Linking capacity loss and retention of nickel hexacyanoferrate to a two-site intercalation mechanism for aqueous Mg2+ and Ca2+ ions

2019 ◽  
Vol 21 (36) ◽  
pp. 20177-20188 ◽  
Author(s):  
Aniruddh Shrivastava ◽  
Sizhe Liu ◽  
Kyle C. Smith
Keyword(s):  
Host Lattice ◽  
Partial Substitution ◽  
Aqueous Electrolytes ◽  
Capacity Fade ◽  
Nickel Hexacyanoferrate ◽  
Galvanostatic Cycling ◽  
Capacity Loss

Partial substitution of Ni2+ in the host lattice of nickel hexacyanoferrate by Mg2+ or Ca2+ from aqueous electrolytes leads to rapid capacity fade during galvanostatic cycling, while capacity is retained by intercalation into interstitial sites.

Effect of the alkali insertion ion on the electrochemical properties of nickel hexacyanoferrate electrodes

2014 ◽  
Vol 176 ◽  
pp. 69-81 ◽  
Author(s):  
Hyun-Wook Lee ◽  
Mauro Pasta ◽  
Richard Y. Wang ◽  
Riccardo Ruffo ◽  
Yi Cui
Keyword(s):  
Electrochemical Properties ◽  
Low Cost ◽  
High Energy ◽  
Aqueous Electrolytes ◽  
Channel Diameter ◽  
Organic Electrolytes ◽  
Nickel Hexacyanoferrate ◽  
Alkali Ions ◽  
Large Channel ◽  
Power Capability

Nickel hexacyanoferrate (NiHCFe) is an attractive cathode material in both aqueous and organic electrolytes due to a low-cost synthesis using earth-abundant precursors and also due to its open framework, Prussian blue-like crystal structure that enables ultra-long cycle life, high energy efficiency, and high power capability. Herein, we explored the effect of different alkali ions on the insertion electrochemistry of NiHCFe in aqueous and propylene carbonate-based electrolytes. The large channel diameter of the structure offers fast solid-state diffusion of Li+, Na+, and K+ ions in aqueous electrolytes. However, all alkali ions in organic electrolytes and Rb+ and Cs+ in aqueous electrolytes show a quasi-reversible electrochemical behavior that results in poor galvanostatic cycling performance. Kinetic regimes in aqueous electrolyte were also determined, highlighting the effect of the size of the alkali ion on the electrochemical properties.

scholarly journals Novel Approaches for Solving the Capacity Fade Problem during Operation of a Vanadium Redox Flow Battery

Batteries ◽  
2018 ◽  
Vol 4 (4) ◽  
pp. 48 ◽  
Author(s):  
Arjun Bhattarai ◽  
Purna Ghimire ◽  
Adam Whitehead ◽  
Rüdiger Schweiss ◽  
Günther Scherer ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Large Scale ◽  
Vanadium Redox Flow Battery ◽  
Electrolyte Imbalance ◽  
Capacity Fade ◽  
Redox Flow Battery ◽  
Flow Battery ◽  
Safety Issues ◽  
Capacity Loss ◽  
Vanadium Redox

The vanadium redox flow battery (VRFB) is one of the most mature and commercially available electrochemical technologies for large-scale energy storage applications. The VRFB has unique advantages, such as separation of power and energy capacity, long lifetime (>20 years), stable performance under deep discharge cycling, few safety issues and easy recyclability. Despite these benefits, practical VRFB operation suffers from electrolyte imbalance, which is primarily due to the transfer of water and vanadium ions through the ion-exchange membranes. This can cause a cumulative capacity loss if the electrolytes are not rebalanced. In commercial systems, periodic complete or partial remixing of electrolyte is performed using a by-pass line. However, frequent mixing impacts the usable energy and requires extra hardware. To address this problem, research has focused on developing new membranes with higher selectivity and minimal crossover. In contrast, this study presents two alternative concepts to minimize capacity fade that would be of great practical benefit and are easy to implement: (1) introducing a hydraulic shunt between the electrolyte tanks and (2) having stacks containing both anion and cation exchange membranes. It will be shown that the hydraulic shunt is effective in passively resolving the continuous capacity loss without detrimentally influencing the energy efficiency. Similarly, the combination of anion and cation exchange membranes reduced the net electrolyte flux, reducing capacity loss. Both approaches work efficiently and passively to reduce capacity fade during operation of a flow battery system.

