阅读说明：本技术 二次电池用层叠体的制造装置和制造方法 (Apparatus and method for manufacturing secondary battery laminate ) 是由 大西和幸 大森弘士 于 2019-03-20 设计创作，主要内容包括：本发明提供一种能够连续且高效地制造层叠型二次电池的、具有间隔件和电极的二次电池用层叠体的高效的制造技术。本发明的二次电池用层叠体的制造装置具有：电极卷,其将长条的电极卷料卷成卷状而成；间隔件卷,其将长条的间隔件卷料卷成卷状而成；贴合机构,其将从间隔件卷放出的间隔件卷料和从电极卷放出的电极卷料,在使所述间隔件卷料折曲或弯曲而形成了在间隔件卷料整个宽度延伸的凸部的状态下,以凸部位于电极卷料侧的相反侧的方式进行贴合；切断机构,其在设置有凸部的部分将间隔件卷料和电极卷料的贴合体的至少电极卷料部分切断。(The present invention provides an efficient manufacturing technique for a secondary battery laminate having a spacer and an electrode, which enables a laminate type secondary battery to be manufactured continuously and efficiently. The apparatus for manufacturing a secondary battery laminate according to the present invention includes: an electrode roll formed by rolling a long electrode roll material into a roll shape; a separator roll formed by rolling a long separator roll material into a roll shape; a bonding mechanism that bonds a separator roll that has been paid out from a separator roll and an electrode roll that has been paid out from an electrode roll, such that the convex portions are positioned on the opposite side of the electrode roll side, in a state in which the separator roll is bent or curved to form convex portions that extend across the entire width of the separator roll; and a cutting mechanism for cutting at least the electrode roll material portion of the bonded body of the separator roll material and the electrode roll material at the portion provided with the convex portion.)

1. An apparatus for manufacturing a secondary battery laminate, comprising:

an electrode roll formed by rolling a long electrode roll material into a roll shape;

a separator roll formed by rolling a long separator roll material into a roll shape;

a bonding mechanism that bonds the separator roll that has been paid out from the separator roll and the electrode roll that has been paid out from the electrode roll, such that the convex portion is positioned on the opposite side of the electrode roll side, in a state in which the separator roll is bent or curved to form a convex portion that extends over the entire width of the separator roll; and

and a cutting mechanism that cuts at least the electrode roll portion of the bonded body of the separator roll and the electrode roll at a portion where the convex portion is provided.

2. The manufacturing apparatus of a laminate for a secondary battery according to claim 1, wherein,

the attaching mechanism has: a crimping machine that sandwiches the separator roll and the electrode roll with a separator roll side pressing member and an electrode roll side pressing member and bonds the separator roll and the electrode roll,

the spacer roll-side pressing member includes: a concave part with a shape corresponding to the convex part, and a suction part for sucking the spacer coil material to be absorbed in the concave part.

3. The manufacturing apparatus of a laminate for a secondary battery according to claim 2, wherein,

the spacer-roll-side pressing member and the electrode-roll-side pressing member are pressure contact rollers.

4. The manufacturing apparatus of a laminate for a secondary battery according to claim 2 or 3, wherein,

the spacer roll-side pressing member has a plurality of recesses arranged in line,

the surface area of each concave portion gradually increases or gradually decreases toward the arrangement direction of the concave portions.

5. The manufacturing apparatus of a laminate for a secondary battery according to any one of claims 1 to 4, wherein,

the convex part has: first and second projections extending across the width of the spacer roll, and a valley between the first and second projections.

6. A method for manufacturing a laminate for a secondary battery, comprising:

a step (A) of bonding a separator roll material, which is unwound from a separator roll formed by winding an elongated separator roll material, and an electrode roll material, which is unwound from an electrode roll formed by winding an elongated electrode roll material, to each other so that the convex portions are positioned on the opposite side of the electrode roll material side, in a state where the separator roll material is bent or curved to form convex portions extending over the entire width of the separator roll material;

And a step B of cutting at least the electrode roll portion of the bonded body of the separator roll and the electrode roll obtained in the step a at a portion where the convex portion is provided.

7. The method for producing a laminate for a secondary battery according to claim 6, wherein,

in the step a, an electrode roll-side pressing member, and a spacer roll-side pressing member having a concave portion having a shape corresponding to the convex portion and a suction portion for sucking the spacer roll and sucking it into the concave portion are used, and the spacer roll and the electrode roll are bonded by sandwiching the spacer roll and the electrode roll between the electrode roll-side pressing member and the spacer roll-side pressing member while sucking the spacer roll and sucking it into the concave portion.

8. The method for producing a laminate for a secondary battery according to claim 7, wherein,

the spacer roll-to-roll pressing member and the electrode roll-to-roll pressing member are pressure contact rollers.

9. The method for producing a laminate for a secondary battery according to any one of claims 6 to 8, wherein,

in the step a, the plurality of projections are formed such that the surface area of each projection gradually increases or gradually decreases in the direction in which the spacer roll is conveyed.

