Deep eutectic solvent-based polymer electrolyte for solid-state lithium metal batteries

Poly(ethylene) oxide(PEO)-based electrolytes have been widely studied for solid-state lithium batteries while their ionic conductivity and lithium-ion transference number still need to be further improved.Herein, using the combined experimental and theoretical approach, we demonstrate a novel, solidstate PEO-deep eutectic solvent(DES) electrolyte for the first time. We found that the in situ formation of DES can reduce the crystallinity of PEO matrix and more Li+ions can move freely owing to the...     

3D flame-retardant skeleton reinforced polymer electrolyte for solid-state dendrite-free lithium metal batteries

For solid polymer electrolytes(SPEs), improving their mechanical and electrochemical properties is the key to obtaining batteries with higher safety and higher energy density. Herein, a novel synergistic strategy proposed is preparing a 3D flame-retardant skeleton(3DPA) and adding nano-multifunctional fillers(Li-ILs@ZIF-8). In addition to providing mechanical support for the polyethylene oxide(PEO) matrix,3DPA also has further contributed to the system’s flame retardancy and further improved the...     

Coordination-network-based ionic plastic crystal for anhydrous proton conductivity

An ionic coordination network consisting of protonated imidazole and anionic one-dimensional chains of Zn(2+) phosphate was synthesized. The compound possesses highly mobile ions in the crystal lattice and behaves as an ionic plastic crystal. The dynamic behavior provides a proton conductivity of 2.6 × 10(-4) S cm(-1) at 130 °C without humidity.     

Chloride solid-state electrolytes for all-solid-state lithium batteries

Journal of Solid State Electrochemistry - Chloride solid-state electrolytes (SSEs) with wide electrochemical windows, high room-temperature ionic conductivity, and good stability towards air have...     

Structure and multinuclear solid-state NMR of a highly birefringent lead-gold cyanide coordination polymer

The coordination polymer Pb(H2O)[Au(CN)2]2 (1) was synthesized by the reaction of KAu(CN)2 and Pb(NO3)2. The structure contains 1-D chains of lead(II)-OH2 linked via Au(CN)2(-) moieties, generating a 2-D slab; weak aurophilic interactions of 3.506(2) and 3.4885(5) A occur within and between slabs. The geometry about each lead(II) is bicapped trigonal prismatic, having six N-bound cyanides at the prism vertices and waters at two of the faces. Dehydration at 175 degrees C yields microcrystalline Pb[Au(CN)2]2 (2), which, along with 1, was examined by 13C, 15N, 1H, and 207Pb solid-state NMR methods. Two 15N resonances are assigned to the mu2-bridging and hydrogen-bonding cyanides in 1. Upon dehydration, the 207Pb NMR spectrum becomes axially symmetric and yields a reduced shielding span, indicating higher site symmetry, while the 13C and 15N spectra reveal a single cyanide. Although no single-crystal X-ray structure of 2 could be obtained, a structure is proposed on the basis of the NMR and X-ray powder data, consisting of a lead(II) center in a distorted square-prismatic environment, with cyanides present at each corner. The birefringence of single crystals of 1 is found to be 7.0 x 10(-2) at room temperature. This value is large compared to that of most optical materials and can be attributed to the anisotropy of the 2-D slabs of 1, with all CN bonds aligned in the same direction by the polarizable lead(II) center.     

Microcalorimetric in situ synthesis and the solid-state reaction enthalpy change for 1D CoII coordination polymer

Journal of Thermal Analysis and Calorimetry - One cobalt (II) coordination polymer, named as [Co(3,3′-BDA)(H2O)2]n (3,3′-H2BDA is 3,3′-dicarboxyl-2,2′-bipyridine), has been...     

A novel PEO-based composite solid-state polymer electrolyte with methyl group-functionalized SBA-15 filler for rechargeable lithium batteries

Functionalized molecular sieve SBA-15 with trimethylchlorosilane was used as an inorganic filler in a poly(ethyleneoxide) (PEO) polymer matrix to synthesize a composite solid-state polymer electrolyte (CSPE) using LiClO₄ as the doping salts, which is designated to be used for rechargeable lithium batteries. The methyl group-functionalized SBA-15 (^fSBA-15) powder possesses more hydrophobic characters than SBA-15, which improves the miscibility between the ^fSBA-15 filler and the PEO matrix. The interaction between the ^fSBA-15 and PEO polymer matrix was investigated by scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry. Linear sweep voltammetry and electrochemical impedance spectroscopy were employed to study the electrochemical stability windows, ionic conductivity, and interfacial stability of the CSPE. The temperature dependence of the change of the PEO polymer matrix in the CSPE from crystallization to amorphous phase was surveyed, for the first time, at different temperature by Fourier transform infrared emission spectroscopy. It has demonstrated that the addition of the ^fSBA-15 filler has improved significantly the electrochemical compatibility of the CSPE with a lithium metal electrode and enhanced effectively the ion conductivity of the CSPE. Dedicated to Professor Oleg Petrii on the occasion of his 70th birthday on August 24th, 2007.     

