DE102024102502A1 - Production plant for a coated film web and method for producing a coated film web - Google Patents

Abstract

The invention relates to a production plant (10) for a coated film web (12), comprising a production area (18) in which an uncoated film web (14) is provided with at least two coating strips (16), wherein the coating strips (16) run with their longitudinal direction parallel to the longitudinal direction of the film web (12) and with a lateral spacing parallel to one another, whereby an uncoated region (30) of the coated film web (12) is produced between the adjacent coating strips (16), and comprising a roller-shaped winding element (28), onto the outer surface (34) of which the coated film web (12) can be wound, wherein the winding element (28) is cambered, whereby the at least one uncoated region (30) of the coated film web (12) can be deposited on the winding element (28) without creases during winding.

Description

The invention relates to a production plant for a coated film web and a method for producing a coated film web.

The WO 2020/143971 A1 discloses a collector foil comprising a base material having an uncoated region and a strip-like coating region coated with a corresponding active material. The base material can have two strip-like coating regions adjacent to one another. An uncoated region of the base material comprises at least one stretch region, which is designed to mechanically decouple the at least one coating region from the uncoated region.

Furthermore, the CH 296160 A A process for the production of wound capacitors consisting of several metallized insulating strips is known. These are separated from a supply strip during winding production, eliminating the conductivity of the metal layer near the separation point.

The object of the present invention is to provide a solution by means of which creases can be particularly effectively avoided when winding up a film web having respective coated areas and respective uncoated areas.

This object is achieved according to the invention by the subject matter. Further possible embodiments of the invention are disclosed in the subclaims, the description, and the figures. Features, advantages, and possible embodiments presented in the description for one of the subject matter of the independent claims are to be regarded at least analogously as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the subclaims.

The invention relates to a production system for a coated film web. The production system comprises a production area in which an uncoated film web is provided with at least two coating strips. The film web can in particular be a copper foil, in particular with a thickness of four to eight micrometers. The coating strips run with their longitudinal direction parallel to the longitudinal direction of the film web and with a lateral spacing parallel to one another. This results in an uncoated region of the coated film web between the adjacent coating strips. The coating strips are applied to the same side of the film web. The production system further comprises a roller-shaped winding element, onto whose outer surface the coated film web can be wound. In particular, it is provided that the coated film web is wound onto the winding element after passing through the production area. The winding element is cambered, whereby the at least one uncoated region of the film web can be deposited on the winding element without creases during winding. The winding element is thus bulbous or spherical in design and thus has a larger outer radius in a central region than in the respective edge regions, based on the axial direction. The axial direction runs parallel to a central axis of the winding element. This central axis coincides with a rotational axis of the winding element during winding. The winding element is thus designed like a cylinder with a curved outer surface. In particular, the winding element is rotationally symmetrical. Winding the coated film web onto the winding element enables the film web to be transported particularly easily, particularly within the production facility. If the at least one uncoated region of the film web were to wrinkle during winding onto the winding element, this could cause errors or quality defects in the coated film web. The at least one uncoated region of the film web between the respective coating strips represents a mechanical weak point in the film web and can lead to necking of the film web when subjected to web tension. The constriction can lead to the formation of wrinkles in this at least one uncoated area. If the coated film web is wound onto the winding element in such a way that the wrinkles of the at least one uncoated area are not pulled smooth, these wrinkles can solidify in the coated area by being firmly embossed into the uncoated area during winding. Due to this wrinkling, web tears can occur more frequently during further processing of the coated film web during winding and unwinding during compression or during a cutting process, which makes the coated film web unprocessable. By providing the winding element with a specific thickening, the uncoated area of the film web can be which, in particular, borders two respective coating strips of the film web, can be pulled smooth, whereby higher web tensions can be generated in the uncoated area and wrinkles can thereby be smoothed out. The use of the cambered winding element makes it particularly easy to prevent wrinkles from forming in the at least one uncoated area during winding onto the winding element.

In a possible further development of the invention, it is provided that the winding element has, in a central region, a first radius relative to its central axis running in the axial direction, which is at least two millimeters and at most 15 millimeters, in particular at least seven millimeters and at most ten millimeters, greater than a second radius which the winding element has in an edge region. In this case, the edge region of the winding element is at a smaller distance from a respective nearest axial end of the winding element than the central region. With such a configuration of the winding element, creasing of the uncoated region of the film web can be reliably avoided, particularly in the case of a film web provided with two coating strips running parallel to one another.

In this context, it can be provided, in particular, that the winding element has the second radius at its respective outer ends with respect to the axial direction and the first radius in the center. In this case, the winding element is particularly mirror-symmetrical with respect to a plane that intersects the center axis of the winding element centrally and perpendicularly. This allows for a uniform smoothing of the uncoated area of the film web, which is located centrally in the case of two coating strips. This makes it particularly effective in preventing wrinkling in this uncoated area.

