Method for manufacturing power storage device, recording apparatus, and apparatus for manufacturing power storage device

Abstract

The invention relates to a method for manufacturing a power storage device, a recording apparatus, and an apparatus for manufacturing a power storage device, which solve the problem that individual differences of electrode materials for cells cannot be predicted in advance or understood afterwards. A first code (18) is formed along the longitudinal direction in an unformed region (16a) of a current collector (16) of a lithium ion secondary battery (10). The first inspection device (105) and the second inspection device (107) record inspection information in a recording device (210) while specifying the position of the active material layer (17) using the first code (18). As a result, inspection information of the active material layer (17) corresponding to the position of the first code (18) can be acquired afterwards in the longitudinal direction of the current collector (16), and individual differences in electrode materials for cells can be predicted or ascertained afterwards.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing an electric storage device, a recording device, and an apparatus for manufacturing an electric storage device. Background Art

[0002] In Japanese Patent Publication No. 2015-167078, a method for manufacturing an electrode formed by cutting an electrode material having a coating portion of an active material composite material and an exposed portion of the metal foil on at least one side of a long strip of metal foil is disclosed. In this manufacturing method, a strip body is formed by cutting the electrode material into a strip shape. The electrode is manufactured by overlapping a plurality of the strip bodies. In this manufacturing method, the coating portion of the electrode material is checked to check whether there is a defective portion in the coating portion. When there is a defective portion in the coating portion, a mark is added to the exposed portion. When the electrode material is cut, by detecting the mark using a mark detection device, it is possible to determine whether there is a defective portion in the coating portion. The portion of the electrode material that includes the coating portion that is judged to have a defective portion is not cut into a strip body and is not used for the manufacture of the electrode. In addition, the mark is added outside the area of ​​the electrode material that is cut as a strip body, so the mark is not included in the strip body. As a result, the electrode can be manufactured using only the strip body that does not include a defective portion in the coating portion.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-167078 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In the above-mentioned electrode manufacturing method, in the coating process of the active material composite material, the thickness of the active material composite material is not completely uniform. Therefore, in the final assembled unit, individual differences occur in the electrode materials used in the unit. This individual difference cannot be predicted in advance or grasped afterwards.

[0008] Means for solving problems

[0009] The manufacturing method of the energy storage device disclosed herein includes: a process of adding a first identifier for determining the position in the strip-shaped current collector to a pre-set unformed area along the length direction of the strip-shaped current collector at predetermined intervals; a process of forming an active material layer on a portion of the strip-shaped current collector other than the unformed area; and an inspection process, in which inspection information is recorded, the inspection information being obtained by determining the position of the strip-shaped current collector in association with the first identifier while inspecting the state of the active material layer.

[0010] According to this method of manufacturing an electric storage device, it is possible to acquire afterward the inspection information of the active material layer corresponding to the position to which the first identifier is added in the longitudinal direction of the current collector. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a perspective view of the lithium ion secondary battery 10 .

[0012] Figure 2 It is along Figure 1 A schematic longitudinal cross-sectional view along line II-II.

[0013] Figure 3 is a schematic diagram of the electrode body 20 .

[0014] Figure 4 (a) to (f) are schematic diagrams of the manufacturing process of the electrode sheet 15 .

[0015] Figure 5 It is a schematic diagram of the manufacturing apparatus 1 of the electric storage device.

[0016] Figure 6 It is a diagram showing an example of the database DT constructed by the recording device 210.

[0017] Figure 7 1 is a flowchart showing a method for manufacturing the lithium ion secondary battery 10 .

[0018] Figure 8 is shown with Figure 7 The flowchart shown is a flowchart of a method for manufacturing the lithium ion secondary battery 10 in different procedures.

[0019] Description of Reference Numerals

[0020] 1. Manufacturing apparatus for electric storage device

[0021] 1a code is given to the production line

[0022] 1b Electrode manufacturing production line

[0023] 10 Lithium-ion secondary batteries (electricity storage devices)

[0024] 15 Electrode sheet

[0025] 16 Current Collector

[0026] 16a Unformed area

[0027] 16aa Tab formation area

[0028] 16ab code marking area

[0029] 17 Active material layer

[0030] 18 First code (first identifier)

[0031] 19 Second code (second identifier)

[0032] 20 Electrode body

[0033] 21. Positive electrode

[0034] 21a Positive electrode collector

[0035] 21a1 Unformed part

[0036] 21b Positive electrode active material layer

[0037] 21p positive electrode protection layer

[0038] 21t positive electrode tab

[0039] 22 Negative electrode

[0040] 22a Negative electrode collector

[0041] 22a1 Unformed part

[0042] 22b Negative electrode active material layer

[0043] 22p negative electrode protection layer

[0044] 22t negative electrode tab

[0045] 31, 32 Diaphragm

[0046] 41 Battery housing

[0047] 41a Housing body

[0048] 41a1 Opening

[0049] 41b Sealing plate

[0050] 41b1 Filling hole

[0051] 41b2 Sealing member

[0052] 41b3 Safety valve

[0053] 42 bottom part

[0054] 43, 44 wide face

[0055] 45, 46 Narrow face

[0056] 50 Positive terminal

[0057] 51, 61 external terminals

[0058] 55, 65 internal terminals

[0059] 60 Negative terminal

[0060] 61 External terminals

[0061] 70 Washer

[0062] 80 Insulator

[0063] 100, 104 unwinding roller

[0064] 101 Laser marking device

[0065] 102 Coating device

[0066] 103, 111 take-up roller

[0067] 106 Compression device

[0068] 106a, 106b rolling rollers

[0069] 108 Half-cut device

[0070] 109 Cutting device

[0071] 110 Laser marking device

[0072] 120 Roller

[0073] 150 Conveyor

[0074] 200 Control device

[0075] 210 Recording Device

[0076] CL cutting line

[0077] DT Database

[0078] S1 First identifier assignment step

[0079] S2 coating process

[0080] S3 First inspection process

[0081] S4 Compression process

[0082] S5 Second inspection process

[0083] S6 Half-cutting process

[0084] S7 Tab Cutting Process

[0085] S8 Second identifier assigning step

[0086] S9 Winding process

[0087] S10 Assembly process DETAILED DESCRIPTION

[0088] The disclosure herein is described below. Unless otherwise specified, the disclosure herein is not intended to limit the invention described in the claims of the present application. The drawings are schematically depicted and may not reflect the actual objects. In addition, components and parts that play the same role are appropriately marked with the same figure marks, and repeated descriptions are omitted. In this specification, unless otherwise specified, expressions such as "X~Y" indicating a numerical range mean "above X and below Y".

[0089] The disclosure herein relates to a method for manufacturing an electrical storage device. In the method for manufacturing an electrical storage device disclosed herein, for example, a lithium-ion secondary battery is manufactured. In an electrode body of the lithium-ion secondary battery, for example, a positive electrode current collector is aluminum or an aluminum alloy, and a negative electrode current collector is copper or a copper alloy.

[0090] <Lithium-ion secondary battery 10>

[0091] Figure 1 It is a perspective view of the lithium-ion secondary battery 10 . Figure 2 It is along Figure 1 A schematic longitudinal cross-sectional view taken along line II-II. Figure 3 is a schematic diagram of the electrode body 20. Figure 2 , a state in which the interior of the lithium-ion secondary battery 10 is exposed along a wide surface of one side of a substantially rectangular parallelepiped battery case 41 is depicted. Figure 2 , the electrode body 20 is further illustrated in a partially cut-away partial cross-sectional view. Figure 2 The lithium-ion secondary battery 10 shown is a so-called sealed battery in which a battery case 41 containing an electrode body 20 is sealed. In the present embodiment, the battery case 41 is composed of a substantially rectangular square metal case. The reference symbol X in the drawings indicates the long side direction of the battery case 41. The reference symbol Y (see Figure 1 ) represents the short side direction orthogonal to the long side direction. Reference symbol Z represents the height direction orthogonal to the short side direction and the long side direction. The structure of the battery case 41 is not limited to this method. For example, the battery case 41 can be a cylindrical case or a so-called bag-shaped laminated case covering the electrode body 20.

[0092] like Figure 2As shown, the lithium-ion secondary battery 10 includes an electrode body 20 and a battery case 41. The battery case 41 includes: a case body 41a, the case body 41a having an opening 41a1; and a sealing plate 41b, the sealing plate 41b sealing the opening 41a1 of the case body 41a. The case body 41a accommodates the electrode body 20. On the sealing plate 41b, internal terminals 55, 65 and external terminals 51, 61 are installed via a gasket 70 and an insulator 80. In the present embodiment, the internal terminal 55 is connected to the positive electrode collector 21a of the electrode body 20. The external terminal 51 is connected to the internal terminal 55 to form a positive electrode terminal 50 on the outside of the battery case 41. In addition, the internal terminal 65 is connected to the negative electrode collector 22a (see Figure 3 The external terminal 61 is connected to the internal terminal 65 to form a negative electrode terminal 60 outside the battery case 41.

