Molecular Adsorption-Induced Interfacial Solvation Regulation to Stabilize Graphite Anode in Ethylene Carbonate-Free Electrolytes

Many organic solvents have excellent solution properties, but fail to serve as lithium-ion batteries (LIBs) electrolyte solvents, due to their electrochemical incompatibility with graphite anodes. Herein, a new strategy is proposed to address this issue by introducing a surface-adsorbed molecular layer to regulate the interfacial solvation structure without the alteration of electrolyte composition and properties. As a proof-of-concept study, it is demonstrated for the first time that the intrinsically incompatible propylene carbonate (PC)-based electrolyte becomes completely compatible with graphite anodes by introducing a layer of adsorbed hexafluorobenzene (HFB) molecules to weaken the Li⁺-PC coordination strength and facilitate the interfacial desolvation process. As a consequence, the graphite/ NCM811 pouch cells using the PC-based electrolyte containing only 1 vol.% HFB demonstrate excellent long-term cycling stabilities over 1150 cycles. This strategy is also proved to be applicable to other ethylene carbonate (EC)–free electrolytes, thus providing a new avenue for developing advanced LIB electrolytes.     

Energy Saving Electrochromic Polymer Windows with a Highly Transparent Charge‐Balancing Layer

Highly transparent TiO₂ nanoparticles are explored as a non‐electrochromic (non‐EC) charge‐balancing layer for a high color contrast, bistable electrochromic window (ECW). The TiO₂ nanoparticle (TNP) layer increases the potential at the EC polymer electrode, thereby lowering the working voltage of the ECW. This leads to lower the power consumption of ECWs without loss in the high color contrast (ΔT > 72%) and to remarkably improve the cyclability (ΔT change <1% over 3000 cycles), mainly due to the low overvoltage (<0.1 V) on the electrochromic polymer layer. Furthermore, the ECWs including the non‐EC TNP layer show long‐term bistability (>2.7 h, 40% increase) and UV stability (ΔT change <1%) to provide a low‐power automatic ECW. This finding shows that the charge balanced ECP window has the potential to be used for an energy saving ECW with low‐power consumption and will be widely applied in various ECWs as well as electrochemical devices with multiple functions.     

Effects of using multi‐component electrolytes on the stability and properties of solar cells sensitized with simple organic dyes

In this paper we present experimental results for electrochemical (dye‐sensitized) solar cells that were prepared in our laboratory in order to examine some of the major factors affecting the efficiency and the stability of such cells. Nanostructured TiO₂ thin films were prepared and sensitized using an organic dye. For the purpose of this study three different types of electrolytes were developed: a standard‐type electrolyte containing potassium iodide and iodine in propylene carbonate (PC) and two novel, multi‐component electrolytes containing potassium iodide and iodine dissolved in varying mixtures of PC and EG (ethylene glycol). It was demonstrated that the combined properties of the two solvents in the multi‐component electrolytes enhance the efficiency and improve considerably the stability of the cells. Copyright © 2010 John Wiley & Sons, Ltd.     

Nonpolar Cosolvent Driving LUMO Energy Evolution of Methyl Acetate Electrolyte to Afford Lithium-Ion Batteries Operating at −60 °C

The operation of lithium-ion batteries (LIBs) at low temperatures (<−20 °C) is hindered by the low conductivity and high viscosity of conventional carbonate electrolytes. Methyl acetate (MA) has proven to be a competitive low-temperature electrolyte solvent with low viscosity and low freezing point, but its interfacial stability is poor and remains elusive until now. Here, it is revealed thaat the reductive stability of MA-based electrolytes is fundamentally governed by the anion-prevailed solvation structure. Based on this framework, fluorobenzene is employed in the electrolyte to promote the entry of anions into the solvation shell via dipole-dipole interactions and the generation of free MA, thus enhancing the lowest unoccupied molecular orbital energy of MA. The designed electrolyte enables LiCoO₂ (LCO)/graphite cells to exhibit excellent cycling performance at −20 °C (90% retention after 1000 cycles at 1 C) and to remain 91% of their room-temperature capacity at a super-low temperature of −60 °C at 0.05 C. Thanks to the plentiful free MA, this electrolyte has a high conductivity (2.61 mS cm⁻¹) at −60 °C and allows LCO/graphite cell to charge at −60 °C. This study offers the possibility of practical applications for those solvents with poor reductive stability and provides new approaches to designing advanced electrolytes for low-temperature applications.     

