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1.
H. M. J. C. Pitawala M. A. K. L. Dissanayake V. A. Seneviratne B.-E. Mellander I. Albinson 《Journal of Solid State Electrochemistry》2008,12(7-8):783-789
A new plasticized nanocomposite polymer electrolyte based on poly (ethylene oxide) (PEO)-LiTf dispersed with ceramic filler (Al2O3) and plasticized with propylene carbonate (PC), ethylene carbonate (EC), and a mixture of EC and PC (EC+PC) have been studied for their ionic conductivity and thermal properties. The incorporation of plasticizers alone will yield polymer electrolytes with enhanced conductivity but with poor mechanical properties. However, mechanical properties can be improved by incorporating ceramic fillers to the plasticized system. Nanocomposite solid polymer electrolyte films (200–600 μm) were prepared by common solvent-casting method. In present work, we have shown the ionic conductivity can be substantially enhanced by using the combined effect of the plasticizers as well as the inert filler. It was revealed that the incorporating 15 wt.% Al2O3 filler in to PEO: LiTf polymer electrolyte significantly enhanced the ionic conductivity [σ RT (max)?=?7.8?×?10?6 S cm?1]. It was interesting to observe that the addition of PC, EC, and mixture of EC and PC to the PEO: LiTf: 15 wt.% Al2O3 CPE showed further conductivity enhancement. The conductivity enhancement with EC is higher than PC. However, mixture of plasticizer (EC+PC) showed maximum conductivity enhancement in the temperature range interest, giving the value [σ RT (max)?=?1.2?×?10?4 S cm?1]. It is suggested that the addition of PC, EC, or a mixture of EC and PC leads to a lowering of glass transition temperature and increasing the amorphous phase of PEO and the fraction of PEO-Li+ complex, corresponding to conductivity enhancement. Al2O3 filler would contribute to conductivity enhancement by transient hydrogen bonding of migrating ionic species with O–OH groups at the filler grain surface. The differential scanning calorimetry thermograms points towards the decrease of T g , crystallite melting temperature, and melting enthalpy of PEO: LiTf: Al2O3 CPE after introducing plasticizers. The reduction of crystallinity and the increase in the amorphous phase content of the electrolyte, caused by the filler, also contributes to the observed conductivity enhancement. 相似文献
2.
T. M. W. J. Bandara M. A. K. L. Dissanayake O. A. Ileperuma K. Varaprathan K. Vignarooban B.-E. Mellander 《Journal of Solid State Electrochemistry》2008,12(7-8):913-917
Solid polymer electrolyte membranes were prepared by complexing tetrapropylammoniumiodide (Pr4N+I?) salt with polyethylene oxide (PEO) plasticized with ethylene carbonate (EC), and these were used in photoelectrochemical (PEC) solar cells fabricated with the configuration glass/FTO/TiO2/dye/electrolyte/Pt/FTO/glass. The PEO/Pr4N+I?+I2?=?9:1 ratio gave the best room temperature conductivity for the electrolyte. For this composition, the plasticizer EC was added to increase the conductivity, and a further conductivity enhancement of four orders of magnitude was observed. An abrupt increase in conductivity occurs around 60–70 wt% EC; the room temperature conductivity was 5.4?×?10?7 S cm?1 for 60 wt% EC and 4.9?×?10?5 S cm?1 for the 70 wt% EC. For solar cells with electrolytes containing PEO/Pr4N+I?+I2?=?9:1 and EC, IV curves and photocurrent action spectra were obtained. The photocurrent also increased with increasing amounts of EC, up to three orders of magnitude. However, the energy conversion efficiency of this cell was rather low. 相似文献
3.
Manoj KumarS.S Sekhon 《European Polymer Journal》2002,38(7):1297-1304
The addition of plasticizer to the polyethylene oxide (PEO)-ammonium fluoride (NH4F) polymer electrolytes has been found to result in an increase in conductivity value and the magnitude of increase has been found to depend upon the dielectric constant of the plasticizer used. The addition of dimethylacetamide as a plasticizer with dielectric constant (?=37.8) higher than that of PEO (?∼5) results in an increase of conductivity by more than three orders of magnitude whereas the addition of diethylcarbonate as a plasticizer with dielectric constant (?=2.82) lower than that of PEO does not enhance the conductivity of PEO-NH4F polymer electrolytes. The increase in conductivity has further been found to depend upon the concentration of plasticizer, the concentration of salt in the polymer electrolyte as well as on the dielectric constant value of the plasticizer used. The conductivity modification with the addition of plasticizer has been explained on the basis of dissociation of ion aggregates formed in PEO-NH4F polymer electrolytes at higher salt concentrations. 相似文献
4.
