Constructing an artificial solid electrolyte interphase (SEI) on lithium metal electrodes is a promising approach to address the rampant growth of dangerous lithium morphologies (dendritic and dead Li0) and low Coulombic efficiency that plague development of lithium metal batteries, but how Li+transport behavior in the SEI is coupled with mechanical properties remains unknown. We demonstrate here a facile and scalable solution-processed approach to form a Li3N-rich SEI with a phase-pure crystalline structure that minimizes the diffusion energy barrier of Li+across the SEI. Compared with a polycrystalline Li3N SEI obtained from conventional practice, the phase-pure/single crystalline Li3N-rich SEI constitutes an interphase of high mechanical strength and low Li+diffusion barrier. We elucidate the correlation among Li+transference number, diffusion behavior, concentration gradient, and the stability of the lithium metal electrode by integrating phase field simulations with experiments. We demonstrate improved reversibility and charge/discharge cycling behaviors for both symmetric cells and full lithium-metal batteries constructed with this Li3N-rich SEI. These studies may cast new insight into the design and engineering of an ideal artificial SEI for stable and high-performance lithium metal batteries.
This content will become publicly available on May 1, 2025
- Award ID(s):
- 2045262
- NSF-PAR ID:
- 10510027
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Joule
- Volume:
- 8
- ISSN:
- 2542-4351
- Page Range / eLocation ID:
- 1-17
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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