bluuebunny/crossref_metadata_2025_split huggingface dataset:
Galvanic Corrosion of AA5052 Aluminum-Magnesium Alloy and Carbon Steel in NaCl Solutions
Authors: Urase Gaku , Tada Eiji , Nishikata Atsushi 
Published: February 2020

Aluminum alloys (AAs) such as 5000 and 6000 series, which show relatively good corrosion resistance and plastic workability, have been utilized to automobile body parts for reducing the weight of the body and for the improvement of fuel consumption. However, since the body parts made of Al alloys should be joined with steel parts by welding or other methods and the joined parts can be exposed to atmospheric corrosion environments, there has been a concern about degradation of the parts due to galvanic corrosion between Al alloy and steel. In this study, galvanic corrosion behavior of AA5052 aluminum-magnesium alloy and SS400 carbon steel is investigated in NaCl solutions.
A galvanic couple used in this study consisted of AA5052 Al-Mg alloy (Mg: 2.65, Si: 0. 08, Fe: 0.27, Cu: 0.01, Cr: 0.17, Zn:0.01, Al: bal. (mass%)) and carbon steel (JIS SS400). Both materials were 15-mm-square plates of 3 mm in thickness. After lead wire was connected on the surface of the plates, they were embedded in an epoxy resin. At this time, both materials were separated with a 500-um gap. The surface of the galvanic couple was polished with SiC papers down to JIS 2000 grit and rinsed in EtOH. Galvanic corrosion experiments were done in aqueous NaCl solutions of various concentrations ranging from 5 mM to 500 mM. Galvanic current and corrosion potential of the couple were measured during the immersion in the solutions.
When a galvanic couple was immersed in a NaCl solution, galvanic current decreased gradually with immersion time and reached almost a constant value. On the other hand, corrosion potential for the galvanic couple showed complex behavior with immersion time. Just after immersion, the corrosion potential decreased in the less noble direction, which may be due to the initiation of corrosion of AA5052, and then after reaching the minimum value, the corrosion potential started to increase to a noble potential. Although the corrosion potential and the magnitude of the galvanic current were different depending on the concentration of the NaCl solutions, they did not change in a regular manner as a function of the NaCl concentrations. The changes in the corrosion potential and the galvanic current may be related to the transition of anodic dissolution behavior of AA5052 in the NaCl solutions of different concentrations.
Evaluation of Ant-Nest Corrosion Rate of Copper in Formic Acid Vapor
Authors: Kumakura Sayoko , Hayashi Michitaka , Tada Eiji , Nishikata Atsushi 
Published: February 2020

Copper is used for electric wires, pipes, heat exchanger, etc. because of good workability, electrical conductivity, thermal conductivity and corrosion resistance. However, copper suffers from a kind of pitting corrosion, so-called ant-nest corrosion, in the present of organic acids such as formic or acetic. The pit has a characteristic form, that is, there are many branches within the pit like ant-nest. The morphology is very complicated. The growth rate of the pit and the detailed mechanism are not yet clarified. In this study, pure copper foils of different thickness were exposed to formic acid vapor in order to evaluate the rate at which the ant-nest corrosion proceeds.
Pure copper foils (99.96 %) were used as a sample. The thickness was varied from 2 μm to 500 μm. The copper foils were cut into a small piece of 20 mm x 20 mm. The samples were degreased with acetone. Exposure test was done in a transparent capped glass container. The sample was fixed with adhesive agent on the inside wall of the cap of the container. Formic acid solution of 30 mL was set in the bottom of the container. In this way, only one surface (downside) of the copper foil was exposed to formic acid vapor. The concentrations of the formic acid were varied from 500 ppm to 10000 ppm.
In this study, progress rate of ant-nest corrosion was evaluated as follows. The copper foils of different thicknesses were set in the container, as mentioned above, where only one side surface of the sample was exposed to formic acid vapor. The time it took for a pit to first penetrate to the back side of the sample was measured by observing the back side (upside) with a microscope.
Fig.1 shows the result of the exposure test of copper foils to 10000 ppm formic acid vapor at 25 °C. The vertical axis indicates time to pit penetration to the backside t
pit and the horizontal axis shows the thickness of the copper foil. In other words, Fig.1 indicates the relationship between the maximum depth of pitting corrosion (horizontal axis) and the exposure time (vertical axis). It seems that pit growth in depth direction will occur linearly with time at initial stage, although the data over 100 h were scattered. The pit can progress to maximum 500 μm depth at 120 days in 10000 ppm formic acid vapor. Influences of temperature and formic acid concentration on the pit growth will be discussed.

