Method for manufacturing a solid electrolyte sheet, solid electrolyte sheet

Abstract

This invention provides a method for manufacturing a solid electrolyte sheet and a solid electrolyte sheet, which suppresses the occurrence of wrinkles or tears in the substrate during the production of a solid electrolyte sheet by roll-to-roll. [Solution] A method for manufacturing a solid electrolyte sheet filled with a solid electrolyte, comprising: a first step of coating one side of a substrate conveyed by roll-to-roll with a slurry containing a solid electrolyte; a second step of impregnating the coating film made of the slurry with a three-dimensional structure including a nonwoven fabric; and a third step of drying the coating film to form a solid electrolyte layer including the three-dimensional structure and obtain a solid electrolyte sheet filled with a solid electrolyte.

Description

[Technical Field]

[0001] This invention relates to a method for manufacturing a solid electrolyte sheet, and to a solid electrolyte sheet. [Background technology]

[0002] Lithium-ion batteries using solid electrolytes offer several advantages: superior safety, high reliability due to the absence of electrolyte leakage, and ease of miniaturization. Furthermore, because lithium metal can be used as the negative electrode, lithium-ion batteries using solid electrolytes can improve energy density, making them promising for applications such as high-capacity batteries for electric vehicles.

[0003] A known method for manufacturing a solid electrolyte membrane includes, for example, the steps of: preparing a laminated structure by sequentially stacking a first protective layer, a film-like first solid electrolyte material, a porous substrate, a film-like second solid electrolyte material, and a second protective layer; pressurizing the laminated structure to push the first and second solid electrolyte materials into the interior of the porous substrate and fill the pores of the porous substrate with the first and second solid electrolyte materials; and removing the first and second protective layers, wherein the pressurizing is performed by a roll press method (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 7168762 [Overview of the project] [Problems that the invention aims to solve]

[0005] In a method for manufacturing a solid electrolyte sheet having a solid electrolyte membrane, a slurry containing a solid electrolyte is coated onto one surface of a sheet-like substrate conveyed by a roll-to-roll system to form a solid electrolyte membrane. However, because the solid electrolyte membrane itself has low membrane strength, it may break or chip. Therefore, it has been difficult to form the solid electrolyte membrane to a predetermined size (area) and thickness.

[0006] This invention has been made in view of the above circumstances, and aims to provide a method for manufacturing a solid electrolyte sheet and a solid electrolyte sheet that suppresses damage or chipping of the solid electrolyte layer during the production of a solid electrolyte sheet by roll-to-roll. This will ultimately contribute to energy efficiency. [Means for solving the problem]

[0007] The present invention has the following aspects. [1] A method for manufacturing a solid electrolyte sheet filled with a solid electrolyte, A first step involves coating one side of a substrate being transported by roll-to-roll with a slurry containing a solid electrolyte, A second step involves impregnating the coating film, which consists of the slurry, with a three-dimensional structure including a nonwoven fabric. A method for manufacturing a solid electrolyte sheet, comprising: a third step of drying the coating film to form a solid electrolyte layer including the three-dimensional structure, thereby obtaining a solid electrolyte sheet filled with a solid electrolyte.

[0008] According to the above embodiment, the three-dimensional structure compensates for the rigidity of the substrate, and it is possible to suppress the breakage or chipping of the solid electrolyte layer during the manufacture of solid electrolyte sheets by roll-to-roll.

[0009] [2] A method for manufacturing a solid electrolyte sheet according to [1], wherein tension is applied to the three-dimensional structure.

[0010] According to the above embodiment, the three-dimensional structure can be transported with a force that does not cause the three-dimensional structure to break.

[0011] [3] The slurry is intermittently applied to one surface of the base material, The method for producing a solid electrolyte sheet according to [1], wherein the three-dimensional structure is fixed to a position on one surface of the base material where the slurry is not applied.

[0012] According to the above aspect, the rigidity of the solid electrolyte layer can be supplemented by stopping the conveyance of the base material and the three-dimensional structure and laminating the three-dimensional structure on one surface of the base material.

[0013] [4] The method for producing a solid electrolyte sheet according to [1], wherein the speed at which the three-dimensional structure starts to be fed to the surface of the coating film opposite to the base material is set to a low speed.

[0014] According to the above aspect, the three-dimensional structure can be arranged along one surface of the coating film made of the slurry.

[0015] [5] The method for producing a solid electrolyte sheet according to [1], wherein the three-dimensional structure is fixed to one surface of the base material with an adhesive tape before the application of the slurry is started.

[0016] According to the above aspect, the rigidity of the solid electrolyte layer can be supplemented. Therefore, in the production of the solid electrolyte sheet by Roll-to-Roll, breakage or chipping of the solid electrolyte layer can be suppressed.

