WO2026029005A1 - Feuille d'électrode, condensateur électrolytique et procédé de production de feuille d'électrode - Google Patents

Feuille d'électrode, condensateur électrolytique et procédé de production de feuille d'électrode

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Publication number
WO2026029005A1
WO2026029005A1 PCT/JP2025/026708 JP2025026708W WO2026029005A1 WO 2026029005 A1 WO2026029005 A1 WO 2026029005A1 JP 2025026708 W JP2025026708 W JP 2025026708W WO 2026029005 A1 WO2026029005 A1 WO 2026029005A1
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WIPO (PCT)
Prior art keywords
porous portion
electrode foil
dielectric layer
main surface
foil
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Pending
Application number
PCT/JP2025/026708
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English (en)
Japanese (ja)
Inventor
満久 吉村
宗史 門川
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Panasonic Intellectual Property Management Co Ltd
Original Assignee
Panasonic Intellectual Property Management Co Ltd
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Filing date
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Application filed by Panasonic Intellectual Property Management Co Ltd filed Critical Panasonic Intellectual Property Management Co Ltd
Publication of WO2026029005A1 publication Critical patent/WO2026029005A1/fr
Pending legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
    • H01G9/004—Details
    • H01G9/04—Electrodes or formation of dielectric layers thereon
    • H01G9/048—Electrodes or formation of dielectric layers thereon characterised by their structure

Definitions

  • This disclosure relates to electrode foil, electrolytic capacitors, and methods for manufacturing electrode foil.
  • the electrode foil of an electrolytic capacitor comprises a metal foil containing a valve action metal and having a porous portion on its main surface, and a dielectric layer covering the porous portion.
  • the porous portion increases the surface area of the electrode foil, thereby enabling a higher capacitance.
  • Patent Document 1 proposes an electrode foil for aluminum electrolytic capacitors in which aluminum foil that has been subjected to a surface expansion process by etching is compressed in the foil thickness direction, thereby increasing the surface area per unit volume compared to before compression.
  • an electrode foil with a withstand voltage of 7 V or less comprising a metal foil having a porous portion on a main surface thereof and a dielectric layer covering the porous portion, the metal foil including a valve action metal, and having an indentation depth H of 17 ⁇ m or less when a maximum indentation load of 500 mN is applied to the main surface having the porous portion covered with the dielectric layer, as measured by nanoindentation.
  • an electrode foil with a withstand voltage greater than 7 V and equal to or less than 22 V comprising a metal foil having a porous portion on a main surface thereof and a dielectric layer covering the porous portion, the metal foil including a valve action metal, and an indentation depth H measured by nanoindentation at a maximum indentation load of 500 mN on the main surface having the porous portion covered with the dielectric layer of 13.5 ⁇ m or less.
  • an electrode foil having a withstand voltage greater than 22 V and equal to or less than 160 V comprising a metal foil having a porous portion on a main surface thereof and a dielectric layer covering the porous portion, the metal foil including a valve action metal, and an indentation depth H of 10.5 ⁇ m or less when a maximum indentation load of 500 mN is applied to the main surface having the porous portion covered with the dielectric layer, as measured by nanoindentation.
  • an electrolytic capacitor comprising a capacitor element, the capacitor element comprising a wound body and an electrolyte, the wound body being configured by winding an anode foil, a cathode foil, and a separator disposed between the anode foil and the cathode foil, the anode foil being the above-described electrode foil.
  • Still another aspect of the present disclosure relates to a method for manufacturing an electrode foil used in an electrolytic capacitor with a withstand voltage of 7 V or less, the method comprising: an etching step of etching a sheet containing a valve metal; a compression step of compressing the etched sheet in the thickness direction to form porous portions on the main surface of the sheet; and a chemical conversion treatment of the compressed sheet to form a dielectric layer that covers the porous portions, wherein the indentation depth H measured by nanoindentation is 17 ⁇ m or less when a maximum indentation load of 500 mN is applied to the main surface having the porous portions covered with the dielectric layer.
  • Still another aspect of the present disclosure relates to a method for manufacturing an electrode foil having a withstand voltage greater than 7 V and not greater than 22 V, the method comprising: an etching step of etching a sheet containing a valve metal; a compression step of compressing the etched sheet in the thickness direction to form porous portions on a main surface of the sheet; and a chemical conversion treatment of the compressed sheet to form a dielectric layer that covers the porous portions, wherein the indentation depth H measured by nanoindentation is 13.5 ⁇ m or less when a maximum indentation load of 500 mN is applied to the main surface having the porous portions covered with the dielectric layer.
  • a further aspect of the present disclosure relates to a method for manufacturing an electrode foil having a withstand voltage of more than 22 V and not more than 160 V, the method comprising: an etching step of etching a sheet containing a valve metal; a compression step of compressing the etched sheet in the thickness direction to form porous portions on a main surface of the sheet; and a chemical conversion treatment of the compressed sheet to form a dielectric layer that covers the porous portions, wherein the indentation depth H measured by nanoindentation is 10.5 ⁇ m or less when a maximum indentation load of 500 mN is applied to the main surface having the porous portions covered with the dielectric layer.
  • This disclosure makes it possible to improve the reliability of electrolytic capacitors.
  • FIG. 1 is a cross-sectional view schematically illustrating an example of an electrode foil according to an embodiment of the present disclosure.
  • FIG. 1 is a cross-sectional view schematically illustrating an example of an electrolytic capacitor according to an embodiment of the present disclosure.
  • FIG. 2 is a perspective view schematically illustrating the configuration of a wound body.
  • An electrode foil according to an embodiment of the present disclosure includes a metal foil having a porous portion on a main surface thereof and a dielectric layer covering the porous portion.
  • the metal foil includes a valve metal.
  • the dielectric layer covers the surface of the metal skeleton that constitutes the porous portion.
  • the electrode foil can be used in an electrolytic capacitor.
  • the indentation depth H is 17 ⁇ m or less.
  • the indentation depth H is 13.5 ⁇ m or less.
  • the indentation depth H is not more than 10.5 ⁇ m.
  • the indentation depth H is the indentation depth measured using the nanoindentation method when the maximum indentation load is 500 mN on the main surface of the electrode foil (the main surface of the metal foil having a porous portion covered with a dielectric layer).
  • the withstand voltage is determined in accordance with the Electronic Industries Association of Japan standard test method for electrode foil for aluminum electrolytic capacitors (EIAJ RC-2364A).
  • an electrode foil with high tensile strength and high capacity can be obtained.
