Electrochemical refers to the branch of chemistry that deals with the relationship between electricity and chemical reactions. It involves processes where chemical energy is converted into electrical energy, or vice versa. Common examples include batteries, where chemical reactions produce electricity, and electrolysis, where electrical energy drives a chemical reaction. In electrochemical systems, ions move through an electrolyte, facilitating the transfer of electrons. This movement is essential in devices like fuel cells and supercapacitors, which are used in various applications, from powering electric vehicles to storing renewable energy. Understanding electrochemical principles is crucial for advancements in energy technology.