Mechanical Effects Occurring inside Large Format 94 Ah Prismatic Lithium-Ion Cells at Different Bracing during Aging

Incorporation of solid state electrolytes (SSEs) leads to significant improvements in energy and power density of next generation lithium ion batteries (LIBs)[1]. SSEs also demonstrate better thermal stability than liquid electrolytes, which eventually enable enhancement in safety. However, dendrite growth in metal anodes during lithium deposition, and large resistance at anode/SSE interface, are major issues presently experienced by SSEs[2]. Similarly, at the positive electrode, volume change of the cathode particles during lithiation and delithiation can result in evolution of stress at the cathode/SSE interface, which may cause delamination, and subsequently impedance rise along with capacity fade[3]. All these issues at both anode/SSE and cathode/SSE interfaces prevent the implementation of SSEs in commercial LIBs. In the present research, the extent of mechanical degradation at the interface of cathode and ceramic SSE, and its impact on performance, will be investigated through computational techniques. Lithium ion cells with SSEs are fabricated with cathodes in a lithiated state, which corresponds to a discharged condition. During the first charge process, the cathodes experience delithiation, and shrink in size, which induces stress at the cathode/SSE interface. The amount of volume change in cathode, and subsequent stress generation, depends on the partial molar volume of lithium within the cathode material[4, 5]. Depending on the adhesion strength between the cathode and SSE, interfacial detachment may occur at the cathode/SSE interface[3]. Such loss of contact would lead to decrease in electro-chemically active surface area, and effectively increase the interfacial resistance. A computational model has been developed to capture the volume change in cathode and evolution of stress at cathode/SSE interface. This technique has also been extended to investigate the propensity of interfacial delamination and subsequent deterioration in cell performance. The impact of rate of operation, depth of discharge, and number of cycles, on the cathode/SSE interfacial delamination induced performance decay, will be elucidated in the present research.

Silicon (Si)‐based negative electrodes have attracted much attention to increase the energy density of lithium ion batteries (LIBs) but suffer from severe volume changes, leading to continuous re‐formation of the solid electrolyte interphase and consumption of active lithium. The pre‐lithiation approach with the help of positive electrode additives has emerged as a highly appealing strategy to decrease the loss of active lithium in Si‐based LIB full‐cells and enable their practical implementation. Here, the use of lithium squarate (Li2C4O4) as low‐cost and air‐stable pre‐lithiation additive for a LiNi0.6Mn0.2Co0.2O2 (NMC622)‐based positive electrode is investigated. The effect of additive oxidation on the electrode morphology and cell electrochemical properties is systematically evaluated. An increase in cycle life of NMC622||Si/graphite full‐cells is reported, which grows linearly with the initial amount of Li2C4O4, due to the extra Li+ ions provided by the additive in the first charge. Post mortem investigations of the cathode electrolyte interphase also reveal significant compositional changes and an increased occurrence of carbonates and oxidized carbon species. This study not only demonstrates the advantages of this pre‐lithiation approach but also features potential limitations for its practical application arising from the emerging porosity and gas development during decomposition of the pre‐lithiation additive.

