Mesoporous silicon sponge as an anti-pulverization structure for high-performance lithium-ion battery anodes

Nanostructured silicon is a promising anode material for high-performance lithium-ion batteries, yet scalable synthesis of such materials, and retaining good cycling stability in high loading electrode remain significant challenges. Here we combine in-situ transmission electron microscopy and continuum media mechanical calculations to demonstrate that large (420 mm) mesoporous silicon sponge prepared by the anodization method can limit the particle volume expansion at full lithiation to similar to 30% and prevent pulverization in bulk silicon particles. The mesoporous silicon sponge can deliver a capacity of up to similar to 750 mAhg(-1) based on the total electrode weight with >80% capacity retention over 1,000 cycles. The first cycle irreversible capacity loss of pre-lithiated electrode is <5%. Bulk electrodes with an area-specific-capacity of similar to 1.5 mAhcm(-2) and similar to 92% capacity retention over 300 cycles are also demonstrated. The insight obtained from this work also provides guidance for the design of other materials that may experience large volume variation during operations.