No abstract

All-ceramic cathode-electrolyte with a low interfacial resistance can be realized by thermally soldering LiCoO 2 and Li 7 La 3 Zr 2 O 12 (LLZO) together with Li 2.3Àx C 0.7+x B 0.3Àx O 3 solid electrolyte interphase through the reaction between the Li 2.3 C 0.7 B 0.3 O 3 solder and the Li 2 CO 3 layers that can be spontaneously coated on both LLZO and LiCoO 2. The all-solid-state Li/LLZO/LiCoO 2 battery with such an all-ceramic cathode/electrolyte exhibits high cycling stability and high rate performance.

Garnet-type solid-state electrolytes (SSEs) are considered to be a good choice for solid-state batteries, yet the interfacial issues with metallic Li limit their applications. Herein, we propose an ultrasimple and effective strategy to enhance the interfacial connection between garnet SSEs and Li metal just by drawing a graphite-based soft interface with a pencil. Both experimental analysis and theoretical calculations confirm that the reaction between the graphite-based interfacial layer and metallic lithium forms a lithiated connection interface with good lithium-ionic and electronic conductivity. Compared to the reported interfacial materials, the graphite provides a soft interface with better ductility and compressibility. With improvement by this soft interface, the impedance of symmetric Li cells significantly decreases and the cell cycle is stable for over 1000 h. Moreover, a solid-state battery with Li-metal anode, ternary NCM523 cathode, and treated-garnet SSEs is fabricated and displays excellent rate capability and long cycling performance.