JP2018026334A - Electrode of power storage device, manufacturing apparatus of electrode and manufacturing method of electrode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the electrode of a power storage device capable of suppressing battery performance degradation, and to provide a manufacturing apparatus of an electrode and a manufacturing method of an electrode.SOLUTION: A roll press device 40 includes a first press roller 41 and a second press roller 45. First pressure roller 42 of the first press roller 41 includes a first protrusion 42a at a position facing a portion becoming the first marginal part 12a of an active material layer in a coating part 16. Furthermore, the first pressure roller 42 includes a second protrusion 42c at a position facing a portion becoming the second marginal part 12b of an active material layer in the coating part 16. The roller body 47 of the second pressure roller 46 of the second press roller 45 has a cam shape, and a third protrusion 47a. The third protrusion 47a includes a third pressing surface 47b for pressing a portion becoming the third marginal part 12c of the active material layer and a blade 48.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an electrode of a power storage device, an electrode manufacturing apparatus, and an electrode manufacturing method.

  Conventionally, vehicles such as EVs (Electric Vehicles) and PHVs (Plug-in Hybrid Vehicles) have been mounted with lithium-ion secondary batteries or nickel-hydrogen secondary batteries as power storage devices that store the power supplied to the motor for travel. ing. The basic structure of a battery is a power generation element (electrode assembly) in a stacked state in which a strip-shaped separator is sandwiched between a positive electrode and a negative electrode coated (supported) with an active material on a metal current collector plate. The power generation element is housed in the battery case together with the electrolytic solution. Then, by increasing the amount of the active material applied to the current collector plate, it is possible to increase the battery performance output (the value obtained by multiplying the discharge current by the discharge voltage).

  As shown in FIGS. 8A to 8C, as an electrode manufacturing method, for example, Patent Document 1 includes an electrode sheet 60 in which an active material layer 62 is formed on a long metal foil 61. A method of manufacturing the electrode 69 by cutting it into a rectangular shape with a punching machine has been proposed. In the electrode manufacturing method disclosed in Patent Document 1, first, the electrode sheet 60 is cut along a two-dot chain line 63 as shown in FIG. Then, as shown in FIG. 8B, a rectangular electrode sheet 64 is formed. Further, the rectangular electrode sheet 64 is cut along two-dot chain lines 65, 66, 67, 68 by a punching machine (not shown). As a result, the electrode 69 is manufactured as shown in FIG.

  In addition, as a method for manufacturing an electrode assembly, for example, as in Patent Document 2, a sheet-like body (electrode) is dropped at a predetermined position using gravity, and the sheet-like body is sequentially given by a guide laminating means. A method of laminating by guiding the arrangement has been proposed.

  As shown in FIG. 9, the manufacturing apparatus 70 of the laminated body 72 which laminates | stacks the sheet-like body 71 which performs said manufacturing method is the supply mechanism 76 which supplies several sheet-like bodies 71, and the supplied sheet-like form A drop moving means 73 for dropping the body 71 to a predetermined position using gravity, and a guide stacking means 75 for sequentially guiding and stacking the dropped sheet-like bodies 71 to a predetermined arrangement are provided. The guide laminating means 75 includes a bottom wall and a standing wall. The bottom wall and the standing wall are guided and positioned in a predetermined position by stopping the movement of the sheet-like body 71 that has been dropped to a predetermined position by the drop moving means 73, and the sheet-like body 71 is aligned with the wall surface of the standing wall. The laminated body 72 is manufactured by guiding the laminated body in a predetermined direction.

Japanese Unexamined Patent Publication No. 2016-1000028 JP 2012-91372 A

  However, when the electrode (sheet-like body 71) is stacked using the manufacturing apparatus 70 described in Patent Document 2, the electrode edge contacts the guide stacking means 75 while the electrode is falling or during positioning. In the electrode edge, there is a possibility that defects such as falling (powder off) of active material particles from the applied active material and peeling of the active material from the metal foil may occur. When powder fall or peeling occurs, it causes a decrease in battery performance.

  The present invention has been made paying attention to such problems existing in the prior art, and the object thereof is an electrode of a power storage device, an electrode manufacturing apparatus, and an electrode manufacturing method capable of suppressing a decrease in battery performance. Is to provide.

  An electrode manufacturing apparatus for solving the above-described problem is that at least a plurality of electrodes used in a stacked manner are coated with an active material mixture and an uncoated portion where the active material mixture is not applied Is an electrode manufacturing apparatus for pressing and cutting the coated portion in the electrode material formed in a line in the short direction of the strip-shaped current collector and continuously in the longitudinal direction. A transport device for transporting the current collector in the longitudinal direction of the strip current collector; and a press roller installed in a transport path of the strip current collector by the transport device and extending in a short direction of the strip current collector; And the press roller protrudes from the pressing surface and has a pressing portion that presses an edge of a region to be an active material mixture coating portion on the electrode, and the belt-shaped current collector And a blade portion extending over the entire short direction of That.