10. The method for producing a laminate for a secondary battery according to any one of claims 6 to 9, wherein,

the projections have first and second projections extending across the width of the spacer roll, and a valley between the first and second projections.

Technical Field

The present invention relates to an apparatus for manufacturing a secondary battery laminate and a method for manufacturing a secondary battery laminate.

Background

Secondary batteries such as lithium ion secondary batteries are small and lightweight, have high energy density, and are capable of repeated charge and discharge, and are used in a wide range of applications. In general, a secondary battery includes a battery member such as a positive electrode, a negative electrode, and a separator for separating the positive electrode and the negative electrode from each other to prevent a short circuit between the positive electrode and the negative electrode.

Here, as the structure of the secondary battery, a laminate type in which a positive electrode, a separator, and a negative electrode are alternately laminated, and a winding type in which a long positive electrode, a long separator, and a long negative electrode are laminated and wound in concentric circles are known. In recent years, attention has been particularly paid to a laminated secondary battery from the viewpoint of excellent energy density, safety, quality, and durability.

As a method for manufacturing a laminated secondary battery, for example, a method of alternately laminating a first electrode and a second electrode, which are wrapped with a spacer, has been proposed (for example, see patent document 1). Specifically, in patent document 1, a laminated secondary battery is manufactured by sandwiching a first strip-shaped electrode web from both sides with a strip-shaped spacer roll having a plurality of folded portions formed in the short-side direction, bonding the first strip-shaped electrode web and the contact portion of the strip-shaped spacer roll, then cutting the first strip-shaped electrode web and the strip-shaped spacer roll at the folded portions, sealing the cut pieces (first electrodes) of the first strip-shaped electrode web at the folded portions of the spacers, and alternately laminating the obtained spacer seal of the first electrode and the second electrodes.

Disclosure of Invention

Problems to be solved by the invention

However, in the method for manufacturing a laminated secondary battery described in patent document 1, a first strip-shaped electrode roll and a strip-shaped separator roll having a folded portion, which are prepared in advance and have substantially the same length in the longitudinal direction, are bonded and cut to prepare a laminate of a first electrode and a separator. Therefore, in the technique described in patent document 1, when a plurality of stacked bodies are required to continuously manufacture the stacked secondary battery, the preparation, bonding, and cutting of each member (coil stock) need to be alternately repeated, and the stacked secondary battery cannot be continuously and efficiently manufactured.

In order to solve such a problem, it is conceivable to manufacture a laminate of an electrode and a separator by a roll-to-roll (roll) method using a long electrode roll wound in a roll and a long separator roll wound in a roll. However, in the laminated secondary battery, a laminate having a larger spacer size than the electrode is generally required from the viewpoint of safety such as prevention of short-circuiting, and when the laminate is manufactured by a roll-to-roll method, since the stacked electrode roll and spacer roll are cut, there is a problem that the sizes of the electrode and the spacer between the cut positions are the same.

Accordingly, an object of the present invention is to provide an efficient manufacturing method of a laminate for a secondary battery having a separator and an electrode, which can continuously and efficiently manufacture a laminate type secondary battery.

Means for solving the problems

The present invention is directed to advantageously solve the above problems, and an apparatus for manufacturing a laminate for a secondary battery according to the present invention includes: an electrode roll formed by rolling a long electrode roll material into a roll shape; a separator roll formed by rolling a long separator roll material into a roll shape; a bonding mechanism that bonds the separator roll that has been paid out from the separator roll and the electrode roll that has been paid out from the electrode roll, such that the convex portion is positioned on the opposite side of the electrode roll side, in a state in which the separator roll is bent or curved to form a convex portion that extends over the entire width of the separator roll; and a cutting mechanism that cuts at least the electrode roll portion of the bonded body of the separator roll and the electrode roll at a portion where the convex portion is provided. In this manner, by providing the bonding mechanism and the cutting mechanism and bonding and cutting the separator roll discharged from the separator roll and the electrode roll discharged from the electrode roll, it is possible to continuously manufacture the secondary battery laminate. In the laminating mechanism, the separator roll is laminated to the electrode roll in a state where the protrusions (bent portions or bent portions) are formed on the separator roll, and the cutting mechanism cuts at least the electrode roll portion at the portion where the protrusions are provided, whereby a laminate for a secondary battery having a larger size of the separator than the electrode can be obtained. Therefore, a secondary battery laminate can be efficiently produced, and a laminate for a secondary battery, which enables a laminate type secondary battery to be continuously and efficiently produced, can be efficiently produced.

Here, in the apparatus for manufacturing a secondary battery laminate according to the present invention, it is preferable that the bonding mechanism includes: a crimping machine that sandwiches and bonds the spacer roll and the electrode roll with a spacer roll side pressing member and an electrode roll side pressing member, the spacer roll side pressing member having: a concave part with a shape corresponding to the convex part, and a suction part for sucking the spacer coil material to be absorbed in the concave part. By using the spacer roll-side pressing member having the concave portion and the suction portion, the spacer roll and the electrode roll can be continuously bonded more efficiently in a state where the convex portion (the bent portion or the curved portion) is formed in the spacer roll.

