Additive‐guided Solvation‐regulated Flame‐retardant Electrolyte Enables High‐voltage Lithium Metal Batteries with Robust Electrode Electrolyte Interphases

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(16)

Published: Jan. 2, 2024

Abstract Widening the voltage window of nickel‐rich layered oxide cathode‐based lithium metal batteries (LMBs) can effectively improve energy density rechargeable batteries. However, serious safety issues associated with high reactivity between LiNi 0.8 Co 0.1 Mn O 2 (NCM811) and electrolyte at cut‐off remains challenging. Herein, a flame‐retardant ability to form robust armor‐like electrode interphase (EEI) LiF Li x B y z compounds for stabilizing Li||NCM811 is proposed. Such exhibits thermal stability effect ensuring battery voltage. The EEI protect both NCM811 (Li) improving cycling performance. As result, capacity retention rate cathode such reached 68% after 150 cycles 4.6 V. This work provides an effective reference reasonable design high‐voltage, electrolytes LMBs.

Language: Английский

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Visualizing and Regulating Dynamic Evolution of Interfacial Electrolyte Configuration during De‐solvation Process on Lithium‐Metal Anode

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(17)

Published: March 5, 2024

Abstract Acting as a passive protective layer, solid‐electrolyte interphase (SEI) plays crucial role in maintaining the stability of Li‐metal anode. Derived from reductive decomposition electrolytes (e.g., anion and solvent), SEI construction presents an interfacial process accompanied by dynamic de‐solvation during plating. However, typical electrolyte engineering related modification strategies always ignore evolution configuration at Li/electrolyte interface, which essentially determines architecture. Herein, employing advanced electrochemical situ FT‐IR MRI technologies, we directly visualize variations solvation environments involving Li + ‐solvent/anion. Remarkably, weakened ‐solvent interaction anion‐lean have been synchronously revealed, is difficult for fabrication anion‐derived layer. Moreover, simple regulation strategy, pulse protocol was introduced to effectively restore concentration, resulting enhanced LiF‐rich layer improved plating/stripping reversibility.

Language: Английский

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570 Wh kg⁻¹‐Grade Lithium Metal Pouch Cell with 4.9V Highly Li⁺ Conductive Armor‐Like Cathode Electrolyte Interphase via Partially Fluorinated Electrolyte Engineering

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(24)

Published: March 4, 2024

Abstract Lithium‐rich manganese‐based layered oxides (LRMOs) are promisingly used in high‐energy lithium metal pouch cells due to high specific capacity/working voltage. However, the interfacial stability of LRMOs remains challenging. To address this question, a novel armor‐like cathode electrolyte interphase (CEI) model is proposed for stabilizing LRMO at 4.9 V by exploring partially fluorinated formulation. The fluoroethylene carbonate (FEC) and tris (trimethylsilyl) borate (TMSB) formulated largely contribute formation CEI with LiB x O y Li PO F z outer layer LiF‐ 3 4 ‐rich inner part. Such effectively inhibits lattice oxygen loss facilitates + migration smoothly guaranteeing deliver superior cycling rate performance. As expected, Li||LRMO batteries such achieve capacity retention 85.7% average Coulomb efficiency (CE) 99.64% after 300 cycles 4.8 V/0.5 C, even obtain 87.4% 100 higher cut‐off voltage V. Meanwhile, 9 Ah‐class show over thirty‐eight stable life energy density 576 Wh kg −1

Language: Английский

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Lithium Superionic Conductive Nanofiber-Reinforcing High-Performance Polymer Electrolytes for Solid-State Batteries

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(17), P. 11897 - 11905

Published: March 28, 2024

Although composite solid-state electrolytes (CSEs) are considered promising ionic conductors for high-energy lithium metal batteries, their unsatisfactory conductivity, low mechanical strength, poor thermal stability, and narrow voltage window limit practical applications. We have prepared a new superionic conductor (Li-HA-F) with an ultralong nanofiber structure ultrahigh room-temperature conductivity (12.6 mS cm–1). When it is directly coupled typical poly(ethylene oxide)-based solid electrolyte, the Li-HA-F nanofibers endow resulting CSE high (4.0 × 10–4 S cm–1 at 30 °C), large Li+ transference number (0.66), wide (5.2 V). Detailed experiments theoretical calculations reveal that supplies continuous dual-conductive pathways results in stable LiF-rich interfaces, leading to its excellent performance. Moreover, nanofiber-reinforced exhibits good heat/flame resistance flexibility, breaking strength (9.66 MPa). As result, Li/Li half cells fabricated exhibit stability over 2000 h critical current density of 1.4 mA cm–2. Furthermore, LiFePO4/Li-HA-F CSE/Li LiNi0.8Co0.1Mn0.1O2/Li-HA-F batteries deliver reversible capacities temperature range cycling

Language: Английский

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Directing Fluorinated Solid Electrolyte Interphase by Solubilizing Crystal Lithium Fluoride in Aprotic Electrolyte for Lithium Metal Batteries

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(16)

Published: Feb. 21, 2024

Abstract Lithium fluoride (LiF) facilitates robust and fast‐ion‐transport solid electrolyte interphase (SEI) in lithium metal batteries. Fluorinated solvents/salts are ubiquitously employed to introduce LiF into SEI through electrochemical decomposition, but this approach is usually at the expense of their continuous consumption. A direct fluorinate that employs crystal limited by its poor solubility current battery formulation. Dissolving high‐dielectric‐constant solvents, like ethylene carbonate (EC) nearly neglected. Herein, feasibility directly fluorinating addition aprotic with assistance EC verified, mechanisms fluorination anti‐acidification explored. The dissolved encapsulated solvent‐/salt‐derived organic skins promote fluorinated SEI. Meanwhile, presence alters hazardous thermodynamic equilibrium, suppressing production acid species mitigate acidification degradation. Such collective benefits yield a capacity retention ratio ≈88% after 150 cycles high areal (4.5 mAh cm −2 ) Li||NCM622 cells. This facile effective contributes an in‐depth understanding formation rational design well‐performing

