JP5250320B2 - Method for producing positive electrode plate for alkaline storage battery and method for producing alkaline storage battery - Google Patents

Description

  The present invention relates to a method for producing a positive electrode plate for an alkaline storage battery and a method for producing an alkaline storage battery. More specifically, the present invention relates to a minute metal foreign matter that is mixed in a positive electrode plate of a predetermined shape provided in the alkaline storage battery and causes a short circuit of the alkaline storage battery. The present invention relates to a method for producing a positive electrode plate for an alkaline storage battery and a method for producing an alkaline storage battery that can be selectively removed.

  In the production process of alkaline storage battery, in order to increase the reliability of alkaline storage battery, in the production process of completed storage battery or storage battery, it is inspected whether the storage battery is good or defective, and if it is defective It is generally done to eliminate it before putting it on the market.

  For example, in the manufacturing process of an alkaline storage battery, when a minute metal that dissolves at a positive electrode potential and precipitates at a negative electrode potential is mixed as a foreign substance in the electrode substrate on which the positive electrode plate is formed, charging and discharging are repeated in the completed battery. In some cases, the minute metal foreign matter dissolves from the positive electrode plate and precipitates on the negative electrode plate, and further grows in a dendrite shape on the negative electrode plate to cause a short circuit between the positive electrode plate and the negative electrode plate.

  Therefore, based on the X-ray transmission image obtained by irradiating the electrode substrate with the electrode substrate as an inspection object and irradiating the electrode substrate, it is detected whether or not a minute metal foreign matter exists on the electrode substrate. There is technology. According to this technique, when a minute metal foreign matter is present, a portion where the minute metal foreign matter is present is selectively removed from the electrode substrate (see, for example, Patent Document 1).

By the way, among the alkaline storage batteries, in the nickel metal hydride battery, a foamed nickel plate made of a nickel porous body having a three-dimensional network structure is used for the electrode substrate which is a material of the positive electrode plate. In such a foamed nickel plate, copper or brass (copper alloy) may be mixed as the above-mentioned fine metal foreign matter in the manufacturing process or the like.
JP 2006-179424 A

  However, there are innumerable minute irregularities on the surface of such a foamed nickel plate, and in the foamed nickel plate, a minute metallic foreign matter having a particle shape similar to the irregular shape or harmless nickel particles It is difficult to discriminate them with good sensitivity and selectively remove them.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain an alkaline storage battery obtained by detecting and removing fine metallic foreign matters present on a positive electrode substrate (positive electrode plate) with good sensitivity. It is providing the manufacturing method of the positive electrode plate for alkaline storage batteries which can improve the reliability of this, and the manufacturing method of alkaline storage batteries.

  In order to solve the above problems, the invention described in claim 1 is a method of manufacturing a positive electrode plate formed from an electrode substrate and disposed in an alkaline storage battery, wherein the electrode substrate is conveyed as an inspection object. On the other hand, a primary screening process for detecting foreign matter distributed on the electrode substrate online based on the size thereof, and a metal to be detected as a minute metallic foreign matter that causes a short circuit of the battery in the portion where the foreign matter is detected A chemical solution adhering step for depositing a chemical solution containing a solvent in a solvent with a reagent that emits light in the presence of the substance; a light emitting portion detecting step for detecting an on-line portion emitted by the chemical solution on the electrode substrate; and the detected luminescence The gist is to include a defective portion removing step of selectively removing a portion as a defective portion where a minute metal foreign matter exists.

  According to this configuration, in the primary screening process, the foreign substance on the electrode substrate is detected online based on the size thereof, and further, the minute part that causes a short circuit of the battery in the chemical solution attaching process at the part where the foreign substance is detected. A chemical solution containing a reagent that emits light in the presence of a metal to be detected as a foreign metal is adhered. For this reason, in the primary screening process, even if foreign matter other than the fine metal foreign matter is detected by setting the inspection sensitivity high in order to reduce the inspection omission of the fine metallic foreign matter to be originally detected, the chemical solution attaching step Therefore, it is possible to eliminate detection of foreign matters that should not be detected. In other words, compared to the case where the inspection sensitivity is set to a constant value and the foreign substance on the electrode substrate is detected only in a single process based on its size, the inspection leakage of the minute metallic foreign substance can be reduced and It is also possible to reduce false detections that erroneously detect foreign objects other than metal foreign objects. This makes it possible to selectively remove the minute metal foreign matter from the electrode substrate with high accuracy. In addition, on the electrode substrate, a chemical solution containing a reagent that emits light in the presence of a metal to be detected as a minute metal foreign matter is selectively attached to a portion where the foreign matter is detected. For this reason, compared with the case where a chemical | medical solution is made to adhere over the full width direction of an electrode substrate, it also becomes possible to aim at the saving of the usage-amount of a chemical | medical solution. As a result, the positive electrode plate can be formed (collected) with a high yield from the electrode substrate, leading to a reduction in manufacturing cost. In addition, the obtained positive electrode plate has very little adhesion of fine metal foreign matter, and finally an alkaline storage battery having high reliability can be obtained.

  Invention of Claim 2 is a manufacturing method of the positive electrode plate for alkaline storage batteries of Claim 1, Comprising: The said electrode substrate is a foam nickel board, the said metal is copper, and the said reagent is luminol, The gist of the chemical solution containing the reagent is that it further contains hydrogen peroxide in a state of containing an alkaline substance in the solvent so as to exhibit alkalinity.

  According to this configuration, the electrode substrate is a nickel foam plate, the metal to be detected as a fine metal foreign material is copper, and the reagent is luminol, and the chemical solution containing the reagent contains an alkaline substance in the solvent and exhibits alkalinity. I did it. For this reason, it becomes possible to detect fine metallic foreign matter made of copper or a copper alloy with good sensitivity by utilizing the light emission phenomenon (photoluminescence phenomenon) of luminol using copper as a photocatalyst. Moreover, since a chemical solution containing luminol as a reagent soaks well into a foamed nickel plate having a three-dimensional network structure, luminol also emits luminol as a fine metal foreign substance existing inside the electrode substrate. It can be detected with good sensitivity. In addition, hydrogen peroxide, which is an oxidizing agent in the solvent, has the feature that no residue remains during volatilization, and can be removed almost completely by drying the electrode substrate with hot air, etc., and the degree of contamination of the work environment is low. It will be enough.

  Invention of Claim 3 is a manufacturing method of the positive electrode plate for alkaline storage batteries of Claim 2, Comprising: Ammonia is contained in the said chemical | medical solution in order to accelerate | stimulate the light emission phenomenon of luminol which uses copper as a photocatalyst. This is the gist.

  According to this configuration, since the chemical solution contains ammonia, the ammonia is coordinated to copper to form a water-soluble copper ammine complex, and the solubility of copper in the reagent that is an aqueous solution is enhanced. Thereby, the light emission phenomenon (photoluminescence phenomenon) of luminol using copper as a photocatalyst is promoted. In addition, ammonia has a lower viscosity than other alkaline substances such as sodium hydroxide, and has good permeability to the foamed nickel plate. As a result, the detection sensitivity of the fine metal foreign matter made of copper or copper alloy is further enhanced, and the fine metal foreign matter can be selectively removed with higher accuracy. Further, since ammonia itself releases an —OH group, the chemical solution becomes alkaline without adding an alkaline substance to the chemical solution containing luminol, and it is promoted that luminol is dissolved in the solvent. As a result, the amount of chemical substances used can be reduced. In addition, since ammonia is almost completely volatilized at about 80 ° C., it can be removed almost completely, for example, by drying the electrode substrate with hot air, effectively suppressing environmental pollution caused by ammonia and health damage to workers. sell. Furthermore, ammonia has the advantage that it is easily available, is inexpensive, and is suitable for industrial use in large quantities.

  Invention of Claim 4 is a manufacturing method of the positive electrode plate for alkaline storage batteries of Claim 3, Comprising: 0.05 mass% or more of luminol is 0.05 mass% or less with respect to the solvent in the said chemical | medical solution. It is included in the gist.

  According to the configuration, the chemical solution contains 0.05% by mass or more and 1% by mass or less of luminol with respect to the solvent. For this reason, it is possible to ensure a sufficient and sufficient luminol concentration to cause a light emission phenomenon using copper as a photocatalyst. That is, when the luminol concentration is less than 0.05% by mass, the emission intensity of the luminol does not decrease, and when the luminol exceeds 1% by mass, the amount used is excessive, leading to an increase in cost. It will be solved.

