JP2023103563A - Battery electrode manufacturing device and battery electrode manufacturing method - Google Patents

Abstract

To suppress variations in film thickness of an active material after roll pressing.SOLUTION: A battery electrode manufacturing device includes a supply unit that supplies an active material to a strip-shaped base film, a conveying unit that conveys the base film on which the active material is placed, which is supplied from the supply unit, a first press unit that compresses the active material supplied to the base film, a first inspection unit that inspects the film thickness of the active material supplied to the base film after being compressed by the first press unit, and a second press unit that compresses the active material on the basis of the inspection result of the film thickness by the first inspection unit, and the second press unit includes a division roller divided in the width direction, and at least one of the division rollers is a roller that adjusts the film thickness of the end portion of the active material.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present invention relates to a battery electrode manufacturing apparatus and a battery electrode manufacturing method.

Lithium ion batteries are high-capacity secondary batteries and have been used in various applications in recent years. An electrode of a lithium ion battery is composed of an active material layer, a current collector layer, a separator, a frame enclosing the active material layer, and the like (see, for example, Patent Document 1).

An active material layer in a lithium ion battery can be formed, for example, by supplying an active material to a strip-shaped base film and rolling it by roll pressing. For example, in Patent Document 2, an active material is supplied to a sheet-shaped current collector that is a strip-shaped base film, and the active material is rolled once with a pair of rollers as a first rolling step, followed by a second rolling. As a process, a high-density active material layer is formed by rolling the active material in multiple stages using a plurality of pairs of rollers.

Japanese Patent No. 6633866 Japanese Patent No. 6067636

It is known that the film thickness of the active material after roll-pressing varies even when simple roll-pressing is performed, or even when multistage roll-pressing is performed as in Patent Document 2. For example, the widthwise ends of the active material after roll-pressing may become thicker than the central portion.

The present invention has been made in view of the above circumstances, and aims to provide a battery electrode manufacturing apparatus and a battery electrode manufacturing method capable of suppressing variations in film thickness of the active material after roll pressing. aim.

In order to achieve the above object, the battery electrode manufacturing apparatus according to the present invention includes a supply unit that supplies an active material to a strip-shaped base film, and the A conveying section that conveys a base film, a first pressing section that compresses the active material supplied to the base film, and the active material supplied to the base film after being compressed by the first pressing section. and a second press section for compressing the active material based on the inspection result of the film thickness by the first inspection section, wherein the second press section is in the width direction At least one of the divided rollers is a roller for adjusting the film thickness of the edge of the active material.

According to the battery electrode manufacturing apparatus and the battery electrode manufacturing method of the present invention, it is possible to suppress variation in film thickness of the active material after roll pressing.

FIG. 1 is a schematic cross-sectional view of a single cell of a battery manufactured using the battery electrode manufacturing apparatus of the embodiment. FIG. 2 is a schematic diagram of the battery electrode manufacturing apparatus of the embodiment. FIG. 3 is a perspective view showing the upper roller of the embodiment. FIG. 4 is a schematic diagram of the battery electrode manufacturing apparatus of the embodiment. FIG. 5 is a perspective view showing the upper roller of the embodiment.

Embodiments to which the present invention is applied will be described below with reference to the drawings. In addition, in the drawings used in the following explanations, characteristic parts may be enlarged for the sake of convenience for the purpose of emphasizing the characteristic parts, and the dimensional ratios, etc. of each component may not necessarily be the same as the actual ones. do not have. Also, for the same purpose, some parts may be omitted from the drawings.

<Assembled battery (secondary battery)>
The battery electrode manufacturing apparatus and the battery electrode manufacturing method of the embodiments are applied, for example, to the manufacture of lithium ion batteries. Lithium ion batteries are assembled batteries that are modularized by combining a plurality of lithium ion single cells (also referred to as single cells or battery cells), or battery packs that are made by combining multiple such assembled batteries and adjusting the voltage and capacity. used in the form.

