JP2014170653A - Method and apparatus for preparing electrode sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for preparing an electrode sheet by which a number of high quality electrode sheets are prepared in a short time.SOLUTION: A method for preparing an electrode sheet comprises the steps of: preparing first and second separators 121 and 122 (120) sent out so as to overlap with each other from a state of being wound in a roll; sandwiching positive electrode plates 110 between the separators, while continually sending out the separators, with a predetermined interval provided in the separator sending-out direction, the plates having a shorter width than the separators; partially depositing, in the width direction of the separator, the overlapping part of the separators between the positive electrode plates in the separator conveying direction; and cutting the overlapping part of the separator by using a separator cutting unit 60 including a cutter drum and a cutter receiving drum, the cutter drum having a saw blade cutter 650 having a predetermined pitch, a separator presser arranged in front and back of the cutter in the cutter drum circumferential direction and biasing means for supporting the separator presser, and the cutter receiving drum having a cutter receiver 670 formed of an elastic body having a predetermined hardness.

Description

  The present invention relates to a method and an apparatus for producing an electrode sheet that constitutes a constituent element of a secondary battery used for a battery of, for example, a notebook personal computer, a hybrid vehicle, and an electric vehicle.

  2. Description of the Related Art Conventionally, a method and an apparatus for producing an electrode sheet that constitutes a constituent element of a secondary battery used for a battery of, for example, a notebook personal computer, a hybrid vehicle, and an electric vehicle are known (see, for example, Patent Document 1 and Patent Document 2) ).

  The electrode sheet disclosed in Patent Document 1 is alternately placed on the upper surface of the lower separator that has been conveyed by the conveyor and unwound from the lower separator unwinding portion, via the adsorption portion of the moving hand, and then The upper separator unrolled from the upper separator unwinding section is overlapped via a nipple roll, and the electrode plates accommodated by sandwiching the positive electrode plate and the negative electrode plate inside by two separators are alternately overlapped by a swing mechanism. Thus, a laminated portion is formed.

JP 2012-74402 A JP 2012-204070 A

  When an electrode sheet is to be produced using the electrode sheet producing apparatus disclosed in Patent Document 1, the positive electrode plate and the negative electrode plate are separated from each other in order to place the positive electrode plate and the negative electrode plate on each separator while accurately positioning them. It is necessary to stop the separator transport device every time it is placed on the substrate. If such an intermittent feeding operation of the separator is performed, the production efficiency of the electrode sheet is remarkably lowered, and the separator itself on the conveyor is suddenly stopped or the movement of the separator itself due to the sudden movement start operation, the separator and the separator A special structure is required to prevent the relative displacement between the stacked positive electrode plates and negative electrode plates.

  The reason for this is that if such a misalignment occurs, it will be rejected from the line as a defective product and the yield will decrease, or if it is a product, it will be a defective product and the electrodes will contact each other, causing a short circuit and an accident. This may be a cause.

  On the other hand, the electrode sheet creating apparatus disclosed in Patent Document 2 is in view of the problem of reduction in electrode sheet production efficiency due to the intermittent feeding operation of the separator of the electrode sheet creating apparatus disclosed in Patent Document 1. The purpose of the invention is to improve the production efficiency of the electrode sheet by continuously producing the electrode sheet.

  However, in the configuration disclosed in Patent Document 2, a slip ring is attached to a cutter cylinder, which is a rotating body, in order to create an electrode sheet by fusing a continuous separator with a cutter cylinder provided with a heat cutter on a roll peripheral surface. There is a problem that the power of the apparatus must be supplied using a device, etc., and the structure of the apparatus is complicated and the cost is increased. In addition, when the cutter cylinder rotates at high speed, the method in which the separator is melted by heat when compared to a method in which the separator is mechanically cut using a cutter or the like reduces the time for the heat cutter to apply heat to the separator. For this reason, there is a problem that a large disturbance occurs on the cut surface, and it becomes impossible to cut within a desired accuracy range along the cut line as designed.

  An object of the present invention is to provide an electrode sheet producing method and an producing apparatus capable of producing a large number of electrode sheets excellent in product quality within a predetermined time.

In order to solve the above-described problem, a method for producing an electrode sheet according to claim 1 of the present invention is as follows.
A method for producing an electrode sheet used for a secondary battery having a structure in which a positive electrode plate and a negative electrode plate are laminated while being insulated from each other via a separator made of an insulating sheet,
Prepare a first separator and a second separator that are each wound in a roll shape and sent out so as to overlap each other from the state wound in the roll shape,
While the first separator and the second separator are continuously sent out, a positive electrode plate having a length in the width direction perpendicular to the separator running direction is shorter than that of the separator between these separators. Sandwiched at a predetermined interval
The positive electrode plates sandwiched between the two separators are partially welded at both sides in the width direction corresponding to the width direction of the separator and overlapping portions of the separators at a predetermined interval in the running direction of the separator. And partially welding the overlapping portion of the separators between the positive plates in the running direction of the separator at a predetermined interval in the width direction of the separator,
Cutter barrel having a structure provided with a saw blade-shaped cutter having a predetermined pitch, a separator press disposed in the front and rear of the cutter in the circumferential direction, and an urging means for supporting the separator press, and a predetermined hardness Prepare a separator cutting device consisting of a cutter receiving cylinder having a structure provided with a cutter receiver made of an elastic body,
Rotating the cutter cylinder and cutter receiving cylinder of the cutting apparatus so that the circumferential surfaces of the cutter cylinder and cutter receiving cylinder of the cutting apparatus are in the same direction as the traveling direction of the separator,
The two separators that are continuously sent out are arranged side by side at a predetermined interval in the running direction of the separator in a state where the separator is sandwiched between the separator presser of the cutter cylinder and the cutter receiver of the cutter receiver cylinder. By cutting the overlapped portion of the separator located between the positive electrode plates with a saw blade cutter having a predetermined pitch, the front and back of the positive electrode plate are sandwiched between two separators and the periphery is the overlapped portion of the separator It is characterized in that an electrode sheet surrounded by is created.

