METHOD FOR PREPARING NANO CHEMICAL MANGANESE DIOXIDE (CMD) FOR CATHODE MATERIAL OF SECONDARY BATTERY BY USING RECIRCULATION PROCESS AND NANO CHEMICAL MANGANESE DIOXIDE (CMD) PREPARED THROUGH SAME

摘要

The present invention relates to: manufacturing a manganese dioxide seed (seed-MnO₂) in powder by heat treating a manganese carbonate (MnCO₃) for industrial use; pulverizing the manganese dioxide seed into a nano powder manganese dioxide seed, wherein a primary particle is nano-sized; performing acid treatment on the nano powder manganese dioxide seed; preparing the nano powder manganese dioxide seed into a manganese dioxide seed in a more uniform powder in which foreign material is removed; and prepares a primary chemical manganese dioxide (CMD1) by growing, on the surface of the nano manganese dioxide seed, homogenous crystals of nano chemical manganese dioxide (CMD) used as a precursor of a cathode material of a secondary battery. At this time, by recirculating a reaction solution separated to obtain the primary chemical manganese dioxide (CMD1) in powder, the reaction solution is utilized as a reaction mother solution for manufacturing a secondary chemical manganese dioxide (CMD2) and a tertiary chemical manganese dioxide (CMD3), thereby increasing the manganese dioxide yield in the whole reaction process, mass-producing the manganese dioxide, using the manganese dioxide as the precursor of a cathode material of a lithium secondary battery, and further enhancing the charging and discharging efficiency of the lithium secondary battery using the manganese dioxide as the cathode material.