In the apparatus for manufacturing a secondary battery laminate according to the present invention, the separator roll-side pressing member and the electrode roll-side pressing member are preferably pressure contact rollers. By using the pressure-bonding roller, the separator roll and the electrode roll can be continuously bonded more efficiently.

In the apparatus for manufacturing a secondary battery laminate according to the present invention, it is preferable that the separator roll-side pressing member has a plurality of recesses arranged in an array, and a surface area of each recess gradually increases or gradually decreases in a direction in which the recesses are arranged. By using a spacer roll-side pressing member in which a plurality of recesses are arranged such that the surface area of each recess gradually increases or gradually decreases in the direction of arrangement, a laminate can be obtained in which a plurality of electrodes are bonded to a long spacer and the distance between the electrodes gradually increases or gradually decreases. Moreover, the laminated secondary battery can be efficiently and easily manufactured using the laminate.

In the apparatus for manufacturing a secondary battery laminate according to the present invention, it is preferable that the convex portion includes: first and second projections extending across the width of the spacer roll, and a valley between the first and second projections. If the convex portion has a first convex portion, a second convex portion, and a valley portion, the bonded body of the separator roll material and the electrode roll material can be easily cut at the valley portion.

In addition, an object of the present invention is to advantageously solve the above-mentioned problems, and a method for manufacturing a laminate for a secondary battery according to the present invention includes: a step (A) of bonding a separator roll material, which is unwound from a separator roll formed by winding an elongated separator roll material, and an electrode roll material, which is unwound from an electrode roll formed by winding an elongated electrode roll material, to each other so that the convex portions are positioned on the opposite side of the electrode roll material side, in a state where the separator roll material is bent or curved to form convex portions extending over the entire width of the separator roll material; and a step B of cutting at least the electrode roll portion of the bonded body of the separator roll and the electrode roll obtained in the step a at a portion where the convex portion is provided. In this way, the separator roll discharged from the separator roll and the electrode roll discharged from the electrode roll are bonded and cut, and the secondary battery laminate can be continuously manufactured. In addition, in the step a, the separator roll is bonded to the electrode roll in a state where the convex portions (bent portions or bent portions) are formed on the separator roll, and in the step B, at least the electrode roll is cut at the portions where the convex portions are provided, whereby a secondary battery laminate having a larger size of the separator than the electrode can be obtained. Therefore, a laminate for a secondary battery, which enables a laminated secondary battery to be continuously and efficiently manufactured, can be efficiently manufactured.

In the method for manufacturing a secondary battery laminate according to the present invention, it is preferable that in the step a, an electrode roll-side pressing member, and a spacer roll-side pressing member having a concave portion having a shape corresponding to the convex portion and a suction portion for sucking the spacer roll and sucking it in the concave portion are used, and the spacer roll and the electrode roll are bonded to each other by sandwiching the spacer roll and the electrode roll between the electrode roll-side pressing member and the spacer roll-side pressing member while sucking the spacer roll and sucking it in the concave portion. By using the spacer roll-side pressing member having the concave portion and the suction portion, the spacer roll and the electrode roll can be continuously bonded more efficiently in a state where the convex portion (the bent portion or the curved portion) is formed in the spacer roll.

In the method for producing a laminate for a secondary battery according to the present invention, the separator roll-side pressing member and the electrode roll-side pressing member are preferably pressure contact rollers. By using the pressure-bonding roller, the separator roll and the electrode roll can be continuously bonded more efficiently.

In the method for producing a secondary battery laminate according to the present invention, in the step a, the plurality of projections are preferably formed such that the surface area of each projection gradually increases or gradually decreases in the direction in which the separator roll is conveyed. In the step a, a plurality of projections are formed such that the surface area of each projection gradually increases or gradually decreases in the conveying direction, and in the step B, the electrode roll portion is cut, whereby a laminate in which a plurality of electrodes are bonded to a long spacer and the distance between the electrodes gradually increases or gradually decreases can be obtained. Moreover, the laminated secondary battery can be efficiently and easily manufactured using the laminate.

In the method for manufacturing a laminate for a secondary battery according to the present invention, it is preferable that the convex portions include first convex portions and second convex portions extending over the entire width of the separator roll, and valley portions located between the first convex portions and the second convex portions. When the convex portion has the first convex portion, the second convex portion, and the valley portion, the bonded body of the separator roll material and the electrode roll material can be easily cut at the valley portion in the step (B).

Effects of the invention

According to the present invention, a laminated secondary battery can be continuously and efficiently manufactured, and a laminated body for a secondary battery having a separator and an electrode can be efficiently manufactured.

