Power storage device and method for manufacturing the same

Abstract

The present application relates to an electric power storage device and a manufacturing method thereof, the manufacturing method of the electric power storage device including: an electrode body manufacturing step of manufacturing an electrode body having a first tab and a second tab; a housing step of housing the first tab and the second tab in a tab housing space using a separator having a communication space connecting the tab housing space and a space outside the separator, after the electrode body manufacturing step; and a bending step of bending the first tab and the second tab so that a first guide portion faces a main outer surface of the first tab and a second guide portion faces a main outer surface of the second tab, after the housing step.

Description

Technical Field

[0001] This technology relates to energy storage devices and their manufacturing methods. Background Technology

[0002] Japanese Patent No. 4537353 discloses a square energy storage device in which a positive terminal is provided on one side of the battery casing of a secondary battery and a negative terminal is provided at the other end.

[0003] For example, a low-profile rechargeable battery can be obtained by making the energy storage device square, with a positive terminal on one side of the battery casing and a negative terminal at the other end. However, there is room for further improvement in order to make a rechargeable battery that can be manufactured efficiently and stably. For example, a separator can be provided inside the battery casing between the electrode body and the sealing plate.

[0004] When connecting the tab electrodes (tab electrode assembly) provided on the electrode body to the electrode terminals of the sealing plate, it is necessary to pass the tab electrodes through the opening provided in the separator, but this requires work space, and the process needs to be improved. This issue is not limited to secondary batteries, but also applies to rechargeable energy storage devices. Summary of the Invention

[0005] This technology was developed to address the aforementioned issues, and its purpose is to provide an energy storage device and its manufacturing method that can be manufactured efficiently and stably by further improving the manufacturing process of the energy storage device.

[0006] This technology provides a method for manufacturing the following energy storage device.

[0007] [1] A method for manufacturing an energy storage device, the energy storage device comprising: an electrode body including a first electrode and a second electrode with a polarity different from the first electrode; and a housing for housing the electrode body, the housing comprising a housing body having a first opening at one end and a first sealing plate sealing the first opening, the electrode body having a first tab and a second tab electrically connected to the first electrode at the end on the side of the first sealing plate, the first tab and the second tab being disposed between the first sealing plate and the electrode body, the first tab and the second tab being disposed in a bent state within a tab housing space disposed in the first sealing plate, the first sealing plate including a first guide portion and a second guide portion being disposed opposite to each other, the tab housing space being disposed between the first guide portion and the second guide portion. Between the second guide portions, the main outer surface of the first electrode ear faces the first guide portion, and the main outer surface of the second electrode ear faces the second guide portion. The method for manufacturing the energy storage device comprises: an electrode body manufacturing step, manufacturing an electrode body having the first electrode ear and the second electrode ear; a storage step, after the electrode body manufacturing step, using the first separator having a connecting space connecting the electrode ear storage space to the space outside the first separator to store the first electrode ear and the second electrode ear in the electrode ear storage space via the connecting space; and a bending step, after the storage step, bending the first electrode ear and the second electrode ear in a state where the main outer surface of the first electrode ear faces the first guide portion and the main outer surface of the second electrode ear faces the second guide portion.

[0008] [2] The method for manufacturing an energy storage device according to [1] is characterized by having a step of joining at least one of the first electrode and the second electrode to the current collector before the above-mentioned storage step.

[0009] [3] The method of manufacturing the energy storage device according to [1] or [2] is characterized in that the first electrode has a first recess that is recessed toward the second electrode in a bent state, the second electrode has a second recess that is recessed toward the first electrode in a bent state, the first guide has a first protrusion, the second guide has a second protrusion, the first protrusion is disposed within the first recess, and the second protrusion is disposed within the second recess.

[0010] [4] The method for manufacturing an energy storage device according to [3] is characterized in that the first guide portion has a first concave curved surface on the first sealing plate side of the first protrusion, and the second guide portion has a second concave curved surface on the first sealing plate side of the second protrusion.

[0011] [5] A method for manufacturing an energy storage device according to any one of [1]-[4], characterized in that it includes an insertion step after the above-mentioned storage step, in which the electrode body and the first separator are inserted into the housing body, and after the above-mentioned insertion step, in the above-mentioned bending step, the first electrode and the second electrode are bent while the first guide portion abuts against the first tab and the second tab abuts against the second guide portion.

[0012] [6] The method of manufacturing an energy storage device according to any one of [1]-[5] is characterized in that the housing body has a second opening at the other end, and the second opening is sealed by a second sealing plate.

[0013] [7] A method for manufacturing an energy storage device according to any one of [1]-[6], characterized in that the first insulating material is disposed at one end of the electrode body, and the electrode body and the first insulating material are covered by an insulating sheet.

[0014] [8] The method for manufacturing an energy storage device according to [7] is characterized by comprising: a first configuration step, wherein the first separator is disposed on the insulating sheet; a second configuration step, wherein after the first configuration step, the first electrode and the second electrode are disposed in the electrode storage space and the electrode body is disposed on the insulating sheet; and a covering step, wherein after the second configuration step, the electrode body and the first separator are covered with the insulating sheet.

[0015] [9] The method of manufacturing an energy storage device according to any one of [1]-[8] is characterized in that, in the region defined by the first guide portion and the second guide portion, the opposing regions of the first guide portion and the second guide portion are mutually convex curved shapes or chamfered shapes.

[0016]

[10] The method for manufacturing an energy storage device according to any one of [1]-[9] is characterized in that, in the above-mentioned storage process, the first electrode and the second electrode are stored in the electrode storage space while the first separator is deformed in such a way that the width of the above-mentioned connecting space is increased, and then the first separator is deformed in such a way that the width of the above-mentioned connecting space is decreased.

[0017] This technology provides the following energy storage devices.

[0018]

[11] An energy storage device, characterized in that the energy storage device comprises: an electrode body including a first electrode and a second electrode with a polarity different from that of the first electrode; and a housing for housing the electrode body, the housing comprising a housing body having a first opening at one end and a first sealing plate sealing the first opening, the electrode body having a first tab and a second tab electrically connected to the first electrode at one end of the electrode body on the side of the first sealing plate, the first tab and the second tab being electrically connected to the first electrode in a bent state, and a first separator being disposed between the first sealing plate and the electrode body. The first separator includes a main body and a first guide and a second guide arranged in a manner connected to and opposite to the main body. The first guide and the second guide define a tab storage space and a connecting space connecting the tab storage space to an external space. The connecting space is defined on the opposite side of the main body through the first guide and the second guide. The first tab is bent when the first guide and the main outer surface of the first tab are facing each other, and the second tab is bent when the second guide and the main outer surface of the second tab are facing each other.

[0019]

[12] According to the energy storage device of

[11] , the first electrode has a first recess that is recessed toward the second electrode in a bent state, the second electrode has a second recess that is recessed toward the first electrode in a bent state, the first guide has a first protrusion, the second guide has a second protrusion, the first protrusion is disposed within the first recess, and the second protrusion is disposed within the second recess.

[0020]

[13] The energy storage device according to

[12] is characterized in that the first guide portion has a first concave curved surface on the first sealing plate side of the first protrusion, and the second guide portion has a second concave curved surface on the first sealing plate side of the second protrusion.

[0021] The above and other objects, features, aspects and advantages of the invention will become clear from the following detailed description relating to the invention as understood in conjunction with the accompanying drawings. Attached Figure Description

[0022] Figure 1 This is a front view showing the configuration of the secondary battery in Embodiment 1.

[0023] Figure 2 This indicates viewing from the direction of arrow II. Figure 1 The diagram shows the state of the secondary battery.

[0024] Figure 3 This indicates viewing from the direction of arrow III. Figure 1 The diagram shows the state of the secondary battery.

[0025] Figure 4 This indicates viewing from the direction of arrow IV. Figure 1 The diagram shows the state of the secondary battery.

[0026] Figure 5 This indicates viewing from the direction of arrow V. Figure 1 The diagram shows the state of the secondary battery.

[0027] Figure 6 yes Figure 1 The diagram shows a front sectional view of a secondary battery.

[0028] Figure 7 This is a cross-sectional view of the negative electrode plate.

[0029] Figure 8 This is the front view of the negative electrode plate.

[0030] Figure 9 This is a cross-sectional view of the positive electrode plate.

[0031] Figure 10 This is the front view of the positive electrode plate.

[0032] Figure 11 yes Figure 1 The XI-XI cross-sectional view of the secondary battery shown.

[0033] Figure 12 yes Figure 1 The XII-XII cross-sectional view of the secondary battery is shown.

[0034] Figure 13 This is the first three-dimensional diagram representing the shape of the isolated object.

[0035] Figure 14 This is the second three-dimensional diagram representing the shape of the isolated object.