  • Using this electrode foil can improve the reliability of electrolytic capacitors.
  • Increasing the pit density and thickness of the porous portion can be considered as a way to increase the surface area in order to achieve higher capacitance.
  • increasing the pit density and thickness reduces the strength of the electrode foil, which can lead to cracks and breaks in the electrode foil during the manufacturing process of electrolytic capacitors.
  • the reduction in electrode foil strength is due to a reduction in the strength of the surface layer of the porous portion, which is covered by the dielectric layer, and this reduction in surface strength is particularly noticeable when the pit density and thickness of the porous portion are high.
  • the following factors (a) to (c) are presumed to be factors that cause a decrease in strength of the surface layer of the porous portion covered with the dielectric layer.
  • the surface layer is likely to deteriorate due to contact of the etching solution with the surface of the metal foil during electrolytic etching.
  • the stress generated when winding the electrode foil (chemically processed foil) during the manufacturing process of an electrolytic capacitor is likely to be large in the surface layer. This stress is large, for example, when the diameter of the roller that winds the electrode foil (chemically processed foil) is small. Furthermore, this stress is larger on the outer periphery side of the wound electrode foil (chemically processed foil) than on the inner periphery side.
  • Rolled foils are usually used for raw material sheets containing valve metals (e.g., aluminum foils), and these have rolling marks, which are likely to remain on the surface layer of electrode foils (chemically processed foils).
  • the indentation depth H can be adjusted by the thickness of the compressed porous portion, the thickness of the dielectric layer covering the porous portion, etc. It can also be adjusted by the conditions of the etching process (such as the amount of dissolution of the sheet surface), the conditions of the compression process (such as the compression rate), and the conditions of the anodization process (such as the anodization voltage), which will be described later.
  • the indentation depth H can be adjusted to some extent by the etching conditions, but with high-capacity electrode foils that have thick porous layers, it is difficult to adjust it to the above range using the etching conditions alone.
  • Electrode foils (chemically formed foils) in which a dielectric layer is formed on the surface of a metal foil (porous portion) is important. Electrode foils with a dielectric layer of a predetermined thickness are used depending on the electrode foil's withstand voltage (the rated voltage of the electrolytic capacitor). For example, electrode foils with a thicker dielectric layer are used for high withstand voltages (rated voltages). The indentation depth H, etc., also varies depending on the thickness of the dielectric layer (chemically formed film).
  • Electrode foils (chemically formed foils) with high withstand voltages (chemically formed voltages) have a thicker dielectric layer (chemically formed film) and a higher proportion of dielectric (e.g., aluminum oxide). Furthermore, the pit diameter of the porous portion may be large. These factors can increase the brittleness of the foil. Embrittlement increases hardness, but on the other hand, the foil becomes brittle, which may result in a decrease in bending strength, making it necessary to increase the strength level of the electrode foil. Based on the above findings, the inventors conducted extensive research and discovered that by setting the indentation depth H within a specific range depending on the withstand voltage (rated voltage), it is possible to achieve both suppression of strength reduction and high capacity.
  • withstand voltage rated voltage
  • the dielectric layer may be a chemical conversion coating formed by chemical conversion treatment.
  • a chemical conversion coating of a predetermined thickness may be formed according to the withstand voltage (rated voltage). When the same metal foil is used for chemical conversion treatment, the thicker the chemical conversion coating formed, the smaller the indentation depth H tends to be.
  • the withstand voltage (film withstand voltage) of electrode foil E1 is 7V or less.
  • the dielectric layer may be a chemical conversion film formed by chemical conversion treatment.
  • the chemical conversion voltage may be, for example, 7V or less.
  • the thickness of the chemical conversion film of electrode foil E1 is, for example, 5nm or more and 15nm or less. Electrode foil E1 is used, for example, in electrolytic capacitors with a rated voltage of 6V or less (or 5V or less).
  • the withstand voltage (film withstand voltage) of electrode foil E2 is greater than 7V and less than 22V, or may be greater than 7V and less than 20V.
  • the dielectric layer may be a chemical conversion film formed by chemical conversion treatment.
  • the chemical conversion voltage may be, for example, greater than 7V and less than 22V (or less than 20V).
  • the thickness of the chemical conversion film of electrode foil E2 is, for example, greater than 15nm and less than 32nm.
  • Electrode foil E2 is used, for example, in electrolytic capacitors with a rated voltage of greater than 5V and less than 19V (or less than 16V).
  • the withstand voltage (film withstand voltage) of electrode foil E3 is greater than 22V and less than 160V, and may be greater than 70V and less than 160V.
  • the dielectric layer may be a chemical conversion film formed by chemical conversion treatment.
  • the chemical conversion voltage may be, for example, greater than 22V (or greater than 70V) and less than 160V.
  • the thickness of the chemical conversion film of electrode foil E3 is, for example, greater than 32nm and less than 220nm.
  • Electrode foil E3 is used, for example, in electrolytic capacitors with a rated voltage of greater than 16V and less than 130V.
  • the indentation depth H of the electrode foil E1 is preferably 15 ⁇ m or less, more preferably 14 ⁇ m or less, and even more preferably 12 ⁇ m or less. From the perspective of ensuring capacity, the indentation depth H of the electrode foil E1 may be 6 ⁇ m or more, or may be 8 ⁇ m or more.
  • the indentation depth H of the electrode foil E2 is preferably 12.5 ⁇ m or less, more preferably 11.5 ⁇ m or less, and even more preferably 10 ⁇ m or less. From the perspective of ensuring capacity, the indentation depth H of the electrode foil E2 may be 5 ⁇ m or more, or may be 6 ⁇ m or more.
  • the indentation depth H of the electrode foil E3 is preferably 9.5 ⁇ m or less, more preferably 8 ⁇ m or less, and even more preferably 7 ⁇ m or less. From the perspective of ensuring capacity, the indentation depth H of the electrode foil E3 may be 4 ⁇ m or more, or may be 5 ⁇ m or more.
  • the hardness X of the electrode foil E1 is preferably 67 mN/ mm2 or more, more preferably 90 mN/ mm2 or more, and even more preferably 110 mN/ mm2 or more. From the viewpoint of ensuring capacity, the hardness X of the electrode foil E1 may be, for example, 200 mN/ mm2 or less, or 160 mN/ mm2 or less.
