Sol-Gel Non-hydrolytic Synthesis of a Nanocomposite Electrolyte for Application in Lithium-ion Devices

2004 ◽  
Vol 822 ◽  
Author(s):  
Flávio L. Souza ◽  
Paulo R. Bueno ◽  
Ronaldo C. Faria ◽  
Elson Longo ◽  
Edson R. Leite

AbstractA new nanocomposite electrolyte was synthesized using a simple non-hydrolytic sol-gel route without specific treatment of the reagents. The nanocomposite ion conductor was prepared with citric acid, tetraethyl orthosilicate and ethylene glycol, forming polyester chains. The time-consuming drying step that is a necessary part of most chemical syntheses was not required in the preparation of the present nanocomposite electrolyte of the polyelectrolyte class, because only Li+ is mobile in the polymeric chain. The effects of the concentration of Li, SiO 2 and SnO2nanoparticles were investigated in terms of Li+ ionic conductivity. Conductivity measurements as a function of the metal oxide nanocrystal content in the nanocomposite revealed a significant increase in conductivity at approximately 5 and 10 wt % of nanoparticles. The new nanocomposite conductor proved to be fully amorphous at room temperature, with a vitreous transition temperature of approximately 228K (−45°C). The material is solid and transparent, displaying an ionic conductivity of 10−4to 10−5 (O.cm)−1at room temperature presenting excellent reproducibility of all these characteristics. Cyclic voltammetry measurements indicate that the hybrid electrolyte possesses outstanding electrochemical stability.

2020 ◽  
Vol 13 (06) ◽  
pp. 2050031
Author(s):  
Yue Jiang ◽  
Zhiwei Hu ◽  
Ming’en Ling ◽  
Xiaohong Zhu

Since the lithium-ion conductor Li[Formula: see text]GeP2S[Formula: see text] (LGPS) with a super high room-temperature conductivity of 12[Formula: see text]mS/cm was first reported in 2011, sulfide-type solid electrolytes have been paid much attention. It was suggested by Kwon et al. [J. Mater. Chem. A 3, 438 (2015)] that some excess lithium ions in LGPS, namely, Li[Formula: see text]Ge[Formula: see text] P[Formula: see text]S[Formula: see text], could further improve their ionic conductivities, and the highest conductivity of 14.2[Formula: see text]mS/cm was obtained at [Formula: see text] though a larger lattice parameter that occurred at [Formula: see text]. In this study, we focus on these two different chemical compositions of LGPS with [Formula: see text] and [Formula: see text], respectively. Both samples were prepared using the same experimental process. Their lattice parameter, microstructure and room-temperature ionic conductivity were compared in detail. The results show that the main phase is the tetragonal LGPS phase but with a nearly identical amount of orthorhombic LGPS phase coexisting in both samples. Bigger lattice parameters, larger grain sizes and higher ionic conductivities are simultaneously achieved in Li[Formula: see text]Ge[Formula: see text]P[Formula: see text]S[Formula: see text] ([Formula: see text]), exhibiting an ultrahigh room-temperature ionic conductivity of 18.8[Formula: see text]mS/cm.


Membranes ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 109 ◽  
Author(s):  
Jadra Mosa ◽  
Jonh Fredy Vélez ◽  
Mario Aparicio

Organic/inorganic hybrid membranes that are based on GTT (GPTMS-TMES-TPTE) system while using 3-Glycidoxypropyl-trimethoxysilane (GPTMS), Trimethyletoxisilane (TMES), and Trimethylolpropane triglycidyl ether (TPTE) as precursors have been obtained while using a combination of organic polymerization and sol-gel synthesis to be used as electrolytes in Li-ion batteries. Self-supported materials and thin-films solid hybrid electrolytes that were doped with Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) were prepared. The hybrid network is based on highly cross-linked structures with high ionic conductivity. The dependency of the crosslinked hybrid structure and polymerization grade on ionic conductivity is studied. Ionic conductivity depends on triepoxy precursor (TPTE) and the accessibility of Li ions in the organic network, reaching a maximum ionic conductivity of 1.3 × 10−4 and 1.4 × 10−3 S cm−1 at room temperature and 60 °C, respectively. A wide electrochemical stability window in the range of 1.5–5 V facilitates its use as solid electrolytes in next-generation of Li-ion batteries.


