JP6028628B2 - Electrode manufacturing equipment - Google Patents

Description

  The present invention relates to an electrode manufacturing apparatus.

  As an electrode manufacturing apparatus for manufacturing an electrode used in a power storage device, for example, a slurry containing an active material is attached to a coating roll, and the slurry attached to the coating roll is applied to a metal foil conveyed by a backing roll. Is known (see, for example, Patent Document 1). Moreover, the electrode manufacturing apparatus of patent document 1 is provided with the scraper which scrapes off the excess slurry adhering to the coating roll.

Japanese Patent No. 3483072

  Here, depending on the hardness of the scraper or the like, a part of the slurry may remain on the coating roll without being scraped off. In this case, the remaining slurry may be dried to become foreign matter, which may cause streaks and spots on the coating film of the slurry applied to the metal foil. Further, if the scraper has poor scraping properties, a solid active material or the like contained in the slurry may be sandwiched between the scraper and the coating roll, and the scraper or the coating roll may be scratched.

  This invention is made | formed in view of the situation mentioned above, and aims at providing the electrode manufacturing apparatus which can scrape off suitably the slurry adhering to a coating roll.

An electrode manufacturing apparatus that achieves the above object includes a coating roll in which a slurry region to which a slurry containing an active material adheres is continuously formed, and a backing roll that conveys a metal foil. The coating roll and the backing roll The slurry is intermittently applied to the metal foil by intermittently contacting the metal foil and the slurry while rotating the metal foil, with respect to the contact point between the metal foil and the slurry. The scraper is disposed on the downstream side in the rotation direction of the coating roll and scrapes off the slurry adhering to the coating roll, and the scraper is in the axial direction of the coating roll in the slurry region in the outer peripheral surface of the coating roll. Yes over from one end to the other end, in the scraper Contact portion between the serial coating roll is rubber, the durometer hardness of the rubber Ri 40-90 der, said scraper, axial end of the coating roll of the slurry region of the outer peripheral surface of the coating roll The first point is defined as the first point, and the second point is a point shifted from the first point at the other end opposite to the one end of the slurry region in the rotation direction of the coating roll. The slurry attached to the coating roll without being applied to the metal foil is provided with an arc portion that curves so as to be the same as the curvature along the outer peripheral surface of the coating roll that connects the second point. the scraper with the rotation of the coating roll reaches the position that is located, especially to be scraped off by the arc part of the scraper To.

  According to such a configuration, the durometer hardness of the rubber constituting the contact portion of the scraper is 40 to 90, so that the slurry containing the active material cannot be scraped off due to the contact portion being excessively soft. In addition, it is possible to avoid a situation in which the stick-slip phenomenon occurs due to the contact portion being excessively hard. Thereby, a slurry can be scraped off suitably.

Moreover, according to this structure, the slurry to be scraped off is intermittently adhered to the coating roll. In such a situation where the properties of the object to be scraped are uneven, a particularly high scraping property is required. On the other hand, by setting the hardness as described above, the slurry can be suitably scraped even when the property to be scraped is non-uniform.

Further, the scraper, according the axial end of the coating roll in the slurry area where the slurry is deposited out of the outer peripheral surface Oh Ru configuration over to the other end of the coating roll, adheres to the slurry area The slurry can be scraped off.

About the said electrode manufacturing apparatus, while the said arc part follows the outer peripheral surface of the said coating roll, a contact position with the said coating roll is the said coating roll as it goes to the other end in the axial direction of the said coating roll in the said slurry area | region. It is good to arrange so that it may shift in the direction of rotation. According to this structure, the slurry adhering to the slurry region moves along the arc portion and is collected. Thereby, while the force of the axial direction of a coating roll acts with respect to a slurry, slurry becomes easy to fall because slurry collects. Therefore, the slurry can be scraped off suitably.
About the said electrode manufacturing apparatus, it is good for the said 1st point and the said 2nd point to have shifted | deviated 180 degrees in the rotation direction of the said coating roll.

