CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Minhui Liao,Yang Zhou,Xunchang Jiang,Renjie Wan
High safety, high ion conductivity, and stable interface contacts are of significant importance for the application of solid-state electrolytes (SSEs) in solid-state lithium metal batteries (SSLMBs). In this study, SSEs with high ion conductivity and safety were constructed by in-situ polymerization of poly butyl acrylate (PBA) based electrolytes in the three-dimensional (3D) pores of a polyvinylidene fluoride (PVDF) nanofiber membrane, and embedded with ion conductor succinonitrile (SN), fluorinated ethylene carbonate (FEC), and imidazolium-based ionic liquid (IL). The test results and microscopic structural analysis indicate that SN is uniformly dispersed in PVDF, effectively reducing the crystallinity of solid polymer electrolytes (SPEs) and constructing a 3D interconnected lithium-ion conduction network. Consequently, an ion conductivity of 4.89 mS cm −1 was achieved at 25°C. Meanwhile, density functional theory (DFT) calculations demonstrated that imidazolium-based ionic liquid can adjust the dissolution characteristics of Li + through weak interactions with the polymer framework and strong coordination with TFSI - . X-ray photoelectron spectroscopy (XPS) characterization revealed that the imidazolium-based ionic liquid can form a stable solid electrolyte interface enriched with Li 3 N on the lithium-metal surface. The resulting SPEs demonstrated excellent ion conductivity, a high Li + transfer number (t Li + = 0.739), and a nanofiber-reinforced interpenetrating framework with a tensile strength of 17.15 MPa. Furthermore, the LiFePO 4 (LFP)||Li battery equipped with PBA-PVDF-SN (modified with IL) exhibited excellent electrochemical performance at room temperature with a capacity retention of 87.4 % after 800 cycles at 0.5C.
研究领域:
材料科学
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电化学
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电池技术
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聚合物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2023
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IF 9.9
Ran He,Kuirong Deng,Tianyu Guan,Fuhui Liang,Xiaoqiong Zheng,Maosheng Li,Daize Mo,Kai Yang,Haijiao Xie
In-situ preparation of polymer electrolytes (PEs) can enhance electrolyte/electrode interface contact and accommodate the current large-scale production line of lithium-ion batteries (LIBs). However, reactive initiators of in-situ PEs may lead to low capacity, increased impedance and poor cycling performance. Flammable and volatile monomers and plasticizers of in-situ PEs are potential safety risks for the batteries. Herein, we adopt lithium difluoro(oxalate)borate (LiDFOB)-initiated in-situ polymerization of solid-state non-volatile monomer 1,3,5-trioxane (TXE) to fabricate PEs (In-situ PTXE). Fluoroethylene carbonate (FEC) and methyl 2,2,2-trifluoroethyl carbonate (FEMC) with good fire retardance, high flash point, wide electrochemical window and high dielectric constant were introduced as plasticizers to improve ionic conductivity and flame retardant property of In-situ PTXE. Compared with previously reported in-situ PEs, In-situ PTXE exhibits distinct merits, including free of initiators, non-volatile precursors, high ionic conductivity of 3.76 × 10 −3 S cm −1 , high lithium-ion transference number of 0.76, wide electrochemical stability window (ESW) of 6.06 V, excellent electrolyte/electrode interface stability and effectively inhibition of Li dendrite growth on the lithium metal anode. The fabricated LiFePO 4 (LFP)/Li batteries with In-situ PTXE achieve significantly boosted cycle stability (capacity retention rate of 90.4% after 560 cycles) and outstanding rate capability (discharge capacity of 111.7 mAh g −1 at 3C rate).
研究领域:
材料科学
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电化学
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电池技术
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聚合物化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
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2025
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IF 5.6
Minghui Kong,Wenlong Wang,Jiaqiang Li,Qiang Yang,Runru Liu,Qi Liu,Daobin Mu,Li Li,Renjie Chen,Shuo Yang,Bin Wang,Feng Wu
This research explores the structural and interfacial regulation mechanisms of multi-element synergistic electrolytes for high voltage LiNi x Co y Mn 1-x-y O 2 (NCM) lithium ion batteries through a combined simulation-experiment approach. Theoretical calculations revealed that difluoroxalate borate ion (DFOB − ) exhibit a pronounced negative electrostatic potential distribution, with a binding energy to Li + (-110.26 kJ/mol) higher than conventional carbonate solvents (e.g., DMC, FEC), thus dominating the formation of anion-enriched solvation sheaths and significantly reducing Li + desolvation energy barriers (<30 kJ/mol). Raman spectroscopy and molecular dynamics simulations confirmed that LiDFOB introduction facilitates the transition of solvation structures from solvent-separated ion pairs (SSIPs) to contact ion pairs (CIPs) and aggregates (AGGs), with CIPs/AGGs proportion increasing from 29 % to 39 %, effectively suppressing LiPF 6 hydrolysis and mitigating electrode structural damage caused by solvent co-intercalation. Electrochemical tests demonstrated that the optimized 0.5 PB modified electrolyte(0.5 M lithium hexafluorophosphate+0.5 M lithium difluoro(oxalato)borate dissolved in a mixed solvent of dimethyl carbonate: fluoroethylene carbonate: propyl p-toluene sulfonate in a ratio of 3:1:1) enabled NCM811||Li half-cells to achieve 88 % capacity retention after 100 cycles at 4.5 V high voltage (versus 58 % for control group), along with stable lithium metal anode cycling for 500 h at 1 mA·cm −2 . Interface analysis revealed that DFOB⁻ and PPTs preferentially undergo redox reactions to form inorganic-rich cathode electrolyte interphase (CEI) films containing borides (LiₓBOyFz) and sulfonates (ROSO₂Li). On the anode side, synergistic effects of DFOB⁻, Propyl p-toluene sulfonate (PPTs) and FEC generate LiF/sulfur/boride-enriched composite solid electrolyte interface (SEI) layers, effectively suppressing transition metal dissolution and graphite structural degradation. This work provides a novel paradigm of "anion coordination-solvation structure-interface functionalization" for high-voltage lithium-ion batteries."
研究领域:
电化学
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能源材料
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锂离子电池
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电池界面工程
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计算材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）