[0017] [6] The method for producing a solid electrolyte sheet according to [1], wherein the three-dimensional structure is charged when the slurry is applied.

[0018] According to the above aspect, instead of the method of attaching a tape, the nonwoven fabric is thrown onto the coated surface of the slurry before drying, whereby an equivalent mixed state can be achieved without applying a tape.

[0019] [7] The method for producing a solid electrolyte sheet according to [1], wherein an angle formed by the surface of the coating film on the side opposite to the base material and the three-dimensional structure is an acute angle immediately before the coating film and the three-dimensional structure come into contact with each other.

[0020] According to the above aspect, the three-dimensional structure can be arranged along one surface of the coating film composed of the slurry.

[0021] [8] The method for producing a solid electrolyte sheet according to [1], wherein an angle formed by one surface of the base material and the three-dimensional structure is an acute angle immediately before the coating film and the three-dimensional structure come into contact with each other.

[0022] According to the above aspect, the three-dimensional structure can be arranged along one surface of the coating film composed of the slurry.

[0023] [9] The method for producing a solid electrolyte sheet according to [1], wherein the three-dimensional structure is a nonwoven fabric.

[0024] According to the above aspect, the insufficient rigidity of the solid electrolyte layer can be supplemented.

[0025]

[10] A solid electrolyte sheet filled with a solid electrolyte, the solid electrolyte sheet comprising: a sheet-shaped three-dimensional structure disposed at the center in the thickness direction and filled with the solid electrolyte inside; and solid electrolyte layers formed so as to cover the front surface and the back surface of the three-dimensional structure, respectively.

[0026] According to the above aspect, the three-dimensional structure supplements the rigidity of the solid electrolyte layer, and the solid electrolyte layer can be prevented from being broken or chipped.

[0027]

[11] The solid electrolyte sheet according to

[10] , wherein the three-dimensional structure is a nonwoven fabric.

[0028] According to the above aspect, the insufficient rigidity of the solid electrolyte layer can be supplemented. [Effects of the Invention]

[0029] According to the present invention, a method for manufacturing a solid electrolyte sheet reinforced with a three-dimensional structure, and a solid electrolyte sheet, can be provided in the production of a solid electrolyte sheet by roll-to-roll. [Brief explanation of the drawing]

[0030] [Figure 1] This is a schematic diagram showing a solid electrolyte sheet manufacturing apparatus used in a method for manufacturing a solid electrolyte sheet according to one embodiment of the present invention. [Figure 2] This is a cross-sectional view showing a solid electrolyte sheet according to one embodiment of the present invention. [Figure 3] This is a schematic diagram showing a solid electrolyte sheet manufacturing apparatus used in a method for manufacturing a solid electrolyte sheet according to one embodiment of the present invention. [Figure 4] This is a schematic diagram showing a solid electrolyte sheet manufacturing apparatus used in a method for manufacturing a solid electrolyte sheet according to one embodiment of the present invention. [Modes for carrying out the invention]

[0031] Embodiments of the present invention will be described below.

[0032] [Method for manufacturing solid electrolyte sheets] (First embodiment) Figure 1 is a schematic diagram showing a solid electrolyte sheet manufacturing apparatus used in the solid electrolyte sheet manufacturing method of this embodiment. Figure 2 is a cross-sectional view showing a solid electrolyte sheet manufactured by the solid electrolyte sheet manufacturing method of this embodiment. As shown in Figure 1, the solid electrolyte sheet manufacturing apparatus 100 of this embodiment is an apparatus that obtains a solid electrolyte sheet 10 filled with a solid electrolyte as shown in Figure 2 by forming a solid electrolyte layer 2 on one surface 1a of a substrate 1 that is conveyed by roll-to-roll using a three-dimensional structure 20 including a nonwoven fabric.

[0033] As shown in Figure 1, the solid electrolyte sheet manufacturing apparatus 100 of this embodiment includes a first substrate conveying roll 101, a second substrate conveying roll 102, a third substrate conveying roll 103, a first three-dimensional structure conveying roll 111, a second three-dimensional structure conveying roll 112, a coating apparatus 120, and a drying oven 130. The first substrate conveying roll 101 and the second three-dimensional structure conveying roll 112 are arranged to face each other via the substrate 1 and the three-dimensional structure 20.

[0034] The first substrate conveying roll 101, the second substrate conveying roll 102, and the third substrate conveying roll 103 are for conveying the substrate 1.

[0035] The first three-dimensional structure transport roll 111 and the second three-dimensional structure transport roll 112 are for transporting the three-dimensional structure 20.

[0036] The coating apparatus 120 is for coating one surface 1a of the substrate 1 with a slurry 30 containing a solid electrolyte.

[0037] The drying oven 130 is for drying a coating film 31 made of slurry 30 applied to one surface 1a of the substrate 1.

