Winding device

Abstract

To provide a winding device that can more reliably prevent collision of tabs with an outer peripheral surface of a transfer roller, and can effectively prevent breaking of the tabs.SOLUTION: A winding device comprises a rotatable winding core, and electrode sheets 4, 5 having tabs 4b, 5b are supplied to the winding core while being accelerated or decelerated. The winding device includes a rotatable transfer roller 711, an outer peripheral surface of which is covered by the electrode sheets 4, 5, and an upstream blow device 715 that can blow air. The upstream blow device 715 is provided at an immediately upstream position of the transfer roller 711 along a conveyance direction of the electrode sheets 4, 5, and can blow air directed from the root toward the leading end of the tabs 4b, 5b, simultaneously to both the front side and the rear side of the tabs 4b, 5b. The air blown from the upstream blow device 715 prevents the shaking motion of the tabs 4b, 5b and prevents collision of the tabs 4b, 5b with the transfer roller 711.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a winding device for obtaining a wound element to be built into, for example, a secondary battery or the like. [Background technology]

[0002] For example, a wound element used in a secondary battery such as a lithium ion battery is produced by winding a positive electrode sheet coated with a positive electrode active material and a negative electrode sheet coated with a negative electrode active material in a superimposed state with a separator sheet made of an insulating material interposed therebetween.

[0003] A known electrode sheet has an electrode body having an active material on its surface and tabs protruding from the widthwise edge of the electrode body. The tabs are provided at intervals along the longitudinal direction of the electrode body.

[0004] A winding device for manufacturing a wound element is known that includes a rotatable core and a supply mechanism for supplying an electrode sheet and a separator sheet to the core. Such a winding device is provided with a freely rotatable transport roller on which the electrode sheet or the like is hung, and the transport roller has a role of determining a transport path for the electrode sheet or the like.

[0005] However, when an electrode sheet having a tab passes through a transfer roller, the tab may bend. To deal with such tab bending, a technique has been proposed in which a deformation prevention member is provided at a position on the transfer roller that corresponds to the entrance of the electrode sheet (see, for example, Patent Document 1, etc.). The deformation prevention member is provided apart from the outer peripheral surface of one end of the transfer roller in the width direction. The tab is guided between the deformation prevention member and the transfer roller, thereby preventing the tab from bending. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2016-35892 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, after extensive research, the inventors of the present invention have discovered the following factors that cause the tab to break.

[0008] That is, when the electrode sheet is wound, it is not always transported at a constant speed, but is transported while being accelerated and decelerated. Such acceleration and deceleration of the electrode sheet causes vibration and resonance in the electrode sheet, which in turn causes the tab to swing along the thickness direction of the electrode sheet. Then, when the swinging tab collides with the outer circumferential surface of the transport roller, the tab jumps up, and as a result, the tab breaks.

[0009] In this regard, the technology described in the above Patent Document 1 does nothing to solve the problem of the tab colliding with the outer circumferential surface of the transfer roller and being thrown up. On the contrary, the thrown up tab may collide with the deformation prevention member, causing deformation or damage to the tab.

[0010] The present invention has been made in consideration of the above circumstances, and its object is to provide a winding device that can more reliably prevent the tab from colliding with the outer peripheral surface of the transfer roller and effectively prevent the tab from breaking. [Means for solving the problem]

[0011] The following describes each of the means suitable for achieving the above object. Note that, as necessary, the specific effects of the corresponding means will be added.

[0012] Means 1. Equipped with a rotatable core, A winding device that supplies a strip-shaped electrode sheet having an electrode main body having an active material on a surface thereof and a plurality of tabs protruding from widthwise edges of the electrode main body and provided at intervals along a longitudinal direction of the electrode main body, and a strip-shaped separator sheet made of an insulating material to the winding core while rotating the winding core, the winding core overlapping and winding the electrode sheet and the separator sheet, The electrode sheet is configured to be supplied to the winding core while being accelerated or decelerated, a rotatable transfer roller having an outer circumferential surface on which the electrode sheet is hung and defining a transfer path for the electrode sheet; a blowing means provided immediately upstream of the transfer roller in the transport direction of the electrode sheet, and capable of blowing gas from the base side to the tip side of the tab simultaneously onto both the front side and the back side of the tab.

[0013] According to the above-mentioned means 1, the electrode sheet is supplied to the core while being accelerated and decelerated. Therefore, the tab vibrates due to vibration or resonance caused by the acceleration or deceleration of the electrode sheet, and as a result, the tab may collide with the outer circumferential surface of the transfer roller, causing the tab to break.

[0014] In this regard, according to the above-mentioned means 1, the blowing means can blow gas from the base side of the tab to the tip side thereof simultaneously on both the front side and the back side of the tab. Therefore, even if the tab vibrates, the vibration can be suppressed and the tab can be returned to a normal state. This can more reliably prevent the tab from colliding with the outer circumferential surface of the transfer roller, and thus can suppress the tab from jumping up due to the collision with the outer circumferential surface of the transfer roller. As a result, the tab can be effectively prevented from being broken.

[0015] In addition, since the collision of the tab with the outer circumferential surface of the transport roller is prevented, the tab can be kept in good condition with less damage, and the quality of the wound element obtained can be improved.

[0016] Means 2. The tab is provided on one end side in the width direction of the electrode sheet, the electrode sheet has a coated portion provided on the other end side of the electrode sheet in the width direction relative to the tab and coated with an active material, The winding device according to Means 1, characterized in that the gas outlet of the blowing means is located closer to one end of the electrode sheet in the width direction than the coating section.

[0017] According to the above-mentioned means 2, the gas outlet of the blowing means is located closer to one end of the width direction of the electrode sheet than the coated portion. In other words, when the electrode sheet is viewed in plan, the gas outlet is provided at a position on the tab side, away from the coated portion. This makes it possible to more reliably prevent the scattering of dust adhering to the coated portion due to the gas hitting the coated portion. As a result, it is possible to more effectively improve the quality of the obtained wound element.

