JP2012084310A - Electrode plate manufacturing apparatus and manufacturing method of battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode plate manufacturing apparatus capable of drying the front and rear surfaces of an electrode plate by the same dry profile, and provide a manufacturing method of a battery.SOLUTION: An electrode plate manufacturing apparatus 1000 includes a coat part 1200 and a dry furnace 1300. A first surface dry path 1700, a second surface dry path 1800, and pre-second surface coat conveyance paths 1900 and 1901 are provided in the dry furnace 1300. In addition, the first surface dry path 1700 for drying a paste layer of a first surface of an electrode core material and the second surface dry path 1800 for drying a paste layer of a second surface of the electrode core material are arranged in parallel.

Description

  The present invention relates to an electrode plate manufacturing apparatus and a battery manufacturing method. More specifically, the present invention relates to an electrode plate manufacturing apparatus and a battery manufacturing method for producing an electrode plate by coating both sides and drying.

  Batteries are used in various fields such as electronic devices such as mobile phones and personal computers, vehicles such as hybrid vehicles and electric vehicles. Such a battery includes a positive electrode plate, a negative electrode plate, and an electrolyte. Further, in order to insulate the positive electrode plate and the negative electrode plate, it is common to provide a separator between them.

  Generally, a battery is manufactured through various manufacturing processes. For example, in the manufacturing process of a lithium ion secondary battery, a coating liquid kneading step for kneading a coating liquid that becomes an electrode mixture layer (a positive electrode mixture layer and a negative electrode mixture layer) that causes an electrode reaction, and an electrode core material Electrode plate preparation step of applying electrode plate (positive electrode plate and negative electrode plate) by applying a coating liquid to (positive electrode core material and negative electrode core material), and a positive electrode plate and a negative electrode plate with a separator interposed therebetween In some cases, there are an electrode body preparation step of stacking and forming a stacked electrode body, and a battery assembly step of assembling a battery by inserting the stacked electrode body into the battery container and injecting an electrolyte.

  And when performing double-sided coating, like the technique of patent document 1, after coating on the 1st surface of an electrode core material, the paste layer coated on the 1st surface in the drying furnace Is dried, and after the coating on the second surface, the paste layer coated on the second surface is dried in a drying furnace (see paragraphs [0027]-[0028] and FIG. 1 of Patent Document 1).

JP-A-8-96800

  By the way, in the manufacturing process of the electrode plate of a lithium ion secondary battery, a difference arises in the performance of a battery by the drying profile which dries the paste applied to the electrode core material. For example, when the drying speed is increased, convection or the like occurs in the paste layer, and the binder contained in the paste moves. Also, solvent vapors that volatilize from the paste may push the binder to the top of the paste layer. As a result, binder migration causing segregation of the binder occurs, and the peel strength of the electrode plate may be low. When the peel strength of the electrode plate is low, the composite layer in which the electrode reaction occurs may peel from the electrode core material. An effective electrode reaction does not occur in the separated material layer. That is, the performance of the battery is low. Conversely, if the drying speed of the paste layer is slowed, the productivity of the electrode plate decreases.

  Moreover, in order to manufacture a battery having no variation in quality, it is preferable that the drying profiles of the first and second surfaces coated on both sides are the same. However, in the technique described in Patent Document 1, the drying profiles of the coating layers formed on the first surface and the second surface of the electrode core material are not the same. This is because the drying of the paste layer on the first surface and the drying of the paste layer on the second surface are performed in a separate drying furnace.

  The present invention has been made to solve the above-described problems of the prior art. That is, the problem is to provide an electrode plate manufacturing apparatus and a battery manufacturing method capable of drying the front and back surfaces of the electrode plate with the same drying profile.

  An electrode plate manufacturing apparatus according to an aspect of the present invention, which has been made for the purpose of solving this problem, is a first surface coating apparatus for applying a paste layer to a first surface of an electrode core material and a first electrode core material. A coating unit comprising a second surface coating device for coating a paste layer on two surfaces, and a drying furnace for transporting the electrode core material formed with the paste layer into the interior and drying the paste layer It has. And it has the front and back inversion part which reverses the 1st surface and 2nd surface of the electrode core material conveyed, and the 1st surface which dries the paste layer of the 1st surface of an electrode core material inside a drying furnace The drying path and the second surface drying path for drying the paste layer on the second surface of the electrode core material are arranged in parallel, and the front / back reversing part is downstream of the first surface drying path in the electrode core material conveyance path. And it is arrange | positioned in the position upstream from the coating apparatus for 2nd surfaces. Such an electrode plate manufacturing apparatus can dry the paste layer on the first surface of the electrode core material by the first surface drying path and the paste layer on the second surface of the electrode core material by the second surface drying path. Since the first surface drying path and the second surface drying path are arranged in parallel in the same drying furnace, the drying profile of the paste layer on the first surface of the electrode core material and the paste on the second surface of the electrode core material The drying profile of the layer is almost the same.

  In the electrode plate manufacturing apparatus described above, the electrode plate manufacturing apparatus has a second surface pre-coating conveyance path for conveying the electrode core material from the end of the first surface drying path to the second surface coating apparatus, and before the second surface coating. The conveyance path is provided inside the drying furnace, and the front / back reversing part is preferably provided in the middle of the conveyance path before the second surface coating. This is because the drying profile of the paste layer on the first surface of the electrode core material is almost the same as the drying profile of the paste layer on the second surface of the electrode core material. Even after the coating layer on the first surface is dried, the electrode core material is conveyed through the inside of the drying furnace, so that the solvent hardly adheres to the coating layer.

