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1.
Solid polymer electrolyte films containing poly(vinyl alcohol) (PVA) and magnesium nitrate (Mg(NO3)2) were prepared by solution casting technique and characterized by using XRD, FTIR, DSC and AC impedance spectroscopic analysis. The amorphous nature of the polymer electrolyte films has been confirmed by XRD. The complex formation between PVA and Mg salt has been confirmed by FTIR. The glass transition temperature decreases with increasing the Mg salt concentration. The AC impedance studies are performed to evaluate the ionic conductivity of the polymer electrolyte films in the range of 303 383 K, and the temperature dependence seems to obey the Arrhenius behavior. Transport number measurements show that the charge transport is mainly due to ions. Electrochemical cell of configuration Mg/(PVA + Mg(NO3)2) (70:30)/(I2 + C + electrolyte) has been fabricated. The discharge characteristics of the cell were studied for a constant load of 100 kΩ. 相似文献
2.
An electrochemical capacitor utilizing a polyvinyl alcohol (PVA) and H4SiW12O40 (SiWA) solid polymer electrolyte was developed. The electrolyte was deposited via precursor solution coating followed by thermal pressing and exhibited an ionic conductivity of 0.01 S/cm. The electrolyte has also shown good stability and cycle life. The performance of the solid polymer electrolyte-based capacitor was characterized using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and was compared to a similar capacitor with an aqueous electrolyte. 相似文献
3.
Solid asymmetric electrochemical capacitors (EC) using polyvinyl alcohol (PVA)–heteropoly acid (HPA) electrolytes and RuO2–graphite electrodes were developed. The devices were about 0.2 mm thick and had a working voltage window of 0–1.5 V, 50% wider than that of any proton-conducting symmetric EC. Pseudocapacitance from HPA contributes to the total capacitance of the asymmetric EC within a certain potential window. The PVA–HPA polymers have been proven to function both as electrolyte and as pseudocapacitive electrode material in EC cells. 相似文献
4.
S. K. Tripathi Amrita Jain Ashish Gupta Manju Mishra 《Journal of Solid State Electrochemistry》2012,16(5):1799-1806
The development of polymer gel electrolyte system with high ionic conductivity is the main objective of polymer research.
Electrochemical devices based on lithium ion-conducting polymer electrolyte are not safe due to the explosive nature of lithium.
An attempt has been made to synthesize magnesium ion-conducting polymeric gel electrolytes, poly (vinylidene fluoride-co-hexafluoropropylene)–propylene
carbonate–magnesium perchlorate, PVdF(HFP)-PC–Mg(ClO4)2 using standard solution-cast techniques. The maximum room temperature ionic conductivity of the synthesized electrolyte system
has been observed to be 5.0 × 10−3 S cm−1, which is quite acceptable from a device fabrication point of view. The temperature-dependent conductivity and the dielectric
behavior were also analyzed. The pattern of the temperature-dependent conductivity shows the Arrhenius behavior. The dielectric
constant ε
r and dielectric loss ε
i increases with temperature in the low-frequency region but almost negligible in the high-frequency region. This behavior
can be explained on the basis of electrode polarization effects. The real part M
r
and imaginary part M
i
versus frequency indicate that the systems are predominantly ionic conductors. Further, the synthesized electrolyte materials
have been checked for its suitability in energy storage devices namely redox supercapacitor with conducting polymer polypyrrole
as electrode materials, and finally, it was observed that it shows good capacitive behavior in low-frequency region. Preliminary
studies show that the overall capacitance of 22 mF cm−2 which is equivalent to a single electrode specific capacitance of 117 F gm−1 was observed for the above said supercapacitors. 相似文献
5.
