JP2014127260A - Method of manufacturing solid electrolyte battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a stacked solid electrolyte battery, by which a short circuit between collectors is prevented during manufacturing and a battery structure efficiently stacked as a stacked battery is obtained.SOLUTION: In a method of manufacturing a solid electrolyte battery, a laminate is cut by the engagement of two cutting blades disposed on a positive electrode side and a negative electrode side to obtain a battery structure, the laminate including at least a positive electrode, a solid electrolyte and a negative electrode between first and second collector foils. In the method, blade surfaces of the two cutting blades are brought into contact each other in an electrolyte layer.

Description

  The present invention relates to a method for manufacturing a solid electrolyte battery in which a battery structural member having at least a solid electrolyte and an electrode is laminated between current collecting foils.

  In recent years, the demand for stacked batteries has increased, and a method for efficiently manufacturing a large number of stacked batteries in a short time is required. As a method for efficiently manufacturing a laminated battery, a thin, strip-shaped covering in which a battery structure composed of a positive electrode, an electrolyte, a negative electrode, and an insulator covering these electrodes and the electrolyte is continuously formed between current collectors. A method of obtaining a battery structure laminated on a laminated battery by manufacturing a cut body and lowering a cutting blade on the cut body has been considered.

  However, when cutting the object to be cut, one of the current collector foils that is cut first may be bent and deformed by receiving a pressing force from the cutting blade. When the cutting blade is further lowered in a state where one of the current collector foils is bent and deformed, the bent portion of the one current collector foil and the other current collector foil may come into contact with each other, thereby causing a short circuit.

  Here, as a method for preventing a short circuit in the laminated battery at the time of cutting with a cutting blade, a method is disclosed in which the current collector foil is temporarily cut prior to the main cutting and an insulating treatment is performed on the temporarily cut surface. (For example, refer to Patent Document 1).

JP 2008-053103 A

  However, in the method of Patent Document 1, there is a risk that a short circuit occurs between the positive electrode and the negative electrode due to end deformation.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a stacked solid electrolyte battery that prevents a short circuit between current collectors during manufacturing and obtains a battery structure that is efficiently stacked on a stacked battery.

  In order to solve the above problems, according to the present invention, a laminate having at least a positive electrode, a solid electrolyte, and a negative electrode is disposed between the first and second current collector foils on the positive electrode side and the negative electrode side. A method for manufacturing a solid electrolyte battery, wherein the battery structure is obtained by cutting by engaging two cutting blades, wherein the blade surfaces of the two cutting blades are in contact with each other in the electrolyte layer. Provided.

  Prior to cutting with the cutting blade, it is preferable to cut the current collector foil using a laser.

  According to the present invention, since the blade surfaces of the two cutting blades are in contact with each other in the electrolyte layer when the object to be cut is cut, it is possible to reduce the risk that the current collector foils are in contact with each other and short-circuited. .

It is the schematic of the manufacturing process of the solid electrolyte battery of this invention. It is an enlarged view in the stop position T8 of the manufacturing process of FIG. It is the schematic of the process of cut | disconnecting current collection foil with a laser beam.

  The present invention will be described below with reference to the drawings. Here, a method for manufacturing a bipolar battery as a stacked battery will be described. Here, FIG. 1 is a schematic view of a manufacturing process for effectively carrying out the bipolar battery manufacturing method of the present embodiment. In FIG. 1, for ease of explanation, the negative electrode layer 13, the solid electrolyte layer 14, and the positive electrode layer 15 in the continuous battery structure 1 are shown exposed (cross-sectional view). Covered with insulating material.

  The schematic structure of the bipolar battery manufacturing method of this example is that a negative electrode layer 13, a solid electrolyte layer 14, and a positive electrode layer 15 are laminated between current collector foils (current collectors) 11, 12, and these laminated bodies. A continuous battery structure (a body to be cut) 1 in which a battery structure 2 whose periphery is covered with an insulating layer 6 is continuously formed in the plane direction of the current collector foils 11 and 12 is formed at a predetermined position (region where the insulating layer 6 is formed ) To obtain a battery structure 2 to be stacked on the bipolar battery, and is characterized by cutting the continuous battery structure 1 with two cutting blades 37 and 38.

  In FIG. 1, the current collector foil 11 is wound around the current collector foil supply roller 23, and the current collector foil 11 sent out from the current collector foil supply roller 23 is guided by the guide roller 24 while being conveyed by the conveyor 25. It enters the conveying surface of (conveying means) and is conveyed in the direction of arrow X. The conveyance conveyor 25 is an endless rotation type belt conveyor, and driving / stopping is controlled by a conveyance operation control circuit (not shown).

  T1 to T8 in FIG. 1 indicate the stop position of the insulating layer 6 formed on the current collector foil 11, and the transport operation control circuit stops the insulating layer 6 at the stop positions T1 to T8 for a predetermined time. Thus, the conveyor 25 is intermittently driven. The intervals between adjacent stop positions are all set to be the same. Examples of the material of the current collector foil 11 include aluminum foil, stainless steel foil, and copper foil.

