Enhanced performance of Si-based Li-ion batteries through elastic cushioning with hollow graphene shells

Silicon (Si) is a promising anode material for next-generation Li-ion batteries. The nanometer-sized Si could alleviate the pulverization caused by large volume changes during deep cycling. However, compression between agglomerated particles causes cracking and electrode failure. Considering this, we engineered mechanical cushioning space via elastic hollow graphene shells (GSs) to flexibly buffer maintain stability of structure. stress generated from expansion lithiation was mechanically buffered gently released GS. In this Si/GS composite electrode, GS also reduced local agglomeration effectively improved overall conductivity. these advantages, designed showed an enhanced cycling performance with more than 1200 mA h g−1 at 0.8 A excellent rate capability 1025 4 after 200 cycles.