Applications of advanced metrology for understanding the effects of drying temperature in the lithium-ion battery electrode manufacturing process

The performance of lithium-ion batteries is determined by the architecture and properties of electrodes formed during manufacturing, particularly in the drying process when solvent is removed and the electrode structure is formed. Temperature is one of the most dominant parameters that influences the process, and therefore a comparison of temperature effects on both NMC622-based cathodes (PVDF-based binder) and graphite-based anodes (water-based binder) dried at RT, 60, 80, 100 and 120 °C has been undertaken. X-ray computed tomography showed that NMC622 particles concentrated at the surface of the cathode coating except when dried at 60 °C. However, anodes showed similar graphite distributions at all temperatures. The discharge capacities for the cathodes dried at 60, 80, 100 and 120 °C displayed the following trend: 60 °C < 80 °C < 100 °C < 120 °C as C-rate was increased which was consistent with the trends found in adhesion testing between 60 and 120 °C. Focused-ion beam scanning electrode microscopy and energy-dispersive X-ray spectroscopy suggested that the F-rich binder distribution was largely insensitive to temperature for cathodes. In contrast, conductivity enhancing fine carbon agglomerated on the upper surface of the active NMC particles in the cathode as temperature increased. The cathode dried at RT had the highest adhesion force of 0.015 N mm−1 and the best electrochemical rate performance. Conversely, drying temperature had no significant effect on the electrochemical performance of the anode, which was consistent with only a relatively small change in the adhesion, related to the use of lower adhesion water-based binders

The Astropy Problem

The Astropy Project (http://astropy.org) is, in its own words, "a community effort to develop a single core package for Astronomy in Python and foster interoperability between Python astronomy packages." For five years this project has been managed, written, and operated as a grassroots, self-organized, almost entirely volunteer effort while the software is used by the majority of the astronomical community. Despite this, the project has always been and remains to this day effectively unfunded. Further, contributors receive little or no formal recognition for creating and supporting what is now critical software. This paper explores the problem in detail, outlines possible solutions to correct this, and presents a few suggestions on how to address the sustainability of general purpose astronomical software

Targeting cells with single vectors using multiple-feature Boolean logic

Precisely defining the roles of specific cell types is an intriguing frontier in the study of intact biological systems and has stimulated the rapid development of genetically encoded tools for observation and control. However, targeting these tools with adequate specificity remains challenging: most cell types are best defined by the intersection of two or more features such as active promoter elements, location and connectivity. Here we have combined engineered introns with specific recombinases to achieve expression of genetically encoded tools that is conditional upon multiple cell-type features, using Boolean logical operations all governed by a single versatile vector. We used this approach to target intersectionally specified populations of inhibitory interneurons in mammalian hippocampus and neurons of the ventral tegmental area defined by both genetic and wiring properties. This flexible and modular approach may expand the application of genetically encoded interventional and observational tools for intact-systems biology

Ontogeny and regulation of estrogen receptor isoform expression in rainbow trout (Oncorhynchus mykiss) /by Josh Boyce.

Thesis (Ph. D., Biology)--University of Idaho, November 2009

The ontogeny of nuclear estrogen receptor isoform expression and the effect of 17β-estradiol in embryonic rainbow trout ( Oncorhynchus mykiss)

Ligand bound nuclear estrogen receptor (ER) acts as a transcription factor regulating the expression of estrogen dependent genes. There are four nuclear ER isoforms in rainbow trout ( Oncorhynchus mykiss). The objective of this study was to measure whole body mRNA levels of the two ERα isoforms (α1/α2) and the two ERβ isoforms (β1/β2) in male and female embryos from 50 to 600 degree-days (DD; days post-fertilization × water temperature) and in embryos exposed to vehicle or 17β-estradiol (E2) for 2 h at 230, 240 and 250 DD. All four isoforms were detected at every time point in both sexes. Sexual dimorphism was rarely observed; at 50 DD the level of ERα2 mRNA was significantly greater in males than in females and at 100 DD the level of ERβ1 mRNA was significantly greater in females than in males ( p < 0.05). Expression profiles of the two ERα isoforms were slightly different from one another, whereas the ERβ isoforms exhibited similar expression patterns. The effect of E2 was not different between male and female embryos. The level of ERα1 mRNA increased significantly at 240 DD; a similar but not statistically significant trend was observed at 230 and 250 DD. Despite the critical role of estrogen during sex differentiation in rainbow trout, the receptivity to this hormone as measured by the response in mRNA levels of ER appears to be largely the same between males and females and ERα1 is the only E2 responsive isoform