  • the hardness X of the electrode foil E2 is preferably 110 mN/ mm2 or more, more preferably 125 mN/ mm2 or more, even more preferably 150 mN/ mm2 or more, and particularly preferably 190 mN/ mm2 or more. From the viewpoint of ensuring capacity, the hardness X of the electrode foil E2 may be, for example, 360 mN/mm 2 or less, or 300 mN/mm 2 or less.
  • the hardness X of the electrode foil E3 is preferably 180 mN/ mm2 or more, more preferably 225 mN/ mm2 or more, even more preferably 250 mN/ mm2 or more, and particularly preferably 350 mN/ mm2 or more. From the viewpoint of ensuring capacity, the hardness X of the electrode foil E3 may be, for example, 750 mN/mm 2 or less, or 650 mN/mm 2 or less.
  • Hardness X is the hardness measured by nanoindentation when the maximum indentation load on the main surface of the electrode foil (the main surface of the metal foil having a porous portion covered with a dielectric layer) is 500 mN.
  • the elastic modulus Y of the electrode foil E1 may be 6000 mN/mm 2 or more, 7000 mN/mm 2 or more, or 8700 mN/mm 2 or more.
  • the elastic modulus Y of the electrode foil E2 may be 7000 mN/mm 2 or more, 9000 mN/mm 2 or more, or 12500 mN/mm 2 or more.
  • the elastic modulus Y of the electrode foil E3 may be 12,000 mN/mm 2 or more, 15,000 mN/mm 2 or more, or 17,000 mN/mm 2 or more.
  • the elastic modulus Y is the elastic modulus measured by nanoindentation when the maximum indentation load on the main surface of the electrode foil (the main surface of the metal foil having a porous portion covered with a dielectric layer) is 500 mN.
  • the elastic modulus Y (Young's modulus) indicates how easily a material deforms, and within the elastic deformation range, the stress and strain applied to the material are generally proportional, with the elastic modulus being the proportionality constant (Hooke's Law).
  • the elastic modulus Y is an important parameter from the perspective of increasing the strength of electrode foil for electrolytic capacitors. For example, by appropriately adjusting the thickness of the etched foil (porous portion), the thickness of the dielectric layer, the compressibility, etc., it is possible to increase the hardness X and elastic modulus Y within the above ranges.
  • the indentation depth H, hardness X, and elastic modulus Y are determined using the nanoindentation method in accordance with ISO 14577-1 (2014).
  • An indenter is pressed into the main surface of the electrode foil (the main surface of the metal foil having a porous portion covered with a dielectric layer), and an indentation load is applied up to 500 mN.
  • the indentation depth when the maximum load of 500 mN is reached and held for 5 seconds is determined as the indentation depth H.
  • Measurement conditions Measuring device: Ultra-microindentation hardness tester "ENT-5" manufactured by Elionix Co., Ltd. Environmental temperature: 30°C Indenter: Berkovich type diamond indenter Test load (maximum indentation load): 500 mN Measurement points: 3 points averaged.
  • the electrode foil sample is fixed to a sample stage using STE TAPE manufactured by SHINTO PAINT.
  • the cumulative pore volume V0 (cm 3 /g), the cumulative pore volume V1 (cm 3 /g), and the cumulative pore volume V2 (cm 3 /g) preferably satisfy the relationships V1/V0 ⁇ 0.76 and V2/V0 ⁇ 0.94.
  • the cumulative pore volume V0 (cm 3 /g) is the cumulative pore volume (cm 3 /g) for pore diameters of 0.01 ⁇ m or more and 10 ⁇ m or less.
  • the cumulative pore volume V1 is the cumulative pore volume (cm 3 /g) for pore diameters of 0.1 ⁇ m or more and 10 ⁇ m or less.
  • the cumulative pore volume V2 is the cumulative pore volume (cm 3 / g) for pore diameters of 0.05 ⁇ m or more and 10 ⁇ m or less.
  • an AutoPore V series manufactured by Micromeritics is used for measuring the pore size distribution.
  • Electrode foil for low voltages has a thin chemical conversion coating, which makes it easier to prevent small-diameter pores from being blocked by the chemical conversion coating.
  • V1/V0 is more preferably 0.69 or less, and even more preferably 0.68 or less.
  • V2/V0 is more preferably 0.92 or less, and even more preferably 0.91 or less.
  • the metal foil thickness TA may be, for example, 90 ⁇ m or more, 100 ⁇ m or more, 105 ⁇ m or more, or 120 ⁇ m or more. Furthermore, the metal foil thickness TA may be 200 ⁇ m or less, 150 ⁇ m or less, or less than 125 ⁇ m. The thickness of the metal foil may be, for example, 100 ⁇ m or more and less than 125 ⁇ m.
  • the thickness T of the porous portion may be 25 ⁇ m or more and 90 ⁇ m or less, 35 ⁇ m or more and 80 ⁇ m or less, or 35 ⁇ m or more and less than 50 ⁇ m.
  • the thickness T of the porous portion can be increased within the above range while ensuring a sufficient thickness of the core portion.
  • the thickness of the core portion may be, for example, 20 ⁇ m or more, or 25 ⁇ m or more.
  • the thickness of the core portion may also be, for example, 28 ⁇ m or less.
  • the metal foil thickness TA is large (for example, 100 ⁇ m or more or 105 ⁇ m or more), the stress generated in the metal foil (surface layer) during winding will be large, and therefore, when the indentation depth H is within the above range, the effect of improving tensile strength will be significant.
  • the ratio of the thickness of the porous portion per side to the thickness of the core portion may be 1.5 or more, or 1.7 or more.
  • the ratio of the thickness of the porous portion per side to the thickness of the core portion may be 2.1 or less, or 2.0 or less.
  • the surface roughness Ra of the metal foil (roughness of the outer surface of the porous portion) is preferably 1.5 ⁇ m or less, more preferably 0.1 ⁇ m or more and 1.5 ⁇ m or less, and may be 0.5 ⁇ m or more and 1.5 ⁇ m or less.
  • the surface roughness Ra of the metal foil refers to the arithmetic mean roughness, and is determined in accordance with JIS B 0601:2001.
  • the surface roughness Ra of the metal foil is reduced to 1.5 ⁇ m or less by the compression process described below, the effects of rolling marks can be sufficiently reduced.
  • the surface roughness of the metal foil can be made smaller than the surface roughness due to the rolling marks of the original foil, and unnecessary oxides along the rolling marks can be removed. Furthermore, if the surface roughness Ra of the metal foil is 0.1 ⁇ m or more, the surface area of the metal foil is sufficiently secured, making it easier to increase the capacity.
  • the metal foil contains a valve metal.