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
5.
Jun Young Lee Yong Min Lee Bhaskar Bhattacharya Young-Chang Nho Jung-Ki Park 《Journal of Solid State Electrochemistry》2010,14(8):1445-1449
Solid polymer electrolytes (SPE), based on polyoctahedral silsesquioxanes (POSS) as a crosslinking agent, were prepared by radical polymerization. The ionic conductivity is greatly enhanced by introduction of crosslinkable POSS with multifunctional groups. The SPE prepared with 5 wt.% crosslinking agent shows an ionic conductivity of 5.3?×?10?4 S cm?1 at room temperature. The content of nonvolatile plasticizer, poly(ethylene glycol) dimethyl ether, in the SPE, could be raised to 95 wt.% without any leakage. The SPE is found to be electrochemically stable up to 5.3 V. Lithium polymer cell consisting of Li/SPE/LiCoO2 exhibits 80% of initial discharge capacity even at the rate of 0.1 C at room temperature after 20 cycles, which is a substantial improvement for practical consideration of lithium polymer batteries at room temperature. 相似文献
6.
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
7.
Amrtha Bhide 《European Polymer Journal》2007,43(10):4253-4270
Conduction characteristics of the poly(ethylene oxide) based new polymer electrolyte (PEO)6:NaPO3, plasticized with poly(ethylene glycol) are investigated. Free standing flexible electrolyte films of composition (PEO)6:NaPO3 + x wt.% PEG400 (30 ? x ? 70) are prepared by solution casting method. A combination of X-ray diffraction (XRD), optical microscopy and differential scanning calorimetry (DSC) studies have indicated enhancement in the amorphous phase of polymer due to the addition of plasticizer. Further, a reduction in the glass transition temperature observed from the DSC result has inferred increase in the flexibility of the polymer chains. The cationic transport number (tNa+) of 0.42 determined through combined ac-dc technique has confirmed ionic nature of conducting species. Ionic conductivity studies are carried out as a function of composition and temperature using complex impedance spectroscopy. The electrolyte with maximum PEG400 content has exhibited an enhancement in the conductivity of about two orders of magnitude compared to the host polymer electrolyte. The complex impedance data is analyzed in conductivity, permittivity and electric modulus formalism in order to throw light on transport mechanism. A solid state electrochemical cell based on the above polymer electrolyte with a configuration Na|SPE|(I2 + acetylene black + PEO) has exhibited an open circuit voltage of 2.94 V. The discharge characteristics are found to be satisfactory as a laboratory cell. 相似文献
8.
K.Kesavan Chithra M.Mathew S.Rajendran 《中国化学快报》2014,25(11):1428-1434
Poly(ethylene oxide), poly(vinyl pyrrolidone)(PEO/PVP), lithium perchlorate salt(Li Cl O4) and different plasticizer based, gel polymer electrolytes were prepared by the solvent casting technique. XRD results show that the crystallinity decreases with the addition of different plasticizers. Consequently, there is an enhancement in the amorphousity of the samples responsible for the process of ion transport. FTIR spectroscopy is used to characterize the structure of the polymer and confirms the complexation of plasticizer with host polymer matrix. The ionic conductivity has been calculated using the bulk impedance obtained through impedance spectroscopy. Among the various plasticizers, the ethylene carbonate(EC) based complex exhibits a maximum ionic conductivity value of the order of2.7279 10 4S cm 1. Thermal stability of the prepared electrolyte films shows that they can be used in batteries at elevated temperatures. PEO(72%)/PVP(8%)/Li Cl O4(8%)/EC(12%) has the maximum ionic conductivity value which is supported by the lowest optical band gap and lowest intensity in photoluminescence spectroscopy near 400–450 nm. Two and three dimensional topographic images of the sample having a maximum ionic conductivity show the presence of micropores. 相似文献
9.
Plasticizers can be used to change the mechanical and electrical properties of polymer electrolytes by reducing the degree
of crystallinity and lowering the glass transition temperature. The transport properties of gel-type ionic conducting membranes
consisting of poly(ethylene oxide) (PEO), poly(methyl methacrylate) (PMMA), LiClO4 and dioctyl phthalate, diethyl phthalate or dimethyl phthalate (DMP) are studied. The polymer films are characterized by
X-ray diffraction, Fourier transform infrared and impedance spectroscopic studies. It is found that the addition of DMP as
the plasticizer in the PEO-PMMA-LiClO4 polymer complex favours an enhancement in ionic conductivity. The maximum conductivity value obtained for the solid polymer
electrolyte film at 305 K is 3.529×10–
4 S cm–1.
Electronic Publication 相似文献
10.
