Solid Electrolyte Interface Research Articles

Engineering Moderately Lithiophilic Paper-Based Current Collectors with Variable Solid Electrolyte Interface Films for Anode-Free Lithium Batteries.

Compared to traditional lithium metal batteries, anode-free lithium metal batteries use bare current collectors as an anode instead of Li metal, making them highly promising for mass production and achieving high-energy density. The current collector, as the sole component of the anode, is crucial in lithium deposition-stripping behavior and greatly impacts the rate of Li depletion from the cathode. In this study, to investigate the lithiophilicity effect of the current collector on the solid electrolyte interface (SEI) film construction and cycling performance of anode-free lithium batteries, various lightweight paper-based current collectors were prepared by electroless plating Cu and lipophilic Ag on low-dust paper (LDP). The areal densities of the as-prepared LDP@Cu, LDP@Cu-Ag, and LDP@Ag were approximately 0.33 mg cm-2. The use of lipophilic Ag-coated collectors with varying loadings allowed for the regulation of lipophilicity. The impacts of these collectors on the distribution of SEI components and Li depletion rate in common electrolytes were investigated. The findings suggest that higher loadings of lipophilic materials, such as Ag, on the current collector increase its lipophilicity but also lead to significant Li depletion during the cycling process in full-cell anode-free Li metal batteries. Thus, moderately lithiophilic current collectors, such as LDP@Cu-Ag, show more potential for Li deposition and striping and stable SEI with a low speed of Li depletion.

Anion Chemistry towards On-Site Construction of Solid-Electrolyte Interface for Highly Stable Metallic Zn Anode.

Reversibility of metallic Zn anode serves as the corner stone for the development of aqueous Zn metal battery, which motivates scrutinizing the electrolyte-Zn interface. As the representative organic zinc salt, zinc trifluorosulfonate (Zn(OTf)2) facilitates a broad class of aqueous electrolytes, however, the stability issue of Zn anode remains crucial. The great challenge lies in the lack of Zn anode protection by the pristinely formed surface structure in aqueous Zn(OTf)2 electrolytes. Accordingly, an electrochemical route was developed to grow a uniform zinc trifluorosulfonate hydroxide (ZTH) layer on Zn anode as an artificial SEI, via regulation on metal dissolution and strong coordination ability of zinc ions. Co-precipitation was proposed to be the formation mechanism for the artificial SEI, where the reduction stability of OTf‾ anion and the low-symmetry layer structure of ZTH was unmasked. This artificial SEI favors interfacial kinetics, depresses side reactions, and well maintains its integrity during cycling, leading to a prolonged lifespan of Zn stripping/plating with a high DOD of ~85%, and an improved cycling stability of ~92% retention rate for V2O5/Zn cell at 1 A g-1. The unveiled role of anion on Zn anode drives the contemplation on the surface chemistry for the blooming aqueous rechargeable battery.

Amide coupled Si-rGO hybrids as anode material for lithium-ion batteries

Despite silicon (Si) having a high specific capacity of 4200 mA h/g, it undergoes significant expansion in volume during lithiation. In order to alleviate the significant increase in volume that occurs in silicon nanoparticles (SiNPs) of lithium-ion batteries, herein we report covalently modified SiNP contained within reduced graphene oxide (rGO) sheets as an anode material in lithium-ion batteries (LIBs). The structural modification of SiNP could effectively mitigate the increase in volume while preserving its outstanding electrochemical properties. Graphene oxide (GO) undergoes chemical modification and functionalization by a simple and efficient method using microwave-assisted sonochemical approach. The procedure entails grafting carboxyl functionalized silicon nanoparticles (C-Si) to amine-functionalized reduced graphene oxide (NH2-rGO) to produce a Si-rGO hybrid via amide linkage. This hybrid reduces the problem of volume expansion in Si anodes by dissipating substantial changes in volume and minimizing direct contact between SiNPs and the electrolyte. The formation of a robust solid electrolyte interface (SEI) layer improves the specific capacity and durability of the anode material. We observed that the Si-rGO 2 hybrid (containing 44 wt% Si) exhibited a relatively higher specific capacity of 1604 mA h/g during the initial cycle at C/10 rate when compared to other hybrid systems, such as Si-rGO 1, Si-rGO 2, Si-rGO 3 with bare SiNP, and SRGO composite (without amide linkage). Additionally, it maintained a capacity of approximately 1000 mA h/g at C/2 rate for more than 125 cycles. Thus, enhanced specific capacity, cycling stability, electrode conductivity, and lithiation are made possible due to the structural modification of SiNPs.