2002 ◽  
Vol 756 ◽  
Author(s):  
Hideki Maekawa ◽  
Ryo Tanaka ◽  
Tsutomu Yamamura

ABSTRACTOrdered-mesoporous Al2O3 was synthesized by the sol-gel method using neutral surfactants as templates. The pore size can be controlled over the range of 2.8∼12.5 nm by using different surfactant copolymers and by different synthetic conditions. By utilizing cyclohexane as a co-solvent, mesoporous Al2O3 having relatively mono-dispersed particle size was obtained. Composites composed of the synthesized mesoporous Al2O3 and the lithium ion conductor (LiI) was prepared. The dc electrical conductivity of 50LiI ·50(mesoporous Al2O3) was 2.6×10-4 S cm-1 at room temperature, which is more than 100 times higher than that of pure LiI. The pore size dependence of the conductivity of LiI-mesoporous Al2O3 composite was examined. A systematic dependence of conductivity upon pore size was observed, in which the conductivity increased with decreasing the pore size.


1992 ◽  
Vol 293 ◽  
Author(s):  
Herve Cheradame ◽  
F. Desbat ◽  
P. Mercier-Niddam ◽  
S. Boileau

AbstractIonically conducting materials containing PEO were prepared from telechelic di(methyl-diethoxy-silane) PEO, synthesized by the hydrosilylation of telechelic diallyl-PEO with methyldiethoxysilane. The network is obtained by the usual sol-gel chemistry. Then, it is filled with LiClO4 by diffusion of the salt and further drying. A comparison is made with the same kind of materials crosslinked using urethane chemistry. Diffusion studies show that the diffusion coefficient of solvent is similar for both types of materials, whilst the ionic conductivity is higher for the networks crosslinked with siloxane bonds. An experiment of diffusion of LiClO4 without solvent showed that this salt has a diffusion coefficient of the order of 2.10-8 cm2.sec-1 at 34°C. The conductivity calculated from this determination is compatible with the mechanism of lithium cation transport by the diffusion of salt molecules. Elasticity modulus measurements show that the salt aggregates are essentially located within the crosslinks at low concentration, but also in the PEO chains for salt concentrations higher than 1 mol/l.


Membranes ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 186
Author(s):  
Mark D. Francisco ◽  
Cheng-Tang Pan ◽  
Bo-Hao Liao ◽  
Mao-Sung Wu ◽  
Ru-Yuan Yang ◽  
...  

Environmental and economic concerns are driving the demand for electric vehicles. However, their development for mass transportation hinges largely on improvements in the separators in lithium-ion batteries (LIBs), the preferred energy source. In this study, innovative separators for LIBs were fabricated by near-field electrospinning (NFES) and the sol-gel method. Using NFES, poly (vinylidene fluoride) (PVDF) fibers were fabricated. Then, PVDF membranes with pores of 220 nm and 450 nm were sandwiched between a monolayer and bilayer of the electrospun fibers. Nanoceramic material with organic resin, formed by the sol-gel method, was coated onto A4 paper, rice paper, nonwoven fabric, and carbon synthetic fabric. Properties of these separators were compared with those of a commercial polypropylene (PP) separator using a scanning electron microscope (SEM), microtensile testing, differential scanning calorimetry (DSC), ion-conductivity measurement, cyclic voltammetry (CV), and charge-discharge cycling. The results indicate that the 220 nm PVDF membrane sandwiched between a bilayer of electrospun fibers had excellent ionic conductivity (~0.57 mS/cm), a porosity of ~70%, an endothermic peak of ~175 °C, better specific capacitance (~356 mAh/g), a higher melting temperature (~160 °C), and a stable cycle performance. The sol-gel coated nonwoven fabric had ionic conductivity, porosity, and specific capacitance of ~0.96 mS/cm., ~64%, and ~220 mAh/g, respectively, and excellent thermal stability despite having a lower specific capacitance (65% of PP separator) and no peak below 270 °C. The present study provides a significant step toward the innovation of materials and processes for fabricating LIB separators.


