Solid-state, single-ion-conducting, polymer blend electrolytes with improved ionic conductivity

Abstract

The present disclosure provides compositions that include one or more of the following: (i) a glassy single-ion conducting (SIC) polymer containing an anionic moiety chemically bound to the glassy SIC polymer and a mobile cation; (li) a flexible ion¬ conducting polymer blended with or chemically bound to the glassy SIC polymer; and / or (iii) optionally one or more nanoparticles dispersed in or chemically bound to at least one of the glassy SIC polymer and / or the flexible ion-conducting polymer. Electrolytes and devices containing the above compositions are also disclosed.

Description

2101715-001234 -1- SOLID-STATE, SINGLE-ION-CONDUCTING, POLYMER-BLEND ELECTROLYTES WITH IMPROVED IONIC CONDUCTIVITY CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 539, 177, filed September 19, 2023, the entire disclosure of which is incorporated herein by reference for all purposes in its entirety. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

[0002] This invention was made with government support under Grant No. DE- SC0014458 awarded by the Department of Energy. The government has certain rights in the invention. FIELD

[0003] The present disclosure relates to compositions, electrolytes, and devices that contain polymer blends and simultaneously possess improved ionic conductivities, Li+selectivities, and electrochemical stabilities. BACKGROUND

[0004] Lithium-ion batteries (LiBs) are used in electric vehicles, consumer electronics products, and renewable energy storage devices. Several desirable features for the next generation of these devices include faster charging rate, higher power / energy density, and enhanced safety. Current commercial liquid electrolytes, in which binary lithium salts and stabilizing additives are dissolved in flammable liquid solvents, offer high ionic conductivities (about 10-3to 10-2S / cm at -10 to 80 °C) but low Li+transference numbers (tLi+s, typically < 0.5) due to mobility of both the cation and anion. The low tLi+s can lead to the formation of salt concentration gradients that accelerate Li dendrite formation and limit the charging / discharging rate, energy density, and cycling life of the battery. Moreover, many liquid electrolytes are susceptible to solvent leakage, thermal runaway, and eventual battery failure. The above-mentioned concerns can be substantially alleviated through the use of all-solid-state polymer electrolytes (SPEs) that provide both high tLi+and high ionic conductivity. Unfortunately, the inherent trade-off between2101715-001234 -2- transference number and conductivity remains a major challenge in the development of high-performance polymeric materials.

[0005] Most current SPEs are based on polyethylene oxide (PEO). For example, PEO doped with Li bis(trifluoromethanesulfonyl)imide (LiTFSI) has reasonably high ionic conductivity (about 10-3S / cm at 60 to 100 °C), low toxicity, and good thermal stability. The low glass transition temperature (Tg= about -60 °C) of PEO facilitates fast segmental dynamics when the system is amorphous to support ion motion at temperatures well above Tg. However, the high crystallinity of PEO below the melting temperature (Tm,PEO = about 62  °C for 10 to 20 kg / mol) leads to a significant reduction in conductivity near room temperature. There have been numerous studies focused on disrupting crystallinity in PEO using PEO-grafted polymethacrylates and PEO-based copolymers. For instance, poly(oligo- oxyethylene methyl ether methacrylate) (POEM), with its ether-oxygen side chains, has shown promise in terms of significantly improved room-temperature conductivity vs. analogous salt-doped PEO systems when the appropriate side-chain lengths are employed. Other approaches also have been developed to decrease the crystallinity of PEO, including nanoparticle addition, polymer blending, and cross-linking. Additionally, small-molecule plasticization and low-Tgsegment introduction have been shown to accelerate segmental relaxation, and polymer architecture modification can effectively alter the Li+-polymer coordination and / or the Li+solvation-site connectivity. Although improved overall conductivities have been achieved, the significant anion motion in these PEO-based electrolytes results in low tLi+s (about 0.2), and therefore relatively modest Li+conductivities (about 10-4S / cm at 60 to 100 °C).

[0006] Apart from modest Li+conductivities in PEO-based electrolytes, low tLi+s also limit electrochemical windows in these systems by accelerating the irreversible anion oxidation or reduction near the electrode, and therefore, decreasing the electrochemical stabilities of SPEs. The benchmark LiTFSI-doped PEO (PEO / LiTFSI) system has a low electrochemical stability (about 3.5 V vs. about 4.2 V for liquid electrolytes against Li+ / Li), which is not suitable for using energy-dense anodes such as Li metal in batteries. The widely adopted strategies for improving electrochemical stabilities of PEO-based SPEs include introducing another high voltage-resistant SPE or inorganic component and constructing kinetically stable interfaces at the electrode surface. End-group modification also has shown promise in widening the electrochemical stability windows. Although2101715-001234 -3- improved electrochemical stabilities have been realized (about 4.0 to 4.3 V against Li+ / Li), decreased overall conductivities are seen in some systems in comparison to the benchmark PEO / LiTFSI system.

[0007] SPEs with low tLi+s also limit relative improvements in another important parameter, i.e., limiting current density. The limiting current density dictates the largest sustainable current density that can be passed through the electrolytes, with higher values indicative of more rapid charging of the battery. In SPEs with significant anion motion (low tLi+s), the gradual buildup of a salt concentration polarization leads to Li+depletion at the cathode and therefore lower limiting current densities. It has been reported that the variation in Li+solvation environment can lead to improved limiting current densities in comparison to PEO / LiTFSI by about 2.8 fold but at the cost of almost an order-of-magnitude decrease in overall conductivities.

[0008] The challenges associated with low tLi+s in polymers can be largely addressed through immobilization of the anions, i.e., rendering the electrolytes as single- ion-conducting (SIC). SIC polymers typically have relatively high Tgs (> 60 °C), resulting in significantly limited segmental relaxation to support rapid Li+transport in comparison to PEO-based electrolytes (Tg= about -60 °C). Moreover, the inherently strong electrostatic interactions between the anion and Li+lead to insufficient free Li+concentrations, thereby reducing conductivities. Both features lead to low conductivities in SIC homopolymers (about 10-8to 10-6S / cm at 200 °C). To date, various approaches have been adopted to enhance the conductivities of solid-state SIC polymer electrolytes, for example, copolymerizing or blending with a low-Tg, ion-solvating polymer, such as PEO (Tg = about -60 °C), PEO-derivative, or polyvinylidene fluoride (Tg= about -35 °C). However, the conductivities of all-solid-state SIC polymer electrolytes have been relatively modest, plateauing at about 10-5to 10-4S / cm at 90 to 110 °C.

[0009] The limited conductivities are attributed to the inherent anticorrelation between fast segmental relaxation and sufficient free Li+. Promising conductivities (e.g., about 10-3S / cm) that may support many battery applications typically are only achieved in solvent-plasticized systems at the potential cost of battery safety and electrochemical stability. The above-mentioned systems usually consist of either low ion concentrations (molar ratio between coordinating groups and ions of about 20:1) and / or low (about 4 to 8 kg / mol) to intermediate (about 10 to 30 kg / mol) molecular-weight polymer(s), rendering2101715-001234 -4- these systems ‘soft’ and making them prone to pack space relatively tightly / efficiently. Thus, ion diffusion in these soft systems is possible only when polymer segmental relaxation occurs. Although restricted anion motion (high tLi+s) typically is expected to improve electrochemical stabilities (e.g., 4.6 to 7.0 V) and limit current densities (seldom reported for SIC SPEs), one conundrum in these systems is that fast segmental dynamics requires relatively low Li+concentration to reduce Tgsuppression, whereas sufficient amount of free Li+is crucial to enhance conductivities. This inherent anticorrelation remains the major challenge in the development of solid-state SIC systems that simultaneously exhibit high conductivities, Li+selectivities, electrochemical stabilities, and limiting current densities.

[0010] There have been a few successful reports on decoupling Li+diffusion from segmental dynamics to address this inherent anticorrelation in SIC polymer electrolytes. For example, in a copolymer system consisting of (ethylene glycol) methyl ether acrylate and lithium 3-[(trifluoromethane) sulfonamidosulfonyl]propyl methacrylate, the percolating and locally dynamic ionic aggregates supported Li+transport. The highest conductivities (about 10-3S / cm at 150 °C) in this system were comparable to PEO / LiTFSI. Other reports have focused on zwitterionic polymer-based electrolytes in which Li+hopped within the liquid- like electrolytes. The overall conductivities (about 10-4to 10-3S / cm at 80 to 110 °C) were comparable to PEO / LiTFSI with improved Li+selectivities (tLi+s = 0.6 to 0.8) and electrochemical stabilities (3.8 V against Li+ / Li).

[0011] Though there have been few successful reports on decoupling Li+diffusion from segmental dynamics to address the inherent anticorrelation in SIC polymer electrolytes, there is still a need for SPE electrolyte compositions that simultaneously exhibit high ionic conductivities, Li+selectivities, and electrochemical stabilities. SUMMARY

[0012] Disclosed herein are compositions that includes (i.e., comprises) one or more of the following: (i) a glassy single-ion-conducting (SIC) polymer containing an anionic moiety chemically bound to the SIC polymer and a mobile cation; (ii) a flexible ion- conducting polymer blended with or chemically bound to the SIC polymer, wherein the flexible ion-conducting polymer contains oxygen, fluorine, sulfur, nitrogen, or phosphorous-based moieties in a backbone and / or side chains of the flexible ion-conducting2101715-001234 -5- polymer; and / or (iii) optionally one or more nanoparticles dispersed in or chemically bound to at least one of the glassy SIC polymer and / or the flexible ion-conducting polymer.

[0013] Disclosed herein are also solid-state electrolytes including any one of the compositions disclosed herein.

[0014] Disclosed herein are also devices that include one or more of the following: an anode, a cathode, and / or any one of the solid-state electrolytes disclosed herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features and advantages of the compositions, devices, and methods disclosed herein will be apparent to those skilled in the art reading the following detailed description in conjugation with the exemplary embodiments illustrated in the drawings, wherein:

[0016] FIG.1 depicts the Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy of an exemplary poly(oligo-oxyethylene methyl ether methacrylate) (POEM).1H NMR spectroscopy experiments were run on a Bruker AV600III instrument using chloroform-d (0.03% v / v tetramethylsilane) as the solvent.1H NMR (chloroform-d, 600 MHz, δ) for POEM: 4.08 (2H, t), 3.65 (32H, t), 3.38 (3H, t).

[0017] FIG.2 depicts the1H NMR spectrum of an exemplary poly[lithium sulfonyl(trifluoromethane sulfonyl)imide methacrylate] (PLiMTFSI).1H NMR spectroscopy experiments were run on a Bruker AV600III instrument using acetone-d6 (0.03% v / v tetramethylsilane) as the solvent.1H NMR (acetone-d6, 600 MHz, δ) for PLiMTFSI: 4.18 (2H, t), 3.27 (2H, qt), 2.22 (2H, t).

[0018] FIG.3 depicts the Size Exclusion Chromatography (SEC) traces of exemplary POEM and PLiMTFSI homopolymers.

[0019] FIG.4 depicts the shear storage modulus (G′) for (a) neat PLiMTFSI – 52 and (b) neat POEM. Master curves are constructed using time-temperature superposition at a reference temperature of 60 °C.

[0020] FIG.5 depicts G′ for an exemplary PLiMTFSI – 52 / POEM having a [EO]:[Li] ratio (denoted as ‘r’) of 10:1. Master curve is constructed using time-temperature superposition at a reference temperature of 60 °C.

[0021] FIG.6 depicts the ionic conductivities of exemplary polymer blends as a function of 1000 / T. The composition of each blend electrolyte was denoted as2101715-001234 -6- ‘PLiMTFSI−X / POEM’ in which X represents the number-average molecular weight of PLiMTFSI (Mn,PLiMTFSI) in kg / mol. (a) Ionic conductivities of various PLiMTFSI / POEM polymer blends having an r of 5:1. (b) Ionic conductivities of various PLiMTFSI / POEM polymer blends having an r of 10:1. (c) Ionic conductivities of various PLiMTFSI / POEM polymer blends having an r of 20:1. (d) Ionic conductivities of various PLiMTFSI / POEM polymer blends having an r of 30:1. Vogel−Tammann−Fulcher (VTF)-like fits to conductivities are shown by dashed lines; Arrhenius-like fits to conductivities are shown by solid lines. The error bars (most of which are smaller than the data points) represent the standard deviations from averaging of 5-min and 8-min impedance measurements.

