Li Anode Surface Research Articles

Functional organic 7,7,8,8‐tetracyanoquinodimethane artificial layers for the dendrite suppressed lithium metal anodes

AbstractThe large‐scale industrialization of lithium metal (Li), as a potential anode for a high energy density energy storage system, has been hindered by dendrite growth. The construction of an artificial solid electrolyte interphase layer featuring high ionic and low electronic conductivity has been verified to be a high‐performance strategy to confine the dendrite growth and promote the Li anode stability. Therefore, a functional organic protective layer is homogeneously deposited on the Li anode surface via an in situ chemical reaction between tetracyanoquinodimethane (TCNQ) and Li. The as‐synthesized Lin‐TCNQ organic film could efficiently trap non‐uniform Li deposition and restrain dendrite propagation. Particularly, an asymmetric M‐TCNQ‐Li|Cu cell with the Lin‐TCNQ layer breezed through a high Coulombic efficiency of 91.15% after 100 cycles at 1.0 mA cm−2. The M‐TCNQ‐Li|NCM622 cell delivered a high capacity of 143.40 mAh g−1 at 0.2 C and maintained a good cyclic stability of 110.44 mAh g−1 after 160 cycles. The analysis results of spectroscopic tests further demonstrate that the Lin‐TCNQ with the enhanced absorption energy is conducive to lithiophilicity and decreases the overpotential of Li deposition.

Interface Stability and Reaction Mechanisms of Li3YCl5Br with High-Voltage Cathodes and Li Metal Anode: Insights from Ab Initio Simulations.

Recent advancements in battery technology emphasize the critical role of solid electrolytes in enhancing the performance and safety of next-generation batteries. In this study, we investigate the interface stability and reaction mechanisms of Li3YCl5Br, a promising halide-based solid electrolyte, in contact with high-voltage Ni-Mn-Co (NMC) cathodes and a Li metal anode using ab initio molecular dynamics simulations. Our findings reveal that Li3YCl5Br reacts with charged NMC cathodes. This reaction involves changes in the oxidation states of Br- anions in Li3YCl5Br and d-element cations in NMC, as well as the diffusion of Li ions from the solid electrolyte to the cathode to maintain charge balance. The reaction is confined to the interface, suggesting bulk stability. Conversely, the Li/Li3YCl5Br interface exhibits significant instability, with a chemical reaction that results in substantial structural changes and the formation of LiCl and LiBr at the solid electrolyte surface and metallic Y at the Li anode surface. These insights provide valuable information for optimizing interfacial design, aiming at improving the performance and reliability of all-solid-state batteries using halide solid electrolytes.

Lithium surface engineering with in-situ generated Fe/Li2O/LiCl mixed electron/ion conductive layer for stable lithium metal batteries

The lithium metal batteries (LMBs) using metallic Li as anode with high-energy density have been prevailed in the field of energy storage, while the aggregation of Li dendrites and brittle solid state electrolyte interface (SEI) impede the development of Li anode. In this work, to regulate the interface of Li anode, a Fe/Li2O/LiCl mixed electron/ion conducting layer is in-situ generated on the surface of Li anode, which is derived from the electrochemical reaction between Li anode and Fe2O3/FeOCl coatings on commercial separator. The synergistic effect between electron conductive Fe and ion conductive Li2O/LiCl is beneficial to build up dense and uniform SEI and promote uniform Li+ flux, resulting in smooth Li deposition, which will further stabilize the Li metal surface and prolong the battery life of LMBs. Specifically, the symmetric Li||Li cells with Fe2O3/FeOCl can operate steadily for 600 h at 1 mAh cm−2 without obvious voltage polarization, and the corresponding full battery matched with S-PAN delivers capacity retention of 64.43 % at 500 mA g−1 after 350 cycles.

Atomic-Scale Cryo-TEM Studies of the Electrochemistry of Redox Mediator in Li-O2 Batteries.

