Apparatus for producing dry electrode

Abstract

A dry electrode production apparatus is disclosed. A dry electrode production apparatus according to one embodiment of the present invention, which produces an electrode using a film made of a mixture in which an electrode active material, a conductive material, and a binder are dry-mixed without using a solvent, comprises: a pair of pressure rollers that rotate to pressurize the mixture for manufacturing the film; and a cutting member that contacts at least one of the pair of pressure rollers to cut a portion of the mixture.

Description

Technology Field

[0001] The present invention relates to a dry electrode production apparatus, and more specifically, to a dry electrode production apparatus capable of improving the edge quality of a film. Background Technology

[0002] Recently, interest in energy storage technology has been steadily increasing. As application fields expand to include energy for mobile phones, camcorders, laptop PCs, and even electric vehicles, efforts in the research and development of electrochemical devices are becoming increasingly concrete.

[0003] Electrochemical devices are the most 주목받는 field in this regard, and among them, the development of rechargeable secondary batteries is the focus of interest. Recently, active research and development on new electrode and battery designs is being conducted to improve capacity density and specific energy in the development of secondary batteries.

[0004] Among the secondary batteries currently in use, lithium secondary batteries developed in the early 1990s are gaining attention for their advantages of having a higher operating voltage and significantly higher energy density compared to conventional batteries such as Ni-MH, Ni-Cd, and lead-acid batteries that use aqueous electrolytes.

[0005] While expectations for these electrochemical devices are rising, further improvements—such as lowering resistance, increasing capacitance, and enhancing mechanical properties and productivity—are required to accompany the expansion and advancement of their applications. Under these circumstances, there is a demand for manufacturing methods with higher productivity for electrodes used in electrochemical devices.

[0006] Electrodes for electrochemical devices are typically formed by laminating an electrode active material layer, which is formed by binding an electrode active material and a conductive material used as needed with a binder, onto a current collector. Electrodes for electrochemical devices include coated electrodes manufactured by applying a coated electrode slurry containing an electrode active material, a binder, a conductive material, etc. onto a current collector and removing a solvent by heat, etc.

[0007] In these methods, energy is required to dry the polymer film or to remove the solvent from the slurry for the coating electrode, which increases costs and makes it difficult to improve productivity.

[0008] Therefore, a method for manufacturing electrodes dry without using a slurry for coating electrodes is being proposed. This is known as a technique for producing electrodes using a film produced by mixing an electrode active material, a binder, and a conductive material without a liquid medium such as a solvent or dispersion medium, and then passing the powder mixture through a rolling roll.

[0009] FIG. 1 is a perspective view of a pair of rolling rolls that pressurize a powder mixture to produce a conventional dry electrode, and FIG. 2 is a drawing showing a film produced by the rolling rolls of FIG. 1.

[0010] As shown in FIG. 1, a pair of rolling rolls (1) are all of a flat, general shape. When a powder mixture (2) mixed without a liquid medium is rolled using the pair of rolling rolls (1) of FIG. 1, as shown in FIG. 2, both ends (3) of the powder mixture (2) are formed irregularly and unevenly, causing problems such as film breakage and meandering.

[0011] In addition, there is a problem that the process time increases because the film cannot be formed continuously due to film breakage and meandering, and the worker must manually cut and remove the irregular parts of both ends (3) of the mixture (2). Prior art literature

[0012] Republic of Korea Published Patent Publication No. 10-2020-0017821 (Publication Date: February 19, 2020) The problem to be solved

[0013] Therefore, the technical problem to be solved by the present invention is to provide a dry electrode production device capable of automatically cutting a portion of a mixture to improve the edge quality of a film.

[0014] In addition, the invention provides a dry electrode production device capable of preventing film breakage and meandering.

[0015] In addition, the invention provides a dry electrode production device capable of reducing process time through continuous film formation. means of solving the problem

[0016] According to one aspect of the present invention, a dry electrode production apparatus for producing an electrode from a film made of a mixture in which an electrode active material, a conductive material, and a binder are dry-mixed without using a solvent may be provided, comprising: a pair of pressure rollers that rotate to pressurize the mixture for the production of the film; and a cutting member positioned on one of the pair of pressure rollers and cutting a portion of the mixture.

[0017] In addition, the cutting member may be configured to cut a portion of the mixture that is outside a preset range.

[0018] In addition, the above-mentioned pair of pressure rollers includes a first pressure roller and a second pressure roller, wherein the first pressure roller includes a roller body having a protrusion formed thereon for pressurizing the mixture; and a rotating shaft coupled to the roller body, and the cutting member may be provided in a pair and disposed at both ends of the protrusion.

[0019] In addition, the above pair of cutting members may be arranged to contact both ends of the protrusion and rotate in conjunction with the rotation of the roller body to cut the portion of the mixture that protrudes outward from the protrusion.