Variation Among Rainbow Trout (Oncorhynchus mykiss) Estrogen Receptor Isoform 3′ Untranslated Regions and the Effect of 17β-Estradiol on mRNA Stability in Hepatocyte Culture

Adenine and uridine (AU)–rich elements in the 3′ untranslated region (3′UTR) have been implicated in the 17β-estradiol (E2) stabilization of vertebrate estrogen receptor (ER) mRNAs. To date, fishes have the most complex arrangement of nuclear ERs with up to two isoforms of each of the two genes in some species (i.e., four different ERs). The objective of this study was to analyze the sequence variation of 3′UTRs among the four ER isoforms in the rainbow trout and determine to what degree it is responsible for the estrogen-induced increase of ER mRNAs in the liver of this fish. This was done by comparing the 3′UTR DNA sequence length and composition, and by measuring expression of ER isoform 3′UTR luciferase reporter constructs in primary cultures of trout hepatocytes treated with E2. There were large differences both in overall length and in sequence composition among the four ER isoform 3′UTRs. The ERα1 sequence was the longest and the only one of the four that contained multiple copies of the canonical AU-rich elements (AUUUA) as well as the stability sequence (GCUGAU). E2 treatment significantly increased the luciferase activity in cells transiently transfected with the ERα1 reporter construct, relative to cells transfected with reporter vectors containing the other three ER isoform 3′UTRs or the parental vector control. These results support the hypothesis that the E2-induced increase in hepatic ERα1 mRNA in rainbow trout is due in part to sequence variability among ER isoform 3′UTRs. We conclude that posttranscriptional stabilization of ER mRNA by E2 appears to be conserved among vertebrates

Quantitative assessment of machine-learning segmentation of battery electrode materials for active material quantification

Funding Information: This work was made possible by the facilities and support provided by the Research Complex at Harwell. The research was funded by The Faraday Institution [grant numbers: EP/S003053/1, FIRG015, FIRG025]. PRS and DJLB acknowledge the Royal Academy of Engineering for supporting their respective Research Chairs [CiET1718/59 and RCSRF2021/13/53]. Funding Information: This work was made possible by the facilities and support provided by the Research Complex at Harwell . The research was funded by The Faraday Institution [grant numbers: EP/S003053/1 , FIRG015 , FIRG025 ]. PRS and DJLB acknowledge the Royal Academy of Engineering for supporting their respective Research Chairs [ CiET1718/59 and RCSRF2021/13/53 ]. Publisher Copyright: © 2022 The AuthorsPeer reviewedPublisher PD

A Review of Lithium-ion Battery Electrode Drying: Mechanisms and Metrology

Lithium-ion battery manufacturing chain is extremely complex with many controlable parameters especially for the drying process. These processes affect the porous structure and properties of these electrode films, and influence the final cell performance properties. However, there is limited available drying information and the dynamics are poorly understood due to the limitation of the existing metrology. There is an emerging need to develop new methodologies to understand the drying dynamics to achive improved quality control of the electrode coatings. A comprehensive summary of the parameters and variables relevant to the wet electrode film drying process is presented, and its consequences/effects on the finished electrode/final cell properties mapped. The development of the drying mechanism is critically discussed according to existing modelling studies. Then, the existing and potential metrology techniques, either in-situ or ex-situ in the drying process are reviewed. It is the intension to develop new perspectives on the application of advanced techniques to enable a more predictive approach to identify optimum lithium-ion battery manufacturing conditions, with a focus upon the critical drying process