[0018] Means 3. The winding device described in Means 1, characterized in that it is provided with a straightening plate provided at a position adjacent to the tip of the tab that is the target of the gas blown from the blowing means, along the flow direction of the gas blown from the blowing means.

[0019] At the tip of the tab, turbulence may occur due to the interaction between the gas blown to the front side of the tab and the gas blown to the back side of the tab, which may have a detrimental effect on suppressing the vibration of the tab.

[0020] In this regard, according to the above-mentioned Means 3, the occurrence of the above-mentioned turbulent flow can be more reliably prevented by the straightening plate, and therefore the vibration of the tab can be more reliably suppressed, and thus the effect of preventing the tab from being broken can be further improved.

[0021] Means 4. A winding device as described in Means 1, characterized in that it has a suction port provided at a position adjacent to the tip of the tab that is the target of the gas blown from the blowing means, along the flow direction of the gas blown from the blowing means, and is equipped with suction means capable of sucking in gas through the suction port.

[0022] According to the above-mentioned means 4, the occurrence of the above-mentioned turbulence can be more reliably prevented by sucking the gas with the suction means, and as a result, the effect of preventing the tab from breaking can be further improved. In addition, the suction means can suck up dust, so that the quality of the obtained wound element can be more effectively improved.

[0023] Means 5. A winding device as described in Means 1, further comprising a roller outer periphery blowing means provided in correspondence with the tab at the portion of the electrode sheet that is hung on the transfer roller, and capable of applying a force to the tab toward the rotation axis of the transfer roller by blowing gas onto the tab.

[0024] The portion of the electrode sheet that is hung on the transport roller is deformed into a curved shape, and this deformation may cause the tabs to rise up. Such tab rise may lead to damage to the tabs due to contact with peripheral devices or poor welding when welding multiple tabs together, which may result in a decrease in product quality (quality of the wound element) and productivity.

[0025] In this regard, according to the above-mentioned means 5, the rising of the tab as described above can be prevented more reliably by the gas blown toward the tab from the roller outer periphery side blowing means, and therefore, it is possible to improve the product quality and productivity.

[0026] Means 6. The winding device described in Means 1, characterized in that the electrode sheet transported in a horizontal or obliquely horizontal direction is hung on the transport roller at a position immediately upstream of the transport roller in the transport direction of the electrode sheet.

[0027] According to the above-mentioned means 6, the electrode sheet is transported in a horizontal direction or an obliquely horizontal direction at the position immediately upstream of the transport roller. Therefore, the tab of the electrode sheet is likely to droop at the position immediately upstream of the transport roller, and as a result, the tab may be more likely to sag. If the tab is more likely to sway, it is more likely to collide with the outer circumferential surface of the transport roller.

[0028] In this regard, by employing the above-mentioned means 1, it is possible to more reliably suppress the vibration of the tab, and thus to extremely effectively prevent the tab from breaking, even under conditions in which the vibration of the tab is likely to occur, as in the above-mentioned means 6. In other words, it can be said that the above-mentioned means 1 functions particularly effectively when the electrode sheet transported in the horizontal or obliquely horizontal direction is hung on the transport roller at a position immediately upstream of the transport roller.

[0029] In addition, the technical matters related to the above-mentioned means may be combined as appropriate. For example, the technical matters related to the above-mentioned means 2 may be combined with the technical matters related to the above-mentioned means 5. [Brief description of the drawings]

[0030] [Figure 1] FIG. 2 is a perspective view showing a schematic configuration of a battery element. [Diagram 2] FIG. 2 is a plan view showing a schematic configuration of a positive electrode sheet. [Diagram 3] FIG. 2 is a plan view showing a schematic configuration of a negative electrode sheet. [Figure 4] FIG. 2 is a schematic diagram of a winding device. [Diagram 5] FIG. 2 is a schematic configuration diagram of a winding section. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] FIG. 7 is a partially enlarged cross-sectional view taken along line JJ in FIG. [Figure 9] FIG. 7 is a partially enlarged cross-sectional view taken along line KK in FIG. 6. [Figure 10] FIG. [Figure 11] FIG. 13 is a schematic configuration diagram of a winding section when a separator sheet is disposed in a gap in a winding core. [Figure 12] FIG. 13 is a schematic diagram of a winding section when cutting a separator sheet. [Figure 13] 1 is a schematic diagram of a winding section when winding of an electrode sheet or the like is completed; FIG. [Figure 14] FIG. 11 is a partially enlarged cross-sectional view showing an upstream blow nozzle and the like provided in an inclined state in another embodiment. [Figure 15] FIG. 13 is a schematic perspective view showing an upstream blow device and the like in another embodiment. [Figure 16] FIG. 11 is a schematic side view showing a plurality of pairs of upstream blow nozzles and the like in another embodiment. [Figure 17] FIG. 13 is a schematic perspective view showing a shielding plate and the like in another embodiment. [Figure 18] 13 is a schematic side view showing a shielding plate and the like in another embodiment. FIG. [Figure 19] FIG. 13 is a schematic perspective view showing a current plate and the like in another embodiment. [Figure 20] 20 is a partially enlarged cross-sectional view taken along line JJ in FIG. 19. [Figure 21] FIG. 13 is a schematic perspective view showing a suction device and the like in another embodiment. [Figure 22] 22 is a partially enlarged cross-sectional view taken along line JJ in FIG. 21. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] An embodiment will be described below with reference to the drawings. First, the configuration of a lithium ion battery element as a wound element obtained by a winding device will be described.

[0032] As shown in FIG. 1, a lithium ion battery element 1 (hereinafter simply referred to as "battery element 1") is manufactured by winding a positive electrode sheet 4 and a negative electrode sheet 5 in a superimposed state with two separator sheets 2 and 3 interposed therebetween. In this embodiment, the positive electrode sheet 4 and the negative electrode sheet 5 each correspond to an "electrode sheet". Note that instead of the two separator sheets 2 and 3, a single folded separator sheet may be used. In the following, for convenience of explanation, the separator sheets 2 and 3 and the electrode sheets 4 and 5 may be referred to as "various sheets 2 to 5".