[0093] <Electrode body 20>

[0094] like Figure 3 As shown, in the electrode body 20, the positive electrode element 21 and the negative electrode element 22 face each other with a separator therebetween. The positive electrode element 21 includes a positive electrode collector 21a and a positive electrode active material layer 21b formed on the positive electrode collector 21a and containing a positive electrode active material. The negative electrode element 22 includes a negative electrode collector 22a and a negative electrode active material layer 22b formed on the negative electrode collector 22a and containing a negative electrode active material. The positive electrode element 21 and the negative electrode element 22 can be in the form of sheets, respectively. In this case, the positive electrode element can be, for example, a sheet-like component in which the positive electrode active material layer 21b is formed on both sides of the positive electrode collector 21a composed of a metal foil of a predetermined width and thickness. The negative electrode element can be a sheet-like component in which the negative electrode active material layer 22b is formed on both sides of the negative electrode collector 22a composed of a metal foil of a predetermined width and thickness. The sheet-like positive electrode element 21 is called a positive electrode sheet. The sheet-like negative electrode is called the negative electrode sheet.

[0095] For example, the electrode body 20 may be a so-called wound electrode body. The electrode body 20 is composed of a positive electrode sheet 21 as a positive electrode element, a negative electrode sheet 22 as a negative electrode element, and separator sheets 31 and 32 as separators. The positive electrode sheet 21, the first separator sheet 31, the negative electrode sheet 22, and the second separator sheet 32 ​​are respectively long strip-shaped members, which are overlapped and wound in a consistent manner in the length direction and the width direction. The electrode body 20 is accommodated in the battery case 41 in a state covered by an insulating film (not shown) or the like.

[0096] The positive electrode sheet 21 and the negative electrode sheet 22 are formed, for example, by cutting an electrode sheet wound into a roll. Figure 4 As shown in FIG. 2 ( b ), the electrode sheet 15 includes a current collector 16 and an active material layer 17 . Figure 4(a) to (f) are schematic diagrams of the manufacturing process of the electrode sheet 15. Figure 4 (a) ~ Figure 4 The details of (f) will be described later.

[0097] The current collector 16 is a long strip-shaped metal member. As the current collector 16, a metal material having the required conductivity can be used. As the positive electrode current collector, for example, aluminum, aluminum alloy, etc. can be used. As the negative electrode current collector, for example, copper, copper alloy, etc. can be used. An active material layer 17 is formed on at least one side of the strip-shaped current collector 16. In the present embodiment, an active material layer 17 is formed on a single side of the current collector 16. The active material layer 17 is a layer containing an electrode active material. As the positive electrode active material, for example, a lithium transition metal composite oxide can be used. As the negative electrode active material, for example, a carbon material, a silicon-based material, and a mixed oxide thereof can be used. The electrode active material layer may contain additives other than the electrode active material such as a binder and a conductive material.

[0098] The electrode sheet 15 is formed by applying an electrode composite material slurry to become an active material layer 17 to a current collector 16 and drying the slurry. The electrode composite material slurry is a paste-like slurry formed by mixing a positive electrode active material or a negative electrode active material, a conductive material, a binder, etc. in a solvent. The electrode composite material slurry is applied by a coating device 102 (see Figure 5 ) is applied. An unformed region 16a is set on the current collector 16. The unformed region 16a is arranged at a predetermined position along the length direction of the current collector 16. In the present embodiment, the unformed region 16a is set at both ends of the width direction of the current collector 16. The electrode composite material slurry is applied to the portion other than the unformed region 16a relative to the current collector 16. Thus, the active material layer 17 is formed on the portion of the current collector 16 other than the unformed region 16a.

[0099] 〈Positive electrode 21〉

[0100] The positive electrode sheet 21 is formed by using a positive electrode current collector as the current collector 16 and forming a positive electrode active material layer as the active material layer 17 in the above-mentioned electrode sheet 15. Figure 3 As shown, the positive electrode sheet 21 has a positive electrode current collector 21a of a predetermined width and thickness, and a positive electrode active material layer 21b containing a positive electrode active material is formed on one side, except for an unformed portion 21a1 set with a certain width at one end of the width direction. In the unformed portion 21a1, a plurality of positive electrode tabs 21t are intermittently provided at predetermined positions along the length direction of the positive electrode sheet 21. The plurality of positive electrode tabs 21t protrude in the width direction of the positive electrode sheet 21, respectively.

[0101] For example, in the lithium-ion secondary battery 10, the positive electrode active material layer 21b releases lithium ions during charging and absorbs lithium ions during discharging. Examples of the positive electrode active material include lithium transition metal composite materials. Various schemes have been proposed for the positive electrode active material in addition to the lithium transition metal composite material, and unless otherwise specified, it is not limited to the lithium transition metal composite material. The positive electrode active material layer 21b can be a structure formed by coating the electrode composite material slurry and drying it. In addition, in the present embodiment, a positive electrode protective layer 21p is provided on the positive electrode collector 21a (unformed portion 21a1) at the edge of the positive electrode active material layer 21b. The positive electrode protective layer 21p is a layer that protects the unformed portion 21a1 and can be a layer containing an inorganic filler (e.g., alumina).

[0102] 〈Negative electrode sheet 22〉

[0103] The negative electrode sheet 22 uses a negative electrode collector as the collector 16 in the above-mentioned electrode sheet 15, and forms a negative electrode active material layer as the active material layer 17. The negative electrode sheet 22 has a negative electrode collector 22a of a predetermined width and thickness, and a negative electrode active material layer 22b containing a negative electrode active material is formed on one side, except for an unformed portion 22a1 set with a certain width at the edge of one side in the width direction. In this embodiment, in the unformed portion 22a1, a plurality of negative electrode tabs 22t are intermittently provided at predetermined positions along the length direction of the negative electrode sheet 22. The plurality of negative electrode tabs 22t protrude in the width direction of the negative electrode sheet 22, respectively. In this embodiment, the positions of the plurality of negative electrode tabs 22t are determined in such a way that the positions of the plurality of negative electrode tabs 22t are aligned in the wound state.

[0104] Considering the working potential in the negative electrode, the negative electrode collector 22a uses a material with the required resistance to electrolyte, oxidation resistance, etc. For example, in the lithium ion secondary battery 10, the negative electrode collector 22a usually uses copper or a copper alloy with copper as the main material. In the sheet-shaped negative electrode element 22, the negative electrode collector 22a can use copper or copper foil with copper as the main material. The negative electrode active material contained in the negative electrode active material layer 22b uses a material that can absorb and store charge carriers during charging and release charge carriers during discharge. For example, in a lithium ion secondary battery, it is a material that can absorb and store lithium ions during charging and release the lithium ions absorbed and stored during discharge, such as natural graphite. In addition to natural graphite, various schemes are generally proposed for the negative electrode active material, which is not particularly limited. The negative electrode active material layer 22b can be, for example, a structure formed by coating and drying in the state of a composite material formed by mixing such a negative electrode active material, a conductive material, and a binder in a solvent.

[0105] The diaphragm sheets 31 and 32 use, for example, porous resin sheets that have the required heat resistance and through which an electrolyte can pass. Various proposals have been proposed for the diaphragm sheets 31 and 32, and there is no particular limitation. The diaphragm sheets 31 and 32 may have functional layers such as an adhesive layer and a heat-resistant layer (HRL) on the surface of a substrate composed of a porous sheet made of resin. The heat-resistant layer is, for example, a layer containing inorganic fillers such as alumina, silica, boehmite, magnesium oxide, and titanium dioxide, and a binder such as PVdF. The heat-resistant layer may also serve as an adhesive layer.

[0106] Here, if Figure 3 As shown in FIG. 1 , the width Ln of the negative electrode active material layer 22b is formed to be wider than the width Lp of the positive electrode active material layer 21b. The width Ls of the separator sheets 31 and 32 is wider than the negative electrode active material layer 22b. Figure 3 As shown, Lp<Ln<Ls. The positive electrode sheet 21, the first separator sheet 31, the negative electrode sheet 22 and the second separator sheet 32 ​​are aligned in the length direction and are overlapped and wound in sequence. Here, the negative electrode active material layer 22b covers the positive electrode active material layer 21b in a state of sandwiching the separator sheets 31 and 32. The negative electrode active material layer 22b is covered by the separator sheets 31 and 32. The positive electrode tab 21t of the positive electrode collector 21a and the negative electrode tab 22t of the negative electrode collector 22a are arranged in a manner that they extend from the separator sheets 31 and 32 toward opposite sides in the width direction. The positive electrode protective layer 21p faces the edge of the negative electrode sheet 22 on the side opposite to the side where the negative electrode tab 22t is provided, separated by the separator sheets 31 and 32.

[0107] like Figure 2 As shown, the electrode assembly 20 is arranged along a direction including a winding axis WL (see FIG. 1 ) so as to be accommodated in a case body 41 a of a battery case 41. Figure 3 ) in a flat state of a plane. And, along the winding axis WL of the electrode body 20, a positive electrode tab 21t is arranged on one side, and a negative electrode tab 22t is arranged on the opposite side. In addition, here, as the electrode body 20, a wound electrode body formed by overlapping and winding a positive electrode sheet 21, a first diaphragm sheet 31, a negative electrode sheet 22, and a second diaphragm sheet 32 ​​is exemplified. The structure of the electrode body 20 is not limited to such a wound electrode body. Although the illustration is omitted, the electrode body 20 may also be a so-called stacked electrode body in which a positive electrode sheet and a negative electrode sheet of a predetermined shape are overlapped with a diaphragm sheet sandwiched therebetween.

