Battery electrode manufacturing apparatus and battery electrode manufacturing method

Abstract

To obtain a battery electrode manufacturing apparatus and battery electrode manufacturing method that can adjust the particle size distribution of the electrode slurry without using multiple types of slurries or multiple types of nozzles. [Solution] The battery electrode manufacturing apparatus is a battery electrode manufacturing apparatus that coats a current collector with a slurry containing an active material, and comprises a nozzle facing the current collector and discharging the slurry toward the current collector, and a plate laminate having a plurality of plates, each having a plurality of holes and stacked on top of each other, located between the current collector and the nozzle, and through which the slurry discharged from the nozzle toward the current collector passes, wherein the plate laminate is provided with a plurality of through holes that are connected to each other in the overlapping direction of the plurality of plates and penetrate the plate laminate, and through which the slurry passes, and the boundaries of two of the overlapping holes in the plurality of through holes are of a plurality of different sizes.

Description

Technical Field

[0001] The present invention relates to a battery electrode manufacturing apparatus and a battery electrode manufacturing method.

Background Art

[0002] Conventionally, an apparatus for manufacturing a battery electrode by applying a slurry containing an active material to the surface of a current collector is known (for example, Patent Document 1). Further, Patent Document 2 discloses a configuration in which a slit is made in a current collecting foil to adjust the current density.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Normally, since the particle size distribution of the electrode slurry is constant, there is a bias in the current density, and heat is partially generated during energization, and a bias in deterioration may occur. In contrast, it is necessary to prepare a plurality of types of slurries and a plurality of types of nozzles and adjust their combinations, which increases the labor and cost.

[0005] Therefore, one of the problems of the present invention is to obtain a battery electrode manufacturing apparatus and a battery electrode manufacturing method capable of adjusting the particle size distribution of the electrode slurry without using a plurality of types of slurries or a plurality of types of nozzles.

Means for Solving the Problems

[0006] The battery electrode manufacturing apparatus according to the present invention is a battery electrode manufacturing apparatus for coating a current collector with a slurry containing an active material, comprising: a nozzle facing the current collector and discharging the slurry toward the current collector; and a plate laminate having a plurality of plates, each having a plurality of holes and stacked on top of each other, located between the current collector and the nozzle, through which the slurry discharged from the nozzle toward the current collector passes, wherein the plate laminate is provided with a plurality of through holes formed by a plurality of holes that are connected to each other in the overlapping direction of the plurality of plates, and which penetrate the plate laminate and through which the slurry passes, and the boundaries between two of the overlapping holes in the plurality of through holes are of a plurality of different sizes.

[0007] With this configuration, the particle size distribution of the electrode slurry can be adjusted without using multiple types of slurries or multiple types of nozzles.

[0008] The battery electrode manufacturing apparatus includes, for example, a vibration device for vibrating the laminated plate body.

[0009] This configuration makes it possible to suppress clogging of the laminated plates.

[0010] The battery electrode manufacturing method according to the present invention is a battery electrode manufacturing method using the battery electrode manufacturing apparatus, comprising the steps of: the nozzle discharging the slurry toward the current collector; and the slurry discharged from the nozzle toward the current collector passing through the plate laminate.

[0011] With this configuration, the particle size distribution of the electrode slurry can be adjusted without using multiple types of slurries or multiple types of nozzles. [Effects of the Invention]

