It is challenging to create cation vacancies in electrode materials for enhancing the performance of rechargeable lithium ion batteries(LIBs).Herein,we utilized a strong alkaline etching method to success-fully create Co vacancies at the interface of atomically thin Co3-xO4/graphene@CNT heterostructure for high-energy/power lithium storage.The creation of Co-vacancies in the sample was confirmed by high-resolution scanning transmission electron microscope(HRSTEM),X-ray photoelectron spectroscopy(XPS)and electron energy loss near-edge structures(ELNES).The obtained Co3-xO4/graphene@CNT deliv-ers an ultra-high capacity of 1688.2 mAh g-1 at 0.2 C,excellent rate capability of 83.7％capacity retention at 1 C,and an ultralong life up to 1500 cycles with a reversible capacity of 1066.3 mAh g-1.Reaction kinetic study suggests a significant contribution from pseudocapacitive storage induced by the Co-vacancies at the Co3-xO4/graphene@CNT interface.Density functional theory confirms that the Co-vacancies could dramatically enhance the Li adsorption and provide an additional pathway with a lower energy barrier for Li diffusion,which results in an intercalation pseudocapacitive behavior and high-capacity/rate energy storage.