Method for detecting foil ash on surface of aluminum electrode foil

Abstract

The invention relates to the technical field of aluminum foils for capacitors, in particular to a method for detecting foil ash on the surface of an aluminum electrode foil. The method for detecting the foil ash on the surface of the aluminum electrode foil comprises the following steps: preparing a sample, weighing, preparing a solution, treating and calculating weightlessness, soaking the aluminum electrode foil by adopting a mixed solution obtained by dissolving aluminum in a dilute sulfuric acid solution, cleaning the foil ash on the surface, and finally measuring the amount of the foil ash on the surface of the aluminum foil by the weightlessness. The method is simple and convenient, is high in accuracy, can quickly screen out unqualified foil grey products, improves the product quality, is high in accuracy compared with the traditional judgment depending on experience, and has a great influence on the detection of the bright aluminum foil.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum foil for capacitors, and in particular to a method for detecting foil dust on the surface of aluminum electrode foil. Background Art

[0002] The anode foil for aluminum electrolytic capacitors uses the method of electrochemical corrosion expansion to obtain high specific capacitance. With the demand for miniaturization and lightweight in the electronics market, the capacity requirements of aluminum electrolytic capacitors are getting higher and higher. Correspondingly, the corrosion amount of the anode foil is also increasing, which can easily cause over-corrosion, resulting in serious powder loss on the surface of the electrode foil, causing inconvenience to the production of the electrode foil, and the manufactured capacitors are prone to problems such as large contact resistance and short circuit. Therefore, the electrode foil must control the foil ash within a certain range, but there is currently no method to quantitatively determine the foil ash. The common method is to wear white gloves, wipe the foil surface, and see how much foil ash is left on the gloves to determine whether the electrode foil is usable. This method relies entirely on experience and has low accuracy. Summary of the invention

[0003] In view of this, the purpose of the present invention is to propose a method for detecting foil dust on the surface of aluminum electrode foil, so as to provide a method for quantitatively determining the amount of foil dust on the surface of aluminum electrode foil.

[0004] Based on the above purpose, the present invention provides a method for detecting foil dust on the surface of aluminum electrode foil, and the specific operation steps are as follows: S1: Cut the aluminum foil into squares for later use; S2: weigh the sample obtained in S1, which is m1; S3: Place the shredded aluminum foil in sulfuric acid solution, and heat to 60-65°C after it is fully dissolved; S4: Place the sample obtained in S1 into the solution obtained in S3, soak, dry, and weigh, which is m2; S5: Calculate the weight loss rate of the aluminum electrode foil according to the formula; The formula in step S5 is as follows: Weight loss rate .

[0005] Furthermore, the size of the square in step S1 is 50×50 mm.

[0006] Furthermore, the weighing in step S2 is performed using an electronic balance.

[0007] Furthermore, the concentration of the sulfuric acid solution in step S3 is 0.1-1.0 mol / L.

[0008] Furthermore, the amount of the shredded aluminum foil added in step S3 is such that the aluminum content in the sulfuric acid solution reaches 0.1-2 mol / L.

[0009] Furthermore, the soaking time in step S4 is 0.5-3 min.

[0010] Furthermore, when the sample to be immersed in step S4 is a corrosion foil, the immersion time is 0.5-2 minutes; when the sample to be immersed in step S4 is a chemical foil, the immersion time is 1-3 minutes.

[0011] The beneficial effects of the present invention are as follows: the method for detecting foil ash on the surface of aluminum electrode foil of the present invention is simple and easy to operate, with high accuracy, and can detect unqualified electrode foil with much foil ash in advance, thereby improving the yield rate of aluminum electrolytic capacitors. In addition, a part of the aluminum foil is first dissolved in a sulfuric acid solution innovatively, and then the sample is processed, which can not only effectively detect the amount of foil ash on the surface of the aluminum electrode foil, but also reduce the damage of sulfuric acid to the surface of the aluminum electrode foil. Compared with the traditional method of wearing white gloves, wiping the surface of the aluminum foil, and judging by how much foil ash is left on the gloves, the accuracy is greatly improved, and the method can be applied to the routine detection of foil ash on the electrode foil in industrial production. DETAILED DESCRIPTION