Moreover, the preparation apparatus of the electrode sheet of Claim 3 of this invention is
An electrode sheet producing apparatus used for a secondary battery having a structure in which a positive electrode plate and a negative electrode plate are laminated while being insulated from each other via a separator made of an insulating sheet,
A separator supply device for feeding the continuous first separator and the second separator wound in a roll shape so as to overlap each other from the state wound in the roll shape;
A positive electrode plate supply device that supplies a positive electrode plate whose length in the width direction perpendicular to the separator travel direction is shorter than that of the first separator and the second separator;
A positive plate transport device for transporting the positive plate supplied by the positive plate supply device to a predetermined position;
A sandwiching device for sequentially sandwiching the positive electrode plate conveyed by the positive electrode plate conveyance device so as to be separated by a predetermined interval in the separator delivery direction between the two fed-out separators;
The positive electrode plates sandwiched between the two separators are partially welded at both sides in the width direction corresponding to the width direction of the separator and overlapping portions of the separators at a predetermined interval in the running direction of the separator. And a welding device that partially welds the overlapping portion of the separators between the positive plates in the running direction of the separator at a predetermined interval in the width direction of the separator;
A cutter body having a structure provided with a saw blade-shaped cutter having a predetermined pitch, a separator press disposed in the circumferential direction of the cutter, and an urging means for supporting the separator press, and a predetermined hardness A separator cutting device comprising a cutter receiving cylinder having a structure provided with a cutter receiver made of an elastic body having a circumferential surface of the cutter cylinder and the cutter receiving cylinder of the cutting device in the same direction as the traveling direction of the separator Equipped with a rotating cutting device,
An overlapping portion of the separators positioned between the positive electrode plates arranged side by side at a predetermined interval in the running direction of the two continuous separators that are sent out continuously is provided as a separator presser of the cutter cylinder and the cutter receiver. By cutting with a saw blade cutter having a predetermined pitch in a state where the separator is sandwiched between the barrel cutter receiver, the front and back of the positive electrode plate are sandwiched between two separators and the periphery is surrounded by the overlapping portion of the separators It is characterized by producing an electrode sheet.

Moreover, the preparation method of the electrode sheet which concerns on Claim 2 of this invention is the preparation method of the electrode sheet of Claim 1,
The pitch of the saw portion of the saw blade cutter is 0.5 mm to 1 mm, and the difference in height between the peaks and valleys is 0.4 mm to 0.9 mm.

Moreover, the electrode sheet producing apparatus according to claim 4 of the present invention is the electrode sheet producing apparatus according to claim 3,
The pitch of the saw portion of the saw blade cutter is 0.5 mm to 1 mm, and the difference in height between the peaks and valleys is 0.4 mm to 0.9 mm.

  According to the present invention, the electrode plates are sequentially sandwiched between the first separator and the second separator that are fed so as to overlap each other from the state of being wound in a roll shape, and then adjacent to each other. The welded part of the separators between the electrode plates to be welded is partially welded, and then the separators are placed in front and back in the circumferential direction of the cutter. And a separator cutting device comprising a cutter receiving cylinder provided with an elastic body such as rubber having a predetermined hardness, for example, and a predetermined pitch provided on the cutter cylinder. Cutting is performed by a saw blade cutter.

  By having such a configuration in the present invention, by rotating the outer peripheral surface in the traveling direction as the separator travels between the cutter cylinder and the cutter receiving cylinder, the electrode sheet is not intermittently continuous as in the prior art. Thus, the production efficiency of the electrode sheet can be remarkably improved.

  In general, a separator made of an insulating sheet made of resin is cut with a saw blade cutter while sandwiched between a separator holder provided on the cutter cylinder and a cutter holder made of an elastic body such as rubber provided on the cutter holder cylinder. By doing so, the blade edges of a large number of saw blade cutters simultaneously strike a predetermined cutting line (a portion to be cut) of the separator according to such a cutting method. That is, a number of cutting edges of the saw blade cutter simultaneously make point contact with the cutting portion of the separator, and the saw blade cutter is pressed against the separator, so that all the cutting edges of each saw blade of the saw blade cutter have the separator almost simultaneously. In addition, a perforated cutting start portion (cutting start line) is first formed in the portion of the separator to be cut through. Then, the cutter is further pressed against the separator while the separator is sandwiched between the separator holder and the cutter holder, so that the width gradually increases toward the edge of the saw blade cutter, and all the blades of each saw blade are The separator is cut in the cutting direction while each through hole of the separator constituting the perforated cutting start portion is expanded in a slit shape with a so-called wedge effect.

  In this manner, while maintaining the state where the separator is sandwiched between the separator presser and the cutter holder, the portion to be cut of the separator starting from the through hole is simultaneously cut into fine slits in the cutting direction of the separator. Eventually, the edge of the saw blade cutter reaches the entire cutting line of the separator and completely cuts the separator.

