Poly(ethylene oxide) (PEO)‐based electrolytes are promising for all‐solid‐state batteries but can only be used above room temperature due to the high‐degree crystallization of PEO and the intimate ...affinity between ethylene oxide (EO) chains and lithium ions. Here, a homogeneous‐inspired design of PEO‐based solid‐state electrolytes with fast ion conduction is proposed. The homogeneous PEO‐based solid‐state electrolyte with an adjusted succinonitrile (SN) and PEO molar ratio simultaneously suppresses the PEO crystallization and mitigates the affinity between EO and Li+. By adjusting the molar ratio of SN to PEO (SN:EO ≈ 1:4), channels providing fast Li+ transport are formed within the homogeneous solid‐state polymer electrolyte, which increases the ionic conductivity by 100 times and enables their application at a low temperature (0–25 °C), together with the uniform lithium deposition. This modified PEO‐based electrolyte also enables a LiFePO4 cathode to achieve a superior Coulombic efficiency (>99%) and have a long life (>750 cycles) at room temperature. Moreover, even at a low temperature of 0 °C, 82% of its room‐temperature capacity remains, demonstrating the great potential of this electrolyte for practical solid‐state lithium battery applications.
Homogeneous‐inspired design of solid‐state polymer electrolytes with fast ion conduction is proposed. By adjusting the molar ratio of succinonitrile to poly(ethylene oxide) (SN:EO≈1:4), channels providing fast Li+ transport are formed within the homogeneous solid‐state polymer electrolyte, which increases the ionic conductivity by 100 times and enables their application at a low temperature (0–25 °C).
Flexible and low-cost poly(ethylene oxide) (PEO)-based electrolytes are promising for all-solid-state Li-metal batteries because of their compatibility with a metallic lithium anode. However, the low ...room-temperature Li-ion conductivity of PEO solid electrolytes and severe lithium-dendrite growth limit their application in high-energy Li-metal batteries. Here we prepared a PEO/perovskite Li3/8Sr7/16Ta3/4Zr1/4O₃ composite electrolyte with a Li-ion conductivity of 5.4 × 10−5 and 3.5 × 10−4 S cm−1 at 25 and 45 °C, respectively; the strong interaction between the F⁻ of TFSI⁻ (bistrifluoromethanesulfonimide) and the surface Ta5+ of the perovskite improves the Li-ion transport at the PEO/perovskite interface. A symmetric Li/composite electrolyte/Li cell shows an excellent cyclability at a high current density up to 0.6 mA cm−2. A solid electrolyte interphase layer formed in situ between the metallic lithium anode and the composite electrolyte suppresses lithium-dendrite formation and growth. All-solid-state Li|LiFePO₄ and high-voltage Li|LiNi0.8Mn0.1Co0.1O₂ batteries with the composite electrolyte have an impressive performance with high Coulombic efficiencies, small overpotentials, and good cycling stability.
In this study, the polyethylene oxide (PEO)/SiO2 nanoparticles (NPs) nanocomposite films with various SiO2 NPs concentrations were prepared using an in situ formation of NPs in the polymer matrix for ...self‐cleaning antireflected surface applications. The effect of SiO2 NPs in PEO/SiO2 NPs nanocomposite films on the structural, morphological, chemical, thermal, optical, and electrical properties of PEO/SiO2 NPs nanocomposite films was performed. According to the x‐ray diffraction and the differential scanning calorimetry analysis, the crystallinity degree of the nanocomposite films decreases by increasing the SiO2 NPs concentrations. The bandgap energy of PEO/SiO2 NPs nanocomposite films decreases from 3.95 to 3.55 eV as the SiO2 NPs concentration increases up to 10 wt.%. The average electrical conductivity of the PEO/SiO2 NPs nanocomposite films increases from 5.1 × 10−7 to 2.0 × 10−6 S/cm as the SiO2 NPs concentration increases up to 10 wt.%. The refractive index decreases to 1.64 at 550 nm for the PEO/SiO2 NPs nanocomposite films with 10 wt.% of SiO2 NPs, and the water contact angle decreases to around 0° after thermal treatment, which confirms that the PEO/SiO2 NPs nanocomposite films can be used as self‐cleaning antireflected surfaces.
Morphological and particle dispersion of PEO/SiO2 nanocomposite films.