[0012] According to the present invention, a battery electrode manufacturing apparatus and a battery electrode manufacturing method can be obtained that can adjust the particle size distribution of the electrode slurry without using multiple types of slurries or multiple types of nozzles. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a perspective view schematically showing an electrode manufacturing apparatus for a battery according to the first embodiment. [Figure 2] Figure 2 is a plan view schematically showing an electrode for a battery according to the first embodiment. [Figure 3] Figure 3 is a cross-sectional view schematically showing a part of the electrode manufacturing apparatus for a battery according to the first embodiment. [Figure 4] Figure 4 is an enlarged view of part IV in Figure 3. [Figure 5] Figure 5 is a plan view schematically showing a plate laminate in the electrode manufacturing apparatus for a battery according to the first embodiment. [Figure 6] Figure 6 is a plan view schematically showing one of the plates in the plate laminate according to the first embodiment. [Figure 7] Figure 7 is an explanatory view for explaining the holes in one of the plates in the plate laminate according to the first embodiment. [Figure 8] Figure 8 is a plan view schematically showing the other plate in the plate laminate according to the first embodiment. [Figure 9] Figure 9 is an explanatory view for explaining the holes in the other plate in the plate laminate according to the first embodiment. [Figure 10] Figure 10 is a diagram schematically showing the battery according to the first embodiment. [Figure 11] Figure 11 is a diagram schematically showing the battery of the comparative example. [Figure 12] Figure 12 is a plan view schematically showing the plate laminate of the first modification of the first embodiment. [Figure 13] Figure 13 is a plan view schematically showing the plate laminate of the second modification of the first embodiment. [Figure 14] Figure 14 is a plan view schematically showing the first plate laminate in the electrode manufacturing apparatus for a battery according to the second embodiment. [Figure 15] Figure 15 is an exploded view schematically showing the first plate laminate in the electrode manufacturing apparatus for a battery according to the second embodiment. [Figure 16]FIG. 16 is a plan view schematically showing a second laminate in the battery electrode manufacturing apparatus of the second embodiment. [Figure 17] FIG. 17 is an exploded view schematically showing a second laminate in the battery electrode manufacturing apparatus of the second embodiment. [Figure 18] FIG. 18 is a plan view schematically showing a third laminate in the battery electrode manufacturing apparatus of the second embodiment. [Figure 19] FIG. 19 is an exploded view schematically showing a third laminate in the battery electrode manufacturing apparatus of the second embodiment. [Figure 20] FIG. 20 is a cross-sectional view schematically showing the lamination structure of the slurry in the second embodiment. [Figure 21] FIG. 21 is an explanatory view for explaining the lamination method of the slurry in the second embodiment.

Mode for Carrying Out the Invention

[0014] Hereinafter, embodiments of the battery electrode manufacturing apparatus according to the present invention will be described in detail with reference to the drawings. The following multiple embodiments include similar components. Those similar components are given common reference numerals, and redundant descriptions are omitted.

[0015] Also, the drawings are schematic, and the dimensional relationships of each element, the ratios of each element, etc. may be different from reality. Also, there may be parts where the dimensional relationships and ratios of each other are different even between the drawings.

[0016] <First Embodiment> FIG. 1 is a perspective view showing the battery electrode manufacturing apparatus of the first embodiment. As shown in FIG. 1, the battery electrode manufacturing apparatus 1 is an apparatus for manufacturing a battery electrode, and coats a slurry 50 containing an active material on a current collector 101. The battery electrode is, for example, an electrode for a secondary battery, and has a current collector 101 and a slurry coated on the surface of the current collector 101. The current collector is also referred to as a current collecting foil.

[0017] The battery electrode manufacturing apparatus 1 comprises a nozzle 3, a slurry supply device 4, a coating blade 5, a plate laminate 7, a vibration device 8, and a moving device (not shown). The nozzle 3, slurry supply device 4, coating blade 5, and plate laminate 7 constitute the coating section 9.

[0018] A slurry is a relatively viscous fluid. A slurry contains an active material, a solvent, and a binder. The active material, solvent, and binder are composed of known materials. The active material contains particles of various sizes.

[0019] The moving device is a device that moves the current collector 101 and the coated section 9 relative to each other. For example, the moving device supports the current collector 101 and moves the current collector 101 in a predetermined direction relative to the coated section 9. The moving device moves the current collector 101 using power from a power source such as a motor.

[0020] The slurry supply device 4 supplies slurry to the nozzle 3.

[0021] The nozzle 3 is positioned opposite the current collector 101. The nozzle 3 discharges the slurry 50 supplied by the slurry supply device 4 toward the current collector 101 (plate laminate 7).

[0022] The plate laminate 7 is located between the current collector 101 and the nozzle 3. The plate laminate 7 is a porous plate having multiple (for example, two) plates 11, 12, through which the slurry 50 discharged from the nozzle 3 and directed toward the current collector 101 can pass.