[0036] Figure 15 yes Figure 13 The XV-XV end face view of the isolator is shown.

[0037] Figure 16 This is a flowchart illustrating the manufacturing method of the secondary battery according to Embodiment 1.

[0038] Figure 17 This is a perspective view showing the state in which the two electrode bodies of the secondary battery according to Embodiment 1 are connected to the current collector.

[0039] Figure 18 yes Figure 17 The XVIII-XVIII sectional view of the electrode body and the current collector shown.

[0040] Figure 19 It is a three-dimensional diagram showing the state in which an insulating material is installed on the electrode body.

[0041] Figure 20 This is the first schematic diagram showing the state before the electrode body is covered by an insulating sheet and the insulator.

[0042] Figure 21 This is the second schematic diagram showing the state before the electrode body is covered by an insulating sheet and the insulator.

[0043] Figure 22 It is a three-dimensional diagram showing the state after the electrode body and the insulator are covered by an insulating sheet.

[0044] Figure 23 It is a three-dimensional diagram showing the current collector on the positive side with a sealing plate installed.

[0045] Figure 24 It is a cross-sectional view showing the state before the negative electrode tab on the negative electrode side is bent.

[0046] Figure 25 It is a cross-sectional view showing the state after the negative electrode tab on the negative electrode side has been bent.

[0047] Figure 26 It is a three-dimensional diagram showing the structure of a secondary battery.

[0048] Figure 27 This is a diagram showing the structure of the separator in Embodiment 2.

[0049] Figure 28 Figure 1 shows the structure of the separator in Embodiment 3.

[0050] Figure 29 This is Figure 2, which shows the structure of the separator in Embodiment 3.

[0051] Figure 30 Figure 1 shows the structure of the separator in Embodiment 4.

[0052] Figure 31 This is Figure 2, which shows the structure of the separator in Embodiment 4. Detailed Implementation

[0053] The following describes the implementation of this technology. Sometimes, the same or equivalent parts are labeled with the same reference numerals in the accompanying drawings, and their descriptions will not be repeated.

[0054] In the embodiments described below, when numbers, quantities, etc., are mentioned, the scope of this technology is not necessarily limited to those numbers, quantities, etc., unless specifically stated otherwise. In the embodiments described below, each constituent element is not necessarily essential to this technology unless specifically stated otherwise. This technology is not necessarily limited to performing all the effects mentioned in this embodiment.

[0055] In this specification, the terms "comprise," "include," and "have" are open-ended. That is, when a certain component is included, other components besides that component may be included, or other components besides that component may not be included.

[0056] In this specification, when using geometric terms and terms indicating positional or directional relationships, such as "parallel," "orthogonal," "tilted at 45°," "coaxial," and "along," these terms are permissible with manufacturing errors or slight variations. In this specification, when using terms indicating relative positional relationships such as "upper side" and "lower side," these terms are used to indicate the relative positional relationship in a given state. Depending on the orientation of each mechanism (e.g., reversing the entire mechanism vertically), the relative positional relationship can be reversed or rotated to any angle.

[0057] In this specification, a secondary battery is described as an example of an "energy storage device," but it is not limited to secondary batteries. "Energy storage device" is a term used to refer to all energy storage devices that can be repeatedly charged and discharged, including secondary batteries (chemical batteries) such as lithium-ion secondary batteries and nickel-metal hydride batteries, and capacitors (physical batteries) such as lithium-ion capacitors and double-layer capacitors.

[0058] In this instruction manual, the positive and negative electrodes may be collectively referred to as "electrodes".

[0059] In this application specification, the first direction (X direction) is sometimes referred to as the "width direction" of the secondary battery, electrode body, and housing body; similarly, the second direction (Z direction) is referred to as the "height direction" of the secondary battery or housing body; and similarly, the third direction (Y direction) is referred to as the "thickness direction" of the secondary battery or housing body. For ease of understanding of this technology, some parts of the detailed shapes of the components in the drawings are omitted.

[0060] [Implementation Method 1]

[0061] (The overall structure of a secondary battery)

[0062] Reference Figures 1 to 6 The overall structure of the secondary battery 1 in Embodiment 1 will be described.

[0063] In this specification, "secondary battery" is not necessarily limited to a square shape; it may also include cells of other shapes such as cylindrical, pouch-shaped, and sheet-shaped. Furthermore, "secondary batteries" can be installed in hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs). However, the application of "secondary batteries" is not limited to vehicle use.

[0064] The secondary battery 1 includes a casing 100, an electrode body 200, an electrode terminal 300, and a current collector 400. The casing 100 includes a casing body 110, a sealing plate 120 (first sealing plate), and a sealing plate 130 (second sealing plate).

[0065] When constructing a battery pack including secondary batteries 1, multiple secondary batteries 1 are stacked along their thickness direction. The stacked secondary batteries 1 can be constrained along the stacking direction (Y direction) by a constraining member to become a battery module, or the battery pack can be directly supported on the side of the battery pack housing without using a constraining member.

[0066] The housing body 110 is composed of a cylindrical component, preferably a square cylindrical component. This results in a square secondary battery 1. The housing body 110 is made of metal. Specifically, the housing body 110 is made of aluminum, aluminum alloy, iron, or iron alloy, etc.

[0067] like Figure 1 as well as Figure 2 As shown, sealing plates 120 and 130 are respectively provided at both ends of the housing body. The housing body 110 can be constructed, for example, by having the end edges of bent plate-like components abut against each other. Figure 2 The illustrated joint 115 is joined together (e.g., by laser welding or other energy line irradiation) to form a square tube shape. The corners of the "square tube" may have rounded shapes. The secondary battery in this technology is not necessarily limited to a square secondary battery.

[0068] In this embodiment, the housing body 110 is formed to be longer in the width direction (X direction) than in the thickness direction (Y direction) and height direction (Z direction) of the secondary battery 1. The width of the housing body 110 in the X direction is preferably 30 cm or more. This allows for the construction of a relatively large (high-capacity) secondary battery 1. The height of the housing body 110 in the Z direction is preferably 20 cm or less, more preferably 15 cm or less, and even more preferably 10 cm or less. This allows for the construction of a relatively low-height secondary battery 1, for example, improving vehicle mountability.

[0069] The housing body 110 includes a pair of first side faces 111 and a pair of second side faces 112. The pair of first side faces 111 form part of the side faces of the housing 100. The pair of second side faces 112 form the bottom and top surfaces of the housing 100. The pair of first side faces 111 and the pair of second side faces 112 are arranged in a mutually intersecting manner. The pair of first side faces 111 and the pair of second side faces 112 are connected at their respective ends. Preferably, the area of ​​each of the pair of first side faces 111 is larger than the area of ​​each of the pair of second side faces 112.

[0070] like Figure 5 As shown, an exhaust valve 150 is provided on one of the pair of second side portions 112, on the second side portion 112A. The exhaust valve 150 extends along the width direction (X direction) of the secondary battery 1. The exhaust valve 150 extends along the X direction to a degree that it does not reach either end from the center of the housing body 110 in the X direction. The shape of the exhaust valve 150 can be appropriately modified.

[0071] The thickness of the plate-shaped component in the exhaust valve 150 is thinner than the thickness of the plate-shaped components other than the exhaust valve 150 in the housing body 110. As a result, when the pressure inside the housing 100 becomes above a predetermined value, the exhaust valve 150 breaks first than other parts in the housing body 110, venting the gas inside the housing 100 to the outside.

[0072] like Figure 2 As shown, a joining portion 115 is formed on the other of the pair of second side portions 112B. The joining portion 115 extends along the width direction (X direction) of the secondary battery 1. At the joining portion 115, the end edges of the plate-shaped members constituting the housing body 110 are joined together.

[0073] like Figure 3 As shown, an opening 113 (first opening) is provided at the end of the first side in the first direction (X direction) of the housing body 110. The opening 113 is sealed by a sealing plate 120. A joint portion 115 is formed in the opening 113 to seal the opening 113. The opening 113 and the sealing plate 120 have a generally rectangular shape with the short side in the Y direction and the long side in the Z direction. The generally rectangular shape includes a rectangular shape or a shape with rounded corners, etc., that is substantially rectangular.

[0074] A negative terminal 301 is provided on the sealing plate 120 (the first sealing plate). The position of the negative terminal 301 can be changed as appropriate.

[0075] like Figure 4As shown, an opening 114 (second opening) is provided at the end of the housing body 110 on the second side opposite to the first side in the first direction (X direction). That is, the opening 114 is located at the end opposite to the opening 113, and the opening 113 and the opening 114 are opposite to each other. The opening 114 is sealed by a sealing plate 130. A joint portion 115 is formed in the opening 114 to seal the opening 114. The opening 114 and the sealing plate 130 have a generally rectangular shape with the short side in the Y direction and the long side in the Z direction.

