Highly reversible Zn metal anode enabled by sustainable hydroxyl chemistry.

Rechargeable Zn metal batteries (RZMBs) may provide a more sustainable and lower-cost alternative to established battery technologies in meeting energy storage applications of the future. However, the most promising electrolytes for RZMBs are generally aqueous and require high concentrations of salt(s) to bring efficiencies toward commercially viable levels and mitigate water-originated parasitic reactions including hydrogen evolution and corrosion. Electrolytes based on nonaqueous solvents are promising for avoiding these issues, but full cell performance demonstrations with solvents other than water have been very limited. To address these challenges, we investigated MeOH as an alternative electrolyte solvent. These MeOH-based electrolytes exhibited exceptional Zn reversibility over a wide temperature range, with a Coulombic efficiency > 99.5% at 50% Zn utilization without cell short-circuit behavior for > 1,800 h. More important, this remarkable performance translates well to Zn || metal-free organic cathode full cells, supporting < 6% capacity decay after > 800 cycles at -40 °C.

Extending Ring-Chain Coupling Empirical Law to Lithium-Mediated Electrochemical Ammonia Synthesis.

With its efficient nitrogen fixation kinetics, electrochemical lithium-mediated nitrogen reduction reaction (LMNRR) holds promise for replacing Haber-Bosch process and realizing sustainable and green ammonia production. However, the general interface problem in lithium electrochemistry seriously impedes the further enhancement of LMNRR performance. Inspired by the development history of lithium battery electrolytes, here, we extend the ring-chain solvents coupling law to LMNRR system to rationally optimize the interface during the reaction process, achieving nearly a two-fold Faradaic efficiency up to 54.78±1.60 %. Systematic theoretical simulations and experimental analysis jointly decipher that the anion-rich Li+ solvation structure derived from ring tetrahydrofuran coupling with chain ether successfully suppresses the excessive passivation of electrolyte decomposition at the reaction interface, thus promoting the mass transfer of active species and enhancing the nitrogen fixation kinetics. This work offers a progressive insight into the electrolyte design of LMNRR system.

Leveraging Ion Pairing and Transport in Localized High-Concentration Electrolytes for Reversible Lithium Metal Anodes at Low Temperatures.

Coulombic efficiency of over 99% is rarely achieved for Li metal anode below -40°C, hindering the practical application of high-energy-density Li metal batteries under extreme conditions. Herein, limiting factors for Li metal reversibility are investigated utilizing ether-based localized high-concentration electrolytes of different solvent-diluent combinations. We find that along with the desolvation barrier, bulk ion transport properties including ionic conductivity, transference number, and diffusivity are also crucial factors for low-temperature Li deposition behavior. Superior Li metal reversibility was observed within the combination of the solvent with moderately weak solvating power and the diluent with minimal viscosity, highlighting the role of ion transport and the necessity for a trade-off with desolvation. The optimized electrolyte composed of lithium bis(fluorosulfonyl)imide, methyl n-propyl ether, and 1,1,2,2-tetrafluoroethyl methyl ether delivers exceptional Coulombic efficiency of 99.34% at -40°C and 98.96% at -60°C under a current density of 0.5 mA cm-2. Furthermore, Li||LiCoO2 (2.7 mAh cm-2) cells demonstrate impressive reversible capacity and cycling stability at these temperatures. This work sheds light on the less-recognized relevance of bulk ion transport to low-temperature performance and provides guidelines for the electrolyte design of Li metal batteries operating in cold environments.

Reduction-Tolerance Electrolyte Design for High-Energy Lithium Batteries.

