• Title, Summary, Keyword: Electrochemical Impedance Spectroscopy (EIS)

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New Analysis of Electrochemical Impedance Spectroscopy for Lithium-ion Batteries

  • Osaka, Tetsuya;Nara, Hiroki;Mukoyama, Daikichi;Yokoshima, Tokihiko
    • Journal of Electrochemical Science and Technology
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    • v.4 no.4
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    • pp.157-162
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    • 2013
  • First of all, we express our deepest sympathies for the passing of Professor Su-Moon Park. In the present paper, an electrochemical impedance spectroscopy (EIS), which Professor Su-Moon Park also used frequently for the investigation of electroconducting polymer, is introduced as a recent evaluation tool for a commercially available lithium-ion battery (LIB). The paper surveys how to design equivalent circuits while explaining physical and chemical phenomena in the LIB and how to get more accurate impedance spectra with varying the measuring temperatures. Additionally, a square current EIS (SC-EIS) technique, which we have suggested, is introduced for the larger LIB system as a promising technique for the future.

On eliminating electrochemical impedance signal noise using Li metal in a non-aqueous electrolyte for Li ion secondary batteries

  • Park, Chul-Wan
    • Carbon letters
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    • v.12 no.3
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    • pp.180-183
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    • 2011
  • Li metal is accepted as a good counter electrode for electrochemical impedance spectroscopy (EIS) as the active material in Li-ion and Li-ion polymer batteries. We examined the existence of signal noise from a Li-metal counter quantitatively as a preliminary study. We suggest an electrochemical cell with one switchable electrode to obtain the exact impedance signal of active materials. To verify the effectiveness of the switchable electrode, EIS measurements of the solid electrolyte interphase (SEI) before severe $Li^+$ intercalation to SFG6 graphite (at > ca. 0.25 V vs. Li/$Li^+$) were taken. As a result, the EIS spectra without the signal of Li metal were obtained and analyzed successfully for the following parameters i) $Li^+$ conduction in the electrolyte, ii) the geometric resistance and constant phase element of the electrode (insensitive to the voltage), iii) the interfacial behavior of the SEI related to the $Li^+$ transfer and residence throughout the near-surface (sensitive to voltage), and iv) the term reflecting the differential limiting capacitance of $Li^+$ in the graphite lattice.

Studies on the Concrete Reinforcement Corrosion by Electrochemical Impedance Spectroscopy (전기화학적 임피던스법에 의한 철근콘크리트의 부식연구)

  • Kang, Tae-Hyuk;Cho, Won-Il;Cho, Byung-Won;Ju, Jeh-Beck;Yun, Kyung-Suk
    • Applied Chemistry for Engineering
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    • v.9 no.6
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    • pp.907-913
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    • 1998
  • Corrosion behavior of steel reinforcements embedded in concrete containing various chloride ion concentrations was investigated by an electrochemical impedance spectroscopy(EIS). Chloride ions were introduced into the concrete by dissolving the NaCl and $CaCl_2$ in the water with a given weight of cement. Based on the impedance parameters measured by EIS, more complete equivalent circuit, a schematic physical model, and the mechanism of concrete reinforcement corrosion were suggested. By the implement of experimental impedance parameters obtained from the model with corresponding CNLS-fitting data, the corrosion rate of steel reinforcement with chloride ions could be predicted.

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Properties Investigation of Corrosion Monitoring for Pure Mg Thin Films under Wet-Dry Cyclic Conditions by Using Electrochemical Impedance Spectroscopy Method (건습환경중 순 Mg박막의 EIS부식 모니터링 특성 관찰)

  • Bae, I.Y.;Lee, K.H.;Kim, K.J.;Moon, K.M.;Lee, M.H.
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • pp.192-193
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    • 2005
  • Magnesium thin films were prepared on cold-rolled steel substrates by RF(Radio Frequency) magnetron sputtering technique.$^{1)}$ The crystal orientation and monitoring of the deposited films were investigated by using XRD(X-ray Diffraction) and EIS(Electrochemical Impedance Spectroscopy), respectively. The corrosion rates of Mg thin films deposited with different argon gas pressure and substrate bias voltage were monitored by AC impedance method under a cyclic wet-dry condition, which was conducted by exposure to alternate conditions of 1h immersion in 3%NaCl solution and 5h drying at 60% RH and 25$^{\circ}C$. The result of corrosion rate of Mg thin films deposited at various Ar gas pressures and substrate bias voltage under wet-dry cyclic exposure in chloride-containing solutions was showed the following conclusions. At the region I during the onset of the wet cycle, corrosion rate showed relatively low value. The increase in the Corrosion rate of region II is due to the increase in the chloride concentration. Corrosion rate of region III during the onset of the cycle zero and salt crystals remain on the metal surface.$^{2)}$

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Anodization of Aluminium Samples in Boric Acid Solutions by Optical Interferometry Techniques

  • Habib, K.
    • Corrosion Science and Technology
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    • v.4 no.6
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    • pp.217-221
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    • 2005
  • In the present investigation, holographic interferometry was utilized for the first time to monitor in situ the thickness of the oxide film of aluminium samples during anodization processes in boric acid solutions. The anodization process (oxidation) of the aluminium samples was carried out by the technique of the electrochemical impedance spectroscopy(EIS), in different concentrations of boric acid (0.5-5.0% $H_3BO_3$) at room temperature. In the mean time, the real-time holographic interferometry was used to measure the thickness of anodized (oxide) film of the aluminium samples in solutions. Consequently, holographic interferometry is found very useful for surface finish industries especially for monitoring the early stage of anodization processes of metals, in which the thickness of the anodized film of the aluminium samples can be determined without any physical contact. In addition, measurements of electrochemical values such as the alternating current (A.C) impedance(Z), the double layer capacitance($C_{dl}$), and the polarization resistance(Rp) of anodized films of aluminium samples in boric acid solutions were made by the electrochemical impedance spectroscopy(EIS). Attempts to measure electrochemical values of Z, Cdl, and Rp were not possible by holographic interferometry in boric acid especially in low concentrations of the acid. This is because of the high rate of evolutions of interferometric fringes during the anodization process of the aluminium samples in boric acid, which made measurements of Z, Cdl, and Rp are difficult.

