SEI Layer Research Articles

Constructing a Multifunctional SEI Layer Enhancing Kinetics and Stabilizing Zinc Metal Anode

AbstractZn dendrite growth and parasitic reactions at the interface of zinc anode/electrolyte in aqueous zinc batteries severely hinder its lifespan in application. Herein, the zinc anode is effectively stabilized by introducing trace amounts of 4‐aminobutane‐1‐phosphate (ABPA) into the ZnSO4 electrolyte. The ABPA adsorbs onto the surface of zinc anode and then further decomposes to a high conductive organic/inorganic composite in situ SEI layer including amino, partial carbon chain, and zinc phosphate. In the SEI layer, the residual undecomposed carbon chain promotes the desolvation of Zn2+, the amino induces uniform Zn2+ plating and zinc phosphate facilitates the migration of Zn2+. Thus, this in situ SEI layer not only suppresses water‐related side reactions but also enhances the Zn2+ transport kinetics. As a result, Zn||Zn symmetric cell delivers an ultralong cycle life of over 13 000 cycles at 50 mA cm−2 and 1 mAh cm−2. A high average Coulombic efficiency of 99.72% is achieved in over 1000 cycles in Zn||Cu half‐cell. The Zn||I2 full cell delivers a high‐capacity retention of 91.42% after 40,000 cycles. Moreover, a 49 mAh Zn||I2 pouch cell maintains 80.28% capacity retention over 300 cycles and 61.22% after 1000 cycles.

Internal Electron-Donation Allocation Design for Intrinsic Solubilization of Lithium Nitrate in Ester Electrolyte for Stable Lithium Metal Batteries.

Lithium metal batteries (LMBs) have become a hot topic in the research of next-generation advanced battery technology due to their high specific energy. However, the high reaction activity between lithium metal and electrolyte is considered one of the key bottlenecks limiting large-scale applications of LMBs. As a classic electrolyte additive, LiNO3 significantly improves the stability of lithium metal in ether-based electrolytes. However, its solubility in carbonate-based electrolytes widely used in lithium-ion batteries is extremely low, and its protective effect on lithium metal is limited, which has become a key obstacle to the commercial application of lithium metal batteries. Here, we enhanced the local negative charge density of carbonyl oxygen atoms in carbonate molecules by introducing electron donors, making it easier for them to coordinate with Li+, thereby weakening the interaction between Li+ and NO3-, and significantly increasing the solubility of LiNO3 in ester electrolytes. The modified ester solvent promotes the derivatization and decomposition of salt anions, leading to the formation of a dense SEI layer rich in LiF and LiNxOy. This significantly improves the stability of lithium metal in ester-based electrolytes. The assembled Li||Li symmetric battery shows excellent cycling performance of over 4000 hours.

Cross-linking γ-Polyglutamic Acid as a Multifunctional Binder for High-Performance SiOx Anode in Lithium-Ion Batteries.

SiOx is a highly promising anode material for realizing high-capacity lithium-ion batteries owing to its high theoretical capacity. However, the large volume change during cycling limits its practical application. The development of a binder has been demonstrated as one of the most economical and efficient strategies for enhancing the SiOx anode's electrochemical performance. In this work, a multifunctional binder (T-PGA) is fabricated by cross-linking γ-polyglutamic acid (PGA) and tannic acid (TA) for SiOx anodes. The introduction of TA into PGA helps to buffer the volume changes of the SiOx anodes, facilitate diffusion of Li+, and construct stable SEI layers. Benefiting from this proposed binder, the SiOx anode maintains a reversible capacity of 973.0 mAh g-1 after 500 cycles at 500 mA g-1 and the full cell, pairing with LiNi0.5Co0.2Mn0.3O2 cathode, delivers a reversible capacity of 133 mA h g-1 (73.2% retention) after 100 cycles. This study offers valuable insights into advanced binders that are used in high-performance Li-ion batteries.

Potential-Dependent ATR-SEIRAS and EQCM-D Analysis of Interphase Formation in Zinc Battery Electrolytes.

