This paper presents the student's manufacture activity of a racing Electric Vehicle (EV) which is a very small size and single rider type for participate ECO-RUN Race in Sugo Japan. The racing EV requires a light body weight, small wind resistance, high electric energy efficient, etc. to achieve a good score in the ECO-RUN racing tournament in Sugo. Not only power electronics but also mechanical design and manufacture technique have been demanded. In this paper, firstly, the Ibaraki National College of Technology (INCT) of EV project team will be introduced. Next, the mechanical manufacture process and designed power circuit mainly bidirectional DC-DC converter in order to introduce Super Capacitor (EDLC; Electric Double Layer Capacitor) to EV will be presented. Furthermore, the new approach system which is a series or parallel changeover system using battery with EDLC for assist power in short term is proposed. Finally, the experimental result of the power circuit in Sugo racing circuit will be presented.