  About the said electrode manufacturing apparatus, it is good for the said arc part to extend from the end of the axial direction of the said coating roll in the said slurry area | region to the other end. According to such a configuration, the slurry can be scraped off more suitably as compared with a configuration in which the arc portion is provided only in a part of the slurry region from one end to the other end.

  According to this invention, the slurry adhering to the coating roll can be scraped off suitably.

The front view which shows an electrode manufacturing apparatus typically. (A) is a front view of a scraper, (b) is the 2b-2b sectional view taken on the line of (a). The perspective view of a coating roll and a scraper. The bottom view of a coating roll and a scraper. The figure which shows the relationship between the durometer hardness of a scraper, a streak, and a tab. (A) is a perspective view of the scraper of another example, (b) is a bottom view of the scraper and coating roll of another example. (A) is a perspective view of the scraper of another example, (b) is a bottom view of the scraper and coating roll of another example. (A) is a perspective view of the scraper of another example, (b) is a bottom view of the scraper and coating roll of another example.

  Hereinafter, an embodiment of an electrode manufacturing apparatus will be described below. The electrodes manufactured by the electrode manufacturing apparatus are stacked via a separator to form an electrode assembly. The electrode assembly is used for a secondary battery as a power storage device.

  As shown in FIG. 1, the electrode manufacturing apparatus 10 includes a supply roller 11 to which a wound strip-shaped metal foil M can be attached, and a take-up roller 12 capable of winding the metal foil M. Each of the rollers 11 and 12 is configured to be rotatable. The electrode manufacturing apparatus 10 rotates the rollers 11 and 12 in a state in which the wound metal foil M is attached to the supply roller 11 and one end in the longitudinal direction of the metal foil M is attached to the winding roller 12. As a result, the metal foil M is conveyed.

  The electrode manufacturing apparatus 10 includes an application unit 21 that applies a slurry S containing an active material, a conductive additive, a solvent, and the like to the metal foil M to be conveyed. The application unit 21 stores the slurry S on the outer circumferential surface 22 a of the cylindrical coating roll 22, stores the slurry S, supplies the slurry S to the outer circumferential surface 22 a of the coating roll 22, and a comma roll 24. And. The application unit 21 includes a columnar backing roll 25 that is provided near the coating roll 22 and conveys the metal foil M. The application unit 21 transfers the slurry S attached to the coating roll 22 to the metal foil M by contacting the slurry S and the metal foil M while rotating the coating roll 22 and the backing roll 25 in the same direction. A location where the slurry S and the metal foil M are in contact with each other is defined as a contact location A.

  Here, the backing roll 25 is configured so that the distance from the coating roll 22 can be adjusted, and the position where the slurry S and the metal foil M are in contact with the coating roll 22 can be transferred, It is configured to be movable between a position where the slurry S and the metal foil M are separated, which is a position where the transfer is impossible. The application unit 21 controls the position of the backing roll 25 to intermittently contact the slurry S with the slurry S and the metal foil M while rotating the coating roll 22 and the backing roll 25 in the same direction. Apply it.

  As shown in FIG. 1, the electrode manufacturing apparatus 10 includes a drying furnace 26 that dries the coating film of the slurry S applied by the application unit 21. The drying furnace 26 is disposed between the coating unit 21 and the winding roller 12. The metal foil M coated with the slurry S passes through the drying furnace 26 and is taken up by the take-up roller 12.

  The electrode manufacturing apparatus 10 includes a pressing device that presses the dried coating film, a cutting device that cuts the metal foil M into a predetermined electrode shape, and the like. The electrode manufacturing apparatus 10 manufactures an electrode having an active material layer by pressing the dried coating film and cutting the metal foil M.

  Here, a part of the slurry S adheres to the outer peripheral surface 22 a of the coating roll 22 without being transferred to the metal foil M. In particular, in the configuration in which the application unit 21 applies the slurry S intermittently, the slurry S is intermittently adhered to the outer peripheral surface 22 a of the coating roll 22.

