JP2020017478A - Method for manufacturing all-solid battery and all-solid battery - Google Patents

Abstract

To provide a method for manufacturing an all-solid battery in which a positive electrode layer and a negative electrode layer surely contain a gel electrolyte, and the all-solid battery.SOLUTION: A method for manufacturing an all-solid battery according to an embodiment comprises the steps of: applying a first coating liquid containing a first ionic liquid, a first gelatinizer, a first binder and a positive electrode active material to a first principal face of a first current collector and then, gelatinizing the first ionic liquid by the first gelatinizer and solidifying the first coating liquid by the first binder, thereby forming a first electrode having the first current collector with a positive electrode layer disposed thereon; applying a second coating liquid containing a second ionic liquid, a second gelatinizer, a second binder and a negative electrode active material to a second principal face of a second current collector and then, gelatinizing the second ionic liquid by the second gelatinizer and solidifying the second coating liquid by the second binder, thereby forming a second electrode having the second current collector with a negative electrode layer disposed thereon; and laminating the first and second electrodes in one direction so that they are located on opposing sides of a separator containing a solid or gel electrolyte, thereby forming an electrode laminate.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an all-solid-state battery manufacturing method and an all-solid-state battery.

  An example of a power storage device is an all-solid-state battery. Patent Document 1 listed below discloses an embodiment in which a plurality of stacked batteries (power storage cells) are stacked via a positive electrode current collector foil and a negative electrode current collector foil. These stacked batteries are connected in parallel with each other and are sealed with a mold resin. The laminated battery is configured by laminating a positive electrode layer, a solid electrolyte layer, and a negative electrode layer.

JP 2014-116156 A

  In the all-solid-state battery as described in Patent Document 1, the electrolyte is also contained in the positive electrode layer and the negative electrode layer. As a method of including an electrolyte in such a positive electrode layer and a negative electrode layer, for example, it is conceivable that, once a positive electrode layer and a negative electrode layer containing no electrolyte are once formed, a gel electrolyte is impregnated in the positive electrode layer and the negative electrode layer. . However, when the high-viscosity gel electrolyte is impregnated into the positive electrode layer and the negative electrode layer in order to form an all-solid battery, only the liquid portion of the gel electrolyte is impregnated into the positive electrode layer and the negative electrode layer. In some cases, batteries were not manufactured.

  An object of one aspect of the present invention is to provide a method capable of manufacturing an all-solid battery in which the positive electrode layer and the negative electrode layer surely include a gel electrolyte, and to provide the all-solid battery.

  A method for manufacturing an all-solid-state battery according to one aspect of the present invention (hereinafter, also referred to as a “first method for manufacturing an all-solid-state battery”) includes gelling a first ionic liquid and the first ionic liquid. A first coating solution containing a first gelling agent, a first binder, and a positive electrode active material for the first main surface of a first current collector, and then applying the first ionic liquid to the first gel. Gelling with an agent and solidifying the first coating liquid with the first binder to form a first electrode having a positive electrode layer disposed on the first main surface of the first current collector. And a second coating liquid containing a second ionic liquid, a second gelling agent for gelling the second ionic liquid, a second binder and a negative electrode active material, on a second main surface of a second current collector. After the second ionic liquid is gelled with the second gelling agent, the second coating liquid is coated with the second ionic liquid. Forming a second electrode having a negative electrode layer disposed on the second main surface of the second current collector by solidifying the first electrode and the second electrode. Forming an electrode laminate by unidirectionally laminating the positive electrode layer of one electrode and the negative electrode layer of the second electrode so as to sandwich a separator containing a solid or gel electrolyte.

  In the first method for manufacturing an all-solid battery, a positive electrode layer is formed on a first main surface of a first current collector using a first coating solution, and a second current collector is formed using a second coating solution. A negative electrode layer is formed on the second main surface. The first coating liquid is a coating liquid for a positive electrode layer, and is a coating liquid in which a first gelling agent and a first binder are mixed with a first ionic liquid in addition to a positive electrode active material. The second coating liquid is a coating liquid for a negative electrode, and is a coating liquid in which a second gelling agent and a second binder are mixed with the second ionic liquid in addition to the negative electrode active material.

  Therefore, in addition to the positive electrode active material, the first ionic liquid and the first gelling agent are formed on the positive electrode layer formed by solidifying the first coating liquid applied on the first main surface by the action of the binder. Is also included. The first ionic liquid is gelled by the action of the gelling agent to become a gel electrolyte. Therefore, a positive electrode layer containing the gel electrolyte is obtained. Similarly, the negative electrode layer formed by the second coating liquid surely contains a gel electrolyte. An electrode laminate is formed by laminating the first electrode having the positive electrode layer and the second electrode having the negative electrode layer via a separator containing a gel electrolyte. Therefore, according to the method for manufacturing an all-solid-state battery, an all-solid-state battery in which the positive electrode layer and the negative electrode layer include the gel electrolyte without fail can be manufactured.

  The step of forming the first electrode includes the step of applying the first coating liquid on the first main surface of the first current collector, and the step of forming the first main surface of the first current collector. Coating the second coating liquid on the second main surface on the opposite side of the first current collector; and coating the first coating liquid on the first main surface of the first current collector in the first coating liquid. The first ionic liquid is gelled with the first gelling agent, and the first coating solution is solidified with the first binder, and the positive electrode layer is formed on the first main surface of the first current collector. Forming the second ionic liquid in the second coating liquid applied to the second main surface of the first current collector with the second gelling agent, Solidifying the second coating solution with the second binder to form the negative electrode layer on the second main surface of the first current collector. Forming process Applying the second coating liquid on the second main surface of the second current collector; and applying the second coating liquid on the first main surface of the second current collector opposite to the second main surface. Applying the first coating liquid, and applying the second ionic liquid in the second coating liquid applied to the second main surface of the second current collector to the second gel. Gelling with an agent and solidifying the second coating liquid with the second binder to form the negative electrode layer on the second main surface of the second current collector; The first ionic liquid in the first coating liquid applied to the first main surface of the current collector is gelled with the first gelling agent, and the first coating liquid is applied to the first coating liquid. Solidifying with a binder to form the positive electrode layer on the first main surface of the second current collector.

  The first electrode and the second electrode formed as described above are bipolar electrodes. Therefore, in the above method, an all solid state battery including a bipolar electrode can be manufactured.

  The first ionic liquid and the second ionic liquid may be the same ionic liquid.

  The first binder and the second binder are thermosetting resin binders, and the first coating liquid and the second coating liquid are heated by heating the first coating liquid and the second coating liquid. The working liquid may be solidified. When the first coating liquid and the second coating liquid are solidified by using the resin binder, the binder is not volatilized and no gas is generated. Therefore, for example, holes are not formed in the positive electrode layer and the negative electrode layer due to the gas.

  The first binder and the second binder may be the same binder.

  In a mode in which the first binder and the second binder are the same binder, the step of forming the electrode laminate includes one of the positive electrode layer of the first electrode and the negative electrode layer of the second electrode. Applying a third coating liquid containing a third ionic liquid, a third gelling agent for causing the third ionic liquid to gel, and the first binder to a base layer that is: The third coating liquid is sandwiched between the positive electrode layer or the negative electrode layer of the second electrode and a layer having a polarity opposite to that of the underlayer and the underlayer. Arranging one electrode and the second electrode, gelling the third ionic liquid with the third gelling agent, and forming the third coating liquid between the first electrode and the second electrode. The working liquid is solidified by the first binder, and the first electrode and the first electrode are solidified. A step of forming the separator between the electrodes, may have.

  In this case, the third coating liquid for forming the separator has the same binder as the binder used for forming the positive electrode layer and the negative electrode layer. Therefore, by forming the electrode laminate as described above, the positive electrode layer of the first electrode and the separator are joined, and the negative electrode layer of the second electrode and the separator are joined.

  The method may further include a step of forming a holding member for holding the first electrode and the second electrode on an outer peripheral surface of the electrode stack to obtain a power storage cell.

