This study investigates the market dynamics of Tesla and NIO in the electric vehicle (EV) industry, with a focus on NIO's innovative Battery as a Service (BaaS) model and its pricing strategy. While NIO’s competitive pricing attracts buyers, the study reveals that its low vehicle and battery prices negatively impact profitability. The research also identifies NIO's recent market share decline and the challenges posed by its pricing model. From a sustainability perspective, the study highlights the significant freshwater usage in the manufacturing processes of both Tesla and NIO, stressing that this places a strain on local water resources. To contribute meaningfully to emission reduction, the optimization of water recycling and energy efficiency in manufacturing is crucial. The analysis provides insights into NIO's declining market share and offers suggestions for future market participation.