bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterizing Coupled Transport Phenomena in Large-Format Lithium-Ion Pouch Cells Using Lock-in Thermography and Laser Scanning
Authors: Chu Howie , Monroe Charles W. 
Published: December 2020

Management of battery systems is difficult due to the variety of physical processes that occur when a battery is put under an electrical load. These processes produce macroscopic side effects, such as stress/strain and temperature evolution, which originate at the electrode level. The electrochemical-thermal-mechanical phenomena in battery cells are highly coupled in applications such as electric vehicles. Because microscopic effects in battery electrodes can propagate into larger length scales such as the cell and pack levels, there are changes on the outside that can be observed.
Contact-free, non-destructive methods for measuring changes in battery temperature and strain could serve as tools to determine a battery’s second-life prospects, and could also aid early fault detection. The lock-in thermography technique has been used to determine faults and locate defects within cells.1 It has also been shown that mechanical stresses can be used to monitor state of health (SOH) and state of charge (SOC).2,3 Laser scanning has also been implemented to generate strain distributions showing local mechanical effects during electrochemical cycling.4

A first step in understanding highly coupled systems is to characterize the individual phenomena in isolation. Figure 1 presents a contour plot that shows the result of a zero-displacement experiment, where the evolution of equilibrium stress within a constrained 3-cell battery pack is measured at various SOCs and at various ambient temperatures. This experiment has shown that thermally induced volume change can contribute as much to mechanical forces within a cell as intercalation/deintercalation stresses. In high-power applications such as electric vehicles, we expect to see consequences from both of these factors. So, we will be developing an experimental set-up that combines the techniques of lock-in thermography and laser scanning to simultaneously capture 2D strain and temperature distributions that arise in response to different current input signals. Data from the individual techniques, plus the combined experiment, can be used to see how a battery’s response changes as a consequence of its thermal and mechanical state, and how the relative contributions of temperature and strain can affect battery operation.
References

Robinson, J. B. et al. Detection of Internal Defects in Lithium-Ion Batteries Using Lock-in Thermography. ECS Electrochem. Lett.
4, A106–A109 (2015).

Cannarella, J. & Arnold, C. B. State of health and charge measurements in lithium-ion batteries using mechanical stress. J. Power Sources
269, 7–14 (2014).

Mohtat, P., Lee, S., Siegel, J. B. & Stefanopoulou, A. G. Towards better estimability of electrode-specific state of health: Decoding the cell expansion. J. Power Sources
427, 101–111 (2019).

Rieger, B. et al. Multi-directional laser scanning as innovative method to detect local cell damage during fast charging of lithium-ion cells. J. Energy Storage
8, 1–5 (2016).

Figure 1
Microstructure Modified Ni-Rich Cathode Material By Microscale Concentration Gradient for High Energy Density Li-Ion Batteries
Authors: Kim Un-Hyuck , Sun Yang-Kook 
Published: December 2020

A concentration gradient (CG) Li[Ni0.9Co0.05Mn0.05]O2 cathode in which Li[Ni0.94Co0.038Mn0.022]O2 at the particle core is encapsulated by a 1.5-μm-thick CG shell with the outer surface composition Li[Ni0.841Co0.077Mn0.082]O2 is synthesized using a differential co-precipitation process. The CG at the microscale combined with the radial texturing of the refined primary particles in the CG shell layer protracts the detrimental H2 → H3 phase transition1,2, providing with the rise to sharp changes in the unit cell dimensions. This protraction, confirmed by in-situ X-ray diffraction and transmission electron microscopy, allows effective dissipation of the internal strain generated upon the H2 → H3 phase transition, markedly improving cycling performance and thermochemical stability as compared to those of the conventional without CG Li[Ni0.9Co0.05Mn0.05]O2 cathode3-6. The compositionally partitioned cathode delivers a specific capacity of 229 mAh g-1 and exhibits capacity retentions of 88% after 1,000 cycles in a pouch-type full cell (cf. 68% for the conventional cathode). Thus, the proposed cathode material provides an opportunity for the rational design and development of a wide range of multi-functional cathodes, especially for Ni-rich NCM cathodes, by compositionally partitioning the cathode particles and thus optimizing the microstructural response to the internal strain produced in the 100% depth of discharge state.
Reference

U.-H. Kim, S.-T. Myung, C. S. Yoon and Y.-K. Sun ACS Energy Lett.
2017, 2, 1848-1854.