[0038] The method for manufacturing the solid electrolyte sheet of this embodiment will be described with reference to Figure 1. In this embodiment, before the application of the slurry 30 to one surface 1a of the substrate 1 begins, the three-dimensional structure 20 is fixed to one surface 1a of the substrate 1 with adhesive tape 40 (second step). The distance from the position on the substrate 1 where the three-dimensional structure 20 is fixed with adhesive tape 40 to the position where the application of the slurry 30 begins is preferably 1 m or more and 10 m or less.

[0039] The base material 1 is not particularly limited, but a sheet-like base material made of polyester such as polyethylene terephthalate can be used.

[0040] Next, the first substrate transport roll 101, the second substrate transport roll 102, the third substrate transport roll 103, etc. are driven to transport the substrate 1, and the first three-dimensional structure transport roll 111, the second three-dimensional structure transport roll 112, etc. are driven to transport the three-dimensional structure 20. As a result, the substrate 1 and the three-dimensional structure 20 are transported facing each other from positions opposite each other by the first substrate transport roll 101 and the second three-dimensional structure transport roll 112.

[0041] In transporting the three-dimensional structure 20, it is preferable to apply tension to the three-dimensional structure 20 by means other than transport rolls such as the first base material transport roll 101 and the second three-dimensional structure transport roll 112. As a device for applying tension to the three-dimensional structure 20, for example, a Permatork (magnetic brake), an electromagnetic brake, etc., can be used. A Permatork is a torque control device that utilizes the flow of magnetic field lines. By using a tension-applying device and controlling the tension applied to the three-dimensional structure 20, the three-dimensional structure 20 is transported together with the base material 1. This makes it possible to transport the three-dimensional structure 20 with a force that does not cause the three-dimensional structure 20 to break. The tension applied to the three-dimensional structure 20 by the tension-applying device is preferably 5N or more and 20N or less, and more preferably 8N or more and 10N or less. When the tension is within the above range, damage to the three-dimensional structure 20 can be suppressed.

[0042] Immediately before the coating film 31, which is made of slurry 30, comes into contact with the three-dimensional structure 20, it is preferable that the angle θ1 between the surface 31a of the coating film 31 opposite to the substrate 1 (hereinafter referred to as "one surface") and the three-dimensional structure 20 is acute, and preferably between 10° and 20°. By having an acute angle θ1, the three-dimensional structure 20 can be positioned along one surface 31a of the coating film 31.

[0043] Immediately before the coating film 31, which consists of slurry 30, comes into contact with the three-dimensional structure 20, the angle θ2 formed by one surface 1a of the substrate 1 and the three-dimensional structure 20 is preferably acute, and preferably between 20° and 30°. The acute angle θ2 allows the three-dimensional structure 20 to be positioned along one surface 1a of the substrate 1.

[0044] The speed at which the three-dimensional structure 20 is first fed onto one surface 31a of the coating film 31 is set to a low speed. Preferably, the speed at which the three-dimensional structure 20 is first fed is such that the three-dimensional structure 20 does not break. This allows the three-dimensional structure 20 to be positioned along one surface 31a of the coating film 31.

[0045] The three-dimensional structure 20 is not particularly limited as long as it can be stacked and arranged on one surface 1a of the base material 1 to supplement the rigidity of the coating film 31 and can be wound together with the base material 1, but it is preferably a nonwoven fabric. By using a nonwoven fabric, the nonwoven fabric is impregnated into the coating film 31, thereby compensating for the lack of rigidity in the coating film 31.

[0046] Next, as described above, the slurry 30 is applied to one side 1a of the substrate 1, which is being transported by roll-to-roll, using the coating device 120 (first step). As a result, a coating film 31 made of the slurry 30 is placed between the substrate 1 and the three-dimensional structure 20 at a position where the first substrate transport roll 101 and the second three-dimensional structure transport roll 112 are facing each other.

[0047] The amount of slurry 30 applied to one surface 1a of the substrate 1 (basis weight) is 2 mg / cm². 2 More than 10mg / cm 2 Preferably, it is 3 mg / cm³ 2 More than 5mg / cm 2 It is more preferable that the following conditions are met. When the basis weight is within the above range, it is possible to suppress the coating film 31 from breaking or chipping.

[0048] The slurry 30 is not particularly limited, but examples include one containing an oxide-based electrolyte or a sulfide-based electrolyte and a solvent. Additionally, the slurry 30 may contain other components such as a binder, as needed.

[0049] Next, the three-dimensional structure 20 is impregnated into the coating film 31 (second step).

[0050] Next, the coating film 31 is dried in a drying oven 130 to form a solid electrolyte layer 2 containing the three-dimensional structure 20, thereby obtaining a solid electrolyte sheet 10 filled with the solid electrolyte shown in Figure 2 (third step).