[0020] In addition, the pair of cutting members are spaced apart from both ends of the protrusion at a predetermined interval, and the pair of cutting members may be connected to a motor and rotated to cut the portion of the mixture that protrudes outward from the protrusion.

[0021] Additionally, the above-mentioned pair of pressure rollers includes a first pressure roller and a second pressure roller, wherein the first pressure roller comprises a roller body that pressurizes the mixture and has a pair of grooves formed at a preset interval; and a rotating shaft coupled to the roller body, and the cutting member may be provided in a pair and disposed in each of the pair of grooves.

[0022] In addition, the above pair of cutting members may be arranged to each contact the above pair of grooves and rotate in conjunction with the rotation of the roller body to cut the portion of the mixture located in the grooves.

[0023] In addition, the pair of cutting members are spaced apart from each of the pair of grooves at a predetermined interval, and the pair of cutting members may be connected to a motor and rotated to cut the portion of the mixture located in the groove.

[0024] And, the above cutting member can be made of plastic.

[0025] In addition, the cutting member may have a circular cross-section and a blade may be formed at the end. Effects of the invention

[0026] Embodiments of the present invention have the effect of automatically cutting a portion of the mixture to improve the edge quality of the film.

[0027] In addition, it has the effect of preventing film breakage and meandering.

[0028] In addition, continuous film formation has the effect of reducing process time. Brief explanation of the drawing

[0029] FIG. 1 is a perspective view of a pair of rolling rolls that pressurize a powder mixture to produce a conventional dry electrode. Figure 2 is a drawing showing a film produced by the rolling roll of Figure 1. FIG. 3 is a schematic overall perspective view of a dry electrode production device according to a first embodiment of the present invention. Fig. 4 is a side view of Fig. 3. Figure 5 is a drawing showing both ends of a mixture being cut by the dry electrode production device of Figure 3. FIG. 6 is a drawing showing a film produced by a dry electrode production device according to the first embodiment of the present invention. FIG. 7 is a schematic overall perspective view of a dry electrode production device according to a second embodiment of the present invention. Fig. 8 is a side view of Fig. 7. Figure 9 is a drawing showing both ends of a mixture being cut by the dry electrode production device of Figure 7. Specific details for implementing the invention

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely one preferred embodiment of the present invention and do not represent all aspects of the technical spirit of the present invention; therefore, it should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application.

[0031] In the drawings, the size of each component or specific part constituting the component is exaggerated, omitted, or schematically depicted for convenience and clarity of explanation. Accordingly, the size of each component does not entirely reflect its actual size. If it is determined that a detailed description of related known functions or configurations could unnecessarily obscure the essence of the invention, such description shall be omitted.

[0032] As used in this specification, the terms "combination" or "connection" include not only cases where one member and another member are directly joined or directly connected, but also cases where one member is indirectly joined or indirectly connected to another member through a connecting member.

[0033] The dry electrode production apparatus of the present specification relates to an apparatus for producing an electrode using a film (400) made of a mixture of powders (300, hereinafter referred to as the mixture) in which an electrode active material, a conductive material, and a binder are dry-mixed without using a solvent.

[0034] Here, the film (400) made from the powder mixture (300) means that the powder mixture (300) is produced in the form of a film (400) by dry-pressing the electrode active material, the conductive material, and the binder.

[0035] FIG. 3 is a schematic overall perspective view of a dry electrode production device according to a first embodiment of the present invention, FIG. 4 is a side view of FIG. 3, FIG. 5 is a drawing showing both ends of a mixture being cut by the dry electrode production device of FIG. 3, and FIG. 6 is a drawing showing a film produced by the dry electrode production device according to a first embodiment of the present invention.

[0036] Referring to the drawings, a dry electrode production device according to one embodiment of the present invention includes a pressure roller (100) and a cutting member (200).

[0037] The pressure roller (100) may be provided as a pair including a first pressure roller (110) and a second pressure roller (120). Referring to FIG. 5, the pair of pressure rollers (100) pressurize the mixture (300) while rotating for the manufacture of the film (400). Here, the first pressure roller (110) of the pair of pressure rollers (100) may be configured to include a roller body (111) and a rotation axis (115).

[0038] The roller body (111) is provided to pressurize the mixture (300). Referring to FIG. 3, a protrusion (112) may be formed on the roller body (111). And, a pair of cutting members (200), described later, are disposed at both ends of the protrusion (112).

[0039] Here, referring to FIG. 5, the mixture (300) is pressed by the protrusion (112) of the first pressure roller (110), and the portion extending outside the protrusion (112) is cut by the cutting member (200) described later.

