Suppress Dendrite Growth Research Articles

Elaborate artificial construction of porous biomass carbon interfacial layer on the surface of zinc anode toward high performance aqueous zinc-ion batteries

Aqueous zinc ion batteries (AZIBs) have emerged as one of the most promising candidates for large-scale energy storage and other fields owing to their low cost, high safety and environmental friendliness. However, the dendritic issue and side reactions induced by the zinc anode-electrolyte interface have always been the major obstacles hindering their development. Herein, porous biomass carbon (BCK) is artificially designed via a simple method to act as an ex-situ surface coating on the zinc anode to resolve the above problems. The interface coating effectively reduces the interface area of direct contact between the zinc anode and electrolyte, thereby suppressing dendrite growth and parasitic reactions. Especially, BCK has a rich pore structure and zincophilic oxygen-containing functional groups, providing sufficient active sites, which can adsorb Zn2+ and preferentially nucleate on the surface of BCK, thus eliminating the tip effect and making the surface of the zinc sheet uniform and flat. In addition, the large specific surface area of BCK can promote the transport and nucleation kinetics of Zn2+, guide the formation of a uniform surface electric field on the zinc anode, enhance the deposition rate of Zn2+ at the anode-electrolyte interface, which helps to guide the uniform nucleation, growth, and deposition of Zn2+. Benefiting from these advantages, the assembled symmetric cells have lower voltage hysteresis and longer cycling performance than bare Zn cells, and the full cell delivers a capacity of 166.5 mAh g−1 and the capacity retention rate of 61.5 % after 1000 cycles at 1 A g−1, which is significantly higher than that of bare Zn assembled full cell.

Temperature-dependent Viscoelastic Liquid MOFs Based Cellulose Gel Electrolyte for Advanced Lithium-Sulfur Batteries Over an Extensive Temperature Range

The uncontrolled growth of lithium dendrites severely limits the practical use of Li-S batteries. Additionally, cell temperature increases during operation, accelerating dendrite growth and side reactions. To stabilize the anode over a wide temperature range, we proposed a promising solution of a novel temperature-dependent viscoelastic liquid UiO66 MOFs-based cellulose gel electrolyte. This specially engineered electrolyte demonstrated superior stabilization of the anode. It adopted the “blocking anions and promoting Li+ transfer” strategy, resulting in a uniform Li+ flux deposition and the formation of a stable and dense solid electrolyte interphase layer, effectively suppressing dendrite growth. To further improve the cycling performance of the cell, a hollow transition bi-metal selenide (FeCo-Se2/NC) was developed as the sulfur host material. This complex exhibited a strong chemisorption capacity for polysulfides and a high catalytic ability to expedite the conversion process of lithium polysulfides. The final cell achieved a high capacity of 687.2 mAh g−1 after 500 cycles at 3 C with a minimal fading rate of 0.04% per cycle. It also demonstrated a high area capacity of 5.78 mAh cm−2 at a high sulfur loading of 6.2 mg cm−2, along with excellent cycling stability under temperature-varying conditions. The findings not only highlighted the commercialization potential of Li-S batteries but also underscored the effectiveness of porous liquid MOFs as a modified layer, effectively stabilizing the Li anode and reducing interfacial impedance between the electrolyte and electrode. Our research paved the way for advanced energy storage solutions that could significantly contribute to a sustainable and eco-friendly future.

Stable sodium-metal batteries with a hierarchical structured electrode toward reversible confinement of Na dendrites

Sodium metal is a promising candidate for the future of rechargeable batteries. However, a significant problem, that is, the growth of sodium dendrites, which are uncontrolled microscopic structures that reduce battery performance and stability, remains unaddressed. To resolve this issue, the development of three-dimensional (3D) nanostructured hosts to prevent dendrite growth and cease the buildup of inactive sodium has been proposed. However, research on developing an uncomplicated process to design these 3D hosts is currently lacking. In this study, we used the ice-templating method to form a self-supporting 3D hierarchical porous structure using a graphene oxide dispersion. This approach offers significant benefits in terms of scalability and cost-effectiveness. The resulting porous design offers numerous nucleation sites, which in turn reduce the intensity of local electric fields around dendrites and lower the current density. Consequently, sodium ions are deposited more evenly, which helps inhibit dendrite growth. Our test results indicated stable cycling performance, with 250, 200, and 150 cycles achieved for deposition volumes of 0.25, 0.5, and 1.0 mAh cm−2, respectively, at a constant current density of 0.25 mA cm−2. By utilizing in situ optical cell analysis, we observed the effective suppression of dendrite growth. Furthermore, ex situ examination confirmed the absence of dendrite formation, even at a high deposition capacity of 5.0 mAh cm−2. These results underline the potential of using a 3D hierarchical porous structure to effectively improve the performance and longevity of sodium-metal batteries.