  The method may further include arranging a current collecting plate on the power storage cell so as to be adjacent to the power storage cell in the one direction and electrically connected to the power storage cell.

  A method for manufacturing an all-solid-state battery according to one aspect of the present invention (hereinafter, also referred to as a “second method for manufacturing an all-solid-state battery”) includes a current collector, a first main surface of the current collector, Forming a bipolar electrode having a positive electrode layer disposed on a second surface and a negative electrode layer disposed on a second main surface of the current collector opposite to the first main surface; and forming the plurality of bipolar electrodes on the current collector. Forming an electrode laminate by unidirectionally laminating electrodes via a separator containing a solid or gel electrolyte, wherein the step of forming the bipolar electrode comprises: A step of applying a first coating liquid containing an ionic liquid, a gelling agent for gelling the ionic liquid, a binder, and a positive electrode active material on the main surface; and the second main surface of the current collector On the above, the ionic liquid, the gelling agent, the binder and Applying a second coating solution containing a polar active material, and gelling the ionic liquid in the first coating solution applied to the first main surface with the gelling agent; Solidifying the first coating liquid to form the positive electrode layer on the first main surface; and applying the ionic liquid in the second coating liquid applied on the second main surface to the gel. Gelling with an agent and solidifying the second coating liquid to form the negative electrode layer on the second main surface.

  In the second method for manufacturing an all-solid-state battery, an all-solid-state battery including a bipolar electrode can be manufactured. Also in the above manufacturing method, the positive electrode layer is formed on the first main surface of the current collector using the first coating liquid, and the negative electrode layer is formed on the second main surface of the current collector using the second coating liquid. . The first coating liquid is a coating liquid for a positive electrode layer, and is a coating liquid in which a first gelling agent and a first binder are mixed with a first ionic liquid in addition to a positive electrode active material. The second coating liquid is a coating liquid for a negative electrode, and is a coating liquid in which a second gelling agent and a second binder are mixed with the second ionic liquid in addition to the negative electrode active material.

  Therefore, in addition to the positive electrode active material, the first ionic liquid and the first gelling agent are formed on the positive electrode layer formed by solidifying the first coating liquid applied on the first main surface by the action of the binder. Is also included. The first ionic liquid is gelled by the action of the gelling agent to become a gel electrolyte. Therefore, a positive electrode layer containing the gel electrolyte is obtained. Similarly, the negative electrode layer formed by the second coating liquid surely contains a gel electrolyte. An electrode laminate is formed by laminating the first electrode having the positive electrode layer and the second electrode having the negative electrode layer via a separator containing a gel electrolyte. Therefore, according to the method for manufacturing an all-solid battery, it is possible to manufacture an all-solid battery in which the positive electrode layer and the negative electrode layer each contain the gel electrolyte.

  An all-solid-state battery according to another aspect of the present invention is directed to a first solid-state battery in which a positive electrode layer including a gel electrolyte, a positive electrode active material, and a thermosetting resin binder is disposed on at least one main surface of the first current collector. An electrode, a second electrode in which a negative electrode layer including a gel electrolyte, a negative electrode active material, and the resin binder is disposed on at least one main surface of the second current collector; and the first electrode and the second electrode. And a separator including a solid or gel electrolyte and the binder, sandwiched between the positive electrode layer and the negative electrode layer. This all-solid-state battery can be suitably manufactured by, for example, the first method for manufacturing an all-solid-state battery.

  According to one aspect of the present invention, it is possible to provide a method capable of manufacturing an all-solid battery in which the positive electrode layer and the negative electrode layer definitely include the gel electrolyte, and the all-solid battery.

FIG. 1 is a schematic perspective view illustrating a power storage device according to one embodiment. FIG. 2A is a schematic perspective view of a power storage cell and a current collector in contact with the power storage cell, and FIG. 2B is a schematic side view of the power storage cell and a current collector in contact with the power storage cell. is there. FIG. 3 is a schematic sectional view of a power storage cell. FIG. 4 is a schematic sectional view taken along the line IV-IV in FIG. FIG. 5 is a schematic sectional view taken along line VV in FIG. FIG. 6A is a diagram illustrating a process of applying the first coating liquid to the current collector, and FIG. 6B is a diagram illustrating a process of forming the positive electrode layer. FIG. 7A is a diagram illustrating a process of applying the second coating liquid to the current collector, and FIG. 7B is a diagram illustrating a process of forming the negative electrode layer. FIG. 8A is a diagram illustrating a step of applying a third coating liquid to a base layer, and FIG. 8B is a view illustrating a step of arranging first and second electrodes and a step of forming a separator. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements will be denoted by the same reference symbols, without redundant description. The dimensional ratios in the drawings do not always match those described.

  The power storage device 1 illustrated in FIG. 1 is a power storage module used as a battery of various vehicles such as a forklift, a hybrid vehicle, and an electric vehicle. Power storage device 1 includes cell stack 2, connecting members 3 and 4 electrically connected to cell stack 2, a pair of restraining members 5 and 6 for restraining cell stack 2, cell stack 2 and restraining member 5, And a cover member 9 that covers a part of the cell stack 2. The insulating buffer member 7 is disposed between the cell stack 2 and the restraining member 6. Hereinafter, the direction in which the restraining members 5 and 6 restrain the cell stack 2 is referred to as a direction X (one direction) shown in FIG. 1, the direction intersecting or orthogonal to the direction X in the horizontal direction is referred to as a direction Y, and the directions X and A direction intersecting or orthogonal to Y is defined as a direction Z.

  The cell stack 2 has a plurality of power storage cells 11 arranged along the direction X. That is, the cell stack 2 is an aggregate of the plurality of power storage cells 11. The cell stack 2 includes, for example, 89 or more and 111 or less storage cells 11. In the present embodiment, the cell stack 2 includes 100 storage cells. Details of the configuration of the storage cell 11 will be described later. Although not shown in FIG. 1, the cell stack 2 also has a plurality of current collectors. The details of the current collector plate will also be described later.

  Connection member 3 is a conductive member (bus bar) that functions as a positive electrode of power storage device 1 and has a substantially flat shape. The connection member 3 is provided on one end side of the cell stack 2 in the direction Y. The connection member 3 is, for example, a metal plate or an alloy plate. The metal plate is, for example, a copper plate, an aluminum plate, a titanium plate, or a nickel plate. The alloy plate is, for example, a stainless steel plate (SUS301, SUS304, or the like) or an alloy plate of the above metal.

  The connecting member 3 extends along the direction X and overlaps the cell stack 2 and the insulating buffer member 7 in the direction Z, and protrudes along the direction X from one end of the main plate portion 3a on the restricting member 5 side. And a protruding plate portion 3b. The main plate portion 3a of the connection member 3 is electrically connected to each positive electrode terminal of the plurality of power storage cells 11 included in the cell stack 2. The protruding plate portion 3b of the connection member 3 is provided continuously to the main plate portion 3a. The end of the protruding plate portion 3b along the direction X is located outside the restraining member 5. The connecting member 3 is separated from the restraining members 5 and 6.

  The connection member 4 is a conductive member (bus bar) that functions as a negative electrode of the power storage device 1 and has a substantially flat shape. The connection member 4 is provided on the other end side of the cell stack 2 in the direction Y. The connection member 4 is, for example, a metal plate or an alloy plate, like the connection member 3. The connection member 4 may be the same metal plate or alloy plate as the connection member 3, or may be a different metal plate or alloy plate.

  The connecting member 4 extends in the direction X and protrudes in the direction X from one end of the main plate portion 4a on the restraining member 6 side, which overlaps the cell stack 2 and the insulating buffer member 8 in the direction Z. And a projecting plate portion 4b. The protruding plate portion 4b is provided on the opposite side of the connecting member 3 from the protruding plate portion 3b in the direction X. The main plate portion 4a of the connection member 4 is electrically connected to each negative electrode terminal of the plurality of power storage cells 11 included in the cell stack 2. The protruding plate portion 4b of the connection member 4 is provided continuously to the main plate portion 4a. The end of the protruding plate portion 4b along the direction X is located outside the restraining member 6. The connecting member 4 is separated from the restraining members 5 and 6 like the connecting member 3.

