Building microcracked structure fibrous cathode coated by Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) for ultra-stable fiber-shaped aqueous zinc ions batteries.

Attributing to the advantages of intrinsic safety, high energy density, and good omnidirectional flexibility, fiber-shaped aqueous zinc ions batteries (FAZIBs), serving as energy supply devices, have multitude applications in flexible and wearable electronic devices. However, the detachment of active materials caused by bending stress generated during flexing process limits their practical application severely. To address the above issue, an effective integrated strategy employing microcracked activated cobalt hydroxide [A-Co(OH)2] cathode with protective coating of poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate) (PEDOT:PSS) was proposed in this work to enhance the cyclic and bending performances of FAZIBs. The microcracked A-Co(OH)2 cathode relieves stress concentration under bending conditions, while the PEDOT:PSS coating is responsible to maintain the structural integrity and prevents the detachment of A-Co(OH)2. The FAZIBs based on a gel electrolyte achieved a high energy density (173.5 Wh·kg-1) at a power density 90 W·kg-1 and a bending durability (94.4 % capacity retention after 500 cycles) as a consequence of the synergistic effect of microcracked A-Co(OH)2 cathode and the PEDOT:PSS coating. This work will offer a new approach for devising high-performance FAZIBs and promote the development of highly flexible and stable fiber-shaped batteries.

n-ZrS3/p-ZrOS Photoanodes with NiOOH/FeOOH Oxygen Evolution Catalysts for Photoelectrochemical Water Oxidation.

Photoelectrochemical water splitting offers a promising approach for carbon neutrality, but its commercial prospects are still hampered by a lack of efficient and stable photoelectrodes with earth-abundant materials. Here, we report a strategy to construct an efficient photoanode with a coaxial nanobelt structure, comprising a buried-ZrS3/ZrOS n-p junction, for photoelectrochemical water splitting. The p-type ZrOS layer, formed on the surface of the n-type ZrS3 nanobelt through a pulsed-ozone-treatment method, acts as a hole collection layer for hole extraction and a protective layer to shield the photoanode from photocorrosion. The resulting ZrS3/ZrOS photoanode exhibits light harvesting with good photo-to-current efficiencies across the whole visible region to over 650 nm. By further employing NiOOH/FeOOH as the oxygen evolution reaction cocatalyst, the ZrS3/ZrOS/NiOOH/FeOOH photoanode yields a photocurrent density of ~9.3 mA cm-2 at 1.23 V versus the reversible hydrogen electrode with an applied bias photon-to-current efficiency of ~3.2% under simulated sunlight irradiation in an alkaline solution (pH = 13.6). The conformal ZrOS layer enables ZrS3/ZrOS/NiOOH/FeOOH photoanode operation over 1000 hours in an alkaline solution without obvious performance degradation. This study, offering a promising approach to fabricate efficient and durable photoelectrodes with earth-abundant materials, advances the frontiers of photoelectrochemical water splitting.

Integrating Prelithiation and Interface Protection to Achieve High-Energy All-Solid-State Batteries.

All-solid-state batteries (ASSBs), particularly those with Li-free anodes or even anode-free configurations, have attracted extensive attention due to high safety and energy density. However, chemical-mechanical degradation typically deteriorates the cycle life and energy of Li-free anode ASSBs with the absence of Li inventory. Here, the prelithiation agent Li5FeO4 (LFO) coated Ni-rich layered oxide is developed as the cathode for Li-free anode ASSBs. The coated LFO acts as an interfacial protective layer to prevent the highly oxidizing Ni-rich cathode from reacting with sulfide solid-state electrolytes (SSEs), mitigating the structural degradation of Ni-rich cathodes and the decomposition of SSE, resulting in excellent cycle life. Beneficial from the coated LFO in the cathode of the Li-free anode ASSBs, the reversible capacity improves from 174.7 mAh g-1 to 199.7 mAh g-1, and the capacity retention is enhanced from 33.8% to 84.8% after 100 cycles. Additionally, an ultrahigh energy density of 440 Wh kg-1, based on the mass of the composite cathode, Li-free anode, and SSE, is obtained in a Li-free anode all-solid-state pouch cell equipped with the LFO-coated cathode.

Dendrite Growth and Dead Lithium Formation in Lithium Metal Batteries and Mitigation Using a Protective Layer: A Phase-Field Study.

