Manufacturing method for energy storage elements

Abstract

The present invention provides a method for manufacturing an energy storage element that facilitates the insertion of the electrode body into the case body. [Solution] The solution involves inserting an electrode body 2, on which electrodes are stacked, into a case body having an opening in a first direction, through the opening, and the insertion of the electrode body is performed while maintaining a state in which the electrode body is compressed in a second direction Z that intersects the first direction.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a power storage element including an electrode body and a case for housing the electrode body.

Background Art

[0002] Patent Document 1 discloses a method for manufacturing a secondary battery in which an electrode body is inserted into a battery case to construct a battery assembly.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to increase the charging density of the power storage element, it is desired to make the electrode body inserted into the case body larger, but it becomes difficult to insert the electrode body into the case body.

[0005] Therefore, an object of the present invention is to provide a method for manufacturing a power storage element in which an electrode body can be easily inserted into a case body.

Means for Solving the Problems

[0006] The method for manufacturing a power storage element according to the present embodiment includes: inserting an electrode body in which electrodes are stacked into a case body having an opening in a first direction from the opening, wherein the insertion of the electrode body is performed while maintaining a state in which the electrode body is compressed in a second direction intersecting the first direction.

Effects of the Invention

[0007] According to the present embodiment, it is possible to provide a method for manufacturing a power storage element in which an electrode body can be easily inserted into a case body.

Brief Description of the Drawings

[0008] [Figure 1] Figure 1 is a view of the energy storage element according to this embodiment, as seen from the Y-axis direction. [Figure 2] Figure 2 is an exploded perspective view of the energy storage element. [Figure 3] Figure 3 is a view of the electrode body of the energy storage element as seen from the X-axis direction. [Figure 4] Figure 4 is a flowchart of the manufacturing method for the energy storage element. [Figure 5] Figure 5 shows the two sheet-like members and electrode body that make up the housing. [Figure 6] Figure 6 shows the state in which the container is formed by sealing the two sheet-like members. [Figure 7] Figure 7 shows the state in which both ends of the container are cut off. [Figure 8] Figure 8 shows a housing with both ends open, with the electrode body inside. [Figure 9] Figure 9 shows an electrode body surrounded by an insulating member made of a single sheet-like material. [Modes for carrying out the invention]

[0009] (1) A method for manufacturing an energy storage element according to one embodiment of the present invention is: The device comprises inserting an electrode body, in which electrodes are stacked, into a case body having an opening in the first direction through the opening, The insertion of the electrode body is performed while maintaining a state in which the electrode body is compressed in a second direction intersecting the first direction.

[0010] According to a method for manufacturing an energy storage element according to one embodiment of the present invention, when inserting the electrode body into the case body, the electrode body is kept in a compressed state in a second direction, which makes it easier to insert the electrode body into the case body.

[0011] (2) In the method for manufacturing an energy storage element described in (1) above, The electrode body includes a flat portion, In the flat portion, the electrodes may be stacked in the second direction.

[0012] According to the method for manufacturing a power storage element described in (2) above, the flat portion of the electrode body becomes thinner by compression, making it easier to insert the electrode body into the case body.

[0013] (3) In the method for manufacturing a power storage element described in (1) or (2) above, before the insertion of the electrode body, the electrode body may be further compressed in the second direction by the pressure of a gas.

[0014] According to the method for manufacturing a power storage element described in (3) above, pressure can be suitably applied to the entire surface of the electrode body.

[0015] (4) In the method for manufacturing a power storage element described in any one of (1) to (3) above, before the insertion of the electrode body, compressing the electrode body in a state where the electrode body is housed in a container, and sealing the container in a state where the electrode body is compressed, may be further provided, and the compressed state of the electrode body may be maintained by the sealing.

[0016] According to the method for manufacturing a power storage element described in (4) above, by sealing the container, the compressed state of the electrode body can be easily maintained.

[0017] (5) In the method for manufacturing a power storage element described in (4) above, the compression of the electrode body may be performed by evacuating the inside of the container.

[0018] According to the method for manufacturing a power storage element described in (5) above, the electrode body can be compressed by using the pressure from the surroundings applied to the container such as atmospheric pressure.

[0019] (6) In the method for manufacturing a power storage element described in (4) or (5) above, The procedure may further include releasing the seal after the insertion of the electrode body.

[0020] According to the method for manufacturing the energy storage element described in (6) above, access to the electrode body while it is inserted into the case body is made possible by releasing the seal on the housing.