  Each of the restraining members 5 and 6 is a member that applies a restraining force (restraining load) to the cell stack 2 in the direction X, and is an end plate having a substantially L-shaped plate shape. The restraining member 5 is disposed on one end side of the cell stack 2 in the direction X, and extends along the direction X from a main portion 5a that applies a restraining load to the cell stack 2 and one end of the main portion 5a in the direction Z. And an extending portion 5b that extends. The extension 5b extends away from the cell stack 2. The restraining member 6 is disposed on the other end side of the cell stack 2 in the direction X, and extends along the direction X from one end of the main portion 6a that applies a restraining load to the cell stack 2 in one direction. And an extending portion 6b extending therefrom. The extension 6 b extends away from the cell stack 2, similarly to the extension 5 b of the restraining member 5.

  Each of the restraining members 5 and 6 is, for example, a plate made of metal or alloy. The restraining members 5 and 6 may be connected to each other via a connecting member using, for example, a fastening member (for example, a bolt and a nut). In this case, each of the restraining members 5 and 6 may be provided with a through hole or the like through which a connecting member such as a bolt extending in the direction X is inserted. Alternatively, each of the restraint members 5 and 6 may be fixed to a base or a case (not shown). In this case, each of the restraint members 5 and 6 may be provided with a through hole or the like through which a member for fixing them to the base or the like is inserted.

  Each of the insulating buffer members 7 and 8 is an insulating member for absorbing the expansion of the power storage cell 11, and has a substantially rectangular parallelepiped shape. The insulating buffer member 7 is disposed between the cell stack 2 and the restraining member 5 in the direction X. The insulating buffer member 8 is arranged between the cell stack 2 and the restraining member 6 in the direction X. The end faces of the insulating buffer members 7 and 8 facing the connection members 3 and 4 may be aligned with the end faces of the cell stack 2 facing the connection members 3 and 4. That is, the end faces may be flush with each other.

  Each of the insulating buffer members 7 and 8 includes, for example, polypropylene (PP), polyphenylene sulfide (PPS), and nylon 66 (PA66). At least one of the insulating buffer members 7, 8 may exhibit elasticity. The length (that is, thickness) of the insulating buffer members 7 and 8 along the direction X is, for example, 1 mm or more and 10 mm or less. In the present embodiment, the thickness of the insulating buffer members 7 and 8 is 5 mm.

  The cover member 9 is a member for regulating the movement of the power storage cell 11 in the direction Z, and has a substantially inverted U-shaped plate shape. The cover member 9 is provided between the connection members 3 and 4 in the direction Y, and is separated from the connection members 3 and 4. The cover member 9 includes a cover portion 9a extending in the direction X, a first mounting portion 9b extending in one direction from the one end of the cover portion 9a in the direction X, and a cover portion 9a in the direction X. And a second mounting portion 9c extending along the direction Z from the end.

  The first mounting portion 9b is fixed to the restraining member 5 via a fastening member E or the like. The second mounting portion 9c is fixed to the restraining member 6 via a fastening member or the like, like the first mounting portion 9b. For this reason, in this embodiment, the cover member 9 functions as a connecting member for connecting the restraining members 5 and 6. The cover member 9 is, for example, a metal plate or an alloy plate.

  Next, the details of the power storage cell 11 and the current collector included in the cell stack 2 will be described with reference to FIGS. First, the configuration of the storage cell 11 will be described in detail.

  As shown in FIGS. 2A and 2B, the storage cell 11 is a unit cell having a substantially rectangular parallelepiped shape. In the power storage cell 11, the side along the direction X is the shortest, and the side along the direction Y is the longest. The storage cell 11 is an all-solid-state battery. The storage cell 11 is a secondary battery such as a lithium ion secondary battery. In the present embodiment, the power storage cell 11 is a bipolar type lithium ion secondary battery.

  The storage cell 11 is sandwiched between the positive electrode current collector 12 and the negative electrode current collector 13 in the direction X, and is electrically connected to the connection member 3 via the positive electrode current collector 12 and the negative electrode current collector The connection member 13 is electrically connected to the connection member 4.

  The storage cell 11 includes an electrode stack 14 having a pair of main surfaces 14 a and 14 b intersecting in the direction X and an outer peripheral surface 14 c connecting the main surfaces 14 a and 14 b, and a holding member provided at least on the outer peripheral surface 14 c of the electrode stack 14. A member 15.

  As shown in FIG. 3, the electrode laminate 14 has a plurality of bipolar electrodes 16 (a plurality of electrodes) and a plurality of separators (separators including a solid or gel electrolyte layer) 17. The plurality of bipolar electrodes 16 and the plurality of separators 17 are alternately arranged along the direction X.

  Each of the plurality of bipolar electrodes 16 includes a current collector (a first current collector and a second current collector) 21, a positive electrode layer 22, and a negative electrode layer 23. The current collector 21 has a pair of main surfaces 21a and 21b crossing in the direction X. The positive electrode layer 22 is provided on the main surface (first main surface) 21 a of the current collector 21, and the negative electrode layer 23 is provided on the main surface (second main surface) 21 b of the current collector 21. For this reason, the current collector 21 is sandwiched between the positive electrode layer 22 and the negative electrode layer 23 along the direction X.

  The current collector 21 is a sheet-like conductive member, and has a substantially rectangular shape. The current collector 21 is, for example, a metal foil or an alloy foil. The metal foil is, for example, a copper foil, an aluminum foil, a titanium foil, or a nickel foil. When the current collector 21 is a metal foil, the metal foil may be an aluminum foil from the viewpoint of securing mechanical strength. The alloy foil is, for example, a stainless steel foil (SUS301, SUS304, or the like) or an alloy foil of the above metal. When the current collector 21 is an alloy foil, or when the current collector 21 is a metal foil other than the aluminum foil, the surface of the current collector 21 may be coated with aluminum. The thickness of the current collector 21 is, for example, 5 μm or more and 20 μm or less. In the present embodiment, the thickness of the current collector 21 is 10 μm.

  The positive electrode layer 22 is a layered member including at least a positive electrode active material, a gel electrolyte, and a binder, and has a substantially rectangular shape. The negative electrode layer 23 is a layered member containing at least a negative electrode active material, a gel electrolyte, and a binder, and has a substantially rectangular shape. The materials of the positive electrode layer 22 and the negative electrode layer 23 will be described later.

  As shown in FIG. 3, the separator 17 is a layered member that separates the adjacent bipolar electrodes 16, and has a substantially rectangular shape. The separator 17 includes a gel electrolyte and a binder contained in the positive electrode layer 22 and the negative electrode layer 23. The thickness of the separator 17 is, for example, 1 μm or more and 10 μm or less. In the present embodiment, the thickness of the separator 17 is 5 μm.

  Current collectors 21 are provided at both ends of the electrode stack 14 in the direction X. The negative electrode layer is not disposed on the main surface 21b of the current collector 21 disposed at one end (the right side of the paper surface in FIG. 3) of the electrode stack 14 in the direction X. Therefore, the current collector 21 corresponds to the positive electrode terminal of the electrode stack 14, and the main surface 21 b corresponds to the main surface 14 a of the electrode stack 14. The negative electrode layer is not arranged on the main surface 21a of the current collector 21 arranged at the other end of the electrode stack 14 in the direction X (on the left side in FIG. 3). Therefore, the current collector 21 corresponds to the negative electrode terminal of the electrode stack 14, and the main surface 21 a corresponds to the main surface 14 b of the electrode stack 14.

