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 manufactured 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, which are stacked together with a separator sheet made of an insulating material interposed therebetween.

[0003] Known electrode sheets include an electrode body having an active material on its surface and tabs protruding from the widthwise edges of the electrode body, with multiple tabs spaced apart along the length of the electrode body.

[0004] Furthermore, a known winding device for manufacturing wound elements 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 freely rotatable transfer rollers on which the electrode sheet or the like is hung, and the transfer rollers serve to determine 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 address this problem, a technology 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). 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 being broken. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-35892 Summary of the Invention [Problem to be solved by the invention]

[0007] However, after extensive research, the inventors of the present invention have identified the following factors as the causes of the folding of the tab.

[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 tabs to oscillate along the thickness direction of the electrode sheet. When the oscillating tabs collide with the outer peripheral surface of the transport roller, they jump up, resulting in the tabs being bent.

[0009] In this regard, the technology described in Patent Document 1 does not solve the problem of the tab colliding with the outer circumferential surface of the transfer roller and being thrown up. In fact, the thrown up tab may collide with the deformation prevention member, causing deformation or breakage of 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, with specific effects of the corresponding means added as necessary.

[0012] Means 1. Equipped with a rotatable core, A winding device that supplies a strip-shaped electrode sheet, which includes an electrode main body having an active material on its surface and a plurality of tabs protruding from widthwise edge portions of the electrode main body and provided at intervals along the longitudinal direction of the electrode main body, and a strip-shaped separator sheet made of an insulating material to a winding core while rotating the winding core, and overlaps and winds 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 that is provided immediately upstream of the transfer roller in the conveying direction of the electrode sheet and that is capable of blowing gas from the base side of the tab toward the tip side thereof simultaneously onto both the front side and the back side of the tab.

[0013] According to the above-mentioned method 1, the electrode sheet is supplied to the core while being accelerated and decelerated. Therefore, vibrations and resonances caused by the acceleration and deceleration of the electrode sheet cause the tab to vibrate, which may result in the tab colliding with the outer peripheral surface of the transfer roller and causing the tab to break.

[0014] In this regard, according to the above-mentioned means 1, the blowing means can blow gas simultaneously onto both the front and back sides of the tab, from the base side of the tab toward the tip side. Therefore, even if the tab vibrates, the vibrating motion can be suppressed and the tab can be returned to its normal state. This more reliably prevents the tab from colliding with the outer circumferential surface of the transfer roller, and ultimately suppresses the tab from bouncing up due to the collision with the outer circumferential surface of the transfer roller. As a result, the tab can be effectively prevented from breaking.

[0015] Furthermore, since the tab is prevented from colliding with the outer peripheral surface of the transfer roller, the tab is prevented from breaking and can be maintained in good condition with less damage, thereby improving the quality of the wound element obtained.

[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, the coated portion being coated with an active material, The winding device according to means 1, wherein 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 method 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 located on the tab side, away from the coated portion. This more reliably prevents dust adhering to the coated portion from scattering when the gas hits the coated portion. As a result, the quality of the resulting wound element can be more effectively improved.

[0018] Means 3. The winding device described in Means 1, characterized in that it is provided with a straightening plate provided in 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 onto the front side of the tab and the gas blown onto the back side of the tab, which may have a negative 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 turbulence can be more reliably prevented by the current plate, and therefore the vibration of the tab can be more reliably suppressed, and in turn, the effect of preventing the tab from breaking can be further improved.

[0021] Means 4. A winding device according to Means 1, characterized in that it has a suction port provided in 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 that can suck in the gas through the suction port.

[0022] According to the above-mentioned method 4, the generation of the turbulence described above 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, which can more effectively improve the quality of the obtained wound element.

[0023] Means 5. A winding device according to 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 hooked onto the transport roller is deformed into a curved shape, and this deformation can cause the tabs to stand up. Such tab standing up can lead to damage to the tabs due to contact with peripheral devices or poor welding when welding multiple tabs together, which can result in a decrease in product quality (quality of the wound element) and productivity.

[0025] In this regard, the above-mentioned means 5 can more reliably prevent the tab from rising up by the gas blown toward the tab from the roller outer periphery side blowing means, thereby improving product quality and productivity.

