Dissertations / Theses: 'Solid Polymer Electrolyte'

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Michaels, W. C. "Microheterogeneous solid polymer electrolyte (SPE) membranes for electrocatalysis." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52934.

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Dissertation (Ph.D.)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: The deposition of platinum catalyst on cation-exchange membranes was achieved by a counter diffusion deposition method known as the Takenaka- Torikai method. The morphology of the platinum catalyst on the membranes were controlled by varying the conditions of the platinum deposition process, such as, temperature, type of reducing agent and concentration of the platinic acid solution. The effect of the sonication of platinic acid solution and the pre-treatment of membranes on the morphology of a platinum catalyst was also investigated. Platinum loading on cation-exchange membranes was determined by UV spectrophotometric and gravimetric analyses. Suitable conditions for the quantitative determination of the platinum loading on membranes by UV spectrophotometric analysis was established through the development of a protocol. Membranes were characterised using different techniques such as, Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Infrared spectrometry (IR), Dielectric analysis (DEA) and Brunauer Emmett Teller adsorption (BET). The roughness profile of a platinum catalyst embedded on a membrane was explored by various statistical methods. The statistical analysis of various data sets for a surface of a platinum-containing membrane was investigated using the Hurst exponent. The effect of surface modification of membranes on the deposition process, as well as the morphology of the platinum catalyst, was investigated. Membranes were modified with ethylene diamine (EDA) and cetyltrimethylammonium bromide surfactant. Modification of membranes with cetyltrimethylammonium bromide surfactant resulted in a unique textured platinum catalyst. The electrochemical "switching" phenomenon was investigated for EDAmodified membranes and EDA-modified membranes embedded with platinum catalyst. The "switching" phenomenon was observed in i-V cyclic curves, which were obtained by galvanodynamie measurements. The application of electro catalytic membrane systems in the anodic oxidation of water was investigated by electrochemical techniques such as galvanostatic and cyclic voltammetric measurements.
AFRIKAANSE OPSOMMING: Die deponering van 'n platinum katalis op katioon-uitruil membrane is suksesvol gedoen d.m.v. die Takenaka-Torikai metode. Die morfologie van die platinum katalis op die membrane is gekontrolleer deur variasie van die kondisies van die platinum deponeringsproses, bv. temperatuur, tipe reduseermiddel gebruik en konsentrasie van die platiensuuroplossing, asook die ultrasonifikasie van die platiensuuroplossing en voorafbehandeling van die membrane. UV spektrofotometriese asook gravimetriese analitiese metodes is gebruik om die platinumlading op katioon-uitruil membrane te bepaal. Geskikte kondisies vir die kwantitatiewe bepaling van die platinumlading op membrane d.m.v. UV spektrofotometriese analise is ontwikkel deur die skep van 'n protokol. Membrane is gekarakteriseer d.m.v. die volgende tegnieke: Atoomkrag Mikroskopie, Skanderingselektron Mikroskopie, Infrarooi Spektrometrie, di-elektriese analise en Brunauer Emmett Teller adsorpsie. Die skurtheidsprofiel van 'n platinum katalis op 'n membraan is ondersoek deur gebruik te maak van verskeie statistiese metodes. Statistiese analises van verskeie data stelsels van 'n platinum-bevattende membraan is ondersoek deur gebruik te maak van die Hurst eksponent. \ Die effek van oppervlakmodifikasie op membrane sowel as die deponeringsproses en morfologie van die platinum katalis is ondersoek deur die modifikasie van membrane met etileen diamien (EDA) en setieltrimetielammonium bromied as versepingsmiddel Die elektrochemiese omswaai van EDA-gemodifiseerde membrane sowel as gemodifiseerde platinum bevattende membrane is ondersoek d.m.v. galvanodinamiese metings. Die gebruik van elektro-katalitiese membraansisteme in die anodiese oksidasie van water is ondersoek deur gebruik te maak van elektrochemiese tegnieke, bv. galvanostatiese en sikliese voltammetriese metings.

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Kim, Jong-Chul. "Lithium deposition in solid polymer electrolyte batteries." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287985.

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Shao, Yunfan. "Highly electrochemical stable quaternary solid polymer electrolyte for all-solid-state lithium metal batteries." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1522332577785545.

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Hu, Qichao. "Electrode-Electrolyte Interfaces in Solid Polymer Lithium Batteries." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10187.

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This thesis studies the performance of solid polymer lithium batteries from room temperature to elevated temperatures using mainly electrochemical techniques, with emphasis on the bulk properties of the polymer electrolyte and the electrode-electrolyte interfaces. Its contributions include: 1) Demonstrated the relationship between polymer segmental motion and ionic conductivity indeed has a Vogel-Tammann-Fulcher (VTF) dependence, and improved the conductivity of the graft copolymer electrolyte (GCE) by almost an order of magnitude by changing the ion-conducting block from poly(oxyethylene) methacrylate (POEM) to a block with a lower glass transition temperature \((T_g)\) poly(oxyethylene) acrylate (POEA). 2) Identified the rate-limiting step in the battery occurs at the cathode-electrolyte interface using both full cell and symmetric cell electrochemical impedance spectroscopy (EIS), improved the battery rate capability by using the GCE as both the electrolyte and the cathode binder to reduce the resistance at the cathode-electrolyte interface, and used TEM and SEM to visualize the polymer-particle interface (full cells with \(LiFePO_4\) as the cathode active material and lithium metal as the anode were assembled and tested). 3) Applied the solid polymer battery to oil and gas drilling application, performed high temperature (up to 210°C) cycling (both isothermal and thermal cycling), and demonstrated for the first time, current exchange between a solid polymer electrolyte and a liquid lithium metal. Both the cell open-circuit-voltage (OCV) and the overall GCE mass remained stable up to 200°C, suggesting that the GCE is electrochemically and gravimetrically stable at high temperatures. Used full cell EIS to study the behavior of the various battery parameters as a function of cycling and temperature. 4) Identified the thermal instability of the cell was due to the reactivity of lithium metal and its passivation film at high temperatures, and used Li/GCE/Li symmetric cell EIS to study the thermal stability of the anode-electrolyte interface, which was responsible for the fast capacity fade observed at high temperatures. 5) Proposed a new electrolyte material and a new battery design called polymer ionic liquid (PIL) battery that can dramatically improve the safety, energy density, and rate capability of rechargeable lithium batteries.
Engineering and Applied Sciences

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Harry, Katherine Joann. "Lithium dendrite growth through solid polymer electrolyte membranes." Thesis, University of California, Berkeley, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10150902.

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The next generation of rechargeable batteries must have significantly improved gravimetric and volumetric energy densities while maintaining a long cycle life and a low risk of catastrophic failure. Replacing the conventional graphite anode in a lithium ion battery with lithium foil increases the theoretical energy density of the battery by more than 40%. Furthermore, there is significant interest within the scientific community on new cathode chemistries, like sulfur and air, that presume the use of a lithium metal anode to achieve theoretical energy densities as high as 5217 W˙h/kg. However, lithium metal is highly unstable toward traditional liquid electrolytes like ethylene carbonate and dimethyl carbonate. The solid electrolyte interphase that forms between lithium metal and these liquid electrolytes is brittle which causes a highly irregular current distribution at the anode, resulting in the formation of lithium metal protrusions. Ionic current concentrates at these protrusions leading to the formation of lithium dendrites that propagate through the electrolyte as the battery is charged, causing it to fail by short-circuit. The rapid release of energy during this short-circuit event can result in catastrophic cell failure.

Polymer electrolytes are promising alternatives to traditional liquid electrolytes because they form a stable, elastomeric interface with lithium metal. Additionally, polymer electrolytes are significantly less flammable than their liquid electrolyte counterparts. The prototypical polymer electrolyte is poly(ethylene oxide). Unfortunately, when lithium anodes are used with a poly(ethylene oxide) electrolyte, lithium dendrites still form and cause premature battery failure. Theoretically, an electrolyte with a shear modulus twice that of lithium metal could eliminate the formation of lithium dendrites entirely. While a shear modulus of this magnitude is difficult to achieve with polymer electrolytes, we can greatly enhance the modulus of our electrolytes by covalently bonding the rubbery poly(ethylene oxide) to a glassy polystyrene chain. The block copolymer phase separates into a lamellar morphology yielding co-continuous nanoscale domains of poly(ethylene oxide), for ionic conduction, and polystyrene, for mechanical rigidity. On the macroscale, the electrolyte membrane is a tough free-standing film, while on the nanoscale, ions are transported through the liquid-like poly(ethylene oxide) domains.

