KR20140115954A - Manufacturing method of electrode and manufacturing apparatus of electrode - Google Patents

Abstract

Provided is a method of manufacturing an electrode which is capable of applying insulation slurry onto a current collector without bending or curving the current collector when a double-surface apply process is performed. The method of manufacturing the electrode includes an insulator application process and an electrode application process. According to the insulator application process, the insulation slurry (102) is applied onto an end of the other surface (101b) facing one surface of the current collector (101) while pressing the current collector from the one surface side by using an elastic body (25b) in a state where the insulation slurry (102) applied onto the one surface (101a) of the current collector (101) and an electrode slurry (103) applied onto a portion of the one surface (101a) where the insulation slurry is not applied are dried. In the electrode apply process, the electrode slurry is applied onto a portion of the other surface where the insulation slurry is not applied.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode manufacturing method,

The present invention relates to an electrode manufacturing method and an electrode manufacturing apparatus.

Conventionally, an electric device has been constructed by housing a power generating element by a casing. The power generating element is formed by laminating a plurality of positive electrodes and negative electrodes via a separator. The positive electrode and the negative electrode are formed by coating the current collector with an electrode slurry and drying the same.

In some cases, the positions of internal constituent members are displaced relative to each other due to external stress or vibration. For example, in the case of a power generating element, when the position of the positive electrode and the negative electrode which are insulated via the separator are shifted, there is a possibility that the end portion of the positive electrode and the end portion of the negative electrode come into contact with each other and short-

Therefore, in the electric power generating element, there is a constitution in which, even if the positions of the positive electrode and the negative electrode which are insulated via the separator are shifted from each other, they are not short-circuited. For example, if an insulating tape having an insulating property is attached to the end portion of the positive electrode, short-circuiting can be prevented even if the end portion of the positive electrode and the end portion of the negative electrode come into contact with each other.

However, in the configuration in which the insulating tape is attached to the end portion of the positive electrode or the negative electrode, a special device for attaching the insulating tape is required in addition to the insulating tape, so that the manufacturing cost and tact of the electrode are increased.

Therefore, an insulator is formed on the electrode. Specifically, there is a constitution in which an electrode slurry and an electrode slurry are applied to an electrode and dried, respectively. The apparatus for applying an insulator slurry has the same basic specifications as the apparatus for applying an electrode slurry, and a special apparatus is not required (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2007-258050

However, in the structure of Patent Document 1, there arises a problem in the case of the double-side coating application in which the electrode slurry is applied to both surfaces of the current collector and dried. That is, in the case of the one-side coating application, since the insulator slurry and the electrode slurry can be appropriately applied to the surface of the current collector in a state in which the back-up roll is in close contact with the back side of the current collector, no particular problem arises.

On the other hand, in the case of the double-side coating application, the insulator slurry and the electrode slurry are coated on the back surface of the current collector in a state in which the backup roll is in close contact with the surface of the current collector. Here, in the double-side coating application, the dried insulation layer and the electrode layer are formed on the surface of the collector on which the backup roll is brought into close contact with the slurry, but the thickness thereof may be different.

For example, when the thickness of the electrode layer and the thickness of the insulator layer are different, the current collector pressed by the back-up roll is bent or bent at the boundary between the portion where the electrode layer is formed and the portion where the insulator layer is formed. When the current collector is bent or bent, an error occurs in the dimension, or air is caught in a gap generated in the bent portion and pinholes are generated.

Therefore, it takes time to adjust the application conditions of the insulator slurry and the electrode slurry to the current collector at the time of double-side application, and it may be difficult to keep the state of the coating application constant. As described above, there is a possibility that the insulator slurry and the electrode slurry can not be applied without refracting or bending the current collector when the double-side coating is applied.

An object of the present invention is to provide an electrode manufacturing method capable of applying an insulator slurry without refracting or bending a current collector when a double-side coating is applied, and an electrode manufacturing apparatus embodying the manufacturing method The purpose.

To attain the above object, the electrode manufacturing method of the present invention has a step of applying an insulator and a step of applying an electrode. In the insulator coating step, the insulator slurry applied to the end of one surface of the current collector and the electrode slurry applied to the portion where the insulator slurry on one surface is not coated are dried, and the current collector is pressed The insulator slurry is applied to the end of the other surface opposite to one surface of the current collector. In the electrode coating step, the electrode slurry is applied to a portion where the insulator slurry on the other surface is not coated.

In order to attain the above object, an electrode manufacturing apparatus of the present invention has an insulator applying section and an electrode applying section. The insulator coating portion is formed by inserting the insulator slurry coated on one end of the current collector and the electrode slurry coated on the portion where the insulator slurry on one side is not coated, , And the insulator slurry is applied to the end of the other surface opposite to one surface of the current collector. The electrode application portion applies the electrode slurry to a portion where the insulator slurry on the other surface is not coated.

According to the electrode manufacturing method of the present invention and the electrode manufacturing apparatus embodying the manufacturing method of the present invention, in a state in which the insulator slurry and the electrode slurry applied to one surface of the current collector are dried, the current collector is pressed , And the insulator slurry is applied to the end of the other surface opposite to one surface of the current collector. Therefore, it is possible to apply the insulator slurry without refracting or bending the current collector during the double-side coating application.