  The holding member 15 is a member that holds the plurality of bipolar electrodes 16, the plurality of separators 17, the positive electrode terminal, and the negative electrode terminal included in the electrode stack 14, and has insulating properties. In the present embodiment, the holding member 15 prevents the short-circuit between the bipolar electrodes 16 in the electrode stack 14 and the sealing member having a substantially rectangular frame shape so as to seal the outer peripheral surface 14 c of the electrode stack 14. Can also function as a short-circuit prevention member.

  The holding member 15 has an inner peripheral surface 15a in contact with the outer peripheral surface 14c of the electrode stack 14, an outer peripheral surface 15b located on the opposite side of the inner peripheral surface 15a, and a side surface 15c intersecting in the direction X. The side surface 15c is provided substantially parallel to the main surfaces 14a and 14b of the electrode stack 14. In the present embodiment, the side surface 15c located at one end in the direction X (right side of the paper surface in FIG. 3) is flush with the main surface 14a, and the side surface located at the other end in the direction X (right side of the paper surface in FIG. 3). 15c is flush with the main surface 14b.

  The holding member 15 includes, for example, a resin member having heat resistance. The resin member exhibiting heat resistance is, for example, polyimide, PP, PPS, PA66, or the like. The thickness of the holding member 15 is, for example, 1 mm or more and 10 mm or less. In this case, it is possible to prevent damage to the holding member 15 due to heat or the like and reduce the weight of the power storage cell 11. The thickness of the holding member 15 corresponds to the distance between the inner peripheral surface 15a and the outer peripheral surface 15b along the direction Y or the direction Z. In the present embodiment, the thickness of the holding member 15 is 5 mm.

  Next, returning to FIGS. 2A and 2B, the configuration of the positive electrode current collector 12 and the negative electrode current collector 13 will be described.

  The positive electrode current collector 12 is a conductive member that comes into contact with the electrode stack 14 and has a plate shape. The positive electrode current collector plate 12 is adjacent to the power storage cell 11 along the direction X. The positive electrode current collector plate 12 includes a main body 121 that contacts the current collector 21 functioning as a positive electrode terminal, and a protrusion 123 that protrudes from a part of the edge 122 of the main body 121 along the direction Z. The main body 121 is a portion that overlaps the bipolar electrode 16 and the separator 17 in the direction X, and has a substantially rectangular shape. In the present embodiment, when the positive electrode current collector plate 12 is sandwiched between the two power storage cells 11 along the direction X, one surface of the main body 121 contacts one power storage cell 11 and the other surface of the main body 121 is It contacts the other storage cell 11. At this time, the positive electrode current collector plate 12 is in contact with the positive electrode terminal of each power storage cell 11 and is not in contact with the current collector 21 functioning as a negative electrode terminal.

  The protruding portion 123 of the positive electrode current collector plate 12 that is in contact with the power storage cell 11 is bent such that its tip is separated from the electrode stack 14 of the power storage cell 11. Therefore, the protruding portion 123 has a base end portion 123a, a front end portion 123b extending along the direction X so as to be separated from the electrode stack 14, and a bent portion 123c. The tip 123b does not overlap with the electrode laminate 14 in the direction Z, nor does it contact the outer peripheral surface 15b of the holding member 15 in the power storage cell 11.

  The negative electrode current collector 13 is a conductive member that comes into contact with the electrode laminate 14 and has a plate shape. The negative electrode current collector 13 is adjacent to the power storage cell 11 along the direction X in the same manner as the positive electrode current collector 12. The negative electrode current collector 13 has a main body 131 that contacts the current collector 21 functioning as a negative electrode terminal, and a protrusion 133 that protrudes from a part of the edge 132 of the main body 131 along the direction Z. The main body 131 is a portion overlapping the bipolar electrode 16 and the separator 17 in the direction X, and has a substantially rectangular shape. In the present embodiment, when the negative electrode current collector plate 13 is sandwiched between the two power storage cells 11 along the direction X, one surface of the main body 131 contacts one power storage cell 11 and the other surface of the main body 131 is It contacts the other storage cell 11. At this time, the negative electrode current collector plate 13 is in contact with the negative electrode terminal of each power storage cell 11 and is not in contact with the positive electrode terminal. The bent portion 123c is bent so as to be substantially perpendicular to the direction Y.

  As described above, in the present embodiment, the positive electrode current collector plate 12 comes into contact with the positive electrode terminal of each power storage cell 11. For this reason, in the present embodiment, the plurality of power storage cells 11 in the cell stack 2 are connected in parallel via the positive current collector 12 and the negative current collector 13.

  The protruding portion 133 of the negative electrode current collector plate 13 is also bent so that its tip is separated from the electrode stack 14 in the power storage cell 11. Therefore, the protruding portion 133 has a base end portion 133a, a front end portion 133b extending along the direction X so as to be separated from the electrode stack 14, and a bent portion 133c. The tip portion 133b does not overlap with the electrode stack 14 in the direction Z, and does not contact the outer peripheral surface 15b of the holding member 15 in the power storage cell 11.

  As shown in FIG. 4, in the cell stack 2, a plurality of power storage cells 11 and a plurality of current collectors are alternately arranged along the direction X. More specifically, the cell stack 2 is configured by a group in which the power storage cell 11, the positive electrode current collector 12, the power storage cell 11, and the negative electrode current collector 13 are sequentially arranged in the direction X. ing. To each of the storage cells 11 and each of the current collectors, a restraining force along the direction X is applied by the restraining member 5 via the insulating buffer member 7.

  The positive current collector plate 12 shown in FIG. 4 that is in contact with the outermost power storage cell 11 in the direction X is disposed between the power storage cell 11 and the insulating buffer member 7. The main body 121 of the electric plate 12 is in contact with the main surface 7 a of the insulating buffer member 7. Hereinafter, the outermost positive electrode current collector 12 shown in FIG. 4 in the direction X is referred to as an outermost positive electrode current collector 12A. The insulating cushioning member 7 has a main surface 7a crossing the direction X and contacting the main body 121, and an outer peripheral surface 7b extending along the direction X from an edge of the main surface 7a.

  The protrusion 123 of each positive electrode current collector 12 except for the outermost positive electrode current collector 12A extends along the side surface 15c and the outer peripheral surface 15b of the holding member 15. The protruding portion 123 of the outermost positive electrode current collector plate 12A extends along the main surface 7a and the outer peripheral surface 7b of the insulating buffer member 7.

  The base end 123 a of the protrusion 123 does not overlap with the electrode stack 14 in the direction X, and is provided along the side surface 15 c of the holding member 15. In the present embodiment, the whole of the base end portion 123a is in close contact with the side surface 15c of the corresponding holding member 15. In addition, the entire base end portion 123a of the outermost positive electrode current collector plate 12A is in close contact with the main surface 7a of the insulating buffer member 7.

  The tip 123b of the protruding portion 123 of the positive electrode current collector 12 except for the outermost positive electrode current collector 12A overlaps the electrode laminate 14 and the connection member 3 in the direction Z, and extends along the outer peripheral surface 15b of the holding member 15. Extending. In the present embodiment, the entire distal end portion 123b is in close contact with both the outer peripheral surface 15b of the holding member 15 and the connection member 3. The welding portion W1 is formed on a region where the tip portion 123b, the corresponding holding member 15 and the connection member 3 overlap in the direction Z, and the holding member 15 and the tip portion 123b are in contact with each other. Provided. The welded portion W1 is a portion that joins the positive electrode current collector plate 12 and the connection member 3, and is provided at a position where the distal end portion 123b and the connection member 3 are in contact. The welding portion W1 is formed by, for example, laser welding or the like. When the welded portion W1 is formed, the holding member 15 also functions as a pedestal in a welding process.

