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Two main goals for the industrial, slurry‐based electrode processing are a high process speed and the maximum possible material efficiency. This makes an increased drying rate and active material share favorable, but both are limited by adverse effects on the electrode quality. The adverse effects of fast drying are associated with the migration of binder. In this article, the slurry properties of water‐based graphite slurries are manipulated using a synthetic, layered silicate as additive. The influence of the polymer‐particle composite network on the viscosity, adhesion strength, and cell performance is investigated. By addition of a small amount of additive (0.5 wt% of the dry electrode), the binder migration is mitigated up to a drying rate of 6 g m−2s−1for graphite anodes with ≈4.2 mAh cm−2(corresponding with 30 s drying time) leading to a possible increase of eight times the process speed compared to drying with 0.75 g m−2s−1if adverse effects on the tortuosity of the electrodes can be solved. In this work, a combination of additive usage is pointed out with a multilayer approach and first insights are provided in how the binder migration may be mitigated to gain structurally optimized fast‐dried electrodes without losses in electrode quality. With the use of additives, binder migration during drying of water‐based battery electrode slurries can be mitigated. In this article, purposefully manipulated slurry properties are connected with the microstructure formation for increasing drying rate and give insights how to possibly improve the electrode quality by aimed use of additives in terms of adhesion strength and electrochemical performance of the electrodes.

This study identifies the critical aspects of binder distribution and mechanical integrity in aqueously processed LNMO cathodes, employing a comprehensive approach involving surface characterization techniques, adhesion strength testing, and electrochemical characterization. The investigation includes the use of the Washburn and Sessile Drop methods for surface free energy analysis, revealing key insights into the interfacial free energy of adhesion between cathode constituents. The results explain the formation of carbon-binder-domains and their impact on adhesion strength, with a particular focus on the conductive additives’ (CA) surface area. The study demonstrates the effectiveness of reducing CA surface area and employing alternative conductive additives, such as vapor-grown carbon fibers (VGCF), in improving adhesion strength and mitigating capacity fade attributed to delamination during cycling. Furthermore, the research emphasizes the role of heat treatment beyond the melting point of the polyvinylidene fluoride (PVDF) latex binder, showcasing its influence on wetting and enhancing mechanical integrity. The presented methodology provides a valuable tool for predicting and optimizing binder distribution, offering insights into improving the overall performance and reliability of aqueously processed cathodes for advanced lithium-ion batteries.

Sodium‐ion batteries are considered to be one of the most promising postlithium batteries on the verge of commercialization. The electrode processing is expected to be similar to lithium‐ion batteries. However, the producibility and material processing challenges of potential electrode materials for anodes and cathodes are poorly understood. For industrial electrode production, a deep understanding of the processing of electrode materials with different particle morphologies is of great importance. In particular, the correlation between the process conditions and the electrode properties needs to be investigated further to understand the complex interactions between the battery slurry materials, the binder system, the drying process, and the microstructure formation. One promising anode material is hard carbon. The water‐based processing of hard carbon slurries presented in this article shows that the drying behavior is strongly interconnected with the particle size and particle interactions in the drying electrode. This study shows that all the hard carbons investigated do not exhibit binder migration at moderate drying rates. Even at very high drying rates (9 g m−2s−1, 12 s drying time), an increase in adhesion force of up to 39% is observed for comparatively smaller particles compared to the adhesion force at lower drying rate. Producibility and material processing challenges of potential electrode materials for anodes and cathodes for sodium‐ion batteries are poorly understood. This study shows that all hard carbons investigated do not exhibit binder migration at moderate drying rates. Even at very high drying rates (12 s drying time), increase in adhesion force of up to 39% is observed for comparatively smaller particles.