Sustainable Dual‐Layered Interface for Long‐Lasting Stabilization of Lithium Metal Anodes

AbstractLithium metal anodes (LMAs) offer substantial promise for high‐energy‐density rechargeable batteries, but managing the complex electrolyte–anode interface is a challenge. Herein, a sustainable dual‐layered interface (SDI) protected Li anode is developed using a joint electrospinning‐rolling technique. In this SDI, polyacrylonitrile (PAN) nanofibers normalize Li‐ion flux across the bulk electrolyte and mitigate electrode volume expansion. More significantly, the continuous release of lithiophilic metal ions aids in constructing alloy interphase in situ, which facilitates Li‐ion transport and uniform lithium deposition. With the dynamic protection of SDI films, cracks in the alloy layer can be promptly repaired during cycling, ensuring efficient control of the electrolyte–anode interface and prolonged stabilization of LMAs. As validation, using a PAN/SnCl2 film as an SDI prototype, the symmetric cells achieve ultra‐long cycling of 5200 h (≈7 months) at 5 mA cm−2 and 5 mAh cm−2. When paired with a sulfur cathode (in ether electrolyte) or a LiNi0.8Co0.1Mn0.1O2 cathode (in ester electrolyte), the full cells exhibit exceptional stability and rate performance. This sustainable protection strategy for LMAs opens a path to suppress dendrite growth, creating new opportunities for advanced lithium metal batteries.

Combining Janus Separator and Organic Cathode for Dendrite‐Free and High‐Performance Na‐Organic Batteries

AbstractThe growth of Na‐dendrites and the dissolution of organic cathodes are two major challenges that hinder the development of sodium‐organic batteries (SOBs). Herein, a multifunctional Janus separator (h‐BN@PP@C) by using an interfacial engineering strategy, is proposed to tackle the issues of SOBs. The carbon layer facing the organic cathode serves as a barrier to capture dissolved organic materials and enhance their utilization. Meanwhile, the h‐BN layer facing the Na anode possesses high thermal conductivity and mechanical strength, which mitigates the occurrence of localized‐temperature “hot spots” and promotes the formation of a NaF‐enriched SEI, thereby suppressing dendrite growth. Consequently, the Janus separator enables a stable Na plating/stripping cycling for 1000 h at 3 mA cm−2. Equipped with the Janus separator, organic cathodes including dibenzo[b,i]thianthrene‐5,7,12,14‐tetraone (DTT), pentacene‐5,7,12,14‐tetrone and Calix[4]quinone cathodes demonstrate high capacity and remarkable cycling performance. In particular, the DTT exhibits a bipolar co‐reaction storage mechanism and achieves an ultrahigh capacity (≈342.6 mAh g−1), long‐term cycling stability (capacity decay rate of 0.15% per cycle over 550 cycles at 500 mA g−1) and fast kinetics (1000 mA g−1≈2.8 C). This study offers a straightforward, effective, and promising solution to address the challenges in SOBs.

Anthraquinone-Based Silicate Covalent Organic Frameworks as Solid Electrolyte Interphase for High-Performance Lithium-Metal Batteries.