  The tip 123b of the protruding portion 123 in the outermost positive electrode current collector plate 12A extends along the direction X so as to be away from the power storage cell 11. For this reason, the tip portion 123b overlaps with the insulating buffer member 7 in the direction Z, and extends along the outer peripheral surface 7b of the insulating buffer member 7. In the present embodiment, the entire distal end portion 123b is in close contact with both the outer peripheral surface 7b of the insulating buffer member 7 and the connection member 3. A welding portion W2 is provided on a region where the distal end portion 123b, the insulating buffer member 7, and the connecting member 3 overlap in the direction Z, and the insulating buffer member 7 and the distal end portion 123b are in contact with each other. Can be The welded portion W2 is a portion that joins the outermost positive electrode current collector plate 12A and the connection member 3. The welded portion W2 is formed by, for example, laser welding or the like, like the welded portion W1. When the welded portion W2 is formed, the insulating buffer member 7 also functions as a pedestal in the welding process.

  Except for the outermost positive electrode current collector 12A, the tip 123b of the positive electrode current collector 12 and the tip 123b of the outermost positive electrode current collector 12A extend in the same direction. Specifically, the tip portion 123b extends toward one side in the direction X.

  The negative electrode current collector 13 that is in contact with the outermost power storage cell 11 in the direction X shown in FIG. 5 is disposed between the power storage cell 11 and the insulating buffer member 8, and The main body 131 of the plate 13 is in contact with the main surface 8 a of the insulating buffer member 8. Hereinafter, the negative electrode current collector 13 located at the outermost side in the direction X shown in FIG. 5 is also referred to as an outermost negative electrode current collector 13A.

  The protrusion 133 of each negative electrode current collector 13 except for the outermost negative electrode current collector 13 </ b> A is arranged along the side surface 15 c and the outer peripheral surface 15 b of the holding member 15. The protruding portion 133 of the outermost negative electrode current collector plate 13A is arranged along the main surface 8a and the outer peripheral surface 8b of the insulating buffer member 8.

  The protrusion 133 of the negative electrode current collector 13 except for the outermost negative electrode current collector 13A overlaps the electrode laminate 14 and the connection member 4 in the direction Z, and extends along the outer peripheral surface 15b of the holding member 15. I have. In the present embodiment, the protrusion 133 is in close contact with both the outer peripheral surface 15 b of the holding member 15 and the connection member 4. The welding portion W3 is formed on a region where the tip 133b, the corresponding holding member 15 and the connecting member 4 overlap in the direction Z, and the holding member 15 and the tip 133b are in contact with each other. Provided. The welded portion W3 is a portion that joins the negative electrode current collector plate 13 and the connection member 4, and is provided at a position where the tip portion 133b and the connection member 4 are in contact. The welding portion W3 is formed by, for example, laser welding or the like. When the welded portion W3 is formed, the holding member 15 also functions as a pedestal in the welding process.

  The distal end portion 133b of the protruding portion 133 in the outermost negative electrode current collector plate 13A extends along the direction X so as to be away from the power storage cell 11. For this reason, the tip portion 133b overlaps with the insulating cushioning member 8 in the direction Z, and extends along the outer peripheral surface 8b of the insulating cushioning member 8. In the present embodiment, the entire distal end portion 133b is in close contact with both the outer peripheral surface 8b of the insulating buffer member 8 and the connection member 4. A welding portion W4 is provided on a region where the distal end portion 133b, the insulating buffer member 8, and the connecting member 4 overlap in the direction Z, and the insulating buffer member 8 and the distal end portion 133b are in contact with each other. Can be The welded portion W4 is a portion that joins the outermost negative electrode current collector plate 13A and the connection member 4. The welded portion W4 is formed by, for example, laser welding or the like, similarly to the welded portion W3. When the welding portion W4 is formed, the insulating buffer member 8 also functions as a pedestal in the welding process.

  The tip 133b of the negative electrode current collector 13 excluding the outermost negative electrode current collector 13A and the tip 133b of the outermost negative electrode current collector 13A extend along the same direction. Specifically, the tip portion 133b extends toward the other side in the direction X. For this reason, the extending direction of the distal end portion 123b of each positive electrode current collector plate 12 and the extending direction of the distal end portion 133b of each negative electrode current collector plate 13 are opposite to each other.

  Next, a method for manufacturing power storage device 1 will be described. When the power storage device 1 is manufactured, the power storage cell 11 is manufactured (a power storage cell manufacturing process). Since the storage cell 11 is an all-solid-state battery, the storage cell 11 is manufactured by the method for manufacturing an all-solid-state battery according to the present embodiment.

  The method for manufacturing the storage cell 11 (the all-solid-state battery according to the present embodiment) includes a step of forming the bipolar electrode 16 (a step of forming the first electrode and a step of forming the second electrode) and the step of forming the electrode stack 14. And

[Step of forming bipolar electrode]
In the step of forming the bipolar electrode, first, as shown in FIG. 6A, the first coating liquid is applied on the main surface 21a of the current collector 21 to form the first coating film F1. (Step of applying the first coating liquid). The first coating liquid includes an ionic liquid (first ionic liquid), a gelling agent for gelling the ionic liquid (first gelling agent), a binder (first binder), and a positive electrode active material.

  The ionic liquid is a non-volatile liquid, for example, a liquid obtained by melting an imide salt such as LiFSA in a solvent such as tetraglyme (G4). The ionic liquid is gelled by the gelling agent to become a gelled ionic liquid. In this specification, the gelled ionic liquid is also called a gel electrolyte.

  The gelling agent is mixed with the ionic liquid to gel the ionic liquid. Examples of gelling agents include silica particles. The gelling agent of the present embodiment is silica particles. The ionic liquid (gel-like electrolyte) to which the gelling agent is added and gelled by the gelling agent is gelled by applying a gelation release condition (for example, by applying a stress such as a shear force). It is released and has a certain liquidity. In other words, the ionic liquid is gelled by the gelling agent in a state in which the gelling release condition is not applied (for example, in a state of standing). Hereinafter, a condition for realizing a state in which the gelling release condition is not applied may be referred to as a gelling condition. The gelling agent is an ionic liquid such that the gelled electrolyte, which is a gelled ionic liquid, does not show fluidity completely or almost completely (for example, the viscosity at 20 ° C. is 0.1 Pa · S or more). It only has to be mixed. For example, the mixing amount of the gelling agent is 10 wt% to 20 wt%.

  The positive electrode active material is, for example, a composite oxide, metallic lithium, sulfur, or the like. The composition of the composite oxide includes, for example, at least one of manganese, titanium, nickel, cobalt, and aluminum, and lithium. The mixing amount of the positive electrode active material in the ionic liquid is set based on the electric conductivity of the positive electrode layer 22 and the like.

  The binder is a binder for binding the positive electrode active material and the binder or the binders. In the present embodiment, the binder is a thermosetting resin binder. Examples of the thermosetting resin binder include a polyimide resin (for example, polyimide) and a polyamideimide resin. The resin binder of the present embodiment is polyimide. The amount of the binder mixed with the ionic liquid is set according to the weight of the ionic liquid, and is, for example, 2 wt% to 10 wt%.

  The first coating liquid may include a conductive additive for increasing the electron conductivity of the positive electrode layer 22. The conductive assistant is, for example, acetylene black, carbon black, graphite, or the like.

  As described above, the ionic liquid mixed with the gelling agent gels. Therefore, when the ionic liquid is gelled in the preparation stage of the first coating liquid, the step of applying the first coating liquid causes the ionic liquid to gel into the gelled ionic liquid in which the positive electrode active material and the binder are mixed. The release condition is once applied (for example, a shearing force is applied) to make the gel-like ionic liquid into a slurry-like first coating liquid. After that, the first coating liquid is applied to the main surface 21a.

  After forming the first coating film F1, the first coating film F1 (first coating liquid applied to the main surface 21a) is solidified using a binder to form the positive electrode layer 22 on the main surface 21a. (Step of forming positive electrode layer).

  The first coating film F1 contains a gelling agent, and the gelling release condition is not applied in the step of forming the positive electrode layer. In other words, the step of forming the positive electrode layer under gelling conditions (for example, in a state of standing) is performed. Therefore, in the step of forming the positive electrode layer, the ionic liquid is gelled by the gelling agent to form a gel electrolyte.