  According to this, the edge part of the area | region used as the coating part in an electrode can be pressed with the pressing surface of a press roller, conveying a strip | belt-shaped collector in the longitudinal direction of this strip | belt-shaped collector. The pressed edge has higher adhesion to the current collector than before pressing. Further, the blade portion can be pressed and cut while transporting the belt-like current collector. Therefore, when laminating a plurality of obtained electrodes, even if the electrode is in the middle of falling or positioning, even if the electrode edge contacts a positioning jig or the like, powder fall off or peeling off from the electrode edge It is difficult to occur, and battery performance degradation of the obtained power storage device can be suppressed. In addition, productivity can be improved as compared with the case where conveyance is stopped and moved each time cutting is performed, and an electrode capable of suppressing loss of electrode edge portions when a plurality of electrodes are stacked can be manufactured.

In the electrode manufacturing apparatus, the protruding portion may press at least an edge portion of the region to be the coated portion, excluding the edge portion on the uncoated portion side.
According to this, at the time of laminating a plurality of electrodes, rather than dropping the electrode from the uncoated part side, the electrode may be dropped from either side of the remaining three side edges excluding the uncoated part side. Many. At this time, the remaining three edges are more likely to come into contact with a positioning jig or the like during the dropping of the electrode or at the time of positioning compared to the edge on the uncoated part side. Due to the high nature, the electrode edge is not easily damaged.

  Further, in the electrode manufacturing apparatus, the press roller is at least the opposite side among an edge portion on the uncoated portion side and an edge portion opposite to the edge portion in the region to be the coated portion. A first press roller that presses the edge, and a second press that presses the edge excluding the edge on the uncoated part side and the edge on the opposite side in the area to be the coated part. And a roller.

  According to this, by dividing the press roller into the first press roller and the second press roller, the shape of the protruding portion and the blade portion can be simplified, and the design of each press roller can be simplified.

  In the electrode manufacturing apparatus, the second press roller has a cam shape, and includes the same diameter portion and the protruding portion having a larger diameter than the same diameter portion. You may have the said blade part in the position of the largest diameter.

  According to this, since the second press roller has a cam shape, the pressing surface is a curved surface, and the edge of the region that becomes the coating portion on the electrode can be gradually pressed by the pressing surface. . Therefore, when pressing the edge of the region to be the coating portion on the electrode, wrinkles are unlikely to occur in the band-shaped current collector.

In the electrode manufacturing apparatus, the second press roller may have a gear shape having a plurality of protruding portions in the circumferential direction, and the blade portion may be provided at a central portion of the protruding portion. .
According to this, only the edge part of the area | region used as the coating part in an electrode can be pressed by the protrusion part. Therefore, the part that presses the edge of the region that becomes the coating part in the electrode suppresses the decrease in the gap of the entire electrode and maintains the amount of electrolyte impregnated inside the electrode even if the active material filling density is increased by pressing. Thus, the electrochemical reaction of the electrode can be satisfactorily caused and the output of the battery performance can be ensured.

  An electrode manufacturing method for solving the above-described problem is that at least a plurality of electrodes used in a stacked manner are coated with an active material mixture and an uncoated portion where the active material mixture is not applied Is an electrode manufacturing method for manufacturing by pressing and cutting the coated portion in the electrode material formed in the short direction of the strip-shaped current collector and continuously formed in the longitudinal direction, Edges excluding at least the uncoated portion side of the region of the strip current collector that is the coating portion of the electrode while transporting the electrical conductor in the longitudinal direction of the strip current collector And a cutting step of cutting the electrode material along the short direction of the belt-like current collector in the course of the pressing step.

  According to this, the edge part of the area | region used as the coating part in an electrode can be pressed, conveying a strip | belt-shaped collector in the longitudinal direction of this strip | belt-shaped collector by a press process. The pressed edge has higher adhesion to the current collector than before pressing. Moreover, it can press and cut | disconnect a strip | belt-shaped electrical power collector according to a cutting process. Therefore, when laminating a plurality of obtained electrodes, even if the electrode is in the middle of falling or positioning, even if the electrode edge contacts a positioning jig or the like, powder fall off or peeling off from the electrode edge It is difficult to occur, and battery performance degradation of the obtained power storage device can be suppressed. In addition, productivity can be improved as compared with the case where conveyance is stopped and moved each time cutting is performed, and an electrode capable of suppressing loss of electrode edge portions when a plurality of electrodes are stacked can be manufactured.

  Further, in the above-described electrode manufacturing method, the pressing step is at least the opposite side among the edge portion on the uncoated portion side in the region to be the coated portion and the opposite edge portion of the edge portion. A first pressing step for pressing the edge, and an edge excluding the edge on the uncoated portion side and the edge on the opposite side in the region to be the coated portion after the first pressing step. A second pressing step of pressing, and the cutting step is performed in the process of the second pressing step.

According to this, a cutting process cut | disconnects in the process of a 2nd press process, pressing the part used as the edge part of a coating part. For this reason, the strip-shaped current collector can be cut into individual pieces.
An electrode manufacturing apparatus for solving the above problems is a transport device that transports a strip electrode having a coating portion in which an active material mixture is applied to the surface of the strip collector in the longitudinal direction of the strip electrode; It is a columnar body having a short axis direction of the belt-like electrode as a rotation axis, a first press roller for pressing the longitudinal direction of the belt-like electrode, and a columnar body having a short axis direction of the belt-like electrode as a rotation axis. A second press roller that presses the short-side direction of the belt-like electrode, wherein the first press roller has a shaft portion and a first diameter larger than that of the shaft portion. 1 press part, the 1st press part is arranged in the position which presses the edge of the longitudinal direction of the application part, and the 2nd press roller has the same diameter part and the same diameter A second pressing portion having a larger diameter than the portion, and the second pressing portion is positioned at the maximum diameter in the short side. And summarized in that a blade portion extending in direction.