[0033] The separator sheets 2, 3 are each in the form of a strip having the same width, and are made of an insulator such as polypropylene (PP) to prevent the different electrode sheets 4, 5 from coming into contact with each other and causing a short circuit.

[0034] Each of the electrode sheets 4, 5 is made of a thin metal sheet, and for example, an aluminum foil sheet is used for the positive electrode sheet 4, and for example, a copper foil sheet is used for the negative electrode sheet 5. Each of the electrode sheets 4, 5 is relatively thin (for example, 5 to 50 μm or 10 to 30 μm thick).

[0035] 2 and 3, each of the electrode sheets 4 and 5 includes an electrode main body 4a, 5a and a tab 4b, 5b. In this embodiment, the side of the electrode main body 4a on which the tab 4b is provided is referred to as one widthwise end side of the electrode main body 4a, and the side of the electrode main body 5a on which the tab 5b is provided is referred to as one widthwise end side of the electrode main body 5a.

[0036] The electrode main bodies 4a, 5a have approximately the same width as the separator sheets 2, 3, and an active material is applied to both the front and back surfaces of the electrode main bodies 4a, 5a. The electrode main body 4a of the positive electrode sheet 4 is applied with a positive electrode active material (e.g., lithium manganate particles, etc.) (in Figures 2, 3, etc., the applied portion of the active material is shown in a scattered dot pattern). That is, the front and back surfaces of the positive electrode sheet 4 are provided with positive electrode coated parts 4c coated with the positive electrode active material. The positive electrode coated parts 4c are located on the other end side of the positive electrode sheet 4 in the width direction relative to the tab 4b.

[0037] On the other hand, a negative electrode active material (e.g., activated carbon) is applied to the electrode main body 5a of the negative electrode sheet 5. That is, a negative electrode coated portion 5c formed by applying a negative electrode active material is provided on the front and back surfaces of the negative electrode sheet 5. The negative electrode coated portion 5c is located closer to the other end in the width direction of the negative electrode sheet 5 than the tab 5b. In this embodiment, the positive electrode coated portion 4c and the negative electrode coated portion 5c each correspond to a "coated portion".

[0038] Ion exchange is then possible between the positive electrode sheet 4 and the negative electrode sheet 5 via the active material. Although Figures 2 and 3 show a configuration in which the active material is not applied to a portion (e.g., the widthwise edge portion) of the electrode main body 4a, 5a, the active material may be applied to the entire area of ​​the electrode main body 4a, 5a. In other words, the coated portion 4c, 5c may be provided over the entire area of ​​the electrode main body 4a, 5a.

[0039] The tabs 4b, 5b are so-called molded tabs formed by cutting out a part of the electrode material, and are integrated with the electrode main body parts 4a, 5a. The tabs 4b, 5b protrude from one end edge in the width direction of the electrode main body parts 4a, 5a, and are provided at intervals along the longitudinal direction of the electrode main body parts 4a, 5a. In this embodiment, the tab 4b of the positive electrode sheet 4 is located at one end side of the battery element 1 along the central axis CL direction of the battery element 1, and the tab 5b of the negative electrode sheet 5 is located at the other end side of the battery element 1 along the central axis CL direction (see FIG. 1). That is, the two tabs 4b, 5b are located at different ends of the battery element 1. The two tabs 4b, 5b may be located at the same end side of the battery element 1.

[0040] When obtaining a lithium ion battery, the battery element 1 is disposed in a cylindrical metallic battery container (case) (not shown), and the tabs 4b and 5b are bundled together. If necessary, the bundled tabs 4b and 5b are welded together. The bundled tabs 4b are then connected to a positive electrode terminal part (not shown), and the bundled tabs 5b are connected to a negative electrode terminal part (not shown), and the two terminal parts are provided to close both end openings of the battery container, thereby obtaining a lithium ion battery.

[0041] Next, a winding device 10 for manufacturing the battery element 1 will be described. As shown in Fig. 4, the winding device 10 includes a winding section 11 for winding the various sheets 2 to 5, a positive electrode sheet supply mechanism 31 for supplying the positive electrode sheet 4 to the winding section 11, a negative electrode sheet supply mechanism 41 for supplying the negative electrode sheet 5 to the winding section 11, separator supply mechanisms 51 and 61 for supplying the separator sheets 2 and 3 to the winding section 11, respectively, and a control device 91. The operation of various mechanisms in the winding device 10, such as the winding section 11 and the supply mechanisms 31, 41, 51, and 61, is controlled by the control device 91.

[0042] The positive electrode sheet supply mechanism 31 includes a positive electrode sheet original 32 in which the positive electrode sheet 4 is wound in a roll shape. The positive electrode sheet original 32 is supported so as to be freely rotatable, and the positive electrode sheet 4 is appropriately pulled out from there.

[0043] The positive electrode sheet supply mechanism 31 includes a roller device 71, a positional relationship maintaining mechanism 72, a sheet inserting mechanism 73, a sheet cutting cutter 74, a tension applying mechanism 75, and a buffer mechanism .

[0044] The roller device 71 is a device having the positive electrode sheet 4 hung on its outer circumferential surface and including a transfer roller 711 for determining a transport path for the positive electrode sheet 4. A plurality of roller devices 71 (transfer rollers 711) are provided along the transport path for the positive electrode sheet 4. The configuration of the roller device 71 will be described in detail later.

[0045] The positional relationship maintaining mechanism 72 is provided at a position immediately upstream of the transfer roller 711 along the transport path of the positive electrode sheet 4, and serves to maintain an appropriate positional relationship between an upstream blow device 715 (described later) of the roller device 71 and the positive electrode sheet 4 hung on the transfer roller 711. The configuration of the positional relationship maintaining mechanism 72 will also be described later.

[0046] The sheet insertion mechanism 73 is for supplying the positive electrode sheet 4 to the winding unit 11 while holding it.

[0047] The sheet cutting cutter 74 is for cutting the positive electrode sheet 4. The cutting of the positive electrode sheet 4 is performed in a state in which the positive electrode sheet 4 is gripped by the sheet insertion mechanism 73. In addition, the sheet cutting cutter 74 can be separated from the conveyance path of the positive electrode sheet 4 so as not to impede the supply of the positive electrode sheet 4 by the sheet insertion mechanism 73.

