Impact of Graphite Materials on the Lifetime of NMC811/Graphite Pouch Cells: Part II. Long-Term Cycling, Stack Pressure Growth, Isothermal Microcalorimetry, and Lifetime Projection

Abstract Part II of this 2-part series examines the impact of various graphite materials on NMC811 pouch cell performance using Ultra-High Precision Coulometry (UHPC), isothermal microcalorimetry, and in-situ stack growth. A simple lifetime projection of the best NMC811/graphite cells as a function of operating temperature is made. We show that graphite choice greatly impacts fractional fade, while fractional charge endpoint capacity slippage was largely unchanged. We show that an increase in 1st cycle efficiency due to limited redox-active sites, which is favourable for minimizing Li inventory loss, is concomitant with an increase in negative electrode charge transfer resistance. Further, we demonstrate that cells with competitive artificial graphites (AG) have a lower parasitic heat flow (~0.060 mW/Ahr at 40oC) compared to cells with natural graphites (NG), and that the cells with the AG materials had minimal stack thickness change with cycling. Finally, we model SEI growth for NMC811 cells limited to 4.06 V with the square-root time model, and project that the best NMC811/graphite cells can have a century of lifetime at 15 oC when Li plating during charge is avoided. Such cells are an excellent candidate for grid storage applications where energy density is less important compared to long lifetime.

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Electrochemical Decomposition of Poly(Vinylidene Fluoride) Binder for a Graphite Negative Electrode in Lithium-Ion Batteries

Materials Science Forum ◽

10.4028/www.scientific.net/msf.893.127 ◽

2017 ◽

Vol 893 ◽

pp. 127-131 ◽

Cited By ~ 1

Author(s):

Min Ji Kim ◽

Chang Hee Lee ◽

Mun Hui Jo ◽

Soon Ki Jeong

Keyword(s):

Lithium Ion Batteries ◽

Vinylidene Fluoride ◽

Electrochemical Impedance ◽

Negative Electrode ◽

Reduction Process ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Electrode Resistance ◽

Poly Vinylidene Fluoride

To clarify the electrochemical decomposition of poly (vinylidene fluoride) (PVdF) used as a binder for lithium-ion batteries while simultaneously verifying the correlation between electrode resistance and the PVdF content in graphite negative electrodes, in this study, we applied lithium bis (trifluoromethanesulfonyl) imide, which suppresses graphite exfoliation, as a salt. As a result, the electrochemical decomposition of PVdF was observed at a higher potential than that at which the electrolyte was decomposed during the reduction process. Additionally, this study demonstrated (through electrochemical impedance spectroscopy analysis) that electrode resistances such as solid electrolyte interface and charge transfer resistance proportionally increased with the PVdF content.

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Electrochemical Properties of NbO as a Negative Electrode Material for Lithium Secondary Batteries

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.835.126 ◽

2016 ◽

Vol 835 ◽

pp. 126-130 ◽

Cited By ~ 1

Author(s):

Kyoung Soo Park ◽

Soon Ki Jeong ◽

Yang Soo Kim

Keyword(s):

Electrochemical Properties ◽

Ball Milling ◽

Electrode Material ◽

Negative Electrode ◽

Lithium Ion ◽

Reversible Capacity ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Lithium Secondary Batteries ◽

Negative Electrode Material

The electrochemical properties of niobium monoxide, NbO, were investigated as a negative electrode material for lithium-ion batteries. Lithium ions were inserted into and extracted from NbO material at potentials < 1.0 V versus Li/Li+, involving formation of a solid electrolyte interface (SEI) on the NbO surface in the first cycle. Its reversible capacity is ~67 mAh g–1 with the capacity retention of ~109% after 50 cycles. The magnitude of charge transfer resistance was greatly decreased by ball-milling the pristine NbO, whereas the ball-milling had no effect on the SEI resistance.

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THE INFLUENCE OF GRAIN SIZE OF PURE IRON METAL ON CORROSION INHIBITION IN PRESENCE OF SODIUM NITRITE

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512002760 ◽

2012 ◽

Vol 05 ◽

pp. 793-800 ◽

Cited By ~ 2

Author(s):

VAHID AFSHARI ◽

CHANGIZ DEHGHANIAN

Keyword(s):

