This paper delves into the critical materials supply chain of the battery market with an emphasis on long-term energy security. The study recognizes electric vehicle battery packs as reservoirs of “locked reserves” for extended periods, typically 10 years or more. A comprehensive understanding of material flows and end-of-life battery management is essential to establish a sustainable, durable, and secure domestic supply chain for lithium-ion batteries. In addressing these concerns, the paper introduces a metric designed to assess the “per mile” consumption of critical reserves called “Materials Per Gallon-Electric (MPGe)”. The study emphasizes the immediate need for critical materials to meet the accelerated demand for large-scale electric vehicle adoption in the short term. Furthermore, the paper also emphasizes the urgent need to advance recycling technologies to recover the critical mineral reserves “locked” in end-of-life battery packs.