MANUFACTURING METHOD OF SECONDARY BATTERIES USING SI-CNFS BASED ON CO-CU CATALYSTS

摘要

The present invention relates to a method for manufacturing a secondary battery using a silicon-based carbon nanofiber composite based on a cobalt-copper binary catalyst. The method comprises the following steps: (a) forming metal catalyst powder by using a catalyst compound in which cobalt nitrate and copper nitrate are mixed at a certain weight ratio; (b) mixing the metal catalyst powder with Si particles at a one to one ratio, then stirring and drying the mixture; (c) synthesizing a carbon nanofiber by chemical vapor deposition using the catalyst powder to form a CNFs/Si composite; (d) forming a dispersion solution using the CNFs/Si composite and a binder polytetrafluoroethylene (PTFE) and dip coating a nickel foam with the dispersion solution, and then vacuum-drying to form a negative electrode active material; and (e) manufacturing a secondary battery in which a separation membrane containing an electrolyte is located between the electrodes and using the negative electrode active material as a working electrode (WE) and a Li metal as a counter electrode (CE) and a reference electrode. Thus, the present invention provides not only a method for simply and easily manufacturing a negative electrode active material for a lithium secondary battery having good electrochemical properties by the method for manufacturing Si particles and a CNFs composite using the Co-Cu binary catalyst and chemical vapor deposition, but also a method for manufacturing a high quality lithium secondary battery having high charge-discharge efficiency, high capacity, and long lifetime using the CNFs composite as a working electrode of the secondary battery.