  Invention of Claim 5 is a manufacturing method of the positive electrode plate for alkaline storage batteries of Claim 3 or Claim 4, Comprising: The said chemical | medical solution is 2 mass% or more and 4 mass% or less with respect to a solvent. The gist is that ammonia is contained.

  According to this configuration, the chemical liquid contains 2% by mass or more and 4% by mass or less of ammonia with respect to the solvent. For this reason, it is possible to secure a necessary and sufficient ammonia concentration for causing a light emission phenomenon using copper as a photocatalyst. In other words, when the ammonia concentration is less than 2% by mass, the luminous intensity of luminol is not reduced, and when the amount of ammonia exceeds 4% by mass, the amount used is excessive. It also eliminates adverse effects on workers' health and further increases in costs.

  Invention of Claim 6 is a manufacturing method of the positive electrode plate for alkaline storage batteries as described in any one of Claims 1-5, Comprising: The said primary screening process is an electrode as said test object. An X-ray transmission inspection process for irradiating and transmitting X-rays on a substrate online, and identifying a portion where foreign matter is detected on the electrode substrate based on the obtained X-ray transmission image, The gist of the present invention is that an image intensifier is used to detect a portion emitted by the chemical solution.

  According to the same configuration, in the X-ray transmission inspection process as the primary screening process, the electrode substrate as the inspection object is irradiated with X-rays online and transmitted, and the electrode substrate is based on the obtained X-ray transmission image. The part where the foreign object exists was specified. By using X-rays in this way, it is possible to identify a portion where foreign matter is present efficiently even in an opaque electrode substrate that does not transmit visible light. Further, there is no possibility that the electrode substrate is altered or damaged by the X-ray irradiation. Furthermore, in the light emission portion detection step, a portion that emits light with a chemical solution using an image intensifier, that is, a portion where a minute metal foreign object that should be detected is present is detected. It can be identified with high sensitivity. As a result, it is possible to selectively remove the minute metal foreign matter with higher accuracy.

  Invention of Claim 7 is a manufacturing method of the positive electrode plate for alkaline storage batteries as described in any one of Claims 1-6, Comprising: The electrode substrate as said test object is paralleled in the width direction. The gist of the present invention is that the foreign matter and the light-emitting portion are detected on-line for each belt-like region.

  According to this configuration, the electrode substrate as an inspection object is divided into a plurality of rows of strip-like regions arranged in parallel in the width direction, and minute metal foreign matter is inspected online for each strip-like region. As a result, the electrode substrate is divided into a plurality of portions in the width direction by the plurality of strip-shaped regions, and the foreign matter is inspected. That is, in the primary screening process, a foreign substance is detected for each band-like region, and the chemical solution is attached to the foreign substance within the range of each band-like region in the chemical solution attaching step. For this reason, the electrode substrate is inspected simultaneously in the entire width direction, and compared with the case where the chemical solution is adhered over the entire width direction, the adhesion area of the chemical solution can be reduced. Consumption will be further reduced.

  Invention of Claim 8 is a manufacturing method of the positive electrode plate for alkaline storage batteries as described in any one of Claims 1-7, Comprising: In the said defective part removal process, it is the thickness of the said electrode substrate. The gist is that the defective portion is removed by punching in a direction.

  According to the configuration, in the defective portion removing step, the defective portion of the electrode substrate is removed by a punching process that punches in the thickness direction of the electrode substrate. For this reason, for example, when the electrode substrate is cut into a strip shape to form (collect) the positive electrode plate, the mass of the positive electrode plate in which punching holes are punched by the punching process is reduced from the specified mass. By measuring the mass, it is possible to select a good positive electrode plate free from fine metallic foreign matter.

  The invention according to claim 9 is the method of manufacturing a positive electrode plate for an alkaline storage battery according to claim 8, wherein the electrode substrate is mounted when the frequency is smaller than a predetermined value according to the frequency of the punching process. When the frequency is higher than a specified value, the speed at which the electrode substrate is transferred is decreased, and when the frequency is substantially equal to a specified value, the speed at which the electrode substrate is transferred is increased. The main point is to maintain the above.

  According to this configuration, according to the frequency of the punching process, when the frequency is less than a specified value, the electrode substrate transfer speed is increased, and when the frequency is greater than the specified value, the electrode substrate transfer speed is increased. In addition, when the frequency is substantially equal to the specified value, the conveyance speed of the electrode substrate is maintained. For this reason, the frequency of punching processing can be maintained at a substantially constant rate per hour, and when the frequency of punching processing is high, the burden on various inspection devices and punching devices can be reduced, and inspection errors can be prevented. In addition to being able to prevent, when the frequency of punching treatment is low, the production rate of the positive electrode plate for an alkaline storage battery can be increased and its production efficiency can be increased.

  Invention of Claim 10 is a manufacturing method of the positive electrode plate for alkaline storage batteries of Claim 8 or Claim 9, Comprising: When the frequency of the said punching process is larger than a regulation value, it removes by the said punching process The gist is that the area of the electrode substrate is enlarged.

  According to this configuration, when the frequency of the punching process is larger than the specified value, the area of the electrode substrate removed by the punching process is increased. For this reason, it is possible to selectively remove even more minute and difficult to detect metal foreign objects that are considered to exist with high accuracy around the portion where the fine metal foreign objects are detected on the electrode substrate, and the obtained alkaline storage battery The reliability can be further improved.

  Invention of Claim 11 is a manufacturing method of the alkaline storage battery by which a positive electrode plate, a negative electrode plate, and electrolyte solution are arrange | positioned, Comprising: The positive electrode for alkaline storage batteries as described in any one of Claims 1-10. The gist is to produce the positive electrode plate using a method for producing a plate.

  According to this configuration, when the alkaline storage battery is manufactured, by using the method for manufacturing a positive electrode plate for an alkaline storage battery according to any one of claims 1 to 10, a mixture of minute metal foreign matters on the positive electrode plate is present. It is possible to manufacture an alkaline storage battery that is scarce and has high reliability.

  The invention according to claim 12 is a method for manufacturing an alkaline storage battery having a positive electrode plate formed from an electrode substrate, and the electrode substrate is irradiated with X-rays online while being transported as an inspection object. X-ray transmission inspection process for identifying the portion where the foreign matter is detected on the electrode substrate based on the obtained X-ray transmission image, and the cause of the short circuit of the battery in the portion where the foreign matter is detected A chemical solution adhesion step for online deposition of a chemical solution containing luminol in a solvent that emits light in the presence of a metal to be detected as a minute metal foreign matter, and light emission for detecting on-line the portion of the electrode substrate that has emitted light by the chemical solution The gist of the invention is to include a partial detection step and a defective portion removal step of selectively removing the detected light emitting portion as a defective portion in which a minute metal foreign matter exists.

  According to the same configuration, in the X-ray transmission inspection process, the foreign substance on the electrode substrate is detected online based on the size thereof, and further, the portion where the foreign substance is detected causes a short circuit of the battery in the chemical solution attaching process. A chemical solution containing a reagent that emits light in the presence of a metal to be detected as a minute metal foreign matter is attached. For this reason, in the X-ray transmission inspection process, even if foreign matter other than the fine metal foreign matter is detected by setting the inspection sensitivity high in order to reduce the inspection omission of the fine metallic foreign matter that should be detected originally, In the process, it is possible to eliminate detection of foreign matters that should not be detected originally. In other words, compared to the case where the inspection sensitivity is set to a constant value and the foreign substance on the electrode substrate is detected only in a single process based on its size, the inspection leakage of the minute metallic foreign substance can be reduced and It is also possible to reduce false detections that erroneously detect foreign objects other than metal foreign objects. This makes it possible to selectively remove the minute metal foreign matter from the electrode substrate with high accuracy.

  Further, in the X-ray transmission inspection process, the electrode substrate as an inspection object is irradiated with X-rays online and transmitted, and a portion where foreign matter exists on the electrode substrate is specified based on the obtained X-ray transmission image. I did it. By using X-rays in this way, it is possible to identify a portion where foreign matter is present efficiently even in an opaque electrode substrate that does not transmit visible light. Further, there is no possibility that the electrode substrate is altered or damaged by the X-ray irradiation.

