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Monolithic open macroporous carbons of 80-85 % porosity are obtained from pyrolyzing oxidized high internal phase templated poly(dicyclopentadiene) foams. The macropores void diameters of the resulting carbon foams can be ajusted between 87 and 2.5 mikrometer simply by changing the surfactant amount used in the preparation of the precursor foams. The resulting porous carbon materials are charcterized by a carbon content >97%, an electronic conductivity of up to 2800 S/m, a Young's modulus of up to 2.1 GPa and a specific surface area of up to 1200 m2/g.

Advanced anode material designs utilizing dual phase alloy systems like Si/FeSi2 nano-composites show great potential to decrease the capacity degrading and improve the cycling capability for Lithium (Li)-ion batteries. Here, we present a multi-scale characterization approach to understand the (de-)lithiation and irreversible volumetric changes of the amorphous silicon (a-Si)/crystalline iron-silicide (c-FeSi2) nanoscale phase and its evolution due to cycling, as well as their impact on the proximate pore network. Scattering and 2D/3D imaging techniques are applied to probe the anode structural ageing from nm to μm length scales, after up to 300 charge-discharge cycles, and combined with modeling using the collected image data as an input. We obtain a quantified insight into the inhomogeneous lithiation of the active material induced by the morphology changes due to cycling. The electrochemical performance of Li-ion batteries does not only depend on the active material used, but also on the architecture of its proximity. Alloy systems like Si/FeSi2 nano composites have great potential as stable anode materials in Li-ion batteries, but their characterization at different scales and throughout their ageing remains challenging. Here the authors use scattering and 2D/3D imaging techniques combined with modeling to elucidate morphology changes upon cycling of the anode.

Operando magnetic susceptibility measurements of the cathode material LiNi 0.6 Mn 0.2 Co 0.2 O 2 during repetitive electrochemical cycling enable a continuous and volume sensitive monitoring of the transition metal oxidation states. Upon charging a simultaneous oxidation of Co 2+ - and Ni 2+ -ions down to a Li-content of x = 0.53 occurs, followed by an exclusive oxidation of Ni 3+ -ions for 0.53 > x > 0.21 . In the low Li concentrations regime x 0.21 Co 3 + -ions were found to be involved in the charge compensation process although a sufficient amount of Ni 3+ -ions is still present in the cathode material. While the oxidation process of Ni 2+ - and Co 2+ -ions is reversible, the Ni 3+ - and Co 3+ -ion oxidation process is found to be at least partially irreversible.

Wheel defects on railway wagons have been identified as an important source of damage to the railway infrastructure and rolling stock. They also cause noise and vibration emissions that are costly to mitigate. We propose two machine learning methods to automatically detect these wheel defects, based on the wheel vertical force measured by a permanently installed sensor system on the railway network. Our methods automatically learn different types of wheel defects and predict during normal operation if a wheel has a defect or not. The first method is based on novel features for classifying time series data and it is used for classification with a support vector machine. To evaluate the performance of our method we construct multiple data sets for the following defect types: flat spot, shelling, and non-roundness. We outperform classical defect detection methods for flat spots and demonstrate prediction for the other two defect types for the first time. Motivated by the recent success of artificial neural networks for image classification, we train custom artificial neural networks with convolutional layers on 2-D representations of the measurement time series. The neural network approach improves the performance on wheels with flat spots and non-roundness by explicitly modeling the multi sensor structure of the measurement system through multiple instance learning and shift invariant networks.

A brief report is given on recent studies of the atomistic processes during charging of battery cathode material LixCoO2 by means of magnetometry and positron annihilation. A set-up for operando magnetometry is implemented which, for the first time, allowed to continuously monitor the distinct variation of the magnetic susceptibility χ of LixCoO2 which occurs during consecutive charging and discharging cycles. The variation of χ with Li+ content in the concentration range 1>x≥0.77 arises from a variation of the electronic density of states and from electronic correlation effects. The χ (x)-behaviour for xx)-variations in this concentration regime. First measurements on LixCoO2 thin-films performed at the positron beam line NEPOMUC of FRM II at the Heinz Maier-Leibnitz neutron source will be presented.