[0048] The tension applying mechanism 75 is for applying tension to the positive electrode sheet 4, and includes a plurality of rollers (e.g., dancer rollers, etc.). The operation of these rollers is controlled by the control device 91, so that the tension applied from the tension applying mechanism 75 to the positive electrode sheet 4 can be adjusted. In this embodiment, the tension applying mechanism 75 is configured to always apply a constant tension to the positive electrode sheet 4. The rollers constituting the tension applying mechanism 75 may have the same configuration as the transfer roller 711. Therefore, for example, an upstream blowing device 715 and a roller outer periphery side blowing device 716, which will be described later, may be applied to the rollers constituting the tension applying mechanism 75.

[0049] The buffer mechanism 76 has, for example, a pair of driven rollers and a lift roller disposed between the rollers so as to be displaceable in the up and down direction, and serves to temporarily store the positive electrode sheet 4. The rollers constituting the buffer mechanism 76 may have the same configuration as the transfer roller 711.

[0050] The negative electrode sheet supply mechanism 41 includes, at its most upstream side, a negative electrode sheet original 42 in which the negative electrode sheet 5 is wound in a roll shape. The negative electrode sheet original 42 is supported so as to be freely rotatable, and the negative electrode sheet 5 is appropriately pulled out from there.

[0051] Further, in the middle of the transport path of the negative electrode sheet 5 from the negative electrode sheet raw material 42 to the winding section 11, a roller device 71, a positional relationship maintaining mechanism 72, a sheet insertion mechanism 73, a sheet cutting cutter 74, a tension applying mechanism 75, a buffer mechanism 76, and the like are provided, similar to the transport path of the positive electrode sheet 4. These are similar to those provided in the transport path of the positive electrode sheet 4, except that they function for the negative electrode sheet 5.

[0052] On the other hand, the separator supply mechanisms 51, 61 are provided with separator original rolls 52, 62 each formed by winding up the separator sheets 2, 3 in a roll shape. The separator original rolls 52, 62 are supported so as to be freely rotatable, and the separator sheets 2, 3 are appropriately pulled out from them.

[0053] Furthermore, the separator supply mechanisms 51 and 61, like the electrode sheet supply mechanisms 31 and 41, are provided with a tension applying mechanism 75. This is similar to the one provided in the positive electrode sheet supply mechanism 31, except that it functions for the separator sheets 2 and 3.

[0054] Next, the configuration of the winding unit 11 will be described. As shown in Fig. 5, the winding unit 11 includes a turret 12 consisting of two opposing disk-shaped tables rotatably provided by a driving mechanism (not shown), two winding cores 13, 14 provided at 180° intervals in the rotation direction of the turret 12, two support rollers 15a, 15b provided at positions shifted by approximately 90° from the winding cores 13, 14 in the rotation direction of the turret 12, a separator cutter 16, a pressing roller 17 for pressing the various sheets 2 to 5 just before the winding is completed, and a tape application mechanism 18 for applying a predetermined fixing tape. In addition, the winding unit 11 includes a removal device (not shown) for removing the battery element 1 from the winding cores 13, 14 in the periphery of a removal position P2 described later.

[0055] The winding cores 13 and 14 are adapted to take up the various sheets 2 to 5 on their respective outer peripheries and are configured to be rotatable about their own central axes as the rotation axes by a drive mechanism (not shown). The amount of rotation of the winding cores 13 and 14 can be grasped by an encoder (not shown), and information relating to the amount of rotation is input from the encoder to the control device 91.

[0056] The winding cores 13 and 14 are provided so as to be able to protrude into and retract from one of the tables constituting the turret 12 along the axial direction of the turret 12 (the depth direction of the paper in FIG. 5). When the winding cores 13 and 14 protrude from one of the tables, their tips are inserted into receiving holes formed in the other table and are supported in a rotatable state by both tables.

[0057] In addition, the winding cores 13 and 14 are each configured to have a non-circular shape in a cross section perpendicular to the rotation axis. In this embodiment, the winding cores 13 and 14 have an elliptical shape in a cross section perpendicular to their own rotation axis. Since the winding cores 13 and 14 have a non-circular cross section, even when the winding cores 13 and 14 are rotated at a constant speed, the various sheets 2 to 5 are supplied to the winding cores 13 and 14 while accelerating and decelerating. Immediately after the start of winding the various sheets 2 to 5, the various sheets 2 to 5 are supplied to the winding cores 13 and 14 while accelerating, and immediately before the end of winding the various sheets 2 to 5, the various sheets 2 to 5 are supplied to the winding cores 13 and 14 while decelerating.

[0058] Furthermore, the winding core 13 (14) has a pair of core pieces 13a, 13b (14a, 14b) each extending along its own rotation axis direction (depth direction in the plane of the paper in FIG. 5). A gap 13c (14c) is formed between the core pieces 13a, 13b (14a, 14b). A chuck mechanism (not shown) is provided at a portion of the winding core 13 (14) that forms the gap 13c (14c) to clamp the separator sheets 2, 3 arranged in the gap 13c (14c).

[0059] Furthermore, the winding cores 13, 14 are configured to be rotatable between a winding position P1 and a removal position P2 by rotation of the turret 12. The winding position P1 is a position where the winding cores 13, 14 are positioned when winding the various sheets 2-5. The removal position P2 is a position where the winding cores 13, 14 are positioned when removing the various sheets 2-5 (i.e., the battery element 1) after winding.

[0060] The support rollers 15a, 15b are for hooking and supporting the various sheets 2 to 5 between the cores 13, 14 that have moved to the removal position P2 and the supply mechanisms 31, 41, 51, 61.

[0061] The separator cutter 16 is for cutting the separator sheets 2 and 3. The pressing roller 17 is for pressing the various sheets 2 to 5 that have been wound up.

[0062] The tape application mechanism 18 is for applying a fixing tape to the end portions of the separator sheets 2, 3 after the winding of the various sheets 2 to 5 is completed.