Grain Size ◽

Aqueous Solutions ◽

Corrosion Inhibition ◽

Sodium Nitrite ◽

Active Sites ◽

Electrochemical Impedance ◽

Standard Free Energy ◽

Charge Transfer Resistance ◽

Free Energy Of Adsorption ◽

Transfer Resistance

The effects of grain size reduction on the corrosion inhibition of sodium nitrite were investigated using polarization curves and electrochemical impedance spectroscopy (EIS). Nanocrystalline iron (~ 45 nm) was produced by pulse electrodeposition using citric acid bath. The grain size of a nanocrystalline surface was analyzed by X-ray diffractometry (XRD) and field emission scanning electron microscopy (FESEM). The most intensive first-order peak (211) of the XRD patterns was taken for detailed analysis using a Gaussian fitting curve. The tests were carried out in 25 mg / l NaCl + 57 mg / l Na 2 SO 4 with different concentration of sodium nitrite aqueous solutions. The results revealed that due to the adsorption process which leads to the formation of a protective layer with a greater charge transfer resistance the inhibition effect and corrosion protection of sodium nitrite inhibitor in near-neutral aqueous solutions increased as the grain size decreased from microcrystalline to nanocrystalline. The standard free energy of adsorption ( ΔGads ) revealed a strong interaction between inhibitor and nanocrystalline surface. This was attributed to the increased number of the active sites caused by nanocrystalline surface.

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Asymmetric supercapacitor of functionalised electrospun carbon fibers/poly(3,4-ethylenedioxythiophene)/manganese oxide//activated carbon with superior electrochemical performance

Scientific Reports ◽

10.1038/s41598-019-53421-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 5

Author(s):

Muhammad Amirul Aizat Mohd Abdah ◽

Nur Hawa Nabilah Azman ◽

Shalini Kulandaivalu ◽

Yusran Sulaiman

Keyword(s):

Activated Carbon ◽

Manganese Oxide ◽

High Performance ◽

Storage System ◽

Negative Electrode ◽

Energy Storage System ◽

Charge Transfer Resistance ◽

Potential Candidate ◽

Transfer Resistance ◽

Operating Potential

AbstractAsymmetric supercapacitors (ASC) have shown a great potential candidate for high-performance supercapacitor due to their wide operating potential which can remarkably enhance the capacitive behaviour. In present work, a novel positive electrode derived from functionalised carbon nanofibers/poly(3,4-ethylenedioxythiophene)/manganese oxide (f-CNFs/PEDOT/MnO2) was prepared using a multi-step route and activated carbon (AC) was fabricated as a negative electrode for ASC. A uniform distribution of PEDOT and MnO2 on f-CNFs as well as porous granular of AC are well-observed in FESEM. The assembled f-CNFs/PEDOT/MnO2//AC with an operating potential of 1.6 V can achieve a maximum specific capacitance of 537 F/g at a scan rate of 5 mV/s and good cycling stability (81.06% after cycling 8000 times). Furthermore, the as-prepared ASC exhibited reasonably high specific energy of 49.4 Wh/kg and low charge transfer resistance (Rct) of 2.27 Ω, thus, confirming f-CNFs/PEDOT/MnO2//AC as a promising electrode material for the future energy storage system.

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Macromolecular Engineering of Poly(catechol) Cathodes towards High-Performance Aqueous Zinc-Polymer Batteries

Polymers ◽

10.3390/polym13111673 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1673

Author(s):

Nagaraj Patil ◽

Jesus Palma ◽

Rebeca Marcilla

Keyword(s):

High Performance ◽

Rate Capability ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Metal Anode ◽

Redox Active ◽

Diffusion Controlled ◽

Metal Organic ◽

Improved Performance ◽

Organic Batteries

Aqueous zinc-polymer batteries (AZPBs) comprising abundant Zn metal anode and redox-active polymer (RAP) cathodes can be a promising solution for accomplishing viable, safe and sustainable energy storage systems. Though a limited number of RAPs have been successfully applied as organic cathodes in AZPBs, their macromolecular engineering towards improving electrochemical performance is rarely considered. In this study, we systematically compare performance of AZPB comprising Zn metal anode and either poly(catechol) homopolymer (named P(4VC)) or poly(catechol) copolymer (named P(4VC86-stat-SS14)) as polymer cathodes. Sulfonate anionic pendants in copolymer not only rendered lower activation energy and higher rate constant, but also conferred lower charge-transfer resistance, as well as facilitated Zn2+ mobility and less diffusion-controlled current responses compared to its homopolymer analogue. Consequently, the Zn||P(4VC86-stat-SS14) full-cell exhibits enhanced gravimetric (180 versus 120 mAh g−1 at 30 mg cm−2) and areal capacity (5.4 versus 3.6 mAh cm−2 at 30 mg cm−2) values, as well as superior rate capability both at room temperature (149 versus 105 mAh g−1 at 150 C) and at −35 °C (101 versus 35 mAh g−1 at 30 C) compared to Zn||P(4VC)100. This overall improved performance for Zn||P(4VC86-stat-SS14) is highly encouraging from the perspective applying macromolecular engineering strategies and paves the way for the design of advanced high-performance metal-organic batteries.