1 is a perspective view showing an electrode manufacturing apparatus according to a first embodiment;
2 is a perspective view showing a main part of an electrode manufacturing apparatus according to the first embodiment;
3 is a side view showing an electrode manufacturing apparatus according to the first embodiment;
4 is a side view showing a main part of an electrode manufacturing apparatus according to the first embodiment;
5 is a perspective view showing a state in which electrodes manufactured by using the electrode manufacturing apparatus according to the first embodiment are laminated via a separator.
6 is a schematic diagram showing a state of a single-sided coating application in which an insulator slurry and an electrode slurry are applied to one surface of a current collector and dried using the electrode manufacturing apparatus according to the first embodiment;
Fig. 7 is a schematic cross-sectional view of an electrode manufacturing apparatus according to the first embodiment, in which an insulator slurry and an electrode slurry are coated on the other surface of the current collector after applying the insulator slurry and the electrode slurry on one surface thereof, Fig. 3 is a schematic view showing a state of a two-side coating application. Fig.
8 is a perspective view showing an insulator applying section of the electrode manufacturing apparatus according to the second embodiment.
9 is a view showing a main part of a single-sided coating application of an insulator slurry to a current collector using an electrode manufacturing apparatus according to the second embodiment.
10 is a view showing a main part of a double-side application of an insulator slurry to a current collector using an electrode manufacturing apparatus according to a second embodiment;
Fig. 11 is a schematic cross-sectional view showing a state in which an insulator slurry and an electrode slurry are coated on one surface of a current collector and dried on the other surface of the current collector, and then an insulation slurry is coated on the other surface of the current collector Fig.

Hereinafter, the first and second embodiments will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant explanations are omitted. The sizes and ratios of the respective members in the drawings are exaggerated for convenience of explanation and may differ from actual sizes and ratios.

(First Embodiment)

The electrode manufacturing apparatus 1 embodying the electrode manufacturing method and the electrode manufacturing method according to the first embodiment will be described with reference to Fig. 11, which is a comparative example, in addition to Figs.

The transporting step, the insulator applying step, the electrode applying step and the drying step in the electrode manufacturing method are the same as those of the transporting part 10, the insulator applying part 20, the electrode applying part 30, And corresponds to the drying section 40. Therefore, the first embodiment will be described based on the electrode manufacturing apparatus 1 embodying the electrode manufacturing method.

First, the configuration of the electrode manufacturing apparatus 1 will be described with reference to Figs. 1 to 5. Fig.

Fig. 1 is a perspective view showing an electrode manufacturing apparatus 1. Fig. Fig. 2 is a perspective view showing a main part of the electrode manufacturing apparatus 1. Fig. 2 (a) shows a main part of the electrode manufacturing apparatus 1 from above, and FIG. 2 (b) shows a main part of the electrode manufacturing apparatus 1 from below. 3 is a side view showing the electrode manufacturing apparatus 1. Fig. Fig. 4 is a side view showing a main part of the electrode manufacturing apparatus 1. Fig. 5 is a perspective view showing a state in which electrodes fabricated using the electrode manufacturing apparatus 1 are laminated via a separator 200. Fig. 5 (a) shows the state before lamination, and Fig. 5 (b) shows the state after lamination.

The carry section 10 carries the current collector 101 in which the insulator slurry 102 and the electrode slurry 103 are applied and dried, respectively.

The conveying unit 10 is a conveying unit for conveying the current collector 101 along the conveying path such as the current collector supply roll 11, the drive roll 12, the driven roll 13, the take- 15 and an electrode winding roll 16.

The collector feed roll 11 is formed in a cylindrical shape rotatably retained and holds the collector 101 before the insulator slurry 102 and the electrode slurry 103 are applied in a roll form have. For the current collector 101, for example, a metal foil made of aluminum, copper, nickel, iron or stainless steel is used. Concretely, for the current collector 101 for the positive electrode, for example, a metal foil of aluminum having a thickness of 20 mu m is used. On the other hand, for the collector 101 for the negative electrode, for example, a metal foil made of copper and having a thickness of 10 mu m is used.

The current collector supply roll 11 supplies the current collector 101 while rotating in conjunction with the drive roll 12 to be described later. The driving roll 12 and the driven roll 13 are each formed into a columnar shape that is rotatably retained and the current collector 101 supplied from the current collector supplying roll 11 is directed toward the insulator applying portion 20 Guide. The outer periphery of the drive roll 12 is made of metal, and the outer periphery of the driven roll 13 is made of rubber. The driving roll 12 and the driven roll 13 carry the current collector 101 while holding the current collector 101 therebetween. When the driving roll 12 rotates, the driven roll 13 rotates with its rotation.

The carry-in roll 14 has a cylindrical shape rotatably retained and guides the current collector 101 coated with the insulator slurry 102 and the electrode slurry 103 toward the drying unit 40. The carry-in roll 14 is in contact with the back side of the current collector 101 to which the insulator slurry 102 and the electrode slurry 103 are not applied. The take-out roll 15 has a cylindrical shape rotatably held and guides the dried electrode 100 taken out from the drying unit 40 toward the electrode take-up roll 16. The electrode winding roll 16 is formed in a cylindrical shape that is rotatably held and is wound by holding the electrode 100 guided by the take-out roll 15. The electrode winding roll 16 is rotationally driven at a constant speed by a motor (not shown).

The insulator application portion 20 applies the insulator slurry 102 to the end portion of the current collector 101.