Printed solid-state electrolytes for form factor-free Li-metal batteries

With the ever-growing interest in ubiquitous smart electronics and the Internet of Things, the demand for high-energy-density power sources with aesthetic versatility has increased tremendously. High energy density Li-metal batteries have attracted considerable attention for fulfilling the high energy density requirement of smart electronics. To obtain form factor-free Li-metal batteries with both design diversity and electrochemical reliability, printed solid-state electrolytes are required as a key component because of their viability for the printing/solidification-based fabrication process and electrode-customized chemical/physical properties. This review presents an overview of printed solid-state electrolytes for form factor-free Li-metal batteries with a focus on materials chemistry and fabrication requirements. In addition, their structural/physical/electrochemical properties were discussed in terms of compatibility with Li-metal batteries.     

Cellulose acetate-promoted polymer-in-salt electrolytes for solid-state lithium batteries

Journal of Solid State Electrochemistry - Despite their non-flammability, low processing cost and wide electrochemical stability window, solid-state polymer electrolytes still exhibit certain...     

Synthesis and proton conductivity of anhydrous dendritic electrolytes

Water soluble PEG cored dendritic hexa-acid which comprises peripheral carboxylic acidic groups were prepared via nucleophilic substitution reactions. Novel anhydrous proton conducting electrolytes were prepared by incorporation of the heterocyclic protogenic solvent imidazole (Im) into PEG cored dendritic hexa acid, (PEG-HA), at several molar ratios of Im to-COOH units of PEG-HA. The complexation of PEG-HA and Im was illustrated by infrared spectroscopy (FT-IR). The materials are thermally stable up to 150 °C as evidenced by thermogravimetry analysis (TGA). Differential scanning calorimetry (DSC) results verified that the organic electrolytes are homogeneous and amorphous. The proton conductivities were characterized by means of AC impedance spectroscopy and a maximum conductivity of 1 × 10⁻³ S/cm was measured at 120 °C in the anhydrous state.      

Recent advances of composite electrolytes for solid-state Li batteries

All-solid-state lithium batteries(ASSLBs) are recognized as high energy density batteries system without safety issues within the next generation of batteries. The development of solid electrolytes is the crucial step of ASSLBs. The composite electrolyte has stable physical and electrochemical characteristics, and its comprehensive performance surpasses the individual solid electrolyte, bringing unique vitality to the solid electrolyte. However, their intrinsic weakness limits the development of...     

Solvent-free low-dimensional polymer electrolytes for lithium-polymer batteries

The development of solvent-free low-dimensional polymer electrolytes intended for use in solvent-free lithium batteries operating at ambient or sub-ambient temperatures is described. The synthetic routes to the amphiphilic polymers I having 5-alkoxy-3,4-phenylene units connected with oligoethoxy segments via polyester-ether or pure polyether links (abbrev. CmOn, m = 12, 16, 18, n = 1-5) and to the copolymers CmO1-CmOn are described. The structures, thermal properties and SAXS long spacings of their complexes with lithium salts (type A) and with long chain n-alkane or alkyl side chain intercalation (type B) are discussed. However, high ambient conductivities (10(-4)-10(-3) S cm(-1)) are observed in type C systems when a second copolymer based on polytetramethylene oxide segments (II) is incorporated as a microphase between the lamellae of I and serving as an ion bridge or "glue". DC polarization between Li electrodes also gives ambient conductivities >/=ca.10(-3) S cm(-1). In type D systems the I/II interface is stabilized by including a copolymer III, promoting high reproducibility in performance. Copolymers I of CmO1-CmO5 having CmO1 in excess give optimum conductivities with low temperature-dependence. This, together with molecular modeling, suggests uncoupled ion mobilities by hopping between small aggregates in the interlamellar spaces.     

Polycarbonates as alternative electrolyte host materials for solid-state sodium batteries

This paper describes the first implementation of the aliphatic polycarbonate PTMC – that has previously been successfully applied to lithium polymer batteries – as a non-polyether host matrix in solid-state sodium batteries. Despite higher glass transition temperatures of PTMC–NaTFSI and PTMC–NaClO₄ electrolytes than their Li-containing counterparts, the ionic conductivities were found to be similar to the equivalent Li salt electrolytes. Finally, the functionality of PTMC–NaTFSI was demonstrated through cycling of Na/Prussian blue half-cells displaying high discharge capacities and limited polarization at C/10 and 60 °C.     

