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Anode-free lithium-sulfur batteries feature a cell design with a fully-lithiated cathode and a bare current collector as an anode to control the total amount of lithium in the cell. The lithium stripping and deposition is a key factor in designing an anode-free full cell to realize a practical cell configuration. To realize effective anode protection and achieve a good performance of the anode-free full cell, the manipulation of the electrolyte chemistry toward the modification of the solid-electrolyte interphase on the anode is considered a feasible approach. In this study, the use of neodymium triflate, Nd(OTf)3, as a dual-function electrolyte additive is demonstrated to promote homogeneous catalysis on the cathode conversion reactions and the anode stabilization. Nd(OTf)3 not only facilitates the conversion reaction by promoting the polysulfide adsorption, but also effectively protects the lithium-metal anode and stabilizes the lithium stripping and deposition during cycling. With this electrolyte modification, both Li ǁ Li2S half cells and Ni ǁ Li2S anode-free full cells support a high areal capacity of 5.5 – 7.0 mA h cm-2 and maintain a high Coulombic efficiency of 94 – 95% during cycling.
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Microstructural Changes in Ni-YSZ Electrodes Operated in Fuel Cell and Electrolysis Modes: Effect of Gas Diffusion Limitations
Ni-YSZ electrode support symmetric cells were operated at 0, 0.75, 1.00, and 1.50 A/cm 2 for 1000 h in 50% H 2 -50% H 2 O at 800 ˚C. Electrochemical fracture at the anode-electrolyte interface is observed to occur under high anodic overpotential. Ni migration is observed and quantified over time at the anode of the polarized cells; however, the cathode shows no migration compared to control. Gas diffusion calculations show that steam is significantly enriched and depleted at the anode and cathode respectively, leading to the formation or suppression of volatile Ni(OH) x species, which have been hypothesized as a transport pathway for Ni. However; gas flux calculations show that chemical evaporation alone is unlikely to be fast enough to induce the Ni loss observed.
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- Award ID(s):
- 1912530
- PAR ID:
- 10422982
- Date Published:
- Journal Name:
- ECS Transactions
- Volume:
- 111
- Issue:
- 6
- ISSN:
- 1938-5862
- Page Range / eLocation ID:
- 1907 to 1916
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1149/11106.1907ecst