Lithium batteries employing Li or silicon (Si) anodes hold promise for the next-generation energy storage systems. However, their cycling behavior encounters rapid capacity degradation due to the vulnerability of solid electrolyte interphases (SEIs). Though anion-derived SEIs mitigate this degradation, the unavoidable reduction of solvents introduces heterogeneity to SEIs, leading to fractures during cycling. Here, we elucidate how the reductive stability of solvents, dominated by the electrophilicity (EPT) and coordination ability (CDA), delineates the SEI formed on Li or Si anodes. Solvents exhibiting lower EPT and CDA demonstrate enhanced tolerance to reduction, resulting in inorganic-rich SEIs with homogeneity. Guided by these criteria, we synthesized three promising solvents tailored for Li or Si anodes. The decomposition of these solvents is dictated by their EPTs under similar solvation structures, imparting distinct characteristics to SEIs and impacting battery performance. The optimized electrolyte, 1 M lithium bis(fluorosulfonyl)imide (LiFSI) in N-Pyrrolidine-trifluoromethanesulfonamide (TFSPY), achieves 600 cycles of Si anodes with a capacity retention of 81 % (1910 mAh g-1). In anode-free Cu||LiNi0.5Co0.2Mn0.3O2 (NCM523) pouch cells, this electrolyte sustains over 100 cycles with an 82 % capacity retention. These findings illustrate that reducing solvent decomposition benefits SEI formation, offering valuable insights for the designing electrolytes in high-energy lithium batteries.

Simultaneous High Ionic Conductivity and Lithium-Ion Transference Number in Single-Ion Conductor Network Polymer Enabling Fast-Charging Solid-State Lithium Battery.

Developing solid-state electrolyte with sufficient ionic conduction and flexible-intimate interface is vital to advance fast-charging solid-state lithium batteries. Solid polymer electrolyte yields the promise of interfacial compatibility, yet its critical bottleneck is how to simultaneously achieve high ionic conductivity and lithium-ion transference number. Herein, single-ion conducting network polymer electrolyte (SICNP) enabling fast charging is proposed to positively realize fast lithium-ion locomotion with both high ionic conductivity of 1.1 × 10-3 S cm-1 and lithium-ion transference number of 0.92 at room temperature. Experimental characterization and theoretical simulations demonstrate that the construction of polymer network structure for single-ion conductor not only facilitates fast hopping of lithium ions for boosting ionic kinetics, but also enables a high dissociation level of the negative charge for lithium-ion transference number close to unity. As a result, the solid-state lithium batteries constructed by coupling SICNP with lithium anodes and various cathodes (e.g., LiFePO4 , sulfur, and LiCoO2 ) display impressive high-rate cycling performance (e.g., 95% capacity retention at 5 C for 1000 cycles in LiFePO4 |SICNP|lithium cell) and fast-charging capability (e.g., being charged within 6 min and discharged over than 180 min in LiCoO2 |SICNP|lithium cell). Our study provides a prospective direction for solid-state electrolyte that meets the lithium-ion dynamics for practical fast-charging solid-state lithium batteries.

Electrolyte Engineering Enables High Performance Zinc-Ion Batteries.

Zinc-ion batteries (ZIBs) feature high safety, low cost, environmental-friendliness, and promising electrochemical performance, and are therefore regarded as a potential technology to be applied in large-scale energy storage devices. However, ZIBs still face some critical challenges and bottlenecks. The electrolyte is an essential component of batteries and its properties affect the mass transport, energy storage mechanisms, reaction kinetics, and side reactions of ZIBs. The adjustment of electrolyte formulas usually has direct and obvious impacts on the overall output and performance. In this review, advanced electrolyte strategies are overviewed for optimizing the compatibility between cathode materials and electrolytes, inhibiting anode corrosion and dendrite growth, extending electrochemical stability windows, enabling wearable applications, and enhancing temperature tolerance. The underlying scientific mechanisms, electrolyte design principles, and recent progress are presented to provide a better understanding and inspiration to readers. In addition, a comprehensive perspective about electrolyte design and engineering for ZIBs is included.

Advanced Electrolyte Design for High-Energy-Density Li-Metal Batteries under Practical Conditions.

Given the limitations inherent in current intercalation-based Li-ion batteries, much research attention has focused on potential successors to Li-ion batteries such as lithium-sulfur (Li-S) batteries and lithium-oxygen (Li-O2 ) batteries. In order to realize the potential of these batteries, the use of metallic lithium as the anode is essential. However, there are severe safety hazards associated with the growth of Li dendrites, and the formation of "dead Li" during cycles leads to the inevitable loss of active Li, which in the end is undoubtedly detrimental to the actual energy density of Li-metal batteries. For Li-metal batteries under practical conditions, a low negative/positive ratio (N/P ratio), a electrolyte/cathode ratio (E/C ratio) along with a high-voltage cathode is prerequisite. In this Review, we summarize the development of new electrolyte systems for Li-metal batteries under practical conditions, revisit the design criteria of advanced electrolytes for practical Li-metal batteries and provide perspectives on future development of electrolytes for practical Li-metal batteries.