[0023] The coating blade 5 pushes the slurry 50, which is discharged by the nozzle 3 toward the current collector 101 and laminated on the plate laminate 7, into the plate laminate 7 and passes through it.

[0024] The vibration exciter 8 is connected to the plate laminate 7 and vibrates the plate laminate 7. The vibration exciter 8 has a vibrating element capable of generating vibrations.

[0025] In the above configuration, when the nozzle 3 discharges the slurry 50, the slurry 50 is deposited on the plate laminate 7. The slurry 50 on the plate laminate 7 is pushed into the plate laminate 7 by the coating blade 5, passes through the plate laminate 7, and is coated onto the current collector 101. At this time, the plate laminate 7 vibrates due to the vibration of the vibration device 8. In this way, the battery electrodes are manufactured.

[0026] Figure 2 is a schematic plan view showing a battery electrode according to the first embodiment. Figure 2 shows an example of a battery electrode 100 manufactured by the battery electrode manufacturing apparatus 1.

[0027] As shown in Figure 2, the battery electrode 100 comprises a current collector 101 (Figure 1) and a slurry layer 102 laminated on the surface of the current collector 101. The slurry layer 102 is composed of slurry 50.

[0028] The slurry layer 102 includes a low-resistance section and a high-resistance section. The low-resistance section is composed of slurry 50 in which the maximum particle size of multiple particles is a first particle size, and has relatively low electrical resistance. The high-resistance section is composed of slurry 50 in which the maximum particle size of multiple particles is a second particle size, which is larger than the first particle size, and has higher electrical resistance than the low-resistance section.

[0029] Furthermore, the slurry layer 102 has multiple (for example, two) regions 102a and 102b. The slurry layer 102 has, for example, a high-resistance portion along the boundary 102c between region 102a and region 102b. Of each region 102a and 102b, at least region 102a has a low-resistance portion. In this embodiment, for example, each region 102a and 102b has a low-resistance portion. That is, a low-resistance portion is provided in region 102a and at least region 102a of each region. Between the low-resistance portion of region 102a and the low-resistance portion of region 102b, a high-resistance portion is located along the boundary 102c.

[0030] The distribution of low-resistance and high-resistance regions in the slurry layer 102 described above is adjusted by the laminated plate 7. The laminated plate 7 will be described in detail below.

[0031] Figure 3 is a schematic cross-sectional view showing a part of the battery electrode manufacturing apparatus of the first embodiment. Figure 4 is an enlarged view of part IV of Figure 3. Figure 5 is a schematic plan view showing the plate laminate in the battery electrode manufacturing apparatus of the first embodiment. Figure 6 is a schematic plan view showing one plate in the plate laminate of the first embodiment. Figure 7 is an explanatory diagram for illustrating the holes in one plate in the plate laminate of the first embodiment. Figure 8 is a schematic plan view showing the other plate in the plate laminate of the first embodiment. Figure 9 is an explanatory diagram for illustrating the holes in the other plate in the plate laminate of the first embodiment.

[0032] As shown in Figures 3-7, each of the multiple plates 11 and 12 in the laminated plate structure 7 has multiple holes 11a and 12a. In Figure 5, the plates 11 and 12 are colored gray to make the overlap of the holes 11a and 12a easier to see. The laminated plate structure 7 has multiple through holes 7a. The multiple through holes 7a are composed of multiple holes 11a and 12a that are connected to each other in the overlapping direction of the multiple plates 11 and 12, and penetrate the laminated plate structure 7. As shown in Figures 3 and 4, the slurry 50 passes through the multiple through holes 7a.

[0033] As shown in Figures 4 and 5, the boundary portions 7b of two overlapping holes 11a and 12a in the multiple through holes 7a have multiple different sizes. That is, there are multiple boundary portions 7b of different sizes. In other words, the minimum cross-sectional areas of the multiple through holes 7a have multiple different sizes. That is, at least two of the multiple through holes 7a have different minimum cross-sectional areas. To put it another way, the area of ​​the overlapping portion of the plates 11 and 12 in the overlapping direction in the two holes 11a and 12a has multiple sizes in plan view. The part of the through hole 7a with the minimum cross-sectional area is the narrowest part of the through hole 7a. The cross-sectional area of ​​the through hole 7a is the area of ​​the cross section perpendicular to the direction in which the through hole 7a penetrates the plate laminate 7 (the overlapping direction of the plates 11 and 12). With the above configuration, it is possible to form low-resistance and high-resistance sections.