Figure 1
Numerical Models of Cathodic Protection for Buried Steel Pipes Under Insulator Coating Layer
Authors: Odahara Masashi , Tsuchiya Hiroaki , Fujimoto Shinji 
Published: February 2020

Buried steel pipes are protected by insulator coatings such as polyethylene and rubber from corrosion under practical use. Furthermore, cathodic protection is often applied to prevent corrosion at locations where the insulator coatings are damaged and removed. However, when the coatings are peeled off, a large crevice is formed above the buried steel surfaces. This leads to the undesirable situation that the locations away from the open mouth of a crevice are not protected by the process as the cathodic current does not reach the locations. In the present work, in order to get insight on reactions and chemistries occurred in the large crevice generated above buried steel pipes with insulator coatings, numerical simulations on the corrosion behavior of buried steel pipes in two different types of crevice in ground water were performed.
Two-dimensional crevices were considered for the simulation; for one model, the open mouth was created on one side of crevice (defined as one open mouth model hereafter) while for the other, the open mouths were created on both sides of crevice (defined as two open mouths model). Boundary conditions for the simulations were provided at the open mouths and chemicals considered in the simulations were H+, OH-, Na+, Cl-, Fe2+ and Fe(OH)2. The simulations were carried out based on Tafel’s equation and Fick’s first law of diffusion assuming iron oxidation, oxygen reduction and hydrogen reduction are occurred at the interface between ground water and steel surface. The effects of the cathodic protection, the crevice thickness and the flow in crevice were evaluated.
In the one open mouth model, as the inflow of oxygen to the crevice is limited and as the result, dissolved oxygen in the crevice was rapidly consumed as cathodic reaction after the simulation commenced, the anodic current attributed to the iron oxidation was relatively small when cathodic protection was not applied. On the other hand, when cathodic protection was applied, the decrease in the anodic current was recognized near the open mouth, but no changes in the anodic current were confirmed at locations relatively away from the open mouth, indicating that cathodic current does not reach the locations. In the two open mouths model where flux of ground water is generated from one end to the other within the crevice, as the supply of oxygen was increased near the entry side by the flux of ground water, the anodic current increased near the entry side. The increase in the crevice width led to the further increase in the anodic current. Therefore, it was revealed that the formation of the crevice where the flux can be generated and/or the crevice with large width should be prevented.
Electrolytes without Ethylene Carbonate for High Voltage NMC/Graphite Li-Ion Cells
Authors: Dahn Jeff R , Xia Jian , Petibon Remi , Glazier Stephen , Nelson Kathlyne , Abarbanel Dan , Xiong Deijun , Ellis Leah , Louli Alex 
Published: February 2020

Ethylene carbonate is used in virtually every lithium-ion cell. In efforts to produce high voltage NMC/graphite cells, electrolytes without ethylene carbonate are being explored. The use of electrolytes based on fluoroethylene carbonate (FEC), difluoroethylene carbonate (di-FEC), bis(2,2,2-trifluoroethyl) carbonate (TFEC) and other solvents are explored in this presentation. Studies using ultra high precision coulometry, impedance spectroscopy, isothermal battery microcalorimetry, in-situ gas evolution, storage testing, XPS and long-term charge-discharge testing show the benefits and drawbacks of such electrolytes. Although progress is being made, there remains substantial work to do to produce high energy denisty NMC/graphite cells which can operate for years to 4.5 V. This work was done by Jian Xia, Remi Petibon, Steven Glazier, Kathlyne Nelson, Dan Abarbanel, Deijun Xiong, Leah Ellis and Alex Louli. The authors thank Xiaodong Cao of HSC Corporation for kindly providing many of the solvents used in the work.
Developments of Lithium Solid Electrolytes and their Application to All Solid-State Batteries
Authors: Kanno Ryoji 
Published: February 2020

