The lithium-ion battery recycling process has been classified into direct recycling, hydrometallurgical process, and pyrometallurgical process. The commercial process based on the hydrometallurgical process produces black mass through pretreatment processes consisting of dismantling, crushing and grinding, heat treatment, and beneficiation, and then each metal is recovered by hydrometallurgical processes. Since all lithium-ion battery recycling processes under development conducts hydrometallurgical processes such as leaching, after the pretreatment process, to produce precursor raw materials, this article suggests a classification method according to the pretreatment method of the recycling process. The processes contain sulfation roasting, carbothermic reduction roasting, and alloy manufacturing, and the economic feasibility of the lithium-ion battery recycling process can be enhanced using unused by-products in the pretreatment process.