LITHIUM-ION SECONDARY BATTERY AND METHOD OF PRODUCING SAME

摘要

The present invention provides a lithium-ion secondary battery which decreases the resistance of a positive electrode and a negative electrode , provides a high capacity when the battery is charged and discharged at a high electric current, has a long life, and is inexpensive. MEANS FOR SOLVING THE PROBLEM In a positive-electrode material for a lithium-ion secondary battery containing carbon black, olivine-type lithium iron phosphate coated with a carbon material, and a fibrous carbon material; and a negative-electrode material for the lithium-ion secondary battery containing a graphite carbon material coated with the carbon material as its main material, the carbon black, and the fibrous carbon material; the carbon black is mixed with a positive-electrode material containing the lithium iron phosphate or the carbon black is mixed with a negative-electrode material containing the graphite carbon material to pulverize positive-electrode powder and negative-electrode powder by utilizing a shearing force to be generated by a mechanochemical method or the like and uniformly disperse and mix respective particles with one another. Thereafter the fibrous carbon material dispersed in a water solution is added to the powders and mixed therewith to form a mixture. Thereafter a binder containing a water-soluble or water-dispersible synthetic resin is added to the mixture.