Little is known about the formation of lithium dendrites from stiff polymer electrolyte membranes given the experimental challenges associated with imaging lithium metal. The objective of this dissertation is to strengthen our understanding of the influence of the electrolyte modulus on the formation and growth of lithium dendrites from lithium metal anodes. This understanding will help us design electrolytes that have the potential to more fully suppress the formation of dendrites yielding high energy density batteries that operate safely and have a long cycle life.

Synchrotron hard X-ray microtomography was used to non-destructively image the interior of lithium-polymer-lithium symmetric cells cycled to various stages of life. These experiments showed that in the early stages of lithium dendrite development, the bulk of the dendritic structure was inside of the lithium electrode. Furthermore, impurity particles were found at the base of the lithium dendrites. The portion of the lithium dendrite protruding into the electrolyte increased as the cell approached the end of life. This imaging technique allowed for the first glimpse at the portion of lithium dendrites that resides inside of the lithium electrode.

After finding a robust technique to study the formation and growth of lithium dendrites, a series of experiments were performed to elucidate the influence of the electrolyte’s modulus on the formation of lithium dendrites. Typically, electrochemical cells using a polystyrene – block¬ – poly(ethylene oxide) copolymer electrolyte are operated at 90 °C which is above the melting point of poly(ethylene oxide) and below the glass transition temperature of polystyrene. In these experiments, the formation of dendrites in cells operated at temperatures ranging from 90 °C to 120 °C were compared. The glass transition temperature of polystyrene (107 °C) is included in this range resulting in a large change in electrolyte modulus over a relatively small temperature window. The X-ray microtomography experiments showed that as the polymer electrolyte shifted from a glassy state to a rubbery state, the portion of the lithium dendrite buried inside of the lithium metal electrode decreased. These images coupled with electrochemical characterization and rheological measurements shed light on the factors that influence dendrite growth through electrolytes with viscoelastic mechanical properties. (Abstract shortened by ProQuest.)

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Michan, Alison Louise. "Nuclear magnetic resonance characterization of solid polymer electrolyte materials." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42608.

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Solid polymer electrolytes have the potential to improve manufacturability, performance, and safety characteristics of lithium-ion batteries by replacing conventional liquid electrolytes. Two different solid polymer electrolyte materials were characterized using Nuclear Magnetic Resonance (NMR) techniques. The first material is a result of research efforts on single-ion conducting polymers. The material is intended to combine the high conductivity properties of ionic liquids with lithium cation single-ion conduction. The goal of the synthesis was to produce a polymerized ionic liquid, where crosslinking an anionic monomer (AMLi) with poly(ethylene glycol) dimethacrylate (PEGDM) immobilizes the fluorinated anionic species. Pulsed-field gradient NMR diffusion measurements of the AMLi/PEGDM samples have demonstrated that both the lithium cations and fluorinated anions are mobile and contributing toward conductivity. Therefore, further work is required to successfully immobilize the fluorinated anion in a crosslinked network. The ⁷Li and ¹⁹F diffusion coefficients of the AMLi/PEGDM 40/60 sample were 3.4x10⁻⁸ cm²/s and 2.2x10⁻⁸ cm²/s at 100°C. The second material incorporates a poly(ethylene oxide) (PEO) conductive block and polyethylene (PE) reinforcement block. The PEO/PEO-b-PE/LiClO₄ samples were not intended to be single-ion conducting and materials synthesis aimed to maximize conductivity and mechanical properties. A ⁷Li diffusion coefficient of ~4x10⁻⁸ cm²/s at 60°C was observed. It is expected that the anion would also be mobile and therefore the polymer electrolyte would be a bi-ionic conductor. These samples demonstrated higher ⁷Li diffusion coefficients at a given temperature and superior mechanical properties for a flexible polymer electrolyte compared to the AMLi/PEGDM samples. Practically, the diffusion measurements of the solid polymer samples are extremely challenging, as the spin-spin (T₂) relaxation times are very short, necessitating the development of specialized pulsed-field gradient apparatus. These results provide valuable insight into the conduction mechanisms in these materials, and will drive further optimization of solid polymer electrolytes.

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Stekly, Jan J. K. "Solid polymer electrolyte chemical concentration cells for hydrogen determination." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385363.

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Törmä, Erik. "Synthesis and characterisation of solid low-Tg polymer electrolytes for lithium-ion batteries." Thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-226754.

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Electrolytes of poly(trimethylene carbonate-co-ε-caprolactone), poly(TMC-co-CL), and LiTFSI have been prepared and characterised. The copolymers were analysed with GPC and NMR, which showed that random high molecular weight copolymers of desired compositions had been obtained. The electrolytes with varied salt concentration were examined with TGA, DSC, FTIR and impedance spectroscopy. The highest ionic conductivities were measured for the copolymer of 60:40 ratio of TMC:CL and for the homopolymer poly(ε-caprolactone), PCL, both electrolytes with 28 wt% LiTFSI. The ionic conductivity was measured to of the order of 10−3 S cm−1 for the PCL electrolyte and 10−4 S cm−1 for the 60:40 copolymer at 50 °C.

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Yang, Run. "A Superionic Conductive Solid Polymer Electrolyte Based Solid Sodium Metal Batteries with Stable Cycling Performance at Room Temperature." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1619741453185762.

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Davies, Damian Patrick. "Development and optimisation of solid polymer electrolyte fuel cell systems." Thesis, De Montfort University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391234.

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Ren, tianli ren. "FABRICATION AND EVALUATION ON ELECTROCHEMICAL PERFORMANCE OF SOLID POLYMER ELECTROLYTE MEMBREANE FOR LITHIUM-ION BATTERY." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1495712448807722.

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Zhang, Yuhan. "POLYMER ELECTROLYTES FOR HIGH CURRENT DENSITY LITHIUM STRIPPING/PLATING TEST." University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1555090752890092.

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Leahy, Scott B. "Active Flow Control of Lab-Scale Solid Polymer Electrolyte Fuel Cells." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5188.

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The effects of actively pulsing reactant flow rates into solid polymer electrolyte fuel cells were investigated in this thesis. First, work was conducted to determine the magnitude of voltage response to pulsed reactant flow on a direct hydrogen proton exchange membrane (PEM) cell. The effects of pulsed reactant flow into a direct methanol fuel cell (DMFC) were then considered. The PEM work showed substantially greater response to pulsed air flow than to pulsed fuel flow. It was found that several parameters affect the magnitude of cell response to active flow control (AFC). Increasing current load, increasing the magnitude of flow oscillation, decreasing the frequency of oscillation, and decreasing the average level of excess reactant supplied were found to maximize both the level of voltage oscillations and the decrease in cell power from steady state performance. Greater response to pulsed oxidant flow is believed to have been observed due to effects brought about by changes in membrane humidity. In contrast, pulsed fuel flow showed the greatest response in the study of DMFC technology. In this case, time averaged cell voltage was found to increase as the time averaged fuel flow rate was reduced. The increase in average cell power is the result of a reduction in methanol crossover; sustainable increases of up to 6% in power output were measured. The parameters found to effect the increase in cell power observed include the frequency of oscillation and the time-averaged NOSfuel. Pulsed air flow on the DMFC did not show any such rise in voltage, supporting the hypothesis that a reduction in methanol crossover is the phenomenon which brings about enhanced performance.

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Peng, Wei. "Development of a solid polymer electrolyte sensor for transcutaneous oxygen monitoring." Case Western Reserve University School of Graduate Studies / OhioLINK, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=case1056745410.

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Li, Si. "HIGHLY CONDUCTIVE SOLID POLYMER ELECTROLYTE CONTAINING LiBOB AT ROOM TEMPERATURE FOR ALL SOLID STATE BATTERY." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1490481514905008.