<Single cell (battery cell)>
FIG. 1 is a schematic cross-sectional view of a single cell 10. FIG. By combining a plurality of unit cells 10, the above assembled battery can be produced. For example, the single cell 10 has a positive electrode 20 a and a negative electrode 20 b as two electrodes 20 (battery electrodes) and a separator 30 .

The separator 30 is arranged between the positive electrode 20a and the negative electrode 20b. In the assembled battery, the plurality of unit cells 10 are stacked with the positive electrode 20a and the negative electrode 20b directed in the same direction.

The separator 30 holds an electrolyte. Thereby, the separator 30 functions as an electrolyte layer. The separator 30 is arranged between the electrode active material layers 22 of the positive electrode 20a and the negative electrode 20b to prevent them from coming into contact with each other. Thereby, the separator 30 functions as a partition wall between the positive electrode 20a and the negative electrode 20b.

The electrolyte held in the separator 30 includes, for example, an electrolytic solution or a gel polymer electrolyte. High lithium ion conductivity is ensured by using these electrolytes. Examples of the form of the separator include porous sheet separators and non-woven fabric separators made of polymers or fibers that absorb and retain the electrolyte.

The positive electrode 20 a and the negative electrode 20 b each have a current collector 21 , an electrode active material layer 22 and a frame 35 . The electrode active material layer 22 and the current collector 21 are arranged in this order from the separator 30 side. The frame 35 is frame-shaped (annular). The frame 35 surrounds the electrode active material layer 22 . The frame 35 of the positive electrode 20a and the frame 35 of the negative electrode 20b are welded together and integrated. In the following description, when distinguishing between the electrode active material layers 22 of the positive electrode 20a and the negative electrode 20b, they are referred to as a positive electrode active material layer 22a and a negative electrode active material layer 22b, respectively.

<Specific example of positive electrode current collector>
As the positive electrode current collector constituting the positive electrode current collector layer 21a, a known current collector used for a lithium ion single battery can be used. A resin current collector (such as the resin current collector described in JP-A-2012-150905 and WO 2015/005116) can be used. The positive electrode current collector constituting the positive electrode current collector layer 21a is preferably a resin current collector from the viewpoint of battery characteristics and the like.

Metal current collectors include, for example, copper, aluminum, titanium, nickel, tantalum, niobium, hafnium, zirconium, zinc, tungsten, bismuth, antimony, alloys containing one or more of these metals, and the group consisting of stainless alloys. and one or more metal materials selected from These metal materials may be used in the form of thin plates, metal foils, or the like. Alternatively, a metal current collector formed by forming the above metal material on the surface of a base material other than the above metal material by sputtering, electrodeposition, coating, or the like may be used.

The resin current collector preferably contains a conductive filler and a matrix resin. Examples of the matrix resin include polyethylene (PE), polypropylene (PP), polymethylpentene (PMP) and the like, but are not particularly limited. Also, the conductive filler is not particularly limited as long as it is selected from materials having conductivity. The conductive filler may be a conductive fiber having a fibrous shape.

The resin current collector may contain other components (dispersant, cross-linking accelerator, cross-linking agent, colorant, ultraviolet absorber, plasticizer, etc.) in addition to the matrix resin and the conductive filler. Also, a plurality of resin current collectors may be laminated and used, or a resin current collector and a metal foil may be laminated and used.

Although the thickness of the positive electrode current collector layer 21a is not particularly limited, it is preferably 5 to 150 μm. When a plurality of resin current collectors are laminated and used as the positive electrode current collector layer 21a, the total thickness after lamination is preferably 5 to 150 μm. The positive electrode current collector layer 21a can be obtained, for example, by molding a conductive resin composition obtained by melt-kneading a matrix resin, a conductive filler, and a dispersing agent for a filler used if necessary into a film by a known method. can be done.

