Achievement of High-Cyclability and high-Voltage Li-Metal Batteries by Heterogeneous SEI film with Internal Ionic Conductivity/External Electronic Insulativity Hybrid Structure

Ambient-air-stable Li3InCl6 halide solid electrolyte, with high ionic conductivity of 1.49 × 10−3 S cm−1 at 25 °C, delivers essential advantages over commercial sulfide-based solid electrolyte.

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High-Charge Density Polymerized Ionic Networks Boosting High Ionic Conductivity as Quasi-Solid Electrolytes for High-Voltage Batteries

ACS Applied Materials & Interfaces ◽

10.1021/acsami.8b19743 ◽

2019 ◽

Vol 11 (4) ◽

pp. 4001-4010 ◽

Cited By ~ 8

Author(s):

Xiaolu Tian ◽

Yikun Yi ◽

Pu Yang ◽

Pei Liu ◽

Long Qu ◽

...

Keyword(s):

Ionic Conductivity ◽

Charge Density ◽

High Voltage ◽

Solid Electrolytes ◽

High Ionic Conductivity ◽

High Charge ◽

High Charge Density

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Blend Hybrid Solid Electrolytes Based on LiTFSI Doped Silica-Polyethylene Oxide for Lithium-Ion Batteries

Membranes ◽

10.3390/membranes9090109 ◽

2019 ◽

Vol 9 (9) ◽

pp. 109 ◽

Cited By ~ 2

Author(s):

Jadra Mosa ◽

Jonh Fredy Vélez ◽

Mario Aparicio

Keyword(s):

Ionic Conductivity ◽

Solid Electrolytes ◽

Room Temperature ◽

Sol Gel ◽

Lithium Ion ◽

Hybrid Structure ◽

Hybrid Network ◽

Li Ion Batteries ◽

Li Ion ◽

Sol Gel Synthesis

Organic/inorganic hybrid membranes that are based on GTT (GPTMS-TMES-TPTE) system while using 3-Glycidoxypropyl-trimethoxysilane (GPTMS), Trimethyletoxisilane (TMES), and Trimethylolpropane triglycidyl ether (TPTE) as precursors have been obtained while using a combination of organic polymerization and sol-gel synthesis to be used as electrolytes in Li-ion batteries. Self-supported materials and thin-films solid hybrid electrolytes that were doped with Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) were prepared. The hybrid network is based on highly cross-linked structures with high ionic conductivity. The dependency of the crosslinked hybrid structure and polymerization grade on ionic conductivity is studied. Ionic conductivity depends on triepoxy precursor (TPTE) and the accessibility of Li ions in the organic network, reaching a maximum ionic conductivity of 1.3 × 10−4 and 1.4 × 10−3 S cm−1 at room temperature and 60 °C, respectively. A wide electrochemical stability window in the range of 1.5–5 V facilitates its use as solid electrolytes in next-generation of Li-ion batteries.

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High-Voltage Sulfolane Plasticized UV-Curable Gel Polymer Electrolyte

Polymers ◽

10.3390/polym11081306 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1306

Author(s):

Shiqi Wang ◽

Chun Wei ◽

Wenwen Ding ◽

Linmin Zou ◽

Yongyang Gong ◽

...

Keyword(s):

Activation Energy ◽

Ionic Conductivity ◽

Polymer Electrolyte ◽

High Voltage ◽

Gel Polymer Electrolyte ◽

Liquid Electrolyte ◽

Temperature Conductivity ◽

Electrochemical Window ◽

Specific Discharge ◽

Discharge Capacities

A high-voltage electrolyte can match high-voltage positive electrode material to fully exert its capacity. In this research, a sulfolane plasticized polymer electrolyte was prepared by in situ photocuring. First, the effect of the sulfolane content on the ionic conductivity of the gel polymer electrolyte was investigated. Results showed that the ionic conductivity variation trend was in good agreement with the exponential function model for curve fitting. Second, the activation energy was calculated from the results of the variable temperature conductivity tests. The activation energy was inversely proportional to the sulfolane content. For the sulfolane content of 80 wt. % in gel polymer electrolyte (GPE)-80 (19.5 kJ/mol), the activation energy was close to conventional liquid electrolyte (9.5 kJ/mol), and the conductivity and electrochemical window were 0.64 mS/cm and 5.86 V, respectively. The battery cycle performance test showed that the initial specific discharge capacities of GPE-80 and liquid electrolyte were 176.8 and 148.3 mAh/g, respectively. After 80 cycles, the discharge capacities of GPE-80 and liquid electrolyte were 115.8 and 41.1 mAh/g, and the capacity retention rates were 65.5% and 27.7%, respectively; indicating that GPE-80 has a better specific discharge capacity and cycling performance than the liquid electrolyte. SEM images indicated that GPE-80 can suppress the growth of lithium dendrites. The EDS test showed that GPE-80 can inhibit the dissolution of metal ions in the cathode material.