  Furthermore, since the reagent is luminol, it is possible to detect fine metallic foreign matters made of copper or copper alloy with good sensitivity by utilizing the luminescence phenomenon (chemiluminescence phenomenon) of luminol using copper or iron as a photocatalyst. become. Moreover, since a chemical solution containing luminol as a reagent soaks well into a foamed nickel plate having a three-dimensional network structure, luminol also emits luminol as a fine metal foreign substance existing inside the electrode substrate. It can be detected with good sensitivity.

  Moreover, in the electrode substrate, a chemical solution containing a solvent is selectively attached to the portion where the foreign material is detected, and a reagent that emits light in the presence of the metal to be detected as a fine metal foreign material is attached in the entire width direction of the electrode substrate. Compared with the case where the chemical solution is adhered over the whole area, the amount of the chemical solution used can be reduced.

  As a result, the positive electrode plate can be formed (collected) with a high yield from the electrode substrate, leading to a reduction in manufacturing cost. In addition, the obtained positive electrode plate has very little adhesion of fine metal foreign matter, and finally an alkaline storage battery having high reliability can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the reliability of the obtained alkaline storage battery can be improved by detecting and removing the fine metal foreign material mixed in the positive electrode plate with good sensitivity.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings.
As shown in FIG. 1A, an alkaline storage battery 1 according to this embodiment is a nickel-metal hydride storage battery used as a power source for an electric vehicle (PEV) or a hybrid vehicle (HEV), and takes the form of a so-called rectangular battery module. ing.

  The alkaline storage battery 1 includes a battery container 10 having a substantially rectangular parallelepiped shape, a plurality of power generation elements 11 housed in the battery container 10, an external positive electrode terminal 12a and an external negative electrode terminal 12b for electrical connection with an external device. An alkaline electrolyte (not shown) mainly composed of potassium hydroxide is injected into the battery container 10.

  The battery container 10 includes a container upper surface portion 13a having a substantially rectangular shape in plan view, a container lower surface portion 13b substantially parallel to the container upper surface portion 13a, and a first container side surface connecting a short side of the container upper surface portion 13a and a short side of the container lower surface portion 13b. A section 14a and a second container side face 14b, and a third container side face 14c and a fourth container side face 14d that connect the long side of the container upper face part 13a and the long side of the container lower face part 13b. In addition, the inside of the battery container 10 is divided into six spaces substantially evenly by five container partition walls 14e,... Substantially parallel to the first and second container side surfaces 14a, 14b.

  In each space, the power generation element 11 is accommodated and constitutes a cell 15 which is a single battery. Each power generating element 11 is configured by alternately stacking positive plates 11a and negative plates 11b so as to sandwich separators 11c made of a sulfonated polypropylene material. The positive electrode plate 11a and the negative electrode plate 11b are in contact with the electrolytic solution. Each power generating element 11 is made of a conductive material (nickel-plated steel plate) and is provided with a substantially plate-like and substantially rectangular positive electrode current collector plate 16a and negative electrode current collector plate 16b. Each positive electrode current collector plate 16a and negative electrode current collector plate 16b are connected to each positive electrode current collector plate 16a and negative electrode current collector plate 16b of an adjacent cell 15 through a connection member (not shown) penetrating the container partition wall 14e. Each cell 15 is electrically connected in series. Furthermore, the positive electrode current collector plate 16a of the cell 15 positioned closest to the external positive electrode terminal 12a is electrically connected to the external positive electrode terminal 12a by being welded to the external positive electrode terminal 12a penetrating the first container side surface portion 14a. Has been. The negative electrode current collector plate 16b of the cell 15 positioned closest to the external negative electrode terminal 12b is welded to the external negative electrode terminal 12b penetrating the second container side surface portion 14b, thereby being electrically connected to the external negative electrode terminal 12b. Yes. With such a configuration, a rectangular battery module is formed.

As shown in FIG. 1 (b), the positive electrode plate 11a has a positive electrode active material containing nickel hydroxide by a known method after cutting an electrode substrate (electrode substrate 110) having foamed nickel as a core material into a large plate. A paste in which a conductive agent and a binder are appropriately mixed is applied. Further, it is cut and molded into a predetermined shape (a strip shape of about 5 cm × 10 cm) after pressing. On the other hand, the negative electrode plate 11b is made into a paste form by adding a conductive agent and a binder to a fine powder of hydrogen storage alloy of MmNi ₅ and applied to a metal porous plate (punching metal) and pressed into a predetermined shape ( (Strip shape of about 5 cm × 10 cm).

  In the present embodiment, in the electrode substrate 110 (see FIG. 2) before the positive electrode plate 11a is cut out (collected) into a predetermined shape, the metal is dissolved at the positive electrode potential of the alkaline storage battery 1 and deposited at the negative electrode potential. It is assumed that there is a minute metal foreign object (fine metal foreign object Me) made of a copper alloy (brass) containing copper (Cu).

  In addition, in the present embodiment, it is an object to detect a minute metal foreign object made of a copper alloy having a particle size of 100 μm or more from the electrode substrate, and to remove the portion containing the minute metal foreign object from the electrode substrate as a defective portion. . In addition, it is thought that this fine metal foreign matter is mixed as a contaminant (contamination) at the stage of manufacture of the foamed nickel plate (electrode substrate) as a core material, or adheres as dust at the storage or transportation stage. . Examples of the “metal that dissolves at the positive electrode potential and precipitates at the negative electrode potential” include lead (Pb), silver (Ag), tin (Sn), and the like, in addition to copper (Cu).

  When such a minute metal foreign matter is present in the positive electrode plate 11a, in the manufactured alkaline storage battery 1, it dissolves in the positive electrode plate 11a as time passes, moves through the electrolyte, precipitates on the negative electrode plate 11b, and is positive electrode plate. There is a case where a short circuit phenomenon occurs between 11a and the negative electrode plate 11b. In particular, when copper is deposited on the negative electrode plate 11b, it becomes a needle-like crystal and grows in a dendrite (dendritic) shape toward the positive electrode plate 11a and easily causes a short circuit. It is desirable to remove.

  Therefore, in the present embodiment, in the manufacturing process of the positive electrode plate 11a of the alkaline storage battery 1, a minute metal foreign object inspection process described below is provided, and whether or not there is a minute metal foreign object made of copper or a copper alloy on the electrode substrate 110. Is detected. And when it exists, the defective part in which the said minute metal foreign material exists is selectively removed from the electrode substrate 110. FIG.

  Hereinafter, referring to FIG. 2 to FIG. 6, fine metal foreign substances are brought online (here, the initial transport speed) from a long electrode substrate 110 (in this case, one having a width of 200 mm) as an inspection object. The fine metal foreign matter detection step and the punching step (defective portion removal step) as the fine metal foreign matter inspection step to be inspected at 0.17 m / sec will be described in detail. The minute metal foreign matter detection step further includes an X-ray transmission inspection step (primary screening step), a chemical solution adhesion step, and a light emission partial detection step.

  First, with reference to FIG. 2, a description will be given of the minute metal foreign object inspection apparatus 2 used in the minute metal foreign object inspection process. In the apparatus 2, nickel nickel (foamed Ni) is extracted from the hoop 20a located at the beginning of the inspection process. A long electrode substrate 110 as an inspection object to be a core material is unwound at a predetermined speed (initial conveyance speed 0.17 m / sec). The electrode substrate 110 is optically driven by various inspection devices provided in the inspection process before being wound around the hoop 20b positioned at the end of the inspection process at the same predetermined speed via the drive motor 20c. Using the means, a minute metal foreign object made of copper or a copper alloy is detected online, and a defective portion in which the minute metal foreign object exists is removed by punching (punching).

  The minute metal foreign matter inspection device 2 includes an X-ray transmission inspection device 21, a chemical spraying device 22, an optical sensor device 24, a punching device 25, a cleaning water spraying device 26, and a hot air drying device 27 as various inspection devices. . These various inspection devices and the drive motor 20c are electrically connected to the control device 28 in a controllable state. Further, in the minute metal foreign matter inspection device 2, a dancer roll 23 for holding the electrode substrate 110 is provided between the chemical solution spraying device 22 and the optical sensor device 24 for a predetermined time (about 0 to 1 minute). Yes. This predetermined time (the holding time of the electrode substrate 110) can be arbitrarily set in the dancer roll 23. These various inspection devices and the like are accommodated in the dark room 20 together with the electrode substrate 110 as an inspection object in order to improve inspection efficiency by an optical method. Further, the dark room 20 is provided with an exhaust duct device 29, which is configured to volatilize in the room and discharge various chemical substances present in the air to the outside.