Porous, nanostructured particles ensure the wetting of electrolyte up to the particle core and shortened diffusion paths, which is relevant not only for lithium‐ion batteries but also for postlithium systems like sodium‐ion batteries. The porous structure leads to a high C‐rate capability. However, compared to conventional compact NCM, porous NCM shows a reduced adhesion force but no or only slight negative influence on C‐rate capability by binder migration at higher drying rates. Herein, a multilayer concept is used to increase the adhesion force with equal or better electrochemical performance compared to single‐layer electrodes. Compact particles of high volumetric energy density and porous particles with high C‐rate capability are combined in a simultaneously coated multilayer electrode. Multilayers with compact NCM toward the current collector and porous NCM with reduced binder content toward the separator side show an about 16‐times higher adhesion force at lower drying rate and an about ten‐times higher adhesion force at increased drying rate compared to electrodes produced of porous NCM only. The specific discharge capacity of the multilayers is increased by 88% at the lower and 67% at the higher drying rate for a discharge rate of 3C compared to a single layer with compact NCM. Multilayer architecture is used to increase the adhesion force with better electrochemical performance. The multilayer electrodes show 16‐times higher adhesion force compared to electrodes produced of porous NCM622 only. The specific discharge capacity of the multilayers is increased by 88% for a discharge rate of 3C compared to a single layer with compact NCM622.

Previous investigations on porous Li(NixCoyMnz)O2(NCM) particles with shortened diffusion paths and an enlarged interface between active material and electrolyte show improved rate capability and cycle stability compared to compact particles. Due to the additional intragranular porosity of the active material, also the pore structure of the overall electrode, and as consequence, the ionic transport in the pore phase is altered. In addition, the particle morphology influences the ohmic contact resistance between the current collector and electrode film. These effects are investigated using impedance spectroscopy in symmetrical cells under blocking conditions. The ionic resistance and the tortuosity of the electrodes are determined and analyzed by a transmission line model. Tortuosity is higher for porous particles and increases more during calendering. This limits the options to densify these electrodes to the same level as with compact particles. In a further approach, the method is used to explain the drying related performance differences of these electrodes. At higher drying rates, the contact and the ionic resistance of electrodes with compact particles increases more strongly as for electrodes with porous particles. These investigations provide new insights into the ion transport behavior and enable a better understanding of the impact of the electrode processing condition.

Glass is one of the most important high-performance materials used for scientific research, in industry and in society, mainly owing to its unmatched optical transparency, outstanding mechanical, chemical and thermal resistance as well as its thermal and electrical insulating properties. However, glasses and especially high-purity glasses such as fused silica glass are notoriously difficult to shape, requiring high-temperature melting and casting processes for macroscopic objects or hazardous chemicals for microscopic features. These drawbacks have made glasses inaccessible to modern manufacturing technologies such as three-dimensional printing (3D printing). Using a casting nanocomposite, here we create transparent fused silica glass components using stereolithography 3D printers at resolutions of a few tens of micrometres. The process uses a photocurable silica nanocomposite that is 3D printed and converted to high-quality fused silica glass via heat treatment. The printed fused silica glass is non-porous, with the optical transparency of commercial fused silica glass, and has a smooth surface with a roughness of a few nanometres. By doping with metal salts, coloured glasses can be created. This work widens the choice of materials for 3D printing, enabling the creation of arbitrary macro- and microstructures in fused silica glass for many applications in both industry and academia.