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Zhao, Fangtong. "A SOLID-STATE COMPOSITE ELECTROLYTE FOR LITHIUM-ION BATTERIES WITH 3D-PRINTING FABRICATION." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1619814091802231.

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Yin, Yijing. "An Experimental Study on PEO Polymer Electrolyte Based All-Solid-State Supercapacitor." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/440.

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Supercapacitors are one of the most important electrochemical energy storage and conversion devices, however low ionic conductivity of solid state polymer electrolytes and the poor accessibility of the ions to the active sites in the porous electrode will cause low performance for all-solid-state supercapacitors and will limit their application. The objective of the dissertation is to improve the performance of all-solid-state supercapactor by improving electrolyte conductivity and solving accessibility problem of the ions to the active sites. The low ionic conductivity (10-8 S/cm) of poly(ethylene oxide) (PEO) limits its application as an electrolyte. Since PEO is a semicrystal polymer and the ion conduction take place mainly in the amorphous regions of the PEO/Lithium salt complex, improvements in the percentage of amorphous phase in PEO or increasing the charge carrier concentration and mobility could increase the ionic conductivity of PEO electrolyte. Hot pressing along with the additions of different lithium salts, inorganic fillers and plasticizers were applied to improve the ionic conductivity of PEO polymer electrolytes. Four electrode methods were used to evaluate the conductivity of PEO based polymer electrolytes. Results show that adding certain lithium salts, inorganic fillers, and plasticizers could improve the ionic conductivity of PEO electrolytes up 10-4 S/cm. Further hot pressing treatment could improve the ionic conductivity of PEO electrolytes up to 10-3 S/cm. The conductivity improvement after hot pressing treatment is elucidated as that the spherulite crystal phase is convert into the fringed micelle crystal phase or the amorphous phase of PEO electrolytes. PEO electrolytes were added into active carbon as a binder and an ion conductor, so as to provide electrodes with not only ion conduction, but also the accessibility of ion to the active sites of electrodes. The NaI/I2 mediator was added to improve the conductivity of PEO electrolyte and provide pseudocapacitance for all-solid-state supercapacitors. Impedance, cyclic voltammetry, and gavalnostatic charge/discharge measurements were conducted to evaluate the electrochemical performance of PEO polymer electrolytes based all-solid-state supercapacitors. Results demonstrate that the conductivity of PEO electrolyte could be improved to 0.1 S/cm with a mediator concentration of 50wt%. A high conductivity in the PEO electrolyte with mediator is an indication of a high electron exchange rate between the mediator and mediator. The high electron exchange rates at mediator carbon interface and between mediator and mediator are essential in order to obtain a high response rate and high power. This automatically solves the accessibility problem. With the addition of NaI/I2 mediator, the specific capacitance increased more than 30 folds, specific power increased almost 20 folds, and specific energy increased around 10 folds. Further addition of filler to the electrodes along with the mediator could double the specific capacitor and specific power of the all-solid-state supercapacitor. The stability of the corresponded supercapacitor is good within 2000 cycles.

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Girt, Robert Stephen. "Scale-up of the solid polymer electrolyte reactor for electro-organic synthesis." Thesis, University of Newcastle upon Tyne, 1997. http://hdl.handle.net/10443/3611.

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Electro-organic reactions are often complicated by the need to add supporting electrolytes and co-solvents. In many cases these additives take part in side reactions causing low yields and hinder the purification stages. The solid polymer electrolyte (SPE) reactor uses an ion exchange membrane to transfer charged species between the electrodes and so eliminates the need for any additives. In this way improvements in electrochemical processing can be achieved. The SPE reactor has only been studied for model organic and aqueous based electrochemical reactions. The aims of this project were to develop the reactor for use as a suitable means of synthesising alcohols and acids based on substituted toluenes. This involved selection of suitable electrode material, polymer electrolyte pre-treatment and reactor modelling. According to published reports the direct electro-oxidation of toluene takes place with maximum yields of 19% with an acetic acid co-solvent and a nitric acid supporting electrolyte. Higher yields are possible with inorganic mediators such as Mn³⁺ and Cr⁶⁺. 30% yields of methoxylated products are possible from electrolysis in methanol although many non volatile by-products are formed. Initial research was spent investigating the oxidation of toluene in sulphuric acid at a lead dioxide rotating disk electrode. It was found that the reaction is mass transfer limited in the potential region below gas evolution. The order of reaction with respect to toluene was 0.5. Electrolysis of toluene on platinum mesh in nitric acid with and without acetic acid was found to produce benzyl alcohol and benzaldehyde with low current efficiencies. Without co-solvent the maximum current efficiency was 10% at 2S0Alm². An SPE reactor fabricated from glass with an active electrode area of Scm2 was used to perform electrode tests. Highest yields of benzaldehyde were obtained using nickel foam, graphite felt and palladium coated mesh electrodes. The current efficiencies were 52.4%, 20.3% and 10.7% respectively. This work highlighted the need for a good membrane-electrode contact. The oxidation of benzyl alcohol in the same reactor using nickel foam Abstract was accomplished with a current efficiency of 85.4% showing that the difficult step in the oxidation of toluene was the first one to benzyl alcohol. Pre-treatment of the membrane by swelling in solvents was considered to be an important factor in the performance of the SPE reactor. Several ion exchange membranes were pre-treated in a variety of aqueous and organic solvents including methanol, toluene, DMF, water and sulphuric acid. Nafion® 117 was found to increase in size more than the other tested membranes in all solvents except water and sulphuric acid. Many of the pre-treated membranes were tested in an SPE reactor made from steel with an active electrode area of 2lcm2 for the oxidation of toluene in methanol. The anode-membrane potential was measured as a function of time and current density with Nafion® 117 having the lowest values of potential. Selection of the pre-treatment method for future use was determined by assessing the performance in the reactor, contamination of products and chemical hazards. Swelling in aqueous solvents was the chosen procedure. The steel SPE reactor was operated in continuous mode with recycle for the oxidation of toluene in methanol. Galvanostatic electrolysis took place at several current densities, temperatures and feed concentrations. Two products were identified as ⍺-methoxytoluene and ⍺,⍺-dimethoxytoluene and these were formed at low current efficiencies between 1.4% and 9%. The main product was thought to be an oligomer of toluene. The gas generated was found to be mainly hydrogen with a small amount of oxygen thought to come from residual water in the pre-treated membrane. A computer simulation of the SPE reactor for toluene oxidation in methanol was based on two series and one parallel reaction. These were first order in reactant species and followed Tafel type kinetics. Mass transfer of dilute reactants was based on Fickian diffusion. Parameters not available in the literature such as membrane potential and electro-osmotic flow were correlated to applied variables using experimental data and multiple linear regression. The importance of electro-osmotic flow in the SPE reactor was demonstrated by considering its effect on product distribution. The model showed that the oligomerisation of toluene was the dominant reaction making the SPE reactor unsuitable for the oxidation of toluene.

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Sun, Bing. "Functional Polymer Electrolytes for Multidimensional All-Solid-State Lithium Batteries." Doctoral thesis, Uppsala universitet, Strukturkemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-248084.