  Since the binder is a thermosetting resin binder, in the step of forming the positive electrode layer, the positive electrode layer 22 is obtained by heating the first coating film F1. The heating temperature only needs to be a temperature at which the ionic liquid (or gelling electrolyte) and the positive electrode active material are not deteriorated among the temperatures according to the characteristics (for example, the curing temperature) of the binder. An example of the heating temperature is 100C to 200C. Heating can be performed, for example, by baking in a chamber.

  The first coating film F1 includes a gelling agent, a positive electrode active material, an ionic liquid, and a binder. Therefore, the positive electrode layer 22 formed as described above includes a gel electrolyte (an ionic liquid gelled with a gelling agent), a positive electrode active material, and a binder. In the case where the first coating film F1 contains a conductive aid or the like, the positive electrode layer 22 also contains a conductive aid or the like.

  Next, as shown in FIG. 7A, an ionic liquid (second ionic liquid), a gelling agent (second gelling agent), and a binder (second binder) are formed on the main surface 21b of the current collector 21. ) And a second coating liquid containing the negative electrode active material to form a second coating film (a step of applying the second coating liquid).

  The example of the ionic liquid may be the same as the example of the ionic liquid of the first coating liquid. In the present embodiment, the ionic liquid of the second coating liquid is the same as the ionic liquid of the first coating liquid. Examples of the gelling agent and the amount of the gelling agent mixed with the ionic liquid may be the same as those of the ionizing gelling agent of the first coating liquid. In the present embodiment, the gelling agent of the second coating liquid and the amount of the gelling agent mixed with the ionic liquid are the same as those of the gelling agent of the first coating liquid.

  The negative electrode active material is, for example, graphite, highly oriented graphite, mesocarbon microbeads, carbon such as hard carbon and soft carbon, an alkali metal such as lithium and sodium, a metal compound, an element or a compound thereof which can be alloyed with lithium, and boron. Such as added carbon. Examples of elements that can be alloyed with lithium include silicon (silicon) and tin.

  The binder is a binder for binding the negative electrode active material to the binder or the binders. In the present embodiment, the binder is a thermosetting resin binder. The example of the thermosetting resin binder is the same as the example of the binder contained in the first coating liquid. An example of the amount of the binder mixed with the ionic liquid is the same as in the case of the first coating liquid. In the present embodiment, the mixing amount in the binder and the ionic liquid is the same as in the case of the first coating liquid.

  The second coating liquid may contain a conductive additive, as in the case of the first coating liquid. Examples of the conductive assistant are the same as those in the case of the first coating liquid.

  After forming the second coating film F2, the second coating film (the second coating liquid applied to the main surface 21b) is solidified, and the gelling conditions are applied to the second coating film F2. Thereby, as shown in FIG. 7B, the negative electrode layer 23 is formed on the main surface 21b (step of forming the negative electrode layer).

  The second coating film F2 contains a gelling agent, and the gelling release condition is not applied in the step of forming the negative electrode layer. In other words, the step of forming the negative electrode layer under the gelling condition (for example, in a state of standing) is performed. Therefore, in the step of forming the negative electrode layer, the ionic liquid is gelled by the gelling agent to form a gel electrolyte.

  Since the binder is a thermosetting resin binder, in the step of forming the negative electrode layer, the negative electrode layer 23 is obtained by heating the second coating film F2. The heating temperature only needs to be a temperature at which the ionic liquid (or gelling electrolyte) and the negative electrode active material are not deteriorated among the temperatures according to the characteristics (for example, the curing temperature) of the binder. As described here, when forming the negative electrode layer 23 after forming the positive electrode layer 22, the heating temperature needs to be a temperature at which the positive electrode layer 22 does not deteriorate. An example of the heating temperature is 100C to 200C. Examples of the heating method are the same as those in the step of forming the positive electrode layer. In the present embodiment, the heating method is the same as the case of the step of forming the positive electrode layer.

  The second coating film F2 includes a gelling agent, a negative electrode active material, an ionic liquid, and a binder. Therefore, the negative electrode layer 23 formed as described above includes a gel electrolyte (an ionic liquid gelled with a gelling agent), a negative electrode active material, and a binder. When the second coating film F2 contains a conductive additive and the like, the negative electrode layer 23 also contains a conductive additive and the like.

  Since the binder contained in the first coating liquid and the second coating liquid is a thermosetting resin binder, the first coating film F1 and the second coating film F2 are formed in the step of forming the positive electrode layer and the step of forming the negative electrode layer. By heating the coating film F2, the positive electrode layer 22 and the negative electrode layer 23 are obtained. The heating temperature is a temperature at which the ionic liquid (or gel electrolyte) and the active material (including the positive electrode active material and the negative electrode active material) do not change, as described above, of the temperature according to the characteristics of the binder (for example, the curing temperature). I just need. In other words, when a thermosetting resin binder is used as the binder as in the present embodiment, the resin binder is a resin binder curable at a temperature at which the ionic liquid (or gel electrolyte) and the active material do not deteriorate. Is selected.

  After forming the plurality of bipolar electrodes 16 in the bipolar electrode forming step, the electrode stack 14 is formed by laminating the formed bipolar electrodes 16 in one direction via a separator 17 containing a gel electrolyte. (Step of forming an electrode laminate). An example of a process for forming an electrode laminate will be described. For convenience of explanation, one of the two bipolar electrodes 16 sandwiching the separator 17 is referred to as a first bipolar electrode (first electrode) 16A, and the other is referred to as a second bipolar electrode (second electrode) 16B.

  First, as shown in FIG. 8A, an ionic liquid (third ionic liquid), a gelling agent (third gelling agent), and a binder are provided on the positive electrode layer (base layer) 22 of the first bipolar electrode 16A. A third coating liquid for a separator containing the (first binder) is applied to form a third coating film F3 (a step of applying the third coating liquid). Thereafter, as shown in FIG. 8B, the third coating film F3 (the applied third coating solution) is applied to the negative electrode layer 23 of the second bipolar electrode 16B (a layer having a polarity opposite to that of the underlying layer). ) And the positive electrode layer 22 of the first bipolar electrode 16A, the second bipolar electrode 16B is arranged on the third coating film F3 (the step of arranging the first electrode and the second electrode). Subsequently, the third coating film F3 disposed between the first bipolar electrode 16A and the second bipolar electrode 16B is solidified to form the separator 17 between the first bipolar electrode 16A and the second bipolar electrode 16B. (Step of forming a separator).

  The third coating film F3 contains a gelling agent, and the gelling release condition is not applied in the step of forming the separator. In other words, the step of forming the separator under gelling conditions (for example, in a state of standing) is performed. Therefore, in the step of forming the separator, the ionic liquid is gelled by the gelling agent to form a gel electrolyte.

  Since the binder of the third coating liquid is the same as the binder of the first coating liquid and the second coating liquid, in the step of forming the separator, the third coating film F3 is heated by heating the third coating film F3. The three-coated film F3 is heated. The heating conditions and the heating method are the same as those for the first coating film F1 and the second coating film F2.

  The third coating film F3 includes a gelling agent, an ionic liquid, and a binder, but does not include an active material. Therefore, the separator 17 formed as described above does not contain an active material, but contains a gel electrolyte (an ionic liquid gelled with a gelling agent) and a binder.

  When three or more bipolar electrodes 16 are stacked, the second bipolar electrode 16B is regarded as a new first bipolar electrode 16A, and a step of applying a third coating liquid and a step of arranging the first electrode and the second electrode By repeating the process of forming the separator, the electrode laminate 14 having three or more bipolar electrodes 16 is obtained.

  Alternatively, after performing the step of applying the third coating liquid and the step of arranging the first and second electrodes, the second bipolar electrode 16B is regarded as a new first bipolar electrode 16A, and the third coating is performed. The step of applying the working liquid and the step of arranging the first electrode and the second electrode are repeated to form a stacked body in which the plurality of bipolar electrodes 16 are stacked via the third coating liquid, and then the stack is formed. The electrode laminate 14 may be formed by heating the body to solidify the third coating liquid and applying gelling conditions.

