Patent Publication Number: US-2023139972-A1

Title: Laminating device, and manufacturing device for laminated electrode assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is the U.S. National Phase under 35 U.S.C. § 371 of International Patent Application No. PCT/JP2020/044533, filed on Nov. 30, 2020, which in turn claims the benefit of Japanese Patent Application No. 2020-010858, filed on Jan. 27, 2020, the entire content of each of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     Field of the Invention 
     The present disclosure relates to a laminating device, and a manufacturing device for a laminated electrode assembly. 
     Description of the Related Art 
     As in-vehicle batteries, for example, laminate-type batteries have been developed. Such a battery has a structure in which a container contains a laminated electrode assembly, in which multiple positive electrodes and multiple negative electrodes are alternatively laminated with a separator in between, and an electrolyte. 
     With regard to such a battery, Patent Literature 1 discloses a device for manufacturing a laminated electrode assembly in which a positive electrode, a negative electrode, and a separator are laminated, using, as materials, a continuous positive electrode material in which positive electrodes are continuously formed with a break line provided in between, a continuous negative electrode material in which negative electrodes are continuously formed with a break line provided in between, and a continuous separator material in which separators are continuously formed with a break line provided in between. This manufacturing device has a structure in which a continuous battery material, formed by superimposing the materials over each other, is wound around a winding drum a required number of times, and a side circumferential surface of the winding drum is partially projected in a radial direction to cut the continuous battery material at each break line. 
     Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2011-86508 
     With the abovementioned conventional manufacturing device, individual laminated electrode assemblies are manufactured by breaking the continuous battery material, wound around the drum, along the break lines. Accordingly, each time after the continuous battery material is wound a required number of times around the drum, the drum needs to be stopped before the continuous battery material is cut, so that continuous manufacturing of the laminated electrode assemblies has been difficult. Therefore, it has been difficult to speed up the manufacturing of laminated electrode assemblies. 
     SUMMARY OF THE INVENTION 
     The present disclosure has been made in view of such a situation, and a purpose thereof is to provide a technology for enabling speed-up of the manufacturing of laminated electrode assemblies. 
     One aspect of the present disclosure relates to a laminating device. The laminating device includes: multiple laminating heads that each hold a unit laminated body in which a separator and an electrode plate are laminated; a drum section that holds multiple laminating heads arranged on its circumference; a drum drive unit that rotates the drum section to advance each laminating head to a laminating position that faces a lamination stage; and multiple head drive units that move the respective laminating heads independently of the move made by the rotation of the drum section. A head drive unit for a laminating head that has reached the laminating position drives the laminating head such as to offset the advancement of the laminating head made by the rotation of the drum section. Each laminating head discharges, onto the lamination stage, a unit laminated body that the laminating head has been holding, so that multiple unit laminated bodies are laminated. 
     Another aspect of the present disclosure relates to a manufacturing device for a laminated electrode assembly. The manufacturing device includes: a first electrode cutting drum that cuts a continuous body of multiple first electrode plates into multiple first electrode plates and conveys the first electrode plates; a second electrode cutting drum that cuts a continuous body of multiple second electrode plates into multiple second electrode plates and conveys the second electrode plates; a bonding drum that laminates and bonds a first separator continuous body in which multiple first separators are continuously arranged, multiple first electrode plates supplied from the first electrode cutting drum, a second separator continuous body in which multiple second separators are continuously arranged, and multiple second electrode plates supplied from the second electrode cutting drum in this order, so as to form a continuous laminated body in which unit laminated bodies, which each are constituted by a first separator, a first electrode plate, a second separator, and a second electrode plate, are continuously arranged; a separator cutting drum that cuts the first separator continuous body and the second separator continuous body in the continuous laminated body to obtain multiple unit laminated bodies; and a laminating drum that is constituted by the laminating device according to the one aspect and that laminates multiple unit laminated bodies on a lamination stage to form a laminated electrode assembly. 
     Optional combinations of the aforementioned constituting elements, and implementation of the present disclosure in the form of methods, apparatuses, or systems may also be practiced as additional modes of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Embodiments will now be described, by way of example only, with reference to the accompanying drawings which are meant to be exemplary, not limiting, and wherein like elements are numbered alike in several Figures, in which: 
         FIG.  1    is a schematic diagram of a manufacturing device for a laminated electrode assembly according to an embodiment; 
         FIG.  2    is a sectional view that schematically illustrates part of a laminating device according to the embodiment; 
         FIG.  3    is a perspective view of the laminating device according to the embodiment; 
         FIG.  4 A  is an operation waveform diagram of a drum drive unit,  FIG.  4 B  is an operation waveform diagram of a head drive unit, and  FIG.  4 C  is an operation waveform diagram of a laminating head; and 
         FIGS.  5 A- 5 L  are schematic diagrams that each illustrate moving states of laminating heads. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the following, the present disclosure will be described based on a preferred embodiment with reference to the drawings. The embodiment is intended to be illustrative only and not to limit the present disclosure, so that it should be understood that not all of the features or combinations thereof described in the embodiment are necessarily essential to the present disclosure. Like reference characters denote like or corresponding constituting elements, members, and processes in each drawing, and repetitive description will be omitted as appropriate. 
     Also, the scale or shape of each component shown in each drawing is defined for the sake of convenience to facilitate the explanation and is not to be regarded as limitative unless otherwise specified. Further, when the terms “first”, “second”, and the like are used in the present specification or claims, such terms do not imply any order or degree of importance and are used to distinguish one configuration from another, unless otherwise specified. Further, in each drawing, part of members less important in describing the embodiment may be omitted. 