  In the electrode plate manufacturing apparatus described above, the electrode plate manufacturing apparatus has a second surface pre-coating conveyance path for conveying the electrode core material from the end of the first surface drying path to the second surface coating apparatus, and before the second surface coating. The conveyance path is provided outside the drying furnace, and the front / back reversing part may be provided in the middle of the conveyance path before the second surface coating. This is because the drying profile of the paste layer on the first surface of the electrode core material is almost the same as the drying profile of the paste layer on the second surface of the electrode core material. Moreover, since the conveyance path before the second surface coating is provided outside the drying furnace, the drying furnace can be reduced in size.

  In the electrode plate manufacturing apparatus described above, the distance from the first surface coating apparatus to the starting end of the first surface drying path and the distance from the second surface coating apparatus to the starting end of the second surface drying path The difference should be within 50 cm. This is because, in the case where the first surface is applied and the case where the second surface is applied, the time from the application of the paste to the start of drying can be made substantially the same.

  In the electrode plate manufacturing apparatus described above, at least one of the first surface coating apparatus and the second surface coating apparatus may be a coating die. This is because the coating of the first surface and the second surface of the electrode core material can be suitably performed.

  In the electrode plate manufacturing apparatus described above, at least one of the first surface coating apparatus and the second surface coating apparatus may be a gravure roll. This is because there is no change in that the first surface and the second surface of the electrode core material can be suitably applied.

  In another embodiment of the present invention, a battery manufacturing method includes applying a coating liquid to an electrode core material to form a paste layer, and transporting the inside of a drying furnace to dry the paste layer to form a positive electrode plate or a negative electrode An electrode plate forming step, a positive electrode plate and a negative electrode plate are laminated with a separator interposed therebetween to form a laminated electrode body, and the laminated electrode body is disposed inside the battery container And a battery assembling step of injecting an electrolyte into the battery container and sealing it. Further, in the electrode plate creation step, a first surface drying path for drying the paste layer on the first surface of the electrode core material and a second surface for drying the paste layer on the second surface of the electrode core material inside the drying furnace. An electrode plate manufacturing apparatus in which the drying path is arranged in parallel is used. Then, a coating liquid is applied to the first surface of the electrode core material to form a first paste layer, and the first paste layer is dried by a first surface drying path, and the first surface and the second surface of the electrode core material are then dried. After reversing the surface, a coating liquid is applied to the second surface of the electrode core material to form a second paste layer, and the second paste layer is dried by a second surface drying path. This is because, in such a battery manufacturing method, the drying profile of the paste layer on the first surface and the drying profile of the paste layer on the second surface can be made substantially the same in the electrode plate forming step. Therefore, there is almost no variation in the performance of the manufactured battery.

  In the battery manufacturing method described above, in the electrode plate preparation step, the direction in which the electrode core material coated with the first surface is conveyed into the drying furnace and the electrode core material coated with the second surface are disposed in the drying furnace. It is preferable that the direction of transporting is the same. This is because the drying profile of the paste layer on the first surface and the drying profile of the paste layer on the second surface can be made substantially the same in the electrode plate creation process.

  In the battery manufacturing method described above, in the electrode plate forming step, at least one of the first surface and the second surface of the electrode core material may be applied using a coating die. This is because the coating of the first surface and the second surface of the electrode core material can be suitably performed.

  In the battery manufacturing method described above, in the electrode plate creation step, at least one of the first surface and the second surface of the electrode core material may be applied using a gravure roll. This is because there is no change in that the first surface and the second surface of the electrode core material can be suitably applied.

  ADVANTAGE OF THE INVENTION According to this invention, the electrode plate manufacturing apparatus and battery manufacturing method which can be made to dry with the same drying profile about the front and back of an electrode plate are provided.

It is sectional drawing for demonstrating the structure of the battery which concerns on embodiment. It is a perspective view for demonstrating the winding electrode body of the battery which concerns on embodiment. It is an expanded view for demonstrating the winding structure of the winding electrode body in the battery which concerns on embodiment. It is a perspective sectional view showing the structure of the positive electrode plate (negative electrode plate) of the battery according to the embodiment. It is a perspective sectional view showing the structure of the positive electrode plate (negative electrode plate) manufactured by the electrode plate manufacturing apparatus according to the embodiment. It is a front view which shows schematic structure of the electrode plate manufacturing apparatus which concerns on embodiment. It is a top view which shows schematic structure of the electrode plate manufacturing apparatus which concerns on embodiment. It is a perspective view for demonstrating the front-back inversion apparatus of the electrode plate manufacturing apparatus which concerns on embodiment. It is a figure for demonstrating the conveyance path | route of the electrode core material in the electrode plate manufacturing apparatus which concerns on embodiment. It is a schematic block diagram for demonstrating the winding apparatus used for the manufacturing method of the battery which concerns on embodiment. It is a front view which shows schematic structure of another electrode plate manufacturing apparatus which concerns on embodiment.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below in detail with reference to the accompanying drawings. In the present embodiment, the present invention is embodied in an electrode plate manufacturing apparatus and a battery manufacturing method for manufacturing an electrode plate of a lithium ion secondary battery.

1. Battery The battery according to the present embodiment is a cylindrical lithium ion secondary battery. FIG. 1 shows a cross-sectional view of the battery 10 of the present embodiment. As shown in FIG. 1, the battery 10 is a battery cell sealed by a battery case including a battery container 11 and a lid 12. The battery 10 includes a wound electrode body 100, a positive current collector 110, and a negative current collector 120. In addition, an electrolytic solution is injected into the battery container 11.