In a further possible embodiment of the invention, it is provided that the production plant comprises an unwinding element from which the uncoated film web can be unwound. Furthermore, it is provided that the production plant comprises a coating nozzle, in particular a slot nozzle, which is designed to apply the at least two coating strips parallel to the unwound film web at a lateral distance from one another. In particular, both the unwinding element and the coating nozzle are part of the production area of the production plant. The unwinding element enables the uncoated film web to be transported to the slot nozzle while wound up on this unwinding element. This enables particularly simple and compact transport of the uncoated film web to the coating nozzle. This makes it possible to keep the risk of damage to the film web during transport particularly low. By means of the coating nozzle, in particular the slot nozzle, the respective coating strips can be applied to the film web particularly easily with a continuous thickness.

In a further possible embodiment of the invention, the production plant comprises an oven by means of which the coating strips on the film web can be dried before winding onto the winding element. In particular, it is provided that the uncoated film web is provided with the at least two coating strips by means of the coating nozzle, and then the coated film web is passed through the oven, whereby the coating strips dry. After the coating strips have been dried by means of the oven, the coated film web is wound onto the winding element, whereby the coated film web can be stored particularly compactly and/or transported particularly easily.

In a further possible embodiment of the invention, it is provided that the production plant is configured to produce an electrode for a battery cell by coating the film web. The coated film web can thus comprise a film designed as a substrate carrier and an electrode paste as a coating strip. The electrode for the battery cell can thus be continuously manufactured by means of the production plant. This battery cell can be used in particular in a traction battery for a motor vehicle. This means that the battery cell can be configured to provide electrical energy for an electric drive train of the motor vehicle, whereby the motor vehicle can be driven by means of the electrical energy.

The invention further relates to a method for producing a coated film web, in which an uncoated film web is coated with at least two coating strips. The coating strips extend with their longitudinal direction parallel to the longitudinal direction of the film web and with a lateral spacing parallel to one another. This results in an uncoated region of the coated film web between the adjacent coating strips. The method further provides The coated film web is wound onto a lateral surface of a roll-shaped winding element, the winding element being cambered. This allows the at least one uncoated region of the film web to be deposited on the winding element without creases during winding. In particular, the winding element is roller-shaped and thus elongated with a round cross-section, the lateral surface being cambered. In particular, the lateral surface is convexly curved outwards.

In a possible further development of the invention, a copper foil is coated as a foil web. This copper foil can, in particular, have a thickness of four to eight micrometers. Because the foil web comprising the copper foil is wound up by means of the cambered winding element after coating, the imprinting of creases in the at least one uncoated area of the foil web during winding can be particularly effectively avoided. This allows for particularly good further processing of the coated foil web wound onto the winding element.

Further features of the invention may emerge from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features shown below in the description of the figures and/or in the figures alone, can be used not only in the respective combinations specified, but also in other combinations or on their own, without departing from the scope of the invention.

• 1 eine schematische Seitenansicht einer Herstellungsanlage für eine beschichtete Folienbahn;
• 2 eine Draufsicht auf die beschichtete Folienbahn;
• 3 einen schematischen Längsschnitt eines rollenförmigen Aufwickelelements; und
• 4 einen schematischen Querschnitt des Aufwickelelements gemäß 3.

The drawing shows:

• 1 a schematic side view of a production line for a coated film web;
• 2 a top view of the coated film web;
• 3 a schematic longitudinal section of a roll-shaped winding element; and
• 4 a schematic cross-section of the winding element according to 3 .

In the figures, identical and functionally identical elements are provided with the same reference numerals.

In 1 A production plant 10 for a coated film web 12 is shown. This means that by means of the production plant 10, an uncoated film web 14 is provided with a coating, in the present case in the form of two coating strips 16. For this purpose, the production plant 10 comprises a production area 18 in which the coating strips 16 are applied to the uncoated film web 14. As the film web 14, in particular a copper foil with a thickness of four to eight millimeters is provided with the coating strip 16. In this case, at least two coating strips 16 are applied to the uncoated film web 14 with their longitudinal direction parallel to the longitudinal direction of the film web 14 and with a lateral spacing and parallel to one another. 2 The coated film web 12 with the two parallel coating strips 16 is shown in a schematic plan view. In particular, the production system 10 is configured to produce an electrode for a battery cell by coating the uncoated film web 14 with an electrode paste.

The production plant 10 in this case comprises an unwinding element 22, a coating nozzle 24, which in this case is designed as a slotted nozzle, an oven 26 and a winding element 28. To produce the coated film web 12, the uncoated film web 14 is unwound from the unwinding element 22, guided to the coating nozzle 24, coated with the coating strips 16 by means of the coating nozzle 24 and then guided through the oven 26. The coating strips 16 are dried by means of the oven 26. After passing through the oven 26, the coated film web 12 is wound onto the winding element 28, whereby the coated film web 12 is particularly compact and can therefore be stored in a particularly space-saving manner or transported particularly easily.