  In the description of the step of forming the electrode laminate, the positive electrode layer 22 of the first bipolar electrode 16A has been described as the underlying layer. However, the negative electrode layer 23 of the first bipolar electrode 16A may be a base layer. In this case, the positive electrode layer 22 of the second bipolar electrode 16B is a layer whose polarity is opposite to that of the underlayer.

  After the electrode stack 14 is formed as described above, the holding member 15 holding the plurality of bipolar electrodes 16 is formed on the outer peripheral surface 14c of the electrode stack 14 to obtain the electricity storage cell 11 (forming the holding member). Process). When the material of the holding member 15 is a resin, the holding member 15 is formed, for example, by applying a resin to the outer peripheral surface 14c and then curing the resin.

  In the example of the method for manufacturing a power storage cell, the embodiment in which the positive electrode layer 22 is formed before the negative electrode layer 23 is formed has been described. However, the negative electrode layer 23 may be formed before the positive electrode layer 22. Alternatively, after the first coating liquid and the second coating liquid are coated on the main surface 21a and the main surface 21b, the gelation of the ionic liquid is advanced and the fluidity is reduced. After forming the F1 and the second coating film F2 (that is, after performing the steps of applying the first coating liquid and the second coating liquid), a step of forming a positive electrode layer and a step of forming a negative electrode layer May be implemented together.

  When manufacturing the power storage device 1, a plurality of power storage cells 11 are manufactured by the above-described method for manufacturing a power storage cell. Thereafter, a plurality of power storage plates including a plurality of power storage cells 11, a positive electrode current collector 12 and a negative electrode current collector 13, connecting members 3, 4, a pair of restraining members 5, 6, insulating cushioning members 7, 8, and a cover member The power storage device 1 is obtained by assembling the power storage device 1 with the use of the power storage device 9. An example of a method of assembling the power storage device 1 will be described.

  The plurality of manufactured power storage cells 11 and the plurality of current collectors (including the positive current collector 12 and the negative current collector 13) are alternately arranged along the direction X to obtain the cell stack 2 (the cell stack 2). Manufacturing process). In the manufacturing process of the cell stack, the positive electrode current collector 12 and the negative electrode current collector 13 are moved with respect to the power storage cell 11 so that the power storage cell 11 is sandwiched between the positive electrode current collector 12 and the negative electrode current collector 13 along the direction X. (The process of arranging the current collector plate).

  Thereafter, the cell stack 2 is restrained by the pair of restraining members 5 and 6 via the insulating buffer members 7 and 8 (a process of restraining by the restraining members). The arrangement relationship between the cell stack 2, the insulating buffer members 7, 8 and the pair of restraining members 5, 6 and the example of the restraining method using the restraining members 5, 6 are as described above.

  Further, the power storage device 1 is obtained by attaching the connection members 3 and 4 and the cover member 9 to the cell stack 2 (a process of attaching the connection member and the cover member). The attaching step of the connecting member and the cover member may be before or after the step of restraining by the restraining members 5 and 6, or may be included in the step of restraining by the restraining members 5 and 6. The step of arranging the current collecting plate may be included in the step of restraining by the restraining member.

  In the method of manufacturing the power storage cell 11 (the method of manufacturing the all-solid-state battery of the present embodiment), the positive electrode layer 22 and the negative electrode layer 23 are formed on the current collector 21 using the first coating liquid and the second coating liquid. . The first coating liquid is a coating liquid for a positive electrode layer, and is a coating liquid in which an ionic liquid is mixed with a gelling agent and a binder in addition to a positive electrode active material. The second coating liquid is a coating liquid for a negative electrode, and is a coating liquid in which an ionic liquid is mixed with a gelling agent and a binder in addition to a negative electrode active material.

  Therefore, the positive electrode layer 22 formed by solidifying (for example, hardening) the first coating film F1 obtained by applying the first coating liquid to the main surface 21a by the binding force of the binder has a positive electrode active layer. Besides substances, ionic liquids and gelling agents are also included. The ionic liquid is gelled by the action of the gelling agent to form a gel electrolyte. As described above, since the positive electrode layer 22 is formed by using the first coating liquid containing the positive electrode active material and the ionic liquid in advance, the positive electrode layer 22 containing the gel electrolyte is reliably obtained. Similarly, the negative electrode layer 23 formed by the second coating liquid contains a gel electrolyte. In the positive electrode layer 22 and the negative electrode layer 23 formed as described above, it is considered that the gel electrolyte is confined in a small region separated by the action of the binder in the positive electrode layer 22 and the negative electrode layer 23. The electrode laminate 14 is formed by laminating the bipolar electrode 16 having the positive electrode layer 22 and the negative electrode layer 23 with the separator 17 interposed therebetween. Therefore, according to the method for manufacturing an all-solid-state battery of the present embodiment, it is possible to manufacture the storage cell 11 as an all-solid-state battery in which the electrode layer surely contains the gel electrolyte. Further, by manufacturing the power storage device 1 using the power storage cells 11, the power storage device 1 also functions as an all-solid-state battery.

  In the method illustrated in FIGS. 6A to 8B, when the electrode laminate 14 is formed, the binder included in the third coating liquid for the separator includes the first coating liquid and the second coating liquid. The same embodiment as the binder contained in the coating liquid has been described. In this embodiment, when the third coating liquid is solidified, the separator 17 and the positive electrode layer 22 and the negative electrode layer 23 that are in contact with the separator 17 are easily bonded by the action of the binder. As a result, the fixing (restriction) of the plurality of bipolar electrodes 16 included in the electrode stack 14 can be simplified, and the plurality of bipolar electrodes 16 are not easily separated.

  In a mode in which a thermosetting resin binder is used as the binder as exemplified in the present embodiment, no gas is generated due to the volatilization of the binder when the coating liquid is solidified. Therefore, even if the positive electrode layer 22 and the negative electrode layer 23 are formed, holes and the like due to the release of the gas do not occur. Therefore, good positive electrode layers 22 and negative electrode layers 23 can be obtained while containing the gel electrolyte. The binder is not limited to a thermosetting binder, but is preferably a binder that volatilizes and does not generate gas when the coating liquid containing the binder is solidified.

  The embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the invention.

  For example, the method for manufacturing an all-solid-state battery according to the present invention includes a first electrode in which a positive electrode layer is formed on both the first main surface and the second main surface of the current collector; The second electrode in which the negative electrode layer is formed on both of the second main surfaces and the second electrode may be applied to an all-solid-state battery including an electrode stack laminated via a separator containing a gel electrolyte.

  In this case, the positive electrode layer and the negative electrode layer may be formed in the same manner as when forming the positive electrode layer and the negative electrode layer of the bipolar electrode. Further, when the first electrode and the second electrode are laminated via the separator, the method of laminating the separator is such that the first electrode is formed by the first bipolar electrode 16A shown in FIGS. 8A and 8B. The electrode stack described with reference to FIGS. 6A to 8B is formed by making the second electrode correspond to the second bipolar electrode 16B shown in FIG. 8B. The same method as that of the step of applying can be applied.

  The first electrode may have a configuration in which a positive electrode layer is formed only on the first main surface, and the second electrode may have a configuration in which a positive electrode layer is formed only on the second main surface.

  The current collectors of the plurality of electrodes included in the electrode stack may be different (for example, different materials and the like). Similarly, the ionic liquid of the first coating liquid, the second ionic liquid of the second coating liquid, and the third ionic liquid of the third coating liquid may be different from each other in, for example, materials. Similarly, the first gelling agent of the first coating liquid, the second gelling agent of the second coating liquid, and the third gelling agent of the third coating liquid may be different from each other. Similarly, the first binder of the first coating liquid and the second binder of the second coating liquid may be different from each other.

