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Abstract The energetic chemical reaction between Zn(NO3)2and Li is used to create a solid‐state interface between Li metal and Li6.4La3Zr1.4Ta0.6O12(LLZTO) electrolyte. This interlayer, composed of Zn, ZnLixalloy, Li3N, Li2O, and other species, possesses strong affinities with both Li metal and LLZTO and affords highly efficient conductive pathways for Li+transport through the interface. The unique structure and properties of the interlayer lead to Li metal anodes with longer cycle life, higher efficiency, and better safety compared to the current best Li metal electrodes operating in liquid electrolytes while retaining comparable capacity, rate, and overpotential. All‐solid‐state Li||Li cells can operate at very demanding current–capacity conditions of 4 mA cm−2–8 mAh cm−2. Thousands of hours of continuous cycling are achieved at Coulombic efficiency >99.5 % without dendrite formation or side reactions with the electrolyte.
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Gaseous Nitrogen Oxides Catholyte for Rechargeable Redox Flow Batteries
Abstract There is a strong interest in finding highly soluble redox compounds to improve the energy density of redox flow batteries (RFBs). However, the performance of electrolytes is often negatively influenced by high solute concentration. Herein, we designed a high‐potential (0.5 V vs. Ag/Ag+) catholyte for RFBs, where the charged and discharged species are both gaseous nitrogen oxides (NOx). These species can be liberated from the liquid electrolyte and stored in a separate gas container, allowing scale‐up of storage capacity without increasing the concentration and volume of the electrolyte. The oxidation of NO in the presence of NO3−affords N2O3, and the reduction of N2O3regenerates NO and NO3−, together affording the electrochemical reaction: NO3−+3 NO⇌2 N2O3+e−with a low mass/charge ratio of 152 grams per mole of stored electron. A proof‐of‐concept NOxsymmetric H‐cell shows 200 stable cycles over 400 hours with >97 % Coulombic efficiency and negligible capacity decay.
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- Award ID(s):
- 2124604
- PAR ID:
- 10397462
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 62
- Issue:
- 9
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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