The insulator application portion 20 includes an insulator slurry 102 coated on an end of one surface 101a of the current collector 101 and an electrode slurry 102 coated on a portion of the surface 101a where the insulator slurry 102 is not coated The other surface 101b opposite to the one surface 101a of the current collector 101 while pressing the current collector 101 from the one surface 101a side by the elastic body 25b while the slurry 103 is dried, The insulator slurry 102 is applied to the end portion of the insulator slurry.

The insulator application portion 20 includes a coating application die 21 for applying an insulator, a liquid storage tank 22, a liquid delivery pump 23, a liquid delivery pipe 24 and a backup roll 25 for applying an insulator .

The application coating die 21 for applying an insulator applies the insulator slurry 102 to the current collector 101 to a predetermined thickness. The application dies 21 for applying an insulator are formed as a pair and are disposed at both ends of the current collector 101 along the conveying direction of the current collector 101. Specifically, the pair of coating application dies 21 for applying an insulating material are formed between the drive roll 12 of the carry section 10 and the electrode application coating die 31 of the electrode application section 30 described later Respectively. The application coating die 21 for applying an insulating material is in contact with the current collector 101 pressed by a back-up roll 25 for insulator coating to be described later from the surface side opposite to the current collector 101.

The insulator slurry 102 to be applied to the current collector 101 by the application coating die 21 for insulator coating is made of a resin having an insulating property and a compound thereof and the thickness of the current collector 101 Is set to be 45 mu m after drying. As the resin used for the insulator slurry 102, for example, a two-liquid curable resin such as polyvinylidene fluoride or a derivative thereof, urethane resin, epoxy resin and alkyd resin or an electron beam curable resin is used. The insulator slurry 102 contains ceramics composed of alumina, titanium oxide, talc or the like in order to improve the insulating property. The particle diameter of the ceramics is set to 0.1 mu m to 15 mu m in consideration of the thickness of the insulator slurry 102 after drying.

The dispersibility of the compound used for the insulator slurry 102 is important. Since ceramics such as alumina have chemical properties and are hydrophilic, it is difficult to disperse them in the resin as they are. In general, a surfactant may be used in a compound, but it may not adversely affect the characteristics of the battery, and therefore is not suitable for battery applications. Therefore, a carboxyl group-modified polyvinylidene fluoride resin or a urethane resin having a dispersing function is used for the resin. When such a resin is used, an insulator slurry 102 having excellent dispersibility can be obtained. As a compound, a bead mill excellent in dispersibility can be used. The bead mill is made of, for example, alumina or zirconia, and preferably has a particle diameter of 30 to 2 mm. By using the above method, alumina can be easily dispersed, and it is possible to obtain a uniform insulator slurry 102.

The liquid storage tank 22 is made of a cylindrical metal container having a closed bottom, and stores a predetermined amount of the insulator slurry 102. The liquid sending pump 23 is connected to the liquid storage tank 22 and feeds the insulator slurry 102 stored in the liquid storage tank 22 to the applied coating die 21 for insulator coating via the liquid feed pipe 24 do. One end of the liquid pipe 24 is connected to the liquid feed pump 23 and the other end thereof is connected to a pair of the application dies 21 for applying an insulator.

The back-up roll 25 for applying an insulator is pressed against the current collector 101 which is contacted by the application die 21 for applying an insulator from the opposite side. The backup roll 25 for applying an insulator is constituted by an axial core 25a and an elastic body 25b.

The axis 25a is made of, for example, metal and is formed into a cylindrical shape. The outer peripheral surface of the shaft center 25a is sandblasted. The elastic body 25b covers the axis 25a. Specifically, the elastic body 25b is formed into a cylindrical shape by covering the shaft center 25a coated with the adhesive with, for example, rubber having a predetermined strength, and then uniformly polishing the outer side thereof.

As the material of the elastic body 25b of the backing roll 25 for applying an insulating material, diene rubber, natural rubber (NR), acrylonitrile butadiene rubber (NBR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), chloroprene rubber (CR), silicone rubber or urethane rubber can be used. As the material of the elastic body 25b, a thermoplastic resin such as a polyethylene resin, a polypropylene resin, a polystyrene resin, an acrylonitrile-butadiene styrene resin, or a soft plastic material produced therefrom may be used.

A suitable material for the elastic body 25b is, for example, a diene rubber. Diene rubbers use liquid paraffin as a plasticizer for adjusting the hardness. The liquid paraffin does not affect the characteristics of the battery even when it is transferred and adhered to the electrode material during the application process. Further, since the liquid paraffin has a low coefficient of friction, the electrode material can be lubricated and moved. That is, the liquid paraffin can be stably transported without generating wrinkles or the like on the electrode material.

As described above, the elastic body 25b can be formed using a material which is a general-purpose product and which is excellent in workability and inexpensive. The liquid paraffin used as a plasticizer is also widely used and can be obtained at low cost.

The layer thickness of the elastic body 25b is proportional to the thickness of the dried electrode slurry 103. For example, in the case where the thickness of the dried electrode slurry 103 is 120 占 퐉 including the thickness of the current collector 101, considering that the thickness of the elastic body 25b absorbs the thickness of 120 占 퐉, For example, 200 mu m. Even if the surface of the elastic body 25b is worn, it can be reused by re-polishing the surface of the elastic body 25b, and the life of the elastic body 25b can be prolonged. The layer thickness of the elastic body 25b is preferably 10 mm or more in consideration of the reheat.