Drawings

Fig. 1 (a) is a cross-sectional view along the longitudinal direction of one example of a bonded body of a separator roll and an electrode roll, fig. 1 (b) is a cross-sectional view along the longitudinal direction of another example of a bonded body of a separator roll and an electrode roll, and fig. 1 (c) is a cross-sectional view along the longitudinal direction of another example of a bonded body of a separator roll and an electrode roll.

Fig. 2 (a) is a cross-sectional view along the stacking direction of one example of a secondary battery laminate, and fig. 2 (b) is a cross-sectional view along the stacking direction of another example of a secondary battery laminate.

Fig. 3 is a cross-sectional view of another example of the secondary battery laminate along the longitudinal direction.

Fig. 4 is an explanatory diagram illustrating a structure of an example of an electrode structure formed using the secondary battery laminate shown in fig. 2.

Fig. 5 is an explanatory diagram illustrating a process of forming an electrode structure using the secondary battery laminate shown in fig. 3.

Fig. 6 (a) to (c) are cross-sectional views along the longitudinal direction of the spacer roll showing shapes of modified examples of the convex portions formed by bending or curving the spacer roll.

Fig. 7 is an explanatory view showing a schematic configuration of a first example of an apparatus for manufacturing a secondary battery laminate.

Fig. 8 is an enlarged perspective view of the pressure-contact roller of the manufacturing apparatus shown in fig. 7.

Fig. 9 (a) is a perspective view of a first modification of the pressure roller, and fig. 9 (b) is a perspective view of a second modification of the pressure roller.

Fig. 10 is an explanatory view showing a schematic configuration of another example of the apparatus for producing a secondary battery laminate.

Detailed Description

The method for producing a secondary battery laminate of the present invention can be used, for example, when producing a secondary battery laminate using the apparatus for producing a secondary battery laminate of the present invention. The produced laminate for a secondary battery is suitable for use in the production of a laminate-type secondary battery.

Here, in the apparatus and method for manufacturing a secondary battery laminate according to the present invention, a secondary battery laminate is generally continuously manufactured using an electrode roll in which a long electrode material is wound into a roll and a separator roll in which a long separator material is wound into a roll. Specifically, in the manufacturing apparatus and the manufacturing method of the present invention, for example, the separator roll fed out from the separator roll and the electrode roll fed out from the electrode roll are bonded to each other so that the convex portion is positioned on the opposite side to the electrode roll side in a state where the convex portion extending over the entire width of the separator roll is formed by bending or curving the separator roll by using the bonding mechanism, thereby manufacturing the bonded body of the separator roll and the electrode roll. Then, for example, by using a cutting mechanism, both the separator roll and the electrode roll or only the electrode roll is cut at the portion where the convex portion is provided, thereby manufacturing a laminate for a secondary battery.

< electrode roll Material >

The electrode roll is not particularly limited, and for example, an electrode roll in which an electrode composite material layer containing an electrode active material and a binder is formed on one surface or both surfaces of a long current collector can be used. Also, known materials can be used as the materials of the current collector and the electrode composite layer.

< roll spacer >

The separator roll is not particularly limited, and a long porous member made of an organic material such as a microporous film or a nonwoven fabric containing a resin such as a polyolefin resin (for example, polyethylene, polypropylene, or the like) or an aromatic polyamide resin can be used.

The tensile modulus of elasticity of the spacer roll in the direction in which the spacer roll is unwound from the spacer roll (the transport direction) is preferably 400MPa or more and 4500MPa or less. The thickness of the spacer roll is usually 0.5 μm or more, preferably 1 μm or more, usually 40 μm or less, preferably 30 μm or less, and more preferably 20 μm or less. Here, in the present invention, "tensile elastic modulus of a spacer roll" means a tensile elastic modulus at a temperature of 23 ℃ measured according to JIS K7127.

< bonded body >

In the manufacturing apparatus and the manufacturing method of the present invention, the bonded body formed by the electrode roll and the spacer roll is not particularly limited, and has, for example, a structure as shown in a cross section along the longitudinal direction in fig. 1 (a) to (c).

Here, the bonded body 1 shown in fig. 1 a has a structure in which a separator roll 20 is bonded to one surface (upper side in fig. 1 a) of an electrode roll 10, the electrode roll 10 is formed by forming electrode composite material layers 12 on both surfaces of a current collector 11, and the separator roll 20 is formed by forming a plurality of projections (bent portions) 21 extending in a semicircular arc shape in cross section over the entire width at predetermined intervals.

The bonded body 1A shown in fig. 1 (b) has a structure in which a separator roll 20 is bonded to both surfaces of an electrode roll 10, the electrode roll 10 is formed by forming electrode composite material layers 12 on both surfaces of a current collector 11, and the separator roll 20 is formed by forming a plurality of projections (bent portions) 21 extending across the entire width and having a semicircular arc shape in cross section at predetermined intervals. In the bonded body 1A, the formation position of the convex portion 21 of the spacer roll 20 bonded to one surface of the electrode roll 10 coincides with the formation position of the convex portion 21 of the spacer roll 20 bonded to the other surface of the electrode roll 10. That is, the convex portions 21 of the spacer roll 20 bonded to one surface of the electrode roll 10 and the convex portions 21 of the spacer roll 20 bonded to the other surface of the electrode roll 10 face each other across the electrode roll 10. Further, the portions between the projections 21 of the separator roll 20 are bonded to the electrode roll 10.