Lithium fluoride additive helps construct stable electrode-electrolyte interfaces to boost the performance of Mg-S batteries

Most magnesium electrolytes react with the Mg anode surface to form a non-favorable passive layer that inhibits shuttling of the Mg ions and results in the short cycle life of the Mg cells. In this work, we probe LiF as an effective electrolyte additive to address the challenges of electrolyte degradation, Mg anode passivation, and polysulfide shuttle. The key to our strategy lies in modifying the halogen-free electrolytes (HFE) electrolyte-based Mg(NO3)2·6H2O salt dissolved in acetonitrile (ACN) and tetra ethylene glycol dimethyl ether (G4) with LiF additives, which play a crucial role in engineering stable electrolyte interfaces. These additives alter the chemical composition of the solid electrolyte interface (SEI) layer on the surface of the Mg anode, enabling low overpotential of Mg2+ extraction/insertion, improving the Mg2+ transference, and enhancing the electrochemical performance of the electrolyte. The Mg-S cell with modified electrolyte delivers a high discharge capacity of over 400 mAh g−1 for >10 cycles, compared with the short cycle life in the case of using a blank electrolyte. This remarkable performance underscores the potential of our findings in advancing magnesium sulfur battery technology.

Covalent Triazine Based Frameworks with Donor‐Donor‐π‐Acceptor Structures for Dendrite‐Free Lithium Metal Batteries

AbstractThe appearance of disordered lithium dendrites and fragile solid electrolyte interfaces (SEI) significantly hinder the serviceability of lithium metal batteries. Herein, guided by theoretical predictions, a multi‐component covalent triazine framework with partially electronegative channels (4C‐TA0.5TF0.5‐CTF) is incorporated as a protective layer to modulate the interface stability of the lithium metal batteries. Notably, the 4C‐TA0.5TF0.5‐CTF with optimized electronic structure at the molecular level by fine‐tuning the local acceptor‐donor functionalities not only enhances the intermolecular interaction thereby providing larger dipole moment and improved crystallinity and mechanical stress, but also facilitates the beneficial effect of lithiophilic sites (C−F bonds, triazine cores, C=N linkages and aromatic rings) to further regulate the migration of Li+ and achieve a uniform lithium deposition behavior as determined by various in‐depth in/ex situ characterizations. Due to the synergistic effect of multi‐component organic functionalities, the 4C‐TA0.5TF0.5‐CTF modified full cells perform significantly better than the common two/three‐component 2C‐TA‐CTF and 3C‐TF‐CTF electrodes, delivering an excellent capacity of 116.3 mAh g−1 (capacity retention ratio: 86.8 %) after 1000 cycles at 5 C and improved rate capability. This work lays a platform for the prospective molecular design of improved organic framework relative artificial SEI for highly stable lithium metal batteries.

Introducing nanodiamond-modified electrolyte to realize high capacity and rate performance of sodium ion batteries

The solid electrolyte interface (SEI) acts as a channel for sodium ions from electrolyte to anode, its structure and chemical properties are crucial to the Coulombic efficiency, cycling stability, and even safety of rechargeable batteries. In this work, using bio-carbon as an anode, and nanodiamond (ND) as electrolyte additive, the relation between ND and SEI properties and sodium storage performance is explored. It is found that ND is transferred to the surface of bio-carbon anode and induces the formation of stable and inorganic-rich SEI (such as NaF and Na2O). Besides, the introduction of ND significantly increases the ionic conductivity. The sodium-ion batteries with ND-electrolyte exhibit a superior reversible capacity of 340 mA g−1 after 400 cycles at 0.5 A g−1, long-term cycling stability (183 mA g−1 over 1000 cycles at 5 A g−1), and remarkable rate performance (157 mA h g−1 at 10 A g−1), which is attributed to the fact that the presence of ND could provide additional storage sites and improve the stability of SEI. This study provides valuable guidance for improving the electrochemical performance of electrode materials by regulating the SEI in the optimal electrolyte.

Electrochemical Performance of Deposited LiPON Film/Lithium Electrode in Lithium-Sulfur Batteries.

