Artificial Solid Electrolyte Interface Research Articles

Integrated Configuration Design Strategy Via Cathode‐Gel Electrolyte With Forged Solid Electrolyte Interface Toward Advanced Lithium‐Sulfurized Polyacrylonitrile Batteries

AbstractLi‐SPAN batteries are a promising energy storage system, providing remarkable energy density and high Coulomb efficiency. However, the inherent sluggishness of the cathode's electrochemical kinetics and the instability of the Li anode hamper their cycle lifespan. In this study, a novel design of integrated configuration between cathode and electrolyte that addresses the challenges and promises to reshape the landscape of Li‐SPAN, significantly enhancing the cycling stability, is presented. An artificial solid electrolyte interface (ASEI) is forged to simultaneously stabilize the Li anode and improve the interfacial compatibility, enabling an all‐in‐one battery system. A vertically aligned cathode structure is achieved using directional ice templating, enabling efficient Li‐ion diffusion and enhancing electrochemical kinetics. The Li metal anode is coated with a MOF‐on‐COF ASEI, ensuring uniform Li+ deposition and high Li‐ion transference number (0.86). Dual surface engineering further enhances the Li‐SPAN cell, exhibiting a low capacity decay rate of 0.037% per cycle after 1000 cycles and superior C‐rate performance. This study introduces promising strategies for effectively overcoming the challenges associated with the SPAN cathode and Li anode and paves the way for the design of high‐performance Li‐SPAN batteries, unlocking their full potential in the field of advanced energy storage systems.

Rational Design of Three‐Dimensional Self‐Supporting Structure for Advanced Lithium Metal Anode

AbstractLithium metal anode (LMA) is the next generation of high‐performance electrochemical energy storage materials because of its unique advantages (high capacity and low redox potential). However, a discontinuous solid electrolyte interface (SEI) layer and lithium dendrites are formed during battery charging, leading to serious safety problems. For this purpose, researchers have devised many solutions, such as artificial SEI, modified current collector, and lithium alloy layer. Among them, the three‐dimensional (3D) current collector with a high surface area can not only reduce the local current density of lithium deposition but also promote lithium‐ion transfer and nucleation, thus inhibiting dendrite growth. In this progress report, we review the design of the LMA 3D‐structured current collector in accordance with the classification. Firstly, we discuss the latest development of advanced metal current collectors. Secondly, the 3D design of carbon‐based current collectors is summarized to improve the overall performance of lithium metal batteries (LMBs). Finally, the main challenges and development prospects of LMBs’ current collectors in the future are discussed.

In Situ Formation of Dense Polymers as Artificial Protective Layers for Lithium Metal Anodes

In order to improve the stability and safety of lithium (Li) metal anodes, an innovative artificial solid electrolyte interface (SEI) film of Li Poly (tert-butyl acrylate-co-ethyl acrylate-co-methacrylic acid) (LiPTBEM) has been designed. This thin and uniformly artificial SEI is stable, which can suppress the continuous side reactions between the electrolyte and Li metal, improve the stability of modified Li metal anodes, and achieve better electrochemical performance. Symmetric batteries with LiPTBEM exhibit significantly improved cycling stability, indicating that LiPTBEM is a promising artificial SEI film.

Hierarchical-structure and high-modulus aramid nanofiber membrane protective layer achieving high-performance lithium metal anode

Uniform lithium deposition and a stable solid electrolyte interface (SEI) film are crucial for realizing long-term stable operation of lithium metal batteries. Herein, aramid nanofiber (ANF) membrane with abundant amide bonds and hierarchical structure as an artificial solid electrolyte interface (SEI) was constructed through a simple two-step assembly strategy, which can effectively improve the interfacial compatibility and inhibit the growth of Li dendrites. A large number of polar amide bonds in ANF films can serve as anchor points to interact with Li+. The layered structure and hierarchical porosity of ANF films exhibits significantly improved mechanical strength and ability to suppress dendrites. Therefore, the constructed ANF membrane can homogenize the lithium flux during lithium plating/stripping process, inhibit the formation of hot spots, and promote the formation of a uniform SEI layer under these synergistic effects. The ANF modified Li (ANF@Li) anodes exhibit significantly improved electrochemical performance, stable cycling for 2500 h at high current density (10 mA cm−2) and 2500 h at high capacity (10 mAh cm−2). In addition, ANF@Li anodes showed a long life over 2800 h at 5 mA cm−2 and 10 mAh cm−2, which enables the ANF@Li anode to be the promising candidate for the next generation of high-power-density and high-energy–density batteries.

