Aluminum Solid Electrolytic Capacitor Research Articles

Structure and Electric Properties of Anodized Aluminum with PEDOT:PSS Conductive Polymer Cathode

Aluminum solid electrolytic capacitors using a conductive polymer as a cathode material has the advantages of low equivalent series resistance (ESR) and high thermal stability compared to aluminum electrolytic capacitors using liquid electrolytes. A disadvantage of aluminum solid electrolytic capacitors with a conductive polymer is the low breakdown voltages, limiting the operating voltage of the capacitors to ∼100 V or less. In this study, for a possible future increment of the withstand voltages of solid electrolytic capacitors, PEDOT:PSS-coated aluminum with an amorphous or crystalline alumina layer formed at 500 V has been characterized using SEM, STEM/EDS, and conductive AFM to understand the distribution of PEDOT:PSS conductive polymer and its influence on the electric properties. The crystalline alumina layer, developed beneath a porous hydrated alumina layer, contains many voids, which increase the leakage current compared to the void-less amorphous alumina layer. However, the crystalline alumina layer with PEDOT:PSS exhibits a higher breakdown voltage than the amorphous one. The limited incorporation of PEDOT:PSS into the inner part of the porous hydrated alumina layer may introduce a resistive surface layer, possibly contributing to the increased dielectric breakdown.

Reducing of the Equivalent Series Resistance by the Addition of a Solvent in a Conductive Polymer Aluminum Solid Electrolytic Capacitor

Reducing of the Equivalent Series Resistance by the Addition of a Solvent in a Conductive Polymer Aluminum Solid Electrolytic Capacitor

PH-Tunable High-Performance PEDOT:PSS Aluminum Solid Electrolytic Capacitors

The pH effect of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) water dispersion on colloidal particle size (D50), zeta potential (ζ), and electrical conductivity was investigated. An increase in the pH of the PEDOT:PSS water dispersion from 2 to 11 increased the D50 from 10 to 100 nm owing to the aggregation of the colloidal particles and decreased the electrical conductivity from 750 to 62 S cm–1 by dedoping, respectively, while the ζ remained almost constant at ca. – 50 mV. Furthermore, aluminum solid electrolytic capacitors were fabricated using PEDOT:PSS as a cathode material. It was found that the electrical characteristics of the PEDOT:PSS aluminum solid electrolytic capacitors were optimized at pH 3, where D50 and electrical conductivity played an important role for low equivalent series resistance (ESR) and high capacitance (Cap). Furthermore, the ESR decreased and Cap increased by repeating the fabrication process, where the Cap usable rate reached as high as 92% because o...

Characterization of CNT–pyrolytic C-layer-coated Al foil: interfacial structures, reactions, and performances

Al foil coated with CNT–pyrolytic C layer of 300 nm (CNT-C/Al) was obtained by heating Al foil coated with CNTs and polymeric precursors in rolls at 580 °C. In CNT-C/Al, distribution of species containing C and Al in depth and crystal structures of these species were investigated by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The results reveal that there are diffusion of Almetal and Al x O y to CNT-C layer and chemical reactions of carbon with Al x O y and Almetal at interface, resulting at Al–O–C and Al–C, respectively, which are clarified to be Al4O4C and Al4C3, respectively. Comparison experiments of CNT-C/Al and CNT-C/Al-control (control sample with Al4C3 undetected) show that interface reactions can improve coating adhesion and promote electrical performances of CNT-C/Al effectively. Aluminum solid electrolytic capacitors using CNT-C/Al display ESRs of 5 ± 0.5 mΩ and capacitances of 460–500 μF, in comparison with 8–50 mΩ and 400–500 μF, respectively, for the control samples. Outstanding long-time stabilities of the capacitors as well as CNT-C/Al are also presented with 94–97% retention of the initial capacitance and less than 15% increase in ESR after 1000 h in accelerated lifetime test at 125 °C.

