With rising global oil prices and global warming, energy crisis poses a threat to living standards, societal security, economy, and even global environment. Advanced functional materials, including polymer nanocomposites, have begun to play an unprecedented role in our ultimate objective of sustainable and clean energy production, energy transportation, storage, and end usage. A number of developments and achievements in polymer nanocomposites have been documented during the past decade; however, a focus on applications of functional polymer nanocomposites for energy storage and conversion has not yet been covered in previous ACS symposium series books. This book will present frontier scientific research and technologies in polymer nanocomposites for energy storage and conversion from international and U.S. academic institutions and industries in recent years. Its authors seek to enlighten the future development and directions of polymer nanocomposites for energy storage and conversion. Focusing on three contemporary energy topics - electric energy storage, fuel cells, and photovoltaics, this book endeavors to enhance the national awareness of the feasibility and importance of polymer nanocomposites for energy storage and conversion.