[0022] FIG.7 depicts the alternating current (AC) impedance spectroscopy results of an exemplary electrolyte polymer blend PLiMTFSI – 52 / POEM, r = 10:1. (a) Overall ionic conductivities (data points) and Arrhenius-like fits (lines) as a function of 1000 / T for one cell using aluminum blocking electrodes (filled data points and line) and three replicate cells using lithium non-blocking electrodes (hollow data points and lines). The error bars represent the standard deviations from averaging the 5-min and 8-min impedance measurements. (b) Imaginary impedance (Z′′) as a function of the real impedance (Z′) for one cell using aluminum blocking electrodes (filled data points) and three replicate cells using lithium non-blocking electrodes (hollow data points) at 60 ^C. (c) Real impedance (Z′) as a function of the AC frequency for one cell using aluminum blocking electrodes (filled data points) and three replicate cells using lithium non-blocking electrodes (hollow data points) at 60 ^C.

[0023] FIG.8 depicts the ionic conductivities of exemplary polymer blends as a function of r, Mn,PLiMTFSI, and 1000 / T. (a) Ionic conductivities of various PLiMTFSI / POEM polymer blends with different rs and Mn,PLiMTFSIs at 60 °C. (b) Ionic conductivities of various PLiMTFSI / POEM polymer blends with different rs and Mn,PLiMTFSIs at 90 °C. (c) Comparison of temperature-dependent overall ionic conductivities for PLiMTFSI – 52 / POEM, r = 10:1 (filled squares, fit to the Arrhenius equation shown by a solid line) vs. LiTFSI-doped PEO (hollow triangles) and LiTFSI-doped POEM (hollow circles). (d) Comparison of temperature-dependent Li+conductivities for PLiMTFSI – 52 / POEM, r = 10:1 (filled squares, fit to the Arrhenius equation shown by a solid line) vs. LiTFSI-doped PEO (hollow triangles) and LiTFSI-doped POEM (hollow circles). The error bars (most of2101715-001234 -7- which are smaller than the data points) represent the standard deviations from averaging of 5-min and 8-min impedance measurements.

[0024] FIG.9 depicts AC impedance spectroscopy results of Cell 1 with an exemplary PLiMTFSI – 52 / POEM electrolyte blend having an r of 10:1. (a) Z′′ as a function of Z′ for the expanded view of Cell 1 (see Table 2) before polarization. (b) Z′ as a function of the AC frequency for Cell 1 before polarization. (c) Z′′ as a function of Z′ for the expanded view of Cell 1 after polarization. (d) Z′ as a function of the AC frequency for Cell 1 after polarization.

[0025] FIG.10 depicts AC impedance spectroscopy results of Cell 2 with an exemplary PLiMTFSI – 52 / POEM electrolyte blend having an r of 10:1. (a) Z′′ as a function of Z′ for the expanded view of Cell 2 (see Table 2) before polarization. (b) Z′ as a function of the AC frequency for Cell 2 before polarization. (c) Z′′ as a function of Z′ for the expanded view of Cell 2 after polarization. (d) Z′ as a function of the AC frequency for Cell 2 after polarization.

[0026] FIG.11 depicts AC impedance spectroscopy results of Cell 3 with an exemplary PLiMTFSI – 52 / POEM electrolyte blend having an r of 10:1. (a) Z′′ as a function of Z′ for the expanded view of Cell 3 (see Table 2) before polarization. (b) Z′ as a function of the AC frequency for Cell 3 before polarization. (c) Z′′ as a function of Z′ for the expanded view of Cell 3 after polarization. (d) Z′ as a function of the AC frequency for Cell 3 after polarization.

[0027] FIG.12 depicts AC impedance spectroscopy results of Cell 4 with an exemplary PLiMTFSI – 52 / POEM electrolyte blend having an r of 10:1. (a) Z′′ as a function of Z′ for the expanded view of Cell 4 (see Table 2) before polarization. (b) Z′ as a function of the AC frequency for Cell 4 before polarization. (c) Z′′ as a function of Z′ for the expanded view of Cell 4 after polarization. (d) Z′ as a function of the AC frequency for Cell 4 after polarization.

[0028] FIG.13 depicts the ionic conductivities for an exemplary PLiMTFSI – 16 / POEM blend electrolyte. (a) Ionic conductivities (data points) and fit (solid line) as a function of angular frequency for an exemplary PLiMTFSI – 16 / POEM blend electrolyte (r = 5:1). (b) Ionic conductivities (filled data points) and ion hopping times (hollow data points) as a function of Mn,PLiMTFSI at 60 °C for exemplary PLiMTFSI – 16 / POEM blend electrolytes (r = 5:1 and 10:1). (c) Ionic conductivities (filled data points) and ion hopping2101715-001234 -8- times (hollow data points) as a function of Mn,PLiMTFSI at 60 °C for exemplary PLiMTFSI – 16 / POEM blend electrolytes (r = 20:1 and 30:1). The error bars for the conductivity data in (b) and (c), most of which are smaller than the data points, represent the standard deviations from averaging of 5-min and 8-min impedance measurements.

[0029] FIG.14 depicts the ion hopping times for exemplary PLiMTFSI – 16 / POEM blend electrolytes. Overall ionic conductivities (filled squares and diamonds) and ion hopping times (hollow squares and diamonds) as a function of Mn,PLiMTFSI for polymer blend electrolytes having an r of 5:1 and 10:1 at (a) 90 °C and (b) 110 °C, and for polymer blend electrolytes having an r of 20:1 and 30:1 at (c) 90 °C and (d) 110 °C. The lines between data points are to guide the eye. The error bars for the conductivity data represent the standard deviations from averaging the 5-min and 8-min impedance measurements.

[0030] FIG.15 depicts the Tg, the heat capacity change of PLiMTFSI at Tg(ΔCp,PLiMTFSI), and the Gordon−Taylor equationfitting parameter (k) for various PLiMTFSIsand exemplary polymer blends. (a) Tg of neat PLiMTFSI (Tg,PLiMTFSI) plotted as a function of 1 / Mn,PLiMTFSI. (b) Tg,PLiMTFSIplotted as a function of Mn,PLiMTFSI. Fits to the Fox-Flory equation are shown as the solid line. (c) ΔCp,PLiMTFSI plotted as a function of Mn,PLiMTFSI. (d) ΔCp,PLiMTFSI× Tg,PLiMTFSIplotted as a function of Mn,PLiMTFSI. (e) The polymer blend electrolyte Tg (Tg,blend, data points) and fits to Gordon–Taylor equation (dashed lines) for exemplary PLiMTFSI – 7 / POEM polymer blend electrolytes (circles), exemplary PLiMTFSI – 16 / POEM polymer blend electrolytes (triangles), exemplary PLiMTFSI – 25 / POEM polymer blend electrolytes (diamonds), exemplary PLiMTFSI – 52 / POEM polymer blend electrolytes (squares), and exemplary PLiMTFSI – 105 / POEM (crosses) polymer blend electrolytes. (f) k plotted as a function of Mn,PLiMTFSI. The error bars in (a), (b), (c), (d), and (e), most of which are smaller than the data points, represent the standard deviations from averaging the values obtained from a second and third differential scanning calorimetry (DSC) heating trace.

[0031] FIG.16 depicts the heat capacity change of neat polymers and exemplary polymer blends at Tg and Tg,blend (ΔCp) and polymer fragility (m). (a) ΔCp plotted as a function of PLiMTFSI weight fraction for exemplary PLiMTFSI – 7 / POEM (circles) blend electrolytes, exemplary PLiMTFSI – 16 / POEM (triangles) blend electrolytes, exemplary PLiMTFSI – 25 / POEM (diamonds) blend electrolytes, exemplary PLiMTFSI – 52 / POEM (squares) blend electrolytes, and exemplary PLiMTFSI – 105 / POEM (crosses) blend2101715-001234 -9- electrolytes. (b) m plotted as a function of PLiMTFSI weight fraction for exemplary PLiMTFSI – 7 / POEM (circles) blend electrolytes, exemplary PLiMTFSI – 16 / POEM (triangles) blend electrolytes, exemplary PLiMTFSI – 25 / POEM (diamonds) blend electrolytes, exemplary PLiMTFSI – 52 / POEM (squares) blend electrolytes, and exemplary PLiMTFSI – 105 / POEM (crosses) blend electrolytes. (c) Correlation between m and ΔCp. The solid line represents the fit of the data points. The error bars (most of which are smaller than the data points) represent the standard deviations from averaging the values obtained from a second and third DSC heating trace.

[0032] FIG.17 depicts DSC traces (third heating, exotherm up, 10 °C / min ramp rate, N2) for neat PLiMTFSI – 7 and exemplary PLiMTFSI – 7 / POEM blends, normalized by the total sample mass. Curves are shifted vertically for clarity.

[0033] FIG.18 depicts DSC traces (third heating, exotherm up, 10 °C / min ramp rate, N2) for neat PLiMTFSI – 16 and exemplary PLiMTFSI – 16 / POEM blends, normalized by the total sample mass. Curves are shifted vertically for clarity.

[0034] FIG.19 depicts DSC traces (third heating, exotherm up, 10 °C / min ramp rate, N2) for neat PLiMTFSI – 25 and exemplary PLiMTFSI – 25 / POEM blends, normalized by the total sample mass. Curves are shifted vertically for clarity.

[0035] FIG.20 depicts DSC traces on (third heating, exotherm up, 10 °C / min ramp rate, N2) for neat PLiMTFSI – 52 and exemplary PLiMTFSI – 52 / POEM blends, normalized by the total sample mass. Curves are shifted vertically for clarity.

[0036] FIG.21 depicts DSC traces on (third heating, exotherm up, 10 °C / min ramp rate, N2) for neat PLiMTFSI – 105 and exemplary PLiMTFSI – 105 / POEM blends, normalized by the total sample mass. Curves are shifted vertically for clarity.

[0037] FIG.22 depicts the current densities for an exemplary PLiMTFSI – 52 / POEM (r = 10:1) polymer blend. (a) The whole-time region of the current densities for the exemplary PLiMTFSI – 52 / POEM (r = 10:1) polymer blend electrolyte (thickness, L, = 0.05 cm) plotted as potential vs. time. (b) The 4000-6000 s region of the current densities for the exemplary PLiMTFSI – 52 / POEM (r = 10:1) polymer blend electrolyte (thickness, L, = 0.05 cm) plotted as potential vs. time. (c) Current density vs. potential for the exemplary PLiMTFSI – 52 / POEM (r = 10:1) blend electrolyte polymer blend.2101715-001234 -10-

[0038] FIG.23 depicts a thermal stability comparison between a PLiMTFSI – 52 / POEM (r = 10:1) polymer blend electrolyte and an exemplary PLiMTFSI – 52 / POEM (r = 10:1) / Fe2O3 nanorod composite electrolyte.

[0039] FIG.24 depicts a comparison of the overall conductivities between an exemplary PLiMTFSI – 52 (r = 10:1) / POEM polymer blend electrolyte and an exemplary PLiMTFSI – 52 / POEM (r = 10:1) / Fe2O3nanorod composite electrolyte. DETAILED DESCRIPTION

[0040] One aspect of the present disclosure is a composition that includes at least one or more of the following: (i) a glassy single-ion-conducting (SIC) polymer containing an anionic moiety chemically bound to the SIC polymer and a mobile cation; (ii) a flexible ion-conducting polymer blended with or chemically bound to the SIC polymer, wherein the flexible ion-conducting polymer contains at least one oxygen, fluorine, sulfur, nitrogen, or phosphorous-based moiety in a backbone and / or side chains; and / or (iii) optionally one or more nanoparticles dispersed in or chemically bound to at least one of the SIC polymers and / or the flexible ion-conducting polymers.