Predicting the Solubility of Sulfur: A COSMO-RS-Based Approach to Investigate Electrolytes for Li-S Batteries.

Lithium-sulfur (Li-S) batteries are, in theory, considering their basic reactions, very promising from a specific energy density point of view, but have poor power rate capabilities. The dissolution of sulfur from the C/S cathode in the electrolyte is a rate-determining and crucial step for the functionality. To date, time-consuming experimental methods, such as HPLC/UV, have been used to quantify the corresponding solubilities. Here, we use a computational fluid-phase thermodynamics approach, the conductor-like screening model for real solvents (COSMO-RS), to compute the solubilities of sulfur in different binary and ternary electrolytes. By using both explicit and implicit solvation approaches for lithium bistrifluoromethanesulfonimidate (LiTFSI)-containing electrolytes, a deviation of <0.4 log units was achieved with respect to experimental data, within the range of experimental error, thus proving COSMO-RS to be a useful tool for exploring novel Li-S battery electrolytes.

Revealing the Anion-Solvent Interaction for Ultralow Temperature Lithium Metal Batteries.

Anion solvation in electrolytes can largely change the electrochemical performance of the electrolytes, yet has been rarely investigated. Herein, three anions of bis(trifluoromethanesulfonyl)imide (TFSI), bis(fluorosulfonyl)imide (FSI), and derived asymmetric (fluorosulfonyl)(trifluoro-methanesulfonyl)imide (FTFSI) are systematically examined in a weakly Li+ cation solvating solvent of bis(3-fluoropropyl)ether (BFPE). In-situ liquid secondary ion mass spectrometry demonstrates that FTFSI- and FSI- anions are associated with BFPE solvent, while weak TFSI- /BFPE cluster signals are detected. Molecular modeling further reveals that the anion-solvent interaction is accompanied by the formation of H-bonding-like interactions. Anion solvation enhances the Li+ cation transfer number and reduces the organic component in solid electrolyte interphase, which enhances the Li plating/stripping Coulombic efficiency at a low temperature of -30 °C from 42.4% in TFSI-based electrolytes to 98.7% in 1.5 m LiFTFSI and 97.9% in LiFSI-BFPE electrolytes. The anion-solvent interactions, especially asymmetric anion solvation also accelerate the Li+ desolvation kinetics. The 1.5 m LiFTFSI-BFPE electrolyte with strong anion-solvent interaction enables LiNi0.8 Mn0.1 Co0.1 O2 (NMC811)||Li (20 µm) full cell with stable cyclability even under -40 °C, retaining over 92% of initial capacity (115 mAh g-1 , after 100 cycles). The anion-solvent interactions insights allow to rational design the electrolyte for lithium metal batteries and beyond to achieve high performance.

Intrinsically Safe Lithium Metal Batteries Enabled by Thermo-Electrochemical Compatible In Situ Polymerized Solid-State Electrolytes.

In situ polymerized solid-state electrolytes have attracted much attention due to high Li-ion conductivity, conformal interface contact, and low interface resistance, but are plagued by lithium dendrite, interface degradation, and inferior thermal stability, which thereby leads to limited lifespan and severe safety hazards for high-energy lithium metal batteries (LMBs). Herein, an in situ polymerized electrolyte is proposed by copolymerization of 1,3-dioxolane with 1,3,5-tri glycidyl isocyanurate (TGIC) as a cross-linking agent, which realizes a synergy of battery thermal safety and interface compatibility with Li anode. Functional TGIC enhances the electrolyte polymeric level. The unique carbon-formation mechanism facilitates flame retardancy and eliminates the battery fire risk. In the meantime, TGIC-derived inorganic-rich interphase inhibits interface side reactions and promotes uniform Li plating. Intrinsically safe LMBs with nonflammability and outstanding electrochemical performances under extreme temperatures (130 °C) are achieved. This functional polymer design shows a promising prospect for the development of safe LMBs.

N-Rich Bilayer Solid Electrolyte Interphase toward Highly Reversible Lithium Metal Batteries.

