There is an ongoing major transition to low-carbon energy worldwide, which makes energy systems more dependent on critical metals (e.g., rare-earth elements, cobalt, etc.). The need to secure a stable supply of those critical metals for emerging energy technologies has attracted global attention. In this context, it becomes increasingly important to explore the metal-energy nexus and identify corresponding strategies. This chapter introduces the context, framework, implementation, and implications of the mineral-energy nexus in the global energy transition, and highlights the importance and necessity of incorporating material cycles into this framework. Under the guidance of this nexus perspective, we then explore the global metal cycles of 18 types of energy-critical metals and investigate their key concerns. To guarantee a successful energy transition, there is a strong need to incorporate the metal system into energy policy making, and this chapter urges stakeholders throughout the material cycle to take actions and promote more sustainable and collaborative production, consumption, trade, and recycling of those energy-related metals.