Application In Organic Batteries Research Articles

Physical and Chemical Characterization of Commercial Kappa-Carrageenan with Ammonium Chloride as Electrolyte in Organic Battery Application

In this research, we attempt to investigate the difference in physical and chemical characteristics of commercial kappa-carrageenan and purified kappa-carrageenan as electrolytes in organic battery applications. Kappa-carrageenan was used as a host polymer to prepare biopolymer electrolyte films and ammonium chloride was used to enhance the charge transport process in the electrolyte layer of the organic battery. We characterized the physical and chemical properties of commercial kappa-carrageenan and purified kappa-carrageenan by use of UV-Vis spectroscopy, tensile-test measurement, Fourier Transform infrared spectroscopy and Raman spectroscopy in the form of solution and thin film samples. The results show that commercial kappa-carrageenan shows the absorbance area in Ultraviolet range with a maximum peak at 286 nm, while the maximum absorbance peak of purified kappa-carrageenan is slightly shifted at 288 nm. The chemical characterization of both kappa-carrageenan based on FTIR and Raman spectra show no significant structural change between kappa-carrageenan with or without the addition of ammonium chloride. XRD diffraction confirms that commercial kappa-carrageenan is amorphous and kappa-carrageenan with ammonium chloride has high intensity with sharp peaks around 2θ = 32º. The morphology of the thin film of purified kappa-carrageenan seem has a rougher surface in comparison to the commercial kappa-carrageenan. We found commercial kappa-carrageenan with ammonium chloride has high conducting about 1.55 x 10-5 Scm-1. Tensile test measurements indicate that commercial kappa-carrageenan is more flexible for use as an organic battery than the purified kappa-carrageenan.

New TEMPO containing polymers for all polymeric oxidation procedure

2,2,6,6-Tetramethylpiperidine 1-oxyl (TEMPO) is a versatile compound which is used mainly in organic oxidation reactions and organic battery applications. Incorporating TEMPO into a polymer could provide many applications into its repertoire. In this study, new polymeric TEMPO derivatives are synthesized and characterized to be used as catalysts in the presence of another polymer which constitutes N-halamine functionality. These polymeric mixtures were superior since the mixture could easily be separated from the reaction medium by simple filtration and reused in some other oxidation reactions numerous times. In turn, an all polymeric oxidation method was developed for oxidation of primary alcohols.

Crosslinkable Nitroxide Radical Polymer for Energy Storage Applications

Due to the amount of waste generated by lithium ion batteries (LIB) disposal, a more environmentally friendly option such as organic batteries, is desired to fulfill the need of this large market. For many years, alternatives to LIBs have been researched, including the use of conductive polymers for completely organic batteries. Redox-active polymers, such as conjugated polyaniline and organic radical poly(2,2,6,6-tetramethylpiperidinyloxy-4-ylmethacrylate) (PTMA), are being studied as electrode materials for organic batteries. As linear PTMA may dissolve in the electrolyte solution and thus degrade battery capacity, crosslinked PTMA is gaining interest as a cathode material. A balance must be struck, however, as diffusion of the electrolyte solution into the polymer may become limited at sufficiently high crosslink density. To balance these competing mechanisms, a random copolymer consisting of PTMA monomer and glycidyl methacrylate (GMA), a UV and thermally crosslinkable monomer, is synthesized (P(TMA-GMA)) and the mechanism of redox activity is studied. This new PTMA copolymer is synthesized using free radical chain-growth polymerization and is then oxidized to produce the characteristic organic radical. Linear P(TMA-GMA) is characterized using UV-VIS, NMR spectroscopy, and gel permeation chromatography. The effect of crosslinking on the thermal properties and the temperature for thermally induced crosslinking is analyzed using differential scanning calorimetry. The crosslink density is calculated for each composition using the linear P(TMA-GMA) molecular weight and solvent uptake of the crosslinked P(TMA-GMA). Determining the most favored crosslink density is necessary for balancing electrolyte diffusion with the dissolution of the polymer. The electrochemical properties of the crosslinked P(TMA-GMA) is studied using cyclic voltammetry (CV) to determine if crosslinking impacts the redox properties. Preliminary results have found that the crosslinked P(TMA-GMA) exhibits a change in the shape of the CV curve and peak heights, associated with some change in the crosslinked polymers electroactivity. In addition, the crosslink density of the P(TMA-GMA) with 5 mol% GMA is quantified and is similar to previous studies of poly(ethylene glycol). Finally, the thermal properties are represented by a glass transition temperature that did not significantly change with varying GMA content. This new P(TMA-GMA) shows promise for application in organic batteries by providing a processable yet crosslinkable alternative to PTMA.

PNTQS: Easily Accessible High-Capacity Redox-Active Polymer for Organic Battery Electrodes

Despite a continuous effort to develop novel materials for organic polymer-based batteries, their commercial success is still hampered by the demanding synthesis and the high costs of these materials. To overcome these issues, we developed poly(naphthotriazolequinonestyrene) (pNTQS), the first redox-active polymer bearing naphthotriazolediones, and have demonstrated its promising characteristics for an application in organic batteries. The polymer is effectively synthesized using a straightforward cycloaddition reaction followed by a free-radical polymerization. The electrochemical investigations of this new material reveal a two-electron storage capability, and an electrolyte system optimized for use in Li–organic batteries was established. Coin cells comprising pNTQS as active electrode material reveal an excellent capacity of 135 mAh g–1, which exceeds most of the commonly applied polymer-based materials, while a capacity loss of only 30% over 1000 cycles was observed.

Investigation of Ice-Templated Porous Electrodes for Application in Organic Batteries.

Application and investigation of porous composite electrodes for organic batteries fabricated by an ice-templating method are reported for the first time. The possibility to produce polymer composite electrodes with highly aligned, parallel pores is demonstrated and electrochemical investigations are presented to examine their suitability for application in organic batteries. The performance of such ice-templated porous electrodes is experimentally compared with planar electrodes of similar composition against zinc and lithium counter electrodes, respectively. Fundamental properties limiting the performance of ice-templated porous electrodes are discussed and further means to overcome those limitations are proposed.

PolyTEMPO and polyviologen on carbon nanotubes: syntheses, structures and organic battery applications

Scanning tunneling microscopy of semiconducting carbon nanotubes (sc-CNTs) treated with four redox active linear polymers shows throughout complex formation by helical wrapping. The compounds used are polyTEMPO I (poly-acetylene backbone and TEMPO side chain, new compound), polyTEMPO II (polymethacrylate backbone and TEMPO side chain), polyviologen I (main chain polyamide of diaminopropyl viologen and isophthalic acid), polyviologen II (main chain bipyridine dibromoxylene polymer)). Monomer subunit resolution was achieved in case of polyTEMPO I and II. Redox activity, such as in the TEMPO and viologen polymers is claimed crucial for electrostatically driven wrapping. Complex formation was modeled with the MM+ force field. No evidence of polymer complex formation was experimentally found with metallic CNTs and with vapor grown carbon fibers (VGCFs), possibly because of “charge trapping” exclusively on the semiconducting nanotubes. Composite electrodes (cathods) were prepared according to polyTEMPO I or II/VGCF and or sc-CNTs/poly-vinylidene fluoride (PVDF) and studied vs. a lithium electrode. polyTEMPO I has a higher theoretical capacity than the standard polyTEMPO II (127 and 111mAh/g, respectively), but other specifications of polyTEMPO I, such as stability during cycling and potential vs. Li are inferior. The ratio of CNTs and VGCF used in the composite electrode does not influence the battery performance.