[0108] <Battery Case 41>

[0109] The battery case 41 accommodates the electrode body 20. In the present embodiment, the battery case 41 has a case body 41a and a sealing plate 41b. The case body 41a is a member with a bottom having an opening 41a1 on a side facing the bottom surface, and in the present embodiment, has a substantially rectangular square shape with one side opening. The sealing plate 41b is a plate material mounted on the opening 41a1 of the case body 41a. In the present embodiment, from the viewpoint of ensuring lightweight and required rigidity, the case body 41a and the sealing plate 41b are respectively formed of aluminum or an aluminum alloy mainly composed of aluminum.

[0110] The battery case 41 can accommodate an electrolyte (not shown). As the electrolyte, a non-aqueous electrolyte in which a supporting salt is dissolved in a non-aqueous solvent can be used. As an example of a non-aqueous solvent, carbonate-based solvents such as ethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate can be cited. As an example of a supporting salt, a fluorine-containing lithium salt such as LiPF6 can be cited.

[0111] <Casing body 41a>

[0112] like Figure 2 As shown, the housing body 41a has a substantially rectangular parallelepiped square shape with one side opening. The housing body 41a has a bottom surface 42 constituting a substantially rectangular bottom surface, a pair of wide surface portions 43 and 44 (see Figure 1 ) and a pair of narrow width surfaces 45, 46. The pair of wide width surfaces 43, 44 respectively stand up from the long sides of the bottom surface 42. The pair of narrow width surfaces 45, 46 respectively stand up from the short sides of the bottom surface 42. An opening 41a1 surrounded by the pair of wide width surfaces 43, 44 and the pair of narrow width surfaces 45, 46 is formed on one side of the housing body 41a.

[0113] <Sealing plate 41b>

[0114] The sealing plate 41b seals the opening 41a1 of the housing body 41a. Figure 1 As shown, the sealing plate 41b is rectangular in plan view. In this embodiment, the sealing plate 41b is provided with a liquid injection hole 41b1 and a safety valve 41b3. The liquid injection hole 41b1 is closed by installing a sealing member 41b2 after the sealing plate 41b is installed on the opening 41a1 of the housing body 41a and the electrolyte is injected into the housing body 41a. Figure 2 4 shows a state where the sealing plate 41b is assembled to the opening 41a1 of the housing body 41a and welded. Figure 2 In the embodiment, the sealing member 41b2 is not attached to the sealing plate 41b. The safety valve 41b3 is a thin-walled portion that breaks when the pressure in the battery case 41 exceeds a predetermined pressure.

[0115] like Figure 2As shown, a positive terminal 50 and a negative terminal 60 are installed on the sealing plate 41b. The positive terminal 50 includes an external terminal 51 and an internal terminal 55. The negative terminal 60 includes an external terminal 61 and an internal terminal 65. The internal terminals 55 and 65 are respectively installed on the inner side of the sealing plate 41b via an insulator 80. The external terminals 51 and 61 are respectively installed on the outer side of the sealing plate 41b via a gasket 70. The internal terminals 55 and 65 extend to the inside of the shell body 41a. The unformed portion 21a1 of the positive electrode collector 21a of the electrode body 20 and the unformed portion 22a1 of the negative electrode collector 22a are installed on the internal terminals 55 and 65 respectively installed on both sides of the long side direction of the sealing plate 41b.

[0116] The internal terminals 55 and 65 are made of metal. As the internal terminal 55 of the positive electrode, aluminum, aluminum alloy, etc. can be used from the viewpoint of improving the bonding strength with the positive electrode tab 21t. As the internal terminal 65 of the negative electrode, copper, copper alloy, etc. can be used from the viewpoint of improving the bonding strength with the negative electrode tab 22t and from the viewpoint of having the required resistance such as electrolyte resistance and oxidation resistance.

[0117] The external terminals 51 and 61 are made of metal. The metal used as the external terminals 51 and 61 is appropriately selected according to the type of external connection parts such as busbars. As the external terminals 51 and 61, for example, aluminum, aluminum alloy, copper, copper alloy, etc. can be used. The external terminals 51 and 61 can also be composed of, for example, multiple metals joined by dissimilar metal joining. Although omitted in the figure, a mounting hole is formed in the sealing plate 41b. In the mounting hole, an insulator 80 is installed on the inner side of the sealing plate 41b, and a gasket 70 is installed on the outer side of the sealing plate 41b. An axis portion is provided on one of the internal terminals 55 and 65 and the external terminals 51 and 61, and the gasket 70 and the insulator 80 are inserted into the mounting hole. The internal terminals 55 and 65 are joined to the external terminals 51 and 61 by the axis portion inserted into the mounting hole.

[0118] The gasket 70 and the insulator 80 can be made of materials with excellent chemical resistance and weather resistance. In the present embodiment, the gasket 70 uses tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA). In addition, the material used for the gasket 70 is not limited to PFA. For example, polypropylene (PP), polyethylene (PE), polyphenylene sulfide resin (PPS), etc. can be used for the gasket 70. Polyphenylene sulfide resin (PPS) is used for the insulator 80. In addition, the material used for the insulator 80 is not limited to PPS.

[0119] When manufacturing the lithium-ion secondary battery 10, the positive terminal 50 and the negative terminal 60 are installed in a state where the gasket 70 and the insulator 80 are installed on the sealing plate 41b. Next, the positive electrode tab 21t is connected to the internal terminal 55 of the positive terminal 50, and the negative electrode tab 22t is connected to the internal terminal 65 of the negative terminal 60, thereby installing the electrode body 20 on the sealing plate 41b. Next, the electrode body 20 is inserted into the case body 41a from the opening 41a1, and the sealing plate 41b is installed in the opening 41a1 of the case body 41a (see Figure 1 At this time, the winding axis WL of the electrode body 20 (see Figure 3 ) is arranged along the longitudinal direction X of the shell body 41a. The positive electrode tab 21t of the electrode body 20 faces the narrow width surface 45. The negative electrode tab 22t faces the narrow width surface 46. And, as Figure 2 As shown, the peripheral edge of the sealing plate 41b is joined to the edge of the opening 41a1 of the housing body 41a. This joining may be, for example, continuous welding without a gap. This welding may be achieved, for example, by laser welding.

[0120] A plurality of electrode bodies 20 can be accommodated in the battery case 41. Various structures can be adopted for the internal terminals 55, 65, the external terminals 51, 61, the gasket 70, and the insulator 80. For example, the internal terminals 55, 65, the external terminals 51, 61, the gasket 70, and the insulator 80 can adopt appropriate structures according to the structure of the electrode body 20 accommodated. In addition, a mechanism (CID (Current Interrupt Device)) that cuts off the current when the internal pressure rises due to the generation of gas inside during overcharging can also be provided on one of the positive terminal 50 and the negative terminal 60.

[0121] The structure of the lithium ion secondary battery 10 to be manufactured has been described above.

[0122] In addition, the positive electrode sheet 21 and the negative electrode sheet 22 are formed by, for example, applying an active material composite material to a long strip-shaped current collector 16. In the manufacture of the cell, the electrode sheet 15 of a desired length is cut from the long strip-shaped electrode sheet 15 and assembled to the electrode body 20. The inventors of the present invention believe that if the thickness of the active material layer 17 along the length direction of the electrode sheet 15 used for the cell can be known afterward during or after the cell assembly, the quality of the electrode body 20 when assembled can be improved or individual differences of the battery can be predicted.

[0123] Therefore, the present inventors considered including the following steps in the method for manufacturing an electric storage device.

[0124] Step A: A step of adding first codes 18 for specifying positions in the strip-shaped current collector 16 to pre-set unformed regions 16 a along the longitudinal direction of the strip-shaped current collector 16 at pre-set intervals.

[0125] Step B: a step of forming the active material layer 17 on the portion of the strip-shaped current collector 16 excluding the non-formed region 16 a .

[0126] Step C: an inspection step of recording inspection information obtained by inspecting the state of active material layer 17 while identifying the position of strip-shaped current collector 16 in association with first code 18 .

[0127] According to the manufacturing method of the power storage device, it is possible to obtain inspection information of the active material layer 17 corresponding to the position to which the first code 18 is added in the longitudinal direction of the current collector 16. Therefore, when assembling the cell or after assembling the cell, it is possible to know the thickness of the active material composite material along the longitudinal direction of the electrode sheet 15 used in the cell. Therefore, for example, individual differences in the electrode material used in the cell can be predicted or known in advance.

[0128] As mentioned above, Figure 4 (a) to (f) are schematic diagrams of the manufacturing process of the electrode sheet 15 . Figure 4 (a) is a diagram showing a process of adding a first code 18 for specifying a position in the strip-shaped current collector 16 to a pre-set unformed region 16a along the longitudinal direction of the strip-shaped current collector 16 at a predetermined interval. Here, the cutting line CL indicated by a double-dashed line is a diagram showing the process of forming the tabs 21t and 22t (see Figure 3 ) is cut at the position of the cutting position. In addition, in this specification, the case where the tabs 21t and 22t are formed by cutting along the cutting line CL is referred to as tab cutting. The details of the first code 18 will be described later. Figure 4 (b) is a diagram showing a step of forming the active material layer 17 on the portion of the strip-shaped current collector 16 excluding the unformed region 16a. Figure 4 In the state (b), inspection information obtained by inspecting the state of the active material layer 17 while identifying the position of the strip-shaped current collector 16 in association with the first code 18 is recorded. Figure 4 (c) shows that Figure 4 FIG. 1 is a diagram showing a step of cutting the electrode sheet 15 in half in the width direction from the state (b).