Rechargeable aprotic lithium (Li)-oxygen battery (LOB) is a potential next-generation energy storage technology because of its high theoretical specific energy. However, the role of redox mediator on the oxide electrochemistry remains unclear. This is partly due to the intrinsic complexity of the battery chemistry and the lack of in-depth studies of oxygen electrodes at the atomic level by reliable techniques. Herein, cryo-transmission electron microscopy (cryo-TEM) is used to study how the redox mediator LiI affects the oxygen electrochemistry in LOBs. It is revealed that with or without LiI in the electrolyte, the discharge products are plate-like LiOH or toroidal Li2O2, respectively. The I2 assists the decomposition of LiOH via the formation of LiIO3 in the charge process. In addition, a LiI protective layer is formed on the Li anode surface by the shuttle of I3 -, which inhibits the parasitic Li/electrolyte reaction and improves the cycle performance of the LOBs. The LOBs returned to 2e- oxygen reduction reaction (ORR) to produce Li2O2 after the LiI in the electrolyte is consumed. This work provides new insight on the role of redox mediator on the complex electrochemistry in LOBs which may aid the design LOBs for practical applications.

Glycerol-tailored asymmetric polyethersulfone membranes with uniform ion transport for stable lithium metal batteries

Advancing the performance and stability of lithium metal batteries is crucial for future energy storage devices. One of the major challenges for practical applications of Li metal batteries is to mitigate the formation of Li dendrites during cycling. In this work, we prepared a series of asymmetrically structured polyethersulfone (PES) membranes, consisting of a nanoporous skin layer and a bulk with macrovoids, by incorporating different amounts of glycerol during membrane preparation. Under optimal conditions, the asymmetric PES membrane made with 1.2 wt% of glycerol (PES-G1.2) possesses a thin skin layer with a uniform nanopore distribution, which is ideal for regulating the ion flux near the Li anode surface, thus suppressing Li dendrite formation. Our results demonstrate that the PES-G1.2 possesses exceptional ionic conductivity of 1.76 mS cm−1, Li+ transference number of 0.52, and high compatibility with Li electrode. Additionally, the Li/PES-G1.2/LiFePO4 cells also present a remarkable rate capability with specific capacity of 150 mAh g−1 at 0.2 C and 81 mAh g−1 at 10 C, respectively, and 90 % of capacity can be retained after 100 charge-discharge cycles under 0.2 C. These findings shed light on the unique properties of asymmetric porous membrane as well as its promising potential for applications in lithium metal batteries.

Interface design for all-solid-state lithium batteries.

The operation of high-energy all-solid-state lithium-metal batteries at low stack pressure is challenging owing to the Li dendrite growth at the Li anodes and the high interfacial resistance at the cathodes1-4. Here we design a Mg16Bi84 interlayer at the Li/Li6PS5Cl interface to suppress the Li dendrite growth, and a F-rich interlayer on LiNi0.8Mn0.1Co0.1O2 (NMC811) cathodes to reduce the interfacial resistance. During Li plating-stripping cycles, Mg migrates from the Mg16Bi84 interlayer to the Li anode converting Mg16Bi84 into a multifunctional LiMgSx-Li3Bi-LiMg structure with the layers functioning as a solid electrolyte interphase, a porous Li3Bi sublayer and a solid binder (welding porous Li3Bi onto the Li anode), respectively. The Li3Bi sublayer with its high ionic/electronic conductivity ratio allows Li to deposit only on the Li anode surface and grow into the porous Li3Bi sublayer, which ameliorates pressure (stress) changes. The NMC811 with the F-rich interlayer converts into F-doped NMC811 cathodes owing to the electrochemical migration of the F anion into the NMC811 at a high potential of 4.3 V stabilizing the cathodes. The anode and cathode interlayer designs enable the NMC811/Li6PS5Cl/Li cell to achieve a capacity of 7.2 mAh cm-2 at 2.55 mA cm-2, and the LiNiO2/Li6PS5Cl/Li cell to achieve a capacity of 11.1 mAh cm-2 with a cell-level energy density of 310 Wh kg-1 at a low stack pressure of 2.5 MPa. The Mg16Bi84 anode interlayer and F-rich cathode interlayer provide a general solution for all-solid-state lithium-metal batteries to achieve high energy and fast charging capability at low stack pressure.

