A Solid-Liquid Hybrid Electrolyte With Weak-Solvated Solvent to Reduce Li⁺ Transfer Barrier at Electrode and Solid Electrolyte Interphase

Abstract

The interface problem caused by the contact between electrode and solid electrolyte (SE) is the main factor hindering the development of solid-state batteries. And adding liquid electrolyte (LE) at the interface to form a solid-liquid hybrid electrolyte is the common strategy. The ion transport kinetics at the SE/LE interface include an active role for the (de)solvation of ions, and the energy barrier for Li⁺ transport between the liquid and solid phases is closely related to the solvation capacity of the solvent. Herein, the influence of the solvation structure of the electrolyte itself on the interface is investigated. Compared to dimethyl carbonate (DMC), the lower Li⁺ binding energy of tetrahydrofuran (THF) is more easily desolvated at the solid-liquid interface, allowing the formation of abundant aggregates and the generation of inorganic-rich interfacial phases, leading to interfacial compatibility. Using the combination of polyvinylidene fluoride (PVDF)-based SPE and THF-based LE, the cycle performance and rate performance of LiFePO₄(LFP) |SPE|Li batteries are improved. The Li/Li symmetric cell can achieve stable cycling over 1000 h at a current density of 0.05 mA cm⁻², and LFP/Li half-cell retains 93% of its initial capacity after 100 cycles at 0.5 C. This study can provide inspiration for the design of solid-LE interface.

Keywords

Li⁺ transfer barrier / lithium-ion battery / solid-liquid electrolyte interphase / solvation structures / weak-solvated solvent

References

[1] X. Cai, S. Li, J. Zhou, J. Zhang, N. Zhang, and X. Cui, “Mitigating Chain Degradation of Lithium-Rich Manganese-Based Cathode Material by Surface Engineering,” Energy Storage Materials 71 (2024): 103624.

[2] X. Cui, S. Wang, X. Ye, et al., “Insights Into the Improved Cycle and Rate Performance by Ex-Situ F and In-Situ Mg Dual Doping of Layered Oxide Cathodes for Sodium-Ion Batteries,” Energy Storage Materials 45 (2022): 1153-1164.

[3] Z. Bi, Q. Sun, M. Jia, M. Zuo, N. Zhao, and X. Guo, “Molten Salt Driven Conversion Reaction Enabling Lithiophilic and Air-Stable Garnet Surface for Solid-State Lithium Batteries,” Advanced Functional Materials 32 (2022): 2208751.

[4] M. Jia, Z. Bi, and X. Guo, “Ionic-Electronic Dual-Conductive Polymer Modified LiCoO₂ Cathodes for Solid Lithium Batteries,” Chemical Communications 58 (2022): 8638-8641.

[5] R. Liu, R. Li, L. Yang, et al., “FeOOH Quantum Dot-Coupled Z-Scheme BiVO₄/g-C₃N₄ Heterojunction for Enhancing Photo-Fenton Reactions,” ACS Applied Nano Materials 6 (2023): 17009-17020.

[6] J. Ma, S. Zhang, Y. Zheng, et al., “Interelectrode Talk in Solid-State Lithium-Metal Batteries,” Advanced Materials 35 (2023): 2301892.

[7] J. X. Li, L. Zhong, H. Wu, et al., “A Novel Na-β″-Al₂O₃ Nanosheet Enhanced Environmentally Friendly Solid Electrolyte for a Highly Stable Na-Metal Battery,” ACS Sustainable Chemistry & Engineering 12 (2024): 18058-18067.

[8] X. F. Yang, M. Jiang, X. J. Gao, et al., “Determining the Limiting Factor of the Electrochemical Stability Window for PEO-Based Solid Polymer Electrolytes: Main Chain or Terminal -OH Group?,” Energy & Environmental Science 13 (2020): 1318-1325.

[9] S. Mu, W. Huang, W. Sun, et al., “Heterogeneous Electrolyte Membranes Enabling Double-Side Stable Interfaces for Solid Lithium Batteries,” Journal of Energy Chemistry 60 (2021): 162-168.

[10] M. Jia, Z. Bi, C. Shi, N. Zhao, and X. Guo, “Air-Stable Dopamine-Treated Garnet Ceramic Particles for High-Performance Composite Electrolytes,” Journal of Power Sources 486 (2021): 229363.

[11] R. T. Zhan, Z. Z. Yang, I. Bloom, and L. Pan, “Significance of a Solid Electrolyte Interphase on Separation of Anode and Cathode Materials From Spent Li-Ion Batteries by Froth Flotation,” ACS Sustainable Chemistry & Engineering 9 (2021): 531-540.

[12] P. Li, Y. Huang, Y. Yu, X. Ma, Z. Wang, and G. Shao, “Recent Advances and Future Prospects for PVDF-Based Solid Polymer Electrolytes,” Journal of Power Sources 628 (2025): 235855.

[13] H. Diao, M. Jia, N. Zhao, and X. Guo, “LiNi_0.6Co_0.2Mn_0.2O₂ Cathodes Coated With Dual-Conductive Polymers for High-Rate and Long-Life Solid-State Lithium Batteries,” ACS Applied Materials & Interfaces 14 (2022): 24929-24937.

[14] P. Yao, B. Zhu, H. Zhai, et al., “PVDF/Palygorskite Nanowire Composite Electrolyte for 4 V Rechargeable Lithium Batteries With High Energy Density,” Nano Letters 18 (2018): 6113-6120.