  The wound electrode body 100 repeats charging and discharging in the electrolytic solution and directly contributes to power generation. The positive electrode current collector plate 110 is a positive electrode current collector connected to a positive electrode core material of a wound electrode body 100 described later. The material is aluminum. The negative electrode current collector plate 120 is a negative electrode current collector connected to a negative electrode core material of a wound electrode body 100 described later. Its material is copper.

  FIG. 2 shows a wound electrode body 100 of the wound electrode body battery according to this embodiment. As shown in FIG. 2, the wound electrode body 100 is a laminated electrode body in which a positive electrode plate and a negative electrode plate are wound around an axis 101 and separators S and T are interposed therebetween. The shaft core 101 is a member that becomes the center when the wound electrode body 100 is wound. Its shape is cylindrical. The outer diameter of the shaft core 101 is about 3 to 20 mm. However, other outer diameters may be used. Examples of the material include polyphenylene sulfide (PPS). In FIG. 2, a positive electrode non-coated portion P2 and a negative electrode non-coated portion N2 described later appear.

  The separators S and T are porous films such as polyethylene and polypropylene. The thicknesses of the separators S and T are about 10 to 50 μm. Here, the separator S and the separator T are made of the same material. For the understanding of the above winding order, only the codes are distinguished as S and T.

The electrolyte injected into the battery container 11 is obtained by dissolving an electrolyte in an organic solvent. Examples of organic solvents include ester solvents such as propylene carbonate (PC), ethylene carbonate (EC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC), ester solvents such as γ-butylactone (γ-BL), di- An organic solvent containing an ether solvent such as ethoxyethane (DEE) can be used. In addition, lithium salts such as lithium perchlorate (LiClO ₄ ), lithium borofluoride (LiBF ₄ ), and lithium hexafluorophosphate (LiPF ₆ ) can be used as the electrolyte salt.

  FIG. 3 is a development view showing a wound structure of the wound electrode body 100. As shown in FIG. 3, the wound electrode body 100 is wound in a state where the positive electrode plate P, the separator S, the negative electrode plate N, and the separator T are stacked in this order from the inside.

The positive electrode plate P is obtained by applying a composite material containing a positive electrode active material capable of inserting and extracting lithium ions to an aluminum foil as a positive electrode core material. As the positive electrode active material, lithium composite oxides such as lithium nickelate (LiNiO ₂ ), lithium manganate (LiMnO ₂ ), and lithium cobaltate (LiCoO ₂ ) are used. The negative electrode plate N is obtained by applying a composite material containing a negative electrode active material capable of occluding and releasing lithium ions to a copper foil as a negative electrode core material. As the negative electrode active material, carbon-based materials such as amorphous carbon, non-graphitizable carbon, graphitizable carbon, and graphite are used.

  As shown in FIG. 3, the positive electrode plate P has a positive electrode coating portion P1 and a positive electrode non-coating portion P2. The positive electrode coating part P1 is a place where a positive electrode mixture layer containing a positive electrode active material or the like is formed on a positive electrode core material. The positive electrode non-coated portion P2 is a portion where the positive electrode mixture layer is not formed on the positive electrode core material. The negative electrode plate N includes a negative electrode coating portion N1 and a negative electrode non-coating portion N2. The negative electrode coating portion N1 is a portion where a negative electrode mixture layer containing a negative electrode active material or the like is formed on a negative electrode core material. The negative electrode non-coated portion N2 is a portion where the negative electrode mixture layer is not formed on the negative electrode core material.

  An arrow A in FIG. 3 indicates the width direction (vertical direction in FIG. 2) of the positive electrode plate P, the negative electrode plate N, and the separators S and T. An arrow B in FIG. 3 indicates the longitudinal direction of the positive electrode plate P, the negative electrode plate N, and the separators S and T (the circumferential direction of the wound electrode body 100 in FIG. 2).

  FIG. 4 is a perspective sectional view of the positive electrode plate P (or the negative electrode plate N). In FIG. 4, each symbol outside the parentheses indicates each part in the case of the positive electrode, and each symbol in the parenthesis indicates each part in the case of the negative electrode. The direction indicated by arrow A in FIG. 4 is the same as the direction indicated by arrow A in FIG. That is, it is the width direction of the positive electrode plate P. The direction indicated by arrow B in FIG. 4 is the same as the direction indicated by arrow B in FIG. That is, it is the longitudinal direction of the positive electrode plate P.

  As shown in FIG. 4, the positive electrode plate P is obtained by forming a positive electrode mixture layer PA on a part of both surfaces of a strip-like positive electrode core material PB. On the left side in FIG. 4, a positive electrode non-coated portion P2 of the positive electrode plate P protrudes in the width direction. The positive electrode non-coated portion P2 is formed in a strip shape. The positive electrode non-coated portion P2 is a region where the positive electrode active material is not applied to both surfaces of the positive electrode core material PB. Therefore, in the positive electrode non-coating portion P2, the positive electrode core material PB is still exposed. On the other hand, on the right side in FIG. 4, there is no protrusion corresponding to the positive electrode non-coated portion P2. In the positive electrode coating part P1, the positive electrode mixture layer PA is formed with a uniform thickness on both surfaces of the positive electrode core material PB.

  The negative electrode plate N is obtained by forming a negative electrode mixture layer NA on a part of both surfaces of a strip-shaped negative electrode core material NB, as indicated by reference numerals in parentheses in FIG. Similarly to the positive electrode, there are a negative electrode coating portion N1 and a negative electrode non-coating portion N2. However, as shown in FIG. 3, at the time of winding, the positive electrode non-coated portion P2 and the negative electrode non-coated portion N2 are wound in a state of protruding to the opposite side.