The multifunctional 2-Trifluoroacetyl furan electrolyte additive for suppressing lithium dendrite growth

Constructing electrode-electrolyte interphase and enhancing wettability between separator and electrolyte are vital to electrochemical performances of Lithium-metal batteries, especially for suppressing the growth of Li dendrites. In this work, 2-Trifluoroacetyl furan is developed as the multifunctional additive to inhibit Li dendrite growth, and then enhance the cycling time and rate performance of Li||LiNi0.6Co0.2Mn0.2O2 (NCM622) cells. TFFE additive can enhance the Li ion flowing efficiency by improving wettability between separator and electrolyte and providing more channel of Li ions. Furthermore, TFFE can not only form solid electrolyte interphase (SEI) on the surface of Li anode, but also forms cathode electrolyte interphase (CEI) on the surface of NCM622 electrode. Finally, TFFE could stabilize the LiPF6-based electrolyte by removing hydrogen fluoride (HF) and H2O, protecting the generated SEI/CEI layer. As a result, introducing 1.0 wt% TFFE additive, the Li||Li symmetric cells could achieve stable cycling for 780 h at 0.5 mA cm−2, which is higher than that in baseline electrolyte (350 h). And, Li||NCM622 cells in the 1.0 wt% TFFE-contained electrolyte displays remarkably enhanced capacity of 90 % almost after 200 cycles.

An upgraded polymeric composite with interparticle chemical bonding microstructure toward lithium-ion battery separators with enhanced safety and electrochemical performances

A composite separator of SiC/PVDF-HFP was synthesized for lithium-ion batteries with high thermal and mechanical stabilities. Benefiting from the nanoscale, high hardness, and melting point of SiC, SiC/PVDF-HFP with highly uniform microstructure was obtained. This polarization caused by barrier penetration was significantly restrained. Due to the Si-F bond between SiC and PVDF-HFP, the structural stability has been obviously enhanced, which could suppress the growth of lithium (Li) dendrite. Furthermore, some 3D reticulated Si nanowires are found on the surface of Li anode, which also greatly inhibit Li dendrites and result in irregular flakes of Li metal. Especially, the shrinkage of 6% SiC/PVDF-HFP at 150 °C is only 5%, which is notably lower than those of PVDF-HFP and Celgard2500. The commercial LiFePO4 cell assembled with 6% SiC/PVDF-HFP possesses a specific capacity of 157.8 mA h g−1 and coulomb efficiency of 98% at 80 °C. In addition, the tensile strength and modulus of 6% SiC/PVDF-HFP could reach 14.6 and 562 MPa, respectively. And a small deformation (1000 nm) and strong deformation recovery are obtained under a high additional load (2.3 mN). Compared with PVDF-HFP and Celgard2500, the symmetric Li cell assembled with 6% SiC/PVDF-HFP has not polarized after 900 cycles due to its excellent mechanical stabilities. This strategy provides a feasible solution for the composite separator of high-safety batteries with a high temperature and impact resistance.