Furthermore, the bonded body 1B shown in fig. 1c has a structure in which a separator roll 20 is bonded to one surface (the upper side of fig. 1 c) of an electrode roll 10, the electrode roll 10 being formed by forming electrode composite material layers 12 on both surfaces of a current collector 11, and the separator roll 20 being formed by forming a plurality of projections (bent portions) 21 extending in a semicircular arc shape in cross section over the entire width at predetermined intervals. In addition, in the bonded body 1B, a pattern (for example, a pattern configured by a combination of three convex portions 21A, 21B, and 21C which are successively larger in the drawing) in which the size of the convex portion 21 is gradually increased from one side (the left side of (C) in fig. 1) in the longitudinal direction to the other side (the right side of (C) in fig. 1) is repeatedly provided. The portions of the separator roll 20 between the projections 21A, 21B, 21C are bonded to the electrode roll 10.

In fig. 1 (a) to (c), the electrode roll 10 has the electrode composite material layers 12 on both surfaces of the current collector 11, but the electrode roll may have the electrode composite material layers formed only on one surface of the current collector.

In fig. 1 (a) to (c), the projection 21 is illustrated as having a semicircular arc shape in cross section, but the shape of the projection may be any shape such as the shape illustrated in fig. 6 (a) to (c). Here, the convex portion 21D shown in fig. 6 (a) is triangular, the convex portion 21E shown in fig. 6 (b) is quadrangular, and the convex portion 21F shown in fig. 6 (c) is shaped to have a first convex portion 21a and a second convex portion 21c, and a valley portion 21b located between the first convex portion 21a and the second convex portion 21 c. In particular, if a shape having a first convex portion 21a and a second convex portion 21c adjacent to each other and a trough portion 21b located between the first convex portion 21a and the second convex portion 21c is adopted as shown in fig. 6 (c), the spacer roll 20 can be easily cut in the trough portion 21 b.

< laminate for Secondary Battery >

In the manufacturing apparatus and the manufacturing method of the present invention, the laminate for a secondary battery obtained by cutting at least the electrode roll portion of the laminate at the portion provided with the convex portion has the following structure: the separator formed of a cut piece of the separator and having a size larger than that of the electrode is bonded to one surface or both surfaces of the electrode formed of the cut piece of the electrode roll, or a plurality of electrodes formed of the cut piece of the electrode roll are bonded to one surface of a long separator formed of the cut piece of the separator roll. Specifically, the secondary battery laminate is not particularly limited, and has, for example, a structure showing a cross section in the lamination direction in (a) and (b) in fig. 2, or a structure showing a cross section in the longitudinal direction in fig. 3.

Here, the laminate 2 for a secondary battery shown in fig. 2 (a) can be obtained, for example, by cutting the electrode roll 10 and the separator roll 20 of the laminate 1 shown in fig. 1 (a) at a position substantially in the center (top) of the convex portion 21. The secondary battery laminate 2 further includes: an electrode 10a formed by cutting a roll 10 of the electrode, and having electrode composite material layers 12a provided on both surfaces of a current collector 11 a; and a spacer 20a formed of a cut piece of the spacer roll 20, having a size larger than that of the electrode 10a, and attached to one surface (upper side of fig. 2 (a)) of the electrode 10 a.

In fig. 2 (a), the lengths of the portions of the spacers 20a protruding from the ends of the electrode 10a are approximately 1/2, which are the difference between the length of the protruding portion 21 cut in the bonded body 1 and the length of the electrode roll 10 at the position where the protruding portion 21 faces each other.

The laminate 2A for a secondary battery shown in fig. 2 (b) can be obtained by cutting the electrode roll 10 and the separator roll 20 of the laminate 1A shown in fig. 1 (b) at a position substantially in the center (top) of the convex portion 21, for example. The secondary battery laminate 2A further includes: an electrode 10a formed by cutting a roll 10 of the electrode, and having electrode composite material layers 12a provided on both surfaces of a current collector 11 a; and a spacer 20a formed of a cut piece of the spacer roll 20, having a size larger than that of the electrode 10a, and attached to both surfaces of the electrode 10 a.

In fig. 2 (b), the lengths of the portions of the spacers 20a protruding from the ends of the electrode 10a are approximately 1/2, which are the difference between the length of the protruding portion 21 cut in the bonded body 1 and the length of the electrode roll 10 at the position where the protruding portion 21 faces each other.

Further, if the secondary battery laminate 2 and the secondary battery laminate 2A are used, for example, as shown in fig. 4, lamination is performed, whereby an electrode structure usable for a laminate-type secondary battery can be produced.