[0034] As shown in Figure 6, the plate 12 is provided with a plurality of holes 12a. The plurality of holes 12a penetrate the plate 12 in the thickness direction of the plate 12.

[0035] Here, Figure 6 and others show the X and Y directions. The X and Y directions are orthogonal to each other. The X direction follows the first width direction of the laminated plate 7. The Y direction follows the second width direction of the laminated plate 7, which is orthogonal to the first width direction.

[0036] As shown in Figures 6 and 7, the plate 12 has multiple rows of holes C arranged in the Y direction, each consisting of multiple holes 12a arranged in the X direction. As shown in Figure 7, two adjacent holes 12a in a row of holes are spaced L1 apart. Also, two adjacent rows of holes are spaced L2 apart. Furthermore, the diameter L3 in the X direction of the hole 12a and the diameter L14 in the Y direction of the hole 12a are the same.

[0037] As shown in Figure 8, the plate 11 is provided with a plurality of holes 11a. The plurality of holes 11a penetrate the plate 12 in the thickness direction of the plate 11. The plurality of holes 11a are arranged in a matrix. The plate 11 is provided with a plurality of regions R1 to R4.

[0038] The arrangement and shape of the holes 11a in region R1 are the same as those in plate 12. The arrangement and shape of the holes 11a in regions R2, R3, and R4 are obtained by changing the spacing L1, L2 and diameters L3, L14 in plate 12 by a predetermined magnification.

[0039] As shown in Figure 9, in the hole rows of regions R2 to R4, two adjacent holes 11a are spaced L11 apart. Also, two adjacent hole rows are spaced L12 apart. Furthermore, the diameter L13 in the X direction of hole 11a and the diameter L14 in the Y direction of hole 11a are different.

[0040] Here, α and β are defined as follows. α= Interval L11 / Interval L1=Diameter L13 / Diameter L3 β= Interval L12 / Interval L2=Diameter L14 / Diameter L4 In this case, in regions R2 and R4, for example, α=β=1.1. Also, in region R3, for example, α=1 and β=0.75. Note that the values ​​of α and β in regions R2 to R4 are not limited to those above.

[0041] Next, the battery of this embodiment will be described in comparison with the battery of the comparative example. Figure 10 is a schematic diagram showing the battery of the first embodiment. Figure 11 is a schematic diagram showing the battery of the comparative example.

[0042] As shown in Figure 10, the battery 110 of this embodiment has a battery electrode 100 manufactured by the battery electrode manufacturing apparatus 1, a positive electrode tab 103, and a negative electrode tab 104. On the other hand, the comparative example battery 210 has a battery electrode 200, a positive electrode tab 103, and a negative electrode tab 104. The comparative example battery electrode 200 has a uniform particle size distribution in the slurry layer. The arrows in Figures 10 and 11 schematically show the path of current flow. The thickness of the lines in each arrow schematically represents the magnitude of the current, with thicker lines indicating a larger current flow. As can be seen from Figures 10 and 11, in the comparative example battery electrode 200, a larger current flows closer to the positive electrode tab 103 and the negative electrode tab 104. That is, in the comparative example battery electrode 200, an uneven distribution of current density occurs, causing significant localized heat generation when energized, and resulting in uneven degradation of the battery electrode 200 within the battery 210. In contrast, the battery electrode 100 of this embodiment has a more uniform current flow compared to the comparative example. That is, the current density of the battery electrode 100 of this embodiment is more uniform compared to the comparative example. This is because the battery electrode 100 is provided with a high-resistance section. As a result, the battery electrode 100 of this embodiment is less likely to generate excessive heat in certain areas, less likely to have an uneven current density, and less likely to generate excessive heat in certain areas when energized. Therefore, uneven degradation of the battery electrode 100 within the battery 110 is suppressed.

