Composite solid electrolytes hold the promise of merging complementary merits of solid polymer electrolytes and ceramic fillers to achieve solid batteries with comprehensive performance. Especially, three-dimensional inorganic electrolyte frameworks, such as Li₇La₃Zr₂O₁₂, with fast and continuous lithium ion migration channels demonstrate great promise in composite solid electrolytes. Nevertheless, brittle ceramic conductor skeletons are incapable of providing sufficient mechanical adaptability, which restricts their practical application. Herein, a flexible, ion-conducting network which integrates Li₇La₃Zr₂O₁₂ nanoparticles in polyacrylonitrile nanofibers is fabricated through electrospinning method. Subsequently, a composite electrolyte with three-dimensional continuous structure is achieved via in situ polymerizing of 1,3-dioxolane within the ionic conduction framework. The highly conductive Li₇La₃Zr₂O₁₂ reinforced polymer nanofibers are not only available to promote transportation of lithium ion, but also provide structural flexibility and mechanical robustness for composite electrolyte. Accordingly, the obtained composite electrolyte combines enhanced room temperature ionic conductivity (4.38 × 10⁻⁴ S·cm⁻¹) with structural flexibility and mechanical robustness, supported by exceptional interfacial compatibility with lithium metal, enabling ultra-stable lithium symmetric battery operation (3000 h at 0.1 mA·cm⁻²). Furthermore, as-prepared LiFePO₄ and LiCoO₂/lithium solid-state batteries deliver high capacity retention of 96% after 350 cycles and capacity retention of 82% after 600 cycles at room temperature. This work provides a new avenue in design of advancing composite solid electrolytes.

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.

With the growing strategic position of near-space vehicles, the demand for energy storage batteries with high power, high specific energy, and long cycle life has also increased. Lithium metal battery with ultra-high theoretical specific energy is a promising candidate for the next-generation energy storage system of near-space vehicles. Lithium metal exhibits extremely low reduction potential and high theoretical capacity, but its application is limited by issues associated with dendrite growth. In this paper, based on oxidation etching and ion exchange mechanism, a three-dimensional (3D) Au-CuO nanowire array current collector on copper foam (CF) (Au-CuO/CF nanoarray 3D current collector) was successfully prepared via the preparation of CuO nanowire array on CF and the introduction of Au as lithophilic sites. This current collector was then applied as a lithium metal battery anode. Compared to the CuO/CF nanoarray 3D current collector, the Au-CuO/CF nanoarray 3D current collector demonstrated significantly improved Coulombic efficiency, cycle life, and cycling stability. When paired with a lithium iron phosphate (LFP) cathode, the full cell achieved a capacity retention of 97.7% after 700 cycles. The Au-CuO/CF nanoarray 3D current collector features simple preparation and excellent electrochemical performance, with the full cell demonstrating outstanding cycling stability and exceptional capacity retention, showing great potential as a next-generation high-energy-density lithium metal battery anode current collector.

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.