H.-H. Ryu, K.-J. Park, C. S. Yoon and Y.-K. Sun Chem. Mater.
2018, 30, 1155.

Y.-K. Sun, S.-T. Myung, B.-C. Park, J. Prakash, I. Belharouak and K. Amine. Nat. Mater.
2009, 8, 320.

U.‐H. Kim, E.‐J. Lee, C. S. Yoon, S.‐T. Myung and Yang‐Kook Sun Adv. Energy Mater.
2016, 6, 1601417.

D.-W. Jun, C. S. Yoon, U.-H. Kim and Y.-K. Sun Chem. Mater.
2017, 29, 5048.

U.-H. Kim, S.-T. Myung, C. S. Yoon and Yang-Kook Sun ACS Energy Lett.
2017, 2, 1848.
(Invited) Elucidating the Role of Mo during the Passivation of Ni-Cr-Mo Alloys: Real Time Analysis of Elemental Dissolution and Surface Enrichment
Authors: Li Xuejie , Henderson Jeffrey D. , Shoesmith David W. , Noel James , Ogle Kevin 
Published: December 2020

Molybdenum is a common alloying element used in Ni-Cr and Fe-Cr alloys to improve their passive properties. Despite its ubiquity, the precise role Mo plays during passivation remains poorly understood. Recently we have investigated the role of Mo in commercial allows during both passive film formation [1] in acidic solution and during transpassive dissolution and repassivation in neutral chloride solution [2] using atomic emission spectroelectrochemistry (AESEC). In this work we refine the conclusions of the previous studies by working with pure binary and ternary alloys, Ni22Cr wt.% and Ni22Cr10Mo wt.%, the simplicity of which permits a clearer picture of the underlying mechanisms. The dissolution rates of Ni, Cr, and Mo and the surface enrichments of Cr and Mo were determined as a function of time during electrochemical experiments and film composition and oxidation state information was obtained by X-ray photoelectron spectroscopy (XPS). For both alloys, following cathodic removal of the passive film (activation), a spontaneous open circuit passivation was observed at ≈-0.25 V vs. SCE which involved the enrichment of both Cr and Mo. Stepping the potential further into the passive domain (+0.3 V vs. SCE) lead to a further enhancement of the Cr enrichment but a partial dissolution of the Mo enrichment.
The XPS results suggest that Mo dissolution may be attributed to the oxidation of the less soluble Mo(IV) to more soluble Mo(VI) species as suggested in our previous work with a commercial Ni alloy [1]. The suggestion is that Mo enriches on the surface only during a certain domain of potential and this suggests the hypothesis that Mo facilitates the initial growth of the passive film.

“The Passivation of Ni-Cr-Mo Alloys: Time Resolved Enrichment and Dissolution of Cr and Mo during Passive-Active Cycles”, X Li, K Ogle, J. Electrochem. Soc. 166 (2019)C3179-C3185.

“Molybdenum surface enrichment and release during transpassive dissolution of Ni-based alloys”, JD Henderson, X Li, DW Shoesmith, JJ Noël, K Ogle, Corrosion Science 147(2019)32-40

Figure 1
(Invited) Innovative 3D-Printed Flow-Type Electrochemical Microcell for Ultra-High Spatial Resolution Electrochemistry
Authors: Summers Kodi , Chidambaram Dev 
Published: December 2020

Advances in 3D-printing technology have been used to design and develop a customizable flow-type electrochemical microcell that provides analytical resolution comparable to that of conventional glass capillary-based electrochemical microcells. In addition to being highly reproducible compared to the fabrication of glass capillaries, the advantages of this design are increased durability, decreased production costs, and better control over design parameters while maintaining ultra-high spatial resolution. The design is a three-component microcell that combines 3D printing with conventional machining to allow rapid prototyping and testing of flow designs and apertures sizes while maintaining a consistent foundation upon which the design can be built. The key benefit of the three-component design is the ability to replace parts as needed without complete disassembly. The design and application of two classes of flow-type electrochemical microcell, high-resolution (~100 µm spot size) and ultra-high resolution (~10 µm spot size), will be presented. Additionally, the proposed prototype introduces the practicality of a six-axis robot arm for positioning the microcell and is advantageous over a conventional three-axis gantry system allowing for the analysis of irregular sample geometries. The microcell prototype was tested and evaluated to demonstrate repeatability in use, accuracy in spatial resolution and experimental results, and capability in the analysis of various materials and surface finishes. The ease of use and endurance of the design is also demonstrated through repeated use. This microcell has the potential for applications in corrosion, electrodeposition, and electroanalysis, amongst others.
Acknowledgements: This work was supported by the United States Nuclear Regulatory Commission (NRC) under contract NRC-HQ-84-16-G-0033. Ms. Nancy Hebron-Israel serves as the program manager.
(Invited) In Situ Observation of Anomalous Hydrogen Evolution on Mg Under Anodic Polarization
Authors: Chu Peng-Wei , Su Yu-You 
Published: December 2020