Here, verification results of an appropriate specification regarding the elastic body 25b will be described with reference to Table 1.

The verification of the elastic body 25b was performed with respect to the dimensional accuracy and surface state of the coating application. The dimensional accuracy of the coating application is required to be within ± 1 mm with respect to the reference value in consideration of prevention of short circuit between the electrodes caused by positional shift of each electrode when stacking a plurality of electrodes. It is required that the surface state does not cause the formation of the pinhole-shaped hole in consideration of the prevention of short-circuiting between the electrodes generated by the foreign matter being drawn into the hole of the pinhole shape.

In Experimental Examples 1 to 4 relating to the elastic body 25b, nitrile butadiene rubber (NBR) was used as the material of the elastic body 25b. The hardness of the rubber was adjusted by varying the addition amount of the plasticizing liquid paraffin. The hardness of the rubber was measured on the basis of a measurement method relating to " durometer A " specified in ISO (International Organization for Standardization) or a new JIS standard. In Experimental Examples 1, 2, 3 and 4 relating to the elastic body 25b, the rubber hardnesses correspond to A-10, A-30, A-50 and A-70.

In Comparative Examples 1 and 2 relating to the elastic body 25b, the same nitrile butadiene rubber (NBR) as in Experimental Examples 1 to 4 was used, and the rubber hardness was equivalent to A-5 and A-75. That is, Comparative Example 1 is relatively soft compared to Experimental Examples 1 to 4, and Comparative Example 2 is relatively harder than Experimental Examples 1 to 4. Using the rubbers according to Experimental Examples 1, 2, 3 and 4 and Comparative Examples 1 and 2, the conditions of the coating application were compared and verified. Table 1 shows the results of the comparative verification.

As a result of the verification with respect to the elastic body 25b, it is preferable that the dimensional accuracy of the elastic body 25b is within ± 1 mm and that no holes are formed on the surface, 4, respectively. Particularly, in Experimental Examples 2 and 3 in which the rubber hardness corresponds to A-30 to A-50, it was found that the dimensional accuracy of the elastic body 25b was better, i.e., +/- 0.5 mm.

On the other hand, if the rubber hardness is too weak as A-5 as in Comparative Example 1, since the repulsive force of the rubber is weak and the force for pressing toward the current collector 101 is insufficient, a force pressing the portion of the end surface flat Lack. Likewise, when the rubber hardness is too hard as A-75 as in Comparative Example 2, the repulsive force of the rubber is strong, and the force pressing the portion of the end face flat becomes excessive.

The electrode applying section 30 applies the electrode slurry 103 to a portion of the current collector 101 where the insulator slurry 102 is not coated.

The electrode application portion 30 includes a coating application die 31 for coating an electrode, a liquid storage tank 32, a liquid delivery pump 33, a liquid delivery pipe 34 and a backup roll 35 for applying an electrode .

The electrode application coating die 31 applies the electrode slurry 103 to the current collector 101 to a predetermined thickness. The electrode application coating die 31 is disposed so as to be in contact with a portion of the current collector 101 excluding the both ends thereof along the conveying direction of the current collector 101, for example. Specifically, the electrode application coating die 31 is located between the application coating die 21 for applying an insulating material and the take-in roll 14. The electrode application coating die 31 is in contact with the current collector 101 pressed from the back side by the backup roll 35 for applying the electrode from the surface side of the current collector 101.

The electrode slurry 103 to be applied to the current collector 101 by the application coating die 31 for electrode coating is for positive electrode and negative electrode. When the electrode slurry 103 is for a positive electrode, for example, a lithium-transition metal composite oxide is used as the active material. On the other hand, when the electrode slurry 103 is for the negative electrode, for example, graphite, hard carbon, or a lithium-transition metal composite oxide is used as the active material. As the conductive auxiliary agent, for example, acetylene black, carbon black or graphite is used. As the binder, for example, polyvinylidene fluoride (PVDF) is used. As the solvent, for example, normal methyl pyrrolidone (NMP) or water is used. The solvent is removed by evaporation during drying.

The liquid storage tank 32 is made of a cylindrical metal container having a closed bottom, and stores a predetermined amount of the electrode slurry 103. The liquid feed pump 33 is connected to the liquid storage tank 32 and feeds the electrode slurry 103 stored in the liquid storage tank 32 to the electrode application coating die 31 through the liquid feed pipe 34 do. One end of the liquid pipe 34 is connected to the liquid feed pump 23 and the other end of the pipe is connected to the electrode application coating die 31.

The backup roll 35 for applying the electrode is pressed against the current collector 101 to which the electrode application coating die 31 is contacted from the surface opposite to the current collector 101. [ The backup roll 35 for applying an electrode is made of, for example, metal or rubber, and is formed into a cylindrical shape.

The drying section 40 dries the insulator slurry 102 and the electrode slurry 103 applied to the current collector 101.

The drying unit 40 includes a housing 41, a heater 42, and a support roll 43, for example.

The drying unit 40 includes a heater 42 and a plurality of support rolls 43 in a housing 41 formed in a rectangular parallelepiped shape. The housing 41 is made of a heat insulating material, and temporarily houses the current collector 101 during transportation. The housing 41 is located downstream of the carrying roll 10 in the transport direction of the current collector 101 and is closer to the current collector 101 than the take-out roll 15 provided in the carry section 10, In the conveying direction.