scholarly journals Capacity Fade in Lithium-Ion Batteries and Cyclic Aging over Various State-of-Charge Ranges

2019 ◽  
Vol 11 (23) ◽  
pp. 6697 ◽  
Author(s):  
Sophia Gantenbein ◽  
Michael Schönleber ◽  
Michael Weiss ◽  
Ellen Ivers-Tiffée
Keyword(s):  
Particle Surface ◽  
High Capacity ◽  
Lithium Ion ◽  
Open Circuit ◽  
Operating Conditions ◽  
State Of Charge ◽  
Capacity Fade ◽  
Active Electrode ◽  
Capacity Loss ◽  
Aging Mechanisms

In order to develop long-lifespan batteries, it is of utmost importance to identify the relevant aging mechanisms and their relation to operating conditions. The capacity loss in a lithium-ion battery originates from (i) a loss of active electrode material and (ii) a loss of active lithium. The focus of this work is the capacity loss caused by lithium loss, which is irreversibly bound to the solid electrolyte interface (SEI) on the graphite surface. During operation, the particle surface suffers from dilation, which causes the SEI to break and then be rebuilt, continuously. The surface dilation is expected to correspond with the well-known graphite staging mechanism. Therefore, a high-power 2.6 Ah graphite/LiNiCoAlO2 cell (Sony US18650VTC5) is cycled at different, well-defined state-of-charge (SOC) ranges, covering the different graphite stages. An open circuit voltage model is applied to quantify the loss mechanisms (i) and (ii). The results show that the lithium loss is the dominant cause of capacity fade under the applied conditions. They experimentally prove the important influence of the graphite stages on the lifetime of a battery. Cycling the cell at SOCs slightly above graphite Stage II results in a high active lithium loss and hence in a high capacity fade.

Electrochemical Comparison of Chemically or Physically Modified Natural Graphite Anode for Lithium-Ion Batteries

2007 ◽  
Vol 124-126 ◽  
pp. 995-998
Author(s):  
Joong Pyo Shim ◽  
Hong Ki Lee ◽  
Byung Ho Song
Keyword(s):  
Heat Treatment ◽  
Carbon Black ◽  
Lithium Ion ◽  
Graphite Powder ◽  
Capacity Fade ◽  
Irreversible Capacity ◽  
Natural Graphite ◽  
Capacity Loss ◽  
Graphite Anodes ◽  
Powder Addition

Natural graphite anodes were treated by different methods to improve their cyclability. We tried following methods; heat-treatment at 550oC for graphite powder, addition of carbon black for electrode and VC (vinylene carbonate) in electrolyte. All methods decreased capacity fade rate during constant cycling. The addition of carbon black decreased capacity fade significantly but increased irreversible capacity much at first cycle. Heat-treatment and VC were also effective for cycling and irreversible capacity loss.

Electrochemical Behavior of LiCo(1-x)MnxO2 Crystalline Powders

2014 ◽  
Vol 895 ◽  
pp. 334-337
Author(s):  
Azira Azahidi ◽  
Norlida Kamarulzaman ◽  
Kelimah Elong ◽  
Nurhanna Badar ◽  
Nurul Atikah Mohd Mokhtar
Keyword(s):  
Partial Substitution ◽  
Li Ion Batteries ◽  
X Ray Diffraction ◽  
Capacity Retention ◽  
X Ray ◽  
Capacity Loss ◽  
Transition Metal Element ◽  
Metal Element ◽  
Li Ion ◽  
Mn Doped

