Advanced design of hybrid interfaces for high-performance all-solid-state lithium metal batteries

Li 7 P 3 S 11 -based all-solid-state lithium metal batteries (ASSLMBs) have received a lot of attention because of their potential for high energy density . However, the poor interfacial stability between Li 7 P 3 S 11 electrolyte and lithium metal anode hinders its application in ASSLMBs. Here, the Li-SnO 2 composite anode (LSO) was designed by treating the lithium metal with SnO 2 to produce an interface composed of Li 22 Sn 5 and Li 2 O phases. The rapid lithium ion diffusion coefficient of Li 22 Sn 5 alloy accelerates the migration of lithium ions at the interface, while the favorable lithiophilicity of Li 2 O induces the uniform deposition of lithium ions, which hinders the growth of lithium dendrites . Therefore, the symmetrical battery using an LSO anode showed a high critical current density (CCD) of 2.5 mA cm −2 at room temperature and a stable cycle of 350 h at room temperature at 0.2 mA cm −2 (0.2 mAh cm −2 ). In addition, the improved all-solid-state lithium battery also showed an ultra-stable cycle, and the NCM622/LPS/10LSO battery still maintained 78.6 % of its original capacity after 250 cycles at 0.5C. The surface treatment method of the LSO composite anode enables it to produce ASSLMB with excellent electrochemical performance .