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

[0027] According to the above-mentioned method 6, the electrode sheet is transported horizontally or diagonally horizontally 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, which may result in the tab being more likely to vibrate. If the tab is more likely to vibrate, 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 tab's vibration, and ultimately to extremely effectively prevent the tab from breaking, even under conditions where the tab's vibration is likely to occur, such as those of 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 horizontally or obliquely horizontally is hung on the transport roller at a position immediately upstream of the transport roller.

[0029] The technical matters relating to the above means may be combined as appropriate. For example, the technical matters relating to the above means 2 may be combined with the technical matters relating to the above means 5. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 2 is a perspective view showing a schematic configuration of a battery element. [Figure 2] FIG. 2 is a plan view showing a schematic configuration of a positive electrode sheet. [Figure 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. [Figure 5] FIG. 2 is a schematic 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. 6. [Figure 9] FIG. 7 is a partially enlarged cross-sectional view taken along line KK in FIG. 6. [Figure 10] FIG. 2 is a schematic front view of a correction unit. [Figure 11] FIG. 10 is a schematic diagram of a winding section when a separator sheet is placed in a gap in the winding core. [Figure 12] FIG. 10 is a schematic diagram of a winding section when cutting a separator sheet. [Figure 13] FIG. 10 is a schematic diagram of the winding section when winding of the electrode sheet and the like is completed. [Figure 14] FIG. 10 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. 10 is a schematic perspective view showing an upstream blow device and the like in another embodiment. [Figure 16] FIG. 10 is a schematic side view showing a plurality of pairs of upstream blow nozzles and the like in another embodiment. [Figure 17] FIG. 10 is a schematic perspective view showing a shielding plate and the like in another embodiment. [Figure 18] FIG. 10 is a schematic side view showing a shielding plate and the like in another embodiment. [Figure 19] FIG. 10 is a schematic perspective view showing a current plate and the like in another embodiment. [Figure 20] FIG. 20 is a partially enlarged cross-sectional view taken along line JJ in FIG. [Figure 21] FIG. 10 is a schematic perspective view showing a suction device and the like in another embodiment. [Figure 22] FIG. 22 is a partially enlarged cross-sectional view taken along line JJ in FIG. 21. DETAILED DESCRIPTION OF THE INVENTION

[0031] An embodiment will be described below with reference to the drawings. First, the structure 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 stacked 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. Furthermore, for convenience of explanation, hereinafter, 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 and 3 are strip-shaped and have the same width, and are made of an insulating material such as polypropylene (PP) to prevent the different electrode sheets 4 and 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, with, for example, an aluminum foil sheet being used for the positive electrode sheet 4 and a copper foil sheet being 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 electrode sheet 4, 5 includes an electrode main body 4a, 5a and a tab 4b, 5b. In this embodiment, the side of the electrode main body 4a where 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 where 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 coated with a positive electrode active material (e.g., lithium manganate particles) (the coated portions of the active material are indicated by a dotted pattern in Figures 2, 3, etc.). That is, the front and back surfaces of the positive electrode sheet 4 are provided with positive electrode coated portions 4c coated with the positive electrode active material. The positive electrode coated portions 4c are located closer to the other end of the positive electrode sheet 4 in the width direction than the tab 4b.

[0037] On the other hand, a negative electrode active material (for example, 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. While 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 bodies 4a and 5a, the active material may be applied to the entire area of ​​the electrode main bodies 4a and 5a. In other words, the coated portions 4c and 5c may be provided over the entire area of ​​the electrode main bodies 4a and 5a.

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

[0040] To obtain a lithium-ion battery, the battery element 1 is placed in a cylindrical metal 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 component (not shown), and the bundled tabs 5b are connected to a negative electrode terminal component (not shown). The two terminal components are then positioned to close both end openings of the battery container, thereby obtaining a lithium-ion battery.

[0041] Next, a description will be given of a winding device 10 for manufacturing the battery element 1. 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 within 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 raw sheet 32 ​​in which the positive electrode sheet 4 is wound in a roll shape. The positive electrode sheet raw sheet 32 ​​is supported so as to be freely rotatable, and the positive electrode sheet 4 is pulled out from there as needed.