  An electrode of a power storage device for solving the above problems includes a rectangular active material layer in which an active material mixture is applied to at least one surface of a current collector, and an uncoated surface in which the surface of the current collector is exposed. The active material layer has a general part and an edge, and the edge is at least partially adjacent to the uncoated part, and the first edge. A second edge located opposite to the portion, and a pair of third edges connecting the first edge and the second edge, at least the second edge and the The gist is that the third edge portion has a thickness of the active material layer thinner than that of the general portion, and the third edge portion has a tapered shape with a smaller thickness toward the end of the current collector. To do.

  ADVANTAGE OF THE INVENTION According to this invention, the electrode of the electrical storage apparatus which can suppress the fall of battery performance, the manufacturing apparatus of an electrode, and the manufacturing method of an electrode can be provided.

The perspective view of the electrode manufactured by the manufacturing apparatus of an embodiment. Schematic of the manufacturing apparatus of the electrode which concerns on embodiment. The perspective view which shows the 1st press roller and 2nd press roller used for the manufacturing apparatus of embodiment. The side view which shows the 1st press roller and 2nd press roller which are used for the manufacturing apparatus of embodiment. (A)-(e) is explanatory drawing explaining the press process and cutting process of an electrode material by a 2nd press roller. The schematic diagram which shows the punching part of the electrode material by a punching apparatus. The perspective view which shows another example of a 2nd press roller. (A)-(c) is a figure which shows background art. The figure which shows background art.

  Hereinafter, referring to FIG. 1 to FIG. 6, an embodiment in which the electrode of the power storage device, the electrode manufacturing apparatus, and the electrode manufacturing method are embodied in the secondary battery electrode, the secondary battery electrode manufacturing apparatus, and the manufacturing method will be described. To explain.

  Although not shown, the secondary battery as a power storage device using the electrode manufactured by the manufacturing method using the manufacturing apparatus of this embodiment is a rectangular battery having a rectangular external appearance, and is a lithium ion secondary battery. is there. This secondary battery includes an electrode assembly in a case. The electrode assembly includes a plurality of positive electrodes and a plurality of negative electrodes. The electrode assembly is configured by alternately laminating positive electrodes and negative electrodes in a state where they are insulated by a separator.

  As shown in FIG. 1, the electrode 10 used in the secondary battery includes a metal foil 11 as a current collector and a rectangular active material layer 12 present on the surface (both surfaces) of the metal foil 11. The electrode 10 has an uncoated portion 13 where the surface of the metal foil 11 is exposed along one side thereof. The electrode 10 has a current collecting tab 14 having a shape protruding from a part of the uncoated portion 13. The active material layer 12 has a portion other than the edge portion and the edge portion as a general portion. The edge includes the first edge 12a on the uncoated part 13 side, the second edge 12b located on the opposite side of the first edge 12a, the first edge 12a, and the second edge. And a third edge portion 12c excluding 12b. In other words, the first edge portion 12a is adjacent to the uncoated portion 13, and the pair of third edge portions 12c connects the first edge portion 12a and the second edge portion 12b. In the electrode 10, the direction along the first edge 12a and the second edge 12b is defined as the longitudinal direction, and the direction along the third edge 12c is defined as the short direction. Each edge part 12a, 12b, 12c is pressed strongly compared with parts other than the edge part in each active material layer 12, and a film thickness is smaller than parts other than an edge part. Further, the third edge portion 12 c has a taper shape in which the film thickness decreases toward the end portion in the longitudinal direction of the metal foil 11 in each active material layer 12.

Next, a method for manufacturing the electrode 10 will be described.
As shown in FIG. 2, the manufacturing method of the electrode 10 includes a transporting process for transporting the strip-shaped current collector 15, and a coating process for coating the active material mixture on the surface of the strip-shaped current collector 15 to form a coating portion 16. And a drying process for drying the coating part 16 and a rolling process for rolling the coating part 16. Furthermore, the manufacturing method of the electrode 10 includes a pressing step of pressing the portions to be the edge portions 12a, 12b, and 12c of the active material layer 12 in each coating portion 16, and a strip-shaped current collector along the third edge portion 12c. A cutting step of cutting the body 15 and the coating part 16 is included. Note that the active material layer 12 of the electrode 10 is a region that becomes the coating portion 16 of the active material mixture in the electrode 10. Furthermore, the manufacturing method of the electrode 10 includes a punching process in which the cut strip-shaped current collector 15 and the coating portion 16 are punched into the shape of the electrode 10.

  The electrode 10 is manufactured by the electrode manufacturing apparatus 20. The manufacturing apparatus 20 includes a transport device 30 that performs a transport process, a coating device 33 that performs a coating process, a drying device 36 that performs a drying process, and a rolling device 37 that performs a rolling process. Furthermore, the manufacturing apparatus 20 includes a roll press device 40 that performs a pressing step and a cutting step, and a punching device 38 that performs a punching step.