With the heightening interest in bivalent battery technology, there arises a necessity for a thorough investigation into zinc-ion battery (ZIB) electrolytes, accommodating their chemical attributes and potential-dependent structural dynamics. While the phenomenon of in situ solid electrolyte interphase formation is extensively documented in lithium-ion batteries, its analogous occurrences in ZIBs remain limited. Herein is a comparative study of three zinc electrolytes of interest: ZnSO4, ZnOTF, and Zn(TFSI)2/LiTFSI hybrid water-in-salt electrolyte. Additionally, the impact of an acetonitrile additive is scrutinized, with a comparative assessment of the interfacial behavior in aqueous solutions. Utilizing ATR-SEIRAS, potential-dependent alterations in the composition of the electrolyte/electrode interface were monitored, while EQCM-D facilitated a comprehensive understanding of variations in the mass and structural properties of the adsorbed layer. Aqueous ZnSO4 demonstrated the accumulation of porous Zn4SO4(OH)6·xH2O at negative potentials, leading to a mass of 1.47 μg cm-2 after five cycles. Bisulfate formation was observed at positive potentials. SEIRAS measurements for ZnOTF demonstrated reorientation and surface adsorption of CF3SO3- to favor CF3 at the surface for positive potentials, and acetonitrile showed increased stability for the electrode at negative potentials. The additive was also reported to lead to the accumulation of a substantial passivation layer with viscoelastic properties. The zinc water-in-salt showed exceptional surface stability at negative potentials and a widened potential window. A thin rigid zinc SEI layer is reported with a mass of 0.7 μg cm-2. The compositional intricacies of these surface structures are discussed in relation to their solvent conditions. This investigation not only sheds light on the initial charge/discharge cycles in ZIBs but also underscores their pivotal role in instigating enduring transformations that can significantly influence their long-term cycling performance.

Predictive modeling of lithium-ion battery degradation: Incorporating SEI layer growth and mechanical stress factors

Predictive modeling of lithium-ion battery degradation: Incorporating SEI layer growth and mechanical stress factors

Nano ZnO modified amorphous carbon materials enabling long-cycle performance and high-capacity for lithium/sodium-ion batteries

Zinc-modified carbon materials exhibit high specific capacity, good safety, and low self-discharge, making them promising anode materials for lithium-ion and sodium-ion batteries. However, the high cost of raw materials, complex fabrication processes, and limited cycle life remain significant challenges to their further development. In this study, we elucidated a two-step process, simple in technique and suitable for large-scale production, for in-situ zinc modification of amorphous carbon. The synthesized carbon material exhibited superior reversible specific capacity (maintaining 780.27 mAh·g−1 capacity after 80 cycles at 50 mA·g−1 current density), high cycling stability (maintaining Coulombic efficiency at 100.06 % after 15,000 cycles at 10 A·g−1 current density), and good application value (achieving a capacity of 89.67 mAh·g−1 after 1000 cycles at 200 mA·g−1 current density for the assembled MFAC-Zn||NVP full cell). Through our investigation, we discovered that Nano ZnO not only directly participate in electrochemical reactions but also effectively improve the microstructure of amorphous carbon, increasing its three-dimensional axial stacking and providing more reaction sites. The enrichment of open pores significantly enhances the diffusion efficiency of ions within the carbon-based matrix. The superior diffusion ability of alkali metal-ion in the electrode is the reason for the excellent electrochemical performance of Zinc-modified amorphous carbon. Moreover, the incorporation of Nano ZnO aids in the formation of a robust and thin SEI layer. This significantly enhances the stability of the electrode materials during cycling and improves charge transfer efficiency during the charge-discharge process. Our study provides a new strategy for adjusting the internal microstructure of amorphous carbon materials to achieve high-performance lithium/sodium storage.

The Impact of Supersaturated Electrode on Heterogeneous Lithium Nucleation and Growth Dynamics.

The concept of a lithiophilic electrode proves inadequate in describing carbon-based electrode materials due to their substantial mismatch in surface energy with lithium metal. However, their notable capacity for lithium chemisorption can increase active lithium concentration required for nucleation and growth, thereby enhancing the electrochemical performance of lithium metal anodes (LMAs). In this study, we elucidate the effects of the supersaturated electrode which has high active lithium capacity around equilibrium lithium potential on LMAs through an in-depth electrochemical comparison using two distinct carbon electrode platforms with differing carbon structures but similar two-dimensional morphologies. In the supersaturated electrode, both the dynamics and thermodynamic states involved in lithium nucleation and growth mechanisms are significantly improved, particularly under continuous current supply conditions. Furthermore, the chemical structures of the solid-electrolyte-interface layers (SEIs) are greatly influenced by the elevated surface lithium concentration environment, resulting in the formation of more conductive lithium-rich SEI layers. The improved dynamics and thermodynamics of surface lithium, coupled with the formation of enhanced SEI layers, contribute to higher power capabilities, enhanced Coulombic efficiencies, and improved cycling performances of LMAs. These results provide new insight into understanding the enhancements in heterogeneous lithium nucleation and growth kinetics on the supersaturated electrode.

