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The aim of this thesis was to examine whether it is beneficial to automate yeast transformation protocol and what benefits and limitations it might have. There is variation in pipetting techniques between people, and with automation it is possible to remove the variation. In addition, larger the sample sizes and smaller the pipetting volumes, the more useful automation becomes especially with highthroughput analysis. A quantitative research method was used in this study as the manual and automated transformation methods were compared. It was possible to get clear results and data from the methods. Saccharomyces cerevisiae yeast was selected to be transformed with an empty plasmid pYX212 with lithium acetate/ PEG method. Transformation mix was done with pipetting of different liquids either manually or with using liquid-handling robots. Colonies were calculated using a cell clicker, and transformation efficiency, active time and total time were compared between manual and automated methods. It is concluded that automation of yeast transformation is useful especially with larger sample sets saving active time and preventing from work-related repetitive strain injuries. Transformation efficiency was better with manual method, but the time for developing automated method was limited and the protocol can be further developed to work better.

The aim of this thesis was to examine whether it is beneficial to automate yeast transformation protocol and what benefits and limitations it might have. There is variation in pipetting techniques between people, and with automation it is possible to remove the variation. In addition, larger the sample sizes and smaller the pipetting volumes, the more useful automation becomes especially with highthroughput analysis. A quantitative research method was used in this study as the manual and automated transformation methods were compared. It was possible to get clear results and data from the methods. Saccharomyces cerevisiae yeast was selected to be transformed with an empty plasmid pYX212 with lithium acetate/ PEG method. Transformation mix was done with pipetting of different liquids either manually or with using liquid-handling robots. Colonies were calculated using a cell clicker, and transformation efficiency, active time and total time were compared between manual and automated methods. It is concluded that automation of yeast transformation is useful especially with larger sample sets saving active time and preventing from work-related repetitive strain injuries. Transformation efficiency was better with manual method, but the time for developing automated method was limited and the protocol can be further developed to work better.

In this research, poly(acrylamide) hydrogels were produced by means of free radical mechanism. Lithium acetate with different weight percentages (wt.%) such as 10 wt.%, 20 wt.%, 30 wt.%, and 40 wt.% as a source of mobile ions were incorporated into the hydrogel, and the samples were labeled as LAM1, LAM2, LAM3, and LAM4, respectively. The electrochemical impedance spectroscopy (EIS) revealed that LAM4 hydrogel electrolyte achieved the highest ionic conductivity of 9.45 × 10−3 Scm−1 with lowest activation energy (0.038 eV) at ambient temperature. The electrochemical performance of the fabricated supercapacitors using optimized LAM4 hydrogel electrolyte and different conducting substrates namely graphite foil, nickel foam, and carbon cloth was analyzed. The cyclic voltammetry and galvanic charge–discharge analyses reported that EDLC with carbon cloth resulted in maximum specific capacitance of 198.64 F g−1 at 5 mV s−1 and 439.87 F g−1 at 500 mA g−1, respectively.

In this work, the water-controlled release solvothermal process (WCRSP) method was selected to synthesize nanostructured β-Li2TiO3 tritium breeder ceramic pebbles using anhydrous lithium acetate (LiOAc) as lithium source and tetrabutyl titanate (TBOT) as titanium source. The effects of the reaction system, temperature, and amount of acetic acid on the crystal structure and morphology of Li2TiO3 power were systematically investigated by using XRD, SEM, and TEM techniques, respectively. The urea or acetone in the reaction system affects the composition of Li2TiO3 in the water-controlled release solvothermal process at 550 °C. Initially, the nanostructured single-phase Li2TiO3 powders with good dispersion and an average particle size of 35 nm were successfully synthesized at 550 °C when the acetic acid content was 15 vol%. Moreover, the phase transition temperature for the monoclinic phase β-Li2TiO3 was as low as 450 °C. The morphology of Li2TiO3 powder presents two different shapes, one is micro-spherical, the other is spherical nanoparticles in different content acetic acid. The results indicate that using ethanol/acetic acid mixture as a reaction system is favorable for obtaining nanostructured Li2TiO3 powder. Finally, Li2TiO3 ceramic pebbles with grain size of 1.4 μm were successfully fabricated at 950 °C for 2 h at room temperature, and the crush load and relative density (theoretical density, T.D) of the pebbles reach 53 N and 85.2%, respectively.

