Engineering hollow multi-shelled Co3O4 cubes to boost lithium storage performance

To solve the low conductivity and huge volume change of cobalt-based anode, the tuneable Co 3 O 4 structure is constructed through a template-free hydrothermal strategy and calcination under different atmosphere. Multi-shelled Co 3 O 4 (MS-Co 3 O 4 ) and pomegranate-like Co 3 O 4 encapsulated in carbon (CS-Co 3 O 4 @C) are fabricated from the same micron-sized cobalt-based polymeric precursor. MS-Co 3 O 4 manifests a capacity of 1195 mAh·g −1 at a current density of 200 mA·g −1 and delivers an initial coulombic efficiency (ICE) of 80.3%. In addition, CS-Co 3 O 4 @C delivers a reversible capacity as high as 676 mAh·g −1 at 2000 mA·g −1 after 500 cycles. Such high capacity, remarkable cycling and rate performances are attributed to hollow multi-shelled structure and carbon network skeleton, which promote the initial coulombic efficiency, relieve volume change and facilitate the migration of Li-ion.