[0076] A positive terminal 302 and an injection hole 134 are provided on the sealing plate 130 (the second sealing plate). The injection hole 134 only needs to be large enough to inject electrolyte into the interior of the housing 100, and is preferably smaller than the insertion hole of the positive terminal 302 provided on the sealing plate 130. Preferably, the injection hole 134 is offset from the center of the sealing plate 130 in the Z direction. The positions of the positive terminal 302 and the injection hole 134 can be appropriately changed.

[0077] Sealing plates 120 and 130 are made of metal. Specifically, sealing plates 120 and 130 are made of aluminum, aluminum alloy, iron, or iron alloy.

[0078] The negative terminal 301 (first electrode terminal) is electrically connected to the negative terminal of the electrode body 200. The negative terminal 301 is mounted on the sealing plate 120, i.e., the housing 100.

[0079] The positive terminal 302 (second electrode terminal) is electrically connected to the positive electrode of the electrode body 200. The positive terminal 302 is mounted on the sealing plate 130, i.e., the housing 100.

[0080] The negative terminal 301 may be made of a conductive material (more specifically, a metal), such as copper or a copper alloy. Alternatively, a portion or layer made of aluminum or an aluminum alloy may be provided on the outer surface of the negative terminal 301.

[0081] The positive terminal 302 may be made of a conductive material (more specifically a metal), such as aluminum or an aluminum alloy.

[0082] The injection port 134 is sealed by a sealing component (not shown). Such sealing components can be, for example, blind rivets or other metal parts.

[0083] The electrode body 200 is a flat electrode body formed by stacking positive and negative electrode plates, as described later. Specifically, the electrode body 200 is a stacked electrode body in which multiple positive and multiple negative electrode plates are alternately stacked with a separator 800, as described later. However, in this specification, "electrode body" is not limited to a stacked electrode body, and may also be a wound electrode body formed by winding strip-shaped positive and negative electrode plates together with a strip-shaped separator. The separator may, for example, be made of a polyolefin-based microporous membrane. When the electrode body is a stacked electrode body including multiple positive and multiple negative electrode plates, positive electrode tabs disposed on each positive electrode plate can be stacked to form a positive electrode tab group, and negative electrode tabs disposed on each negative electrode plate can be stacked to form a negative electrode tab group.

[0084] like Figure 6 As shown, the housing 100 houses the electrode body 200. Figure 6 The first electrode 201, described later, is illustrated in the diagram. The first electrode 201 is housed within the housing 100 with its long side parallel to the X direction.

[0085] Specifically, one or more stacked electrode bodies are housed inside the insulating sheet 700 (described later) disposed within the housing 100, along with an electrolyte (not shown). As the electrolyte (non-aqueous electrolyte), for example, an electrolyte in which LiPF6 is dissolved at a concentration of 1.2 mol / L can be used, consisting of a non-aqueous solvent composed of ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC) mixed in a volume ratio (25°C) of 30:30:40. A solid electrolyte can also be used instead of the electrolyte.

[0086] The electrode body 200 includes a first electrode body 201. The first electrode body 201 includes a generally rectangular main body, a negative electrode tab group 220, and a positive electrode tab group 250.

[0087] The main body is composed of a negative electrode plate 210 and a positive electrode plate 240, described later. The negative electrode tab assembly 220 is located at the end of the main body on the first side of the first electrode body 201 in the first direction (X direction). In this embodiment, the first side is the sealing plate 120 side. The positive electrode tab assembly 250 is located at the end of the main body on the second side of the first electrode body 201 in the first direction (X direction). In this embodiment, the second side is the sealing plate 130 side.

[0088] The negative electrode tab group 220 and the positive electrode tab group 250 are formed in such a way that they protrude from the central portion of the electrode body 200 toward the sealing plate 120 or the sealing plate 130, respectively.

[0089] The current collector 400 includes a negative current collector 400A and a positive current collector 400B. The negative current collector 400A and the positive current collector 400B are each composed of plate-shaped components. The electrode body 200 is electrically connected to the negative terminal 301 and the positive terminal 302 via the current collector 400.

[0090] The negative current collector 400A is disposed on the sealing plate 120 via a resin insulating component. The negative current collector 400A is electrically connected to the negative electrode tab assembly 220 and the negative terminal 301. The negative current collector 400A may be made of a conductive material (more specifically, a metal), such as copper or a copper alloy. Details regarding the negative current collector 400A will be described later.

[0091] The positive current collector 400B is disposed on the sealing plate 130 via a resin insulating component. The positive current collector 400B is electrically connected to the positive electrode tab assembly 250 and the positive terminal 302. The positive current collector 400B may be made of a conductive material (more specifically, a metal), such as aluminum or an aluminum alloy. Alternatively, the positive electrode tab assembly 250 may be electrically connected to the sealing plate 130 directly or via the positive current collector 400B. In this case, the sealing plate 130 can function as the positive terminal 302. Details regarding the positive current collector 400B will be described later.

[0092] (Composition of electrode body 200)

[0093] like Figure 7 as well as Figure 8 As shown, the negative electrode plate 210, serving as the first electrode, has a different polarity than the positive electrode plate 240, serving as the second electrode. A negative electrode tab 230 (first electrode tab), composed of a negative electrode core 211, is provided at one end of the negative electrode plate 210 in the width direction. When the negative electrode plates 210 are stacked, multiple negative electrode tabs 230 are stacked to form a negative electrode tab assembly 220. The negative electrode tab assembly 220 is electrically connected to the first electrode. The length of each negative electrode tab 230 in the protruding direction among the multiple negative electrode plates 210 is appropriately adjusted considering the connection state between the negative electrode tab assembly 220 and the negative current collector 400A. The shape of the negative electrode tab 230 is not limited to... Figure 7 The illustrated shape.

[0094] like Figure 9 as well as Figure 10As shown, a positive electrode tab 260 (second electrode tab) composed of a positive electrode core 241 is provided at one end of the formed positive electrode plate 240 in the width direction. When the positive electrode plates 240 are stacked, multiple positive electrode tabs 260 are stacked to form a positive electrode tab assembly 250. The positive electrode tab assembly 250 is electrically connected to the second electrode. The length of each positive electrode tab 260 in the protruding direction among the multiple positive electrode plates 240 is appropriately adjusted considering the connection state between the positive electrode tab assembly 250 and the positive current collector 400B. The shape of the positive electrode tab 260 is not limited to... Figure 10 The illustrated shape.

[0095] A positive electrode protective layer 243 is provided at the base of the positive electrode tab 260. It is not necessary to provide a positive electrode protective layer 243 at the base of the positive electrode tab 260.

[0096] In a typical example, the thickness of the negative electrode tab 230 (one) is less than the thickness of the positive electrode tab 260 (one). In this case, the thickness of the negative electrode tab group 220 is less than the thickness of the positive electrode tab group 250.

[0097] (Connection structure between electrode 200 and current collector 400)

[0098] Reference Figure 11 as well as Figure 12 The connection structure between the electrode body 200 and the current collector 400 will be explained.

[0099] <Negative side>

[0100] Figure 11 This is the connection structure on the negative electrode side. The electrode body 200 includes a first electrode body 201 and a second electrode body 202. The first electrode body 201 and the second electrode body 202 respectively include a positive electrode (second electrode) and a negative electrode (first electrode). The electrode body 200 may also be composed of three or more electrode bodies.

[0101] Electrode 200 is formed by overlapping the first electrode 201 and the second electrode 202. The first electrode 201 and the second electrode 202 are arranged along the thickness direction (Y direction) of the first electrode 201 and the second electrode 202.

[0102] The first electrode 201 includes a negative electrode tab assembly 220 (first tab). The negative electrode tab assembly 220 is electrically connected to the current collector 410 (negative current collector) at its first end 205 in the X direction. The second electrode 202 includes a negative electrode tab assembly 270 (second tab). The negative electrode tab assembly 270 is electrically connected to the current collector 410 (negative current collector) at its third end 207 in the X direction.

[0103] The negative electrode tab assembly 220 has a bent portion 221 and a front end portion 222. The bent portion 221 is the portion of the negative electrode tab assembly 220 that bends relative to the front end portion 222 on the side connected to the first electrode. The front end portion 222 is the portion of the negative electrode tab assembly 220 located on the side opposite to the side connected to the first electrode.

[0104] The negative electrode tab assembly 220 has a first recess 220r that is recessed toward the negative electrode tab assembly 270 when bent. The negative electrode tab assembly 270 has a second recess 270r that is recessed toward the negative electrode tab assembly 220 when bent.

[0105] The first protrusion 652 of the spacer 600 described later is disposed within the first recess 220r of the first guide portion G1. Similarly, the second protrusion 662 of the spacer 600 described later is disposed within the second recess 270r of the second guide portion G2.