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Pressing demands for high power and high energy densities in novel electrical energy storage units have caused reconsiderations regarding both the choice of battery chemistry and design. Practical concerns originating in the conventional use of flammable liquid electrolytes have renewed the interests of using solvent-free polymer electrolytes (SPEs) as solid ionic conductors for safer batteries. In this thesis work, SPEs developed from two polymer host structures, polyethers and polycarbonates, have been investigated for all-solid-state Li- and Li-ion battery applications. In the first part, functional polyether-based polymer electrolytes, such as poly(propylene glycol) triamine based oligomer and poly(propylene oxide)-based acrylates, were investigated for 3D-microbattery applications. The amine end-groups were favorable for forming conformal electrolyte coatings onto 3D electrodes via self-assembly. In-situ polymerization methods such as UV-initiated and electro-initiated polymerization techniques also showed potential to deposit uniform and conformal polymer coatings with thicknesses down to nano-dimensions. Moreover, poly(trimethylene carbonate) (PTMC), an alternative to the commonly investigated polyether host materials, was synthesized for SPE applications and showed promising functionality as battery electrolyte. High-molecular-weight PTMC was first applied in LiFePO4-based batteries. By incorporating an oligomeric PTMC as an interfacial mediator, enhanced surface contacts at the electrode/SPE interfaces and obvious improvements in initial capacities were realized. In addition, room-temperature functionality of PTMC-based SPEs was explored through copolymerization of ε-caprolactone (CL) with TMC. Stable cycling performance at ambient temperatures was confirmed in P(TMC/CL)-based LiFePO4 half cells (e.g., around 80 and 150 mAh g-1 at 22 °C and 40 °C under C/20 rate, respectively). Through functionalization, hydroxyl-capped PTMC demonstrated good surface adhesion to metal oxides and was applied on non-planar electrodes. Ionic transport behavior in polycarbonate-SPEs was examined by both experimental and computational approaches. A coupling of Li ion transport with the polymer chain motions was demonstrated. The final part of this work has been focused on exploring the key characteristics of the electrode/SPE interfacial chemistry using PEO and PTMC host materials, respectively. X-ray photoelectron spectroscopy (XPS) was used to get insights on the compositions of the interphase layers in both graphite and LiFePO4 half cells.

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Chaplin, Richard Paul Spencer. "The reduction of carbon dioxide to formate in a solid polymer electrolyte reactor." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341196.

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Fu, Guopeng. "INVESTIGATION ON THE STRUCTURE-PROPERTY RELATIONSHIPS IN HIGHLY ION-CONDUCTIVE POLYMER ELECTROLYTE MEMBRANES FOR ALL-SOLID-STATE LITHIUM ION BATTERIES." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1508508844968127.

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Williams, Mario. "Characterization of platinum-group metal nanophase electrocatalysts employed in the direct methanol fuel cell and solid-polymer electrolyte electrolyser." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&amp.

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Rendon, Piedrahita Camilo. "Study of highly conductive, flexible polymer electrolyte membranes and their novel flexoelectric effect." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1541440496157425.

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LINGUA, GABRIELE. "Newly designed single-ion conducting polymer electrolytes enabling advanced Li-metal solid-state batteries." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2969103.

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Cao, Jinwei. "Phase Diagram Approach to Control of Ionic Conductivity and Electrochemical Stability of Solid Polymer Electrolyte Membrane for Li-ion Battery Application." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1398789082.

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Li, Winton. "Hydrogen peroxide electrosynthesis in solid polymer electrolyte (spe) reactors with and without power co-generation." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62136.

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For applications that require small amounts of H₂O₂ or have economically difficult transportation means, an alternate, on-site H₂O₂ production method to the current industrial anthraquinone auto-oxidation process is needed. Thus far neutral production of H₂O₂ has been limited to bench-top laboratory scaled research with low yield of H₂O₂ [1]. To produce neutral H₂O₂ on-site and on-demand for drinking water purification, the electroreduction of oxygen at the cathode of a solid polymer electrolyte (SPE) cell could be a possible solution. The work presented here has utilized a SPE cell operating in either fuel cell mode (power generating) or electrolysis mode (power consuming) to produce H₂O₂. The SPE cell reactor is operated with a continuous flow of cathode carrier water flowing through the cathode to remove the product H₂O₂. Two catalysts were chosen for further study in this work, one is the inorganic cobalt-carbon composite catalyst, to be used in both fuel cell mode and electrolysis mode operation. The other is the riboflavin-anthraquinone-carbon composite catalyst, to be used in only the electrolysis mode operation. Through parametric experiments in both modes of operation, the Co-C catalyst was able to achieve peroxide production rate of ~200 μmol hr-¹ cm-² and 4 mW cm-² operating at a cell temperature of 60°C with a current density of 30 mA cm-² and 30% current efficiency in fuel cell mode operation. Long term recycle experiments over a period of 72 hours showed an accumulated H2O2 concentration of over 1400 ppm. Investigation of both catalysts in electrolysis mode operation showed that the AQ-C catalyst achieved maximum H₂O₂ production of 580 μmol hr-¹ cm-² operating at 40°C and a current density of 240 mA cm-² with an 8% current efficiency; while the Co-C catalyst had a maximum H₂O₂ production rate of 360 μmol hr-¹ cm-² operated at 240 mA cm-² with 8% current efficiency. Long term recycle study of both catalysts in electrolysis mode generated maximum H₂O₂ concentrations of over 3000 ppm in 72 hours. Water sample analysis showed no degradation of the catalysts in either mode of operation.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate

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27

Heyl, Anna [Verfasser]. "Elektrochemische Entchlorung von Schadstoffen im Abwasser mit Hilfe der Solid-Polymer-Electrolyte-Technologie / Anna Heyl." Aachen : Shaker, 2006. http://d-nb.info/1186585838/34.

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Ek, Gustav. "A study of poly(vinyl alcohol) as a solid polymer electrolyte for lithium-ion batteries." Thesis, Uppsala universitet, Strukturkemi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-319268.

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The use of solid polymer electrolytes in lithium-ion batteries has the advantage in terms of safety and processability, however they often lack in terms of performance. This is of major concern in applications where high current densities or rapidly changing currents are important. Such applications include electrical vehicles and energy storage of the electrical grid to accommodate fluctuations when using renewable energy sources such as wind and solar. In this study, the use of commercial poly(vinyl alcohol) (PVA) as a solid polymer electrolyte for use in lithium-ion batteries has been evaluated. Films were prepared using various lithium salts such as lithium bis(trifluoromethane)sulfonimide (LiTFSI) and casting techniques. Solvent free films were produced by substituting the solvent Dimethyl sulfoxide (DMSO) with water and rigouros drying or by employing a hot-pressing technique. The best performing system studied was PVA-LiTFSI-DMSO, which reached ionic conductivities of 4.5E-5 S/cm at room temperature and 0.45 mS/cm at 60 °C. The solvent free films showed a drop of ionic conductivity by roughly one order of magnitude compared to films with residual DMSO present. High ionic conductivities in PVA-LiTFSI-DMSO electrolytes are thus ascribed to fast lithium ion transport through the liquid domain of DMSO, or by plasticizing effects of salt and solvent on the polymer. Thermal analysis of the films showed a clear plasticizing effect of DMSO by a decrease in the glass transition temperature. FTIR analysis showed complexation of all the lithium salts investigated with the OH-groups of the polymer by a shift in the characteristic frequencies of both salts and polymer. For the first time, prototype battery cells containing PVA electrolytes were manufactured and evaluated by galvanostatic cycling. PVA-LiTFSI-DMSO showed stable cycling performance for 15 cycles. Solvent free electrolytes were also investigated but did not result in any stable cycling performance.

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29

Chen, PoYun. "Role of Ionic Liquid in Electroactive Polymer Electrolyte Membrane for Energy Harvesting and Storage." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1590688110146547.

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30

He, Ruixuan. "Studies on Ionic Conductivity and Electrochemical Stability of Plasticized Photopolymerized Polymer Electrolyte Membranes for Solid State Lithium Ion Batteries." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1478969519588062.

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Wiemhöfer, Hans-Dieter. "Lithium Ion Transport in Polymer Electrolyte Films for Solid State Batteries – An Overview on Concepts, Techniques and Results." Diffusion fundamentals 21 (2014) 7, S.1, 2014. https://ul.qucosa.de/id/qucosa%3A32399.

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Yahata, Yoshikazu. "Extended Design of Concentrated-Polymer-Brush-Decorated Hybrid Nanoparticles and Their Use for Phase-Separation Control." Kyoto University, 2018. http://hdl.handle.net/2433/232486.

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Ravet, Nathalie. "Développement et caractérisations de constituants d'un système électrochrome tout solide : photo-électrochimie aux interfaces WO3/électrolyte polymère." Grenoble INPG, 1994. http://www.theses.fr/1994INPG0150.