Language: Английский

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Hexabutylcyclohexane‐1,2,3,4,5,6‐hexaimine Additive‐Assisted Commercial Ester Electrolyte for 4.7 V Highly‐Stable Li‐Metal Batteries

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(47)

Published: Nov. 3, 2023

Abstract The development of high‐energy density batteries is utmost importance for various applications. However, the utilization numerous high‐capacity materials impeded by inadequate stability electrolytes beyond 4.5 V. This research proposes a straightforward yet highly efficient strategy to overcome this limitation and enhance interfaces in high‐voltage Li metal when employing commercial ester electrolytes. A series electrolyte additives designed with aim gradually extending length terminal alkyl groups cyclohexane‐1,2,3,4,5,6‐hexaimine (CHHI). Among these additives, hexabutylcyclohexane‐1,2,3,4,5,6‐hexaimine (HBCHHI) demonstrate exceptional performance due synergistic complementarity n‐butyl imino groups. effect leads formation thinner, denser, x N‐rich solid/cathode‐electrolyte interface. Accordingly, electrolyte‐electrode interactions are suppressed, enabling Li||LiNi 0.8 Co 0.1 Mn O 2 (NCM811) battery operation at 4.7 V alleviated structural degradation cathode even deposition anode. capacity retention Li||NCM811 cells improved ≈250% after 500 cycles rate 5C. lifespan full also prolonged quasi‐practical conditions high loading ≈2.5 mAh cm −2 .

Language: Английский

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Flame‐Retardant, Self‐Purging, High‐Voltage Electrolyte for Safe and Long‐Cycling Sodium Metal Batteries

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: June 4, 2024

Abstract Sodium metal batteries (SMBs) remain greatly challenging in safety and stability. Herein, a flame‐retardant s designed, self‐purging high‐voltage electrolyte is designed to stabilize SMBs with the use of ethoxy (pentafluoro) cyclotriphosphazene (PFPN) as additive. PFPN can participate shell structure solvation through stronger van der Waals force form Na 3 N, NaF‐rich solid/cathode interphase (SEI/CEI) electronic insulation fast ion transport. Moreover, harmful impurity (PF 5 ) also be scavenged by avoid HF production, which helps electrode interface. Additionally, combustion radicals (H, HO) cleared between radical (RPO) formed breaking for flame‐retardation purpose. As expected, Na||Na V 2 (PO 4 O F battery modified deliver reservation 92.4%, CE 99.71% after 2000 cycles, simultaneously possess excellent high‐rate charging/slow discharging performance.

Language: Английский

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Tri-anions regulated solvation structure in intrinsically nonflammable phosphate-based electrolytes for stable lithium metal batteries

Energy storage materials, Journal Year: 2024, Volume and Issue: 71, P. 103603 - 103603

Published: June 27, 2024

Language: Английский

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Recent Progress on Multifunctional Electrolyte Additives for High‐Energy‐Density Li Batteries – A Review

ChemElectroChem, Journal Year: 2024, Volume and Issue: 11(14)

Published: April 15, 2024

Abstract The improvement of the safety, specific energy, cycle life and cost reduction Li‐ion batteries are hot research topics. Now, in pursuit high energy density, employed high‐energy‐density cathode/anode materials increased operation voltage challenge prevalent electrolyte formula, like existing ester ether electrolytes cannot withstand high‐voltage high‐capacity anode such as lithium (Li), silicon (Si) silicon‐graphite (Si−C) composite anode. It is recognized that stable electrolyte‐electrode interfaces can avoid side reactions protect electrode materials. Up to now, various additives have been developed modify electrode‐electrolyte interfaces, famous 4‐fluoroethylene carbonate, vinylene carbonate nitrate, LIBs metal (LMBs) performances improved greatly. However, lifespan higher‐energy‐density with Li/Si/Si−C high‐nickel layer oxides cathode meet request due lack ideal formula. In this review, we present a comprehensive in‐depth overview on additives, especially focused multifunctional reaction mechanisms fundamental design. Finally, novel insights, promising directions potential solutions for proposed motivate Li battery chemistries.

Language: Английский

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Active Regulation Volume Change of Micrometer‐Size Li₂S Cathode with High Materials Utilization for All‐Solid‐State Li/S Batteries through an Interfacial Redox Mediator

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 34(8)

Published: Nov. 12, 2023

Abstract Low electronic and ionic transport, limited cathode active material utilization, significant volume change have pledged the practical application of all‐solid‐state Li/S batteries (ASSLSBs). Herein, an unprecedented Li 2 S‐Li x In S 3 is designed whereby reacts with under high‐energy ball milling. situ electron diffraction ex XPS are implanted to probe reaction mechanism in ASSLSBs. The results indicate that serves as a mobility mediator for both charge‐carriers (Li + e − ) redox activation, ensuring efficient transportation at interface inhibiting ≈ 70% relative volumetric cathode, confirmed by TEM. Thus, delivers initial areal capacity 3.47 mAh cm −2 4.0 mg Li2S 78% utilization S. A solid‐state cell carries 82.35% retention over 200 cycles 0.192 mA remarkable rate capability up 0.64 RT. Besides, exhibits highest 4.08 ≈74.01% 50 versus 6.6 proposed strategy minimized realized outstanding electrochemical performance

Language: Английский

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