This paper presents a composed lithium phosphate (LiPON) solid electrolyte interface (SEI) film which was coated on a lithium electrode via an electrodeposit method in a lithium-sulfur battery, and the structure of the product was characterized through infrared spectrum (IR) analysis, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), environment scanning electron microscope (ESEM), etc. Meanwhile, the electrochemical impedance spectrum and the interface stability of the lithium electrode with the LiPON film was analyzed, while the coulomb efficiency and the cycle life of the lithium electrode with the LiPON film in the lithium-sulfur battery were also studied. It was found that this kind of film can effectively inhibit the charge from transferring at the interface between the electrode and the solution, which can produce a more stable interface impedance on the electrode, thereby improving the interface contact with the electrolyte, and effectively improve the discharge performance, cycle life, and the coulomb efficiency of the lithium-sulfur battery. This is of great significance for the further development of solid electrolyte facial mask technology for lithium-sulfur batteries.

Designing electrolytes for enhancing stability and performance of lithium-ion capacitors at large-scale cylindrical cells

This study investigates the impact of fluorinated ethylene carbonate (FEC) as a co-solvent in the electrolytes of large-scale lithium-ion capacitors (LICs), an area previously unexplored. Our comprehensive analysis integrates electrochemical analysis, gas detection, and surface chemical examination to assess the performance and stability of a 1.2 M LiPF6 electrolyte system. We explored various formulations, including a standard EC/EMC/DEC mixed solvent and newly designed electrolytes with FEC additions, such as EC/EMC/DEC/FEC and DMC/FEC blends. Our findings demonstrate that the DMC/FEC blend matches and even surpasses the capacity retention of traditional electrolytes, suggesting enhanced long-term stability. FEC's presence significantly reduces electrolyte decomposition, as confirmed by in situ Differential Electrochemical Mass Spectrometry and ex-situ gas chromatography. Further, surface chemical analysis highlighted the formation of a stable, LiF-rich solid electrolyte interface (SEI) when FEC is included, thereby improving the chemical stability of the system. These results underline FEC's crucial role in optimizing electrolyte compositions, thus advancing the development of more efficient and durable LIC systems. FEC's integration into LIC electrolytes represents a significant breakthrough, enhancing overall performance and longevity, with broad implications for the application of LICs in various technologies.

In‐Situ Solid Electrolyte Interface via Dual Reaction Strategy for Highly Reversible Zinc Anode

AbstractIn situ construction of solid electrolyte interfaces (SEI) is an effective strategy to enhance the reversibility of zinc (Zn) anodes. However, in situ SEI to afford high reversibility under high current density conditions (≥20 mA cm−2) is highly desired yet extremely challenging. Herein, we propose a dual reaction strategy of spontaneous electrostatic reaction and electrochemical decomposition for the in situ construction of SEI, which is composed of organic‐rich upper layer and inorganic‐rich inner layer. Particularly, in situ SEI performs as “growth binder“ at small current density and “orientation regulator” at high current density, which significantly suppresses side reactions and dendrite growth. The in situ SEI affords the record‐breaking reversibility of Zn anode under practical conditions, Zn//Zn symmetric cells can stably cycle for over 1300 h and 400 h at current densities of 50 mA cm−2 and 100 mA cm−2, respectively, showcasing an exceptional cumulative capacity of 67.5 Ah cm−2. Furthermore, the practicality of this in situ SEI is verified in Zn//PANI pouch cells with high mass loading of 25.48 mg cm−2. This work provides a universal strategy to design advanced SEI for practical Zn‐ion batteries.

In-Situ Solid Electrolyte Interface via Dual Reaction Strategy for Highly Reversible Zinc Anode.

In situ construction of solid electrolyte interfaces (SEI) is an effective strategy to enhance the reversibility of zinc (Zn) anodes. However, in situ SEI to afford high reversibility under high current density conditions (≥20 mA cm-2) is highly desired yet extremely challenging. Herein, we propose a dual reaction strategy of spontaneous electrostatic reaction and electrochemical decomposition for the in situ construction of SEI, which is composed of organic-rich upper layer and inorganic-rich inner layer. Particularly, in situ SEI performs as "growth binder" at small current density and "orientation regulator" at high current density, which significantly suppresses side reactions and dendrite growth. The in situ SEI affords the record-breaking reversibility of Zn anode under practical conditions, Zn//Zn symmetric cells can stably cycle for over 1300 h and 400 h at current densities of 50 mA cm-2 and 100 mA cm-2, respectively, showcasing an exceptional cumulative capacity of 67.5 Ah cm-2. Furthermore, the practicality of this in situ SEI is verified in Zn//PANI pouch cells with high mass loading of 25.48 mg cm-2. This work provides a universal strategy to design advanced SEI for practical Zn-ion batteries.

