The invention relates to a novel electrochemical capacitor. The electrochemical capacitor comprises a microprocessor, a capacitor temperature detection circuit, a zero crossing detection circuit, a BL8203, a pulse transformer, an SPI bus, a power failure detection circuit, a human-machine interaction interface module, a 485 communication circuit, a first RJ45 communication port, an electric energy measurement circuit, a second RJ45 communication port, an electric current signal sensing circuit and a combination switching circuit. According to the novel electrochemical capacitor provided by the invention, the latest achievements of microelectronic hardware and software technology, micro-sensor and micro-network technology are adopted, and are successfully applied to a low-voltage reactive compensation capacitor, and low-voltage reactive automatic control function, zero-crossing switching, power failure protection, electric energy measurement, communication networking, fault self-diagnosis and other functions are realized. The novel electrochemical capacitor can be used flexibly in various occasions of low-voltage reactive power control, changes the structure model of the existing low-voltage reactive automatic control equipment, and has the advantages of simple structure, easiness in production, cost reduction, performance improvement, and easiness in maintenance.