[0129] Here, the unformed region 16a includes a tab formation region 16aa and a code engraved region 16ab. The tab formation region 16aa is formed by cutting off the code engraved region 16ab in the unformed region 16a to form tabs 21t and 22t described later (see Figure 3 ) area. A first code 18 is formed in the code engraving area 16ab. The first code 18 is an example of a first identifier in the present invention. The first code 18 is, for example, a two-dimensional code such as a QR code (registered trademark). In addition, the first code 18 may also be, for example, a one-dimensional code (barcode). Here, the one-dimensional code is formed with a plurality of straight lines extending in one direction. Therefore, when forming a one-dimensional code, it is necessary to form it while appropriately stopping the conveyance of the electrode sheet 15, which is inefficient. Therefore, the first code 18 may be a one-dimensional code, but is preferably a two-dimensional code. Alternatively, the first identifier may also be a specified mark, etc.

[0130] The first code 18 is assigned at predetermined intervals along the length direction of the electrode sheet 15. The first code 18 is formed, for example, by a laser. In the present embodiment, the first code 18 is assigned, for example, every 1 m along the length direction of the electrode sheet 15. The first code 18 is assigned to the code engraving area 16ab. The first code 18 has information for determining the position where the first code 18 is formed in the collector 16. The information for determining the position where the first code 18 is formed in the collector 16 is referred to as identification information. The identification information is, for example, a continuous number such as 0, 1, 2, 3... registered in sequence from the first code 18 attached to the front end of the electrode sheet 15.

[0131] Furthermore, the present inventors considered including the following steps in the method for manufacturing an electric storage device.

[0132] Step D: a tab cutting process step in which the tab is cut in the unformed region 16 a while the first code 18 of the strip-shaped current collector 16 is read to identify the position of the strip-shaped current collector 16 .

[0133] Step E: A step of adding the second code 19 to predetermined positions of the tabs 21 t and 22 t formed in the tab cutting process.

[0134] Step F: A winding step of reading the second code 19 and winding the strip-shaped current collector 16 that has been subjected to the tab cutting process.

[0135] Figure 4 (d) is a schematic diagram showing a tab cutting process step of performing tab cutting in the unformed region 16 a . Figure 4 (e) is a schematic diagram showing a step of adding the second code 19 to predetermined positions of the tabs 21 t and 22 t formed in the tab cutting process. Figure 4(f) is a diagram showing the process of reading the second code 19 and winding up the strip-shaped current collector 16 that has been subjected to the tab cutting process.

[0136] The second code 19 is assigned at a predetermined interval along the length direction of the electrode sheet 15. The second code 19 is an example of a second identifier in the present invention. The second code 19 is attached to the predetermined position of the tabs 21t and 22t formed by tab cutting. That is, the second code 19 is assigned to the tab formation area 16aa. The second code 19 has identification information in the same manner as the first code 18. In addition, the second code 19 is associated with the identification information of all the first codes 18 contained in the positive electrode sheet 21 and the negative electrode sheet 22. The second code is, for example, a two-dimensional code such as a QR code (registered trademark). However, like the first code 18, it can also be a one-dimensional code.

[0137] Furthermore, the present inventors considered including the following steps in the method for manufacturing an electric storage device.

[0138] Step G: a step of housing the electrode assembly 20 in the battery case 41 while reading the second code 19 of the electrode assembly 20 obtained in the winding step.

[0139] Step H: a step of obtaining a unique number added to the battery case 41 .

[0140] Step I: a step of recording the unique number of the battery case 41 and the second code of the electrode assembly 20 housed in the battery case 41 in association with each other.

[0141] Here, the battery case 41 in this embodiment (see Figure 2 ) is assigned a unique number. The unique number is a number that can identify the battery case 41 one by one, for example, a unique number determined according to the year, month, and day of manufacture and the order of manufacture. Although not shown in the figure, for example, the unique number is engraved on the outer surface of the battery case 41. The unique number is read by a camera, for example. The unique number can be assigned to the battery case 41 in advance, or it can be assigned by the manufacturing device 1 of the storage device described later. However, the method of identifying the battery case 41 is not limited to this. In order to identify the battery case 41, for example, a unique bar code or the like can be printed.

[0142] <Electricity storage device manufacturing apparatus 1>

[0143] Figure 5 Schematic diagram of a manufacturing apparatus 1 for an electric storage device. The manufacturing method of the electric storage device can be Figure 5 The manufacturing device 1 of the power storage device shown in FIG. Figure 5 Here, the manufacturing apparatus 1 for the storage device manufactures a lithium-ion secondary battery 10 (see Figure 1). The manufacturing device 1 of the storage device includes a code imparting production line 1a and an electrode manufacturing production line 1b. The code imparting production line 1a includes a winding roll 100, a first laser engraving device 101, a coating device 102, and a winding roll 103. The electrode manufacturing production line 1b includes a winding roll 104, a first inspection device 105, a compression device 106, a second inspection device 107, a half-cutting device 108, a cutting device 109, a second laser engraving device 110, and a winding roll 111. In addition, the manufacturing device 1 of the storage device includes a control device 200, and the control device 200 is connected to each device 100~111.

[0144] The electrode sheet 15 is wound around the unwinding rollers 100 and 104. The electrode sheet 15 is transported along a predetermined conveying path and is wound around the winding rollers 103 and 111. The unwinding rollers 100 and 104 and the winding rollers 103 and 111 may also be respectively installed on an automatic splicing device that switches between the unwinding and winding-up rollers and new rollers. In the present embodiment, the unwinding roller 100 and the winding roller 103 are driven by the conveying device 150. The unwinding roller 104 and the winding roller 111 are driven by the conveying device 170. In addition, although detailed illustrations are omitted, in the manufacturing device 1 of the storage battery device, a guide roller 120 is arranged along a predetermined conveying path, and the electrode sheet 15 is conveyed along the conveying path. Although illustrations are omitted, for example, guide rollers, tension adjustment rollers, feed rollers, etc. may be appropriately arranged on the conveying path. The transport device 150 , the various devices 100 to 111 incorporated in the electrical storage device manufacturing apparatus 1 , the transport device 170 , and the like are each configured to be controlled by the control device 200 .

[0145] In addition, in the present embodiment, sensors (not shown) for reading the first code 18 are respectively provided in the coating device 102, the first inspection device 105, the second inspection device 107, the half-cutting device 108, the second laser engraving device 110 and the winding roller 111. In addition, the sensor is also installed near the unwinding roller 104, and the sensor is connected to the compression device 106 and the cutting device 109 by wire or wirelessly. In addition, the sensor can be implemented by a camera, for example. In addition, the manufacturing device 1 of the storage battery device has a winding device (not shown) and an assembling device (not shown) on the downstream side of the winding roller 111. The winding device is used to wind the positive electrode sheet 21, the negative electrode sheet 22 and the diaphragm sheets 31 and 32 (refer to Figure 2 ) is a device for manufacturing an electrode body 20 by overlapping and winding. In addition, the assembly device may also include a sensor for reading the first code 18. The assembly device is a device for storing the manufactured electrode body 20 in a battery case 41 (refer to Figure 1 ) and performs electrolyte injection and the like to manufacture a lithium ion secondary battery 10. However, the assembling method using the winding device and the assembling device is the same as the known technology, and thus is omitted from the illustration.

[0146] <Conveying Devices 150, 170>

[0147] The conveying devices 150 and 170 respectively convey the electrode sheet 15. Although not particularly limited, the conveying speed of the electrode sheet 15 can be set to about 10m / min to 160m / min in the code assignment production line 1a and the electrode manufacturing production line 1b. In this embodiment, a motor is used as the conveying devices 150 and 170. The conveying devices 150 and 170 drive the rotation of the unwinding rollers 100, 104 and the winding rollers 103, 111 in a manner that can convey the electrode sheet 15 at a predetermined conveying speed. The rotation speed of the unwinding rollers 100, 104 and the winding rollers 103, 111 driven by the conveying device 150 can also be controlled by the control device 200. The rotation speed of the unwinding rollers 100, 104 and the winding rollers 103, 111 can be controlled according to a predetermined program so that the conveying speed of the electrode sheet 15 becomes constant. The rotation speeds of the unwinding rollers 100, 104 and the winding rollers 103, 111 can be controlled, for example, according to the amount of the electrode sheet 15 wound around the unwinding rollers 100, 104 and the winding rollers 103, 111. The electrical storage device manufacturing apparatus 1 may include a stepped roller or the like.

[0148] <First Laser Marking Device 101>

[0149] The first laser engraving device 101 is a device for forming a first code 18 on the electrode sheet 15. The first laser engraving device 101 is an example of a first identifier assigning device in the present invention. The first laser engraving device 101 has a laser emitting unit (not shown) to form a desired first code 18. The first laser engraving device 101 forms a first code 18 having identification information on the electrode sheet 15. In addition, the method of assigning a QR code (registered trademark) to the electrode sheet 15 is not limited to laser-based engraving. The device for assigning the first code 18 can also print a QR code (registered trademark), for example.