Reactive Polymer as Artificial Solid Electrolyte Interface for Stable Lithium Metal Batteries

AbstractLithium (Li) metal anodes have the highest theoretical capacity and lowest electrochemical potential making them ideal for Li metal batteries (LMBs). However, Li dendrite formation on the anode impedes the proper discharge capacity and practical cycle life of LMBs, particularly in carbonate electrolytes. Herein, we developed a reactive alternative polymer named P(St‐MaI) containing carboxylic acid and cyclic ether moieties which would in situ form artificial polymeric solid electrolyte interface (SEI) with Li. This SEI can accommodate volume changes and maintain good interfacial contact. The presence of carboxylic acid and cyclic ether pendant groups greatly contribute to the induction of uniform Li ion deposition. In addition, the presence of benzyl rings makes the polymer have a certain mechanical strength and plays a key role in inhibiting the growth of Li dendrites. As a result, the symmetric Li||Li cell with P(St‐MaI)@Li layer can stably cycle for over 900 h under 1 mA cm−2 without polarization voltage increasing, while their Li||LiFePO4 full batteries maintain high capacity retention of 96 % after 930 cycles at 1C in carbonate electrolytes. The innovative strategy of artificial SEI is broadly applicable in designing new materials to inhibit Li dendrite growth on Li metal anodes.

Reactive Polymer as Artificial Solid Electrolyte Interface for Stable Lithium Metal Batteries.

Lithium (Li)metal anodes have the highest theoretical capacity and lowest electrochemical potential making them ideal for Li metal batteries (LMBs). However, Li dendrite formation on the anode impedes the proper discharge capacity and practical cycle life of LMBs, particularly in carbonate electrolytes.Herein, we developed a reactive alternative polymer namedP(St-MaI) containing carboxylic acid and cyclic ether moieties which would in-situform artificial polymeric solid electrolyte interface (SEI) with Li. This SEI can accommodate volume changes and maintain good interfacial contact. The presence of carboxylic acid and cyclic ether pendant groups greatly contribute to the induction of uniform Li ion deposition. In addition, the presence of benzyl rings makes the polymer have a certain mechanical strength and plays a key role in inhibiting the growth of Lidendrites. As a result, the symmetric Li||Li cell with P(St-MaI)@Li layer can stably cycle for over 900 h under 1 mA cm-2without polarization voltage increasing, while their Li||LiFePO4full batteries maintain high capacity retention of 96% after 930 cycles at 1C in carbonate electrolytes.The innovative strategy of artificialSEI is broadly applicable in designing new materials to inhibit Li dendrite growth on Li metal anodes.

Nanometer-Thick Gallic Acid Coatings Enhance the Electrochemical Performance of Silicon Anodes

Due to the drawbacks of huge volume expansion upon lithiation/delithiation and surface corrosion by the electrolyte, silicon (Si) anodes for lithium ion batteries (LIBs) suffered from rapid capacity degradation. Herein, nano-Si was simply treated with a gallic acid (GA) solution to cover the Si surface with a nanometer-thick GA-layer. During surface treatment, GA formed an irreversible cross-linking structure, and it can be bonded to the surface of nano-Si via hydrogen bonds. The resulted nano-Si@GA-1 sample (mSi/mGA = 10:1) exhibited an initial coulombic efficiency as high as 89.8% and a high charge capacity of 2979 mA h g–1 at a current density of 100 mA g–1. It can be demonstrated by the facilitated Li+ diffusion and reduced Li+ consumption by the surface GA-layer containing immense −OH and −COOH groups, acting as an artificial solid–electrolyte interface (SEI) film. Moreover, the formed GA-layer also effectively suppressed volume expansion and delamination of the Si electrode, leading to the superior stability of nano-Si@GA. A charge capacity of 1567 mA h g–1 was retained after 300 cycles tested at 1 A g–1 for the nano-Si@GA-1 electrode, among the best values of reported Si materials. Overall, our prepared nano-Si@GA via a facile route is promising for the practical application of LIBs as an anode material.

