Dual‐Function Presodiation with Sodium Diphenyl Ketone towards Ultra‐stable Hard Carbon Anodes for Sodium‐Ion Batteries

Angewandte Chemie International Edition, Год журнала: 2022, Номер 62(2)

Опубликована: Ноя. 12, 2022

Hard carbon (HC) is a promising anode material for sodium-ion batteries, yet still suffers from low initial Coulombic efficiency (ICE) and unstable solid electrolyte interphase (SEI). Herein, sodium diphenyl ketone (Na-DK) applied to realize dual-function presodiation HC anodes. It compensates the irreversible Na uptake at oxygen-containing functional groups reacts with defects of five/seven-membered rings quasi-metallic in HC. The as-formed induces robust NaF-rich SEI on 1.0 M NaPF6 diglyme, favoring interfacial reaction kinetics stable Na+ insertion extraction. This renders presodiated (pHC) high ICE ≈100 % capacity retention 82.4 after 6800 cycles. demonstrated couple Na3 V2 (PO4 )3 cathodes full cells show 700 work provides in-depth understanding chemical new strategy highly batteries.

Язык: Английский

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Weakly Solvating Cyclic Ether Electrolyte for High-Voltage Lithium Metal Batteries

ACS Energy Letters, Год журнала: 2023, Номер 8(4), С. 1752 - 1761

Опубликована: Март 13, 2023

The commercialization of high-voltage lithium (Li) metal batteries (LMBs) has been severely hindered due to the lack advanced electrolytes that can simultaneously support a stable anode (LMA) and cathode (>4 V vs Li+/Li). Here, we propose tetrahydropyran (THP)-based weakly solvating electrolyte (WSE) regulate Li+ solvation structures interfacial behaviors. anion-rich in THP-based WSE effectively promotes formation inorganic-rich solid interphase (SEI) layers, firm (CEI) films, protective passivation films on an Al current collector. optimized behaviors contribute highly compact Li deposition, stability, inhibition transition ion dissolution corrosion. Finally, Li||LiNi0.5Co0.2Mn0.3O2 full cell delivered cycling performance at high cutoff voltages 4.3 even 4.5 V. This study demonstrates exciting approach enable ether-based for LMBs could be developed other battery systems.

Язык: Английский

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Optimizing NaF‐Rich Solid Electrolyte Interphase for Stabilizing Sodium Metal Batteries by Electrolyte Additive

Advanced Functional Materials, Год журнала: 2023, Номер 34(5)

Опубликована: Апрель 27, 2023

Abstract NaF‐rich electrode–electrolyte interphases play crucial roles in determining the cycling stability of sodium metal batteries (SMBs) because their electronic insulation and mechanical stability. In this work, perfluorobenzene (PFB) is proposed as additive to contribute formation solid electrolyte (SEI). PFB at periphery solvation layer can pull out a part EC with lowest energy by Van der Waals forces, thus allowing more participate Na + form an anion‐aggregated sheath, promoting decomposition produce NaF. addition, has higher highest occupied molecular orbital lower unoccupied level, which also preferentially decomposes NaF both electrodes. Benefiting from intensified ratio SEI, Na||Na symmetric cells such achieves superior life over 350 h 1 mA cm −2 , 3 V 2 (PO 4 ) O F realize ultrahigh performance 88.8% capacity retention after 500 cycles.

Язык: Английский

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Highly Reversible Zinc Metal Anodes Enabled by Solvation Structure and Interface Chemistry Modulation

Advanced Energy Materials, Год журнала: 2023, Номер 13(36)