       FIG.  1    is a schematic diagram of a manufacturing device for a laminated electrode assembly according to an embodiment. A manufacturing device  1  for a laminated electrode assembly is a continuous drum-type manufacturing device in which multiple drums are combined. Performing each process of cutting, heating, bonding, laminating, and the like of electrode bodies and separators on the drums enables high-speed and continuous manufacturing of laminated electrode assemblies. The laminated electrode assemblies may be used, for example, for lithium-ion secondary batteries. 
     The manufacturing device  1  includes a first electrode cutting drum  2 , a first electrode heating drum  4 , a second electrode cutting drum  6 , a second electrode heating drum  8 , a bonding drum  10 , a separator cutting drum  12 , and a laminating drum  14 . 
     The first electrode cutting drum  2  cuts a continuous body of multiple first electrode plates into multiple individual first electrode plates and conveys the plates. The first electrode cutting drum  2  has a first radius and rotates at a first angular velocity around the central axis. In the present embodiment, the first electrode is a negative electrode. To the first electrode cutting drum  2 , a strip-shaped first electrode continuous body N as the continuous body of multiple first electrode plates is supplied. The first electrode continuous body N includes a first electrode current collector and a first electrode active material layer. The first electrode active material layer is laminated on the first electrode current collector. In the present embodiment, the first electrode active material layer is laminated on the both sides of the first electrode current collector, but the first electrode active material layer may be laminated on only one side of the first electrode current collector. 
     Each of the first electrode current collector and the first electrode active material layer can be made of a publicly-known material and has a publicly-known structure. The first electrode current collector may be, for example, constituted by foil or a porous body made of copper, aluminum, or the like. The first electrode active material layer may be formed by applying, onto a surface of the first electrode current collector, first electrode mixture slurry containing a first electrode active material, a binder, a dispersant, and the like and by drying and rolling the applied film. The thickness of the first electrode current collector may be in the range from 3 μm to 50 μm inclusive, for example. Also, the thickness of the first electrode active material layer may be in the range from 10 μm to 100 μm inclusive, for example. 
     The first electrode cutting drum  2  includes multiple holding heads arranged in a circumferential direction of the drum, and a cutting blade that cuts the first electrode continuous body N into multiple individual first electrode plates. Each of the multiple holding heads includes a holding surface that adsorbs and holds the first electrode continuous body N. The holding surface of each holding head faces outward from the first electrode cutting drum  2 . The first electrode continuous body N supplied to the first electrode cutting drum  2  is conveyed by the rotation of the first electrode cutting drum  2  while being adsorbed and held by the holding surfaces of the multiple holding heads. 
     Each of the multiple holding heads rotates around the central axis of the first electrode cutting drum  2  and can also move in a circumferential direction of the drum independently of other holding heads. Relative movement of each holding head is achieved by mounting thereon a motor that is different from the motor used to rotate the first electrode cutting drum  2 . For example, if two holding heads adjacent to each other in a circumferential direction are assumed to be a first holding head and a second holding head, the first and second holding heads rotate around the central axis of the first electrode cutting drum  2  at a constant speed by means of the rotation of the first electrode cutting drum  2 . Also, by the driving of the motor of each holding head, the relative speed of the two holding heads can be changed in a certain section on the circumference of the drum. 
     For example, at one timing, both the first and second holding heads rotate at a constant speed and have a relative speed of zero; at another timing, the first holding head increases its speed in a direction away from the subsequent second holding head, so that the holding heads have a finite relative speed. Such independent driving of the holding heads enables adjustment of the positions of cutting by the cutting blade in the first electrode continuous body N and also enables adjustment of the positions of the individually divided first electrode plates, for example. When each holding head should be rotated at a constant speed around the central axis of the first electrode cutting drum  2 , to the movement of each holding head made by the rotation of the first electrode cutting drum  2 , constant speed movement of each holding head made by the driving of the motor of each holding head may be added. 
     The first electrode cutting drum  2  adsorbs and holds the supplied first electrode continuous body N and rotates to convey the first electrode continuous body N. At a cutting position  16  schematically illustrated in  FIG.  1   , the first electrode cutting drum  2  cuts the first electrode continuous body N to produce the first electrode plates. The first electrode continuous body N is cut by the cutting blade at a position between adjacent holding heads, so that multiple individual first electrode plates are obtained. Each first electrode plate thus obtained is conveyed while being adsorbed and held by each holding head. The first electrode cutting drum  2  may include various cameras. Such cameras can monitor the positions of the multiple produced first electrode plates. As an example, the position of the first electrode continuous body N before the cutting is monitored at a conveying roller located on the upstream side of the first electrode cutting drum  2 . The first electrode cutting drum  2  may also include a sensor besides cameras to monitor the position of a holding head or the like. 
     The first electrode heating drum  4  is disposed in close proximity to the first electrode cutting drum  2 . The first electrode heating drum  4  has a second radius and rotates at a second angular velocity around the central axis. The second radius of the first electrode heating drum  4  may be the same as or different from the first radius of the first electrode cutting drum  2 . Meanwhile, the second angular velocity of the first electrode heating drum  4  is different from the first angular velocity of the first electrode cutting drum  2 . Also, the second angular velocity of the first electrode heating drum  4  is set so that the linear velocity thereof is substantially identical with the linear velocity of the bonding drum  10 , which will be described later. 