[0051] The temperature at which the coating film 31 is dried is preferably between 50°C and 150°C. When the temperature is within this range, cracking in the solid electrolyte layer 2 can be suppressed.

[0052] In the manufacturing method of the solid electrolyte sheet of this embodiment, the rigidity of the solid electrolyte layer 2 can be supplemented by fixing the three-dimensional structure 20 to one surface 1a of the substrate 1 with adhesive tape 40 before the start of coating of the slurry 30 to one surface 1a of the substrate 1. Therefore, it is possible to suppress breakage or chipping of the solid electrolyte layer 2 during the manufacturing of the solid electrolyte sheet by roll-to-roll. In addition, a solid electrolyte layer 2 having a predetermined shape and thickness can be formed on one surface 1a of the substrate 1.

[0053] As shown in Figure 2, the solid electrolyte sheet 10 comprises a base material 1, a solid electrolyte layer 2 formed on one surface 1a of the base material 1, and a three-dimensional structure 20 laminated on one surface 2a of the solid electrolyte layer 2. The three-dimensional structure 20 is partially or entirely impregnated with the solid electrolyte layer 2. In Figure 2, the solid electrolyte layer 2 is shown as an example where it is formed only on the surface (back surface) 20b of the three-dimensional structure 20 that faces the solid electrolyte layer 2, but the solid electrolyte sheet 10 of this embodiment is not limited to this. In the solid electrolyte sheet 10 of this embodiment, the solid electrolyte layer 2 may also be formed on the surface (front surface) 20a of the three-dimensional structure 20 opposite to the solid electrolyte layer 2.

[0054] According to the solid electrolyte sheet of this embodiment, the three-dimensional structure 20 reinforces the rigidity of the solid electrolyte layer 2, thereby preventing the solid electrolyte layer 2 from breaking or chipping.

[0055] (Second embodiment) Figure 3 is a schematic diagram showing a solid electrolyte sheet manufacturing apparatus used in the manufacturing method of the solid electrolyte sheet according to this embodiment. In Figure 3, components identical to those shown in Figure 1 are denoted by the same reference numerals and their descriptions are omitted. As shown in Figure 3, the solid electrolyte sheet manufacturing apparatus 200 of this embodiment is a manufacturing apparatus that obtains a solid electrolyte sheet 10 filled with the solid electrolyte shown in Figure 2 by forming a solid electrolyte layer 2 on one surface 1a of a substrate 1 that is conveyed by roll-to-roll using a three-dimensional structure 20 including a nonwoven fabric.

[0056] The method for manufacturing the solid electrolyte sheet of this embodiment will be described with reference to Figure 3. The base material 1 is transported by driving the first base material transport roll 101, the second base material transport roll 102, the third base material transport roll 103, etc.

[0057] Next, the slurry 30 is applied to one side 1a of the substrate 1, which is transported by roll-to-roll as described above, using the coating device 120 (first step).

[0058] The amount of slurry 30 applied to one surface 1a of the substrate 1 (basis weight) is 2 mg / cm². 2 More than 10mg / cm 2 Preferably, it is 3 mg / cm³ 2 More than 5mg / cm 2 It is more preferable that the following conditions are met. When the basis weight is within the above range, it is possible to suppress the coating film 31 from breaking or chipping.

[0059] After applying slurry 30 to one side 1a of the substrate 1, the transport of the substrate 1 is temporarily stopped.

[0060] Next, the first three-dimensional structure transport roll 111, the second three-dimensional structure transport roll 112, etc. are driven to transport the three-dimensional structure 20. Then, the base material 1 and the three-dimensional structure 20 are transported facing each other from positions opposite each other by the first base material transport roll 101 and the second three-dimensional structure transport roll 112.

[0061] In transporting the three-dimensional structure 20, it is preferable to apply tension to the three-dimensional structure 20 by means other than transport rolls, such as the first base material transport roll 101 and the second three-dimensional structure transport roll 112. The device for applying tension to the three-dimensional structure 20 is the same as in the first embodiment. The tension applied to the three-dimensional structure 20 by the tension-applying device is preferably 5N or more and 20N or less, and more preferably 8N or more and 10N or less. When the tension is within the above range, damage to the three-dimensional structure 20 can be suppressed.

[0062] Immediately before the coating film 31, which is made of slurry 30, comes into contact with the three-dimensional structure 20, it is preferable that the angle θ11 between the surface 31a of the coating film 31 opposite to the substrate 1 (hereinafter referred to as "one surface") and the three-dimensional structure 20 is acute, and preferably between 10° and 20°. By having an acute angle θ11, the three-dimensional structure 20 can be positioned along one surface 31a of the coating film 31.

