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The storage behavior of Li ions in the anode limits the energy density of full cell. Storing entirely as Li ions sacrifices energy density while storing entirely as Li metal shortens cycle life. The hybrid behavior maximizes both energy density and lifespan through good anode candidate and interface engineering. In this work, Li ions storage is tailored in carbon film (CF) as a hybrid Li‐ion/metal to reduce Li metal consumption at low N/P ratios. A series of weakly solvating electrolytes are screened to enhance the Li intercalation ability of the CF anode while inducing highly reversible Li metal plating/stripping. Among them, 1 m LiFSI‐THF‐0.5 wt.%LiNO3 electrolyte achieves a low interfacial energy barrier, allowing the CF anode not only to have the highest intercalation capacity of 236.5 mAh g−1, but also to exhibit excellent cycling stability and high Coulombic efficiency, even at fast charging and low temperature. The NCM811||CF full cell with a low N/P ratio of 0.5 delivers a capacity of 527.3 mAh g−1 at 25 °C, and 381.5 mAh g−1 at −20 °C, achieving energy densities of 312.6 and 223.7 Wh kg−1, respectively. 100 mAh pouch cell can be cycled stably over 500 cycles, with a capacity retention of 83.0%. [ABSTRACT FROM AUTHOR]

• A new morphology of carbon plates were synthesized using natural mushroom spores. • The carbon plates exhibit nano-graphitic layers with a suitable d 002 -spacing (0.371 nm). • The carbon plates for Na+ storage exhibit outstanding specific capacity at low potential plateau (< 0.1 V vs. Na+/Na). • Natural spores with well-defined morphologies provide a vast platform for developing low cost and efficient carbon materials for Na+ storage. Biomass derived hard carbon has been considered a sustainable solution for sodium ion storage to improve the energy density of sodium ion batteries for low cost and large-scale energy storage. However, developing this kind of carbon materials with high specific capacity at low-potential platform is a critical issue. Herein, a new structure of hard carbon plate was developed via pyrolysis of mushroom spore (Ganoderma lucidum). The spore is mainly composed of chitin, distinguished from the lignin and cellulose in widely investigated biomass. The carbon plates obtained at 1400 °C have a suitable d 002 -spacing (0.371 nm) and ultra-low surface area down to 14.7 m2 g−1, resulting in a high reversible total discharge capacity of 305.8 mA h g−1 with an exceptional discharge capacity of 188.0 mA h g−1 at low-potential platform (0–0.1 V vs. Na+/Na) and excellent cycle stability as anode for SIBs. Meanwhile, the proportion of low-potential capacity in total capacity is 61.5%, which is significantly superior to previously reported carbon materials prepared using biomass from advanced plants. Furthermore, a full-cell constructed using the carbon plates as anode and sodium vanadate phosphate as cathode further validates the outstanding Na+ storage performance at low-potential, in which the battery delivers a high working voltage of 3.25 V, approaching the discharge potential of 3.3 V of sodium vanadate phosphate and a considerable energy density of 199.2 W h kg−1 (based on the total mass of cathode and anode). And it is also revealed that this high capacity for Na+ storage in the low potential range is attributed to the intercalation mechanism of NaC 6 as the most possible intercalation compound. The hard carbon derived from natural spores in the work presents a new route to design low cost and efficient carbon materials as advanced anode for SIBs. Image, graphical abstract [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-N-CNT-CF is fabricated by growth Co-MOF and a straightforward CVD process. • DFT results confirm Co@G and N-CNT provide multitudinous lithiophilic sites. • Co-N-CNT-CF substrate exhibits outstanding electrochemical performance. Lithium (Li) metal is an impeccable candidate anode for satisfying the energy density requirements of next-generation Li batteries. However, Li dendritic growth and fragile solid-elecrolyte interphase (SEI) caused by the high reactivity between Li and electrolyte are the primary challenges for its large-scale applications. Herein, a bifunctional lithiophilic hierarchical substrate composed of high-density nitrogen-doped carbon nanotubes and Co nanoparticles encapsulated in graphene (Co@G) decorated carbon fibers (Co-N-CNT-CF) can modulate the structural dimensions and hierarchy of Li nucleation/growth and alleviate Li volume expansion, achieving the homogeneous Li plating/stripping behavior. Density functional theory (DFT) calculations and experimental results confirm the highly lithiophilicity of the substrate, which exhibits a low Li nucleation overpotential, enhanced Coulombic efficiency (CE), small voltage hysteresis, and ultrastable lifespan without dendritic formation. As coupled with the thick LiFePO 4 and LiCoO 2 (∼2 mA h cm−2) cathodes, the Co-N-CNT-CF@Li composite anode (N/P = 3) enables a high reversible capacity, high Li utilization, and improved cycle stability. This work engineers a hierarchical structure of the three-dimensional (3D) lithiophilic carbon substrate for realizing highly reversible, dendritic-free Li metal anodes. [ABSTRACT FROM AUTHOR]