Current research on electrochemical energy is mostly interested in developing new materials and relevant engineering techniques. In a fundamental perspective, electrochemical energy storage/conversion is a complex dynamic process that involve a wide range of length and time scales. In this regard, a lot of puzzles still exist. Spectroscopy, which is all about interaction between light and matter, has resolved numerous puzzles in different areas of physical science. Using spectroscopy to thoroughly interrogate energy storage/conversion processes could lead to discovery of new phenomena or principles, especially on how information of electronic and vibrational states is associated with dynamics of energy storage. The obtained knowledge will serve as new discoveries in fundamental physical science.