In fig. 4, reference numeral 2 'denotes a negative electrode laminate, 10 a' denotes a negative electrode, 11a 'denotes a negative electrode current collector, 12 a' denotes a negative electrode composite material layer, 2 "denotes a positive electrode laminate, 10 a" denotes a positive electrode, 11a "denotes a positive electrode current collector, 12 a" denotes a positive electrode composite material layer, and 20a denotes a separator. In this example, the size of the positive electrode 10a ″ is made smaller than that of the negative electrode 10 a' in order to improve the safety of the secondary battery. Further, 11b is a positive electrode collector with a current lead-out terminal, and 11c is a negative electrode collector with a current lead-out terminal.

Further, the laminate 2B for a secondary battery shown in fig. 3 can be obtained by: for example, in the bonded body 1B shown in fig. 1 (C), the electrode roll 10 and the spacer roll 20 are cut at the substantially central (top) position of the convex portion 21A, and only the electrode roll 10 is cut at the position facing the substantially central (top) position of the convex portion 21B and the convex portion 21C. The secondary battery laminate 2B has the following structure: a plurality of (three in the drawing) electrodes 10a are bonded to one surface of a long separator 20a formed from cut pieces of a separator roll 20, the electrodes 10a are formed from the cut pieces of the electrode roll 10, and electrode composite material layers 12a are provided on both surfaces of a current collector 11 a.

In fig. 3, the distances L1 and L2 of the electrode 10a correspond to the lengths of the projections 21B and 21C that are not cut in the bonded body 1B, respectively.

Further, if the secondary battery laminate 2B is used, an electrode structure usable for a laminated secondary battery can be produced by laminating and winding as shown in fig. 5, for example. The electrode structure has a structure in which n first electrodes (negative electrodes or positive electrodes; negative electrodes 10 a' in the drawing) and n-1 second electrodes (positive electrodes or negative electrodes; positive electrodes 10a "in the drawing) are alternately laminated, and has a structure in which a first laminate in which n-1 first electrodes are bonded to one surface of a long spacer at predetermined intervals, and a second laminate in which n-1 second electrodes are bonded to one surface of the long spacer at predetermined intervals, and one first electrode is bonded to the other surface of the spacer so as to face the second electrode located at one end side in the longitudinal direction of the spacer are laminated so that the spacer of the first laminate is located at one end side in the longitudinal direction of the first laminate, and the second laminate in which n-1 second electrodes are bonded to one surface of the long spacer at predetermined intervals, and the first electrode is wound around the other end side in the longitudinal direction of the second laminate And (4) obtaining.

In other words, the electrode structure shown in fig. 5 includes: the first laminate is formed by bonding a plurality of first electrodes to one surface of an elongated first spacer while being spaced apart from each other in the longitudinal direction of the first spacer, and the second laminate is formed by bonding a plurality of second electrodes to one surface of an elongated second spacer while being spaced apart from each other in the longitudinal direction of the second spacer, and bonding one first electrode to the other surface of the second spacer so as to face a second electrode located on one end side in the longitudinal direction of the second spacer. The first spacer and the second spacer are wound around the first electrode of the second laminate as a winding center.

In the case of forming an electrode structure, the spacer may be loosened or tightened during winding, but the "predetermined interval" between adjacent electrodes generally means a length at which the first electrode and the second electrode can be vertically aligned, which is equal to or greater than the total thickness of all the electrodes and the spacer sandwiched between the electrodes during winding.

In fig. 5, reference numeral 2 'denotes a negative electrode laminate, 10 a' denotes a negative electrode, 2 ″ denotes a positive electrode laminate, 10a ″ denotes a positive electrode, and 20a denotes a separator. In this example, the negative electrode 10 a' located on one end side of the positive electrode laminate 2 ″ and facing the positive electrode 10a ″ with the separator 20a interposed therebetween can be disposed on the separator 20a by any method used in the production of secondary batteries. The distance between the electrodes (negative electrode 10a ', positive electrode 10a ") may be equal to or greater than the total thickness of the negative electrode 10a ', positive electrode 10 a", and separator 20a interposed between the electrodes during winding, and the length of the negative electrode 10a ' and positive electrode 10a "may be aligned in the vertical direction. In this example, the size of the positive electrode 10a ″ is smaller than that of the negative electrode 10 a' from the viewpoint of improving the safety of the secondary battery.

< apparatus and method for producing laminate for secondary battery >

The secondary battery laminate described above can be manufactured using, for example, the manufacturing apparatus 100 shown in fig. 7.