[0063] Immediately before the coating film 31, which is made of slurry 30, comes into contact with the three-dimensional structure 20, the angle θ12 formed by one surface 1a of the substrate 1 and the three-dimensional structure 20 is preferably acute, and preferably between 20° and 30°. The acute angle θ12 allows the three-dimensional structure 20 to be positioned along one surface 1a of the substrate 1.

[0064] The speed at which the three-dimensional structure 20 is first fed onto one surface 31a of the coating film 31 is set to a low speed. This allows the three-dimensional structure 20 to be positioned along one surface 31a of the coating film 31.

[0065] The three-dimensional structure 20 is preferably made of a nonwoven fabric. By using a nonwoven fabric, the nonwoven fabric is impregnated into the coating film 31, thereby compensating for the lack of rigidity in the coating film 31.

[0066] Next, the transport of the three-dimensional structure 20 is stopped, and the three-dimensional structure 20 is fixed to one surface 1a of the base material 1 with adhesive tape 41. This impregnates the three-dimensional structure 20 with the coating film 31 (second step). For example, the position where the three-dimensional structure 20 is fixed to one surface 1a of the base material 1 with adhesive tape 41 is near the second base material transport roll 102, and a position where the coating film 31 made of slurry 30 has not yet been formed. Then, at the position where the first base material transport roll 101 and the second three-dimensional structure transport roll 112 face each other, the coating film 31 made of slurry 30 is placed between the base material 1 and the three-dimensional structure 20.

[0067] Next, after the three-dimensional structure 20 has been fixed to one surface 1a of the substrate 1 using the adhesive tape 41, the coating of the slurry 30 to one surface 1a of the substrate 1 by the coating apparatus 120 is resumed.

[0068] Next, the coating film 31 is dried in a drying oven 130 to form a solid electrolyte layer 2 containing the three-dimensional structure 20, thereby obtaining a solid electrolyte sheet 10 filled with the solid electrolyte shown in Figure 2 (third step).

[0069] The temperature at which the coating film 31 is dried is preferably between 50°C and 150°C. When the temperature is within this range, cracking in the solid electrolyte layer 2 can be suppressed.

[0070] In the manufacturing method for solid electrolyte sheets of this embodiment, the rigidity of the solid electrolyte layer 2 can be supplemented by stopping the transport of the base material 1 and the three-dimensional structure 20 and fixing the three-dimensional structure 20 to one surface 1a of the base material 1 with adhesive tape 41. Therefore, it is possible to suppress damage or chipping of the solid electrolyte layer 2 during the manufacturing of solid electrolyte sheets by roll-to-roll. In addition, a solid electrolyte layer 2 having a predetermined shape and thickness can be formed on one surface 1a of the base material 1.

[0071] (Third Embodiment) Figure 4 is a schematic diagram showing a solid electrolyte sheet manufacturing apparatus used in the method for manufacturing a solid electrolyte sheet of the present embodiment. In Figure 4, the same constituent elements as those shown in Figure 1 are denoted by the same reference numerals, and descriptions thereof are omitted. As shown in Figure 4, the solid electrolyte sheet manufacturing apparatus 300 of the present embodiment is a manufacturing apparatus that forms the solid electrolyte layer 2 on one surface 1a of the base material 1 conveyed by Roll-to-Roll using the three-dimensional structure 20 containing a nonwoven fabric, thereby obtaining the solid electrolyte sheet 10 filled with the solid electrolyte shown in Figure 2.

[0072] As shown in Figure 4, the solid electrolyte sheet manufacturing apparatus 300 of the present embodiment includes a first base material conveying roll 101, a second base material conveying roll 102, a third base material conveying roll 103, a first three-dimensional structure conveying roll 111, a second three-dimensional structure conveying roll 112, a coating device 120, a drying furnace 130, and a three-dimensional structure loading mechanism 310.

[0073] The three-dimensional structure loading mechanism 310 is for laminating the three-dimensional structure 20 on one surface 31a of the coating film 31.

[0074] The method for manufacturing the solid electrolyte sheet of the present embodiment will be described with reference to Figure 4. The first base material conveying roll 101, the second base material conveying roll 102, the third base material conveying roll 103, and the like are driven to convey the base material 1.

[0075] Next, the slurry 30 is applied by the coating device 120 to one surface 1a of the base material 1 conveyed by Roll-to-Roll as described above (first step).

[0076] The coating amount (basis weight) of the slurry 30 applied to one surface 1a of the base material 1 is 2 mg / cm 2 or more and 10 mg / cm 2 or less, more preferably 3 mg / cm 2 or more and 5 mg / cm 2It is more preferable that the following conditions are met. When the basis weight is within the above range, it is possible to suppress the coating film 31 from breaking or chipping.