[0106] The negative electrode tab assembly 270 has a bent portion 271 and a front end portion 272. The bent portion 271 is the portion of the negative electrode tab assembly 270 that bends relative to the front end portion 272 on the side connected to the first electrode. The front end portion 272 is the portion of the negative electrode tab assembly 270 located on the side opposite to the side connected to the first electrode.

[0107] The negative electrode tab group 220 and the negative electrode tab group 270 are bent in opposite directions with their front ends 222 and 272 approaching each other. In this embodiment, the front ends 222 and 272 are separated, but this configuration is not limited to this; the front ends 222 and 272 may also contact each other.

[0108] Here, negative electrode tab group 220 is referred to as the first tab, and negative electrode tab group 270 is referred to as the second tab. The first tab means a negative electrode tab in one of the negative electrode tab groups 220 that is electrically connected to the current collector 410 (described later), and the second tab means a negative electrode tab in the other negative electrode tab group 270 that is electrically connected to the current collector 410. Therefore, the first and second tabs can be the negative electrode tabs located closest to the current collector 410, part of the core (metal foil) constituting the negative electrode plate, or independent components.

[0109] The negative current collector 400A electrically connects the negative terminal 301 to the negative electrode tab group 220 and the negative electrode tab group 270. In this embodiment, the negative current collector 400A is connected to the negative terminal 301 between the electrode body 200 and the sealing plate 120.

[0110] The negative current collector 400A includes current collector 410 and current collector 430.

[0111] Current collector 410 is a plate-shaped component. Current collector 410 has a long side in the Z direction and a short side in the Y direction. Current collector 410 is constructed as a single, integral component. Current collector 430 is also a plate-shaped component. Current collector 430 has a long side in the Z direction and a short side in the Y direction. Current collectors 410 and 430 are arranged side-by-side in the X direction. Thus, current collectors 410 and 430 are constructed as independent components.

[0112] Negative electrode tabs 220 and 270 are described later (see reference). Figure 17 The joint portion 411 is joined to the current collector 410. The joint portion 411 can be formed, for example, by ultrasonic welding, resistance welding, laser welding, or seam sealing. In this embodiment, the negative electrode tabs 220 and 270 and the current collector 410 are joined, for example, by ultrasonic joining.

[0113] The current collector 430 is joined to the current collector 410 at a joint (not shown) at its end located in the Z direction. The current collector 430 is connected to the negative terminal 301. The connection between the current collector 430 and the negative terminal 301 can be formed, for example, by seam sealing and / or welding.

[0114] The negative terminal 301 is exposed on the outside of the sealing plate 120. The negative terminal 301 is connected to the plate-shaped component 303. The negative terminal 301 includes a region 301a made of copper or copper alloy and a region 301b made of aluminum or aluminum alloy. Preferably, the region 301a made of copper or copper alloy is connected to the current collector 430.

[0115] The plate-shaped component 303 is located on the outside of the sealing plate 120. The plate-shaped component 303 is arranged along the sealing plate 120. The plate-shaped component 303 is conductive. The plate-shaped component 303 is arranged to ensure the connection area with the busbar, etc., that electrically connects the secondary battery 1 and other adjacent secondary batteries. The connection between the negative terminal 301 and the plate-shaped component 303 can be formed, for example, by laser welding.

[0116] An insulating component 510 is disposed between the plate-shaped component 303 and the sealing plate 120. An insulating component 520 is disposed between the negative terminal 301 and the sealing plate 120. An insulating component 530 is disposed between the current collector 430 and the sealing plate 120.

[0117] However, the negative terminal 301 can also be electrically connected to the sealing plate 120. The sealing plate 120 can function as the negative terminal 301.

[0118] A spacer 600 (first spacer) is disposed between the sealing plate 120 (first sealing plate) and the main body of the electrode body 200 (excluding the negative electrode tabs 220 and 270). The spacer 600 is made of an insulating resin component. The spacer 600 suppresses the movement of the electrode body 200 within the housing 100 in the X direction and suppresses damage to the negative electrode tabs 220, negative electrode tabs 270, and the electrode body 200. By disposing the negative electrode tabs 220 and 270 within the tab storage space 670 provided in the spacer 600, the spacer 600 can protect the negative electrode tabs 220 and 270 and prevent them from deforming into undesirable shapes. Furthermore, it can suppress undesirable short circuits (such as contact with conductive parts of different polarities) in the negative electrode tab group 220 and the negative electrode tab group 270.

[0119] A resin insulating sheet 700 (electrode support) is disposed between the electrode body 200 and the housing body 110. The insulating sheet 700 may be made of resin, for example. More specifically, the insulating sheet 700 may be made of polypropylene (PP), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyimide (PI), or polyolefin (PO).

[0120] <Positive side>

[0121] Figure 12 This is the connection structure on the positive electrode side. In this embodiment, the connection structure between the electrode body 200 and the current collector 400 on the positive electrode side of the secondary battery 1 differs from the structure on the negative electrode side in that the part corresponding to the current collector 410 on the negative electrode side is composed of two components.

[0122] The first electrode 201 includes a positive electrode tab group 250 (the second electrode tab). The positive electrode tab group 250 is electrically connected to the current collector 420 (the positive current collector) at its second end 206 in the X direction. The second electrode 202 includes a positive electrode tab group 280 (the first electrode tab). The positive electrode tab group 280 is electrically connected to the current collector 420 (the positive current collector) at its fourth end 208 in the X direction.

[0123] The positive electrode tab assembly 250 has a bent portion 251 and a front end portion 252. The bent portion 251 is the portion of the positive electrode tab assembly 250 that is bent relative to the front end portion 252 on the side where the second electrode is connected. The front end portion 252 is the portion of the positive electrode tab assembly 250 located on the side opposite to the side where the second electrode is connected.

[0124] The positive electrode tab assembly 250 has a first recess 250r that is recessed toward the positive electrode tab assembly 280 when bent. The positive electrode tab assembly 280 has a second recess 280r that is recessed toward the positive electrode tab assembly 250 when bent.

[0125] The second protrusion 662 of the spacer 600 described later is disposed within the first recess 250r of the first guide portion G1. Similarly, the first protrusion 652 of the spacer 600 described later is disposed within the second recess 280r of the second guide portion G2.

[0126] The positive electrode tab assembly 280 has a bent portion 281 and a front end portion 282. The bent portion 281 is the portion of the positive electrode tab assembly 280 that is bent relative to the front end portion 282 on the side connected to the second electrode. The front end portion 282 is the portion of the positive electrode tab assembly 280 located on the side opposite to the side connected to the second electrode.

[0127] The positive electrode tab group 250 and the positive electrode tab group 280 are bent in opposite directions with their front ends 252 and 282 approaching each other. In this embodiment, the front ends 252 and 272 are separated, but this configuration is not limited to this; the front ends 252 and 282 may also be in contact with each other.

[0128] Here, the positive electrode tab group 250 is referred to as the second tab, and the positive electrode tab group 280 is referred to as the first tab. The second tab means that it includes at least one positive electrode tab in the positive electrode tab group 250 that is electrically connected to the current collector 420 (described later), and the first tab means that it includes at least one positive electrode tab in the other positive electrode tab group 280 that is electrically connected to the current collector 420. Therefore, the first tab and the second tab can be the positive electrode tab located closest to the current collector 420, or they can be part of the core (metal foil) constituting the positive electrode plate, or they can be independent components.

[0129] The positive current collector 400B electrically connects the positive terminal 302 to the positive electrode tab group 250 and the positive electrode tab group 280. In this embodiment, the positive current collector 400B is connected to the positive terminal 302 between the electrode body 200 and the sealing plate 130.

[0130] The positive current collector 400B includes a current collector 420 (first current collector component) and a current collector 440 (second current collector component). A plate 460 is sandwiched between the current collector 420 (first current collector component) and the current collector 440 (second current collector component) as an insulating component, but is electrically connected at a location different from the cross-section shown in the figure.

[0131] The current collector 420 is a plate-shaped component. The current collector 420 has a long side in the Z direction and a short side in the Y direction. The current collector 420 consists of one current collector and another current collector; that is, the current collector 420 is composed of two components.

[0132] The positive electrode tab assembly 250 and the positive electrode tab assembly 280 are joined at the junction 421 described later (see reference). Figure 17The positive electrode tab 250 and the positive electrode tab 280 are joined to the current collector 420, which is composed of two components. The joining part 421 can be formed, for example, by ultrasonic welding, resistance welding, laser welding, or seam welding. In this embodiment, the positive electrode tab group 250 and the positive electrode tab group 280 are joined to the current collector 420, for example, by ultrasonic welding.