Recent years have witnessed a tremendous increase in contamination levels of heavy metals in the agricultural soils due to the uncontrolled release of chemicals and toxic substances from various human activities. The transfer of heavy metals to the groundwater and humans through the various food chains may cause serious health problems. Therefore, continuous evaluation of heavy metals content in the agricultural soil is important to control the spread of pollution, to preserve the soil quality, and to protect human health. In this study, we determined the content of heavy metals (V, Cr, Mn, Co, Ni, Cu, Zn, and Pb) in the agricultural soils of Kafr El-Zayat city, Egypt using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES). In ICP-OES, the soil samples were digested using a mixture of concentrated nitric and hydrochloric acids at a ratio of 1: 3 and heating on a hot plate at a temperature of 120 ℃ for few hours. This method of sample preparation was not efficient in extracting the total metal content in the soils and the results had to be corrected for using reference materials. In LA-ICP-MS, the soil samples were prepared in a form of rigid pellets using a hydraulic press. The accuracy of the analyses was examined by analyzing reference materials and comparing the observed results to the published concentration values. The concentrations of heavy metals determined by the ICP-OES were found to be 90.14 ppm for Zn, 57.90 ppm for Cu, 75.3 ppm for Ni, 115.18 ppm for Cr, 32.75 ppm for Co, and 11.49 ppm for Pb. Meanwhile, the concentrations of heavy metals as measured by LA-ICP-MS were found to be 100.60 ppm for Zn, 69.78 ppm for Cu, 90.8 ppm for Ni, 116.42 ppm for Cr, 41.38 ppm for Co, and 18.24 ppm for Pb. The concentrations of V, Cr, and Ni exceeded the concentration levels of the Canadian soil quality guidelines, which indicate the contamination of the examined agricultural soils with these elements

Fast charging of lithium ion cells is an important hurdle to overcome for the increased penetration of electric vehicles into the transportation market. During the fast charging of lithium ion cells with today’s current negative electrode active materials, namely graphite, lithium metal plating has a high likelihood of occurring. This occurs as most of the lithiated graphite potential is within 100 mV of Li/Li+ potential where a small polarization can result in lithium metal plating on the negative electrode. This plating leads to safety issues, and capacity fade, among other things. As the lithium metal is plated on the graphite negative electrode it can either become isolated and inactive, resulting in a loss of active lithium and capacity fade in the cell, or the lithium remains active during cell cycling where it may either migrate into the negative electrode over time or travel to the cells positive electrode during discharge.To date most lithium metal plating identification techniques, involve destructive physical analysis. The current study presents an electrochemical approach and technique which may identify reversible lithium metal plating on graphite negative electrodes during fast charging of lithium ion cells.