LiCoO2 is a well-known cathode material used in commercial Li-ion batteries but it has its own limitations in terms of cost and toxicity. Improvement of the material by partial substitution of Co with other transition metals is one of the alternative and effective ways to overcome the limitations and improve the electrochemical performance of cathode materials. The transition metal element used for the substitution has to be cheaper and non-toxic thus Mn is chosen here. LiCo(1-x)MnxO2 (x= 0.1, 0.2, 0.3) we synthesized by a novel route using a self-propagating combustion (SPC) method. The samples are analyzed using X-Ray Diffraction (XRD) for phase purity and Field Emission Scanning Electron Microscopy (FESEM) for morphology and particle size studies. The materials obtained are phase pure. In terms of electrochemical activity, though it does not show better first cycle discharge capacity, the Mn doped materials have improved capacity retention. Results showed that LiCo0.9Mn0.1O2 and LiCo0.8Mn0.2O2 exhibited less than 8 % capacity loss in the 20th cycle compared to 12 % for LiCoO2.

scholarly journals A Comparison of Separators vs. Membranes in Nonaqueous Redox Flow Battery Electrolytes Containing Small Molecule Active Materials

2021 ◽  
Author(s):  
Zhiming Liang ◽  
N. Harsha Attanayake ◽  
Katharine Greco ◽  
Bertrand Neyhouse ◽  
John L. Barton ◽  
...  
Keyword(s):  
Coulombic Efficiency ◽  
Capacity Fade ◽  
Redox Flow Battery ◽  
Active Materials ◽  
Flow Cells ◽  
Organic Species ◽  
Capacity Loss ◽  
Stable Performance ◽  
Redox Flow Cells ◽  
Selective Membranes

<p>The lack of suitable membranes for nonaqueous electrolytes limits cell capacity and cycle lifetime in organic redox flow cells. Using soluble, stable materials, we sought to compare the best performance that could be achieved with commercially available microporous separators and ion-selective membranes. We use organic species with proven stability to avoid deconvoluting capacity fade due to crossover and/or cell imbalance from materials degradation. We found a trade-off between lifetime and coulombic efficiency: non-selective separators achieve more stable performance but suffer from low coulombic efficiencies, while ion-selective membranes achieve high coulombic efficiencies but experience capacity loss over time. When electrolytes are pre-mixed prior to cycling, coulombic efficiency remains high, but capacity is lost due to cell imbalance, which can be recovered by electrolyte rebalancing. The results of this study highlight the potential for gains in nonaqueous cell performance that may be enabled by suitable membranes.</p>

scholarly journals A Comparison of Separators vs. Membranes in Nonaqueous Redox Flow Battery Electrolytes Containing Small Molecule Active Materials

2021 ◽  
Author(s):  
Zhiming Liang ◽  
N. Harsha Attanayake ◽  
Katharine Greco ◽  
Bertrand Neyhouse ◽  
John L. Barton ◽  
...  
Keyword(s):  
Coulombic Efficiency ◽  
Capacity Fade ◽  
Redox Flow Battery ◽  
Active Materials ◽  
Flow Cells ◽  
Organic Species ◽  
Capacity Loss ◽  
Stable Performance ◽  
Redox Flow Cells ◽  
Selective Membranes

<p>The lack of suitable membranes for nonaqueous electrolytes limits cell capacity and cycle lifetime in organic redox flow cells. Using soluble, stable materials, we sought to compare the best performance that could be achieved with commercially available microporous separators and ion-selective membranes. We use organic species with proven stability to avoid deconvoluting capacity fade due to crossover and/or cell imbalance from materials degradation. We found a trade-off between lifetime and coulombic efficiency: non-selective separators achieve more stable performance but suffer from low coulombic efficiencies, while ion-selective membranes achieve high coulombic efficiencies but experience capacity loss over time. When electrolytes are pre-mixed prior to cycling, coulombic efficiency remains high, but capacity is lost due to cell imbalance, which can be recovered by electrolyte rebalancing. The results of this study highlight the potential for gains in nonaqueous cell performance that may be enabled by suitable membranes.</p>

Mn Substitution with Co in LiCo(1-X)MnxO2 Cathode Materials and their Charge-Discharge Characteristic

2012 ◽  
Vol 501 ◽  
pp. 133-137 ◽  
Author(s):  
Azira Azahidi ◽  
Kelimah Elong ◽  
Nurhanna Badar ◽  
Nurul Atikah Mohd Mokhtar ◽  
Rusdi Roshidah ◽  
...  
Keyword(s):  
Partial Substitution ◽  
Electrochemical Characteristics ◽  
Li Ion Batteries ◽  
X Ray Diffraction ◽  
Capacity Fading ◽  
Voltage Range ◽  
X Ray ◽  
Capacity Loss ◽  
Li Ion ◽  
The Stability