[0063] Next, the roller device 71 will be described. As shown in Fig. 6, the roller device 71 includes a transfer roller 711, a shaft portion 712, a bearing 713, a holder 714, an upstream blowing device 715, and a roller outer periphery blowing device 716. In this embodiment, the upstream blowing device 715 constitutes the "blowing means", and the roller outer periphery blowing device 716 constitutes the "roller outer periphery blowing means".

[0064] As described above, the electrode sheets 4, 5 are hung on the outer peripheral surface of the transfer roller 711, and the transfer roller 711 has a role of determining a transport path for the electrode sheets 4, 5. The transfer roller 711 is cylindrical and can freely rotate about a rotation axis RA. In this embodiment, the width of the transfer roller 711 is larger than the width of the electrode sheets 4, 5, so that the entire widthwise areas of the electrode sheets 4, 5, including the tabs 4b, 5b, are hung on the outer peripheral surface of the transfer roller 711.

[0065] In this embodiment, a plurality of roller devices 71 each having a transfer roller 711 are provided, and at least one of the transfer rollers 711 is adapted to receive the electrode sheets 4, 5 transferred horizontally or obliquely horizontally at a position immediately upstream of the transfer roller 711 along the transfer direction of the electrode sheets 4, 5. At the position immediately upstream of the transfer roller 711, the tabs 4b, 5b are likely to sag due to gravity.

[0066] The shaft portion 712 has a rod shape extending in the direction of the rotation axis RA, and both ends are supported by the holder 714. In this embodiment, the shaft portion 712 is fixed to the holder 714 and configured not to rotate around the rotation axis RA. Note that the shaft portion 712 may be configured to be rotatable relative to the holder 714 around the rotation axis RA.

[0067] The bearings 713 are provided between the shaft portion 712 and the transfer roller 711, and support the transfer roller 711 in a freely rotatable state relative to the shaft portion 712. The bearings 713 are attached, one on each end side of the transfer roller 711 in the direction of the rotation axis RA, with their central axes coinciding with the rotation axis RA (see FIG. 9).

[0068] The holder 714 supports both ends of the shaft portion 712, thereby supporting the transfer roller 711 via the shaft portion 712. In this embodiment, the holder 714 is fixed to a predetermined attachment portion W and is immovable.

[0069] The upstream blow device 715 is provided immediately upstream of the transfer roller 711 along the transport direction of the electrode sheets 4 and 5, and is a device for suppressing vibration of the tabs 4b and 5b. In this embodiment, the upstream blow device 715 constitutes the "blowing means."

[0070] The upstream blow device 715 includes a first blow device 7151 corresponding to the front side of the electrode sheets 4, 5 and a second blow device 7152 corresponding to the back side of the electrode sheets 4, 5 (see Figs. 7 and 8). In Fig. 8 and other figures, the tabs 4b, 5b may be given a lattice pattern, and the coated parts 4c, 5c may be indicated by thick lines. Each blow device 7151, 7152 includes a relatively thin cylindrical upstream blow nozzle 7151a, 7152a having an outlet 7151b, 7152b at the tip. Also, a gas (e.g., an inert gas) can be supplied from a predetermined air supply device (not shown) into each upstream blow nozzle 7151a, 7152a.

[0071] The two upstream blow nozzles 7151a, 7152a are provided symmetrically with respect to the electrode sheets 4, 5, and extend along the width direction of the electrode sheets 4, 5. The two upstream blow nozzles 7151a, 7152a are also arranged in parallel, and their blowing openings 7151b, 7152b are configured to be located closer to the other end of the electrode sheets 4, 5 in the width direction (opposite the tabs 4b, 5b) than the coating sections 4c, 5c.

[0072] Then, gas is simultaneously supplied from the air supply device into both upstream blow nozzles 7151a, 7152a, so that gas is blown from the outlets 7151b, 7152b from the base side (electrode main body part 4a, 5a side) of the tabs 4b, 5b toward the tip side thereof toward both the front and back sides of the tabs 4b, 5b. In this embodiment, the gas is configured so that the volume and speed of the gas blown from each outlet 7151b, 7152b are the same.

[0073] In this embodiment, gas is constantly supplied from the air supply device to the upstream blow nozzles 7151a and 7152a, and when the tabs 4b and 5b reach a predetermined position as the electrode sheets 4 and 5 are transported, gas is blown from the base side to the tip side of the tabs 4b and 5b. Note that the air supply device may be configured to supply gas to the upstream blow nozzles 7151a and 7152a every time the tabs 4b and 5b reach a predetermined position. In other words, the gas may be blown toward the tabs 4b and 5b only when the tabs 4b and 5b reach a predetermined position.

[0074] The roller outer periphery blowing device 716 is provided in correspondence with the tabs 4b, 5b of the electrode sheets 4, 5 that are hung on the transfer roller 711, and is a device for pressing the tabs 4b, 5b against the outer periphery of the transfer roller 711. In this embodiment, the roller outer periphery blowing device 716 constitutes the "roller outer periphery blowing means."

[0075] The roller outer periphery blow device 716 is provided with a plurality of outer periphery blow nozzles 7161 in an area HA (see FIG. 7) of the transfer roller 711 where the electrode sheets 4, 5 are hung. Each of these outer periphery blow nozzles 7161 has a relatively thin cylindrical shape, and a plurality of them (four at equal intervals in this embodiment) are provided at intervals along the circumferential direction of the transfer roller 711 on the outer periphery of the transfer roller 711. Also, a configuration is made such that gas can be supplied from the air supply device to the inside of each outer periphery blow nozzle 7161.

[0076] Furthermore, each outer circumferential blow nozzle 7161 is disposed at a slight incline with respect to the rotation axis RA, and the gas supply port 7161b located at the tip of the nozzle is configured to face the tabs 4b, 5b (see FIG. 9). Note that the gas supply port 7161b is configured to be located closer to the other end of the electrode sheets 4, 5 in the width direction than the coating sections 4c, 5c, similar to the blowing ports 7151b, 7152b.

