Enabling 420 Wh kg −1 Stable Lithium‐Metal Pouch Cells by Lanthanum Doping

Lithium (Li) metal, a promising anode for high-energy-density rechargeable batteries, typically grows along the low-surface energy (110) plane in the plating process, resulting in uncontrollable dendrite growth and unstable interface. Herein, an unexpected Li growth behavior by lanthanum (La) doping is reported: the preferred orientation turns to (200) from (110) plane, enabling 2D nuclei rather than the usual 1D nuclei upon Li deposition and thus forming a dense and dendrite-free morphology even at an ultrahigh areal capacity of 10 mAh cm-2 . Noticeably, La doping further decreases the reactivity of Li metal toward electrolytes, thereby establishing a stable interface. The dendrite-free, stable Li anode enables a high average Coulombic efficiency of 99.30% at 8 mAh cm-2 for asymmetric Li||LaF3 -Cu cells. A 3.1 Ah LaF3 -Li||LiNi0.8 Co0.1 Mn0.1 O2 pouch cell at a high energy density (425.73 Wh kg-1 ) with impressive cycling stability (0.0989% decay per cycle) under lean electrolyte (1.76 g Ah-1 ) and high cathode loading (5.77 mAh cm-2 ) using this doped Li anode is further demonstrated.