Ion Transport in (Localized) High Concentration Electrolytes for Li-Based Batteries

ACS Energy Letters, Journal Year: 2024, Volume and Issue: 9(2), P. 373 - 380

Published: Jan. 5, 2024

High concentration electrolytes (HCEs) and localized high (LHCEs) have emerged as promising candidates to enable higher energy density Li-ion batteries due their advantageous interfacial properties that result from unique solvent structures. Using electrophoretic NMR electrochemical techniques, we characterize report full transport properties, including the lithium transference numbers (t+) for ranging conventional ∼1 M HCE regimes well LHCE systems. We find compared electrolytes, t+ increases HCEs; however addition of diluents LHCEs significantly decreases t+. Viscosity effects alone cannot explain this behavior. Onsager coefficients calculated our experiments, demonstrate there is more positively correlated cation–cation motion in HCEs fast cation–anion ligand exchange consistent with a concerted ion-hopping mechanism. The results anticorrelated indicating disruption cation-hopping leading low LHCEs.

Language: Английский

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Stabilizing cathode-electrolyte interphase by localized high-concentration electrolytes for high-voltage sodium-ion batteries

Nano Energy, Journal Year: 2024, Volume and Issue: 123, P. 109389 - 109389

Published: Feb. 12, 2024

Language: Английский

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Electrolyte design combining fluoro- with cyano-substitution solvents for anode-free Li metal batteries

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(5)

Published: Jan. 22, 2024

Fluoro-substitution solvents have achieved great success in electrolyte engineering for high-energy lithium metal batteries, which, however, is beset by low solvating power, thermal and chemical instability, possible battery swelling. Instead, we herein introduce cyanogen as the electron-withdrawing group to enhance oxidative stability of ether solvents, which oxygen form chelating structure with Li + not notably undermining power. Cyano-group strongly bonds transition metals (TMs) NCM811 cathode attenuate catalytic reactivity TMs toward bulk electrolytes. Besides, a stable uniform cathode–electrolyte interphase (CEI) inhibits violent oxidation decomposition electrolytes guarantees structural integrity cathode. Also, N-containing LiF-rich solid–electrolyte (SEI) our facilitates fast migration dense deposition. Accordingly, enables cycle anode Coulombic efficiency 98.4% within 100 cycles. 81.8% capacity 4.3 V remains after 200 Anode-free pouch cells 125 mAh maintain 76% cycles, corresponding an energy density 397.5 Wh kg -1 .

Language: Английский

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Designing Nonflammable Liquid Electrolytes for Safe Li‐Ion Batteries

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

Published: May 1, 2024

Abstract Li‐ion batteries are essential technologies for electronic products in the daily life. However, serious fire safety concerns that closely associated with flammable liquid electrolyte remains a key challenge. Tremendous effort has been devoted to designing nonflammable electrolytes. It is critical gain comprehensive insights into nonflammability design and inspire more efficient approaches building safer batteries. This review presents current mechanistic understanding of issues discusses state‐of‐the‐art electrolytes based on molecule, solvation, battery compatibility level. Various test methods discussed reliable risk evaluation. Finally, challenges perspectives summarized.

Language: Английский

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A New Strategy for Sulfone‐Containing Electrolytes Design Enabling Long Cycling High‐Voltage Lithium‐Ion Batteries

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

Abstract High‐energy‐density lithium‐ion batteries (LIBs) face critical challenges due to the lack of electrolyte solvents that can achieve dual‐interfaces stability. Although ethyl mesylate (EM)‐based sulfone electrolytes are compatible with high‐voltage cathodes, their high viscosity and tendency EM's reactive sulfonate ester group decompose at graphite (Gr) anodes limit broad applications. Here, a novel approach is introduced uses single co‐solvent acetate (EA), methyl propionate (MP), or butyrate (MB) in an EM‐based modulate solvation interfacial chemistry bypassing high‐concentration lithium salt. These co‐solvents disrupt EM‐dominated structure, diminishing EM‐Li + interaction, allowing more oxalyldifluoroborate (LiODFB) integrate into primary Li shell facilitate formation stable electrode interphases. The designed ensure stability while solving incompatibility solvent EM anode. Consequently, 4.5 V Gr||LiNi 0.8 Co 0.1 Mn O 2 (NCM811) full cell demonstrates outstanding cycling stability, retaining 89.1% capacity after 500 cycles 1 C rate, average coulombic efficiency 99.92%. This innovative strategy offers practical for utilizing next‐generation batteries.