  On the other hand, as shown in FIG. 1, the electrode manufacturing apparatus 10 is disposed on the downstream side in the rotation direction of the coating roll 22 with respect to the contact location A, and the slurry S adhering to the outer peripheral surface 22 a of the coating roll 22 is removed. A scraper 31 for scraping is provided. Moreover, the electrode manufacturing apparatus 10 includes a recovery tank 32 in which the slurry S scraped by the scraper 31 is recovered.

  As shown in FIGS. 2 and 3, the scraper 31 has a substantially flat plate shape. The scraper 31 includes a curved arc portion 41 on one end side in the short direction of the scraper 31. The arc portion 41 extends from one end of the scraper 31 in the longitudinal direction to the other end. The arc portion 41 is curved in a concave shape so that the length in the short direction of the scraper 31 gradually increases from the center in the longitudinal direction of the scraper 31 toward both ends. As shown in FIG. 2B, the arc portion 41 has a tapered shape having an inclined surface 41 a that is inclined with respect to the thickness direction of the scraper 31. In addition, the inclination angle θ of the inclined surface 41a is, for example, 13 °.

  Here, as shown in FIG. 3, a predetermined point at one end Za in the axial direction of the coating roll 22 of the slurry area Z to which the slurry S adheres on the outer peripheral surface 22a of the coating roll 22 is defined as the first point P1 and the slurry area. A point shifted from the first point P1 by 180 ° in the rotation direction of the coating roll 22 at the other end Zb opposite to the one end Za of Z is defined as a second point P2. The curvature of the arc portion 41 is the same as the curvature of an elliptical half-ridge along the outer peripheral surface 22a of the coating roll 22 that connects the first point P1 and the second point P2.

  As shown in FIGS. 3 and 4, the scraper 31 is disposed in a state where the longitudinal direction of the scraper 31 is inclined with respect to the axial direction of the coating roll 22. The scraper 31 and the arc portion 41 extend from one end Za to the other end Zb in the axial direction of the coating roll 22 in the slurry region Z. The arc portion 41 is inclined with respect to the rotation direction of the coating roll 22 in a bottom view, and is in contact with the outer peripheral surface 22 a of the coating roll 22. In this case, the contact position B between the arc portion 41 and the coating roll 22 is an arc shape connecting the first point P1 and the second point P2 corresponding to the shape of the arc portion 41, and the coating roll in the slurry region Z The coating roll 22 is displaced in the rotational direction as it extends from the one end Za in the axial direction of 22 toward the other end Zb.

  The scraper 31 is made of rubber, and its durometer hardness is 40 to 90, preferably 50 to 90, more preferably 60 to 90. The durometer hardness is measured by a method using a “durometer” based on “JIS K6253-3: 2012 vulcanized rubber and thermoplastic rubber—How to obtain hardness—Part 3: Durometer hardness” as a measuring instrument. Hardness. The durometer used for measurement in this embodiment is type A.

Next, the operation of this embodiment will be described.
The slurry S adhering to the coating roll 22 without being transferred to the metal foil M reaches the location where the scraper 31 is disposed as the coating roll 22 rotates, and is scraped off by the arc portion 41 of the scraper 31. . In this case, as shown in FIG. 4, the contact position B between the coating roll 22 and the arc portion 41 is shifted in the rotation direction of the coating roll 22 from the one end Za of the slurry region Z toward the other end Zb. The taken slurry S moves along the arc portion 41 toward the other end Zb of the slurry region Z. Then, the slurry S is collected on the other end Zb side of the slurry region Z and falls toward the collection tank 32 so as to drip from the other end Zb side.