The variation of the structural and electronic properties of LixCoO2 upon electrochemical Li-extraction was studied over wide range concentration of 1 ≥ x ≥ 0.20 by means of SQUID magnetometry. The ex-situ measurements performed for 13 different compositions were supplemented by operando measurements of the magnetic moment during repetitive electrochemical in-situ cycling of the Li-concentration. From the temperature-dependent measurements an effective magnetic susceptibility with Curie–Weiss behavior and an additional temperature-independent part due to Pauli and Van Vleck magnetism is derived. The increase of the temperature-independent susceptibility with Li-extraction reflects a concomitant increase of the electronic density of states and, in addition, indicates an Anderson-type of the occurring nonmetal–metal transition. The effective magnetic moment reveals that only a fraction of 30% of the charge is transferred to Co upon Li-extraction indicating a complex oxidation behavior involving oxygen. Exposure to ambient atmosphere gives rise to a complete oxidation of Co. The results on the structural variation with Li-concentration are compared with accompanying measurements by X-ray diffraction and by our recent defect studies by positron annihilation.

Operando measurements of the magnetic susceptibility χ during electrochemical charging of commercially used battery electrode materials are implemented in a superconducting quantum interference device magnetometer. The capability of this measurement set-up to study electronic and chemical processes in the electrode is exemplified by Li x CoO 2 cathodes, for which reversible variations of their susceptibility χ by more than a factor of 1.5 could be continuously monitored. From the variation of χ with Li-ion concentration x for 1>x≥0.77, where Pauli paramagnetism prevails, a linear increase of the electronic density of states with Li extraction is derived, indicating that the occurring nonmetal-metal transition is of Anderson-type. For x

Different environmental conditions affect tree senescence by different patterns of carbohydrate concentrations and have specific impact on the dissection of the photosynthetic apparatus. A proactive cultivation of Mediterranean broadleaf species, including oaks, has been suggested to fill possible temporal and spatial gaps in forestry created by Climate Change in Central Europe in the future. Climate can affect trees in several different ways, e.g., by modulating the course of leaf senescence. Senescence-associated processes, like regulation of carbohydrates and changes in chlorophyll fluorescence under drought stress conditions were studied with leaf tissue of drought-tolerant downy oak (Quercus pubescens). Two months of consistent drought stress in a frost-free greenhouse led to significantly earlier senescence and significant increased amounts of soluble sugars in the leaves of the drought-stressed group in comparison to a well-watered control group. Similar sugar accumulation was observed in trees outdoors, after exposure to frost. In contrast to monocarpic plants the accumulation of free sugars is neither triggering leaf senescence, nor is it a side effect of age-depending changes in Q. pubescens. Instead, sugar accumulation is induced by abiotical factors, like drought and frost. Furthermore, we suggest that the senescence process in the absence of drought stress or frost depends on the source status of the leaf, which, in term, is a function of light (through photosynthesis) and night temperature (through respiration). Contents of the storage metabolite starch decreased during late summer in all three groups. Drought-stressed plants showed a decline of the connectivity of photosystem II antenna, reflected as the L-band in the chlorophyll fluorescence induction curves, and stronger correlations between the declines in the capacity of photosynthetic dark reactions and electron transport-associated chlorophyll fluorescence parameters. We conclude that the disassembly of single parts of the photosynthetic apparatus during leaf senescence is a uniform process, but the onset of this process depends on abiotical environmental factors.