2. Electrode plate manufacturing apparatus The electrode plate manufacturing apparatus of this embodiment will be described. The electrode plate manufacturing apparatus 1000 of this embodiment is for manufacturing the positive electrode plate PX or the negative electrode plate NX shown in FIG. By slitting the positive electrode plate PX and the negative electrode plate NX along the line L, the positive electrode plate P and the negative electrode plate N shown in FIG.

  The electrode plate manufacturing apparatus 1000 of this embodiment is for manufacturing the positive electrode plate PX and the negative electrode plate NX as described above. The production method of the negative electrode plate NX is the same as that of the positive electrode plate PX except that the core material and the coating liquid used are different. Therefore, the following description will be made assuming that the positive electrode plate PX is manufactured as a representative. A schematic configuration of the electrode plate manufacturing apparatus 1000 of the present embodiment is shown in a front view of FIG. 6 and a plan view of FIG. The electrode plate manufacturing apparatus 1000 includes an unwinding unit 1100, a coating unit 1200, a drying furnace 1300, a folding unit 1400, and a winding unit 1500.

  The unwinding unit 1100 has a unwinding reel 1101. The unwinding reel 1101 is for unwinding uncoated foil, that is, the positive electrode core material PB.

2-1. Coating part As shown in FIG. 7, the coating part 1200 can be applied to the positive electrode core PB at two locations. The coating unit 1200 includes a first surface coating die 1211, a second surface coating die 1221, and backup rollers 1212 and 1222. The first surface coating die 1211 is a first surface coating device for applying a paste layer to the first surface of the positive electrode core material PB. The backup roller 1212 conveys the positive electrode core material PB and supports the positive electrode core material PB when the first surface coating die 1211 applies the first surface of the positive electrode core material PB. The second surface coating die 1221 is a second surface coating device for applying a paste layer to the second surface of the positive electrode core material PB. The backup roller 1222 is for conveying the positive electrode core material PB and supporting the positive electrode core material PB when the second surface coating die 1221 applies the second surface of the positive electrode core material PB.

2-2. Drying oven The drying oven 1300 is for conveying the positive electrode core material PB on which the paste layer is formed to the inside thereof and drying the paste layer. The drying furnace 1300 is a three-stage drying furnace in which three furnaces are connected in series in the conveying direction of the positive electrode core material PB. That is, the drying furnace 1300 includes a first drying furnace 1310, a second drying furnace 1320, and a third drying furnace 1330. Further, inside the drying furnace 1300, a first surface drying path 1700, a second surface drying path 1800, and second surface pre-coating transport paths 1900 and 1901 are provided.

  The first surface drying path 1700 is a path for drying the paste layer applied to the first surface of the positive electrode core material PB. The first surface drying path 1700 is provided from the first drying furnace 1310 to the third drying furnace 1330. That is, the start end 1701 of the first surface drying path 1700 is an entrance of the drying furnace 1300 when the positive electrode core material PB is conveyed from the coating unit 1200 to the drying furnace 1300. A terminal end 1702 of the first surface drying path 1700 is an outlet for conveying the positive electrode core material PB from the drying furnace 1300 to the folded portion 1400.

  The second surface drying path 1800 is a path for drying the paste layer applied to the second surface of the positive electrode core material PB. The second surface drying path 1800 is provided from the first drying furnace 1310 to the third drying furnace 1330. That is, the start end 1801 of the second surface drying path 1800 is an entrance of the drying furnace 1300 when the positive electrode core material PB is conveyed from the coating unit 1200 to the drying furnace 1300. A terminal end 1802 of the second surface drying path 1800 is an outlet that conveys the positive electrode core material PB from the drying furnace 1300 to the folded portion 1400.

  The transport paths 1900 and 1901 before the second surface coating are for transporting the positive electrode core material PB whose first surface has been dried from the end 1702 of the first surface drying path 1700 to the location of the second surface coating die 1221. This is the route. The second surface pre-coating transport path 1900 is a path for transporting the positive electrode core material PB from the folded portion 1400 to the coating unit 1200. The conveyance path 1901 before the second surface coating is a path for changing the conveyance direction of the positive electrode core material PB at the turn-back portion 1400.

  The first drying furnace 1310, the second drying furnace 1320, and the third drying furnace 1330 each have an air nozzle 1301 and a roller 1302, as shown in FIG. The air nozzle 1301 is a nozzle for blowing hot air on the undried paste layer. The undried paste layer applied to the positive electrode core material PB is dried by hot air blown from the air nozzle 1301. The temperature, wind speed, and air volume of the hot air blown from the air nozzle 1301 are common in each of the first drying furnace 1310, the second drying furnace 1320, and the third drying furnace 1330. The roller 1302 is a free roller for conveying the positive electrode core material PB. In FIG. 7, the air nozzle 1301 and the roller 1302 are omitted.

  The in-furnace temperatures (atmosphere temperatures) of the first drying furnace 1310, the second drying furnace 1320, and the third drying furnace 1330 may be different temperatures. This is because the positive electrode paste is dried based on a drying profile suitable for drying the positive electrode paste by zone drying. Of these, the temperature in the first drying furnace 1310 is the lowest. The furnace temperature of the third drying furnace 1330 is the highest. This is to gradually dry the applied paste.

  Here, the first surface drying path 1700, the second surface drying path 1800, and the second surface pre-coating transport path 1900 are all provided over the first drying furnace 1310, the second drying furnace 1320, and the third drying furnace 1330. ing. The first surface drying path 1700 and the second surface drying path 1800 are arranged in parallel. Further, the transport direction and transport speed of the positive electrode core material PB in the second surface drying path 1800 are the same as those in the first surface drying path 1700.