Lithium (Li)-metal batteries (LMBs) possess the highest theoretical energy density among current battery designs and thus have enormous potential for use in energy storage. However, the development of LMBs has been severely hindered by safety concerns arising from dendrite growth and unstable interphases on the Li anode. Covalent organic frameworks (COFs) incorporating either redox-active or anionic moieties on their backbones have high Li-ion (Li+) conductivities and mechanical/chemical stabilities, so are promising for solid electrolyte interphases (SEIs) in LMBs. Here, we synthesized anthraquinone-based silicate COFs (AQ-Si-COFs) that contained both redox-active and anionic sites via condensation of tetrahydroxyanthraquinone with silicon dioxide. The nine Li+-mediated charge/discharge processes enabled the AQ-Si-COF to demonstrate an ionic conductivity of 9.8 mS cm-1 at room temperature and a single-ion-conductive transference number of 0.92. Computational studies also supported the nine Li+ mechanism. We used AQ-Si-COF as the solid electrolyte interphase on the Li anode. The LMB cells with a LiCoO2 cathode attained a maximum reversible capacity of 188 mAh g-1 at 0.25 C during high-voltage operation. Moreover, this LMB cell demonstrated suppressed dendrite growth and stable cyclability, with its capacity decreasing by less than 3% up to 100 cycles. These findings demonstrate the effectiveness of our redox-active and anionic COFs and their practical utility as SEI in LMB.

Highly Reversible Zn Anodes Achieved by Enhancing Ion-Transport Kinetics and Modulating Zn (002) Deposition.

Uncontrolled dendrite growth and water-related side reactions in mild electrolytes are the main causes of poor cycling stability of zinc anodes, resulting in the deterioration of aqueous zinc-based batteries. Herein, a multifunctional fluorapatite (Ca5(PO4)3F) aerogel (FAG) interface layer is proposed to realize highly stable zinc anodes via the integrated regulation of Zn2+ migration kinetics and Zn (002) orientation deposition. Owing to the well-defined aerogel nanochannels and the rich Zn2+ adsorption sites resulting from the ion exchange between Ca2+ and Zn2+, the FAG interface layer could significantly accelerate the Zn2+ migration and effectively homogenize the Zn2+ flux and nucleation sites, thus promoting rapid and uniform Zn2+ migration at the electrode/electrolyte interface. Additionally, during the cycling process, the F atoms from FAG promote the in situ generation of ZnF2, which facilitates the manipulation of the preferred Zn (002) orientation deposition, thus efficiently suppressing dendrite growth and side reactions by combining with the above synergistic effects. Consequently, the FAG-modified Zn anode displays a stable cycle life of over 4000 h at 1 mA cm-2 and exhibits highly reversible Zn plating/stripping behavior. Meanwhile, the Zn||MnO2 full cells exhibit improved cycle stability over 2000 cycles compared with that of the bare Zn, highlighting the virtues of the FAG protective layer for highly reversible Zn anodes. Our work brings the insight in to stabilize Zn anodes and power the commercial applications of aqueous zinc-based batteries.

Reviving Zn0 Dendrites to Electroactive Zn2+ by Mesoporous MXene with Active Edge Sites.

Zinc metal-based aqueous batteries (ZABs) offer a sustainable, affordable, and safe energy storage alternative to lithium, yet inevitable dendrite formation impedes their wide use, especially under long-term and high-rate cycles. How the battery can survive after dendrite formation remains an open question. Here, we pivot from conventional Zn dendrite growth suppression strategies, introducing proactive dendrite-digesting chemistry via a mesoporous Ti3C2 MXene (MesoTi3C2)-wrapped polypropylene separator. Spectroscopic characterizations and electrochemical evaluation demonstrate that MesoTi3C2, acting as an oxidant, can revive the formed dead Zn0 dendrites into electroactive Zn2+ ions through a spontaneous redox process. Density functional theory reveals that the abundant edge-Ti-O sites in our MesoTi3C2 facilitate high oxidizability and electron transfer from Zn0 dendrites compared to their in-plane counterparts. The resultant asymmetrical cell demonstrates remarkable ultralong cycle life of 2200 h at a practical current of 5 mA cm-2 with a low overpotential (<50 mV). The study reveals the unexpected edge effect of mesoporous MXenes and uncovers a new proactive dendrite-digesting chemistry to survive ZABs, albeit with inevitable dendrite formation.

A LiF-Rich Solid Electrolyte Interphase in a Routine Carbonate Electrolyte by Tuning the Interfacial Chemistry Behavior of LiPF6 for Stable Li Metal Anodes.