The manufacturing apparatus 100 shown in fig. 7 includes: an electrode roll 10' formed by rolling a long electrode roll 10 into a roll shape; a separator roll 20' formed by rolling up a long separator roll 20; a rubber roller 30 and an adsorption roller 40 as pressure contact rollers for sandwiching and pressure contacting the electrode roll 10 and the spacer roll 20; and a cutting mechanism 50 for cutting the bonded body of the separator roll 20 and the electrode roll 10. The manufacturing apparatus 100 further includes a transport roller 60 that transports the electrode roll 10 and the spacer roll 20, a tension buffer 70 that adjusts the tension of the spacer roll 20, and an acceleration device 80 that increases the transport speed of the spacer roll 20. Further, according to the manufacturing apparatus 100, for example, the bonded body 1 shown in fig. 1 (a) can be formed and cut by the cutting mechanism 50 to obtain the secondary battery laminate 2 shown in fig. 2 (a).

Here, the suction roller 40 has a concave portion 41 having a shape (semicircular arc shape) corresponding to the convex portion 21 of the bonded body 1 formed and cut in the manufacturing apparatus 100, and a suction portion (not shown) that sucks and sucks the spacer roll 20 in the concave portion 41. As shown by enlarging the rubber roller 30 and the suction roller 40 in fig. 8, the concave portion 41 of the suction roller 40 is provided over the entire width of the suction roller 40.

The tension damper 70, the accelerator 80, the metal roller 30, and the suction roller 40 function as a bonding means, and the separator roll 20 discharged from the separator roll 20 'and the electrode roll 10 discharged from the electrode roll 10' are bonded so that the convex portions 21 are positioned on the opposite side to the electrode roll 10 side in a state where the convex portions 21 extending over the entire width of the separator roll 20 are formed by bending the separator 20 by being sucked into the concave portions 41 of the suction roller 40. In the bonding mechanism, the rubber roller 30 and the suction roller 40 function as a crimping machine, the rubber roller 30 is an electrode-roll-side pressing member of the crimping machine, and the suction roller 40 is a spacer-roll-side pressing member of the crimping machine.

According to this manufacturing apparatus 100, the separator roll 20 fed out from the separator roll 20 'and the electrode roll 10 fed out from the electrode roll 10' can be bonded together such that the convex portions 21 are positioned on the opposite side to the electrode roll 10 side in a state where the convex portions 21 extending over the entire width of the separator roll 20 are formed by sucking and bending the separator 20 in the concave portions 41 of the suction roller 40 (step (a)). The laminate of the separator roll 20 and the electrode roll 10 obtained in the step (a) is cut at the portion where the convex portion 21 is provided, whereby the laminate 2 for a secondary battery shown in fig. 2(a) can be obtained (step (B)). Therefore, a secondary battery laminate having a larger separator size than the electrode can be continuously produced. As a result, the laminated secondary battery can be continuously and efficiently manufactured.

Here, in the manufacturing apparatus 100, in order to manufacture the laminate 2 for a secondary battery shown in fig. 2 (a) by forming the bonded body 1 shown in fig. 1 (a) and cutting the bonded body with the cutting mechanism 50, the suction roller 40 having 4 concave portions 41 having the same shape is used, but in the case of manufacturing the laminate 2B for a secondary battery shown in fig. 3 by forming the bonded body 1B shown in fig. 1 (c), the suction roller 40A shown in fig. 9 (a) may be used instead of the suction roller 40.

The suction roller 40A has a plurality of (4 in the drawing) concave portions 41A, 41B, 41C, 41D arranged in a circumferential direction of the suction roller 40A, and the surface area of each of the concave portions 41A, 41B, 41C, 41D gradually increases or gradually decreases (gradually increases counterclockwise in the drawing) in a direction in which the concave portions 41A, 41B, 41C, 41D are arranged. That is, in the suction roller 40A, the sizes of the concave portions 41A, 41B, 41C, and 41D increase in order.

In the case of manufacturing the laminate 2B for a secondary battery shown in fig. 3 using the suction roller 40A, for example, the rubber roller 30 and the suction roller 40A are bonded to each other with the projections formed by the recesses 41A, 41B, 41C, and 41D, the cutting mechanism cuts the electrode roll 10 and the spacer roll 20 at the portions where the minimum-sized projections are formed by the minimum-sized recesses 41A, and the cutting mechanism cuts only the electrode roll 10 at the portions where the projections formed by the recesses 41A, 41B, 41C, and 41D are located. In this way, the secondary battery laminate 2B shown in fig. 3 can be efficiently obtained, and the electrode structure shown in fig. 5 can be produced, whereby the laminated secondary battery can be continuously and efficiently produced.

The cutting mechanism can cut only the electrode web 10, and for example, can be performed by providing a cutting blade (not shown) on the opposite side of the electrode web 10 from the spacer web 20 and moving the cutting blade to a position between the electrode web 10 and the convex portion of the spacer web 20.

In the case where the laminate 2 for a secondary battery shown in fig. 2 (a) is manufactured by forming a laminate having the convex portions 21F having the shape shown in fig. 6 (c), the suction roller 40B shown in fig. 9 (B) may be used instead of the suction roller 40.

The adsorption roller 40B has a concave portion 41F having a first concave portion 41a and a second concave portion 41c having shapes corresponding to the first convex portion 21a and the second convex portion 21c, and a top portion 41B having a shape corresponding to the valley portion 21B between the mutually adjacent first concave portion 41a and 2 nd concave portion 41 c.