[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 wrapped around its outer periphery and including transfer rollers 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 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 feeding the positive electrode sheet 4 to the winding unit 11 while holding it.

[0047] The sheet cutting cutter 74 is used to cut the positive electrode sheet 4. The cutting of the positive electrode sheet 4 is performed while the positive electrode sheet 4 is being held by the sheet insertion mechanism 73. The sheet cutting cutter 74 can be separated from the conveyance path of the positive electrode sheet 4 so as not to interfere with the supply of the positive electrode sheet 4 by the sheet insertion mechanism 73.

[0048] The tension applying mechanism 75 applies tension to the positive electrode sheet 4 and includes a plurality of rollers (e.g., dancer rollers). The operation of these rollers is controlled by the control device 91, thereby making it possible to adjust the tension applied by the tension applying mechanism 75 to the positive electrode sheet 4. In this embodiment, the tension applying mechanism 75 applies a constant tension to the positive electrode sheet 4 at all times. Note that 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 or a roller outer periphery 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 lifting roller disposed between the pair of rollers so as to be displaceable in the up and down direction, and is used 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 is provided, at its most upstream side, with a negative electrode sheet raw material 42 in which the negative electrode sheet 5 is wound in a roll shape. The negative electrode sheet raw material 42 is supported so as to be freely rotatable, and the negative electrode sheet 5 is pulled out from there as appropriate.

[0051] Further, in the middle of the conveyance path for the negative electrode sheet 5 from the negative electrode sheet raw roll 42 to the winding unit 11, 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, a buffer mechanism 76, and the like are provided, similar to the conveyance path for the positive electrode sheet 4. These are the same as those provided in the conveyance path for 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 raw rolls 52, 62 each formed by winding up the separator sheets 2, 3 in a roll shape. The separator raw rolls 52, 62 are supported so as to be freely rotatable, and the separator sheets 2, 3 are pulled out from them as appropriate.

[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 the same as that provided in the positive electrode sheet supply mechanism 31, except that it functions to apply tension to 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 mounted by a drive mechanism (not shown), two winding cores 13 and 14 spaced 180° apart in the rotational direction of the turret 12, two support rollers 15a and 15b positioned approximately 90° apart from the winding cores 13 and 14 in the rotational direction of the turret 12, a separator cutter 16, a pressure roller 17 for pressing down the various sheets 2 to 5 just before winding is completed, and a tape application mechanism 18 for applying a predetermined fixing tape. The winding unit 11 also includes a removal device (not shown) for removing the battery element 1 from the winding cores 13 and 14, located around a removal position P2 (described later).

[0055] The winding cores 13 and 14 are configured to rotate around 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 detected by an encoder (not shown), and information relating to the amount of rotation is input from the encoder to the control device 91.

[0056] Furthermore, winding cores 13 and 14 are provided so as to be able to protrude and retract from one of the tables constituting turret 12 along the axial direction of turret 12 (the depth direction of the paper in FIG. 5). When winding cores 13 and 14 protrude from one of the tables, their leading ends 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, 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, 14 have an elliptical shape in a cross section perpendicular to their rotation axis. Because the winding cores 13, 14 have a non-circular cross section, even when the winding cores 13, 14 are rotated at a constant speed, the various sheets 2-5 are supplied to the winding cores 13, 14 while being accelerated and decelerated. Immediately after the start of winding of the various sheets 2-5, the various sheets 2-5 are supplied to the winding cores 13, 14 while being accelerated, and immediately before the end of winding of the various sheets 2-5, the various sheets 2-5 are supplied to the winding cores 13, 14 while being decelerated.

[0058] Furthermore, the winding core 13 (14) has a pair of core pieces 13a, 13b (14a, 14b) that extend along the direction of their own rotation axis (the depth direction of the paper in FIG. 5). A gap 13c (14c) is formed between the core pieces 13a, 13b (14a, 14b). In addition, a chuck mechanism (not shown) is provided at the portion of the winding core 13 (14) that forms the gap 13c (14c) to clamp the separator sheets 2, 3 that are placed 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 to 5. The removal position P2 is a position where the winding cores 13, 14 are positioned when removing the various sheets 2 to 5 (i.e., the battery element 1) after winding.