Continuous lithium (Li)/electrolyte interfacial reactions and uncontrollable Li dendrites severely hamper the application of paradigmatic Li metal batteries (LMBs). Aiming to address the above-mentioned crucial issues, N-rich polymer-inorganic bilayers at the Li/electrolyte interface are designed via nitrate-rich electrolytes, achieving high-energy-density and long-lifespan LMBs. The inner layer of Li3N favors rapid and uniform Li+ deposition, while the outer layer of N-containing flexible polymers facilitates uniform Li+ distribution at the interlayer and accommodates volume changes during cycling. The synergistic effect of N-rich polymer-inorganic bilayers promotes the formation of dense uniform spherical nuclei morphology instead of dendrites, thus significantly improving the plating-stripping reversibility of LMBs. Attributed to the unique interphase, the Li|Li cell can stably run for over 1000 h at 1.0 mA cm-2 with an even deposition morphology, which is monitored and proven by in situ optical microscopy. Moreover, the assembled Li|S cell displays a high capacity of 697.6 mA h g-1 for over 150 cycles and a 99% Coulombic efficiency. This work paves the way for designing high-energy and long-lifespan LMBs.

Wide Temperature Electrolytes for Lithium Batteries: Solvation Chemistry and Interfacial Reactions.

Improving the wide-temperature operation of rechargeable batteries is crucial for boosting the adoption of electric vehicles and further advancing their application scope in harsh environments like deep ocean and space probes. Herein, recent advances in electrolyte solvation chemistry are critically summarized, aiming to address the long-standing challenge of notable energy diminution at sub-zero temperatures and rapid capacity degradation at elevated temperatures (>45°C). This review provides an in-depth analysis of the fundamental mechanisms governing the Li-ion transport process, illustrating how these insights have been effectively harnessed to synergize with high-capacity, high-rate electrodes. Another critical part highlights the interplay between solvation chemistry and interfacial reactions, as well as the stability of the resultant interphases, particularly in batteries employing ultrahigh-nickel layered oxides as cathodes and high-capacity Li/Si materials as anodes. The detailed examination reveals how these factors are pivotal in mitigating the rapid capacity fade, thereby ensuring a long cycle life, superior rate capability, and consistent high-/low-temperature performance. In the latter part, a comprehensive summary of in situ/operational analysis is presented. This holistic approach, encompassing innovative electrolyte design, interphase regulation, and advanced characterization, offers a comprehensive roadmap for advancing battery technology in extreme environmental conditions.

Massively Reconstructing Hydrogen Bonding Network and Coordination Structure Enabled by a Natural Multifunctional Co-Solvent for Practical Aqueous Zn-Ion Batteries.

The practical application of aqueous Zn-ion batteries (AZIBs) is hindered by the crazy Zn dendrites growth and the H2O-induced side reactions, which rapidly consume the Zn anode and H2O molecules, especially under the lean electrolyte and Zn anode. Herein, a natural disaccharide, d-trehalose (DT), is exploited as a novel multifunctional co-solvent to address the above issues. Molecular dynamics simulations and spectral characterizations demonstrate that DT with abundant polar -OH groups can form strong interactions with Zn2+ ions and H2O molecules, and thus massively reconstruct the coordination structure of Zn2+ ions and the hydrogen bonding network of the electrolyte. Especially, the strong H-bonds between DT and H2O molecules can not only effectively suppress the H2O activity but also prevent the rearrangement of H2O molecules at low temperature. Consequently, the AZIBs using DT30 electrolyte can show high cycling stability even under lean electrolyte (E/C ratio = 2.95 µL mAh-1), low N/P ratio (3.4), and low temperature (-12 °C). As a proof-of-concept, a Zn||LiFePO4 pack with LiFePO4 loading as high as 506.49 mg can be achieved. Therefore, DT as an eco-friendly multifunctional co-solvent provides a sustainable and effective strategy for the practical application of AZIBs.

Rational Molecular Engineering via Electron Reconfiguration toward Robust Dual-Electrode/Electrolyte Interphases for High-Performance Lithium Metal Batteries.

