3D Printed Sodium-Ion Batteries via Ternary Anode Design Affording Hybrid Ion Storage Mechanism

Sodium-ion batteries (SIB), as one of the most appealing grid-scale energy storage devices, have to deal with the trade-off between the capacity output and rate performance. Utilizing 3D-printed (3DP) anode materials with hybrid sodium storage mechanism and elevated mass loading is promising yet poorly explored. Herein, the design of a prototype ternary composite is reported, MoS2@Bi/N-doped carbon, as a sodium storage candidate to achieve high reversible capacity (604 mAh g-1 at 0.1 A g-1 with an initial output of 709 mAh g-1) and outstanding rate capability (169.6 mAh g-1 at 15 A g-1), outperforming the state-of-the-art reports. This is realized by delicate structural and interfacial engineering of the composite anode, markedly synergizing the conversion-typed MoS2, alloy-typed Bi, and adsorption-typed N-doped carbon. Theoretical simulations and operando instrumental analysis elaborate the reasons of the boosted electrochemical performance. Encouragingly, a fully 3DP SIB affording an areal mass loading of up to 11.7 mg cm-2 is demonstrated, retaining a capacity of 114 mAh g-1 at 1.0 A g-1. This work would facilitate the design of 3DP SIB devices with the employment of advanced electrodes harnessing hybrid ion storage features. imageHe enhance sodium storage performance by integrating various sodium storage mechanisms, including alloy-based, conversion, and adsorption/desorption types, while designing material morphology. This addresses volume expansion in alloy-based materials and instability in transition metal sulfides, resulting in outstanding performance in half-cells. Utilizing 3D printing, he precisely modulate the electrode structure, maintaining excellent sodium storage even under high loads in full-cell tests.