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An Electrolyte Additive for Use in High-Voltage Lithium-Ion Batteries

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.423-426.503 ◽

2013 ◽

Vol 423-426 ◽

pp. 503-506

Author(s):

Ai Fang Liu

Keyword(s):

Lithium Ion Batteries ◽

High Voltage ◽

Lithium Ion ◽

Electrolyte Composition ◽

Anode Surface ◽

Electrochemical Test ◽

Electrolyte Additive ◽

Sei Film ◽

Electrochemical Window ◽

Lowest Unoccupied Molecular Orbital

A new compound was successfully synthesized as an additive in electrolyte used for high-voltage lithium-ion batteries, owing to its unique structure with the sulfone group that can increase conductivity and broaden the electrochemical window of existing electrolyte. Its lowest unoccupied molecular orbital (LUMO) is-2.686 eV, respectively. The lower LUMO value results in formation of solid electrolyte interface (SEI) film on anode surface which is prior to other solvents and can impede the electrolyte composition. Through the electrochemical test, the electrolyte having this additive (0.2 wt%) showed wider voltage window, enduring the potential up to 5.5V higher than that of 4.8V performed by available commercial high-voltage electrolytes. The additive to electrolyte was effective not only for Li/Li3V2(PO4)3 cell but also for Li/LiMn2O4 cells with a cut-off range of 3.0-4.8 V.

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Theoretically predicting the feasibility of highly-fluorinated ethers as promising diluents for non-flammable concentrated electrolytes

Scientific Reports ◽

10.1038/s41598-020-79038-y ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Amine Bouibes ◽

Soumen Saha ◽

Masataka Nagaoka

Keyword(s):

Ionic Conductivity ◽

Ethyl Ether ◽

Diffusion Constant ◽

High Viscosity ◽

Self Diffusion ◽

Sei Film ◽

Concentrated Electrolytes ◽

Molecular Dynamics Calculations ◽

Fluorinated Ethers ◽

Fluorinated Ether

AbstractThe practical application of nonflammable highly salt-concentrated (HC) electrolyte is strongly desired for safe Li-ion batteries. Not only experimentalists but also theoreticians are extensively focusing on the dilution approach to address the limitations of HC electrolyte such as low ionic conductivity and high viscosity. This study suggests promising highly-fluorinated ethers to dilute the HC electrolyte based on non-flammable trimethyl phosphate (TMP) solvent. According to the quantum mechanical and molecular dynamics calculations, the fluorinated ether diluents showed a miscibility behavior in HC TMP-based electrolyte. While such miscibility behavior of the diluent with TMP solvent has been significantly enhanced by increasing its degree of fluorination, i.e., the “fluorous effect”, it is remarkable that the self-diffusion constant of Li+ and the ionic conductivity should be significantly improved by dilution with bis(1,1,2,2-tetrafluoro ethyl) ether (B2E) and bis(pentafluoro ethyl) ether (BPE) compared to other common hydrofluoroether diluents. In addition, the fluorinated-ether diluents have high ability to form a localized-concentrated electrolyte in HC TMP-based solution, leading to high expectation for the formation of a stable and a compact inorganic SEI film.

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Fluorinated Boron-Based Anions for Higher Voltage Li Metal Battery Electrolytes

Nanomaterials ◽

10.3390/nano11092391 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2391

Author(s):

Jonathan Clarke-Hannaford ◽

Michael Breedon ◽

Thomas Rüther ◽

Michelle J.S. Spencer

Keyword(s):

Ionic Conductivity ◽

High Voltage ◽

Density Functional ◽

Stability Limit ◽

Electrochemical Stability ◽

Ab Initio Molecular Dynamics ◽

Anode Surface ◽

Lithium Metal ◽

Metal Anode ◽

Sei Layer

Lithium metal batteries (LMBs) require an electrolyte with high ionic conductivity as well as high thermal and electrochemical stability that can maintain a stable solid electrolyte interphase (SEI) layer on the lithium metal anode surface. The borate anions tetrakis(trifluoromethyl)borate ([B(CF3)4]−), pentafluoroethyltrifluoroborate ([(C2F5)BF3]−), and pentafluoroethyldifluorocyanoborate ([(C2F5)BF2(CN)]−) have shown excellent physicochemical properties and electrochemical stability windows; however, the suitability of these anions as high-voltage LMB electrolytes components that can stabilise the Li anode is yet to be determined. In this work, density functional theory calculations show high reductive stability limits and low anion–cation interaction strengths for Li[B(CF3)4], Li[(C2F5)BF3], and Li[(C2F5)BF2(CN)] that surpass popular sulfonamide salts. Specifically, Li[B(CF3)4] has a calculated oxidative stability limit of 7.12 V vs. Li+/Li0 which is significantly higher than the other borate and sulfonamide salts (≤6.41 V vs. Li+/Li0). Using ab initio molecular dynamics simulations, this study is the first to show that these borate anions can form an advantageous LiF-rich SEI layer on the Li anode at room (298 K) and elevated (358 K) temperatures. The interaction of the borate anions, particularly [B(CF3)4]−, with the Li+ and Li anode, suggests they are suitable inclusions in high-voltage LMB electrolytes that can stabilise the Li anode surface and provide enhanced ionic conductivity.

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