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Ce travail s'inscrit dans le cadre du contrat europeen brite euram nomme fredops visant a l'elaboration de fenetres electrochromes tout solide, a reponse rapide, sur substrat plastique. Ces fenetres sont des systemes protoniques, nous les avons etudies sous deux aspects. D'une part, nous avons modifie par reticulation ionique une famille deja connue d'electrolytes polymeres anhydres a conduction protonique obtenus par dissolution d'acide orthophosphorique dans un polymere, la polyethylenimine branchee (bpei), dans le but principalement d'en ameliorer les proprietes mecaniques. Ces nouveaux electrolytes ont ete caracterises en termes de proprietes optiques, de stabilite thermique et electrochimique, de conductivite et de tenue mecanique. Cette etude a permis de definir la composition de l'electrolyte repondant au mieux au cahier des charges du projet fredops. Par ailleurs, une etude du mecanisme de conduction ionique est presentee, et une nouvelle approche proposee. D'autre part, nous presentons une etude originale par photo-electrochimie de l'interface entre un materiau electrochrome wo3 et un de nos electrolytes polymeres, de plusieurs echantillons de wo3 realises par pulverisation cathodique sur un substrat de plastique souple recouvert d'ito. Nous montrons que la mesure et l'exploitation de la reponse photo-electrochimique en lumiere monochromtique de ce type d'interface sont possibles. Les photo-caracteristiques en potentiel sont examinees notamment sous l'angle de la relation possible entre proprietes semi-conductrices et electrochromiques de wo3. L'etude des photo-caracteristiques en longueur d'onde a revele une modification de l'ito induite par le depot de wo3, prejudiciable au bon fonctionnement des systemes electrochromes

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Fan, Jui Chin. "The Impact of Nanostructured Templates and Additives on the Performance of Si Electrodes and Solid Polymer Electrolytes for Advanced Battery Applications." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7568.

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The primary objectives of this research are: (1) use a hierarchical structure to study electrode materials for next-generation lithium-ion batteries (LIBs) and (2) understand the fundamentals and utility of solid polymer electrolytes (SPEs) with the addition of halloysite nanotubes (HNTs) for battery applications. Understanding the fundamental principles of electrode and electrolyte materials allows for the development of high-performance LIBs. The contributions of this dissertation are described below. Encapsulated Si-VACNT Electrodes. Two hurdles prevent Si-based electrodes from mass production. First, bulk Si undergoes volume expansion up to 300%. Second, a solid-electrolyte interphase (SEI) forms between the interface of the electrolyte and electrode, which consumes battery capacity and creates more resistance at the interface. Si volume changes were overcome by depositing silicon on vertically-aligned carbon nanotubes (VACNTs). Encapsulating the entire Si-VACNT electrode surface with carbon was used to mitigate SEI formation. Although SEI formation was reduced by the encapsulation layer, capacity fade was still observed for encapsulated electrodes, indicating that SEI formation was not the primary factor affecting capacity fade. Additionally, the impact of the encapsulation layer on Li transport was examined. Two different transport directions and length scales were relevant””(1) radial transport of Li in/out of each Si-coated nanotube (~40 nm diameter) and (2) Li transport along the length of the nanotubes (~10 µm height). Experimental results indicated that the height of the Si-VACNT electrodes did not limit Li transport, even though that height was orders of magnitude greater than the diameter of the tubes. Simulation and experimental data indicated that time constant for Li diffusion into silicon was slow, even though the diffusion distance was short relative to the tube height. Other factors such as diffusion-induced stress likely had a significant impact on diffusion through the thin silicon layer. Solid Polymer Electrolytes. A thorough understanding of the relationships between physical, transport, and electrochemical properties was studied. HNT addition to polyethylene oxide (PEO) electrolytes not only improved the physical properties, such as reduction of the crystallinity of PEO, but also enhanced transport properties like the salt diffusivity. The processing steps were important for achieving enhanced properties. Moreover, HNTs were found to stabilize the interfacial properties of the SPE films during cycling. Specifically, HNT-containing SPE films were successfully cycled at room temperature, which may have important implications for SPE-based batteries.

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Raut, Prasad S. "Towards Development Of Polymeric Compounds For Energy Storage Devices And For Low Energy Loss Tires." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1493947416353888.

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Gle, David. "Synthèse de copolymères à architectures complexes à base de POE utilisés en tant qu'électrolytes polymères solides pour une application dans les batteries lithium métal-polymère." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4761/document.

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Dans le contexte d'un développement durable, les véhicules électriques apparaissent comme une solution incontournable dans le futur. Parmi les dernières évolutions sur les batteries, les systèmes constitués d'une électrode au lithium (technologie lithium métal) présente des performances remarquables en termes de densité d'énergie. L'inconvénient majeur de cette méthodologie est lié à la formation de dendrites lors de la recharge susceptibles d'occasionner des courts-circuits conduisant à l'explosion de la batterie. C'est dans cet axe que s'inscrit mon sujet de thèse dont l'objectif est de développer un électrolyte polymère solide présentant une conductivité ionique élevée (2.10-4 S.cm-1 à40°C) et une tenue mécanique suffisante (30 MPa) pour limiter les phénomènes de croissance dendritique. Pour cela, la polymérisation contrôlée par les nitroxydes (NMP) a été utilisée pour synthétiser des copolymères à blocs avec un bloc possédant des groupes d'oxyde d'éthylène –CH2-CH2-O- permettant la conduction des ions lithium et un bloc de polystyrène assurant la tenue mécanique de l'électrolyte final. Le bloc assurant la conduction ionique des architectures ainsi synthétisées sont constituées soit de POE sous forme linéaire soit de POE sous forme de peigne
In the context of sustainable development, electric vehicles appear to be a major solution for the future. Among the lastest technologies, the Lithium Metal Polymer battery has presented very interesting performances in terms of energy density. The main drawback of this system is the formation of lithium dendrites during the refill of the battery that could cause short circuits leading to the explosion of the battery. The aim of my PhD is to develop a Solid Polymer Electrolyte showing a high ionic conductivity (2.10-4 S.cm-1 at 40°C) and a high mechanical strength (30 MPa) to prevent dendritic growth. For that purpose, Nitroxide Mediated Polymerization is used to synthesize block copolymers with a PEO moiety for ionic conduction –CH2-CH2-O- and polystyrene for mechanical strength. Different kind of architectures have been synthesized : block copolymer with linear PEO moiety or with grafted PEO moiety

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37

Gle, David. "Synthèse de copolymères à architectures complexes à base de POE utilisés en tant qu'électrolytes polymères solides pour une application dans les batteries lithium métal-polymère." Electronic Thesis or Diss., Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4761.

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Dans le contexte d'un développement durable, les véhicules électriques apparaissent comme une solution incontournable dans le futur. Parmi les dernières évolutions sur les batteries, les systèmes constitués d'une électrode au lithium (technologie lithium métal) présente des performances remarquables en termes de densité d'énergie. L'inconvénient majeur de cette méthodologie est lié à la formation de dendrites lors de la recharge susceptibles d'occasionner des courts-circuits conduisant à l'explosion de la batterie. C'est dans cet axe que s'inscrit mon sujet de thèse dont l'objectif est de développer un électrolyte polymère solide présentant une conductivité ionique élevée (2.10-4 S.cm-1 à40°C) et une tenue mécanique suffisante (30 MPa) pour limiter les phénomènes de croissance dendritique. Pour cela, la polymérisation contrôlée par les nitroxydes (NMP) a été utilisée pour synthétiser des copolymères à blocs avec un bloc possédant des groupes d'oxyde d'éthylène –CH2-CH2-O- permettant la conduction des ions lithium et un bloc de polystyrène assurant la tenue mécanique de l'électrolyte final. Le bloc assurant la conduction ionique des architectures ainsi synthétisées sont constituées soit de POE sous forme linéaire soit de POE sous forme de peigne
In the context of sustainable development, electric vehicles appear to be a major solution for the future. Among the lastest technologies, the Lithium Metal Polymer battery has presented very interesting performances in terms of energy density. The main drawback of this system is the formation of lithium dendrites during the refill of the battery that could cause short circuits leading to the explosion of the battery. The aim of my PhD is to develop a Solid Polymer Electrolyte showing a high ionic conductivity (2.10-4 S.cm-1 at 40°C) and a high mechanical strength (30 MPa) to prevent dendritic growth. For that purpose, Nitroxide Mediated Polymerization is used to synthesize block copolymers with a PEO moiety for ionic conduction –CH2-CH2-O- and polystyrene for mechanical strength. Different kind of architectures have been synthesized : block copolymer with linear PEO moiety or with grafted PEO moiety

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38

Coutterez, Claire. "Synthèse, caractérisation et étude des propriétés d'oligomères et polymères hétéroarylène vinylènes." Grenoble INPG, 1998. http://www.theses.fr/1998INPG0163.