Rechargeable batteries paired with sodium metal anodes are considered to be one of the most promising high-energy and low-cost energy-storage systems. However, the use of highly reactive sodium metal ...and the formation of sodium dendrites during battery operation have caused safety concerns, especially when highly flammable liquid electrolytes are used. Here we design and develop solvent-free solid polymer electrolytes (SPEs) based on a perfluoropolyether-terminated polyethylene oxide (PEO)-based block copolymer for safe and stable all-solid-state sodium metal batteries. Compared with traditional PEO SPEs, our results suggest that block copolymer design allows for the formation of self-assembled nanostructures leading to high storage modulus at elevated temperatures with the PEO domains providing transport channels even at high salt concentration (ethylene oxide/sodium = 8/2). Moreover, it is demonstrated that the incorporation of perfluoropolyether segments enhances the Na+ transference number of the electrolyte to 0.46 at 80 °C and enables a stable solid electrolyte interface. The new SPE exhibits highly stable symmetric cell-cycling performance at high current density (0.5 mA cm−2 and 1.0 mAh cm−2, up to 1,000 h). Finally, the assembled all-solid-state sodium metal batteries demonstrate outstanding capacity retention, long-term charge/discharge stability (Coulombic efficiency, 99.91%; >900 cycles with Na3V2(PO4)3 cathode) and good capability with high loading NaFePO4 cathode (>1 mAh cm−2).Rechargeable batteries with sodium metal anodes are promising as energy-storage systems despite safety concerns related to reactivity and dendrite formation. Solvent-free perfluoropolyether-based electrolytes are now reported for safe and stable all-solid-state sodium metal batteries.
Four types of Li1.5Al0.5Ge1.5(PO4)3 (LAGP) with different particle sizes are selected as active fillers incorporated into polyethylene oxide (PEO) matrix to fabricate PEO/LAGP hybrid electrolytes at ...drying room. The results show that LAGP particles have a positive effect on the ionic conductivity, lithium ion transference number, electrochemical stabilities and mechanical properties. Among the PEO/LAGP hybrid electrolytes, the PEO-20%LAGP-I hybrid electrolyte exhibits a maximum ionic conductivity of 6.76×10−4Scm−1 and an electrochemical window of 0–5.3V at 60°C. The possible reasons for conductivities improving are discussed through characterizing the phase transition behaviors of electrolytes. All-solid-state battery LiFePO4/Li is fabricated and presents fascinating electrochemical performance with high capacity retention (close to 90% after 50cycles at 60°C) and attractive capacities of 166, 155, 143 and 108mAhg−1 at current rates of 0.1, 0.2, 0.5 and 1 C, respectively. This work provides a promising PEO/LAGP hybrid electrolyte prepared by a simple method which can be manufactured easily in industry scale.
•A promising PEO/LAGP hybrid electrolyte prepared by a simple method which can be manufactured easily in industry scale.•The electrolyte exhibits an ionic conductivity of 6.76×10−4Scm−1 and an electrochemical window of 0-5.3V at 60°C.•The hybrid electrolyte has improved electrochemical and mechanical properties.•All-solid-state battery exhibits high capacity retention and attractive capacities.
Li+‐conducting oxides are considered better ceramic fillers than Li+‐insulating oxides for improving Li+ conductivity in composite polymer electrolytes owing to their ability to conduct Li+ through ...the ceramic oxide as well as across the oxide/polymer interface. Here we use two Li+‐insulating oxides (fluorite Gd0.1Ce0.9O1.95 and perovskite La0.8Sr0.2Ga0.8Mg0.2O2.55) with a high concentration of oxygen vacancies to demonstrate two oxide/poly(ethylene oxide) (PEO)‐based polymer composite electrolytes, each with a Li+ conductivity above 10−4 S cm−1 at 30 °C. Li solid‐state NMR results show an increase in Li+ ions (>10 %) occupying the more mobile A2 environment in the composite electrolytes. This increase in A2‐site occupancy originates from the strong interaction between the O2− of Li‐salt anion and the surface oxygen vacancies of each oxide and contributes to the more facile Li+ transport. All‐solid‐state Li‐metal cells with these composite electrolytes demonstrate a small interfacial resistance with good cycling performance at 35 °C.
