Micron SiOx encapsulated into amorphous B, N Co-doped carbon nanotube network for high-capacity and long-durable Li-ion half/full batteries

•Encapsulation of m-SiOx into amorphous B, N co-doped carbon nanotubes is designed.•The composite is prepared via a facile metal-assisted self-assembly method.•The in-situ grown nanotubes provide fast Li+/e− transfer and moderate volume change.•The composite possesses ultrahigh capacity and prominent cycle stability.