Lithium metal batteries (LMBs) are considered one of the most promising next-generation rechargeable batteries due to their high specific capacity. However, severe dendrite growth and subsequent formation of dead lithium (Li) during the battery cycling process impede its practical application. Although extensive experimental studies have been conducted to investigate the cycling process, and several theoretical models were developed to simulate the Li dendrite growth, there are limited theoretical studies on the dead Li formation, as well as the entire cycling process. Herein, we developed a phase-field model to simulate both electroplating and stripping process in a bare Li anode and Li anode covered with a protective layer. A step function is introduced in the stripping model to capture the dynamics of dead Li. Our simulation clearly shows the growth of dendrites from a bare Li anode during charging. These dendrites detach from the bulk anode during discharging, forming dead Li. Dendrite growth becomes more severe in subsequent cycles due to enhanced surface roughness of the Li anode, resulting in an increasing amount of dead Li. In addition, it is revealed that dendrites with smaller base diameters detach faster at the base and produce more dead lithium. Meanwhile, the Li anode covered with a protective layer cycles smoothly without forming Li dendrite and dead Li. However, if the protective layer is fractured, Li metal preferentially grows into the crack due to enhanced Li-ion (Li+) flux and forms a dendrite structure after penetration through the protective layer, which accelerates the dead Li formation in the subsequent stripping process. Our work thus provides a fundamental understanding of the mechanism of dead Li formation during the charging/discharging process and sheds light on the importance of the protective layer in the prevention of dead Li in LMBs.

In Situ Inorganic/Organic Protective Layer on Carbon Paper as Advanced Current Collector for Robust Li Metal Anode.

Lithium (Li) metal is regarded as the most promising anode for next-generation batteries with high energy density. However, the uncontrolled dendrite growth and infinite volume expansion during cycling seriously hinder the application of Li metal batteries (LMBs). Herein, an inorganic/organic protective layer (labeled as BPH), composed of in situ formed inorganic constituents and PVDF-HFP, is designed on the 3D carbon paper (CP) surface by hot-dipping method. The BPH layer can effectively improve the mechanical strength and ionic conductivity of the SEI layer, which is beneficial to expedite the Li-ion transfer of the entire framework and achieve stable Li plating/stripping behavior. As a result, the modified 3D CP (BPH-CP) exhibits an ultrahigh average Coulombic efficiency (CE) of ≈99.7% over 400 cycles. Further, the Li||LiFePO4 (LFP) cell exhibits an extremely long-term cycle life of over 3000 cycles at 5 C. Importantly, the full cell with high mass loading LiFePO4 (20 mg cm-2) or LiNi0.8Co0.1Mn0.1O2 (NCM, 16 mg cm-2) cathode exhibits stable cycling for 100 or 150 cycles at 0.5 C with high-capacity retention of 86.5% or 82.0% even at extremely low N/P ratio of 0.88 or 0.94. believe that this work enlightens a simple and effective strategy for the application of high-energy-density and high-rate-C LMBs.

Impact of carbon and platinum protective layers on EDS accuracy in FIB cross-sectional analysis of W/Hf/W thin-film multilayers.

Achieving high-quality cross sections is essential for accurate analysis of multilayer coatings. One method of performing such cross sections is focused ion beam, where sample protection from ion damage in the form of protective layers applied by FEBID and FIBID methods is used. Due to the lack of comparative summaries of different layers applied by these methods, especially in the context of cross-sectional analysis and elemental analysis of the cross-section, it was decided to address the effect of the protective layer on the reliability of EDS analysis. This study compares the effectiveness of platinum and carbon protective layers in creating cross sections for W/Hf/W samples. The effect of protective layers on elemental mapping and elemental analysis accuracy was evaluated. This study highlights the importance of protective layer selection in providing reliable EDS analysis of cross sections.

VO2-Based Spacecraft Smart Radiator with High Emissivity Tunability and Protective Layer.

In the extreme space environment, spacecraft endure dramatic temperature variations that can impair their functionality. A VO2-based smart radiator device (SRD) offers an effective solution by adaptively adjusting its radiative properties. However, current research on VO2-based thermochromic films mainly focuses on optimizing the emissivity tunability (Δε) of single-cycle sandwich structures. Although multi-cycle structures have shown increased Δε compared to single-cycle sandwich structures, there have been few systematic studies to find the optimal cycle structure. This paper theoretically discusses the influence of material properties and cyclic structure on SRD performance using Finite-Difference Time-Domain (FDTD) software, which is a rigorous and powerful tool for modeling nano-scale optical devices. An optimal structural model with maximum emissivity tunability is proposed. The BaF2 obtained through optimization is used as the dielectric material to further optimize the cyclic resonator. The results indicate that the tunability of emissivity can reach as high as 0.7917 when the BaF2/VO2 structure is arranged in three periods. Furthermore, to ensure a longer lifespan for SRD under harsh space conditions, the effects of HfO2 and TiO2 protective layers on the optical performance of composite films are investigated. The results show that when TiO2 is used as the protective layer with a thickness of 0.1 µm, the maximum emissivity tunability reaches 0.7932. Finally, electric field analysis is conducted to prove that the physical mechanism of the smart radiator device is the combination of stacked Fabry-Perot resonance and multiple solar reflections. This work not only validates the effectiveness of the proposed structure in enhancing spacecraft thermal control performance but also provides theoretical guidance for the design and optimization of SRDs for space applications.

