Electrode cutting device

Abstract

To provide a cutting device of an electrode body which stably cuts off from each other a substance part and a lamination part of the electrode body to improve battery quality.SOLUTION: A cutting device 100 of an electrode body 1 comprises: a plurality of split tip-retainers 30 (31, 32); a plurality of split upper-blades 10 (11, 12A, 12B, 13A, 13B); a lower blade 20 not split; tip retainer adjustment means 50 which adjusts holding force of each of the tip retainers 30 (31, 32) for each of split portions of the tip retainers 30; and upper blade adjustment means 40 which adjusts height of each of the upper blades 10 (11, 12A, 12B, 13A, 13B) for each of split portions of the upper blades 10.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a cutting device for an electrode body.

Background Art

[0002] In an electrode body constituting a battery, after a negative electrode, a separator, and a positive electrode are sequentially coated on a substrate portion made of a metal foil to form a laminated portion, coating defects and lamination misalignments that occur at the end portion of the electrode body and do not function as a battery are removed to maximize battery performance.

[0003] The cutting device for an electrode body described in Patent Document 1 holds the electrode body placed on the lower blade with a pre-pressing portion, and cuts the electrode body by lowering the upper blade around the lower blade.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the cutting device for an electrode body described in Patent Document 1, the pressing force of the pre-pressing portion on the substrate portion and the laminated portion of the electrode body, and the clearance between the upper blade and the lower blade are made uniform, and they cannot cope with the thickness difference between the substrate portion and the laminated portion.

[0006] For this reason, the processing applied by the upper blade and the lower blade to the substrate portion and the laminated portion becomes unstable, and it is difficult to satisfy battery quality (no sag (interlayer contact), no burrs or chips, dimensional accuracy).

[0007] An object of the present invention is to stably cut the substrate portion and the laminated portion of the electrode body and improve battery quality.

Means for Solving the Problems

[0008] The invention according to claim 1 is an electrode cutting device comprising a plurality of divided tip-holding parts, a plurality of divided upper blades, an undivided lower blade, a tip-holding adjustment means for adjusting the pressing force of each tip-holding part at each divided portion of the tip-holding part, and an upper blade adjustment means for adjusting the height of each upper blade at each divided portion of the upper blade. [Effects of the Invention]

[0009] (a) By adjusting the clamping force of each clamping part at each divided portion of the clamping part using the pre-clamping adjustment means, the clamping force applied to each clamping part of the electrode body, which has a different thickness, can be adjusted. Therefore, the portions near the cutting points of the substrate and laminated parts of the electrode body can be securely restrained on the lower blade before the start of cutting. This suppresses movement of the substrate and laminated parts during cutting, allowing the upper and lower blades to stably cut the substrate and laminated parts and improve dimensional quality.

[0010] (b) By using multiple divided upper blades and an undivided lower blade, the clearance between the upper blades and the lower blades can be adjusted for substrate and laminated sections of the electrode body, which have different thicknesses. This allows for a smaller clearance for thinner sections (substrate sections) and a larger clearance for thicker sections (laminated sections), enabling stable cutting of the substrate and laminated sections by the upper and lower blades and improving battery quality.

[0011] (c) The upper blade adjustment means allows the height of each upper blade to be adjusted for each division of the upper blade, and a time difference can be introduced in the cutting timing of each upper blade for the substrate portion and the laminate portion of the electrode body, which have different thicknesses. This distributes the processing resistance that each upper blade receives from the electrode body over time, and the electrode body can be processed with low thrust.

[0012] (d) As described in (a) to (c) above, when cutting the substrate portion and laminate portion of the electrode body in a single step, the substrate portion and laminate portion can be cut stably with low thrust, thereby improving battery quality (no sagging (interlayer contact), no burrs or sharp edges, and dimensional accuracy). [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a schematic front view showing the cutting device. [Figure 2] Figure 2 shows the electrode body, where (A) is a plan view and (B) is a cross-sectional view. [Figure 3] Figure 3 is a schematic cross-sectional view showing the adjustment state of the pressing force applied to the substrate and laminated portions of the electrode body by the pre-pressing portion. [Figure 4] Figure 4 is a schematic plan view showing the adjustment state of the clearance between each of the multiple upper blades and the lower blade. [Figure 5] Figure 5 shows the cutting process of the cutting device, where (A) is a schematic front view showing the electrode body installation state, (B) is a schematic front view showing the pre-pressing state, and (C) is a schematic front view showing the cutting state by the upper and lower blades. [Modes for carrying out the invention]

[0014] Figure 1 shows a cutting device 100 according to one embodiment of the present invention, which has a punch holder 101 and a die holder 102 that are opposite each other vertically. The punch holder 101 is guided by a guide post 103 and moves up and down relative to the die holder 102 by obtaining a driving force such as hydraulic or electric force.