(Step S101)
At the stop position T1, a first insulating material supply unit 31 configured by an ink jet head is provided, and the insulating material sprayed from the first insulating material supply unit 31 is viewed on the current collector foil 11 in plan view. A rectangular lower insulating layer 6a is formed. Here, examples of the material used for the lower insulating layer 6a include polyethylene, polycello, polypropylene, coated polyester, nylon, coated polypropylene, polystyrene, polyvinyl alcohol, polycarbonate, polyvinylidene chloride, and polyimide. The same material as that of the lower insulating layer 6a can be used for the middle insulating layer 6b and the upper insulating layer 6c described later. Further, the lower insulating layer 6a may be formed by spray printing, electrostatic spraying, or sputtering instead of the ink jet method by the first insulating material supply unit 31.

(Step S102)
The stop position T2 is provided with a second insulating material supply unit 32 composed of an inkjet head, and is rectangular in plan view on the lower insulating layer 6a by the insulating material sprayed from the second insulating material supply unit 32. The middle insulating layer 6b is formed. Here, the middle insulating layer 6b is set to have a dimension in the arrow X direction smaller than that of the lower insulating layer 6a. The regions on both the left and right sides (in the arrow X direction) on the upper surface of the lower insulating layer 6a The middle insulating layer non-formation region 61a is not formed. Note that the middle insulating layer 6a may be formed by spray printing, electrostatic spraying, or sputtering instead of the ink jet method by the second insulating material supply unit 32.

(Step S103)
Between the stop positions T2 and T3, a positive electrode layer supply unit 33 constituted by an ink jet head is provided so as to be able to reciprocate in the direction of the arrow X1, and depending on the positive electrode layer material injected from the positive electrode layer supply unit 33, A positive electrode layer 15 having a rectangular shape in plan view is formed on the current collector foil 11 between the lower insulating layers 6a stopped at the stop positions T2 and T3. Here, examples of the positive electrode active material used for the positive electrode layer 15 include spinel LiMn ₂ O ₄ , and a composite oxide of transition metal and lithium used in a solution-type lithium ion battery. Specifically, Li · Co-based composite oxide such as LiCoO _2, Li · Ni-based composite oxide such as LiNiO _2, Li · Mn-based composite oxide such as spinel LiMn ₂ O _4, Li · such LiFeO ₂ Examples thereof include Fe-based composite oxides. In addition, transition metal and lithium phosphate compounds and sulfate compounds such as LiFePO ₄ ; transition metal oxides and sulfides such as V ₂ O ₅ , MnO ₂ , TiS ₂ , MoS ₂ , and MoO ₃ ; PbO ₂ , AgO, NiOOH or the like can also be used. Moreover, you may mix a polymer, a polymerization initiator, a conductive support agent, and a solvent with a positive electrode active material. Note that the positive electrode layer 15 may be formed by spray printing, electrostatic spraying, or sputtering instead of the ink jet method by the positive electrode layer supply unit 33.

(Step S104)
Between the stop positions T3 and T4, an electrolyte layer supply unit 34 constituted by an inkjet head is provided so as to be able to reciprocate in the direction of the arrow X2, and by the electrolyte material injected from the electrolyte layer supply unit 34, The solid electrolyte layer 14 having a rectangular shape in plan view is formed on the middle insulating layer non-formation region 61a and the positive electrode layer 15 which are stopped at the stop positions T3 and T4, respectively. Here, examples of the ion conductive material of the solid electrolyte layer 14 include polyethylene oxide and polypropylene oxide. A viscous binder may be mixed with the powdered ion conductive material. Examples of the viscous binder include polyvinyl alcohol (PVA), methyl cellulose, nitrocellulose, and ethyl cellulose. Thus, the intensity | strength of the solid electrolyte layer 14 can be increased by mixing a viscous binder. Note that the solid electrolyte layer 14 may be formed using spray printing, electrostatic spraying, or sputtering instead of the ink jet method using the electrolyte layer supply unit 34.

(Step S105)
At the stop position T5, a third insulating material supply unit 35 constituted by an ink jet head is provided, and the insulating material sprayed from the third insulating material supply unit 35 is rectangular on the middle insulating layer 6b in plan view. An upper insulating layer 6c having a shape is formed. Here, the dimension of the upper insulating layer 6c in the arrow X direction is larger than that of the middle insulating layer 6b and is set to be the same as that of the lower insulating layer 6a. Therefore, the upper insulating layer 6c is also partially formed on the stationary electrolyte layer 14 that is stopped between the stop positions T4 and T5 and between the stop positions T5 and T6. Note that the upper insulating layer 6c may be formed using spray printing, electrostatic spraying, or sputtering instead of the ink jet method using the third insulating material supply unit 35.