LiCoO2 has been used as a cathode material in commercial Li-ion batteries. This is due to advantageous properties of the LiCoO2 like ease of preparation and good electrochemical characteristics. However, the high cost and toxicity of Co has limited its use. Therefore, the substitution of Co in the LiCoO2 by non-toxic and inexpensive transition metallic element is needed. Mn is considered as one of the promising candidates to fulfill all the requirements. Partial substitution of Co by Mn has also been considered to enhance the stability of LiCoO2 lattice, minimize capacity fading and increase cycle life of the Li-ion battery. LiCo(1-x)MnxO2 (x= 0.1, 0.2, 0.3) were prepared by using a self-propagating combustion (SPC) method. X-ray diffraction (XRD) of the samples were carried out for phase analysis and showed that all the materials are pure. The samples were also analyzed using the Field Emission Scanning Electron Microscope (FESEM) to study its morphology and particle size. Finally cathodes were fabricated and assembled in an inert gas-filled fabrication box. Discharge profiles of the materials were carried out in the voltage range of 4.3 V – 3 V. The materials obtained were phase pure and improved the capacity fading of the materials compared to LiCoO2. All of the materials exhibited less than 10% capacity loss even though it does not improve the first cycle discharge capacity.

A standard for transmission electron spectroscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 530-531 ◽  
Author(s):  
Dennis Maher ◽  
David Joy ◽  
Peggy Mochel
Keyword(s):  
Thin Films ◽  
Electron Spectroscopy ◽  
Host Lattice ◽  
Single Element ◽  
Multicomponent Systems ◽  
Transmission Electron ◽  
Major Interest ◽  
Standard Specimens ◽  
Forms Of Carbon ◽  
Electron Energy Loss

A variety of standard specimens is needed in order to systematically investigate the instrumentation, specimen, data reduction and quantitation variables in electron energy-loss spectroscopy (EELS). Pure single element specimens (e.g. various forms of carbon) have received considerable attention to date but certain elements of interest cannot be prepared directly as thin films. Since studies of the first and second row elements in two- or multicomponent systems will be of considerable importance in microanalysis using EELS, there is a need for convenient standards containing these species. For many investigations a standard should contain the desired element, or elements, homogeneously dispersed through a suitable matrix and at an accurately known concentration. These conditions may be met by the technique of implantation.Silicon was chosen as the host lattice since its principal ionization energies, EL23 = 98 eV and Ek = 1843 eV, are well removed from the K-edges of most elements of major interest such as boron (Ek = 188 eV), carbon (Ek = 283 eV), nitrogen (Ek = 400 eV) and oxygen (Ek = 532 eV).

Analytical Electron Microscopy Study of Second-Phase Particles in 7075 and 7475 Aluminum Alloys

1985 ◽  
Vol 43 ◽  
pp. 348-349
Author(s):  
M. Raghavan ◽  
J. Y. Koo ◽  
J. W. Steeds ◽  
B. K. Park
Keyword(s):  
Aluminum Alloys ◽  
Silicon Oxide ◽  
Analytical Electron Microscopy ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Partial Substitution ◽  
Second Phase ◽  
X Ray ◽  
Second Phase Particles ◽  
Almost All

X-ray microanalysis and Convergent Beam Electron Diffraction (CBD) studies were conducted to characterize the second phase particles in two commercial aluminum alloys -- 7075 and 7475. The second phase particles studied were large (approximately 2-5μm) constituent phases and relatively fine ( ∼ 0.05-1μn) dispersoid particles, Figures 1A and B. Based on the crystal structure and chemical composition analyses, the constituent phases found in these alloys were identified to be Al7Cu2Fe, (Al,Cu)6(Fe,Cu), α-Al12Fe3Si, Mg2Si, amorphous silicon oxide and the modified 6Fe compounds, in decreasing order of abundance. The results of quantitative X-ray microanalysis of all the constituent phases are listed in Table I. The data show that, in almost all the phases, partial substitution of alloying elements occurred resulting in small deviations from the published stoichiometric compositions of the binary and ternary compounds.

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