[0077] Next, the first three-dimensional structure transport roll 111, the second three-dimensional structure transport roll 112, etc., are driven to transport the three-dimensional structure 20. Then, the base material 1 and the three-dimensional structure 20 are transported facing each other from positions opposite each other, such as the first base material transport roll 101 and the second three-dimensional structure transport roll 112. At the start of transporting the base material 1 and the three-dimensional structure 20, the base material 1 and the three-dimensional structure 20 are separated, and there is a gap between the base material 1 and the three-dimensional structure 20.

[0078] In transporting the three-dimensional structure 20, it is preferable to apply tension to the three-dimensional structure 20 by means other than transport rolls, such as the first base material transport roll 101 and the second three-dimensional structure transport roll 112. The device for applying tension to the three-dimensional structure 20 is the same as in the first embodiment. The tension applied to the three-dimensional structure 20 by the tension-applying device is preferably 5N or more and 20N or less, and more preferably 8N or more and 10N or less. When the tension is within the above range, damage to the three-dimensional structure 20 can be suppressed.

[0079] Immediately before the coating film 31, which is made of slurry 30, comes into contact with the three-dimensional structure 20, it is preferable that the angle θ21 between the surface 31a of the coating film 31 opposite to the substrate 1 (hereinafter referred to as "one surface") and the three-dimensional structure 20 is acute, and preferably between 10° and 20°. By having an acute angle θ21, the three-dimensional structure 20 can be positioned along one surface 31a of the coating film 31.

[0080] Immediately before the coating film 31, which consists of slurry 30, comes into contact with the three-dimensional structure 20, the angle θ22 formed by one surface 1a of the substrate 1 and the three-dimensional structure 20 is preferably acute, and preferably between 20° and 30°. The acute angle θ22 allows the three-dimensional structure 20 to be positioned along one surface 1a of the substrate 1.

[0081] The speed at which the three-dimensional structure 20 is first fed onto one surface 31a of the coating film 31 is set to a low speed. This allows the three-dimensional structure 20 to be positioned along one surface 31a of the coating film 31.

[0082] The three-dimensional structure 20 is preferably made of a nonwoven fabric. By using a nonwoven fabric, the nonwoven fabric is impregnated into the coating film 31, thereby compensating for the lack of rigidity in the coating film 31.

[0083] Next, the three-dimensional structure loading mechanism 310 loads the three-dimensional structure 20 onto one surface 31a of the coating film 31 formed on the substrate 1 being transported by the first substrate transport roll 101, the second three-dimensional structure transport roll 112, etc. Specifically, the three-dimensional structure loading mechanism 310 brings the three-dimensional structure 20 into contact with one surface 31a of the coating film 31, thereby loading the three-dimensional structure 20 onto one surface 31a of the coating film 31. As a result, the coating film 31 is positioned between the substrate 1 and the three-dimensional structure 20 at a position where the second substrate transport roll 102 and the three-dimensional structure loading mechanism 310 face each other. This impregnates the coating film 31 with the three-dimensional structure 20 (second step).

[0084] Next, the coating film 31 is dried in a drying oven 130 to form a solid electrolyte layer 2 containing the three-dimensional structure 20, thereby obtaining a solid electrolyte sheet 10 filled with the solid electrolyte shown in Figure 2 (third step).

[0085] The temperature at which the coating film 31 is dried is preferably between 50°C and 150°C. When the temperature is within this range, cracking in the solid electrolyte layer 2 can be suppressed.

[0086] In the manufacturing method of the solid electrolyte sheet of this embodiment, a three-dimensional structure 20 is laminated onto one surface 31a of the coating film 31 formed on the transported substrate 1. This reinforces the rigidity of the solid electrolyte layer 2. Therefore, it is possible to suppress breakage or chipping of the solid electrolyte layer 2 during the manufacturing of the solid electrolyte sheet by roll-to-roll. Furthermore, a solid electrolyte layer 2 having a predetermined shape and thickness can be formed on one surface 1a of the substrate 1.

[0087] (Fourth embodiment) In this embodiment, as in the third embodiment, the solid electrolyte sheet manufacturing apparatus shown in Figure 4 is used.

[0088] The method for manufacturing the solid electrolyte sheet of this embodiment will be described with reference to Figure 4. The base material 1 is transported by driving the first base material transport roll 101, the second base material transport roll 102, the third base material transport roll 103, etc.

[0089] Next, the slurry 30 is applied to one side 1a of the substrate 1, which is transported by roll-to-roll as described above, using the coating device 120 (first step).

[0090] The amount of slurry 30 applied to one surface 1a of the substrate 1 (basis weight) is 2 mg / cm². 2 More than 10mg / cm 2 Preferably, it is 3 mg / cm³ 2 More than 5mg / cm 2 It is more preferable that the following conditions are met. When the basis weight is within the above range, it is possible to suppress the coating film 31 from breaking or chipping.