Lithium (Li) dendrite growth in a routine carbonate electrolyte (RCE) is the main culprit hindering the practical application of Li metal anodes. Herein, we realize the regulation of the LiPF6 decomposition pathway in RCE containing 1.0 M LiPF6 by introducing a "self-polymerizing" additive, ethyl isothiocyanate (EITC), resulting in a robust LiF-rich solid electrolyte interphase (SEI). The effect of 1 vol % EITC on the electrode/electrolyte interfacial chemistry slows the formation of the byproduct LixPOFy. Such a LiF-rich SEI with EITC polymer winding exhibits a high Young's modulus and a uniform Li-ion flux, which suppresses dendrite growth and interface fluctuation. The EITC-based Li metal cell using a Li4Ti5O12 cathode delivers a capacity retention of 81.4% over 1000 cycles at 10 C, outperforming its counterpart. The cycling stability of 1 Ah pouch cells was further evaluated under EITC. We believe that this work provides a new method for tuning the interfacial chemistry of Li metal through electrolyte additives.

Dual-functional chloropyrazine additives for enhanced performance of lithium-sulfur batteries

The commercialization of lithium-sulfur batteries (LSBs) faces challenges due to uncontrolled lithium deposition and lithium polysulfides (LiPSs) shuttling. In this study, a class of chloropyrazine-based electrolyte additives was introduced to address these issues. The results showed that the presence of chloropyrazine facilitated the formation of a robust and smooth organic-inorganic hybrid solid-electrolyte interface (SEI) enriched with LiCl. This SEI layer enabled reversible lithium plating/stripping, suppressed dendrite growth, and protected the lithium anode from detrimental side reactions with LiPSs. Furthermore, Density functional theory (DFT) results demonstrate that chloropyrazine additives effectively modulated the molecular orbital energy levels of LiPSs and promoted the kinetics of their conversion reactions. LSBs incorporating chloropyrazine additives demonstrated outstanding high-rate performance and long-term cycling stability, with over 800 cycles at 1 C rate and a capacity retention of 81.6 %. Even under challenging conditions of high sulfur loading (5.8 mg cm−2) and low electrolyte-to-sulfur ratio (5 μL mg−1), the battery demonstrated capacity decay rate of only 0.066 % per cycle after 500 cycles at 0.2 C rate. With the highlights of dual-functional chloropyrazine electrolyte additives in improving interfacial chemistry and modulating the orbital energy levels of LiPSs, this work offers a promising direction for advanced electrolyte design in LSBs.

Suppressing Dendrite Growth with Eco-Friendly Sodium Lignosulfonate Additive in Quasi-Solid-State Li Metal Battery.

The application of lithium metal batteries is limited by the drawbacks of safety problems and Li dendrite formation. Quasi-solid-state electrolytes (QSSEs) are the most promising alternatives to commercial liquid electrolytes due to their high safety and great compatibility with electrodes. However, Li dendrite formation and the slow Li+ diffusion in QSSEs severely hinder uniform Li deposition, thus leading to Li dendrite growth and short circuits. Herein, an eco-friendly and low-cost sodium lignosulfonate (LSS)-assisted PVDF-based QSSE is proposed to induce uniform Li deposition and inhibit Li dendrite growth. Li symmetric cells with 5%-LSS QSSE possess a high Li+ transfer number of 0.79, and they exhibit a long cycle life of 1000 h at a current density/areal capacity of 1 mA cm-2/5 mAh cm-2. Moreover, due to the fast electrochemical dynamics endowed by the improved compatibility of the electrodes and fast Li+ diffusion, the LFP/5%-LSS/Li full cells still maintain a high capacity of 110 mAh g-1 after 250 cycles at 6C. This work provides a novel and promising choice that uses eco-friendly LSS as an additive to PVDF-based QSSE in Li metal batteries.

Fine‐Tuning Electrolyte Concentration and Metal–Organic Framework Surface toward Actuating Fast Zn2+ Dehydration for Aqueous Zn‐Ion Batteries

AbstractFunctional porous coating on zinc electrode is emerging as a powerful ionic sieve to suppress dendrite growth and side reactions, thereby improving highly reversible aqueous zinc ion batteries. However, the ultrafast charge rate is limited by the substantial cation transmission strongly associated with dehydration efficiency. Here, we unveil the entire dynamic process of solvated Zn2+ ions’ continuous dehydration from electrolyte across the MOF‐electrolyte interface into channels with the aid of molecular simulations, taking zeolitic imidazolate framework ZIF‐7 as proof‐of‐concept. The moderate concentration of 2 M ZnSO4 electrolyte being advantageous over other concentrations possesses the homogeneous water‐mediated ion pairing distribution, resulting in the lowest dehydration energy, which elucidates the molecular mechanism underlying such concentration adopted by numerous experimental studies. Furthermore, we show that modifying linkers on the ZIF‐7 surface with hydrophilic groups such as −OH or −NH2 can weaken the solvation shell of Zn2+ ions to lower the dehydration free energy by approximately 1 eV, and may improve the electrical conductivity of MOF. These results shed light on the ions delivery mechanism and pave way to achieve long‐term stable zinc anodes at high capacities through atomic‐scale modification of functional porous materials.