<Specific example of positive electrode active material>
The positive electrode active material layer 22a is preferably a non-bound mixture containing a positive electrode active material. Here, the non-bound body means that the position of the positive electrode active material is not fixed in the positive electrode active material layer, and the positive electrode active materials and the positive electrode active material and the current collector are not irreversibly fixed. means When the positive electrode active material layer 22a is a non-bound body, the positive electrode active materials are not irreversibly fixed to each other. Even when stress is applied to the material layer 22a, the positive electrode active material moves, which is preferable because the destruction of the positive electrode active material layer 22a can be prevented. The positive electrode active material layer 22a, which is a non-binder, can be obtained by a method such as changing the positive electrode active material layer 22a into a positive electrode active material layer 22a containing a positive electrode active material and an electrolytic solution but not containing a binder. can. In this specification, the binder means an agent that cannot reversibly fix the positive electrode active materials together and the positive electrode active material and the current collector, and includes starch, polyvinylidene fluoride, polyvinyl alcohol, carboxyl Known solvent-drying type binders for lithium ion batteries such as methylcellulose, polyvinylpyrrolidone, tetrafluoroethylene, styrene-butadiene rubber, polyethylene and polypropylene can be used. These binders are used by dissolving or dispersing them in a solvent, and by volatilizing and distilling off the solvent, the surface solidifies without exhibiting stickiness. cannot be reversibly fixed.

Examples of the positive electrode active material include, but are not particularly limited to, a composite oxide of lithium and a transition metal, a composite oxide containing two transition metal elements, and a composite oxide containing three or more metal elements. .

The positive electrode active material may be a coated positive electrode active material in which at least part of the surface is coated with a coating material containing a polymer compound. When the positive electrode active material is covered with the coating material, the volume change of the positive electrode is moderated, and the expansion of the positive electrode can be suppressed.

As the polymer compound constituting the coating material, those described as active material coating resins in JP-A-2017-054703 and WO 2015/005117 can be preferably used.

The coating material may contain a conductive agent. As the conductive agent, the same conductive filler as contained in the positive electrode current collector layer 21a can be preferably used.

The positive electrode active material layer 22a may contain an adhesive resin. As the adhesive resin, for example, a non-aqueous secondary battery active material coating resin described in JP-A-2017-054703 is mixed with a small amount of an organic solvent to adjust its glass transition temperature to room temperature or lower. Also, those described as adhesives in JP-A-10-255805 can be preferably used. In addition, adhesive resin is a resin that does not solidify even if the solvent component is volatilized and dried, and has adhesiveness (the property of adhering by applying a slight pressure without using water, solvent, heat, etc.) means On the other hand, a solution-drying type electrode binder used as a binder is one that dries and solidifies by volatilizing a solvent component, thereby firmly adhering and fixing active materials to each other. Therefore, the binder (solution-drying type electrode binder) and the adhesive resin described above are different materials.

The positive electrode active material layer 22a may contain an electrolytic solution containing an electrolyte and a non-aqueous solvent. As the electrolyte, those used in known electrolytic solutions can be used. As the non-aqueous solvent, those used in known electrolytic solutions (eg, phosphate esters, nitrile compounds, mixtures thereof, etc.) can be used. For example, a mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC) or a mixture of ethylene carbonate (EC) and propylene carbonate (PC) can be used.

The positive electrode active material layer 22a may contain a conductive aid. As the conductive aid, a conductive material similar to the conductive filler contained in the positive electrode current collector layer 21a can be preferably used.

Although the thickness of the positive electrode active material layer 22a is not particularly limited, it is preferably 150 to 600 μm, more preferably 200 to 450 μm, from the viewpoint of battery performance.

<Specific example of negative electrode current collector>
As the negative electrode current collector constituting the negative electrode current collector layer 21b, the same one as the positive electrode current collector can be appropriately selected and used, and can be obtained by the same method. The negative electrode current collector layer 21b is preferably a resin current collector from the viewpoint of battery characteristics and the like. Although the thickness of the negative electrode current collector layer 21b is not particularly limited, it is preferably 5 to 150 μm.

<Specific example of negative electrode active material>
The negative electrode active material layer 22b is preferably a non-bonded mixture containing a negative electrode active material. The reason why the negative electrode active material layer is preferably a non-binder, and the reason why the positive electrode active material layer 22a is preferably a non-binder , and the method for obtaining the positive electrode active material layer 22a which is a non-binder.