[0021] Hereinafter, one embodiment of the present invention will be described with reference to Figures 1 to 8. Note that the names of each component (each element) in this embodiment are those of this embodiment and may differ from the names of each component (each element) in the background art.

[0022] First, the configuration of the energy storage element manufactured by the manufacturing method of this embodiment will be described below. Then, the manufacturing method of the energy storage element will be described.

[0023] Energy storage elements include primary batteries, secondary batteries, and capacitors. In this embodiment, a rechargeable secondary battery will be described as an example of an energy storage element. Note that the names of each component (each element) in this embodiment are specific to this embodiment and may differ from the names of each component (each element) in the background art.

[0024] The energy storage element in this embodiment is a non-aqueous electrolyte secondary battery. More specifically, the energy storage element is a lithium-ion secondary battery that utilizes electron transfer that occurs with the movement of lithium ions. This type of energy storage element supplies electrical energy. The energy storage element is used individually or in combination with other elements. Specifically, the energy storage element is used individually when the required output and voltage are small. On the other hand, when at least one of the required output and voltage is large, the energy storage element is used in combination with other energy storage elements in an energy storage device. In the energy storage device, the energy storage elements used in the device supply electrical energy.

[0025] Specifically, as shown in Figures 1 and 2, the energy storage element 1 comprises an electrode body 2 in which electrodes (positive electrode, negative electrode) are stacked, a case 3 that houses the electrode body 2, and terminals 4 that conduct electricity between the inside and outside of the case 3 and are exposed to the outside of the case 3. The energy storage element 1 also comprises a current collector 5 that electrically connects the electrode body 2 and the terminals 4. The energy storage element 1 of this embodiment includes an insulating member 6A that electrically insulates the electrode body 2 and the case 3. Note that in Figure 1, the insulating member 6A is not shown in order to make the configuration easier to understand.

[0026] Electrode body 2 is a so-called wound electrode body in which the electrodes are wound in a flattened shape. In this electrode body 2, the electrodes include a positive electrode and a negative electrode, and these positive and negative electrodes are stacked in a state where they are insulated from each other. In electrode body 2, the energy storage element 1 is charged and discharged by the movement of lithium ions between the positive and negative electrodes. In the following description, the direction in which the winding axis C of electrode body 2 extends (first direction) is defined as the X-axis direction in the Cartesian coordinate system, the minor axis direction of electrode body 2 (second direction perpendicular to the first direction) is defined as the Y-axis direction in the Cartesian coordinate system, and the major axis direction of electrode body 2 (third direction perpendicular to both the first and second directions) is defined as the Z-axis direction in the Cartesian coordinate system.

[0027] Specifically, as shown in Figure 3, the electrode body 2 has a flat portion 21 that extends in the Z-axis direction when viewed from the X-axis direction, and a pair of curved portions 22 that are positioned at both ends of the flat portion 21 in the Z-axis direction when viewed from the X-axis direction.

[0028] The flat portion 21 is a part of the electrode body 2 in which electrodes extending in a planar direction including the X-axis and Z-axis directions are stacked in the Y-axis direction.

[0029] The curved portion 22 is a region where electrodes, which are curved so as to be convex in the direction away from the flat portion 21 when viewed from the X-axis direction, are stacked in the Z-axis direction.

[0030] The positive electrode comprises a strip-shaped metal foil and a positive electrode active material layer superimposed on the metal foil. This positive electrode active material layer is superimposed on the metal foil with one edge (uncovered portion) in the width direction of the metal foil exposed. The metal foil in this embodiment is, for example, aluminum foil.

[0031] The negative electrode comprises a strip-shaped metal foil and a negative electrode active material layer superimposed on the metal foil. This negative electrode active material layer is superimposed on the metal foil with the other edge (uncoated portion) in the width direction of the metal foil (opposite the uncoated portion of the positive electrode metal foil) exposed. The metal foil in this embodiment is, for example, copper foil.

[0032] In the electrode body 2 of this embodiment, the positive electrode and the negative electrode are wound together in an insulated state by a separator. That is, in the electrode body 2 of this embodiment, the positive electrode, the negative electrode, and the separator are wound together in a stacked state.

[0033] The separator is an insulating component placed between the positive and negative electrodes. This insulates the positive and negative electrodes from each other in the electrode body 2. The separator also holds the electrolyte within the case 3. This allows lithium ions to move between the positive and negative electrodes, which are alternately stacked with the separator in between, during the charging and discharging of the energy storage element 1. This separator is strip-shaped and is made of a porous membrane such as polyethylene, polypropylene, cellulose, or polyamide.

