We found that the carbonized electrode from polyvinylidene chloride (PVDC) resin had high capacitancedensity. The structure of the electrode contains more micropores and less mesopores than the general activated carbon. Its specific surface area was proved to be smaller than the general activated carbon. We fabricated electric double layercapacitors with the electrodes made by PVDC carbonization. After evaluation of the above capacitors, we made acapacitor module of 12V-100F for the experiment of engine starting. Through the experiment, we considered that theapplication for the idling stop system of motor vehicles is promising. We organized CCR corporation to develop EDLCs with organic electrolyte as well as sulfuric acid electrolyte whose characteristics were introduced in this paper. Carbon materials is a basically important factor for both electrolyte types. We hope carbon materials manufacturersto supply specific products suitable for each purposes.