Although lithium metal is considered a promising anode for advanced Li-S and Li-air batteries, the uncontrolled dendrite growth and infinite volume change impede its practical application. Herein, we report an ideal framework composed of carbonized bacterial cellulose (CBC) nanofibers, which shows intrinsic lithiophilicity to molten lithium without any lithiophilic surface modification. The wetting behavior of molten lithium can be significantly improved because its surface functional groups provide thermodynamical driving force, and the high surface roughness derived from nanocracks leads to rapid infusion in kinetics. The hybrid anode exhibits long cycle life up to 2000 h and excellent deep stripping–platting capacity up to 20 mAh·cm⁻². When the anode is assembled with LiFePO₄ cathode, the full cell delivers a good cycling stability up to 700 cycles. This is attributed to the intrinsic lithiophilic scaffold, which can not only lower the nucleation barrier of Li and provide uniform nucleation sites for stable Li stripping/plating, but also offer interspace to accommodate volume fluctuation of lithium during long cycling. This work provides a new manner to achieve a series of intrinsic lithiophilic carbon skeletons based on the large family of biomass materials and organic materials.

Cobalt oxide (Co₃O₄) is currently suitable in energy storage applications because of its high capacity based on the conversion reaction mechanism. However, unmodified Co₃O₄ suffers from distinctly inferior rate capability and poor cycling stability. On the basis of the aforementioned considerations and density functional theory (DFT) simulations, the three-dimensional hierarchical porous structure (HPS) ultrasmall Co₃O₄ anchored into ionic liquid (IL) modified graphene oxide (GO) has been successfully prepared (ultrasmall/Co₃O₄-GA-IL). The ultrasmall/Co₃O₄-GA-IL consists of Co₃O₄ co-assembled with IL modified GO to generate the HPS which can facilitate ion transfer channels through reduction of the electron and ion transportation path and transmission impedance. In addition, N-doping graphene can enhance the inherent electrical conductivity of Co₃O₄, which is proved by the DFT calculations. By virtue of the novel superstructure, the ultrasmall/Co₃O₄-GA-IL electrode demonstrates a high reversible capacity of 1,304 mAh·g⁻¹, an enhanced high-rate capability (715 mAh·g⁻¹ at 5 C), and a capacity retention of 98.4% even after 500 cycles at 5 C rate, which corresponds to 0.0003% capacity loss per cycle. Pouch cells based on the cathode are further fabricated and demonstrate excellent mechanical and electrochemical properties under bent and folded state, highlighting the practical application of our deliberately designed electrode in wearable electronics.