[0150] <Coating device 102>

[0151] The coating device 102 is a device for coating the active material layer 17 on the current collector 16. The coating device 102 is an example of an active material layer forming device in the present invention. The coating device 102 applies the adjusted electrode composite material slurry to the current collector 16. In the case of manufacturing the positive electrode sheet 21 by the electrode manufacturing production line 1b, the current collector 16 is the positive electrode collector, and the active material layer 17 is the positive electrode active material layer. In the case of manufacturing the negative electrode sheet 22 by the electrode manufacturing production line 1b, the current collector 16 is the negative electrode collector, and the active material layer 17 is the negative electrode active material layer. In the coating of the electrode active material layer to the current collector, a known coating device can be used. As a coating device, for example, a slit coater, a gravure coater, a die coater, a comma coater, etc. can be used. The current collector 16 can be coated with the active material layer 17 on the side opposite to the side supported by the support roller in a state supported by the support roller. In addition, the active material layer 17 may also be applied to both sides of the collector 16. A drying device for drying the active material layer 17 applied to the collector 16 may be provided in the coating device. As the drying device, a device for drying the active material layer 17 by hot air, infrared rays, etc. may be used. In the present embodiment, the coating device 102 is configured to apply the electrode composite material slurry after reading the first code 18 by the sensor. In addition, the coating device 102 associates the identification information of the read first code 18 with the information of the coating conditions and sends it to the control device 200. The coating conditions are, for example, the coating amount of the electrode composite material slurry.

[0152] <First Inspection Device 105>

[0153] The first inspection device 105 is a device for measuring the width and in-line film thickness of the active material layer 17 applied to the collector 16 at a position upstream of the compression device 106. In the present embodiment, the first inspection device 105 is configured to perform the measurement after reading the first code 18 by the sensor. The first inspection device 105 measures the width and film thickness of the portion where the active material layer 17 is formed in the collector 16. However, the first inspection device 105 is not particularly limited as long as it can inspect the active material layer 17. In the present embodiment, as the first inspection device 105, a device capable of measuring the width and film thickness in a non-contact manner is used. The first inspection device 105 is configured to inspect the same position as the position of the first code 18 in the length direction of the collector 16 in the active material layer 17. The first inspection device 105 may be capable of measuring one portion in the width direction of the electrode sheet 15, may be capable of measuring multiple portions, or may be capable of measuring the entire range in the width direction. The first inspection device 105 associates the identification information of the first code 18 with the inspection information and sends it to the control device 200.

[0154] <Compression device 106>

[0155] The compression device 106 is a device for compressing the electrode sheet 15 conveyed by the conveying device 150. The active material layer 17 of the electrode sheet 15 is compressed in the up and down direction by the compression device 106, and can be adjusted to the desired thickness and density. In addition, the compression device 106 is configured to read the first code 18 using a sensor arranged near the unwinding roller 104 and the conveying amount of the electrode sheet 15. When the conveying distance of the first code 18 read by the sensor near the unwinding roller 104 reaches a predetermined specified distance, the compression device 106 recognizes that the first code 18 has reached the compression device 106. At this time, the compression device 106 obtains the identification information of the first code 18 from the sensor. The compression device 106 may also be provided with an encoder for measuring the conveying distance of the electrode sheet 15, for example. The compression device 106 has a pair of rolling rollers 106a and 106b. The electrode sheet 15 is clamped by a pair of rolling rollers 106a and 106b. The active material layer 17 is compressed by rolling through the gap between a pair of rolling rollers 106a and 106b. The pair of rolling rollers 106a and 106b are respectively connected to a stamping cylinder (not shown) that can be raised and lowered. By raising and lowering the stamping cylinder, the gap between the pair of rolling rollers 106a and 106b is changed. The length of the gap between the pair of rolling rollers 106a and 106b, the line pressure applied to the electrode sheet 15 by the pair of rolling rollers 106a and 106b, and the speed of the electrode sheet 15 when passing through the pair of rolling rollers 106a and 106b, that is, the rotation speed of the pair of rolling rollers 106a and 106b are controlled by the control device 200. The compression device 106 associates the identification information of the read first code 18 with the information of the above-mentioned control conditions and sends it to the control device 200.

[0156] <Second Inspection Device 107>

[0157] The second inspection device 107 is the same as the first inspection device 105 except that it is arranged downstream of the compression device 106. Here, a detailed description is omitted. The information of the inspection result obtained by inspecting the active material layer 17 using the first inspection device 105 or the second inspection device 107 is referred to as inspection information. The first inspection device 105 and the second inspection device 107 are examples of the inspection devices in the present invention.

[0158] 〈Half-cutting device 108〉

[0159] The half-cut device 108 is a device that cuts the electrode sheet 15 conveyed by the conveying device 150 at the center of the width direction of the electrode sheet 15, and is also called a slitter. The half-cut device 108 sends the length from one end of the electrode sheet 15 to the center in the width direction, i.e., the slit width, to the control device 200. The electrode sheet 15 to be half-cut and the electrode sheet 15 to be half-cut pass through the cutting device 109 and are respectively wound up on different winding rollers 111.

[0160] <Cutting device 109>

[0161] The cutting device 109 is a device for performing tab cutting of the electrode sheet 15 from the front end side in the length direction of the electrode sheet 15. The cutting device 109 is an example of a tab cutting device in the present invention. In the present embodiment, the cutting device 109 performs cutting by laser. The cutting device 109 is configured to perform tab cutting after reading the first code 18. In addition, the method by which the cutting device 109 reads the first code 18 is the same as that of the compression device 106. The cutting device 109 sends the conditions for performing tab cutting together with the identification information of the first code 18 to the control device 200. The conditions for performing tab cutting refer to, for example, the degree of laser output, etc. By passing through the cutting device 109, a positive electrode sheet 21 or a negative electrode sheet 22 is generated.

[0162] <Second Laser Marking Device 110>

[0163] The second laser marking device 110 is a device for forming the second code 19 on the electrode sheet 15 after the tab cutting. The second laser marking device 110 is an example of a second identifier assigning device. The method of assigning the second code 19 by the second laser marking device 110 is the same as that of the first laser marking device 101, so the description is omitted here.

[0164] <Control device 200>

[0165] The control device 200 may be, for example, a microcomputer. The control device 200 may include, for example, a communication interface, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The control device 200 is connected to each device of the manufacturing device 1 of the electrical storage device, and is configured to be connected to the first laser marking device 101, the coating device 102, the first inspection device 105, the compression device 106, the second inspection device 107, the half-cutting device 108, the cutting device 109, the second laser marking device 110, and the conveying device 150, and can be controlled separately.

[0166] The control device 200 has a recording device 210. The recording device 210 is a device that records the identification information of the first code 18 in association with the inspection information. In addition, the identification information of the second code 19 and the position assigned to the second code 19 in the collector 16 are stored in association in the recording device 210. The recording device 210 is, for example, a device that records information such as a hard disk drive. The recording device 210 records the information sent from each device connected to the control device 200 and associated with the identification information of the first code 18 for each identification information, and constructs a database. Figure 6 2 is a diagram showing an example of the database DT constructed by the recording device 210. In addition, the structure of the recording device 210 is not particularly limited. The recording device 210 may also be an external server device such as a cloud server.

[0167] The electrical storage device manufacturing apparatus 1 of the electrode sheet 15 has been described above. Next, a method for manufacturing the lithium ion secondary battery 10 will be described. Figure 7 1 is a flowchart showing a method for manufacturing a lithium-ion secondary battery 10. The method for manufacturing a lithium-ion secondary battery 10 disclosed herein includes a first identifier assigning step S1, a coating step S2, a first inspection step S3, a compression step S4, a second inspection step S5, a half-cutting step S6, a tab cutting step S7, a second identifier assigning step S8, a winding step S9, and an assembling step S10.

[0168] In the first identifier assigning step S1, the first code 18 is assigned to the electrode sheet 15 unwound from the unwinding roll 100. The first code 18 is formed by the first laser marking device 101. When the first laser marking device 101 forms the first code 18, it assigns identification information to the first code 18. At this time, the control device 200 records the identification information in the database DT possessed by the recording device 210.

[0169] exist Figure 7 In the coating step S2 shown, the active material layer 17 is formed on the current collector 16 by the coating device 102. The coating device 102 reads the first code 18 to determine its position while coating the electrode composite material slurry. The coating conditions at this time are controlled by the control device 200. The coating device 102 associates the identification information of the first code 18 with the coating conditions at the position and sends it to the control device 200. The control device 200 communicates with the data recorded in the database DT (refer to Figure 6 ) is associated with the identification information of the first code 18 in the coating condition.

[0170] After the coating step S2, the electrode sheet 15 is wound up on the winding roll 103 and moved to the unwinding roll 104. The method of moving the electrode sheet 15 wound up on the winding roll 103 is not particularly limited, and for example, the electrode sheet 15 is conveyed to the unwinding roll 104 by an operator. The conveyed electrode sheet 15 is unwinded from the unwinding roll 104.