When the laminate 2 for a secondary battery shown in fig. 2 (a) is manufactured by forming a laminate having the convex portions 21F having the shape shown in fig. 6 (c) using the suction roller 40B, for example, the rubber roller 30 and the suction roller 40B laminate the separator roll 20 and the electrode roll 10 while forming the convex portions 21F using the concave portions 41F, and the cutting mechanism cuts the electrode roll 10 and the separator roll 20 at the positions of the valley portions 21B of the convex portions 21F. In this way, a secondary battery laminate having a larger spacer size than the electrode can be continuously and efficiently produced. As a result, the laminated secondary battery can be continuously and efficiently manufactured.

In the above description, the case of manufacturing the laminate for a secondary battery in which the separator is bonded to one surface of the electrode roll 10 by forming the bonded body in which the separator roll 20 is bonded to one surface of the electrode roll 10 and cutting the bonded body by the cutting mechanism has been described, but, for example, the manufacturing apparatus 100A shown in fig. 10 can be used in the case of manufacturing the laminate for a secondary battery 2A shown in fig. 2 (b) by forming the bonded body in which the separator roll 20 is bonded to both surfaces of the electrode roll 10.

In fig. 10, the same reference numerals as in fig. 7 are assigned to members having the same configurations as in fig. 7, and the description thereof will be omitted.

Further, according to the manufacturing apparatus 100A, the separator roll 20 fed out from the two separator rolls 20 'and the electrode roll 10 fed out from the electrode roll 10' and positioned between the separator rolls 20 can be bonded to each other by using the pair of suction rolls 40 as pressure contact rolls so that the convex portions 21 are positioned on the opposite side to the electrode roll 10 side in a state where the separator roll 20 is bent by the concave portions 41 of the suction rolls 40 to form the convex portions 21 extending over the entire width of the separator roll 20 (step (a)). The laminate of the separator roll 20 and the electrode roll 10 obtained in the step (a) is cut at the portion where the convex portion 21 is provided, whereby a laminate 2A for a secondary battery shown in fig. 2 (B) can be obtained (step (B)). Therefore, a secondary battery laminate having a larger spacer size than the electrode can be continuously produced. As a result, the laminated secondary battery can be continuously and efficiently manufactured.

In the manufacturing apparatus 100A, the bonded body having the convex portions 21 on both surfaces is conveyed without particular limitation, and for example, it can be conveyed by using a lift-type conveying mechanism such as a conveying roller or an air-lift roller having a concave portion with a shape corresponding to the shape of the convex portions 21.

The apparatus and method for manufacturing a secondary battery laminate according to the present invention have been described above using examples, but the apparatus and method for manufacturing a secondary battery laminate according to the present invention are not limited to the above examples.

For example, a die or the like may be used as a crimping machine for sandwiching and bonding the spacer roll and the electrode roll. In this case, a concave portion having a shape corresponding to the convex portion and a suction portion for sucking and sucking the spacer roll in the concave portion may be formed in a mold portion serving as the spacer roll side pressing member.

The convex portion may be formed by the concave portion, or by pressing and/or static electricity to make the separator roll follow the surface of the concave portion. Further, in the case where the bonded body is difficult to form, convey, and cut while maintaining the shape of the convex portion because the spacer roll is flexible, such as when the tensile elastic modulus in the conveyance direction of the spacer roll is 400MPa to 4500MPa, and/or when the thickness of the spacer roll is 0.5 μm to 40 μm, the spacer roll may be heated in the concave portion to apply a folding mark, or a shape holding member that holds the convex portion may be disposed between the spacer roll and the electrode roll.

Possibility of industrial use

According to the manufacturing apparatus and the manufacturing method of the present invention, the laminated secondary battery can be continuously and efficiently manufactured, and the laminate for the secondary battery having the separator and the electrode can be efficiently manufactured.

Description of the reference numerals

1. 1A, 1B bonded body

2. Laminate for 2A and 2B secondary batteries

2' cathode laminate

2' positive electrode laminate

10 electrode coil stock

10a electrode

10a' negative electrode

10a' positive electrode

10' electrode roll

11 Current collector

11a current collector

11 a' negative electrode collector

11 a' positive electrode collector

11b Positive electrode collector with Current lead-out terminal

11c negative electrode collector with current lead-out terminal

12 electrode composite layer

12a electrode composite layer

12 a' negative electrode composite layer

12 a' positive electrode composite material layer

20 spacer roll

20a spacer

20' spacer roll

21 convex part

21A, 21B, 21C, 21D, 21E, 21F protrusions

21a first convex part

21b trough part

21c second convex part

30 rubber roller

40. 40A, 40B suction roll

41. 41A, 41B, 41C, 41D, 41F recesses

41a first recess

41b top part

41c second recess

50 cutting mechanism

60 transfer roll

70 tension buffer

80 accelerating device

100. 100A manufacturing device