Опубликована: Авг. 9, 2023

Abstract Aqueous Zn−ion batteries (AZIBs) promise appealing advantages including safety, affordability, and high volumetric energy density. However, rampant parasitic reactions dendrite growth result in inadequate Zn reversibility. Here, a biocompatible additive, L‐asparagine (Asp), low‐cost aqueous electrolyte, is introduced to address these concerns. Combining substantive verification tests theoretical calculations, it demonstrated that an Asp‐containing ZnSO 4 electrolyte can create robust nanostructured solid‐electrolyte interface (SEI) by simultaneously modulating the 2+ solvation structure optimizing metal‐molecule interface, which enables dense deposition. The optimized supports excellent reversibility achieving dendrite‐free plating/stripping over 240 h at utilization of 85.5% symmetrical cell average 99.6% Coulombic efficiency for 1600 cycles asymmetrical cell. Adequate full‐cell performance with poly(3,4‐ethylenedioxythiophene) intercalated vanadium oxide (PEDOT‐V 2 O 5 ) cathode, delivers areal capacity 4.62 mAh cm −2 holds 84.4% retention 200 under practical conditions ultrathin anode (20 µm) low negative/positive ratio (≈2.4). This engineering strategy provides new insights into regulating anode/electrolyte interfacial chemistries toward high‐performance AZIBs.

Язык: Английский

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Synergetic modulation on ionic association and solvation structure by electron-withdrawing effect for aqueous zinc-ion batteries

Proceedings of the National Academy of Sciences, Год журнала: 2023, Номер 120(15)

Опубликована: Апрель 6, 2023

Aqueous zinc-ion batteries are emerging as one of the most promising large-scale energy storage systems due to their low cost and high safety. However, Zn anodes often encounter problems dendrite growth, hydrogen evolution reaction, formation by-products. Herein, we developed ionic association electrolytes (LIAEs) by introducing 2, 2-trifluoroethanol (TFE) into 30 m ZnCl 2 electrolyte. Owing electron-withdrawing effect -CF 3 groups in TFE molecules, LIAEs, 2+ solvation structures convert from larger aggregate clusters smaller parts will construct H-bonds with H O structure simultaneously. Consequently, migration kinetics significantly enhanced ionization solvated is effectively suppressed LIAEs. As a result, LIAE display fast plating/stripping Coulombic efficiency 99.74%. The corresponding full exhibit an improved comprehensive performance such high-rate capability long cycling life.

Язык: Английский

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Correlating the Solvating Power of Solvents with the Strength of Ion‐Dipole Interaction in Electrolytes of Lithium‐ion Batteries

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(47)

Опубликована: Окт. 9, 2023

The solvation structure of Li+ plays a significant role in determining the physicochemical properties electrolytes. However, to date, there is still no clear definition solvating power different electrolyte solvents, and even solvents that preferentially participate remain controversial. In this study, we comprehensively discuss process ions using both experimental characterizations theoretical calculations. Our findings reveal dependent on strength -solvent (ion-dipole) interaction. Additionally, uncover anions tend enter sheath most systems through -anion (ion-ion) interaction, which weakened by shielding effect solvents. competition between interactions ultimately determines final structures. This insight into fundamental understanding provides inspiration for design multifunctional mixed-solvent electrolytes advanced batteries.

Язык: Английский

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Space‐Confined Guest Synthesis to Fabricate Sn‐Monodispersed N‐Doped Mesoporous Host toward Anode‐Free Na Batteries

Advanced Materials, Год журнала: 2023, Номер 35(32)

Опубликована: Май 11, 2023

Severe issues including volume change and dendrite growth on sodium metal anodes hinder the pursuit of applicable high-energy-density batteries. Herein, an in situ reaction approach is developed that takes metal-organic frameworks as nano-reactor pore-former to produce a mesoporous host comprised nitrogen-doped carbon fibers embedded with monodispersed Sn clusters (SnNCNFs). The hybrid shows outstanding sodiophilicity enables rapid Na infusion ultralow nucleation overpotential 2 mV. Its porous structure holds high content guides uniform deposition. Such provides favorable plating/stripping average Coulombic efficiency 99.96% over 2000 cycles (at 3 mA cm-2 h ). Na-infused SnNCNF anode delivers extreme utilization 86% symmetric cells 10 ), rate capability cycle life Na-SnNCNF||Na3 V2 (PO4 )3 full 1 A g-1 for 1000 capacity retention 92.1%). Furthermore, high-energy/power-density anode-less anode-free are achieved. This work presents effective heteroatom-doping fabricating multifunctional materials developing high-performance