A porous lithium metal anode with an artificial solid electrolyte interface fabricated by a facile process

Lithium metal batteries (LMBs) have been considered a next-generation energy storage system. However, dendrite growth on lithium metal anode has critical issues with poor Coulombic efficiency and safety problems such as short-circuiting. Moreover, the continuous growth of dendrites leads to severe volume expansion of the electrode. To solve these problems, we suggest a lithium metal anode with a porous structure covered by artificial solid electrolyte interphase (SEI) layer. The porous lithium metal anode with the artificial SEI layer is prepared simply by dissolving lithium salt (lithium bis(fluorosulfonyl)imide, LiFSI) from a pellet of the mixture of lithium metal powder and lithium salt. In contrast to planar lithium metal foil, the porous structure decreases areal current density and reduces the possibility to form long dendrites penetrating the separator. Also, the artificial SEI layer with a porous structure induces uniform plating of lithium above and inside the lithium metal anode. As a result, the symmetric cells with the porous lithium metal anode show enhanced cycle life and rate capability compared to the anode prepared with bare lithium metal powder. Furthermore, the full cell assembled with the porous lithium metal anode and NCM811 cathode also shows significantly higher rate capability than the bare lithium metal anode. Our results provide a better understanding for designing a porous lithium metal anode with an inherent SEI layer for high-capacity and high-rate lithium metal batteries.

In Situ Artificial Hybrid SEI Layer Enabled High‐Performance Prelithiated SiOx Anode for Lithium‐Ion Batteries

AbstractConsidered the promising anode material for next‐generation high‐energy lithium‐ion batteries, SiOx has been slow to commercialize due to its low initial Coulombic efficiency (ICE) and unstable solid electrolyte interface (SEI) layer, which leads to reduced full‐cell energy density, short cycling lives, and poor rate performance. Herein, a novel strategy is proposed to in situ construct an artificial hybrid SEI layer consisting of LiF and Li3Sb on a prelithiated SiOx anode via spontaneous chemical reaction with SbF3. In addition to the increasing ICE (94.5%), the preformed artificial SEI layer with long‐term cycle stability and enhanced Li+ transport capability enables a remarkable improvement in capacity retention and rate capability for modified SiOx. Furthermore, the full cell using Li(Ni0.8Co0.1Mn0.1)O2 and a pre‐treated anode exhibits high ICE (86.0%) and capacity retention (86.6%) after 100 cycles at 0.5 C. This study provides a fresh insight into how to obtain stable interface on a prelithiated SiOx anode for high energy and long lifespan lithium‐ion batteries.

Roll-to-roll solvent-free manufactured electrodes for fast-charging batteries

Roll-to-roll solvent-free manufactured electrodes for fast-charging batteries

Self-Assembled Protein Nanofilm Regulating Uniform Zn Nucleation and Deposition Enabling Long-Life Zn Anodes.

Rechargeable zinc-ion batteries (RZIBs) have gained promising attention as a feasible alternative for large-scale energy storage by the virtue of their intrinsic security, environmental benignity, low cost, and high volumetric capacity (5849mAhcm-3 ). Nevertheless, the deep-rooted issues of dendrite formation and side reactions in unstable Zn metal anode have impeded RZIBs from being dependably deployed in their proposed applications. Herein, silk fibroin (SF) and lysozyme (ly), as natural biomacromolecules with abundant polar groups arranged in polypeptide backbones, are in situ self-assembled on the Zn anode surface to construct a homogeneous and compact protein nanofilm. Such protein nanofilm protecting layer presents a negative charge surface and significantly regulates Zn2+ deposition behavior. Meanwhile, synergistic flexible and robust features of protein nanofilm function as artificial solid electrolyte interface (SEI), accommodates the dynamic volume deformation during deposition/dissolution, and blocks corrosion of side reactions. Consequently, the electrochemical stability of protein nanofilm-modified Zn anode is greatly improved, with an excellent extended lifespan of over 1100h at a high current density of 10mAcm-2 and a high cycling capacity of 10mAhcm-2 , corresponding to a high depth of discharge (83% DODZn ). Furthermore, the highly reversible Zn electrode remarkably improved the overall performance of MnO2 ||Zn full-cells.

Boron‐Doped Electrolytes as Interfacial Modifiers for High‐Rate Stable Lithium Metal Batteries

AbstractIn this article BF3 etching is applied to fabricate basic SEI (B‐SEI) layers enriched with LiF and LixBFy. Artificial solid electrolyte interface (A‐SEI) with a “stromatolite” structure is formed on top of the B‐SEI growth during the charge‐discharge cycles. The structure of A‐SEI is characterized laterally and longitudinally by distribution of TEM elements and depth‐profile XPS, providing evidence for the elucidation of a new lattice‐tuning Li+ “layered” deposition‐type SEI structure. At the same time, the SEI is kept from electrolyte erosion fracturing during deposition, resulting in the growth of dendrites along the fracture and significantly enhanced cycling stability under high‐rate cycling conditions. In particular, A‐SEI endows significantly enhanced cycling capability to the full battery at high cycling rate and high current density. The full cell of A‐SEI@Li||LiPF6||LFP exhibits an extended lifetime after 2000 cycles at current densities up to 10 C, and still process a CE above 99.0%.