  The relationship between the durometer hardness of the scraper 31 and streaks and tabs will be described with reference to FIG. FIG. 5 shows a case where a positive electrode slurry is applied to an area of 165 mm width × 130 mm length at intervals of 50 mm on the surface of an aluminum foil having a width of 185 mm × length 400 m as the metal foil M. It is the result of observing whether or not a tube exists. In FIG. 5, “◯” indicates that there are no streaks and tabs, “Δ” indicates that there are streaks and tabs having a width of less than 1 mm, and “x” tends to adversely affect the performance of the electrode. It indicates that there were streaks and protrusions with a width of 1 mm or more. Further, in consideration of manufacturing variations, five scrapers manufactured with the same specifications are prepared, and the results when each scraper is used are shown as Examples 1 to 5. In addition, the said conditions are an example and various dimensions, such as metal foil M, are not limited at all.

  As shown in FIG. 5, when the durometer hardness of the scraper 31 is less than 40 or greater than 90, streaks and tabs with a width of 1 mm or more are likely to occur, while the durometer hardness of the scraper 31 is 40 to 40 mm. In the case of 90, it was confirmed that streaks and protrusions having a width of 1 mm or more are less likely to occur. In particular, when the durometer hardness of the scraper 31 is 50 to 90, it has been confirmed that no streak or protrusion occurs.

  When the durometer hardness of the scraper 31 is less than 40, a part of the hard active material passes through the scraper 31 due to the softness of the scraper 31, and streaks and protrusions are generated. Conceivable.

  In addition, when the durometer hardness of the scraper 31 is greater than 90, a stick-slip phenomenon occurs between the scraper 31 and the coating roll 22, and wide stripes and protrusions are generated.

  Incidentally, when the durometer hardness of the scraper 31 is greater than 90, streaks and protrusions having a width of 1 mm or more are likely to occur suddenly. On the other hand, under the condition that the durometer hardness of the scraper 31 is less than 50, streaks and protrusions tend to occur gradually as the durometer hardness decreases. At this time, when the durometer hardness of the scraper 31 was 40, it was confirmed that the scraping property was secured to some extent in more than half of Examples 1 to 5.

According to the embodiment described in detail above, the following excellent effects are obtained.
(1) The scraper 31 is rubber, and its durometer hardness is 40 to 90, more preferably 50 to 90. Thereby, the slurry S adhering to the outer peripheral surface 22a of the coating roll 22 can be scraped off suitably.

  In particular, in the present embodiment, the object to be scraped off is a slurry S containing a solid active material and a conductive additive. In this case, when the slurry S is scraped off by the scraper 31, the active material or the conductive auxiliary agent is sandwiched between the scraper 31 and the coating roll 22, and as a result, the scraper 31 or the coating roll 22 may be scratched. On the other hand, by setting the durometer hardness of the scraper 31 to 40 to 90 as described above, the slurry S containing the active material or the like can be scraped suitably, and the generation of the scratch is suppressed. Can do.

  (2) The application unit 21 intermittently applies the slurry S to the metal foil M by bringing the metal foil M and the slurry S into contact with each other intermittently. In this case, the slurry S is intermittently adhered to the outer peripheral surface 22 a of the coating roll 22. When the properties of the object to be scraped off are not uniform, the slurry S is difficult to scrape off or is easily worn out. On the other hand, by setting the durometer hardness of the scraper 31 to 40 to 90 as described above, the slurry S can be suitably scraped even when the property of the object to be scraped is uneven. .

  (3) The scraper 31 extends from one end Za to the other end Zb in the axial direction of the coating roll 22 in the slurry region Z. Thereby, all the slurry S adhering to the slurry region Z can be scraped off.

  (4) The scraper 31 is located along the outer peripheral surface 22a of the coating roll 22, and the contact position B with the coating roll 22 is located at the coating roll 22 in the slurry region Z from the one end Za in the axial direction toward the other end Zb. The arc part 41 which shifts in the rotation direction of 22 is provided. Thereby, the slurry S adhering to the slurry region Z moves along the arc portion 41 and is collected. Thereby, the force in the axial direction of the coating roll 22 acts on the slurry S, and the slurry S easily falls due to the collection of the slurry S. Therefore, the slurry S can be suitably scraped off. Moreover, since the slurry S is collected, the range in which the slurry S falls becomes narrow. Thereby, collection | recovery of the slurry S can be performed easily.