[0091] After applying slurry 30 to one side 1a of the substrate 1, the transport of the substrate 1 is temporarily stopped.

[0092] Next, the first three-dimensional structure transport roll 111, the second three-dimensional structure transport roll 112, etc., are driven to transport the three-dimensional structure 20. Then, the base material 1 and the three-dimensional structure 20 are transported facing each other from positions opposite each other, such as the first base material transport roll 101 and the second three-dimensional structure transport roll 112. At the start of transporting the base material 1 and the three-dimensional structure 20, the base material 1 and the three-dimensional structure 20 are separated, and there is a gap between the base material 1 and the three-dimensional structure 20.

[0093] In transporting the three-dimensional structure 20, it is preferable to apply tension to the three-dimensional structure 20 by means other than transport rolls, such as the first base material transport roll 101 and the second three-dimensional structure transport roll 112. The device for applying tension to the three-dimensional structure 20 is the same as in the first embodiment. The tension applied to the three-dimensional structure 20 by the tension-applying device is preferably 5N or more and 20N or less, and more preferably 8N or more and 10N or less. When the tension is within the above range, damage to the three-dimensional structure 20 can be suppressed.

[0094] Immediately before the coating film 31, which is made of slurry 30, comes into contact with the three-dimensional structure 20, it is preferable that the angle θ21 between the surface 31a of the coating film 31 opposite to the substrate 1 (hereinafter referred to as "one surface") and the three-dimensional structure 20 is acute, and preferably between 10° and 20°. By having an acute angle θ21, the three-dimensional structure 20 can be positioned along one surface 31a of the coating film 31.

[0095] Immediately before the coating film 31, which consists of slurry 30, comes into contact with the three-dimensional structure 20, the angle θ22 formed by one surface 1a of the substrate 1 and the three-dimensional structure 20 is preferably acute, and preferably between 20° and 30°. The acute angle θ22 allows the three-dimensional structure 20 to be positioned along one surface 1a of the substrate 1.

[0096] The speed at which the three-dimensional structure 20 is first fed onto one surface 31a of the coating film 31 is set to a low speed. This allows the three-dimensional structure 20 to be positioned along one surface 31a of the coating film 31.

[0097] The three-dimensional structure 20 is preferably made of a nonwoven fabric. By using a nonwoven fabric, the nonwoven fabric is impregnated into the coating film 31, thereby compensating for the lack of rigidity in the coating film 31.

[0098] Next, the transport of the three-dimensional structure 20 is stopped, and the three-dimensional structure input mechanism 310 stacks the three-dimensional structure 20 onto one surface 31a of the coating film 31 formed on the substrate 1. Specifically, the three-dimensional structure input mechanism 310 brings the three-dimensional structure 20 into contact with one surface 31a of the coating film 31, thereby stacking the three-dimensional structure 20 onto one surface 31a of the coating film 31. As a result, the coating film 31 is positioned between the substrate 1 and the three-dimensional structure 20 at a position where the second substrate transport roll 102 and the three-dimensional structure input mechanism 310 are facing each other. This impregnates the coating film 31 with the three-dimensional structure 20 (second step).

[0099] Next, after the lamination of the three-dimensional structure 20 onto one surface 31a of the coating film 31 by the three-dimensional structure input mechanism 310 is completed, the coating of the slurry 30 onto one surface 1a of the substrate 1 by the coating apparatus 120 is resumed.

[0100] Next, the coating film 31 is dried in a drying oven 130 to form a solid electrolyte layer 2 containing the three-dimensional structure 20, thereby obtaining a solid electrolyte sheet 10 filled with the solid electrolyte shown in Figure 2 (third step).

[0101] The temperature at which the coating film 31 is dried is preferably between 50°C and 150°C. When the temperature is within this range, cracking in the solid electrolyte layer 2 can be suppressed.

[0102] According to the manufacturing method of the solid electrolyte sheet of this embodiment, the rigidity of the solid electrolyte layer 2 can be supplemented by stopping the transport of the base material 1 and the three-dimensional structure 20 and laminating the three-dimensional structure 20 onto one surface 1a of the base material 1 using the three-dimensional structure input mechanism 310. Therefore, it is possible to suppress damage or chipping of the solid electrolyte layer 2 during the manufacturing of the solid electrolyte sheet by roll-to-roll. In addition, a solid electrolyte layer 2 having a predetermined shape and thickness can be formed on one surface 1a of the base material 1.