Supramolecular Metal-Organic Framework for the High Stability of Aqueous Rechargeable Zinc Batteries.

Aqueous rechargeable Zn batteries (AZBs) are considered to be promising next-generation battery systems. However, the growth of Zn dendrites and water-induced side reactions have hindered their practical application, especially with regard to long-term cyclability. To address these challenges, we introduce a supramolecular metal-organic framework (SMOF) coating layer using an α-cyclodextrin-based MOF (α-CD-MOF-K) and a polymeric binder. The plate-like α-CD-MOF-K particles, combined with the polymeric binder create dense and homogeneous Zn2+ ion conductive pore channels that can vertically transport Zn2+ ions through the cavity while restricting the contact of water molecules. Molecular dynamics (MD) simulation verifies that Zn2+ ions can reversibly migrate through the pores of α-CD-MOF-K by partial dehydration. The uniform Zn deposition/dissolution promotes a smooth solid-electrolyte interface layer on the Zn metal anode and effectively suppresses side reactions with free water molecules. The α-CD-MOF-K@Zn symmetric cell exhibits stable cycling and a small polarization voltage of 70 mV for 800 h at 5 mA cm-2, and the α-CD-MOF-K@Zn|α-MnO2 full cell shows only 0.12% capacity decay per cycle at a rate of 1 A g-1.

Coating Robust Layers on Ni-Rich Cathode Active Materials while Suppressing Cation Mixing for All-Solid-State Lithium-Ion Batteries.

This study focused on addressing the challenges associated with the incompatibility between sulfide solid electrolytes and Ni-rich cathode active materials (CAMs) in all-solid-state lithium-ion batteries. To resolve these issues, protective layers have been explored for Ni-rich materials. Lithium lanthanum titanate (LLTO), a perovskite-type material, is recognized for its excellent chemical stability and ionic conductivity, which render it a potential protective layer in CAMs. However, traditional methods of achieving the perovskite structure involve temperatures exceeding 700 °C, resulting in challenges such as LLTO agglomeration, secondary phase formation between LLTO and CAM, and cation mixing within the CAM. In this study, a rapid technique known as flash-light sintering (FLS) was employed to fabricate a uniform and pure perovskite protective layer without inducing cation mixing within the CAM. The LLTO-coated LiNi0.8Co0.1Mn0.1O2 (NCM811) with FLS treatment demonstrated minimal cation mixing and formed a fully covered dense layer. This resulted in a high initial capacity and effectively addressed the incompatibility issues between the sulfide electrolytes and CAM. The rapid FLS method not only streamlines the fabrication of LLTO-coated NCM811 but also provides opportunities for its broader application to materials that were previously deemed impractical because of high sintering temperatures.

A Protective Layer of UIO-66/Reduced Graphene Oxide to Stabilize Zinc-Metal Anodes toward High-Performance Aqueous Zinc-Ion Batteries.

Rechargeable aqueous Zn-ion batteries with a Zn anode hold great promise as promising candidates for advanced energy storage systems. The construction of protective layer coatings on Zn anode is an effective way to suppress the growth of Zn dendrites and water-induced side reactions. Herein, we reported a series of UIO-66 materials with different concentrations of reduced graphene oxide (rG) coated onto the surface of Zn foil (Zn@UIO-66/rGx; x = 0.05, 0.1, and 0.2). Benefiting from the synergistic effect of UIO-66 and rG, symmetric cells with Zn@UIO-66/rGx (x = 0.1) electrodes exhibit excellent reversibility (e.g., long cycling life over 1100 h at 1 mA cm-2/1 mAh cm-2) and superior rate capability (e.g., over 1100 and 400 h at 5 mA cm-2/2.5 mAh cm-2 and 10 mA cm-2/5 mAh cm-2, respectively). When the Zn@UIO-66/rG0.1 anode was paired with the NaV3O8·1.5H2O (NVO) cathode, the Zn@UIO-66/rG0.1||NVO cell also delivered a high reversible capacity of 189.9 mAh g-1 with an initial capacity retention of 61.3% after 500 cycles at 1 A g-1, compared to the bare Zn||NVO cell with only 92 cycles.