Wuu‐Jyh Liang Chao‐Ling Kuo Chia‐Liang Lin Ping‐Lin Kuo 《Journal of polymer science. Part A, Polymer chemistry》2002,40(9):1226-1235
Two series of novel crosslinked siloxane‐based polymers and their complexes with lithium perchlorate (LiClO4) were prepared and characterized by Fourier transform infrared spectroscopy, solid‐state NMR (13C, 29Si, and 7Li nuclei), and differential scanning calorimetry. Their thermal stability and ionic conductivity of these complexes were also investigated by thermogravimetric and AC impedance measurements. In these polymer networks, poly(propylene oxide) chains with different molecular weights were introduced through self‐synthesized epoxy‐siloxane precursors cured with two curing agents. The glass‐transition temperature (Tg) of these copolymers is dependent on the length of the ether units. The dissolution of LiClO4 considerably increases the Tg of the polyether segments. The dependence of the ionic conductivity was investigated as a function of temperature, LiClO4 concentration, and the molecular weight of the polyether segments. The ion‐transport behavior was affected by the combination of the ionic mobility and number of carrier ions. The 7Li solid‐state NMR line shapes of these polymer complexes suggest a significant interaction between Li+ ions and the polymer matrix, and temperature‐ and LiClO4 concentration‐dependent chemical shifts are correlated with ionic conductivity. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1226–1235, 2002 相似文献
6.
Jiří Vondrák Marie Sedlaříková Jiří Libich Michal Jahn 《Journal of Solid State Electrochemistry》2017,21(9):2615-2620
This paper explains some properties of gel polymer electrolytes, which are mostly used in lithium ion batteries. An emphasis is laid on the internal structure and its influence on the mobility of ions in the substance. The ions are solvated and located randomly in the liquid base of the gel, and their movement is predominantly determined by the Stokes law for liquid electrolytes. Polymethylmethacrylate gel is used as a model substance here. This report is based on the experience of the authors and their associates. 相似文献
7.
Chih‐Hao Tsao Mitsuru Ueda Ping‐Lin Kuo 《Journal of polymer science. Part A, Polymer chemistry》2016,54(3):352-358
A new method to prepare the polymer electrolytes for lithium‐ion batteries is proposed. The polymer electrolytes were prepared by reacting poly(phosphazene)s (MEEPP) having 2‐(2‐methoxyethoxy)ethoxy and 2‐(phenoxy)ethoxy units with 2,4,6‐tris[bis(methoxymethyl)amino]‐1,3,5‐triazine (CYMEL) as a cross‐linking agent. This method is simple and reliable for controlling the cross‐linking extent, thereby providing a straightforward way to produce a flexible polymer electrolyte membrane. The 6 mol % cross‐linked polymer electrolyte (ethylene oxide unit (EO)/Li = 24:1) exhibited a maximum ionic conductivity of 5.36 × 10?5 S cm?1 at 100 °C. The 7Li linewidths of solid‐state static NMR showed that the ionic conductivity was strongly related to polymer segment motion. Moreover, the electrochemical stability of the MEEPP polymer electrolytes increased with an increasing extent of cross‐linking, the highest oxidation voltage of which reached as high as 7.0 V. Moreover, phenoxy‐containing polyphosphazenes are very useful model polymers to study the relationship between the polymer flexibility; that is, the cross‐linking extent and the mobility of metal ions. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 352–358 相似文献
8.
9.
《Progress in Solid State Chemistry》2014,42(4):85-105
An overview is presented on the development of improved polymer based electrolytes during the past years. The emphasis lies on new approaches regarding chemical concepts that achieve a higher total conductivity and lithium transference number as well as an increased electrochemical, mechanical and thermal stability. With respect to the polymer chemistry, the focus is laid on siloxane and phosphazene derived systems. Topics are the chemical modification of the polymeric, cyclic and low molecular derivates of these systems, the formation of stable membranes from these by suitable cross-linking strategies and an extensive electrochemical characterization in corresponding lithium cells. Recent trends towards composite and hybrid materials are illustrated with examples and newly developed hybrid electrolytes. A particular chance for improvements comes from the design and use of stable small molecular additives in combination with optimized and electrochemically stable polymer networks. Special compounds are introduced which may act themselves as novel solvents with increased electrochemical stabilities. The relevance of chosen lithium salts for polymer electrolytes is discussed, too, and a new family of pyrazolide anions is introduced. In all cases, the electrochemical performance has been characterized by standard experimental techniques. 相似文献
10.
Proton-conducting polymer membranes are utilized as the solid electrolyte in low temperature polymer electrolyte fuel cells (PEFC), which are efficient energy converters. We have selected the process of radiation grafting and subsequent sulfonation to prepare novel membranes because of its feasibility as a low cost production method. Investigations of the two first preparations steps, i.e., irradiation and grafting, lead to insight concerning the optimization of these two steps and the dependence of the final membrane properties on the various preparation parameters. 相似文献
11.