     As an example, the second radius may be identical with the first radius, and the second angular velocity may be set higher than the first angular velocity. In this case, the linear velocity of the first electrode heating drum  4  is larger than the linear velocity of the first electrode cutting drum  2 . Therefore, before the proximity position between the first electrode cutting drum  2  and the first electrode heating drum  4 , the speed of a holding head of the first electrode cutting drum  2  is temporarily increased until it becomes substantially identical with the linear velocity of the first electrode heating drum  4 . As a result, the relative speed of the holding head with respect to the first electrode heating drum  4  becomes substantially zero. At the timing when the relative speed becomes substantially zero, the holding head discharges, to the first electrode heating drum  4  side, the first electrode plate that the holding head has adsorbed and held. After the discharge of the first electrode plate, the speed of the holding head returns to the speed before the increase of speed. 
     The first electrode heating drum  4  rotates while adsorbing and holding the first electrode plates discharged from the first electrode cutting drum  2  and preheats the first electrode plates with a built-in heater. The preheating is performed to thermally bond a first electrode plate and a separator in the subsequent bonding process. Although the first electrode plates are heated at a heating position  18  in the present embodiment, the position is not limited thereto. For example, the first electrode plates may be heated in the entire circumferential area of the first electrode heating drum  4 . 
     The second electrode cutting drum  6  cuts a continuous body of multiple second electrode plates into multiple individual second electrode plates and conveys the plates. The second electrode cutting drum  6  has a third radius and rotates at a third angular velocity around the central axis. In the present embodiment, the second electrode is a positive electrode. To the second electrode cutting drum  6 , a strip-shaped second electrode continuous body P as the continuous body of multiple second electrode plates is supplied. The second electrode continuous body P includes a second electrode current collector and a second electrode active material layer. The second electrode active material layer is laminated on the second electrode current collector. In the present embodiment, the second electrode active material layer is laminated on the both sides of the second electrode current collector, but the second electrode active material layer may be laminated on only one side of the second electrode current collector. 
     Each of the second electrode current collector and the second electrode active material layer can be made of a publicly-known material and has a publicly-known structure. The second electrode current collector may be, for example, constituted by foil or a porous body made of stainless steel, aluminum, or the like. The second electrode active material layer may be formed by applying, onto a surface of the second electrode current collector, second electrode mixture slurry containing a second electrode active material, a binder, a dispersant, and the like and by drying and rolling the applied film. The thickness of the second electrode current collector may be in the range from 3 μm to 50 μm inclusive, for example. Also, the thickness of the second electrode active material layer may be in the range from 10 μm to 100 μm inclusive, for example. 
     The second electrode cutting drum  6  includes multiple holding heads arranged in a circumferential direction of the drum, and a cutting blade that cuts the second electrode continuous body P into multiple individual second electrode plates. Each of the multiple holding heads includes a holding surface that adsorbs and holds the second electrode continuous body P. The holding surface of each holding head faces outward from the second electrode cutting drum  6 . The second electrode continuous body P supplied to the second electrode cutting drum  6  is conveyed by the rotation of the second electrode cutting drum  6  while being adsorbed and held by the holding surfaces of the multiple holding heads. 
     Each of the multiple holding heads rotates around the central axis of the second electrode cutting drum  6  and can also move in a circumferential direction of the drum independently of other holding heads. Relative movement of each holding head is achieved by mounting thereon a motor that is different from the motor used to rotate the second electrode cutting drum  6 . For example, a first holding head and a second holding head adjacent to each other in a circumferential direction rotate around the central axis of the second electrode cutting drum  6  at a constant speed by means of the rotation of the second electrode cutting drum  6 . Also, by the driving of the motor of each holding head, the relative speed of the two holding heads can be changed in a certain section on the circumference of the drum. The change in the relative speed of the first and second holding heads and the combination of the rotation of the second electrode cutting drum  6  and the driving of the motors provided in the holding heads are the same as those in the case of the first electrode cutting drum  2 . 
     The second electrode cutting drum  6  adsorbs and holds the supplied second electrode continuous body P and rotates to convey the second electrode continuous body P. At a cutting position  20  schematically illustrated in  FIG.  1   , the second electrode cutting drum  6  cuts the second electrode continuous body P to produce the second electrode plates. The second electrode continuous body P is cut by the cutting blade at a position between adjacent holding heads, so that multiple individual second electrode plates are obtained. Each second electrode plate thus obtained is conveyed while being adsorbed and held by each holding head. The second electrode cutting drum  6  may include various cameras. Such cameras can monitor the positions of the multiple produced second electrode plates. As an example, the position of the second electrode continuous body P before the cutting is monitored at a conveying roller located on the upstream side of the second electrode cutting drum  6 . The second electrode cutting drum  6  may also include a sensor besides cameras to monitor the position of a holding head or the like. 
     The second electrode heating drum  8  is disposed in close proximity to the second electrode cutting drum  6 . The second electrode heating drum  8  has a fourth radius and rotates at a fourth angular velocity around the central axis. The fourth radius of the second electrode heating drum  8  may be the same as or different from the third radius of the second electrode cutting drum  6 . Meanwhile, the fourth angular velocity of the second electrode heating drum  8  is different from the third angular velocity of the second electrode cutting drum  6 . Also, the fourth angular velocity of the second electrode heating drum  8  is set so that the linear velocity thereof is substantially identical with the linear velocity of the bonding drum  10 . 