Fine-Tuning Electrolyte Concentration and Metal-Organic Framework Surface toward Actuating Fast Zn2+ Dehydration for Aqueous Zn-Ion Batteries.

Functional porous coating on zinc electrode is emerging as a powerful ionic sieve to suppress dendrite growth and side reactions, thereby improving highly reversible aqueous zinc ion batteries. However, the ultrafast charge rate is limited by the substantial cation transmission strongly associated with dehydration efficiency. Here, we unveil the entire dynamic process of solvated Zn2+ ions' continuous dehydration from electrolyte across the MOF-electrolyte interface into channels with the aid of molecular simulations, taking zeolitic imidazolate framework ZIF-7 as proof-of-concept. The moderate concentration of 2 M ZnSO4 electrolyte being advantageous over other concentrations possesses the homogeneous water-mediated ion pairing distribution, resulting in the lowest dehydration energy, which elucidates the molecular mechanism underlying such concentration adopted by numerous experimental studies. Furthermore, we show that modifying linkers on the ZIF-7 surface with hydrophilic groups such as -OH or -NH2 can weaken the solvation shell of Zn2+ ions to lower the dehydration free energy by approximately 1 eV, and may improve the electrical conductivity of MOF. These results shed light on the ions delivery mechanism and pave way to achieve long-term stable zinc anodes at high capacities through atomic-scale modification of functional porous materials.

Strategy for High-Energy Li-S Battery Coupling with a Li Metal Anode and a Sulfurized Polyacrylonitrile Cathode.

Among lithium-sulfur (Li-S) battery materials, sulfurized polyacrylonitrile (SPAN) has attracted substantial attention as a cathode material owing to its potential to bypass the problematic polysulfide formation and shuttling effect. Carbonate-based electrolytes have been eschewed compared with ether-based electrolytes because of their poor compatibility with Li metal anodes. In this work, we design and study an electrolyte comprising 0.8 M of lithium bis(trifluoromethanesulfonyl)imide, 0.2 M of lithium difluoro(oxalate)borate, and 0.05 M of lithium hexafluorophosphate in ethyl methyl carbonate/fluoroethylene carbonate = 3:1 v/v solution in the Li-S battery coupled with a Li metal anode and SPAN cathode. The well-designed carbonate-based electrolyte effectively stabilizes both electrodes, delivering high Coulombic efficiencies with stable cyclability. Studies using operando optical microscopy and atomic force microscopy demonstrate that dense, uniform Li deposition is promoted to suppress dendrite growth even at a high current density. Operando Raman spectroscopy reveals a reversible Li+ storage behavior in the SPAN structure through the cleavage of disulfide bonds and their redimerization during lithiation and delithiation. As a result, the proposed Li-S battery delivers an overall capacity retention of 73.5% over 1000 cycles, with high Coulombic efficiencies over 99.9%.

Regulating interfacial reaction through electrolyte chemistry enables gradient interphase for low-temperature zinc metal batteries

In situ formation of a stable interphase layer on zinc surface is an effective solution to suppress dendrite growth. However, the fast transport of bivalent Zn-ions within the solid interlayer remains very challenging. Herein, we engineer the SEI components and enable superior kinetics of Zn metal batteries under harsh conditions through regulating the sequence of interfacial chemical reaction. With the differences in chemical reactivity of trimethyl phosphate co-solvent and trifluoromethanesulfonate anions in the Zn2+-solvation shell, Zn3(PO4)2 and ZnF2 are successively generated on Zn metal surface to form a gradient ZnF2–Zn3(PO4)2 interphase. Mechanistic studies reveal the outer ZnF2 facilitates Zn2+ desolvation and inner Zn3(PO4)2 serves as channels for fast Zn2+ transport, contributing to long-term cycling at subzero temperatures. Impressively, the gradient SEI enables a high lifespan over 7000 hours in Zn symmetric cell and a capacity retention of 86.1% after 12000 cycles in Zn–KVOH full cell at –50 °C.