[0041] "Glassy polymers" and / or "glassy single-ion-conducting (SIC) polymer(s)" are polymers that have Tg’s greater than their use temperature. These polymers can provide improved structure integrity to the compositions, electrolytes, and / or devices disclosed herein.

[0042] "Flexible polymers" and / or "flexible ion-conducting polymer(s)" are polymers that have Tg’s lower than their use temperature.

[0043] As used herein, the term "about" refers to a value that is ± 10% of the stated value. In addition, it is understood that reference to a range of a first value to a second value includes the range of the stated values, e.g., a range of about 1 to about 5 also includes the more precise range of 1 to 5. It is also understood that the ranges disclosed herein include any selected subrange within the stated range, e.g., a subrange of about 50 to about 60 is contemplated in a disclosed range of about 1 to about 100.

[0044] Without being bound to or by any particular theory, the glassy polymer in the composition is believed to be intrinsically packing frustrated, thus leading to the generation of significant unstructured free volume with a percolating nature to serve as ion diffusion pathways. The strongly delocalized charge of the anion in the glassy polymer combined2101715-001234 -11- with the strong dipolar interaction between Li+and the heteroatoms (e.g., oxygen, fluorine, sulfur, nitrogen, phosphorous) of the flexible ion-conducting polymer facilitate the dissociation of Li+from its counterions, thereby generating a sufficient amount of free Li+that can directly contribute to high ionic conductivity. By tuning the molecular weight of the glassy polymer and the input Li+concentration, one skilled in the art can control the degree of packing frustration of the polymers and, correspondingly, the free volume within the compositions and / or electrolytes disclosed herein. The ionic conductivities achieved by the compositions and / or electrolytes disclosed herein are comparable to, and can exceed, the current best-in-class SPE [Li-bis(trifluoromethanesulfonyl)imide-doped poly(ethylene oxide)]. Moreover, the immobilized anion motion in the compositions and / or electrolytes disclosed herein can ensure that the lithium transference number will be close to unity. Thus, the concentration polarization within the devices disclosed herein can be reduced significantly, thereby enabling larger currents, higher charging rates, and improved overall battery safety.

[0045] Further without wishing to be bound to or by any particular theory, it is believed that the fully solid-state polymer compositions and / or electrolytes disclosed herein can leverage the intrinsic percolated free volume (i.e., free volume generated by packing frustration) of the polymers to achieve fast and efficient hopping-type ion transport, as in the case of inorganic electrolytes, that is completely decoupled from the polymers' segmental relaxation, while retaining good adhesion to the electrodes due to the elastic nature of the polymers. The immobilization of anions ensures that the ionic conductivity comes almost solely from the Li+motion, which is the contributing factor to actual electrical energy generation. Thus, the compositions and / or electrolytes disclosed herein can exhibit greatly improved ionic conductivity relative to most reported polymer electrolytes. Additionally, the high Li+transference number of the compositions and / or electrolytes disclosed herein could mitigate concentration polarization within a battery or a device disclosed herein, thereby leading to improved safety and efficiency with higher output capabilities. Moreover, the high electrochemical stability of the compositions and / or electrolytes disclosed herein could allow the use of energy-dense Li metal anodes in batteries. It is believed that the simple controlled synthesis and purification of the materials used in the compositions, devices, and / or electrolytes disclosed herein could enable facile commercial scaleup and widespread implementation into various devices, along with2101715-001234 -12- improved operational safety. Thus, the compositions, electrolytes, and / or devices disclosed herein are strong candidates for alternative liquid electrolytes and represent a significant advancement in the field of polymer electrolytes. In particular, the electrolytes disclosed herein, with their high ionic conductivities, Li+transference numbers, and electrochemical stabilities, are suitable for high-performing lithium-ion batteries.

[0046] In exemplary embodiments, the flexible ion-conducting polymer includes at least one polar group selected from -O-, =O, -F-, -CF3, -O-CF3, -S-, -SO2-, -N-, -P-, C=O, and C=N.

[0047] In exemplary embodiments, the composition includes one or more nanoparticles dispersed in the glassy SIC polymer and the flexible ion-conducting polymer.

[0048] In exemplary embodiments, the composition includes one or more nanoparticles chemically bound to the glassy SIC polymer.

[0049] In exemplary embodiments, the composition includes one or more nanoparticles chemically bound to the flexible ion-conducting polymer.

[0050] In exemplary embodiments, the composition includes one or more nanoparticles crosslinked with the flexible ion-conducting polymer.

[0051] In exemplary embodiments, the composition includes the glassy SIC polymer crosslinked with the flexible ion-conducting polymer.

[0052] In exemplary embodiments, the composition includes one or more block copolymers containing the flexible ion-conducting polymer and the glassy SIC polymer.

[0053] In exemplary embodiments, the composition includes one or more nanoparticles dispersed in one or more block copolymers containing the flexible ion- conducting polymer and the glassy SIC polymer.

[0054] In exemplary embodiments, the composition includes a hyperbranched core- shell structure containing a nanoparticle, wherein the nanoparticle forms the core, which can have a diameter of at most 100 nm, and is chemically bound to at least one polymer forming the shell of the hyperbranched core-shell structure. Those skilled in the art will appreciate that the core diameter can be modified or decreased to reduce the possibility of particle agglomeration while enhancing conductivity.

[0055] In exemplary embodiments, the mobile cation in the composition is selected from, but not limited to, an imidazolium, an aluminum ion, an iron ion, a lithium ion, a2101715-001234 -13- sodium ion, a potassium ion, a magnesium ion, a calcium ion, a nickel ion, a barium ion, a copper ion, a lead ion, a gold ion, a titanium ion.

[0056] In exemplary embodiments, the glassy SIC polymer has a structure containing a group of one or more of the following formulae: (Formula II),wherein: (i) each n and n' are independently a rational number selected from a range of 5 to 1000, 1 to 750, or 15 to 500; (ii) R is an ethylene methacrylate or ethylene acrylate of the following formula: (Formula III)1.5 or 2, a para- a );(iii) A- is selected from ),methane sulfonate ),2101715-001234 -14- (fluoromethanesulfonyl)),(trifluoromethanesulfonyl) )difluoromethane ),tris(1,1,1-trifluoromethoxy) ), tris(1,1,1,3,3,3-hexafluoropropan)(iv) B+is selected from ),1- ),1-ethylimidazolium ),2101715-001234 -15- Li+, K+, Na+, Mg2+, Ca2+, Zn2+, Ni2+, Cu2+, Ba2+, Pb2+, Fe2+, Al3+, or Ti3+.

[0057] In exemplary embodiments, the glassy SIC polymer has a structure containing a group of Formula (I) and / or Formula (II), wherein R is ethylene methacrylate, A- is (trifluoromethanesulfonyl)imide, B+is Li+, and n and n' are a rational number independently selected from 18 to 305.

[0058] When an amount, concentration, or other value or parameter is given as either a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range. It is not intended that the scope of the disclosure be limited to the specific values recited when defining a range.

[0059] In exemplary embodiments, the glassy SIC polymer has a molecular weight in a range of 6 kg / mol to 105 kg / mol.

[0060] In exemplary embodiments, the flexible ion-conducting polymer has a structure containing a group of one or more of the following formulae: (Formula V)Wherein: (i) each m and m' are independently a rational number selected from a range of 5 to 1000, 5 to 750, 10 to 500, or 10 to 250; and (ii) R’ is an oligo-oxyethylene methacrylate or an oligo-oxyethylene acrylate of the following formula:2101715-001234 -16-(Formula VI), wherein x is a rational number selected from a range of 2 to 20, 2,2,2-trifluoroethyl (meth) ),1H,1H,3H-tetrafluoropropyl (meth) ),2,2,3,3,3-pentafluoropropyl (meth) ),1H,1H,3H-hexafluorobutyl (meth) or2-(ethylthio)ethyl (meth) ).2101715-001234 -17-

[0061] In exemplary embodiments, the flexible ion-conducting polymer has a structure containing a group of Formula (IV) and / or Formula (V), wherein R' is an oligo- oxyethylene methacrylate of Formula (VI), wherein x is 9, and each m and m' are independently a rational number selected from a range of 12 to 210.

[0062] In exemplary embodiments, the flexible ion-conducting polymer has a molecular weight in a range of 6 kg / mol to 105 kg / mol.

[0063] In exemplary embodiments, the flexible ion-conducting polymer includes one or more of the following groups: (i) a poly(ethylene oxide) having a structure of Formula (VII): (Formula VII), (ii) aa structure of Formula (VIII): , (iii) a Formula (IX):(Formula IX),(X): (Formula X), (v) a poly a structure of Formula (XI):2101715-001234 -18- , (vi) a(XII): (Formula XII), and / ora structure of Formula (XIII): ,or 45 to 2270.

[0064] In exemplary embodiments, the composition includes one or more nanoparticles, wherein the one or more nanoparticles contain gold, a metal oxide, a metal carbide, a metal nitride, a metal boride, a metal dichalcogenide, boron nitride, graphene oxide, mesoporous silica, a conducting ceramic, or a combination thereof.

[0065] In exemplary embodiments, the composition includes one or more nanoparticles that contain a metal oxide selected from, but not limited to, lithium oxide (Li2O), aluminum oxide (Al2O3), iron oxide (Fe2O3), calcium oxide (CaO), magnesium oxide (MgO), zinc oxide (ZnO), barium oxide (BaO), potassium oxide (K2O), sodium oxide2101715-001234 -19- (Na2O), nickel oxide (NiO), copper oxide (CuO), lead oxide (PbO), gold oxide (Au2O3), titania (TiO2), and combinations thereof.

[0066] In exemplary embodiments, the composition includes one or more nanoparticles that contain a conducting ceramic selected from, but not limited to, lithium sulfide-phosphorus pentasulfide (Li2S-P2S5), lithium zinc phosphate [LiZr2(PO4)3], lithium lanthanum zirconate (Li7La3Zr2O12), and combinations thereof.

[0067] Another aspect of the present disclosure is a solid-state electrolyte including any one of the compositions disclosed herein.

[0068] In exemplary embodiments, the solid-state electrolyte includes a mobile cation selected from, but not limited to, an imidazolium, aluminum ion, iron ion, a lithium ion, sodium ion, potassium ion, magnesium ion, calcium ion, nickel ion, barium ion, copper ion, lead ion, gold ion, titanium ion, or a combination thereof.

[0069] In exemplary embodiments, the flexible ion-conducting polymer in the solid- state electrolyte includes ether oxygen-containing side chains, and the solid-state electrolyte has a molar concentration of ether oxygen units ([EO]) and lithium ions ([Li+]) ([EO]:[Li], or r) in a range of 5:1 < r < 30:1.

[0070] In exemplary embodiments, the glassy SIC polymer in the solid-state electrolyte has a number-average molecular weight (Mn) in a range of 6 to 105 kg / mol and contains a group having a structure of Formula (I) and / or Formula (II), wherein R is ethylene methacrylate, A- is (trifluoromethanesulfonyl)imide and B+is Li+.

[0071] In exemplary embodiments, the solid-state electrolyte has an ionic conductivity of at least 7×10−3S cm−1at 150 °C.

[0072] In exemplary embodiments, the solid-state electrolyte has a Li+transference number of at least 0.9.

[0073] In exemplary embodiments, the solid-state electrolyte has an electrochemical stability window of at least 4.7 V against Li+ / Li.

[0074] Another aspect of the present disclosure is a device including one or more of the following: an anode, a cathode, and / or any one of the solid-state electrolytes disclosed herein.

[0075] In exemplary embodiments, the device and / or the solid-state electrolyte included in the device includes one or more of the following: an imidazolium ionic liquid, an aluminum salt, an iron salt, a lithium salt, a sodium salt, a potassium salt, a magnesium2101715-001234 -20- salt, a calcium salt, a nickel salt, a barium salt, a copper salt, a lead salt, a gold salt, a titanium salt, or a combination thereof.

[0076] In exemplary embodiments, the device is a primary battery, a secondary battery, or a supercapacitor.