As the negative electrode active material, for example, a carbon-based material, a silicon-based material, a mixture thereof, or the like can be used, but the material is not particularly limited.

The negative electrode active material may be a coated negative electrode active material in which at least part of the surface is coated with a coating material containing a polymer compound. When the periphery of the negative electrode active material is covered with the coating material, the volume change of the negative electrode is moderated, and the expansion of the negative electrode can be suppressed.

As the coating material, the same coating material as that constituting the coated positive electrode active material can be suitably used.

The negative electrode active material layer 22b contains an electrolytic solution containing an electrolyte and a non-aqueous solvent. As for the composition of the electrolytic solution, an electrolytic solution similar to the electrolytic solution contained in the positive electrode active material layer 22a can be preferably used.

The negative electrode active material layer 22b may contain a conductive aid. As the conductive aid, a conductive material similar to the conductive filler contained in the positive electrode active material layer 22a can be preferably used.

The negative electrode active material layer 22b may contain an adhesive resin. As the adhesive resin, the same adhesive resin as an optional component of the positive electrode active material layer 22a can be preferably used.

Although the thickness of the negative electrode active material layer 22b is not particularly limited, it is preferably 150 to 600 μm, more preferably 200 to 450 μm, from the viewpoint of battery performance.

<Specific example of separator>
Examples of the electrolyte held in the separator 30 include an electrolytic solution and a gel polymer electrolyte. By using these electrolytes, the separator 30 ensures high lithium ion conductivity. Examples of the form of the separator 30 include, but are not particularly limited to, polyethylene or polypropylene porous films.

<Specific example of frame>
The material for the frame 35 is not particularly limited as long as it is a material that is durable against the electrolytic solution. For example, a polymer material is preferable, and a thermosetting polymer material is more preferable. As a material for forming the frame 35, any material having insulating properties, sealing properties (liquid-tightness), heat resistance under the battery operating temperature, and the like may be used, and a resin material is preferably employed. More specifically, examples of the frame 35 include epoxy-based resins, polyolefin-based resins, polyurethane-based resins, and polyvinylidene fluoride resins. preferable.

<Battery Electrode Manufacturing Apparatus and Battery Electrode Manufacturing Method>
Next, the battery electrode manufacturing apparatus and the battery electrode manufacturing method of the embodiment will be described. For example, in the battery electrode manufacturing apparatus and the battery electrode manufacturing method of the embodiment, the positive electrode 20a and the negative electrode 20b are first manufactured. The method of manufacturing the positive electrode 20 a and the method of manufacturing the negative electrode 20 b mainly differ in the electrode active material contained in the electrode active material layer 22 . Here, as a method for manufacturing the electrode 20, a method for manufacturing the positive electrode 20a and the negative electrode 20b will be collectively described.

FIG. 2 is a schematic diagram of the battery electrode manufacturing apparatus 1000. As shown in FIG. For example, the battery electrode manufacturing apparatus 1000 includes a chamber 100 , a conveying device 200 , a frame supply device 300 , an active material supply device 400 , a press device 500 , an inspection device 610 and a press device 710 . The transport device 200 is an example of a transport unit. Active material supply device 400 is an example of a supply unit. The press device 500 is an example of a first press section. Inspection device 610 is an example of a first inspection unit. Press device 710 is an example of a second press section. As an example, a case where the strip-shaped base film is the strip-shaped current collector 21B will be described below.

The chamber 100 is a room whose interior can be kept under a pressure lower than the atmospheric pressure. The pressure inside the chamber 100 is reduced below atmospheric pressure by a decompression pump (not shown). The standard atmospheric pressure is approximately 1013 hPa (approximately 10 ⁵ Pa).