The conventional approaches of estimating the lifecycle of lithium-ion batteries utilize battery ageing models combined with data from accelerated ageing tests. Despite the prevalent use of these accelerated techniques in battery research over the years, there still exists a lack of consistency in the testing parameters and methodology. Particularly in cycle ageing tests, the rest period between cycles is typically selected without a standard criterion and is generally minimised to facilitate higher cycle throughput. Although this parameter has been considered to have minimal influence on the test results1, a recent study2 has demonstrated that cycle-to-cycle relaxation may have a significant impact on the cell cycle life, even though the investigated cells were cycled in otherwise identical conditions. This work aims to expand on the findings presented in2, by investigating the underlying mechanism of this behaviour, using X-ray CT imaging, forensic and post-mortem analysis.In this study, commercially available cylindrical lithium-ion cells were subjected to prolonged cycling with different rest periods between cycles. For the relaxation time after discharge, three time constants were selected, namely 1min, 10min and 60min, while the relaxation period after charge was kept constant at 1min. The cells were cycled at 10°C between the charge/discharge voltage cut-off limits specified by the manufacturer, with 0.3C/1C current rate for charge/discharge respectively. A clear correlation between relaxation time and cell degradation was observed in the cycling results, as the cells cycled with longer rest periods exhibited higher capacity fade (Fig.1(a)). Non-invasive diagnostic analysis conducted with differential voltage (DVA) and incremental capacity (ICA) revealed increased losses of lithium inventory and active material in the longer relaxation test cases. As the main relaxation time was after discharge, when the cells were at a low SOC and in sub-ambient temperature (10°C), calendar ageing effects are expected to be negligible, which indicates the presence of a different underlying mechanism responsible for the observed degradation pattern.At the end of the cycle ageing test, X-ray computed tomography (XCT) scans were obtained for all the tested cells, and one cell per test case was selected to be dismantled for autopsy and visual inspection. The XCT images revealed severe deformations in the jelly roll of all tested cells, in the form of kinks located in the innermost layers, between the cell's hollow core and the positive current collector tab (Fig.1(b)). Furthermore, the cell structural integrity appears to deteriorate as the relaxation period increases, since more jelly roll layers appear to be affected in the 10min and 60min test cases (Fig.1(b)). Upon dismantling, significant electrode delamination was observed in the innermost electrode areas for all test cases (Fig.1(c)-(e)), which was inherently linked to the jelly roll deformation. For the cells cycled with 60min relaxation, a bright coloured passivation layer was detected in the mid to outer layers of the negative electrode (Fig.1(e)-(f)), implying the potential occurrence of lithium plating3. Furthermore, the opposing parts of the cathode electrode corresponding to the location of the passivation layer in the anode exhibited a unique wave-like deformation pattern (Fig.1(f)), which indicates that these jelly roll regions where subjected to high mechanical stresses during cycling. The autopsy results support the preliminary diagnostic conclusions, as the presence of the covering layer and the morphological changes in the electrodes can lead to loss of active lithium and active material, due to local passivation and particle cracking.Overall, this study demonstrates that longer cycle-to-cycle relaxation periods cause higher mechanical and electrochemical stresses within the tested lithium-ion cells, which can even lead to the formation of local passivation layers, affecting their electrochemical performance and structural integrity. This effect, which has not been previously reported, does not appear to be present in all cells, as a preliminary investigation conducted with three different commercial cells of similar format did not exhibit the same trend. Although the underlying mechanisms responsible for the results presented in this study needs to be investigated further, the potential influence of relaxation on the cycling behaviour of lithium-ion cells needs to be considered in the design and interpretation of accelerated ageing tests. Reichert, D. Andre, A. Rösmann, P. Janssen, H. G. Bremes, D. U. Sauer, S. Passerini, and M. Winter, Journal of Power Sources, 239 45-53 (2013). G. Darikas, A. Barai, M. Sheikh, P. Miller, M. Amor-Segan, and D. Greenwood, in "Electrochemical Society Meeting s 242", p. 2590-2590. The Electrochemical Society, Inc., 2022. A. J. Smith, Y. Fang, A. Mikheenkova, H. Ekström, P. Svens, I. Ahmed, M. J. Lacey, G. Lindbergh, I. Furó, and R. W. Lindström, Journal of Power Sources, 573 233118 (2023). Figure 1

Due to the small quantity of most of the extracted human urinary stone samples, there is an urgent need for an analytical technique that is able to perform a multi‐elemental quantitative analysis for a small fraction of these samples. In the present work, a few milligrams of different types of urinary stones were microwave digested in ultra‐pure nitric acid, and the elemental determination was achieved by total reflection X‐ray fluorescence (TXRF). The elements P, S, Ca, Fe, Cu, Zn, Se, and Sr were detected in most of the different stones. However, the trace elements: K, Ti, V, Cr, Mn, Ni, As, Pb, and U were also found in a certain number of samples. Furthermore, inductively coupled plasma optical emission spectrometry (ICP‐OES) was used and the elements Mg, Ti, Mn, Cu, Zn, and Cd were determined. A good agreement between the results of TXRF and ICP‐OES was obtained with respect to the elements Ti, Mn, Cu, and Zn. Cadmium and magnesium were only determined by ICP‐OES. More attention was given to the existence and the spectral interference of As‐K α and Pb‐L α as well as As‐K β and Br‐K α in a limited number of urinary stones. Based on the analysis of variance and Pearson's correlation analysis, an additional statistical analysis study was performed in terms of quantified elements and the types of urinary stones. Calcium has a remarkable positive correction with Ni, Zn, and P, whereas a negative correlation was found with K, S, and Cu. Based on the hierarchical cluster analysis, the square Euclidean showed four main groups of urinary stones starting with high to trace amounts of calcium oxalate. Furthermore, the squared Euclidean showed further subgroups of the urinary stones. The role of certain elements in terms of forming or inhabiting the urinary stone formation was discussed. Uranium was determined in a limited number of urinary stones using TXRF and ICP‐OES. The origin of the uranium may be the drinking and groundwater. Uranium could be accumulated in the urinary stones from these sources. In addition, the divalent uranium compounds can deposit on the surface of hydroxyapatite crystal, which is one of the main compounds in the urinary stones.