Magnetoelectric polymer nanocomposite structures are synthesized using conducting polyaniline and nanosized BFO particles through in situ sol–gel polymerization. The effect of nanosized BFO in polyaniline matrix is studied. The SEM, XRD, VSM, FTIR, and UV–Vis studies were made to understand the morphology, crystalline structure, magnetic, and optical properties of PANI/BFO composites with various concentrations of nanofiller. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2418–2422, 2008 相似文献
12.
硅氧烷基聚合物电解质* 总被引:1,自引:0,他引:1
聚合物锂离子电池的核心技术是研制高离子传导率、适宜机械性能以及化学和电化学性能稳定的聚合物电解质材料。在众多寻求高性能聚合物电解质的研究工作中,由于硅氧烷基聚合物电解质具有灵活多样的分子结构设计、易于合成实施、优异的电化学性能和室温电导率等特点,一直是人们关注的热点领域。本文综述了近年来新型硅氧烷基聚合物电解质的设计与合成的研究工作,重点介绍了采用聚硅氧烷嵌段、接枝聚合物通过共混、互穿网络结构、交联网络结构以及无机-有机复合等方法开展的相关聚合物电解质的研究工作。同时也介绍了聚硅氧烷电解质的研究方法和基于聚硅氧烷电解质的应用研究进展。 相似文献
13.
Hee-Jin Ryoo Hee-Tak Kim Young-Gi Lee Jung-Ki Park Seong-In Moon 《Journal of Solid State Electrochemistry》1998,3(1):1-6
The thermal and electrochemical characteristics of plasticized polymer electrolytes composed of poly(acrylonitrile-co-methyl methacrylate) [P(AN-co-MMA)], a plasticizer [a mixture of ethylene carbonate and propylene carbonate], and LiCF3SO3 were investigated. The incorporation of a MMA unit into the matrix polymer was effective for an increase in the compatibility
between the matrix polymer and the plasticizer. The comparative investigation of the interfacial resistance of the Li/polymer
electrolyte/Li cell for the PAN-based and the P(AN-co-MMA)-based polymer electrolytes showed that the MMA unit could improve the stability of the polymer electrolyte toward the
Li electrode, which is probably due to the enhanced adhesion of the polymer electrolyte to the Li electrode.
Received: 14 July 1997 / Accepted: 14 May 1998 相似文献
14.
Highly concentrated polycarbonate‐based solid polymer electrolytes having extraordinary electrochemical stability
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Kento Kimura Joh Motomatsu Yoichi Tominaga 《Journal of Polymer Science.Polymer Physics》2016,54(23):2442-2447
Solid polymer electrolytes (SPEs) are compounds of great interest as safe and flexible alternative ionics materials, particularly suitable for energy storage devices. We study an unusual dependence on the salt concentration of the ionic conductivity in an SPE system based on poly(ethylene carbonate) (PEC). Dielectric relaxation spectroscopy reveals that the ionic conductivity of PEC/lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) electrolyte continues to increase with increasing salt concentration because the segmental motion of the polymer chains is enhanced by the plasticizing effect of the imide anion. Fourier transfer‐infrared (FTIR) spectroscopy suggests that this unusual phenomenon arises because of a relatively loose coordination structure having moderately aggregated ions, in contrast to polyether‐based systems. Comparative FTIR study against PEC/lithium perchlorate (LiClO4) electrolytes suggests that weak ionic interaction between Li and TFSI ions is also important. Highly concentrated electrolytes with both reasonable conductivity and high lithium transference number (t+) can be obtained in the PEC/LiTFSI system as a result of the unusual salt concentration dependence of the conductivity and the ionic solvation structure. The resulting concentrated PEC/LiTFSI electrolytes have extraordinary oxidation stability and prevent any Al corrosion reaction in a cyclic voltammetry. These are inherent effects of the highly concentrated salt. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2442–2447 相似文献
15.