[0171] In the first inspection step S3, inspection information obtained by inspecting the state of the active material layer 17 while specifying the position of the strip-shaped current collector 16 in association with the first code 18 is recorded. In this embodiment, the width and online film thickness of the active material layer 17 are measured by the first inspection device 105, and the width and online film thickness of the active material layer 17 at the position in the length direction to which the first code 18 is assigned are associated with the identification information of the first code 18 and sent to the control device 200. The control device 200 is configured to record the width and online film thickness of the active material layer 17 at the position in the length direction to which the first code 18 is assigned in association with the identification information of the first code 18 in the database DT.

[0172] In the compression step S4, the active material layer 17 is compressed by the compression device 106. The compression device 106 performs compression after reading the identification information of the first code 18 of the compressed part. After reading the first code 18 by the sensor provided near the unwinding roller 104, the compression device 106 identifies that the conveying amount of the electrode sheet 15 has reached a prescribed distance, and obtains the identification information of the first code 18 by the sensor. The compression device 106 performs compression while controlling the rolling rollers 106a and 106b under prescribed conditions. The compression device 106 associates the identification information of the read first code 18 with the compression conditions at the position and sends it to the control device 200. The compression device 106 sends the value of the line pressure to the control device 200, for example.

[0173] In the second inspection step S5, inspection information obtained by inspecting the state of the active material layer 17 while specifying the position of the strip-shaped current collector 16 in association with the first code 18 is recorded. In this embodiment, the width and online film thickness of the active material layer 17 are measured by the second inspection device 107, and the width and online film thickness of the active material layer 17 at the position in the length direction to which the first code 18 is assigned are associated with the identification information of the first code 18 and sent to the control device 200. The control device 200 is configured to record the width and online film thickness of the active material layer 17 at the position in the length direction to which the first code 18 is assigned in association with the identification information of the first code 18 in the database DT.

[0174] In the half-cutting step S6, the electrode sheet 15 is cut at the center in the width direction by the half-cutting device 108. At this time, the half-cutting device 108 sends the conditions of the slit width to the control device 200.

[0175] In the tab cutting process step S7, the tab cutting of the electrode sheet 15 is performed using the cutting device 109. The cutting device 109 reads the identification information of the first code 18 engraved in the tab forming area 16aa where the tab cutting is performed to determine its position while performing the tab cutting. That is, the tab cutting is performed while determining the position in the longitudinal direction of the electrode sheet 15. The method by which the cutting device 109 obtains the identification information of the first code 18 is the same as that in the compression process S4. The cutting device 109 associates the identification information of the read first code 18 with the cutting conditions and sends it to the control device 200. The cutting conditions refer to, for example, the degree of output of the laser during the tab cutting. In addition, by the tab cutting, the code engraving area 16ab is cut off and discarded.

[0176] In the second identifier assigning step S8, the second code 19 is assigned to the tab formed in the tab cutting processing step S7. When the formed sheet is a positive electrode sheet 21, the second code 19 is assigned to the tab 21t (see Figure 2 ). In the case where the formed sheet is a negative electrode sheet 22, the second code 19 is given to the electrode tab 22t (refer to Figure 2 ) part. The method of assigning the second code 19 is, for example, forming by laser in the same manner as the first code 18. In the database DT, identification information of the second code 19 and the position in the collector 16 are stored in association. For example, a number as identification information is stored in association with the distance from the front end of the collector 16 in the longitudinal direction to the second code 19.

[0177] In the winding step S9, Figure 3 As shown, the positive electrode sheet 21 and the negative electrode sheet 22 that have been subjected to the tab cutting process are overlapped and wound with the separator sheets 31 and 32 interposed therebetween. Thus, the electrode body 20 is manufactured. At this time, the winding device can read the second code 19 formed on the tab 21t of the positive electrode sheet 21 and the tab 22t of the negative electrode sheet 22. Thus, even after the winding step S9, the inspection information of the active material layer 17 along the length direction of the positive electrode sheet 21 and the negative electrode sheet 22 included in the electrode body 20 can be obtained afterwards through the second code 19.

[0178] exist Figure 7In the assembly process S10 shown, the electrode body 20 is accommodated and sealed in the battery case 41 by a known method. In addition, in the assembly process S10, it can be configured to read the inherent number assigned to the battery case 41. The read inherent number is sent to the control device 200. The control device 200 is configured to record the inherent number in the database DT in association with the second code 19 contained in the electrode body 20 accommodated in the battery case 41. The assembly device accommodates the electrode body 20 in the battery case 41 in association with the inherent number and the identification number of the second code 19. When the electrode body 20 is accommodated and sealed in the battery case 41, the injection of the electrolyte, the initial charge, and the aging treatment are performed. Here, in the injection of the electrolyte and the initial charge, the amount of electrolyte injection and the initial charging time are calculated by recording each information in the database DT in association with the identification information of the first code 18. For example, when the measured value of the film thickness is relatively large, the amount of electrolyte that the electrode body 20 can absorb becomes larger, so the amount of electrolyte injection is increased. In addition, for example, when the membrane density is relatively high, it is difficult for the electrode body 20 to absorb the electrolyte, so the amount of electrolyte injection is increased. In addition, the injection amount can be determined by the operator while observing the inspection information of the database DT, or it can be automatically calculated by the control device 200 using the inspection information of the database DT. The aging treatment can be performed by a known method.

[0179] In addition, the process of manufacturing the lithium-ion secondary battery 10 is not limited to the above order. For example, the electrode sheet 15 may be wound after the half-cutting process and before the tab cutting process. In this case, the tab cutting process and the second code 19 are performed while the half-cut electrode sheet 15 is rolled out, and the assembly process is directly performed.

[0180] The position where the second code 19 is given is not limited to the tabs 21t and 22t. The second code 19 may be added to the outer portion of the wound electrode body 20. Alternatively, the second code 19 may be given to the outer side when the lithium ion secondary battery 10 is assembled.

[0181] As described above, in the above-mentioned embodiment, the first codes 18 are formed at equal intervals in the non-formed region 16a along the longitudinal direction of the current collector 16. In the first inspection step S3 and the second inspection step S5, while the position in the longitudinal direction of the current collector 16 is determined using the first code 18, the inspection information of the active material layer 17 is recorded in the recording device 210. Thus, the inspection information of the active material layer 17 at each position of the current collector 16 is recorded in association with the identification information in the database DT of the recording device 210. The inspection information of the active material layer 17 corresponding to the position to which the first code 18 is added can be determined afterwards, and the individual difference of the electrode material used for the unit can be predicted or grasped afterwards.

[0182] In the above-mentioned embodiment, after obtaining the identification information of the first code 18 using the sensor provided near the unwinding roller 104 and the conveying amount of the electrode sheet 15, the tab cutting is performed. The second code 19 is added to the predetermined position of the tab 21t and the tab 22t formed by the tab cutting process. In this case, the information associated with the first code 18 can be obtained through the identification information of the second code 19. Therefore, the inspection information of the active material layer 17 along the length direction of the positive electrode sheet 21 and the negative electrode sheet 22 after the tab cutting can be obtained afterwards through the identification information of the second code 19.

[0183] In addition, the second code 19 can also be assigned before the tab is cut. Figure 8 is shown with Figure 7 The flowchart shown is a flowchart of a method for manufacturing a lithium-ion secondary battery 10 in a different order. Steps S1 to S6, step S9, and step S10 are respectively Figure 7 The flowchart shown is the same as Figure 8 As shown, the second identifier assignment step S8 may also be performed before the tab cutting process step S7. That is, after the second code 19 is added, the tabs 21t and 22t are formed by the tab cutting process. At this time, the first code 18 and the second code 19 may be read, matched with the positions of the positive electrode sheet 21 and the negative electrode sheet 22 along the length direction, and the first code 18 and the second code 19 may be associated and stored. In this case, after the tab cutting is performed, the inspection information of the active material layer 17 of the positive electrode sheet 21 and the negative electrode sheet 22 along the length direction after the tab cutting, which is associated with the first code 18, may be obtained through the identification information of the second code 19.

[0184] In the above-mentioned embodiment, there is further provided a winding step in which the positive electrode sheet 21 and the negative electrode sheet 22 that have been subjected to the tab cutting process are wound up while reading the second code 19. In this case, the inspection information of the active material layer 17 corresponding to the position to which the first code 18 is added in the long strip-shaped positive electrode sheet 21 and the negative electrode sheet 22 can be obtained from the electrode body 20 through the identification information of the second code 19. Therefore, the inspection information of the active material layer 17 along the length direction of the positive electrode sheet 21 and the negative electrode sheet 22 included in the electrode body 20 can be obtained afterwards.

[0185] In the above-mentioned embodiment, there are further provided: a step of housing the wound electrode body 20 in the battery case 41; a step of acquiring the unique number added to the battery case 41; and a step of recording the unique number in association with the second code 19 of the electrode body 20 housed in the battery case 41 in the recording device 210. In this case, the identification information of the second code 19 of the electrode body 20 housed in the battery case 41 can be acquired by the unique number of the battery case 41. Furthermore, the inspection information of the active material layer 17 corresponding to the position to which the first code 18 is added in the long strip-shaped positive electrode sheet 21 and the negative electrode sheet 22 can be acquired by the identification information of the second code 19. Therefore, after the electrode body 20 is housed in the battery case 41, the inspection information of the active material layer 17 along the longitudinal direction of the positive electrode sheet 21 and the negative electrode sheet 22 included in the electrode body 20 housed in the battery case 41 can be acquired by the unique number of the battery case 41.