[15] P. Zhai, Z. Yang, Y. Wei, X. Guo, and Y. Gong, “Two-Dimensional Fluorinated Graphene Reinforced Solid Polymer Electrolytes for High-Performance Solid-State Lithium Batteries,” Advanced Energy Materials 12 (2022): 2200967.

[16] J. Ding, X. Li, L. Gong, and P. Tan, “Investigating the Failure Mechanism of Solid Electrolyte Interphase in Silicon Particles From an Electrochemical-Mechanical Coupling Perspective,” Advanced Powder Materials 3 (2024): 100200.

[17] L. Ma, Y. Dong, N. Li, et al., “Current Challenges and Progress in Anode/Electrolyte Interfaces of All-Solid-State Lithium Batteries,” eTransportation 20 (2024): 100312.

[18] J. Kondo, K. Otani, S. Miyamoto, et al., “Stabilizing the Solid/Liquid Interface in Quasi-Solid Electrolytes via Anion-Derived Interphase Formation in Concentrated Solutions,” ACS Applied Energy Materials 8 (2025): 2630-2637.

[19] J. Tang, L. Wang, L. You, et al., “Effect of Organic Electrolyte on the Performance of Solid Electrolyte for Solid-Liquid Hybrid Lithium Batteries,” ACS Applied Materials & Interfaces 13 (2021): 2685-2693.

[20] C. Wang, Q. Sun, Y. Liu, et al., “Boosting the Performance of Lithium Batteries With Solid-Liquid Hybrid Electrolytes: Interfacial Properties and Effects of Liquid Electrolytes,” Nano Energy 48 (2018): 35-43.

[21] X. Li, L. N. Cong, S. C. Ma, et al., “Low Resistance and High Stable Solid-Liquid Electrolyte Interphases Enable Highvoltage Solid-State Lithium Metal Batteries,” Advanced Functional Materials 31 (2021): 2010611.

[22] M. R. Busche, T. Drossel, T. Leichtweiss, et al., “Dynamic Formation of a Solid-Liquid Electrolyte Interphase and Its Consequences for Hybrid-Battery Concepts,” Nature Chemistry 8 (2016): 426-434.

[23] Y. Quan, X. L. Cui, L. Hu, et al., “Enhancing Li ⁺ Transportation at Graphite-Low Concentration Electrolyte Interface via Interphase Modulation of LiNO₃ and Vinylene Carbonate,” Carbon Neutralization 4 (2024): e184.

[24] J. W. Zhang, J. L. Sun, D. N. Zhao, et al., “Tuning Solvation Structure to Enhance Low Temperature Kinetics of Lithium-Ion Batteries,” Energy Storage Materials 72 (2024): 103698.

[25] Y. Liao, W. Lin, Y. Zhang, et al., “A Weakly Solvating Ether Electrolyte Enables Fast-Charging and Wide-Temperature Lithium-Ion Pouch Cells,” ACS Nano 18 (2024): 20762-20771.

[26] X. Cui, J. Sun, D. Zhao, et al., “Mechanism of High-Concentration Electrolyte Inhibiting the Destructive Effect of Mn(II) on the Performance of Lithium-Ion Batteries,” Journal of Energy Chemistry 78 (2023): 381-392.

[27] H. Li, C. Yan, and S. Wang, “Solvation Chemistry in Liquid Electrolytes for Rechargeable Lithium Batteries at Low Temperatures,” EcoEnergy 3 (2025): 387-421.

[28] P. Du, J. Wan, B. Qiu, et al., “Engineering the Solvent-Anion Interactions of LiTFSI-Based Dual-Salt Electrolytes to Sustain High-Performance NCM622 Cathodes,” Energy Storage Materials 73, no. 204 (2024): 103816.

[29] D. Zhao, Y. Zhao, P. Wang, et al., “Enhancing Electric Field Intensity of Interfacial Electric Double Layer to Improve Properties of Solid Electrolyte Interface for Sodium-Ion Batteries,” Applied Surface Science 679 (2025): 161202.

[30] C. Li, Y. Zhu, Y. Quan, et al., “Mitigating Volume Expansion of Silicon-Based Anode Through Interfacial Engineering Based on Intermittent Discharge Strategy,” Journal of Energy Chemistry 98 (2024): 680-691.

[31] L. Niu, M. Wu, Y. Zhang, et al., “Surface Phosphorylated Li₅FeO₄ Prelithiation Additive Synergistically Improves the Air-Stability and Lithium-Ion Conductivity,” Chemical Engineering Journal 498 (2024): 155242.

[32] S. Y. Li, J. N. Li, P. Wang, et al., “Interface Engineering Regulation by Improving Self-Decomposition of Lithium Salt-Type Additive Using Ultrasound,” Advanced Functional Materials 34 (2023): 2307180.

[33] S. Li, Y. Zhang, S. Wu, et al., “Synchronized Achieving Amount Reduction and Efficiency Increase of Lithium Salt-Type Additive by Alternating Current Pulse Discharge Technology,” Chemical Engineering Journal 485 (2024): 150095.

[34] N. Zhang, B. Wang, M. Chen, et al., “Revisiting the Impact of Co at High Voltage for Advanced Nickel-Rich Cathode Materials,” Energy Storage Materials 67 (2024): 103311.

RIGHTS & PERMISSIONS

2025 The Author(s). Battery Energy published by Xijing University and John Wiley & Sons Australia, Ltd.