[0077] In exemplary embodiments, the device contains an alkali ion conductor composition and is an alkali-ion conducting solid-state rechargeable battery selected from, but not limited to, a lithium–ion battery, a lithium iron phosphate battery, a nickel–cadmium battery, a nickel–zinc battery, a nickel–metal hydride battery, a zinc–air battery, a lead–acid battery, or an alkaline battery.

[0078] In exemplary embodiments, the device includes a cathode that contains a material alkali metal-containing cathode materials and conversion-type cathode materials.

[0079] In exemplary embodiments, the device includes an anode that contains a material chosen from alkali metal-containing anode materials, silicon, graphite, and combinations thereof.

[0080] In exemplary embodiments, the device includes a cathode that contains a conversion type material selected from sulfur, sulfur composite materials, polysulfide materials, air, iodine, and / or metal sulfides; and / or includes an anode that contains a material selected from silicon-containing materials, tin and its alloys, tin / carbon, and / or phosphorus.

[0081] In exemplary embodiments, the device includes a liquid or gel electrolyte.

[0082] In exemplary embodiments, the composition, solid-state electrolyte, and / or device includes at least one nanofiller. The nanofiller can be selected from, but is not limited to, lithium oxide (Li2O), aluminum oxide (Al2O3), iron oxide (Fe2O3), calcium oxide (CaO), magnesium oxide (MgO), zinc oxide (ZnO), barium oxide (BaO), potassium oxide (K2O), sodium oxide (Na2O), nickel oxide (NiO), copper oxide (CuO), lead oxide (PbO), gold oxide (Au2O3), titania (TiO2), lithium sulfide-phosphorus pentasulfide (Li2S-P2S5), lithium zinc phosphate [LiZr2(PO4)3], lithium lanthanum zirconate (Li7La3Zr2O12), and combinations thereof.2101715-001234 -21- EXAMPLES

[0083] The present disclosure will be described in more detail with reference to the following Examples, which show exemplary embodiments in accordance with the present disclosure. The present disclosure is not limited to these exemplary embodiments.

[0084] EXAMPLE 1

[0085] CHEMICALS

[0086] Oligo-oxyethylene methyl ether methacrylate (OEM, > 99%, stabilized, average molar mass = 500 g / mol, Sigma-Aldrich, USA) was purified by passage through a basic aluminum oxide column. Lithium sulfonyl(trifluoromethane sulfonyl)imide methacrylate (LiMTFSI, 99%, stabilized, Specific Polymers, France), copper bromide [Cu(II)Br, 98%, Acros Organics, USA], tris(2-pyridylmethyl)amine (TPMA, 98%, Sigma- Aldrich, USA), ethyl 2-bromoisobutyrate (EBiB, 98%, Sigma-Aldrich, USA), tin(II) 2- ethylhexanoate [Sn(Oct)2, 92.5 – 100.0%, Sigma-Aldrich, USA], anisole (> 99%, Fisher Scientific, USA), dimethylformamide (DMF, Fisher Scientific, USA), diethyl ether (Fisher Scientific, USA), petroleum ether (Fisher Scientific, USA), acetone (Optima, Fisher Scientific, USA), acetone-d6 (with 0.03 v / v % tetramethylsilane, 99.9 atom% D, Thermo Scientific, USA), chloroform-d (with 0.02 – 0.04 v / v % tetramethylsilane, 99.8+ atom% D, Thermo Scientific, USA), and lithium bromide (LiBr, ≥ 99%, Sigma-Aldrich, USA) were used as received.

[0087] SYNTHESIS OF POLY(LITHIUM SULFONYL(TRIFLUOROMETHANE SULFONYL)IMIDE METHACRYLATE) (PLIMTFSI) AND POLY(OLIGO- OXYETHYLENE METHYL ETHER METHACRYLATE) (POEM)

[0088] PLiMTFSI and POEM homopolymers were synthesized by Activators ReGenerated by Electron Transfer Atom Transfer Radical Polymerization (ARGET ATRP) under similar protocols, as described in this example. In a typical PLiMTFSI polymerization, Cu(II)Br (0.0025 mmol), TPMA (0.025 mmol), and DMF were mixed and stirred for 2 h to ensure full complexation between the copper and the ligand. Then, the catalyst solution was combined with LiMTFSI (11.5 mmol), EBiB (0.025 mmol), and DMF in a three-neck, round-bottom Schlenk flask and was degassed via three freeze-pump-thaw cycles. Separately, Sn(Oct)2 (0.025 mmol) and anisole were mixed and sparged with argon gas under stirring for 30 min. To initiate the reaction, the reducing agent [Sn(Oct)2] solution was added to the reaction flask, which was placed in a thermostatic oil bath at 90 °C. The2101715-001234 -22- reaction conversion was monitored by Proton Nuclear Magnetic Resonance (1H NMR, Bruker AV600III) spectroscopy with acetone-d6(with 0.03 v / v % tetramethylsilane) as a solvent. The reaction was allowed to proceed for 17 h when the desired conversion (about 60%) was achieved. Then, the reaction was quenched by immersing the flask in liquid nitrogen, after which the flask was opened to air. Next, the reaction solution was precipitated into a mixture of petroleum ether and diethyl ether (1:1 by volume), and the polymer was separated from the supernatant via centrifugation. The polymer was redissolved in acetone and reprecipitated into petroleum ether / diethyl ether mixture until LiMTFSI monomer was not visible in the1H NMR spectrum of the purified polymer. At least four precipitations were required to sufficiently remove unreacted LiMTFSI. The polymer then was sealed in a drying chamber and dried under dynamic vacuum at ambient temperature until the Schlenk line baseline pressure was reached, which took about 10 h. To ensure that any residual solvent and moisture were removed, the temperature was slowly increased to 150 °C in 10 °C increments. After the Schlenk line baseline pressure was reached (about 4 h), the polymer was dried at 150 °C under dynamic vacuum for 48 h prior to storage in a -4 °C freezer in an argon-filled glovebox.

[0089] BLEND ELECTROLYTE FILM FABRICATION

[0090] PLiMTFSI and POEM stock solutions were prepared in an argon-filled glove box by dissolving each material separately in anhydrous DMF at about 10 wt% and then stirring each solution for 24 h. Next, the appropriate PLiMTFSI and POEM stock solutions were mixed at varying gravimetric ratios and stirred for another 48 h. The Li+concentration was quantified in all samples as [EO]:[Li] (denoted as r), which represents the molar ratio of ethylene oxide monomer segments in the side chains of POEM to Li+in PLiMTFSI. The composition of each blend electrolyte was denoted as ‘PLiMTFSI – X / POEM, r,’ in which X represents the PLiMTFSI number-average molecular weight Mn(Mn,PLiMTFSI) in kg / mol as determined by size exclusion chromatography.

[0091] Next, the blend electrolyte solution was taken out of the glovebox and drop- casted onto a Teflon o-ring mold to form a uniform film with 0.05 cm thickness (L) and 0.32 cm2area (A). The majority of the DMF was slowly evaporated under an inert atmosphere to ensure uniform thickness and prevent bubble formation in the film. After the film was formed, it was sealed in a drying chamber and dried under dynamic vacuum at ambient temperature until the Schlenk line baseline pressure was reached (about 20 h). To2101715-001234 -23- ensure residual solvent and moisture were removed, the temperature was slowly increased to 150 °C in 10 °C increments. After the Schlenk line baseline pressure was reached (about 6 h), the electrolytes were dried at 150 °C under dynamic vacuum for 48 h. The dried electrolyte films were stored in an argon-filled glovebox prior to characterization.

[0092] SIZE EXCLUSION CHROMATOGRAPHY (SEC)

[0093] SEC was performed on an HLC-8420 EcoSEC Elite Gel Permeation Chromatography instrument, with 0.1 vol% LiBr in DMF as the eluent at 25 °C (0.8 mL / min) and two PL aquagel-OH Mixed-H (8 μm, 50 ^7.5 mm) columns. A calibration curve was constructed using narrow-dispersity poly(methyl methacrylate) standards (885 – 2,210,000 g / mol, purchased from Agilent Technologies, USA). Samples were prepared by dissolving about 5 mg of polymer in about 5 mL of SEC solvent. All samples were left at ambient temperature for 24 h to ensure complete dissolution and then filtered using 0.1- ^m PTFE filters prior to measurement.

[0094] THERMOGRAVIMETRIC ANALYSIS (TGA)

[0095] Neat PLiMTFSI and neat POEM samples (2-3 mg) were loaded into 100- ^L platinum pans and heated under continuous N2 flow (50 mL / min). Measurements were conducted on a TA Instruments Discovery TGA instrument. Samples were heated at 20 °C / min to 115 °C, annealed at 115 °C for 5 min to remove any residual water, cooled at 20 °C / min to 50 °C, held at 50 °C for 1 min, and heated at 15 °C / min to 600 °C.

[0096] DIFFERENTIAL SCANNING CALORIMETRY (DSC)

[0097] Bulk electrolyte samples (about 8 mg) were hermetically sealed in 40-μL aluminum pans in an argon-filled glovebox. Measurements were conducted on a TA Instruments Discovery DSC instrument with an RCS90 cooling accessory. Baseline and cell constant calibrations were performed using sapphire disks and an indium standard, respectively. Three heating / cooling cycles at 10 °C / min ramp rate were performed under an N2environment within appropriate temperature windows: 0 to 200 °C for neat PLiMTFSI; - 80 to 150 °C for neat POEM, -80 to 120 °C for PLiMTFSI – 7 / POEM blends; -80 to 150 °C for PLiMTFSI – 16 / POEM blends; -80 to 160 °C for PLiMTFSI – 25 / POEM blends; - 80 to 190 °C for PLiMTFSI – 52 / POEM and PLiMTFSI – 105 / POEM blends. The reported Tgvalues were determined from the midpoints of the inflections in the third heating traces. The second and third heating traces were compared to ensure reproducibility upon heating.2101715-001234 -24-

[0098] DYNAMIC MECHANICAL ANALYSIS (DMA)

[0099] DMA was carried out using an ARES-G2 strain-control rheometer (TA Instruments). Samples were hot-pressed at 30 °C (for neat POEM), 170 °C (for neat PLiMTFSI – 52), and 60 °C (for PLiMTFSI – 52 / POEM, r = 10:1) for 5 min in the rheometer under an axial force of 0.2-1.0 N before shear measurements to improve contact between the polymer and the plates. For the neat POEM sample, a cone and plate geometry (with a 25-mm diameter and a 0.0998-rad cone angle) was used due to the liquid-like nature of the sample. For neat PLiMTFSI – 52 and PLiMTFSI – 52 / POEM, r = 10:1 samples, 8- mm-diameter parallel plates were used. An approximately 0.4-mm thick sample was placed between the cone and plate or between the two plates in a closed oven under an N2environment. The sample was exposed to ambient atmosphere for less than 1 min when loading into the rheometer, and thus, moisture uptake was minimized. Isothermal frequency sweeps were conducted at 5 °C temperature increments and at appropriate strain amplitudes, which were varied to keep sample behavior within the linear viscoelastic region (200 to 220% for neat POEM, 0.1 to 0.5% for neat PLiMTFSI – 52, and 0.5 to 0.8% for PLiMTFSI – 52 / POEM, r = 10:1). The temperature range was 30 to 150 °C, which is the same as the conductivity measurement temperature range and is of interest for practical battery operation.

[0100] ALTERNATING CURRENT (AC) IMPEDANCE SPECTROSCOPY

[0101] Ionic conductivities were measured using a Princeton Applied Research PARSTAT 2273 frequency response analyzer with a homemade test cell mounted on a Linkam HFS91 CAP stage, under vacuum in a standalone chamber. The homemade test cell consisted of two stainless steel electrodes and two aluminium blocking electrodes with a Teflon o-ring spacer in the middle to prevent short-circuiting. The blend electrolyte film was sandwiched between the aluminium electrodes, and the cell was assembled in an argon- filled glovebox. Prior to the ionic conductivity measurement, all samples were annealed at 60 °C for 3 h in the sealed test cell to ensure good contact with the aluminium electrodes, then the samples were cooled to 25 °C and held at that temperature for 1 h. The ionic conductivities were measured on heating between 30 °C and 150 °C in 10 °C increments. At each temperature, two impedance measurements were taken after annealing for 5 min and 8 min, respectively. The reported ionic conductivities at each temperature were the average of the ionic conductivities calculated for the two impedance measurements at that respective2101715-001234 -25- temperature. The differences between the two calculated ionic conductivities at a given temperature were generally on the order of 1% or less, which indicated that the cells were stable and that consistent ionic conductivity results were obtained during the process. The AC frequency range was 0.1 Hz to 1 MHz, and the voltage amplitude was 10 mV. The choice of a small voltage amplitude ensured a linear region of behavior to simplify the analysis. The bulk resistance (Rbulk) of the blend electrolyte was determined from the high- frequency plateau in the real impedance data, and the ionic conductivity (σ) was calculated using equation (1): ^^ ൌ^(equation 1).

