This paper presents a case study conducted by Isuzu Technical Center of America on calculating Lithium-ion battery degradation patterns. For hybrid electric cars, plug-in hybrid electric vehicles (PHEVs), and all-electric vehicles, energy storage technologies, and batteries are often necessary (HEVs). As soon as these batteries are used for the first time, they begin to deteriorate. This is due to the battery's inherent chemistry which results in inevitable chemical reactions that happen inside the battery while it is running. ISUZU engineers are using the GT-AutoLion tool to predictively model the electrochemical processes within Lithium-ion cells using a fast and reliable, electrochemical, physics-based approach and real-world battery information. To feed this tool, we gathered valuable battery information from a light-duty BEV Prototype. The information was recorded at 3 different milestones: BOT (beginning of the test), 7500 miles, and 15000 miles. After analyzing this data at each milestone, it is observed that the battery was degraded by 8.09% after a 7500-mile run and decreased significantly to 10.42% of overall battery capacity at 15k miles, such similar patterns were also observed in the developed battery model, The battery degradation patterns generated by the developed battery model will be used to predict battery performance and improve range estimation by ISUZU.