Antipulverization Electrode Based on Low-Carbon Triple-Shelled Superstructures for Lithium-Ion Batteries

The realization of antipulverization electrode structures, especially using low-carbon-content anode materials, is crucial for developing high-energy and long-life lithium-ion batteries (LIBs); however, this technology remains challenging. This study shows that SnO₂ triple-shelled hollow superstructures (TSHSs) with a low carbon content (4.83%) constructed by layer-by-layer assembly of various nanostructure units can withstand a huge volume expansion of ≈231.8% and deliver a high reversible capacity of 1099 mAh g⁻¹ even after 1450 cycles. These values represent the best comprehensive performance in SnO₂-based anodes to date. Mechanics simulations and in situ transmission electron microscopy suggest that the TSHSs enable a self-synergistic structure-preservation behavior upon lithiation/delithiation, protecting the superstructures from collapse and guaranteeing the electrode structural integrity during long-term cycling. Specifically, the outer shells during lithiation processes are fully lithiated, preventing the overlithiation and the collapse of the inner shells; in turn, in delithiation processes, the underlithiated inner shells work as robust cores to support the huge volume contraction of the outer shells; meanwhile, the middle shells with abundant pores offer sufficient space to accommodate the volume change from the outer shell during both lithiation and delithiation. This study opens a new avenue in the development of high-performance LIBs for practical energy applications.

SnO₂ triple-shelled hollow superstructures with a low carbon content (4.83%) can withstand a huge volume expansion of ≈231.8% and deliver a high reversible capacity of 1099 mAh g⁻¹ even after 1450 cycles, due to their self-synergistic structure-preservation behavior that protects the superstructures from collapse and guarantees the electrode structural integrity during long-term cycling.

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