  According to the present invention, since the cutting start portion of the separator is formed over the entire width direction of the separator by the cutting principle as described above, the installation status of the cutting device, the feeding speed of the separator, and the state of the cutter need not be strictly managed. The separator can be cut along the cutting line according to the design dimensions.

  In particular, the separator of the electrode plate is generally made of resin and has a property of being easily stretched, but according to the present invention, the tip of the cutter is in line contact as in the case of using a cutter having a straight tip. Since the cutter is not pressed against the separator to cut it, the cut portion of the separator does not extend in the running direction of the separator.

  More specifically, since it is made of polypropylene or polyethylene generally made of porous material in order to have a shutdown effect, when the cutter is pressed against the separator in a state where the cutter blade is in line contact with the separator, the separator In some cases, the cutting portion of the cutter may extend with respect to the traveling direction of the cutter. When elongation of the separator occurs, it becomes difficult to produce a large number of electrode sheets in which the edge of the separator satisfies the specified dimension. However, according to the present invention, the separator does not grow, and the separator A large number of electrode sheets in which the edge portion satisfies the specified dimension can be produced.

  In addition, by using a saw blade-like cutter with a fine pitch and a cutter receiving rubber having an appropriate hardness, it becomes possible to obtain a cutting accuracy of 0.1 mm and a desired cut surface.

  ADVANTAGE OF THE INVENTION According to this invention, the preparation method and preparation apparatus of an electrode sheet which can produce many electrode sheets excellent in product quality stably for the predetermined time can be provided.

It is a schematic side view of the electrode sheet preparation apparatus for secondary batteries used for preparation of an electrode sheet. It is sectional drawing which cut | disconnected the separator cutting device of the preparation apparatus of the electrode sheet which concerns on one Embodiment of this invention along the direction orthogonal to the center axis line of the cutter cylinder and a cutter receiving cylinder. FIG. 3 is a schematic cross-sectional view corresponding to FIG. 2 showing a state before the cutter cylinder and the cutter receiving cylinder of the cutting apparatus shown in FIG. 2 cut the separator. It is a cutting process figure which shows in order until the state from which the cutting device shown in FIG. 3 cut | disconnects a separator completely from the state of FIG. It is a top view of the electrode sheet created by the creation method of the electrode sheet concerning this embodiment. FIG. 6 is a detailed view of the α part of the electrode sheet shown in FIG. 5, and is a plan view partially showing a state immediately before cutting a separator sandwiching each positive electrode plate (FIG. 6 (a)) and FIG. 6 (a). FIG. 7 is an enlarged plan view (FIG. 6B) showing the left electrode sheet of FIG. 6A immediately after cutting the separator shown in FIG. An explanatory view (FIG. 7 (a)) showing a state immediately after the overlapping portion of the separator is cut by a normal cutter instead of the saw blade cutter, and the separator overlap using the saw blade cutter according to the present embodiment. It is explanatory drawing (FIG.7 (b)) which shows the state immediately after cut | disconnecting a part.

  Hereinafter, an electrode sheet creation method and creation apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing an overall configuration of a secondary battery electrode sheet creating apparatus used in an electrode sheet creating method according to an embodiment of the present invention.

  The electrode sheet creating apparatus 1 for a secondary battery used in the electrode sheet creating method according to the present invention includes a positive plate supplying device 10, a positive plate conveying device 20, a separator supplying device 30, a sandwiching device 40, and welding. The apparatus 50, the cutting device 60, the inspection device 70, the defective product discharge device 80, and the stacking device 90 are provided.

  The positive electrode plate supply device 10 is for supplying positive plates one by one to the positive electrode plate conveyance device 20 one by one at regular time intervals, and the positive electrode plate conveyance device 20 is supplied from the positive electrode plate supply device 10. The positive plates are conveyed so that the positive plates are separated from each other by a predetermined distance, and supplied to the sandwiching device 40 one by one.

  The separator supply device 30 is for supplying two continuous separators wound in a roll, and has an upper-stage separator supply device 30U and a lower-stage separator supply device 30L. A tension control device (not shown) is provided on each of the upper side and the lower side, and a constant tension is applied when the upper side separator and the lower side separator are overlapped while the positive electrode plate is being sandwiched by the clamping device 40. The electrode sheet is prepared in such a way that the separator is not wrinkled, loosened, stretched or the like.

  The sandwiching device 40 sequentially sandwiches the positive plates conveyed from the positive plate conveyance device 20 between the continuous separators respectively supplied from the upper-stage separator supply device 30U and the lower-stage separator supply device 30L, with a predetermined interval therebetween. belongs to. The sandwiching device 40 sandwiches the positive electrode plate between an upper separator supplied from an oblique upper side and a lower separator supplied from an oblique lower part under predetermined arrangement conditions.

  The welding device 50 is for welding two upper and lower separators in a state where the positive electrode plate is sandwiched so that the positive electrode plate does not protrude from the separator. The parts are partially welded at a predetermined interval.

  The cutting device 60 is a device that cuts continuously connected electrode sheets in the width direction. The cutter includes a cutter that cuts the separator, a cutter cylinder that holds the cutter, and a cutter receiving cylinder that receives the cutter. The cutter cuts the overlapping portion between two adjacent positive electrode plates in the width direction perpendicular to the traveling direction of the separator. The detailed configuration of the cutting device 60 will be described later.

  The inspection device 70 is used to determine whether the electrode sheet cut by the cutting device 60 is good or bad. When the inspection device 70 determines that the electrode sheet is defective, the defective product discharge device 80 removes the defective electrode sheet. Is.