[0012] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0013] Embodiment 1: A method for detecting foil dust on the surface of aluminum electrode foil, the specific operation steps are as follows: (1) Sample preparation: Take the corrosion foil and cut a 50×50 mm sample from the corrosion foil; (2) Weighing: Use an electronic balance to weigh the sample, which is recorded as 0.0878 g; (3) Solution preparation: dilute sulfuric acid to 0.1 mol / L with deionized water, add chopped aluminum foil to make the aluminum content in the sulfuric acid solution reach 0.1 mol / L, wait for it to be completely dissolved, and heat it in a water bath to 60°C for later use; (4) Treatment: Soak the sample in the sulfuric acid solution obtained in step (3) for 0.5 min, take it out and rinse it with deionized water, dry it in a 60°C oven, and weigh it again, recording the weight as 0.0876 g; (5) Calculate weight loss: Weight loss rate according to the formula .

[0014] Embodiment 2: A method for detecting foil dust on the surface of aluminum electrode foil, the specific operation steps are as follows: (1) Sample preparation: Take the corrosion foil and cut a 50×50 mm sample from the corrosion foil; (2) Weighing: Use an electronic balance to weigh the sample, which is recorded as 0.0884 g; (3) Solution preparation: dilute sulfuric acid to 0.5 mol / L with deionized water, add chopped aluminum foil to make the aluminum content in the sulfuric acid solution reach 1 mol / L, wait for it to be completely dissolved, and heat it in a water bath to 60°C for later use; (4) Treatment: Soak the sample in the sulfuric acid solution obtained in step (3) for 1 min, take it out and rinse it with deionized water, dry it in an oven at 60°C, and weigh it again, recording the weight as 0.0882 g; (5) Calculate weight loss: Weight loss rate according to the formula .

[0015] Embodiment 3: A method for detecting foil dust on the surface of aluminum electrode foil, the specific operation steps are as follows: (1) Sample preparation: Take the corrosion foil and cut a 50×50 mm sample from the corrosion foil; (2) Weighing: Use an electronic balance to weigh the sample, which is recorded as 0.0875 g; (3) Solution preparation: dilute sulfuric acid to 1 mol / L with deionized water, add chopped aluminum foil to make the aluminum content in the sulfuric acid solution reach 2 mol / L, wait for it to be completely dissolved, and heat it in a water bath to 60°C for later use; (4) Treatment: Soak the sample in the sulfuric acid solution obtained in step (3) for 2 min, take it out and rinse it with deionized water, dry it in an oven at 60°C, and weigh it again, recording the weight as 0.0872 g; (5) Calculate weight loss: Weight loss rate according to the formula .

[0016] Embodiment 4: A method for detecting foil dust on the surface of aluminum electrode foil, the specific operation steps are as follows: (1) Sample preparation: Take the chemically formed foil and cut a 50×50 mm sample from the etched foil; (2) Weighing: Use an electronic balance to weigh the sample, which is recorded as 0.0934 g; (3) Solution preparation: dilute sulfuric acid to 0.1 mol / L with deionized water, add chopped aluminum foil to make the aluminum content in the sulfuric acid solution reach 0.1 mol / L, wait for it to be completely dissolved, and heat it in a water bath to 60°C for later use; (4) Treatment: Soak the sample in the sulfuric acid solution obtained in step (3) for 1 min, take it out and rinse it with deionized water, dry it in an oven at 60°C, and weigh it again, recording the weight as 0.0932 g; (5) Calculate weight loss: Weight loss rate according to the formula .

[0017] Embodiment 5: A method for detecting foil dust on the surface of aluminum electrode foil, the specific operation steps are as follows: (1) Sample preparation: Take the chemically formed foil and cut a 50×50 mm sample from the etched foil; (2) Weighing: Use an electronic balance to weigh the sample, which is recorded as 0.0947 g; (3) Solution preparation: dilute sulfuric acid to 0.5 mol / L with deionized water, add chopped aluminum foil to make the aluminum content in the sulfuric acid solution reach 1 mol / L, wait for it to be completely dissolved, and heat it in a water bath to 60°C for later use; (4) Treatment: Soak the sample in the sulfuric acid solution obtained in step (3) for 2 min, take it out and rinse it with deionized water, dry it in an oven at 60°C, and weigh it again, recording the weight as 0.0944 g; (5) Calculate weight loss: Weight loss rate according to the formula .