Facile construction of a water-defendable Li anode protection enables rechargeable Li-O2 battery operating in humid atmosphere

The rechargeable Li-O2 battery endowed with high theoretical specific energy density has sparked intense research interest as a promising energy storage system. However, the intrinsic high activity of Li anode, especially to moisture, usually leads to inferior electrochemical performance of Li-O2 battery in humid environments, hindering its widespread application. To settle the trouble of poor moisture tolerance, fabricating a water-proof layer on the Li-metal anode could be an effective tactic. Herein, a facile strategy for constructing an ibuprofen-based protective layer on the Li anode has been proposed to realize highly rechargeable Li-O2 battery in humid atmosphere. Due to the in-situ reaction between ibuprofen reagent and metallic Li, the protective layer with a thickness of ∼30 µm has been uniformly deposited on the surface of Li anode. Particularly, the protective layer, consisting of a large amount of hydrophobic alkyl group and benzene ring, can significantly resist water ingress and enhance the electrochemical stability of Li anode. As a result, the Li-O2 battery based on the protected Li anode achieves a long cycle life of 210 h (21 cycles at 1000 mAh/g, 200 mA/g) in highly moist atmosphere with relative humidity (RH) of 68%. This convenient and efficient strategy offers novel design concept of water-resistant metal anode, and paves the way to the promising future prospect for the high-energy Li-O2 battery implementing in the ambient atmosphere.

Uniform lithium deposition induced by copper phthalocyanine additive for durable lithium anode in lithium-sulfur batteries

Copper phthalocyanine (CuPc) is adopted as an electrolyte additive to stabilize lithium anode for lithium-sulfur (Li-S) batteries. CuPc with a planar molecular structure and lithiophilic N-containing group, is likely to be adsorbed on the surface of Li anode to form a coating layer, which can restrict the direct contact between Li anode and solvents, and guide the uniform deposition of Li+ ions. The Li||Li symmetric cells demonstrate a stable cycle performance, and Li||Cu cells show high Coulombic efficiencies. In Li-S batteries, the formed stable solid-electrolyte interface (SEI) film containing copper sulfides can protect Li anode from the polysulfide corrosion and side reactions with the electrolyte, leading to the compact and smooth surface morphology of Li anode. Therefore, the Li-S batteries with CuPc additive deliver much higher capacity, better cycle performance and rate capability as compared to the one without CuPc additive.

Ameliorating Phosphonic-Based Nonflammable Electrolytes Towards Safe and Stable Lithium Metal Batteries.

High-energy-density lithium metal batteries with high safety and stability are urgently needed. Designing the novel nonflammable electrolytes possessing superior interface compatibility and stability is critical to achieve the stable cycling of battery. Herein, the functional additive dimethyl allyl-phosphate and fluoroethylene carbonate were introduced to triethyl phosphate electrolytes to stabilize the deposition of metallic lithium and accommodate the electrode-electrolyte interface. In comparison with traditional carbonate electrolyte, the designed electrolyte shows high thermostability and inflaming retarding characteristics. Meanwhile, the Li||Li symmetrical batteries with designed phosphonic-based electrolytes exhibit a superior cycling stability of 700 h at the condition of 0.2 mA cm-2, 0.2 mAh cm-2. Additionally, the smooth- and dense-deposited morphology was observed on an cycled Li anode surface, demonstrating that the designed electrolytes show better interface compatibility with metallic lithium anodes. The Li||LiNi0.8Co0.1Mn0.1O2 and Li||LiNi0.6Co0.2Mn0.2O2 batteries paired with phosphonic-based electrolytes show better cycling stability after 200 and 450 cycles at the rate of 0.2 C, respectively. Our work provides a new way to ameliorate nonflammable electrolytes in advanced energy storage systems.

Solvent‐Free Electrolyte for High‐Temperature Rechargeable Lithium Metal Batteries

AbstractThe formation of lithiophobic inorganic solid electrolyte interphase (SEI) on Li anode and cathode electrolyte interphase (CEI) on the cathode is beneficial for high‐voltage Li metal batteries. However, in most liquid electrolytes, the decomposition of organic solvents inevitably forms organic components in the SEI and CEI. In addition, organic solvents often pose substantial safety risks due to their high volatility and flammability. Herein, an organic‐solvent‐free eutectic electrolyte based on low‐melting alkali perfluorinated‐sulfonimide salts is reported. The exclusive anion reduction on Li anode surface results in an inorganic, LiF‐rich SEI with high capability to suppress Li dendrite, as evidenced by the high Li plating/stripping CE of 99.4% at 0.5 mA cm−2 and 1.0 mAh cm−2, and 200‐cycle lifespan of full LiNi0.8Co0.15Al0.05O2 (2.0 mAh cm−2) || Li (20 µm) cells at 80 °C. The proposed eutectic electrolyte is promising for ultrasafe and high‐energy Li metal batteries.

