Dynamically lithium-compensated polymer artificial SEI to assist highly stable lithium-rich manganese-based anode-free lithium metal batteries

Owing to the unique structure, anode-free lithium metal batteries (AFLMBs) have higher energy density and lower production cost than traditional lithium metal batteries (LMBs) or lithium-ion batteries (LIBs). However, AFLMBs suffer from an inherently finite Li reservoir and exhibit poor cycle stability, low Coulombic efficiency (CE) and severe dendrite growth. In this work, polydiallyl lithium disulfide (PDS-Li) was successfully synthesized and coated on Cu current collector by electrochemical polymerization. The PDS-Li acts as an additional lithium resource to compensate for the irreversible loss of lithium during cycling. In addition, the special structure and lithiophilicity of PDS-Li contribute to lower nucleation overpotential and uniform lithium deposition. When coupled with Li-rich manganese-based (LRM) cathode of Li1.2Mn0.54Ni0.13Co0.13O2, the anode-free full cell exhibits significantly improved cycle stability over 100 cycles and capacity retention of 63.3