  The stacking device 90 is configured to stack electrode sheets that have passed as non-defective products by the inspection device 70 so as not to be displaced from each other.

  Next, the structure of the cutting device 60 of the electrode sheet creating apparatus 1 according to this embodiment will be described in more detail based on the drawings. FIG. 2 is a cross-sectional view of the cutting device of the electrode sheet producing apparatus according to one embodiment of the present invention cut along a direction perpendicular to the center axis of the cutter cylinder and the cutter receiving cylinder. FIG. 3 is a schematic cross-sectional view corresponding to FIG. 2 showing a state before the cutter cylinder and the cutter receiving cylinder of the cutting apparatus shown in FIG. 2 cut the separator.

  The cutting device 60 includes a cutter cylinder 610 having a saw blade cutter 650 and a cutter receiving cylinder 620 that receives the saw blade cutter 650. The cutter cylinder 610 and the cutter receiver cylinder 620 are arranged such that their axial directions are parallel to each other. As described above, the separator 120 is interposed between the cylinders. In addition, the distance for one round of the cutter drum circumferential direction of the portion of the cutter drum 610 where the saw blade cutter 650 is provided coincides with the length in the separator running direction between adjacent cutting lines of the separator 120. The cutter cylinder 610 and the cutter receiving cylinder 620 are respectively driven by a rotation driving means and a rotation driving force transmission means (not shown here), and the rotation speed positions on the outer circumferential surface and the circumferential speed of each other are adjusted by adjusting the rotation speed of each other. Rotate while matching.

  In addition, both ends of the cutter cylinder 610 and the cutter receiving cylinder 620 are closed, and the closed portions support the rotation shafts of the respective cylinders and transmit the driving force from the rotation driving means to each cylinder.

  The cutter body 610 is made of a metal and is formed of a cylindrical body partly circumferentially cut out along the longitudinal direction. The body 611 is further provided with a conductive surface treatment on the peripheral surface. A support body 630 fixed to the inner peripheral portion of the main body 611, and a cutter base 640 fixed to the support body 630 and provided with a saw blade cutter 650 and a separator presser 660 are provided. The length in the longitudinal direction of the cutter body 610 is longer than the width of the separator 120, and the length in the longitudinal direction of the support 630 is a length that can be sufficiently accommodated to bisect the separator 120 in the width direction. have.

  Although not shown here, the support body 630 is a long and narrow bar-shaped body made of metal and has a cutter base fixing portion 631 for fixing the cutter base 640 and the entire longitudinal direction of the support body 630. There is a mounting portion (not shown here) to which a saw blade cutter 650 having a length corresponding to this is attached with a fastener or the like.

  The cutter base 640 is made of metal and is attached to the support 630 described above. The cutter base 640 is originally divided into two parts by the first base part 641 and the second base part 642 and is fixed to the support body 630 integrally with a fastener such as a hexagon socket bolt 691. . The cutter base 640 sandwiches the saw blade cutter 650 in a state where the first base part 641 and the second base part 642 are integrated, and the coil springs 645 and 646 and the separator holders 661 and 662 inside the cutter base. An accommodating portion 640a capable of accommodating the base end portion of (660) is formed. The coil springs 645 and 646 are accommodated in the accommodating portion 640a of the cutter base 640, one end of which is pressed against the first base part 641, and the other end of each of the coil springs 645, 646 The row side separator retainers 662 are accommodated in parallel so as to be pressed against the proximal end side.

  The saw blade cutter 650 has a saw blade cutting portion whose length is longer than the width of the separator 120 to be cut and whose tip is small in pitch in the entire length direction, and is a fastener such as a bolt at a predetermined interval in the length direction. (Not shown) is firmly fixed to the cutter base 640. In addition, the specific dimension of the preferable pitch of the saw blade of the saw blade cutter 650 will be described later. The cutter base 640 is attached to the support 630 with the saw blade cutter 650 sandwiched as described above.

  In the case of this embodiment, the separator press 660 is made of a conductive resin member, and has a long and narrow preceding separator press 661 and a subsequent separator press that have a substantially L-shaped cross section in a direction orthogonal to the longitudinal direction. 662. The leading separator press 661 is disposed on the leading side preceding the saw blade cutter 650 with respect to the rotation direction of the cutter cylinder 610, and the trailing separator press 620 follows the saw blade cutter 650 with respect to the rotation direction of the cutter cylinder. Arranged on the side. In other words, the leading separator press 661 is positioned on the leading side with respect to the traveling direction of the separator 120 relative to the saw blade cutter 650, and the trailing separator press 662 is saw-toothed with respect to the traveling direction of the separator 120. It is located on the rear side of the cutter 650.

  In addition, each of the separator holders 661 and 662 has a wide spring receiving portion on the base end side thereof, and each of the separator pressers 661 and 662 receives the urging force of the coil springs 645 and 646 on the receiving portion 640a of the cutter base 640. Contained. Further, the separator presser 660 is fitted into a slit formed by a predetermined length in the longitudinal direction of the outer peripheral portion of the cutter base 640, and a part of the separator presser 660 is interposed through the urging force of the coil springs 645 and 646. It protrudes from the outer periphery. Further, the leading separator press 661 and the trailing separator press 662 of the separator pressing 660 are partitioned by a saw blade cutter 650 into the leading side and the trailing side in the rotational direction of the cutter body 610.