  The transport device 30 includes a supply reel 31 around which the belt-like current collector 15 is wound, and a plurality of guide rolls 32. The strip-shaped current collector 15 is fed from the supply reel 31 and then conveyed toward the coating device 33 through the guide roll 32. The coating device 33 includes a die head 34 and a back roller 35. The die head 34 includes a manifold 34a and a nozzle 34b. The active material mixture produced by the kneading step (not shown) is supplied to the manifold 34a. Thereafter, the active material mixture is extruded from the manifold 34 a to the nozzle 34 b and applied to the strip-shaped current collector 15. Note that FIG. 2 shows a state in which the coating portion 16 has already been formed on one surface (lower surface) of the strip-shaped current collector 15 and the active material mixture has been applied to the other surface.

  The strip-shaped current collector 15 to which the active material mixture is applied is supplied to the drying process via the guide roll 32. The active material mixture applied to the strip-shaped current collector 15 is dried by the drying device 36 to form the coating part 16.

  As shown in FIG. 3, the strip-shaped current collector 15 includes an exposed portion 17 in a portion where the coating portion 16 is not formed and the metal foil 11 is exposed. The coating part 16 and the exposed part 17 are arranged in the short direction of the strip-shaped current collector 15 and are continuously formed in the longitudinal direction. An electrode material 18 as a band electrode is formed from the band current collector 15 and the coating portion 16. The coating part 16 includes a region 16 a that becomes the active material layer 12 in the electrode 10.

  As shown in FIG. 2, the electrode material 18 is subjected to a rolling process. The rolling device 37 includes rolling rollers 37a and 37b. Each coating part 16 is rolled because the electrode material 18 passes between the rolling rollers 37a and 37b.

  The electrode material 18 that has undergone the rolling process is subjected to a pressing process and a cutting process. As the electrode material 18 passes through the roll press device 40, the portions to be the edges 12a, 12b, and 12c of the active material layer 12 in each coating portion 16 are pressed and become the third edge 12c. Cut along the part.

  The electrode material 18 cut into a rectangular shape is subjected to a punching process. As shown in FIG. 6, the cut electrode material 18 is punched along a two-dot chain line 54 by a punching device 38. Then, the uncoated part 13 and the current collection tab 14 are formed from the exposed part 17, and the electrode 10 is manufactured.

  Among the above six apparatuses, other apparatuses except the roll press apparatus 40, that is, the conveying apparatus 30, the coating apparatus 33, the drying apparatus 36, the rolling apparatus 37, and the punching apparatus 38 are basically the same as the conventional electrode manufacturing apparatus. In the following, the roll press device 40 will be mainly described.

  As shown in FIG. 3 and FIG. 4, the roll press device 40 is configured to press a portion that becomes the first edge portion 12 a and the second edge portion 12 b of each active material layer 12 in each coating portion 16. Perform the process. In addition, the roll press device 40 presses the electrode material 18 in the course of the second pressing step and the second pressing step that press the portion that becomes the third edge portion 12c of the both active material layers 12 in each coating portion 16. A cutting process for cutting along the short direction is performed. The roll press apparatus 40 includes a first press roller 41 that performs a first pressing step, and a second press roller 45 that performs a second pressing step and a cutting step.

  The first press roller 41 is a columnar body, and includes a pair of first pressing rollers 42 having the rotation direction in the short direction of the electrode material 18 with the electrode material 18 interposed therebetween. Each of the first pressing rollers 42 includes a cylindrical main body member 43 as a shaft portion, and a first protruding portion 42a and a second protruding portion 42c as first pressing portions having a shape protruding from the outer peripheral surface of the main body member 43. Is provided. The first projecting portion 42 a is disposed opposite to a portion that becomes the first edge portion 12 a of the active material layer 12 as an edge portion in the longitudinal direction of the electrode material 18 in the coating portion 16. That is, the first projecting portion 42 a is disposed at a position to press the portion that becomes the first edge portion 12 a of the active material layer 12.

  The first protruding portion 42 a has a shape protruding in the radial direction from the outer peripheral surface of the main body member 43. The second projecting portion 42 c is disposed so as to face a portion that becomes the second edge portion 12 b of the active material layer 12 as an edge portion in the longitudinal direction of the electrode material 18 in the coating portion 16. That is, the second projecting portion 42 c is disposed at a position for pressing the portion that becomes the second edge portion 12 b of the active material layer 12. The second projecting portion 42 c has a shape protruding in the radial direction from the outer peripheral surface of the main body member 43. The first projecting portion 42 a and the second projecting portion 42 c are larger in diameter than the main body member 43. The diameter here means a diameter centered on the rotation axis of the first pressing roller 42. Further, the diameters of the first projecting portion 42 a and the second projecting portion 42 c are constant in the axial direction of the main body member 43.

  The first projecting portion 42a and the second projecting portion 42c are provided on the outer peripheral surfaces of the projecting portions 42a and 42c on the first pressing surface 42b and the second pressing surface having a width along the short direction of the electrode material 18. 42d. The dimensions of the pressing surfaces 42b and 42d in the axial direction of the main body member 43 are constant. As for the 1st press roller 42, only each protrusion part 42a, 42c makes each press surface 42b the part used as the 1st edge part 12a and the 2nd edge part 12b of both the active material layers 12 in each coating part 16. , 42d to perform the first pressing step. The widths of the pressing surfaces 42b and 42d are not particularly limited, and the widths of the first pressing surface 42b and the second pressing surface 42d correspond to the widths of the first edge portion 12a and the second edge portion 12b, respectively. .

