• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.2
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• pp.89-95
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• 2021

Research on the production of lithium hydroxide (LiOH) has been actively conducted in response to the increasing demand for high nickel-based positive electrode materials for lithium-ion batteries. Herein we studied the conversion of lithium oxide (Li2O) through thermal decomposition of lithium carbonate for the production of lithium hydroxide from lithium carbonate (Li2CO3). The reaction mechanism of lithium carbonate with alumina, quartz and graphite crucible during heat treatment was confirmed. When graphite crucible was used, complete lithium oxide powder was obtained. Based on the TG analysis results, reagent-grade lithium carbonate was heat-treated at 700℃, 900℃ and 1100℃ for various time and atmosphere conditions. XRD analysis showed the produced lithium oxide showed high crystallinity at 1100℃ for 1 hour in a nitrogen atmosphere. In addition, several reagent-grade lithium oxides were reacted at 100℃ to convert to lithium hydroxide. XRD analysis confirmed that lithium hydroxide (LiOH) and lithium hydroxide monohydrate (LiOH·H2O) were produced.

• Clean Technology
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• v.19 no.4
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• pp.446-452
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• 2013

In this paper, the wet mixing method was introduced to prepare spinel lithium manganese oxide (LMO) with $Li_2CO_3$ and $MnCO_3$. The physical properties of the resulting lithium manganese oxide were characterized by the XRD and SEM. The adsorption properties of LMO for $Li^+$ were investigated by batch methods. The maximum adsorption capacity of lithium was calculated from Langmuir isotherm and found to be 27.25 mg/g. The LMO are found to have a remarkable lithium ion-sieve property with distribution coefficients ($K_d$) in the order of $Ca^{2+}$ < $K^+$ < $Na^+$ < $Mg^{2+}$ < $Li^+$, which is promising in the lithium extraction from seawater.

• Carbon letters
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• v.28
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• pp.87-95
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• 2018

This study examined the influence of operating parameters on the electrosorptive recovery system of lithium ions from aqueous solutions using a spinel-type lithium manganese oxide adsorbent electrode and investigated the electrosorption kinetics and isotherms. The results revealed that the electrosorption data of lithium ions from the lithium containing aqueous solution were well-fitted to the Langmuir isotherm at electrical potentials lower than -0.4 V and to the Freundlich isotherm at electrical potentials higher than -0.4 V. This result may due to the formation of a thicker electrical double layer on the surface of the electrode at higher electrical potentials. The results showed that the electrosorption reached equilibrium within 200 min under an electrical potential of -1.0 V, and the pseudo-second-order kinetic model was correlated with the experimental data. Moreover, the adsorption of lithium ions was dependent on pH and temperature, and the results indicate that higher pH values and lower temperatures are more suitable for the electrosorptive adsorption of lithium ions from aqueous solutions. Thermodynamic results showed that the calculated activation energy of $22.61kJ\;mol^{-1}$ during the electrosorption of lithium ions onto the adsorbent electrode was primarily controlled by a physical adsorption process. The recovery of adsorbed lithium ions from the adsorbent electrode reached the desorption equilibrium within 200 min under reverse electrical potential of 3.5 V.

• Journal of Environmental Science International
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• v.24 no.5
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• pp.641-646
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• 2015

In order to recover lithium ions from aqueous solution, a novel SAN-LMO beads were prepared by immobilizing lithium manganese oxide (LMO) with styrene acrylonitrile copolymers (SAN). The optimum condition for synthesis of SAN-LMO beads was 5 g of LMO and 3 g of SAN content. The characterization of the prepared SAN-LMO beads by SEM and XRD were confirmed that LMO was immobilized in SAN-LMO beads. The removal and the distribution coefficient of lithium ions decreased with increasing lithium ion concentration and solution pH. Even when the prepared SAN-LMO beads were reused 5 times, the leakage of LMO and the damage of SAN-LMO beads was not observed.