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Le travail de cette these a concerne la synthese, la caracterisation et l'etude de proprietes d'usage de structures oligomeres et polymeres conjuguees. L'originalite de ces travaux reside d'une part dans l'utilisation d'heterocycles furaniques et thiopheniques comme elements constitutifs des chaines et d'autre part, dans le fait que de nombreux composes oligomeres ont ete cibles, isoles et caracterises. Les possibilites d'application de ces materiaux dans les domaines touchant a l'electronique (conducteurs ou semi-conducteurs), a l'optique (cristaux liquides) et a la luminescence photo- et electroinduite, ont ete ensuite explorees. Ces recherches se divisent en cinq themes : (i) etude des reactions de polycondensation en milieu basique du 5-methyl furfural et du 5-2-(5-methyl furyl vinylene)furfural, avec caracterisation precise des oligo(furylene vinylene)s resultants et des polymeres correspondants. Etude des proprietes de conduction electronique apres dopage a l'iode. Etude de la photoluminescence. (ii) synthese et caracterisation d'oligo(heteroarylene vinylene)s furaniques, thiopheniques et mixtes par condensation en milieu basique de monomeres furaniques et/ou thiopheniques. (iii) synthese et caracterisation de bases de schiff ene-heterocycliques/aromatiques mono- et difonctionnelles. Etudes des proprietes thermiques et plus particulierement du comportement mesogene de ces structures. (iv) preparation d'electrolytes polymeres reticules (macrobases de schiff) : formation photochimique du reseau via la presence intrinseque d'unites -2,5-fu-ch = ch-fu-2,5-chromophores. Etude de la conductivite ionique apres dopage avec des sels de lithium. (v) preparation de polyacetylenes monosubstitues par des esters 2-furoiques dans le but d'obtenir des materiaux solubles et possedant, sous forme de membrane des proprietes de permeabilite selective des fluides.

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39

Castro, J?nior Jos? Geraldo Mendes. "Estudo de eletrodegrada??o de poluentes emergentes em c?lulas eletroqu?micas do tipo eletr?lito polim?rico s?lido." UFVJM, 2017. http://acervo.ufvjm.edu.br/jspui/handle/1/1589.

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Eletrodos de di?xido de chumbo (PbO2) suportados sobre tecido de carbono e tela de a?o inoxid?vel foram utilizados na degrada??o eletroqu?mica dos f?rmacos paracetamol (PCT) e dipirona (DPN), utilizando-se uma c?lula eletroqu?mica do tipo eletr?lito polim?rico s?lido (EPS) munida de eletrodos perme?veis a fluidos (EPFs). Todos os estudos foram conduzidos na condi??o de batelada empregando-se a ?gua livre de eletr?litos. Os estudos eletroqu?micos de degrada??o dos f?rmacos foram conduzidos em fun??o da densidade de corrente aparente (jap) (ex., 5, 10, 20, 100, 150 e 200 mA cm-2) e da concentra??o inicial (ex., 10, 30 e 50 mg L 1). As amostras tratadas foram analisadas pelas t?cnicas de espectrofotometria na regi?o do UVVis, cromatografia l?quida de alta efici?ncia (CLAE) e demanda qu?mica de oxig?nio (DQO). Verificou-se para os diferentes casos envolvendo as baixas densidades de corrente que a remo??o das bandas de absor??o no UV-Vis, a remo??o da concentra??o dos f?rmacos (CLAE) e a redu??o da DQO (grau de mineraliza??o) n?o foram significativos. Contrariamente, no caso das elevadas densidades de corrente evidenciou-se uma significante melhora na degrada??o dos f?rmacos em decorr?ncia da atua??o do oz?nio gerado eletroquimicamente. Os melhores resultados foram obtidos para baixas concentra??es dos f?rmacos. Redu??es superiores a 95 % de DQO para o PCT e superiores a 75 % para a DPN foram obtidas. Eletrodos de PbO2 dopados com n?quel (ex., Ni-PbO2) suportados sobre tecido de carbono e tela de a?o inoxid?vel foram confeccionados e caracterizados. A an?lise de microscopia eletr?nica de varredura (MEV) revelou o aparecimento de defeitos superficiais, com a varia??o da concentra??o nominal do Ni no banho eletrol?tico utilizado no preparo do eletrodo por eletrodeposi??o. An?lises de difratometria de raios-X (DRX) corroboraram os resultados de MEV revelando, em alguns casos, picos mais alargados e de menor intensidade (ex., redu??o no tamanho m?dio dos cristalitos) com a varia??o da concentra??o nominal do Ni, indicando assim uma interfer?ncia no processo de eletrodeposi??o do PbO2. Curvas de polariza??o em condi??es quaseestacion?rias foram obtidas para o processo eletr?dico da rea??o de desprendimento de oxig?nio (RDO) sendo verificado que n?o houve influ?ncia significativa do dopante sobre esta rea??o, a qual ocorre em paralelo ao processo de degrada??o oxidativa dos f?rmacos. Verificou-se que a produ??o de oz?nio foi ligeiramente favorecida em algumas concentra??es do dopante e em altas densidades de corrente. No entanto, n?o foi verificada influ?ncia significativa sobre o grau de mineraliza??o dos f?rmacos PCT e DPN mediante uso de eletrodos dopados com Ni.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017.
Lead dioxide (PbO2) electrodes supported on carbon cloth and stainless-steel mesh substrates were used in the electrochemical degradation of the drugs paracetamol (PCT) and dipyrone (DPN), using a solid polymer electrolyte electrochemical cell (SPE) having fluid-permeable electrodes (FPEs). All studies were conducted in batch condition using the electrolyte-free water. The electrochemical degradation of the drugs was accomplished as a function of the apparent current density (ex., 5, 10, 20, 100, 150 and 200 mA cm-2) and the initial concentration (ex., 10, 30 and 50 mg L-1). The treated samples were analyzed using the UV-Vis spectrophotometry technique, the high-performance liquid chromatography (HPLC), as well as the chemical oxygen demand (COD). For the different cases involving the application of low current density values, it was not verified significant changes accounting for the removal of the UV-Vis absorption band, the drug concentration (HPLC), and the COD decrease (ex., the degree of mineralization). In contrast, in the case of high current densities, a significant improvement in the degradation of the drugs was evidenced as a result of the influence of the electrochemically generated ozone. The best findings were obtained for low drug concentrations. Reductions of above 95% COD for PCT and above 75% for DPN were obtained. Nickel-doped PbO2 electrodes (ex., Ni-PbO2) supported on carbon cloth and stainlesssteel mesh were fabricated and characterized. Scanning electron microscopy (SEM) revealed the appearance of surface defects with a reduction in crystal size with the different Ni concentration in the electrolytic bath used to prepare the electrode by electrodeposition. X-ray diffraction (XRD) analyzes corroborated with the SEM results revealing the formation of broader peaks with lower intensity, in some cases, (ex., reduction in the average crystallite size) with the variation of the nominal dopant concentration in the electrolytic bath, thus indicating an interference in the electrodeposition process for PbO2. Quasi-stationary polarization curves were obtained for the electrode process of the oxygen evolution reaction (OER) and it was verified that there was no significant influence of the dopant on this reaction, which occurs in parallel to the process comprising the oxidative degradation of the drugs. It was found that the ozone generation was slightly favored in some concentrations of the dopant and in higher current densities. However, no significant influence was verified on the degree of mineralization of PCT and DPN by the use of Ni-PbO2 electrodes.