[0043] As described above, the battery electrode manufacturing apparatus 1 of this embodiment coats the current collector 101 with a slurry 50 containing an active material. The battery electrode manufacturing apparatus 1 comprises a nozzle 3 and a plate laminate 7. The nozzle 3 faces the current collector 101 and discharges the slurry 50 toward the current collector 101. The plate laminate 7 is located between the current collector 101 and the nozzle 3. The plate laminate 7 has a plurality of plates 11, 12, through which the slurry 50 discharged from the nozzle 3 toward the current collector 101 passes. Multiple plates 11 and 12 are stacked on top of each other, each having multiple holes 11a and 12a. The plate laminate 7 has multiple through holes 7a. The multiple through holes 7a are formed by multiple holes 11a and 12a that are connected to each other in the overlapping direction of the multiple plates 11 and 12, and penetrate the plate laminate 7. Slurry 50 passes through the multiple through holes 7a. The boundary portions 7b of two overlapping holes 11a and 12a in the multiple through holes 7a have multiple different sizes.

[0044] With this configuration, the particle size distribution of the electrode slurry 50 can be adjusted without using multiple types of slurry 50 or multiple types of nozzles 3. That is, by placing multiple plates 11 and 12 between the nozzle 3 and the current collector 101, the particle size of the active material can be controlled by the size of the through-holes 7a when the multiple plates 11 and 12 are stacked. Therefore, even with a slurry that has a constant particle size distribution, the particle size distribution when coated can be adjusted. Thus, the particle size distribution can be optimized. In addition, since there is no need to prepare multiple types of slurry 50 or multiple types of nozzles 3, the cost of manufacturing battery electrodes and the battery electrode manufacturing apparatus 1 can be reduced. Furthermore, by stacking two plates 11 and 12, it is possible to create through-holes 7a with a minimum cross-sectional area smaller than the holes 11a and 12a of each plate 11 and 12. Also, in Patent Document 2, it is necessary to make slits in the current collector foil, i.e., the current collector, but in this embodiment, it is not necessary to make such slits.

[0045] Furthermore, the battery electrode manufacturing apparatus 1 is equipped with a vibration device 8 that vibrates the laminated plate body 7.

[0046] This configuration makes it possible to suppress clogging of the laminated plate body 7.

[0047] Furthermore, the battery electrode manufacturing method uses the battery electrode manufacturing apparatus 1. The battery electrode manufacturing method includes the steps of a nozzle 3 discharging slurry 50 toward a current collector 101, and the steps of the slurry 50 discharged from the nozzle 3 toward the current collector 101 passing through a plate laminate 7.

[0048] With this configuration, the particle size distribution of the electrode slurry 50 can be adjusted without using multiple types of slurry 50 or multiple types of nozzles 3.

[0049] Note that the laminated plate 7 is not limited to those described above. Here, Figure 12 is a schematic plan view showing a laminated plate of a first modified example of the first embodiment. Figure 13 is a schematic plan view showing a laminated plate of a second modified example of the first embodiment. The laminated plate 7 may have the shape shown in Figures 12 and 13.

[0050] <Second Embodiment> Figure 14 is a schematic plan view showing the first plate laminate in the battery electrode manufacturing apparatus of the second embodiment. Figure 15 is a schematic exploded view showing the first plate laminate in the battery electrode manufacturing apparatus of the second embodiment. Figure 16 is a schematic plan view showing the second plate laminate in the battery electrode manufacturing apparatus of the second embodiment. Figure 17 is a schematic exploded view showing the second plate laminate in the battery electrode manufacturing apparatus of the second embodiment. Figure 18 is a schematic plan view showing the third plate laminate in the battery electrode manufacturing apparatus of the second embodiment. Figure 19 is a schematic exploded view showing the third plate laminate in the battery electrode manufacturing apparatus of the second embodiment. Figure 20 is a schematic cross-sectional view showing the slurry laminate structure of the second embodiment. Figure 21 is an explanatory diagram for explaining the slurry laminate method of the second embodiment.