  In the X-ray transmission inspection apparatus 21, the X-ray is irradiated to the electrode substrate 110 which is controlled by the control apparatus 28 and is conveyed at a predetermined speed by the X-ray irradiator 21a. Then, an X-ray transmission inspection signal (X-ray transmission image) is acquired from the X-rays transmitted through the electrode substrate 110 by the X-ray image sensor 21b having the inspection sensitivity adjusted, and based on the X-ray transmission inspection signal, the X-ray transmission inspection signal is acquired. Via the control device 28, for example, metal particles made of copper or a copper alloy (brass or the like) or harmless nickel particles as a minute metal foreign object Me as shown in FIG. 3 are detected.

  Here, the X-ray transmission inspection device 21 is not particularly limited, but TFX110SX (model number) manufactured by Token Co., Ltd. is used, and the inspection cusp is set to 70 or more and 90 or less. This “inspection peak value” is an index indicating the inspection sensitivity of the apparatus 21. If a small number is set, the determination becomes loose, and the ratio of squeezing (sieving off) by the apparatus 21 decreases ( If the number is set to a large value, the judgment becomes stricter, and the ratio of squeezing by the device 21 increases (incorrect detection increases).

  Specifically, as shown in FIG. 4A, in the state where the inspection sensitivity of the X-ray transmission inspection apparatus 21 is low (the inspection cusp value of the inspection apparatus 21 is less than 64), the minute metal foreign matter made of copper or copper alloy Me having a particle size of 300 μm can be detected and can be rejected. However, those having a particle size of 200 μm cannot be detected, pass the inspection, and cause an inspection failure. At this time, in the X-ray transmission inspection apparatus 21, as shown in FIGS. 4D and 4I, the X-ray transmission inspection signal of the minute metal foreign matter Me (particle diameter: 300 μm) has a large signal intensity S (S Detected as large). Further, as shown in FIGS. 4D and 4I, the X-ray transmission inspection signal of the minute metal foreign matter Me (particle diameter: 200 μm) is detected as a medium signal intensity S (medium S).

  In addition, as shown in FIG. 4B, in the state where the inspection sensitivity of the X-ray transmission inspection apparatus 21 is medium (the inspection cusp value of the inspection apparatus 21 is greater than 65 and less than 84), the minute metallic foreign matter Me Can detect that the particle size is 100 μm, and can reject the inspection. However, at this time, nickel particles that should not be detected originally fail the inspection, and the number of false detections gradually increases. At this time, as shown in FIGS. 4 (d) and (iii), in the X-ray transmission inspection apparatus 21, the X-ray transmission inspection signal of the minute metal foreign matter Me (particle diameter: 100 μm) has a small signal intensity S (S Small).

  Furthermore, as shown in FIG. 4C, in the state where the inspection sensitivity of the X-ray transmission inspection apparatus 21 is high (the inspection cusp value of the inspection apparatus 21 exceeds 85), the fine metal foreign matter Me has a particle size of A thing of 100 micrometers can be detected naturally, and it can be set as inspection failure. However, at this time, the frequency of nickel particle inspection failure increases, and false detection further increases.

  Returning to FIG. 2, in the chemical solution spraying device 22, a chemical solution containing a reagent that emits light in the presence of a metal (here, copper) to be detected as the minute metal foreign matter Me is sprayed (attached) to the electrode substrate 110 online. .

  Specifically, luminol (Luminol: 5-amino-2,3-dihydro-1,4-phthalazinedione) is used as a reagent, and the chemical solution containing the luminol is alkaline with ammonia as an alkaline substance in pure water. It is trying to present. The reason why the chemical solution (aqueous solution) is alkaline is that a strong chemiluminescence phenomenon (luminescence phenomenon) of greenish blue due to luminol occurs in association with oxidation of luminol in the alkaline aqueous solution.

Specifically, pure ternary reagent of luminol (molecular formula: C ₈ H ₇ N ₃ O ₂ ) -hydrogen peroxide (chemical formula: H ₂ O ₂ ) -ammonia (chemical formula: NH ₄ OH) is used as the chemical solution. Use one dissolved in water. The reason for using ammonia in this way is to promote the chemiluminescence phenomenon (luminescence phenomenon) of luminol using copper as a photocatalyst. That is, ammonia is coordinated to copper to form a water-soluble copper ammine complex, and the solubility of copper in the chemical solution that is an aqueous solution (copper ionization) is promoted. This effectively enhances the light emission phenomenon of luminol using copper as a photocatalyst.

  Here, the concentration of luminol is 0.05% by mass or more and 1% by mass or less, and preferably 0.05% by mass or more and 0.08% by mass or less with respect to pure water as a solvent. . As a result, when the luminol concentration is less than 0.05% by mass, the light emission intensity of the luminol is not reduced, and when the luminol exceeds 1% by mass, the amount used is excessive and the cost increases. It will also be resolved to lead to.

  Moreover, it is preferable that the density | concentration of the hydrogen peroxide which is an oxidizing agent shall be the range of 1 mass% or more and 10 mass% or less with respect to the pure water as a solvent. By setting it as this range, pH of the chemical | medical solution containing luminol can be set to 10-11 suitable for generation | occurrence | production of the light emission phenomenon. The hydrogen peroxide has good volatility, and can be removed almost completely by drying the electrode substrate 110 with hot air or the like, and the degree of contamination of the working environment can be reduced.

  Furthermore, the concentration of ammonia is preferably in the range of 2% by mass or more and 4% by mass or less with respect to pure water as a solvent based on the experimental results shown in Table 1 in <Experimental Example 1> described later. As a result, the luminous intensity of luminol is not reduced when ammonia is less than 2% by mass, and when ammonia exceeds 4% by mass, the amount used is excessive, and the odor becomes stronger. It will be possible to eliminate the worsening of the situation, the health damage of workers, and the cost increase.

  As shown in FIG. 2, in the optical sensor device 24, the portion of the electrode substrate 110 that has emitted light by the chemical solution is detected using an image intensifier 24a that has a photomultiplier action and multiplies the amount of weak light. Is done. Then, a video signal is output from the image intensifier 24a to the control device 28, and image processing is performed in the control device 28 to obtain an image with contrast. The photosensor device 24 is darkened in order to improve the light emission detection effect by the photomultiplier effect of the image intensifier 24a. That is, in this embodiment, the environment in which the luminol emission phenomenon is detected is a double dark room by the photosensor device 24 and the dark room 20. Further, from the experimental results shown in Table 1 in <Experimental Example 1> and Table 2 in <Experimental Example 2> to be described later, the luminescence phenomenon caused by luminol necessary for detection by the image intensifier 24a is applied to the test object. After that, it started after 3 seconds, and the light emission intensity became almost constant after 30 seconds, and it has been confirmed that the light emission phenomenon continues with this light emission intensity. For this reason, the time for the electrode substrate 110 to pass between the chemical spraying device 22 and the optical sensor device 24 is 3 seconds or more and 30 seconds or less in the dancer roll 23 from the viewpoint of obtaining a light quantity detectable by the image intensifier 24a. Preferably, it is set to 3 seconds or more and 10 seconds or less.

  In the present embodiment, the image intensifier 24a is not particularly limited. However, XX2050 (model number) manufactured by DELFT is used, and the light multiplication factor (gain) is set to 10,000 times. Then, for the minute metal foreign matter Me made of copper or a copper alloy having a particle size of 100 μm or more, a luminol light emission phenomenon occurs, which can eventually be rejected, but is detected as a foreign matter by the X-ray transmission inspection device 21. As a result, the nickel particles that failed the inspection do not cause the luminol luminescence phenomenon and can finally pass the inspection.

  That is, as described above, in the present embodiment, in a state where there is no false detection of harmless nickel particles, a minute metal foreign object Me made of copper or a copper alloy having a particle size of 100 μm or more is detected, and the minute metal foreign object Me is detected. The object is to remove the included portion from the electrode substrate 110 as a defective portion. For this reason, even if the X-ray transmission inspection apparatus 21 is set to any inspection sensitivity from low sensitivity to high sensitivity shown in FIG. 4A to FIG. The goal cannot be achieved.

  However, by using the chemical spraying device 22 and the optical sensor device 24 in addition to the X-ray transmission inspection device 21 as in the present embodiment, the medium inspection sensitivity (65 <inspection kurtosis value) shown in FIG. By setting the X-ray transmission inspection apparatus 21 to <84) and further inspecting with the optical sensor apparatus 24 at this inspection sensitivity, the results shown in Table A below are obtained. That is, in the X-ray transmission inspection apparatus 21, nickel that is a foreign matter other than the fine metal foreign matter Me is set by setting the inspection sensitivity to a moderate level in order to reduce the inspection leakage of the fine metallic foreign matter Me to be originally detected. Even when particles are detected, the chemical spraying device 22 can eliminate detection of nickel particles that should not be detected.