  The diameter of each protrusion 42a, 42c should just be larger than the diameter of the main body member 43 at least. Moreover, although it is preferable that the diameter of each protrusion part 42a, 42c is equal, you may differ.

Although there is no restriction | limiting in particular as a material of the 1st press roller 42, A metal, hard rubber, etc. are mentioned.
The second press roller 45 is a columnar body, and includes a pair of second pressing rollers 46 with the electrode material 18 interposed therebetween. Each of the second pressing rollers 46 includes a roller main body 47 having the same diameter as the rotation axis A in the short direction of the electrode material 18. The roller body 47 has a constant radial size with the rotation axis A as the axis. Each of the second pressing rollers 46 has a cam shape in a plan view of the electrode material 18 in the short direction, and a third protruding portion 47a as a second pressing portion having a shape protruding from the rotation axis A along the radial direction. Have In other words, the third projecting portion 47 a has a larger diameter than the roller body 47. The large diameter here means that the size in the radial direction with the rotation axis A as the axis is large. The third projecting portion 47 a includes a third pressing surface 47 b that presses a portion that becomes the third edge 12 c of the active material layer 12 in the coating portion 16. The third pressing surface 47 b extends in the entire length in the short direction of the electrode material 18. One second pressing roller 46 has a blade portion 48 that extends in the short direction of the electrode material 18 at a position of the maximum diameter in the third protruding portion 47a and protrudes from the third protruding portion 47a. The other second pressing roller 46 has a third projecting portion 47 a but does not have a blade portion 48.

  The electrode material 18 is conveyed in the conveyance direction shown in FIG. The pair of second pressing rollers 46 synchronizes the rotation period of the cam, and performs a second pressing step in which the electrode material 18 is simultaneously pressed by both the third pressing surfaces 47b between the pair of second pressing rollers 46, A cutting step of cutting the electrode material 18 in the short direction by the blade portion 48 is performed. The length of the second pressing roller 46 along the short direction is larger than the width of the electrode material 18.

Although there is no restriction | limiting in particular as a material of each 2nd press roller 46, A metal, hard rubber, etc. are mentioned.
Moreover, there is no restriction | limiting in particular as a material of the blade part 48, Ceramics, a metal, etc. are mentioned.

  The cam shape of the second pressing roller 46 is not particularly limited, and the distance from the rotation axis A of the root portion of the blade portion 48 in the third projecting portion 47a is larger than the distance from the rotation axis A of the other portion. As long as it protrudes like this. In other words, the blade part 48 should just be arrange | positioned in the position of the largest diameter in the 3rd protrusion part 47a.

  5 (a) to 5 (e) show a second pressing step in which each coating portion 16 is pressed by the second press roller 45, and a cutting in which the electrode material 18 is cut in the short direction in the course of the second pressing step. It is explanatory drawing (sectional drawing) explaining a process. As shown in FIG. 5A, when the blade portion 48 of one of the second pressing rollers 46 faces upward (in the opposite direction to the electrode material 18), the second pressing roller 46 is not in contact with the electrode material 18. It is in the state of. The other second pressing roller 46 is synchronized with the one second pressing roller 46 and the cam rotation cycle.

  When one of the second pressing rollers 46 rotates and the blade portion 48 moves toward the electrode material 18, as shown in FIG. 5B, the third pressing surfaces 47b of both the second pressing rollers 46 are applied to the respective coatings. The part which contacts the part 16 and becomes the third edge part 12c of the active material layer 12 in each coating part 16 is pressed from both sides of the electrode material 18.

  Next, as shown in FIG. 5 (c), the blade portion 48 of one second pressing roller 46 is pressed against one coating portion 16, and the electrode material 18 is formed on the active material layer 12 in the coating portion 16. It cut | disconnects along the part used as the 3rd edge 12c, and a cutting process is completed. At this time, since the second pressing roller 46 has a cam shape, the third edge of the active material layer 12 in each coating portion 16 from the state of FIG. 5B to the state of FIG. The portion to be the portion 12c is gradually and strongly pressed from both sides of the electrode material 18 by both third pressing surfaces 47b. At this stage, the second pressing process is completed.

  When the cutting process is completed as shown in FIG. 5D, the separated electrode material 18 is pushed out by the rotation of the second pressing roller 46 and conveyed. Further, since the second pressing roller 46 has a cam shape, the active material layer 12 in each coating unit 16 to be conveyed next from the state of FIG. 5C to the state of FIG. The portion that becomes the third edge portion 12c is pressed from both sides of the electrode material 18 by both the third pressing surfaces 47b, and the force that is gradually pressed as the second pressing roller 46 rotates is weakened. Therefore, the part used as the 3rd edge part 12c of each active material layer 12 has a taper-shaped cross section in which a film thickness becomes small toward a cut part.

  In the second pressing step and the cutting step, the electrode material 18 is conveyed in the conveying direction without stopping, and the next second pressing step and cutting step are performed again as shown in FIG. In this manner, pressing of the portion that becomes the third edge 12c of the active material layer 12 in each coating portion 16 and cutting of the electrode material 18 are continuously performed.

