Carbonization behavior of polyimide mixed with nickel compounds was investigated.The carbonization behavior of polyimide was altered by nickel compounds added at the precursor stage. The size of nickel metal crystal which was given by reduction of the nickel compounds at the early stage of polyimide carbonization varied as well below the heat-treatment temperature of 600°C. However, the size of nickel crystal afterheat-treatment at 800°C and the crystal parameters of turbostratic carbon developed by the catalytic effects of nickel metal were independent of the original nickel compounds and the same values were given for all nickel containing samples.

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Polyaniline (PANT)-intercalated graphite oxides (GOs) were synthesized and theirelectrochemical properties were investigated. Surfactant-intercalated GO dispersed in N-methyl-2-pyrrolidone (NMP) reacted with various amounts of PANI solution in NMP, giving intercalation compounds with I_c values of 1.1nm or 1.3nm. The absorption peak at 2900cm^-1 derived from C-H group in surfactant was not observedin the IR spectra of the obtained intercalation compounds. This indicated that surfactants intercalated into GO layer were completely replaced by PANI via ion exchange reaction. The charge-discharge curve of the intercalation compound with I_c value of 1.1nm was similar to that of GO at the first cycle and to that of PANI at the subsequent cycles. However, it was different from that of the physically mixed GO/PANI composites. The discharge capacity at the 10th cycle for the above intercalation compound was 80 mAh/g.

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Spherical and hard carbon particles containing ZnO at highly dispersed state were prepared by carbonizing an ion-exchange resin exchanged by Zn²⁺. They were subjected to the evaluation of antibacterial activity against the growth of S. aureus. It was found that the antibacterial activity increased with increasing amount of the carbon particles in an incubation cell.

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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.

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Electric double-layer capacitors based on the charge storage at the interface between a high surface area activatedcarbon electrode and an organic electrolyte solution have been developed, and are widely used as maintenance-freepower source for IC memories and microcomputers. Electric double-layer capacitors exhibit in principle unlimited cyclelife and maintenance free operation as an alternative to batteries in power circuits. One of the new promising applicationfor electric double-layer capacitor is a pulse power source in electric and hybridvehicle application. The pulse powersource provides the peak power during acceleration and recovers energy during braking using a generator. The popularityof these devices is derived from their high energy density compared with conventional capacitors and their long cycle life and high power density relative to batteries. The performance of the capacitor depends not only on materials usedin the cells but also on the construction of the cells. Energy density of electricdouble-layer capacitors reported atpresent is more than 3.5Wh/kg at a power density of 500W/kg.

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