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Microstructure, Mechanical Properties, and Corrosion Behavior of Ultra-Low Carbon Bainite Steel with Different Niobium Content

Materials ◽

10.3390/ma14020311 ◽

2021 ◽

Vol 14 (2) ◽

pp. 311

Author(s):

Yun Zong ◽

Chun-Ming Liu

Keyword(s):

Impact Toughness ◽

Electrochemical Impedance ◽

Charge Transfer Resistance ◽

Granular Bainite ◽

Low Carbon ◽

Transfer Resistance ◽

Niobium Content ◽

Maximum Charge ◽

Low Carbon Bainite ◽

The Impact

Four types of ultra-low carbon bainite (ULCB) steels were obtained using unified production methods to investigate solely the effect of niobium content on the performance of ULCB steels. Tensile testing, low-temperature impact toughness testing, corrosion weight-loss method, polarization curves, electrochemical impedance spectroscopy (EIS), and the corresponding organizational observations were realized. The results indicate that the microstructure of the four steels comprise granular bainite and quite a few martensite/austenite (M/A) elements. The niobium content affects bainite morphology and the size, quantity, and distribution of M/A elements. The elongation, yield strength, and tensile strength of the four types of ULCB steels are above 20%, 500 MPa, and 650 MPa, respectively. The impact toughness of the four types of ULCB steels at −40 °C is lower than 10 J. Steel with Nb content of 0.0692% has better comprehensive property, and maximum charge transfer resistance in 3.5 wt.% NaCl solution at the initial corrosion stage. The corrosion products on the surface of steel with higher niobium content are much smoother and denser than those steel with lower niobium content after 240 h of corrosion. The degree of corrosion decreases gradually with the increase of niobium content at the later stage of corrosion.

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Carbon Nanotube Paper as Anode for Flexible Lithium-Ion Battery

NANO ◽

10.1142/s1793292016501204 ◽

2016 ◽

Vol 11 (11) ◽

pp. 1650120 ◽

Cited By ~ 6

Author(s):

Xiaogang Sun ◽

Zhenhong Liu ◽

Neng Li ◽

Xiaoyong Wu ◽

Yanyan Nie ◽

...

Keyword(s):

Carbon Nanotube ◽

Electrochemical Performance ◽

Lithium Ion Battery ◽

Electrochemical Impedance ◽

Negative Electrode ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

Electrochemical Performances ◽

Multiwalled Carbon ◽

Transfer Resistance

In this investigation, multiwalled carbon nanotube (MWCNT) paper consists of MWCNTs and cellulose was fabricated by traditional paper-making method. It was applied directly as negative electrode in flexible lithium ion battery to replace ordinary electrode which is combined with anode material and current collector. The electrochemical performances of the as-produced MWCNT paper (AMP) and carbonized MWCNT paper (CMP) were evaluated in this study. The morphology and structure of the MWCNT papers were observed by scanning electron microscopy (SEM). The electrochemical performance of the battery was operated by cell test and electrochemical impedance spectroscopy (EIS) measurement. The charging and discharging results indicated that the CMP behaves with higher capacity than AMP. And the EIS analysis showed that a lower charge transfer resistance can be obtained in the CMP. The excellent electrochemical performance verifies the feasibility of MWCNT papers as a promising candidate for the anode in flexible lithium ion battery.

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Electrochemical behavior for corrosion protection of mild steel (MS) in 1M HCl medium by using lidocaine drug as an inhibitor

Zastita materijala ◽

10.5937/zasmat2004286a ◽

2020 ◽

Vol 61 (4) ◽

pp. 286-305

Author(s):

Ali Adel ◽

El-Aziz Abd ◽

Tilp Amal

Keyword(s):

Weight Loss ◽

Mild Steel ◽

Electrochemical Impedance ◽

Charge Transfer Resistance ◽

Open Circuit ◽

Effect Of Temperature ◽

Adsorption Parameters ◽

Transfer Resistance ◽

Surface Examination ◽

The Impact

The impact of Lidocaine as a save corrosion inhibitor for mild steel (MS) in 1M HCl by using weight loss (WL), Hydrogen evaluation (HE), open circuit potential (EO C P), potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS) and Electrochemical frequency modulation (EFM) techniques has been investigated. Weight loss studied at various temperatures between (25-45oC) but Hydrogen evaluation and electrochemical studies at room temperature. The effect of temperature on the inhibition of corrosion has been studied and the thermodynamic activation and adsorption parameters were calculated. The morphology of MS was examined by scanning electron microscope with energy dispersive X-ray spectroscopy (SEM-EDX) technology and atomic force microscopy (AFM). EIS data indicate that in the presence of drug the double layer capacitance was decreased and the charge transfer resistance increased. The adsorption of the Lidocaine on MS surface was found to obey Langmuir adsorption isotherm and elucidate the mechanism of corrosion inhibition. The Lidocaine drug acts as mixed type inhibitor. All surface examination confirms the formation thin film covered the surface of the metal and prevent the surface of the metal from corrosion.