[0018] Embodiment 6: A method for detecting foil dust on the surface of aluminum electrode foil, the specific operation steps are as follows: (1) Sample preparation: Take the chemically formed foil and cut a 50×50 mm sample from the etched foil; (2) Weighing: Use an electronic balance to weigh the sample, which is recorded as 0.0953 g; (3) Solution preparation: dilute sulfuric acid to 1 mol / L with deionized water, add chopped aluminum foil to make the aluminum content in the sulfuric acid solution reach 2 mol / L, wait for it to be completely dissolved, and heat it in a water bath to 60°C for later use; (4) Treatment: Soak the sample in the sulfuric acid solution obtained in step (3) for 3 min, take it out and rinse it with deionized water, dry it in an oven at 60°C, and weigh it again, recording the weight as 0.095 g; (5) Calculate weight loss: Weight loss rate according to the formula .

[0019] Comparative Example: A method for detecting foil ash on the surface of aluminum electrode foil, which is different from Example 2 in that shredded aluminum foil is dissolved in a disaster-proof sulfuric acid solution, and the specific operating steps are as follows: (1) Sample preparation: Take the corrosion foil and cut a 50×50 mm sample from the corrosion foil; (2) Weighing: Use an electronic balance to weigh the sample, which is recorded as 0.0884 g; (3) Solution preparation: dilute sulfuric acid to 0.5 mol / L with deionized water and heat to 60°C in a water bath for later use; (4) Treatment: Soak the sample in the sulfuric acid solution obtained in step (3) for 1 min, take it out and rinse it with deionized water, dry it in an oven at 60°C, and weigh it again, recording the weight as 0.0873 g; (5) Calculate weight loss: Weight loss rate according to the formula .

[0020] In summary, the method for detecting foil ash on the surface of aluminum electrode foil of the present invention is simple and easy to operate, with high accuracy, and can detect unqualified electrode foil with a lot of foil ash in advance, thereby improving the yield rate of aluminum electrolytic capacitors. In addition, a part of the aluminum foil is innovatively dissolved in a sulfuric acid solution before processing the sample, which can not only effectively detect the amount of foil ash on the surface of the aluminum electrode foil, but also reduce the damage of sulfuric acid to the surface of the aluminum electrode foil, thereby further improving its accuracy.

[0021] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not mentioned in detail for the sake of simplicity.

Claims

1. A method for detecting foil dust on the surface of aluminum electrode foil, characterized in that: The specific steps are as follows: S1: Cut the aluminum foil into squares for later use; S2: weigh the sample obtained in S1, which is m1; S3: Place the shredded aluminum foil in sulfuric acid solution, and heat to 60-65°C after it is fully dissolved; S4: Place the sample obtained in S1 into the solution obtained in S3, soak, dry, and weigh, which is m2; S5: Calculate the weight loss rate of the aluminum electrode foil according to the formula; The formula in step S5 is as follows: 。 2. The method for detecting foil dust on the surface of aluminum electrode foil according to claim 1, characterized in that: The size of the square in step S1 is 50×50 mm.

3. The method for detecting foil dust on the surface of aluminum electrode foil according to claim 1, characterized in that: The weighing in step S2 is performed using an electronic balance.

4. The method for detecting foil dust on the surface of aluminum electrode foil according to claim 1, characterized in that: The concentration of the sulfuric acid solution in step S3 is 0.1-1.0 mol / L.

5. The method for detecting foil dust on the surface of aluminum electrode foil according to claim 1, characterized in that: The amount of the shredded aluminum foil added in step S3 is such that the aluminum content in the sulfuric acid solution reaches 0.6 mol / L.

6. The method for detecting foil dust on the surface of aluminum electrode foil according to claim 1, characterized in that: The soaking time in step S4 is 0.5-3 min.

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