Fireworks produce spectacular visual effects through the combustion and explosion of pyrotechnic compositions, which are made up of oxidizers, fuels, colorants and binders. To improve safety and environmental protection, the Chinese national standard GB 10631-2013 prohibits the use of arsenic, mercury compounds and zirconium powder in pyrotechnic compositions of all firework products, and lead compounds in specific categories. Currently, the testing methods in GB/T 21242 are qualitative and often suffer from matrix interference. This study aims to establish an inductively coupled plasma optical emission spectrometry (ICP-OES) method for the rapid and accurate quantitative detection of prohibited components in pyrotechnic compositions, as the application of ICP-OES in fireworks quality control has not been explored previously. The research successfully developed an ICP-OES method. Analytical-grade reagents and standard solutions were used, and the ICP-OES operating conditions were optimized. Specific analytical lines (As 189.042 nm, Hg 194.227 nm, Pb 220.353 nm, Zr 343.823 nm) were selected to avoid interference. Different sample preparation methods were applied to effect charge and bursting charge. The calibration curves showed good linearity (correlation coefficients ≥ 0.9990), with low detection limits (0.013-0.031 μg/mL). Interference analysis confirmed negligible inter-element and matrix interference. Precision tests showed relative standard deviations of 1.64% -2.71%, and accuracy tests had recovery rates of 98.5% -101%. The established ICP-OES method enables the simultaneous determination of arsenic, lead, mercury, and zirconium in pretreated pyrotechnic compositions. With its simplicity, rapidity, low detection limits, and high precision and accuracy, this method provides a reliable approach for the quantitative analysis of prohibited components in fireworks, contributing to the quality control of fireworks products.

Objective: To establish the method for determination of tungsten and insoluble compounds in the air of workplace by inductively coupled plasma optical emission spectrometry (ICP-OES) . Methods: The tungsten and insoluble compounds were digested by microwave digestion apparatus using nitric acid and hydrofluoric acid, detected by ICP-OES. Results: The linearity of tungsten and insoluble compounds (as tungsten) were good at the range of 0.16-100.0 μg/ml, the minimum quantitation concentration was 0.11 mg/m(3), the recovery was ranged from 81.9%-97.1%, the RSD of intra-and inter-batch precision were 0.5%-2.5% and 1.2%-4.4%, respectively. Conclusion: The determination method meet the requirement of analysis and apply to the determination of tungsten and insoluble compounds in the air of workplace.

Imaging the distribution of nutrient elements and the uptake of toxic metals in industrial hemp and white mustard with laser-induced breakdown spectroscopy

Ion chromatography was used to detect levels of copper and zinc in blood plasma from renal dialysis patients on continuous ambulatory peritoneal dialysis (CAPD) and haemodialysis (HD). The developed method used cobalt as an internal standard and when combined with the standard additions method improved the overall precision of the results by between -0.3 and 6.0% and -0.8 and 5.7% for copper and zinc, respectively. The method was compared with inductively coupled plasma optical emission spectrometry (ICP-OES) and the results indicated no significant difference between the two methods with or without an internal standard. Without an internal standard, tcalc was 0.869 with a tcrit of 2.201 (n = 12, P = 0.05) and with an internal standard, tcalc was 0.189 compared to a tcrit of 2.201 (n = 12, P = 0.05). The copper and zinc levels in blood plasma in both dialysis groups were not significantly different to the copper and zinc levels in blood plasma of the control patients. A convenient method of analysis of trace elements in blood such as ion chromatography with UV/VIS detection is useful for determining whether inorganic elements may be disrupted in the body due to changes in the state of health.

