CATHODE ACTIVE MATERIAL FOR A SECONDARY BATTERY, ELECTRODE FOR A SECONDARY BATTERY AND SECONDARY BATTERY COMPRISING THE SAME, AND A PRODUCTION METHOD THEREFOR

摘要

The present invention is a cathode active material for a secondary battery, an electrode for a secondary battery and a secondary battery comprising the same, and a production method therefor. The cathode active material for a secondary battery according to the present invention is a cathode active material comprising a core carbon material wherein an edge part or the entirety has been covered with a carbide layer, and it is characterised in that the particle size distribution (PSD) broad value is between 0.1 and 0.85, and in that, when compressed under a 2 ton pressure, the void-volume ratio before and after compression is at least 0.2. The present invention makes it possible to improve the discharge capacity, the efficiency and the percentage of capacity maintained in long-term cycling by optimising the void-volume ratio of the cathode active material before and after compression, and the PSD broad value associated with the particle distribution aspect of the physical properties of carbon-based cathode active materials for secondary batteries.