Study of the Aluminum Anode Oxide Film and Cathode Material Interface of Conductive Polymer Aluminum Solid Electrolytic Capacitor

Introduction In 1745, Lyden jar was invented by J.Sesaguliers and Peter Van Muchenbroek. In1855, It was discovered by Charles Weatstone capable of forming an insulating film on the surface of the electrode. (By this discovery, we can make the electrolytic capacitor.) Aluminum electrolytic capacitor, was made by GE, Inc in 1908. And about 1931, aluminum electrolytic capacitor has been commercialized in the United States. Current, aluminum electrolytic capacitor is used in a power supply and noise reduction and an inveter. Electrolytic capacitor has a large equivalent series resistance and electricity is wasted. So, having a small equivalent series resistance, conductive polymer aluminum solid electrolytic capacitors are in practical use. However, conductive polymer aluminum solid electrolytic capacitor, to the leakage current is larger, the withstand voltage is low. It is desirable that this drawback is eliminated. It should be made clear disadvantages mechanism. It seems to be difficult when using typical electrochemical cell. This study was carried out by devising the cell. Experiments, Results and Discussion The anode oxide film even if contaminated with carbon in a conductive polymer was repaired. As a result, the conductive polymer has been shown that increasing the insulating film of the anode oxide film. A conductive polymer aluminum solid electrolytic capacitors made of aluminum foil and a separator, as compared with the electrolytic solution cathode electrolysis capacitance, equivalent series resistance decreases. equivalent series resistance was reduced, especially 10kHz ~ 100kHz. Anodic aluminum after being anode oxidation, affixed a reinforcement seal. It was added dropwise to the electrolyte solution into the hole of the reinforcement label. Put the counter electrode and measured cyclic voltammetry without separator. This experiment shows, the anode oxide film showed it to be damaged by a separator.

The effects of hyperbranched poly(siloxysilane)s on conductive polymer aluminum solid electrolytic capacitors

An aluminum solid electrolytic capacitor, using poly-(3,4-ethylenedioxythiophene) (PEDOT) as a counter electrode, was prepared with hyperbranched poly(siloxysilane)s (HBPSi) that has a large number of vinyl groups to improve the interfacial properties between aluminum oxide and PEDOT. Capacitance and equivalent series resistance (Rs) were significantly improved compared to untreated oxide film and vinyl terminated polydimethylsiloxane coated interfaces. From electrochemical measurement of the withstand voltage, damage to the oxide film from chemical polymerization of PEDOT was less with the HBPSi treatment. Frequency characteristics and electrical conductivity measurements of the polymer indicated that the resistance inside the etched porous layer was greatly reduced. These results show that the HBPSi pre-coating layer inhibited degradation of the oxide film by chemical polymerization of PEDOT and the conductivity of PEDOT in the etched porous oxide layer, and also enlarges the contact area by improving interfacial adhesion.

Modification of Anodized Aluminum Film by Hyperbranched Poly(siloxysilane)s in Conductive Polymer Aluminum Solid Electrolytic Capacitor

Abstract An aluminum solid electrolytic capacitor, using poly(3,4-ethylenedioxythiophene) (PEDOT) as a counter electrode, was prepared with hyperbranched poly(siloxysilane)s (HBPSi) to improve an interface of aluminum oxide and PEDOT. Capacitance and equivalent series resistance (ESR) were significantly improved comparing to those without HBPSi.

Aluminum Solid Electrolytic Capacitors with Functional Polymer, PX/PXA Series(Reliability of the Electric Components)

Aluminum Solid Electrolytic Capacitors with Functional Polymer, PX/PXA Series(Reliability of the Electric Components)

Aluminum Solid Electrolytic Capacitors with Functional Polymer

Aluminum Solid Electrolytic Capacitors with Functional Polymer

Polyaniline electrolytic capacitator

Aluminum solid electrolytic capacitors with polyaniline doped with inorganic and organic acids as counterelectrode were fabricated, their properties were studied.

高融点TCNQ錯塩の開発とそれを用いたアルミ電解コンデンサ

高融点TCNQ錯塩の開発とそれを用いたアルミ電解コンデンサ

Stability study of polypyrrole and application to highly thermostable aluminum solid electrolytic capacitor

This paper describes the stability of electropolymerized polypyrrole and a highly thermostable aluminum solid electrolytic capacitor in which polypyrrole is applied as an electrolyte. We found that polypyrrole doped with tri-i-propylnaphthalenesulfonate (PPy/TIPNS) shows excellent thermostability and its conductivity decay stems from the addition reaction of oxygen followed by thermal decomposition in which oxygen participates. On the basis of these results, we developed a highly thermostable aluminum solid electrolytic capacitor which is composed of an etched and anodized aluminum foil anode covered with electropolymerized PPy/TIPNS and is hermetically sealed. The capacitor continuously functioned for more than 3600 h at 150 °C without any deterioration. Moreover, the capacitor also showed ideal impedance-frequency characteristics comparable to those of the multilayer ceramic capacitor and flat temperature characteristics in the wide range of −50 to 150 °C.