  • valve metals include Al, Ta, and Nb.
  • the metal foil may be a foil of a valve metal (e.g., Al), or a foil containing an alloy or compound containing a valve metal (e.g., Al).
  • the dielectric layer is formed by anodization (chemical conversion treatment).
  • the dielectric layer is, for example, a layer containing an oxide of a valve metal (e.g., aluminum oxide).
  • the porous portion has an inner layer region on the core side and a surface layer region on the opposite side of the core.
  • the surface layer region is a region that is a distance of T/4 or less from the outer surface of the porous portion (the main surface of the metal foil that has the porous portion).
  • the inner layer region is a region that is a distance of T/4 or less from the boundary between the porous portion and the core.
  • the average diameter D1 of the pores in the surface region is preferably smaller than the average diameter D2 of the pores in the inner region. In this case, the retention of electrolyte within the pores in the porous portion is enhanced, improving contact between the dielectric layer and the electrolyte.
  • the compression process described below makes it easy to form a porous portion in which D1/D2 is less than 1. Note that, in this specification, the term “diameter” simply refers to "diameter.” D1/D2 is preferably 0.98 or less, and may be 0.95 or less, or 0.9 or less.
  • the ratio of D1 to D2 is preferably 0.5 or more, more preferably 0.55 or more, and may be 0.6 or more, or 0.7 or more.
  • the range of D1/D2 may be, for example, 0.5 or more and 0.98 or less, or 0.55 or more and 0.95 or less.
  • the porosity P1 of the surface layer region is smaller than the porosity P2 of the inner layer region.
  • P1/P2 may be 0.95 or less, 0.92 or less, or 0.85 or less.
  • the ratio of P1 to P2: P1/P2 is preferably 0.5 or more, more preferably 0.55 or more, and may be 0.6 or more, or 0.7 or more.
  • the range of P1/P2 may be, for example, 0.5 or more and 0.95 or less, or 0.55 or more and 0.92 or less.
  • the above average diameters D1 and D2 can be determined as follows.
  • (i) A cross-sectional image of the electrode foil is obtained using a scanning electron microscope (SEM). Using this image, the thickness of the porous portion is measured at any 10 points, and the average value is calculated to be the thickness T of the porous portion.
  • the surface region is defined as a region that is at a distance of T/4 or less from the outer surface of the porous portion (surface S1 in FIG. 1).
  • a cross-sectional image of the surface region is obtained, and the image is subjected to binarization processing to distinguish between the metal skeleton region that constitutes the surface region and the pore (pit) region other than the metal skeleton region.
  • a point in the pore region of the surface layer region is arbitrarily selected, a line segment passing through the selected point and crossing the pore region is drawn, and the length of the line segment at its shortest point is measured. This measurement is performed for 20 arbitrary points in the pore region of the surface layer region, and the average of the obtained measurements is calculated to be the average diameter D1 of the pores in the surface layer region.
  • the region of the porous portion at a distance of T/4 or less from the boundary with the core portion (surface B in FIG. 1) is defined as the inner layer region.
  • the average pore diameter D2 of the inner layer region is also determined in the same manner as in (iii) and (iv) above.
  • the porosity P1 can be determined by measuring the area S0 of the entire surface area after the binarization process in (iii) above, and the area S1 of the area occupied by pores in the image, and then calculating (S1/S0) x 100.
  • the porosity P2 can also be determined in the same manner.
  • the main surfaces of the electrode foil include a first main surface and a second main surface opposite the first main surface.
  • the porous portion may include, via a core portion, a first porous portion having a first main surface and a second porous portion having a second main surface.
  • the dielectric layer may include a first dielectric layer covering the first porous portion and a second dielectric layer covering the second porous portion. In this case, it is sufficient that at least one of the first indentation depth H1 and the second indentation depth H2 is within the above-mentioned range of indentation depth H. It is preferable that both the first indentation depth H1 and the second indentation depth H2 are within the above-mentioned range of indentation depth H.
  • the first indentation depth H1 may be smaller than the second indentation depth H2.
  • the anode foil is wound around the wound body so that the first main surface faces the outer periphery of the wound body. Since the tensile stress generated on the outer periphery of the wound body is greater during winding, making the first indentation depth H1 smaller than the second indentation depth H2 significantly reduces the occurrence of cracks during winding.
  • Figure 1 is a cross-sectional view schematically illustrating an example of an electrode foil according to one embodiment of the present disclosure.
  • Figure 1 shows a cross-section of the electrode foil in the thickness direction. Note that the electrode foil according to the present disclosure is not limited to this.
  • the electrode foil comprises a metal foil 300 having a porous portion on its main surface and a dielectric layer (not shown) covering the porous portion.
  • the metal foil 300 comprises a valve metal.
  • the main surfaces of the metal foil 300 include a first main surface S1 and a second main surface S2 opposite the first main surface S1.
  • the porous portion comprises a first porous portion 310 on the first main surface S1 and a second porous portion 320 on the second main surface S2.
  • the metal foil 300 comprises a core portion 330 and the first porous portion 310 and second porous portion 320 connected to the core portion 330.
  • the core portion 330 is formed between the first porous portion 310 and the second porous portion 320.
  • the dielectric layer comprises a first dielectric layer (not shown) covering the metal skeleton that constitutes the first porous portion 310 and a second dielectric layer (not shown) covering the metal skeleton that constitutes the second porous portion 320.
  • At least one of the first indentation depth H1 and the second indentation depth H2 is an indentation depth H within the above range.
  • the first indentation depth H1 is the indentation depth measured by nanoindentation when the maximum indentation load on the first main surface S1, which has the first porous portion 310 covered with the first dielectric layer, is 500 mN.
  • the second indentation depth H2 is the indentation depth measured by nanoindentation when the maximum indentation load on the second main surface S2, which has the second porous portion 320 covered with the second dielectric layer, is 500 mN. It is preferable that both the first indentation depth H1 and the second indentation depth H2 are indentation depths H within the above range.
  • the first indentation depth H1 may be approximately the same as the second indentation depth H2, or they may be different.
  • the porous portion 310 has a thickness T ( ⁇ m) and includes an inner layer region 312 on the core portion 330 side and a surface layer region 311 on the opposite side of the core portion 330.
  • the surface layer region 311 is a region that is a distance of T/4 or less from the outer surface S of the porous portion 310.
  • the inner layer region 312 is a region that is a distance of T/4 or less from the boundary B between the porous portion 310 and the core portion 330. The same can be said for the porous portion 320 (surface layer region 321 and inner layer region 322).
