A contactwire-less railcar driven by an Mn type lithium ion battery was developed and the energy-saving effects were examined. The relations between running time and voltage, current, and integrating watt were investigated in detail in a running test conducted on the flat Mikuni and sloping Katsuyama lines of the Echizen railway. The railcar ran when the lithium ion battery module was discharged between 660 V and 490 V. On one charge, the railcar could run for more than 20 km. The running performance of the contactwire-less railcar was comparable to that of the contactwire railcar.
Noble metal particles such as Ag and Pd were deposited site-selectively on Si substrate using colloidal crystal composed of polystyrene spheres as a mask for electroless plating to obtain metallic honeycomb pattern. After metal-assisted chemical etching of Si in HF/H2O2, ordered Si convex arrays were formed. On the other hand, isolated-island metal pattern was obtained on Si substrate by hydrophobic treatment with colloidal crystal templating, which acted as a mask for subsequent electroless plating. Si hole arrays formed after chemical etching corresponded to inverse structure of above-mentioned Si convex arrays. The dimensions of the resultant pattern could be adjusted with feature sizes ranging from 3 µm to 200 nm by changing the diameter of the polystyrene spheres used as an initial mask.
A wet process for forming an adhesive Cu layer on polyimide (PI) film was developed. In this process, the surface of the PI film is pretreated in plasma, followed by the formation of a ligand-bearing organic layer of 3-aminopropyltriethoxy silane (APTES) molecules. After catalyzation with a solution containing Pd ions, thin layers of NiB as the underlayer and that of Cu as the conductive layer are deposited by electroless depositions, and then a 10 µm thick Cu layer is electrodeposited. The peel strength of the specimen prepared by this method was found to depend on the morphology of the NiB underlayer. A continuous NiB layer functions as a barrier layer that prevents Cu from contacting the PI film. In the presence of this efficient barrier layer, the peel strength was found to improve after annealing at 150°C.
Nanocarbons with brush-type morphology have been prepared by liquid phase carbonization of poly(acrylamide) (PAA) or poly(vinylchloride) (PVC) in pores of template. The template used is dc etched aluminum foil that is further anodized in sulfuric acid electrolyte. The nanocarbons derived from PAA contain nitrogen, whose content decreases with increasing heat treatment temperature. At each heat treatment temperature, the specific surface area as well as pore structure is similar for both the nanocarbons derived from PAA and PVC. Nevertheless, the markedly large electrochemical capacitance, measured in 1 mol dm−3 sulphuric acid, is obtained for the PAA-derived nanocarbons, compared with that from PVC, due to pseudocapacitance arising from nitrogen species in the former nanocarbons. Despite the specific surface area of less than 250 m2 g−1, the PAA-derived nanocarbons reveal the capacitance as large as ∼130 F g−1. The capacitance per specific surface area is found to increase almost linearly with the content of nitrogen. It is also found that the capacitance per specific surface area of the nanocarbons with the brush-type morphology is larger than that of the carbon nanofilaments prepared similarly using a template of porous anodic alumina on plain aluminum foil.
We have succeeded to make a Li metal thin film in the range of 1–20 µm on copper foil or plastic thin film by gas-deposition method. The Li thin films showed almost the same discharge capacity as a conventional Li metal foil made by roll-pressing method. Alloy thin film electrode of a Sn-35 mass%Cu also has been prepared on copper film by the gas-deposition method. The gas-deposited electrode showed much higher capacity retention ratio (87% after 50 cycles) than the conventional pasted electrode (20% after 50 cycles). The initial irreversible capacity loss of roughly 30% in the alloy electrode have been suppressed successfully by pre-doping of lithium in the alloy electrode using the lithium thin film prepared on the plastic sheet.