Porous, nanostructured Li(NixCoyMn)O2(NCM) achieves an improvement in the fast‐charging capability and the durability of lithium‐ion batteries. This improvement is attributed to an extended electrolyte—active material interface, where the electrochemical reactions take place and thus shorter diffusion paths inside the active material particles are necessary for charge transfer. Due to the porous particle morphology, new processing challenges arise compared to compact solid NCM. Herein, the properties of the slurries and the electrodes made of the two active materials and, in particular, the influence of the drying process on the binder distribution, are comparatively investigated. For the same composition of the slurries, a significantly lower dependence of adhesion force and discharge capacity at higher C‐rates on the drying rate is shown when using porous, nanostructured particles instead of solid particles. Binder migration and thus an inhomogeneous concentration distribution of the polyvinylidene fluoride binder is less pronounced for these electrodes during faster drying. Cell tests with half cells show that after increasing the drying rate by more than 350%, the discharge capacity of the electrodes consisting of solid NCM is reduced by about 63% at 5C while for the electrodes made of porous material no reduction is measured. Herein, the properties of electrodes made of two different active materials at increasing drying rates and the binder distribution are comparatively investigated. When using porous nanostructured particles instead of solid particles, a significantly lower binder migration and a very low dependence of the discharge capacity at higher C rates on the drying rate are observed.

A rapid manufacturing method for fabrication of 3D ceramic parts will be presented. The structural information is printed by ink jet in powder layers of 80 µm thickness. Different granulated powders can be used, such as zirconia and alumina if they show good flow ability. After printing the structures a heating process takes place. After these the parts can be picked out from the powder bed. The manufactured parts can be impregnated with epoxy. Another option is the infiltration with ceramic slurries and glass with sintering to higher density. The sintering process has been studied and the shrinkage and material properties evaluated. The interrelationship between the raw material qualities, infiltration media and the sinter parameters as well as the material-specific properties such as density and stability will be presented. The manufacturing method is used for fabrication of moulds and cores for casting processes. Otherwise the process can be used for fast fabrication of models and prototypes. The possibilities to use these methods for implant manufacturing will be shown. A cost analysis has been performed comparing direct manufacturing of small batches of components to mould injection processes.

A rapid manufacturing method for fabrication of 3D ceramic parts will be presented. The structural information is printed by ink jet in powder layers of 80 µm thickness. Different granulated powders can be used, such as zirconia and alumina if they show good flow ability. After printing the structures a heating process takes place. After these the parts can be picked out from the powder bed. The manufactured parts can be impregnated with epoxy. Another option is the infiltration with ceramic slurries and glass with sintering to higher density. The sintering process has been studied and the shrinkage and material properties evaluated. The interrelationship between the raw material qualities, infiltration media and the sinter parameters as well as the material-specific properties such as density and stability will be presented. The manufacturing method is used for fabrication of moulds and cores for casting processes. Otherwise the process can be used for fast fabrication of models and prototypes. The possibilities to use these methods for implant manufacturing will be shown. A cost analysis has been performed comparing direct manufacturing of small batches of components to mould injection processes.

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4-Benzyl-4-methyl-2-phenyl-5(4H)-oxazolone (1) forms with the chloro bridged compounds [R3PMCl2]2(M = Pt, Pd) the complexes Cl2Pt(PR3)(l) (R = Et, nBu) and Cl2Pd(PEt3)(l). The enantiomeric pure C2-symmetric CMe2bridged bis(oxazolones) 5 and 6 have also been employed which give with PdCl2the chelate complexes 13 and 14. The X-ray structural determination of Cl2P d[O-C (O)-CMe2-N=C-CMe2-C=N-CMe2-C (O)-O ] (10) shows that one of the methyl group of the CMe2bridge is located near the palladium atom. This can also be detected in the 1H NMR spectrum.

The extended process chain starting from slurry mixing up to the operative lithium‐ion battery requires a deep understanding of each individual process step and knowledge of the interaction of the different process steps with each other. In particular, the intertwining of slurry mixing and drying determines the microstructure of the electrode, which in turn affects the performance of the cell. Herein, a scalable multilayer approach is used to tailor electrodes with improved mechanical and electrochemical properties, which disclose their advantages especially at high drying rates. Cryogenic broad ion beam scanning electron microscopy (Cryo‐BIB‐SEM) micrographs are used to reveal the influences of different process parameters, like slurry formulation, mixing device, and properties of the active material on the intrinsic network between active particles and binders in graphite‐based anode slurries. By a chosen combination of these slurries in a multilayer electrode, a tenfold acceleration of the drying time with favorable mechanical and electrochemical properties for full cells derived from these anodes is demonstrated. A multilayer approach is used to tailor electrodes with improved mechanical and electrochemical properties, with advantages at high drying rates. Cryogenic broad ion beam scanning electron microscopy (Cryo‐BIB‐SEM) micrographs reveal influences of different process parameters on the intrinsic network between active material and binders in graphite‐based anode slurries that enable accelerated drying rates.