  • the manufacturing method of an electrode foil according to an embodiment of the present disclosure includes an etching step, a compression step, and a chemical conversion step.
  • etching step a sheet containing a valve metal is etched, thereby forming a porous portion on the main surface of the sheet.
  • compression step the etched sheet is compressed in the thickness direction to form a porous portion (a moderately compressed porous portion) on the main surface of the sheet.
  • chemical conversion step the compressed sheet is subjected to a chemical conversion treatment to form a dielectric layer covering the porous portion.
  • the indentation depth H is 17 ⁇ m or less.
  • electrode foil E2 the indentation depth H is 13.5 ⁇ m or less.
  • electrode foil E3 the indentation depth H is 10.5 ⁇ m or less.
  • the sheet used in the etching process contains a valve metal.
  • the valve metal include Al, Ta, and Nb.
  • the raw material sheet may be a sheet of a valve metal (e.g., Al), or may be a sheet containing an alloy or compound containing a valve metal (e.g., Al).
  • a long or strip-shaped rolled sheet (rolled foil) is usually used as the raw material sheet.
  • the surface of a sheet containing a valve metal is roughened by etching.
  • the etching process forms porous portions on the main surface of the sheet, leaving the remaining portion as a core.
  • the sheet has a core and a porous portion continuous with the core, and the porous portion occupies the main surface of the sheet.
  • the porous portions are usually formed on both main surfaces of the sheet, sandwiching the core.
  • the etching treatment may be electrolytic etching or chemical etching, and may be performed using a known technique.
  • the electrolytic etching may be performed at a current density of 2.0 A/ cm2 or less, 1.5 A/ cm2 or less, or 1.2 A/ cm2 or less.
  • the current density may be changed during etching.
  • AC etching is preferred, but DC etching is also acceptable.
  • AC etching makes it easier to form porous areas containing sponge-like pits with relatively small diameters.
  • DC etching makes it easier to form porous areas containing tunnel-like pits with relatively large diameters. Larger pit diameters in the porous areas make it easier to form thicker dielectric layers, which is advantageous in terms of higher voltages.
  • the temperature of the etching solution can be set to 10°C or higher and 60°C or lower between 0 and 0.7TE, and 5°C or higher and 40°C or lower between 0.7TE and TE. In this case, the variation in pit diameter in the thickness direction of the porous portion can be reduced.
  • the etching time TE is, for example, 15 minutes or higher and 30 minutes or lower.
  • the etched sheet is compressed.
  • the etched sheet may be compressed by conveying it between a pair of rollers.
  • the porous portion (particularly the surface layer) formed by the etching process has low strength and is easily compressed in the compression process.
  • the thickness of the porous portion (particularly the surface layer) is reduced by compression.
  • the thickness of the core portion may be slightly reduced before and after compression, but it is desirable that it remains almost the same.
  • the sheet comes into contact with processing liquids (e.g., etching liquid, chemical conversion liquid) and rollers, which can cause unevenness (or scratches).
  • processing liquids e.g., etching liquid, chemical conversion liquid
  • rollers which can cause unevenness (or scratches).
  • stress can concentrate on these unevenness, causing the sheet to break (or crack).
  • the aluminum foil used in the sheet has rolling marks created during the manufacturing process, and etching pits can form unevenly along the rolling marks, i.e., along the length of the long sheet (rolling direction). The rolling marks can cause the sheet to break (or crack).
  • the thickness TA of the compressed sheet may be 90 ⁇ m or more and 200 ⁇ m or less, or 120 ⁇ m or more and 200 ⁇ m or less.
  • the thickness T of the porous portion per side after compression may be 25 ⁇ m or more and ⁇ (TA/2)-10 ⁇ ⁇ m or less. If the thickness T is within the above range, the core portion can be sufficiently thick. Furthermore, the thickness T may be 25 ⁇ m or more and 90 ⁇ m or less, or 35 ⁇ m or more (or 40 ⁇ m or more) and 80 ⁇ m or less. In high-capacity foils, the thickness T of the porous portion is large, and the effect of improving the surface strength through compression is significantly achieved.
  • high-capacity foils are used in capacitors containing solid electrolytes and liquid components (such as electrolytic solutions), and the thickness TA of the sheet (electrode foil) is preferably 100 ⁇ m or more (or 105 ⁇ m or more) or 120 ⁇ m or more, and the thickness T of the porous portion per side is preferably 25 ⁇ m or more or 35 ⁇ m or more (or 40 ⁇ m or more).
  • the compression rate (thickness reduction rate) of the porous portion during the compression process may be 5% or more and 40% or less, or 9% or more and 30% or less, or 14% or more and 25% or less.
  • the thickness reduction rate of the porous portion is calculated by ((T0 - T)/T0) x 100, where T is the thickness per side of the porous portion after compression, and T0 is the thickness per side of the porous portion before compression. Compression may be performed so that the thickness of the core portion remains almost unchanged before and after compression.
  • the compressed sheet is subjected to a chemical conversion treatment to form a dielectric layer (chemical conversion film) that covers the porous portion.
  • the chemical conversion treatment forms an aluminum oxide layer as a chemical conversion film.
  • the chemical conversion voltage and other parameters can be adjusted according to the withstand voltage (rated voltage of the electrolytic capacitor) to form a chemical conversion film of a predetermined thickness.
  • the withstand voltage can be approximately the same as the chemical conversion voltage or slightly lower than the chemical conversion voltage.
  • An electrolytic capacitor according to an embodiment of the present disclosure includes a wound capacitor element, and the wound capacitor element includes a winding body and an electrolyte.
  • the winding body is configured by winding an anode foil, a cathode foil, and a separator disposed between the anode foil and the cathode foil.
  • the anode foil is an electrode foil according to an embodiment of the present disclosure. Because the electrode foil according to the present disclosure has high strength, the occurrence of cracks or foil tears in the electrode foil included in the winding body is suppressed.
  • electrolytic capacitors with a rated voltage of 20 V or higher aluminum foil that has been chemically treated at a chemical voltage of 30 V or higher is often used as the anode foil.
  • aluminum foil that has been chemically treated at a chemical voltage of 40 V or higher is often used as the anode foil.
  • an electrode foil with a relatively large pit diameter is used, forming a dielectric layer with a relatively large thickness (for example, a thickness of 45 nm or higher), which tends to reduce the strength of the surface layer. Therefore, by using an electrode foil according to an embodiment of the present disclosure, a significant improvement in reliability can be achieved.