In 1997, Goodenough and coworkers (1) discovered phospho-olivines LiMPO4 (M = Fe, Mn, Ni, Co) as promising positive electrode material for rechargeable lithium-ion batteries. Due to their flat voltage profile, high theoretical capacity (170 mAh*g-1 for LiFePO4), excellent thermal stability and environmental friendliness they attracted attention for both portable devices and automotive applications. Most research activities focused on the improvement of the electrochemical performance of LiFePO4, since LiMnPO4suffers from worse lithium-ion diffusion kinetics and Jahn-Teller distortion of its crystal lattice (2). It is believed that the formation of solid solutions (3) between LiFePO4 and LiMnPO4 (LiFexMn1-xPO4) remarkably improves the electronic conductivity. This strategy seems auspicious, since the higher potential of LiMnPO4 (4.1V vs. Li/Li+) compared to LiFePO4 (3.5V vs. Li/Li+) leads to a superior energy density of the resulting lithium-ion battery. Therefore, we report a microwave solvothermal synthesis of phospho-olivines LiMPO4(M= Fe, Mn, Co, Ni) and mixtures thereof within 10 minutes of reaction time. It is common for increasing the electronic conductivity of phospho-olivines to use one of the following problem-solving approaches: Coating with a conducting phase (4), minimizing of the particles in size (5) and doping with positive divalent\trivalent metal ions and\or fluorine (6). Morphology of the samples is analyzed by scanning electron microscopy (SEM) as shown in figure 1. Additionally all powders are analyzed by X-ray powder diffraction (XRD), energy dispersive X-ray analysis (EDX), cyclic voltammetry (CV) and galvanostatic cycling (CC) experiments. The occurrence of Fe and Mn in the phospho-olivine and their influence on the cell performance will be discussed (cf. figure 2). Furthermore, Mg is incorporated into the lattice and its influence on electrochemical behavior will be shown as well (cf. figure 3). Acknowledgement Herbert Quandt Foundation is gratefully acknowledged for funding. References 1. A.K. Padhi, K.S. Nanjundaswamy, J.B. Goodenough, J. Electrochem. Soc., 144, 1188 (1997). 2. J. Hong, F. Wang, X. Wang, J. Graetz, J. Power Sources, 196, 3659 (2011). 3. C.-K. Back, R.-Z. Yin, Y.-S. Kim, J. Electrochem. Soc., 160, A1551 (2013). 4. H.C. Shin, W.I. Cho, H. Jang, Electrochim. Acta, 52, 1472 (2006). 5. I. Bilecka, A. Hintennach, M. D. Rossell, D. Vie, P. Novák, M. Niederberger, J. Mater. Chem., 21, 5881 (2011). 6. Y. Huang, Y. Xu, X. Yang, Electrochim. Acta, 113, 156 (2013). Figure 1

Thermal degradation products in lithium-ion batteries result mainly from hydrolysis sensitivity of lithium hexafluorophosphate (LiPF 6 ). As organic carbonate solvents contain traces of protic impurities, the thermal decomposition of electrolytes is enhanced. Therefore, resulting degradation products are studied with nuclear magnetic resonance spectroscopy (NMR) and gas chromatography mass spectrometry (GC–MS). The electrolyte contains 1 M LiPF 6 in a binary mixture of ethylene carbonate (EC) and diethylene carbonate (DEC) in a ratio of 1:2 (v/v) and is aged at ambient and elevated temperature. The impact of protic impurities, either added as deionized water or incorporated in positive electrode material, upon aging is investigated. Further, the influence of different housing materials on the electrolyte degradation is shown. Difluorophosphoric acid is identified as main decomposition product by NMR-spectroscopy. Traces of other decomposition products are determined by headspace GC–MS. Acid–base and coulometric titration are used to determine the total amount of acid and water content upon aging, respectively. The aim of this investigation is to achieve profound understanding about the thermal decomposition of one most common used electrolyte in a battery-like housing material.

This study reports on a novel approach to fabrication of carbon-sulfur composite material and demonstrates its application as cathode for Li–S batteries. Firstly, highly porous carbon material has been prepared by exploiting PMMA colloidal crystal arrays as sacrificial template and subsequently mixing with elemental sulfur at 155 °C. The resulting carbon-sulfur composite cathode material possess very high intrinsic surface area, conductivity and has been found to demonstrate as high as 1600 mAh g−1 capacity in 1st discharge cycle and about 300–400 mAh g−1 in 50th discharge cycle.

