Graphite-Based Lithium-Free 3D Hybrid Anodes for High Energy Density All-Solid-State Batteries

All-solid-state lithium batteries often suffer from dendrite-driven shorting. Here, a lithium-free 3D anode design is reported to help address this challenge. Upon controlling the graphite anode and lithium metal oxide cathode capacity ratio, lithium metal deposition is intentionally induced in the pores formed by the 3D framework of the graphite and lithium thiophosphate-based solid electrolyte. By facilitating lithium deposition away from the interface between the anode composite and the solid-state electrolyte layer, this designed electrode can significantly mitigate the short-circuit problem in the battery. The 3D anode design demonstrates a 3-fold increase in critical current density over a planar lithium metal electrode when evaluated in a symmetric cell. Moreover, the lithium-free all-solid-state battery with a 3D anode and a LiNi0.85Co0.10Al0.05O2 (NCA) cathode also exhibits highly improved cycle life and Coulombic efficiency compared to the baseline cells. This electrode design provides a promising approach toward a high energy density, long life, and low-cost technology.