Stabilizing Zinc Anode through Ion Selection Sieving for Aqueous Zn-Ion Batteries.

Uncontrollable dendrite growth and corrosion induced by reactive water molecules and sulfate ions (SO42-) seriously hindered the practical application of aqueous zinc ion batteries (AZIBs). Here we construct artificial solid electrolyte interfaces (SEIs) realized by sodium and calcium bentonite with a layered structure anchored to anodes (NB@Zn and CB@Zn). This artificial SEI layer functioning as a protective coating to isolate activated water molecules, provides high-speed transport channels for Zn2+, and serves as an ionic sieve to repel negatively charged anions while attracting positively charged cations. The theoretical results show that the bentonite electrodes exhibit a higher binding energy for Zn2+. This demonstrates that the bentonite protective layer enhances the Zn-ion deposition kinetics. Consequently, the NB@Zn//MnO2 and CB@Zn//MnO2 full-battery capacities are 96.7 and 70.4 mAh g-1 at 2.0 A g-1 after 1000 cycles, respectively. This study aims to stabilize Zn anodes and improve the electrochemical performance of AZIBs by ion-selection sieving.

Enhancing Zinc Electrode Stability Through Pre-Desolvation and Accelerated Charge Transfer via a Polyimide Interface for Zinc-Ion Batteries.

Aqueous zinc-based energy storage devices possess superior safety, cost-effectiveness, and high energy density; however, dendritic growth and side reactions on the zinc electrode curtail their widespread applications. In this study, these issues are mitigated by introducing a polyimide (PI) nanofabric interfacial layer onto the zinc substrate. Simulations reveal that the PI nanofabric promotes a pre-desolvation process, effectively desolvating hydrated zinc ions from Zn(H2O)6 2+ to Zn(H2O)4 2+ before approaching the zinc surface. The exposed zinc ion in Zn(H2O)4 2+ provides an accelerated charge transfer process and reduces the activation energy for zinc deposition from 40 to 21 kJ mol-1. The PI nanofabric also acts as a protective barrier, reducing side reactions at the electrode. As a result, the PI-Zn symmetric cell exhibits remarkable cycling stability over 1200 h, maintaining a dendrite-free morphology and minimal byproduct formation. Moreover, the cell exhibits high stability and low voltage hysteresis even under high current densities (20 mA cm-2, 10 mAh cm-2) thanks to the 3D porous structure of PI nanofabric. When integrated into full cells, the PI-Zn||AC hybrid zinc-ion capacitor and PI-Zn||MnVOH@SWCNT zinc-ion battery achieve impressive lifespans of 15000 and 600 cycles with outstanding capacitance retention. This approach paves a novel avenue for high-performance zinc metal electrodes.

Constructing Lysozyme Protective Layer via Conformational Transition for Aqueous Zn Batteries.

The practical applications for aqueous Zn ion batteries (ZIBs) are promising yet still impeded by the severe side reactions on Zn metal. Here, a lysozyme protective layer (LPL) is prepared on Zn metal surface by a simple and facile self-adsorption strategy. The LPL exhibits extremely strong adhesion on Zn metal to provide stable interface during long-term cycling. In addition, the self-adsorption strategy triggered by the hydrophobicity-induced aggregation effect endows the protective layer with a gap-free and compacted morphology which can reject free water for effective side reaction inhibition performance. More importantly, the lysozyme conformation is transformed from α-helix to ß-sheet structure before layer formation, thus abundant functional groups are exposed to interact with Zn2+ for electrical double layer (EDL) modification, desolvation energy decrease, and ion diffusion kinetics acceleration. Consequently, the LPL renders the symmetrical Zn battery with ultra-long cycling performance for more than 1200 h under high Zn depth of discharge (DOD) for 77.7%, and the Zn/Zn0.25V2O5 pouch cell with low N/P ratio of 2.1 at high Zn utilization of 48% for over 300 cycles. This study proposes a facile and low-cost method for constructing a stable protective layer of Zn metal for high Zn utilization aqueous devices.

Stable Zinc Anode Facilitated by Regenerated Silk Fibroin-modified Hydrogel Protective Layer.

