The Buffer Layer for Anode-Free Architecture in Solid-State Batteries

Li-metal solid-state batteries are the holy grail for the next-generation rechargeable battery technology due to their improved safety and energy densities. The anode-free architecture for solid-state batteries (AFSSB) is an emerging structure to reduce the cost of handling Li-metal foil and further increase the volumetric and gravimetric energy densities. Adding a buffer layer (BL) between the current collector (CC) and the SE seems a promising strategy to tackle the remaining issues in AFSSB (such as dendrites growth and low Coulombic efficiency).<br/>However, except for several preliminary trials reported at the laboratory scale, there is no research yet on the systematic investigations of the AFSSB architecture with a BL, let alone proposing an optimized design/prototype for this new structure. An optimized design should be mainly focused on the innovation at the anode side, including the selection of BL material (usually contains Li-alloyable metals and matrix material) and the pairing CC and SE material, the control of BL microstructure (porosity, particle size, and weight ratio), and the treatment of BL interfacial properties (surface adhesion, charge-transfer, etc.) with the CC and the SE. We apply our data-simulation-experiment approach to find out the optimized design for the AFSSB with BL. The house-developed approach brings together multi-scale simulations, data processing, mechanical design, and experimental efforts.