A mortise-tenon-like ionic/electronic conductive interface facilitates long-cycle solid-state lithium metal batteries

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024-11, Vol.12 (45), p.3157-3158
• Main Authors: Zheng, Guoxiang, Jin, Yifan, Sedla ík, Michal, Vargun, Elif, Zhang, Yifan, He, Ying, Saha, Petr, Cheng, Qilin
• Format: Article
• Language: English
• Subjects: Critical current density; Cycles; Electrolytes; Electrolytic cells; Energy storage; Garnets; Impedance; Ion currents; Lithium; Lithium batteries; Lithium chloride; Molten salt electrolytes; Solid electrolytes; Solid state; Specific capacity; Zinc base alloys
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d4ta05312e

Solid-state lithium metal batteries (SSLMBs) with high energy density and superior safety have been recognized as next-generation energy storage systems and have attracted a lot of attention. Garnet-type oxide solid-state electrolytes, especially Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO), with high ionic conductivity, low activation energy and superior stability with Li, are among the most promising solid-state electrolyte materials. However, high interfacial resistance, uneven lithium deposition and lithium dendrite growth between Li/LLZTO interfaces have hindered the industrialization of SSLMBs. In this work, a novel mortise-tenon-like hybrid ionic/electronic conductive interface (Li/LZFC@LLZTO) is constructed, which is composed of LiF, LiCl, and a Li-Zn alloy through an in situ transformation reaction. As expected, the interfacial impedance of Li|LZFC@LLZTO|Li is significantly reduced from 128 Ω cm 2 to 2.7 Ω cm 2 , the critical current density increases from 0.3 mA cm −2 to 2.1 mA cm −2 , and a prominent cycling performance of 6600 h at 0.2 mA cm −2 or 900 h at 0.4 mA cm −2 is achieved. Consequently, both the Li|LZFC@LLZTO|LiFePO 4 and Li|LZFC@LLZTO|LiNi 0.8 Co 0.1 Mn 0.1 O 2 full cells exhibit excellent rate performance. Furthermore, Li|LZFC@LLZTO|LiFePO 4 can maintain a high discharge specific capacity close to 140 mA h g −1 at 0.2C after 150 cycles of stable cycling. This work lays the foundation for developing garnet-based SSLMBs with high critical current density, low interfacial impedance and long-term cycling performance. Solid-state lithium metal batteries (SSLMBs) with high energy density and superior safety have been recognized as next-generation energy storage systems and have attracted a lot of attention.