[0040] Meanwhile, among the pair of pressure rollers (100), the second pressure roller (120) is also configured to include a roller body (121) and a rotation axis (125), but the roller body (121) of the second pressure roller (120) may be provided as a general roller in a flat shape without a protrusion formed thereon. However, it is not limited thereto, and a protrusion (not shown) may also be formed on the second pressure roller (120).

[0041] And, the rotation shaft (115) is coupled to the roller body (111), and the rotation shaft (125) is coupled to the roller body (121). The rotation shaft (115) or the rotation shaft (125) is configured to rotate by being coupled to various power sources, and the roller bodies (111, 121) each coupled to the rotation shaft (115, 125) rotate together with the rotation shaft (115, 125) according to the rotation of the rotation shaft (115, 125).

[0042] A cutting member (200) is positioned on the first pressure roller (110) of a pair of pressure rollers (100) and is configured to cut a portion of the mixture (300). Here, the cutting member (200) may be configured to cut a portion of the mixture (300) that is outside a preset range, for example, a portion of the mixture (300) that extends beyond both ends of the protrusion (112).

[0043] Referring to FIG. 2 regarding the prior art, when a mixture (2) of powders mixed in a dry manner is pressurized, both ends (3) are formed irregularly and unevenly. In the dry electrode production device according to the first embodiment of the present invention, as shown in FIG. 5, a cutting member (200) is positioned on the first pressure roller (110) among a pair of pressure rollers (100), and the cutting member (200) cuts the irregularly and uneven parts extending beyond both ends of the protrusion (112) in the mixture (300).

[0044] In this way, when the cutting member (200) cuts the irregular and uneven parts extending beyond both ends of the protrusion (112) in the mixture (300), the edge quality of the film (400) is improved as shown in FIG. 6.

[0045] Here, the way the cutting member (200) is positioned on the first pressure roller (110) of the pair of pressure rollers (100) can vary.

[0046] One embodiment is a method in which a cutting member (200) contacts a protrusion (112) as shown in FIG. 3. That is, a pair of cutting members (200) each contact both ends of the protrusion (112) and rotate in conjunction with the rotation of the roller body (111) to cut the portion of the mixture (300) that protrudes outward from the protrusion (112).

[0047] In the case of the above embodiment, the cutting member (200) receives the rotational force of the roller body (111) and rotates together with it, so a separate power source is not required.

[0048] And, another embodiment, although not shown in the drawing, is a method in which the cutting member (200) is spaced apart from the protrusion (112). That is, a pair of cutting members (200) are spaced apart from both ends of the protrusion (112) at a predetermined distance.

[0049] In this case, even if the roller body (111) rotates, the cutting member (200) is independent of the rotation of the roller body (111), so a pair of cutting members (200) are connected to a separate power source, for example, a motor (not shown), and rotate to cut the portion protruding outward from the protrusion (112) in the mixture (300).

[0050] In the other embodiment above, a separate power source is required for the cutting member (200), so the rotational speed of the cutting member (200) can be controlled differently from the rotational speed of the roller body (111), thereby strengthening the cutting force. Therefore, one of the two embodiments above can be selected as needed.

[0051] The cutting member (200) can be made of various materials, and, for example, can be made of plastic considering hardness or strength. However, the material of the cutting member (200) is not limited to plastic.

[0052] Here, the cutting member (200) may have a circular cross-section and a blade may be formed at the end. However, the blade of the cutting member (200) does not necessarily have to be sharp and is formed to be sharp enough to cut the mixture (300).

[0053] Hereinafter, the operation and effects of a dry electrode production device according to the first embodiment of the present invention will be described with reference to the drawings.

[0054] Referring to FIGS. 3 to 5, the pressure rollers (100) are provided in pairs, and the first pressure roller (110) among the pair of pressure rollers (100) is configured to include a roller body (111) and a rotation axis (115), and a protrusion (112) is formed on the roller body (111).

[0055] Also, the second pressure roller (120) of the pair of pressure rollers (100) is also configured to include a roller body (121) and a rotation axis (125), but the roller body (121) can be provided as a general roller in a flat shape without a protrusion formed thereon.

[0056] As shown in FIG. 5, when the first pressure roller (110) and the second pressure roller (120) rotate, the mixture (300) is pressurized, and the two ends (310) of the mixture (300) are formed irregularly and unevenly. Here, a cutting member (200) is positioned on the first pressure roller (110) of the pair of pressure rollers (100), and the cutting member (200) cuts the portion of the mixture (300) that extends beyond the two ends of the protrusion (112).

[0057] As a result, the edge quality of the film (400) is improved as shown in Fig. 6.

[0058] FIG. 7 is a schematic overall perspective view of a dry electrode production device according to a second embodiment of the present invention, FIG. 8 is a side view of FIG. 7, and FIG. 9 is a drawing showing both ends of a mixture being cut by the dry electrode production device of FIG. 7.