In this paper we present the first results for the characterization of highly porous cathode materials with pore sizes below 1 μm for Lithium Sulfur (Li–S) batteries by Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. A novel cathode material of porous carbon films fabricated with colloidal array templates has been investigated. In addition, an electrochemical characterization has been performed aiming on an improved correlation of physical and chemical parameters with the electrochemical performance. The performed NEXAFS measurements of cathode materials allowed for a chemical speciation of the sulfur content inside the cathode material. The aim of the presented investigation was to evaluate the potential of the NEXAFS technique to characterize sulfur in novel battery material. The long term goal for the characterization of the battery materials is the sensitive identification of undesired side reactions, such as the polysulfide shuttle, which takes place during charging and discharging of the battery. The main drawback associated with the investigation of these materials is the fact that NEXAFS measurements can usually only be performed ex situ due to the limited in situ instrumentation being available. For Li–S batteries this problem is more pronounced because of the low photon energies needed to study the sulfur K absorption edge at 2472 eV. We employed 1 μm thick Si 3 N 4 windows to construct sealed argon cells for NEXAFS measurements under ultra high vacuum (UHV) conditions as a first step towards in situ measurements. The cells keep the sample under argon atmosphere at any time and the X-ray beam passes mainly through vacuum which enables the detection of the low energy X-ray emission of sulfur. Using these argon cells we found indications for the presence of lithium polysulfides in the cathode films whereas the correlations to the offline electrochemical results remain somewhat ambiguous. As a consequence of these findings one may state that measurements for battery material characterization are preferably to be performed completely in situ with the electrochemical measurements taking place simultaneously in order to obtain clear and unambiguous results.

The defect specific technique of positron–electron annihilation is utilized in an appropriate electrochemical cell for operando monitoring of vacancy-type defect formation which occurs in battery electrodes upon charging, using the cathode material LiNi1/3Mn1/3Co1/3O2 as a case study. The variation of the positron lifetime with charging-induced Li ion extraction indicates the formation of divacancies and vacancy agglomerates in a progressive amount as well as a reordering of vacancy agglomerates to one-dimensional vacancy chains at the end of charging. A remarkable correlation of the charging-induced variation of the positron lifetime with that of Li ion diffusion data in the literature has been found.

The preparation of open-cell macroporous membranes made by the ring opening metathesis polymerization (ROMP) of a mixture of norbornene and dicyclopentadiene, and their basic applicability as separators in lithium-ion batteries, is discussed. Cyclic voltammetry (CV) measurements of negative electrodes (graphite) and positive electrodes (LiCoO2 ) are performed and the results prove the absence of parasitic decomposition reactions within the membrane at high oxidative or reductive potentials. Furthermore, LiCoO2 /Li half cell cycling studies of 100 charging/discharging cycles reveal that the newly disclosed separator and conventional commercial polyolefin based separators have similar performance. These results demonstrate that a potential weakness in the newly disclosed separator, namely residual double bonds present in the polymer network, does not limit the use of this material as a separator in lithium-ion batteries.

The paper describes two ways for increasing the specific energy of Li-ion batteries in order to extend the EV driving range. The first way is the development of a Si/graphite anode. This anode consists of n-Si/graphite composite particles, a special cellulose based binder and a 3D-collector (POLYMET®). With this anode a specific capacity of ∼1,200 mAh/g is obtained. More than 500 cycles with this anode and prelithiation is reachable. As a second way, for higher specific energy, Mg-ion systems are addressed. The main problem of Mg-ion cells is the anode. Mg and also graphite are forming together with the electrolyte (except Grignard type electrolytes) surface layers, which have no Mg2+ conductivity. By changing the electrolyte, however, an intercalation/deintercalation into graphite can be shown for the first time. Based on this innovation Mg-ion cells with MgxV2O5 as cathode are possible having a cell voltage of ∼3.7 V.