     As an example, the fourth radius may be identical with the third radius, and the fourth angular velocity may be set higher than the third angular velocity. In this case, the linear velocity of the second electrode heating drum  8  is larger than the linear velocity of the second electrode cutting drum  6 . Therefore, before the proximity position between the second electrode cutting drum  6  and the second electrode heating drum  8 , the speed of a holding head of the second electrode cutting drum  6  is temporarily increased until it becomes substantially identical with the linear velocity of the second electrode heating drum  8 . As a result, the relative speed of the holding head with respect to the second electrode heating drum  8  becomes substantially zero. At the timing when the relative speed becomes substantially zero, the holding head discharges, to the second electrode heating drum  8  side, the second electrode plate that the holding head has adsorbed and held. After the discharge of the second electrode plate, the speed of the holding head returns to the speed before the increase of speed. 
     The second electrode heating drum  8  rotates while adsorbing and holding the second electrode plates discharged from the second electrode cutting drum  6  and preheats the second electrode plates with a built-in heater. The preheating is performed to thermally bond a second electrode plate and a separator in the subsequent bonding process. Although the second electrode plates are heated at a heating position  22  in the present embodiment, the position is not limited thereto. For example, the second electrode plates may be heated in the entire circumferential area of the second electrode heating drum  8 . 
     The bonding drum  10  forms a continuous laminated body in which unit laminated bodies, which each are constituted by a first separator, a first electrode plate, a second separator, and a second electrode plate, are continuously arranged. The bonding drum  10  is disposed in close proximity to the first electrode heating drum  4  and the second electrode heating drum  8 . The bonding drum  10  has a fifth radius and rotates at a fifth angular velocity around the central axis. To the bonding drum  10 , a strip-shaped first separator continuous body S 1 , in which multiple first separators are continuously arranged, and a strip-shaped second separator continuous body S 2 , in which multiple second separators are continuously arranged, are supplied. On a surface of each of the first separator continuous body S 1  and the second separator continuous body S 2 , a thermal bonding layer is provided. The thermal bonding layer has a property of developing no adhesiveness at room temperature but developing adhesiveness when heated. The thermal bonding layer may be, for example, a thermoplastic layer containing a thermoplastic polymer, which develops adhesiveness based on plastic deformation of the thermoplastic polymer caused by heating. 
     Also, to the bonding drum  10 , multiple first electrode plates are supplied from the first electrode cutting drum  2  via the first electrode heating drum  4 , and multiple second electrode plates are supplied from the second electrode cutting drum  6  via the second electrode heating drum  8 . A first electrode plate is rotationally conveyed while being preheated on the first electrode heating drum  4  and is discharged, to the bonding drum  10  side, at the proximity position between the first electrode heating drum  4  and the bonding drum  10 . A second electrode plate is rotationally conveyed while being preheated on the second electrode heating drum  8  and is discharged, to the bonding drum  10  side, at the proximity position between the second electrode heating drum  8  and the bonding drum  10 . 
     The first separator continuous body S 1 , each first electrode plate, the second separator continuous body S 2 , and each second electrode plate are supplied to the bonding drum  10  at positions provided in the enumerated order from the upstream side of the rotational direction of the bonding drum  10 . Accordingly, the first separator continuous body S 1  is supplied to the bonding drum  10  first at a certain position. The first separator continuous body S 1  is adsorbed and held by the bonding drum  10  and rotationally conveyed. Subsequently, at a position on the downstream side of the supply position of the first separator continuous body S 1 , the first electrode plates are supplied from the first electrode heating drum  4  to the bonding drum  10  and placed on the first separator continuous body S 1 . The multiple first electrode plates are arranged on the first separator continuous body S 1  at predetermined intervals in the conveying direction of the first separator continuous body S 1 . 
     Subsequently, at a position on the downstream side of the supply position of the first electrode plates, the second separator continuous body S 2  is supplied to the bonding drum  10  and placed over the multiple first electrode plates. Thereafter, the first separator continuous body S 1 , multiple first electrode plates, and second separator continuous body S 2  are pressurized by a thermocompression bonding roller  24 , at a position on the downstream side of the supply position of the second separator continuous body S 2 . Accordingly, the first separator continuous body S 1 , each first electrode plate, and the second separator continuous body S 2  are bonded together. Subsequently, at a position on the downstream side of the position of pressure bonding by the thermocompression bonding roller  24 , the second electrode plates are supplied from the second electrode heating drum  8  to the bonding drum  10  and placed on the second separator continuous body S 2 . The multiple second electrode plates are arranged on the second separator continuous body S 2  at predetermined intervals in the conveying direction of the second separator continuous body S 2 . Also, the multiple second electrode plates are bonded to the second separator continuous body S 2  by the pressing force of the second electrode heating drum  8 . 
     Through the process described above, the first separator continuous body S 1 , multiple first electrode plates, second separator continuous body S 2 , and multiple second electrode plates are laminated in this order and bonded to each other, forming a continuous laminated body  26 . The continuous laminated body  26  has a structure in which the unit laminated bodies, which each are constituted by a first separator, a first electrode plate, a second separator, and a second electrode plate, are continuously connected by the first separator continuous body S 1  and the second separator continuous body S 2 . The continuous laminated body  26  is conveyed from the bonding drum  10  to the separator cutting drum  12 . By halting the supply of the second electrode plates from the second electrode cutting drum  6  side, three-layered unit laminated bodies without the second electrode plates may be produced after every fixed number of pieces. The electrode plates of which supply is halted may also be the first electrode plates. 