[0186] In the above-mentioned embodiment, there is also a process of accommodating the wound electrode body 20 in the battery case 41; and a process of determining the amount of electrolyte injection and the initial charging time based on the information recorded in association with the identification information of the first code 18. For example, the required amount of electrolyte and the length of the optimal initial charging time will vary depending on the thickness of the film formed on the electrode body 20 during coating. By determining the amount of electrolyte and the length of the initial charging time based on the information recorded in association with the identification information of the first code 18, the quality of the manufactured lithium-ion secondary battery 10 can be maintained.

[0187] In the above-described embodiment, the identification information of the first code 18 and the inspection results by the first inspection device 105 and the second inspection device 107 are recorded in association in the database DT of the recording device 210. By reading the first code 18, the position in the collector 16 can be determined for the positive electrode collector 21a and the negative electrode collector 22a used for the electrode body 20, and the inspection information of the active material layer 17 at the position can be obtained.

[0188] In the above-mentioned embodiment, the second code 19 is formed on the tab 21t and the tab 22t. The second code 19 has identification information. The identification information of the second code 19 is recorded in the database DT possessed by the recording device 210. By reading the second code 19 when the electrode body 20 is formed, the position of the active material layer 17 included in the electrode body 20 in the collector 16 can be compared. By comparing the position of the active material layer 17 included in the electrode body 20, the inspection information of the active material layer 17 at the position can be obtained.

[0189] In the above-mentioned embodiment, in the database DT possessed by the recording device 210, the identification information possessed by the second code 19 and the inspection information of the active material layer 17 at the position are recorded in association. In addition, the tabs 21t and 22t forming the second code 19 are different from the code engraving area 16ab and are a part of the electrode body 20. Therefore, by reading the second code 19 contained in the electrode body 20, the position of the positive electrode collector 21a and the negative electrode collector 22a used for the electrode body 20 in the collector 16 can be determined, and the inspection information of the active material layer 17 at the position can be obtained. For example, the injection amount of the electrolyte solution injected into the lithium ion secondary battery 10 and the initial charging time can be estimated using the inspection information.

[0190] In the above embodiment, the identification number of the second code 19 and the unique number of the battery case 41 are recorded in association in the database DT of the recording device 210. Therefore, by reading the unique number of the battery case 41, the electrode body 20 housed in the battery case 41 can be identified.

[0191] In the above-mentioned embodiment, the identification number of the second code 19, the position of the current collector, and the inspection information of the active material layer 17 at the position are stored in association in the database DT of the recording device 210. Therefore, by reading the inherent number of the battery case 41, the identification number associated with the inherent number can be determined, and the position of the strip-shaped current collector 16 and the inspection information of the active material layer 17 at the position can be further determined based on the determined identification number.

[0192] In the above-mentioned embodiment, an inherent number is added to the battery case 41, but it is not limited to this. The inherent number can also be added to the sealing plate 41b. In this case, as in the above-mentioned embodiment, the inherent number is recorded in the recording device 210 in association with the second code 19. Therefore, the identification information of the second code 19 of the electrode body 20 can be obtained by the inherent number of the sealing plate 41b. Moreover, the inspection information of the active material layer 17 corresponding to the position to which the first code 18 is attached in the long strip-shaped positive electrode sheet 21 and the negative electrode sheet 22 can be obtained by the identification information of the second code 19. Therefore, after the electrode body 20 is accommodated in the battery case 41, the inspection information of the active material layer 17 along the length direction of the positive electrode sheet 21 and the negative electrode sheet 22 contained in the electrode body 20 accommodated in the battery case 41 can be obtained by the inherent number of the sealing plate 41b.

[0193] The inspection information included in the database DT is not limited to the above information. The information included in the database DT may include, for example, specific gravity of the electrode composite material slurry, width during coating, etc. In addition, the database DT may also include the batch number of the current collector 16 used.

[0194] In the above-mentioned embodiment, the first code 18 and the second code 19 are formed on the electrode sheet 15 , but the present invention is not limited thereto. Only one of the first code 18 and the second code 19 may be formed on the electrode sheet 15 .

[0195] In addition, Figure 5 In the embodiment shown, the manufacturing apparatus 1 of the electrical storage device is provided with the first inspection device 105 and the second inspection device 107 before and after (upstream and downstream) the compression device 106, respectively, but the present invention is not limited to this embodiment. For example, the inspection device may inspect the compressed active material layer 17 using the compression device 106. That is, the manufacturing apparatus 1 of the electrical storage device may include the second inspection device 107 instead of the first inspection device 105.

[0196] The invention disclosed herein has been described in various ways. Unless otherwise specified, the embodiments listed herein do not limit the present invention. In addition, the embodiments of the invention disclosed herein can be modified in various ways, and each component, each process mentioned herein can be appropriately omitted, or can be appropriately combined, unless any particular problem is caused.

[0197] In the above-mentioned embodiment, the identification information of the first code 18 is obtained by using a sensor provided near the unwinding roller 104 and the conveying amount of the electrode sheet 15. However, the cutting device 109 may also be provided with a sensor for reading the first code 18. The electrode sheet 15 is conveyed while the tab cutting is performed. Here, the electrode sheet 15 may sometimes break during the tab cutting. At this time, the path line is set while the electrode sheet 15 is conveyed at a relatively low speed. In order to grasp the position of the electrode sheet 15 when the path line is set, the first code 18 may also be read using a sensor provided by the cutting device 109.

[0198] As described above, the disclosure described in the following items is included in this specification.

[0199] Item 1:

[0200] A method for manufacturing an electric storage device, comprising: adding a first identifier for identifying a position in a strip-shaped current collector to a pre-set unformed region along a longitudinal direction of the strip-shaped current collector at a pre-determined interval;

[0201] forming an active material layer on a portion of the strip-shaped current collector excluding the unformed region; and

[0202] and an inspection step of recording inspection information obtained by inspecting a state of the active material layer while identifying a position of the strip-shaped current collector in association with the first identifier.

[0203] Item 2:

[0204] The method for manufacturing an electric storage device according to item 1, comprising:

[0205] a tab cutting process step of cutting the tab in the unformed region while reading the first identifier of the strip-shaped current collector to identify the position of the strip-shaped current collector; and

[0206] A step of adding a second identifier to a predetermined position of the tab formed by the tab cutting step.

[0207] Item 3:

[0208] The method for manufacturing an electric storage device according to item 1, comprising:

[0209] a second identifier assigning step of assigning a second identifier to a region of the non-formed region where a tab is formed by tab cutting; and

[0210] A tab cutting process step is performed in which the tab cutting is performed in the non-formed region to which the second identifier is assigned.

[0211] Item 4:

[0212] The method for manufacturing an electrical storage device according to item 2 or 3, further comprising a winding step of reading the second identifier and winding up the strip-shaped current collector subjected to the tab cutting process.

[0213] Item 5:

[0214] The method for manufacturing an electric storage device according to item 4, comprising:

[0215] a step of housing the electrode assembly in a battery case while reading the second identifier of the electrode assembly obtained in the winding step;

[0216] A step of obtaining a unique number added to the battery case; and

[0217] The step of recording the unique number of the battery case and the second identifier of the electrode assembly accommodated in the battery case in association with each other.

[0218] Item 6:

[0219] The method for manufacturing an electric storage device according to item 4, comprising:

[0220] a step of housing the electrode assembly in a battery case having an opening while reading the second identifier of the electrode assembly obtained in the winding step;

[0221] The step of sealing the opening with a sealing plate having a unique number attached thereto;

[0222] A step of obtaining a unique number added to the sealing plate; and

[0223] A step of recording the unique number of the sealing plate and the second identifier of the electrode assembly accommodated in the sealing plate in association with each other.

[0224] Item 7:

[0225] The method for manufacturing an electric storage device according to item 4, comprising:

[0226] a step of housing the electrode assembly in a battery case while reading the second identifier of the electrode assembly obtained in the winding step; and

[0227] A step of determining an injection amount of an electrolyte solution and an initial charging time based on the information recorded in association with the first identifier.

[0228] Item 8:

[0229] A recording device, which is configured to record a first identifier in association with inspection information of an active material layer, wherein the first identifier is attached to a pre-set unformed area along the length direction of a strip-shaped current collector at predetermined intervals and is used to determine the position in the strip-shaped current collector, and the inspection information is obtained by inspecting the active material layer formed on the strip-shaped current collector while determining the position of the strip-shaped current collector in association with the first identifier.

[0230] Item 9:

[0231] According to the recording device described in Item 8, the recording device is configured to further record a second identifier in association with the position of the strip-shaped current collector to which the second identifier is attached, and the second identifier is attached to a predetermined position of the pole ear formed in the unformed area of ​​the strip-shaped current collector.

[0232] Item 10:

[0233] The recording device according to item 9 is configured to be capable of acquiring inspection information of the strip-shaped current collector and the active material layer at a position along the length direction of the current collector based on the second identifier.

[0234] Item 11:

[0235] According to the recording device described in Item 8, the recording device is configured to further record a second identifier in association with the inherent number of the battery case, wherein the second identifier is assigned to the electrode tab of the electrode body made of the strip-shaped collector, and the inherent number of the battery case is assigned to the battery case that accommodates the electrode body.