High-energy-density lithium-metal batteries (LMBs) coupling lithium-metal anodes and high-voltage cathodes are hindered by unstable electrode/electrolyte interphases (EEIs), which calls for the rational design of efficient additives. Herein, we analyze the effect of electron structure on the coordination ability and energy levels of the additive, from the aspects of intramolecular electron cloud density and electron delocalization, to reveal its mechanism on solvation structure, redox stability, as-formed EEI chemistry, and electrochemical performances. Furthermore, we propose an electron reconfiguration strategy for molecular engineering of additives, by taking sorbide nitrate (SN) additive as an example. The lone pair electron-rich group enables strong interaction with the Li ion to regulate solvation structure, and intramolecular electron delocalization yields further positive synergistic effects. The strong electron-withdrawing nitrate moiety decreases the electron cloud density of the ether-based backbone, improving the overall oxidation stability and cathode compatibility, anchoring it as a reliable cathode/electrolyte interface (CEI) framework for cathode integrity. In turn, the electron-donating bicyclic-ring-ether backbone breaks the inherent resonance structure of nitrate, facilitating its reducibility to form a N-contained and inorganic Li2O-rich solid electrolyte interface (SEI) for uniform Li deposition. Optimized physicochemical properties and interfacial biaffinity enable significantly improved electrochemical performance. High rate (10 C), low temperature (-25 °C), and long-term stability (2700 h) are achieved, and a 4.5 Ah level Li||NCM811 multilayer pouch cell under harsh conditions is realized with high energy density (462 W h/kg). The proof of concept of this work highlights that the rational ingenious molecular design based on electron structure regulation represents an energetic strategy to modulate the electrolyte and interphase stability, providing a realistic reference for electrolyte innovations and practical LMBs.

Electrolyte Design for Lithium-Ion Batteries for Extreme Temperature Applications.

With increasing energy storage demands across various applications, reliable batteries capable of performing in harsh environments, such as extreme temperatures, are crucial. However, current lithium-ion batteries (LIBs) exhibit limitations in both low and high-temperature performance, restricting their use in critical fields like defense, military, and aerospace. These challenges stem from the narrow operational temperature range and safety concerns of existing electrolyte systems. To enable LIBs to function effectively under extreme temperatures, the optimization and design of novel electrolytes are essential. Given the urgency for LIBs operating in extreme temperatures and the notable progress in this research field, a comprehensive and timely review is imperative. This article presents an overview of challenges associated with extreme temperature applications and strategies used to design electrolytes with enhanced performance. Additionally, the significance of understanding underlying electrolyte behavior mechanisms and the role of different electrolyte components in determining battery performance are emphasized. Last, future research directions and perspectives on electrolyte design for LIBs under extreme temperatures are discussed. Overall, this article offers valuable insights into the development of electrolytes for LIBs capable of reliable operation in extreme conditions.

Mixed-Anion Contact Ion-Pair Formation Enabling Improved Performance of Halide-Free Mg-Ion Electrolytes.

Discovery of stable and efficient electrolytes that are compatible with magnesium metal anodes and high-voltage cathodes is crucial to enabling energy storage technologies that can move beyond existing Li-ion systems. Many promising electrolytes for magnesium anodes have been proposed with chloride-based systems at the forefront; however, Cl-containing electrolytes lack the oxidative stability required by high-voltage cathodes. In this work, we report magnesium trifluoromethanesulfonate (triflate) as a viable coanion for Cl-free, mixed-anion magnesium electrolytes. The addition of triflate to electrolytes containing bis(trifluoromethane sulfonyl) imide (TFSI-) anions yields significantly improved Coulombic efficiency, up to a 100 mV decrease in the plating/stripping overpotential, improved tolerance to trace H2O, and improved oxidative stability (0.35 V improvement compared to that of hybrid TFSI-Cl electrolytes). Based on 19F nuclear magnetic resonance and Raman spectroscopy measurements, we propose that these improvements in performance are driven by the formation of mixed-anion contact ion pairs, where both triflate and TFSI- are coordinated to Mg2+ in the electrolyte bulk. The formation of this mixed-anion magnesium complex is further predicted by the density functional theory to be thermodynamically driven. Collectively, this work outlines the guiding principles for the improved design of next-generation electrolytes for magnesium batteries.

Organic Thin Films Enable Retaining the Oxidation State of Copper Catalysts during CO2 Electroreduction.