[0133] Current collector 440 is joined to current collector 420 at a joint (not shown) at its Z-direction end. Current collector 440 is connected to positive terminal 302. The connection between current collector 440 and positive terminal 302 can be formed, for example, by seam sealing and / or welding.

[0134] The positive terminal 302 is exposed on the outside of the sealing plate 130 and is positioned such that it reaches the current collector 440 of the positive current collector 400B disposed on the inner surface of the sealing plate 130. The positive terminal 302 is connected to the plate-shaped member 304.

[0135] The plate-shaped component 304 is located on the outside of the sealing plate 130. The plate-shaped component 304 is arranged along the sealing plate 130. The plate-shaped component 304 is conductive. The plate-shaped component 304 is arranged to ensure the connection area with the busbar, etc., that electrically connects the secondary battery 1 and other adjacent secondary batteries. The connection between the positive terminal 302 and the plate-shaped component 304 can be formed, for example, by laser welding.

[0136] An insulating component 510 is disposed between the plate-shaped component 304 and the sealing plate 130. An insulating component 520 is disposed between the positive terminal 302 and the sealing plate 130. An insulating component 470 is disposed between the current collector 440 and the sealing plate 130.

[0137] However, the positive terminal 302 can also be electrically connected to the sealing plate 130. The sealing plate 130 can function as the positive terminal 302.

[0138] A spacer 600 (second spacer) is disposed between the sealing plate 130 (second sealing plate) and the main body of the electrode body 200 (excluding the positive electrode tabs 250 and 280). The spacer 600 is made of an insulating resin component. The spacer 600 suppresses movement of the electrode body 200 within the housing 100 in the X direction and suppresses damage to the positive electrode tabs 250 and 280 and the electrode body 200. The positive electrode tabs 250 and 280 pass through the tab storage space 670 provided in the spacer 600, thereby protecting the positive electrode tabs 250 and 280 from deformation into undesirable shapes. Furthermore, it can suppress undesirable short circuits (such as contact with conductive components of different polarities) of the positive electrode tabs 250 and 280.

[0139] The separator 600, which is disposed on the negative electrode side and the positive electrode side, is made of resin, for example. The material of the separator 600 is, for example, polypropylene (PP), polyphenylene sulfide (PPS), polybutylene terephthalate (PBT), or ethylene propylene rubber (EPDM).

[0140] An insulating sheet 700 (electrode support) made of resin is disposed between the electrode body 200 and the housing body 110.

[0141] (600 units of isolation material)

[0142] Reference Figures 13 to 15 The shape of the separator 600 will be described. In this embodiment, the separator 600 disposed on the side of the negative electrode tab group 220 and the negative electrode tab group 270 has the same shape as the separator 600 disposed on the side of the positive electrode tab group 250 and the positive electrode tab group.

[0143] The separator 600 has a rectangular shape along the inner circumferential surface of the housing body 110, and like the housing body 110, its height direction (Z direction) is longer than the thickness direction (Y direction) of the secondary battery 1.

[0144] The spacer 600 includes a first base 610. The first base 610 is surrounded by a first peripheral wall 621, a second peripheral wall 622, a third peripheral wall 623, and a fourth peripheral wall 624. Since the fourth peripheral wall 624 is located on the inner side, it is positioned lower than the other peripheral walls. At the end edge of the first peripheral wall 621 opposite to the first base 610, protrusions 627 and 628 are provided at a predetermined distance.

[0145] A first guide portion G1 and a second guide portion G2 are provided on the first base 610, arranged opposite to each other and extending in one direction (Z direction). One end of the first guide portion G1 is fixed to the first base 610, and the other end of the first guide portion G1 is open. One end of the second guide portion G2 is fixed to the first base 610, and the other end of the second guide portion G2 is open.

[0146] The first guide portion G1 includes a first connecting peripheral wall 650 extending continuously from the second peripheral wall 622 and a second connecting peripheral wall 651 on the other end side of the first connecting peripheral wall 650 facing the second guide portion G2. The second connecting peripheral wall 651 is provided with a protrusion 647 identical to the protrusions 627 and 628 provided on the first peripheral wall 621. A first protrusion 652 extending (in the Z direction) from the second peripheral wall 622 toward the second connecting peripheral wall 651 is provided on the surface of the first connecting peripheral wall 650 opposite to the side of the second guide portion G2.

[0147] The second guide portion G2 includes a third connecting peripheral wall 660 extending continuously from the third peripheral wall 623 and a fourth connecting peripheral wall 661 on the other end of the third connecting peripheral wall 660 facing the first guide portion G1. The fourth connecting peripheral wall 661 is provided with a protrusion 648 that is the same as the protrusions 627 and 628 provided on the first peripheral wall 621. On the surface of the third connecting peripheral wall 660 opposite to the side of the first guide portion G1, a second protrusion 662 extending (in the Z direction) from the third peripheral wall 623 toward the fourth connecting peripheral wall 661 is provided.

[0148] The second connecting peripheral wall 651 and the fourth connecting peripheral wall 661 are not connected to each other, thus forming a connecting space 680. The connecting space 680 is the space that connects the tab storage space 670 (described later) to the external space of the separator 600. The preferred dimensions of the connecting space 680 located between the second connecting peripheral wall 651 and the fourth connecting peripheral wall 661 will be described later.

[0149] In the isolation element 600 having the above-described configuration, a tab storage space 670 is defined, which is surrounded by a fourth peripheral wall 624, a first connecting peripheral wall 650, a second connecting peripheral wall 651, and a third connecting peripheral wall 660.

[0150] In the secondary battery manufacturing process described later, a storage process is adopted in which the first electrode and the second electrode are stored in the electrode storage space 670 via the connecting space 680, and a bending process is adopted after the storage process in which the first electrode is bent by the first guide G1 facing the main outer surface of the first electrode and the second electrode is bent by the second guide G2 facing the main outer surface of the second electrode.

[0151] like Figure 15 As shown, since the first protrusion 652, which is located on the inner side of the first connecting peripheral wall 650, abuts against the first electrode tab during the manufacturing process of the secondary battery, its outer surface can be curved. Furthermore, a first concave curved surface 653 can be provided on the sealing plate 120 (first sealing plate) side (upper side in the figure) of the first protrusion 652.

[0152] By making the outer surface of the first protrusion 652 curved, the first electrode tab can be deformed into the prescribed shape more stably, and damage to the first electrode tab can be suppressed when it comes into contact with the first electrode tab. Furthermore, by providing the first concave curved surface 653, the first electrode tab can be deformed into the prescribed shape more stably, and damage to the first electrode tab can be further suppressed when it comes into contact with the first electrode tab.

[0153] Similarly, the second protrusion 662, located on the inner side of the third connecting peripheral wall 660, is also similar to the first connecting peripheral wall 650 described above. Since it abuts against the second electrode tab during the secondary battery manufacturing process, its outer surface can be curved. Furthermore, a second concave curved surface 663 can be provided on the sealing plate 120 (first sealing plate) side (upper side in the figure) of the second protrusion 662.

[0154] By making the outer surface of the second protrusion 662 curved, the second tab can be deformed into the prescribed shape more stably, thus suppressing damage to the second tab when it comes into contact with it. Furthermore, by providing the second concave curved surface 663, the second tab can be deformed into the prescribed shape more stably, further suppressing damage to the second tab when it comes into contact with it.

[0155] (Manufacturing process of secondary battery 1 (electrode fabrication process))

[0156] The manufacturing method of the secondary battery according to this embodiment will be described below.

[0157] like Figure 16 As shown, in the manufacturing method of the secondary battery according to this embodiment, the first electrode body 201 and the second electrode body 202 are first manufactured (S1 step). Preferably, a portion of the front end of the negative electrode tab group 220, the positive electrode tab group 250, the negative electrode tab group 270 and the positive electrode tab group 280 is cut off in such a way that the length of the front end is the same when they are bundled.

[0158] like Figures 16 to 18 As shown, after the first electrode body 201 and the second electrode body 202 are fabricated, the positive electrode tabs 250 and 280 are joined to the current collector 420 (S2 process). The positive electrode tabs 250 and 280 are joined to the current collector 420 at the joining portion 421.

[0159] Next, the first electrode 201, the current collector 410, and the second electrode 202 are arranged sequentially along the DR1 direction. A negative electrode tab assembly 220 is arranged on one side of the current collector 410 along the DR1 direction. With the negative electrode tab assembly 270 arranged on the other side of the current collector 410 along the DR1 direction, the negative electrode tab assembly 220 and the negative electrode tab assembly 270 are joined to the current collector 410 (step S3). The negative electrode tab assembly 220 and the negative electrode tab assembly 270 are joined to the current collector 410 at the joining portion 411.