The Impact of Supersaturated Electrode on Heterogeneous Lithium Nucleation and Growth Dynamics

AbstractThe concept of a lithiophilic electrode proves inadequate in describing carbon‐based electrode materials due to their substantial mismatch in surface energy with lithium metal. However, their notable capacity for lithium chemisorption can increase active lithium concentration required for nucleation and growth, thereby enhancing the electrochemical performance of lithium metal anodes (LMAs). In this study, we elucidate the effects of the supersaturated electrode which has high active lithium capacity around equilibrium lithium potential on LMAs through an in‐depth electrochemical comparison using two distinct carbon electrode platforms with differing carbon structures but similar two‐dimensional morphologies. In the supersaturated electrode, both the dynamics and thermodynamic states involved in lithium nucleation and growth mechanisms are significantly improved, particularly under continuous current supply conditions. Furthermore, the chemical structures of the solid‐electrolyte‐interface layers (SEIs) are greatly influenced by the elevated surface lithium concentration environment, resulting in the formation of more conductive lithium‐rich SEI layers. The improved dynamics and thermodynamics of surface lithium, coupled with the formation of enhanced SEI layers, contribute to higher power capabilities, enhanced Coulombic efficiencies, and improved cycling performances of LMAs. These results provide new insight into understanding the enhancements in heterogeneous lithium nucleation and growth kinetics on the supersaturated electrode.

Cyclosulfate additive inhibits Li dendrite disorder growth to achieve stable cycles of Li metal battery

ABSTRACT The high reactivity of lithium metal leads to the uncontrolled growth of lithium dendrites during the charging and discharging process of lithium metal batteries, which results in the poor cycle performance of batteries. In this paper, we innovatively utilized 1, 3-propanediol cyclic sulfate (PCS) as an additive to successfully construct a smooth and dense SEI layer containing sulfur element on the lithium metal anode surface. Under the action of PCS, the cells show excellent performance. After 200 cycles, cells with baseline electrolyte (BE) + 1 wt.% PCS still has a high capacity of of 148mAh g−1 and 81.38% capacity retention compared with cells with BE. In-situ optical microscopy is pioneeringly applied to showcase the generation and growth of lithium dendrites which showed that PCS participated in the formation of the SEI layer, indicating that this optimized SEI layer has better conductivity of Li+ and chemical stability, thus inhibiting malignant lithium deposition and electrolyte decomposition above the lithium metal anode.

Cationic Covalent Organic Framework-Modified Polypropylene Separator for High-Performance Lithium Metal Batteries.

As an important component of lithium batteries, the wettability and thermal stability of the separator play a significant role in cell performance. Despite the availability of numerous commercial separators, issues such as low ion selectivity and poor thermal stability continue to limit the efficiency and reliability of the batteries. Herein, two cationic covalent organic frameworks (Br-COF and TFSI-COF) with abundant imidazole cationic groups were designed to modify commercial polypropylene (PP) separators. The strong lithium-ion affinity of the cationic COF enables the effective dissociation of lithium salt ion clusters, simplifying the solvent structure of lithium ions to promote lithium ions transport. Additionally, solvent anions can be anchored to the cationic COF by electrostatic interactions, reducing side reactions on the lithium metal anode surface to form a favorable SEI layer, which can effectively inhibit the growth of lithium dendrites. The rapid dissociation of anions in lithium salts with some organic solvents and cationic COFs was revealed by a molecular dynamics simulation. A LiF-rich SEI layer on the lithium metal anode surface was formed, which can speed up Li+ transport at interfaces, leading to consistent lithium deposition and outstanding battery performance. The ordered porous structure of the cationic COF provides interconnected and continuous channels, improving the wettability between the liquid electrolyte and separators, which is conducive to ion transport. When paired with a LiFePO4 cathode and electrolyte (1.0 M LiTFSI in DEC: EC: DMC = 1:1:1), the LiFePO4/TFSI-COF@PP/Li cell demonstrates a prominent cycling capacity of 148.0 mAh g-1 at 0.5 C with a Coulombic efficiency of 98.0% in the first cycle, and the capacity retention is 82.0% after 100 cycles, showing good cycling stability. Thus, this investigation provides inspiration for the expansion of cationic COF-modified separators for next-generation lithium metal batteries.