Lithium solid electrolytes promise the potential to replace organic liquid electrolytes and thereby improve safety of the next-generation batteries. Among the electrolytes proposed, the sulphide system is a candidate for practical batteries because of their high ionic conductivity; the Li10GeP2S12 (LGPS) phase exhibits high ionic conductivity of over 10-2 S cm-1 at room temperature and is promising for applications requiring batteries with high powers and energy densities. The present study focuses on several topics of the all solid-state system using the inorganic electrolytes. (i) Material varieties of the LGPS system may provide suitable combinations of the electrodes and the electrolyte. To improve the materials variety, the substitution systems with the LGPS type structure were examined, and their phase diagram, structure and ionic conduction were studied. (ii) The combination with high-voltage electrode or high-capacity electrode may provide high capacity systems. The all solid-state batteries using various electrode materials were examined. (iii) The reaction at the electrolyte/electrode interface is the important issue to improve the stability and rate capabilities. High resistance at the interface of the solid-state system might prevent their usage for high current battery systems. Reactions at the interface were also examined. Based on these experimental results, the battery characteristics of the all solid-state system using LGPS electrolytes will be discussed.
Battery Safety Performance and Modeling
Authors: Miller Ted J. 
Published: February 2020

Advanced lithium ion batteries are a critical enabler to vehicle electrification. However, there are technology challenges which must be understood in order to ensure battery safety. Battery behavior in the event crush due to a crash, and other safety issues such as overcharge, short circuit, and overheating, must be understood and addressed in the vehicle system design. This talk will focus on the development of a battery safety performance simulation tool which can provide insight into battery safety behavior under a range of mechanical, electrical, and thermal extremes. When complete, the modeling tool will allow vehicle and battery system designers to simulate a wide spectrum of abuse conditions. Dedicated work in this important area has been undertaken by the Ford Energy Storage and Materials Research Team for the past several years, including a multi-year contract with the DOT/NHTSA on the Safety Performance of Rechargeable Energy Storage Systems. Ford’s present effort on the development and validation of a battery safety performance simulation tool is also supported the U.S. Department of Energy.
What is the Best Anode Material to Achieve High Energy Li-ion Batteries in Next 5 Years?
Authors: Cho Jaephil 
Published: February 2020

In spite of some technical advances in mitigatingthe volume-change problem toward the practical application of Si anodes, several challenges are still remained and should be resolved. First, the development of noble surface-coating methods and stable electrolytes for reducing the side reactions should be considered to stabilize the SEI of the Si anode. Although reducing methods of the HF derived from fluoroethylene carbonate (FEC), which is widely used in Si anodes to stabilize the SEI layer, is required because substantial capacity fading occurs as the HF attacks both the cathodes and Si. Second, in order to apply the Si anode to commercial LIBs and to achieve a high energy density, the change in the electrode thickness after tens of cycles should be examined in calendared Si anodes having an electrode density greater than 1.6 g cc-1, as an industrial standard. Based upon these requirements, I presents the best anode material, along with the real full cell test results.
Design and Investigation on Soft-Packed Sodium-Ion Batteries Based on Layered Sodium Transition Metal Oxide Cathodes
Authors: Wang Hong , Liao Xiao-Zhen , He Yu-Shi , Ma Zi-Feng 
Published: February 2020

Sodium ion battery (SIB) technology is considered as an attractive alternative to lithium ion batteries for the large scale energy storage systems due to vast availability of sodium resource. Up to now, much research effort has been devoted to the exploration of advanced electrode materials for SIBs. In order to promote the industrialization of sodium ion batteries, we scale up the synthesis of layered oxides NaxMO2 (M: Fe, Mn, Ni, Cu, Ti) using facile hydroxide co-precipitation combined with following calcination method. The obtained cathode materials showed good rate performance and excellent cycling stability even at low temperature. The Nax(Fe0.5Mn0.5)O2 cathode showed excellent reversibility between 2.0 V and 4.0 V with reversible capacity of 100 mAh g-1 (0.1 C). After Ni doping, the Nax(Fe0.5Ni0.3Mn0.2)O2
cathode showed good rate performance and excellent cycling stability with an initial capacity of 130 mAh g-1 at 1C. When hard carbon was used as anode, we designed soft-packed batteries with capacities ranging from 0.5Ah to 5Ah. Electrochemical behaviors of the batteries at different temperatures were studied and thermal stability of these batteries was also evaluated.
A 0.1KWh sodium ion battery pack was fabricated and evaluated as shown in Fig.1. The sodium ion packs can be assembled and used in portable energy storage device, household electrical energy storage, smart grid and low-speed electric vehicle, etc.
The authors are grateful for the financial support of this work by the Natural Science Foundation of China (21573147, 21506123, 21336003) and the 973 Program of China (2014CB239700).