Reactions of 2-phenyl-4-R-5(4H)-oxazolones (R = Me, CH2Ph, CHMeEt) with [(η⁵-C5Me5)IrCl2]2 afforded the cyclometallated complexes (η⁵-C5Me5)(Cl)Ir(L) (1−3) [L = 2-phenyl-4-R-5(4H)-oxazolone(C-o,N)]. 2-Phenyl-5(4H)-oxazolone reacts with [(η⁵-C5Me5)IrCl2]2 and palladium(II) acetate to give complexes with a C-o,N-bridging oxazolone [(η⁵-C5Me5)(Cl)Ir]2(μ-Cl)(μ-L-H⁺) (4) and Pd3(μ-ac)5(μ-L-H⁺) (5). 2-Phenyloxazolone anions were added to the π ligands of [(η⁵-C6H7)Fe(CO)3]⁺ and [(η⁷-C7H7)Cr(CO)3]⁺ to give the adducts 6−11. Dipeptide derivatives 12−18 were obtained by reaction of 1, 2 and by reaction of the adduct 6 from [(η⁵-C6H7)Fe(CO)3]⁺; and the anion of 2-phenyloxazolone with α-amino acid esters. These reactions may be used for the labelling of peptides. Saponification of 15−18 yields the organometallic substituted peptide acids 19−22. Their dianions (deprotonation of COOH and peptide amide) were used as ligands towards (Ph3P)2PtCl2 to yield the bimetallic complexes 23−25. The structures of 4, 5, 9 and 10 were determined by X-ray diffraction.

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Plasma iron turnover has been evaluated in the growing rat. Consistent data were obtained with the intravenous injection of radioiron in the form of ferrous sulfate or ferric citrate. Plasma iron turnover changed as a function of plasma iron concentration. Only part of this effect in the rat was due to the different rates of clearance of mono- and diferric transferrin, the latter having a higher iron delivery rate in vivo. An additional effect was shown to relate to the rate of red cell production. With decreased production, the effect of plasma iron on plasma iron turnover was reduced, whereas with increased erythropoiesis there was an additional increment in plasma iron turnover for any increase in plasma iron. Since this effect was observed when increased iron demands were due to an increase in erythroid precursors in the marrow but not in the circulating blood, it is attributed to limitations in iron flow to the marrow. This suggests that erythroid marrow activity and the adequacy of iron supply when studied by ferrokinetic techniques can best be defined by the response curve relating plasma iron concentration to plasma iron turnover.

The behavior of rat transferrin has been investigated employing acrylamide gel electrophoresis and isoelectric focusing. In vitro trace labeling with iron chelates at 30 min was 93%–98% effective, whereas binding by simple ferric salts was reduced to 71%–76%. Complete and specific binding of 59FeSO4by the iron binding sites of transferrin was demonstrated after in vitro or in vivo addition of ferrous ammonium sulfate in pH 2 saline up to the point of iron saturation. In vitro the radioiron transferrin complex in plasma was stable and its iron had a negligible exchange with other transferrin binding sites over several hours. The distribution of radioiron added in vitro or through absorption was shown to be random between the binding sites of slowand fasttransferrin molecule. Iron distribution among body tissues was similar for mono- and diferric transferrin iron and was not affected by the site distribution of iron on the transferrin molecule. The only important aspect of transferrin iron binding was the more rapid tissue uptake of iron in the diferric form as compared to monoferric transferrin. Additional in vivo effects on internal iron exchange were produced by changes in the iron balance of the animal. In the iron loaded animal, monoferric transferrin injected into the plasma was rapidly loaded by iron from tissue and thereby converted to diferric transferrin. Injection of diferric transferrin in the iron deficient animal was associated with a rapid disappearance from circulation of the original complex and a subsequent appearance of monoferric transferrin as a result of iron returning from tissues. These observations support the concept that plasma iron behaves as a single pool except that diferric iron exchange occurs at a more rapid rate than does monoferric iron exchange.