Surface engineering toward stable lithium metal anodes.

The lithium (Li) metal anode (LMA) is susceptible to failure due to the growth of Li dendrites caused by an unsatisfied solid electrolyte interface (SEI). With this regard, the design of artificial SEIs with improved physicochemical and mechanical properties has been demonstrated to be important to stabilize the LMAs. This review comprehensively summarizes current efficient strategies and key progresses in surface engineering for constructing protective layers to serve as the artificial SEIs, including pretreating the LMAs with the reagents situated in different primary states of matter (solid, liquid, and gas) or using some peculiar pathways (plasma, for example). The fundamental characterization tools for studying the protective layers on the LMAs are also briefly introduced. Last, strategic guidance for the deliberate design of surface engineering is provided, and the current challenges, opportunities, and possible future directions of these strategies for the development of LMAs in practical applications are discussed.

Construction of high elastic artificial SEI for air-stable and long-life lithium metal anode

Compared with other anode materials, Li metal anode has higher capacity density and lower electrode potential, which has been considered as one of the most promising anode materials. However, the unstable solid electrolyte interface (SEI) leads to Li dendrite growth and the infinite volumetric expansion of Li metal, which seriously hinders the stability and cycle life of Li metal batteries (LMBs). Here, a polyurethane elastomer (TPU) material with high elasticity and air stability is used as the artificial SEI of Li metal anode. Its designed synergistic effect of soft chain forging and hard chain segments not only gives TPU artificial SEI layer good electronic insulation, Li ion conductivity, Li dendrite growth inhibition, high elastic modulus and flexibility to adapt to Li volume expansion, but also has a significant air protection effect on the Li metal surface, so that the TPU coated Li foil will not occur obvious oxidation phenomenon after being placed in air for 45 min. The Li symmetric battery modified by TPU achieved a stable and long-term cycle performance of 1300 h at 1 mA/cm2, it can also cycle stably at a high current density of 10 mA/cm2. The Coulomb efficiency of the modified Li/Cu half-cell maintains at above 97% after 400 cycles. In addition, the full cell with LiFePO4 cathode also delivers a very excellent long cycle stability with 90% capacity retention after 1500 cycles at 5 C. This surface modification strategy of SEI on lithium anode has has great research value and will help to improve the widely application of LMBs.

Superior plating/stripping performance through constructing an artificial interphase layer on metallic Mg anode

Rechargeable magnesium batteries (RMBs) have attracted tremendous attention in energy storage applications in term of high abundance, high specific capacity and remarkable safety of metallic magnesium (Mg) anode. However, a serious passivation of Mg anode in the conventional electrolytes leads to extremely poor plating/stripping performance, further hindering its applications. Herein, we propose a convenient method to construct an artificial interphase layer on Mg anode by substitution and alloying reactions between SbCl3 and Mg. This Sb-based artificial interphase layer containing mainly MgCl2 and Mg3Sb2 endows the significantly improved interfacial kinetics and electrochemical performance of Mg anode. The overpotential of Mg plating/stripping in conventional Mg(TFSI)2/DME electrolytes is vastly reduced from over 2 V to 0.25–0.3 V. Combining experiments and calculations, we demonstrate that under the uniform distribution of MgCl2 and Mg3Sb2, an electric field with a favorable potential gradient is formed on the anode surface, which enables swift Mg2+ migration. Meanwhile, this layer can inhibit the decomposition of electrolytes to protect anode. This work provides an in-depth exploration of the artificial solid-electrolyte interface (SEI) construction, and a more achievable and safe path to realize the application of metallic Mg anode in RMBs.

Mass-producible in-situ amorphous solid/electrolyte interface with high ionic conductivity for long-cycling aqueous Zn-ion batteries

Although aqueous Zn-ion batteries (aZIBs) have garnered significant attention, they are yet to be commercialized due to severe corrosion and dendrite growth on Zn anodes. In this work, an artificial solid-electrolyte interface (SEI) with amorphous structure was created in-situ on the anode by immersing Zn foil in ethylene diamine tetra(methylene phosphonic acid) sodium (EDTMPNA5) liquid. This facile and effective method provides the possibility for Zn anode protection in large-scale applications. Experimental results, combined with theoretical calculations, indicate that the artificial SEI remains intact and adheres tightly to the Zn substrate. The negatively-charged phosphonic acid groups and disordered inner structure offer adequate sites for rapid Zn2+ transference and facilitate [Zn(H2O)6]2+ desolvation during charging/discharging. Due to the synergistic effect of the aforementioned advantages, the artificial SEI endows high Coulombic efficiency (CE, 99.75%) and smooth Zn deposition/stripping under the SEI. The symmetric cell exhibits a long cycling life of over 2400 h with low-voltage hysteresis. Additionally, full cells with MVO cathodes demonstrate the superiority of the modified anodes. This work provides insight into the design of in-situ artificial SEI on the Zn anode and self-discharge suppression to expedite the practical application of aZIBs.