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Correlating the Layer Properties of Ni-alumina Composite Coatings and the Mechanism of Codeposition

International Journal of Chemistry ◽

10.5539/ijc.v8n2p110 ◽

2016 ◽

Vol 8 (2) ◽

pp. 110 ◽

Cited By ~ 1

Author(s):

Amir Sadeghi ◽

Maximilian Sieber ◽

Hosein Hasannejad ◽

Ingolf Scharf ◽

Thomas Lampke

Keyword(s):

Double Layer ◽

Electrochemical Impedance ◽

Composite Coatings ◽

Charge Transfer Resistance ◽

Nano Particles ◽

Submicron Particles ◽

Transfer Resistance ◽

Alumina Particles ◽

Alumina Composite ◽

The Impact

Ni-Al2O3 composite coatings electrodeposited from Watt’s electrolyte include Al2O3 nano-and submicron particles. The effect of particle size and concentration of the particles in the electrolyte were investigated on the morphology and incorporation value of particles into the deposits. The influence of alumina particles on the electrodeposition behavior of Ni was also studied by means of electrochemical impedance spectroscopy. The results achieved from the impedance measurements and the correlation with the layer characterization could help to better understand the codeposition mechanism derived from the impact of different particle characteristics including size and concentration on the nature of the double-layer. The increase in the concentration of particles from 1 to 20 g/l resulted in an increase of the double-layer capacity and decrease of the charge transfer resistance, while the addition of submicron particles had a higher influence on the characteristics of the double-layer compared to the nano particles. Although the alumina particles with submicron size could stimulate the incorporation of particles faster than those with nano size, the strengthening performance of the layers not only depended on the incorporation value of the particles, but also on the microstructure of the deposits.

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Improvement of Ti/RuO2–IrO2 Anode Lifetime and Electrocatalytical Properties by Using an Eco-Friendly Thermal Decomposition Method Using Polyvinyl Alcohol as Solvent

10.26434/chemrxiv.7991129 ◽

2019 ◽

Author(s):

Charlys Bezerra ◽

Géssica Santos ◽

Marilia Pupo ◽

Maria Gomes ◽

Ronaldo Silva ◽

...

Keyword(s):

Thermal Decomposition ◽

Polyvinyl Alcohol ◽

High Efficiency ◽

Electrochemical Impedance ◽

Pechini Method ◽

Low Cost ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Calcination Temperatures ◽

Service Lifetime

Electrochemical oxidation processes are promising solutions for wastewater treatment due to their high efficiency, easy control and versatility. Mixed metal oxides (MMO) anodes are particularly attractive due to their low cost and specific catalytic properties. Here, we propose an innovative thermal decomposition methodology using <a>polyvinyl alcohol (PVA)</a> as a solvent to prepare Ti/RuO2–IrO2 anodes. Comparative anodes were prepared by conventional method employing a polymeric precursor solvent (Pechini method). The calcination temperatures studied were 300, 400 and 500 °C. The physical characterisation of all materials was performed by X-ray diffraction and scanning electron microscopy coupled with energy dispersive spectroscopy, while electrochemical characterisation was done by cyclic voltammetry, accelerated service lifetime and electrochemical impedance spectroscopy. Both RuO2 and IrO2 have rutile-type structures for all anodes. Rougher and more compact surfaces are formed for the anodes prepared using PVA. Amongst temperatures studied, 300 °C using PVA as solvent is the most suitable one to produce anodes with expressive increase in voltammetric charge (250%) and accelerated service lifetime (4.3 times longer) besides reducing charge-transfer resistance (8 times lower). Moreover, the electrocatalytic activity of the anodes synthesised with PVA toward the Reactive Blue 21 dye removal in chloride medium (100 % in 30 min) is higher than that prepared by Pechini method (60 min). Additionally, the removal total organic carbon point out improved mineralisation potential of PVA anodes. Finally, this study reports a novel methodology using PVA as solvent to synthesise Ti/RuO2–IrO2 anodes with improved properties that can be further extended to synthesise other MMO compositions.

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