A Novel Potassium Salt Regulated Solvation Chemistry Enabling Excellent Li-Anode Protection in Carbonate Electrolytes.

In lithium-metal batteries (LMBs), the compatibility of Li anode and conventional lithium hexafluorophosphate-(LiPF6 ) carbonate electrolyte is poor owing to the severe parasitic reactions. Herein, to resolve this issue, a delicately designed additive of potassium perfluoropinacolatoborate (KFPB) is unprecedentedly synthesized. On the one hand, KFPB additive can regulate the solvation structure of the carbonate electrolyte, promoting the formation of Li+ FPB- and K+ PF6 - ion pairs with lower lowest unoccupied molecular orbital (LUMO) energy levels. On the other hand, FPB- anion possesses strong adsorption ability on Li anode. Thus, anions can preferentially adsorb and decompose on the Li-anode surface to form a conductive and robust solid-electrolyte interphase (SEI) layer. Only with a trace amount of KFPB additive (0.03m) in the carbonate electrolyte, Li dendrites' growth can be totally suppressed, and Li||Cu and Li||Li half cells exhibit excellent Li-plating/stripping stability upon cycling. Encouragingly, KFPB-assisted carbonate electrolyte enables high areal capacity LiCoO2 ||Li, LiNi0.8 Co0.1 Mn0.1 O2 (NCM811)||Li, and LiNi0.8 Co0.05 Al0.15 O2 (NCA)||Li LMBs with superior cycling stability, showing its excellent universality. This work reveals the importance of designing novel additives to regulate the solvation structure of carbonate electrolytes in improving its interface compatibility with the Li anode.

Stable Non‐flammable Phosphate Electrolyte for Lithium Metal Batteries via Solvation Regulation by the Additive

AbstractThe application of lithium metal batteries (LMBs) is impeded by safety concerns. Employing non‐flammable electrolytes can improve battery reliability while the cost and performance deterioration limit their popularization. Herein, a high‐performance non‐flammable electrolyte is designed, 1.5 m LiTFSI in propylene carbonate (PC)/triethyl phosphate (TEP) (4:1 by vol.) with 4‐nitrophenyl trifluoroacetate (TFANP) as the additive, which can facilitate the construction of LiF‐rich solid electrolyte interphase (SEI) on Li anode surface and cathode electrolyte interphase (CEI) on cathode surface through its prioritized decomposition. In TFANP‐containing electrolyte, the decreased TEP coordination number in the solvation sheath relieves the adverse effect of active TEP on both the SEI and CEI for suppressing the growth of Li dendrites and reducing the continuous electrolyte consumption. Thus, the Li||LiNi0.6Co0.2Mn0.2O2 battery with such an electrolyte can deliver 132 mAh g−1 after 150 cycles with high coulombic efficiency (99.5%) and superior rate performance (110 mAh g−1 at 5 C, 1 C = 200 mA g−1). This work provides a new additive insight on non‐flammable electrolyte for reliable LMBs.