This article takes stock of where philosophy of technology is at, and where it has been since the so-called ‘empirical turn’ announced around the millennial turn. The article both discusses recent advances and suggests concrete ways of making progress in specific topics, especially regarding the philosophical study of technical artefacts. The article proposes to pursue philosophy of technology under three headings: the nature of artefacts, the concept of design, and the notion of use. The paper illustrates two specific ways in which philosophical discussion of such notions can and will make progress: one, by bringing a much greater degree of systematicity to answers that philosophers give to individual questions thrown up by these three notions, and two, by drawing in to a greater degree philosophical expertise acquired and developed in current foundational analytic philosophy, above all metaphysics and the philosophy of language. The paper’s two goals are connected: only by enlisting ‘foundational’ philosophy can we bring a degree of systematicity to contemporary analytic philosophy of technology, and its future.

Historically, philosophical inquiries into ethics have repeatedly aligned with inquiries into architecture and, especially, the human city. Be it Plato’s writings on the polis or Augustine’s reflections on the two cities in his Civitate Dei, philosophical attention to matters at the heart of architectural practice seem not lacking (Illies and Ray 2009, p. 1199n.1). It may be surprising, then, that contemporary philosophy lacks its own sustained attempt at an ethics of architecture. With few notable exceptions (such as Scruton 1995), architecture does not receive the contemporary philosophical attention it deserves. We may inquire why this is so, but also how to remedy this. One way of remedy would be to work one’s way towards an ethics of architecture by starting from a layman’s perspective on architecture. Another mode of remedy would seek to scrutinize extant ethical debates within architectural theory and see what can be done to improve these debates from a philosophical point of view.

Operando magnetic susceptibility measurements on the Li x Ni 1 / 3 Mn 1 / 3 Co 1 / 3 O 2 cathode material during repetitive electrochemical cycling were performed, enabling a continuous and bulk sensitive monitoring of the charge compensation process. Upon charging and Li extraction down to the Li contents of x = 1/3, exclusively Ni undergoes oxidation in two consecutive steps, namely, Ni 2 + → Ni 3 + for x > 2/3 and Ni 3 + → Ni 4 + for 2/3 > x > 1/3 with a continuous transition in between. In the regime of low Li concentrations x

Es ist bekannt, dass das Personal in geriatrischen Pflegeheimen auserordentlich stark psychisch belastet ist. In fruheren Untersuchungen wurde gezeigt, dass in Pflegebetrieben mit gezielten, psychologischen Interventionsmassnahmen gute Ergebnisse erzielt werden konnen. Die Idee liegt also nahe, eine psychologische Beratungsstelle fur das Personal zu institutionalisieren. Andererseits ist bekannt, dass psychologische Beratung haufig aufgrund von Angst, Unsicherheiten und Vorurteilen nicht in Anspruch genommen wird. Die vorliegende Studie untersucht die potenzielle Nachfrage nach psychologischer Beratung und versucht zu ermitteln, aus welchen Grunden eine Inanspruchnahme verweigert wird. In einem geriatrischen Pflegeheim wurde eine Erhebung mittels Fragebogen unter allen Mitarbeitenden durchgefuhrt (N = 234). Die Bedarfsermittlung erfolgte anhand einer funfstufigen Likert-Skala von 1 (sehr tief) bis 5 (sehr hoch). Die qualitativen Daten wurden zu Clustern zusammengefasst. Der Gesamtmittelwert wurde mit M = 2,88 angegeben. Die Befragten sehen also lediglich „etwas“ Bedarf fur eine institutionalisierte Beratungsstelle. Nur 44% aller Befragten gaben an, eine psychologische Beratungsstelle im Bedarfsfall auch tatsachlich aufzusuchen zu wollen. Die Nicht-Inanspruchnahme wird vorwiegend mit Misstrauen, Angst und Scham begrundet. Die Ergebnisse decken sich mit den aus der Literatur bekannten Ergebnissen bezuglich Aversionen gegenuber psychologischer Interventionen. Die Implementierung einer psychologischen Beratungsstelle fur das Personal ist somit moglicherweise mit Vorurteilen behaftet, weshalb es sich empfiehlt, diesen Prozess mit ver-trauensbildenden Masnahmen zu begleiten.

