Section 1 Introduction Chapter 1 Polymer blend nanocomposites: Fundamentals, preparation, and characterization Chapter 2 Fundamental mechanisms and requirements of energy storage materials Section 2 Types of polymer blend nanocomposites in applications for energy storage Chapter 3 Elastomeric polymer blend nanocomposites for energy storage applications Chapter 4 Thermoplastic-based polymer blend nanocomposites for energy storage Chapter 5 Thermosetting-based blend polymer nanocomposites for energy storage Chapter 6 Biodegradable polymer blend nanocomposites for energy storage application Chapter 7 Polymer blend nanocomposite electrolytes for advanced energy storage applications Section 3 Polymer blend nanocomposites with various fillers for energy storage applications Chapter 8 Polymer blend nanocomposites with CNTs for energy storage applications Chapter 9 Graphene-based polymer blend nanocomposites for energy storage applications Chapter 10 Polymer blend nanocomposites of fullerene for energy storage Chapter 11 Polymers with carbon-based quantum dots for energy storage Chapter 12 Polymer blend nanocomposites with metal-based nanomaterials for energy storage Chapter 13 Polymer blend nanocomposites with hybrid nanomaterials for energy storage Section 4 Applications of polymer blend nanocomposites in energy devices Chapter 14 Polymer blend nanocomposites for capacitor applications Chapter 15 Polymer blend nanocomposites for supercapacitor applications Chapter 16 Polymer blend nanocomposites for battery applications Chapter 17 Polymer blend nanocomposites for polymer electrolyte membrane fuel cell (PEMFC) applications Chapter 18 Polymer blend nanocomposites for solar cell applications Section 5 Lab to industry, recycling, and life cycle assessment Chapter 19 Polymer composites for energy storage: Commercialization, lifecycle assessment, and recycling