Enhancing interfacial stability in solid-state lithium batteries with polymer/garnet solid electrolyte and composite cathode framework

The solid-state lithium battery is considered as an ideal next-generation energy storage device owing to its high safety,high energy density and low cost.However,the poor ionic conductivity of solid electrolyte and low interfacial stability has hindered the application of solid-state lithium battery.Here,a flexible polymer/garnet solid electrolyte is prepared with poly(ethylene oxide),poly(vinylidene fluoride),Li6.75La3 Zr1.75Ta0.25O12,lithium bis(trifluoromethanesulfonyl)imide and oxalate,which exhibits an ionic conductivity of 2.0 ×10^-4 S cm^-1 at 55℃,improved mechanical property,wide electrochemical window(4.8 V vs.Li/Li+),enhanced thermal stabilities.Tiny acidic OX was introduced to inhibit the alkalinity reactions between Li6.75La3 Zr1.75Ta0.25O12 and poly(vinylidene fluoride).In order to improve the interfacial stability between cathode and electrolyte,an Al2 O3@LiNi0.5Co0.2Mn0.3O2 based composite cathode framework is also fabricated with poly(ethylene oxide) polymer and lithium salt as additives.The solid-state lithium battery assembled with polymer/garnet solid electrolyte and composite cathode framework demonstrates a high initial discharge capacity of 150.6 mAh g^-1 and good capacity retention of 86.7% after 80 cycles at 0.2 C and 55℃,which provides a promising choice for achieving the stable electrode/electrolyte interfacial contact in solid-state lithium batteries.     

Recent advances in solid-state beyond lithium batteries

Journal of Solid State Electrochemistry - As battery technologies are in continuous development, and especially due to the rapid growth in vehicle electrification, which requires large (e.g.,...     

Irreversible replacement of sodium with thallium in sodium coordination polymer nanostructures by solid-state mechanochemical cation exchange process

Solid-state conversion of Na^I coordination polymer nanostructure, synthesized by sonochemical procedure, to Tl^I coordination polymer has been observed upon liquid-assisted mechanochemical reaction of [Na₂TP] _n (1) (H₂TP = terephthalic acid), with TlNO₃. During this conversion, ion exchange process of Na(I) with Tl(I) was occurred and [Tl₂TP] _n (2) was synthesized. The X-ray diffraction (XRD) pattern of 2 after mechanochemical reaction of it with NaNO₃ indicated that this transformation is irreversible. Compounds 1 and 2 were characterized by IR spectroscopy, X-ray powder diffraction (XRD), elemental analysis, thermogravimetric and differential thermal analyses and scanning electron microscopy.     

Structural characterization of an anhydrous polymorph of paclitaxel by solid-state NMR

The three-dimensional structure of a unique polymorph of the anticancer drug paclitaxel (Taxol) is established using solid state NMR (SSNMR) tensor ((13)C & (15)N) and heteronuclear correlation ((1)H-(13)C) data. The polymorph has two molecules per asymmetric unit (Z' = 2) and is thus the first conformational characterization with Z' > 1 established solely by SSNMR. Experimental data are correlated with structure through a series of computational models that extensively sample all conformations. For each computational model, corresponding tensor values are computed to supply comparisons with experimental information which, in turn, establishes paclitaxel's structure. Heteronuclear correlation data at thirteen key positions provide shift assignments to the asymmetric unit for each comparison. The two distinct molecules of the asymmetric unit possess nearly identical baccatin III moieties with matching conformations of the C10 acetyl moiety and, specifically, the torsion angle formed by C30-O-C10-C9. Additionally, both are found to exhibit an extended conformation of the phenylisoserine sidechain at C13 with notable differences in the dihedral angles centered around the rotation axes of O-C13, C2'-C1' and C3'-C2'.     

A simple solid-state pH glass electrode

A modernized version of the thompson electrode is described. A copper wire is connected to the inner surface of the membrane of a glass electrode with a conductive adhesive resin.     

Designing composite polymer electrolytes for all-solid-state lithium batteries

Ceramic fast-ion conductors have high ionic conductivities (>10^?4 S cm^?1) but are difficult to process and have poor chemo/mechanical properties at the electrode/electrolyte interfaces. In contrast, polymer electrolytes are pliable and easy to process but suffer from low room-temperature ionic conductivities (≈10^?6-10^?7 S cm^?1). Combining these two elements to form a composite polymer electrolyte is a promising way to enable all-solid-state lithium-metal batteries. The choice of ceramic filler and polymer can be tailored to provide synergistic benefits that overcome the practical shortcomings of the two components. Herein, the fundamentals of Li⁺ conduction through the various phases and interfaces in these materials are discussed as well as the important parameters, beyond the initial choice of polymer and ceramic filler materials that must be considered while designing composite polymer electrolytes. Emphasis is placed on the particle filler engineering and practical fabrication methods as routes toward enhancing the properties of these composites.