  The separator holder 660 protrudes from the outer peripheral surface of the cutter cylinder 610 unless a special force is applied to the separator holder 660, that is, unless a pressing force is applied from the cutter receiver rubber 670 of the cutter receiver cylinder 620 described later. Keeps the state.

  It should be noted that the leading end portions of the leading separator presser 661 and the trailing separator presser 662 that protrude from the cutter body 610 are pressed against a cutter receiving surface 671 formed on the outer peripheral surface side of a cutter receiving cylinder of a cutter receiving rubber 670 described later. Thus, a flat portion is formed.

  The cutter receiving cylinder 620 is formed of a cylindrical body having a peripheral surface subjected to surface treatment having the same shape as that of the cutter cylinder 610 made of metal. The cutter receiving cylinder 620 includes a slit 621 formed in the same central angle range in the longitudinal direction with respect to the cutter receiving cylinder 620. The slit 621 is longer than the saw blade cutter 650, and a cutter receiving rubber (cutter receiver) 670 having the same length as the slit 621 is fitted into the slit 621.

  In the case of the present embodiment, the cutter receiver rubber 670 is made of urethane rubber having a Shore hardness Hs of 85 to 90, and has a substantially square cross section in the direction orthogonal to the longitudinal direction. The cutter receiver rubber 670 is formed in the slit 621 of the cutter receiver cylinder 620. It consists of an elongated elastic member that is just fitted. As for the material of the cutter receiving rubber 670, it can withstand repeated cutting of the separator 120 in cooperation with the saw blade cutter 650, and also maintains the state in which the separator 120 is always firmly sandwiched in cooperation with the separator presser 660. Other elastic materials may be used as long as the material has a possible hardness.

  The cutter receiving surface 671 (see FIG. 2) of the cutter receiving rubber 670 exposed to the outside from the slit 621 does not protrude from the other outer peripheral surface of the cutter receiving cylinder 620, and the curvature of the cutter receiving surface 671 is the cutter receiving cylinder. The curvature of the outer peripheral surface of 620 is almost the same.

  Next, a specific cutting process of the separator 120 by the cutting device 60 will be described in time series based on the drawings. FIG. 4 is a cutting process diagram that sequentially shows from the state of FIG. 3 until the separator 120 shown in FIG. 3 completely cuts the separator 120. First, as shown in FIG. 4A, the separator 120 in a continuous state before cutting in a state where the separator 120 (see the two-dot chain line in the figure) is sandwiched between the cutter cylinder 610 and the cutter receiving cylinder 620. Travels to the left in the horizontal direction as indicated by the arrow on the left side of the figure, and is indicated by the arrow in the figure so that both the cutter cylinder 610 and the cutter receiving cylinder 620 have the same peripheral speed as the traveling speed of the separator 120. Rotate in the direction. In this state, the separator holder 660 of the cutter cylinder 610 and the cutter receiver rubber 670 are in a state before being pressed against each other, and the separator holder 660 protrudes from the peripheral surface of the cutter cylinder 610 and is a saw blade cutter 650. Is hidden in it.

  Next, as shown in FIG. 4B, when the cutter cylinder 610 and the cutter receiver cylinder 620 further rotate, the separator holder 660 and the cutter receiver rubber 670 approach each other, and the preceding separator holder 661 starts to hit the separator 120. However, the saw blade cutter 650 that has still protruded toward the peripheral surface of the cutter receiving cylinder 620 via the separator 120 is hidden by the separator holder 660.

  Next, as shown in FIG. 4 (c), when the cutter cylinder 610 and the cutter receiving cylinder 620 further rotate, the preceding separator press 661 (see FIGS. 2 and 3) of the separator press 660 of the cutter cylinder 610 removes the separator 120. Then, it starts to be pressed against the cutter receiving rubber 670 of the cutter receiving cylinder 620. That is, in this state, the leading separator press 661 (see FIGS. 2 and 3) of the separator press 660 starts to hit the cutter receiving rubber 670 via the separator 120 with respect to the rotation direction of the cutter body 610, and the movement of the separator 120 is restricted. To do.

  Next, as shown in FIG. 4D, when the cutter cylinder 610 and the cutter receiver cylinder 620 are further rotated slightly, the leading separator press 661 and the trailing separator press 662 of the separator holder 660 of the cutter cylinder 610 and the cutter receiver The separator 120 is sandwiched between the cylinder 620 and the cutter receiving rubber 670 and pressed completely. That is, the coil springs 645 and 646 that apply a biasing force to the separator presser 660 (661, 662) are compressed by the repulsive force received from the cutter receiving rubber 670 so that the separator presser 660 (661, 662) is in contact with the outer peripheral surface of the cutter barrel 610. While maintaining the state in which the separator 120 is sandwiched between the cutter receiving surface 671 and the cutter receiving surface 671 of the cutter receiving rubber 670 until they are flush with each other, the saw blade cutter 650 fixed to the cutter base 640 remains as it is. The saw blade cutter 650 is pressed against the overlapping portion 120a (see FIGS. 5 and 6A) of the separator 120 sandwiched between the cutter cylinder 610 and the cutter receiving cylinder 620. Separator between adjacent positive electrode plates while satisfying various conditions 0 superposition portion 120a is simultaneously and accurately cut by the respective saw blade sawtooth cutter 650.