The vaporization of lithium pivalate (CH3)3CCOOLi (LiPiv) was studied by the Knudsen effusion method with the mass spectral analysis of the gas phase. The saturated vapor consisted of polynuclear molecules (LiPiv)n, dominated by (LiPiv)2 and (LiPiv)4 molecules. The absolute values of the partial pressures of these molecules and their dependence on temperature were calculated. The standard enthalpies of sublimation of the main components of the saturated vapor were determined to be $${{\Delta }_{s}}H_{{298}}^{^\circ }$$ (LiPiv)2 = 174.2 ± 6.6 kJ/mol and $${{\Delta }_{s}}H_{{298}}^{^\circ }$$ (LiPiv)4 = 195.7 ± 4.5 kJ/mol. The enthalpies of dissociation of the dimeric molecules into the monomeric molecules and of the tetrameric molecules into the dimeric molecules were calculated by the second and third laws of thermodynamics; the average values of these enthalpies are $${{\Delta }_{D}}H_{{298}}^{^\circ }$$ (LiPiv)2 = 175.8 ± 13.5 kJ/mol and $${{\Delta }_{D}}H_{{298}}^{^\circ }$$ (LiPiv)4 = 155.2 ± 10.0 kJ/mol. The standard enthalpies of formation of LiPiv in the condensed and gas phase were estimated from the known thermodynamic characteristics of lithium acetate and radicals of acetic and pivalic acids: $${{\Delta }_{f}}H_{{298.15}}^{^\circ }$$ (LiPivsolid) ≤ –804 kJ/mol, $${{\Delta }_{f}}H_{{298.15}}^{^\circ }$$ (LiPivgas) ≤ –627 kJ/kmol, $${{\Delta }_{f}}H_{{298.15}}^{^\circ }$$ ((LiPiv)2(gas)) ≤ –1430 kJ/mol, and $${{\Delta }_{f}}H_{{298.15}}^{^\circ }$$ ((LiPiv)4(gas)) ≤ –3017 kJ/mol.

Due to the theoretical ultrahigh energy density of the Li-O2 battery chemistry, it has been hailed as the ultimate battery technology. Yet, practical Li-O2 batteries usually need to be designed in a large-sized pattern to actualize a high specific energy density, and such batteries often cannot be cycled effectively. To understand the inherent reasons, we specially prepared large-sized (13 cm × 13 cm) Li-O2 model batteries with practical energy output (6.9 Ah and 667.4 Wh/kgcell) for investigations. By subregional and postmortem analysis, the cathode interface was found to have severe local inhomogeneity after discharge, which was highly associated with the electrolyte and O2 maldistribution. The quantitative results by X-ray photoelectron spectroscopy (XPS) evidenced that this local inhomogeneity can exacerbate the generation of lithium acetate during charge, where the locally higher ratio of unutilized carbon surface and less Li2O2 after discharge would result in increased lithium acetate formation for a subsequent local overcharge. Moreover, verification experiments proved that the byproduct lithium acetate, which had been of less concern, was recalcitrant and triggered much larger polarization compared with the commonly reported byproduct Li2CO3 during battery operations, further revealing the key limiting factors leading to the poor rechargeability of batteries by its accumulation at a pouch-type cell level.

3D porous nano-LiMn2O4 (nano-LMO) is successfully prepared at 250 °C by a low temperature pyrolysis, using porous MnO2 and lithium acetate as reactants. The as-formed porous samples are demonstrated to be constructed by well-defined and uniform cubic nanocrystals with particle sizes regulated from tens to hundreds of nanometers by adjusting the annealing temperature. Due to its proper particle size with perfect crystallization (∼50 nm) and rich pores, sample LMO-265, prepared at 265 °C, exhibits high performance as an aqueous lithium ion cathode. It can present a high specific capacity of 102 mAh g−1 at a current density of 5C with a greatly improved rate capability (57.3%, 68C) and capacity retention (70.7%, after 5000 cycles at 13.5C) in 1 M Li2SO4. When assembled with commercial used active carbon (AC) to form an aqueous hybrid capacitor, it can deliver a high energy density of 15.8 Wh kg−1 at a large power density of 9 kW kg−1 with a good cycling life of 71.6% after 5000 at 2 A g−1. Considering of its simple and economical preparation, as-prepared porous LMO can be regarded as a promising high-performance cathode material in aqueous electrolyte.