[0103] Although embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various modifications and changes are possible within the scope of the gist of the present invention as described in the claims. [Examples]

[0104] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0105] [Example 1] A solid electrolyte sheet was manufactured in the same manner as in the first embodiment described above. The transport speed for the base material and nonwoven fabric was set to 10 m / min. The slurry used contained alumina and an organic solvent to disperse the alumina. The tension applied to the nonwoven fabric was set to 9N. The distance from the position where the three-dimensional structure is fixed to the substrate with adhesive tape to the position where slurry coating begins, i.e., the distance over which the substrate is transported without slurry coating (uncoated transport distance), was set to 1m, 5m, or 10m. The drying temperature for the three-dimensional structure and the coating film was set to 100°C or 120°C. Under each of the conditions shown in Table 1, the presence or absence of wrinkles in the substrate was visually inspected when manufacturing solid electrolyte sheets. The results are shown in Table 1.

[0106] [Table 1]

[0107] The results shown in Table 1 confirm that no wrinkles occurred on the substrate in any of the tests No. #1 to #6.

[0108] [Example 2] A solid electrolyte sheet was manufactured in the same manner as in the fourth embodiment described above. The transport speed for the base material and nonwoven fabric was set to 10 m / min. The slurry used contained alumina and an organic solvent to disperse the alumina. The tension applied to the nonwoven fabric was set to 9N. The drying temperature for the three-dimensional structure and the coating film was set to 100°C or 120°C. When a solid electrolyte sheet was manufactured under the conditions shown in Table 2, we visually checked whether wrinkles formed on the substrate when the nonwoven fabric was laid on one side of a slurry coating film using a three-dimensional structure feeding mechanism while the nonwoven fabric was stretched (throw-in method shown in Table 2), and when the nonwoven fabric was laid on one side of a slurry coating film using a three-dimensional structure feeding mechanism while the nonwoven fabric was rolled up (ball-forming throw-in method shown in Table 2). The results are shown in Table 2.

[0109] [Table 2]

[0110] The results shown in Table 2 confirm that no wrinkles occur on the substrate in either the throw-in method or the ball-forming throw-in method. [Explanation of Symbols]

[0111] 1 Base material 2 Solid electrolyte layer 10 Solid Electrolyte Sheets 20 Three-dimensional structure 30 Slurry 31 Coating 40, 41 Adhesive tape 101 First substrate conveying roll 102 Second substrate transport roll 103 Third substrate transport roll 111 First three-dimensional structure transport roll 112 Second Three-Dimensional Structure Transport Roll 120 Coating equipment 130 Drying oven Manufacturing equipment for 100, 200, and 300 solid electrolyte sheets 310 Three-dimensional structure loading mechanism

Claims

1. A method for manufacturing a solid electrolyte sheet filled with a solid electrolyte, A first step involves coating one side of a substrate being transported by roll-to-roll with a slurry containing a solid electrolyte, A second step involves impregnating the coating film, which consists of the slurry, with a three-dimensional structure including a nonwoven fabric. A method for manufacturing a solid electrolyte sheet, comprising: a third step of drying the coating film to form a solid electrolyte layer including the three-dimensional structure, thereby obtaining a solid electrolyte sheet filled with a solid electrolyte.

2. A method for manufacturing a solid electrolyte sheet according to claim 1, wherein tension is applied to the three-dimensional structure.

3. A method for manufacturing a solid electrolyte sheet according to claim 1, comprising intermittently coating the slurry onto one surface of the substrate and fixing the three-dimensional structure to a position on one surface of the substrate where the slurry has not been coated.

4. The method for manufacturing a solid electrolyte sheet according to claim 1, wherein the speed at which the three-dimensional structure is fed to the side of the coating film opposite to the substrate is set to be low.

5. The method for manufacturing a solid electrolyte sheet according to claim 1, wherein the three-dimensional structure is fixed to one side of the substrate with adhesive tape before the start of coating the slurry.

6. A method for manufacturing a solid electrolyte sheet according to claim 1, wherein the three-dimensional structure is introduced when coating the slurry.

7. The method for manufacturing a solid electrolyte sheet according to claim 1, wherein, immediately before the coating film and the three-dimensional structure come into contact, the angle between the surface of the coating film opposite to the substrate and the three-dimensional structure is acute.

8. The method for manufacturing a solid electrolyte sheet according to claim 1, wherein, immediately before the coating film and the three-dimensional structure come into contact, the angle between one surface of the substrate and the three-dimensional structure is acute.

9. The method for producing a solid electrolyte sheet according to claim 1, wherein the three-dimensional structure is a nonwoven fabric.

10. A solid electrolyte sheet filled with a solid electrolyte, A sheet-like three-dimensional structure positioned in the center in the thickness direction, with a solid electrolyte filling the interior, A solid electrolyte sheet comprising a solid electrolyte layer formed to cover the front and back surfaces of the three-dimensional structure, respectively.

11. The solid electrolyte sheet according to claim 10, wherein the three-dimensional structure is a nonwoven fabric.

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