• 한국전기화학회:학술대회논문집
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• 2001.11a
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• pp.75-93
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• 2001

• Journal of the Korean Electrochemical Society
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• v.12 no.3
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• pp.251-257
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• 2009

In this study, we fabricated nickel oxide thin film for lithium based electrolyte using sol-gel method. This film was deposited by dip-coating method with mixed solvent of DameH (N,N-dimethylaminoethanol) and DI water. As changing the ratio between DmaeH and DI water, nickel oxide thin film was presented in different charge density and optical transmittance because they were shown various thickness. It was accounted for changing viscosity and density by the ratio of DmaeH and DI water. The thin film synthesized with 1 : 1 ratio of DmaeH and DI water was expressed best electrochromic performance in lithium based electrolyte, because of thick thickness but porous structures.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3183-3189
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• 2010

In order to increase the specific capacitance and energy density of supercapacitors, non-aqueous supercapacitors were prepared using lithium transition-metal oxides and activated carbons as active materials. The electrochemical properties were analyzed in terms of the content of lithium transition-metal oxides. The results of cyclic voltammetry and AC-impedance analyses showed that the pseudocapacitance may stem from the synergistic contributions of capacitive and faradic effects; the former is due to the electric double layer which is prepared in the interface of activated carbon and organic electrolyte, and the latter is due to the intercalation of lithium ($Li^+$) ions. The specific capacitance and energy density of a supercapacitor improved as the lithium transition-metal oxides content increased, showing 60% increase compared to those of supercapacitor using a pure activated carbon positive electrode.

• Korean Journal of Materials Research
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• v.21 no.1
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• pp.21-27
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• 2011

A nano-porous structure of tin oxide was prepared using an anodic oxidation process and the sample's electrochemical properties were evaluated for application as an anode in a rechargeable lithium battery. Microscopic images of the as-anodized sample indicated that it has a nano-porous structure with an average pore size of several tens of nanometers and a pore wall size of about 10 nanometers; the structural/compositional analyses proved that it is amorphous stannous oxide (SnO). The powder form of the as-anodized specimen was satisfactorily lithiated and delithiated as the anode in a lithium battery. Furthermore, it showed high initial reversible capacity and superior rate performance when compared to previous fabrication attempts. Its excellent electrode performance is probably due to the effective alleviation of strain arising from a cycling-induced large volume change and the short diffusion length of lithium through the nano-structured sample. To further enhance the rate performance, the attempt was made to create porous tin oxide film on copper substrate by anodizing the electrodeposited tin. Nevertheless, the full anodization of tin film on a copper substrate led to the mechanical disintegration of the anodic tin oxide, due most likely to the vigorous gas evolution and the surface oxidation of copper substrate. The adhesion of anodic tin oxide to the substrate, together with the initial reversibility and cycling stability, needs to be further improved for its application to high-power electrode materials in lithium batteries.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.3
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• pp.119-123
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• 2005

Lithium titanium oxide as anode material for energy storage prepared by novel synthesis method. Li$_{4}$Ti$_{5}$O$_{12}$ based spinel-framework structures are of great interest material for lithium-ion batteries. We describe here Li$_{4}$Ti$_{5}$O$_{12}$ a zero-strain insertion material was prepared by novel sol-gel method and by high energy ball milling (HEBM) of precursor to from nanocrystalline phases. According to the X-ray diffraction and scanning electron microscopy analysis, uniformly distributed Li$_{4}$ Ti$_{5}$O$_{12}$ particles with grain sizes of 100nm were synthesized. Lithium cells, consisting of Li$_{4}$ Ti$_{5}$O$_{12}$ anode and lithium cathode showed the 173 mAh/g in the range of 1.0 $\~$ 3.0 V. Furthermore, the crystalline structure of Li$_{4}$ Ti$_{5}$O$_{12}$ didn't transform during the lithium intercalation and deintercalation process.

• Journal of Electrochemical Science and Technology
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• v.7 no.3
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• pp.206-213
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• 2016

Transition metal oxide-based electrodes for lithium ion batteries have recently attracted much attention because of their high theoretical capacity. Here we report the electrochemical behavior of cobalt oxide nanorods as anodes, prepared by a template-free, one-step electrochemical deposition of cobalt nanorods, followed by an oxidation process. The as-deposited cobalt has a slightly convex columnar structure, and controlled thermal oxidation produces cobalt oxides of different Co/O ratios, while the original shape is largely preserved. As an anode in a rechargeable lithium battery, the Co/O ratio has a strong effect on initial capacity and cycling stability. In particular, the one-dimensional Co@Co_xO_y core shell structure obtained from a mild heat-treatment results in superior cycling stability.