  • the resulting chemical conversion film becomes thick. Therefore, by using an electrode foil with a large pit diameter, pit blockage by a thick chemical conversion film is suppressed, allowing for efficient capacity enhancement.
  • the cathode foil may be a metal foil containing a valve metal such as Al, Ta, or Nb. If necessary, the surface of the metal foil may be roughened by etching. That is, the cathode foil may be a metal foil having a porous portion and a core portion continuous with the porous portion.
  • the electrode foil according to the present disclosure or a compressed, unformed, etched foil obtained during the manufacturing process of the electrode foil according to the present disclosure may be used as the cathode foil.
  • the thickness of the cathode foil is, for example, 70 ⁇ m or more and 100 ⁇ m or less.
  • the electrolyte covers at least a portion of the anode foil (dielectric layer) and is interposed between the anode foil (dielectric layer) and the cathode foil.
  • the electrolyte includes at least one of a solid electrolyte and an electrolytic solution.
  • the capacitor element may include a solid electrolyte, or may include a solid electrolyte and a liquid component (electrolytic solution or a non-aqueous solvent).
  • the dielectric layer is coated with an electrolyte by, for example, impregnating the anode foil (or wound body) with a treatment solution (or electrolyte solution) containing a conductive polymer.
  • a treatment solution or electrolyte solution
  • D1 is smaller than D2 (and P1 is smaller than P2), so the treatment solution impregnated in the porous portion tends to remain within the pores, and the inner walls of the pores are easily covered with electrolyte, improving contact between the anode foil (dielectric layer) and the electrolyte.
  • the solid electrolyte includes a conductive polymer.
  • conductive polymers include ⁇ -conjugated polymers.
  • conductive polymers include polypyrrole, polythiophene, polyfuran, and polyaniline.
  • One type of conductive polymer may be used alone, two or more types may be used in combination, or a copolymer of two or more types of monomers may be used.
  • the weight-average molecular weight of the conductive polymer is, for example, 1,000 to 100,000.
  • the conductive polymer may be doped with a dopant.
  • the solid electrolyte may contain a dopant along with the conductive polymer. Examples of dopants include polystyrene sulfonic acid.
  • the solid electrolyte may further contain additives as needed.
  • a high-boiling point solvent is preferred as the non-aqueous solvent.
  • polyol compounds such as ethylene glycol, sulfone compounds such as sulfolane, lactone compounds such as ⁇ -butyrolactone, ester compounds such as methyl acetate, carbonate compounds such as propylene carbonate, ether compounds such as 1,4-dioxane, and ketone compounds such as methyl ethyl ketone can be used.
  • the liquid component may contain an acid component (anion) and a base component (cation).
  • the acid component and base component may form a salt (solute).
  • the acid component contributes to the film repair function.
  • acid components include organic carboxylic acids and inorganic acids.
  • inorganic acids include phosphoric acid, boric acid, and sulfuric acid.
  • base components include primary to tertiary amine compounds.
  • An organic salt is a salt in which at least one of the anion and cation contains an organic substance.
  • organic salts include trimethylamine maleate, triethylamine borodisalicylate, ethyldimethylamine phthalate, mono-1,2,3,4-tetramethylimidazolinium phthalate, and mono-1,3-dimethyl-2-ethylimidazolinium phthalate.
  • the liquid component contains more acid components than base components. Furthermore, since the acid components contribute to the film repair function of the liquid component, it is also preferable that the liquid component contain more acid components than base components.
  • the molar ratio of the acid components to the base components is, for example, 1.1 or more.
  • the pH of the liquid component may be 6 or less, or may be 1 or more and 5 or less.
  • Figure 2 is a cross-sectional view schematically illustrating an example of an electrolytic capacitor according to one embodiment of the present disclosure.
  • Figure 3 is a perspective view schematically illustrating the configuration of the wound body of Figure 2.
  • the electrolytic capacitor 200 comprises a capacitor element, which comprises a wound body 100 and an electrolyte (not shown).
  • the wound body 100 is formed by winding an anode foil 10 and a cathode foil 20 with a separator 30 interposed therebetween.
  • lead tabs 50A and 50B One end of lead tabs 50A and 50B is connected to the anode foil 10 and the cathode foil 20, respectively, and the wound body 100 is formed by winding the lead tabs 50A and 50B.
  • Lead wires 60A and 60B are connected to the other ends of the lead tabs 50A and 50B, respectively.
  • a stop tape 40 is placed on the outer surface of the cathode foil 20, which is located in the outermost layer of the wound body 100, and the ends of the cathode foil 20 are fixed by the stop tape 40.
  • the wound body 100 may be further subjected to a chemical conversion treatment to provide a dielectric layer on the cut surface.
  • An electrolyte is interposed between the anode foil 10 (dielectric layer) and the cathode foil 20 in the wound body 100.
  • the capacitor element is obtained, for example, by impregnating the wound body 100 with a treatment liquid containing an electrolyte. Impregnation may be performed under reduced pressure, for example, in an atmosphere of 10 kPa to 100 kPa.
  • the wound body 100 is housed in the bottomed case 211 so that the lead wires 60A and 60B are located on the open side of the bottomed case 211.
  • the bottomed case 211 can be made of metals such as aluminum, stainless steel, copper, iron, brass, or alloys of these.
  • a sealing member 212 is placed at the opening of the bottomed case 211, which contains the wound body 100 and electrolyte, and the open end of the bottomed case 211 is crimped to the sealing member 212 and curled.
  • a seat plate 213 is placed on the curled portion, sealing the wound body 100 within the bottomed case 211.
  • Sealing member 212 is formed so that lead wires 60A and 60B can pass through it. Any insulating material will do for sealing member 212, and an elastic material is preferable. Among these, highly heat-resistant materials such as silicone rubber, fluororubber, ethylene propylene rubber, hypalon rubber, butyl rubber, and isoprene rubber are preferred.
  • One or more laminated capacitor elements may be used. Multiple laminated capacitor elements may be stacked to form a laminate. Stress is likely to occur in the anode bodies (the connection sides with the anode leads) located at both ends of the laminate, but the electrode foil disclosed herein has high strength, which prevents cracks from occurring due to such stress.
  • the anode body is produced, for example, by cutting (or punching) a large sheet into a desired shape after chemical conversion treatment. Because the sheet that has undergone the etching, compression, and chemical conversion processes of the present disclosure has high strength, the occurrence of cracks and defects due to cutting, etc. is suppressed.
  • the above description of the embodiments discloses the following techniques.