In this study, infrared (IR) and visible transparent MgO ceramics were obtained by spark plasma sintering of in-situ synthesized of LiF decorated MgO nanoparticles (MgO–LiF nanocomposite). Lithium acetate (LiAC), trifluoroacetic acid (TFA), oleic acid (OA), and absolute ethanol were used as in-situ synthesis of the LiF phase covered on MgO nanoparticles. TFA/Li (AC) mole ratio, pH, and calcination temperature were changed to obtain the MgO–LiF nanocomposite. The results revealed that with Li (AC)/TFA = 1.5:0.5 and pH = 6 at the calcination temperature of 700 °C, in situ MgO–LiF nanocomposites were well prepared. The SPSed MgO covered with a 0.5% LiF sample showed 30% more visible and IR transmittance than pure MgO bodies sintered at 1100 °C for 10 min.

We report the physicochemical and electrochemical properties of various concentrations of potassium and lithium acetate (OAc) electrolytes from dilute to near saturation as well as mixed potassium/lithium acetate (32 m KOAc + 8 m LiOAc). The electrochemical stability window varied in the order of Pt < Au < highly ordered pyrolytic graphite (HOPG) < glassy carbon electrodes, and expanded when the salt concentration increased reaching 3.5 V in the dual cation water-in-salt electrolyte. This increase was due to the shift in the onset potential of the hydrogen evolution and oxygen evolution reactions to more negative and positive potential values, respectively. It is noteworthy that there is a larger shift in the onset potential of the oxygen evolution on the Pt electrode. The capacitance at the potential of zero charge of the HOPG electrode was found to be about 4 μF cm−2 and almost independent of the electrolyte concentration while the potential of zero charge shifted to more negative values upon increasing the acetate salt concentration. Using ferricyanide and ferrocene methanol as redox probes, their redox potential, ion transport and electron transfer kinetics in acetate-based electrolytes were investigated. The apparent redox potential shifted in the opposite direction; to more positive and negative values for ferricyanide and ferrocene methanol redox systems, respectively. A significant decrease in the diffusion coefficient of ferricyanide ions, i.e. 4 orders of magnitude, was observed in the dual cation water-in-salt compared to a dilute single salt electrolyte. High viscosities might be partially responsible for the decrease of the heterogeneous rate constants obtained for the redox probes but other factors such as interactions with water, electrolyte ions and electrodes might be at play as well.

In this paper, the single-phase Li2TiO3 powder was successfully synthesized via non-hydrolytic sol-gel method (NHSG) using anhydrous lithium acetate (LiOAc) as lithium source and tetrabutyl titanate (TBOT) as titanium source. The effects of the temperature and the Li/Ti molar ratio on the synthesis of Li2TiO3 were investigated by XRD. FT-IR and XPS were used to characterize the synthesis mechanism and surface chemistry of Li2TiO3 powder heated at 650 °C for 2 h with 5 °C/min. Furthermore, the Li2TiO3 pebbles were successfully prepared using synthesized powder by indirect wet chemistry method. The results showed that the Li2TiO3 pebbles with diameter of 1.3mm–1.5 mm, crush load of 67 N, sphericity of 0.97, the relative density of 84.9%, the grain size of 2.85 μm and porosity of 19.84% were successfully fabricated when sintering temperature was 1050 °C for 2 h in air. Therefore，the NHSG method could provide a new efficient route for the production of Li2TiO3 ceramic pebbles.