Enhanced cycle stability of aprotic Li-O2 batteries based on a self-defensed redox mediator

LiBr as a promising redox mediator (RM) has been applied in Li-O2 batteries to improve oxygen evolution reaction kinetics and reduce overpotentials. However, the redox shuttle of Br3− can induce the unexpected reactions and thus cause the degradation of LiBr and the corrosion of Li anode, resulting in the poor cyclability and the low round-trip efficiency. Herein, MgBr2 is firstly employed with dual functions for Li-O2 batteries, which can serve as a RM and a SEI film-forming agent. The Br– is beneficial to facilitating the decomposition of Li2O2 and thus decreasing the overpotential. Additionally, a uniform SEI film containing Mg and MgO generates on Li anode surface by the in-situ spontaneous reactions of Mg2+ and Li anode in an O2 environment, which can suppress the redox shuttle of Br3− and improve the interface stability of Li anode and electrolyte. Benefiting from these advantages, the cycle life of Li-O2 battery with MgBr2 electrolyte is significantly extended.

A novel flame-retardant nitrile-based gel polymer electrolyte for quasi-solid-state lithium metal batteries

In this work, a novel type of highly Li+-ions conductive, nonflammable adiponitrile (ADN)-based gel polymer electrolyte (denoted as AT11-GF) was prepared as a promising solid-state electrolyte for lithium (Li)-metal batteries by in-situ polymerization method. In order to overcome the parasitic reactions of ADN and triethyl phosphate (TEP) on Li-anode surface, fluoroethylene carbonate (FEC) was utilized as film-forming agent to generate LiF-enrich interface in this system of ADN-based electrolyte. The as-prepared electrolyte exhibited high ionic conductivity of 1.724 × 10−3 S/cm at ambient temperature, wide electrochemical window (∼5.75 V vs. Li+/Li), favorable Li+-ion transfer number (tLi+=0.70), and superior interfacial compatibility with Li anode (ultra-stable at a current density of 0.2 mA/cm2 for 1000 h). The LiFePO4|AT11-GF|Li battery presented an excellent rate capacity of 116.9 mAh/g at 2.0 C, and long-term cycling performance with a specific capacity of 134.6 mAh/g and a capacity retention of 94.5% after 1000 cycles at a current density of 1.0 C. Therefore, this as-prepared ADN-based electrolyte exhibited great promise for the application in solid-state Li-metal batteries.

Preferential decomposition of the major anion in a dual-salt electrolyte facilitates the formation of organic-inorganic composite solid electrolyte interphase.

The performance of a lithium metal battery (LMB) with liquid electrolytes depends on the realization of a stable solid electrolyte interphase (SEI) on the Li anode surface. According to a recent experiment, a high-concentrated (HC) dual-salt electrolyte is effective in modulating the SEI formation and improving the battery performance. However, the underlying reaction mechanism between this HC dual-salt electrolyte and the lithium metal anode surface remains unknown. To understand the SEI formation mechanism, we first performed 95ps ab initio Molecular Dynamics (AIMD) simulation and then extend this AIMD simulation to another 1ns by using Hybrid ab Initio and Reactive Molecular Dynamics (HAIR) to investigate the deep reactions of such dual-salt electrolytes consists of lithium difluorophosphate and lithium bis(trifluoromethanesulfonyl)imide in dimethoxyethane (DME) solvent at lithium metal anode surface. We observed the detailed reductive decomposition processes of DFP- and TFSI-, which include the formation pathway of CF3 fragments, LiF, and LixPOFy, the three main SEI components observed experimentally. Furthermore, after extending the simulation to 1.1ns via the HAIR scheme, the decomposition reactions of DME solvent molecules were also observed, producing LiOCH3, C2H4, and precursors of organic oligomers. These microscopic insights provide important guidance in designing the advanced dual-salt electrolytes for developing high-performance LMB.