According to the embodiment described in detail above, the following excellent effects are obtained.
(1) The pair of first pressing rollers 42 serves as a first pressing portion having a first pressing surface 42b at a position facing the portion that becomes the first edge 12a of the active material layer 12 in the coating portion 16. The 1st protrusion part 42a is provided. Furthermore, each 1st press roller 42 is the 2nd as a 1st press part which has the 2nd press surface 42d in the position facing the part used as the 2nd edge 12b of the active material layer 12 in the coating part 16. FIG. A protruding portion 42c is provided.

  Each first pressing roller 42 can press a portion that becomes the first edge 12a of the active material layer 12 in each coating portion 16 by the first protruding portion 42a and the first pressing surface 42b, and each second protruding roller 42 The portion 42c and the second pressing surface 42d can press the portion that becomes the second edge 12b of the active material layer 12 in each coating portion 16, and the other portions are not pressed. As a result, the first edge portion 12a and the second edge portion 12b of each active material layer 12 have higher adhesion to the metal foil 11 than before pressing. Therefore, when the plurality of obtained electrodes 10 are stacked, even if each of the edges 12a and 12b comes into contact with a positioning jig or the like when the electrode 10 is dropped or is positioned, each edge 12a, Generation | occurrence | production of the defect | deletion, such as fall of the active material particle from 12b (powder fall) and peeling of the active material from the metal foil 11, can be suppressed, and the battery performance of the electrode 10 obtained can be suppressed.

  Moreover, since the 1st press roller 42 is pressing only the 1st edge 12a and the 2nd edge 12b of the active material layer 12 in the coating part 16, when pressing the whole coating part 16 In comparison with this, the generation of wrinkles of the electrode material 18 at the time of pressing can be suppressed.

  (2) The pair of second pressing rollers 46 of the second press roller 45 has a cam shape and has a third protruding portion 47a as a second pressing portion. One second pressing roller 46 includes a third pressing surface 47 b and a blade 48 on the third projecting portion 47 a. The pair of second pressing rollers 46 are synchronized in cam rotation cycle. Therefore, each time the second pressing roller 46 makes one rotation, it is possible to press the portion that becomes the third edge portion 12 c in each coating portion 16 and to cut the electrode material 18. As a result, the third edge 12c of each active material layer 12 has improved adhesion to the metal foil 11, and when the obtained plurality of electrodes 10 are laminated, the active material from the third edge 12c is obtained. Generation | occurrence | production of the defect | deletion, such as particle fall (powder fall) and peeling of the active material from the metal foil 11, can be suppressed. Furthermore, since the 2nd press roller 46 cuts, conveying the electrode material 18, productivity of the electrode 10 can be improved compared with the case where conveyance is stopped and moved at every cutting.

  Further, since the second pressing roller 46 presses only the portion that becomes the third edge portion 12c of the active material layer 12 in each coating portion 16, compared to when the entire coating portion 16 is pressed, Generation | occurrence | production of the wrinkle of the electrode material 18 can be suppressed.

  (3) The manufacturing method of the electrode 10 becomes the part used as the 1st edge 12a of the active material layer 12 in each coating part 16, the part used as the 2nd edge 12b, and the 3rd edge 12c. A pressing step of pressing the part. By the pressing step, the first to third edge portions 12a to 12c of each active material layer 12 have higher adhesion to the metal foil 11 than before the pressing step. For this reason, when laminating the obtained plurality of electrodes 10, even when each of the edges 12 a to 12 c comes into contact with a positioning jig or the like when the electrode 10 falls or during positioning, each edge 12 a ˜12c deficiency can be suppressed. Moreover, in the pressing process, in each coating part 16, since only the part used as the 1st-3rd edge parts 12a-12c of the active material layer 12 is pressed, when pressing the whole coating part 16 In comparison, the generation of wrinkles in the electrode material 18 can be suppressed.

  Moreover, the manufacturing method of the electrode 10 includes a cutting step, and in the cutting step, the third edge 12c can be pressed and cut while the electrode material 18 is conveyed. For this reason, productivity can be improved compared with the case where conveyance is stopped and moved each time cutting is performed.

  (4) The cutting step of cutting the electrode material 18 cuts the electrode material 18 in the short direction while pressing the portion that becomes the third edge 12c of the coating portion 16 in the process of the second pressing step. . For this reason, the electrode material 18 can be cut into pieces.

  (5) The active material layer 12 of the electrode 10 has first to third edge portions 12a to 12c having a smaller film thickness than portions other than the first to third edge portions 12a to 12c as general portions. Furthermore, the third edge portion 12 c has a tapered shape in which the film thickness decreases toward the end portion in the longitudinal direction of the metal foil 11. For this reason, when the electrode 10 is laminated | stacked through a separator compared with the electrode with a constant film thickness of the active material layer 12, a separator and the 1st-3rd edge parts 12a-12c of the active material layer 12 A space is created between them, and a contact area between the electrolytic solution and the active material layer 12 is increased, so that the active material layer 12 is easily impregnated with the electrolytic solution. In addition, since the above space becomes a passage for gas generated during overcharge, gas escape is improved.

