Polymer capacitors are laminated sheet aluminum electrolytic capacitors with high-conductivity polymer material as cathode. Polymer capacitors have superior electrical performance than liquid sheet aluminum electrolytic capacitors and solid sheet tantalum electrolytic capacitors. The polymer capacitor is within the rated voltage range, so it does not require step-down use. This kind of capacitors are mainly used in electrical motherboard, bypass decoupling/energy storage filter capacitor, switching power supply, DC/DC converter, high-frequency noise suppression circuit and portable electronic equipment.