Topological Li‐SbF 3 @Cu Alloying Anode for High‐Energy‐Density Li Metal Batteries

Abstract The ultrathin Lithium (Li) alloying anode (≤ 50 µm) plays a key role in advancing rechargeable Li metal batteries into practical use, especially because of the insurmountable difficulties in developing pure Li anode. Herein, a thickness‐controllable (≈5.5–30 µm) and topological Li‐SbF 3 @Cu anode with the embedded dual Li‐based (Li 3 Sb and Li‐Cu) alloys and outmost LiF‐rich layer is prepared for high‐energy‐density Li metal batteries under high Li utilization. Upon cycling, the surface LiF‐rich layer together with inner lithiophilic Li 3 Sb sites and ferroconcrete‐like Li‐Cu skeletons, synergistically regulates the Li deposition/dissolution behaviors and Li/electrolyte interface evolution. The assembled Li‐SbF 3 @Cu symmetric cell can cycle stably over 1200 h at 1 mA cm −2 /1 mAh cm −2 , and realize an ultrahigh discharge/charge depth of 53.6% at 2 mA cm −2 /3 mAh cm −2 . Moreover, a full cell with a high‐Li‐capacity LiCoO 2 cathode (3.8 mAh cm −2 ) delivers an energy density of 394.5 Wh kg −1 with impressive cycling reversibility at a low negative/positive electrode capacity (N/P) ratio of 1.5. All the findings provide a rewarding avenue toward the industrial application of high‐Li‐utilization alloying anodes for practical high‐energy‐density Li metal batteries.