An aluminum solid electrolytic capacitor with an electroconducting-polymer electrolyte

A new type of aluminum solid electrolytic capacitor in which electroconducting polymer is applied as an electrolyte was developed. It was found that polypyrrole doped with alkylnaphthalenesulfonate (PPy/ANS) offers excellent thermal and moisture stabilities. By providing an etched and anodized aluminum foil electrode with a thin layer of pyrolytic manganese dioxide, higher coverage with electrochemically synthesized polypyrrole was accomplished. The newly developed capacitor not only has good frequency and temperature characteristics but also has good thermal and moisture stabilities.

Aluminum solid electrolytic capacitor with organic semiconductor

This paper deals with the new organic semiconductor which offers high electrical conductivity and high thermal stability after the melting process. By impregnating a capacitor element with this organic semiconductor, the wound element type aluminum solid capacitor was developed. In the following paper the molecular structure and physical properties of the new organic semiconductor are described along with description of frequency and temperature characteristics, life, etc. of the newly-developed capacitor.

Hybrid Microcircuitry for 300°C Operation

Microelectronic instrumentation for geothermal well logging must operate in ambient temperatures up to 300°C for several hundred hours. This study involved an extensive survey of 25 to 300°C operation of resistors, capacitors, conductors, interconnections, and active devices. Three major selection criteria were: 1) part lifetime of at least 1000 h at 300°C; 2) minimum change in electrical parameters from 25 to 300°C; 3) availability to the common circuit builder (no one of a kind). Certain thick film resistors, capacitors, and conductors were found compatible with such high-temperature operation. In addition, reconstituted mica and aluminum solid electrolytic capacitors were found useful up to 300°C. Simple circuits for a geothermal temperature logging tool have been fabricated using these hybrid materials, components, and Si MOS and JFET devices. Oven tests show satisfactory stability from 25 to 300°C and at least 100-h circuit operation at 300°C.

Alternating‐Current Properties of Organic Semiconductor Solid Capacitor

This paper deals with the a‐c properties of a new type of aluminum solid electrolytic capacitor in which organic semiconductors are employed as the counterelectrode. Both equivalent series capacitance and resistance (ESR) were measured between 90 Hz and 22 MHz frequencies and their temperature dependence was determined between −55° and +85°C. Excess series capacitance and ESR which were introduced by the use of the organic semiconductor counterelectrode were separated analytically, and the origin of the impedance connected in series of the anodic oxide is discussed. Very stable a‐c properties were observed in the high frequency and low temperature regions, which permitted explanation of the a‐c properties with simple models, such as a distributed circuit or dispersions owing to various interfaces. In the low frequency region, the capacitance and ESR increased with decreasing frequency and increasing temperature. It is suggested that the low frequency dissipation is dominated by the interfacial polarization due to polymer binder in contact with the anodic oxide.

Miniaturized Aluminum Solid Electrolytic Capacitors Using a Highly Effective Surface Enlargement Technique

This paper describes a new method for increasing the anode area and hence the capacitance density of aluminum solid electrolytic capacitors. Frequency, temperature, voltage, and life characteristics of the improved capacitors are pre- sented.

An Aluminum Solid Electrolytic Capacitor with an Organic Semiconductor Electrolyte

This paper describes the development and characteristics of a new aluminum solid electrolytic capacitor in which organic semiconductors are substituted for manganese dioxide. The highly conductive ion-radical salts based on 7, 7, 8, 8-tetracyanoquinodimethan were chosen because of their prominent effect on capacitor self-healing. The solid electrolyte layer of a thin uniform coating was deposited from a solution of the semiconductor and polymers. A basic approach to obtaining a uniform and adherent film suitable for an etched aluminum foil is given, along with limitations on the use of the organic semiconductor. Emphasis is placed on the effect of the polymers on the growth and adsorption of the organic-semiconductor crystals during electro formation. Much improvement was realized in capacitor performance, viz. the Iow leakage current, the extended ratio of breakdown-to-formation voltage, and stable frequency characteristics. It may be concluded from the laboratory experiments that production of high-performance organic semiconductor solid capacitors will probably be feasible in the near future

New Method of Manufacturing Sintered‐Type Aluminum Solid Electrolytic Capacitor

not Available.