  The separator 120 is firmly sandwiched between the leading cutter retainer 661 and the trailing cutter retainer 662 of the cutter retainer 660 of the cutter barrel 610 and the cutter receiving surface 671 of the cutter receiver rubber 670 of the cutter receiver barrel 620. Since the cutting is performed by the saw blade cutter 650 in a state where the separator traveling direction is also sandwiched between the preceding separator pressing member 661 and the trailing separator pressing member 662, the cutting line 120b according to the design dimension (FIG. 5 and FIG. 5). The separator 120 can be cut along the line (see FIG. 6A).

  That is, in this state, as shown in FIG. 2, the separator 120 is sandwiched between the cutter receiving rubber 670 by both the advancing side portion and the trailing side portion of the separator presser 660 in the rotational direction of the cutter body 610. Then, the separator press 660 is pushed in, and a saw blade cutter 650 appears, and each blade of the saw blade is cut between the separator press 660 and the cutter receiving rubber 670 to cut the separator 120, and the cutter receiving rubber 670 is cut. Bite into.

  The method of cutting the separator 120 at this time will be described in more detail. Generally, when cutting the separator 120 made of an insulating sheet made of resin, a saw blade is maintained while the separator 120 is firmly sandwiched between the separator holder 660 of the cutter cylinder 610 and the cutter receiver rubber 670 of the cutter receiver cylinder 620. Cutting of the separator 120 is started by the shape cutter 650. At this time, a large number of cutting edges of the saw blade cutter 650 simultaneously strike a predetermined cutting line 120 b of the separator 120. That is, in the state where the constant width region including all the cutting lines of the separator 120 is firmly sandwiched between the separator presser 660 and the cutter receiving rubber 670, the multiple blade edges of the saw blade cutter 650 are overlapped portions 120a of the separator 120. When the saw blade cutter 650 is pressed against the separator 120 at the same time by making point contact with the cutting line 120b located substantially in the center of the separator traveling direction, all the cutting edges of the saw blade cutter 650 penetrate the separator 120, and the separator A perforated cutting start portion is first formed at 120 cutting lines 120b.

  Then, when the saw blade cutter 650 is further pressed against the separator 120 while the separator 120 is sandwiched between the separator presser 660 and the cutter receiver rubber 670, a perforated cutting starts toward the blade edge of the saw blade cutter 650. The width of the part gradually expands, and all the blades cut the separator 120 in a predetermined manner while expanding each through hole of the separator 120 constituting the perforated cutting start part by a kind of so-called wedge effect. Cut along the line. Also in this case, the constant width region including all the cutting lines of the separator 120 was firmly sandwiched between the leading separator press 661 and the trailing separator press 662 of the separator press 660 and the cutter receiving surface 671 of the cutter receiving rubber 670. Since it is in a state, the cutting direction does not deviate from the designed cutting line 120b, and is cut in accordance with this.

  In this process, since the separator 120 is always kept firmly sandwiched between the separator presser 660 and the cutter receiving rubber 670, the cutting line 120b of the separator 120 starting from the through hole is in the cutting direction of the separator 120. At the same time, the slits are cut into fine slits at the same time, and eventually the vicinity of the blade edge of the saw blade cutter 650 reaches the cutting line 120b of the separator 120 to completely cut the separator 120.

  In this way, the overlapping portion 120a of the separator 120 is cut along the cutting line 120b without causing unexpected elongation or the like in a part of the separator 120 and without causing an uncut portion in a part of the separator 120. And cut as designed.

  Next, as shown in FIG. 4E, when the cutter cylinder 610 and the cutter receiving cylinder 620 are slightly rotated, the saw blade of the saw blade cutter 650 is cut into the cutting portion 120e of the separator 120 (FIGS. 6 and 7B). Begin to move away from That is, in this state, the trailing separator press 662 of the separator press 660 is finally separated from the separator 120 with respect to the rotation direction of the cutter body 610.

  Next, as shown in FIG. 4 (f), when the cutter cylinder 610 and the cutter receiving cylinder 620 further rotate and the separator 120 travels, the cut separator 120 is pushed out to the left in the figure, and the separator 120 is cut. The blade of the saw blade cutter 650 is completely separated from the portion, and the blade of the saw blade cutter 650 is separated from the cutter holder rubber 670 by the separator presser 660 by the biasing force of the coil springs 645 and 646 as shown in FIG. ), That is, the protruding portion protrudes from the outer peripheral surface of the cutter body 610, and the saw blade cutter 650 is hidden therein.

  Thus, by rotating the cutter cylinder 610 and the cutter receiving cylinder 620, the operation shown in FIGS. 4A to 4F described above is repeated each time the stack 120a of the separator 120 is moved. The separator press 660 and the cutter receiver rubber 670 are in a state of being sandwiched, and the same cutting operation is repeated.

  Note that, as described above, the distance of one round in the circumferential direction of the cutter body 610 at the portion where the saw blade cutter 650 of the cutter body 610 is provided is the separator traveling between the adjacent cutting lines of the separator 120 as described above. Match the length of the direction. As described above, the two separators 121 and 122 continuously fed between the cutter body 610 and the cutter receiving body 620 and the positive plates 110 sandwiched between the separators at a predetermined interval are adjacent to each other. The dimensions of the separator overlapped portion 120a between the separator cylinder 610 and the cutter receiver rubber 670 of the cutter cylinder 610 are held by the saw blade cutter 650 and the separator 120, which is generally made of resin, is not stretched. Cut to the street.

  Next, an electrode sheet created by the electrode sheet creation method according to the above-described embodiment will be described with reference to the drawings. In addition, the arrow shown rightward in drawing of FIG. 5 represents the traveling direction of the separator in electrode sheet preparation.