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40

Gerbaux, Luc. "Modélisation d'une pile à combustible de type hydrogène/air et validation expérimentale." Grenoble INPG, 1996. http://www.theses.fr/1996INPG0163.

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Petrik, Leslie F. "Pt Nanophase supported catalysts and electrode systems for water electrolysis." Thesis, University of the Western Cape, 2008. http://hdl.handle.net/11394/2743.

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Doctor Scientiae - DSc
In this study novel composite electrodes were developed, in which the catalytic components were deposited in nanoparticulate form. The efficiency of the nanophase catalysts and membrane electrodes were tested in an important electrocatalytic process, namely hydrogen production by water electrolysis, for renewable energy systems. The activity of electrocatalytic nanostructured electrodes for hydrogen production by water electrolysis were compared with that of more conventional electrodes. Development of the methodology of preparing nanophase materials in a rapid, efficient and simple manner was investigated for potential application at industrial scale. Comparisons with industry standards were performed and electrodes with incorporated nanophases were characterized and evaluated for activity and durability.
South Africa

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42

Chen, Yu-Ming. "The Fabrication of Advanced Electrochemical Energy Storage Devices With the integration of Ordered Nanomaterial Electrodes." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron148553322128565.

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Pelletier, Bérengère. "Caractérisation approfondie de copolymères triblocs PS-b-POE-b-PS utilisés en tant qu'Electrolytes Polymères Solides pour les batteries Lithium-Métal-Polymère." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4730/document.

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Aujourd’hui, la recherche sur les technologies de stockage d’énergie connaît un essor important dû au fort développement de l’électronique portable et des modes de transport écologiques. La plupart des batteries commercialisées utilisent des électrolytes liquides ou à base de liquides qui limitent leur stabilité thermique, la densité d’énergie et la sécurité. Ces limitations pourraient être considérablement diminuées par l’utilisation d’électrolytes polymères solides (SPE) et la technologie lithium métal polymère (LMP). L’objectif des SPE est de combiner au sein du même matériau une conductivité ionique élevée et une tenue mécanique suffisante pour éviter la formation de dentrites de lithium. Dans ce contexte, les copolymères triblocs PS-b-POE-b-PS, avec le POE comme bloc conducteur et le bloc PS apportant la résistance mécanique, sont d’excellents candidats. Afin d’établir des corrélations composition/morphologie/performance, le but de mes travaux de thèse est d’obtenir une caractérisation détaillée des copolymères à blocs synthétisés. Ainsi, les PS-b-POE-b-PS synthétisés (NMP) ont été analysés par chromatographie liquide aux conditions limites de désorption LC LCD. De plus, les analyses de la nano structuration (AFM, TEM et SAXS), des propriétés thermiques (DSC) et mécaniques (DMA) sont discutées. Enfin, des mesures d’impédance ont été effectuées via des cellules symétriques Lithium/ Electrolyte/ Lithium
The research on electrochemical storage of energy is today in a stage of fast and profound evolution owing to the strong development of portable electronics requesting power energy as well as the requirement of greener transport modes. Most commercial batteries use liquid or liquid-based electrolytes, which limits their thermal stability, energy density and safety. These limitations could be considerably offset by the use of solid polymer electrolytes (SPE) and lithium metal polymer technology (LMP). However, the main drawback of the SPE is the decrease of the ionic conductivity with increasing mechanical strength, necessary to avoid the formation of lithium dendrites during the recharge of the battery. In this context, triblock copolymers PS-b-PEO-b-PS with a PEO block as ionic conductor and PS block providing mechanical strength was a promising candidate as SPE. In order to build composition/morphology/performance relationships, the aim of my PhD is to characterize carefully the block copolymer. For that purpose, the PS-b-PEO-b-PS synthesized (NMP) were characterized using Liquid Chromatography under Limiting Conditions of Desorption (LC LCD). Furthermore, analyses of morphologies and nano-structure by Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM) and Small Angle X-ray Scattering (SAXS) techniques, analyses of thermal (DSC) and mechanical (DSC) properties will be also discussed. Finally, measures of impedance were made via symmetric cells Lithium / Electrolyte / Lithium

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44

Li, Shuai. "Preparation and characterization of perovskite structure lanthanum gallate and lanthanum aluminate based oxides." Doctoral thesis, Stockholm : Skolan för industriell teknik och management, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10588.

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45

Baradie, Bilal. "Membranes ionomères composites pour piles à combustibles H2/O2 : élaboration et caractérisation." Grenoble INPG, 1997. http://www.theses.fr/1997INPG0002.

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Dans le but de fournir une alternative aux membranes perfluorees pour piles a combustible a electrolyte polymere, plusieurs membranes polymeres a conduction protonique ont ete elaborees et caracterisees leurs proprietes electrochimiques et physiques, notamment leur stabilite mecanique et thermique, ont ete etudiees. La premiere famille de membranes est obtenue, par dispersion d'une poudre inorganique superconductrice protonique (h#3sb#3p#2o#1#4,xh#2o, = 10#-#2s. Cm#-#1) dans une matrice polymere commerciale epdm. Malgre leurs conductivites assez elevees, ces membranes composites ne repondent pas aux exigences requises, en raison de la chute ohmique qu'elles occasionnent et de leur permeabilite aux gaz. Dans la deuxieme approche, nous avons selectionne, comme matrice polymere, un ionomere thermoplastique, pss, ce dernier etant prepare par sulfonation du poly (arylene ether sulfone). Ces membranes composites repondent au cahier des charges des piles a combustible a membrane echangeuse de proton, notamment en matiere de stabilite thermique, mecanique et electrochimique ; leur conductivite protonique etant voisine de celle de nafion# 117. De plus, elles presentent une permeabilite aux gaz bien inferieure a celle du nafion# 117 et ont ete evaluees avec succes sur un banc de test pendant 500 heures. Enfin, leur prix assez faible permettrait d'envisager une industrialisation dans un proche avenir.

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46

Sundin, Camilla. "Environmental Assessment of Electrolyzers for Hydrogen Gas Production." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-260069.

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Hydrogen has the potential to become an important energy carrier in the future with many areas of applications, as a clean fuel for transportation, heating, power generation in places where electricity use is not fit, etc. Already today hydrogen plays a key role in numerous industries such as petroleum refineries and chemical industries. There are different production methods for hydrogen. Today, natural gas reforming is the most commonly used. With the growing importance of green production paths, hydrogen production by electrolysis is expected to grow. Two main electrolyzer technologies are used today; alkaline and polymer electrolyte membrane electrolyzer. High-temperature electrolyzers are also interesting techniques, where solid oxide is under development and molten carbonate electrolyzers is researched. In this thesis, a comparative life cycle analysis was performed on the alkaline and molten carbonate electrolyzer. Due to inaccurate inventory data for the molten carbonate electrolyzer, those results are excluded from the published thesis. The environmental performance of the alkaline electrolyzer technology was compared to that of the solid oxide and the polymer electrolyte membrane electrolyzers. The system boundaries were set as cradle to gate. Thereby, the life cycle steps included in the study are raw material extraction, electrolyzer manufacturing, hydrogen production, and transports in between these steps. The functional unit was chosen as 100 kg produced hydrogen gas. The results show that the polymer electrolyte membrane electrolyzer has the lowest environmental impact out of the compared technologies. It is also determined that the lifetime and the current density of the electrolyzers have significant impact on their environmental performance. Moreover, it is established that electricity for hydrogen production has the highest environmental impact out of the electrolyzers life cycle steps. Therefore, it is important to make sure that the electricity used for hydrogen production derives from renewable sources.
Vätgas har potential att spela en viktig roll som energibärare i framtiden med många användningsområden, såsom ett rent bränsle för transporter, uppvärmning, kraftförsörjning där elproduktion inte är lämpligt, med mera. Redan idag är vätgas ett viktigt inslag i flera industrier, där ibland raffinaderier och kemiska industrier. Det finns flera metoder för att producera vätgas, där reformering av naturgas är den största produktionsmetoden idag. I framtiden spås vätgasproduktion med elektrolys bli allt viktigare, då hållbara produktionsprocesser prioriteras allt mer. Idag används främst två elektrolysörtekniker, alkalisk och polymerelektrolyt. Utöver dessa är högtemperaturelektrolysörer också intressanta tekniker, där fastoxidelektrolysören är under utveckling och smältkarbonatelektrolysören är på forskningsstadium. I det här examensarbetet har en jämförande livscykelanalys utförts på alkalisk- och smältkarbonatelektrolysören. På grund av felaktiga indata för smältkarbonatelektrolysören har dessa resultat uteslutits från den publika rapporten. Miljöpåverkan från den alkaliska elektrolysören har sedan jämförts med miljöpåverkan från fastoxid- och polymerelektrolytelektrolysörerna. Systemgränserna sattes till vagga till grind. De livscykelsteg som inkluderats i studien är därmed råmaterialutvinning, elektrolysörtillverkning, vätgasproduktion och transporter mellan dessa steg. Den funktionella enheten valdes till 100 kg producerad vätgas. Resultaten visar att polymerelektrolytteknologin har den lägsta miljöpåverkan utav de tekniker som jämförts. Resultaten påvisar också att livstiden och strömtätheten för de olika teknikerna har signifikant påverkan på teknikernas miljöpåverkan. Dessutom fastslås att elektriciteten för vätgasproduktion har högst miljöpåverkan utav de studerade livscykelstegen. Därför är det viktigt att elektriciteten som används för vätgasproduktionen kommer ifrån förnybara källor.