A nanocomposite solid polymer electrolyte (SPE) system has been prepared for application in a supercapacitor. Corn starch is used to host the ionic conduction with lithium acetate (LiOAc) salt as an ion provider. Different concentrations of nanosized titanium dioxide (TiO2) filler have been added to analyse the influence of nanofiller addition on the conductivity and other properties of the electrolytes. Structural characterisation and complex formation have been examined by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy, respectively. It is shown that the room temperature conductivity changes with the change in TiO2 concentration. Adding 4 wt.% TiO2 to the starch-LiOAc complex leads to an optimum conductivity of (8.37 ± 1.04) × 10−4 S cm−1. The variation in conductivity is accompanied by the change in surface morphology as observed from field emission scanning electron microscopy (FESEM) analysis. Linear sweep voltammetry (LSV) indicates that the electrochemical potential stability window of the electrolyte with 4 wt.% TiO2 lies in the range between − 2.0 and + 1.9 V. A supercapacitor has been assembled using the electrolyte, and its performance has been characterised using impedance technique and cyclic voltammetry.

We report on the first example of a peroxouranium-containing {P8W48} wheel, [{(UO2)4(O2)4}2(P8W48O184)]40- (1), which was synthesized by a one-pot reaction of UO2(NO3)2·6H2O with the 48-tungsto-8-phosphate wheel [H7P8W48O184]33- and aqueous hydrogen peroxide in a pH 6 lithium acetate solution at 50 °C. Polyanion 1 comprises two tetrauranyl squares with side-on peroxo bridging ligands in the cavity of the {P8W48} wheel, and was isolated as the hydrated potassium-lithium salt K18Li22[{(UO2)4(O2)4}2(P8W48O184)]·133H2O (KLi-1), which was characterized in the solid state by single-crystal X-ray diffraction, as well as thermogravimetric and elemental analyses. A detailed Fourier transform infrared and Raman spectroscopy study was also performed.

Lithium-doped zinc oxide (Zn0.99Li0.01O) film was manufactured by the sol-gel method using uniform and stable solution of zinc acetate dehydrate and lithium acetate dehydrate in methanol. Films were deposited by spin-coating using spinner between 4500 and 5000 rpm on silicon substrates. The prepared samples were sintered at various temperatures (600 ℃ ~ 1000 ℃) in the air. The structural, morphological, and optical properties of the prepared lithium-doped ZnO films were investigated. The XRD pattern of Zn0.99Li0.01O film demonstrated the hexagonal wurzite structure. However, new crystal phase was discovered at a sintering temperature of 800 ℃. New peak was found near 2θ = 22.6˚ in XRD patterns. The peak is thought to be the (101) plan in SiO2 cristobalite structure. Moreover, another new crystal phase related to Li2SiO5 was occurred at a sintering temperature of 900 ℃. From XRD analysis, it was confirmed that C axis was decreased and the stress was increased, as sintering temperatures was increased from 600 ℃ to 900 ℃. In cathodo luminescence (CL) data, zinc oxide usually appears ultra violet and green emission. However, the green emission did not appear in all these samples used in this study. The ultra violet emission showed red shift from 600 ℃ to 800 ℃ in the CL spectrum as the sintering temperature was increased. The phenomenon of the red shift can be explained in Burstein-Moss effect. At sintering temperature of 700 ℃, the intensity of ultra-violet emission was the largest and full width at half maximum (FWHM) was the smallest. (Received January 6, 2020; Accepted March 9, 2020)

Here lithium acetate modified PU/graphene composites were prepared from a simple electrospun method. The electrochemical properties, thermal stability, and mechanical properties of polyurethane (PU) separator have been improved remarkably by the addition of lithium acetate and graphene. The composite separator can maintain the dimension size even after being treated at 170°C for 1 h. High ionic conductivity of 2.47 mS·cm -1 can be reached. The results show that the as-prepared lithium acetate modified PU/graphene separator is a promising candidate for commercial polyolefin separators.