Mg alloys have long been considered a promising lightweight alloy system for various applications including consumer electronics, transportation, and medical equipment. However, owing to their high reactivity, Mg alloys cannot be used without proper coatings or surface treatments. Nevertheless, the chemical reactivity of Mg also opens up new ideas, such as the development of Mg-based biodegradable body implants and Mg metal battery systems. Unlike other metallic elements, Mg possesses a unique electrochemical response, especially under anodic polarization. To be specific, the rate of water reduction and hydrogen gas evolution, which is the dominant cathodic reaction on Mg in aqueous solutions, opposingly accelerates with the increase in anodic polarization. This phenomenon is the notorious negative difference effect (NDE) of Mg, or recently coined as the “anomalous hydrogen evolution”. Even after decades of research, the underlying mechanism of this peculiar electrochemical response of Mg is still under debate and yet to be elucidated.
In order to have a clear picture of how the anomalous hydrogen evolution is related to the dissolution of Mg under anodic polarization, a customized cell was designed to enable high resolution in situ observation of the hydrogen evolution sites and surface morphology on Mg with an optical microscope. The compact cell is small enough to fit under the optical microscope with a short working distance at high magnification (50x-500x). The cell and the equipped reference and counter electrodes are connected to a potentiostat/galvanostat to control and monitor the polarization of the Mg working electrode. Additionally, a dynamic fluid control system is used to regulate the solution flow rate in the cell and constant circulation to avoid chemical or pH shifts. Additionally, the flowing solution also flushes away hydrogen bubbles attached to the electrode surface and ensure an unblocked view of the Mg surface. From this experimental setup, the anomalous hydrogen evolution under anodic polarization was found to be closely related to the actively propagating localized corrosion front of Mg. The relationship between hydrogen evolution response, applied anodic polarization, solution flow rate, as well as possible negative difference effect mechanisms, will be discussed.

Figure 1
(Invited) Surface Characterisation of Ni-Rich NMC Materials Stored in Various Environments
Authors: Guyomard Dominique , Laurita Angelica , Cabelguen Pierre Etienne , Zhu Liang , Dupré Nicolas , Fernandez Vincent , Hamon Jonathan , Moreau Philippe 
Published: December 2020

In order to obtain higher energy densities for electromobility applications, the market is now heading towards high-nickel content NMCs. However, these materials suffer from severe gassing issues decreasing the cycle life and causing safety problems. While it is agreed that the O2 evolution is coming from oxygen lattice oxidation at the end of charge, the source of CO and CO2 gassing is still under debate.
In this context, we report here a systematic study of NMC811 pristine material surface contaminations obtained after storage in different controlled environments. We use a multi-analytical approach involving combined MAS-NMR, XPS and STEM-EELS to provide a full material characterisation before cycling. The chemical environment of the Li present in the paramagnetic bulk of the material is successfully determined by means of 7Li MAS-NMR at low field (200 MHz). High field 7Li MAS-NMR (500 MHz) allows the quantification of the surface diamagnetic Li. Low field 1H MAS-NMR gives insights on the proton bulk and surface environments. STEM-EELS mapping is performed with both high energy and high spatial resolution using our new TEM/STEM Themis Z G3 (Thermo Fisher Scientific) equipped with a double camera GIF spectrometer. We obtain a good multi-elemental chemistry mapping quantification as well as the accurate analysis of the fine structure of the L3/L2 Ni edges thanks to the use of an excited monochromator.
Putting together all characterisation results, we achieved a thorough analysis of primary particles surface contamination after different controlled storage conditions, that will be correlated with gassing measurements and cell cycling stability.
Effect of Ni Content on the Initial Corrosion Resistance of Steel in Atmospheric Environment
Authors: Kiyoizumi Kota , Ono Yuichi , Katayama Hideki , Hoshi Yoshinao , Watanabe Hikari , Shitanda Isao , Itagaki Masayuki , Akashi Takaya , Satoh Hina , Nagasawa Makoto 
Published: December 2020