  And the paste layer of the 1st surface is conveyed in the inside of the 1st drying furnace 1310, the 2nd drying furnace 1320, and the 3rd drying furnace 1330 in this order. The paste layer on the second surface is conveyed in this order in the first drying furnace 1310, the second drying furnace 1320, and the third drying furnace 1330. Therefore, the paste layer on the first surface and the paste layer on the second surface are dried with the same drying profile.

  Here, the drying profile is the time change of the temperature of the paste followed until the undried paste layer is dried. In this embodiment, the atmospheric temperature, the wind speed, the air volume, the temperature of the hot air, etc. inside the drying furnace 1300 are common when the paste layers on the first surface and the second surface of the positive electrode core material PB are dried.

2-3. Front / Back Reversing Device Also, a front / back reversing device 1600 is provided inside the second drying furnace 1320. Further, the position where the front / back reversing device 1600 is provided is in the middle of the conveyance path 1900 before the second surface coating. That is, the front / back reversing device 1600 is disposed at a position downstream of the first surface drying path 1700 and upstream of the second surface coating die 1221 in the transport path of the positive electrode core material PB. The front / back reversing device 1600 is a front / back reversing unit that reverses the first surface and the second surface without contacting the conveyed positive electrode core PB. As shown in FIG. 8, the front / back reversing device 1600 includes a first reversing member 1610, a second reversing member 1620, and a third reversing member 1630. In FIG. 8, the first surface of the positive electrode core material PB is hatched with a slash and the second surface is hatched with a dot.

  The first reversing member 1610 is a member having a semicircular or semi-elliptical cross-sectional shape. Air is ejected from the semicircular or semi-elliptical portion. Therefore, the conveyed positive electrode core PB does not contact the first reversing member 1610. The second reversing member 1620 is a cylindrical member. Air is ejected from the columnar portion of the second reversing member 1620. Therefore, the conveyed positive electrode core PB does not contact the second reversing member 1620. The third reversing member 1630 is a member having a semicircular or semi-elliptical cross-sectional shape. Air is ejected from the semicircular or semi-elliptical portion. Therefore, the conveyed positive electrode core material does not contact the third reversing member 1630.

  In the folding portion 1400, the positive electrode core material PB coated and dried on the first surface is conveyed toward the second surface coating die 1221. That is, the positive electrode core material PB is transported from the first surface drying path 1700 to the second surface pre-coating transport path 1900. Further, the positive electrode core material PB coated and dried on the second surface is conveyed to the winding unit 1500. The folding unit 1400 includes folding rollers 1401 and 1402. The folding roller 1401 is for changing the traveling direction of the positive electrode core material PB dried from the paste layer on the first surface to the direction of the arrow I3 in FIG. The folding roller 1402 is for changing the positive electrode core material PB to the direction of the arrow I4 in FIG.

  The winding unit 1500 has a winding reel 1501. The take-up reel 1501 is for taking up the positive electrode plate PX.

  As described above, the positive electrode is representatively described, but the same applies to the negative electrode. Thus, in the electrode plate manufacturing apparatus 1000 of this embodiment, the first surface and the second surface of the electrode core material can be dried with the same drying profile. This is because the inside of the same drying furnace is transported at the same speed. Further, since the drying furnace for drying the first surface and the drying furnace for drying the second surface are common, it is necessary to provide a drying furnace for drying the first surface and a drying furnace for drying the second surface separately. Absent. That is, it is possible to reduce the size of the drying furnace.

3. Next, how the electrode core material is conveyed inside the drying furnace will be described. The electrode core conveying path will be described with reference to FIGS. In FIG. 9, the first surface of the positive electrode core material PB is drawn with slashes and the second surface is hatched with dots. Further, the positive electrode core material PB will be described as an example.

  The positive electrode core material PB is unwound from the electrode foil reel 1101 of the unwinding portion 1100. The unwound positive electrode core material PB is conveyed in the direction of the first surface coating die 1211 in the direction of the arrow I1 in FIG. Subsequently, the positive electrode core material PB is coated on the first surface with a first surface coating die 1211. Thereafter, the positive electrode core material PB is conveyed into the drying furnace 1300 in the direction of the arrow I2 in FIG. At this time, the positive electrode core material PB is conveyed in the direction of the arrow J1 in FIG.

  The direction of the positive electrode core material PB whose first surface has been dried can be changed by a folding roller 1401. By the folding roller 1401, the positive electrode core material PB is conveyed in the direction of the arrow I3 in FIG. Subsequently, the direction of the positive electrode core material PB is changed by a folding roller 1402. And the positive electrode core material PB is conveyed in the direction of arrow I4 in FIG. The direction is the direction of the arrow J2 in FIG.

  And the direction of a 1st surface and a 2nd surface is replaced by the front-back inversion apparatus 1600 of the positive electrode core material PB. Therefore, the second surface faces upward before the positive electrode core material PB reaches the front / back reversing device 1600, but after the positive electrode core material PB passes through the front / back reversing device 1600, the first surface faces upward. It is in the state of facing. The positive electrode core material PB is conveyed in the direction of the arrow I5 in FIG. 6, that is, the direction of the arrow J3 in FIG.

