Organosilane Plasma Enhanced Interfacial Engineering to Boost Inorganic‐Rich Hybrid Solid Electrolyte Interface for Advanced Lithium Metal Batteries

The design and development of high-performance artificial solid-electrolyte interphase (SEI) are crucial for constructing advanced lithium metal anodes, as they critically stabilize the electrode-electrolyte interface. Herein, a facile plasma-enhanced interfacial engineering strategy to construct a robust inorganic-rich hybrid SEI on Li metal anodes using octamethyltrisiloxane (OMTS) plasma is reported. This process forms a hybrid SEI layer comprising primarily an inner inorganic-rich layer (e.g., Li₂SiO₃, Li₂CO₃, Li_xSi) and an outer organic-rich layer (lithium compounds). The formation mechanism is attributed to interfacial reactions between Li and OMTS plasma-generated radicals. Theoretical calculations demonstrate that this designed inorganic-rich hybrid SEI effectively regulates Li⁺ transport and promotes uniform Li deposition, thereby suppressing Li dendrite growth. Consequently, symmetric Li|| Li cells equipped with the modified anodes achieve stable cycling for 700 h at 1 mA cm^-2 and 1 mAh cm^-2. Furthermore, when paired with an LFP cathode, the full cells exhibit significantly enhanced high-rate capability and superior cycling stability, retaining 97.8% capacity after 800 cycles at 7.5C. This work provides a plasma interfacial engineering route for constructing advanced alkali metal anodes.