Weathering steels with a protective rust layer are well known to exhibit high corrosion resistance in mild corrosive environment for a long time even if it is used without paint. However, they do not generally show high corrosion performance in coastal area. Therefore, there have been numerous reports on the corrosion resistance and corrosion mechanism of weathering steel by exposure tests, electrochemical measurements, and rust analysis. However, the detailed effects of additive elements such as Ni and Cr on corrosion resistance have not been clarified. In this study, we focused on Ni as an additive element, and investigated the effect of Ni addition on the initial corrosion resistance of Fe-Ni alloy with different amounts of Ni by corrosion monitoring and electrochemical measurement under atmospheric corrosion environment. Fe (Fe : 99.7%), Fe-3mass% Ni, and Fe-5mass% Ni (Fe, 3Ni, and 5Ni) were used as the samples. The concentric ring type corrosion sensors (corrosion sensor) and the electrodes embedded in an epoxy resin were prepared for an atmospheric corrosion monitoring and for an electrochemical measurement, respectively. The wet and dry cyclic corrosion test was conducted in the chamber set at 25°C and 60% RH after adding 100 µL droplet of a 0.01 mol dm-3 NaCl solution. During the corrosion test, the atmospheric corrosion behavior was monitored by continuously measuring the impedance at low frequency (10 mHz) and high frequency (10 kHz) by a corrosion monitor. On the other hand, polarization curves were measured with a three-electrode system from the immersion potential. The scanning rate was set at 0.5 mV / s. In addition, the electrochemical impedance measurements were performed for the samples with and without passive film, in order to investigate the characteristic of the sample surface. The impedances were measured at 10mV of applied potential with the frequency range from 100 kHz to 10 mHz.
The corrosion rate of the steel content Ni in the first cycle was less than one-tenth that of Fe, and was almost the same for 3Ni and 5Ni. However, the corrosion rate after the second cycle decreased with increasing Ni content, and 5Ni showed a low value for a long time. This indicates that the Ni-content steel shows high corrosion resistance in the initial corrosion process. Almost the same oxygen diffusion limited current was observed in the cathodic polarization curves of all samples. On the other hand, the anodic currents of 3Ni and 5Ni, which are considered to correspond to the dissolution of Fe, were about one digit smaller than that of Fe. The impedance of Ni-content steels was larger than that of Fe. However, this result was not agreement with the corrosion monitoring results. Furthermore, the result of surface alalysis will be introduced in our poster.
Addition of an Eco-Friendly Corrosion Inhibitor in Self-Assembled Monolayers Coatings to Improve Pitting Corrosion Resistance of Stainless Steel
Authors: Rougier Agathe , Melot Jean Marie , Doche Marie-Laure , Touyeras Francis , Roizard Xavier , Lallemand Fabrice , Hihn Jean-Yves 
Published: December 2020