  Then, the positive electrode core material PB is conveyed to the location of the second surface coating die 1221 in the direction of the arrow I6 in FIG. The positive electrode core material PB coated on the second surface is conveyed in the direction of arrow I2 in FIG. 6, that is, in the direction of arrow J4 in FIG. Here, the direction of the arrow J4 in FIG. 7 is the same as the direction of the arrow J1 in FIG. That is, the direction in which the positive electrode core material PB is conveyed to the drying furnace 1300 when drying the paste layer on the first surface, and the direction in which the positive electrode core material PB is conveyed to the drying furnace 1300 when drying the paste layer on the second surface. Is the same. Since the positive electrode core material PB is conveyed inside the drying furnace 1300 in the direction of the arrow J4 in FIG. 7, the second surface of the positive electrode core material PB is dried. Then, the positive electrode core material PB is wound up.

4). Battery Manufacturing Method Next, a battery manufacturing method of this embodiment will be described. The battery manufacturing method according to this embodiment is characterized in that the electrode plate manufacturing apparatus 1000 is used for manufacturing the positive electrode plate PX and the negative electrode plate NX.

4-1. Coating liquid kneading step First, a kneading step for creating a positive electrode paste for forming the positive electrode mixture layer PA will be described. As the positive electrode active material, the conductive material, the thickener, the binder, and the solvent used here, the above materials may be used. Then, in the kneader, the positive electrode active material, the conductive material, the binder, and the thickening material are mixed in the solvent and stirred with the kneading blade. Thereby, the paste for positive electrodes is created. The negative electrode paste can be similarly prepared.

4-2. Electrode Plate Creation Step The positive electrode plate PX is created using the electrode plate manufacturing apparatus 1000 shown in FIGS. The positive electrode core material PB is unwound from the unwinding reel 1101 of the unwinding portion 1100. Next, the positive electrode paste is applied to the first surface of the positive electrode core material PB with the first surface coating die 1211. Subsequently, the coated positive electrode core material PB is conveyed to the first surface drying path 1700. Therefore, the paste layer on the first surface is dried.

  Next, the positive electrode core material PB from which the paste layer on the first surface has been dried is transported to the transport route 1900 before the second surface coating. Then, the first surface and the second surface of the positive electrode core material PB are reversed by the front / back reversing device 1600. Thereafter, the coating liquid is applied to the second surface of the positive electrode core material PB by the second surface coating die 1221. Next, the positive electrode core material PB having the paste layer coated on the second surface is conveyed to the second surface drying path 1800. Then, the paste layer on the second surface of the positive electrode core material PB is dried. The positive electrode core material PB from which the paste layer on the second surface has been dried is taken up by a take-up reel 1501 of the take-up unit 1500.

  The positive electrode plate PX thus produced is cut along the line L in FIG. Thereby, the positive electrode plate P shown in FIG. 4 is obtained.

  The negative electrode plate NX can be similarly produced. It is preferable that the furnace temperatures of the first drying furnace 1310, the second drying furnace 1320, and the third drying furnace 1330 are set based on the drying profile for the negative electrode.

4-3. Next, using a winding device 2000 shown in FIG. 10, the positive electrode plate P and the negative electrode plate N are laminated and wound with separators S and T interposed therebetween. The winding device 2000 includes a positive electrode plate supply unit 2001, a negative electrode plate supply unit 2002, separator supply units 2003 and 2004, and a winding shaft 2005. Here, as shown in FIG. 3, the positive electrode plate P, the separator S, the negative electrode plate N, and the separator T are stacked and wound in order from the inside. The wound electrode body 100 is created by rotating the wound shaft 2005 in the direction of arrow F in FIG.

4-4. Battery Assembly Step Subsequently, the wound electrode body 100 is disposed in the battery container 11. Then, an electrolytic solution is injected into the battery container 11. The lid 12 is then sealed. Thereby, the battery 10 of this embodiment is assembled. After this, it is advisable to perform processing such as conditioning and aging and various inspection processes. The battery 10 of this embodiment is manufactured through the above steps.

5. Modified example 5-1. Transport Method in Drying Furnace In this embodiment, as shown in FIG. 6, a roller 1302 is used for transporting the electrode core material in the drying furnace 1300. However, the conveyance of the electrode core material inside the drying furnace 1300 may be performed not by roller conveyance using the roller 1302 but by an air floating method.

5-2. Air Nozzle In the present embodiment, the temperature, wind speed, and air volume of hot air ejected from each of the air nozzles 1301 are equal in the first drying furnace 1310. However, the temperature, wind speed, and air volume of the hot air may be changed for each air nozzle 1301. This is because the applied paste layer can be dried based on a more detailed drying profile.

5-3. Heating method In this embodiment, the paste was dried by blowing hot air from the air nozzle 1301 toward the paste layer of the electrode core material. However, other heating methods may be used as long as the paste is dried. For example, infrared heating (IR) or induction heating (IH) can be used.

5-4. Arrangement of Front and Back Reversing Device As shown in FIG. 6, in this embodiment, the front and back reversing device 1600 is arranged near the center of the second drying furnace 1320. However, the front / back reversing device 1600 may be disposed at a position other than this. As long as it is a position from the position downstream of the drying path of the first surface to the upstream of the second surface coating die 1221, it may be arranged at any position. That is, any position may be used as long as it is in the middle of the second surface coating pre-coating conveyance paths 1900 and 1901. However, in order to reduce the influence at the time of coating the second surface, it is preferably provided at a position away from the second surface coating die 1221.

5-5. Number of Connections of Drying Furnace In the drying furnace 1300 of this embodiment, a three-stage drying furnace including a first drying furnace 1310, a second drying furnace 1320, and a third drying furnace 1330 is provided. However, the number of ovens in this drying oven can be changed arbitrarily. Even in that case, there is no change in arranging the first surface drying path 1700 and the second surface drying path 1800 side by side. As a result, the first and second surfaces of the electrode core material can be dried with the same drying profile. The overall number of furnaces will remain small.