Figure 1
Polypyrrole Films Derived from Vapor Phase Polymerization As Free-Standing Anodes for Li-Ion and Na-Ion Batteries
Authors: Yuan Tao , Zheng Shiyou 
Published: February 2020

Recently, lightweight, bendable and wearable electronic devices have been prevailing in the markets, there is a strong demand for high performance flexible electrode-active materials without binder and conductive agent that possess a high flexibility and energy capacity [1-3]. Li-ion batteries have received great attention as power sources for portable electronic devices, hybrid electric vehicles and energy storage system. However, considering the limited and uneven distribution of lithium minerals, room temperature Na-ion batteries have received growing attention because of their low cost and abundant supply. Na-ion batteries and Li-ion batteries share the same architecture of battery design. One of the major challenges for Na-ion batteries is to discover suitable electrode materials with high and stable sodium storage capabilities.
We propose here a polypyrrole (PPy) thin film synthesized by an easy, inexpensive and scalable vapor phase polymerization (VPP) technique (Figure 1) [3]. As shown in Figure 1, the obtained PPy film shows smooth surface and continuously cross-linked structure. From the XRD and HR-TEM results (Figure 1), the obtained PPy film possesses well-ordered crystallized structure, which is helpful for Li+ and Na+charges transfer and storage. The as-derived free-standing PPy film anodes exhibit high rate performance and stable cycling life for both Li-ion batteries and Na-ion batteries.
Detailed electrochemical properties and the structural transformation during charge-discharge processes of PPy film as anodes for Li-ion batteries and Na-ion batteries will be presented at the meeting.
Acknowledgements:
The authors gratefully acknowledge the support of the National Science Foundation of China (21403139, 51472161, 51472160), the Shanghai Pujiang Program (No. 14PJ1407100), the Key Program for the Fundamental Research of the Science and Technology Commission of Shanghai Municipality (15JC1490800, 12JC1406900) and the International Cooperation Program of the Science and Technology Commission of Shanghai Municipality (14520721700). We acknowledge the support of the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning (TP2014048) and the Hujiang Foundation of China (B14006).
References:
[1] S. Zheng, Y. Chen, Y. Xu, F. Yi, Y. Zhu, Y. Liu, J. Yang, C. Wang, ACS nano, 10995-11003, 7 (2013).
[2] T. Yuan, B. Zhao, R. Cai, Y. Zhou, Z. Shao, J. Mater. Chem.,
15041-15048, 21 (2011).
[3] T. Yuan, Y-S. He, W. Zhang, Z-F. Ma, Chem. Commun., 112-115, 52 (2016).

Figure 1
Thin Film Cathodes for Lithium and Beyond Lithium-Ion Batteries
Authors: Feng Zhenxing , Burrell Anthony K. , Fenter Paul 
Published: February 2020

The development of advanced batteries that have a higher energy density for current lithium-ion and beyond lithium-ion battery relies not only on the identification of new chemistries (e.g., a compatible combination of cathode, anode and non-aqueous electrolyte), but also mechanistic understanding of cathode performance during charge-discharge processes. For these reasons we focus on model thin film systems, which provide controllable geometry, orientation and surface roughness. Using pulsed laser deposition, we have grown lithium-based (e.g., LiMn2O4) and magnesium based (MgMn2O4) oxide thin films. Using these model systems, we have explored the electrochemical performance of these materials as new battery cathodes, as well as the intercalation mechanism of cations, namely Mg2+ and Li+, at the electrode/electrolyte interfaces. For example, the cubic phase of MgMn2O4 (MMOC) can only be found in powder form at high temperature (> 950 °C) or high pressure (> 15.6 GPa), but is stabilized as thin films, which exhibited reversible Mg2+ insertion and extraction in non-aqueous electrolyte such as Mg(TFSI)2 in diglyme with associated changes in bulk film structure and Mn-oxidation states. Using in situ X-ray reflectivity we have observed the film structural changes during charge-discharge processes. Our thin film model system studies provide a platform for material design and mechanistic understanding for lithium and beyond lithium-ion batteries.
This work was supported by the Joint Center for Energy Storage Research (JCESR) through the Office of Basic Energy Sciences (BES), U.S. Department of Energy (DOE).
Advanced Electrolyte for Rechargeable Magnesium Batteries
Authors: Ha Jung-Hoon , Cho Byung-Won , Nazar Linda F , OH SI Hyoung 
Published: February 2020