The strong interaction between the surface oxygen vacancies of GDC/LSGM and the TFSI− anions in the composite polymer electrolyte changes Li+ distribution in two local environments, and the population increase of mobile Li+ ions in A2 significantly enhances the Li+ conductivity of the composite electrolyte.
Solid‐state polymer electrolytes (SPEs) suffer from the low ionic conductivity and poor capability of suppressing lithium (Li) dendrites, which limits their utility in the preparation of all ...solid‐state Li‐metal batteries (LMBs). It is reported here a flexible solid supramolecular electrolyte that incorporates a new anion capture agent, namely a phenylboronic acid functionalized calix4pyrrole (C4P), into a poly(ethylene oxide) (PEO) matrix. The resulting solid‐state supramolecular electrolyte demonstrates high ionic conductivity (1.9 × 10−3 S cm−1 at 60 °C) and a high Li+ transference number (tLi+${t}_{{\mathrm{Li}}^{\mathrm{ + }}}$ = 0.70). Furthermore, the assembled Li|C4P‐PEO‐LiTFSI|LiFePO4 cell allows for stable cycling over 1200 cycles at 1 C at 60 °C, as well as good rate performance. The favorable performance of the C4P‐PEO‐LiTFSI SPE leads to suggest it can prove useful in the creation of high energy density solid‐state LMBs.
Invited for the cover of this issue are Tomoki Ogoshi and co‐workers at Kyoto University, Kanazawa University and Tokyo University of Agriculture and Technology. The image depicts musical notation to ...represent hydrogen bond networks and poly(ethylene oxide) chains. Read the full text of the article at 10.1002/chem.202005099.
Poloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains ...of poly(ethylene oxide). Some chemical characteristics of poloxamers such as temperature-dependent self-assembly and thermo-reversible behavior along with biocompatibility and physiochemical properties make poloxamer-based biomaterials promising candidates for biomedical application such as tissue engineering and drug delivery. The microstructure, bioactivity, and mechanical properties of poloxamers can be tailored to mimic the behavior of various types of tissues. Moreover, their amphiphilic nature and the potential to self-assemble into the micelles make them promising drug carriers with the ability to improve the drug availability to make cancer cells more vulnerable to drugs. Poloxamers are also used for the modification of hydrophobic tissue-engineered constructs. This article collects the recent advances in design and application of poloxamer-based biomaterials in tissue engineering, drug/gene delivery, theranostic devices, and bioinks for 3D printing.
Poloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). The microstructure, bioactivity, and mechanical properties of poloxamers can be tailored to mimic the behavior of various types of tissues. Moreover, their amphiphilic nature and the potential to self-assemble into the micelles make them promising drug carriers with the ability to improve the drug availability to make cancer cells more vulnerable to drugs. However, no reports have systematically reviewed the critical role of poloxamer for biomedical applications. Research on poloxamers is growing today opening new scenarios that expand the potential of these biomaterials from “traditional” treatments to a new era of tissue engineering. To the best of our knowledge, this is the first review article in which such issue is systematically reviewed and critically discussed in the light of the existing literature.
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Abstract
Poly(ethylene oxide)-based solid-state electrolytes are widely considered promising candidates for the next generation of lithium and sodium metal batteries. However, several challenges, ...including low oxidation resistance and low cation transference number, hinder poly(ethylene oxide)-based electrolytes for broad applications. To circumvent these issues, here, we propose the design, synthesis and application of a fluoropolymer, i.e., poly(2,2,2-trifluoroethyl methacrylate). This polymer, when introduced into a poly(ethylene oxide)-based solid electrolyte, improves the electrochemical window stability and transference number. Via multiple physicochemical and theoretical characterizations, we identify the presence of tailored supramolecular bonds and peculiar morphological structures as the main factors responsible for the improved electrochemical performances. The polymeric solid electrolyte is also investigated in full lithium and sodium metal lab-scale cells. Interestingly, when tested in a single-layer pouch cell configuration in combination with a Li metal negative electrode and a LiMn
0.6
Fe
0.4
PO
4
-based positive electrode, the polymeric solid-state electrolyte enables 200 cycles at 42 mA·g
−1
and 70 °C with a stable discharge capacity of approximately 2.5 mAh when an external pressure of 0.28 MPa is applied.
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