In addition, you may change the said embodiment as follows.
In the embodiment, the electrode 10 includes an uncoated portion 13 and a current collecting tab 14 having a shape protruding from a part of the uncoated portion 13, but the first edge 12a of the active material layer 12 You may have the structure where only the uncoated part 13 protruded from the part.

  In the embodiment, the first pressing roller 42 is provided with the first projecting portion 42a and the second projecting portion 42c, but the number of the projecting portions is appropriately changed according to the shape of the electrode material 18. Also good. For example, the exposed portion 17 of the electrode material 18 is provided at the long edge portions on both sides along the longitudinal direction of the electrode material 18 and the central portion in the short direction, and the two electrodes 10 are disposed in the short direction of the electrode material 18. When forming, four protrusion parts are provided corresponding to the first edge part 12a and the second edge part 12b of the active material layer 12.

  In the embodiment, the first pressing roller 42 includes the first protruding portion 42a and the second protruding portion 42c. However, the first pressing roller 42 is divided into two in the axial direction, and one of the first pressing rollers 42 It is good also as a structure provided with the 1st protrusion part 42a and the other 1st press roller provided with the 2nd protrusion part 42c.

  In the embodiment, the first press roller 41 includes the first pressing roller 42 at one place in the carrying direction, but the first pressing roller 42 is provided at two places in the carrying direction, and the carrying direction of the electrode material 18 It is good also as a structure arrange | positioned continuously, and one 1st press roller is provided with the 1st protrusion part 42a, and the other 1st press roller is provided with the 2nd protrusion part 42c.

  In the embodiment, the diameters of the first projecting portion 42a and the second projecting portion 42c are constant in the axial direction of the main body member 43, but each projecting portion 42a, The diameter of 42c may gradually increase. Specifically, the diameter of the first projecting portion 42 a gradually increases toward the end portion of the electrode material 18 on the exposed portion 17 side in the main body member 43. The diameter of the second projecting portion 42 c gradually increases toward the end of the main body member 43 that is opposite to the exposed portion 17 of the electrode material 18. At this time, each pressing surface 42b, 42d has a tapered surface. In this case, when the portions that become the first edge portion 12a and the second edge portion 12b of the active material layer 12 in the coating portion 16 are pressed, the portion that becomes the first edge portion 12a faces the exposed portion 17. The portion that becomes the second edge portion 12b has a tapered shape with a small film thickness toward the end portion on the side opposite to the exposed portion 17. In other words, the first edge portion 12a of the active material layer 12 of the electrode 10 manufactured through the pressing by the first protruding portion 42a and the second protruding portion 42c is a film facing the uncoated portion 13. The second edge portion 12b has a tapered shape with a reduced thickness toward the end in the short direction of the metal foil 11. Therefore, all of the first to third edges 12a to 12c of the active material layer 12 of the electrode 10 have a tapered shape. As a result, the portion that becomes the first edge portion 12a can be gradually pressed strongly toward the exposed portion 17, and the portion that becomes the second edge portion 12b moves toward the end portion on the side opposite to the exposed portion 17. It can be pressed gradually and gradually. Therefore, the generation of wrinkles of the electrode material 18 at the time of pressing can be suppressed more than when the portions that become the first and second edge portions 12a and 12b of the active material layer 12 are pressed with the same force.

  In the embodiment, the second pressing roller 46 includes the blade portion 48 having a shape extending linearly over the entire short direction of the electrode material 18, but is formed in a spiral shape in the short direction of the electrode material 18. A blade portion 48 may be provided.

In the embodiment, the pair of second pressing rollers 46 has a cam shape, but one second pressing roller 46 may have a columnar shape instead of a cam shape.
As shown in FIG. 7, the second pressing roller of the second press roller 45 of the embodiment surrounds the tooth portion 52 as a protruding portion having a shape protruding from the outer peripheral surface of the roller body 51 as the same diameter portion. It may be a gear-shaped pressing cutter 50 having a plurality in the direction. In other words, the second pressing roller may be a gear-shaped pressing cutter 50 having a plurality of tooth portions 52 as second pressing portions having a larger diameter than the roller body 51.

  The tooth portion 52 includes a third pressing surface 52 a that presses the third edge portion 12 c of the active material layer 12 in the coating portion 16. The tooth portion 52 includes a blade portion 53 having a shape extending in the short direction of the electrode material 18 and protruding in the radial direction on the third pressing surface 52a. The tooth part 52 has a size that is larger from the axis of the rotation shaft toward the blade part 53 and has a line-symmetric shape with respect to a straight line connecting the blade part 53 and the axis of the rotation axis. That is, the blade portion 53 is disposed at the center portion of the tooth portion 52, and the center portion of the tooth portion 52 is a position of the maximum diameter in the tooth portion 52.

  When comprised in this way, only the 3rd edge 12c of the coating part 16 can be pressed with the tooth | gear part 52. FIG. Therefore, even if the portion that becomes the third edge portion 12c increases the active material filling density by pressing, the gap reduction of the entire electrode 10 is suppressed, and the amount of the electrolyte solution impregnated inside the electrode 10 is maintained. An electrochemical reaction can be satisfactorily caused to ensure output of battery performance.

(Circle) before being laminated | stacked, the electrode 10 may be used by adsorption | suction, a holding | grip, etc.
The power storage device may be another power storage device such as an electric double layer capacitor.
In the embodiment, the secondary battery is a lithium ion secondary battery, but is not limited to this, and may be another secondary battery such as nickel metal hydride.