A lithium titanate (Li2TiO3) precursor colloid with high stability was synthesized via a novel inorganic precipitation–peptization method using low cost titanium sulfate as a titanium source, lithium acetate as a lithium source and hydrogen peroxide as a complexing agent. The formation mechanism of the precursor sol was discussed, and the effect of the addition of triethanolamine (TEOA) and sodium dodecylbenzenesulfonate (SDBS) on the colloidal stability was investigated in detail. Samples were characterized with thermogravimetric analysis–differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunnauer–Emmet–Teller (BET) analysis. The results indicate that the colloid stability is enhanced by increased dosage of TEOA and SDBS within a certain range. The best colloid stability is achieved when the amount of TEOA added is 0.75%, and the sol system can remain stable for up to 15 days, which is 7.5 times that of the precursor sol without added surfactant. The optimal amount of added SDBS is 0.125%, and the effect of SDBS on colloid stability is not as significant as that of TEOA. SDBS favors the formation of the crystal structure of Li2TiO3, while TEOA inhibits the ordered arrangement of Li+ in the main crystal layer. The sample (Li2TiO3) surface with SDBS shows a porous structure, which is conducive to the subsequent pickling treatment.

Synthesis of Lithium Manganese Oxide (LiMn2O4) for Lithium Ion Battery Cathodes with Solution Method has been conducted. This experiment was carried out using the solution method. In this study, the synthesis was carried out by varying the calcination temperature. The raw materials used were Lithium Acetate (C2H3O2Li), Manganese Acetate (C4H6MnO4.4H2O), Hydrochloric Acid (HCl), and Ethanol (C2H5OH) as solvents which were dissolved to become LiMn2O4 precursors. Synthesis was carried out at calcination temperatures of 600oC, 700oC and 800oC, for 4 hours then pounded with a mortar until smooth. The characterization includes: The results of the STA test at 280oC-380oC showed a mass decrease of 11.9973% due to the release of mass of water vapor and decomposition of C4H6MnO4.4H2O raw material. XRD analysis shows that the increase in peak temperature of the LiMn2O4 phase intensity is getting sharper, the peak showing the impurity Li2O phase decreases. SEM analysis results show that the higher the calcination temperature, the larger the particle size is formed, because in the calcination process the densification process occurs.

Recent increasing uses of ceria in research and industrial applications have fostered continuing developments of efficient routes to synthesize the material. Here we report our investigation of the effects and the mechanistic roles of lithium acetate to accelerate the growth of crystalline ceria nanoparticles in ozone-mediated synthesis. By increasing the mole ratio of the acetate to cerium nitrate in the reactions, the reaction yields of ceria nanoparticles were observed to increase from ca. 10% to up to over 90% by cerium content in 30 min reactions. Microscopy images and Raman spectra of the as-synthesized nanoparticles revealed that increasing the acetate additions led to a decrease in average particle size and size range but an increase in crystallinity. Through analyzing the organic by-products in the reaction mixtures, the acetate was inferred to base-catalyze the formation of acetals and cerium complexes and accelerate the formation of Ce–O–Ce bonds and hence the growth of ceria nanoparticles through alcohol-like condensation reactions.

Li4Ti5O12/C anode material for lithium-ion batteries were successfully synthesized by two-step calcination and sol-gel method using tetrabutyl titanate, lithium acetate, citric acid, and β-cyclodextrin as starting materials. The microstructure and morphology of the materials were characterized by X-ray diffractometer, scanning electron microscope, and transmission electron microscope. The electrochemical properties of the materials were conducted by constant current charge-discharge test, AC impedance, and cyclic voltammetry. The results show that the prepared Li4Ti5O12/C composites are spinel cubic crystal with good crystallinity and without other impurities. The particle size is between 50 and 200 nm. The electrochemical properties of Li4Ti5O12 are effectively improved by carbon coating. Among these composites, Li4Ti5O12 with 5% carbon coating shows the initial discharge specific capacity of 167.1 mAh/g at 5C and a 93.3% capacity retention after100 cycles. Its reversible capacity remains 125.4 mAh/g after100 cycles at a high charge-discharge rate of 20 C.