Inherent dendrite growth and side reactions of zinc anode caused by its unstable interface in aqueous electrolytes severely limit the practical applications of zinc-ion batteries (ZIBs). To overcome these challenges, a protective layer for Zn anode inspired by cytomembrane structure is developed with PVA as framework and silk fibroin gel suspension (SFs) as modifier. This PVA/SFs gel-like layer exerts similar to the solid electrolyte interphase, optimizing the anode-electrolyte interface and Zn2+ solvation structure. Through interface improvement, controlled Zn2+ migration/diffusion, and desolvation, this buffer layer effectively inhibits dendrite growth and side reactions. The additional SFs provide functional improvement and better interaction with PVA by abundant functional groups, achieving a robust and durable Zn anode with high reversibility. Thus, the PVA/SFs@Zn symmetric cell exhibits an ultra-long lifespan of 3150 h compared to bare Zn (182 h) at 1.0 mAh cm-2-1.0 mAh cm-2, and excellent reversibility with an average Coulombic efficiency of 99.04% under a large plating capacity for 800 cycles. Moreover, the PVA/SFs@Zn||PANI/CC full cells maintain over 20 000 cycles with over 80% capacity retention under harsh conditions at 5 and 10 A g-1. This SF-modified protective layer for Zn anode suggests a promising strategy for reliable and high-performance ZIBs.

In Situ Constructing Metal-Organic Complex Interface Layer Using Biomolecule Enabling Stabilize Zn Anode.

Aqueous zinc-ion batteries (ZIBs) are considered as a promising candidate for next-generation large-scale energy storage due to their high safety, low cost, and eco-friendliness. Unfortunately, commercialization of ZIBs is severely hindered owing to rampant dendrite growth and detrimental side reactions on the Zn anode. Herein, inspired by the metal-organic complex interphase strategy, the authors apply adenosine triphosphate (ATP) to in situ construct a multifunctional film on the metal Zn surface (marked as ATP@Zn) by a facile etching method. The ATP-induced interfacial layer enhances lipophilicity, promoting uniform Zn2+ flux and further homogenizing Zn deposition. Meanwhile, the functional interlayer improves the anticorrosion ability of the Zn anode, effectively suppressing corrosion and hydrogen evolution. Consequently, the as-prepared ATP@Zn anode in the symmetric cell exhibits eminent plating/stripping reversibility for over 2800 h at 5.0 mA cm-2 and 1 mAh cm-2. Furthermore, the assembled ATP@Zn||MnO2 full cells are investigated to evaluate practical feasibilities. This work provides an efficient and simple strategy to prepare stabilized Zn anode toward high-performance ZIBs.

Hybrid Interface Chemistry Enabling Mixed Conducting via Ultrafast Microwave Polarization Toward Dendrite-Free Zn Anodes.

Zn metal anodes in aqueous electrolytes suffer from interface issues including uncontrolled dendrite growth and undesired side reactions, resulting in their limited application in terms of short circuits and cell failure. Herein, a hybrid interface chemistry strategy is developed through ultrafast microwave polarization at the skin region of bare Zn. Owing to efficient Joule heating directed by abundant local hot spots at electron valleys, the rapid establishment of a dense interfacial layer can be realized within a minute. Stabilized Zn with suppressed side reactions or surface corrosion is therefore achieved due to the interfacial protection. Importantly, hybrid zincophilic sites involving laterally/vertically interconnected Cu-Zn intermetallic compound and Zn2+-conductive oxide species ensure mixed charge conducting (denoted as CuHL@Zn), featuring uniformly distributed electric field and boosted Zn2+ diffusion kinetics. As a consequence, CuHL@Zn in symmetric cells affords lifespans of 2800 and 3200 h with ultra-low polarization voltages (≈19 and 56 mV) at a plating capacity of 1.0 mAh cm-2 for 1 and 5 mA cm-2, respectively. The CuHL@Zn||MnO2 full cell further exhibits cycling stability with a capacity retention of over 80% for 500 cycles at 2 A g-1.

The Influence of Flame Exposure and Solid Particle Erosion on Tensile Strength of CFRP Substrate with Manufactured Protective Coating.