As in 2 As can be seen, there is an uncoated area 30 of the coated film web 12 between the two coating strips 16. This uncoated area 30 represents a mechanical weak point of the coated film web 12 and, when subjected to web tension, can lead to a constriction of the film web 12 in the uncoated area 30. Due to this constriction in the uncoated area 30, the film web 12 can wrinkle in this uncoated area 30. In order to avoid these wrinkles being impressed in the uncoated area 30 when the coated film web 12 is wound onto the winding element 28, it is provided that the winding element 28, which is designed in the shape of a roll, is cambered. The winding element 28 is in 3 shown in a longitudinal section along the axially extending central axis 32 of the winding element 28. In 4 is the winding element element 28 in a cross-section which is perpendicular to the central axis 32. As in 3 As can be seen, the winding element 28 is in the present case sleeve-shaped, wherein the outer surface 34 of this sleeve is bulbous and thus curved outwards in a central region. In order to ensure that the winding element 28 is particularly lightweight, the winding element 28 is in this case hollow on the inside. The winding element 28 has, in a central region relative to its central axis 32 running in the axial direction, a first radius 36 which is at least two millimeters and at most 15 millimeters, in particular by at least seven millimeters and at most ten millimeters, larger than a second radius 38 which the winding element 28 has in an edge region. In the present case, the winding element 28 has the second radius 38 at its respective outer ends relative to the axial direction and the first radius 36 in the center.

The cambered design of the winding element 28 enables the uncoated region 30 to be pulled smooth when the coated film web 12 is wound onto the winding element 28 by introducing a higher web tension in the uncoated region 30 compared to the regions coated with the respective coating strips 16.

Overall, the invention demonstrates how a sleeve can be used to reduce wrinkles when winding multi-strip battery electrodes. The cambered winding element 28 can also be used to wind coated film webs 12 with more than two coating strips 16 with a particularly wrinkle-free finish.

List of reference symbols

10

manufacturing facility

12

coated film web

14

uncoated film web

16

coating strips

18

Manufacturing area

22

Unwinding element

24

Coating nozzle

26

Oven

28

winding element

30

uncoated area

32

central axis

34

lateral surface

36

first radius

38

second radius

QUOTES CONTAINED IN THE DESCRIPTION

This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2020/143971 A1 [0002]
• CH 296160 A [0003]

Claims (8)

A production plant (10) for a coated film web (12), comprising a production area (18) in which an uncoated film web (14) is provided with at least two coating strips (16), wherein the coating strips (16) run with their longitudinal direction of extension parallel to the longitudinal direction of the film web (12) and with a lateral spacing parallel to one another, whereby an uncoated region (30) of the coated film web (12) is produced between the adjacent coating strips (16), and comprising a roller-shaped winding element (28), onto the outer surface (34) of which the coated film web (12) can be wound, wherein the winding element (28) is cambered, whereby the at least one uncoated region (30) of the coated film web (12) can be laid down on the winding element (28) without creases during winding. Manufacturing plant (10) according to Claim 1 , characterized in that the winding element (28) has, in a central region, a first radius (36) with respect to its central axis (32) running in the axial direction, which is at least 2 millimeters and at most 15 millimeters, in particular at least 7 millimeters and at most 10 millimeters, larger than a second radius (38) which the winding element has in an edge region. Manufacturing plant (10) according to Claim 2 , characterized in that the winding element (28) has the second radius (38) at its respective outer ends with respect to the axial direction and the first radius (36) in the center. Manufacturing plant (10) according to one of the preceding claims, characterized in that an unwinding element (22) is provided, from which the uncoated film web (14) can be unwound, and a coating nozzle (24), in particular a slot nozzle, is provided, which is designed to apply the at least two coating strips (16) with a lateral distance from one another to the unwound film web (14). Production plant (10) according to one of the preceding claims, characterized in that the production plant (10) comprises an oven (26) by means of which the coating strips (16) on the film web (12) can be dried before winding onto the winding element (28). Manufacturing plant (10) according to one of the preceding claims, characterized in that the manufacturing plant (10) is designed to produce an electrode for a battery cell by coating the film web (14). Method for producing a coated film web (12), in which an uncoated film web (14) is coated with at least two coating strips (16), wherein the coating strips (16) run with their longitudinal direction parallel to the longitudinal direction of the film web (12) and with a lateral spacing parallel to one another, whereby an uncoated region (30) of the film web (12) is produced between the adjacent coating strips (16), and in which the coated film web (12) is wound up on a lateral surface (34) of a roll-shaped winding element (28), wherein the winding element (28) is cambered, whereby the at least one uncoated region (30) of the film web (12) can be laid down on the winding element (28) without creases during winding up. Procedure according to Claim 7 , characterized in that a copper foil is coated as a foil web (14).