Design of Fire-Resistant Liquid Electrolyte Formulation for Safe and Long-Cycled Lithium-Ion Batteries

Turning an unsafe material into a safe one without performance loss for Li-ion battery applications provides opportunities to create a new class of materials. Herein, this strategy is utilized to design a fire-resistant liquid electrolyte formulation consisting of propylene carbonate and 2,2,2-trifluoroethyl group-containing linear ester solvents paired with 1 m LiPF₆ salt and fluoroethylene carbonate additive for a Li–ion battery with improved safety and performance. Traditional carbonate-based electrolytes offer good performance in mild operating conditions, but are however a flammable fuel causing fire and safety hazards. It is shown that the entire replacement of linear carbonate with fluorinated linear ester yields a fire-resistant and outperforming electrolyte under the harsh condition of 4.5 V high-voltage, 45 °C and 2C rate, enabling a higher energy, longer cycle life of 500 cycles, faster charged practical graphite‖NCM622 full-cell than traditional electrolyte-based cell. The strong correlation between cathode–electrolyte and anode–electrolyte interfacial stabilization and highly reversible cycling performance is clearly demonstrated. The fire-resistant electrolyte-incorporated industrial 730 mAh graphite‖NCM811 Li-ion pouch battery achieves 82% retention after 400 cycles under 4.3 V charge voltage, 45 °C and 1C, and markedly improved safety on overcharge abuse tests. The design strategy for electrolyte formulation provides a promising path to safe and long-cycled high-energy Li-ion batteries.     

Dilute Aqueous Hybrid Electrolyte with Regulated Core-Shell-Solvation Structure Endows Safe and Low-Cost Potassium-Ion Energy Storage Devices

High-concentration “water-in-salt” (WIS) electrolytes with the wider electrochemical stability window (ESW) can give rise to safe, non-flammable, and high-energy aqueous potassium-ion energy storage devices, thus highlighting the prospect for applications in grid-scale energy storage. However, WIS electrolytes usually depend on highly concentrated salts, leading to serious concerns about cost and sustainability. Here, an aqueous low-concentration-based potassium-ion hybrid electrolyte is demonstrated with the regulated core-shell-solvation structure by using an aprotic solvent, i.e., trimethyl phosphate, to limit the water activity. This aqueous hybrid electrolyte has a low salt concentration (1.6 mol L⁻¹) of potassium trifluoromethanesulfonate but with an expanded ESW up to 3.4 V and the nonflammable property. Based on this dilute aqueous hybrid electrolyte, electrochemical double-layer capacitors are capable of working within a large voltage range (0–2.4 V) at a wide range of temperatures from −20 to 60 °C. An aqueous potassium-ion battery consisting of an organic 3,4,9,10-perylenetetracarboxylic diimide anode, Prussian blue K_1.5Mn_0.61Fe_0.39[Fe(CN)₆]_0.77·H₂O cathode and this dilute aqueous hybrid electrolyte can operate well at rates between 0.2 and 4.0 C and deliver a high energy density of 66.5 Wh kg⁻¹ as well as a durable cycling stability with a capacity retention of 84.5% after 600 cycles at 0.8 C.     

Tuning Electrolyte Solvation Structure and CEI Film to Enable Long Lasting FSI−-Based Dual-Ion Battery

Dual-ion battery (DIB) is a promising energy storage system because it can provide high power. However, the stability and rate performance of the battery depend strongly on the type of salt and solvents in the electrolyte. Herein, the use of lithium bis(fluorosulfonyl)imide (LiFSI) is studied, which has better high-temperature stability, as salt in the DIB and develop a 3 m  LiFSI fluoroethylene carbonate/methyl 2,2,2-trifluoroethyl carbonate (FEC/FEMC) = 3:7 electrolyte, which stabilizes graphite–lithium DIB with 94.1% capacity retention after 2000 cycles at 5C. The DIB also exhibits excellent rate performance with 100.4 mAh g⁻¹ capacity at 30C, with a utilization of 96.3% compared to capacity at 2C. The outstanding electrochemical performance is attributed to the thin cathode electrolyte interface (CEI) layer and fast FSI⁻ transport kinetics, confirmed by X-ray photoelectron spectroscopy and activation energy calculation. Superior cycle and rate performances are also obtained from a graphite–graphite full cell. Though, increasing salt concentration to 5 and 6 m leads to sluggish FSI⁻ de-intercalation reaction and lower capacity, which is attributed to solvent co-intercalation. The research suggests that the electrolyte plays an important role in ion transport, surface film formation, and stability of DIB.     