Boosting Fast Charging of Lithium-Metal Batteries via Weak Interactions Between Non-Solvating Solvents and Anions in High-Safety Eutectic Electrolytes.

Proper design of the solvation structure is crucial for the development of lithium metal batteries (LMBs). In this paper, the use of 1,2-Dimethoxyethane (DME) as a non-solvating cosolvent in amide-based eutectic electrolytes is proposed to address challenges related to high viscosity, high polarization, and low conductivity, thus enhancing the compatibility with lithium metal anodes. Through physical characterization combined with simulation calculations the existence of a weak interaction between DME and anions is confirmed, which promotes the dissociation of lithium salts and increases the Li+ transference number and diffusion coefficient, thus improving the fast charging performance of eutectic electrolytes. In addition, stable SEI layer enriched with inorganic components is formed during the cycling process, resulting in uniform and dense lithium deposition. The fast charging performance of the cell can be effectively improved by utilizing the interaction between anions and solvents. The LiFePO4 (LFP)||Li cell has a capacity retention of 97% after 1200 cycles at 5 C and also performs well at high temperature of 50°C. Overall, the use of a non-solvating cosolvent in eutectic electrolytes presents a promising and innovative approach for enhancing electrolyte performance in LMBs.

Sustainable full-cell NCM||Graphite system with superior stability: The hybrid impact of sulfone-containing and flame-retardant additives on interface formation and cyclability

S-containing additives improve the performance, lifetime, and sustainability of lithium-ion batteries (LIBs) through the stabilization of electrode-electrolyte interfaces, modification of electrolyte properties, and facilitating the efficient resource utilization and rapid Li+ migration. Non-etheless, fire safety, extended shelf life, and capacity maintenance are critical concerns for commercial LIBs. Herein, a S-containing film-forming additive, including 4,4-diaminodiphenylsolfon (DADP) by incorporating flame retardancy of dimethyl methyl phosphonate (DMMP) was considered toward taking the barriers of above-mentioned challenges. Based on the calculation, the additives decompose sequentially to produce a distinct SEI via a narrower energy gap under both cathodic and anodic conditions. The NCM532||Graphite with DADP/DMMP showed the enhanced preservation and stability of structure, defined by XRD, Rietveld refinement pattern, SEM, and FT-IR. While the DMMP decreased the fire risk and lowered the capacity due to side reactions, the DADP improved the capacity loss, where the retention rate was 94.91%, 92.01%, 81.29%, and 76.22% within 100, 200, 300, and 400 cycles, respectively. The additive also maintained a capacity of 1123.115 mAhg−1 for 650 cycles, demonstrating excellent cyclability. Therefore, DADP/DMMP facilitate the formation of stable SEI layer, reduce fire risk, improve cycle stability, and offer an achievable path to develop the safe and long-lasting commercial batteries.

High-Entropy-Inspired Multicomponent Electrical Double Layer Structure Design for Stable Zinc Metal Anodes.

Regulating the electrical double layer (EDL) structure can enhance the cycling stability of Zn metal anodes, however, the effectiveness of this strategy is significantly limited by individual additives. Inspired by the high-entropy (HE) concept, we developed a multicomponent (MC) EDL structure composed of La3+, Cl-, and BBI anions by adding dibenzenesulfonimide (BBI) and LaCl3 additives into ZnSO4 electrolytes (BBI/LaCl3/ZnSO4). Specifically, La3+ ions accumulate within EDL to shield the net charges on the Zn surface, allowing more BBI anions and Cl- ions to enter this region. Consequently, this unique MC EDL enables Zn anodes to simultaneously achieve uniform electric field, robust SEI layer, and balanced reaction kinetics. Moreover, the synergistic parameter - a novel descriptor for quantifying collaborative improvement - was first proposed to demonstrates the synergistic effect between BBI and LaCl3 additives. Benefitting from these advantages, Zn metal anodes achieved a high reversibility of 99.5 % at a depth of discharge (DoD) of 51.3 %, and Zn|MnO2 pouch cells exhibited a stable cycle life of 100 cycles at a low N/P ratio of 2.9.