上表Ａより、検査感度が低の（１）では、微小金属異物Ｍｅが全く検出されず、発光による検査結果を踏まえた異物を見逃す割合（頻度）は大であり、総合評価で「不適」となった。また、検査感度が中の（２）では、微小金属異物Ｍｅが検出され、ニッケル粒子（Ni粒子）の誤検出が次第に増加するが、異物を見逃す割合（頻度）は中程度であって、パンチング処理の頻度（回数）は過多とならず、これにより総合評価で「適」の結果が得られた。さらに、検査感度が高の（３）では、微小金属異物Ｍｅが検出され、異物を見逃す割合は小となるが、ニッケル粒子の誤検出がさらに増加し、検査回数の増大により、総合評価で「不適」となった。 Table A below shows the inspection result of the minute metal foreign object Me when the inspection sensitivity in the X-ray transmission inspection is changed in three stages in the minute metal foreign object inspection apparatus 2 of the present embodiment.

From Table A above, when the inspection sensitivity is low (1), the minute metal foreign object Me is not detected at all, and the rate (frequency) of missing the foreign object based on the inspection result by light emission is large. It became. Further, in (2) where the inspection sensitivity is medium, minute metal foreign matter Me is detected and the false detection of nickel particles (Ni particles) gradually increases, but the rate (frequency) of missing foreign matters is moderate, and punching The frequency (number of times) of processing did not become excessive, and this gave a “suitable” result in the overall evaluation. Furthermore, in (3) where the inspection sensitivity is high, the minute metal foreign matter Me is detected and the rate of missing the foreign matter is small, but the false detection of nickel particles is further increased, and the number of inspections is increased. Unsuitable ”.

  As shown in FIG. 2, in the punching device 25, the light-emitting portion that is controlled by the control device 28 and detected in the electrode substrate 110 is, for example, a defective portion in which copper or a copper alloy that is the minute metal foreign matter Me exists. , And selectively removed by punching using the punching blade 25a.

  As shown in FIG. 5, in this embodiment, each inspection and removal operation of foreign matters by the X-ray transmission inspection device 21, the chemical spraying device 22, the optical sensor device 24, and the punching device 25 is performed as an electrode substrate as an inspection object. 110 is divided into three (a plurality of) strip-like regions I, II, and III arranged in parallel in the width direction, and is configured to be performed on-line for each strip-like region I, II, and III.

  Specifically, the X-ray transmission inspection apparatus 21 is disposed in the inspection process of the electrode substrate 110, and the X-ray irradiator 21a and the X-ray image sensor 21b are opposed to each other in each of the belt-like regions I, II, and III. In the state, the electrode substrate 110 as an inspection object is sandwiched. Then, an X-ray transmission inspection signal (X-ray transmission image) is acquired by the X-ray image sensor 21b from the X-rays emitted from each X-ray irradiator 21a and transmitted through the electrode substrate 110.

Next, in each strip | belt-shaped area | region I, II, and III, the chemical | medical solution spraying apparatus 22 is arrange | positioned, respectively, and the said chemical | medical solution is sprayed on the electrode substrate 110 online.
Subsequently, a photosensor device 24 that has been made into a dark room is disposed in the inspection process of the electrode substrate 110, and in each of the belt-like regions I, II, and III, the portion emitted by the chemical solution is detected by the image intensifier 24a.

  A punching device 25 is disposed in each of the belt-like regions I, II, and III, and a punching process using the punching blade 25a is used to punch the periphery of the detected light emitting portion on the electrode substrate 110 with a diameter of about 1 cm. By perforating through the hole 110a, it is selectively removed as a defective portion where copper or a copper alloy, which is a minute metal foreign material Me, is present.

  Returning to FIG. 2, the cleaning water spraying device 26 is controlled by the control device 28, and in order to wash off the chemical solution remaining on the electrode substrate 110, a cleaning solution made of pure water is injected. Here, a plurality of spray nozzles 26a,... Are provided, and the cleaning liquid is sprayed from each of the spray nozzles 26a,... Toward the electrode substrate 110, and the used cleaning liquid is collected in a recovery tank (not shown). It is configured.

  In the hot air drying device 27, the pure water as the cleaning liquid remaining on the electrode substrate 110 is controlled by the control device 28 and dried together with the remaining chemical liquid by hot air from the blower 27 a and removed. Then, the dried electrode substrate 110 is wound around the hoop 20b.

  The washing water spraying device 26 and the hot air drying device 27 can be omitted as appropriate depending on the state of the electrode substrate 110 after the punching process, for example, the remaining state of ammonia on the electrode substrate 110.

<Experimental example 1>
In Experimental Example 1, the addition amounts of luminol and hydrogen peroxide were fixed at 0.1% by mass and 2% by mass with respect to pure water, respectively, and various chemical solutions were obtained by changing the concentration of ammonia (NH ₄ OH). The pH of each chemical solution, the odor, and the luminous intensity of luminol when applied to the test object were evaluated off-line (fixed state, non-transport state). Here, as the inspection object, the one in which the particles of brass (particle size: 100 μm) as if the fine metal foreign material Me was adhered on the foamed nickel plate was used. Further, as the inspection device, the optical sensor device 24 (see FIG. 2) was used, the photomultiplier (gain) of the image intensifier 24a was set to 10,000 times, and the portion emitted by the chemical solution was detected. The obtained results are shown in Table 1 below.

本実験例１において、ルミノールによる発光現象（イメージインテンシファイア２４ａにより検出に必要な発光）は、前記薬液を検査対象物に塗布した後、３秒後に開始した。これは、薬液に対し、黄銅から銅がイオン化して溶出するまでに少なくとも３秒程度を要するためと推定される。したがって、前記検査対象物として電極基板１１０を使用し、オンラインで発光を検出する場合、薬液を電極基板１１０に吹付けてから発光の検出までに少なくとも３秒以上の時間差を設定することが好ましい。また、オンラインでルミノールによる発光現象を検出する場合は、発光の残像が線状に観察されるので、検出が容易となることが確認された。

In Experimental Example 1, the light emission phenomenon by luminol (light emission necessary for detection by the image intensifier 24a) started 3 seconds after the chemical solution was applied to the test object. This is estimated because it takes at least about 3 seconds for copper to ionize and elute from the brass. Therefore, when the electrode substrate 110 is used as the inspection object and light emission is detected online, it is preferable to set a time difference of at least 3 seconds from the time when the chemical solution is sprayed to the electrode substrate 110 until the light emission is detected. In addition, when detecting the luminescence phenomenon due to luminol online, it was confirmed that the detection was easy because the afterimage of luminescence was observed linearly.

  In addition, in this Experimental Example 1, an optimal chemical solution for detecting the luminol emission phenomenon by brass as the fine metal foreign material Me is considered to be luminol in addition to the luminescence intensity obtained, in addition to the odor of ammonia. It was confirmed that 1% by mass, 2% by mass of hydrogen peroxide, and 2% by mass of ammonia were each contained in pure water.

<Experimental example 2>
In this Experimental Example 2, as inspection objects, metal particles (here, copper particles) having particle diameters different from 150 μm, 250 μm, and 500 μm were prepared on a nickel foam plate, and the fine metal foreign object Me was prepared. For each estimated particle size (μm), the relationship between time and light emission phenomenon and the light emission area were investigated offline. Here, the chemical solution used contained 0.1% by mass of luminol, 2% by mass of hydrogen peroxide, and 2-4% by mass of ammonia in pure water. Further, here, as in <Experimental Example 1>, the photosensor device 24 was used, the photomultiplier (gain) of the image intensifier 24a was set to 10,000 times, and the portion emitted by the chemical solution was detected. . The obtained results are shown in Table 2 below.