[0059] Hereinafter, a dry electrode production apparatus according to a second embodiment of the present invention will be described, provided that parts common to the dry electrode production apparatus according to the second embodiment of the present invention in the first embodiment described above are replaced by the description above. Furthermore, among the parts described in the second embodiment of the present invention, those applicable to the first embodiment may also be applied to the first embodiment.

[0060] The second embodiment of the present invention differs from the first embodiment in that a protrusion (112) is formed on the first pressure roller (110) in that a pair of grooves (113) are formed on the first pressure roller (110).

[0061] Referring to FIGS. 7 to 9, the first pressure roller (110) includes a roller body (111) and a rotation axis (115). Since the roller body (111) presses the mixture (300), this is common to the first embodiment and replaces the description above. Additionally, a pair of grooves (113) spaced apart at a predetermined interval are formed in the roller body (111). Here, a cutting member (200) is provided in a pair and is placed in each of the pair of grooves (113).

[0062] And, as described in the first embodiment, a pair of cutting members (200) may be arranged to each contact a pair of grooves (113) and rotate in conjunction with the rotation of the roller body (111) to cut the portion of the mixture (300) located in the grooves (113).

[0063] Alternatively, a pair of cutting members (200) may be spaced apart from each of the pair of grooves (113) at a predetermined interval, and the pair of cutting members (200) may be connected to a motor (not shown) and rotated to cut the portion of the mixture (300) located in the groove (113).

[0064] The rotation shaft (115) is coupled to the roller body (111) and is provided to rotate the roller body (111). However, the description regarding the rotation shaft (115) is replaced by the description given above in the first embodiment.

[0065] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0066] 100 : Pressure roller 110 : First pressure roller 111 : Roller body 112 : Protrusion 113 : Groove 115 : Rotation axis 120: Second pressure roller 121: Roller body 125 : Rotation axis 200 : Cutting member 300 : Mixture 400 : Film

Claims

Claim 1 A dry electrode production apparatus for producing an electrode using a film made of a mixture in which an electrode active material, a conductive material, and a binder are dry-mixed without using a solvent, the apparatus comprises: a pair of pressure rollers that rotate to pressurize the mixture for manufacturing the film; and a cutting member positioned on one of the pair of pressure rollers and cutting a portion of the mixture, wherein the cutting member cuts a portion of the mixture that is outside a preset range, wherein the pair of pressure rollers comprises a first pressure roller and a second pressure roller, wherein the first pressure roller comprises a roller body formed with a protrusion that pressurizes the mixture; and a rotating shaft coupled to the roller body, and wherein the cutting member is provided in a pair and disposed at both ends of the protrusion. Claim 2 delete Claim 3 delete Claim 4 A dry electrode production device according to claim 1, characterized in that the pair of cutting members contact both ends of the protrusion and rotate in conjunction with the rotation of the roller body to cut the portion of the mixture that protrudes outward from the protrusion. Claim 5 A dry electrode production device according to claim 1, wherein the pair of cutting members are spaced apart from both ends of the protrusion at a predetermined interval, and the pair of cutting members are connected to a motor and rotate to cut the portion of the mixture that protrudes outward from the protrusion. Claim 6 A dry electrode production apparatus for producing an electrode using a film made of a mixture in which an electrode active material, a conductive material, and a binder are dry-mixed without using a solvent, the apparatus comprises: a pair of pressure rollers that rotate to pressurize the mixture for manufacturing the film; and a cutting member positioned on one of the pair of pressure rollers and cutting a portion of the mixture, wherein the cutting member cuts a portion of the mixture that is outside a preset range, wherein the pair of pressure rollers comprises a first pressure roller and a second pressure roller, wherein the first pressure roller comprises a roller body that pressurizes the mixture and has a pair of grooves formed at a preset interval; and a rotating shaft coupled to the roller body, wherein the cutting member is provided in a pair and is disposed in each of the pair of grooves. Claim 7 A dry electrode production device according to claim 6, characterized in that the pair of cutting members each contact the pair of grooves and rotate in conjunction with the rotation of the roller body to cut the portion of the mixture located in the grooves. Claim 8 A dry electrode production device according to claim 1, wherein the pair of cutting members are spaced apart from each of the pair of groove portions by a preset interval, and the pair of cutting members are connected to a motor and rotate to cut the portion of the mixture located in the groove portion. Claim 9 A dry electrode production device characterized in that, in any one of claims 1 and 4 to 8, the cutting member is made of plastic. Claim 10 A dry electrode production device according to any one of claims 1 and 4 to 8, wherein the cutting member has a circular cross-section and a blade formed at the end.

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