FM Supercapacitors KEMET FM Supercapacitors, also known as electric double-layer capacitors (EDLCs), are designed for high-energy storage applications. These supercapacitors are capable of producing 3.5VDC, 5.5VDC, and 6.5VDC voltages. The capacitors operate in a wide range of temperatures from -25°C to +70°C (all types except FMR) and -40°C to +85°C (FMR type). KEMET FM Supercapacitors are maintenance free and highly reliable against liquid leakage. The series comes in a rectangular case with leads that can be transverse-mounted.