Lithium-Ion Electrolytes Containing Phosphorous-Based, Flame-Retardant Additives

Future NASA missions aimed at exploring Mars, the Moon, and the outer planets require rechargeable batteries that can operate over a wide temperature range (-60 to +60 C) to satisfy the requirements of various applications. In addition, many of these applications will require improved safety, due to their use by humans. Currently, the state-of-the-art lithium-ion (Li-ion) system has been demonstrated to operate over a wide range of temperatures (-40 to +40 C); however, abuse conditions can often lead to cell rupture and fire. The nature of the electrolyte can greatly affect the propensity of the cell/battery to catch fire, given the flammability of the organic solvents used within. Li-ion electrolytes have been developed that contain a flame-retardant additive in conjunction with fluorinated co-solvents to provide a safe system with a wide operating temperature range. Previous work incorporated fluorinated esters into multi-component electrolyte formulations, which were demonstrated to cover a temperature range from 60 to +60 C. This work was described in Fluoroester Co-Solvents for Low-Temperature Li+ Cells (NPO-44626), NASA Tech Briefs, Vol. 33, No. 9 (September 2009), p. 37; and Optimized Li-Ion Electrolytes Con tain ing Fluorinated Ester Co-Solvents (NPO-45824), NASA Tech Briefs, Vol. 34, No. 3 (March 2010), p. 48. Other previous work improved the safety characteristics of the electrolytes by adding flame-retardant additives such as triphenyl phosphate (TPhPh), tri-butyl phosphate (TBuPh), triethyl phosphate (TEtPh), and bis(2,2,2-trifluoroethyl) methyl phosphonate (TFMPo). The current work involves further investigation of other types of flame-retardant additives, including tris(2,2,2-trifluoroethyl) phosphate, tris(2,2,2-trifluoroethyl) phosphite, triphenylphosphite, diethyl ethylphosphonate, and diethyl phenylphosphonate added to an electrolyte composition intended for wide operating temperatures. In general, many of the formulations investigated in this study displayed good performance over a wide temperature range, good cycle life characteristics, and are expected to have improved safety characteristics, such as low flammability. Of the electrolytes studied, 1.0 M LiPF6 in EC+EMC+DEP (20:75:5 v/v %) and 1.0 M LiPF6 in EC+EMC+DPP (20:75:5 v/v %) displayed the best operation at low temperatures, whereas the electrolyte containing triphenylphosphite displayed the best cycle life performance compared to the baseline solution. It is anticipated that further improvements can be made to the life characteristics with the incorporation of a SET promoters (such as VC, vinylene carbonate), which will likely inhibit the decomposition of the flame-retardant additives

Lithium-Ion Electrolytes Containing Flame Retardant Additives for Increased Safety Characteristics

The invention discloses various embodiments of Li-ion electrolytes containing flame retardant additives that have delivered good performance over a wide temperature range, good cycle life characteristics, and improved safety characteristics, namely, reduced flammability. In one embodiment of the invention there is provided an electrolyte for use in a lithium-ion electrochemical cell, the electrolyte comprising a mixture of an ethylene carbonate (EC), an ethyl methyl carbonate (EMC), a fluorinated co-solvent, a flame retardant additive, and a lithium salt. In another embodiment of the invention there is provided an electrolyte for use in a lithium-ion electrochemical cell, the electrolyte comprising a mixture of an ethylene carbonate (EC), an ethyl methyl carbonate (EMC), a flame retardant additive, a solid electrolyte interface (SEI) film forming agent, and a lithium salt

Integrated Proteomics-Based Physical and Functional Mapping of AXL Kinase Signaling Pathways and Inhibitors Define Its Role in Cell MigrationSystems Analysis of AXL Signaling in Lung Cancers

To better understand the signaling complexity of AXL, a member of the tumor-associated macrophage (TAM) receptor tyrosine kinase family, we created a physical and functional map of AXL signaling interactions, phosphorylation events, and target-engagement of three AXL tyrosine kinase inhibitors (TKI). We assessed AXL protein complexes using proximity-dependent biotinylation (BioID), effects of AXL TKI on global phosphoproteins using mass spectrometry, and target engagement of AXL TKI using activity-based protein profiling. BioID identifies AXL-interacting proteins that are mostly involved in cell adhesion/migration. Global phosphoproteomics show that AXL inhibition decreases phosphorylation of peptides involved in phosphatidylinositol-mediated signaling and cell adhesion/migration. Comparison of three AXL inhibitors reveals that TKI RXDX-106 inhibits pAXL, pAKT, and migration/invasion of these cells without reducing their viability, while bemcentinib exerts AXL-independent phenotypic effects on viability. Proteomic characterization of these TKIs demonstrates that they inhibit diverse targets in addition to AXL, with bemcentinib having the most off-targets. AXL and EGFR TKI cotreatment did not reverse resistance in cell line models of erlotinib resistance. However, a unique vulnerability was identified in one resistant clone, wherein combination of bemcentinib and erlotinib inhibited cell viability and signaling. We also show that AXL is overexpressed in approximately 30% to 40% of nonsmall but rarely in small cell lung cancer. Cell lines have a wide range of AXL expression, with basal activation detected rarely. Our study defines mechanisms of action of AXL in lung cancers which can be used to establish assays to measure drug targetable active AXL complexes in patient tissues and inform the strategy for targeting it's signaling as an anticancer therapy

SARS-CoV-2 vaccination modelling for safe surgery to save lives: Data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population