Publications by authors named "Matthew J Lacey"

The galvanostatic intermittent titration technique (GITT) is considered the go-to method for determining the Li diffusion coefficients in insertion electrode materials. However, GITT-based methods are either time-consuming, prone to analysis pitfalls or require sophisticated interpretation models. Here, we propose the intermittent current interruption (ICI) method as a reliable, accurate and faster alternative to GITT-based methods.

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In the field of lithium-based batteries, there is often a substantial divide between academic research and industrial market needs. This is in part driven by a lack of peer-reviewed publications from industry. Here we present a non-academic view on applied research in lithium-based batteries to sharpen the focus and help bridge the gap between academic and industrial research.

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Two water-soluble binders of carboxymethyl cellulose (CMC) and sodium alginate (SA) have been studied in comparison with N-methylpyrrolidone-soluble poly(vinylidene difluoride-co-hexafluoropropylene) (PVdF-HFP) to understand their effect on the electrochemical performance of a high-voltage lithium nickel manganese oxide (LNMO) cathode. The electrochemical performance has been investigated in full cells using a Li Ti O (LTO) anode. At room temperature, LNMO cathodes prepared with aqueous binders provided a similar electrochemical performance as those prepared with PVdF-HFP.

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TiO -coating of LiNi Mn O (LNMO) by atomic layer deposition (ALD) has been studied as a strategy to stabilize the cathode/electrolyte interface and mitigate transition metal (TM) ion dissolution. The TiO coatings were found to be uniform, with thicknesses estimated to 0.2, 0.

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Three-electrode measurements are valuable to the understanding of the electrochemical processes in a battery system. However, their application in lithium-sulfur chemistry is difficult due to the complexity of the system and thus rarely reported. Here, we present a simple three-electrode cell format with relatively good life time and minimum interference with the cell operation.

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This study demonstrates the application of AlO coatings for the high-voltage cathode material LiNi Mn O (LNMO) by atomic layer deposition. The ultrathin and uniform coatings (0.6-1.

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Functional binders constitute a strategy to overcome several challenges that lithium-sulfur (Li-S) batteries are facing due to soluble reaction intermediates in the positive electrode. Poly (ethylene oxide) (PEO) and poly (vinylpyrrolidone) (PVP) are in this context a previously well-explored binder mixture. Their ether and amide groups possess affinity to the dissolved sulfur species, which enhances the sulfur utilization and mitigates the parasitic redox shuttle.

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Objective: We sought to evaluate the impact of pulmonary embolism (PE) response teams (PERTs) on all consecutive patients with PE.

Background: Multidisciplinary PERTs have been promoted for the management and treatment of (PE); however, the impact of PERTs on clinical outcomes has not been prospectively evaluated.

Methods: We prospectively studied 220 patients with computed tomography (CT)-confirmed PE between January, 2019 and August, 2019.

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Operando X-ray diffraction (XRD) is a valuable tool for studying secondary battery materials as it allows for the direct correlation of electrochemical behavior with structural changes of crystalline active materials. This is especially true for the lithium-sulfur chemistry, in which energy storage capability depends on the complex growth and dissolution kinetics of lithium sulfide (LiS) and sulfur (S) during discharge and charge, respectively. In this work, we present a novel development of this method through combining operando XRD with simultaneous and continuous resistance measurement using an intermittent current interruption (ICI) method.

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Background: Coronary embolism is a rare and potentially fatal phenomenon that occurs primarily in patients with valvular heart disease and atrial fibrillation. There is a lack of consensus regarding the diagnosis, treatment, and management of coronary embolism, leaving management at the discretion of the treating physician. Through this review, we aim to establish a better understanding of coronary embolism, and to identify treatment options - invasive and non-invasive - that may be used to manage coronary embolism.

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An operando electrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D) with simultaneous in situ electrochemical impedance spectroscopy (EIS) has been developed and applied to study the solid electrolyte interphase (SEI) formation on copper current collectors in Li ion batteries. The findings are backed by EIS simulations and complementary analytical techniques, such as online electrochemical mass spectrometry (OEMS) and X-ray photoelectron spectroscopy (XPS). The evolution of mass and the mechanical properties of the SEI are directly correlated to the electrode impedance.

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In this work, three types of polymers based on ε-caprolactone have been synthesized: poly(ε-caprolactone), polystyrene-poly(ε-caprolactone), and polystyrene-poly(ε-caprolactone--trimethylene carbonate) (SCT), where the polystyrene block was introduced to improve the electrochemical and mechanical performance of the material. Solid polymer electrolytes (SPEs) were produced by blending the polymers with 10-40 wt% lithium bis(trifluoromethane)sulfonimide (LiTFSI). Battery devices were thereafter constructed to evaluate the cycling performance.

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We report here a water-based functional binder framework for the lithium-sulfur battery systems, based on the general combination of a polyether and an amide-containing polymer. These binders are applied to positive electrodes optimised towards high-energy electrochemical performance based only on commercially available materials. Electrodes with up to 4 mAh cm capacity and 97-98 % coulombic efficiency are achievable in electrodes with a 65 % total sulfur content and a poly(ethylene oxide):poly(vinylpyrrolidone) (PEO:PVP) binder system.

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Efficient, reversible lithium intercalation into graphite in ether-based electrolytes is enabled through a protective electrode binder, polyacrylic acid sodium salt (PAA-Na). In turn, this enables the creation of a stable "lithium-ion-sulfur" cell, using a lithiated graphite negative electrode with a sulfur positive electrode, using the common DME:DOL solvent system suited to the electrochemistry of the lithium-sulfur battery. Graphite-sulfur lithium-ion cells show average coulombic efficiencies of ∼99.

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Frequent and continuous determination of battery internal resistance by a simple current-interrupt method enables the visualisation of cell behaviour through the creation of resistance "maps", showing changes in resistance as a function of both capacity and cycle number. This new approach is applied here for the investigation of cell failure in the lithium-sulfur system with Li electrode excesses optimised towards practically relevant specifications.

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PEO, used either as a binder or a polymer coating, and PEGDME, used as an electrolyte additive, are shown to increase the reversible capacity of Li-S cells. The effect, in all three cases, is the same: an improved solvent system for the electrochemistry of sulfur species and suppression of cathode passivation on discharge. This constitutes a novel interpretation of the mechanistic behaviour of polyethers in the Li-S system, and sheds new light upon several previous studies.

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