[0236] Item 12:

[0237] The recording device according to item 11 is configured to acquire the position of the strip-shaped current collector for the electrode assembly housed in the battery case and the inspection information of the active material layer at the position based on the unique number of the battery case.

[0238] Item 13:

[0239] A manufacturing device for an electric storage device, comprising:

[0240] a first identifier assigning device for assigning a first identifier for specifying a position in the strip-shaped current collector to a pre-set unformed region along a longitudinal direction of the strip-shaped current collector at a pre-determined interval;

[0241] an active material layer forming device for forming an active material layer on a portion of the strip-shaped current collector excluding the unformed region;

[0242] an inspection device that inspects a state of the active material layer while identifying a position of the strip-shaped current collector in association with the first identifier; and

[0243] A recording device is used to record the inspection information detected by the inspection device.

[0244] Item 14:

[0245] The manufacturing apparatus of the electrical storage device according to item 13, further comprising:

[0246] a tab cutting device for cutting the tab in the unformed region while reading the first identifier of the strip-shaped current collector to identify the position of the strip-shaped current collector; and

[0247] A second identifier assigning device is configured to assign a second identifier to a predetermined position of the tab formed by the tab cutting device.

[0248] Item 15:

[0249] The manufacturing apparatus of the electrical storage device according to item 13, further comprising:

[0250] a second identifier assigning device that assigns a second identifier to a region of the non-formed region where a tab is formed by tab cutting; and

[0251] A tab cutting device is provided for cutting the tab in the non-formed region to which the second identifier is assigned by the second identifier assigning device.

[0252] Item 16:

[0253] The manufacturing apparatus of the electrical storage device according to item 14 or 15, further comprising a winding device that reads the second identifier and winds up the strip-shaped current collector from which the tab has been cut.

[0254] Item 17:

[0255] The manufacturing apparatus of the electrical storage device according to item 16 further comprises an assembling apparatus that associates the second identifier of the electrode body produced by the winding apparatus with a unique number given to a battery case that houses the electrode body, and houses the electrode body in the battery case.

[0256] Item 18:

[0257] The manufacturing apparatus of the electrical storage device according to item 16, further comprising:

[0258] an assembling device that reads the second identifier of the electrode body produced by the winding device, accommodates the electrode body in a battery case having an opening, and seals the opening with a sealing plate to which a unique number is added; and

[0259] A recording device records the unique number of the sealing plate and the second identifier of the electrode assembly accommodated in the sealing plate in association with each other.

[0260] Item 19:

[0261] The manufacturing apparatus of the electrical storage device according to item 16, further comprising:

[0262] an assembling device that accommodates the electrode assembly in a battery case while reading the second identifier of the electrode assembly produced by the winding device; and

[0263] A control device determines an injection amount of an electrolyte solution and an initial charging time based on information recorded in association with the first identifier.

Claims

1. A method for manufacturing an electric storage device, wherein: The method for manufacturing the power storage device comprises: A step of adding a first identifier for identifying a position in the strip-shaped current collector to a pre-set unformed region along a longitudinal direction of the strip-shaped current collector at a pre-determined interval; forming an active material layer on a portion of the strip-shaped current collector excluding the unformed region; and and an inspection step of recording inspection information obtained by inspecting a state of the active material layer while identifying a position of the strip-shaped current collector in association with the first identifier.

2. The method for manufacturing an electric storage device according to claim 1, wherein: The method for manufacturing the power storage device comprises: a tab cutting process step of cutting the tab in the unformed region while reading the first identifier of the strip-shaped current collector to identify the position of the strip-shaped current collector; and A step of adding a second identifier to a predetermined position of the tab formed by the tab cutting step.

3. The method for manufacturing an electric storage device according to claim 1, wherein: The method for manufacturing the power storage device comprises: a second identifier assigning step of assigning a second identifier to a region of the non-formed region where a tab is formed by tab cutting; and A tab cutting process step is performed in which the tab cutting is performed in the non-formed region to which the second identifier is assigned.

4. The method for manufacturing an electrical storage device according to claim 2 or 3, wherein: The method for manufacturing an electrical storage device further includes a winding step of reading the second identifier and winding the strip-shaped current collector from which the tab has been cut.

5. The method for manufacturing an electric storage device according to claim 4, wherein: The method for manufacturing the power storage device comprises: a step of housing the electrode assembly in a battery case while reading the second identifier of the electrode assembly obtained in the winding step; A step of obtaining a unique number added to the battery case; and The step of recording the unique number of the battery case and the second identifier of the electrode assembly accommodated in the battery case in association with each other.

6. The method for manufacturing an electric storage device according to claim 4, wherein: The method for manufacturing the power storage device comprises: a step of housing the electrode assembly in a battery case having an opening while reading the second identifier of the electrode assembly obtained in the winding step; The step of sealing the opening with a sealing plate having a unique number attached thereto; A step of obtaining a unique number added to the sealing plate; and A step of recording the unique number of the sealing plate and the second identifier of the electrode assembly accommodated in the sealing plate in association with each other.

7. The method for manufacturing an electric storage device according to claim 4, wherein: The method for manufacturing the power storage device comprises: a step of housing the electrode assembly in a battery case while reading the second identifier of the electrode assembly obtained in the winding step; and A step of determining an injection amount of an electrolyte solution and an initial charging time based on the information recorded in association with the first identifier.

8. A recording device, wherein: The recording device is configured to record a first identifier in association with inspection information of an active material layer, wherein the first identifier is attached to a pre-set unformed area along a length direction of a strip-shaped current collector at predetermined intervals and is used to determine a position in the strip-shaped current collector, and the inspection information is obtained by inspecting the active material layer formed on the strip-shaped current collector while determining the position of the strip-shaped current collector in association with the first identifier.

9. The recording device according to claim 8, wherein: The recording device is configured to further record a second identifier in association with a position of the strip-shaped current collector to which the second identifier is added, the second identifier being added to a predetermined position of the tab formed in the non-formed region of the strip-shaped current collector.

10. The recording device according to claim 9, wherein: The recording device is configured to be able to acquire inspection information of the strip-shaped current collector and the active material layer at a position along the length direction of the current collector based on the second identifier.

11. The recording device according to claim 8, wherein The recording device is configured to further record a second identifier assigned to a tab of an electrode body made of the strip-shaped current collector in association with a unique number of a battery case that is assigned to the battery case housing the electrode body.

12. The recording device according to claim 11, wherein The recording device is configured to acquire the position of the strip-shaped current collector of the electrode assembly housed in the battery case and the inspection information of the active material layer at the position based on the unique number of the battery case.

13. A manufacturing apparatus for an electrical storage device, wherein: The manufacturing apparatus of the electric storage device comprises: a first identifier assigning device for assigning a first identifier for specifying a position in the strip-shaped current collector to a pre-set unformed region along a longitudinal direction of the strip-shaped current collector at a pre-determined interval; an active material layer forming device for forming an active material layer on a portion of the strip-shaped current collector excluding the unformed region; an inspection device that inspects a state of the active material layer while identifying a position of the strip-shaped current collector in association with the first identifier; as well as A recording device is used to record the inspection information detected by the inspection device.

14. The manufacturing apparatus of the electrical storage device according to claim 13, wherein: The manufacturing apparatus for the electrical storage device further comprises: a tab cutting device for cutting the tab in the unformed region while reading the first identifier of the strip-shaped current collector to determine the position of the strip-shaped current collector; as well as A second identifier assigning device is configured to assign a second identifier to a predetermined position of the tab formed by the tab cutting device.

15. The manufacturing apparatus of the electrical storage device according to claim 13, wherein: The manufacturing apparatus for the electrical storage device further comprises: a second identifier assigning device that assigns a second identifier to a region of the non-formed region where a tab is formed by tab cutting; and A tab cutting device is provided for cutting the tab in the non-formed region to which the second identifier is assigned by the second identifier assigning device.

16. The manufacturing apparatus for an electrical storage device according to claim 14 or 15, wherein: The electrical storage device manufacturing apparatus further includes a winding device that reads the second identifier and winds up the strip-shaped current collector from which the tab has been cut.

17. The manufacturing apparatus of the electrical storage device according to claim 16, wherein: The electrical storage device manufacturing apparatus further includes an assembling device that associates the second identifier of the electrode assembly produced by the winding device with a unique number given to a battery case housing the electrode assembly and houses the electrode assembly in the battery case.

18. The manufacturing apparatus of the electrical storage device according to claim 16, wherein: The manufacturing apparatus for the electrical storage device further comprises: an assembling device that reads the second identifier of the electrode body produced by the winding device, accommodates the electrode body in a battery case having an opening, and seals the opening with a sealing plate to which a unique number is added; as well as A recording device records the unique number of the sealing plate and the second identifier of the electrode assembly accommodated in the sealing plate in association with each other.

19. The manufacturing apparatus of the electrical storage device according to claim 16, wherein: The manufacturing apparatus for the electrical storage device further comprises: an assembling device that accommodates the electrode body in a battery case while reading the second identifier of the electrode body produced by the winding device; as well as A control device determines an injection amount of an electrolyte solution and an initial charging time based on information recorded in association with the first identifier.

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