This paper presents the results of laboratory tests for new materials made of a carbon fibre-reinforced polymer (CFRP) composite with a single-sided protective coating. The protective coatings were made of five different powders-Al2O3, aluminium, quartz sand, crystalline silica and copper-laminated in a single process during curing of the prepreg substrate with an epoxy matrix. The specimens were subjected to flame exposure and solid particle erosion tests, followed by uniaxial tensile tests. A digital image correlation (DIC) system was used to observe the damage location and deformation of the specimens. All coatings subjected to solid particle erosion allowed an increase in tensile failure force ranging from 5% to 31% compared to reference specimens made of purely CFRP. When exposed to flame, only three of the five materials tested, Al2O3, aluminium, quartz sand, could be used to protect the surface, which allowed an increase in tensile failure force of 5.6%.

Polycarbonyl polymer with zincophilic sites as protective coating for highly reversible zinc metal anodes.

The Zn anode of aqueous zinc ion batteries (AZIBs) have suffered from a series of rampant side reactions such as dendrite growth and corrosion, which seriously affect the reversibility and stability of Zn anodes. Herein, a polycarbonyl polymer poly(1,4,5,8-naphthalene tetracarboxylic anhydride anthraquinone) imine (PNAQI) as the protective coating is synthesized through a simple solvothermal method with the raw materials of the equimolar 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA) and 2, 6-aminoanthraquinone (2,6-DAAQ). A series of characterizations such as contact angle measurement and ex-situ XRD analysis confirm that it can effectively prevent some side reactions. Moreover, CO on PNAQI can regulate the uniform distribution of zinc, thereby preventing the occurrence of zinc dendrites. Finally, the PNAQI@Zn//PNAQI@Zn symmetrical cell demonstrates a long cycle life exceeding 1000 h at current density of 1.0 mA cm-2 and a capacity of 1.0 mAh cm-2. The result significantly outperforms the cycling performance of the cell with bare zinc anode. Especially, the full battery of PNAQI@Zn//NH4V4O10 demonstrates an excellent capacity retention and prolonged cycle life (96.9 mAh/g after 1000 cycles at 1.0 A/g) compared to Zn//NH4V4O10. This work provides an effective, simple and low-cost solution for developing high-performance AZIBs.

Bottom Deposition Enables Stable All-Solid-State Batteries with Ultrathin Lithium Metal Anode.

Modern strides in energy storage underscore the significance of all-solid-state batteries (ASSBs) predicated on solid electrolytes and lithium (Li) metal anodes in response to the demand for safer batteries. Nonetheless, ASSBs are often beleaguered by non-uniform Li deposition during cycling, leading to compromised cell performance from internal short circuits and hindered charge transfer. In this study, the concept of "bottom deposition" is introduced to stabilize metal deposition based on the lithiophilic current collector and a protective layer composed of a polymeric binder and carbon black. The bottom deposition, wherein Li plating ensues between the protective layer and the current collector, circumvents internal short circuits and facilitates uniform volumetric changes of Li. The prepared functional binder for the protective layer presents outstanding mechanical robustness and adhesive properties, which can withstand the volume expansion caused by metal growth. Furthermore, its excellent ion transfer properties promote uniform Li bottom deposition even under a current density of 6 mA·cm-2. Also, scanning electron microscopy analysis reveals a consistent plating/stripping morphology of Li after cycling. Consequently, the proposed system exhibits enhanced electrochemical performance when assessed within the ASSB framework, operating under a configuration marked by a high Li utilization rate reliant on an ultrathin Li.

Bipolar Polymeric Protective Layer for Dendrite-Free and Corrosion-Resistant Lithium Metal Anode in Ethylene Carbonate Electrolyte.

The unstable interface between Li metal and ethylene carbonate (EC)-based electrolytes triggers continuous side reactions and uncontrolled dendrite growth, significantly impacting the lifespan of Li metal batteries (LMBs). Herein, a bipolar polymeric protective layer (BPPL) is developed using cyanoethyl (-CH2CH2C≡N) and hydroxyl (-OH) polar groups, aiming to prevent EC-induced corrosion and facilitating rapid, uniform Li+ ion transport. Hydrogen-bonding interactions between -OH and EC facilitates the Li+ desolvation process and effectively traps free EC molecules, thereby eliminating parasitic reactions. Meanwhile, the -CH2CH2C≡N group anchors TFSI- anions through ion-dipole interactions, enhancing Li+ transport and eliminating concentration polarization, ultimately suppressing the growth of Li dendrite. This BPPL enabling Li|Li cell stable cycling over 750 cycles at 10 mA cm-2 for 2 mAh cm-2. The Li|LiNi0.8Mn0.1Co0.1O2 and Li|LiFePO4 full cells display superior electrochemical performance. The BPPL provides a practical strategy to enhanced stability and performance in LMBs application.