A Li metal-SiOx hybrid anode enabling synergistic plating/alloying dual-mechanism lithium storage.

Balancing specific energy and cycle durability remains a critical challenge for practical battery systems, as conventional single-mechanism anodes struggle to optimize both simultaneously. Here, we engineer a symbiotic Li-SiOx hybrid anode enabling spatiotemporally coordinated Li metal plating and Li-ion alloying. The preferential lithiated LixSi forms a Li+-conductive network, guiding and confining lithium nucleation beneath the SiOx layer. This precise control over Li plating replenishes active lithium inventory, stabilizing electrochemical reactions and minimizing Li loss. When paired with a LiNi0.8Co0.1Mn0.1O2 cathode (4 milliampere-hours per square centimeter), the full cell achieves 50% higher specific energy than SiOx-based lithium-ion batteries while retaining 80% capacity after 900 cycles at a lean negative/positive ratio of 1.5, outperforming state-of-the-art Li-ion and Li-metal battery systems. A pouch cell exhibits stable cycling over 600 cycles at 0.5C, validating its practicality. Our findings pioneered a universal hybrid anode design paradigm with coupled reaction mechanisms, effectively addressing the longstanding energy durability trade-off in next-generation batteries.