     The separator cutting drum  12  cuts the first separator continuous body S 1  and the second separator continuous body S 2  in the continuous laminated body  26  to obtain multiple individual unit laminated bodies. The separator cutting drum  12  has a sixth radius and rotates at a sixth angular velocity around the central axis. The separator cutting drum  12  includes multiple holding heads arranged in a circumferential direction of the drum, and a cutting blade that cuts the continuous laminated body  26  into multiple individual unit laminated bodies. Each of the multiple holding heads includes a holding surface that adsorbs and holds the continuous laminated body  26 . The holding surface of each holding head faces outward from the separator cutting drum  12 . The continuous laminated body  26  supplied to the separator cutting drum  12  is conveyed by the rotation of the separator cutting drum  12  while being adsorbed and held by the holding surfaces of the multiple holding heads. 
     Each of the multiple holding heads rotates around the central axis of the separator cutting drum  12  and may also be capable of moving in a circumferential direction of the drum independently of other holding heads. Relative movement of each holding head is achieved by mounting thereon a motor that is different from the motor used to rotate the separator cutting drum  12 . For example, a first holding head and a second holding head adjacent to each other in a circumferential direction rotate around the central axis of the separator cutting drum  12  at a constant speed by means of the rotation of the separator cutting drum  12 . Also, by the driving of the motor of each holding head, the relative speed of the two holding heads can be changed in a certain section on the circumference of the drum. The change in the relative speed of the first and second holding heads and the combination of the rotation of the separator cutting drum  12  and the driving of the motors provided in the holding heads are the same as those in the case of the first electrode cutting drum  2 . 
     The separator cutting drum  12  adsorbs and holds the supplied continuous laminated body  26  and rotates to convey the continuous laminated body  26 . At a cutting position  28  schematically illustrated in  FIG.  1   , the separator cutting drum  12  cuts the continuous laminated body  26  to produce the unit laminated bodies. The continuous laminated body  26  is cut by the cutting blade at a position between adjacent holding heads, so that multiple individual unit laminated bodies are obtained. At the time, in the continuous laminated body  26 , the first separator continuous body S 1  and the second separator continuous body S 2  are cut at a position between electrode plates that are adjacent in the conveying direction of the continuous laminated body  26 . Each unit laminated body thus obtained is conveyed while being adsorbed and held by each holding head. A holding head discharges, to the laminating drum  14  side, a unit laminated body that the holding head has adsorbed and held. The separator cutting drum  12  may include various cameras. Such cameras can monitor the positions of the multiple produced unit laminated bodies. As an example, the position of the continuous laminated body  26  before the cutting is monitored at a conveying roller located on the upstream side of the separator cutting drum  12 . The separator cutting drum  12  may also include a sensor besides cameras to monitor the position of a holding head or the like. 
     The laminating drum  14  laminates multiple unit laminated bodies on a lamination stage  30  to form a laminated electrode assembly. The laminating drum  14  has a seventh radius and rotates at a seventh angular velocity around the central axis. The laminating drum  14  includes multiple laminating heads arranged in a circumferential direction of the drum. Each laminating head includes a holding surface that adsorbs and holds a unit laminated body. The holding surface of each laminating head faces outward from the laminating drum  14 . Each of the multiple laminating heads rotates around the central axis of the laminating drum  14  and can also move in a circumferential direction of the drum independently of other laminating heads. Relative movement of each laminating head is achieved by mounting thereon a motor that is different from the motor used to rotate the laminating drum  14 , as will be described later. Upon reaching a laminating position that faces the lamination stage  30 , each laminating head  106  discharges, to the lamination stage  30  side, a unit laminated body that the laminating head  106  has been holding. 
     The lamination stage  30  is disposed immediately beneath the laminating drum  14 . On the lamination stage  30 , the unit laminated bodies discharged from the laminating drum  14  are sequentially laminated. Thus, a laminated electrode assembly is formed. The lamination stage  30  can be driven in an X-axis direction and a Y-axis direction perpendicular to each other. Also, a tilt angle on an X-Y plane of the lamination stage  30  can be adjusted. This enables adjustment of the positions in the X-axis direction and the Y-axis direction and the tilt angle of a unit laminated body discharged from the laminating drum  14 , with respect to a unit laminated body already laminated on the lamination stage  30 . The lamination stage  30  includes clicks at the four corners, and the multiple unit laminated bodies laminated on the lamination stage  30  are pressed and fixed by the clicks. Also, the multiple unit laminated bodies thus laminated are pressurized and/or heated to be bonded to each other. 
     The laminating drum  14  is constituted by a laminating device  100  according to the present embodiment described below.  FIG.  2    is a sectional view that schematically illustrates part of the laminating device  100  according to the embodiment.  FIG.  3    is a perspective view of the laminating device  100  according to the embodiment.  FIG.  2    illustrates half of a cross section of the laminating device  100 .  FIG.  3    illustrates the laminating device  100  observed from the direction of arrow A in  FIG.  2   . 
     The laminating device  100  constituting the laminating drum  14  includes a drum section  102 , a drum drive unit  104 , multiple laminating heads  106 , and multiple head drive units  108 . The drum section  102  holds the multiple laminating heads  106  arranged on its circumference. The drum drive unit  104  rotates the drum section  102  to advance each laminating head  106  to a laminating position facing the lamination stage  30 . The head drive units  108  move the respective laminating heads  106  independently of the move thereof made by the rotation of the drum section  102 . 