尚、本実験例２において、金属粒子の粒径（μｍ）に依らず、ルミノールは、該ルミノールを含む薬液を検査対象物に添加した直後から発光を開始し、その発光強度は３０秒後にほぼ一定となり、以降、この発光強度のままで発光現象が継続した。また、発光面積は、金属粒子の粒径（μｍ）の影響が見られ、粒径が大きい程、発光面積が大きくなる傾向が観察された。これは、薬液に溶出した銅イオンが金属粒子の周囲に滞留したためであり、金属粒子の粒径が大きい程、銅イオンの滞留が大きいためと考えられる。

In this Experimental Example 2, regardless of the particle size (μm) of the metal particles, the luminol started to emit light immediately after the chemical solution containing the luminol was added to the test object, and the emission intensity was almost 30 seconds later. After that, the light emission phenomenon continued with this light emission intensity. In addition, the light emission area was affected by the particle size (μm) of the metal particles, and it was observed that the larger the particle size, the larger the light emission area. This is because the copper ions eluted in the chemical solution stayed around the metal particles, and the larger the particle size of the metal particles, the larger the stay of copper ions.

  Next, a method for inspecting a minute metal foreign material performed by the above-described minute metal foreign material inspection apparatus 2 will be described with reference to FIG. By this inspection method, fine metal foreign matters such as copper or copper alloy mixed in the positive electrode plate 11a having a predetermined shape arranged in the alkaline storage battery 1 are removed. The inspection method is performed by the minute metal foreign object inspection apparatus 2, but can also be performed by a minute metal foreign object inspection apparatus having another configuration.

  As shown in FIG. 6, first, as an inspection object, a long electrode substrate 110 having a foamed nickel (foamed Ni) wound around the hoop 20a as a core material is prepared, and the electrode substrate 110 is formed from the hoop 20a. The speed for winding up is set (S101). Here, the winding speed is set by the control device 28 to 0.17 m / sec as an initial conveyance speed for winding the electrode substrate 110 onto the FOUP 20b by the drive motor 20c.

  Next, the electrode substrate 110 is wound up from the hoop 20a at the above speed (S102). Then, the conveyed electrode substrate 110 is irradiated with X-rays online to obtain an X-ray transmission image, and on the basis of the X-ray transmission image, a minute metal foreign object Me (see FIG. 3) is detected (S103; X-ray transmission inspection process). Here, the X-ray irradiator 21a (see FIGS. 2 and 5) of the X-ray transmission inspection apparatus 21 irradiates the electrode substrate 110 with X-rays, and the image sensor 21b (see FIGS. 2 and 5) irradiates the electrode substrate. An X-ray transmission inspection signal (X-ray transmission image) is acquired from the X-rays transmitted through 110, and foreign matter is detected via the control device 28 based on the X-ray transmission inspection signal.

  Next, a chemical solution containing a reagent that emits light in the presence of copper (copper ions) in pure water is attached online to the portion where the foreign matter is detected (S104; chemical solution attaching step). Here, luminol is used as a reagent, and an alkaline aqueous solution containing 1% by mass of luminol, 2% by mass of ammonia, and 2% by mass of hydrogen peroxide is used for the chemical solution as a solvent. Luminol can be appropriately changed within a range of 0.05% by mass or more and 1% by mass or less as long as a sufficient light emission amount is secured.

  Subsequently, on the electrode substrate 110, a portion emitted by the chemical solution is detected (S105; light emission portion detection step). Here, using the image intensifier 24a (see FIGS. 2 and 5) of the optical sensor device 24, fine particles (see FIG. 3) made of copper or a copper alloy exist on the electrode substrate 110, and light is emitted by the chemical solution. The detected part is detected.

  Then, the detected light emitting portion is selectively removed as a defective portion where the minute metal foreign matter Me exists (S106; defective portion removing step). Here, the defective portion is removed by the punching process by the punching device 25 (see FIGS. 2 and 5).

  At this time, the control device 28 counts the frequency (number of times / sec) of occurrence of the punching process executed by the punching device 25 at a predetermined sampling period (S107). Then, the control device 28 compares this frequency with a predetermined specified value, and if it is determined that the frequency is smaller than the specified value, the control device 28 controls the drive motor 20c. In step S101, the hoop 20a is controlled. The winding speed is increased (S108a).

  On the other hand, in other cases, that is, when the value is larger than or substantially equal to the specified value, the process proceeds to step S109 (S109). The drive motor 20c is controlled, and in step S101, the winding speed of the hoop 20a is reduced (S109a).

  And when it is judged that it is substantially equal to a predetermined specified value, while the winding speed of the hoop 20a is maintained, the washing water spray process (S110) to the electrode substrate 110 and the drying process (S111) by hot air are performed. Finally, it is wound around the hoop 20b (S112).

  In the present embodiment, the area of the punching hole 110a drilled in the electrode substrate 110 using the punching blade 25a is about 1 cm in diameter in each of the band-like regions I, II, and III regardless of the frequency of the punching process by the punching device 25. Of a certain size.

  Then, the electrode substrate 110 wound around the hoop 20b is cut and formed into a large plate in which a plurality of substrates having a predetermined shape similar to the positive electrode plate 11a can be collected in the subsequent manufacturing process. Further, after this, the rejected product that has been punched is screened out by comparison with the specified mass and removed from the production line. On the other hand, a positive plate active material layer that satisfies the specified mass is further coated with a positive electrode active material layer, and after rolling, cut into a positive electrode plate 11a (see FIG. 1B). Provided.

  On the other hand, a negative electrode plate 11b made of a paste obtained by adding a conductive agent and a binder to a fine powder of a hydrogen storage alloy by a conventionally known method, and coating and pressing on a metal porous plate (punching metal) is also produced. Keep it.

  Thereafter, according to a conventionally known method, the power generation element 11 is manufactured, the positive electrode current collector plate 16a is welded to the positive electrode plate 11a, and the negative electrode current collector plate 16b is welded to the negative electrode plate 11b. And this joined body is accommodated in the battery container 10, the external positive electrode terminal 12a and the positive electrode current collector plate 16a disposed at one end, the external negative electrode terminal 12b and the negative electrode current collector plate 16b disposed at the other end, and the others The positive electrode current collector plate 16a and the negative electrode current collector plate 16b are welded to each other. Then, the alkaline storage battery 1 of this embodiment is completed by inject | pouring electrolyte solution in the battery container 10. FIG.

According to this embodiment, the following operations and effects can be obtained.
(1) In the X-ray transmission inspection step (S103), the foreign matter on the electrode substrate 110 is detected online based on the size thereof, and further, in the chemical solution attaching step (S104), the battery A chemical solution containing a reagent that emits light in the presence of a metal (here, copper) to be detected as a minute metal foreign object Me that causes a short circuit is deposited online. For this reason, since the chemical solution can be intensively attached only to the portion where the foreign matter is easily detected, compared with the off-line inspection or the like that requires the chemical solution to be attached over the entire width direction of the electrode substrate 110. The amount of chemicals used can be reduced. For this reason, in the X-ray transmission inspection step (S103), by setting the inspection sensitivity to be high in order to reduce the inspection omission of the minute metal foreign material Me (see FIG. 3) that should be detected originally, Even when foreign matter is detected, detection of foreign matter such as nickel particles that should not be detected in the chemical solution attaching step (S104) can be eliminated. In other words, compared to the case where the detection sensitivity is set to a constant value and the foreign matter on the electrode substrate 110 is only detected in a single step based on the size, the inspection omission of the minute metallic foreign matter Me can be reduced. At the same time, it is possible to reduce erroneous detection that erroneously detects foreign matters other than the minute metal foreign matter Me. As a result, the minute metal foreign object Me can be selectively removed from the electrode substrate 110 with high accuracy.

  (2) In the X-ray transmission inspection step (S103), the electrode substrate 110 as an inspection object is irradiated with X-rays online and transmitted, and on the electrode substrate 110 based on the obtained X-ray transmission inspection signal. The part where the foreign object exists was specified. By using X-rays in this manner, visible light is not transmitted, and a portion where foreign matter is present can be identified efficiently even on the opaque electrode substrate 110. In addition, there is no possibility that the electrode substrate 110 is altered or damaged by the X-ray irradiation.

  (3) In the light emission portion detection step (S105), a portion emitted by the chemical solution using the image intensifier 24a, that is, a portion where the minute metal foreign material Me to be detected is detected is detected. A defective portion where Me is present can be identified with high sensitivity. As a result, the minute metal foreign matter Me can be selectively removed with higher accuracy.

  (4) Since the reagent used for the detection of the minute metal foreign matter Me is luminol, the minute metal foreign matter Me made of copper or copper alloy is used by utilizing the light emission phenomenon (chemiluminescence phenomenon) of luminol using copper or iron as a photocatalyst. It becomes possible to detect with good sensitivity. Moreover, since a chemical solution containing luminol as a reagent soaks well into a foamed nickel plate having a three-dimensional network structure, the luminol also emits copper or a copper alloy as the minute metallic foreign matter Me existing inside the electrode substrate 110. The phenomenon can be detected with good sensitivity.