[0015] The cutting device 100 cuts the electrode body 1 that constitutes the battery, and has a plurality of divided upper blades 10 supported on the lower surface of the punch holder 101, an undivided lower blade 20 supported on the upper surface of the die holder 102, and a plurality of divided pre-pressing parts 30 provided on the lower surface of the punch holder 101. In this embodiment, the pre-pressing parts 30 allow the electrode body 1 held on the lower blade 20 to be cut by the upper blade 10.

[0016] The electrode body 1 is configured to have a substrate portion 2 and a laminated portion 3 as shown in FIG. 2, for example. The substrate portion 2 is formed from a metal foil such as aluminum, and the laminated portion 3 is formed by sequentially coating and laminating a powdery negative electrode 3A, a powdery separator 3B, and a powdery positive electrode 3C on the upper and lower surfaces of a part of the substrate portion 2.

[0017] As shown in FIG. 2, the electrode body 1 has a rectangular shape in plan view (FIG. 2(A)), with the substrate portion 2 and the laminated portion 3 having substantially the same width in the direction along the short side, the substrate portion 2 extending from one end side to the other end side along the long side, and the laminated portion 3 being formed in the range from the middle portion to the other end side along the long side. The substrate portion 2 has a film thickness ta of, for example, 10 μm, and the laminated portion 3 has a film thickness tb of, for example, 150 μm.

[0018] In order to remove coating defects and lamination misalignment of the laminated portion 3 (negative electrode 3A, separator 3B, positive electrode 3C) laminated on the substrate portion 2 and maximize battery performance, the outer edge portion of the electrode body 1 is cut by a cutting device 100.

[0019] As shown in FIGS. 1, 3, and 4, the cutting device 100 divides the upper blade 10 into an upper blade 11 for cutting the side of the laminated portion 3 of one of the short sides of the electrode body 1, upper blades 12A and 12B for cutting the substrate portion 2 and the laminated portion 3 respectively on one of the long sides of the electrode body 1, and upper blades 13A and 13B for cutting the substrate portion 2 and the laminated portion 3 respectively on the other long side of the electrode body 1.

[0020] At this time, the cutting device 100 has upper blade adjusting means 40 (not shown) for adjusting the height of each of the upper blades 11, 12A, 12B, 13A, and 13B for each of the above-described dividing portions of the upper blade 10.

[0021] That is, the cutting device 100 changes the protruding height of the upper blade 10 with respect to the lower blade 20 for each side of the electrode body 1. As shown in FIG. 1, the protruding height of the upper blade 11 is increased, the protruding heights of the upper blades 12A and 12B are set to intermediate values, and the protruding heights of the upper blades 13A and 13B are decreased. As a result, in a single descending operation of the punch holder 101, the cutting device 100 first cuts the laminated portion 3 of one of the short sides of the electrode body 1 with the upper blade 11, then cuts the substrate portion 2 and the laminated portion 3 on one of the long sides of the electrode body 1 with the upper blades 12A and 12B, and then cuts the substrate portion 2 and the laminated portion 3 on the other long side of the electrode body 1 with the upper blades 13A and 13B. As a result, each side of the electrode body 1 can be cut in the order of i, ii, and iii shown in FIG. 2(A).

[0022] The cutting device 100 has a plurality of divided upper blades 10 (upper blade 11, upper blades 12A and 12B, upper blades 13A and 13B) and an undivided lower blade 20, so that the clearance formed by each of the upper blades 11, 12A, 12B, 13A, and 13B with respect to the lower blade can be adjusted to an appropriate value according to the thickness of the cutting target. For example, as shown in FIG. 4, the clearance C1 of the upper blades 12A and 13A for cutting the substrate portion 2 with a small thickness with respect to the lower blade 20 is small, and the clearance C2 of the upper blades 12B and 13B for cutting the laminated portion 3 with a large thickness with respect to the lower blade 20 is set large (C1 < C2).

[0023] The cutting device 100 divides the pre-pressing portion 30 into a pre-pressing portion 31 that holds the substrate portion 2 of the electrode body 1 on the lower blade 20 and a pre-pressing portion 32 that holds the laminated portion 3 of the electrode body 1 on the lower blade 20.