Production of effective and inexpensive new material used as a cathode for lithium ion batteries is the main topic of this study. Thin films of lithium chromium oxide (LiCrO2) were grown onto a glass substrate by spray pyrolysis using a chemical solution containing lithium acetate Li (CH3COO)2 and chromium trioxide (Cr2O3) as precursors. The depositions occurred in the substrate temperature range of 350°C. The investigation of the x-ray diffraction of the LiCrO2 thin films was displayed to be polycrystalline with a rhombohedral structure. The linear optical parameters, represented in the refractive index, energy gap and absorption coefficient of the LiCrO2 thin films were estimated via the transmittance and reflectance measurements. In the linear optical studies, the evaluated direct energy gaps of the LiCrO2 thin films could be observed decreased by increasing the film thickness. The dispersion refractive index data of the LiCrO2 thin films were analyzed according to the single oscillator model to evaluate the dispersion parameters including the dispersion energy, the optical dielectric constant and the oscillator energy. The nonlinear optical constants of the LiCrO2 thin films were calculated.

Lithium ion conducting poly(ethylene oxide) (PEO):poly(vinyl pyrrolidone) (PVP) polymer blend electrolytes have been prepared by solution casting technique. The XRD and FTIR analysis confirm the complexation between salt and polymers. The conductivity of the samples is analyzed by impedance spectroscopy technique within the frequency range of 42 Hz to 1 MHz in the temperature range of 303 to 363 K. The conductivity of polymer electrolytes increases up to 20 wt % of lithium acetate concentration and the higher conductivity is found to be 2.56 × 10–6 S/cm at room temperature. The transference number measurements are also carried out using Wagner polarization technique.

Li-ion conductive polycrystalline Li4B7O12Cl to be used as a solid-state electrolyte was successfully synthesized by an ionothermal route at a low temperature. The reaction of lithium acetate dihyd...

In this work the examination of analyte adduct formation by the application of both sodium acetate and lithium acetate was performed with salicylic acid used as a model drug. Additionally, on the basis of combined acetate salt based multiple analyte adduct ions it was aimed to investigate the generation of different analyte precursor ions and their application in signal separated quantification with liquid chromatography–tandem mass spectrometry. Adduct identification experiments were performed by infusion experiments and resulted in an optimised detection of analyte adduct ions with lithium acetate, sodium acetate and combined lithium acetate/sodium acetate. Sample preparation based on a fast protein precipitation with a methanol solution containing lithium acetate and sodium acetate. A Luna 5 μm C18 (2) 100 A, 150 mm × 2 mm analytical column and a mobile phase composed of an H2O/methanol = 3%/97% (v/v) solution with 10 mmol l-1 ammonium acetate and 0.1% acetic acid were used for chromatographic purposes. The linearity was investigated in the range of 5–500 μg/ml. The limit of detection (LOD of 1.2 μg/ml) and quantification (LOQ 4.0 μg/ml) together with other results of validation experiments revealed that this strategy can be applied for salicylic acid quantification.

In this work, the MgO-CO2 working pair has been adapted for thermochemical energy storage (TCES) at medium temperatures by the MgO modification with inorganic salts to promote the TCES dynamics. Brief screening of modifying salts showed that lithium acetate (LiOAc) and mixed lithium-potassium nitrate (Li0.42K0.58NO3) additives could considerably promote the MgO carbonation at P(CO2) ≤10 bar and T ≥300 °C. The de- and re-carbonation kinetics, as well as cycling stability of the doped MgO/MgCO3, was reported to outline possible TCES operating conditions (T = 280 °C–380 °C, P(CO2) = 0–1 bar). The heat storage capacity of the salt-promoted MgO was estimated to be 1.6 GJ/m3. A concept of chemical heat pump utilizing the MgO-CO2 working pair was discussed. The salt-promoted MgO-CO2 working pair was concluded to be promising for TCES.