High‐Entropy‐Inspired Multicomponent Electrical Double Layer Structure Design for Stable Zinc Metal Anodes

AbstractRegulating the electrical double layer (EDL) structure can enhance the cycling stability of Zn metal anodes, however, the effectiveness of this strategy is significantly limited by individual additives. Inspired by the high‐entropy (HE) concept, we developed a multicomponent (MC) EDL structure composed of La3+, Cl−, and BBI anions by adding dibenzenesulfonimide (BBI) and LaCl3 additives into ZnSO4 electrolytes (BBI/LaCl3/ZnSO4). Specifically, La3+ ions accumulate within EDL to shield the net charges on the Zn surface, allowing more BBI anions and Cl− ions to enter this region. Consequently, this unique MC EDL enables Zn anodes to simultaneously achieve uniform electric field, robust SEI layer, and balanced reaction kinetics. Moreover, the synergistic parameter – a novel descriptor for quantifying collaborative improvement – was first proposed to demonstrates the synergistic effect between BBI and LaCl3 additives. Benefitting from these advantages, Zn metal anodes achieved a high reversibility of 99.5 % at a depth of discharge (DoD) of 51.3 %, and Zn|MnO2 pouch cells exhibited a stable cycle life of 100 cycles at a low N/P ratio of 2.9.

Study on an Interpenetrating Artificial SEI for Lithium Metal Anode Modification and Fast Charging Characterization.

Artificial SEI is one of the effective strategies to improve lithium dendrites and suppress side reactions. However, the role of SEI components and distribution on the modification of the lithium metal anode remains unclear. Therefore, in this study, the oxygen-sulfur (O-S) component and its distribution in SEI were modulated by designing experiments, and then the mechanism of its action was deeply investigated. The study is based on an in-depth analysis of the properties of lithium sulfide (Li2S) and lithium oxide (Li2O) as SEI layer materials and effectively combines them in an ether electrolyte environment to form an innovative SEI structure. The experimental results show that the optimal SEI modulation condition is O120-S10. O120-S10 significantly improves the kinetic performance of electrochemical reactions, reduces the film resistance, and achieves cycling stability of up to 2100 h during high-capacity lithium deposition/stripping at 5 mAh cm-2. When used in conjunction with a ternary cathode material (NCM811), the O120-S10 demonstrates excellent performance under high rate charge/discharge conditions at 10C. After 1500 cycle tests, the battery's specific capacity was maintained at 90 mAh g-1 and the Coulombic efficiency reached 98.52%. Through X-ray photoelectron spectroscopy (XPS) analysis, the vertical structure and ratio distribution of components in SEI were revealed in detail, and the optimal component ratios of Li2S 46.48%, Li2O 46.02%, and Li2CO3 7.50% were determined. The mechanism of action is to achieve a 1 + 1 > 2 superlinear synergistic effect and fast charging performance by combining the ability of Li2O's low lithium ion diffusion barrier with Li2S's ability to inhibit the growth of lithium dendrites.

Quantifying the Aging of Lithium-Ion Pouch Cells Using Pressure Sensors

Understanding the behavior of pressure increases in lithium-ion (Li-ion) cells is essential for prolonging the lifespan of Li-ion battery cells and minimizing the safety risks associated with cell aging. This work investigates the effects of C-rates and temperature on pressure behavior in commercial lithium cobalt oxide (LCO)/graphite pouch cells. The battery is volumetrically constrained, and the mechanical pressure response is measured using a force gauge as the battery is cycled. The effect of the C-rate (1C, 2C, and 3C) and ambient temperature (10 °C, 25 °C, and 40 °C) on the increase in battery pressure is investigated. By analyzing the change in the minimum, maximum, and pressure difference per cycle, we identify and discuss the effects of different factors (i.e., SEI layer damage, electrolyte decomposition, lithium plating) on the pressure behavior. Operating at high C-rates or low temperatures rapidly increases the residual pressure as the battery is cycled. The results suggest that lithium plating is predominantly responsible for battery expansion and pressure increase during the cycle aging of Li-ion cells rather than electrolyte decomposition. Electrochemical impedance spectroscopy (EIS) measurements can support our conclusions. Postmortem analysis of the aged cells was performed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) to confirm the occurrence of lithium plating and film growth on the anodes of the aged cells. This study demonstrates that pressure measurements can provide insights into the aging mechanisms of Li-ion batteries and can be used as a reliable predictor of battery degradation.

