Interface-induced fast Li+ transport in mixed ionic–electronic conductors

He, Chenche; Zhang, Zhuoxun; Li, Tao

doi:10.1039/d6cc00741d

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Interface-induced fast Li+ transport in mixed ionic–electronic conductors

He, Chenche·Zhang, Zhuoxun·Li, Tao

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Abstract

Interfacial instability between lithium metal and solid-state electrolytes limits the performance of all-solid-state lithium metal batteries (ASSLBs), leading to parasitic reactions, non-uniform Li+ flux, and dendrite growth. Here, we develop a composite interlayer composed of the anti-perovskite Li2OHCl0.75Br0.25 (AP) and carbon nanotubes (CNTs) to enhance both interfacial stability and ionic transport. The AP–CNT interlayer exhibits enhanced Li+ conductivity arising from interfacial electron transfer from AP to CNTs, which generates a built-in electric field that facilitates Li+ migration. Lithium symmetric cells incorporating this interlayer achieve a high critical current density of 2.4 mA cm−2 at 55 °C. This design integrates chemical robustness with coupled ion–electron transport, offering a generalizable strategy for safe, dendrite-free, and high-performance ASSLBs.

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He, Chenche, Zhang, Zhuoxun, Li, Tao. 2026-06-09. Interface-induced fast Li+ transport in mixed ionic–electronic conductors. https://doi.org/10.1039/d6cc00741d

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