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

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

[0062] The tape application mechanism 18 is for applying fixing tape to the end portions of the separator sheets 2 and 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 712, a bearing 713, a holder 714, an upstream blowing device 715, and a roller outer periphery side blowing device 716. In this embodiment, the upstream blowing device 715 constitutes the "blowing means," and the roller outer periphery side blowing device 716 constitutes the "roller outer periphery side blowing means."

[0064] As described above, the electrode sheets 4 and 5 are hung on the outer peripheral surface of the transfer roller 711, and the transfer roller 711 serves to determine the transport path of the electrode sheets 4 and 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 greater than the width of the electrode sheets 4 and 5, so that the entire width of the electrode sheets 4 and 5, including the tabs 4b and 5b, are hung on the outer peripheral surface of the transfer roller 711.

[0065] Furthermore, 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 that are transported horizontally or obliquely horizontally at a position immediately upstream of the transfer roller 711 along the transport direction of the electrode sheets 4, 5. At the position immediately upstream of this 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 to be unable to rotate around the rotation axis RA. However, 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 to both ends of the transfer roller 711 in the direction of the rotation axis RA, one on each side, 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 blowing device 715 is provided immediately upstream of the transfer roller 711 in 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 blowing device 715 constitutes the "blowing means."

[0070] The upstream blowing device 715 includes a first blowing device 7151 corresponding to the front side of the electrode sheets 4 and 5, and a second blowing device 7152 corresponding to the back side of the electrode sheets 4 and 5 (see FIGS. 7 and 8). In FIG. 8 and other figures, the tabs 4b and 5b may have a checkered pattern, and the coated areas 4c and 5c may be indicated by thick lines. Each blowing device 7151 and 7152 includes a relatively thin, cylindrical upstream blowing nozzle 7151a and 7152a with outlets 7151b and 7152b at their tips. Gas (e.g., inert gas) can be supplied into each upstream blowing nozzle 7151a and 7152a from a predetermined air supply device (not shown).

[0071] The 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 upstream blow nozzles 7151a, 7152a are arranged in parallel, and their blowout ports 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 coated 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 toward both the front and back sides of the tabs 4b, 5b from the base side (the electrode main body 4a, 5a side) of the tabs 4b, 5b toward the tip side. Note that in this embodiment, the gas is configured to blow from each outlet 7151b, 7152b with the same volume and speed.

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

[0074] The roller outer periphery side blowing device 716 is provided in correspondence with the tabs 4b, 5b at the portions 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 side blowing device 716 constitutes the "roller outer periphery side blowing means."

[0075] The roller outer periphery blowing 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. Furthermore, a configuration is made such that gas can be supplied into each outer periphery blow nozzle 7161 from the air supply device.

[0076] Furthermore, each outer peripheral 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 thereof is configured to face the tabs 4b and 5b (see FIG. 9). Note that, like the blowout ports 7151b and 7152b, the gas supply port 7161b is configured to be located closer to the other end of the electrode sheets 4 and 5 in the width direction than the coating sections 4c and 5c.

