• CNTs enhance electrochemical energy storage devices due to their exceptional electrical conductivity and structural integrity.
• Recent synthesis advances include metal-organic framework-derived CNTs and three-dimensional ordered macroporous structures.
• CNTs improve performance in lithium-ion, lithium-metal, lithium-sulfur, sodium, and flexible batteries, as well as supercapacitors.
• Challenges remain in scalability and integration, with proposed solutions and future research directions outlined.