     The drum section  102  includes a rotating shaft  110 , a large gear  112 , and a flange portion  114 . The drum drive unit  104  includes a motor  116  and a shaft base  118 . The rotating shaft  110  may be of cylindrical shape, for example, and is connected at one end to the motor  116  via the shaft base  118 . For the motor  116 , a publicly-known motor may be used. The rotating shaft  110  rotates by means of the driving of the motor  116 . The rotating shaft  110  corresponds to the central axis of the laminating drum  14 . The large gear  112  is fixed to the rotating shaft  110 . The large gear  112  of the present embodiment is fixed to an outer circumferential surface of the rotating shaft  110 . Also, the large gear  112  is provided over the entire circumference of the rotating shaft  110 . The flange portion  114  projects perpendicularly to an axial direction of the rotating shaft  110 . The flange portion  114  is discoid and provided over the entire circumference of the rotating shaft  110 . On a circumferential edge part of the flange portion  114 , an arc guide  120  is provided. 
     The multiple head drive units  108  are arranged in a circumferential direction of the flange portion  114 . Each head drive unit  108  includes a bracket  122 , a motor  124 , and a small gear  126 . The bracket  122  has a substantial U-shape in cross section, and the both sides of the substantial U-shape sandwich an edge of the flange portion  114  via the arc guide  120 . The motor  124  is supported by the bracket  122 . For the motor  124 , a publicly-known motor may be used. The small gear  126  is connected to the rotating shaft of the motor  124  and rotates by means of the driving of the motor  124 . The small gear  126  meshes with the large gear  112  fixed to the rotating shaft  110  side. When the motor  124  is driven, the drive torque is transmitted to the large gear  112  that meshes with the small gear  126 . This allows each head drive unit  108  to move independently on the circumference of the flange portion  114  along the arc guide  120 . 
     The multiple laminating heads  106  are supported respectively by the head drive units  108 . Accordingly, the multiple laminating heads  106  are arranged in a circumferential direction of the flange portion  114 . When the rotating shaft  110  rotates, the rotary torque is transmitted to the small gear  126  that meshes with the large gear  112 . Accordingly, each laminating head  106  rotates around the rotating shaft  110 . Also, each laminating head  106  can move by means of a head drive unit  108 , besides the move made by the rotation of the drum section  102 . 
     For example, a first laminating head and a second laminating head adjacent to each other in a circumferential direction of the drum section  102  rotate around the central axis of the drum section  102  at a constant speed, by means of the rotation of the drum section  102 . Also, the relative speed of those laminating heads can be changed in a certain section on the circumference of the drum section  102 . For example, at one timing, both the first and second laminating heads rotate at a constant speed and have a relative speed of zero; at another timing, the first laminating head increases its speed in a direction away from the subsequent second laminating head, so that the laminating heads have a finite relative speed. When each laminating head  106  should be rotated at a constant speed around the central axis of the drum section  102 , to the movement of each laminating head  106  made by the rotation of the drum section  102 , constant speed movement of each laminating head  106  made by the driving of a corresponding head drive unit  108  may be added. The operation of each drive unit will be detailed later. 
     Each laminating head  106  includes a holding surface  128  that faces outward from the circumference of the drum section  102 . Each holding surface  128  is positioned at a distance of the seventh radius from the center of the drum section  102 . On each holding surface  128 , an adsorption hole (not illustrated) is provided to adsorb and hold a unit laminated body W. Since air is sucked through the adsorption hole, the unit laminated body W is adsorbed and held by the suction force. The unit laminated body W has a structure in which separators and electrode plates are laminated. The unit laminated body W in the present embodiment is constituted by a first separator, a first electrode plate, a second separator, and a second electrode plate, as described previously. While being adsorbed and held by the holding surface  128  of each laminating head  106 , each unit laminated body W is conveyed by the rotation of the drum section  102  or by the move of a corresponding head drive unit  108 . 
     The operation of the drum drive unit  104  and the head drive units  108  is controlled by a control device  130 . The control device  130  may be implemented by an element such as a CPU or memory of a computer or by a circuit as a hardware configuration, and by a computer program or the like as a software configuration.  FIG.  2    illustrates a functional block implemented by cooperation of such components. It will be naturally understood by those skilled in the art that the functional block may be implemented in a variety of forms by combinations of hardware and software. 
     The control device  130  receives image data from a camera that images the laminating drum  14  and, based on the position of each laminating head  106  and the like derived from the image data, the control device  130  can control the operation of each part. The control device  130  may also acquire information from a sensor other than the camera to control the operation of each part. Also, each part of the laminating device  100  may be able to operate based on a preset operation program. 
     In the lamination process of each unit laminated body W, the operation of each part is controlled as follows.  FIG.  4 A  is an operation waveform diagram of the drum drive unit  104 .  FIG.  4 B  is an operation waveform diagram of a head drive unit  108 .  FIG.  4 C  is an operation waveform diagram of a laminating head  106 . In each of  FIGS.  4 A- 4 C , the horizontal axis represents time (relative values), and the vertical axis represents speed.  FIGS.  5 A- 5 L  are schematic diagrams that each illustrate moving states of laminating heads  106 .  FIGS.  5 A- 5 L  focus on the movement of a certain laminating head  106   a.  Time passes in the order of  FIGS.  5 A to  5 L , and the time interval between two consecutive figures is equal. 