[0102] AC impedancewas also conducted on three replicate lithium – lithium symmetrical cells with PLiMTFSI – 52 / POEM, r = 10:1 electrolyte to ensure consistent conductivity results were obtained between using blocking and non-blocking electrodes. The lithium foil (battery grade, 0.01 cm thickness, 7.1 cm width, lithium content ≥ 99.95%, China Energy Lithium Co., Ltd, China) was used as received. Lithium foil electrodes with 0.95 cm diameter (3 / 8 inch) were prepared using a hollow punch with a 3 / 8- inch (0.95 cm) cutting head (Mayhew Steel Products, Inc., USA) in an argon-filled glovebox.

[0103] POTENTIOSTATIC POLARIZATION

[0104] A lithium transference number (tLi+) was measured by potentiostatic polarization and AC impedance spectroscopy under vacuum using a Princeton Applied Research PARSTAT 2273 frequency response analyzer in a lithium – lithium symmetric cell that was mounted on a Linkam HFS91 CAP stage. The cell consisted of two stainless steel electrodes and two lithium electrodes with a Teflon o-ring spacer in the middle. The polymer blend electrolyte film (PLiMTFSI – 52 / POEM, r = 10:1) was sandwiched between the lithium electrodes, and the cell was assembled in an argon-filled glovebox. Three replicate lithium – lithium symmetric cells were made as described above. Prior to any electrochemical measurement, the cell was heated up to 60 °C and allowed to equilibrate for 3 h. Then, an AC impedance spectroscopy measurement was conducted prior to the potentiostatic polarization, and the initial impedance was recorded as a function of frequency. After this measurement, the cell was polarized with a potential of 10 mV (a small polarization voltage was chosen to avoid any significant electrochemical reactions that might affect the final results). For the first 0.98 s, a sampling rate of 1 ms-1was used to2101715-001234 -26- measure the initial current. This sufficiently fast sampling rate ensured accurate determination of the initial current. The current was closely monitored during the polarization process in 20-s time intervals, and the potential was applied for 6 h, at which point a steady-state current was reached. An AC impedance spectroscopy measurement then was performed again to extract the steady-state impedance, with an AC frequency range of 0.1 Hz – 1 MHz and a voltage amplitude of 10 mV. tLi+was determined using the Bruce- Vincent method (equation 2): ^^^^శ ൌூೄೄ^∆^ିூబோబ^. in which ISS and I0 are the∆V is the polarization voltage, and RSSand R0are the steady-state and initial interfacial impedance, respectively. The interfacial impedance was taken as the difference between the values of the minima at the bounds of the low-frequency semicircle in a Nyquist plot. The reported tLi+ value was taken as the average of the data obtained from the four cells.

[0105] CHRONOPOTENTIOMETRY

[0106] A limiting current density was determined through a chronopotentiometry method under vacuum using a Princeton Applied Research PARSTAT 2273 frequency response analyzer in a lithium – lithium symmetric cell that was mounted on a Linkam HFS91 CAP stage. The cell consisted of two stainless steel electrodes and two lithium electrodes with a Teflon o-ring spacer in the middle. The polymer blend electrolyte film (PLiMTFSI – 52 / POEM, r = 10:1) was sandwiched between the lithium electrodes, and the cell was assembled in an argon-filled glovebox. Three replicate lithium – lithium symmetric cells were made as described above. Prior to the measurement, the cell was heated up to 60 °C and allowed to equilibrate for 3 h. All experiments were performed at 60 °C under increasing current densities from 0.8 mA / cm2to 1.9 mA / cm2. The voltage was closely monitored during the measurements in 6-s time intervals. The limiting current density was determined to be the highest current density at which a steady-state potential was reached, which typically took 1.5 h.

[0107] LINEAR SWEEP VOLTAMMETRY

[0108] Electrochemical stability was determined by linear sweep voltammetry under vacuum using a Princeton Applied Research PARSTAT 2273 frequency response analyzer in a lithium – stainless steel cell that was mounted on a Linkam HFS91 CAP stage. The polymer blend electrolyte film (PLiMTFSI – 52 / POEM, r = 10:1) was sandwiched2101715-001234 -27- between the stainless steel electrode and the lithium electrode, with a Teflon o-ring in the middle of the two electrodes, then backed with another stainless steel electrode. The cell was assembled in an argon-filled glovebox. Three replicate lithium – stainless steel cells were made as described above. The experiment was performed at 60 °C under increasing cell potentials from 1.0 V to 6.0 V at a scan rate of 0.1 mV / s, and the current was closely monitored during the measurement.

[0109] EXPERIMENT 1 AND RESULTS:

[0110] To investigate the effect of the degree of packing frustration on the ion conduction behavior, POEM and a series of SIC homopolymers – PLiMTFSI – were synthesized via ARGET ATRP, Scheme 1:

[0111] (a) synthesis scheme for POEM, (b) synthesis scheme for PLiMTFSI. m and x represent the molar equivalents of the methacrylate monomers in the reaction schemes.

[0112] The molecular characterization of the exemplary POEM and PLiMTFSI used in this example are provided in Table 1. The NMR and SEC traces of these polymers are shown in FIG.1, FIG.2 and FIG.3.2101715-001234 -28- Table 1: SEC Characterization Data for the Exemplary POEM and PLiMTFSI Homopolymers Polymer Mna(kg / mol) Mwb(kg / mol) ĐcPOEM 5.9 7.5 1.27 PLiMTFSI – 7 7.0 9.1 1.29 PLiMTFSI – 16 16.3 18.1 1.11 PLiMTFSI – 25 25.6 32.5 1.27 PLiMTFSI – 52 52.4 68.6 1.31 PLiMTFSI – 105 105.7 141.6 1.34aNumber-average molecular weight as determined by SEC.bWeight-average molecular weight as determined by SEC.cDispersity as determined by SEC.

[0113] The Mnof the POEM was 5.9 kg / mol, and the Mnfor the PLiMTFSI (Mn,PLiMTFSI) ranged from 7.0 to 105.7 kg / mol. PLiMTFSI and POEM were blended at various ion concentrations at 5:1 < r < 30:1. PLiMTFSI and POEM were miscible in all the polymer blends, as indicated by a single Tgmeasured using DSC. The rigidity of PLiMTFSI and POEM was evaluated through DMA by measuring the shear storage modulus (see FIG.4), which can be used to describe the rigidity of a material, and PLiMTFSI has about 7 order-of-magnitude higher rigidity than POEM. In comparison to PEO / LiTFSI, the shear storage modulus of PLiMTFSI – 52 / POEM, r = 10:1 electrolyte has an at least about 2 order-of-magnitude enhancement (see FIG.5), owing to the PLiMTFSI incorporation.

[0114] The temperature-dependent ionic conductivities were determined by AC impedance spectroscopy using aluminium blocking electrodes, see FIG.6. The conductivity results obtained using lithium non-blocking electrodes with PLiMTFSI – 52 / POEM, r = 10:1 electrolyte (see FIG.7) are shown in Table 2. Table 2: Ionic Conductivity, ^, and Bulk Impedance, Rbulk, of a PLiMTFSI – 52 / POEM, r = 10:1 electrolyte in four cells at 60 °C (L = 0.05 cm, A = 0.32 cm2) ^ (S / cm) Rbulk (Ohms) aCell 11.10 ^-4 1420b10Cell 2 -51650b9.47 ^ 10Cell 39.-51690b25 ^ 10Cell 49.19 ^ 10-5 1700aCell 1 is made with aluminium blocking electrodes.bCells 2, 3, and 4 are made with lithium non-blocking electrodes.

[0115] The ionic conductivities obtained using blocking and non-blocking electrodes were in relatively good agreement. The data points were fit with either dashed or solid lines using the following delineations. The dashed lines were applied to conductivity2101715-001234 -29- results that were well described (R2≥ 0.99) by the Vogel–Tammann–Fulcher (VTF) equation (equation 3): ିாೌ^^ (equation 3), in which Ea is the pseudo with polymer segmental dynamics, R is the ideal gas constant, T is the absolute temperature in Kelvin, and T0 is the ideal Tg at which the free volume or configurational entropy becomes zero. In this experiment, T0was chosen to be 50 K below Tg of the blend electrolyte (Tg,blend), which is common for polyether-containing systems. The VTF-type behavior suggested that ion-polymer motion was cooperative, and that ion transport was closely coupled to the polymer segmental relaxation. The solid lines were applied to conductivity results that were well described (R2≥ 0.99) by the Arrhenius equation (equation 4): ^^ ൌ ^^^exp ^ିாೌோ்^ (equation 4), in which σ0is the ionichigh temperature, and Eais the pseudo activation energy associated with ion hopping. The Arrhenius-type behavior implied that ion transport was likely a thermally activated process as ions hopped from one available site to another. This type of ion transport was considered decoupled from polymer segmental relaxation.

[0116] At high ion concentrations (r = 5:1 and 10:1, FIG.6a and FIG.6b), all of the blends displayed Arrhenius-like ion diffusion (shown by solid lines) except PLiMTFSI – 7 / POEM, which exhibited VTF-like ion transport (shown by dashed lines). This prevalence of decoupled ion transport was likely a result of the free volume that comes from the packing frustration of both glassy PLiMTFSI, as well as transient TFSI- – Li+– EO crosslinks. This unstructured free volume can yield interconnected voids with various sizes and distributions as transport pathways, through which Li+can hop with enough thermal energy. Herein, the conductivities increased by about 2 orders of magnitude (from about 10-4S / cm to about 10-2S / cm at 150 °C) as Mn,PLiMTFSI increased from 16 kg / mol to 52 kg / mol. However, a drop in conductivities occurred when Mn,PLiMTFSI was raised to 105 kg / mol.

[0117] For blend electrolytes with low ion concentrations (r = 20:1 and 30:1, FIG. 6c and FIG.6d), the majority of blend systems displayed VTF-like ion diffusion behavior (shown by dashed lines), and only PLiMTFSI – 52 / POEM and PLiMTFSI – 105 / POEM systems exhibited Arrhenius-like ion transport (shown by solid lines). This crossover2101715-001234 -30- between VTF- and Arrhenius-type behavior at higher molecular weights likely occurred because longer chains impose more constraints on molecular movement due to chain connectivity, resulting in more frustrated chain packing. Additionally, the transient TFSI- – Li+– EO crosslinks were not as prevalent at the lower salt concentrations because there was sufficient coordination capacity available through the POEM. Taken together, these composition-dependent conductivity results suggest that variations in glassy polymer chain length and the ion concentration can be used to tune the degree of packing frustration and therefore the free volume within the materials.