A key challenge in electrocatalysis remains controlling a catalyst's structural, chemical, and electrical properties under reaction conditions. While organic coatings showed promise for enhancing the selectivity and stability of catalysts for CO2 electroreduction (CO2RR), their impact on the chemical state of underlying metal electrodes has remained unclear. In this study, we show that organic thin films on polycrystalline copper (Cu) enable retaining Cu+ species at reducing potentials down to -1.0 V vs RHE, as evidenced by operando Raman and quasi in situ X-ray photoelectron spectroscopy. In situ electrochemical atomic force microscopy revealed the integrity of the porous organic film and nearly unaltered Cu electrode morphology. While the pristine thin film enhances the CO2-to-ethylene conversion, the addition of organic modifiers into electrolytes gives rise to improved CO2RR performance stability. Our findings showcase hybrid metal-organic systems as a versatile approach to control, beyond morphology and local environment, the oxidation states of catalysts and energy conversion materials.

Demystifying the Salt-Induced Li Loss: A Universal Procedure for the Electrolyte Design of Lithium-Metal Batteries.

Lithium (Li) metal electrodes show significantly different reversibility in the electrolytes with different salts. However, the understanding on how the salts impact on the Li loss remains unclear. Herein, using the electrolytes with different salts (e.g., lithium hexafluorophosphate (LiPF6), lithium difluoro(oxalato)borate (LiDFOB), and lithium bis(fluorosulfonyl)amide (LiFSI)) as examples, we decouple the irreversible Li loss (SEI Li+ and "dead" Li) during cycling. It is found that the accumulation of both SEI Li+ and "dead" Li may be responsible to the irreversible Li loss for the Li metal in the electrolyte with LiPF6 salt. While for the electrolytes with LiDFOB and LiFSI salts, the accumulation of "dead" Li predominates the Li loss. We also demonstrate that lithium nitrate and fluoroethylene carbonate additives could, respectively, function as the "dead" Li and SEI Li+ inhibitors. Inspired by the above understandings, we propose a universal procedure for the electrolyte design of Li metal batteries (LMBs): (i) decouple and find the main reason for the irreversible Li loss; (ii) add the corresponding electrolyte additive. With such a Li-loss-targeted strategy, the Li reversibility was significantly enhanced in the electrolytes with 1,2-dimethoxyethane, triethyl phosphate, and tetrahydrofuran solvents. Our strategy may broaden the scope of electrolyte design toward practical LMBs.

Electrolyte Design for Low-Temperature Li-Metal Batteries: Challenges and Prospects.

Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation. To get the most energy storage out of the battery at low temperatures, improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases. Herein, this review critically outlines electrolytes' limiting factors, including reduced ionic conductivity, large de-solvation energy, sluggish charge transfer, and slow Li-ion transportation across the electrolyte/electrode interphases, which affect the low-temperature performance of Li-metal batteries. Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding. Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared. Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries.

Potassium 2-thienyl tri-fluoroborate as a functional electrolyte additive enables stable interfaces for Li/LiFe0.3Mn0.7PO4batteries.

As a promising cathode material for high-performance lithium-ion batteries, olivine LiFe1-xMnxPO4 (0 < x < 1, LFMP) combines the high safety of LiFePO4 and the high energy density of LiMnPO4. During the charge-discharge process, poor interface stability of active materials leads to capacity decay, which prevents its commercial application. Here, to stabilize the interface, a new electrolyte additive potassium 2-thienyl tri-fluoroborate (2-TFBP) is developed to boost the performance of LiFe0.3Mn0.7PO4 at 4.5 V vs. Li/Li+. Specifically, after 200 cycles, the capacity retention remains at 83.78% in the electrolyte containing 0.2% 2-TFBP while the capacity retention without 2-TFBP addition is only 53.94%. Based on the comprehensive measurements results, the improved cyclic performance is attributed to that 2-TFBP has a higher highest occupied molecular orbit (HOMO) energy and its thiophene group can be electropolymerized above 4.4 V vs. Li/Li+ for generating uniform cathode electrolyte interphase (CEI) with poly-thiophene, which can stable materials structure and suppress the decomposition of electrolytes. Meanwhile, 2-TFBP both promotes the deposition/exfoliation of Li+ at anode-electrolyte interfaces and regulates Li deposition by K+ cations through the electrostatic mechanism. This work presents that 2-TFBP has a great application prospect as a functional additive for high-voltage and high-energy-density lithium metal batteries.