Renewable energy materials have attracted much attention because of the high amount of pollution present in the environment today. One of the renewable energy technologies is to produce batteries that can provide large energy so they can replace fossil fuels. The lithium-ion battery has a combination of both high energy density and power density, so it has been widely used because of its advantages that are promising to produce high energy. Lithium titanate is the most used material as an anode for lithium-ion batteries because it has zero strain, long service life, and also safe because it tends not to form a solid electrolyte interface. However, in addition to the advantages of lithium titanate batteries, this anode has a low electrical conductivity and a relatively low capacity. One method to improve the performance of lithium- ion batteries is to modify the surface, which is to form a composite on the anode. Various elements and compounds can be combined with lithium titanate to produce composites. In this study, iron oxide from production waste was used with variation in the amount as an ingredient to form LTO/Fe2O3 composite. The result of each composites' characteristics was observed to determine the effect of iron oxide levels on the performance of lithium-ion batteries. The addition of iron oxide to LTO was aimed to form a composite that increases battery capacity and its electrical conductivity.