A Dilute Fluorinated Phosphate Electrolyte Enables 4.9 V-Class Potassium Ion Full Batteries

Potassium ion batteries using graphite anode and high-voltage cathodes are considered to be optimizing candidates for large-scale energy storage. However, the lack of suitable electrolytes significantly hinders the development of high-voltage potassium ion batteries. Herein, a dilute (0.8 m ) fluorinated phosphate electrolyte is proposed, which exhibits extraordinary compatibility with both graphite anode and high-voltage cathodes. The phosphate solvent, tris(2,2,2-trifluoroethyl) phosphate (TFP), has weak solvating ability, which not only allows the formation of robust anion-derived solid electrolyte interphase on graphite anode but also effectively suppresses the corrosion of Al current collector at high voltage. Meanwhile, the high oxidative stability of fluorinated TFP solvent enables stable ultrahigh-voltage (4.95 V) cycling of a potassium vanadium fluorophosphate (KVPO₄F) cathode. Using TFP-based electrolyte, the 4.9 V-class potassium ion full cell based on graphite anode and KVPO₄F cathode shows rather remarkable cycling performance with a high capacity retention of 87.2% after 200 cycles. This study provides a route to develop dilute electrolytes for high-voltage potassium ion batteries, by utilizing solvents with both weak solvating ability and high oxidative stability.     

Catalytically Induced Robust Inorganic-Rich Cathode Electrolyte Interphase for 4.5 V Li||NCM622 Batteries

Tailoring inorganic components of cathode electrolyte interphase (CEI) and solid electrolyte interphase (SEI) is critical to improving the cycling performance of lithium metal batteries. However, it is challenging due to complicated electrolyte reactions on cathode/anode surfaces. Herein, the species and inorganic component content of the CEI/SEI is enriched with an objectively gradient distribution through employing pentafluorophenyl 4-nitrobenzenesulfonate (PFBNBS) as electrolyte additive guided by engineering bond order with functional groups. In addition, a catalytic effect of LiNi_0.6Mn_0.2Co_0.2O₂ (NCM622) cathode is proposed on the decomposition of PFBNBS. PFBNBS with lower highest occupied molecular orbital can be preferentially oxidized on the NCM622 surface with the help of the catalytic effect to induce an inorganic-rich CEI for superior electrochemical performance at high voltage. Moreover, PFBNBS can be reduced on the Li surface due to its lower lowest unoccupied molecular orbital , increasing inorganic moieties in SEI for inhibiting Li dendrite generation. Thus, 4.5 V Li||NCM622 batteries with such electrolyte can retain 70.4% of initial capacity after 500 cycles at 0.2 C, which is attributed to the protective effect of the excellent CEI on NCM622 and the inhibitory effect of its derived CEI/SEI on continuous electrolyte decomposition.     

Unlocking the Potential of Lithium Metal Batteries With a Sulfite-Based Electrolyte

Lithium metal batteries (LMBs) have the potential to significantly increase the energy density of advanced batteries in the future. Nonetheless, the dendritic lithium structures and low Coulombic efficiency (CE) of LMBs currently impede their applied implementation. Herein, a sulfite-based electrolyte (SBE/FEC), including 1.0 m lithium bis(fluorosulfonyl)imide in a blend of ethylene sulfite and diethyl sulfite, and 5 wt% fluoroethylene carbonate is proposed. SBE/FEC is a highly efficient inhibitor against the growth of lithium dendrites through the formation of robust solid electrolyte interphase (SEI) layer. Raman spectroscopy and theoretical calculation indicate that in SBE/FEC, a significant portion of FSI⁻ exists in associated complexes, playing a vital role in the creation of LiF-rich passivation. Besides, the sulfite solvents decompose and yield polysulfide complexes in the SEI layer. A direct correlation between the proportion of cation–anion complexes and the contact angle between electrolyte and separator is elucidated through molecular dynamics simulations. The SBE/FEC system exhibits high CEs (98.3%) with Li||Cu cells, along with a steady discharge capacity of ≈137 mA h g⁻¹ in Li||LiFePO₄ cell. This study presents an effective approach for enhancing LMBs with sulfite-based electrolytes, which can lead to high-energy-density next-generation rechargeable batteries.     