  • (Technology 1) An electrode foil having a withstand voltage of 7 V or less, The electrode foil includes a metal foil having a porous portion on a main surface thereof and a dielectric layer covering the porous portion, the metal foil comprises a valve metal; An electrode foil, wherein an indentation depth H measured by a nanoindentation method when a maximum indentation load is 500 mN on the main surface having the porous portion covered with the dielectric layer is 17 ⁇ m or less.
  • (Technology 2) 2. The electrode foil according to claim 1, wherein the dielectric layer is a chemical conversion coating.
  • (Technology 3) The electrode foil according to Art.
  • (Technology 9) 9.
  • (Technology 10) 10.
  • the electrode foil according to any one of claims 6 to 9, wherein the elastic modulus measured by a nanoindentation method when a maximum indentation load on the main surface having the porous portion covered with the dielectric layer is 9000 mN/ mm2 or more.
  • the electrode foil having a withstand voltage of more than 22 V and not more than 160 V,
  • the electrode foil includes a metal foil having a porous portion on a main surface thereof and a dielectric layer covering the porous portion, the metal foil comprises a valve metal;
  • Technology 13 13.
  • (Technology 14) 14 14.
  • (Technology 15) 15 15.
  • the electrode foil according to any one of claims 11 to 14, wherein the elastic modulus measured by a nanoindentation method when a maximum indentation load on the main surface having the porous portion covered with the dielectric layer is 15,000 mN/ mm2 or more.
  • an integrated pore volume V0 (cm 3 /g) of pores with a diameter of 0.01 ⁇ m or more and 10 ⁇ m or less; an integrated pore volume V1 (cm 3 /g) of pores with a diameter of 0.1 ⁇ m or more and 10 ⁇ m or less;
  • the cumulative pore volume V2 (cm 3 /g) of pores with a diameter of 0.05 ⁇ m or more and 10 ⁇ m or less means: V1/V0 ⁇ 0.76 and V2/V0 ⁇ 0.94 16.
  • the electrode foil according to any one of techniques 1 to 15, which satisfies the following relationship: (Technology 17) 17.
  • the anode foil is an electrode foil according to any one of techniques 1 to 18.
  • the main surfaces of the metal foil of the anode foil include a first main surface and a second main surface opposite to the first main surface, the porous portion includes a first porous portion on the first main surface and a second porous portion on the second main surface;
  • the dielectric layer includes a first dielectric layer covering the first porous portion and a second dielectric layer covering the second porous portion;
  • a first indentation depth H1 measured by a nanoindentation method when a maximum indentation load is 500 mN on the first main surface having the first porous portion covered with the first dielectric layer is smaller than a second indentation depth H2 measured by a nanoindentation method when a maximum indentation load is 500 mN on the second main surface having the second porous portion covered with the second dielectric layer;
  • At least the first indentation depth H1 is the indentation depth H, 20.
  • Technology 21 A method for manufacturing an electrode foil having a withstand voltage of 7 V or less, an etching step of etching a sheet including a valve metal; a compressing step of compressing the etched sheet in a thickness direction to form a porous portion on a main surface of the sheet; and performing a chemical conversion treatment on the compressed sheet to form a dielectric layer covering the porous portion, a nanoindentation depth H of 17 ⁇ m or less when a maximum indentation load of 500 mN is applied to the main surface having the porous portion covered with the dielectric layer, as measured by a nanoindentation method.
  • an integrated pore volume V0 (cm 3 /g) of pores with a diameter of 0.01 ⁇ m or more and 10 ⁇ m or less; an integrated pore volume V1 (cm 3 /g) of pores with a diameter of 0.1 ⁇ m or more and 10 ⁇ m or less;
  • the cumulative pore volume V2 (cm 3 /g) of pores with a diameter of 0.05 ⁇ m or more and 10 ⁇ m or less means: V1/V0 ⁇ 0.76 and V2/V0 ⁇ 0.94
  • a metal foil (thickness TB: 125 ⁇ m) was etched to obtain a metal foil (etched foil) having a core and a porous portion. Al foil was used as the metal foil. Porous portions (thickness per side T0: 50 ⁇ m) were formed on both sides of the metal foil, and the thickness of the core was 25 ⁇ m.
  • the etching was performed using AC etching, with the current density appropriately adjusted within a range of 1.5 A/ cm2 or less. The etching time was also appropriately adjusted to achieve the desired dissolution amount.
  • Electrode foils a1 to a4 were subjected to a chemical conversion treatment to form a dielectric layer covering the porous portion.
  • the chemical conversion treatment and withstand voltage measurement were performed in accordance with the Electronic Industries Association of Japan (EIAJ) RC-2364A standard test method for electrode foils for aluminum electrolytic capacitors.
  • the chemical conversion voltage was 5 V, 20 V, or 70 V.
  • electrode foils A1 to A4 electrode foil E1, chemical conversion voltage 5 V
  • electrode foils A11 to A14 electrode foils A11 to A14 (electrode foil E2, chemical conversion voltage 20 V)
  • electrode foils A21 to A24 electrode foil E3, chemical conversion voltage 70 V
  • the withstand voltage was approximately the same as or slightly lower than the chemical conversion voltage.
  • the indentation depth H, hardness X, elastic modulus Y were determined by the methods described above. Note that in each table, the indentation depth H and other values are shown as measured values for one main surface of the electrode foil, but almost the same measured values were also obtained for the other main surface of the electrode foil.
  • tensile strength For each metal foil before chemical conversion treatment, a strip-shaped sample (70 mm in length, 10 mm in width) was prepared, and the tensile strength of the sample in the length direction was measured in accordance with the test method for electrode foil for aluminum electrolytic capacitors (EIAJ RC-2364A) of the Electronic Industries Association of Japan standard. The measurement results are shown in Table 1. In Table 1, the tensile strength is shown as a relative value when the tensile strength of metal foil b1 is set to 100.
  • the electrostatic capacitance per unit thickness of the electrode foil was measured in accordance with the test method for electrode foil for aluminum electrolytic capacitors of the Electronic Industry Standards of Japan (EIAJ RC-2364A).
  • the capacitance/thickness indicates a relative value when the capacitance/thickness of anode foil B1 is set to 100.
  • the capacitance/thickness indicates a relative value when the capacitance/thickness of anode foil B11 is set to 100.
  • the capacitance/thickness indicates a relative value when the capacitance/thickness of anode foil B21 is set to 100.
