A supercapacitor is a high-capacity capacitor that can store and deliver energy much faster than batteries and tolerate more charge/discharge cycles. It works by creating an electric double layer at the interface between the capacitor's electrodes and an electrolyte, allowing for a greater surface area and smaller separation between plates than ordinary capacitors. There are two main types: electrical double-layer capacitors that store energy via electrostatic double layers, and electrochemical double-layer capacitors that involve Faradaic reactions. Supercapacitors provide peak power, extend battery life, and enable low-temperature operation, though they have lower energy density and higher self-discharge than batteries. Common applications include vehicles, wind turbines, and backup power