Nonaqueous redox flow batteries hold the promise of achieving higher energy density because of the broader voltage window than aqueous systems, but their current performance is limited by low redox material concentration, cell efficiency, cycling stability, and current density. We report a new nonaqueous all-organic flow battery based on high concentrations of redox materials, which shows significant, comprehensive improvement in flow battery performance. A mechanistic electron spin resonance study reveals that the choice of supporting electrolytes greatly affects the chemical stability of the charged radical species especially the negative side radical anion, which dominates the cycling stability of these flow cells. This finding not only increases our fundamental understanding of performance degradation in flow batteries using radical-based redox species, but also offers insights toward rational electrolyte optimization for improving the cycling stability of these flow batteries.
The increased interest in using monoclonal antibodies (mAbs) as a platform for biopharmaceuticals has led to the need for new analytical techniques that can precisely assess physicochemical properties of these large and very complex drugs for the purpose of correctly identifying quality attributes (QA). One QA, higher order structure (HOS), is unique to biopharmaceuticals and essential for establishing consistency in biopharmaceutical manufacturing, detecting process-related variations from manufacturing changes and establishing comparability between biologic products. To address this measurement challenge, two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR) methods were introduced that allow for the precise atomic-level comparison of the HOS between two proteins, including mAbs. Here, an inter-laboratory comparison involving 26 industrial, government and academic laboratories worldwide was performed as a benchmark using the NISTmAb, from the National Institute of Standards and Technology (NIST), to facilitate the translation of the 2D-NMR method into routine use for biopharmaceutical product development. Two-dimensional 1H,15N and 1H,13C NMR spectra were acquired with harmonized experimental protocols on the unlabeled Fab domain and a uniformly enriched-15N, 20%-13C-enriched system suitability sample derived from the NISTmAb. Chemometric analyses from over 400 spectral maps acquired on 39 different NMR spectrometers ranging from 500 MHz to 900 MHz demonstrate spectral fingerprints that are fit-for-purpose for the assessment of HOS. The 2D-NMR method is shown to provide the measurement reliability needed to move the technique from an emerging technology to a harmonized, routine measurement that can be generally applied with great confidence to high precision assessments of the HOS of mAb-based biotherapeutics.
Nonaqueous redox flowb atteries hold the promise of achieving higher energy density because of the broader voltage window than aqueous systems,b ut their current performance is limited by lowr edox material concentration, cell efficiency,cycling stability,and current density.W er eport an ew nonaqueous all-organic flow battery based on high concentrations of redox materials,w hich shows significant, comprehensive improvement in flow battery performance.A mechanistic electron spin resonance study reveals that the choice of supporting electrolytes greatly affects the chemical stability of the charged radical species especially the negative side radical anion, which dominates the cycling stability of these flowc ells.T his finding not only increases our fundamental understanding of performance degradation in flow batteries using radical-based redox species,b ut also offers insights towardrational electrolyte optimization for improving the cycling stability of these flowb atteries.The redox flow battery (RFB) has recently attracted agreat deal of interest as as afe and cost-effective energy storage technology for power grid applications.[1] By storing dissolved electroactive materials in external tanks,t he RFB decouples the energy and the power thus gaining tremendous design flexibility to meet different energy-to-power ratio (E/P) applications.C onventional aqueous RFBs are generally lowenergy systems limited mainly by the narrow electrochemical stability window of water.[2] Although the energy density is generally not considered as ac ritical performance criterion for stationary applications,the low energy density of aqueous RFBs has nevertheless disqualified them from other energy storage markets.T herefore,r ecent efforts have shifted to developing nonaqueous RFBs (NRFBs) because of their potential high energy density due to the wider electrochemical window of nonaqueous electrolytes.[3] Current NRFB research is primarily focused on seeking viable redox materials for various flow chemistries,f or example,m etal coordination compounds [4] and organic redox molecules.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.