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Cathodes of lithium-ion batteries (LIBs) significantly impact the environmental footprint, cost, and energy performance of the battery-pack. Hence, sustainable production of Li-ion battery cathodes is critically required for ensuring cost-effectiveness, environmental benignity, consumer friendliness, and social justice. Battery chemistry largely determines individual cell performance as well as the battery pack cost and life cycle greenhouse gas emission. Continuous manufacturing platforms improve production efficiency in terms of product yield, quality and cost. Spent-battery recycling ensures the circular economy of critical elements that are required for cathode production. Innovations in fast-charging LIBs are particularly promising for sustainable e-mobility with a reduced carbon footprint. This article provides an overview of these research directions, emphasizing strategies for low-cobalt cathode development, recycling processes, continuous production and improvement in fast-charging capability. 

The intermittent nature of the renewable energy sources drifts research interest towards various electrochemical energy storage devices, such as the lithium ion battery, which offers consistent power supply. The manufacturing cost and electrochemical performance of a battery pack largely depends on the quality of the cathode material, which further depends on the production method and its parameters. However, the traditional stirred tank-based co-precipitation manufacturing process for precursors of lithium nickel manganese cobalt oxide (NCM111) cathode suffers from inhomogeneity in the reaction environment, which leads to non-uniform morphology and particle size distribution (PSD). In this work, slug-flow-based manufacturing platform, which offers a homogeneous reaction environment, is used for the continuous production of NCM111 oxalate precursors. One of the novel features of this work is the comparative study between the quality of batch and slug-flow-derived products. The slug-flow-derived product is found to be better in terms of having bigger particle size, narrower PSD and higher tap density. The study on the single and dual-element precipitation in similar conditions to understand the co-precipitation behavior in the slug-flow manufacturing platform is also a unique feature of this work. Furthermore, the effect of NH4OH concentration and residence time (RT) on the electrochemical performance of cathode were also studied and it is found that the cathode precursors synthesized at a NH4OH concentration of 0.08 M and a RT of 2 minutes followed by lithiation shows a better electrochemical performance of 128 mAh g−1 at 0.1 C with cycling stability of more than 80% both at 0.5 C and 1 C. 

Hypoxia is a common feature of most solid tumors, one that favors tumor progression and limits treatment effectiveness. Targeting hypoxia has long been a goal in cancer therapy, by identifying factors that reverse or ameliorate the effects of hypoxia on cancer cells. We, and others, have shown that β-caryophyllene (BCP) exhibits anti-proliferative properties in cancer cells. We have further shown that non-cytotoxic concentrations of BCP affect cholesterol and lipid biosynthesis in hypoxic hBrC cells at both transcriptional and translational levels. This led us to hypothesize that BCP may reverse the hypoxic phenotype in hBrC cells. To test this, we determined the effect of BCP on hypoxic sensitive pathways, including oxygen consumption, glycolysis, oxidative stress, cholesterol and fatty acid biosynthesis, and ERK activation. While each of these studies revealed new information on the regulation by hypoxia and BCP, only the lipidomic studies showed reversal of hypoxic-dependent effects by BCP. These later studies showed that hypoxia-treated samples lowered monounsaturated fatty acid levels, shifting the saturation ratios of the fatty acid pools. This signature was ameliorated by sub-lethal concentrations of BCP, possibly through an effect on the C:16 fatty acid saturation ratios. This is consistent with BCP-induced upregulation of the stearoyl-CoA desaturase (SCD) gene, observed previously. This suggests that BCP may interfere with the lipid signature modulated by hypoxia which could have consequences for membrane biosynthesis or composition, both of which are important for cell replication. 

Cost-effective production of low cobalt Li-ion battery (LIB) cathode materials is of great importance to the electric vehicle (EV) industry to achieve a zero-carbon economy. Among the various low cobalt cathodes, Ni-rich lithium nickel cobalt manganese oxide (NCM/NMC)-based layered materials are commonly used in EVs and are attracting more attention of the scientific community due to their high specific capacity and energy density. Various synthesis routes are already established to produce Ni-rich NCM cathodes with uniform particle size distribution and high tap density. Continuous production of highly pure Ni-rich cathode materials with uniformity in inter/intra-particle compositional distribution is critically required. On the other hand, cation mixing, particle cracking, and parasitic side reactions at higher voltage and temperature are some of the primary challenges of working with Ni-rich NCM cathodes. During the past five years, several advanced modification strategies such as coating, doping, core–shell, gradient structure and single crystal growth have been explored to improve the NCM cathode performance in terms of specific capacity, rate-capability and cycling stability. The scientific advancements in the field of Ni-rich NCM cathodes in terms of manufacturing processes, material challenges, modification techniques, and also the future research direction of LIB research are critically reviewed in this article. 

This paper reports on research that is part of a broader National Science Foundation (NSF)-funded, Innovations in Graduate Education (IGE) project. The project aims to enhance the research culture and broaden the participation in research of underrepresented groups within graduate engineering programs at a mid-sized historically black college or university. The project includes three initiatives that seek to assist in the development of a “research engineer identity” among the graduate students pursuing research-based degrees in the college. One of the three initiatives of the project, and focus of this paper, involves the development of a survey-based Research Engineer Identity Scale (REIS). A two stage sequential mixed-method research design is being used to develop the scale. This paper focuses on the first stage in the design which involved conducting focus groups with research engineers to gain insight into the content, character, and complications associated with internalizing a Research Engineer Identity (REI) in general and among people from underrepresented groups in particular. We report on four semi-structured focus groups that each lasted approximately 90 minutes in Fall 2019. Each focus group included about 6 to 9 faculty members, industry professionals, or graduate students who actively engaged in engineering research in the Southeastern United States. Focus group participants represented various academic disciplines within engineering as well as a range of demographic characteristics such as sex, race, ethnicity, and citizenship status. The focus group conversations were transcribed and transcriptions were entered into NVivo for coding and analysis. Inter-rater reliability procedures were used to ensure consistency of coding. This paper reports on the themes that emerged within the focus group discussions regarding what it means to “be a research engineer.” The findings describe similarities and differences across demographic characteristics in regard to the content, character, and complications associated with efforts to develop a Research Engineer Identity. The paper concludes by briefly describing the process that will be used to transform the emergent themes into pool of items to be included in a web-based questionnaire designed to measure Research Engineer Identity.