Язык: Английский

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Solvent versus Anion Chemistry: Unveiling the Structure-Dependent Reactivity in Tailoring Electrochemical Interphases for Lithium-Metal Batteries

JACS Au, Год журнала: 2023, Номер 3(3), С. 953 - 963

Опубликована: Фев. 17, 2023

Electrolytes are critical for the reversibility of various electrochemical energy storage systems. The recent development electrolytes high-voltage Li-metal batteries has been counting on salt anion chemistry building stable interphases. Herein, we investigate effect solvent structure interfacial reactivity and discover profound designed monofluoro-ether in anion-enriched solvation structures, which enables enhanced stabilization both cathodes anodes. Systematic comparison different molecular derivatives provides an atomic-scale understanding unique structure-dependent reactivity. interaction between Li+ monofluoro (-CH2F) group significantly influences electrolyte promotes monofluoro-ether-based reactions over chemistry. With in-depth analyses compositions, charge transfer, ion transport at interfaces, demonstrated essential role tailoring highly protective conductive interphases (with enriched LiF full depths) electrodes, as opposed to anion-derived ones typical concentrated electrolytes. As a result, solvent-dominant high Li Coulombic efficiency (∼99.4%) anode cycling rate (10 mA cm-2), together with greatly improved stability 4.7 V-class nickel-rich cathodes. This work illustrates underlying mechanism competitive reaction schemes offers fundamental insights into rational design future high-energy batteries.

Язык: Английский

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Electrolytes with Solvating Inner Sheath Engineering for Practical Na–S Batteries

Advanced Materials, Год журнала: 2023, Номер 35(24)

Опубликована: Март 16, 2023

Sodium-sulfur (Na-S) batteries with durable Na-metal stability, shuttle-free cyclability, and long lifespan are promising to large-scale energy storages. However, meeting these stringent requirements poses huge challenges the existing electrolytes. Herein, a localized saturated electrolyte (LSE) is proposed 2-methyltetrahydrofuran (MeTHF) as an inner sheath solvent, which represents new category of for Na-S system. Unlike traditional high concentration electrolytes, LSE realized low salt-to-solvent ratio diluent-to-solvent ratio, pushes limit (LHCE). The appropriate molecular structure solvation ability MeTHF regulate sheath, features reinforced coordination Na+ anions, enlarged -solvent distance, weakened anion-diluent interaction. Such configuration found be key build sustainable interphase quasi-solid-solid sulfur redox process, making dendrite-inhibited battery possible. With this electrolyte, pouch cells decent cycling performance under rather demanding conditions demonstrated.

Язык: Английский

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Regulation of anion–Na ⁺ coordination chemistry in electrolyte solvates for low-temperature sodium-ion batteries

Proceedings of the National Academy of Sciences, Год журнала: 2024, Номер 121(5)

Опубликована: Янв. 22, 2024

High-performance sodium storage at low temperature is urgent with the increasingly stringent demand for energy systems. However, aggravated capacity loss induced by sluggish interfacial kinetics, which originates from Na + desolvation. Herein, all-fluorinated anions ultrahigh electron donicity, trifluoroacetate (TFA − ), are introduced into diglyme (G2)-based electrolyte anion-reinforced solvates in a wide range. The unique solvation structure TFA and decreased G2 molecules occupying inner sheath accelerates desolvation of to exhibit 4.16 3.49 kJ mol −1 24.74 16.55 beyond below −20 °C, respectively, compared that 1.0 M NaPF 6 -G2. These enable cell Na||Na 3 V 2 (PO 4 ) deliver 60.2% its room-temperature high retention 99.2% after 100 cycles −40 °C. This work highlights regulation chemistry highly stable sodium-ion batteries temperature.

Язык: Английский

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