(Step S106)
Between the stop positions T5 and T6, a negative electrode layer supply unit 36 composed of an inkjet head is provided so as to be reciprocally movable in the direction of arrow X3. The negative electrode layer material injected from the negative electrode layer supply unit 36 The negative electrode layer 13 is formed on the solid electrolyte layer 14 between the upper insulating layers 6c stopped at the stop positions T2 and T3. Here, examples of the negative electrode active material constituting the negative electrode layer 13 include transition metal oxides, composite oxides of transition metals and lithium, oxides of titanium, and composite oxides of titanium and lithium. Alternatively, the negative electrode active material may be mixed with a polymer, a polymerization initiator, a conductive additive, and a solvent to form a material for the negative electrode layer 13. Note that the negative electrode layer 13 may be formed using spray printing, electrostatic spraying, or sputtering instead of the ink jet method using the negative electrode layer supply unit 36.

(Step S107)
Between the stop positions T6 and T7, a current collector foil supply roller 26 around which the current collector foil 12 is wound is provided. The current collector foil 12 fed from the current collector foil supply roller 26 is provided with a guide roller 27. Is supplied onto the negative electrode layer 13 and the upper insulating layer 6c. The current collector foil 12 is supplied onto the negative electrode layer 13 and the upper insulating layer 6c, whereby the continuous battery structure 1 is manufactured. The continuous battery structure 1 moves from the stop position T6 to T7, and the pressing roller 28 is moved. , 29 is pressed. The material of the current collector foil 12 is the same as that of the current collector foil 11.

(Step S108)
At the stop position T8, a cutting unit 21 that performs cutting for separating the battery structure 2 from the continuous battery structure 1 is provided. The cutting unit 21 is lifted and lowered when the two cutting blades 37 and 38 are driven up and down by a lifting device (not shown) and the continuous battery structure 1 is stopped (the conveyor 25 is stopped). The battery structure 1 is cut.

  Here, the cutting | disconnection of the continuous battery structure 1 by two cutting blades is demonstrated in detail in FIG. When the continuous battery structure 1 is stopped at the stop position T8, the two cutting blades 37 and 38 are lifted and lowered to engage with each other, and the continuous battery structure 1 is cut. At this time, the two cutting blades 37 and 38 are controlled so that the blade surfaces come into contact with each other in the electrolyte layer 14. In FIG. 1, the cutting is performed at only one location of the continuous battery structure 1, but as shown in FIG. 2, the upper and lower surfaces of the continuous battery structure 1 are supported by the holding jig 39 and cut from both sides. Also good.

  Before performing cutting with this cutting blade, it is preferable to cut only the current collector foils 11 and 12 with a laser beam 40 and then cut with the cutting blades 37 and 38 as described above, as shown in FIG. . Here, when the metallic current collector foil is melted with a high-energy laser beam, the melted metal part becomes agglomerated and may cause a short circuit depending on the battery structure. It is preferable to cut. As the laser light, it is preferable to use a carbon dioxide gas laser or a YAG laser that has a high absorption coefficient with respect to metal foil and ceramic (active material, electrolyte) and can achieve high output. As described above, the current collector foil is cut in advance with the laser beam which is difficult to deform the electrode end portion, so that the short circuit can be surely prevented.

  Finally, the end portion of the continuous battery structure 1 is insulated with an insulating material, for example, a resin used for the lower insulating layer 6a. Then, the cut battery structures 2 are sequentially stacked and pressed by a pressing device (not shown) to manufacture a bipolar battery.

  In the above embodiment, the current collector foils 11 and 12 are made of the same metal. However, the present invention can also be applied to a non-bipolar stacked battery in which the current collector foils 11 and 12 are made of different metals. . Also, a method of cutting a continuous battery structure (a body to be cut) in which the insulating layer 6 is not provided and the negative electrode layer 13, the solid electrolyte layer 14, and the positive electrode layer 15 are continuously formed between the current collector foils 11 and 12 at a predetermined position. The present invention can also be applied. In this case, it is preferable to cover the negative electrode layer 13, the solid electrolyte layer 14, and the positive electrode layer 15 with an insulating layer after cutting. Furthermore, although the continuous battery structure 1 is cut | disconnected in an Example, the method of this invention can be used also when cutting to the desired battery size of a battery design from the battery structure of medium size and a large sized size. it can.

DESCRIPTION OF SYMBOLS 1 Continuous battery structure 2 Battery structure 6 Insulating layer T1-T9 Stop position 11, 12 Current collecting foil 13 Negative electrode layer 14 Solid electrolyte layer 15 Positive electrode layer 21 Cutting part 23, 26 Current collecting foil supply roller 24, 27 Guide roller 25 Conveyor 28, 29 Press roller 31 First insulating material supply unit 32 Second insulating material supply unit 33 Positive electrode layer supply unit 34 Electrolyte layer supply unit 35 Third insulating material supply unit 36 Negative electrode layer supply unit 37, 38 Cutting Blade 39 Holding jig 40 Laser light

Claims (2)

  A battery structure in which a laminate having at least a positive electrode, a solid electrolyte, and a negative electrode between the first and second current collector foils is cut by meshing two cutting blades disposed on the positive electrode side and the negative electrode side. A manufacturing method of a solid electrolyte battery, wherein the blade surfaces of the two cutting blades are in contact with each other in the electrolyte layer.   The method according to claim 1, wherein the current collector foil is cut with a laser prior to cutting with the cutting blade.

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