[0160] In the height direction of the first electrode 201 and the second electrode 202, the current collectors 410 and 420 are disposed offset to one side from the center of the first electrode 201 and the second electrode 202. Therefore, since the current collectors can be made shorter, they can be made smaller. The current collectors 410 and 420 are not limited to this configuration. The current collectors 410 and 420 may also be disposed at the center of the first electrode 201 and the second electrode 202 in the height direction.

[0161] The order of the processes for connecting the first electrode 201 and the second electrode 202 to the current collector 410 and the current collector 420, respectively, is not limited to the above and can be changed. Preferably, the process of connecting the first electrode 201 and the second electrode 202 to the current collector 420 is performed before the process of aligning the first electrode 201 and the second electrode 202, which will be described later, and preferably before the process of connecting the first electrode 201 and the second electrode 202 to the current collector 410.

[0162] Next, after the negative electrode tab group 220 and the negative electrode tab group 270 are joined to the current collector 410, in the thickness direction of the first electrode body 201 and the second electrode body 202 ( Figure 17 as well as Figure 18 In the direction orthogonal to DR1, the negative electrode tab group 220 and the negative electrode tab group 270 are bent so that the first electrode body 201 and the second electrode body 202 overlap (S4 process). That is, the first electrode body 201 and the second electrode body 202 are brought together.

[0163] "Making the first electrode and the second electrode overlap" can mean that the first electrode and the second electrode are directly overlapped, or that other components are placed between the first electrode and the second electrode. The first electrode and the second electrode can be fixed by tape or the like, or they can be left unfixed. Furthermore, the first electrode, the current collector, and the second electrode can be arranged in a non-linear manner in the DR1 direction, or the first electrode or the second electrode can be tilted relative to the DR1 direction with respect to the current collector.

[0164] Negative electrode tabs 220 and 270 are bent with their front ends facing each other. Positive electrode tabs 250 and 280 are also bent with their front ends facing each other.

[0165] like Figure 16 as well as Figure 19 As shown, the separator 600 and the insulating sheet 700 are assembled onto the electrode body 200 (S5 process).

[0166] like Figure 19As shown, an electrode body 200 is disposed on an insulating sheet 700, and spacers 600 are disposed at both ends of the electrode body 200. They are arranged such that the first side portion 111 is the upper side, the second side portion 112 is the lower side, and the second side portion 112 is one side of the insulating sheet 700. The spacer 600 is configured such that its long side extends vertically, and the side with the connecting space 680 is the upper side.

[0167] like Figure 20 As shown, an insulating material 600 is placed on top of an insulating sheet 700. In the insulating material 600, since the positive electrode tab assembly 250 (second tab) and the positive electrode tab assembly 280 (first tab) pass through the tab receiving space 670 via the connecting space 680, the preferred dimension L1 between the second connecting peripheral wall 651 and the fourth connecting peripheral wall 661 is approximately 10 mm. Furthermore, in the receiving space for the positive electrode tab assembly 250 and the positive electrode tab assembly 280, the dimension L2 between the first protrusion 652 and the second protrusion 662 can be approximately 15 mm.

[0168] Next, refer to Figure 21 The positive electrode tab assembly 250 and the positive electrode tab assembly 280 are stored in the tab storage space 670 (the electrode body 200 is moved in the direction of arrow R2 in the figure. / Storage process).

[0169] At this point, the first protrusion 652 of the first connecting peripheral wall 650 is positioned opposite the main outer surface of the positive electrode tab group 250 (the second electrode tab), and the second protrusion 662 of the third connecting peripheral wall 660 is positioned opposite the main outer surface of the positive electrode tab group 280 (the first electrode tab). Here, the main outer surface refers to the surface with a large area rather than the side end surface of the electrode tab.

[0170] Although the description based on the illustration is omitted for the negative electrode side, after the separator 600 is assembled on the side of the negative electrode tab group 220 (first tab) and the negative electrode tab group 270 (second tab), it is in a state in which the first protrusion 652 of the first connecting peripheral wall 650 is positioned opposite to the main outer surface of the negative electrode tab group 220 (first tab), and the second protrusion 662 of the third connecting peripheral wall 660 is positioned opposite to the main outer surface of the negative electrode tab group 270 (second tab).

[0171] In the above process, since the negative electrode tab group 220, negative electrode tab group 270, positive electrode tab group 250 and positive electrode tab group 280, which serve as the first electrode tab and the second electrode tab, can be arranged in the electrode tab storage space 670 through the communicating space 680 of the separator 600, the separator 600 can be easily assembled into the electrode body 200 compared to the case where the separator is provided with a hole through which the electrode tabs are inserted and the electrode tabs are inserted through the hole.

[0172] Preferably, the negative electrode tab group 220 and the negative electrode tab group 270 are inserted into the tab receiving space 670 via the connecting space 680 with the front end face of one of the stacked end faces (the face where each negative electrode tab is disposed) of the negative electrode tab group 220 and the negative electrode tab group 270 as the front end face. This effectively suppresses damage to the negative electrode tab group 220 and the negative electrode tab group 270. In addition, after the negative electrode tab group 220 and the negative electrode tab group 270 are inserted into the tab receiving space 670, the first guide part G1 faces the main outer surface of the negative electrode tab group 220, and the second guide part G2 faces the main outer surface of the negative electrode tab group 270.

[0173] Then, after assembling the separators 600 on the negative and positive sides of the electrode body 200 respectively, the insulating sheet 700 is then oriented towards... Figure 21 The electrode body 200 and the spacers 600 on both sides are covered by an insulating sheet 700 by bending in the direction of arrow R4. Thus, with spacers 600 arranged on both sides of the electrode body 200, the electrode body 200 and the spacers 600 on both sides are covered by an insulating sheet 700.

[0174] By using the insulating sheet 700 to cover the insulating material 600, the negative electrode tab group and the positive electrode tab group located inside the insulating material 600 can be more reliably protected.

[0175] The insulating sheet 700 is fixed to the separators 600 on both sides. The insulating sheet 700 can be fixed to the separators 600 by means of welding, bonding, tape, etc.

[0176] like Figure 22 As shown, in this embodiment, the insulating sheet 700 covers the entire circumference of the electrode body 200 and the separator 600 in the X direction. The insulating sheet 700 does not necessarily need to cover the entire surface of the electrode body 200. Preferably, the insulating sheet 700 covers at least 50% of the outer surface of the electrode body, more preferably at least 70%. The insulating sheet 700 preferably covers at least four of the six surfaces of the generally cuboid (flat) electrode body 200, excluding the two surfaces where the negative electrode tab group 220 and the positive electrode tab group 250 are formed respectively. Preferably, the protrusions 627, 628, 647, and 648 provided on the separator 600 are exposed from the insulating sheet 700.

[0177] like Figure 22 As shown, next, current collector 410 is electrically connected to negative terminal 301 via current collector 430 (S6 step). S6 step can also be performed before S5 step.

[0178] Specifically, such as Figure 22As shown, the negative electrode tab group 220 and the negative electrode tab group 270 are bent so that their front ends 222 and 272 are opposite to each other.

[0179] The negative terminal 301 and the current collector 430 are mounted to the sealing plate 120 via an insulating component. The current collector 430 and the current collector 410 are brought into contact in the X direction. The connection of the plate-shaped component 303 to the negative terminal 301 can be made at any time. The current collector 430 and the current collector 410 are joined by laser welding between the sealing plate 120 and the insulating sheet 700.

[0180] Next, as Figure 23 As shown, with the current collector 420 side as the front end, the separator 600 and the electrode body 200 are inserted into the housing body 110 through the opening 113 (S7 process).

[0181] Next, as Figure 24 As shown, by bringing the sealing plate 120 close to the main body of the electrode body 200 (first electrode body 201 and second electrode body 202) from the state of extending from the negative electrode tab group 220 and the negative electrode tab group 270, the negative electrode tab group 220 and the negative electrode tab group 270 are bent. Figure 25 (As shown in the diagram). The negative electrode tabs 220 and 270 are bent along the shape of the separator 600 in such a way that the folded-back portions of the bends 221 and 271 approach the housing body 110 in the Y direction.

[0182] After the sealing plate 120 abuts against the housing body 110, the sealing plate 120 is pre-engaged to the housing body 110. Through pre-engagement, the sealing plate 120 is partially engaged to the opening 113 of the housing body 110. Thus, the sealing plate 120 is positioned relative to the housing body 110.

[0183] When the electrode body 200 is inserted into the housing body 110, the electrode body 200 can be pulled from the current collector 420 side or pressed from the current collector 410 side. When the electrode body 200 is pressed from the current collector 410 side, both the negative electrode tab group 220 and the negative electrode tab group 270 can be bent simultaneously.