Dendrite Growth Suppression and in-Situ Surface Observation of Lithium Battery Under an Optical Microscope

Dendrite growth is a major obstacle to the commercialization of lithium metal batteries. A dendrite formed on a Li anode can cause thermal run-aways and permanent capacity loss. Despite previous research efforts, the behavior of lithium dendrite growth is elusive since it is related to multiple factors. An in-situ optical techniques is considered as one of the major methods to study the dendrites growth behaviors and morphologies real-time.A better knowledge of the physico-chemical processes and the side reactions during a battery operation can be gained.A home-designed in-situ optical cell with a digital optical microscope was used to investigate the behavior of Li deposition on a metallic Li electrode under different electrochemical operation conditions. The impacts of electrolytes, additives and cycling conditions on the dendrite formation were investigated. The changes of the morphology and the shape of the dendrites were investigated correspondingly. Guiding by the in-situ optical observation results, polycyclic aromatic hydrocarbons (PAHs) were introduced as additives to suppress the dendrite growth. It was observed in an in-situ optical experiment, that the freshly formed dendrites can be dissolved and dispersed throughout the surface, eventually a dynamic elastic protection layer was formed. With the liquid electrolyte trapped in the protection layer, the thickness of the layer could be self-adjusted to compensate for the volume change of the Li anode during the battery cycling. Among the eight additives added to the electrolyte, several PAH additives have significant effect on suppressing dendrite growth and greatly enhance the cyclability of the Lithium electrode in a symmetry Li/Li cell. Tarascon, J.-M., & Armand, M. (2001). Issues and challenges facing rechargeable lithium batteries. Nature, 414(6861), 359–367.Tripathi, A. M., Su, W.-N., & Hwang, B. J. (2018). In situ analytical techniques for battery interface analysis. Chemical Society Reviews, 47(3), 736–851. Figure 1

Nanospinbar-Assisted Convective Ionic Transfer Toward Dendrite-Free Li Metal Batteries

Building high-energy-density batteries with Li-metal anodes (LMAs) featuring ultrahigh specific capacity (3860 mAh g−1) and low working voltage (−3.04 V vs. SHE) have been revisited to surpass the energy density limit of current Li-ion batteries. For instance, a successful transition from conventional graphite (372 mAh g–1) to ultrathin LMAs can deliver higher cell energies (over 500 Wh kg–1). Nonetheless, Li electrodeposition is challenging due to the dendrite formation and random growth. Extensive Li dendrite growth can enlarge the active surface area where side reactions occur, thereby severely deteriorating the Li surface and depleting the electrolyte, leading to poor cycling stability. Eventually, the Li dendrite tips can pierce the separator, causing cell short-circuiting, thereby increasing the safety risk. This is a major hurdle that must be overcome prior to commercialization. Therefore, inhibiting uneven dendritic Li plating is essential for safe and stable cycling of rechargeable lithium metal batteries (LMBs).Inhibiting uneven, dendritic Li electroplating is crucial for the safe and stable cycling of LMBs. Homogeneous, fast Li+ transport toward the Li surface is required for uniform, dendrite-free deposition. Electrodeposition strongly depends on the mass transfer of the ionic species. In a diffusion-limited regime, such as higher currents and lack of convection, inherently limited Li+ diffusion causes a strong concentration gradient or even total Li+ depletion. Moreover, traditional ionic transport of static liquid electrolytes involving electromigration and molecular diffusion can trigger a greater disparity in Li concentration over the Li surface, leading to irregular dendrite growth.This study presents a microturbulence-assisted convective Li+ transfer for suppressing dendrite growth using a magnetic nanospinbar (NSB)-dispersed colloidal electrolyte. We synthesized an ultrahigh-aspect-ratio NSB consisting of a paramagnetic Fe3O4 nanoparticle array and a silica outer coating. Manipulating the external electromagnetic force can remotely control the rotation of individual NSBs without dispersion failure, thereby generating a microturbulence flow inside the cell. Regardless of the electrolyte composition, rotating the NSB can reduce the Li+ diffusion layer thickness from the bulk and evenly redistribute Li+ flux over the Li surface, thereby suppressing Li dendrite growth. The NSB-dispersed electrolyte with advanced salt/solvent compositions demonstrated stable cycling of LMBs over 600 cycles at 70% capacity retention, thereby outperforming the NSB-free cell.Figure. 1. Concept of convective Li+ transfer assisted by remote NSB stirring. Apart from stagnant electrolytes, magnetic-field-responsive NSB dispersed in the liquid electrolyte can redistribute Li+ flux near LMA through remote stirring, enabling facile, homogenous Li+ transfer and thereby leading to uniform, dendrite-free Li electroplating Figure 1