For example, a current collector roll 21R is arranged outside the chamber 100, and a strip-shaped current collector 21B pulled out from the current collector roll 21R is transported into the chamber 100 through a slit. Hereinafter, the strip-shaped current collector 21B may be referred to as the current collector 21B. The current collector 21B is the current collector 21 before being cut into a predetermined shape. The current collector 21B is transported at a predetermined speed along the transport direction Da. Hereinafter, the direction in which the current collector 21B is conveyed will be described as the downstream side Da1, and the opposite direction as the upstream side Da2. The external space of the chamber 100 in which the current collector roll 21R is arranged may be at normal pressure, or may be decompressed by a chamber different from the chamber 100 .

As shown in FIG. 2, the upper side in the vertical direction Db is Db1, and the lower side in the vertical direction Db is Db2. A direction orthogonal to the transport direction Da and the vertical direction Db corresponds to the width direction of the current collector 21B and the active material 22c placed on the current collector 21B.

The transport device 200 transports the current collector 21B to the downstream side Da1 in the transport direction Da. For example, the transport device 200 is a belt conveyor that supports the current collector 21B from below. After the frame 35 is supplied by the frame supply device 300, which will be described later, the conveying device 200 conveys the current collector 21B on which the frame 35 is placed. After the active material 22c is supplied by the active material supply device 400, which will be described later, the transport device 200 transports the current collector 21B on which the frame 35 and the active material 22c are placed.

The frame supply device 300 supplies the frame 35 to the conveyed current collector 21B. Although FIG. 2 shows the case where the frame supply device 300 is arranged inside the chamber 100 , the frame supply device 300 may be arranged outside the chamber 100 . For example, the frame supply device 300 has a robot arm and places the prefabricated frame 35 at a predetermined position on the conveyed current collector 21B. Note that after the frame 35 is placed on the current collector 21B and before the active material 22c is supplied, the current collector 21B and the frame 35 may be compressed by a roll press so as to sandwich them.

In FIG. 2, the prefabricated frame 35 is described as being placed on the current collector 21B, but the embodiment is not limited to this. For example, the frame 35 may be manufactured on the current collector 21B. As an example, the current collector 21B is used as a base material, and a predetermined material is discharged or applied in a predetermined shape onto the current collector 21B using a dispenser, a coater, or the like, thereby forming the frame 35 on the current collector 21B. can be formed.

The active material supply device 400 supplies the active material 22c to the strip-shaped current collector 21B transported within the chamber 100, as shown in FIG. For example, the active material supply device 400 includes a hopper that holds the active material 22c therein and a shutter that opens and closes the opening of the hopper. The active material supply device 400 can supply a desired amount of the active material 22c to a desired position in the transport direction Da on the transported current collector 21B by opening and closing the shutter.

The pressing device 500 compresses the active material 22c supplied to the current collector 21B. For example, the press device 500 has an upper roller 501 and a lower roller 502 as shown in FIG. The pressing device 500 sandwiches and compresses the active material 22c supplied to the current collector 21B between the upper roller 501 and the lower roller 502. As shown in FIG. That is, the press device 500 roll-presses the active material 22c.

The inspection device 610 inspects the film thickness of the active material 22c supplied to the current collector 21B after being compressed by the press device 500. FIG. In FIG. 2, the film thickness of the active material 22c is the thickness of the active material 22c in the vertical direction Db. The inspection device 610 includes, for example, a laser displacement meter, and inspects the film thickness at each position in the width direction of the transported active material 22c.

That is, even after the roll pressing by the press device 500 is performed, the thickness of the active material 22c may vary. The inspection device 610 inspects variations in film thickness after the roll pressing by the press device 500 is performed.

The press device 710 compresses the active material 22c based on the film thickness inspection result by the inspection device 610 . For example, the press device 710 has an upper roller 711 and a lower roller 712 as shown in FIG. Here, the upper roller 711 is composed of split rollers split in the width direction.

The roller shown in FIG. 2 will be explained in more detail with reference to FIG. FIG. 3 is a perspective view showing the upper roller 501 in the press device 500 and the upper roller 711 in the press device 710. FIG. In FIG. 3, other device configurations such as the inspection device 610, the current collector 21B, the active material 22c, the frame 35, etc. are omitted.

