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 (>20 μm) mesoporous silicon sponge prepared by the anodization method can limit the particle volume expansion at full lithiation to ~30% and prevent pulverization in bulk silicon particles. The mesoporous silicon sponge can deliver a capacity of up to ~750 mAh g −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