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A set of LiNi 0.5 Mn 0.3 Co 0.2 O 2 /graphite lithium-ion cells underwent 750 charge-discharge cycles during about 8 months at 55 • C to upper cutoff potentials of 4.0, 4.1, 4.2, 4.3, and 4.4 V. The electrolyte in these cells was extracted using a centrifuge method and studied using gas chromatography/mass spectrometry to determine the changes to the solvents and by inductively coupled plasma-mass spectrometry to determine the changes to the salt content in the electrolyte. The negative electrodes from the cells were harvested and studied by micro-X-ray fluorescence to quantify the amount of transition metals which migrated from the positive electrode to the negative electrode during the testing. Emphasis is given to a detailed description of the quantitative methods used in the hope that others will adopt them in similar studies of different types of aged lithium-ion cells. The cells studied here initially had 1.1 molal LiPF 6 ethylene carbonate (EC): ethyl methyl carbonate (EMC) (3:7 by weight) electrolyte. The aged cells showed increasing amounts of dimethyl carbonate and diethyl carbonate created by transesterification as the upper cutoff potential increased. Only extremely small amounts of Mn, less than 0.1% of the total Mn in the positive electrode, were found on the negative electrode after this aggressive testing. Lithium-ion batteries are currently used in a wide range of applications: cell phones, power tools, vehicles and even grid energy storage.

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The common occurrence of Ca-and Nd-rich accessory minerals titanite, epidote, allanite and 37 apatite in calc-alkaline plutonic suites makes them ideal targets for in-situ tracing of the 38 temporal, chemical and isotopic evolution of tonalitic and granodioritic melts. The Sm-Nd 39 isotope composition of accessory phases from the calc-alkaline Bergell Pluton and the 40 peraluminous Novate leucogranite (central Alps) were investigated using laser ablation MC-ICPMS techniques. Grouping of individual LA-MC-ICPMS analyses produced average ε Nd 42 values with typical uncertainties of < 0.3 (2σ) epsilon units. SHRIMP dating of magmatic 43 allanite cores of epidote grains from a Bergell gabbro yielded a Th-Pb age of 32.4 ± 0.4 Ma, 44 which provides a new timing constraint on the emplacement of juvenile members within the 45 Bergell intrusive sequence. The Bergell bulk-rock mantle-crust isotopic mixing curve was 46 reproduced, demonstrating that integration of U-Th-rich accessory mineral Nd isotope 47 compositions with crystallisation age is capable of tracing the geochemical evolution of 48 magmatic systems over time. Crucially, the isotopic composition of the mantle end-member was successfully constrained by measurement of magmatic REE-epidote, highlighting the compositional versatility of accessory phases. The removal or addition of feldspar controls the Eu signature of both the bulk-rock and single minerals and therefore presents a unique trace element indicator of magmatic differentiation and assimilation processes in accessory minerals. Therefore the in-situ determination of age, Sm-Nd isotopes and trace elements in accessory minerals permits efficient and accurate reconstruction of complex magmatic processes in calc-alkaline plutonic suites. Sub-grain isotopic heterogeneity in magmatic monazite from the Novate leucogranite was identifiable by LA-MC-ICPMS analysis and emphasizes the additional value of a micro-analytical approach to understanding geological processes.

Static heating during intrusion of the Makhavinekh Lake Pluton (MLP) caused replacement of garnet in the adjacent country rocks (Tasiuyak Gneiss) by coronal assemblages of orthopyroxene + cordierite. Thermometry based on Al solubility in orthopyroxene, applied to relict garnet and neighbouring orthopyroxene, preserves a temperature gradient from 700 to 900°C at distances between 5750 and 20 m from the intrusion, reaffirming the robustness of this thermometry technique. Intracrystalline and intergranular variations of Al zoning in orthopyroxene are well-preserved, suggesting that little diffusional modification of Al growth zoning occurred. Maximum Al 2 O 3 in orthopyroxene ranges from c. 2.0 wt% at 5750 m from the intrusion to a maximum of 4.3 wt% at the contact. Individual orthopyroxene grains show decreasing Al from core to rim in samples < 500 m from the intrusion, while those at greater distances show an increase from core to rim. These features are interpreted with the aid of numerical models for conductive heat flow in the aureole. Coronas in samples close to the intrusion grew at high temperatures and along T-t paths dominated by cooling, so maximum Al content in orthopyroxene in these samples occurs in the cores of grains that grew during the earliest stages of garnet consumption. In contrast, the corona-forming reactions in rocks further from the contact proceeded along prograde heating paths, so maximum Al content in orthopyroxene occurs in the rims of grains that grew during the final stages of garnet consumption. These results document the ability of Al-in-orthopyroxene thermometry to preserve a detailed record of thermal histories in contactmetamorphic granulites; they suggest that similar intracrystalline and intergranular variations of Al zoning in orthopyroxene in regional granulites may also preserve portions of both the prograde and peak-T evolution.

Many studies of Li-ion cells examine compositional changes to electrolyte and electrodes to determine desirable or undesirable reactions that affect cell performance. Cells involved in these studies typically have a limited test lifetime due to the resource intensive and time-consuming nature of these experiments. Here, electrolyte and electrode analyses were performed on a large matrix of cells tested at various conditions and with various cycle lifetimes. The matrix included LiNi0.5Mn0.3Co0.2O2 (NMC532)/graphite and LiNi0.6Mn0.2Co0.2O2 (NMC622)/graphite pouch cells with excellent performing electrolyte mixtures, both cycling and storage protocols at 40 °C and 55 °C with both 4.3 V and 4.4 V upper cutoff potentials. This study presents post-test analysis (electrochemical impedance spectroscopy, differential voltage analysis, differential thermal analysis), electrolyte analysis (gas chromatography, quantitative nuclear magnetic resonance), and electrode analysis (micro X-ray fluorescence) for these cells after 3, 6, 9, and 12 months of testing. Many products and reactants, such as fraction of transesterification, gas production, transition metal dissolution appeared to have a constant rate of increase in this 12-month observation period. In most cases, results from cells after 3 to 6 months of testing could be used to reasonably estimate the status of the cells (electrolyte composition, gas production, transition metal dissolution) at 12 months.