As shown in FIG. 3, the upper roller 711 is composed of a split roller 711a, a split roller 711b and a split roller 711c. The press device 710 also includes a control device 713 in addition to the upper roller 711 and the lower roller 712 shown in FIG. These dividing rollers have a form in which the active material 22c supplied to the current collector 21B is divided in the width direction, and can be individually operated under the control of the control device 713. FIG.

For example, the control device 713 holds the dividing roller 711a movably along the vertical direction Db. For example, the control device 713 includes an arm that holds the dividing roller 711a, a rail that holds the arm movably in the vertical direction Db, and a drive mechanism such as a motor that moves the arm in the vertical direction Db. Similarly, the control device 713 holds the dividing roller 711b and the dividing roller 711c movably along the vertical direction Db.

The control device 713 controls the dividing roller to compress the active material 22c at the portion where the film thickness variation exceeds a predetermined value based on the film thickness inspection result by the inspection device 610 . That is, the pressing device 500 performs roll pressing so that the active material 22c has a predetermined film thickness. However, due to various factors, the film thickness may not be constant, and the film thickness may vary. The control device 713 controls the dividing roller to compress the active material 22c at the portion where such variation exceeds a predetermined value. Note that the variation in film thickness may be a statistical value such as a standard deviation of the film thickness at each position in the width direction, a difference from the set value of the film thickness, a ratio to the set value, or the like. good too.

For example, the control device 713 first places each divided roller on the upper side Db1 of the active material 22c so as not to contact the active material 22c. At this time, compression of active material 22c by pressing device 710 is not performed.

Here, for example, when the film thickness variation exceeds a predetermined value at the left end of the active material 22c in FIG. The left end of the active material 22c in FIG. 3 is compressed. That is, the control device 713 controls the dividing roller 711a to compress the active material 22c at the portion where the film thickness variation exceeds a predetermined value based on the film thickness inspection result by the inspection device 610 . As a result, it is possible to eliminate or suppress variations in the film thickness of the active material 22c, thereby improving the quality of the lithium-ion battery. The dividing roller 711a is an example of a roller that adjusts the film thickness of the edge of the active material 22c.

Although FIG. 3 shows three divided rollers divided in the width direction, the number of divided rollers included in the upper roller 711 can be changed arbitrarily. Further, although FIG. 3 shows that the divided rollers 711a, 711b, and 711c are arranged at the same position in the conveying direction Da, these dividing rollers may be arranged at different positions in the conveying direction Da. good. In this case, these dividing rollers may be arranged so as to partially overlap in the width direction.

Moreover, in FIG. 3, the various rollers are illustrated simply as having a cylindrical shape. Also, the upper roller 501 and the dividing roller are illustrated as having the same diameter. However, the upper roller 501 and the split roller may have different diameters.

Further, after the roll pressing by the pressing device 500, the film thickness of the edge portions of the active material 22c is often larger than that of the central portion. Based on such knowledge, it is also possible to provide only the dividing roller for adjusting the film thickness of the end portion of the active material 22c and omit other dividing rollers such as the dividing roller 711b.

As described above, the inspection device 610 and the press device 710 can eliminate or suppress variations in the film thickness of the active material 22c roll-pressed by the press device 500 . However, even after being compressed by the press device 710, the film thickness of the active material 22c may remain uneven.

Therefore, the battery electrode manufacturing apparatus 1000 may further include an inspection device 620 and a press device 720 as shown in FIG. The inspection device 620 inspects the film thickness of the active material 22c after compression by the press device 710 . The press device 720 has an upper roller 711 and a lower roller 712 and compresses the active material 22c based on the film thickness inspection result by the inspection device 620 . Inspection device 620 is an example of a second inspection unit. The press device 720 is an example of a third press section.

The roller shown in FIG. 4 will be explained in more detail with reference to FIG. 5 is a perspective view showing the upper roller 501 in the press device 500, the upper roller 711 in the press device 710, and the upper roller 721 in the press device 720. FIG. In FIG. 5, other device configurations such as the inspection device 610 and the inspection device 620, the current collector 21B, the active material 22c, the frame 35, and the like are omitted.