[0118] This ion transport mechanism transition is illustrated in FIG.8 (FIG.8a and FIG.8b), wherein the conductivity is plotted as a function of Mn,PLiMTFSI. For electrolytes with high ion concentrations (r = 5:1 and 10:1), the conductivities initially improved with increasing Mn,PLiMTFSI (from 7 kg / mol to 52 kg / mol) then dropped when Mn,PLiMTFSI was further raised to 105 kg / mol. A slight deviation of this trend wasr = 5:1 at 60 °C (a drop in conductivities occurred as Mn,PLiMTFSI increased from 7 kg / mol to 16 kg / mol), which might be largely correlated with the local transport environment difference at 60 °C vs.90 °C due to the dynamic character of the free volume voids. For blend electrolytes with low ion concentrations (r = 20:1 and 30:1), the conductivities at lower molecular weights dropped with increasing Mn,PLiMTFSI (from 7 kg / mol to 25 kg / mol), likely due to an increase in Tg,blendacross the regime in which ion diffusion was dependent on polymer segmental relaxation. Then, the conductivities rose as Mn,PLiMTFSI increased to 52 kg / mol, likely because the ion transport mechanism transitioned from ion / polymer cooperative motion to ion hopping (demonstrated by the Arrhenius relationship in FIG.6c and FIG.6d), the latter of which is suggested to proceed faster than the former. Finally, the conductivities decreased when Mn,PLiMTFSI increased to 105 kg / mol. The nonmonotonic trend of conductivity vs. Mn,PLiMTFSIimplies that molecular weight is not the sole contributor to the polymer packing frustration. Apart from the molecular weight, there are other factors impacting the efficiency of polymer chain packing space and the corresponding free volume, such as the dispersity, the backbone rigidity, the ‘relative’ rigidity of the side group(s) vs. the backbone, the molecule symmetry, end-group chemistry, and inter- / intra- molecular interactions. These factors are typically cross-correlated in polymer systems.

[0119] The highest ionic conductivities were obtained in the blend system containing 52 kg / mol PLiMTFSI and 5.9 kg / mol POEM at r = 10:1, with overall2101715-001234 -31- conductivities comparable to both LiTFSI-doped POEM and PEO (FIG.8c). The tLi+ of this blend electrolyte was determined from potentiostatic polarization (using the current response before and after cell polarization) and AC impedance spectroscopy (using the impedance response). Table 3 depicts the impedance and current values extracted from AC impedance spectroscopy and potentiostatic polarization for the blend system containing 52 kg / mol PLiMTFSI and 5.9 kg / mol POEM at r = 10:1 in various cells (see FIG.9, FIG.10 FIG.11 and FIG.12). Table 3: Impedance and Current Values for a Blend System Containing 52 kg / mol PLiMTFSI and 5.9 kg / mol POEM at r = 10:1 Extracted from AC Impedance Spectroscopy and Potentiostatic Polarization Measurements of Four Lithium – Lithium Symmetric Cells R1R2R1*R2* bR0cRSSdI0ISStLi+(Ohms) (Ohms) (Ohms) (Ohms) (Ohms) (Ohms) (A) (A) aCell1690 1750 2720 2820 60 1001.10 ^10-79.90 ^10-8 0.90aACell B1630 1720 2510 2670 90 160 1.13 ^10-7 9.97 ^10-8 0.88aCell1570 1680 274 -7 -8C0 2810 110 70 1.13 ^10 9.89 ^10 0.87aCell1640 1740 2710 2850 100 14 -7 -8D0 1.11 ^10 9.76 ^10 0.88

[0120] A value close to unity (tLi+ about 0.9) was obtained for all cells due to the immobilized anion. The Li+conductivities were calculated by multiplying the overall conductivities by tLi+. As shown in FIG.8d, the Li+conductivities of PLiMTFSI – 52 / POEM were significantly higher than the LiTFSI-doped POEM and PEO systems across a broad temperature range. Thus, PLiMTFSI – 52 / POEM simultaneously imparted both high ionic conductivities and high Li+selectivities, which suggests that the polymer packing frustration is a powerful tool for developing all-solid-state SIC SPEs with improved performance.

[0121] To quantify the ion transport efficiency, the angular-frequency-dependent conductivity data (from both the 5-min and 8-min impedance measurements) were fit by the Jonscher Power Law to estimate ion hopping times. These ion hopping times are displayed in FIG.13 (see FIG.13a). The Jonscher Power Law equation describes the relaxation phenomena of the ionic environment arising from the hopping of mobile charge carriers (equation 5): σAC= σ0+ Aωn(equation 5),2101715-001234 -32- in which σAC is the AC conductivity, σ0 is the direct current conductivity, A is the strength of polarizability, ω is the angular frequency of the sinusoidal voltage applied to the cell, and n is the dimensionless frequency exponent representing the interaction between mobile ions and surrounding lattice. For blend electrolytes displaying Arrhenius-like conductivities, the ion hopping time (τ) can be calculated from equation 6: ^^ ൌଶగ^^బభ (equation 6), ಲ ^^ in which τ has an inverse relationship with the conductivity, as higher conductivities correspond to shorter ion hopping times (FIG.13b and FIG.13c). The results for 60 °C, 90 °C, and 110 °C (see FIG.14) are located in Table 4. Table 4: Ion Hopping Time Results for Exemplary PLiMTFSI / POEM Blends Exhibiting Arrhenius-like Ion Transport Polymer blend [EO]:[Li] τa(s) 60 ° ^^ 90 ° ^^ 110 ° ^^ PLiMTFSI – 16 5:1 1.7×10-32.0×10-44.2×10-5 / POEM 10:1 2.9×10-44.3×10-51.4×10-5PLiMTFSI – 25 5:1 6.0×10-41.1×10-45.6×10-5 / POEM 10:1 3.2×10-51.1×10-56.4×10-6PLiMTFSI – 52 5:1 5.7×10-61.0×10-65.0×10-7 / POEM 10:1 3.4×10-65.0×10-72.3×10-720:1 7.2×10-61.3×10-67.1×10-730:1 2.1×10-54.3×10-61.9×10-6PLiMTFSI – 5:1 2.5×10-41.9×10-46.5×10-5105 / POEM 10:1 5.3×10-54.0×10-51.7×10-520:1 1.0×10-48.3×10-54.1×10-530:1 8.9×10-44.0×10-43.0×10-4aIon hopping time as determined from fitting the angular-frequency-dependent conductivities (from both 5-min and 8-min impedance measurements) by the Jonscher Power Law.

[0122] As Mn,PLiMTFSIincreased from 16 kg / mol to 52 kg / mol, the conductivities of the blend electrolytes at 60 °C were enhanced by about 2 orders of magnitude for r = 5:1 (from about 10-6S / cm to about 10-4S / cm) and about a 1 order of magnitude for r = 10:1 (from about 10-5S / cm to about 10-4S / cm), while τ had about a 2 order-of-magnitude decrease for r = 5:1 (from about 10-3s to about 10-5s) and about a 1 order-of-magnitude drop for r = 10:1 (from about 10-4s to about 10-5s) (FIG.13b). As Mn,PLiMTFSI was increased further from 52 kg / mol to 105 kg / mol, the conductivities dropped, and correspondingly, an upturn in τ was found (FIG.13b and FIG.13c). The improved conductivities at intermediate2101715-001234 -33- Mn,PLiMTFSI could be attributed to increased packing frustration and more available sites with decreased distance between them; therefore, ions could more easily hop from one site to another, resulting in reduced τ.

[0123] EXPERIMENT 2 AND RESULTS

[0124] To quantify the effect of the exemplary blend electrolyte composition on the degree of packing frustration, the thermal behaviors of the neat PLiMTFSI and blend electrolytes were examined using DSC. As shown in FIG.15 (see FIG.15a and FIG.15b), the Tgof neat PLiMTFSI (Tg,PLiMTFSI) followed the Flory – Fox equation (equation 7): T = T −^(equation 7), in whichan empirical parameter that is related to the free volume generated by polymer chain ends. Using equation 7, the Tg,∞,PLiMTFSIwas calculated to be 409 K (136 °C) – close to the Tgs of PLiMTFSI – 52 (132 °C) and PLiMTFSI – 105 (134 °C), thus suggesting that chain-end effects become almost negligible at the higher molecular weights (see the plateau in FIG.15b).

[0125] As shown in FIG.15c, the heat capacity change of PLiMTFSI at Tg,PLiMTFSI (ΔCp,PLiMTFSI) is inversely related to Mn,PLiMTFSI. ΔCp,PLiMTFSIrepresents the configurational variations (freedom) of the polymer at Tg,PLiMTFSI, and initially decreased sharply with Mn,PLiMTFSIfrom 7 kg / mol to 25 kg / mol, then began to plateau as Mn,PLiMTFSIexceeded 25 kg / mol (e.g., in the 52 and 105 kg / mol specimens). The Mn,PLiMTFSI at which ΔCp,PLiMTFSI becomes invariant is comparable to the value associated with Tg,∞,PLiMTFSI. As the chains-end concentration decreases, less configurational freedom is conferred to the polymer. Moreover, for 7, 16, 25, and 52 kg / mol specimens, ΔCp,PLiMTFSI and Tg,PLiMTFSI followed Boyer’s rule (equation 8 and FIG.15d): ΔCp,PLiMTFSI × Tg,PLiMTFSI = constant (equation 8).

[0126] A slight deviation from this simple relationship was seen in the 105 kg / mol specimen. This deviation has been reported for cases in which high-Mn rigid polymers are associated with higher vibrational contributions to ΔCp. The quantitatively similar behavior between Mn,PLiMTFSI-dependent Tg,PLiMTFSI and ΔCp,PLiMTFSI indicates that Mn, Tg, ΔCp, free volume, and configurational freedom are all closely correlated with each other.

[0127] For the blend electrolytes, Tg,blend (FIG.15e) could be fit to the Gordon – Taylor equation (equation 9):2101715-001234 -34- ^^ ,in which w1and w2are the weight component, POEM and PLiMTFSI, respectively, and Tg,1 and Tg,2 are the Tg values of neat POEM and PLiMTFSI, respectively. The Gordon – Taylor equation describes the impact of composition and deviations from ideal mixing on polymer blend Tgs, in which the adjustable fitting parameter k typically ranges between 0 and 1 and accounts for negative deviations from the ideal binary mixing. As shown in FIG.15f, k initially increased sharply with Mn,PLiMTFSIfrom 7 kg / mol to 25 kg / mol, then plateaued as Mn,PLiMTFSI exceeded 25 kg / mol (e.g., in the 52 and 105 kg / mol specimens). This trend quantitatively mirrors the Tg,PLiMTFSIand ΔCp,PLiMTFSI behaviors as a function of molecular weight. k can be correlated with ΔCp and / or free volume (re)distribution upon mixing, depending on whether equation 9 is derived from the configurational entropy theory or the free volume theory. k is also related to conformational energy barriers, contact between polymer components, and chain conformational (re)arrangement. The Mn-dependence of k is in line with the literature, in which k increases are especially evident for the blends with lower-Mn(≤ 40 kg / mol) rigid components, and k is nearly constant for blends with higher Mn (> 40 kg / mol) rigid polymers. In the 7, 16, and 25 kg / mol PLiMTFSI-containing specimens, the rapid change in k was attributed to stronger intermolecular interactions within the blend electrolyte, specifically the electrostatic repulsions between PLiMTFSI pendent groups and the steric repulsions between methyl groups (in both PLiMTFSI and POEM). When higher molecular-weight PLiMTFSI (52 and 105 kg / mol) was incorporated into the blend electrolytes, k nearly plateaued, likely due to the decreased chain-end effect illustrated by the Tg,PLiMTFSIand ΔCp,PLiMTFSIbehaviors.

[0128] EXPERIMENT 3 AND RESULTS

[0129] To investigate blend electrolyte composition effects on the thermodynamic and kinetic fragility, DSC was used to determine both fragility values. The thermodynamic fragility was expressed as ΔCp. As shown in FIG.16 (see FIG.16a), ΔCpdecreased as the PLiMTFSI weight fraction increased, and this drop in ∆Cp could suggest stronger restrictions on molecular rearrangements within the electrolytes due to strengthened electrostatic repulsions (between PLiMTFSI pendent groups). The kinetic fragility m can be estimated from a straightforward relationship between m and Tg (equation 10) using the Williams–Landel–Ferry equation with C1(17.4) and C2(51.6 K):2101715-001234 -35- m =^భ^ ^ Tg ≈ 0.34Tg మ (equation 10), wherein m is a measure of the packing frustration, in which larger values of m indicate that the system is more packing frustrated. As shown in FIG.16b, the kinetic fragility increased upon incorporating higher weight fractions of PLiMTFSI into the blend electrolyte, likely because the repulsive interactions between PLiMTFSI pendent groups become stronger, disfavoring efficient chain packing.