Attempting to achieve the high diversity of training goals in modern competitive alpine skiing simultaneously can be difficult and may lead to compromised overall adaptation. Therefore, we investigated the effect of block training periodization on maximal oxygen consumption (VO2max) and parameters of exercise performance in elite junior alpine skiers. Six female and 15 male athletes were assigned to high-intensity interval (IT, N = 13) or control training groups (CT, N = 8). IT performed 15 high-intensity aerobic interval (HIT) sessions in 11 days. Sessions were 4 x 4 min at 90-95% of maximal heart rate separated by 3-min recovery periods. CT continued their conventionally mixed training, containing endurance and strength sessions. Before and 7 days after training, subjects performed a ramp incremental test followed by a high-intensity time-to-exhaustion (tlim) test both on a cycle ergometer, a 90-s high-box jump test as well as countermovement (CMJ) and squat jumps (SJ) on a force plate. IT significantly improved relative VO2max by 6.0% (P < 0.01; male +7.5%, female +2.1%), relative peak power output by 5.5% (P < 0.01) and power output at ventilatory threshold 2 by 9.6% (P < 0.01). No changes occurred for these measures in CT. tlim remained unchanged in both groups. High-box jump performance was significantly improved in males of IT only (4.9%, P < 0.05). Jump peak power (CMJ -4.8%, SJ -4.1%; P < 0.01), but not height decreased in IT only. For competitive alpine skiers, block periodization of HIT offers a promising way to efficiently improve VO2max and performance. Compromised explosive jump performance might be associated with persisting muscle fatigue.

Concerning prospective energy storage, lithium-ion batteries (LIBs) are one of the most outstanding technologies due to their high energy density as well as great cycle stability. To increase their operational lifetime, thermal degradation of the most common conductive salt lithium hexafluorophosphate LiPF6 (1) should be avoided. Therefore, it’s crucial to minimize traces of protic impurities resulting from e.g. organic carbonates. In fact, the products of the endothermic equilibrium of LiPF6 are preferably formed at higher temperatures, leading to the formation of hydrofluoric acid (HF) and subsequently to further degradation of electrolyte components. (2) LiPF6 (s) LiF (s) + PF5(g) [1] PF5 (g) + H2O (l) → O=PF3(g) + 2 HF (l) [2] Lux et al. (3) followed the HF formation in LiPF6 containing electrolytes by spectroscopic ellipsometry of SiO2 layers. As we reported recently (4), SiO2 probably promotes the degradation of LiPF6 in organic carbonate based electrolytes. Herein, we report about the decomposition of 1M LiPF6 in a binary mixture of ethylene carbonate and diethylene carbonate in a ratio of 40:60 (w/w) at ambient and elevated temperature (cf. table 1). Degradation products are studied by nuclear magnetic resonance spectroscopy (NMR, cf. figure 1), gas chromatography mass spectrometry (GC-MS) and headspace GC-MS (HS-GC-MS). Acid-base and coulometric titration are used to determine the total amount of acid and water content upon aging, respectively. Ultraviolet-visible (UV-Vis) spectroscopy is used to follow the color change of the electrolyte (cf. figure 2). The influence of protic contamination, different housing materials and added active materials on the electrolyte aging is shown. Acknowledgement VOLKSWAGEN VARTA Microbattery Forschungsgesellschaft and Herbert Quandt Foundation are gratefully acknowledged for funding. References 1. K. Xu, Chem. Rev., 104, 10 (2004). 2. C. L. Campion, W. Li, B. L. Lucht, J. Electrochem. Soc., 152, A2327 (2005). 3. S. F. Lux, I.T. Lucas, E. Pollak, S. Passerini, M. Winter, R. Kostecki, Electrochem. Commun., 14, 47 (2012) 4. P. Handel, G. Fauler, K. Kapper, M. Schmuck, C. Stangl, F. Fischer, F. Uhlig, S. Koller, J. Power Sources, 267, 255 (2014). Figure 1