Dynamic Ion Sieve as the Buffer Layer for Regulating Li+ Flow in Lithium Metal Batteries

AbstractHow to realize uniform Li+ flow is the key to achieve even Li deposition for lithium metal batteries (LMBs). In this study, a concept of dynamic ion sieve is proposed to design the buffer layer nearby Li anode surface to regulate Li+ spatial arrangement by introducing tributylmethylphosphonium bis(trifluoromethanesulfonyl)imide (TMPB) into the carbonate electrolyte. The buffer layer induced by TMP+ can adjust the velocity of arriving solvated Li+ that gives solvated Li+ sufficient time to redistribute and accumulate on Li anode surface, resulting in a uniform and higher concentrated Li+ flow. Besides, TFSI− can participate in the generation of inorganic component‐rich solid electrolyte interphase (SEI) with Li3N, which can facilitate the Li+ conductivity of SEI. Consequently, the stable and uniform Li deposition can be obtained, achieving the excellent cycling performance up to 1000 h at 0.5 mA cm−2 in the Li||Li symmetric cell. Besides, the Li||NCM622 full cell also possesses excellent cycling stability with a high‐capacity retention rate of 66.7% after 300 cycles.

Amide‐Functional, Li3N/LiF‐Rich Heterostructured Electrode Electrolyte Interphases for 4.6 V Li||LiCoO2 Batteries

AbstractEnhancing the charge cut‐off voltage of LiCoO2 at 4.6 V can improve the battery density, however, structural instability is a critical challenge (e.g., electrolyte decomposition, Co dissolution, and structural phase transition). Here, robust electrode electrolyte interphases (EEIs) with the high Li+ conductivity offered by polar amide groups and a Li3N/LiF heterostructure is constructed. 3‐(trifluoromethyl) phenyl isocyanate (3‐TPIC) is rationally designed as an electrolyte additive for sustaining a 4.6 V Li||LiCoO2 battery with such CEI, which can effectively address the challenge of structural instability. The polar amide group can achieve Li+ de‐solvation and increase Li+ transport. Li3N/LiF heterostructure in the cathode electrolyte interphase (CEI) can speed up the Li+ insertion/extraction for improving Coulombic efficiency and weakening polarization of LiCoO2 at 4.6 V. In addition, the solid electrolyte interphase (SEI) with a similar structure on the Li anode surface contributes to the uniform Li deposition for suppressing the Li dendrite growth. As expected, 4.6 V Li||LiCoO2 batteries with superior EEIs can deliver excellent electrochemical performance.

Quasi-Solid Polymer Electrolyte with Multiple Lithium-Ion Transport Pathways by In Situ Thermal-Initiating Polymerization.

Solid polymer electrolytes (SPEs) are considered to be attractive candidates for rechargeable batteries on account of their high safety and flexible processability. However, the restricted polymer segmental dynamics limit the Li+ conduction of SPEs. Herein, a composite electrolyte membrane was prepared via in situ thermal-initiating polymerization of diethylene glycol diacrylate (DEGDA) in a poly(vinylidene fluoride) frameworks (PVDF FMs) electrospun in advance. As a quasi-solid polymer electrolyte (QSPE), it provides multiple transport highways for Li+ built by the C═O or C-O or C═O/C-O groups in poly(diethylene glycol) diacrylate (PDEGDA), respectively, proved by density functional theory calculations together with the high-resolution 7Li solid-state nuclear magnetic resonance spectra. Since the interaction between Li+ and C═O is weaker than that between Li+ and C-O, Li+ tends to move along C═O dominating paths in PDEGDA/PVDF FMs QSPEs, even skipping back to C═O nodes from the original C-O dominating way. Multiple transport patterns facilitate Li+ migration within PDEGDA/PVDF FMs QSPEs, contributing to the ionic conductivity of 1.41 × 10-4 S cm-1 at 25 °C and the Li+ transference number of 0.454. Ascribing to the wetting capability of the monomer to the electrodes in use, compatible electrolyte/electrode interfaces with low interface resistance and compact cells were acquired by the in situ polymerization. Protective lithiated oligomers (RCOOLi) and LiF are enriched at the Li anode surface, promoting a lasting stable Li plating/stripping over 2000 h. By applying the QSPEs in LiFePO4 cell, a capacity of 157.7 mAh g-1 with almost 100% coulombic efficiency during 200 cycles is achieved at 25 °C.