Electrode material for aluminum electrolytic capacitors and method for producing same
The present invention provides an electrode material for aluminum electrolytic capacitors, the electrode material being capable of exhibiting a high capacitance required for capacitors and having suppressed equivalent series resistance (ESR), and provides a method for producing the electrode material. The present invention provides an electrode material for aluminum electrolytic capacitors, comprising a sintered body of an aluminum alloy powder on at least one surface of a substrate, wherein the substrate is an aluminum foil substrate or an aluminum alloy foil substrate, and the aluminum alloy powder contains Fe in an amount of 2 to 499 mass ppm.
1 . An electrode material for aluminum electrolytic capacitors, comprising a sintered body of an aluminum alloy powder on at least one surface of a substrate, wherein
the substrate is an aluminum foil substrate or an aluminum alloy foil substrate,
the aluminum alloy powder contains Fe in an amount of 100 to 499 mass ppm, and
a porosity of the electrode material is 46% or more.
2 . The electrode material for aluminum electrolytic capacitors according to claim 1 , wherein the aluminum alloy powder contains Fe in an amount of 100 to 400 mass ppm, and the remainder comprises Al and an unavoidable impurity.
3 . The electrode material for aluminum electrolytic capacitors according to claim 1 , wherein the aluminum alloy powder has an average particle diameter D 50 of 1.5 μm or more and 15 μm or less.
4 . The electrode material for aluminum electrolytic capacitors according to claim 1 , wherein the substrate is an aluminum foil substrate having an Al purity of 99.99 mass % or more, and has a thickness of 10 μm or more and 80 μm or less.
5 . The electrode material for aluminum electrolytic capacitors according to claim 1 , wherein the sintered body is formed on both surfaces of the substrate, and has a total thickness of 50 μm or more and 2000 μm or less.
6 . A method for producing an electrode material for aluminum electrolytic capacitors, comprising
(1) step 1 of forming a film of a paste composition containing an aluminum alloy powder on at least one surface of a substrate, and
(2) step 2 of sintering the film at a temperature of 560° C. or more and 660° C. or less,
wherein
the substrate is an aluminum foil substrate or an aluminum alloy foil substrate,
the aluminum alloy powder contains Fe in an amount of 100 to 499 mass ppm, and
a porosity of the electrode material is 46% or more.
7 . The production method according to claim 6 , wherein the aluminum alloy powder has an average particle diameter D 50 of 1.5 μm or more and 15 μm or less.
8 . The production method according to claim 6 , further comprising an anodization step after step 2, wherein the voltage in the anodization step is 250 V or more and 800 V or less.