  (5) Particularly, the arc portion 41 extends from one end Za to the other end Zb in the axial direction of the coating roll 22 in the slurry region Z. Thereby, compared with the structure which has an arc part in one part from the said one end Za to the said other end Zb, the slurry S can be scraped off more suitably.

In addition, you may change the said embodiment as follows.
In the embodiment, the scraper 31 includes the arc portion 41, and the scraper 31 is disposed in a state where the longitudinal direction of the scraper 31 is inclined with respect to the axial direction of the coating roll 22, but is not limited thereto. The scraper 31 may be a rectangular plate, and the scraper 31 may be arranged so that the longitudinal direction of the scraper 31 and the axial direction of the coating roll 22 are parallel to each other. Even if it is this structure, there exists an effect of (1) and (2) mentioned above by making the durometer hardness of the scraper 31 into 40-90. That is, if the durometer hardness of the scraper 31 is 40 to 90, the specific shape of the scraper 31 is arbitrary. Moreover, as long as the durometer hardness of the scraper 31 is in the range of 40 to 90, the range may be set in any way.

  As shown in FIGS. 6A and 6B, a scraper 51 having a V shape in plan view may be used. In this case, the scraper 51 includes a first arc portion 51 a in which the contact position B is shifted in the rotation direction of the coating roll 22 from the one end Za in the axial direction of the coating roll 22 in the slurry region Z toward the center. Further, the scraper 51 includes a second arc portion 51b in which the contact position B is shifted in the rotation direction of the coating roll 22 from the other end Zb in the axial direction of the coating roll 22 in the slurry region Z toward the center. The first arc part 51a and the second arc part 51b are continuous. According to such a configuration, the slurry S moves toward the intersection of the first arc portion 51a and the second arc portion 51b. Thereby, the slurry S can be collected suitably. In addition, as compared with the arc portion 41 of the embodiment, the space of the scraper 51 in the rotation direction of the coating roll 22 is reduced when the inclination angle of the arc portion with respect to the rotation direction of the coating roll 22 in the bottom view is the same. Therefore, the space of the scraper 51 can be reduced while the slurry S is scraped off suitably. The V-shaped scraper 51 may be arranged in such a manner that the center is upstream in the rotational direction and both ends are downstream in the rotational direction. Moreover, the 1st arc part 51a and the 2nd arc part 51b do not need to be continuous, for example, there may exist a linear part between the 1st arc part 51a and the 2nd arc part 51b.

  Further, as shown in FIGS. 7A and 7B, the scraper 61 may be curved in an arc shape in plan view. The scraper 61 also includes a first arc portion 61a and a second arc portion 61b. In this case, the maintenance for wiping off the slurry S adhering to the scraper 61 can be facilitated as much as there is no acute angle portion.

  Furthermore, as shown to Fig.8 (a) and FIG.8 (b), the scraper 71 which has the arc part 71a and the linear part 71b may be sufficient. In short, it is sufficient that at least a part of a portion of the scraper that contacts the coating roll 22 is an arc portion.

  In the embodiment, the scraper 31 exists from one end Za to the other end Zb of the slurry region Z, but is not limited to this, for example, exists from one end to the other end in the axial direction of the coating roll 22. May be.

  In the embodiment, the deviation angle between one end and the other end in the longitudinal direction of the arc portion 41 in the rotation direction of the coating roll 22 is 180 °, but is not limited thereto, and the deviation angle is arbitrary. In this case, since the inclination angle of the arc portion with respect to the rotation direction of the coating roll 22 increases as the deviation angle increases, the slurry S can be scraped off more suitably. On the other hand, as the deviation angle becomes smaller, the space of the scraper that occupies the rotation direction of the coating roll 22 can be reduced.

In the embodiment, the arc portion 41 has a tapered shape in which the thickness is gradually reduced. However, the shape is not limited to this, and the arc portion 41 may have a certain thickness.
In the embodiment, the entire scraper 31 is rubber. However, the present invention is not limited to this, and only the arc portion 41 that is a contact portion with the coating roll 22 may be rubber. In short, it is sufficient that at least the contact portion of the scraper with the coating roll 22 is rubber.