The heater 42 is disposed inside the housing 41 so as to face the insulator slurry 102 and the electrode slurry 103 applied to the current collector 101. The heater 42 evaporates the solvent contained in the insulator slurry 102 and the electrode slurry 103 and dries them. The support rolls 43 are provided in the drying unit 40 at a predetermined interval. The heater slurry 102 and the electrode slurry 103 are dried by the heater 42 while the current collector 101 is being conveyed by the support roll 43. [

The electrode 100 manufactured using the electrode manufacturing apparatus 1 described above is stacked with the separator 200 interposed therebetween as shown in Fig.

The electrode 100 manufactured using the electrode manufacturing apparatus 1 may be either the positive electrode 100a or the negative electrode 100b but is assumed to be the positive electrode 100a. As shown in Fig. 5A, the positive electrode 100a has an insulator layer 102 'formed by coating an insulator slurry 102 on both ends of the positive electrode 100a and drying it. The positive electrode 100a has an electrode layer 103 'formed by applying an electrode slurry 103 to a portion other than both ends and drying the same. On the other hand, the negative electrode 100b includes an electrode layer 103 'formed by applying electrode slurry 103 including both end portions and drying the same. The positive electrode 100a and the negative electrode 100b are laminated via the separator 200, as shown in Fig. 5 (b). Therefore, even if the ends of the positive electrode 100a and the negative electrode 100b are misaligned with each other, short-circuiting can be prevented because the insulator layer 102 'is formed at the end of the positive electrode 100a.

Next, a method of manufacturing the electrode 100 using the electrode manufacturing apparatus 1 will be described with reference to Figs. 6 and 7 and a comparative example with reference to Fig.

6 is a schematic view showing a state of a single-sided coating application in which an insulator slurry 102 and an electrode slurry 103 are coated on one surface 101a of the current collector 101 and dried using the electrode manufacturing apparatus 1 to be. 7 shows a state in which the current collector 101 is applied to the current collector 101 after the insulator slurry 102 and the electrode slurry 103 are coated on one surface 101a and dried, In which the insulator slurry 102 and the electrode slurry 103 are coated on the other surface 101b of the substrate 101 and dried. 11 is a schematic view showing the structure of a current collector 101 of a current collector 101 obtained by coating an insulator slurry 102 and an electrode slurry 103 on one surface 101a and drying the same, In which the insulator slurry 102 is applied to the other surface 101b of the substrate 101. In this case,

A method of applying the slurry to the current collector 101 using the electrode manufacturing apparatus 1 is described with reference to Fig.

6, the insulator slurry 102 and the electrode slurry 103 are coated on one surface 101a of the current collector 101 and dried using the electrode manufacturing apparatus 1. Then, as shown in Fig.

6 (a), while the current collector 101 is sandwiched between the drive roll 12 and the driven roll 13 in the carry section 10, And the collector 101 is transported. 6 (b), while the current collector 101 is pressed from the side of the other surface 101b by the backup roll 25 for applying an insulator in the insulator application portion 20, Insulator slurry 102 is applied to both ends of one face 101a of the current collector 101 by using a coating die 21 for applying an insulator.

6 (c), while the current collector 101 is pressed from the side of the other surface 101b by the electrode applying backup roll 35 in the electrode application portion 30, The electrode slurry 103 is coated on one surface 101a of the current collector 101 by using a coating die 31 for electrode coating. 6 (d), the insulator slurry 102 and the electrode slurry 103 coated on one surface 101a of the current collector 101 are heated by the heater 40 in the drying section 40, (42) to form an insulator layer (102 ') and an electrode layer (103').

A method of applying the slurry to both surfaces of the current collector 101 using the electrode manufacturing apparatus 1 will be described with reference to FIG.

7, in the current collector 101 after the insulator layer 102 'and the electrode layer 103' are formed on the one surface 101a, the current collector The insulator slurry 102 and the electrode slurry 103 are coated on the other surface 101b of the substrate 101 and dried.

Concretely, at first, as shown in Fig. 7A, while the current collector 101 is sandwiched by the drive roll 12 and the driven roll 13 in the carry section 10, And the collector 101 is transported. Next, as shown in Fig. 7 (b), while the current collector 101 is pressed from the side of the one surface 101a by the backup roll 25 for applying an insulator in the insulator applying portion 20, Insulator slurry 102 is applied to both ends of the other surface 101b of the current collector 101 by using a coating die 21 for applying an insulator.

The already dried insulator layer 102 'and the electrode layer 103' are formed on one surface 101a of the current collector 101 that closely contacts the back-up roll 25 for applying an insulator, but the thickness thereof is different . The current collector 101 pressed by the back-up roll 25 for insulator coating has a portion where the electrode layer 103 'is formed and a portion of the insulator layer 102' which is thinner than the layer thickness of the electrode layer 103 ' There is no bending or bending at the boundary of the portion where the layer 102 'is formed. Since the outer periphery of the backup roll 25 for applying an insulator is covered with the elastically deformable elastic body 25b, the current collector 101 is not bent or bent.

That is, even if a step is formed at the boundary between the portion where the electrode layer 103 'is formed and the portion where the insulator layer 102' is formed, the step can be absorbed by the elastic body 25b. Since the current collector 101 is not bent or bent, the dimensional accuracy of the current collector 101 is maintained. In addition, it is possible to prevent the occurrence of pinholes in which air is entrained in the gap of the bent or bent portion.