Fluoride-Rich Solid-Electrolyte-Interface Enabling Stable Sodium Metal Batteries in High-Safe Electrolytes

Sodium metal batteries (SMBs) are promising for large scale energy storage due to the remarkable capacity of sodium metal anode (SMA) and the natural abundance of Na-containing resources. However, multiple challenges exist with regards to the usage of SMBs, including dendritic Na growth, poor cyclability of SMA, and severe safety hazards stemming from the employment of the highly flammable liquid electrolytes. Herein, by introducing two functional fluorinated solvents, 1,1,2,2-tetra-fluoroethyl 2,2,3,3-tetrafluoropropyl ether (HFE) and fluoroethylene carbonate (FEC) into trimethyl phosphate (TMP)-based electrolyte, a SMA-compatible flame-retardant electrolyte is enabled, in which Na/Na symmetrical cells can cycle for 800 h at 1.0 mA cm⁻² or 3.0 mAh cm⁻². Specifically, the non-solvating HFE plays a critical role in increasing the local electrolyte concentration and reducing the unfavorable decomposition of TMP molecules. By introducing FEC as the co-solvent simultaneously, its preferential defluorination induces a fluoride-rich solid-electrolyte interphase that prevents Na metal surface against the continuous parasitic reactions. More importantly, the designed electrolyte is endowed with an intrinsic non-flammability, which manifests a prerequisite for the real-life application of SMBs.     

Engineering Solid Electrolyte Interphase for Pseudocapacitive Anatase TiO2 Anodes in Sodium‐Ion Batteries

Anatase TiO₂ is considered as one of the promising anodes for sodium‐ion batteries because of its large sodium storage capacities with potentially low cost. However, the precise reaction mechanisms and the interplay between surface properties and electrochemical performance are still not elucidated. Using multimethod analyses, it is herein demonstrated that the TiO₂ electrode undergoes amorphization during the first sodiation and the amorphous phase exhibits pseudocapacitive sodium storage behaviors in subsequent cycles. It is also shown that the pseudocapacitive sodium storage performance is sensitive to the nature of solid electrolyte interphase (SEI) layers. For the first time, it is found that ether‐based electrolytes enable the formation of thin (≈2.5 nm) and robust SEI layers, in contrast to the thick (≈10 nm) and growing SEI from conventional carbonate‐based electrolytes. First principle calculations suggest that the higher lowest unoccupied molecular orbital energies of ether solvents/ion complexes are responsible for the difference. TiO₂ electrodes in ether‐based electrolyte present an impressive capacity of 192 mAh g^?1 at 0.1 A g^?1 after 500 cycles, much higher than that in carbonate‐based electrolyte. This work offers the clarified picture of electrochemical sodiation mechanisms of anatase TiO₂ and guides on strategies about interfacial control for high performance anodes.     

Dynamic Networks of Cellulose Nanofibrils Enable Highly Conductive and Strong Polymer Gel Electrolytes for Lithium-Ion Batteries

Tunable dynamic networks of cellulose nanofibrils (CNFs) are utilized to prepare high-performance polymer gel electrolytes. By swelling an anisotropically dewatered, but never dried, CNF gel in acidic salt solutions, a highly sparse network is constructed with a fraction of CNFs as low as 0.9%, taking advantage of the very high aspect ratio and the ultra-thin thickness of the CNFs (micrometers long and 2–4 nm thick). These CNF networks expose high interfacial areas and can accommodate massive amounts of the ionic conductive liquid polyethylene glycol-based electrolyte into strong homogeneous gel electrolytes. In addition to the reinforced mechanical properties, the presence of the CNFs simultaneously enhances the ionic conductivity due to their excellent strong water-binding capacity according to computational simulations. This strategy renders the electrolyte a room-temperature ionic conductivity of 0.61 ± 0.12 mS cm⁻¹ which is one of the highest among polymer gel electrolytes. The electrolyte shows superior performances as a separator for lithium iron phosphate half-cells in high specific capacity (161 mAh g⁻¹ at 0.1C), excellent rate capability (5C), and cycling stability (94% capacity retention after 300 cycles at 1C) at 60 °C, as well as stable room temperature cycling performance and considerably improved safety compared with commercial liquid electrolyte systems.     