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

[0078] Furthermore, in this embodiment, gas is constantly supplied from the air supply device to each outer peripheral blow nozzle 7161, and when the tabs 4b, 5b reach a position in front 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 also be adopted in which gas is supplied from the air supply device into the outer peripheral blow nozzle 7161 every time the tabs 4b, 5b reach a position in front of the gas supply port 7161b. In other words, a configuration may also be adopted in which gas is blown toward the tabs 4b, 5b only when the tabs 4b, 5b reach a position in front 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 maintains 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, multiple 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 widthwise positional deviation of the electrode sheets 4, 5 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 that can detect the widthwise position of the electrode sheets 4, 5, and information related 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 by the correction actuator around a pivot center α at the top center of the upper roller 722a. The control device 91 controls the correction actuator to rotate the correction unit 722, thereby correcting misalignment of the electrode sheets 4, 5. This more reliably prevents variations in the relative positional relationships between the electrode sheets 4, 5 (particularly, the tabs 4b, 5b) and the upstream blowing device 715 (particularly, the blowing ports 7151b, 7152b) and the roller outer periphery side blowing device 716 (particularly, the gas supply port 7161b). As a result, it becomes possible to more reliably blow gas from the upstream blowing device 715 and the roller outer periphery side blowing device 716 in an appropriate state 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. With the separator sheets 2 and 3 stretched across the support rollers 15a (15b), one of the winding cores 13 (14) positioned at winding position P1 is extended from one of the tables of the turret 12, thereby placing the separator sheets 2 and 3 in the gap 13c (14c) of the winding core 13 (14) (see FIG. 11). Next, the chucking mechanism clamps the separator sheets 2 and 3 placed in the gap 13c (14c). Then, the one of the winding cores 13 (14) is rotated a predetermined number of times, thereby winding a predetermined amount of the separator sheets 2 and 3 onto 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 to 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 to 5. The winding of the various sheets 2 to 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 to 5, the various sheets 2 to 5 are accelerated and supplied to the winding cores 13, 14. After a certain time has elapsed since the start of winding the various sheets 2 to 5, the winding cores 13, 14 begin to rotate at a constant speed, and the various sheets 2 to 5 are supplied to the winding cores 13, 14 while accelerating and decelerating.

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

[0087] Next, a 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 Figure 12). After that, 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 Figure 13). The obtained battery element 1 is removed from the winding core 13 (14) by the removal device.

[0088] As described above, according to this embodiment, the upstream blowing device 715 can blow gas toward both the front and back sides of the tabs 4b and 5b simultaneously, from the base side of the tabs 4b and 5b toward the tip side. Therefore, as in this embodiment, the electrode sheets 4 and 5 are supplied to the winding cores 13 and 14 while being accelerated and decelerated. Therefore, even under conditions that tend to cause the tabs 4b and 5b to oscillate, the oscillated movement of the tabs 4b and 5b can be suppressed and the tabs 4b and 5b can be returned to their normal state. This more reliably prevents the tabs 4b and 5b from colliding with the outer peripheral surface of the transfer roller 711, thereby suppressing the tabs 4b and 5b from jumping up due to the collision with the outer peripheral surface of the transfer roller 711. As a result, bending of the tabs 4b and 5b can be effectively prevented.

[0089] Furthermore, since the tabs 4b, 5b are prevented from colliding with the outer peripheral 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, thereby improving the quality of the obtained battery element 1.

[0090] In addition, the gas outlets 7151b, 7152b of the upstream blowing device 715 are located closer to one end of the width direction of the electrode sheets 4, 5 than the coated sections 4c, 5c. In other words, when the electrode sheets 4, 5 are viewed in plan, the gas outlets 7151b, 7152b are located on the tabs 4b, 5b side, away from the coated sections 4c, 5c. This more reliably prevents dust adhering to the coated sections 4c, 5c from scattering when the gas hits the coated sections 4c, 5c. As a result, the quality of the resulting battery element 1 can be more effectively improved.

[0091] Furthermore, the portions of the electrode sheets 4, 5 that are hung on the transfer roller 711 are deformed into a curved shape, and this deformation can cause the tabs 4b, 5b to rise, but 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] Additionally, in this embodiment, at least one transfer roller 711 is adapted to receive the electrode sheets 4, 5 transported horizontally or diagonally. Therefore, the tabs 4b, 5b are likely to sag due to gravity at a position immediately upstream of the transfer roller 711, which may result in the tabs 4b, 5b easily vibrating. However, by providing the upstream blowing 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 blowing device 715 and the roller outer periphery side blowing device 716 and the positive electrode sheets 4 and 5 hung on the transfer roller 711 in an appropriate state. This makes it possible to more reliably blow gas from the upstream blowing device 715 and the roller outer periphery side blowing device 716 toward the target positions (predetermined positions of the tabs 4b and 5b) in an appropriate state, and more reliably suppress the vibration of the tabs 4b and 5b. As a result, the effect of preventing the tabs 4b and 5b from breaking can be further improved, and the condition of the tabs 4b and 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, the 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, the upstream blow nozzles 7151a, 7152a may be configured to be inclined with respect to the width direction of the electrode sheets 4, 5, with their outlets 7151b, 7152b facing the tabs 4b, 5b. Even with 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. For example, as shown in Fig. 15, the upstream blow nozzles 7151a, 7152a may be rectangular tubular. Furthermore, for example, the outer periphery blow nozzle 7161 may be curved 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. This configuration can further enhance the effect of suppressing the vibration of the tabs 4b, 5b.

