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Abstract A dual‐layer interphase that consists of an in‐situ‐formed lithium carboxylate organic layer and a thin BF3‐doped monolayer Ti3C2MXene on Li metal is reported. The honeycomb‐structured organic layer increases the wetting of electrolyte, leading to a thin solid electrolyte interface (SEI). While the BF3‐doped monolayer MXene provides abundant active sites for lithium homogeneous nucleation and growth, resulting in about 50% reduced thickness of inorganic‐rich components among the SEI layer. A low overpotential of less than 30 mV over 1000 h cycling in symmetric cells is received. The functional BF3 groups, along with the excellent electronic conductivity and smooth surface of the MXene, greatly reduce the lithium plating/stripping energy barrier, enabling a dendrite‐free lithium‐metal anode. The battery with this dual‐layer coated lithium metal as the anode displays greatly improved electrochemical performance. A high capacity‐retention of 175.4 mAh g−1at 1.0 C is achieved after 350 cycles. In a pouch cell with a capacity of 475 mAh, the battery still exhibits a high discharge capacity of 165.6 mAh g−1with a capacity retention of 90.2% after 200 cycles. In contrast to the fast capacity decay of pure Li metal, the battery using NCA as the cathode also displays excellent capacity retention in both coin and pouch cells. The dual‐layer modified surface provides an effective approach in stabilizing the Li‐metal anode.
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This content will become publicly available on June 29, 2026
Revealing the Micro‐Size Effect in Alloy Anodes for High‐Capacity and Long‐Cycling Sulfide‐Based Solid‐State Batteries
Abstract Solid‐state batteries (SSBs) are competitive contenders for energy storage due to their inherent safety and high energy. However, the lack of an appropriate anode has hindered their development. Graphite and lithium metal are widely used anode materials, but graphite suffers from a low capacity, whereas lithium metal presents severe dendrite and reactivity challenges. Herein, the promising performance of micro‐sized alloys is demonstrated as high‐capacity and long‐cycling anodes for SSBs. Using antimony as a model anode, its full theoretical capacity (660 mAh g−1), high‐rate capability (3 A g−1), and long cycling life (1000–2000 cycles) is achieved at room temperature. Comparative studies further reveal an overlooked “micro‐size effect”, where micro‐sized alloys establish more efficient electron/ion conduction pathways, significantly exceeding their nano‐sized counterparts. This micro‐size effect challenges the conventional belief that nano‐sized alloys always outperform micro‐sized ones. Based on this discovery, similarly high performance of other micro‐alloys (lead and bismuth) in SSBs is further demonstrated. Given the additional benefits of easy synthesis, low cost, high tap density, and high stability, micro‐sized alloys hold great promise as excellent anode candidates for SSBs.
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- Award ID(s):
- 2434152
- PAR ID:
- 10656562
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Small
- Volume:
- 21
- Issue:
- 34
- ISSN:
- 1613-6810
- Page Range / eLocation ID:
- 2504481
- Subject(s) / Keyword(s):
- high performance, micro-size effect, micro-sized alloys, Solid-state batteries, sulfide electrolytes
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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