5-6. Direction of coating die In this embodiment, as shown in FIG. 6, the first surface coating die 1211 and the second surface coating die 1221 are placed laterally on the lateral sides of the backup rollers 1212 and 1222, respectively. It was decided that it was arranged. However, the coating die may be arranged so that coating is performed from the lower side of the backup roller. This is because the coating liquid can be applied to the electrode core material.

5-7. Position of first surface coating die and second surface coating die In FIGS. 6 and 7, the first surface coating die 1211 and the second surface coating die 1221 are arranged adjacent to each other. Has been placed. However, the position of the second surface coating die 1221 may be shifted from the position adjacent to the first surface coating die 1211 due to the design of the equipment. For example, the position of the second surface coating die 1221 can be higher than the position of the first surface coating die 1211.

5-8. The distance to the entrance of the drying furnace or the position of the second surface coating die 1221 can be arranged at a position slightly farther from or closer to the entrance of the drying furnace 1300 than the position of the first surface coating die 1211. Even in that case, the distance from the first surface coating die 1211 to the starting end 1701 of the first surface drying path 1700 and the distance from the second surface coating die 1221 to the starting end 1801 of the second surface drying path 1800 The difference from the distance is preferably within 50 cm. This is because if this difference in distance is too large, there will be a difference in the time required to enter the drying furnace 1300 after coating on the first surface and the second surface. This difference can cause a shift in the drying profile of the paste layer. Therefore, it is preferable that this difference is small.

5-9. Gravure roll In this embodiment, the first surface and the second surface of the electrode core material were coated using a coating die. However, gravure rolls can also be used for this coating. That is, a first surface gravure roll may be used instead of the first surface coating die 1211, and a second surface gravure roll may be used instead of the second surface coating die 1221. Even if it does in this way, it is because it does not change that a compound-material layer can be formed in an electrode core material.

5-10. Folded conveyance In this embodiment, the conveyance path 1900 before the second surface coating is provided inside the drying furnace 1300. However, the conveyance path 1900 before the second surface coating may be provided outside the drying furnace 1300. In that case, the front / back reversing device 1600 is provided outside the drying furnace 1300. Then, the conveyance indicated by arrows I4 and I5 in FIG. 6 is performed outside the drying furnace 1300. Even in this case, the paste layers on the first surface and the second surface of the electrode core material can be dried with the same drying profile.

  Alternatively, as shown in FIG. 11, a partition 3100 may be provided inside the first drying furnace 1310, the second drying furnace 1320, and the third drying furnace 1330. In that case, the conveyance path 1900 before the second surface coating is in a room partitioned from the first surface drying path 1700 and the second surface drying path 1800. The room temperature of the room occupied by the conveyance path 1900 before the second surface coating can be set to a temperature lower than the temperatures of the first drying furnace 1310, the second drying furnace 1320, and the third drying furnace 1330.

5-11. Folded part In this embodiment, the folding direction 1400 changes the conveying direction of the electrode core material coated with the first surface. The folded portion 1400 is outside the drying furnace 1300. However, the folded portion 1400 may be provided inside the drying furnace 1300. That is, the folding rollers 1401 and 1402 are provided inside the third drying furnace 1330. In this case, the end of the first surface drying path is a place where the folding roller 1401 is provided.

5-12. The roller of the coating part It is good to adjust the temperature of the roller which touches the electrode core material before the 1st surface coating die 1211 applies the coating liquid to the electrode core material. For example, the temperature of the roller touched by the electrode core material immediately before the first surface coating die 1211 is set to 40 ° C. Similarly, the temperature of the roller that touches the electrode core material may be adjusted before the second surface coating die 1221 applies the coating liquid to the electrode core material. Of course, the temperature set here is the same as the temperature set for the roller for the first surface. This is because the location where the electrode core material is actually coated can be set to the same temperature on the first surface and the second surface.

6). Summary As described above in detail, the electrode plate manufacturing apparatus 1000 according to the present embodiment includes the first surface coating die 1211 and the second surface coating die 1221. The first surface drying path 1700 for drying the first surface of the electrode core material, the second surface drying path 1800 for drying the second surface of the electrode core material, and the electrode core material for drying the first surface are A second pre-coating transport path 1900 for transporting to the location of the two-surface coating die 1221. And it has the front-back inversion apparatus 1600 in the middle of the conveyance path 1900 before the 2nd surface coating. Thereby, the electrode plate manufacturing apparatus 1000 which can manufacture the electrode plate which dried the paste layer of the 1st surface and the 2nd surface of an electrode core material with the same dry profile is implement | achieved.

  In the battery manufacturing method of this embodiment, the first surface drying path 1700 used for drying the paste layer on the first surface and the second surface drying path 1800 used for drying the paste layer on the second surface are the same furnace. Is placed inside. Therefore, it is possible to manufacture an electrode plate in which the paste layers on the first surface and the second surface of the electrode core material are dried with the same drying profile.

  Note that this embodiment is merely an example, and does not limit the present invention. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof. For example, it is not limited to a cylindrical battery. A battery using a wound electrode body can be similarly applied. For example, the present invention can also be applied to a prismatic battery having a flat wound electrode body produced by flat pressing a wound electrode body. Further, it can be applied to a battery using a laminated electrode body in which a positive electrode plate and a negative electrode plate are laminated without winding. Moreover, it is not restricted to a lithium ion secondary battery. The present invention can also be applied to nickel metal hydride batteries and other secondary batteries. Moreover, if it is a battery, it can apply not only to a secondary battery but to a primary battery.