Ion-Conducting Non-Flammable Liquid Crystal–Polymer Composites for High-Frequency Soft Actuators

High-frequency actuators are reported based on non-flammable lithium-ion conducting phosphate liquid crystal–polymer composite electrolytes, which exhibit a bending response at frequencies up to 80 Hz under an AC voltage of 2 V, owing to its high ionic conductivity reaching 10⁻⁴ S cm⁻¹ at room temperature. An equimolar complex of a phosphate-containing mesogenic molecule and lithium bis(trifluoromethylsulfonyl)imide through the ion-dipole interactions induced a room-temperature smectic A liquid-crystalline (LC) phase forming 2D ion-transport pathways comprising the 2D array of the phosphate moieties. A blend of 80 wt% LC electrolyte and 20 wt% polymers (poly(vinyl chloride) and poly(vinylidene fluoride-co-hexafluoropropylene)) formed a flexible, mechanically robust LC–polymer composite film. Scanning electron microscopy and white light interference microscopy revealed a microphase-segregated structure consisting of a continuous LC phase and a porous polymer matrix. In addition, the continuity of porous structure across the film is confirmed by permeation experiments of solvents thorough the membrane with a homemade filter in a dead-end filtration mode. The LC–polymer composite film sandwiched between two poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) electrodes is found to simultaneously exhibit high bending strain (0.63%) and high output force (0.35 mN), owing to the high ion migration into the composite electrolyte and electrode.     

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

The 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 LiNi_0.8Co_0.15Al_0.05O₂ (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.     

Open-circuit voltage exceeding the outermost HOMO-LUMO offset in cascade organic solar cells

We demonstrate a planar organic solar cell with a four-layer cascade architecture that exhibits an open-circuit voltage (Voc) greater than the offset in energy between the highest occupied molecular orbital (HOMO) of the outermost donor and the lowest unoccupied molecular orbital (LUMO) of the outermost acceptor. The device consists of a subphthalocyanine (SubPc)/fullerene (C60) heterojunction that is modified by inserting one or two additional donor layers between SubPc and the anode. We find that two-, three- and four-layer structures yield similar Voc (1.0 V, 0.91 V and 0.94 V, respectively), even though the outermost HOMO-LUMO offset decreases from 1.4 eV to 1.10 eV, and to 0.9 eV, respectively. Analysis of the turn-on voltage in dark provides further evidence that open-circuit voltage is not limited by the outermost HOMO-LUMO offset.     

An Intrinsically Nonflammable Electrolyte for Prominent-Safety Lithium Metal Batteries with High Energy Density and Cycling Stability

Nex-generation high-energy-density storage battery, assembled with lithium (Li)-metal anode and nickel-rich cathode, puts forward urgent demand for advanced electrolytes that simultaneously possess high security, wide electrochemical window, and good compatibility with electrode materials. Herein an intrinsically nonflammable electrolyte is designed by using 1 M lithium difluoro(oxalato)borate (LiDFOB) in triethyl phosphate (TEP) and N-methyl-N-propyl-pyrrolidinium bis(trifluoromethylsulfonyl)imide [Pyr₁₃][TFSI] ionic liquid (IL) solvents. The introduction of IL can bring plentiful organic cations and anions, which provides a cation shielding effect and regulates the Li⁺ solvation structure with plentiful Li⁺-DFOB⁻ and Li⁺-TFSI⁻ complexes. The unique Li⁺ solvation structure can induce stable anion-derived electrolyte/electrode interphases, which effectively inhibit Li dendrite growth and suppress side reactions between TEP and electrodes. Therefore, the LiNi_0.9Co_0.05Mn_0.05O₂ (NCM90)/Li coin cell with this electrolyte can deliver stable cycling even under 4.5 V and 60 °C. Moreover, a Li-metal battery with thick NCM90 cathode (≈ 15 mg cm⁻²) and thin Li-metal anode (≈ 50 µm) (N/P ≈ 3), also reveals stable cycling performance under 4.4 V. And a 2.2 Ah NCM90/Li pouch cell can simultaneously possess prominent safety with stably passing the nail penetration test, and high gravimetric energy density of 470 Wh kg⁻¹ at 4.4 V.     

