The process for the site-controlled formation of tunnel pits with high aspect ratios by anode etching of Al͑100͒ foil is described.Introduction of a small amount of Cu on the Al foil, which has a patterned thin layer of polymers, initiated the uniform development of pits and generated the tunnel pits with sufficiently high aspect ratios. The obtained ordered array of tunnel pits with high aspect ratios will be used for the preparation of several types of functional devices in addition to the improvement of electrolytic capacitors, which use the Al foil with tunnel pits as a surface-enlarged electrode.Formation of tunnel pits on Al by the anisotropic anode etching of Al͑100͒ foils in an electrolyte containing Cl − ions has been widely used for the enlargement of the surface area of electrodes in electrolytic capacitors. 1-10 To maximize the capacitance of the electrolytic capacitors, the size and interval of the tunnel pits must be controlled precisely by considering the operating voltages. 1 In our previous report, we showed the control of the initiation sites of the tunnel pits using a patterned mask composed of a polymer film on Al. 11 In this process, a very thin patterned mask of poly͑chloro-prene͒ rubber ͑CR͒ with the thickness of ϳ200 nm formed on Al can be used to control the initiation of tunnel pits at the initial stage of the anode etching of Al. However, tunnel pits with sufficient depth could not be formed due to the preferential growth of the tunnel pit in the lateral directions. In the present report, we show the process for the formation of tunnel pits with sufficiently high aspect ratios. For the uniform growth of tunnel pits with high aspect ratios, we introduced a small amount of Cu on an Al surface as an initiator for the uniform development of tunnel pits. The uniform development of the pits effectively improved their growth with uniform depth, and yielded the tunnel pits with sufficiently high aspect ratios. The obtained ordered array of tunnel pits on Al prepared by the present process will be used for the fabrication of various types of functional devices in addition to the improvement of the capacitance in electrolytic capacitors. Figure 1 shows the process for the fabrication of highly ordered tunnel pits with high aspect ratios on Al. A patterned mask composed of a polymer film placed on Al with the ͑100͒ plane ͑Ͼ95%͒ was formed using a process reported previously. 11 A thin patterned mask of CR was formed using a poly͑dimethylsiloxane͒ ͑PDMS͒ stamp, which has an ordered hole array. Diameter, depth and interval of holes of the stamp were 1.5, 1.5, and 5.0 m, respectively. Size of the stamp was typically 6 ϫ 6 mm. Before making a patterned mask, an Al foil was electrochemically polished in a mixed solution of perchloric acid and ethanol. Then, a small amount of Cu was formed on the surface of Al by vacuum evaporation or sputtering. The amount of deposited Cu was controlled using a quartz crystal thickness monitor. Electrochemical etching of Al was carried out under a constant-current cond...
SDX ® which is surface coated aluminum current collector (AL) with carbon black and organic binder, makes a cell resistance lower and adhesion between cathode active material and AL stronger, so as to improve battery performances dramatically. The cell resistance was separated simply into electronic resistance and ionic resistance. We successfully separated the electronic resistance into material resistance and interface resistance between cathode active material and AL. And then, we independently measured the material resistance and the interface resistance by Electrode Resistance Meter (HIOKI E.E. CORPORATION) which can separate electrode resistance into material and interface resistance. In this paper, more detailed examinations were carried out, and the mechanism of decreasing resistance by SDX ® in lithium ion battery (LIB) was tried to be clarified.
SDX ® which is surface coated aluminum current collector (Al) with carbon black and organic binder, makes a cell resistance lower and adhesion between cathode active material and Al stronger, so as to improve battery performances dramatically. The cell resistance was separated simply into electronic resistance and ionic resistance. We successfully separated the electronic resistance into material resistance and interface resistance between cathode active material and Al. And then, we independently measured the material resistance and the interface resistance by Electrode Resistance Meter (HIOKI E.E. CORPORATION) which can separate electrode resistance into material and interface resistance. In this paper, more detailed examinations were carried out, and resistance reduction effect by SDX ® in lithium ion battery (LIB) was tried to be clarified.
Akifumi TAKEDA-ーーーー * 1Haruyuki YAMAMOTO-ーー * 2 This paper presents the results of pile construction work for two steelframe buildings. These buildings incorporate a method proposed by the authors in which the bottom end of a steel column is directly connected to the top end of a precast concrete pile. This method, which was developed for the construction of low-rise, long-span, steel-frame buildings, obviates the need for pile caps and underground beams. This method, however, requires greater accuracy in pile construction than is required with conventional construction methods. Hence, a stringent construction control value was specified for the work, and the outcome satisfied this value. This paper presents the results of pile construction work for two steel-frame buildings. These buildings incorporate a method proposed by the authors in which the bottom end of a steel column is directly connected to the top end of a precast concrete pile. This method, which was developed for the construction of low-rise, long-span, steel-frame buildings, obviates the need for pile caps and underground beams. This method, however, requires greater accuracy in pile construction than is required with conventional construction methods. Hence, a stringent construction control value was specified for the work, and the outcome satisfied this value.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.