High ionic conductivity P(VDF-TrFE)/PEO blended polymer electrolytes for solid electrochromic devices 总被引:1,自引:0,他引:1
Nguyen CA Xiong S Ma J Lu X Lee PS 《Physical chemistry chemical physics : PCCP》2011,13(29):13319-13326
Solid polymer electrolytes with excellent ionic conductivity (above 10(-4) S cm(-1)), which result in high optical modulation for solid electrochromic (EC) devices are presented. The combination of a polar host matrix poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE) and a solid plasticized of a low molecular weight poly(ethylene oxide) (PEO) (M(w)≤ 20,000) blended polymer electrolyte serves to enhance both the dissolution of lithium salt and the ionic transport. Calorimetric measurement shows a reduced crystallization due to a better intermixing of the polymers with small molecular weight PEO. Vibrational spectroscopy identifies the presence of free ions and ion pairs in the electrolytes with PEO of M(w)≤ 8000. The ionic dissolution is improved using PEO as a plasticizer when compared to liquid propylene carbonate, evidently shown in the transference number analysis. Ionic transport follows the Arrhenius equation with a low activation energy (0.16-0.2 eV), leading to high ionic conductivities. Solid electrochromic devices fabricated with the blended P(VDF-TrFE)/PEO electrolytes and polyaniline show good spectroelectrochemical performance in the visible (300-800 nm) and near-infrared (0.9-2.4 μm) regions with a modulation up to 60% and fast switching speed of below 20 seconds. The successful introduction of the solid polymer electrolytes with its best harnessed qualities helps to expedite the application of various electrochemical devices. 相似文献
11.
T. K. Lee S. Afiqah A. Ahmad H. M. Dahlan M. Y. A. Rahman 《Journal of Solid State Electrochemistry》2012,16(6):2251-2260
Characterizations were carried out to study on a new plasticized solid polymer electrolyte that was composed of blends of poly(vinyl chloride) (PVC), liquid 50% epoxidized natural rubber (LENR50), ethylene carbonate, and polypropylene carbonate. This freestanding solid polymer electrolyte (SPE) was successfully prepared by solution casting technique. Further analysis and characterizations were carried out by using scanning electron microscopy (SEM), X-ray diffraction, differential scanning calorimeter (DSC), Fourier transform infrared (ATR-FTIR), and impedance spectroscopy (EIS). The SEM results show that the morphologies of SPEs are compatible with good homogeneity. No agglomeration was observed. However, upon addition of salt, formation of micropores occurred. It is worth to note that micropores improve the mobility of ions in the SPE system, thus increased the ionic conductivity whereas the crystallinity analysis for SPEs indicates that the LiClO4 salt is well complexed in the plasticized PVC-LENR50 as no sharp crystallinity peak was observed for 5–15% wt. LiClO4. This implies that LiClO4 salt interacts with polymer host as more bonds are form via coordination bonding. In DSC study, it is found that the glass temperature (T g) increased with the concentration of LiClO4. The lowest T g was obtained at 41.6 °C when incorporated with 15% wt. LiClO4. The features of complexation in the electrolyte matrix were studied using ATR-FTIR at the peaks of C=O, C–O–C, and C–Cl. In EIS analysis, the highest ionic conductivity obtained was 1.20?×?10?3 S cm?1 at 15% wt. LiClO4 at 353 K. 相似文献
12.
Amartya Chakrabarti Robert Filler Braja K Mandal 《Journal of Solid State Electrochemistry》2008,12(3):269-272
Lithium rechargeable batteries featuring solvent-free highly conductive solid polymer electrolytes (SPEs) will make a dramatic
impact on the electric and hybrid-electric vehicles (EV/HEV) industry by eliminating hazards related to the use of liquid
electrolytes. In this paper, we report the synthesis and characterization of a star-shaped borate ester plasticizer, which
was then incorporated into the poly(ethylene oxide) polymer matrix in different proportions. Significant improvement was observed
in conductivity, with the best value of 9.1 × 10−5 S/cm at 30 °C. These borate ester plasticized SPEs also exhibited excellent thermal and electrochemical stabilities. 相似文献
13.
