In Situ Forming a Black Phosphorene Mixed Ion/Electron Conductor Layer by External Pressure without Binder for Anode-Free Li Metal Batteries

Anode-free Li metal batteries are an excellent choice for developing the next generation of high-energy-density battery systems. However, due to poor chemical compatibility between the current collector and electrolyte interface, the Li electrodeposition on current collectors faces a huge challenge of rapid capacity degradation in anode-free Li metal batteries. Herein, a strategy for modifying an ultrathin black phosphorene (BP) mixed ion/electron conductor interface layer on the surface of a current collector by relying on pressure is proposed. The BP hybrid interface layer is formed in situ on the surface of the current collector solely by pressure compared with traditional current collector modification technology, and there is no powder shedding phenomenon in the absence of a binder. Moreover, the Cu-NCM811 cell matched with high mass loading cathodes exhibits excellent capacity retention and an average Coulombic efficiency of 99.1%. The relevant result has established the foundation for the development of long cycling anode-free Li metal batteries.