[0077] Then, gas is supplied from the air supply device to each outer circumferential blow nozzle 7161, so that gas is blown from the gas supply port 7161b to the front side of the tabs 4b, 5b. This applies a force toward the rotation axis RA of the transfer roller 711 to the tabs 4b, 5b, so that the tabs 4b, 5b are pressed against the outer circumferential surface of the transfer roller 711. In this embodiment, the gas is configured so that the volume and speed of the gas blown from each gas supply port 7161b are the same.

[0078] In this embodiment, gas is constantly supplied from the air supply device to each outer periphery blow nozzle 7161, and when the tabs 4b, 5b reach a position on the front side of the gas supply port 7161b as the electrode sheets 4, 5 are transported, gas is blown toward the tabs 4b, 5b. Note that a configuration may be adopted in which gas is supplied from the air supply device into the outer periphery blow nozzle 7161 every time the tabs 4b, 5b reach a position on the front side of the gas supply port 7161b. In other words, a configuration may be adopted in which gas is blown toward the tabs 4b, 5b only when the tabs 4b, 5b reach a position on the front side of the gas supply port 7161b.

[0079] Next, the positional relationship maintaining mechanism 72 will be described. As described above, the positional relationship maintaining mechanism 72 is for maintaining an appropriate positional relationship between the upstream blow device 715 and the like and the electrode sheets 4, 5 hung on the transfer roller 711. In this embodiment, a positional relationship maintaining mechanism 72 corresponding to one of the multiple transfer rollers 711 in the positive electrode sheet supply mechanism 31 and a positional relationship maintaining mechanism 72 corresponding to one of the multiple transfer rollers 711 in the negative electrode sheet supply mechanism 41 are provided. Of course, a plurality of positional relationship maintaining mechanisms 72 may be provided along the transport path of each of the electrode sheets 4, 5. For example, a positional relationship maintaining mechanism 72 may be provided for each transfer roller 711.

[0080] 4, the positional relationship maintaining mechanism 72 includes a position detecting unit 721 that detects the widthwise position of the electrode sheets 4, 5, a correcting unit 722 that corrects the positional deviation of the electrode sheets 4, 5 in the widthwise direction based on the position detected by the position detecting unit 721, and a meandering correction actuator (not shown) for operating the correcting unit 722. The position detecting unit 721 is configured by, for example, an edge sensor capable of detecting the widthwise position of the electrode sheets 4, 5, and information relating to the widthwise position of the electrode sheets 4, 5 detected by the position detecting unit 721 is output to the control device 91.

[0081] As shown in FIG. 10, the correction unit 722 includes a pair of upper and lower rollers 722a, 722b, and is configured to be rotatable around a pivot center α at the upper center of the upper roller 722a by the correction actuator. The control device 91 controls the correction actuator, and the correction unit 722 rotates to correct the positional deviation of the electrode sheets 4, 5. This more reliably prevents the occurrence of variations in the relative positional relationship between the electrode sheets 4, 5 (particularly the tabs 4b, 5b) and the upstream blow device 715 (particularly the blowing ports 7151b, 7152b) and the roller outer periphery side blow device 716 (particularly the gas supply port 7161b). As a result, it becomes possible to more reliably blow gas in an appropriate state from the upstream blow device 715 and the roller outer periphery side blow device 716 toward the target position (the predetermined position of the tabs 4b, 5b).

[0082] In the winding device 10 configured as described above, the various sheets 2 to 5 are wound as follows. That is, with the separator sheets 2 and 3 stretched across the support rollers 15a (15b) and the like, one of the winding cores 13 (14) arranged at the winding position P1 is caused to protrude from one of the tables in the turret 12, so that the separator sheets 2 and 3 are arranged in the gap 13c (14c) of the winding core 13 (14) (see FIG. 11). Next, the separator sheets 2 and 3 arranged in the gap 13c (14c) are clamped by the chuck mechanism. Then, one of the winding cores 13 (14) is rotated a predetermined number of times, so that a predetermined amount of the separator sheets 2 and 3 is wound around the winding core 13 (14).

[0083] Next, the electrode sheets 4, 5 are sequentially supplied to one of the winding cores 13 (14) by the sheet insertion mechanism 73. Thereafter, the various sheets 2-5 are supplied to the winding core 13, 14 while the winding core 13 (14) is rotated, thereby overlapping and winding the various sheets 2-5. The winding of the various sheets 2-5 is performed while blowing gas from the upstream blowing device 715 and the roller outer periphery side blowing device 716.

[0084] Immediately after the start of winding the various sheets 2-5, the various sheets 2-5 are accelerated and supplied to the winding cores 13, 14. After a certain time has elapsed from the start of winding the various sheets 2-5, the winding cores 13, 14 rotate at a constant speed, and the various sheets 2-5 are accelerated and decelerated while being supplied to the winding cores 13, 14.

[0085] Thereafter, when a predetermined length of the various sheets 2 to 5 has been wound, the rotation of one of the winding cores 13 (14) is temporarily stopped. When the various sheets 2 to 5 are temporarily stopped, the various sheets 2 to 5 are fed to the winding cores 13, 14 while being decelerated. While the various sheets 2 to 5 are temporarily stopped, the electrode sheets 4, 5 are cut by the sheet cutting cutter 74.

[0086] Thereafter, the turret 12 rotates to remove one of the winding cores 13 (14) around which the various sheets 2 to 5 are wound, and moves it to position P2. This results in the separator sheets 2, 3 being suspended across the support rollers 15a (15b) and the like. The turret 12 also rotates to move the other winding core 14 (13) to winding position P1. The next winding of the various sheets 2 to 5 is performed on this winding core 14 (13).

[0087] Next, the pressure roller 17 is brought close to one of the winding cores 13 (14) arranged at the removal position P2, and the various sheets 2 to 5 are pressed by the pressure roller 17, and the separator sheets 2, 3 are cut by the separator cutter 16 (see FIG. 12). After that, the one of the winding cores 13 (14) is rotated to completely wind up the various sheets 2 to 5, and the fixing tape is applied to the end portions of the separator sheets 2, 3 by the tape application mechanism 18. This results in a battery element 1 that has been subjected to a winding stop process (see FIG. 13). The obtained battery element 1 is removed from the winding core 13 (14) by the removal device.