  DESCRIPTION OF SYMBOLS 10 ... Electrode, 11 ... Metal foil as a collector, 12 ... Active material layer, 12a ... 1st edge part, 12b ... 2nd edge part, 12c ... 3rd edge part, 13 ... Uncoated part , 15 ... strip-shaped current collector, 16 ... coating section, 18 ... electrode material as strip-shaped electrode, 20 ... manufacturing device, 30 ... transporting device, 41 ... first press roller, 42a ... first as first pressing portion 1 protrusion part, 42b ... 1st press surface, 42c ... 2nd protrusion part as 1st press part, 42d ... 2nd press surface, 43 ... main body member as a shaft part, 45 ... 2nd press roller, 46 ... second pressing roller, 47 ... roller main body as the same diameter portion, 47a ... third projecting portion as the second pressing portion, 47b ... third pressing surface, 48, 53 ... blade portion.

Claims (9)

At least a plurality of electrodes used in a stacked manner, an active material mixture coated portion, and an uncoated portion where the active material mixture is not applied are arranged in the short direction of the belt-shaped current collector, and An apparatus for manufacturing an electrode for manufacturing by pressing and cutting the coating portion in the electrode material formed continuously in the longitudinal direction,
A transport device for transporting the strip current collector in the longitudinal direction of the strip current collector;
A press roller installed in a transport path of the strip current collector by the transport device and extending in a short direction of the strip current collector;
The press roller has a projecting portion having a pressing surface that presses an edge of a region to be a coating portion of the active material mixture in the electrode;
A blade portion protruding from the pressing surface and extending over the entire short-side direction of the strip-shaped current collector;
An apparatus for manufacturing an electrode, comprising:   2. The electrode manufacturing apparatus according to claim 1, wherein the protruding portion presses at least an edge portion of the region to be the coating portion, excluding an edge portion on the uncoated portion side. The press roller is a first press roller that presses at least the opposite edge among the edge on the uncoated part side and the opposite edge of the edge in the area to be the coated part. When,
A second press roller that presses the edge of the region to be the coated portion, excluding the edge on the uncoated portion side and the edge on the opposite side;
An apparatus for manufacturing an electrode according to claim 1, comprising: The second press roller has a cam shape,
The electrode manufacturing apparatus according to claim 3, comprising the same-diameter portion and the projecting portion having a diameter larger than that of the same-diameter portion, and having the blade portion at a maximum diameter position in the projecting portion. The second press roller has a gear shape having a plurality of protruding portions in the circumferential direction,
The electrode manufacturing apparatus according to claim 3, wherein the blade portion is provided at a central portion of the protruding portion. At least a plurality of electrodes used by laminating, the coated portion of the active material mixture, and the uncoated portion where the active material mixture is not applied are aligned in the short direction of the belt-like current collector, and the longitudinal direction A method for producing an electrode for producing by pressing and cutting the coated portion in an electrode material formed continuously in a direction,
While transporting the strip-shaped current collector in the longitudinal direction of the strip-shaped current collector, at least the edge portion on the uncoated portion side of the region that becomes the coated portion of the electrode in the strip-shaped current collector. A pressing step for pressing the removed edge;
In the course of the pressing step, a cutting step of cutting the electrode material along the short direction of the strip current collector;
The manufacturing method of the electrode containing this. The pressing step includes a first pressing step of pressing at least the edge portion that is the opposite side of the edge portion on the uncoated portion side in the region that is the coating portion and the edge portion that is the opposite side of the edge portion; ,
After the first pressing step, in the region to be the coating portion, including a second pressing step for pressing the edge portion excluding the edge portion on the uncoated portion side and the edge portion on the opposite side,
The method for manufacturing an electrode according to claim 6, wherein the cutting step is performed in the course of the second pressing step. A transport device for transporting a strip electrode having a coating portion in which an active material mixture is applied to the surface of the strip collector in the longitudinal direction of the strip electrode;
A first press roller that is a columnar body having a short axis direction of the belt-like electrode as a rotation axis, and presses the longitudinal direction of the belt-like electrode;
A columnar body having a short axis direction of the belt-like electrode as a rotation axis, and a second press roller that presses the short side direction of the belt-like electrode, and an electrode manufacturing apparatus comprising:
The first press roller has a shaft portion, and a first pressing portion having a larger diameter than the shaft portion,
The first pressing part is arranged at a position to press the longitudinal edge of the coating part,
The second press roller has the same diameter portion, and a second pressing portion having a larger diameter than the same diameter portion,
The said 2nd press part is an electrode manufacturing apparatus which has the blade part extended in the said transversal direction in the position of the largest diameter. A rectangular active material layer coated with an active material mixture on at least one surface of the current collector, and an uncoated portion where the surface of the current collector is exposed,
The active material layer has a general part and an edge part,
The edge is at least partially adjacent to the uncoated part, a first edge, a second edge located opposite to the first edge, the first edge, and the first edge. A pair of third edges connecting the two edges,
At least the second edge part and the third edge part have a thickness of the active material layer smaller than that of the general part,
The electrode of the power storage device, wherein the third edge portion has a tapered shape with a small thickness toward an end portion of the current collector.