[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 gas is blown by adjacent blow nozzles 7151a, 7152a, and 7161 along the conveyance direction of the electrode sheets 4 and 5. By providing the shielding plate 717, interference between the gases blown from the blow nozzles 7151a, 7152a, and 7161 can be more reliably prevented, further enhancing 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 between the upstream blow nozzle 7151a and the outer peripheral blow nozzle 7161. However, a shielding plate 717 may also be provided between multiple upstream blow nozzles 7151a or between multiple outer peripheral blow nozzles 7161. Of course, multiple shielding plates 717 may also 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 blowing device 715, along the flow direction of the gas blown from the upstream blowing device 715, and arranged in line with 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. This makes it possible to more reliably suppress the vibration of the tab 4b, 5b, and ultimately to further improve the effect of preventing 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 (air outlets 7151b and 7152b). The suction device 719 has suction ports 719b that open toward the tabs 4b and 5b and are located adjacent to the tips of the tabs 4b and 5b, onto which the gas is blown, along the flow direction of the gas blown from the upstream blow device 715. The suction ports 719b are configured to suck the gas. By providing the suction device 719, the generation of turbulence as described above can be more reliably prevented, thereby further improving the effectiveness of preventing the tabs 4b and 5b from breaking. Furthermore, the suction device 719 can suck dust, further improving the quality of the resulting battery element 1.

[0101] (g) In the above embodiment, the tabs 4b, 5b are formed by cutting out a portion 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 portions 4a, 5b by welding (so-called welded tabs), for example. However, welded tabs are often relatively thick, making tab vibration less likely to occur. On the other hand, formed tabs are often thin, making tab vibration more likely to occur. 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 and 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 and 5.

[0103] (i) In the above embodiment, the winding unit 11 is configured to include two winding cores 13 and 14, but it may be configured to include one 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 may be, for example, a circular or elliptical shape 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. Additionally, the winding core may be configured such that the electrode sheets 4, 5, etc. are 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, the wound element of an electrolytic capacitor, etc. may also 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 also be changed. [Explanation of symbols]

[0107] 1...lithium ion battery element (wound element), 2, 3...separator sheet, 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...transfer roller, 715...upstream blowing device (blowing means), 716...roller outer periphery side blowing device (roller outer periphery side blowing means), 718...rectifying plate, 719...suction device (suction means), 719b...suction port.

Claims

1. It has a rotatable core, A winding device that supplies a strip-shaped electrode sheet, which includes an electrode main body having an active material on its surface and a plurality of tabs protruding from widthwise edge portions of the electrode main body and provided at intervals along the longitudinal direction of the electrode main body, and a strip-shaped separator sheet made of an insulating material to a winding core while rotating the winding core, and overlaps and winds 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 that is provided immediately upstream of the transfer roller in the conveying direction of the electrode sheet and that is capable of blowing gas from the base side of the tab toward the tip side thereof 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 the 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, the coated portion being coated with an active material, 2. The winding device according to claim 1, wherein 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.

3. 2. The winding device according to claim 1, further comprising a straightening plate provided in 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 that has a suction port provided in a position adjacent to the tip of the tab that is the target for the gas to be blown from the blowing means, along the flow direction of the gas blown from the blowing means, and that is capable of sucking in the gas through the suction port.

5. The winding device according to claim 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.

6. 2. The winding device according to claim 1, wherein the electrode sheet is wound around the transfer roller at a position immediately upstream of the transfer roller along the direction of transport of the electrode sheet, the electrode sheet being transported horizontally or obliquely horizontally.

Images