An Evaluation Modeling Study of Thermal Runaway in Li-Ion Batteries Based on Operation Environments in an Energy Storage System

According to the green growth and carbon-neutral policy in Korea, the installation of large-capacity ESSs is rapidly being increased, but a total number of 50 ESS fire cases have occurred since the end of 2023. ESSs are typically composed of series-parallel connections with numerous Li-ion batteries, and when the temperature of a deteriorated cell increases due to thermal, electrical, and mechanical stress, thermal runaway can occur due to additional heat generated by an internal chemical reaction. Here, an internal chemical reaction in a Li-ion battery results in the different characteristics on the decomposition reaction and heat release depending on the operation conditions in the ESS, such as the rising temperature rate, convective heat transfer coefficient, and C-rate of charging and discharging. Therefore, this paper presents mathematical equations and modeling of thermal runaway, composed of the heating device section, heat release section by chemical reaction, chemical reaction section at the SEI layer, chemical reaction section between the negative and positive electrodes and solvents, and chemical reaction section at the electrolyte by itself, based on MATLAB/SIMULINK (2022), which were validated by a thermal runaway test device. From the simulation and test results based on the proposed simulation modeling and test device according to the operation conditions in ESSs, it was found that the proposed modeling is an effective and reliable tool to evaluate the processing characteristics of thermal runaway because the occurrence time intervals and maximum temperatures had almost the same values in both the test device and simulation modeling. Accordingly, it was confirmed that the rising temperature rate and the convective heat transfer coefficient were more critical in the thermal runaway than the C-rate of charging and discharging.

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 (20mgcm-2) or LiNi0.8Co0.1Mn0.1O2 (NCM, 16mgcm-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.

Panthenol Additives with Multiple Coordination Sites Induce Uniform Zinc Deposition and Inhibited Side Reactions for High Performance Aqueous Zinc Metal Battery.

Application of aqueous zinc metal batteries (AZMBs) in large-scale new energy systems (NESs) is challenging owing to the growth of dendrites and frequent side reactions. Here, this study proposes the use of Panthenol (PB) as an electrolyte additive in AZMBs to achieve highly reversible zinc plating/stripping processes and suppressed side reactions. The PB structure is rich in polar groups, which led to the formation of a strong hydrogen bonding network of PB-H2O, while the PB molecule also builds a multi-coordination solvated structure, which inhibits water activity and reduces side reactions. Simultaneously, PB and OTF- decomposition, in situ formation of SEI layer with stable organic-inorganic hybrid ZnF2-ZnS interphase on Zn anode electrode, can inhibit water penetration into Zn and homogenize the Zn2+ plating. The effect of the thickness of the SEI layer on the deposition of Zn ions in the battery is also investigated. Hence, this comprehensive regulation strategy contributes to a long cycle life of 2300h for Zn//Zn cells assembled with electrolytes containing PB additives. And the assembled Zn//NH4V4O10 pouch cells with homemade modules exhibit stable cycling performance and high capacity retention. Therefore, the proposed electrolyte modification strategy provides new ideas for AZMBs and other metal batteries.

Ultra-high areal capacity, ultra-long life, dendrite-free sodium metal anode enabled by antimony-based Na-ion conducting artificial SEI layers

Sodium metal (Na) is a promising anode material for Na metal batteries and solid-state sodium batteries, because of its high theoretical capacity, favorable electrochemical potential, and cost effectiveness. Nevertheless, practical applications of sodium metal anode are hindered by uncontrolled dendrite growth owing to chemical instability of the heterogeneous solid electrolyte interphase layer. In this work, we proposed a simple interface modification strategy employing several antimony-based Na-ion conducting solid electrolyte complexes as protective artificial SEI layer over Na metal. The Na-ion conducting interphases are robust and highly Na-ion conductive to attain uniform sodium ion flux with a small overpotential. Importantly, Na anode with antimony sulfide based solid electrolyte SEI layers exhibited the high-rate performance (10 mA cm−2) along with a remarkable capacity of 30 mAh cm−2, and life span of ∼ 1100 h. We observe that replacing the conventional artificial SEI layers, employing alloy type interface with Na-ion conducting solid electrolyte as artificial SEI components will improve the mechanical robustness at high current and high-capacity conditions. The sodium metal batteries employing modified metal anodes and high voltage Na1.2Mn0.8O1.5F0.5 cathode, exhibited excellent stability and high efficiency at 1C rate. Furthermore, the modified metal anodes are well-compatible with Na3SbS4 solid-state electrolyte, and the symmetrical solid-state battery exhibited a stable interface. Our strategy holds significant promise and has the potential for widespread application in theadvancement of high-energy sodium metal batteries and solid-state sodium batteries.