The unabated demand of cost-effective and high performance battery systems compells research groups to look for further improvements of energy storage systems around the world. Lithium-ion batteries seem to be an appropriate solution for this energy issue, but on the other hand extraordinary breakthroughs within the next years are not to be anticipated. Furthermore, lithium-ion batteries still suffer from serious safety concerns. Considering properties such as a rather low reduction potential (-2.36 V vs. SHE), high specific capacity (3380 mAh/cc), low equivalent weight and moreover, sufficient safety due to a non-dendritic metal deposition, magnesium-ion batteries appear to be competitive to lithium-ion batteries [1]. Since organic, aprotic electrolyte systems create a passivation layer on the Mg metal surface preventing a reversible Mg-deposition and dissolution, corrosive electrolytes such as Grignard compounds have to be used [2]. However, research focuses on the development of Mg-battery systems with an operational voltage of 3V Grignard electrolytes do not provide. A strategy to achieve the ambitious 3V goal is the development of intercalation/insertion compounds such as tin or graphite and replacement of corrosive electrolytes by organic ones [3]. From literature it is well known that the Mg-intercalation into graphite is impossible showing even solvated intercalation [4, 5]. However, in this contribution we want to shed light on the intercalation behavior of Mg into graphite with a broad range of electrochemical and spectroscopical analysis methods showing a non destructive and reversible magnesiation and de-magnesiation of a common graphite electrode with organic, aprotic electrolytes (cf. figure 1, figure 2 and figure 3). References: [1] P. Saha, M.K. Datta, O.I. Velikokhatnyi, A. Manivannan, D. Alman, P.N. Kumta. Progress in Materials Science 66, 2014, 1-86. [2] Z. Lu, A. Schechter, M. Moshkovich, D. Aurbach. Journal of Electroanalytical Chemistry, 1999, 203–217. [3] N. Singh, T.S. Arthur, C. Ling, M. Matsui, F. Mizuno. ChemComm, 2012. [4] M. Kawaguchi, A. Kurasaki. Chem. Commun., 2012, 48, 6897–6899. [5] Y. Maeda, Ph. Touzain. Electrochimica Acta, 1988, 1493-1497. Figure 1

Lithium-ion batteries have developed into most advanced battery systems, e.g. laptops and mobile phones. LiCoO2 is a typical intercalation battery cathode material. However, reversible charge-discharge cycling of LiCoO2 is only possible down to 50% of the available Li-ions since further removal of Li-ions drastically reduces the capacity and cycle stability. The formation of vacancy-type defects during the charging process in LixCoO2 battery cathodes was investigated by XRD and position life-time spectroscopy and Doppler broadening of positron-electron annihilation (PA) radiation as defect specific techniques [1]. Li+-extraction, which in a battery mode corresponds to charging, was performed at 293 K under electrochemical control in a 3-electrode test-cell with a Maccor Series 4000 battery tester. The composition of the lithium-ion electrode material used was: 88wt.% LiCoO2 particles, 7 wt.% carbon black as conducting agent, 5 wt.% binder material (polyvinylidene difluoride hexafluoropropylene copolymer). Structural analysis of the electrode samples was performed by means of X-Ray diffraction using a Bruker D8 Advance diffractometer in Bragg-Brentano geometry with Cu-Kα radiation. Diffractograms were measured in the 2-Theta angle range from 150to 1300and were analysed by Rietveld refinement with the programs FULLPROF [2] and X'PertHighScorePlus (Panalytical). For positron annihilation measurements a positron source (22NaCl) was sandwiched between two identical LiCoO2 electrode samples. Positron lifetime measurements were performed with a fast-fast spectrometer with a time resolution of 221 ps. The spectra were analysed by using the program pfposfit [3]. Doppler broadening (DB) measurements were performed in a coincidence setup with two high purity Ge detectors.with energy resolution for the 511 keV annihilation γ-line in the detector system corresponds to ca. 0.88keV (FWHM). Both the Doppler broadening S parameter as well as the positron lifetime component τ1 exhibit a characteristic variation with increasing amount of Li+-extraction; the S-parameter and τ1 first increases upon decreasing x from 1 to 0.6. Further Li+-extraction causes a decrease of S and τ1 (x = 0.55), followed by a re-increase for x