The reactions of Na2PdCl4, [(nBu3P)PtCl2]2, [(nBu3P)PdCl2]2and [(C8H14)2RhCl]2/CO with diphenylmethylene glycine esters (L1) or 2-phenyl-4-R-oxazolones (L2) afford the complexes (nBu3P)(Cl)2Pt(L1), (OC)2(Cl)Rh(L1), Cl2Pd(L1)2and (nBu3P)(Cl)2M(L2) (M = Pd, Pt), respectively. The X-ray structural determination of Cl2Pd(L1)2and the 1H and 13C NMR spectra show a close proximity of the ortho phenyl-H-atom to the metal; the complexes are precursors for ortho metallation.

A reduction of the inactive components can increase the energy density and reduce production cost of Li‐ion batteries. But an effective reduction of the binder amount also negatively affects the adhesion of the electrode. Herein, slot‐die coating of a primer layer for Li‐ion anodes is investigated. It is shown that the use of a primer layer with only 0.3 g m−2can increase the adhesive force by the factor of 5 as well as the cell performance for anodes with low binder content. The process limits for a stable, defect‐free primer coating are investigated at coating speeds of up to 550 m min−1. The limits coincide both for a setup without vacuum box and with vacuum box with theory‐based equations. By using a vacuum box, the minimum wet film thickness can be reduced by half. The use of primer layers is a promising way to improve the properties of lithium‐ion battery electrodes. This study considers the process window for industrial‐related slot‐die coating of primer at very high coating speeds. A vacuum‐stabilized coating bead enables cost‐effective production of very thin wet film thicknesses at coating speeds of over 550 m min−1.

The use of thicker electrodes can contribute to a reduction in cell costs. However, the properties of the electrode must be kept in view to be able to meet the performance requirements. Herein, the possibility of simultaneous multilayer slot die coating is investigated to improve the electrode properties of medium‐ and high‐capacity anodes. The stable coating window of the two‐layer slot die coating process is investigated to produce property‐graded multilayer electrodes. Electrodes with different styrene–butadiene rubber (SBR) gradients are investigated with regard to adhesive force and electrochemical performance. An increase in the adhesive force of up to 43.5% and an increase in the discharge capacity is observed. The pregrading of additives in Li‐ion battery electrodes during coating can provide significant benefits to their properties. Herein, it is shown that the graded two‐layer anodes can be produced by simultaneous multilayer coating with 2 mAh cm−2as well as high‐energy electrodes with 8 mAh cm−2. These graded anodes show a better adhesive force up to 43.5 % and a higher discharge capacity.

When fabricating battery electrodes, their properties are strongly determined by the adjusted drying parameters. This does not only affect their microstructure in terms of adhesion, but also influences cell performance. The reason is found to be the binder transported to the surface during drying. Herein, it is shown that when thicker electrodes are processed, new challenges arise. On the one hand, loss of adhesion associated with certain drying conditions becomes a more serious problem; on the other hand, cracking occurs at a certain drying rate and with increasing electrode thickness. The drying process of electrodes for lithium‐ion batteries of different thicknesses is investigated. The dependency of adhesion, crack formation, and drying kinetics on drying conditions is shown and limiting factors are proposed. Increased drying rates and area loadings lead to an adhesion loss which can be compensated by different processing routes to some extent as presented here.