       FIGS.  5 A- 5 D  show the states of the laminating head  106   a  during time t 2  in  FIGS.  4 B and  4 C .  FIGS.  5 E- 5 H  show the states of the laminating head  106   a  during time t 3  in  FIGS.  4 B and  4 C .  FIGS.  5 I- 5 L  show the states of the laminating head  106   a  during time t 4  in  FIGS.  4 B and  4 C . 
     The drum drive unit  104  is driven as shown by the operation waveform in  FIG.  4 A , so that the drum section  102  continuously rotates at a constant speed. Also, as shown in  FIG.  4 B , a head drive unit  108  repeats constant speed driving in the same direction as the rotating direction of the rotating shaft  110  (forward direction) during time t 1 . Accordingly, as shown in  FIG.  4 C , the laminating head  106   a  is conveyed at a constant speed during time t 1  by means of the rotation of the drum section  102  and the move of the drum drive unit  104 , so as to get closer to the lamination stage  30 . Also, during time t 1 , the linear velocity of the laminating head  106   a  becomes substantially identical with the linear velocity of the separator cutting drum  12 , and a unit laminated body W discharged from the separator cutting drum  12  is adsorbed by a laminating head  106 . 
     When the laminating head  106   a  gets closer to the lamination stage  30  and reaches a position at a certain distance from the lamination stage  30 , the corresponding head drive unit  108  accelerates the movement of the laminating head  106   a  in the rotating direction of the drum section  102 . More specifically, as shown in  FIGS.  4 B and  4 C , the head drive unit  108  increases the output during time t 2  to accelerate the laminating head  106   a  and bring the laminating head  106   a  closer to the lamination stage  30 . This widens the distance between the laminating head  106   a  and the subsequent laminating head  106   b,  as shown in  FIGS.  5 A- 5 D . As a result, the time for which the laminating head  106   a  is stopped at the laminating position can be spared. 
     When the laminating head  106   a  has reached the laminating position, the corresponding head drive unit  108  drives the laminating head  106   a  such as to offset the advancement of the laminating head  106   a  made by the rotation of the drum section  102 . More specifically, as shown in  FIG.  4 B , the head drive unit  108  makes advancement in the opposite direction to the rotating direction of the drum section  102  during time t 3 . In other words, the head drive unit  108  rotates the motor  124  in the opposite direction. Thus, the direction of the movement of the laminating head  106   a  made by the head drive unit  108  is opposite to the direction of the movement of the laminating head  106   a  made by the drum drive unit  104 , so that the moving speed of the laminating head  106   a  becomes zero, as shown in  FIG.  4 C . As a result, the laminating head  106   a  stops at the laminating position, as shown in  FIGS.  5 E- 5 H . 
     While stopping at the laminating position, the laminating head  106   a  discharges, onto the lamination stage  30 , the unit laminated body W that the laminating head  106   a  has been holding. The laminating head  106  advances toward the lamination stage  30  at the laminating position, and, after discharging the unit laminated body W onto the lamination stage  30 , the laminating head  106  recedes from the lamination stage  30 . Since the unit laminated body W is discharged onto the lamination stage  30  while the movement of the laminating head  106  in a circumferential direction of the drum section  102  is stopped, the unit laminated body W can be discharged onto the lamination stage  30  with high positional accuracy. 
     After the laminating head  106   a  has discharged the unit laminated body W, the corresponding head drive unit  108  accelerates the movement of the laminating head  106   a  in the rotating direction of the drum section  102 . More specifically, as shown in  FIGS.  4 B and  4 C , the head drive unit  108  increases the output during time t 4  to accelerate the laminating head  106   a  and displace the laminating head  106   a  from the lamination stage  30 . This allows the subsequent laminating head  106   b  to advance to the laminating position while accelerating, as shown in  FIGS.  5 I- 5 L . The output of the head drive unit  108  during time t 4  is set larger than the output of the head drive unit  108  during time t 1 . 
     Also, while the dimensional design is provided such that the circumference of the drum section  102  is divided into 16 so that 16 laminating heads  106  are mounted on the drum section  102 , for example, 12 laminating heads  106  are mounted on the laminating device  100  of the present embodiment. Thus, by reducing the number of laminating heads  106  arranged on the circumference of the drum section  102  below the maximum number of laminating heads  106  that can be placed in design, the space between adjacent laminating heads  106  can be widened. This can expand the area where an arbitrary laminating head  106  can be accelerated or decelerated relative to an adjacent laminating head  106 . Therefore, when a laminating head  106  is accelerated or decelerated before or after the laminating position, the change of speed can be made gradual. 
     As described above, the laminating device  100  according to the present embodiment includes: multiple laminating heads  106  that each hold a unit laminated body W in which a separator and an electrode plate are laminated; a drum section  102  that holds multiple laminating heads  106  arranged on its circumference; a drum drive unit  104  that rotates the drum section  102  to advance each laminating head  106  to a laminating position that faces a lamination stage  30 ; and multiple head drive units  108  that move the respective laminating heads  106  independently of the move made by the rotation of the drum section  102 . A head drive unit  108  for a laminating head  106  that has reached the laminating position drives the laminating head  106  such as to offset the advancement of the laminating head  106  made by the rotation of the drum section  102 . Each laminating head  106  discharges, onto the lamination stage  30 , a unit laminated body W that the laminating head  106  has been holding, so that multiple unit laminated bodies W are laminated. 
