Self-supported 3D current collector modified with in-situ formed lithiophilic [Cu(NH3)2]Cl for high-performance Li-metal batteries

Abstract

Li-metal batteries (LMBs) are regarded as some of the most promising energy storage systems owing to their superior theoretical specific capacity and lowest electrochemical potential. However, the application of LMBs has been severely hindered by the uncontrollable dendrite growth and volume expansion of metal anodes during Li plating. Herein, we construct a three-dimensional (3D) porous CuZn current collector decorated with a lithiophilic [Cu(NH3)2]Cl compound (3D 1H3N), in which [Cu(NH3)2]Cl offers nucleation sites and guides fast Li+ deposition in the pores and tunnels. The 3D framework accommodates volume expansion and disperses deposition current. Together, these two functions contribute to low-barrier and dendrite-free Li plating/stripping with enhanced Coulombic efficiency (CE) and excellent stability. The half-cell utilizing the as-fabricated 3D 1H3N current collector exhibited a CE of 98 % for over 270 cycles at 0.5 mA·cm–2 and 97 % for over 220 cycles at 1 mA·cm–2. The Li@3D 1H3N anode stabilized over 270 cycles (1100 h) at 0.5C in symmetric cells and delivered a capacity retention of 92.5 % after 450 cycles at 1C (1C = 170 mAh·g–1) in full cells. This study sheds light on the multifunction modification of self-supported anode current collectors for advanced LMBs to promote their practical application.