[0088] As described above in detail, according to this embodiment, the upstream blowing device 715 can blow gas from the base side of the tabs 4b, 5b toward the tip side thereof at both the front side and the back side of the tabs 4b, 5b at the same time. Therefore, as in this embodiment, since the electrode sheets 4, 5 are supplied to the winding cores 13, 14 while being accelerated and decelerated, even under conditions in which the tabs 4b, 5b are likely to vibrate, the vibrating motion of the tabs 4b, 5b that has occurred can be suppressed and the tabs 4b, 5b can be returned to a normal state. This makes it possible to more reliably prevent the tabs 4b, 5b from colliding with the outer circumferential surface of the transfer roller 711, and thus to suppress the tabs 4b, 5b from jumping up due to the collision with the outer circumferential surface of the transfer roller 711. As a result, the tabs 4b, 5b can be effectively prevented from being broken.

[0089] In addition, since the tabs 4b, 5b are prevented from colliding with the outer circumferential surface of the transfer roller 711, the tabs 4b, 5b are prevented from breaking, and the tabs 4b, 5b can be maintained in good condition with less damage. Therefore, the quality of the obtained battery element 1 can be improved.

[0090] In addition, the gas outlets 7151b, 7152b in the upstream blowing device 715 are located closer to one end of the width direction of the electrode sheets 4, 5 than the coated parts 4c, 5c. In other words, when the electrode sheets 4, 5 are viewed in plan, the gas outlets 7151b, 7152b are provided at positions on the tabs 4b, 5b side and away from the coated parts 4c, 5c. This makes it possible to more reliably prevent the scattering of dust adhering to the coated parts 4c, 5c due to the gas hitting the coated parts 4c, 5c. As a result, the quality of the obtained battery element 1 can be improved more effectively.

[0091] Furthermore, the portions of the electrode sheets 4, 5 hung on the transfer roller 711 are deformed into a curved shape, and while this deformation may cause the tabs 4b, 5b to rise, the rising of the tabs 4b, 5b can be more reliably prevented by the gas blown toward the tabs 4b, 5b from the roller outer periphery side blowing device 716. This makes it possible to more reliably prevent problems caused by the rising of the tabs 4b, 5b (for example, damage to the tabs 4b, 5b due to contact with peripheral devices, poor welding when welding multiple tabs 4b, 5b together, etc.), thereby improving the quality and productivity of the battery element 1.

[0092] In addition, in this embodiment, at least one of the transfer rollers 711 is adapted to receive the electrode sheets 4, 5 transported horizontally or obliquely horizontally. Therefore, at a position immediately upstream of the transfer roller 711, the tabs 4b, 5b are likely to sag due to gravity, and as a result, the tabs 4b, 5b may be likely to vibrate. However, by providing the upstream blow device 715, it is possible to more reliably prevent the tabs 4b, 5b from colliding with the transfer roller 711 even under conditions where the tabs 4b, 5b are likely to vibrate.

[0093] Furthermore, the positional relationship maintaining mechanism 72 (position detection unit 721 and correction unit 722) can maintain the positional relationship between the upstream blow device 715 and the roller outer periphery side blow device 716 and the positive electrode sheets 4, 5 hung on the transfer roller 711 in an appropriate state. Therefore, it becomes possible to more reliably blow gas from the upstream blow device 715 and the roller outer periphery side blow device 716 toward the target position (the predetermined position of the tabs 4b, 5b) in an appropriate state, and the vibration of the tabs 4b, 5b can be more reliably suppressed. As a result, the effect of preventing the tabs 4b, 5b from being broken can be further improved, and the condition of the tabs 4b, 5b can be improved.

[0094] The present invention is not limited to the above-described embodiment, and may be implemented as follows: Of course, other applications and modifications not exemplified below are also possible.

[0095] (a) In the above embodiment, both upstream blow nozzles 7151a, 7152a extend along the width direction of the electrode sheets 4, 5 and are configured to be parallel to the tabs 4b, 5b that do not vibrate. Alternatively, as shown in Fig. 14, both upstream blow nozzles 7151a, 7152a may be provided inclined with respect to the width direction of the electrode sheets 4, 5, and these blowing ports 7151b, 7152b may be configured to face the tabs 4b, 5b. Even in this configuration, the same effects as those of the above embodiment can be achieved.

[0096] (b) In the above embodiment, the upstream blow nozzles 7151a, 7152a and the outer periphery blow nozzle 7161 are each cylindrical, but the shapes of these blow nozzles 7151a, 7152a, 7161 may be changed as appropriate. Thus, for example, the upstream blow nozzles 7151a, 7152a may be rectangular tubular as shown in Fig. 15. Also, for example, the outer periphery blow nozzle 7161 may be curved so as to fit the outer periphery of the transfer roller 711.

[0097] (c) In the above embodiment, the upstream blow device 715 includes a pair of upstream blow nozzles 7151a, 7152a, but may include multiple pairs of upstream blow nozzles 7151a, 7152a as shown in Fig. 16. With this configuration, the effect of suppressing the swinging movement of the tabs 4b, 5b can be further improved.

[0098] (d) As shown in Figs. 17 and 18, a configuration may be adopted in which a shielding plate 717 is provided between the areas to which the gas is blown by the blow nozzles 7151a, 7152a, and 7161 adjacent to each other along the conveying direction of the electrode sheets 4 and 5. By providing the shielding plate 717, it is possible to more reliably prevent interference between the gases blown from the blow nozzles 7151a, 7152a, and 7161, and it is possible to further enhance the effect of suppressing the vibration of the tabs 4b and 5b. In the example shown in Figs. 17 and 18, the shielding plate 717 is provided corresponding to the area between the upstream blow nozzle 7151a and the outer circumferential blow nozzle 7161, but the shielding plate 717 may be provided corresponding to the area between multiple upstream blow nozzles 7151a or the area between multiple outer circumferential blow nozzles 7161. Of course, multiple shielding plates 717 may be provided.