Language: Английский

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Reviewing recent progress of liquid electrolyte chemistry for mitigating thermal runaway in lithium‒ion batteries

Energy storage materials, Journal Year: 2023, Volume and Issue: 65, P. 103133 - 103133

Published: Dec. 12, 2023

Language: Английский

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Superior electrochemical performance of alkali metal anodes enabled by milder Lewis acidity

Energy & Environmental Science, Journal Year: 2024, Volume and Issue: 17(10), P. 3470 - 3481

Published: Jan. 1, 2024

Weak Lewis acidity of potassium-ions promotes enhanced anion incorporation into the solvation shell, facilitating formation a more stable and dissolution-resistant solid electrolyte interphase for K metal compared with that Li Na metals.

Language: Английский

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A weakly ion pairing electrolyte designed for high voltage magnesium batteries

Energy & Environmental Science, Journal Year: 2023, Volume and Issue: 17(1), P. 190 - 201

Published: Nov. 16, 2023

We report a solvent-designed Mg(TFSI) 2 electrolyte, which facilitates ion pair dissociation, nanoscale Mg nucleation/growth, and dendrite-free plating/stripping at mA h cm −2 , enabling full cell operation up to 3.5 V 2C rate for 400 cycles.

Language: Английский

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Ethylene Carbonate Regulated Solvation of Triethyl Phosphate to Enable High-Conductivity, Nonflammable, and Graphite Compatible Electrolyte

ACS Energy Letters, Journal Year: 2023, Volume and Issue: 9(1), P. 136 - 144

Published: Dec. 13, 2023

In the landscape of lithium-ion batteries (LIBs), carbonate-based electrolytes have driven remarkable progress, but persistent safety concerns stemming from their flammability necessitate innovative solutions. This study explores a cost-effective nonflammable cosolvent, triethyl phosphate (TEP), to counter risk. However, TEP's strong Li+-coordinating propensity adversely affects graphite (Gr) electrode intercalation. To surmount these challenges, we unveil competitive coordination behavior TEP and ethylene carbonate, strategically optimizing numbers. tailored approach culminates in dynamically stable structure which reduces adverse effects TEP. Leveraging insights, engineer TEP-modified carbonate electrolyte with standard Li salt concentration (1 M) boasting both nonflammability high ionic conductivity, enabling Gr anode achieve ∼100% capacity retention after 150 cycles. Additionally, this formulation significantly minimizes fire explosion risks 4 A h Gr||LiNi0.9Co0.05Mn0.05O2 pouch cells during mechanical stress, demonstrating profound implications for safer energy storage LIBs.

Language: Английский

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Towards stable electrode–electrolyte interphases: Regulating solvation structures in electrolytes for rechargeable batteries

Interdisciplinary materials, Journal Year: 2023, Volume and Issue: 2(6), P. 833 - 854

Published: Nov. 1, 2023

Abstract Rechargeable batteries are highly in demand to power various electronic devices and future smart electric grid energy storage. The electrode–electrolyte interphases play a crucial role influencing the electrochemical performance of batteries, with solvation chemistries electrolyte being particularly significant regulating these interfacial reactions. However, reaction mechanisms their specific functions not yet fully understood. In this review, we embark on an exploration fundamental principles governing present comprehensive overview how structures impact reactions at interface. We underscore significance interactions among cations, anions, solvents shaping structures. primary strategies for controlling also discussed, including optimization salt concentrations, solvent interactions, introduction functional cosolvents. Furthermore, elucidate oxidation/reduction components different new understanding additives modulating batteries. Additionally, emphasize importance incorporating characterization techniques theoretical simulations attain deeper intricate processes taking place within This review provides in‐depth solvations interphasial properties ideas designing advanced electrolytes rechargeable

Language: Английский

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