Techno-Economic Comparison of Vehicle-To-Grid and Commercial-Scale Battery Energy Storage System: Insights for the Technology Roadmap of Electric Vehicle Batteries

With the rapid growth of renewable energy integration, battery energy storage technologies are playing an increasingly pivotal role in modern power systems. Among these, electric vehicle distributed energy storage systems (EV-DESSs) using vehicle-to-grid technology and commercial battery energy storage systems (BESSs) exhibit substantial potential for user-side energy storage applications. A comparative analysis of the cost competitiveness between these two types of energy storage systems is crucial for understanding their roles in the evolving power system. However, existing studies lack a unified framework for techno-economic comparisons between EV-DESSs and commercial BESSs. To address this research gap, we conduct a comprehensive, technology-rich techno-economic assessment of EV-DESSs and commercial BESSs, comparing their economic feasibility across various grid services. Based on the technical modeling, this research simulates the operational processes and the additional battery degradation of EV-DESSs and commercial BESSs for providing frequency regulation as well as peak shaving and valley filling services. Building on this foundation, the study evaluates the cost competitiveness and profitability of both technologies. The results indicate that the levelized cost of storage (LCOS) of EV-DESSs and commercial BESSs ranges from 0.057 to 0.326 USD/kWh and from 0.123 to 0.350 USD/kWh, respectively, suggesting significant overlap and thus intense competition. The benefit–cost ratio of EV-DESSs and commercial BESSs ranges from 26.3% to 270.1% and from 19.3% to 138.0%, respectively. Battery cost and cycle life are identified as the key factors enabling EV-DESSs to outperform commercial BESSs. This drives a strong preference for lithium iron phosphate (LFP) batteries in V2G applications, allowing for LCOS reductions of up to 4.2%–76.3% compared to commercial BESSs across different grid services. In contrast, ternary lithium-ion batteries exhibit weaker cost competitiveness in EV-DESSs compared to commercial BESSs. While solid-state and sodium–ion batteries are promising alternatives, they are less competitive in V2G applications due to higher costs or a shorter cycle life. These findings highlight the superiority of LFP batteries in current V2G applications and the need to align cost, cycle life, and safety performance in the development of next-generation battery chemistries.