[0130] The thermodynamic fragility, packing frustration, and Tg of the exemplary polymers (see FIG.17, FIG.18, FIG.19, FIG.20, and FIG.21) used in this example are provided in Table 5. Table 5: ΔCp, Tg, and m for Neat POEM, Neat PLiMTFSI, and Exemplary PLiMTFSI / POEM Blends2101715-001234 -36- Polymer / polymerabTbcblend[EO]:[Li]ΔCp gbd(kJ / kg ^K)( ° ^^)mPOEM N / A 0.701 ± 0.003 -65.0 ± 0.5 70.8 ± 0.2 PLiMTFSI – 7 N / A 0.257 ± 0.002 64.9 ± 1.0 114.9 ± 0.3 PLiMTFSI – 16 0.240 ± 0.003 95.1 ± 2.0 125.2 ± 0.7 PLiMTFSI – 25 0.229 ± 0.001 111.2 ± 0.6 130.7 ± 0.2 PLiMTFSI – 52 0.222 ± 0.005 132.0 ± 0.6 137.7 ± 0.2 PLiMTFSI – 105 0.213 ± 0.004 134.0 ± 2.7 138.4 ± 0.9 PLiMTFSI – 7 / 5:1 0.458 ± 0.001 -23.2 ± 0.2 85.0 ± 0.1 POEM 10:1 0.516 ± 0.005 -40.2 ± 0.4 79.2 ± 0.1 20:1 0.557 ± 0.006 -50.0 ± 0.1 75.9 ± 0.1 30:1 0.583 ± 0.005 -54.0 ± 0.2 74.5 ± 0.1 PLiMTFSI – 16 / 5:1 0.455 ± 0.007 -7.0 ± 0.4 90.5 ± 0.1 POEM 10:1 0.510 ± 0.008 -27.9 ± 0.3 83.4 ± 0.1 20:1 0.593 ± 0.009 -45.2 ± 0.5 77.5 ± 0.2 30:1 0.622 ± 0.001 -50.5 ± 0.2 75.7 ± 0.1 PLiMTFSI – 25 / 5:1 0.447 ± 0.003 6.4 ± 0.3 95.0 ± 0.1 POEM 10:1 0.500± 0.004 -19.8 ± 0.2 86.1 ± 0.1 20:1 0.579 ± 0.005 -38.3 ± 0.7 80.0 ± 0.2 30:1 0.611 ± 0.004 -46.1 ± 0.4 77.5 ± 0.1 PLiMTFSI – 52 / 5:1 0.398 ± 0.001 18.1 ± 0.3 99.4 ± 0.1 POEM 10:1 0.495 ± 0.003 -12.0 ± 0.2 88.9 ± 0.1 20:1 0.594 ± 0.006 -33.4 ± 0.2 81.3 ± 0.1 30:1 0.633 ± 0.005 -43.7 ± 0.4 78.2 ± 0.1 PLiMTFSI – 105 5:1 0.365 ± 0.015 22.0 ± 0.3 103.0 ± 0.1 / POEM 10:1 0.465 ± 0.002 -8.9 ± 0.2 92.1 ± 0.1 20:1 0.500 ± 0.003 -31.3 ± 0.3 83.0 ± 0.1 30:1 0.571 ± 0.007 -41.0 ± 0.8 80.0 ± 0.3aHeat capacity change at Tg as determined from the third DSC heating trace.bStandard deviation as determined from averaging the second and third DSC heating traces.cTgas determined from the third DSC heating trace.dKinetic fragility as determined from the Tg value from the third DSC heating trace.

[0131] The correlation between the thermodynamic and kinetic fragility of the exemplary blend electrolytes is shown in FIG.16c. The connection between the two fragility parameters enables the prediction of m. For rigid polymers, m is strongly dependent on Mn and ranges from about 80 to about 200 as Mn increases, whereas for flexible polymers, m is only weakly dependent on Mn and typically ranges from about 40 to about 80 as Mn increases. Higher values of m suggest that ion transport is largely decoupled from the matrix segmental relaxation (Arrhenius-like ion hopping motion). This trend is in line with the ion transport transitions from VTF-like to Arrhenius-like (FIG.6). However, it is difficult to find a generalized ‘cutoff’ value to distinguish VTF-like vs. Arrhenius-like ion2101715-001234 -37- transport. For instance, PLiMTFSI – 7 / POEM (r = 5:1) had a m of about 114 with VTF- like ion transport, while PLiMTFSI – 16 / POEM (r = 5:1) had a m of about 90 but with Arrhenius-like ion hopping. As mentioned previously, polymer molecular characteristics, architecture, chemistry, backbone / side group rigidity, and molecular interactions all contribute to the packing efficiency within polymer materials.

[0132] EXPERIMENT 4 AND RESULTS

[0133] The limiting current density of the exemplary PLiMTFSI – 52 / POEM, r = 10:1 blend electrolyte was measured through a chronopotentiometry method on a lithium – lithium symmetric cell under increasing current densities from 0.8 mA / cm2to 1.9 mA / cm2. The potential vs. time data are shown in FIG.22 (see FIG.22a and FIG.22b). Three replicate cells were produced, and the potential responses were in good agreement across all cells. The measurement temperature for the limiting current density was chosen to be 60 ^C to compare with literature data at similar temperatures to minimize any potential temperature impacts on the comparative results. The limiting current density of PLiMTFSI – 52 / POEM, r = 10:1 was 1.8 mA / cm2, i.e., the highest current density at which a steady- state potential was reached. The limiting current density of the exemplary SIC polymer blend electrolyte (1.8 mA / cm2, electrolyte thickness, L, = 0.05 cm) was comparable to the theoretical limiting current density of PEO / LiTFSI (about 1.8 mA / cm2, electrolyte thickness = 0.025 cm) at the same ion concentration and surpassed that of a number of solvent- plasticized SIC polymers. Although the effect of the electrolyte thickness on the limiting current density has been well-established for dual-ion-conducting polymers, such a study is not commonly undertaken for SIC systems. Theoretically, limiting current densities in SIC polymers should be close to infinity as tLi+approaches 1 if one can neglect chain mobility (and thereby no anion mobility). Herein, in comparison to solvent-plasticized SIC systems, the enhanced limiting current densitybe attributed to the high-MnPLiMTFSI with bulky side groups and transient TFSI- – Li+– EO crosslinks at high ion concentrations (r = 10:1). Both features significantly reduce the ion mobility in this solid-state, SIC, polymer- blend electrolyte.

[0134] The electrochemical stability of the exemplary blend electrolyte was determined by linear sweep voltammetry on a lithium – stainless steel cell (see FIG.22c). Three replicate cells were produced, and the current density responses were in good agreement among all the cells. In PLiMTFSI – 52 / POEM, r = 10:1 electrolyte, the current2101715-001234 -38- densities were below 0.01 mA / cm2in the 1.0 to 4.7 V voltage window, then increased rapidly above 4.7 V, likely due to oxidation. This electrochemical stability was significantly enhanced in comparison to the benchmark PEO / LiTFSI (about 3.5 V against Li+ / Li). Overall, these results demonstrate that restricting anion motion is an effective approach to realize improved performance in full SPEs.

[0135] CONCLUSIONS DRAWN FROM RESULTS OF EXAMPLE 1

[0136] The results of the experiments of Example 1 demonstrate that a fully solid- state, single-ion-conducting, polymer-blend electrolyte with improved ion transport can be achieved by overcoming the constraints of polymer segmental relaxation. The rigid PLiMTFSI with high Mn(52 kg / mol) led to significant chain packing frustration within the electrolyte at relatively high ion concentrations (e.g., [EO]:[Li] = 10:1) and generated percolating free volume that served as interconnected Li+diffusion pathways. As the blend electrolyte became more packing frustrated with increasing Mn,PLiMTFSI and ion concentration, the ion transport transitioned from being closely coupled to polymer segmental dynamics (VTF-like) to rapid and selective hopping (Arrhenius-like) across a broad temperature range (30 to 150 °C), well above Tg,blend. For example, the blend containing 52 kg / mol PLiMTFSI and 5.9 kg / mol POEM at r = 10:1 exhibited superior ionic conductivities (about 7 ൈ 10-3S / cm at 150 °C), Li+selectivities (tLi+= 0.9), electrochemical stabilities up to 4.7 V against Li+ / Li, and limiting current densities of 1.8 mA / cm2(electrolyte thickness = 0.05 cm).

[0137] These results suggest that SIC polymer blend electrolytes and compositions disclosed herein can be a promising alternative to the benchmark PEO / LiTFSI system. Additionally, the polymer packing efficiency and corresponding thermal and conductive properties in these blends / compositions could be easily tuned by polymer molecular characteristics, such as molecular weight, and a correlation between thermodynamic and kinetic fragility was empirically determined to assist in assessing the temperature-dependent conduction behavior. Taken together, the SIC polymer blend electrolytes / compositions disclosed herein are capable of overcoming the trade-off between high tLi+ and high ionic conductivity, highlighting the potential of decoupling ion transport from segmental relaxation to generate SPEs with improved safety, energy efficiency, and output characteristics.

[0138] EXAMPLE 2:2101715-001234 -39-

[0139] PLiMTFSI – 52 / POEM – Fe2O3 Composite Electrolyte

[0140] CHEMICALS

[0141] PLiMTFSI – 52 and POEM were taken from EXAMPLE 1. Fe2O3 nanorod water dispersion (20 wt%, 10 nm × 50 nm) was purchased from CD Bioparticles, USA.

[0142] POLYMER COMPOSITE ELECTROLYTE FILM FABRICATION

[0143] PLiMTFSI – 52 and POEM were weighed in an argon-filled glovebox. The materials then were taken outside the glovebox to dissolve separately in water at about 10 wt% and then stirred for 24 h. Next, the appropriate PLiMTFSI and POEM stock solutions were mixed with Fe2O3nanorod water dispersion at desired gravimetric ratios and stirred for another 48 h to have a composition of r = 10 and Fe2O3 wt% = 1 wt%.

[0144] Next, the composite electrolyte solution was drop-casted onto a Teflon o- ring mold to form a uniform film with 0.05 cm thickness (L) and 0.32 cm2area (A). The majority of the water was slowly evaporated under an inert atmosphere to ensure uniform thickness and prevent bubble formation in the film. After the film was formed, it was sealed in a drying chamber and dried under dynamic vacuum at ambient temperature until the Schlenk line baseline pressure was reached (about 15 h). To ensure that any residual water was removed, the temperature was slowly increased to 120 °C in 10 °C increments. After the Schlenk line baseline pressure was reached (about 5 h), the electrolytes were dried at 120 °C under dynamic vacuum for 48 h. The dried electrolyte films were stored in an argon-filled glovebox prior to characterization.

[0145] THERMOGRAVIMETRIC ANALYSIS (TGA)

[0146] PLiMTFSI – 52 / POEM – Fe2O3sample (3 mg) was loaded into 100- ^L platinum pans and heated under continuous N2 flow (50 mL / min). Measurements were conducted on a TA Instruments Discovery TGA instrument. The sample was heated at 20 °C / min to 115 °C, annealed at 115 °C for 5 min to remove any residual water, cooled at 20 °C / min to 50 °C, held at 50 °C for 1 min, and heated at 15 °C / min to 600 °C.