Modeling and Applications of Electrochemical Impedance Spectroscopy (EIS) for Lithium-ion Batteries

  • Choi, Woosung;Shin, Heon-Cheol;Kim, Ji Man;Choi, Jae-Young;Yoon, Won-Sub
    • Journal of Electrochemical Science and Technology
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    • v.11 no.1
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    • pp.1-13
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    • 2020
  • As research on secondary batteries becomes important, interest in analytical methods to examine the condition of secondary batteries is also increasing. Among these methods, the electrochemical impedance spectroscopy (EIS) method is one of the most attractive diagnostic techniques due to its convenience, quickness, accuracy, and low cost. However, since the obtained spectra are complicated signals representing several impedance elements, it is necessary to understand the whole electrochemical environment for a meaningful analysis. Based on the understanding of the whole system, the circuit elements constituting the cell can be obtained through construction of a physically sound circuit model. Therefore, this mini-review will explain how to construct a physically sound circuit model according to the characteristics of the battery cell system and then introduce the relationship between the obtained resistances of the bulk (Rb), charge transfer reaction (Rct), interface layer (RSEI), diffusion process (W) and battery characteristics, such as the state of charge (SOC), temperature, and state of health (SOH).

Corrosion Prediction of Metallic Cultural Heritage Assets by EIS

  • Angelini, E.;Grassini, S.;Parvis, M.;Zucchi, F.
    • Corrosion Science and Technology
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    • v.18 no.4
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    • pp.121-128
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    • 2019
  • Electrochemical Impedance Spectroscopy (EIS) was used to predict corrosion behaviour of metallic Cultural Heritage assets in two monitoring campaigns: 1) an iron bar chain exposed indoor from over 500 years in the Notre Dame Cathedral in Amiens (France); and 2) a large weathering steel sculpture exposed outdoor from tens of years in Ferrara (Italy). The EIS portable instrument employed was battery operated. In situ EIS measurements on the iron chain could be used to investigate the phenomena involved in the electrochemical interfaces among various corrosion products and assess and predict their corrosion behaviour in different areas of the Cathedral. Meanwhile, the sculpture of weathering steel, like most outdoor artefacts, showed rust layers of different chemical composition and colour depending on the orientation of metal plates. The EIS monitoring campaign was carried out on different areas of the artefact surface, allowing assessment of their protective effectiveness. Results of EIS measurements evidenced how employing a simple test that could be performed in situ without damaging the artefacts surface is possible to quickly gain knowledge of the conservation state of an artefact and highlight potential danger conditions.

Electrochemical Impedance Spectroscopy and Cyclic Voltammetry Methods for Monitoring SmCl3 Concentration in Molten Eutectic LiCl-KCl

  • Shaltry, Michael R.;Allahar, Kerry N.;Butt, Darryl P.;Simpson, Michael F.;Phongikaroon, Supathorn
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.1
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    • pp.1-18
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    • 2020
  • Molten salt solutions consisting of eutectic LiCl-KCl and concentrations of samarium chloride (0.5 to 3.0 wt%) at 500℃ were analyzed using both cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The CV technique gave the average diffusion coefficient for Sm3+ over the concentration range. Equipped with Sm3+ diffusion coefficient, the Randles-Sevcik equation predicted Sm3+ concentration values that agree with the given experimental values. From CV measurements; the anodic, cathodic, and half-peak potentials were identified and subsequently used as a parameter to acquire EIS spectra. A six-element Voigt model was used to model the EIS data in terms of resistance-time constant pairs. The lowest resistances were observed at the half-peak potential with the associated resistance-time constant pairs characterizing the reversible reaction between Sm3+ and Sm2+. By extrapolation, the Voigt model estimated the polarization resistance and established a polarization resistance-concentration relationship.

A Experimental Study on the Evaluation of Anti-corrosion Performance of rebar in concrete added chloride and inhibitor using EIS method (EIS를 이용한 염화물 및 방청제가 첨가된 콘크리트에 매립된 철근의 방식성능 평가에 관한 실험적 연구)

  • Park, Jang-Hyun;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • pp.134-135
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    • 2016
  • To evaluate anti-corrosion performance of rebar in concrete according to the amount of chloride and inhibitor, electrochemical impedance spectroscopy(EIS) method was conducted in this study. For the anti-corrosion performance evaluation according to time, Impedance of rebar in concrete was measured before and after 5 cycle of corrosion acceleration. As a results, The impedance of rebar in concrete added chloride decreased than before corrosion acceleration. However impedance of other specimens was maintained or increased than before corrosion acceleration.

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An Experimental Study on the Corrosion Behavior of Rebar in Cement Mortar by Using EIS Method (EIS를 이용한 시멘트 모르타르에 매입된 철근의 부식거동에 관한 실험적 연구)

  • Park, Jang-Hyun;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • pp.145-146
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    • 2016
  • In this study, Corrosion behavior in mortar was observed by the passage of time by using EIS method. As a result of EIS experiment, equivalent circuit and changes of Impedance parameter could be observed. In addition, it was confirmed that impedance of rebar in mortar and corrosion rate according to the amount of NaCl were different.

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