With the increasing demand for electric vehicles, battery recycling is becoming a critical topic for lowering the environmental impact of wasted batteries. Hydrometallurgical recycling is a widely used method, and the cathode leaching process is essential for hydro metallurgical recycling. This work comprehensively compares leaching processes for LCO, NMC, and LFP cathodes using life cycle assessment. Different leaching processes use different acids, leaching temperatures, and reaction times. A score is calculated based on the environmental impact of the leaching process and the recycling rates of all valuable metals. This score can help identify the best leaching process for obtaining the most valuable metals with the least environmental impact. From this study, we conclude that 2M sulfuric acid with hydrogen peroxide is the best leaching solution for LCO, 2M sulfuric acid with hydrogen peroxide is the best leaching choice for NMC, and 3M sodium persulfate is the best leaching process for LFP.