As shown in FIG. 5, the upper roller 721 is composed of a split roller 721a, a split roller 721b, a split roller 721c and a split roller 721d. The press device 720 also includes a control device 723 in addition to the upper roller 721 and the lower roller 722 shown in FIG. These dividing rollers have a form in which the active material 22c supplied to the current collector 21B is divided in the width direction, and can be individually operated under the control of the control device 723. FIG. For example, the control device 723 holds each split roller included in the upper roller 721 so as to be movable along the vertical direction Db.

The control device 723 controls the dividing roller to compress the active material 22c at the portion where the film thickness variation exceeds a predetermined value based on the film thickness inspection result by the inspection device 620 . For example, when the variation in the thickness of the active material 22c on the left side of FIG. The left end of 22c in FIG. 5 is compressed. That is, the control device 723 controls the dividing roller 721a to compress the active material 22c at the portion where the film thickness variation exceeds a predetermined value based on the film thickness inspection result by the inspection device 620 . As a result, it is possible to eliminate or suppress variations in the film thickness of the active material 22c, thereby improving the quality of the lithium-ion battery. The dividing roller 721a is an example of a roller that adjusts the film thickness of the edge of the active material 22c.

As with the split rollers included in the upper roller 711, the number, position, and diameter of each split roller included in the upper roller 721 can be arbitrarily changed. Further, in the same way that the film thickness of the active material 22c after compression by the press device 710 is adjusted by the inspection device 620 and the press device 720, an additional inspection for adjusting the film thickness of the active material 22c after compression by the press device 720 is performed. A device and a press device may be further provided. The number of these additional inspection devices and press devices to be provided is not limited.

In the above-described embodiment, the dividing rollers included in the pressing device 710 and the pressing device 720 are configured to be movable in the vertical direction Db. However, embodiments are not so limited. For example, the dividing roller may be configured to be further movable in the width direction. In this case, the dividing roller moves in the width direction to a portion where the film thickness variation exceeds a predetermined value based on the inspection result by the inspection device 610 or the inspection device 620, and also moves to the lower side Db2 in the vertical direction Db. to compress the active material 22c. In this case, the number of divided rollers included in the press device 710 and the press device 720 may be one.

In the above-described embodiment, the strip-shaped base film on which the active material 22c is placed is described as the strip-shaped current collector 21B, but it is not limited to this. For example, instead of the strip-shaped current collector 21B shown in FIGS. 2 and 4, a strip-shaped separator sheet or a strip-shaped release film may be used as the base film. The strip-shaped separator sheet can be trimmed later to form the separator 30 shown in FIGS. 1A and 1B.

For example, when the separator sheet is used as the base film, the active material 22c is supplied on the separator sheet, the current collector 21B is supplied to the surface of the active material 22c opposite to the separator sheet, and the separator sheet and the current collector are supplied. By trimming the body 21B into a predetermined shape, the positive electrode 20a or the negative electrode 20b can be produced.

Further, when the release film is used as the base film, the active material 22c is supplied on the release film, the current collector 21B is supplied to the surface of the active material 22c opposite to the release film, and the release film is After recovery, a separator sheet is supplied to the surface opposite to the current collector 21B, and the current collector 21B and the separator sheet are trimmed into a predetermined shape, whereby the positive electrode 20a or the negative electrode 20b can be produced. . Instead of supplying the separator sheet and then trimming, the separator 30 may be supplied to the active material 22c.

Alternatively, the active material 22c is supplied on the release film, the separator sheet is supplied to the surface of the active material 22c opposite to the release film, and after the release film is collected, the separation film is collected on the surface opposite to the separator sheet. The positive electrode 20a or the negative electrode 20b can be produced by supplying the current collector 21B and trimming the separator sheet and the current collector 21B into a predetermined shape. Instead of supplying the current collector 21B and then trimming it, the current collector 21 trimmed into a predetermined shape may be supplied to the active material 22c.