In automotive industry and equipment manufacturers, treatment by phosphatation [1] is used both as an adhesion primer before painting and as a lubricant coating [2]. This treatment also offers a good protection against corrosion. However, phosphatation is quite harmfull for the environment, producing a lot of waste to be treated. With regards to toxicity, it is composed of concentrated acids, nitrates and nitrites. Eventually, OEM are working to reduce the thickness of this coating which is typically in the range 2-30 μm. The objective of our research is to propose an alternative to steel/phosphate systems by thin organic coating on 304 stainless steel, a low carbon content substrate free of Molybdene available at affordable costs
To fit with the required specification while being as attractive as possible, this alternative coating must present a thickness reduced to a few nanometers, be environmentally friendly, non-toxic and easy to use. It must keep the main properties of phosphatation which consist in adhesion or anti-wear. Self-assembled Monolayers (SAMs) [3] coatings were chosen with addition of Aloe Vera as an ecological corrosion inhibitor [4][5]. SAMs are tunable by adjusting either their terminal group or the length of the carbon chain to obtain the desired surface properties and corrosion resistance. Three different terminal groups combined with four carbon chain lengths have been tested to find the molecule providing the best protection against corrosion.
An electrochemical study is carried out to quantify protection against pitting corrosion in a chloride-containing medium. The substrate used being a 304 stainless steel. As pitting corrosion mechanism involves both stable and unstable pits, two types of electrochemical methods are used. Pulsed potentials technic will highlighted unstable pits, while stable pits are analysed by cyclic voltammetry. These measurements are supported by surface analysis (SEM, EDS).
[1] T. W. COSLETT, Treatment of iron or steel for preventing oxidation or rusting, British patent 8667 and US patent 870937, 1906 et 1907
[2] J. BOGI, Phosphate conversion coatings on steel, J Mater Sci (1977) 12, 2235-2240
[3] A. ULMAN, Formation and structure of self-assembled monolayers, Chem. Rev. 1996, 96, 1533-1554
[4] Devarayan, Kesavan, Green Inhibitors for Corrosion of Metals: A Review, Chem Sci Rev Letts, (2012)
[5] M. MEHDIPOUR, Electrochemical noise investigation of Aloe plant extract as green inhibitor on the corrosion of stainless steel in 1M H2SO4, J. Ind. Eng. Chem, (2015), 21, 318-327

Figure 1
(Invited) Reaction and Failure Mechanisms of Layered Na1-XMO2 (M = Mn, Fe, Ni, and their solid solutions) As Cathode Materials for Sodium Ion Batteries
Authors: Lee Kyu Tae 
Published: December 2020

Sodium ion batteries have been considered one of the most promising large-scale energy storage systems for grid energy storage because of their potentially low cost. The current sodium ion batteries, however, have slightly lower energy density than lithium ion batteries, implying that the energy density limitations offset the cost savings. In this regard, it is demanded to develop high capacity cathode materials for improving the energy density of sodium ion batteries.
Various layered-structured sodium transition metal oxides have been extensively examined as high capacity cathode materials. Recently, there have been remarkable improvements in the electrochemical performances of layered oxide materials, although they still present challenges, such as poor structural stability and severe electrolyte decomposition, leading to capacity fading during long cycling. In this connection, doped- and coated-layered oxide materials have been investigated in an effort to improve structural and interfacial stability.
In this presentation, we introduce our recent works involving the reaction and failure mechanisms of layered Na1-xMO2 (M = Mn, Fe, Ni, and their solid solutions) cathode materials for sodium ion batteries. We demonstrate the role of dopants in the reaction mechanisms of layered oxide materials. Their failure modes, such as crack formation mechanism and cation disordering, are also discussed. Then, we suggest a strategy for improving the electrochemical performance of layered Na1-xMO2.
Effect of Petroleum Pitch-Coating on the Electrochemical Performance of Graphite As Anode Materials
Authors: Lee Jong Dae , Jo Yoon Ji 
Published: December 2020

Lithium ions batteries (LIBs) have become the most promising energy storage device in new energy field due to their potential utility as high-energy-density batteries for electric vehicles and hybrid electric vehicles. Graphite, which is the most widely commercialized anode material of LIBs, exhibits structural stability and excellent cycle characteristics. However, graphite has some problems to overcome. Due to the uneven SEI (Solid Electrolyte Interface) layer generated after the initial cycle, considerable irreversible capacity loss occurs. This results in electrode collapse and cycle instability especially in high-rate charging. Therefore, many researchers have been reported to improve the stability of graphite with carbon coating.
In this study, electrochemical characteristics of artificial graphite coated with petroleum pitch were investigated as anode materials of lithium ion batteries. To improve the capacity and stability of graphite, it was coated with petroleum pitch(SP, 150, 200 and 250 ℃). The physical properties of prepared samples were analyzed by MALDI-TOF, TGA, XRD, SEM and TEM. The electrochemical performances of graphite composites as an anode were evaluated by initial charge/discharge, cycle, rate performance, cyclic voltammetry and electrochemical impedance spectroscopy (EIS) tests. The electrolyte used in the half cell was 1.0 M LiPF6 dissolved in organic solvents (EC:DEC=1:1 vol%).
It was found that the pitch(SP 250 ℃) anode materials had excellent electrochemical characteristics: good initial efficiency (92.9%), discharge capacity (343 mAh/g), cycle stability (97%), and rate performance (84.1% in 10 C/0.1 C) than that of pristine graphite.