[0184] During the bending process of the negative electrode tab assembly 220 and the negative electrode tab assembly 270 (bending process), the negative electrode tab assembly 220 and the negative electrode tab assembly 270 are bent with the first connecting peripheral wall 650 facing the main outer surface of the negative electrode tab assembly 220 (first tab) and the third connecting peripheral wall 660 facing the main outer surface of the negative electrode tab assembly 270 (second tab). This effectively prevents the negative electrode tab assembly 220 and the negative electrode tab assembly 270 from deforming into undesirable shapes, such as significant outward deformation and partial deformation into a shape that contacts the inner surface of the housing body 110.

[0185] More preferably, the negative electrode tabs 220 and 270 are bent while the first connecting peripheral wall 650 is in contact with the main outer surface of the negative electrode tab assembly 220 and the third connecting peripheral wall 660 is in contact with the main outer surface of the negative electrode tab assembly 270. This makes it easier to bend the negative electrode tabs 220 and 270 into a predetermined shape.

[0186] Furthermore, it is even more preferable that the negative electrode tab group 220 and the negative electrode tab group 270 be bent while the first protrusion 652 provided on the first connecting peripheral wall 650 abuts against the main outer surface of the negative electrode tab group 220 and the second protrusion 662 provided on the third connecting peripheral wall 660 abuts against the main outer surface of the negative electrode tab group 270.

[0187] The result is, as Figure 25 As shown, after the sealing plate 120 is positioned on the housing body 110, the negative electrode tab group 220 (first electrode tab) has a first recess 220r that is recessed toward the negative electrode tab group 270 (second electrode tab) in a bent state, and the negative electrode tab group 270 (second electrode tab) has a second recess 270r that is recessed toward the negative electrode tab group 220 (first electrode tab) in a bent state.

[0188] Furthermore, the first protrusion 652 of the first connecting peripheral wall 650 is disposed within the first recess 220r, and the second protrusion 662 of the third connecting peripheral wall 660 is disposed within the second recess 270r.

[0189] By providing a first protrusion 652 at a position opposite to the main outer surface of the negative electrode tab group 220 (first tab) and a second protrusion 662 at a position opposite to the main outer surface of the negative electrode tab group 270 (second tab), the negative electrode tab group 220 and the negative electrode tab group 270 can be easily bent into a predetermined shape, thereby improving the assemblability of the secondary battery.

[0190] Next, after inserting the electrode body 200 into the housing body 110, the current collector 420 is electrically connected to the positive terminal 302 (S8 process).

[0191] Specifically, the positive terminal 302 is mounted to the sealing plate 130 via an insulating component. After the first electrode 201 and the second electrode 202 are inserted into the housing body 110, the current collector 450 abuts against the current collector 420 protruding from the opening 114 in the X direction. The connection of the plate-shaped component 304 to the positive terminal 302 can be made at any time.

[0192] The positive electrode tab group 250 and positive electrode tab group 280 connected to the current collector 420 are bent so that their front ends 252 and 282 are opposite to each other. Figure 12 As shown, the positive electrode tabs 250 and 280 are bent along the shape of the separator 600 such that the folded-back portions of the bends 251 and 281 approach the housing body 110 in the Y direction.

[0193] In the bending process of the positive electrode tab group 250 and positive electrode tab group 280 on the positive electrode side, based on the same process as the negative electrode tab group 220 and negative electrode tab group 270 on the negative electrode side, by providing a first protrusion 652 at a position opposite to the main outer surface of the positive electrode tab group 280 (first tab) and a second protrusion 662 at a position opposite to the main outer surface of the positive electrode tab group 250 (second tab), it is possible to facilitate the easy deformation of the positive electrode tab group 250 and positive electrode tab group 280 into a specified bending shape, thereby improving the assemblability of the secondary battery.

[0194] like Figure 25 As shown, after the separator 600 and the electrode body 200 are inserted into the housing body 110, the sealing plate 130 (first sealing plate) and the sealing plate 120 (second sealing plate) are joined to the housing body 110 (S9 process).

[0195] Specifically, after the sealing plate 130 abuts against the housing body 110, the sealing plate 130 is pre-welded to the housing body 110. Through pre-joining, the sealing plate 130 is partially joined to the opening 114 of the housing body 110. Thus, the sealing plate 130 is positioned relative to the housing body 110.

[0196] Next, sealing plates 120 and 130 are joined to the housing body 110. Sealing plate 120 seals the opening 113 of the housing body 110, and sealing plate 130 seals the opening 114 of the housing body 110. Thus, the first electrode 201 and the second electrode 202 are housed in the housing 100.

[0197] After the above-described processes, leak checks and other inspections are performed (S10 process). After the leak check, the secondary battery 1 is dried in order to remove moisture from the casing 100.

[0198] Next, with the sealing plate 130 (second sealing plate) positioned above the sealing plate 120 (first sealing plate) in the vertical direction and the separator 600 (first separator) positioned below the electrode body 200, electrolyte is injected into the housing 100 through the injection hole provided on the sealing plate 130 (second sealing plate) (step S11). Because the separator 600 is provided around the injected electrolyte, damage to the electrode body 200 and the like can be suppressed even if the electrolyte is forcefully injected into the housing 100. Therefore, compared to the case where the separator 600 is not provided, the secondary battery 1 of this embodiment can inject electrolyte in a shorter time.

[0199] During liquid injection, it is preferable that the angle between the main surface of the sealing plate and the vertical direction is approximately 90±45°. More preferably, the main surface of the sealing plate is perpendicular to the vertical direction.

[0200] The electrode body 200 disposed within the housing 100 preferably weighs 500g or more, more preferably 1kg or more. The weight of the electrode body 200 excludes the electrolyte. When there are multiple electrode bodies 200, the weight is the total weight. Even if the electrode body 200 is heavy, it can be supported by the separator 600 (first separator).

[0201] Then, venting and charging are performed. During venting and charging, the injection port 134 can be pre-sealed. Then, the injection port 134 is sealed, and the secondary battery 1 is completed.

[0202] In the secondary battery 1 and its manufacturing method according to Embodiment 1 of this technology, the first electrode and the second electrode can be disposed in the electrode storage space 670 via the communication space 680 of the separator 600.

[0203] As a result, compared to the case where the separator is provided with a hole through which the electrode tabs are inserted and the electrode tabs are inserted into that hole, the separator 600 can be easily assembled to the electrode body 200. Consequently, the assemblability of the secondary battery can be improved, and thus, a highly reliable secondary battery can be provided.

[0204] In the spacer 600, when an electrode body 200 is subjected to force from the spacer 600 due to the electrode tabs being disposed between the first base 610 and the second connecting peripheral wall 651 and the fourth connecting peripheral wall 661, the force applied to the electrode body 200 from the spacer 600 can be dispersed, and damage to the end of the electrode body 200 can be suppressed.

[0205] Since the electrode body 200 can be clamped by the isolation material 600 between the sealing plates on both sides and the electrode body 200, the movement of the electrode body 200 within the housing 100 can be suppressed.

[0206] In the electrolyte injection process, since the electrolyte is injected into the housing 100 through the injection hole 134 with the separator 600 positioned below the electrode body 200, deformation of the separator 600 can be suppressed, thus stably supporting the electrode body 200. This helps to prevent damage to the electrode tabs and the electrode body 200. Furthermore, because the electrode body 200 is stably supported, even if the electrolyte injection speed increases, the electrode body 200 will not move unnecessarily inside the housing 100, allowing for rapid electrolyte injection and improving electrolyte injection performance.

[0207] In the manufacturing method of the secondary battery 1 according to Embodiment 1 of this technology, since the insulating sheet 700, which is easily slidable by covering the electrode body 200 and the separator 600, is located on the outer peripheral side, the electrode body 200 and the separator 600 can be easily inserted into the interior of the housing body 110. Damage to the electrode tabs and the electrode body 200 can be effectively suppressed by the insulating sheet 700.

[0208] (Other implementation methods)

[0209] The following is for reference Figures 27 to 31 Other forms of isolation materials will be described.

[0210] (Implementation Method 2: Isolator 600A)

[0211] Reference Figure 27 The form of the spacer 600A in Embodiment 2 will be described. The basic structure of the spacer 600A is the same as that of the spacer 600 described above. In the spacer 600A, curved surfaces R10 are provided on the surfaces of the second connecting peripheral wall 651 and the fourth connecting peripheral wall 661 that face each other.

[0212] By providing curved surfaces R10 on the second connecting peripheral wall 651 and the fourth connecting peripheral wall 661, when the first electrode and the second electrode are disposed in the electrode storage space 670 via the connecting space 680, even when the first electrode and the second electrode are in contact with the second connecting peripheral wall 651 and the fourth connecting peripheral wall 661, the first electrode and the second electrode can move smoothly and damage to the first electrode and the second electrode can be suppressed.