2008 ◽  
Vol 1122 ◽  
Author(s):  
Gianguido Baldinozzi ◽  
David Simeone ◽  
Dominique Gosset ◽  
Mickael Dollé ◽  
Georgette Petot-Ervas

AbstractWe have synthesized Gd-doped ceria polycrystalline samples (5, 10, 15 %mol), having relative densities exceeding 95% and grain sizes between 30 and 160 nm after axial hot pressing (750 °C, 250 MPa). The samples were prepared by sintering nanopowders obtained by sol-gel chemistry methods having a very narrow size distribution centered at about 16 nm. SEM and X-ray diffraction were performed to characterize the sample microstructures and to assess their structures. We report ionic conductivity measurements using impedance spectroscopy. It is important to investigate the properties of these systems with sub-micrometric grains and as a function of their composition. Therefore, samples having micrometric and nanometric grain sizes (and different Gd content) were studied. Evidence of Gd segregation near the grain boundaries is given and the impact on the ionic conductivity, as a function of the grain size and Gd composition, is discussed and compared to microcrystalline samples.


2020 ◽  
Vol 20 (2) ◽  
Author(s):  
Qolby Sabrina ◽  
Titik Lestariningsih ◽  
Christin Rina Ratri ◽  
Achmad Subhan

Solid polymer electrolyte (SPE) appropriate to solve packaging leakage and expansion volume in lithium-ion battery systems. Evaluation of electrochemical performance of SPE consisted of mixture lithium salt, solid plasticizer, and polymer precursor with different ratio. Impedance spectroscopy was used to investigate ionic conduction and dielectric response lithium bis(trifluoromethane)sulfony imide (LiTFSI) salt, and additive succinonitrile (SCN) plasticizer. The result showing enhanced high ionic conductivity. In half-cell configurations, wide electrochemical stability window of the SPE has been tested. Have stability window at room temperature, indicating great potential of SPE for application in lithium ion batteries. Additive SCN contribute to forming pores that make it easier for the li ion to move from the anode to the cathode and vice versa for better perform SPE. Pore of SPE has been charaterization with FE-SEM. Additive 5% w.t SCN shows the best ionic conductivity with 4.2 volt wide stability window and pretty much invisible pores.


2013 ◽  
Vol 1496 ◽  
Author(s):  
Sumaletha Narayanan ◽  
Lina Truong ◽  
Venkataraman Thangadurai

ABSTRACTGarnet-type electrolytes are currently receiving much attention for applications in Li-ion batteries, as they possess high ionic conductivity and chemical stability. Doping the garnet structure has proved to be a good way to improve the Li ion conductivity and stability. The present study includes effects of Y- doping in Li5La3Nb2O12 on Li ion conductivity and stability of “Li5+2xLa3Nb2-xYxO12” (0.05 ≤ x ≤ 0.75) under various environments, as well as chemical stability studies of Li5+xBaxLa3-xM2O12 (M = Nb, Ta) in water. “Li6.5La3Nb1.25Y0.75O12” showed a very high ionic conductivity of 2.7 х 10−4 Scm−1 at 25 °C, which is comparable to the highest value reported for garnet-type compounds, e.g., Li7La3Zr2O12. The selected members show very good stability against high temperatures, water, Li battery cathode Li2CoMn3O8 and carbon. The Li5+xBaxLa3-xNb2O12 garnets have shown to readily undergo an ion-exchange (proton) reaction under water treatment at room temperature; however, the Ta-based garnet appears to exhibit considerably higher stability under the same conditions.


2019 ◽  
Vol 12 (06) ◽  
pp. 1930006 ◽  
Author(s):  
Chengjun Yi ◽  
Wenyi Liu ◽  
Linpo Li ◽  
Haoyang Dong ◽  
Jinping Liu

Solid-state polymer lithium-ion batteries with better safety and higher energy density are one of the most promising batteries, which are expected to power future electric vehicles and smart grids. However, the low ionic conductivity at room temperature of solid polymer electrolytes (SPEs) decelerates the entry of such batteries into the market. Creating polymer-in-salt solid electrolytes (PISSEs) where the lithium salt contents exceed 50[Formula: see text]wt.% is a viable technology to enhance ionic conductivity at room temperature of SPEs, which is also suitable for scalable production. In this review, we first clarify the structure and ionic conductivity mechanism of PISSEs by analyzing the interactions between lithium salt and polymer matrix. Then, the recent advances on polyacrylonitrile (PAN)-based PISSEs and polycarbonate derivative-based PISSEs will be reviewed. Finally, we propose possible directions and opportunities to accelerate the commercializing of PISSEs for solid polymer Li-ion batteries.


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