Rationally engineered amorphous TiOx/Si/TiOx nanomembrane as an anode material for high energy lithium ion battery

Energy density is the main performance indicator of lithium ion batteries (LIBs) that has driven the entire technology forward over the past decades. However, the current LIBs cannot meet the ever-increasing energy storage demand. Herein, a stable lithium-ion full battery with high energy density of 525 Wh kg-1 has been demonstrated, using a newly designed 3D amorphous TiOx/Si/TiOx nanomembranes (NMs) as the anode. The Li+ penetrable and electron conductive TiOx coating on the Si surface effectively improves the e-/Li+ transportability and enhances the structural stability of the TiOx/Si/TiOx NMs. The nanoscaled multi-winding membranes provide shortened pathway for rapid e-/Li+ transport, and empty channels allowing for free volume expansion of the Si without mechanical breaking. As a result, the customized TiOx/Si/TiOx NMs display improved lithium storage performance with high initial coulombic efficiency (ICE), long cycle life and excellent rate capability. When pairing this special anode with a commercial LiNi1/3Co1/3Mn1/3O2 (NCM) cathode, the TiOx/Si/TiOx-NCM full-battery delivers good cycling stability, excellent power capability and, most remarkably, an unprecedented improvement in the gravimetric energy density. Therefore, it is believed that this unique TiOx/Si/TiOx nanomaterials may hold promise for the next-generation LIBs with high energy density.