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47

Takahashi, Masakuni. "Elucidation of the Dominant Factor in Electrochemical Materials Using Pair Distribution Function Analysis." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263748.

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京都大学
新制・課程博士
博士(人間・環境学)
甲第23287号
人博第1002号
京都大学大学院人間・環境学研究科相関環境学専攻
(主査)教授内本喜晴, 教授田部勢津久, 准教授戸﨑充男
学位規則第4条第1項該当
Doctor of Human and Environmental Studies
Kyoto University
DFAM

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48

Crisanti, Samuel Nathan Crisanti. "Effect of Alumina and LAGP Fillers on the Ionic Conductivity of Printed Composite Poly(Ethylene Oxide) Electrolytes for Lithium-Ion Batteries." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1522756200308156.

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49

Pelletier, Bérengère. "Caractérisation approfondie de copolymères triblocs PS-b-POE-b-PS utilisés en tant qu'Electrolytes Polymères Solides pour les batteries Lithium-Métal-Polymère." Electronic Thesis or Diss., Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4730.

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Aujourd’hui, la recherche sur les technologies de stockage d’énergie connaît un essor important dû au fort développement de l’électronique portable et des modes de transport écologiques. La plupart des batteries commercialisées utilisent des électrolytes liquides ou à base de liquides qui limitent leur stabilité thermique, la densité d’énergie et la sécurité. Ces limitations pourraient être considérablement diminuées par l’utilisation d’électrolytes polymères solides (SPE) et la technologie lithium métal polymère (LMP). L’objectif des SPE est de combiner au sein du même matériau une conductivité ionique élevée et une tenue mécanique suffisante pour éviter la formation de dentrites de lithium. Dans ce contexte, les copolymères triblocs PS-b-POE-b-PS, avec le POE comme bloc conducteur et le bloc PS apportant la résistance mécanique, sont d’excellents candidats. Afin d’établir des corrélations composition/morphologie/performance, le but de mes travaux de thèse est d’obtenir une caractérisation détaillée des copolymères à blocs synthétisés. Ainsi, les PS-b-POE-b-PS synthétisés (NMP) ont été analysés par chromatographie liquide aux conditions limites de désorption LC LCD. De plus, les analyses de la nano structuration (AFM, TEM et SAXS), des propriétés thermiques (DSC) et mécaniques (DMA) sont discutées. Enfin, des mesures d’impédance ont été effectuées via des cellules symétriques Lithium/ Electrolyte/ Lithium
The research on electrochemical storage of energy is today in a stage of fast and profound evolution owing to the strong development of portable electronics requesting power energy as well as the requirement of greener transport modes. Most commercial batteries use liquid or liquid-based electrolytes, which limits their thermal stability, energy density and safety. These limitations could be considerably offset by the use of solid polymer electrolytes (SPE) and lithium metal polymer technology (LMP). However, the main drawback of the SPE is the decrease of the ionic conductivity with increasing mechanical strength, necessary to avoid the formation of lithium dendrites during the recharge of the battery. In this context, triblock copolymers PS-b-PEO-b-PS with a PEO block as ionic conductor and PS block providing mechanical strength was a promising candidate as SPE. In order to build composition/morphology/performance relationships, the aim of my PhD is to characterize carefully the block copolymer. For that purpose, the PS-b-PEO-b-PS synthesized (NMP) were characterized using Liquid Chromatography under Limiting Conditions of Desorption (LC LCD). Furthermore, analyses of morphologies and nano-structure by Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM) and Small Angle X-ray Scattering (SAXS) techniques, analyses of thermal (DSC) and mechanical (DSC) properties will be also discussed. Finally, measures of impedance were made via symmetric cells Lithium / Electrolyte / Lithium

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50

Issa, Sébastien. "Synthèse et caractérisation d'électrolytes solides hybrides pour les batteries au lithium métal." Electronic Thesis or Diss., Aix-Marseille, 2022. http://www.theses.fr/2022AIXM0046.

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Les problématiques engendrées par l’extraction et l’utilisation intensives des ressources fossiles ont forcé l’humanité à se tourner vers le développement d’énergies renouvelables et de véhicules électriques. Cependant, ces technologies doivent être couplées à des moyens de stockage de l’énergie efficaces pour exploiter leur potentiel. Les systèmes embarquant une anode de lithium métallique sont particulièrement intéressants car ils présentent une densité d’énergie élevée. Cependant, cette technologie souffre de la formation de dendrites pouvant déclencher des courts-circuits provoquant l’explosion du dispositif. Ainsi, de nombreux efforts ont été consacrés à l’élaboration d’électrolytes solides polymères (SPE) à base de POE permettant de constituer une barrière qui bloque la croissance dendritique tout en préservant les propriétés de conduction ionique. Cependant, la conductivité ionique des SPE à base de POE décroît fortement avec la température. A l’heure actuelle, les meilleurs SPE de la littérature nécessiteraient de fonctionner à 60 °C, ce qui signifie qu’une partie de l’énergie de la batterie sera détournée de son utilisation pour maintenir cette température. Ainsi, l’objectif principal de ce travail de thèse est de concevoir un SPE permettant le fonctionnement de la technologie de batterie au lithium métal à température ambiante. Ces SPE doivent présenter une conductivité ionique élevée à température ambiante (≈ 10-4 S.cm-1) et des propriétés mécaniques permettant l’inhibition du phénomène de croissance dendritique. Pour cela, les objectifs du projet sont focalisés sur le développement de nouveaux SPE nanocomposites et hybrides
The problems caused by the intensive extraction and use of fossil fuels have forced humanity to turn to the development of renewable energies and electric vehicles. However, these technologies need to be coupled with efficient energy storage means to exploit their potential. Lithium metal anode systems are particularly interesting because they have a high energy density. However, this technology suffers from the formation of dendrites that can trigger short circuits causing the device to explode. Thus, many efforts have been devoted to the development of POE-based solid polymer electrolytes (SPEs) that provide a barrier that blocks dendritic growth while preserving ionic conduction properties. However, the ionic conductivity of POE-based SPEs decreases strongly with temperature. Currently, the best SPEs in the literature would require operation at 60 °C, which means that some of the energy in the battery will be diverted from its use to maintain this temperature. Thus, the main objective of this thesis work is to design an SPE that allows the operation of lithium metal battery technology at room temperature. These SPEs must exhibit high ionic conductivity at room temperature (≈ 10-4 S.cm-1) and mechanical properties that allow the inhibition of the dendritic growth phenomenon. For this, the objectives of the project are focused on the development of new nanocomposite and hybrid SPEs

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Dissertations / Theses on the topic 'Solid Polymer Electrolyte'

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