Electrochemical energy storage refers to the process of storing energy in the form of chemical energy through electrochemical reactions. This technology is commonly used in devices like batteries and supercapacitors, which convert electrical energy into chemical energy during charging and release it during discharging. These systems are essential for managing energy supply and demand, especially in renewable energy applications like solar and wind power. By storing excess energy generated during peak production times, electrochemical energy storage helps ensure a stable and reliable energy supply when production is low.