A Tailored Interface Design for Anode-free Solid-State Batteries.

Anode-free solid-state batteries (AFSSBs) are considered to be one of the most promising high-safety and high-energy storage systems. However, low Coulombic efficiency stemming from severe deterioration on solid electrolyte/current collector (Cu foil) interface and undesirable Li dendrite growth impede their practical application, especially when rigid garnet electrolyte is used. In this study, we introduced an interfacial engineering strategy between garnet electrolyte and Cu foil for stable and highly-efficient AFSSBs. By utilizing the high Li ion conductivity of LiC 6 layer, interfacial self-adaption ability arising from ductile lithiated poly-acrylic acid (LiPAA) polymer layer and regulated Li deposition via Li-Ag alloying reaction, the garnet-based AFSSB delivers a stable long-term operation. Additionally, when combined with a commercial LiCoO 2 cathode (3.1 mAh cm -2 ), the cell also exhibits an outstanding capacity retention due to the tailored interface design. Our strategies for novel AFSSBs architecture thus offer an alternative route to design next-generation batteries with high safety and high density. This article is protected by copyright. All rights reserved.