Interphasial Li+ flux engineering for uniform lithium deposition toward high-areal-capacity and anode-less lithium metal batteries
Lithium metal anodes face critical barriers to practical application due to dendritic growth and interfacial instability, which cause short cycle life and safety hazards. This work introduces a highly stable and ultrahigh-rate lithium metal anode using a lithiophilic Sm2S3-modified carbonaceous host. The in situ formation of a Li2S-reinforced interphase layer enables highly reversible lithium plating/stripping and uniform deposition. The modified anode achieves an ultrahigh rate capability of 20 mA cm−2 and ultralong cycling stability of 7440 cycles with dendrite-free morphology. In a 4.5 V anode-less Li||LiCoO2 cell with an areal capacity of ~1.93 mA h cm−2, the system sustains over 1100 cycles with 87.2% capacity retention under harsh conditions: an ultralow negative-to-positive capacity ratio (N/P) of ~0.26 and lean electrolyte of ~5 g Ah−1. Furthermore, an anode-less pouch cell with an ultrahigh areal capacity of ~6.01 mA h cm−2 delivers superior cycling performance even at an ultra-low N/P ratio of ~0.71 and ultra-lean electrolyte of ~1 g Ah−1, achieving a high energy density of 505 Wh kg−1. This work provides a scalable and effective strategy for advancing reliable, practical lithium metal batteries.