[0024] At this time, the cutting device 100 has a pre-pressing adjustment means 50 that can adjust the pressing forces F1 and F2 (FIG. 3) applied by the respective pre-pressing portions 31 and 32 to the corresponding substrate portion 2 and laminated portion 3 to be independent of each other for each of the above-described divided portions of the pre-pressing portion 30.

[0025] The cutting device 100 cuts the electrode body 1 in a single cutting stroke according to the following (1) to (3) (FIG. 5).

[0026] (1) Place the electrode body 1 on the lower blade 20 (Figure 5(A)). After that, the punch holder 101 is lowered from its original position and the following cutting operation is performed.

[0027] (2) The front pressing portions 31 and 32 of the front pressing portion 30 press and hold the substrate portion 2 and the laminated portion 3 of the electrode body 1 against the lower blade 20, respectively (5(B)).

[0028] As shown in Figure 3, the front pressing portion 30 holds the substrate portion 2 with the pressing force F1 of the front pressing portion 31 and holds the laminated portion 3 with the pressing force F2 of the front pressing portion 32.

[0029] (3) The upper blades 11, 12A, 12B, 13A, and 13B of the upper blade 10 cut the substrate portion 2 and laminate portion 3 of the electrode body 1 in the order of i, ii, and iii (Figure 2(A)) described above (Figure 5(C)). In Figure 5(C), k represents the chips.

[0030] Therefore, according to this embodiment, the following effects and advantages are achieved. (a) By adjusting the clamping force of each clamping part 31, 32 at each divided portion of the clamping part 30 (31, 32) using the clamping adjustment means 50, the clamping force of each clamping part 31, 32 applied to the substrate part 2 and the laminated part 3, which have different thicknesses in the electrode body 1, can be adjusted. Accordingly, the portions of the substrate part 2 and the laminated part 3 of the electrode body 1 near the cutting points can be securely restrained on the lower blade 20 before the start of cutting. This suppresses movement of the substrate part 2 and the laminated part 3 during cutting, allowing the upper blade 10 and the lower blade 20 to stably cut the substrate part 2 and the laminated part 3, thereby improving dimensional quality.

[0031] (b) By using a plurality of divided upper blades 10 (11, 12A, 12B, 13A, 13B) and an undivided lower blade 20, the clearance between the upper blades 10 corresponding to the substrate portion 2 and the laminate portion 3 of the electrode body 1, which have different thicknesses, and the lower blade 20 can be adjusted. As a result, by setting a small clearance for the thin portion (substrate portion 2) and a large clearance for the thick portion (laminated portion 3), the upper blades 10 and lower blades 20 can stably cut the substrate portion 2 and the laminate portion 3, thereby improving battery quality.

[0032] (c) The upper blade adjustment means allows the height of each upper blade 10 (11, 12A, 12B, 13A, 13B) to be adjusted for each division of the upper blade 10, and a time difference can be introduced in the cutting timing of each upper blade 10 (11, 12A, 12B, 13A, 13B) for the substrate portion 2 and the laminated portion 3 of the electrode body 1, which have different thicknesses. This disperses the processing resistance that each upper blade 10 (11, 12A, 12B, 13A, 13B) receives from the electrode body 1 over time, and the electrode body 1 can be processed with low thrust.

[0033] (d) As described in (a) to (c) above, when cutting the substrate portion 2 and the laminated portion 3 of the electrode body 1 in a single step, the substrate portion 2 and the laminated portion 3 can be cut stably with low thrust, thereby improving battery quality (no sagging (interlayer contact), no burrs or sharp edges, and dimensional accuracy).

[0034] Although embodiments of the present invention have been described in detail with reference to the drawings above, the specific configuration of the present invention is not limited to these embodiments, and any design changes or other modifications that do not depart from the spirit of the present invention are also included in the present invention. [Industrial applicability]

[0035] According to the present invention, the substrate portion and the laminate portion of the electrode body can be stably cut, thereby improving battery quality. [Explanation of Symbols]

[0036] 1 Electrode body 10(11, 12A, 12B, 13A, 13B) Upper blade 20 Lower blade 30 (31, 32) Front retaining part 40 Upper blade adjustment means 50 Pre-pressure adjustment means 100 cutting equipment

Claims

[Claim 1] In an electrode cutting device, Multiple divided tip-holding parts, Multiple divided upper blades, The lower blade is not divided, A front-pressure adjustment means for adjusting the pressing force of each front-pressure part at each divided section of the front-pressure part, It has an upper blade adjustment means for adjusting the height of each upper blade at each divided section of the upper blade. An electrode cutting device characterized by the following features.

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