  (5) In the electrode substrate 110, a chemical solution containing a reagent that emits light in the presence of a metal (here, copper) to be detected as the minute metal foreign material Me is contained in pure water as a solvent in a portion where the foreign material is detected. Since it is selectively attached, it is possible to reduce the amount of the chemical used compared with the case where the chemical is attached over the entire width direction of the electrode substrate 110.

  (6) Since the chemical solution used for detection of the minute metal foreign matter Me contains ammonia, the ammonia is coordinated to copper to form a water-soluble copper ammine complex, and the solubility of copper in the reagent which is an aqueous solution is increased. Enhanced. Thereby, the light emission phenomenon (photoluminescence phenomenon) of luminol using copper as a photocatalyst is promoted. Ammonia is a solvent having a low viscosity and has good permeability to the foamed nickel plate. As a result, the detection sensitivity of the fine metal foreign matter Me made of copper or copper alloy is further enhanced, and the fine metal foreign matter can be selectively removed with higher accuracy. In addition, since ammonia is a solvent that itself releases an —OH group, the chemical solution becomes alkaline, luminol is easily dissolved, and a luminol luminescence phenomenon can be caused in an alkaline aqueous solution. As a result, the amount of chemical substances used can be reduced. Further, since ammonia is almost completely volatilized at about 80 ° C., the electrode substrate 110 can be almost completely removed by drying with hot air, and environmental pollution caused by ammonia and health damage to workers can be effectively suppressed. . Furthermore, ammonia has the advantage that it is easily available, is inexpensive, and is suitable for industrial use in large quantities.

  (7) The electrode substrate 110 as an object to be inspected is divided into three rows (a plurality of rows) of belt-like regions I, II, and III arranged in parallel in the width direction, and a minute metal is online for each of the belt-like regions I, II, and III. The foreign object Me was inspected. As a result, the electrode substrate 110 is divided into three (plurality) in the width direction by the three rows (plurality) of strip-like regions I, II, and III, and foreign matter is inspected. That is, in the X-ray transmission inspection process (S103) as the primary screening process, foreign substances are detected for each of the band-like areas I, II, III, and each band-like area is detected in the chemical solution attaching process (S104). A chemical | medical solution will adhere within the range of I, II, and III. For this reason, compared with the case where the electrode substrate 110 is inspected simultaneously in the entire width direction and the chemical solution is adhered over the entire width direction, the chemical solution can be attached in a smaller area. The amount of usage will be further reduced.

  (8) In the defective portion removing step (S106), the defective portion of the electrode substrate 110 is removed by a punching process in which the electrode substrate 110 is punched in the thickness direction. For this reason, when the positive electrode plate 11a is collected by cutting the electrode substrate 110 into a strip shape, the mass of the positive electrode plate 11a in which the punching hole 110a is punched by the punching process is reduced from the specified mass. By measuring, it becomes possible to select the non-defective positive electrode plate 11a in which the minute metal foreign matter Me does not exist.

  (9) Depending on the frequency of the punching process, when the frequency is less than the specified value, the transfer speed of the electrode substrate 110 is increased, and when the frequency is greater than the specified value, the transfer speed of the electrode substrate 110 is decreased. Further, when the frequency is substantially equal to the specified value, the conveyance speed of the electrode substrate 110 is maintained. For this reason, the frequency of the punching process can be maintained at a substantially constant rate per time, and when the frequency of the punching process is high, the burden on various inspection devices and the punching device 25 is reduced, so that an inspection error can be prevented. In addition, when the frequency of the punching process is low, the production rate of the positive electrode plate 11a can be increased and the production efficiency thereof can be increased.

  (10) As a result, the positive electrode plate 11a can be formed (collected) from the electrode substrate 110 with high yield, leading to a reduction in manufacturing cost. Moreover, the obtained positive electrode plate 11a also has very little adhesion (mixing) of the minute metal foreign matter Me, and finally the alkaline storage battery 1 having high reliability can be obtained.

The above embodiment may be modified as follows.
-In the said embodiment, luminol was used as a reagent. However, the present invention is not limited to this, and other compounds such as lucigenin and lophine that produce strong green-blue chemiluminescence may be used as long as they produce a chemiluminescence phenomenon using copper as a photocatalyst. Nitrogen heterocyclic compounds can also be used.

  In the above embodiment, when the detected light emitting portion is selectively removed as a defective portion in which the minute metal foreign matter Me exists, the defective portion is removed by punching (punching). However, the present invention is not limited to this, and any other defective part removing method can be used as long as it is suitable for online removal. Further, the removal of the defective portion by punching can be performed off-line with respect to the large plate once it is cut and formed from the electrode substrate 110 as a raw material of the positive electrode plate 11a. Furthermore, it is also possible to simply perform marking that marks the vicinity of the defective portion of the electrode substrate 110 using ink or the like. According to this, since it is possible to easily determine where the electrode substrate 110 is a defective part in a later process, it is possible to eliminate the defective part in a process that is most convenient in production, including online removal. Become. Further, according to this, since the punching hole 110a (see FIG. 5) that hinders the process when the positive electrode active material layer is applied and formed online is not formed in the electrode substrate 110, the positive electrode active material is online. This is advantageous when applying a layer.

  In the above embodiment, the winding speed of the electrode substrate 110 around the hoop 20b (conveying speed of the electrode substrate 110) is set according to the frequency of the punching process performed by the punching device 25 when the frequency is smaller than the specified value. When the frequency is higher than a specified value, the winding speed is lowered, and when the frequency is substantially equal to the specified value, the winding speed is maintained. Specifically, as described above, the winding speed of the hoop 20a is changed by the on / off control according to the frequency of the punching process. However, the present invention is not limited to this, and the winding speed of the hoop 20a can be changed by PID control according to other control methods, for example, the frequency of punching processing. Further, as the control index, the occurrence frequency of the defective portion can be used instead of the frequency of the punching process.

  In the above embodiment, each inspection by the X-ray transmission inspection device 21, the chemical solution spraying device 22, the optical sensor device 24, and the punching device 25 is performed in three rows (a plurality of rows) in which the electrode substrates 110 as inspection objects are arranged in parallel in the width direction. The strips are divided into strip-like regions I, II, and III, and minute metallic foreign matters are inspected online for each of the strip-like regions I, II, and III. However, the present invention is not limited to this, and each of the inspections described above divides the electrode substrate 110 as an inspection object into two or four or more strip-shaped regions arranged in parallel in the width direction, and the minute metal foreign matter is online online for each strip-shaped region. You may comprise so that it may test | inspect. Moreover, it is not always essential to divide into such belt-like regions.

  In the above embodiment, the area of the punching hole 110a drilled in the electrode substrate 110 using the punching blade 25a in each of the belt-like regions I, II, and III is a constant size regardless of the frequency of the punching process by the punching device 25. did. However, the present invention is not limited to this, and the area of the punching hole 110a (the area of the electrode substrate 110) for removing the minute metal foreign matter Me can be increased when the frequency of the punching process is larger than the specified value. As a result, it is possible to remove even a minute metallic foreign matter that exceeds the detection limit of the fine metallic foreign matter inspection apparatus 2 that is considered to exist with high accuracy around the portion where the fine metallic foreign matter Me is detected. The reliability of the alkaline storage battery can be further improved.

Further, technical ideas that can be grasped from the above-described embodiments and modifications will be described below.
○ A method for removing minute metal foreign matter mixed in an electrode substrate on which a positive electrode plate disposed in an alkaline storage battery is formed,
A primary screening step in which the electrode substrate is an inspection object, and foreign matter on the electrode substrate is detected online based on the size of the electrode substrate;
A chemical solution attaching step for attaching a chemical solution containing a reagent that emits light in the presence of a metal to be detected as a foreign material to the portion where the foreign material is detected;
In the electrode substrate, a light emission part detection step of detecting a part emitted by the chemical solution;
And a defective portion removing step of selectively removing the detected light emitting portion as a defective portion in which the minute metal foreign matter exists.