  • Metal foils a1 to a4 had a higher tensile strength than metal foil b1. Electrode foils A1 to A4 had a higher (capacity/thickness) than electrode foil B1. Electrode foils A11 to A14 had a higher (capacity/thickness) than electrode foil B11. Electrode foils A21 to A24 had a higher (capacity/thickness) than electrode foil B21.
  • Electrode foils A1 to A4 had a smaller indentation depth H and a greater hardness X and elastic modulus Y than electrode foil B1, resulting in higher tensile strength.
  • Electrode foils A11 to A14 had a smaller indentation depth H and a greater hardness X and elastic modulus Y than electrode foil B11, resulting in higher tensile strength.
  • Electrode foils A21 to A24 had a smaller indentation depth H and a greater hardness X and elastic modulus Y than electrode foil B21, resulting in higher tensile strength.
  • a metal foil (thickness TB: 125 ⁇ m) was subjected to an etching process to obtain a metal foil (etched foil) having a core portion and a porous portion. Al foil was used as the metal foil. Porous portions (thickness per side T0: 51 ⁇ m) were formed on both sides of the metal foil, and the thickness of the core portion was set to 23 ⁇ m.
  • the etching process involved AC etching, with the current density appropriately adjusted within a range of 1.5 A/ cm2 or less. The etching time was also appropriately adjusted to obtain the desired dissolution amount.
  • the metal foils a5 to a8 were subjected to chemical conversion treatment to form a dielectric layer covering the porous portion.
  • the chemical conversion treatment and measurement of the withstand voltage were carried out in the same manner as described above.
  • the chemical conversion voltage was 5 V, 20 V, or 70 V.
  • electrode foils A5 to A8 electrode foil E1, chemical conversion voltage 5 V
  • electrode foils A15 to A18 electrode foils A2, chemical conversion voltage 20 V
  • electrode foils A25 to A28 electrode foil E3, chemical conversion voltage 70 V
  • the withstand voltage was approximately the same as the chemical conversion voltage or slightly lower than the chemical conversion voltage.
  • Electrode foil B2, B12, B22 The etched metal foil was prepared as metal foil b2 without being compressed. Electrode foils B2, B12, and B22 were prepared in the same manner as electrode foils A5, A15, and A25, except that metal foil b2 was used instead of metal foil a5.
  • the indentation depth H, hardness X, elastic modulus Y were determined by the methods described above. Note that in each table, the indentation depth H and other values are shown as measured values for one main surface of the electrode foil, but almost the same measured values were also obtained for the other main surface of the electrode foil.
  • V1/V0, V2/V0 V1/V0, V2/V0
  • V1/V0 and V2/V0 V1/V0 and V2/V0 of the porous portion of each metal foil before chemical conversion treatment were determined.
  • V1/V0 was within a range of 0.76 or less
  • V2/V0 was within a range of 0.94 or less.
  • V1/V0 was greater than 0.76
  • V2/V0 was greater than 0.94. Note that V1/V0 and V2/V0 indicate values measured on one main surface of the metal foil, but approximately similar values were also obtained for the other main surface of the metal foil.
  • Capacity/Thickness For each electrode foil, the capacitance per unit thickness of the electrode foil (capacitance/thickness) was measured in the same manner as above.
  • the capacitance/thickness indicates a relative value when the capacitance/thickness of anode foil B2 is set to 100.
  • the capacitance/thickness indicates a relative value when the capacitance/thickness of anode foil B12 is set to 100.
  • the capacitance/thickness indicates a relative value when the capacitance/thickness of anode foil B22 is set to 100.
  • Metal foils a5 to a8 had a higher tensile strength than metal foil b2. Electrode foils A5 to A8 had a higher (capacity/thickness) than electrode foil B2. Electrode foils A15 to A18 had a higher (capacity/thickness) than electrode foil B12. Electrode foils A25 to A28 had a higher (capacity/thickness) than electrode foil B22.
  • Electrode foils A5 to A8 had a smaller indentation depth H and a greater hardness X and elastic modulus Y than electrode foil B2, resulting in higher tensile strength.
  • Electrode foils A15 to A18 had a smaller indentation depth H and a greater hardness X and elastic modulus Y than electrode foil B12, resulting in higher tensile strength.
  • Electrode foils A25 to A28 had a smaller indentation depth H and a greater hardness X and elastic modulus Y than electrode foil B22, resulting in higher tensile strength.
  • the electrode foil disclosed herein is suitable for use in electrolytic capacitors that require high reliability.

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  • Engineering & Computer Science (AREA)
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  • Electrolytic Production Of Metals (AREA)

Abstract

L'invention concerne une feuille d'électrode pour condensateurs électrolytiques qui comprend une feuille métallique qui a une partie poreuse sur une surface principale de celle-ci et une couche diélectrique qui recouvre la partie poreuse. La feuille métallique contient un métal d'action de soupape. Lorsque la feuille d'électrode a une tension de tenue inférieure ou égale à 7 V, la profondeur d'indentation H n'est pas supérieure à 17 µm. Lorsque la tension de tenue de la feuille d'électrode est supérieure à 7 V mais inférieure ou égale à 22 V, la profondeur d'indentation H n'est pas supérieure à 13,5 µm. Lorsque la tension de tenue de la feuille d'électrode est supérieure à 22 V mais inférieure ou égale à 160 V, la profondeur d'indentation H n'est pas supérieure à 10,5 µm.
PCT/JP2025/026708 2024-07-30 2025-07-28 Feuille d'électrode, condensateur électrolytique et procédé de production de feuille d'électrode Pending WO2026029005A1 (fr)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015155564A (ja) * 2014-02-20 2015-08-27 日立金属株式会社 電解アルミニウム箔、蓄電デバイス用集電体、蓄電デバイス用電極、蓄電デバイス
WO2024162155A1 (fr) * 2023-01-30 2024-08-08 パナソニックＩｐマネジメント株式会社 Feuille d'électrode pour condensateurs électrolytiques, condensateur électrolytique et procédé de fabrication d'une feuille d'électrode pour condensateurs électrolytiques

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015155564A (ja) * 2014-02-20 2015-08-27 日立金属株式会社 電解アルミニウム箔、蓄電デバイス用集電体、蓄電デバイス用電極、蓄電デバイス
WO2024162155A1 (fr) * 2023-01-30 2024-08-08 パナソニックＩｐマネジメント株式会社 Feuille d'électrode pour condensateurs électrolytiques, condensateur électrolytique et procédé de fabrication d'une feuille d'électrode pour condensateurs électrolytiques

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