Recently, spinel lithium titanate (Li4Ti5O12, LTO) has attracted attention as an anode material for lithium-ion batteries (LIBs). However, the poor electronic conductivity and low lithium-ion diffusion coefficient of LTO suppresses its electrochemical performance during quick charging. One possible way to improve the electrochemical performance is to reduce the LTO particle size to the nanometer range and modify the surface conductivity. In this study, LTO/C was synthesized by a one-step carbonization route without any specialized equipment using a resorcinol–formaldehyde (RF) resin as a carbon source, lithium acetate as a lithium source and polymerization catalyst, and commercial nano-sized TiO2 as a titanium source. The homogeneous mixing of the RF resin dissolved in water led to the uniform dispersion of the TiO2 and the Li source. The polymerization of the RF resin, TiO2, and dissolved Li source formed a closely structured matrix. LTO/C is comprised of crystalline LTO covered by a thin carbon layer. The RF resin plays an essential role in producing a suitable reaction field, preventing grain growth, and controlling the LTO primary particle size. The specific capacities of the LTO/C composite (carbon 15 wt%, carbonized at 900 °C) are 161 and 90 mAh/g at 0.1C and 25C, respectively. The composite shows improved electrochemical properties compared to commercial LTO.

Lithium ion conducting solid polymer blend electrolytes (SPBE) are prepared using the host polymers poly[vinylalcohol] (PVA), poly[vinyl pyrrolidone] (PVP) and the lithium acetate. The complexation between the polymers and salt is confirmed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The glass transition temperature of the prepared polymer electrolytes is determined by differential scanning calorimeter. Surface morphology of the polymer electrolytes is identified by scanning electron microscopy. Ionic conductivity of the solid electrolytes is studied using impedance analyzer in the frequency range of 42 Hz–1 MHz. The higher electrical conductivity of 5.79 × 10−6 S cm−1 and 1.400 × 10−4 S cm−1 is determined for 50PVA:50PVP:25 wt% lithium acetate system at 303 K and 363 K temperature, respectively. The dielectric and loss tangent analysis is also carried out for prepared polymer electrolyte and the higher-conductivity sample at different temperatures. The transference numbers of polymer electrolytes are calculated by Wagner’s polarizing technique and also confirmed by Bruce–Vincent technique.

Novel solid polymer electrolyte (SPE) films based on poly(methyl methacrylate) (PMMA) and lithium acetate (CH3COOLi) with different weight ratios of PMMA:CH3COOLi wt% (60:40, 70:30, 80:20 wt%) were prepared by solution casting technique. XRD analysis confirmed the amorphous nature of Li–PMMA SPE films. FTIR analysis revealed the structural changes in polymer by complexation with Li salt. From the optical absorbance studies, the value of lowest energy band gap was found to be 3.06 eV for the composition, PMMA:CH3COOLi (60:40 wt%). From AC impedance studies, the highest value of ionic conductivity 8.21 × 10−5 S/cm at 303 K for the SPE film PMMA:CH3COOLi (60:40 wt%) is observed compared to the reported literature. From the results of Li–PMMA SPE film with high ionic conductivity, it is a promising material for the application of solid-state battery.

The synthesis and study the effect of Al-doped on the electrochemical performance of Li4Ti5O12 (LTO) have been investigated. LTO as anode material was fabricated using Lithium acetate (C3H3O2Li), Tetrabutyl titanate atau TBT (C16H36O4Ti), Hidrocloric acid (HCl) 37%, ethanol (C2H5OH) and Alumunium Acetate (CH3CO2)3 via sol-gel route. Al atom here is used to support Ti atoms in accordance with the Li4Ti(5-x)AlxO12 stoicimetry equation. There are four variations of the doping composition (x) of aluminum such as x=0, 0.01, 0.02, and 0.03. All raw materials were stoichiometrically mixed and dried at 80°C for 24 hours and crushed to become precursors of LTO and Al-doped LTO. The precursors were sintered by using high temperature furmace at 850°C for 2 hours in air atmosphere. The final product was characterized by X-ray Diffraction (XRD) to determined crystal structure and phases. The products were also characterized by Scanning Electron Microscope (SEM) to determine the sample morphology and the average particle size distribution. The electrode sheets were prepared by mixing active material powdwers with PVDF and Super P in ratio 80: 10: 10 wt%. The slurry was coated on Cu foil with doctor blade method and dried at 80 °C for 30 minutes. The electrodes were cut into circular discs with 16 mm in diameter. The electrodes were arrangged with separator, metalic lithium and electrolyte become coin cell in a glove box. Automatic battery cycler was used to measure electrochemical performances and specific capacity of the cell. The XRD analysis showed that there are three main phases such as lithium titanium oxide (Li4Ti5O12/LTO), rutile phase (TiO2) and dilithium titanate (Li2TiO3). The SEM analysis showed that the surface of each sample has a different particle size which indicates that there is still agglomeration.Cyclic voltametry analysis showed that sample with Al-doped LTO 0.03 has the highest diffusion coefficient value of 7.31 x 10−10 S/cm2, while the sample without doping has the lowest diffusion coefficient of 3.27 x 10 −10 S/cm2. Charge discharge test showed that sample without doping has higher specific capacity than other samples with 181 mAh/g. The higher Al doping has the lower specific capacity of the battery.