Electrolyte‐Regulated Solid‐Electrolyte Interphase Enables Long Cycle Life Performance in Organic Cathodes for Potassium‐Ion Batteries

Organic cathode materials as economical and environment‐friendly alternatives to inorganic cathode materials have attracted comprehensive attention in potassium‐ion batteries (KIBs). Nonetheless, active material dissolution and mismatched electrolytes result in insufficient cycle life that definitely hinders their practical applications. Here, a significantly improved cycle life of 1000 cycles (80% capacity retention) on a practically insoluble organic cathode material, anthraquinone‐1,5‐disulfonic acid sodium salt, is realized, in KIBs through a solid‐electrolyte interphase (SEI) regulation strategy by ether‐based electrolytes. Such an excellent performance is attributed to the robust SEI film and fast reaction kinetics. More importantly, the ether‐electrolyte‐derived SEI film has a protective inorganic‐rich inner layer arising from the prior decomposition of potassium salts to solvents, as revealed by X‐ray photoelectron spectroscopy analysis and computational studies on molecular orbital energy levels. The findings shed light on the critical roles of electrolytes and the corresponding SEI films in enhancing performance of organic cathodes in KIBs.     

Synergistic Solvation of Anion: An Effective Strategy toward Economical High-Performance Dual-Ion Battery

The solvation structure of anion plays a crucial role in determining the performance of dual-ion batteries using graphite-positive electrodes. In past research on dual-ion batteries, the design criteria of electrolyte solutions were largely based on the traditional relationship between solvents and additives. Here, a distinctive synergistic solvation strategy is proposed for the design of electrolyte solutions. Despite some solvents performing poorly or even failing to operate when they are used alone for electrolyte solutions, an unexpected improved performance appears when they are combined based on their characteristic moieties. Based on the synergistic solvation strategy, an economical electrolyte solution system (LiPF₆-methyl acetate/diethyl carbonate) is successfully designed. The intercalation behavior of the solvated anion from this solution into the graphite electrode is investigated by conventional electrochemical tests, in situ electrochemical characterizations and theoretical calculations. A proof-of-concept dual-ion battery based on this electrolyte solution delivers a discharge capacity of 100.08 mAh g⁻¹ and ≈4.67 V medium discharge voltage at 10C (1 A g⁻¹), along with 85.35% capacity retention after 1000 cycles at 5C. Moreover, this battery exhibits 93.8% of its room-temperature capacity at −20 °C and can even work at −70 °C. Synergistic solvation offers a novel approach to design electrolyte solutions for dual-ion batteries.     

Molecular-level Designed Polymer Electrolyte for High-Voltage Lithium–Metal Solid-State Batteries

In solid polymer electrolytes (SPEs) based Li–metal batteries, the inhomogeneous migration of dual-ion in the cell results in large concentration polarization and reduces interfacial stability during cycling. A special molecular-level designed polymer electrolyte (MDPE) is proposed by embedding a special functional group (4-vinylbenzotrifluoride) in the polycarbonate base. In MDPE, the polymer matrix obtained by copolymerization of vinylidene carbonate and 4-vinylbenzotrifluoride is coupled with the anion of lithium-salt by hydrogen bonding and the “σ-hole” effect of the C F bond. This intermolecular interaction limits the migration of the anion and increases the ionic transfer number of MDPE (t_Li⁺ = 0.76). The mechanisms of the enhanced t_Li⁺ of MDPE are profoundly understood by conducting first-principles density functional theory calculation. Furthermore, MDPE has an electrochemical stability window (4.9 V) and excellent electrochemical stability with Li–metal due to the CO group and trifluoromethylbenzene (ph-CF₃) of the polymer matrix. Benefited from these merits, LiNi_0.8Co_0.1Mn_0.1O₂-based solid-state cells with the MDPE as both the electrolyte host and electrode binder exhibit good rate and cycling performance. This study demonstrates that polymer electrolytes designed at the molecular level can provide a broader platform for the high-performance design needs of lithium batteries.