According to this configuration, in the primary screening process, the foreign substance on the electrode substrate is detected online based on the size thereof, and further, the minute part that causes a short circuit of the battery in the chemical solution attaching process at the part where the foreign substance is detected. A chemical solution containing a reagent that emits light in the presence of a metal to be detected as a foreign metal is adhered. For this reason, in the primary screening process, even if foreign matter other than the fine metal foreign matter is detected by setting the inspection sensitivity high in order to reduce the inspection omission of the fine metallic foreign matter to be originally detected, the chemical solution attaching step Therefore, it is possible to eliminate detection of foreign matters that should not be detected. In other words, compared to the case where the inspection sensitivity is set to a constant value and the foreign substance on the electrode substrate is detected only in a single process based on its size, the inspection leakage of the minute metallic foreign substance can be reduced and It is also possible to reduce false detections that erroneously detect foreign objects other than metal foreign objects. This makes it possible to selectively remove the minute metal foreign matter from the electrode substrate with high accuracy. Moreover, in the electrode substrate, a chemical solution containing a solvent is selectively attached to the portion where the foreign material is detected, and a reagent that emits light in the presence of the metal to be detected as a fine metal foreign material is attached in the entire width direction of the electrode substrate. Compared with the case where the chemical solution is adhered over the whole area, the amount of the chemical solution used can be reduced. As a result, the positive electrode plate can be formed (collected) with a high yield from the electrode substrate, leading to a reduction in manufacturing cost.
A method for producing a positive electrode plate disposed in an alkaline storage battery, wherein foreign substances containing a metal that exists on an electrode substrate on which a positive electrode plate having a predetermined shape is formed and dissolves at a positive electrode potential and precipitates at a negative electrode potential A method for producing an electrode substrate, comprising using the method for removing a minute metal foreign matter according to the above technical idea in order to remove from a metal.

According to this configuration, by using the method for removing fine metal foreign matter, the adhesion of the fine metal foreign matter is small, and a positive electrode plate having high quality can be manufactured with high yield.
○ A method for producing an alkaline storage battery provided with a positive electrode plate, which removes foreign substances including metals that exist on the electrode substrate on which the positive electrode plate of a predetermined shape is formed and dissolve at the positive electrode potential and precipitate at the negative electrode potential. Therefore, a method for producing an alkaline storage battery, characterized in that the method for removing fine metal foreign matter according to the technical idea is used.

  According to this configuration, by using the method for removing fine metal foreign matter, the adhesion of the fine metal foreign matter to the positive electrode plate is small, and an alkaline storage battery having high reliability can be manufactured.

(A) is a whole block diagram of the alkaline storage battery which concerns on embodiment of this invention, (b) is a top view of the positive electrode plate which concerns on embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS The whole block diagram of the fine metal foreign material inspection apparatus used for the fine metal foreign material inspection process which concerns on embodiment of this invention. The schematic diagram which shows the state of the fine metal foreign material which exists in the foaming nickel board (electrode board | substrate) of a core material. (A)-(d) is explanatory drawing which shows the test | inspection sensitivity and test | inspection range of the micro metal foreign material inspection process which concern on embodiment of this invention. 1 is a partial detail view of a minute metal foreign matter inspection apparatus according to an embodiment of the present invention. The flowchart figure of the fine metal foreign material inspection process which concerns on embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Alkaline storage battery, 2 ... Minute metal foreign material inspection apparatus, 11a ... Positive electrode plate, 11b ... Negative electrode plate 20a, 20b ... Hoop, 21 ... X-ray transmission inspection apparatus, 22 ... Chemical solution spraying apparatus, 23 ... Dancer roll, 24 ... Light Sensor device, 24a ... Image intensifier, 25 ... Punching device, 110 ... Electrode substrate, I, II, III ... Band-like region, Me ... Fine metal foreign matter.

Claims (12)

A method for producing a positive electrode plate for an alkaline storage battery formed from an electrode substrate and disposed in an alkaline storage battery,
A primary screening step of detecting the foreign matter distributed on the electrode substrate online based on its size while transporting the electrode substrate as an inspection object;
A chemical solution adhesion step for depositing a chemical solution contained in a solvent online with a reagent that emits light in the presence of a metal to be detected as a minute metal foreign matter that causes a short circuit of the battery on the portion where the foreign material is detected;
In the electrode substrate, a light emitting part detecting step for detecting a part emitted by the chemical solution online;
A method for manufacturing a positive electrode plate for an alkaline storage battery, comprising: a defective portion removing step of selectively removing the detected light emitting portion as a defective portion in which a minute metal foreign matter exists. It is a manufacturing method of the positive electrode plate for alkaline storage batteries of Claim 1, Comprising:
The electrode substrate is a foamed nickel plate, the metal is copper, and the reagent is luminol, and the chemical solution containing the reagent further contains hydrogen peroxide in a state of containing an alkaline substance in a solvent and exhibiting alkalinity. The manufacturing method of the positive electrode plate for alkaline storage batteries containing this. It is a manufacturing method of the positive electrode plate for alkaline storage batteries of Claim 2,
The said chemical | medical solution is a manufacturing method of the positive electrode plate for alkaline storage batteries in which ammonia is contained so that the light emission phenomenon of luminol which uses copper as a photocatalyst may be accelerated | stimulated. It is a manufacturing method of the positive electrode plate for alkaline storage batteries according to claim 3,
The manufacturing method of the positive electrode plate for alkaline storage batteries in which the said chemical | medical solution contains 0.05 mass% or more and 1 mass% or less luminol with respect to a solvent. It is a manufacturing method of the positive electrode plate for alkaline storage batteries of Claim 3 or Claim 4,
The manufacturing method of the positive electrode plate for alkaline storage batteries in which the said chemical | medical solution contains 2 mass% or more and 4 mass% or less ammonia with respect to a solvent. It is a manufacturing method of the positive electrode plate for alkaline storage batteries as described in any one of Claims 1-5,
In the primary screening step, the electrode substrate as the inspection object is irradiated with X-rays on-line and transmitted, and a portion where foreign matter is detected on the electrode substrate is specified based on the obtained X-ray transmission image. X-ray transmission inspection process
In the light emission portion detection step, a method for producing a positive electrode plate for an alkaline storage battery, wherein an image intensifier is used to detect a portion emitted by the chemical solution. It is a manufacturing method of the positive electrode plate for alkaline storage batteries as described in any one of Claims 1-6,
A positive electrode plate for an alkaline storage battery in which the electrode substrate as the inspection object is divided into a plurality of rows of strip-shaped regions arranged in parallel in the width direction, and the foreign matter and the light-emitting portion are detected online for each strip-shaped region. Production method. It is a manufacturing method of the positive electrode plate for alkaline storage batteries as described in any one of Claims 1-7,
In the defective portion removing step, a method of manufacturing a positive electrode plate for an alkaline storage battery in which the defective portion is removed by a punching process in which the electrode substrate is punched in the thickness direction. It is a manufacturing method of the positive electrode plate for alkaline storage batteries according to claim 8,
Depending on the frequency of the punching process, when the frequency is less than a specified value, the speed at which the electrode substrate is transferred is increased, and when the frequency is higher than the specified value, the speed at which the electrode substrate is transferred is decreased. Further, when the frequency is substantially equal to a specified value, the method for manufacturing a positive electrode plate for an alkaline storage battery in which the speed at which the electrode substrate is conveyed is maintained. It is a manufacturing method of the positive electrode plate for alkaline storage batteries according to claim 8 or 9,
A method for manufacturing a positive electrode plate for an alkaline storage battery in which the area of the electrode substrate to be removed by the punching process is increased when the frequency of the punching process is larger than a specified value. A method for producing an alkaline storage battery in which a positive electrode plate, a negative electrode plate and an electrolytic solution are disposed,
The manufacturing method of the alkaline storage battery characterized by manufacturing the said positive electrode plate using the manufacturing method of the positive electrode plate for alkaline storage batteries as described in any one of Claims 1-10. A method for producing an alkaline storage battery having a positive electrode plate formed from an electrode substrate,
While transporting the electrode substrate as an inspection object, the electrode substrate is irradiated with X-rays on-line and transmitted, and a portion where foreign matter is detected on the electrode substrate is specified based on the obtained X-ray transmission image An X-ray transmission inspection process,
A chemical solution attaching step for attaching a chemical solution containing luminol contained in a solvent online in the presence of a metal to be detected as a minute metal foreign matter that causes a short circuit of the battery on the part where the foreign matter is detected;
In the electrode substrate, a light emitting part detecting step for detecting a part emitted by the chemical solution online;
A defective part removing step of selectively removing the detected light emitting part as a defective part in which a minute metal foreign matter exists.

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