In Situ Self‐Polymerization of Thioctic Acid Enabled Interphase Engineering Towards High‐Performance Lithium–Sulfur Battery

AbstractLithium–sulfur (Li–S) batteries possess high theoretical energy density, whereas the shuttle effect of polysulfides and the uncontrollable lithium (Li) dendrites seriously reduce the reversible capacity and cycling lifespan. Constructing an interphase to address the issues in both the cathode and anode simultaneously is significant but still challenging. In this study, a strategy of functionalizing commercial polypropylene (PP) separators is proposed by in situ poly(thioctic acid) (PTA) polymerization. Compared with the conventional separator modifications, the ring‐opening polymerization methodology initiated by heat is more facile and environment‐friendly without changing the nanostructures among the porous separators. On the cathode side, the PTA‐coated separator (PTA‐PP) blocks the shuttle of polysulfides through the electrostatic interaction. On the anode side, the PTA‐coated generates a lithium fluoride (LiF)‐rich solid electrolyte interface (SEI), identified by cryo‐transmission electron microscopy (cryo‐TEM), to accelerate the Li+ diffusion and inhibit the growth of Li dendrites. Due to the interphases constructed by the PTA‐PP separator, the Li–S cells exhibit excellent long‐term cycling in which the capacity retention rate is more than 76% after 700 cycles at 0.5 C. The in situ elaborate modification strategy may provide insights into the high‐performance separator design to promote the potentially large‐scale applications of Li–S batteries.

Collagen‐Mediated Solvent Sheathing and Derived Interfacial Manipulation Toward Ultrahigh‐Rate Zn Anodes

AbstractThe zinc (Zn) anode in zinc‐ion batteries suffers from potential defects such as wild dendrite growth, severe Zn corrosion, and violent hydrogen evolution reaction, inducing erratic interfacial charge transfer kinetics, which eventually leads to electrochemical failure. Here, collagen, a biomacromolecule, is added to achieve the reconstruction of the electrolyte hydrogen‐bonding network and the modification of the derived Zn interface. Benefiting from the electronegativity advantage of amino groups (‐NH2) in collagen, the Zn (002) crystal plane is preferentially exposed and the solid electrolyte interface (SEI) rich in ZnF2 and Zn3N2 promotes the rapid charge transfer of Zn anode. Thence, an impressive cumulative capacity of 7,500 mAh cm−2 at 30 mA cm−2 is achieved and the assembled Zn|VO2 cell exhibited robust cycle reversibility even when subject to a maximum current of 100 A g−1 and an ultra‐long cycle life of 20,000 cycles at 50 A g−1, with a single‐cycle capacity loss as low as 0.0021%. Such a convenient strategy of solvent sheathing regulation and derived interfacial manipulation opening up a promising universal approach toward long‐life and high‐rate Zn anodes.

In-situ construction of solid electrolyte interphase for stable zinc anode via synergy of electrochemical reduction and chemical precipitation

Aqueous zinc ion batteries (ZIBs) feature high theoretical capacity, low cost, and high safety, but they suffer from moderate reversibility arising from electrolyte decomposition, Zn corrosion/passivation, and dendrite growth. To address this issue, an effective strategy is to construct a functional solid electrolyte interface (SEI) in situ. However, this is substantially challenging owing to the severe hydrogen evolution reaction (HER) and a lack of substances that can be decomposed to form SEI in the aqueous electrolytes. Herein, we propose the fabrication of a stable SEI in situ via a synergistic electrochemical reduction-chemical precipitation approach. By chemically capturing the hydroxide ions (OH−) from HER, fatty acid methyl ester ethoxylate (FMEE), as an aqueous electrolyte additive, undergoes ester group hydrolysis following by a combination with Zn2+ to form insoluble fatty acid-zinc, enabling intelligent growth of a SEI on the Zn anode surface. As a result, the enhanced Zn anode exhibits a prolonged cycling life of up to 2700 h at 1 mA/cm2 and 1 mAh/cm2. The Zn-V2O5 full cell with the designed electrolyte demonstrates excellent rate capability and significantly improved cycling stability. This study presents a simple and practical strategy for in-situ formation of SEI in aqueous electrolytes, advancing the development of high-performance aqueous batteries.

Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs). The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effective in enhancing the Na+ storage capability, however, a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly desirable. Herein, we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry. A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree, which provides more Na+ storage sites. In-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy (FTIR/EIS) and X-ray photoelectron spectroscopy (XPS) analysis demonstrate the presence of more BC3 and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI, which leads to facilitated charge transfer and excellent rate performance. As a result, the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling performance. In general, this work unravels the critical role of boron doping in optimizing the pore structure, interface chemistry and diffusion kinetics of hard carbon, which enables rational design of sodium-ion battery anode with enhanced Na+ storage performance.

Noncovalent Interactions-Driven Self-Assembly of Polyanionic Additive for Long Anti-Calendar Aging and High-Rate Zinc Metal Batteries.

Zinc anodes of zinc metal batteries suffer from unsatisfactory plating/striping reversibility due to interfacial parasitic reactions and poor Zn2+ mass transfer kinetics. Herein, methoxy polyethylene glycol-phosphate (mPEG-P) is introduced as an electrolyte additive to achieve long anti-calendar aging and high-rate capabilities. The polyanionic of mPEG-P self-assembles via noncovalent-interactions on electrode surface to form polyether-based cation channels and in situ organic-inorganic hybrid solid electrolyte interface layer, which ensure rapid Zn2+ mass transfer and suppresses interfacial parasitic reactions, realizing outstanding cycling/calendar aging stability. As a result, the Zn//Zn symmetric cells with mPEG-P present long lifespans over 9000 and 2500 cycles at ultrahigh current densities of 120 and 200mA cm-2, respectively. Besides, the coulombic efficiency (CE) of the Zn//Cu cell with mPEG-P additive (88.21%) is much higher than that of the cell (36.4%) at the initial cycle after the 15-day calendar aging treatment, presenting excellent anti-static corrosion performance. Furthermore, after 20-day aging, the Zn//MnO2 cell exhibits a superior capacity retention of 89% compared with that of the cell without mPEG-P (28%) after 150 cycles. This study provides a promising avenue for boosting the development of high efficiency and durable metallic zinc based stationary energy storage system.

Functional ternary salt construction enabling an in-situ Li3N/LiF-enriched interface for ultra-stable all-solid-state lithium metal batteries

Poly(ethylene oxide)-based polymer all-solid-state lithium metal batteries (ASSLBs) have received widespread attention due to their low cost, good process ability, and high energy density. Nevertheless, the growth of Li dendrites within polymer solid-state electrolytes damages the reversibility of Li anodes and still impedes their widespread application. One efficient strategy is to construct a superior solid electrolyte interface. Herein, a stable interface enriched with Li3N and LiF is in-situ formed between Li anode and a ternary salt electrolyte. This ternary salt electrolyte is innovatively designed by introducing lithium bis(trifluoromethane sulfonyl)imide (LiTFSI), lithium bis(fluorosulfonyl)imide (LiFSI), and LiNO3 to poly(ethylene oxide) matrix. Surface characterization indicates that LiNO3 and LiFSI contribute to forming a Li3N-LiF-enriched interface and meanwhile LiTFSI ensures excellent conductivity. Theoretically, among various Li compound components, Li3N has high ionic conductivity, which is beneficial for reducing overpotential, while LiF has high interfacial energy which can enhance nucleation energy and suppress the formation of Li dendrites. The experimental results show that ASSLBs coupled with LiFePO4 cathode display extremely excellent cycle stability approximately 2200 cycles at 2 C, with a final and corresponding discharge specific capacity of 96.7 mA h g−1. Additionally, a schematic illustration of the working mechanism for the Li3N-LiF interface is proposed.

Enhanced solid-electrolyte interface efficiency for practically viable hydrogen-air fuel cell systems