Ionic liquids are of great importance for electrodeposition of metals, which can't be deposited from aqueous electrolytes due to their negative standard potentials. In this paper non-woven polymers were coated with aluminium by electrodeposition from 1-ethyl-3-methyl-imidazolium chloride and subsequently established as 3D current collectors for lithium-ion batteries. We investigated the long-term stability of the ionic liquid (IL) for electrodeposition of aluminium under process-oriented conditions. The degradation products were analysed by headspace gas chromatography-mass spectrometry, pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) and 1H/13C nuclear magnetic resonance spectroscopy (NMR). The main decomposition products derived from thermal degradation, especially from cleavage of an alkyl chain and were identified as chloromethane, dichloromethane, methylimidazole, ethylimidazole and deprotonated 1-ethyl-3-methylimidazole.

Fruher erhielt man auf die zentrale Frage „Weshalb setzt der Kunde meine Produkte und nicht die eines Wettbewerbers ein?“die gangige Antwort „Weil wir Funktionalitat und Qualitat kostengunstiger als unser Wettbewerber anbieten konnen“. Heute stellt man eine gesamtheitliche Betrachtung der wertschopfenden Leistungsprozesse, angefangen vom Erkennen des Anforderungsprofils eines Produktes bis hin zur Entsorgung, mit den entsprechenden Losungen als Differenzierungskriterium in den Vordergrund.

Um praktische Erfahrungen und Kenntnisse fur den industriellen Einsatz zu gewinnen, wurde ein Versuchsaufbau zur automatischen Direktmontage von Leitungen in Lottechnik realisiert. Der Versuchsaufbau dient der Erprobung und Integration des entwickelten Verdrillverfahrens im Gesamtsystem.

Der bei der Direktmontage von Leitungen erforderliche Arbeitsablauf benotigt die Bearbeitung der Leitungsenden im Werkzeug. Die bei der Lottechnik durchzufuhrenden Operationen sind das Ablangen, Abisolieren und Verdrillen der Leitungsenden. Das Verdrillen der Leitungsenden beeinflust die Qualitat der Verbindung wesentlich und ist deshalb zu optimieren. Bei verschiedenen Litzen (Leitungsaufbau, Anzahl der Einzeldrahte) ergeben sich bei konstanten Verdrillparametern gravierende Unterschiede bei den Verdrillergebnissen. Eine zuverlassige, moglichst homogene Verdrillung der Leitungsenden kann mit konstanten Verdrillparametern nicht gewahrleistet werden. Fur die automatische Direktmontage von Leitungen in Lottechnik ist deshalb die Entwicklung eines geeigneten Verdrillverfahrens notwendig, das zum einen die optimale Werkzeugintegration und zum anderen das definierte Verdrillen der Leitungsenden ermoglicht.

Das fur die Direktmontage von Leitungen relevante Anwendungsgebiet liegt bei Produkten, deren Verdrahtung durch die Montage von Einzelleitungen erzeugt wird. Zur Ermittlung der notwendigen Daten erfolgte die Analyse von 67 verschiedenen Produkten, die Auswertung von Datenmaterial einer Marktumfrage sowie anhand Ergebnissen aus zahlreichen Expertengesprachen. Die Analyse zeigt, das sich das relevante Produktspektrum uber viele Branchen erstreckt. Deshalb wurden die Produkte, unabhangig von ihrer Branchenzugehorigkeit, zu Produktgruppen zusammengefast.

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