Interfacial Energy Engineering via Fluorine Doping Suppresses Lithium Self-Permeation in Li<sub>3</sub>N Solid Electrolytes.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41961291.
- Also identified by DOI 10.1021/acs.nanolett.6c00381.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Non-electrochemical lithium (Li) permeation into solid-state electrolytes (SSEs) poses a latent yet critical failure mode for all-solid-state lithium metal batteries (ASSLMBs). This work reveals severe Li self-permeation in the Li<sub>3</sub>N SSE under pressure and heat, forming mixed conductive regions that undermine interfacial stability. To address this problem, we developed an anion-tuning strategy by doping Li<sub>3</sub>N with LiF to obtain Li<sub>2.9</sub>N<sub>0.95</sub>F<sub>0.05</sub>. Fluorine substitution elevates the interfacial energy between Li and SSE, effectively suppressing spontaneous Li permeation. Li<sub>2.9</sub>N<sub>0.95</sub>F<sub>0.05</sub> exhibits high ionic conductivity (5.8 × 10<sup>-4</sup> S cm<sup>-1</sup>) and low activation energy (0.326 eV). Consequently, Li-symmetric cells achieve stable cycling for >1000 h at 0.2 mA cm<sup>-2</sup>, and the ASSLMB employing Li<sub>2.9</sub>N<sub>0.95</sub>F<sub>0.05</sub> as SSE interlayers and LiCoO<sub>2</sub> cathodes retain 80% capacity after 120 cycles at 0.5 C, demonstrating engineering viability. This study provides an effective pathway to stabilize Li metal interfaces and advance the performance of ASSLMBs.