Review on gel polymer electrolytes for lithium batteries 总被引:1,自引:0,他引:1
A. Manuel Stephan 《European Polymer Journal》2006,42(1):21-42
This paper reviews the state-of-art of polymer electrolytes in view of their electrochemical and physical properties for the applications in lithium batteries. This review mainly encompasses on five polymer hosts namely poly(ethylene oxide) (PEO), poly(acrylonitrile) (PAN), poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVdF) and poly(vinylidene fluoride-hexafluoro propylene) (PVdF-HFP) as electrolytes. Also the ionic conductivity, morphology, porosity and cycling behavior of PVdF-HFP membranes prepared by phase inversion technique with different non-solvents have been presented. The cycling behavior of LiMn2O4/polymer electrolyte (PE)/Li cells is also described. 相似文献
14.
Takahiro Uno Hiroki Sano Masashi Matsumoto Masataka Kubo Takahito Itoh 《Journal of Solid State Electrochemistry》2010,14(12):2161-2167
The cross-linked composite solid polymer electrolytes composed of poly(ethylene oxide), lithium salt (LiN(SO2CF3)2), and a hyperbranched polymer whose repeating units were connected by ether-linkage (hyperbranched polymer (HBP)-2) were prepared, and their ionic conductivity, thermal properties, electrochemical stability, mechanical property, and chemical
stability were investigated in comparison with the non-cross-linked or cross-linked composite solid polymer electrolytes using
hyperbranched polymers whose repeating units were connected by ester-linkage (HBP-1a, 1b). The cross-linked composite solid polymer electrolyte using HBP-2 exhibited higher ionic conductivity than the non-cross-linked and cross-linked composite solid polymer electrolytes using
HBP-1a and HBP-1b, respectively. The structure of the hyperbranched polymer did not have a significant effect on the thermal properties and
electrochemical stability of the composite solid polymer electrolytes. The tensile strength of the cross-linked composite
solid polymer electrolyte using HBP-2 was lower than that of the cross-linked composite solid polymer electrolyte using HBP-1b, but higher than that of the non-cross-linked composite solid polymer electrolyte using HBP-1a. The HBP-2 with ether-linkage showed higher chemical stability against alkaline hydrolysis compared with HBP-1a with ester-linkage. 相似文献
15.
Kato Y. Hasumi K. Yokoyama S. Yabe T. Ikuta H. Uchimoto Y. Wakihara M. 《Journal of Thermal Analysis and Calorimetry》2002,70(3):889-896
We have focused on the poly(ethylene glycol) (PEG)-borate ester as a new type plasticizer for solid polymer electrolyte for
lithium ion secondary battery. Adding the PEG-borate ester into the electrolyte shows the increase in the ionic conductivity
of the polymer electrolyte. By measuring the glass-transition temperature of the polymer electrolytes with DSC, it is found
that the increase in ionic conductivity of the polymer electrolyte is due to the increase in ionic mobility. By investigating
the temperature dependence of the ionic conductivity of the polymer electrolytes using William-Landel-Ferry type equation,
we considered that the PEG-borate ester does not have any influence for dissociation of Li-salt.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
16.
Solid polymer electrolytes (SPEs) with high ionic conductivity and acceptable mechanical properties are of particular interest for increasing the performance of batteries. In the present work, SPEs based on poly(ethylene oxide)/poly (vinyl pyrrolidone) (PEO/PVP) with various lithium salts were prepared by solvent casting technique. The amorphous nature of the polymer-salt complex was studied by X-ray diffraction analysis. The complexation of the prepared electrolytes was confirmed by Fourier transform infrared analysis. Ionic conductivity as a function of frequency was studied at various temperatures in the range of 303–353 K. The maximum ionic conductivity value was found to be 1.08 × 10?5 S/cm for the film containing lithium bis trifluoromethane sulfonoimide (LiN[CF3SO2]2) at room temperature and the temperature dependent ionic conductivity values seem to obey Vogel-Tamman-Fulcher relation. Thermogravimetry was used to ascertain the thermal stability of the electrolytes. Photoluminescence measurements demonstrated that the sample having maximum ionic conductivity shows the minimum luminescence intensity. Ultra violet-visible analysis reveals that the values of the band gap energies were changed with the addition of various lithium salts. Porosity of the sample containing lithium bis trifluoromethane sulfonoimide (LiN[CF3SO2]2) was studied by Atomic force microscope. 相似文献
17.