Recently, rechargeable magnesium batteries gains more and more attention as a commercially-viable future energy storage system for mid-/large-scale applications such as ESS and electric vehicles (EV).[1-4] Magnesium is attractive as an anode material, since it is not only naturally abundant, but delivers a high gravimetric and volumetric capacity of 2,205 mAh/g and 3,833 mAh/cm3 at relatively low reduction potential of -2.372 V vs. standard hydrogen electrode. Therefore, batteries based on magnesium metal negative electrode can be potentially manufactured at very low cost and possess a market competitiveness in their energy density. However, the most intriguing problems of these systems are slow development of electrolyte systems having a reversible Mg plating/stripping character on the anode without a dendrite formation and at the same time exhibiting a wide electrochemical window, which would hire a cathode material having a high electrode potential for the high energy density of the system. It is well-known that the conventional Grignard solution (RMgX, R = alkyl or aryl, X = Cl, Br) which has a good reversibility on Mg plating/stripping reaction, functions as strong nucleophile and its anodic stability is poor so that it cannot be applied to common cathode materials. In this work, we will present a new electrolyte system which can be prepared by a simple process and can be directly applied to magnesium electrode with a high coulombic efficiency more than 99.9 % and stability up to 4.0 V vs. magnesium electrode. We will characterize this electrolyte system through many analysis tools including NMR, single-crystal XRD and other spectroscopic methods. We will also show that full cells employing Mo6S8 Chevrel phase cathode and this new electrolyte can be run for hundreds of cycles without a noticeable capacity fading.

References

[1] D. Aurbach et al., Nature, 407(2000) 724
[2] D. Aurbach et al., Energy Environ. Sci., 6 (2013) 2265.
[3] R. Mohtadi et al., Beilstein J. Nanotechnol., 5(2014) 1291.
[4] J. Muldoon et al., Energy Environ. Sci.,
5 (2012) 5941.
To Break or Not to Break: Solution and Surface Mechanisms of DMSO Decomposition in Aprotic Li-O2 Battery Electrolytes
Authors: Scheers Johan , Sodeyama Keitaro , Tateyama Yoshitaka 
Published: February 2020

The aprotic Li-O2 battery offers an appealing opportunity to make use of atmospheric oxygen (together with metallic lithium) to achieve batteries with truly remarkable energy densities. However, oxygen is reduced to superoxides and peroxides, which react irreversibly with most materials; non-aqueous electrolytes, binders, and cathodes – hindering stable and rechargeable battery operation. Therefore, preventing parasitic reactions, in particular developing stable electrolytes, is critical for progress.
Dimethyl sulfoxide (DMSO) is a promising solvent for Li-O2 battery electrolytes. It has been scrutinized both experimentally and computationally, but there are conflicting opinions on the stability of DMSO. Experimental work by Kwabi et al. [1] and computational results by Laino et al. [2] suggest that DMSO is readily oxidized to dimethyl sulfone (DMSO2) at Li2O2 surfaces, also forming LiOH. These results have, however, been challenged by Schroeder et al. [3], claiming that DMSO is sufficiently stable in the presence of Li2O2 – as long as there are no other sources of acidic protons present that can initiate decomposition by forming more reactive hydroperoxy species.

More fundamental research on the reaction mechanisms of DMSO with reduced oxygen species is needed to resolve this contradiction. In this work we have used DFT-MD to model DMSO decomposition by LiO2 in solution and by Li2O2 surfaces. We present reaction energies and barriers to reactions for alternative decomposition mechanisms; proton abstraction (DMSO-H), methyl abstraction (DMSO-CH3), and addition reactions (DMSO2) with the aim of better understanding the relative importance of surface and solution reactions, the reacting oxygen species, and the mechanisms of reaction.

References

[1] D.G. Kwabi et al., J. Phys. Chem. Lett.
5 (2014) 2850.
[2] T. Laino et al., New J. Phys. 15 (2013) 095009.
[3] M.A. Schroeder et al., ACS Appl. Mater. Interfaces. 7 (2015) 11402.

Figure
Free energy of methyl abstraction reaction between DMSO and LiO2 in solution phase (left). Highlight of transition state geometry (right). DFT-MD, PBE functional, T=353K.

Figure 1