Surface-Engineered Zn-Based Alloys Anodes for Aqueous Zn Batteries

Safety and durability concerns caused by surface and interface instabilities of high-surface-activity energy materials are challenging modern electrochemical energy conversion and storage systems. In this presentation, I will present our most recent representative works on the surface engineering of functional materials for aqueous batteries. In this work, we designed an in-situ visualized protocol that can exactly mimic the actual electrochemical environments used in aqueous batteries. Using this novel protocol, we observed the dynamic processes of metal plating/stripping on the alloys in aqueous batteries. Comprehensive and systematic studies based on experimental, theoretical, spectroscopic, and microscopic approaches prove that absolute reversibility can be achieved by using the proposed 3D alloys because of the significantly improved Zn diffusion and successfully suppressed dendrite growth. As a proof-of-concept, the novel alloy structures deliver unprecedented stability with nearly 100% Coulombic efficiency over thousands of cycles even under harsh electrochemical conditions, including testing in seawater-based aqueous electrolytes and using a high current density of 80 mA cm-2.

Triple-function Hydrated Eutectic Electrolyte for Enhanced Aqueous Zinc Batteries.

Aqueous rechargeable zinc-ion batteries (ARZBs) are impeded by the mutual problems of unstable cathode, electrolyte parasitic reactions, and dendritic growth of zinc (Zn) anode. Herein, a triple-functional strategy by introducing the tetramethylene sulfone (TMS) to form a hydrated eutectic electrolyte is reported to ameliorate these issues. The activity of H2O is inhabited by reconstructing hydrogen bonds due to the strong interaction of TMS and H2O. Meanwhile, the preferentially adsorbed TMS on the Zn surface increases the thickness of double electric layer (EDL) structure, which provides a shielding buffer layer to suppress dendrite growth. Interestingly, TMS modulates the primary solvation shell of Zn2+-6H2O ultimately to achieve a novel solvent co-intercalation ((Zn-TMS)2+) mechanism, and the intercalated TMS works as a "pillar" that provides more zincophilic sites and stabilize the structure of cathode (NH4V4O10, (NVO)). Consequently, the Zn||NVO battery exhibits a remarkable high specific capacity of 515.6 mAh g-1 at a low current density of 0.2 A g-1 for over 40 days. This multi-functional electrolytes and solvent co-intercalation mechanism will significantly propel the practical development of aqueous batteries.

Triple‐function Hydrated Eutectic Electrolyte for Enhanced Aqueous Zinc Batteries

AbstractAqueous rechargeable zinc‐ion batteries (ARZBs) are impeded by the mutual problems of unstable cathode, electrolyte parasitic reactions, and dendritic growth of zinc (Zn) anode. Herein, a triple‐functional strategy by introducing the tetramethylene sulfone (TMS) to form a hydrated eutectic electrolyte is reported to ameliorate these issues. The activity of H2O is inhibited by reconstructing hydrogen bonds due to the strong interaction between TMS and H2O. Meanwhile, the preferentially adsorbed TMS on the Zn surface increases the thickness of double electric layer (EDL) structure, which provides a shielding buffer layer to suppress dendrite growth. Interestingly, TMS modulates the primary solvation shell of Zn2+ ultimately to achieve a novel solvent co‐intercalation ((Zn‐TMS)2+) mechanism, and the intercalated TMS works as a “pillar” that provides more zincophilic sites and stabilizes the structure of cathode (NH4V4O10, (NVO)). Consequently, the Zn||NVO battery exhibits a remarkably high specific capacity of 515.6 mAh g−1 at a low current density of 0.2 A g−1 for over 40 days. This multi‐functional electrolytes and solvent co‐intercalation mechanism will significantly propel the practical development of aqueous batteries.