Next, as shown in Fig. 7C, while the current collector 101 is pressed from the side of the one surface 101a by the electrode applying backup roll 35 in the electrode application portion 30, The electrode slurry 103 is applied to the other surface 101b of the current collector 101 by using the application coating die 31 for electrode coating. Finally, as shown in Fig. 7 (d), in the drying section 40, the insulator slurry 102 and the electrode slurry 103 coated on the other surface 101b of the current collector 101 And dried by a heater 42 to form an insulator layer 102 'and an electrode layer 103'.

Here, a part of the method of applying the slurry to both surfaces of the current collector 101 by using the electrode production apparatus according to the comparative example will be described with reference to Fig.

11 (a), in the transport section 1010 of the comparative electrode production apparatus, the insulator slurry 102 and the electrode slurry 103 are coated on one surface 101a and dried, (101) is sandwiched and conveyed by the drive roll (1012) and the driven roll (1013). 11 (b), while the current collector 101 is pressed from the side of the one surface 101a by the backup roll 1025 for applying an insulator in the insulator applying portion 1020, The insulator slurry 102 is applied to the other surface 101b of the current collector 101 by using the applied coating die 1021 for applying an insulator.

Here, the layer thickness of the insulator layer 102 'and the electrode layer 103' formed on the other surface 101b of the current collector 101 to which the backup roll 1025 for applying an insulator is closely contacted is different. Therefore, the current collector 101 pressed against the backup roll 1025 for applying an insulator is refracted, for example, at the boundary between the portion where the electrode layer 103 'is formed and the portion where the insulator layer 102' is formed. As a result, the dimensional accuracy of the current collector 101 is lowered, and if a plurality of electrodes are stacked, there is a possibility that the electrodes are short-circuited to each other. Further, when the current collector 101 is bent, air is drawn into a gap generated in the bent portion, and pinholes are generated. If foreign matter is drawn into the hole of the pinhole shape, the electrode may be short-circuited.

According to the electrode manufacturing method of the first embodiment and the electrode manufacturing apparatus 1 embodying the electrode manufacturing method described above, the following operation effects are exhibited.

The electrode manufacturing method has an insulator applying step and an electrode applying step. The insulator coating step is carried out in such a manner that the insulator slurry 102 coated on the end of one surface 101a of the current collector 101 and the electrode slurry 103 coated on the portion where the insulator slurry 102 on one surface 101a is not coated The current collector 101 is pressed against the end face of the other face 101b opposite to the one face 101a of the current collector 101 while pressing the current collector 101 from the side of the one face 101a by the elastic body 25b Insulator slurry 102 is applied. The electrode coating step applies the electrode slurry 103 to a portion of the other surface 101b where the insulator slurry 102 is not coated.

The electrode manufacturing apparatus 1 has an insulator applying section 20 and an electrode applying section 30. The insulator application portion 20 includes an insulator slurry 102 coated on an end of one surface 101a of the current collector 101 and an electrode slurry 102 coated on a portion of the surface 101a where the insulator slurry 102 is not coated The other surface 101b opposite to the one surface 101a of the current collector 101 while pressing the current collector 101 from the one surface 101a side by the elastic body 25b while the slurry 103 is dried, The insulator slurry 102 is applied to the end portion of the insulator slurry. The electrode applying section 30 applies the electrode slurry 103 to a portion of the other surface 101b where the insulator slurry 102 is not coated.

According to the electrode manufacturing apparatus 1 in which the electrode manufacturing method and the electrode manufacturing method are embodied, the insulator slurry 102 and the electrode slurry 103 coated on one surface 101a of the current collector 101 are dried The insulator slurry 102 is applied to the end of the other surface 101b opposite to the one surface 101a of the current collector 101 while the current collector 101 is pressed by the elastic body 25b from the one surface 101a side Lt; / RTI > Therefore, it is possible to apply the insulator slurry 102 without refracting or bending the current collector 101 at the time of double-side application. Since the current collector 101 is not bent or bent, the dimensional accuracy of the current collector 101 is maintained, and shorting of the electrodes 100 can be prevented even when a plurality of electrodes 100 are laminated. In addition, it is possible to prevent the occurrence of pinholes in which air is entrained in the gap of the bent or bent portion.

The electrode manufacturing method may be such that the insulator slurry 102 is applied to the current collector 101 by an insulator coating step and then the electrode slurry 103 is applied to the current collector 101 by an electrode coating step.

With this configuration, the current collector 101 can be continuously wound without rubbing the portion of the insulator slurry 102 of the current collector 101.

The electrode manufacturing method may further include a drying step. In the drying step, the insulator slurry 102 and the electrode slurry 103 applied to the current collector 101 are dried.

With such a configuration, the shape of the insulator slurry 102 and the electrode slurry 103 applied to the current collector 101 can be maintained and dried continuously in the drying step after each coating step. In addition, it is not necessary to transport the current collector 101 coated with the insulator slurry 102 and the electrode slurry 103 to another apparatus, and productivity can be improved.

The electrode manufacturing method may be such that the insulator slurry 102 is applied to both opposite end portions of the current collector 101 in the insulator applying step.

According to such a configuration, it is possible to prevent a short circuit between the electrodes even if the positions of the opposite ends of the current collector 101 are shifted in one direction or the other.