Highlights A green water-in-salt electrolyte was developed using lithium acetate as solute with a wide electrochemical stability window of 2.8 V.Molecular dynamics simulation confirmed the nature of water-in-salt electrolyte, where hydrogen bonds of water–water were disrupted and ionic interactions became stronger than dilute solution.Nb18W16O93-based lithium-ion capacitors delivered unexceptionable stability over 50,000 cycles. Electronic supplementary material The online version of this article (10.1007/s40820-020-00508-z) contains supplementary material, which is available to authorized users., Aqueous hybrid supercapacitors are attracting increasing attention due to their potential low cost, high safety and eco-friendliness. However, the narrow operating potential window of aqueous electrolyte and the lack of suitable negative electrode materials seriously hinder its future applications. Here, we explore high concentrated lithium acetate with high ionic conductivity of 65.5 mS cm−1 as a green “water-in-salt” electrolyte, providing wide voltage window up to 2.8 V. It facilitates the reversible function of niobium tungsten oxide, Nb18W16O93, that otherwise only operations in organic electrolytes previously. The Nb18W16O93 with lithium-ion intercalation pseudocapacitive behavior exhibits excellent rate performance, high areal capacity, and ultra-long cycling stability. An aqueous lithium-ion hybrid capacitor is developed by using Nb18W16O93 as negative electrode combined with graphene as positive electrode in lithium acetate-based “water-in-salt” electrolyte, delivering a high energy density of 41.9 W kg−1, high power density of 20,000 W kg−1 and unexceptionable stability of 50,000 cycles. Electronic supplementary material The online version of this article (10.1007/s40820-020-00508-z) contains supplementary material, which is available to authorized users.

LiCoO2 has been synthesised by one step hydrothermal method using lithium acetate, cobalt acetate, sodium hydroxide and hydrogen peroxide as precursors. The hydrogen peroxide is used as oxidant in the reaction. The formation of LiCoO2 has been confirmed by X-ray Diffraction, UV/Vis and FTIR spectroscopy. The average crystallite size (D) and tensile strain (e) is calculated from XRD spectra. The optical parameters have been calculated from the absorption spectra of LiCoO2. The internal bending and stretching of LiCoO2 has been studied by FTIR spectroscopy. Electrochemical performance is studied by cyclic Voltammetry and impedance analyzer.

Hybrid anodes with Li4Ti5O12 nanoparticles uniformly embedding in a mesoporous activated carbon matrix are prepared by CO2 activation of copolymerized resorcinol and hexamethylenetetramine loaded by lithium acetate and tetrabutyl titanate. The Li4Ti5O12/activated-carbon hybrid anodes show increased capacity retention as the activated carbon content in the composite increases, although their overall specific capacity decreases gradually. The hybrid anode with an activated-carbon content of 54 wt% exhibits the highest capacity retention of 67% at 4 A g−1 referencing to that at 0.1 A g−1. When coupling it with commercial AC cathode, the Li-ion capacitor displays an outstanding high energy density of 38 Wh kg−1 even at a high power density of 7964 W kg−1. Moreover, an energy density retention of 90.8% after 2000 cycles at 1 A g−1 is preserved, demonstrating its very stable cycle performance. The results reported in this work indicate that the Li4Ti5O12/activated-carbon hybrids prepared by the proposed copolymerization and post-activation process may be very promising anode materials of Li-ion capacitors designed for high power applications.