthesized polymer electrolytes with high ionic conductivity for dendrite-free lithium metal batteries

In-situ preparation of polymer electrolytes (PEs) can enhance electrolyte/electrode interface contact and accommodate the current large-scale production line of lithium-ion batteries (LIBs). However, reactive initiators of in-situ PEs may lead to low capacity, increased impedance and poor cycling performance. Flammable and volatile monomers and plasticizers of in-situ PEs are potential safety risks for the batteries. Herein, we adopt lithium difluoro(oxalate)borate (LiDFOB)-initiated in-situ polymerization of solid-state non-volatile monomer 1,3,5-trioxane (TXE) to fabricate PEs (In-situ PTXE). Fluoroethylene carbonate (FEC) and methyl 2,2,2-trifluoroethyl carbonate (FEMC) with good fire retardance, high flash point, wide electrochemical window and high dielectric constant were introduced as plasticizers to improve ionic conductivity and flame retardant property of In-situ PTXE. Compared with previously reported in-situ PEs, In-situ PTXE exhibits distinct merits, including free of initiators, non-volatile precursors, high ionic conductivity of 3.76 × 10−3 S cm−1, high lithium-ion transference number of 0.76, wide electrochemical stability window (ESW) of 6.06 V, excellent electrolyte/electrode interface stability and effectively inhibition of Li dendrite growth on the lithium metal anode. The fabricated LiFePO4 (LFP)/Li batteries with In-situ PTXE achieve significantly boosted cycle stability (capacity retention rate of 90.4% after 560 cycles) and outstanding rate capability (discharge capacity of 111.7 mAh g−1 at 3C rate).

2D sp2-carbon-linked covalent organic frameworks as artificial SEI film for dendrite-free lithium metal batteries

2D sp2-carbon-linked covalent organic frameworks as artificial SEI film for dendrite-free lithium metal batteries

A high performance composite separator with robust environmental stability for dendrite-free lithium metal batteries

The garnet ceramic Li6.4La3Zr1.4Ta0.6O12 (LLZTO) modified separators have been proposed to overcome the poor thermal stability and wettability of commercial polyolefin separators. However, the side reaction of LLZTO in the air leads to deterioration of environmental stability of composite separators (PP-LLZTO), which will limit the electrochemical performance of batteries. Herein, the LLZTO with the polydopamine (PDA) coating (LLZTO@PDA) was prepared by solution oxidation, and then applied it to a commercial polyolefin separator to achieve a composite separator (PP-LLZTO@PDA). LLZTO@PDA is stable in the air, and no Li2CO3 can be observed on the surface even after 90 days in the air. Besides, LLZTO@PDA coating endows the PP-LLZTO@PDA separator with the tensile strength (up to 103 MPa), good wettability (contact angle 0°) and high ionic conductivity (0.93 mS cm−1). Consequently, the Li/PP-LLZTO@PDA/Li symmetric cell cycles stably for 600 h without significant dendrites generation, and the assembled Li//LFP cells with PP-LLZTO@PDA-D30 separators deliver a high capacity retention of 91.8% after 200 cycles at 0.1C. This research provides a practical strategy for constructing composite separators with excellent environmental stability and high electrochemical properties.

Bioinspired Separator with Ion-Selective Nanochannels for Lithium Metal Batteries

The free transport of anions through commercial polyolefin separators used in lithium metal batteries (LMBs) gives rise to concentration polarization and rapid growth of lithium dendrites, leading to poor performance and short circuits. Here, a new poly(ethylene-co-acrylic acid) (EAA) separator with functional active sites (i.e., carboxyl groups) distributing along the pore surface was fabricated, forming bioinspired ion-conducting nanochannels within the separator. As the carboxyl groups effectively desolvated Li+ and immobilized anion, the as-prepared EAA separator selectively accelerated the transport of Li+ with transference number of Li+ (tLi+) up to 0.67, which was further confirmed by molecular dynamics simulations. The battery with the EAA separator can be stably cycled over 500 h at 5 mA cm-2. The LMBs with the EAA separator have exceptional electrochemical performance of 107 mAh g-1 at 5 C and a capacity retention of 69% after 200 cycles. This work provides new commercializable separators toward dendrite-free LMBs.