Long-Lifespan Lithium Metal Batteries Enabled by a Hybrid Artificial Solid Electrolyte Interface Layer.

Lithium metal batteries based on metallic Li anodes have been recognized as competitive substitutes for current energy storage technologies due to their exceptional advantage in energy density. Nevertheless, their practical applications are greatly hindered by the safety concerns caused by lithium dendrites. Herein, we fabricate an artificial solid electrolyte interface (SEI) via a simple replacement reaction for the lithium anode (designated as LNA-Li) and demonstrate its effectiveness in suppressing the formation of lithium dendrites. The SEI is composed of LiF and nano-Ag. The former can facilitate the horizontal deposition of Li, while the latter can guide the uniform and dense lithium deposition. Benefiting from the synergetic effect of LiF and Ag, the LNA-Li anode exhibits excellent stability during long-term cycling. For example, the LNA-Li//LNA-Li symmetric cell can cycle stably for 1300 and 600 h at the current densities of 1 and 10 mA cm-2, respectively. Impressively, when matching with LiFePO4, the full cells can steadily cycle for 1000 times without obvious capacity attenuation. In addition, the modified LNA-Li anode coupled with the NCM cathode also exhibits good cycling performance.

In‐Situ Constructing A Heterogeneous Layer on Lithium Metal Anodes for Dendrite‐Free Lithium Deposition and High Li‐ion Flux

AbstractConstructing efficient artificial solid electrolyte interface (SEI) film is extremely vital for the practical application of lithium metal batteries. Herein, a dense artificial SEI film, in which lithiophilic Zn/LixZny are uniformly but nonconsecutively dispersed in the consecutive Li+‐conductors of LixSiOy, Li2O and LiOH, is constructed via the in situ reaction of layered zinc silicate nanosheets and Li. The consecutive Li+‐conductors can promote the desolvation process of solvated‐Li+ and regulate the transfer of lithium ions. The nonconsecutive lithiophilic metals are polarized by the internal electric field to boost the transfer of lithium ions, and lower the nucleation barrier. Therefore, a low polarization of ≈50 mV for 750 h at 2.0 mA cm−2 in symmetric cells, and a high capacity retention of 99.2 % in full cells with a high lithium iron phosphate areal loading of ≈13 mg cm−2 are achieved. This work offers new sights to develop advanced alkali metal anodes for efficient energy storage.

In-Situ Constructing A Heterogeneous Layer on Lithium Metal Anodes for Dendrite-Free Lithium Deposition and High Li-ion Flux.

Constructing efficient artificial surface electrolyte interface (SEI) film is extremely vital for the practical application of lithium metal batteries. Herein, a dense artificial SEI film, in which lithiophilic Zn/LixZny are uniformly but nonconsecutively dispersed in the consecutive Li+-conductors of LixSiOy, Li2O and LiOH, is constructed via the in-situ reaction of layered zinc silicate nanosheets and Li. The consecutive Li+-conductors can promote the desolvation process of solvated-Li+ and regulate the transfer of lithium ions. The nonconsecutive lithiophilic metals are polarized by the internal electric field to boost the transfer of lithium ions, and lower the nucleation barrier. Therefore, a low polarization of ~50 mV for 750 h at 2.0 mA cm-2 in symmetric cells, and a high capacity retention of 99.2% in full cells with a high LFP areal loading of ~13 mg cm-2 are achieved. This work offers new sights to develop advanced alkali metal anodes for efficient energy storage.

A Single Mg Ion-conductive Polymer-coated MgCo2O4 for Mg Rechargeable Batteries

A method for coating cathode active material for magnesium-ion batteries was proposed using polymer, a poly(styrene-4-sulfonyl trifluoromethane sulfonyl)imide Mg salt (PSTFSI-Mg) having a trifluoromethane sulfonyl imide side group. A cathode active material, MgCo2O4 (MCO), was used and spray-dried with PSTFSI-Mg. After preparing the cathode, the Mg battery test was performed with glyme electrolyte solution. The polymer-coated MCO cathode-based coin cell showed good cyclability with moderate discharge capacity around 45 mAh g−1, and this indicates that the polymer thin layer on the MCO surface probably acts as artificial solid electrolyte interface and prevents electrolyte decomposition.