Kyoung-Hee Lee Jung-Ki Park Hong-Doo Kim 《Journal of Polymer Science.Polymer Physics》1996,34(8):1427-1433
Polymer electrolytes which are adhesive, transparent, and stable to atmospheric moisture have been prepared by blending poly(methyl methacrylate)-g-poly(ethylene glycol) with poly(ethylene glycol)/LiCF3 SO3 complexes. The maximum ionic conductivities at room temperature were measured to be in the range of 10−4 to 10−5 s cm−1. The clarity of the sample was improved as the graft degree increased for all the samples studied. The graft degree of poly(methyl methacrylate)-g-poly(ethylene glycol) was found to be important for the compatibility between the poly(methyl methacrylate) segments in poly(methyl methacrylate)-g-poly(ethylene glycol) and the added poly(ethylene glycol), and consequently, for the ion conductivity of the polymer electrolyte. These properties make them promising candidates for polymer electrolytes in electrochromic devices. © 1996 John Wiley & Sons, Inc. 相似文献
18.
Dong-Won Kim Jung-Ki Park Myoung-Seon Gong 《Journal of Polymer Science.Polymer Physics》1995,33(9):1323-1331
A series of aliphatic polyesters of sebacoyl chloride and poly(ethylene glycol) containing a different number of ethylene oxide groups was synthesized and characterized. These polyesters were complexed with lithium perchlorate to obtain a new class of polymer electrolyte. The relationships between the structure and properties of these polymer electrolytes were investigated. The main factor that affects the ionic conductivity in these systems was found to be the solvating capacity of the polyester for the lithium salt. These polymer electrolytes showed ionic conductivities up to 10?5 ? 10?4 S/cm at 25°C. The mechanical strength was improved by cross-linking, and the cross-linked polyester complexed with a LiCIO4 salt showed an ionic conductivity of 2 × 10?5 S/cm at room temperature. 7Li NMR spin-spin relaxation and dielectric relaxation studies were also carried out to investigate the local environments and dynamics of ions in the polymer electrolytes. © 1995 John Wiley & Sons, Inc. 相似文献
19.
A new composition of magnesium (Mg)-ion-conducting polymer electrolyte comprising poly(ethylene oxide) (PEO) complexed with Mg trifluoromethanesulfonate (Mg triflate or Mg(Tf)2) containing different amounts of a nonionic plastic crystal succinonitrile (SN) has been prepared and characterized. High polarity and rotational disorder of the SN molecules in the plastic-crystalline phase, supports the enhancement of ionic conductivity of the PEO-Mg(Tf)2 complex system, showing a maximum room temperature ionic conductivity of ~6?×?10-4 S cm?1 observed with the addition of 50 wt.% of SN. X-ray diffraction, optical microscopy, and differential scanning calorimetry suggest a substantial structural modification, decrease in crystallinity, and various interactions in the polymer electrolyte components due to addition of SN. The cyclic voltammetry, impedance, and dc polarization studies confirm the Mg-ion conduction in the PEO complex. The electrochemical potential window of the electrolyte, observed from the linear sweep voltammetry, is determined to be ~4.1 V. The performance characteristics of the SN-incorporated polymer electrolyte system indicate their potential applicability as electrolytes in ionic devices including Mg batteries. 相似文献
20.
K. Such J. R. Stevens W. Wieczorek M. Siekierski Z. Florjanczyk 《Journal of Polymer Science.Polymer Physics》1994,32(13):2221-2233
Highly conductive solid polymeric electrolytes based upon low molecular weight poly(ethylene glycol) and ethylene oxide/propylene oxide copolymers blended with up to 50% by volume of poly(methyl methacrylate) have been synthesized using LiCF3SO3 (25:1 ether oxygen to cation ratio). Room-temperature ionic conductivities were measured to be in the range 10?4 to 10?5 S/cm for poly(methyl methacrylate) concentrations up to 30% by volume. In some cases, the addition of the poly(methyl methacrylate) enhanced the conductivity. All of the electrolytes studied were either amorphous or crystallized below 0°C. The variation of conductivity with temperature and polymer composition was measured and the results were analyzed in terms of effective medium theory and semiempirical considerations. Ionic transport is coupled to the structural relaxation of the polymer segments. At lower temperatures activated processes were required. Both charge carrier mobility and charge concentration were found to contribute to conduction. The effective medium theory quantitatively describes conductivities of amorphous heterogenous systems of limited miscibility (microphase separation) quite well. For miscible or partially crystalline systems other effects not incorporated in this theory play an important role, and conductivities are measured to be higher than theoretically predicted. © 1994 John Wiley & Sons, Inc. 相似文献