Catalytic decomposition of ethylene carbonate by pyrrolic-N to stabilize solid electrolyte interphase on graphite anode under extreme conditions

Abstract

Despite the dominated anode materials of graphite for lithium-ion batteries (LIBs), the poor rate capability and inferior cyclability restain their applications under extreme conditions due to their deficient interfacial chemistry. Herein, an ultrathin but Li2CO3-rich solid electrolyte interphase (SEI) is manipulated by the decomposition of ethylene carbonate (EC) on graphite anode with nitrogenous amorphous carbon coating (denoted as GMIB-2P). Specifically, Li2CO3 can enable a decreased charge transfer resistance and faster Li+ diffusion capability. In addition, we demonstrate the catalytic effect of pyrrolic-N on graphite surface with prominent wettability induces the rapid decomposition of EC with low reaction energy barrier through density function theory (DFT) calculation. Consequently, GMIB-2P delivers an outstanding capacity retention ratio of 90.82% after 300 cycles at 1 C and an improved initial Coulombic efficiency (ICE, 90.77% vs. 85.35%). More importantly, GMIB-2P possesses durable-cycling capability even with lean electrolytes of 5 μL mg-1 and as well as 85.68% capacity retention for over 300 cycles at 60 ℃. Our work highlights the key role of EC in tailoring interfacial chemistry from structure regulations and provides new guidelines to design more reliable anodes for LIBs under extreme conditions.