Proton exchange membrane fuel cells (PEMFCs) provide an appealing sustainable energy system, with the solid-electrolyte membrane playing a crucial role in its overall performance. Currently, sulfonated poly(1,4-phenylene ether-ether sulfone) (SPEES), an aromatic hydrocarbon polymer, has garnered considerable attention as an alternative to Nafion polymers. However, the long-term durability and stability of SPEES present a significant challenge. In this context, we introduce a potential solution in the form of an additive, specifically a core–shell-based amine-functionalized iron titanate (A–Fe2TiO5), which holds promise for improving the lifetime, proton conductivity, and power density of SPEES in PEMFCs. The modified SPEES/A–Fe2TiO5 composite membranes exhibited notable characteristics, including high water uptake, enhanced thermomechanical stability, and oxidative stability. Notably, the SPEES membrane loaded with 1.2 wt% of A–Fe2TiO5 demonstrates a maximum proton conductivity of 155 mS cm−1, a twofold increase compared to the SPEES membrane, at 80 °C under 100% relative humidity (RH). Furthermore, the 1.2 wt% of A–Fe2TiO5/SPEES composite membranes exhibited a maximum power density of 397.37 mW cm−2 and a current density of 1148 mA cm−2 at 60 °C under 100% RH, with an open-circuit voltage decay of 0.05 mV/h during 103 h of continuous operation. This study offers significant insights into the development and understanding of innovative SPEES nanocomposite membranes for PEMFC applications.

Low-Solvent-Coordination Solvation Structure for Lithium-Metal Batteries via Electric Dipole-Dipole Interaction.

Unveiling inherent interactions among solvents, Li+ ions, and anions are crucial in dictating solvation-desolvation kinetics at the electrode/electrolyte interface. Developing an electrolyte with a low ion-transport barrier and minimal solvent coordination in its interfacial solvation structure is essential for forming an anion-derived solid-electrolyte interface, a key component for high-performance Li-metal batteries. In this study, we harness electric dipole-dipole synergistic interactions to formulate an electrolyte with significantly reduced interfacial solvent coordination. Operando characterization and theoretical analysis reveal that 2-fluoropyridine (FPy) with high dipole preferentially adsorbs onto the Li metal surface. The adsorbed FPy molecule squeezes succinonitrile in the primary solvation sheath through steric hindrance, leading to the formation of an inorganic-rich interphase. Consequently, the introduction of FPy enhances the reversible capacity of the LiCoO2||Li cell, which maintains a capacity of 143 mAh g-1 after 500 cycles at a 1C rate. Moreover, the cycle life of LiCoO2 batteries with a limited supply of lithium extends from 120 cycles to over 200 cycles. These findings offer a strategy that can be applied broadly to design interfacial solvation structures for various metal-ion/metal-based batteries.

Constructing a Li–Zn lithiophilic layer by a scalable method of magnetron sputtering for a high-quality Li–B alloy anode

Lithium metal anodes offer high theoretical capacity and low redox potential but face challenges like dendritic growth, fragile solid electrolyte interface (SEI), "dead lithium" formation, and volume expansion. Composite anodes or artificial SEIs can address these issues, but often suffer from poor lithiophilicity and mass burdens. This study presents a Li–Zn–B alloy anode combining a Li–Zn lithiophilic layer with a bulk Li–B alloy. The Li–Zn lithiophilic layer, formed by magnetron sputtering of Zinc oxide (ZnO), improves surface lithiophilicity. Symmetrical cells with this alloy cycled stably for 1300 (1 mA cm−2, 1 mAh cm−2) and 550 h (2 mA cm−2, 2 mAh cm−2) with minimal overpotentials. The LiBZn||NCM811 full cell showed a specific discharge capacity of 130.8 mAh/g and stable Coulombic efficiency of 98.9 % after 300 cycles.

Rolling strategy for highly efficient preparation of phosphating interface enabled the stable lithium anode

Lithium metal anode has an ultra-high theoretical specific capacity and the lowest reduction potential, regarded as the next-generation anode material for high-energy-density batteries. However, the lithium metal anode suffers from the severe side reaction and Li dendrite growth caused by the inhomogeneous deposition of Li+ on the anode during the electrochemical cycling. Herein, a strategy is proposed to design an artificial solid electrolyte interface (SEI) by rolling with the organic phosphating lubricant. The obtained phosphating interface with high surface energy and surface Young’s modulus significantly induces the dense deposition of Li+ and results in a stable cycling. The phosphating interface enables the symmetric cells to cycle stably for 750 h at 1 mA cm−2 with 1 mA h cm−2 and for 450 h at 3 mA cm−2 with 3 mA h cm−2 using ester-based electrolyte. The full cell with high single-side mass loading (10 mg cm−2) of LiCoO2 achieves a capacity retention rate of 77.7 % after 165 cycles at 1 C and 75.6 % after 120 cycles at 2 C. This work paves a path to construct a green fluorine-free interface and provide a large-scale modification for practical lithium strips.