Multi-hierarchical earbuds-ball-like silicon suboxide-carbon hybrids design for high-performance lithium storage

Silicon suboxide (SiO x ) is considered a promising substitute for silicon (Si) anode materials in lithium-ion batteries due to its high specific capacity (>2200 mAh g −1 ) and improved cycling performance. However, its volume expansion (∼200%) and low conductivity cannot be ignored. Here, inspired by earbuds, we design and mass synthesize (240 g h −1 ) the earbuds-like three-dimensional SiO x nanonetworks (3D-SiO x NNs) by a radio-frequency thermal plasma (RF-plasma) system. The spray drying technology is used to further accelerate the winding of 3D-SiO x NNs to prepare micron-sized multi-hierarchical earbuds-ball-like SiO x /C (E-SiO x /C) with enhanced elasticity and high tap density. As anodes, E-SiO x /C exhibits the high gravimetric/volumetric specific capacity of 1790 m Ah g −1 /1137 m Ah cm −3 and excellent rate cycling performance (1480 m Ah g −1 at 2.0 A g −1 for 700 cycles). In addition, full battery constructed with LiNi 0.5 Co 0.2 Mn 0.3 O 2 cathode exhibit high gravimetric energy density of 530.9 Wh kg −1 and impressive cycling performance (513.9 Wh kg −1 for 100 cycles), manifesting great promise for the application of high-performance batteries.