[0213] (Implementation method 3: Isolator 600B)

[0214] Reference Figure 28 as well as Figure 29 The form of the spacer 600B in Embodiment 3 will be described. The basic structure of the spacer 600B is the same as that of the spacer 600 described above. In the spacer 600B, the connection portion between the second peripheral wall 622 and the first connecting peripheral wall 650 is configured to allow the first guide portion G1 to move in a direction of approach relative to the second guide portion G2 using a hinge RH1 made of a thin-walled member that is thinner than the periphery (first state / reference). Figure 28 ) and the direction away (Second state / reference) Figure 29 )move.

[0215] Similarly, the connection between the third peripheral wall 623 and the third connecting peripheral wall 660 is configured to allow the second guide portion G2 to approach the first guide portion G1 in a direction that is made of a hinge RH2 composed of a thin-walled component that is thinner than the periphery (first state / reference). Figure 28 ) and the direction away (Second state / reference) Figure 29 (Refer to) move.

[0216] The wall thickness of hinges RH1 and RH2 can be less than 1 mm. However, hinges RH1 and RH2 are not limited to a thin wall structure; they can be movable areas that allow the hinges to function, as long as they have a narrower slit than other areas.

[0217] Thus, in the spacer 600B of Embodiment 3, the first electrode and the second electrode can be housed in the electrode housing space 670 while deforming the spacer 600B in a state where the width of the communicating space 680 is increased, and then the spacer 600B is deformed in a state where the width of the communicating space 680 is decreased. That is, by expanding the first guide portion G1 and the second guide portion G2 from the first state to the second state, the communicating space 680 can be expanded. As a result, the first electrode and the second electrode can be moved smoothly through the communicating space 680 to the electrode housing space 670, and damage to the first electrode and the second electrode is suppressed.

[0218] In the case where a configuration is adopted in which the first guide section G1 and the second guide section G2 are expanded from the first state to the second state, the first state (refer to...) Figure 28 The distance S1 between the second connecting perimeter wall 651 and the fourth connecting perimeter wall 661 of the connected space 680 under the ) can be minimized as much as possible.

[0219] (Implementation Method 4: Isolator 600C)

[0220] Reference Figure 30 as well as Figure 31 The form of the spacer 600C in Embodiment 4 will be described. The basic structure of the spacer 600C is the same as that of the spacer 600B described above, and it is configured such that the first guide portion G1 and the second guide portion G2 can be moved in an approaching direction (first state / reference). Figure 30 ) and the direction away (Second state / reference) Figure 31 )move.

[0221] Furthermore, in this separator 600C, the second connecting peripheral wall 651 and the fourth connecting peripheral wall 661 are configured to be connectable. The second connecting peripheral wall 651 is provided with a first engaging portion T21, and the fourth connecting peripheral wall 661 is provided with a second engaging portion T22. In this embodiment, the first engaging portion T21 and the second engaging portion T22 are configured to be in a selectable engaging state (…). Figure 30 ) and non-locking state ( Figure 31 ).

[0222] In addition to interlocking and locking, the engagement of the first engaging part T21 and the second engaging part T22 can also be achieved using techniques such as adhesive bonding or fusion bonding, provided that once the engaging state is selected, there is no need to return to the non-engaged state.

[0223] The same effect as that of the aforementioned isolation material 600B can be obtained in this isolation material 600C.

[0224] While embodiments of the present invention have been described, they should be considered illustrative rather than restrictive in all respects. The scope of the invention is defined by the technical solutions and is intended to include all equivalents and modifications within that scope.

Claims

1. A method for manufacturing an energy storage device, the energy storage device comprising: The electrode body includes a first electrode and a second electrode with a polarity different from that of the first electrode; and The housing contains the electrode body. The housing includes a housing body having a first opening at one end and a first sealing plate that seals the first opening. The electrode body includes a first tab and a second tab at the end on the side of the first sealing plate, which are electrically connected to the first electrode, respectively. A first separator is disposed between the first sealing plate and the electrode body. The first electrode and the second electrode are respectively arranged in a bent state within the electrode storage space provided in the first separator. The first separator includes a first guide portion and a second guide portion. The first guide portion and the second guide portion are arranged opposite to each other. The electrode storage space is disposed between the first guide portion and the second guide portion. The main outer surface of the first electrode ear is opposite to the first guide portion. The main outer surface of the second electrode ear is opposite to the second guide portion. The method for manufacturing the energy storage device is characterized by having: The electrode body manufacturing process involves manufacturing the electrode body having the first electrode tab and the second electrode tab; In the storage process, after the electrode body manufacturing process, the first insulating material, having a communicating space connecting the electrode tab storage space to the outer space of the first insulating material, is used to store the first electrode tab and the second electrode tab in the electrode tab storage space via the communicating space; and In the bending process, after the storage process, the first electrode and the second electrode are bent with the first guide facing the main outer surface of the first electrode and the second guide facing the main outer surface of the second electrode.

2. The method for manufacturing the energy storage device according to claim 1, characterized in that, The process includes a step of connecting at least one of the first tab and the second tab to the current collector prior to the storage step.

3. The method for manufacturing the energy storage device according to claim 1, characterized in that, The first electrode has a first recess that is recessed toward the second electrode when bent. The second electrode has a second recess that is recessed toward the first electrode when bent. The first guide portion has a first protrusion. The second guide portion has a second protrusion. The first protrusion is disposed within the first recess. The second protrusion is disposed within the second recess.

4. The method for manufacturing the energy storage device according to claim 3, characterized in that, The first guide portion has a first concave curved surface on one side of the first sealing plate of the first protrusion. The second guide portion has a second concave curved surface on one side of the first sealing plate of the second protrusion.

5. The method for manufacturing the energy storage device according to claim 1, characterized in that, This includes an insertion process that, after the storage process, inserts the electrode body and the first spacer into the housing body. After the insertion process, in the bending process, the first guide portion abuts against the first electrode tab and the second electrode tab abuts against the second guide portion while bending the first electrode tab and the second electrode tab.

6. The method for manufacturing the energy storage device according to claim 1, characterized in that, The main body of the housing has a second opening at one end. The second opening is sealed by the second sealing plate.

7. The method for manufacturing the energy storage device according to claim 1, characterized in that, The first separator is disposed at one end of the electrode body. The electrode body and the first isolator are covered by an insulating sheet.

8. The method for manufacturing the energy storage device according to claim 7, characterized in that, have: The first configuration step involves placing the first separator onto the insulating sheet; The second configuration step involves, after the first configuration step, configuring the first electrode tab and the second electrode tab in the electrode tab storage space, and configuring the electrode body on the insulating sheet; as well as The coating process involves covering the electrode body and the first separator with the insulating sheet after the second configuration process.

9. The method for manufacturing the energy storage device according to claim 1, characterized in that, In the region of the connected space defined by the first guide portion and the second guide portion, the opposing regions of the first guide portion and the second guide portion are mutually convex curved shapes or chamfered corners.

10. The method for manufacturing an energy storage device according to claim 1, characterized in that, In the storage process, With the first isolator deformed by increasing the width of the connected space, the first electrode and the second electrode are housed in the electrode housing space. Then, the first isolator is deformed in such a way that the width of the connected space decreases.

11. An energy storage device, characterized in that, have: The electrode body includes a first electrode and a second electrode with a polarity different from that of the first electrode; and The housing contains the electrode body. The housing includes a housing body having a first opening at one end and a first sealing plate that seals the first opening. The electrode body includes a first tab and a second tab, which are electrically connected to the first electrode, at one end on the side of the first sealing plate. The first electrode tab and the second electrode tab are electrically connected to the first electrode in a bent state. A first separator is disposed between the first sealing plate and the electrode body. The first separator includes a main body and a first guide portion and a second guide portion arranged in a manner connected to and opposite to the main body. The first guide portion and the second guide portion define the electrode storage space and define a connecting space that connects the electrode storage space to the external space. The communication space is defined on the side opposite to the main body portion, separated by the first guide portion and the second guide portion. The first electrode tab is bent when the first guide portion faces the main outer surface of the first electrode tab. The second electrode is bent when the second guide portion faces the main outer surface of the second electrode.

12. The energy storage device according to claim 11, characterized in that, The first electrode has a first recess that is recessed toward the second electrode when bent. The second electrode has a second recess that is recessed toward the first electrode when bent. The first guide portion has a first protrusion. The second guide portion has a second protrusion. The first protrusion is disposed within the first recess. The second protrusion is disposed within the second recess.

13. The energy storage device according to claim 12, characterized in that, The first guide portion has a first concave curved surface on one side of the first sealing plate of the first protrusion. The second guide portion has a second concave curved surface on one side of the first sealing plate of the second protrusion.

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