[0099] 19 and 20, a flat rectifying plate 718 may be provided adjacent to the tip of the tab 4b, 5b, which is the target of the gas blown from the upstream blow device 715, along the flow direction of the gas blown from the upstream blow device 715, and arranged in a state parallel to the tab 4b, 5b. By providing the rectifying plate 718, it is possible to more reliably prevent the generation of turbulence caused by the interaction between the gas blown to the front side of the tab 4b, 5b and the gas blown to the back side of the tab 4b, 5b. Therefore, it is possible to more reliably suppress the vibration of the tab 4b, 5b, and thus to more effectively prevent the tab 4b, 5b from breaking.

[0100] (f) As shown in Figs. 21 and 22, a suction device 719 may be provided as a "suction means" at a position where the tabs 4b and 5b are sandwiched between the upstream blow device 715 (blowout ports 7151b and 7152b). The suction device 719 has a suction port 719b that opens toward the tabs 4b and 5b at a position adjacent to the tip of the tab 4b and 5b that is the target of the gas blown from the upstream blow device 715 along the flow direction of the gas blown from the upstream blow device 715, and is configured to be able to suck in the gas by the suction port 719b. By providing the suction device 719, it is possible to more reliably prevent the generation of turbulence as described above, and as a result, the effect of preventing the tabs 4b and 5b from breaking can be further improved. In addition, since the suction device 719 can suck in dust, the quality of the obtained battery element 1 can be improved more effectively.

[0101] (g) In the above embodiment, the tabs 4b, 5b are formed by cutting out a part of the electrode material (so-called formed tabs), but the configuration of the tabs is not limited to this. Therefore, the tabs 4b, 5b may be joined to the electrode main body parts 4a, 5b by welding (so-called welded tabs), for example. However, welded tabs are often relatively thick, and the tabs are relatively unlikely to swing. On the other hand, formed tabs are often thin, and the tabs are very likely to swing. Therefore, the winding device 10 in the above embodiment is particularly effective when the electrode sheets 4, 5 have formed tabs.

[0102] (h) In the above embodiment, the positional relationship maintaining mechanism 72 is provided immediately upstream of the transfer roller 711 along the transport path of the electrode sheets 4, 5, but the location of the positional relationship maintaining mechanism 72 may be changed as appropriate. Therefore, for example, the positional relationship maintaining mechanism 72 may be provided immediately downstream of the transfer roller 711 along the transport path of the electrode sheets 4, 5.

[0103] (i) In the above embodiment, the winding unit 11 is configured to include two winding cores 13, 14, but may be configured to include one winding core or three or more winding cores.

[0104] The outer peripheral shape of the winding core is not limited to those described in the above embodiment, and for example, the outer peripheral surface of the winding core may be circular or elliptical in a cross section perpendicular to the rotation axis of the winding core. Furthermore, the winding core may not have gaps between the core pieces. In addition, the electrode sheets 4, 5, etc. may be wound around a cylindrical core part provided on the outer periphery of the winding core.

[0105] (j) In the above embodiment, the battery element 1 of a lithium ion battery is manufactured by the winding device 10, but the wound element manufactured by the winding device 10 is not limited to this, and for example, a wound element of an electrolytic capacitor, etc. may be manufactured.

[0106] (k) The materials of the separator sheets 2, 3 and the electrode sheets 4, 5 are not limited to those in the above embodiment and may be changed as appropriate. Of course, the active material applied to the electrode sheets 4, 5 may be changed. [Explanation of symbols]

[0107] 1...lithium ion battery element (wound element), 2, 3...separator sheets, 4...positive electrode sheet (electrode sheet), 5...negative electrode sheet (electrode sheet), 4a, 5a...electrode main body, 4b, 5b...tab, 4c...positive electrode coating section (coating section), 5c...negative electrode coating section (coating section), 10...winding device, 13, 14...winding core, 711...transport roller, 715...upstream blow device (blow means), 716...roller outer periphery side blow device (roller outer periphery side blow means), 718...rectifying plate, 719...suction device (suction means), 719b...suction port.

Claims

1. A rotatable core is provided, A winding device that supplies a strip-shaped electrode sheet having an electrode main body having an active material on a surface thereof and a plurality of tabs protruding from widthwise edges of the electrode main body and provided at intervals along a longitudinal direction of the electrode main body, and a strip-shaped separator sheet made of an insulating material to the winding core while rotating the winding core, the winding core overlapping and winding the electrode sheet and the separator sheet, The electrode sheet is configured to be supplied to the winding core while being accelerated or decelerated, a rotatable transfer roller having an outer circumferential surface on which the electrode sheet is hung and defining a transfer path for the electrode sheet; a blowing means provided immediately upstream of the transfer roller in the transport direction of the electrode sheet, and capable of blowing gas from the base side to the tip side of the tab simultaneously onto both the front side and the back side of the tab.

2. The tab is provided on one end side of the electrode sheet in a width direction, the electrode sheet has a coated portion provided on the other end side of the electrode sheet in the width direction relative to the tab and coated with an active material, 2. The winding device according to claim 1, wherein a gas outlet of the blowing means is located closer to one end in the width direction of the electrode sheet than the coating portion.

3. 2. The winding device according to claim 1, further comprising a straightening plate provided at a position adjacent to the tip of the tab onto which the gas is blown from the blowing means, along the flow direction of the gas blown from the blowing means.

4. 2. The winding device according to claim 1, further comprising suction means having a suction port provided at a position adjacent to the tip of the tab that is the target of the gas blown from the blow means, along the flow direction of the gas blown from the blow means, and capable of sucking in the gas through the suction port.

5. The winding device according to claim 1, further comprising a roller outer periphery side blowing means provided in correspondence with the tab at the portion of the electrode sheet that is hung on the transfer roller, and capable of applying a force to the tab toward the rotation shaft of the transfer roller by blowing gas onto the tab.

6. 2. The winding device according to claim 1, wherein the electrode sheet is hung on the transport roller at a position immediately upstream of the transport roller in the transport direction of the electrode sheet, the electrode sheet being transported in a horizontal or oblique horizontal direction.

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