  FIG. 5 is a plan view showing the electrode sheet 100 created by the electrode sheet creation method according to the present embodiment. FIG. 6 is a detailed view of the α part of the electrode sheet 100 shown in FIG. 5, and shows a state immediately before the separator 120 (121, 122) sandwiching the positive electrode plate 110 is cut into each electrode sheet 100. 6A and the electrode sheet 100 on the left side of FIG. 6A immediately after cutting the separator 120 shown in FIG. 6A along the cutting line indicated by a two-dot chain line is enlarged. FIG. 6 is a plan view (FIG. 6B).

  The state before the separator cutting of the electrode sheet 100 produced by the electrode sheet producing apparatus according to the present embodiment is as follows. As shown in FIG. 6A, the two positive electrode plates 110 are separated from each other by a predetermined distance. After being sandwiched between 121 and 122, the separator 120 between the adjacent positive electrode plates 110 is overlapped with the overlapping portion 120 a in a direction orthogonal to the extending direction of adjacent edge portions of each positive electrode plate 110, that is, the separator 120 travels. A plurality of rectangular welded portions 131 and 132 having a longitudinal direction as the direction are formed in parallel with a distance from each other in the width direction of the separator 120. Similar welded portions 135 and 136 are also formed on the overlapping portions 120 a on both sides in the width direction of the separator 120. Then, the overlapping portion 120a of the separator 120 between the welded portions 130 (131, 132) is cut by the saw blade cutter 650 of the cutting device 60 along the cutting line indicated by the two-dot chain line in FIG. An individual electrode sheet 100 having jagged cutting portions 120e (see FIG. 6B) with extremely small pitches corresponding to the blades of a saw blade cutter at the two opposing edges of the electrode sheet 100 is produced. (See FIG. 6B).

  Subsequently, when the cutting device 60 with the saw blade cutter 650 according to the above-described embodiment is used and when such a saw blade cutter 650 is not used, that is, a general configuration in which the cutting edge is simply a straight line. The state after cutting the separator in the case of using a normal cutter will be described. FIG. 7 is an explanatory view (FIG. 7A) showing a state immediately after cutting the overlapping portion 120a of the separator 120 with a normal cutter instead of the saw blade cutter, and the saw blade cutter according to this embodiment. It is explanatory drawing (FIG.7 (b)) which shows the state immediately after cut | disconnecting the overlap part 120a of the separator 120 using.

  As can be seen from FIG. 7, when the overlapping portion 120 a of the separator 120 is cut with a normal cutter, a portion 120 s that is completely cut in the separator width direction of the cutting line and a cut line that is not cut completely yet. The portion 120c that is not completely cut out so as to contain a gap is mixed, and the overlapping portion 120a of the separator between the adjacent positive electrode plates cannot be completely divided into two. In addition, the completely cut portion 120s could not be cut smoothly in a straight line according to the design dimensions due to the elongation of the separator during cutting.

  On the other hand, when the saw blade cutter 650 of the present embodiment is used, as shown in FIG. 7 (b), the separator between the positive plates adjacent to each other has a jagged cut portion 120e having a small pitch in all the cut portions of the separator. The overlapping portion 120a of the separator was completely bisected. The difference between the two is considered to have occurred based on the cutting principle of the present invention in FIG.

  Finally, preferable shapes and dimensions of the saw blade cutter used in the electrode sheet manufacturing method according to the present invention will be described. As this preferable shape and size, each saw blade has an equilateral triangle shape, and the pitch of the saw blade is 1 mm. In this case, since the saw blade is an equilateral triangle, the height of the saw blade is about 0.9 mm. On the other hand, when the pitch is 2 mm, if the saw blade is an equilateral triangle, the height of the saw blade is about 1.8 mm. And when the separator was cut using both saw blades, it was confirmed that the saw blade with finer pitch can cut according to the dimensions without causing excessive elongation at the cutting portion of the separator. It was. Therefore, it was found that the saw blade cutter according to the present embodiment preferably has such a small pitch. In addition, when the inventor of the present invention examined the relationship between the pitch of the saw portion and the height of the peaks and valleys of the most preferable saw blade cutter according to the present embodiment, the pitch was 0.5 mm and the heights of the peaks and valleys. As a result of observing the state of the separator that was actually cut, the difference of 0.4mm to the pitch of 1mm and the difference in height between the peaks and valleys was in the range of 0.9mm. It turns out to get. However, even when the pitch is 2 mm, in the case of the present invention, the separator is cut by the saw blade cutter while being sandwiched between the separator holder of the cutter cylinder and the cutter receiver of the cutter receiver cylinder. It is considered that a cut portion having better quality than that of a conventional electrode sheet can be formed.

  The shapes, dimensions, numerical values, and materials of the components introduced in the above-described embodiments are merely examples, and various shapes, dimensions, numerical values, and materials are appropriately selected without departing from the scope of the present invention. Needless to say, you can. That is, the method for producing an electrode sheet in the present invention is not realized by being limited to the configuration of the electrode sheet producing apparatus described above.

  Moreover, although this embodiment demonstrated the preparation method and preparation apparatus of the electrode sheet of the structure which inserts a positive electrode plate between two separators, preparation of the electrode sheet of the structure which inserts a negative electrode plate between two separators instead Needless to say, even if the present invention is applied to the method and the production apparatus, the same effect can be obtained.