  In embodiment, although the application part 21 was the structure which apply | coats the slurry S intermittently, it is not restricted to this, The structure which apply | coats the slurry S continuously may be sufficient. Even in this case, the slurry S on the coating roll 22 can be scraped off by the scraper 31 without being transferred to the metal foil M.

Next, the technical idea that can be grasped from the above embodiment and other examples will be described below.
(A) The durometer hardness of the rubber is preferably 50 to 90.
(B) The arc portion has a first arc portion whose contact position is shifted in the rotation direction of the coating roll as it goes from one end in the axial direction of the coating roll in the slurry region to the center. It is good to have a 2nd arc part from which a contact position shifts to the rotation direction of a coating roll as it goes to the center from an end.

  (C) It has a coating roll to which a slurry containing an active material adheres and a backing roll that conveys the metal foil. By rotating the coating roll and the backing roll, the metal foil and the slurry are brought into contact with each other. In the electrode manufacturing apparatus for applying the slurry, the scraper is disposed on the downstream side in the rotation direction of the coating roll with respect to the contact point between the metal foil and the slurry, and scrapes off the slurry adhering to the coating roll. The coating roll extends from one end to the other end in the axial direction of the coating roll in the slurry region to which the slurry adheres, and the scraper extends along the outer peripheral surface of the coating roll and one end in the axial direction of the coating roll in the slurry region. Follow from the other direction The contact position between the coating roll may comprises an arc portion displaced in the direction of rotation of the coating roll. When paying attention to the technical idea, the durometer hardness of the scraper is not necessarily 40 to 90.

  DESCRIPTION OF SYMBOLS 10 ... Electrode manufacturing apparatus, 21 ... Application | coating part, 22 ... Coating roll, 22a ... Outer peripheral surface of coating roll, 25 ... Backing roll, 31 ... Scraper, 41 ... Arc part, 51, 61, 71 ... Scraper of another example, 51a , 61a ... first arc portion, 51b, 61b ... second arc portion, M ... metal foil, S ... slurry, Z ... slurry region.

Claims (4)

A coating roll in which a slurry region to which a slurry containing an active material adheres is continuously formed ;
Having a backing roll for conveying metal foil,
In the electrode manufacturing apparatus for intermittently applying the slurry to the metal foil by intermittently contacting the metal foil and the slurry while rotating the coating roll and the backing roll,
A scraper disposed on the downstream side in the rotation direction of the coating roll with respect to the contact point between the metal foil and the slurry, and scraping off the slurry adhering to the coating roll;
The scraper extends from one end to the other end in the axial direction of the coating roll in the slurry region of the outer peripheral surface of the coating roll,
The contact portion with the coating roll in the scraper is rubber,
Durometer hardness of the rubber Ri 40-90 der,
The scraper has a point at one end in the axial direction of the coating roll in the slurry region of the outer peripheral surface of the coating roll as a first point, and the first point at the other end opposite to one end of the slurry region. Is an arc portion that curves so as to have the same curvature along the outer peripheral surface of the coating roll connecting the first point and the second point when the point shifted in the rotation direction of the coating roll is the second point. With
Slurry adhering to the coating roll without being applied to the metal foil reaches a location where the scraper is disposed as the coating roll rotates, and is scraped off by the arc portion of the scraper. An electrode manufacturing apparatus. The arc part, with along the outer surface of the coating roll, so that the contact position between the coating roll toward the other end from the axial direction of the end of the coating roll in the slurry region is shifted in the direction of rotation of said coating roll The electrode manufacturing apparatus according to claim 1 , which is disposed in   The electrode manufacturing apparatus according to claim 1, wherein the first point and the second point are shifted by 180 ° in a rotation direction of the coating roll. The arc portion, the electrode manufacturing apparatus according to any one of claims 1 to 3 that is over the axial end of the coating roll in the slurry area to the other.