This proposed method regulated the determination of platinum, palladium, ruthenium, rhodium, iridium and gold in platinum-group ores by nickel sulfide fire assay—inductively coupled plasma optical emission spectrometry (ICP-OES) combined with ultrasound extraction for the first time. The quantitative limits were 0.013–0.023μg/g. The samples were fused to separate the platinum-group elements from matrix. The nickel sulfide button was then dissolved with hydrochloric acid and the insoluble platinum-group sulfide residue was dissolved with aqua regia by ultrasound bath and finally determined by ICP-OES. The proposed method has been applied into the determination of platinum-group element and gold in large amounts of ultrabasic rocks from the Great Dyke of Zimbabwe.

Laser Induced Breakdown Spectroscopy (LIBS) method is introduced as a novel approach in this work to study catalyst deactivation of V2O5/γ‐‐Al2O3 for gas‐phase dehydration of glycerol and producing acrolein. The LIBS results of V2O5/γ‐Al2O3 samples are compared with those data that are obtained by Inductively Coupled Plasma Optical Emission Spectrometry (ICP‐OES). Experimental data of LIBS data specify that line intensities of vanadium are decreased by deactivation of V2O5/γ‐Al2O3 catalyst. A comparison between the results of LIBS test as well as ICP‐OES analysis shows that the amount of vanadium is decreased in the catalyst. Moreover, coke formation changes the surface of the catalyst. The results of deactivation of V2O5/γ‐Al2O3 are also compared with Pd/C catalyst deactivation.

Oxygen bomb combustion of biological samples for inductively coupled plasma optical emission spectrometry

Matrix effects were evaluated on the determination of Dy, Eu and Yb used as sheep faecal markers by inductively coupled plasma optical emission spectrometry (ICP-OES) with axially- and radially-viewed configurations. The samples were prepared with microwave-assisted acid digestion using an oven with closed vessels. The analytical performances of the two ICP-OES instruments were compared using Mg II/Mg I intensity ratios at different operating conditions. The values obtained using the axially-viewed ICP were 6.5 (1.3 kW and 0.7 l min−1) and 4.8 (1.0 kW and 0.9 l min−1). These values were higher than those determined using radially-viewed ICP-OES, 5.2 and 2.5, respectively. Under all operating conditions and for all elements measured, the detection limits obtained with the axially-viewed configuration were at least three-fold better, but were more critically affected by incremental background emission increases at a higher plasma power and lower nebulization gas flow rate. The accuracy of the Dy, Eu and Yb determinations in acid-digested faecal samples by axially- and radially-viewed ICP-OES was verified using the INAA technique, and a paired t-test showed that all results were in agreement at a 95% confidence level.

Palladium (Pd) and platinum (Pt) are extensively used as catalysts in the petrochemical and automotive industries, and due to high demand for them on the market, their recycling from spent supported catalysts is clearly needed. To assess the content of Pd and Pt in catalysts in order to establish their commercial value or to evaluate the recovery efficiency of technologies used for recycling, reliable analytical methods for determination of these elements are required. Spectrometric methods, such as inductively coupled plasma optical emission spectrometry (ICP-OES) and graphite furnace atomic absorption spectrometry (GFAAS) are powerful tools that can be employed for the determination of Pd and Pt in various sample matrices. However, these methods allow only the injection of liquid samples. In this regard, the digestion of solid sample by microwave-assisted acid extraction procedures at high pressures and temperatures is often used. In this study, a microwave acid digestion method was optimized for the extraction of Pd and Pt from spent catalysts, using a four-step program, at a maximum 200 °C. The resulting solutions were analyzed using ICP-OES, at two different wavelengths for each metal (Pd at 340.458 and 363.470 nm, and Pt at 265.945 and 214.423 nm, respectively) and using GFAAS (Pd at 247.64 nm, Pt at 265.94 nm). Five types of spent catalyst were analyzed and the standard deviations of repeatability for five parallel samples were less than predicted relative standard deviations (PRSD%) calculated using Horvitz’s equation for all the analyzed samples.