[0147] ALTERNATING CURRENT (AC) IMPEDANCE SPECTROSCOPY2101715-001234 -40-

[0148] Ionic conductivities were measured using a Princeton Applied Research PARSTAT 2273 frequency response analyzer with a homemade test cell mounted on a Linkam HFS91 CAP stage, under vacuum in a standalone chamber. The homemade test cell consisted of two stainless steel electrodes and two aluminium blocking electrodes with a Teflon o-ring spacer in the middle to prevent short-circuiting. The composite electrolyte film was sandwiched between the aluminium electrodes, and the cell was assembled in an argon-filled glovebox. Prior to the ionic conductivity measurement, the sample was annealed at 60 °C for 3 h in the sealed test cell to ensure good contact with the aluminium electrodes, then the sample was cooled to 25 °C and held at that temperature for 1 h. The ionic conductivities were measured on heating between 30 °C and 150 °C in 10 °C increments. At each temperature, two impedance measurements were taken after annealing for 5 min and 8 min, respectively. The reported ionic conductivities at each temperature were the average of the ionic conductivities calculated for the two impedance measurements at that respective temperature. The differences between the two calculated ionic conductivities at a given temperature were generally on the order of 1% or less, which indicated that the cells were stable and that consistent ionic conductivity results were obtained during the process. The AC frequency range was 0.1 Hz to 1 MHz, and the voltage amplitude was 10 mV. The choice of a small voltage amplitude ensured a linear region of behavior to simplify the analysis. The bulk resistance (Rbulk) of the composite electrolyte was determined from the high-frequency plateau in the real impedance data, and the ionic conductivity (σ) was calculated using equation (1).

[0149] EXPERIMENT 1 AND RESULTS:

[0150] To investigate the impact of the Fe2O3incorporation on the thermal stability of the composite electrolyte, the thermal degradation behavior of the polymer blend (PLiMTFSI – 52 / POEM) and the polymer-nanorod composite (PLiMTFSI – 52 / POEM – Fe2O3) electrolytes were studied using TGA (see FIG.23). The composite electrolyte exhibited a lower temperature at 5% mass loss (T5%) in comparison to PLiMTFSI – 52 / POEM, indicating a decrease in thermal stability upon the addition of the Fe2O3.

[0151] EXPERIMENT 2 AND RESULTS:

[0152] The temperature-dependent ionic conductivities were determined by AC impedance spectroscopy using aluminium blocking electrodes (see FIG.24). The conductivities of the composite electrolyte were well described (R2≥ 0.99) by the Arrhenius2101715-001234 -41- equation (equation 4) and exceeded the polymer blend electrolyte (PLiMTFSI – 52 / POEM) across a wide temperature range (30 to 150 °C) under the same ion concentration. This conductivity enhancement is likely due to the creation of additional percolating pathways for ion conduction. The high aspect ratio of the Fe2O3nanorod (length / diameter = 5) facilitates a lower percolation threshold and increases the likelihood of forming continuous conductive networks within the material, and therefore enhanced overall ion conduction efficiency.

[0153] CONCLUSIONS DRAWN FROM RESULTS OF EXAMPLE 2

[0154] The results of the experiments of Example 2 demonstrate that a fully solid- state, polymer-nanorod composite electrolyte with further improved ion transport can be achieved by introducing additional diffusion pathways with a low percolation threshold, resulting in superior ionic conductivities (about 8 ൈ 10-3S / cm 150 °C) and about 2-time conductivity enhancement at 30 °C in comparison to an exemplary polymer blend electrolyte (PLiMTFSI – 52 / POEM) at the same ion concentration (r = 10:1).

[0155] It will be appreciated by those skilled in the art that the present disclosure can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted. The scope of the disclosure is indicated by the appended claims rather than the foregoing description and all changes that come within the meaning and range and equivalence thereof are intended to be embraced therein.

Claims

2101715-001234 -42- CLAIMS:

1. A composition comprising: a glassy single-ion-conducting (SIC) polymer comprising an anionic moiety chemically bound to a backbone or side chains of the glassy SIC polymer and a mobile cation; a flexible ion-conducting polymer blended with or chemically bound to the SIC polymer, wherein the flexible ion-conducting polymer comprises an oxygen-, a fluorine-, a sulfur-, a nitrogen, or a phosphorous-containing moiety in a backbone or side chains of the flexible ion-conducting polymer; and optionally one or more nanoparticles dispersed in or chemically bound to at least one of the SIC polymer and ion-conducting polymer.

2. The composition according to claim 1, wherein the composition comprises one of the following: the optional one or more nanoparticles dispersed in the glassy SIC polymer and the flexible ion-conducting polymer; the flexible ion-conducting polymer blended with the glassy SIC polymer, wherein the glassy SIC polymer is chemically bound to one or more nanoparticles; the glassy SIC polymer blended with the flexible ion-conducting polymer, wherein the flexible ion-conducting polymer is chemically bound to one or more nanoparticles; the glassy SIC polymer blended with the flexible ion-conducting polymer, wherein the flexible ion-conducting polymer is crosslinked with one or more nanoparticles; one or more nanoparticles dispersed in the glassy SIC polymer, wherein the glassy SIC polymer is crosslinked with the flexible ion-conducting polymer; a block copolymer consisting of the flexible ion-conducting polymer and the glassy SIC polymer; one or more nanoparticles dispersed in a block copolymer consisting of the flexible ion-conducting polymer and the glassy SIC polymer; or2101715-001234 -43- a hyperbranched core-shell structure containing a nanoparticle, wherein the nanoparticle forms a core of the hyperbranched core-shell structure and is chemically bound to at least one polymer that forms a shell of the hyperbranched core-shell structure.

3. The composition according to claim 1, wherein the glassy SIC polymer has a structure containing a group of one or more of the following formulae: (Formula II),wherein: (i) each n and n' are independently a rational number selected from a range of 5 to 1000, 1 to 750, or 15 to 500; (ii) R is either an ethylene methacrylate or an ethylene acrylate of the following formula: (Formula III)from 0.5, 1.0, 1.5, or 2, a para- a carbonyl ( );2101715-001234 -44- (iii) A- is selected from ),methane sulfonate),(fluoromethanesulfonyl) ),(trifluoromethanesulfonyl) )difluoromethane ),tris(1,1,1-trifluoromethoxy) ), tris(1,1,1,3,3,3-hexafluoropropan)2101715-001234 -45- triethoxy(iv) B+is selected from imidazolium ),1- ),1- ), Li+, K+, Na+,Ba2+, Pb2+, Fe2+, Al3+, or Ti3+4. The composition according to claim 3, wherein R is ethylene methacrylate, A- is (trifluoromethanesulfonyl)imide, B+is Li+, and n and n' are independently a rational number selected from a range of 18 to 305; and wherein the glassy SIC polymer has a molecular weight in a range of 6 kg / mol to 105 kg / mol.

5. The composition according to claim 1, wherein the flexible ion-conducting polymer has a structure containing a group of one or more of the following formulae: (Formula V)(i) each m and m' are independently a rational number selected from a range of 5 to 1000, 5 to 750, 10 to 500, or 10 to 250; and2101715-001234 -46- (ii) R' is either an oligo-oxyethylene methacrylate or either an oligo- oxyethylene acrylate of the following formula:(Formula VI), wherein x is a rational number selected from a range of 2 to 20, 2,2,2-trifluoroethyl (meth) ),1H,1H,3H-tetrafluoropropyl (meth) ),2,2,3,3,3-pentafluoropropyl (meth) ),1H,1H,3H-hexafluorobutyl (meth) or2101715-001234 -47- 2-(ethylthio)ethyl (meth)).

6. The composition according to claim 5, wherein the flexible ion-conducting polymer has a structure containing a group of Formula (IV) and / or Formula (V), wherein R' is an oligo-oxyethylene methacrylate of Formula (VI), wherein x = 9, m and m' are independently a rational number selected from a range of 12 to 210; and wherein the flexible ion-conducting polymer has a molecular weight in a range of 6 kg / mol to 105 kg / mol.

7. The composition according to claim 1, wherein the flexible ion-conducting polymer comprises one or more of: (i) a poly(ethylene oxide) having a structure of Formula (VII): (Formula VII),(ii) a poly a of Formula (VIII): (Formula VIII), (iii) a polyof Formula (IX):2101715-001234 -48-(Formula IX), (iv) a poly(vinyl alcohol) having a structure of Formula (X): (Formula X),(v) a poly(vinyl pyrrolidone) having a structure of Formula (XI): (Formula XI), (vi) aof Formula (XII): (Formula XII), and / orof Formula (XIII):2101715-001234 -49-(Formula XIII), wherein each of a, b, c, d, e, f, and g are independently a rational number selected from the range of 10 to 5000, 15 to 4000, 20 to 3500, 30 to 3000, 40 to 2500, or 45 to 2270.

8. The composition according to claim 1, wherein the composition comprises one or more nanoparticles containing gold, a metal oxide, a metal carbide, a metal nitride, a metal boride, a metal dichalcogenide, boron nitride, graphene oxide, mesoporous silica, a conducting ceramic, or any combination thereof.

9. The composition according to claim 8, wherein the metal oxide comprises lithium oxide (Li2O), aluminum oxide (Al2O3), iron oxide (Fe2O3), calcium oxide (CaO), magnesium oxide (MgO), zinc oxide (ZnO), barium oxide (BaO), potassium oxide (K2O), sodium oxide (Na2O), nickel oxide (NiO), copper oxide (CuO), lead oxide (PbO), gold oxide (Au2O3), or titania (TiO2).

10. The composition according to claim 8, wherein the conducting ceramic comprises lithium sulfide-phosphorus pentasulfide (Li2S-P2S5), lithium zinc phosphate [LiZr2(PO4)3], or lithium lanthanum zirconate (Li7La3Zr2O12).

11. A solid-state electrolyte comprising the composition according to any one of the claims 1-10.

12. The solid-state electrolyte according to claim 11, wherein the electrolyte contains a mobile cation selected from an imidazolium, an aluminum ion, an iron ion, a lithium ion, a sodium ion, a potassium ion, a magnesium ion, a calcium ion, a nickel ion, a barium ion, a copper ion, a lead ion, a gold ion, a titanium ion, or any combination thereof.2101715-001234 -50- 13. The solid-state electrolyte according to claim 12, wherein the electrolyte comprises a flexible ion-conducting polymer containing ether oxygen-containing side chains, and a molar concentration of ether oxygen units ([EO]) and lithium ions ([Li+]) ([EO]:[Li], r) in a range of 5:1 < r < 30:

1.

14. The solid-state electrolyte according to claim 13, wherein the electrolyte comprises a glassy SIC polymer that has a number-average molecular weight (Mn) in a range of 6 to 105 kg / mol, and a structure containing a group of Formula (I) and / or Formula (II), wherein R is an ethylene methacrylate of Formula (III), wherein o is selected from 0.5, 1.0, 1.5, or 2, A- is (trifluoromethanesulfonyl)imide, and B+is Li+.

15. The solid-state electrolyte according to claim 13, wherein the electrolyte has an ionic conductivity of at least 7×10−3Scm−1at 150 °C.

16. The solid-state electrolyte according to claim 13, wherein the electrolyte has a Li+transference number of at least 0.

9.

17. The solid-state electrolyte according to claim 13, wherein the electrolyte has an electrochemical stability window of at least 4.7 V against Li+ / Li.

18. A device comprising an anode, a cathode, and a solid-state electrolyte according to claim 11.

19. The device according to claim 18, wherein the device comprises a solid-state electrolyte containing an imidazolium ionic liquid, an aluminum salt, an iron salt, a lithium salt, a sodium salt, a potassium salt, a magnesium salt, a calcium salt, a nickel salt, a barium salt, a copper salt, a lead salt, a gold salt, a titanium salt, or any combination thereof.

20. The device according to claim 18, wherein the device is a primary battery, a secondary battery, or a supercapacitor.

21. The device of claim 18, wherein the device is an alkali-ion conducting solid-state rechargeable battery comprising a lithium–ion battery, a lithium iron phosphate battery, a nickel–cadmium battery, a nickel–zinc battery, a nickel–metal hydride battery, a zinc–air battery, a lead–acid battery, or an alkaline battery.2101715-001234 -51- 22. The device of claim 18, wherein the cathode comprises a material chosen from alkali metal-containing cathode materials and conversion-type cathode materials.

23. The device of claim 18, wherein the anode comprises a material chosen from alkali metal-containing anode materials, silicon, graphite, and combinations thereof.

24. The device of claim 18, wherein the cathode comprises a conversion type material chosen from sulfur, sulfur composite materials, polysulfide materials, air, iodine, and metal sulfides; and / or wherein the anode comprises a material chosen from silicon-containing materials, tin and its alloys, tin / carbon, and phosphorus.

25. The device of claim 18, wherein the device comprises a liquid or gel electrolyte.

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