The synthesis of the first donor-acceptor phenylazomethine dendrimers (4 and 5) is described. A convergent method is used via the condensation of aromatic ketones with an appropriately functionalized tri(aminophenyl)-s-triazine promoted by titanium (IV) chloride. Cyclic voltammetry investigations show a donor-acceptor behaviour due to the presence of the electron acceptor s-triazine core and the donor ability of the conjugated peripheral butoxybenzene units. 相似文献
16.
Öztürk Tuğçe Pınar Gelir Ali Keshtiban Nahid Aghabalapoor Yargı Önder Özdemir Onur B. Mucur Selin Pıravadılı Seçgin Alper 《Journal of Solid State Electrochemistry》2023,27(4):885-894
Journal of Solid State Electrochemistry - The motion of the ion pairs under the applied electric field is an important phenomenon in the storage properties of the capacitive devices. In this study,... 相似文献
17.
C. M. Cheng F. J. Micale J. W. Vanderhoff M. S. El-Aasser 《Journal of polymer science. Part A, Polymer chemistry》1992,30(2):235-244
Monodisperse porous polymer particles in the size range of 10 μm in diameter were prepared via seeded emulsion polymerization. Linear polymer (polystyrene seed) or a mixture of linear polymer and solvent or nonsolvent were used as inert diluents. The pore diameters of these porous polymer particles were on the order of 1000 Å with pore volumes up to 0.9 mL/g and specific surface areas up to 200 m2/g. The physical features of the porous polymer particles depended on the diluent type and the crosslinker content, as well as the molecular weight of polymer seed particles. By varying the molecular weight of the linear polymer, monodisperse porous polymer particles with different pore size distribution could be synthesized. Polymer seed with a low degree of crosslinking instead of linear polymer could also be used to prepare monodisperse porous polymer particles with smaller pore volume and pore size. 相似文献
18.
Electrochemical characteristics of plasticized polymer electrolytes based on poly(acrylonitrile-butadene-styrene) and poly(methyl
methacrylate) (abbreviated as ABS/PMMA) blends have been studied. The ionic conductivity of the polymer electrolyte with an
ABS/PMMA ratio of 6/4 and a plasticizer content of 60% was highest when the LiClO4 content was 4.8%. The transference numbers (T
+) of the polymer electrolytes were measured using the steady-state current method, and the T
+ values were found to be less than 0.5. The electrolyte system was found to have an electrochemical stability window up to
4.5 V. The properties of the electrode interface in contact with the polymer electrolyte were also investigated by impedance
spectroscopy, and the evolution of these spectra as a function of storage time was explained and interpreted using a solid-polymer
layer (SPL) model. The time evolution of the impedance parameters indicated that a passivation film grew rapidly on the lithium
surface immediately after assembly of the cell.
Electronic Publication 相似文献
19.
Sun Xiaoying Yang Xiaohui Liu Yunhang Wang Xinling 《Journal of polymer science. Part A, Polymer chemistry》2004,42(10):2356-2364
A multiarm star polymer was synthesized through the grafting of oligo polyglycol with urethane chain end units onto the core of hyperbranched polyglycerol (HPG), which was obtained through the cationic ring‐opening polymerization of glycidol. Samples were characterized with 13C NMR, liquid chromatography/mass spectrometry, vapor pressure osmometry, and Raman spectroscopy. The degree of branching of HPG was 0.54, and the number of arms grafting onto HPG was 4. The urethane of the arms mainly reacted with the terminal hydroxy groups of HPG. The differences between the spin–spin relaxation times indicated that the terminal segments of the star were more flexible than those of the core. Grafting polyglycol polyurethane (soft segments of polyurethane is polyglycol) onto HPG improved its dimensional stability. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2356–2364, 2004 相似文献
20.
In this project, we synthesized poly(2-isopropyl-2-oxazoline)-block- poly(dimethyl-siloxane)-block-poly(2-isopropyl-2-oxazoline) (PISOZ-PDMS-PISOZ) triblock polymer, which has been prepared as vesicles. The triblock polymer was characterized by 1H-NMR, F-NMR, LS and TEM. The size of the empty vesicle is about 60 nm. When curcumin was encapsulated into PISOZ-PDMS-PISOZ triblock polymer, formed well defined vesicles in a size about 70 nm. 相似文献