[0051] As shown in Figures 14 to 19, this embodiment differs from the first embodiment in that the battery electrode manufacturing apparatus 1 comprises a plurality of plate laminates 7. The plurality of plate laminates 7 are the first plate laminate 7A (Figures 14 and 15), the second plate laminate 7B (Figures 16 and 17), and the third plate laminate 7C (Figures 18 and 19).

[0052] The plates 12 of the first laminated plate 7A (Figure 15), the plates 12 of the second laminated plate 7B (Figure 17), and the plates 12 of the third laminated plate 7C (Figure 19) are all the same shape.

[0053] The plate 11 of the first laminated plate 7A (Figure 15) has the same shape as plate 12. The plate 11 of the second laminated plate 7B (Figure 17) has a shape that is larger than plate 12 in both the X and Y directions by the same magnification. The plate 11 of the third laminated plate 7C (Figure 19) has a shape that is modified from plate 12 in both the X and Y directions by different magnifications.

[0054] In this embodiment, the battery electrode manufacturing apparatus 1 is capable of switching between a first plate laminate 7A, a second plate laminate 7B, and a third plate laminate 7C as the plate laminate 7 used. Depending on the particle size distribution of the slurry layer 102 to be manufactured, the first plate laminate 7A, the second plate laminate 7B, and the third plate laminate 7C are selectively used. Furthermore, in this embodiment, the battery electrode manufacturing apparatus 1 has a moving mechanism that moves a plurality of plates 11, 12 in each plate laminate 7 in a direction perpendicular to the overlapping direction of the plates 11, 12. The moving mechanism moves the plates 11, 12 relative to each other using power from a power source such as a motor.

[0055] As shown in Figure 20, in this embodiment, for example, the three-dimensional particle size distribution in the slurry layer 102 is not uniform and changes. The Z direction in Figure 20 is perpendicular to the X and Y directions. Parts D1 to D4 in Figure 20 can be made by the plate laminate 7 in states d1 to d4 in Figure 21.

[0056] As described above, the multiple laminated plates 7 may have the same or different sizes and shapes (i.e., different textures) of the holes 11a and 12a. Furthermore, the coating process may be performed while moving the laminated plates 7. Additionally, the laminated plates 7 may be rearranged or moved to increase the particle size in areas where current is concentrated on the battery electrodes 100. Moreover, by repeatedly coating while moving the laminated plates 7, the particle size distribution in the thickness direction of the slurry layer 102 can also be controlled.

[0057] The battery electrode manufacturing apparatus 1 may use only one of the following as the laminated plate body 7: the first laminated plate body 7A, the second laminated plate body 7B, and the third laminated plate body 7C.

[0058] The above embodiments illustrate examples of the present invention, but these embodiments are merely examples and are not intended to limit the scope of the invention. The above embodiments can be implemented in various other forms, and various omissions, substitutions, combinations, and modifications can be made without departing from the spirit of the invention. The above embodiments are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0059] 1... Battery electrode manufacturing apparatus, 3... Nozzle, 7... Plate laminate, 7a... Through hole, 7b... Boundary section, 11, 12... Plate, 11a, 12a... Hole, 50... Slurry, 101... Current collector.

Claims

1. A battery electrode manufacturing apparatus for coating a current collector with a slurry containing an active material, A nozzle facing the current collector and discharging the slurry toward the current collector, A plate laminate having multiple plates, each with multiple holes, stacked on top of each other, located between the current collector and the nozzle, through which the slurry discharged from the nozzle and directed toward the current collector passes, Equipped with, The laminated plate body is provided with multiple through-holes, which are formed by multiple holes that are connected to each other in the overlapping direction of the multiple plates, and which penetrate the laminated plate body through which the slurry passes. In the aforementioned plurality of through holes, the boundary between two overlapping holes has multiple different sizes. Battery electrode manufacturing equipment.

2. The system includes a vibration device that vibrates the aforementioned laminated plate body. The apparatus for manufacturing electrodes for batteries according to claim 1.

3. A method for manufacturing battery electrodes using the battery electrode manufacturing apparatus described in claim 1 or claim 2, The process involves the nozzle discharging the slurry toward the current collector, The process involves the slurry discharged from the nozzle and directed toward the current collector passing through the laminated plate, A method for manufacturing battery electrodes, including the aforementioned method.

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