Further, in the above-described embodiment, the description has been made on the assumption that the active material supply device 400 supplies the active material 22c to the base film. Here, the active material supply device 400 may supply the electrode composition in which the coating active material and the conductive aid are mixed to the base film, or the wet powder containing the active material 22c and the electrolytic solution. You may supply the electrode composition which is.

Such wet powder is more preferably in a pendular or funicular state. The ratio of the non-aqueous electrolyte in the wet powder is not particularly limited, but in the case of the positive electrode, the ratio of the non-aqueous electrolyte to the entire wet powder is 0.5 to 15 in order to make the pendular state or funicular state. % by weight, and in the case of the negative electrode, the proportion of the non-aqueous electrolyte is desirably 0.5 to 25% by weight of the entire wet powder.

When the active material 22c is a coated electrode active material coated with a coating material containing a polymer compound, the active material 22c is kept soft in the step of supplying the active material 22c to the base film. is desirable.

As described above, the embodiment of the present invention has been described in detail with reference to the drawings, but the specific configuration is not limited to this embodiment. is also included. Furthermore, it goes without saying that the configurations shown in the respective embodiments can be used in combination as appropriate.

10: Single cell 20: Electrode 20a: Positive electrode 20b: Negative electrode 21: Current collector 21a: Positive electrode current collector layer 21b: Negative electrode current collector layer 21B: Strip-shaped current collector 21R: Current collector roll 22: Electrode active material Layer 22a: Positive electrode active material layer 22b: Negative electrode active material layer 22c: Active material 30: Separator 35: Frame 100: Chamber 200: Transfer device 300: Frame supply device 400: Active material supply device 500: Press device 501: Upper part Roller 502: Lower roller 610: Inspection device 710: Press device 711: Upper roller 711a: Divided roller 711b: Divided roller 711c: Divided roller 712: Lower roller 713: Control device 620: Inspection device 720: Press device 721: Upper roller 721a : Division roller 721b: Division roller 721c: Division roller 721d: Division roller 722: Lower roller 723: Control device 1000: Battery electrode manufacturing device Da: Conveyance direction Da1: Downstream side Da2: Upstream side Db: Vertical direction Db1: Upper side Db2 :Lower

Claims (7)

a supply unit that supplies an active material to a strip-shaped base film;
a conveying unit that conveys the base film on which the active material is placed, which is supplied from the supply unit;
a first press section for compressing the active material supplied to the base film;
A first inspection unit that inspects the film thickness of the active material supplied to the base film after compression by the first press unit;
a second press unit that compresses the active material based on the inspection result of the film thickness by the first inspection unit;
The second press section has divided rollers divided in the width direction,
At least one of the dividing rollers is a roller for adjusting the film thickness of the end portion of the active material. A control unit that controls the split roller,
3. The control unit controls the dividing roller to compress the active material in a portion where the film thickness variation exceeds a predetermined value, based on the film thickness inspection result by the first inspection unit. 2. The battery electrode manufacturing apparatus according to 1. 3. The battery electrode manufacturing apparatus according to claim 1, further comprising a second inspection unit that inspects the film thickness after compression by the second press unit. 4. The battery electrode manufacturing apparatus according to claim 3, further comprising a third press section that compresses the active material based on the inspection result of the film thickness by the second inspection section. 5. The battery electrode manufacturing apparatus according to claim 4, wherein the third pressing section has split rollers split in the width direction. The battery electrode production according to any one of claims 1 to 5, wherein the supply unit supplies an electrode composition, which is a wet powder containing the active material and an electrolytic solution, to the base film. Device. Supplying an active material to a strip-shaped base film,
compressing the active material supplied to the transported base film by a first press unit;
After compression by the first press unit, inspecting the film thickness of the active material supplied to the base film,
Compressing the active material with a second press unit based on the inspection result of the film thickness,
The second press section has divided rollers divided in the width direction,
At least one of the dividing rollers is a roller for adjusting the film thickness of the end portion of the active material.

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