  In the above embodiment, the shape of the power storage cell is substantially rectangular when viewed from the direction X, but is not limited thereto. When viewed from the direction X, the shape of the storage cell may be a polygon such as a triangle, a pentagon, or the like, a circle, or an ellipse. Similarly, the shape of each current collecting plate and the like is not limited to the above embodiment. The shapes of the positive electrode current collector and the negative electrode current collector are not limited to the illustrated shapes.

  The example of the step of forming the electrode laminate is not limited to the mode described with reference to FIGS. 6A to 8B. For example, a separator containing a solid or gel electrolyte may be prepared in advance, and the electrode laminate may be formed using the separator.

  The method for manufacturing an all-solid-state battery according to the present invention includes a step of forming a first electrode stacked in an electrode stack, a step of forming a second electrode, and a first electrode, a second electrode, and a gel electrolyte. What is necessary is just to provide the process of forming an electrode laminated body by laminating via a separator.

  In the above embodiment, the power storage cells in the cell stack are connected in parallel, but this is not a limitation. For example, the storage cells may be connected in series. In this case, one connection member functioning as the positive electrode of the power storage device may be connected to one of the plurality of power storage cells included in the cell stack. The other connection member functioning as the negative electrode of the power storage device may be connected to a power storage cell different from the one power storage cell.

  In the above embodiment, the power storage cell, the positive electrode current collector, and the negative electrode current collector are separate from each other, but are not limited thereto. For example, the power storage cell, the positive electrode current collector, and the negative electrode current collector may be integrated with each other. In this case, for example, the holding member may integrate the electrode laminate, the positive electrode current collector, and the negative electrode current collector. Thereby, contact between the electrode laminate, the positive electrode current collector, and the negative electrode current collector can be ensured. The cell stack may include both a unit in which the power storage cell, the positive electrode current collector and the negative electrode current collector are integrated with each other, and a power storage cell in which the positive electrode current collector and the negative electrode current collector are separate bodies. Good. In this case, the units and the storage cells are alternately arranged along the direction X.

  DESCRIPTION OF SYMBOLS 1 ... Power storage device, 2 ... Cell stack, 3 ... Connection member, 4 ... Connection member, 11 ... Power storage cell, 12 ... Positive current collector plate, 13 ... Negative current collector plate, 14 ... Electrode laminated body, 14c ... Outer peripheral surface, Reference numeral 15: holding member, 16: bipolar electrode, 17: separator, 21: current collector, 21a: main surface (first main surface), 21b: main surface (second main surface), 22: positive electrode layer (base layer) , 23 ... negative electrode layer.

Claims (10)

A first coating liquid containing a first ionic liquid, a first gelling agent for gelling the first ionic liquid, a first binder, and a positive electrode active material is applied to the first main surface of the first current collector. After the processing, the first ionic liquid is gelled with the first gelling agent, and the first coating liquid is solidified with the first binder to form the first main surface of the first current collector. Forming a first electrode having a positive electrode layer disposed thereon,
A second coating liquid containing a second ionic liquid, a second gelling agent for gelling the second ionic liquid, a second binder, and a negative electrode active material is applied to the second main surface of the second current collector. After the working, the second ionic liquid is gelled with the second gelling agent, and the second coating liquid is solidified with the second binder to form the second main surface of the second current collector. Forming a second electrode having a negative electrode layer disposed thereon,
The formed first electrode and the second electrode are laminated in one direction so that a separator containing a solid or gel electrolyte is sandwiched between the positive electrode layer of the first electrode and the negative electrode layer of the second electrode. Forming an electrode stack by doing
Comprising,
Manufacturing method of all solid state battery. The step of forming the first electrode includes:
Applying the first coating liquid on the first main surface of the first current collector;
Applying the second coating liquid on a second main surface of the first current collector opposite to the first main surface;
The first ionic liquid in the first coating liquid applied to the first main surface of the first current collector is gelled with the first gelling agent, and the first coating liquid is Solidifying with the first binder to form the positive electrode layer on the first main surface of the first current collector;
The second ionic liquid in the second coating liquid applied to the second main surface of the first current collector is gelled with the second gelling agent, and the second coating liquid is Solidifying with the second binder to form the negative electrode layer on the second main surface of the first current collector;
Has,
The step of forming the second electrode includes:
A step of applying the second coating liquid on the second main surface of the second current collector;
A step of applying the first coating liquid on a first main surface of the second current collector opposite to the second main surface;
The second ionic liquid in the second coating liquid applied to the second main surface of the second current collector is gelled with the second gelling agent, and the second coating liquid is Solidifying with the second binder to form the negative electrode layer on the second main surface of the second current collector;
The first ionic liquid in the first coating liquid applied to the first main surface of the second current collector is gelled with the first gelling agent, and the first coating liquid is Solidifying with the first binder to form the positive electrode layer on the first main surface of the second current collector;
Having,
A method for manufacturing an all-solid-state battery according to claim 1. The first ionic liquid and the second ionic liquid are the same ionic liquid,
The method for manufacturing an all-solid-state battery according to claim 1. The first binder and the second binder are thermosetting resin binders,
By heating the first coating liquid and the second coating liquid, the first coating liquid and the second coating liquid are solidified,
A method for manufacturing the all-solid-state battery according to claim 1. The first binder and the second binder are the same binder,
A method for manufacturing the all-solid-state battery according to claim 1. The step of forming the electrode laminate,
A third ionic liquid, a third gelling agent for gelling the third ionic liquid, on an underlayer that is one of the positive electrode layer of the first electrode or the negative electrode layer of the second electrode; Applying a third coating solution containing the first binder,
The third coating liquid applied is sandwiched between the base layer and a layer having a polarity opposite to that of the base layer in the positive electrode layer of the first electrode or the negative electrode layer of the second electrode. Disposing the first electrode and the second electrode;
The third ionic liquid is gelled with the third gelling agent, and the third coating solution disposed between the first electrode and the second electrode is solidified with the first binder, Forming the separator between a first electrode and the second electrode;
Having,
A method for manufacturing the all-solid-state battery according to claim 5. Further comprising a step of forming a holding member for holding the first electrode and the second electrode on the outer peripheral surface of the electrode stack to obtain a power storage cell;
A method for manufacturing the all-solid-state battery according to claim 1. Adjacent to the power storage cell in the one direction, and further comprising a step of disposing a current collector plate in the power storage cell so as to be electrically connected to the power storage cell,
A method for manufacturing the all-solid-state battery according to claim 7. Bipolar having a current collector, a positive electrode layer disposed on a first main surface of the current collector, and a negative electrode layer disposed on a second main surface of the current collector opposite to the first main surface Forming an electrode;
A step of forming an electrode laminate by laminating the formed plurality of bipolar electrodes in one direction via a separator containing a solid or gel electrolyte,
With
The step of forming the bipolar electrode,
Applying a first coating solution containing an ionic liquid, a gelling agent for gelling the ionic liquid, a binder and a positive electrode active material on the first main surface of the current collector;
A step of applying a second coating liquid containing the ionic liquid, the gelling agent, the binder, and the negative electrode active material on the second main surface of the current collector;
The ionic liquid in the first coating liquid applied to the first main surface is gelled with the gelling agent, and the first coating liquid is solidified to form the first coating liquid on the first main surface. Forming the positive electrode layer;
The ionic liquid in the second coating liquid applied to the second main surface is gelled with the gelling agent, and the second coating liquid is solidified to form the second coating liquid on the second main surface. Forming the negative electrode layer;
Having,
Manufacturing method of all solid state battery. A first electrode in which a positive electrode layer including a gel electrolyte, a positive electrode active material, and a thermosetting resin binder is disposed on at least one main surface of the first current collector;
A second electrode in which a negative electrode layer including a gel electrolyte, a negative electrode active material, and the resin binder is disposed on at least one main surface of the second current collector;
A separator that is disposed between the first electrode and the second electrode and is sandwiched between the positive electrode layer and the negative electrode layer, and includes a solid or gel electrolyte and the binder.
Comprising,
All solid state battery.

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