Preparation method of cobaltosic oxide-carbon porous nanofiber and application of cobaltosic oxide-carbon porous nanofiber to preparation of lithium ion battery

The invention discloses a preparation method of a cobaltosic oxide-carbon porous nanofiber and application of the cobaltosic oxide-carbon porous nanofiber to preparation of a lithium ion battery. The preparation method comprises the steps of dropwise adding a sol solution of soluble cobalt salt into a dimethylformamide solution of polyacrylonitrile and polymethyl methacrylate, continuously stirring, and keeping at the temperature of 80-100 DEG C for 24 hours; preparing a polymer/cobalt salt composite fiber supported on aluminum foil by using an electrostatic spinning process; heating the polymer/cobalt salt composite fiber to 280 DEG C at the rate of 2-4 DEG C/min in air, and keeping heating for 2 hours; and then, heating to 500 DEG C in the presence of inert atmosphere, keeping heating for 4 hours, and then, cooling to obtain the cobaltosic oxide-carbon porous nanofiber. The composite material has nano-scale size and high conductivity; when the cobaltosic oxide-carbon porous nanofiber is used as a negative electrode material of a lithium battery, the cycle life of the lithium battery can be prolonged, and the rate capability of the lithium battery can be improved; in addition, the preparation method is simple in process, good in repeatability, easy to implement and beneficial to industrial production.