     More specifically, the laminating device  100  includes the drum drive unit  104  that repeatedly outputs a predetermined operation waveform, the multiple laminating heads  106  that are arranged in a circumferential direction of the drum section  102  (main shaft) rotated by the drum drive unit  104  and that respectively hold unit laminated bodies W, and the head drive units  108  that respectively allow the multiple laminating heads  106  to move independently. In the laminating device  100 , the operation waveforms of the drum drive unit  104  and a head drive unit  108  are combined, so that the operation waveform of the corresponding laminating head  106  is obtained. At the laminating position, the head drive unit  108  operates to offset the move of the corresponding laminating head  106  made by the drum drive unit  104 , so as to adjust the speed of the laminating head  106  to zero. 
     Thus, by combining the rotation of the drum section  102  and the movement of a head drive unit  108  to stop the corresponding laminating head  106  at the laminating position, a unit laminated body W can be locally stopped at the laminating position to be laminated on the lamination stage  30 , without stopping the conveyance of the unit laminated bodies W in the area excluding the laminating position. Accordingly, the speed of manufacturing of the laminated electrode assemblies can be increased. Also, since the unit laminated bodies W can be laminated on the lamination stage  30  with high positional accuracy, laminated electrode assemblies of higher quality can be formed. 
     As a method for stopping a laminating head  106 , for example, providing a cam mechanism on a circumferential edge part of the flange portion  114  may be conceivable. However, when a laminating head  106  is stopped using a cam mechanism, a large impact may be applied to the laminating head  106  at the time of stop. In this case, vibration will remain, which will make lamination with high positional accuracy difficult. Also, waiting for the vibration to subside will reduce the speed of manufacturing of the laminated electrode assemblies. Further, in order to withstand the impact that occurs when the laminating head  106  is stopped, each part needs to have higher rigidity. In particular, to further speed up the manufacturing of the laminated electrode assemblies, the speed of the movement of the laminating head  106  made by the rotation of the drum section  102  will be increased, and the impact at the time when the laminating head  106  is stopped will become greater. Therefore, the required rigidity will also become higher. Also, if such a cam mechanism is provided, the structure will become complicated, and the number of necessary parts will increase. 
     In contrast, by allowing a laminating head  106  to move in the opposite direction by means of the corresponding head drive unit  108  to offset the move of the laminating head  106  made by the rotation of the drum section  102 , the impact that occurs when the laminating head  106  is stopped at the laminating position can be suppressed. Therefore, the manufacturing of laminated electrode assemblies can be sped up while the manufacturing equipment is made simplified. 
     Also, a head drive unit  108  accelerates, when the corresponding laminating head  106  gets closer to the lamination stage  30  and reaches a position at a predetermined distance from the lamination stage  30 , the movement of the corresponding laminating head  106  in the rotating direction of the drum section  102 . Accordingly, the time for which the laminating head  106  is stopped at the laminating position can be spared, so that the speed of manufacturing of the laminated electrode assemblies can be further increased. Also, the quality of the laminated electrode assemblies can be further improved. 
     Also, a head drive unit  108  accelerates, after the corresponding laminating head  106  discharges a unit laminated body W, the movement of the corresponding laminating head  106  in the rotating direction of the drum section  102 . This can allow the subsequent laminating head  106  to advance to the laminating position more smoothly. Therefore, the speed of manufacturing of the laminated electrode assemblies can be further increased. 
     The manufacturing device  1  for a laminated electrode assembly according to the present embodiment includes: the first electrode cutting drum  2  that cuts a continuous body of multiple first electrode plates into multiple first electrode plates and conveys the first electrode plates; the second electrode cutting drum  6  that cuts a continuous body of multiple second electrode plates into multiple second electrode plates and conveys the second electrode plates; the bonding drum  10  that laminates and bonds the first separator continuous body S 1  in which multiple first separators are continuously arranged, multiple first electrode plates supplied from the first electrode cutting drum  2 , the second separator continuous body S 2  in which multiple second separators are continuously arranged, and multiple second electrode plates supplied from the second electrode cutting drum  6  in this order, so as to form a continuous laminated body  26  in which unit laminated bodies W, which each are constituted by a first separator, a first electrode plate, a second separator, and a second electrode plate, are continuously arranged; the separator cutting drum  12  that cuts the first separator continuous body S 1  and the second separator continuous body S 2  in the continuous laminated body  26  to obtain multiple unit laminated bodies W; and the laminating drum  14  that is constituted by the laminating device  100  according to the present embodiment and that laminates multiple unit laminated bodies W on the lamination stage  30  to form a laminated electrode assembly. This enables both the quality improvement and the throughput improvement of the laminated electrode assemblies and thus the batteries. 
     An embodiment of the present disclosure has been described in detail. The abovementioned embodiment merely describes a specific example for carrying out the present disclosure. The embodiment is not intended to limit the technical scope of the present disclosure, and various design modifications, including changes, addition, and deletion of constituting elements, may be made to the embodiment without departing from the scope of ideas of the present disclosure defined in the claims. Such an additional embodiment with a design modification added has the effect of each of the combined embodiments and modifications. In the aforementioned embodiment, matters to which design modifications may be made are emphasized with the expression of “of the present embodiment”, “in the present embodiment”, or the like. However, design modifications may also be made to matters without such expression. Optional combinations of the abovementioned constituting elements may also be employed as additional modes of the present disclosure. Also, the hatching provided on the cross sections in the drawings does not limit the materials of the objects with the hatching.