DESCRIPTION OF SYMBOLS 10 ... Battery 11 ... Battery container 12 ... Cover 100 ... Winding electrode body 110 ... Positive electrode current collecting plate 120 ... Negative electrode current collecting plate 1000,3000 ... Electrode plate manufacturing apparatus 1100 ... Unwinding part 1101 ... Unwinding reel 1200 ... Coating Part 1211 ... First surface coating die 1212 ... Backup roller 1221 ... Second surface coating die 1222 ... Backup roller 1300 ... Drying furnace 1301 ... Air nozzle 1302 ... Roller 1310 ... First drying furnace 1320 ... Second drying furnace 1330 ... 3rd drying furnace 1400 ... Folding parts 1401, 1402 ... Folding roller 1500 ... Winding part 1501 ... Winding reel 1600 ... Front / back reversing device 1700 ... First surface drying path 1701 ... Starting end 1702 ... Ending 1800 ... Second surface drying Path 1801 ... Start end 1802 ... Termination 1900 ... Conveying path 2000 before second surface coating ... Spinning device 2001 ... Positive electrode plate supply unit 2002 ... Negative electrode plate supply unit 2003, 2004 ... Separator supply unit 2005 ... Winding shaft P, PX ... Positive electrode plate PA ... Positive electrode mixture layer PB ... Positive electrode core material P1 ... Positive electrode coating unit P2 ... Negative electrode non-coated portion N, NX Negative electrode plate NA Negative electrode composite layer NB Negative electrode core material N1 Negative electrode coated portion N2 Negative electrode non-coated portion S, T ... Separator

Claims (10)

A first surface coating device for applying a paste layer to the first surface of the electrode core material and a second surface coating device for applying a paste layer to the second surface of the electrode core material. The coating department,
An electrode plate manufacturing apparatus having a drying furnace for transporting an electrode core material formed with a paste layer therein and drying the paste layer;
Having a front and back reversing portion for reversing the first surface and the second surface of the conveyed electrode core material;
Inside the drying oven,
A first surface drying path for drying the paste layer on the first surface of the electrode core;
A second surface drying path for drying the paste layer on the second surface of the electrode core material is arranged in parallel;
The front and back inversion part is
An electrode plate manufacturing apparatus, wherein the electrode plate manufacturing apparatus is disposed at a position downstream of the first surface drying path and upstream of the second surface coating apparatus in an electrode core material transport path. The electrode plate manufacturing apparatus according to claim 1,
Having a second surface pre-coating transport path for transporting the electrode core material from the end of the first surface drying path to the second surface coating apparatus;
The transport path before the second surface coating is
Provided inside the drying furnace,
The front and back inversion part is
The electrode plate manufacturing apparatus, which is provided in the middle of the transport path before the second surface coating. The electrode plate manufacturing apparatus according to claim 1,
Having a second surface pre-coating transport path for transporting the electrode core material from the end of the first surface drying path to the second surface coating apparatus;
The transport path before the second surface coating is
Provided outside the drying oven,
The front and back inversion part is
The electrode plate manufacturing apparatus, which is provided in the middle of the transport path before the second surface coating. An electrode plate manufacturing apparatus according to any one of claims 1 to 3,
A distance from the coating device for the first surface to the start of the first surface drying path;
A difference between the distance from the second surface coating apparatus to the start end of the second surface drying path is within 50 cm. An electrode plate manufacturing apparatus according to any one of claims 1 to 4,
At least one of the first surface coating device and the second surface coating device is:
An electrode plate manufacturing apparatus that is a coating die. An electrode plate manufacturing apparatus according to any one of claims 1 to 4,
At least one of the first surface coating device and the second surface coating device is:
An electrode plate manufacturing apparatus, which is a gravure roll. An electrode plate forming step of applying a coating liquid to the electrode core material to form a paste layer and transporting the inside of the drying furnace to dry the paste layer to form a positive electrode plate or a negative electrode plate;
An electrode body creating step of laminating the positive electrode plate and the negative electrode plate with a separator interposed therebetween to form a laminated electrode body;
A battery assembling step of disposing the laminated electrode body inside a battery container and injecting an electrolyte into the battery container and sealing the battery,
In the electrode plate making process,
Inside the drying oven,
A first surface drying path for drying the paste layer on the first surface of the electrode core;
Using an electrode plate manufacturing apparatus in which a second surface drying path for drying the paste layer on the second surface of the electrode core material is arranged in parallel,
Apply the coating liquid to the first surface of the electrode core material to form the first paste layer,
Drying the first paste layer in the first surface drying path;
After reversing the first and second surfaces of the electrode core material,
Apply a coating solution to the second surface of the electrode core material to form a second paste layer,
A method for manufacturing a battery, wherein the second paste layer is dried by the second surface drying path. A method of manufacturing a battery according to claim 7,
In the electrode plate making process,
A direction in which the electrode core material coated with the first surface is conveyed into the drying furnace;
A method for producing a battery, characterized in that the direction in which the electrode core material coated with the second surface is conveyed into the drying furnace is the same. A method of manufacturing a battery according to claim 7 or claim 8,
In the electrode plate making process,
At least one of the first surface and the second surface of the electrode core material,
The manufacturing method of the battery characterized by coating using a coating die. A method of manufacturing a battery according to claim 7 or claim 8,
In the electrode plate making process,
At least one of the first surface and the second surface of the electrode core material,
The manufacturing method of the battery characterized by coating using a gravure roll.

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