The electrode manufacturing method may further include a carrying step. The conveying step conveys the current collector 101. Here, in the insulator coating step, the insulator slurry 102 is applied to both ends or one end portion of the collector 101 opposite to each other along the conveying direction.

According to this structure, since the electrode slurry 103 is applied while applying the insulator slurry 102 to the current collector 101, the work can be continuously performed, and the productivity can be improved. The insulator slurry 102 and the electrode slurry 103 can be accurately and precisely formed on the current collector 101 by determining the relative positions of the application coating die 21 for applying an insulator and the application die 31 for electrode coating, It is possible to apply roads. That is, the relative positions of the insulator slurry 102 and the electrode slurry 103 can be kept constant, and the insulator slurry 102 and the electrode slurry 103 can be stacked, It is possible to prevent a gap from being generated between the electrodes.

The thickness of the elastic body 25b may be made thicker than the thickness of the electrode slurry 103 after drying.

According to this structure, the thickness of the insulator layer 102 'is very thin when the two-side coating is applied, and the difference between the thickness of the insulator layer 102' and the thickness of the electrode layer 103 ' Even if it is approximate, the difference in the thickness can be sufficiently absorbed by the elastic body 25b.

The elastic body 25b may be configured so as to be capable of being rebonded.

According to this configuration, even if the surface of the elastic body 25b is worn, the surface of the elastic body 25b can be reused if it is re-smoothed, and the life of the elastic body 25b can be prolonged. Therefore, the cost required for replacement of the elastic body 25b can be suppressed.

(Second Embodiment)

An electrode manufacturing apparatus embodying the electrode manufacturing method and the electrode manufacturing method according to the second embodiment will be described with reference to Figs. 8 to 10. Fig.

8 is a perspective view showing the insulator applying portion 50 of the electrode manufacturing apparatus. 9 is a view showing a main part of the one-side coating application of the insulator slurry 102 to the current collector 101 using the electrode manufacturing apparatus. 9 (a) corresponds to a perspective view, and Fig. 9 (b) corresponds to a side view. 10 is a view showing a main part of a two-side application of the insulator slurry 102 to the current collector 101 using the electrode manufacturing apparatus. Fig. 10 (a) corresponds to a perspective view, and Fig. 10 (b) corresponds to a side view.

The electrode manufacturing apparatus according to the second embodiment is configured such that only the end portion of the current collector 101 is pressed by the protruding elastic body 55b in the insulator applying portion 50, Which is different from that of the electrode manufacturing apparatus 1 relating to the first embodiment.

In the second embodiment, the same reference numerals as in the first embodiment described above are used, and the same explanations are omitted.

First, the configuration of the insulator application portion 50 will be described with reference to Fig.

The elastic body 55b of the backup roll 55 for applying an insulator protrudes in the direction toward the current collector 101 so as to press only the end portion of the current collector 101. The insulator application portion 50 includes a backup roll 55 for applying an insulator in addition to the above-described application coating die 21 for applying an insulator, the liquid storage tank 22, the liquid delivery pump 23 and the liquid delivery pipe 24 .

The backup roll 55 for applying an insulator is pressed against the current collector 101 that is contacted by the application die 21 for applying an insulator from the opposite side. The backup roll 55 for applying an insulator is constituted by an axis 55a and an elastic body 55b. The axis 55a is made of, for example, metal and is formed into a columnar shape. The elastic body 55b partially covers the axis 55a. Specifically, the elastic body 55b is formed by covering a portion of the shaft center 55a coated with an adhesive with a rubber having a predetermined strength only at a portion opposed to the coating die 21 for applying an insulating material, And the outer side is uniformly polished to form a cylindrical shape. The backup roll 55 for applying an insulator is formed so that a cylindrical elastic body 55b is joined to both ends of a columnar shaft center 55a.

As the material of the elastic body 55b, diene rubber, natural rubber NR, isoprene rubber IR, butadiene rubber BR, styrene butadiene rubber SBR, chloroprene rubber CR, acrylonitrile butadiene rubber (NBR) , A silicone rubber or a urethane rubber is used. The material suitable for the elastic body 55b is, for example, a diene rubber. Diene rubbers use liquid paraffin as a plasticizer for adjusting the hardness. The liquid paraffin does not affect the characteristics of the battery even when it is transferred and adhered to the electrode material during the application process. Further, since the liquid paraffin has a low coefficient of friction, the electrode material can be lubricated and moved. That is, the liquid paraffin can be stably transported without generating wrinkles or the like on the electrode material.

The hardness of the rubber forming the elastic body 55b is selected from the range of A-10 to A-70 in " durometer A " specified in the new JIS standard. The hardness of the rubber is preferably in the range of A-20 to A-60. If the rubber hardness is too low, a sufficient repulsive force can not be obtained. On the other hand, if the rubber hardness is too high, the repulsive force is strong and the step between the insulating layer 102 'and the electrode layer 103' can not be sufficiently absorbed.

The upper limit value of the layer thickness of the elastic body 55b is set such that when the elastic body 55b is contracted by the tensile force of the current collector 101 in the one- 55b and the shaft center 55a have the same height. The lower limit value of the layer thickness of the elastic body 55b is specified under the condition that the thickness of the elastic layer 55b becomes thicker than the step between the insulating layer 102 'and the electrode layer 103' in the case of the double-side coating application. Specifically, the layer thickness of the elastic body 55b is, for example, 1 to 2 mm.

