As the production of lithium-ion batteries (LIBs) increases, the need for the raw materials grows at a rate that may either exceed the annual supply available or become cost prohibitive under present formulations. Recycling components from depleted LIB systems represents an alternative feedstock to meet predicted the demand for raw materials and provides a market for used batteries. A large component of the cost of LIBs come from the metals used in the cathode and the fluoride salts used in the electrochemical cells and being able to reuse these materials is of critical importance. End of life LiNi_0.33Mn_0.33Co_0.33O₂ (NMC111) cathodes are typically 15-20% lower in lithium content than fresh cathode. The goal is to return the cathode back to the starting composition through direct chemical relithiation without causing change to the structure. This direct recycling process retains most of the energy already invested in creating the cathode creation by maintaining as much of the structure as possible. Baseline NMC cathodes were chemically delithiated to known concentrations (15-25% removal) by treatment with (NH₄)₂S₂O₈. A chemical approach to cathode relithiation by heating delithiated NMC with different lithium sources (Li₂CO₃, LiOH, Li₂O) taking into account thermal stability windows and the emergence of Li/Ni antisite mixing will be described in this presentation. Samples were characterized by powder XRD, scanning electron microscopy, GDOES, ICP and electrochemical evaluation.