DESCRIPTION OF SYMBOLS 1 Secondary battery electrode sheet preparation apparatus 10 Positive electrode plate supply apparatus 20 Positive electrode plate conveyance apparatus 30 Separator supply apparatus 30U Upper stage separator supply apparatus 30L Lower stage separator supply apparatus 40 Clamping apparatus 50 Welding apparatus 60 Cutting apparatus 70 Inspection apparatus 80 No Non-defective product discharging device 90 Accumulating device 100 Electrode sheet 110 Positive electrode plate 120 (121, 122) Separator 120a Overlapping portion 120b Cutting line 120c Not completely cut portion 120e Cutting portion 120s Completely cut portion 131, 132, 135, 136 (130) Welding part 610 Cutter cylinder 611 Cylinder body 620 Cutter receiving cylinder 621 Slit 630 Support 631 Cutter base fixing part 640 Cutter base 640a Housing part 641 First base part 642 Second base part 645, 646 Carp The spring 650 sawtooth cutter 661 (660) leading side separator presser 662 (660) trailing side separator presser 670 cutter-receiving rubber 671 cutter receiving surface 691 hexagon socket head bolts

Claims (4)

A method for producing an electrode sheet used for a secondary battery having a structure in which a positive electrode plate and a negative electrode plate are laminated while being insulated from each other via a separator made of an insulating sheet,
Prepare a first separator and a second separator that are each wound in a roll shape and sent out so as to overlap each other from the state wound in the roll shape,
While the first separator and the second separator are continuously sent out, a positive electrode plate having a length in the width direction perpendicular to the separator running direction is shorter than that of the separator between these separators. Sandwiched at a predetermined interval
The positive electrode plates sandwiched between the two separators are partially welded at both sides in the width direction corresponding to the width direction of the separator and overlapping portions of the separators at a predetermined interval in the running direction of the separator. And partially welding the overlapping portion of the separators between the positive plates in the running direction of the separator at a predetermined interval in the width direction of the separator,
Cutter barrel having a structure provided with a saw blade-shaped cutter having a predetermined pitch, a separator press disposed in the front and rear of the cutter in the circumferential direction, and an urging means for supporting the separator press, and a predetermined hardness Prepare a separator cutting device consisting of a cutter receiving cylinder having a structure provided with a cutter receiver made of an elastic body,
Rotating the cutter cylinder and cutter receiving cylinder of the cutting apparatus so that the circumferential surfaces of the cutter cylinder and cutter receiving cylinder of the cutting apparatus are in the same direction as the traveling direction of the separator,
The two separators that are continuously sent out are arranged side by side at a predetermined interval in the running direction of the separator in a state where the separator is sandwiched between the separator presser of the cutter cylinder and the cutter receiver of the cutter receiver cylinder. By cutting the overlapped portion of the separator located between the positive electrode plates with a saw blade cutter having a predetermined pitch, the front and back of the positive electrode plate are sandwiched between two separators and the periphery is the overlapped portion of the separator A method for producing an electrode sheet, comprising producing an electrode sheet surrounded by   2. The electrode sheet according to claim 1, wherein a pitch of a saw portion of the saw blade cutter is 0.5 mm to 1 mm, and a difference in height between peaks and valleys is 0.4 mm to 0.9 mm. Method. An electrode sheet producing apparatus used for a secondary battery having a structure in which a positive electrode plate and a negative electrode plate are laminated while being insulated from each other via a separator made of an insulating sheet,
A separator supply device for feeding the continuous first separator and the second separator wound in a roll shape so as to overlap each other from the state wound in the roll shape;
A positive electrode plate supply device that supplies a positive electrode plate whose length in the width direction perpendicular to the separator travel direction is shorter than that of the first separator and the second separator;
A positive plate transport device for transporting the positive plate supplied by the positive plate supply device to a predetermined position;
A sandwiching device for sequentially sandwiching the positive electrode plate conveyed by the positive electrode plate conveyance device so as to be separated by a predetermined interval in the separator delivery direction between the two fed-out separators;
The positive electrode plates sandwiched between the two separators are partially welded at both sides in the width direction corresponding to the width direction of the separator and overlapping portions of the separators at a predetermined interval in the running direction of the separator. And a welding device that partially welds the overlapping portion of the separators between the positive plates in the running direction of the separator at a predetermined interval in the width direction of the separator;
A cutter body having a structure provided with a saw blade-shaped cutter having a predetermined pitch, a separator press disposed in the circumferential direction of the cutter, and an urging means for supporting the separator press, and a predetermined hardness A separator cutting device comprising a cutter receiving cylinder having a structure provided with a cutter receiver made of an elastic body having a circumferential surface of the cutter cylinder and the cutter receiving cylinder of the cutting device in the same direction as the traveling direction of the separator Equipped with a rotating cutting device,
An overlapping portion of the separators positioned between the positive electrode plates arranged side by side at a predetermined interval in the running direction of the two continuous separators that are sent out continuously is provided as a separator presser of the cutter cylinder and the cutter receiver. By cutting with a saw blade cutter having a predetermined pitch in a state where the separator is sandwiched between the barrel cutter receiver, the front and back of the positive electrode plate are sandwiched between two separators and the periphery is surrounded by the overlapping portion of the separators An electrode sheet producing apparatus for producing a prepared electrode sheet. The electrode sheet according to claim 3, wherein a pitch of the saw portion of the saw blade cutter is 0.5 mm to 1 mm, and a difference between heights of peaks and valleys is 0.4 mm to 0.9 mm. apparatus.

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