Next, the configurations of the one-side coating application and the two-side application using the insulator application portion 50 will be described with reference to Figs. 9 and 10. Fig.

In the single-sided coating application using the insulator application portion 50, Fig. 9 corresponds to the configuration of Fig. 6B in the above-described single-sided coating application. 9 shows a state in which the insulator slurry 102 is applied to the end portion of the current collector 101 by the coating die 21 for applying an insulator while the current collector 101 is being pressed by the backup roll 55 for applying an insulator As shown in FIG. The elastic body 55b of the backing roll 55 for applying an insulator shown in Fig. 9 largely contracts by itself at the contact portion with the current collector 101 so that the elastic body 55b and the shaft center 55a have the same height . Therefore, the single-sided coating can be performed while keeping the current collector 101 flat.

In the double-side coating application using the insulator application portion 50, Fig. 10 corresponds to the configuration of Fig. 7 (b) in the above-described both-side application. 10 shows a state in which the end of the current collector 101 is insulated from the end portion of the current collector 101 by the coating die 21 for applying an insulator while the current collector 101 is being pressed from the side coated with a single side by the backup roll 55 for applying an insulator. Shows a state in which the slurry 102 is applied. The elastic body 55b shown in Fig. 10 shrinks slightly at the portion in contact with the insulator layer 102 'so that the electrode layer 103' is formed and the portion having a relatively thicker layer and the insulator layer 102 ' ) Is formed so as to absorb the step generated at the boundary of the relatively thin layer thickness. Therefore, the current collector 101 can be prevented from being bent or refracted at the boundary between the portion where the electrode layer 103 'is formed and the portion where the insulator layer 102' is formed, even if the layer thickness is different.

The electrode manufacturing method according to the second embodiment and the electrode manufacturing apparatus embodying the electrode manufacturing method described above exhibit the following operational effects.

The elastic body 55b protrudes in the direction toward the current collector 101 and presses only the end portion of the current collector 101. [

According to this structure, as in Embodiment 1, the insulator slurry 102 can be applied without refracting or bending the current collector 101 at the time of double-side coating. Since the current collector 101 is not bent or bent, the dimensional accuracy of the current collector 101 is maintained, and shorting of the electrodes 100 can be prevented even when a plurality of electrodes 100 are laminated. In addition, it is possible to prevent the occurrence of pinholes in which air is entrained in the gap of the bent or bent portion.

When the current collector 101 is pressed by the back up roll 55 for applying an insulator, other than the end portion of the current collector 101, for example, the shape precision of the outer peripheral surface is high and sufficient It can be pressed through the metal shaft 55a having the hardness.

According to such a configuration, the backup roll 55 for applying an insulator can reduce the total amount of the elastic body 55b covering the shaft center 55a.

In addition, the present invention can be variously modified based on the constitution described in the claims, and they are also a category of the present invention.

1: electrode manufacturing apparatus
10, 1010:
11: Household full supply roll
12, 1012: drive roll
13, 1013:
14: Bringing roll
15: Export roll
16: Electrode winding roll
20, 50, 1020: insulator application portion
21, 1021: Application coating die for insulator application
22: Liquid storage tank
23: liquid pump
24:
25, 55, 1025: Backup roll for applying insulation
25a, 55a: axial center
25b, 55b: elastic body
30: Electrode application part
31: Electrode application coating die
32: Liquid storage tank
33: liquid pump
34:
35: backup roll for electrode application
40:
41: Housing
42: heater
43: Support roll
100: electrode
100a: Positive
100b: negative electrode
101: The whole house
101a: One side
101b: another side
102: insulator slurry
102 ': insulating layer
103: Electrode slurry
103 ': electrode layer
200: separator

Claims (9)

The insulating slurry applied to the end of one face of the current collector and the electrode slurry applied to the portion of the one face on which the insulator slurry is not coated are dried and pressed by the elastic body from the one face side An insulator applying step of applying the insulator slurry to an end of the other surface opposite to the one surface of the current collector;
And applying the electrode slurry to a portion of the other surface where the insulator slurry is not applied. The method according to claim 1,
The insulator slurry is applied to the current collector by the insulator coating step,
And the electrode slurry is applied to the current collector by the electrode coating step. 3. The method according to claim 1 or 2,
Further comprising a drying step of drying the insulator slurry applied to the current collector and the electrode slurry. 3. The method according to claim 1 or 2,
Wherein the insulator coating step is performed by applying the insulator slurry to the opposing ends of the current collector, respectively. 3. The method according to claim 1 or 2,
Further comprising a transporting step of transporting the current collector,
Wherein the insulator coating step applies the insulator slurry to either or both of the opposing ends along the conveying direction of the current collector. The insulating slurry applied to the end of one face of the current collector and the electrode slurry applied to the portion of the one face on which the insulator slurry is not coated are dried and pressed by the elastic body from the one face side An insulator applying portion for applying the insulator slurry to an end portion of the other surface opposite to the one surface of the current collector;
And an electrode applying unit for applying the electrode slurry to a portion of the other surface to which the insulator slurry is not applied. The method according to claim 6,
Wherein the thickness of the elastic body is thicker than the thickness of the electrode slurry after drying. 8. The method according to claim 6 or 7,
Wherein the elastic body protrudes in a direction toward the current collector and presses only the end of the current collector. 8. The method according to claim 6 or 7,
Wherein the elastic body is capable of being refracted.

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