METHOD FOR MANUFACTURING METALLIC AGGLOMERATED PARTICLES, METHOD FOR MANUFACTURING POSITIVE-ELECTRODE ACTIVE MATERIAL FOR LITHIUM ION BATTERY, METHOD FOR MANUFACTURING LITHIUM ION BATTERY, AND LITHIUM ION BATTERY

To obtain metal agglomerate having stable particle sizes and substantially spherical shapes, the method allows, by a circulation unit, a flow of a liquid containing metal to pass through a processing vessel and an external circulation path, and a part of the liquid from the processing vessel to be extracted to an outside in a substantially continuous manner so as to return to the processing vessel after it goes through the external circulation path, sets a flow velocity in the external circulation path to be 1 m/second or more, and injects at least a part of a liquid concentrate containing a reactant to be newly added into the external circulation path.