[0034] The insulating member 6A electrically insulates the electrode body 2 from the case 3 by surrounding the electrode body 2 in the circumferential direction (the winding direction of the electrode). This insulating member 6A is formed of multiple sheet-like members 61 that are insulating and flexible (see Figures 5 and 6). These sheet-like members 61 are resistant to electrolyte. In this embodiment, the insulating member 6A is formed by cutting off (deleting) a part of a housing that is formed by sealing the peripheral edges of two sheet-like members 61 around its entire circumference.

[0035] The sheet-like member 61 in this embodiment is formed of polypropylene or the like, which has electrolyte resistance.

[0036] Case 3 is a rectangular parallelepiped or cubic shape of a size corresponding to the electrode body 2, and the electrode body 2 is housed such that the winding axis C of the electrode body 2 is aligned with the opposing direction (in this embodiment, the X-axis direction) of a pair of opposing wall portions (cover portions) 31, 32 in the rectangular parallelepiped or cubic shape.

[0037] Case 3 houses the electrolyte together with the electrode body 2 within its internal space. For this reason, Case 3 is made of a metal that is resistant to the electrolyte. In this embodiment, Case 3 is made of, for example, aluminum or an aluminum-based metal material such as an aluminum alloy.

[0038] Specifically, case 3 comprises a cylindrical case body 30 with openings at both ends in the X-axis direction, a first cover portion 31 that closes one opening (first opening) 30a of the case body 30 in the X-axis direction, and a second cover portion 32 that closes the other opening (second opening) 30b of the case body 30 in the X-axis direction (see Figure 2).

[0039] The case body 30 is rectangular in shape. More specifically, the case body 30 is a flattened rectangular tube. This case body 30 has a pair of long wall portions 301 that are spaced apart and facing each other in the Y-axis direction, and a pair of short wall portions 302 that are spaced apart and facing each other in the Z-axis direction. In the case body 30 of this embodiment, the first opening 30a and the second opening 30b have the same shape.

[0040] The elongated wall portion 301 is a part of the case body 30 that extends in a planar direction including the X-axis and Z-axis directions. In this embodiment, the elongated wall portion 301 is a rectangular shape that is elongated in the X-axis direction when viewed from the Y-axis direction.

[0041] The short wall portion 302 is a part of the case body 30 that extends in a planar direction including the X-axis and Y-axis directions. This short wall portion 302 connects to the edge of the long wall portion 301 in the Z-axis direction. In this embodiment, the short wall portion 302 is a rectangular shape that is elongated in the X-axis direction when viewed from the Z-axis direction. In this embodiment, the dimension of the short wall portion 302 in the Y-axis direction (circumferential direction of the case body 30) is smaller than the dimension of the long wall portion 301 in the Z-axis direction (circumferential direction of the case body 30).

[0042] The first cover portion 31 extends in a planar direction including the Y-axis and Z-axis directions, and has the same shape as the first opening 30a when viewed from the X-axis direction. In this embodiment, the first cover portion 31 is a rectangular plate-like member that is elongated in the Z-axis direction when viewed from the X-axis direction.

[0043] The second cover portion 32 extends in a planar direction including the Y-axis and Z-axis directions, and has the same shape as the second opening 30b when viewed from the X-axis direction. In this embodiment, the second cover portion 32 is a rectangular plate-like member that is elongated in the Z-axis direction when viewed from the X-axis direction. Furthermore, the second cover portion 32 in this embodiment has the same shape as the first cover portion 31.

[0044] Terminal 4 includes a first terminal 41 that is electrically connected to the positive electrode 2a of the electrode body 2, and a second terminal 42 that is electrically connected to the negative electrode 2b of the electrode body 2.

[0045] The first terminal 41 is a part that is electrically connected to the external terminals of other energy storage elements or to external equipment, etc. The first terminal 41 is arranged on the first cover portion 31 in a state of being electrically insulated from the first cover portion 31.

[0046] Specifically, the first terminal 41 has a first terminal body 411 that extends along the first cover portion 31, and a first through portion 412 that extends from the first terminal body 411 through the first cover portion 31 into the case 3 (see Figure 1).

[0047] The first terminal 41 is formed from a conductive material. This first terminal 41 is formed from a highly weldable metal material, such as aluminum or an aluminum alloy.

[0048] The second terminal 42 is a part that is electrically connected to the external terminals of other energy storage elements or to external devices, etc. The second terminal 42 is arranged on the second cover portion 32 in a state of being electrically insulated from the second cover portion 32.

[0049] Specifically, the second terminal 42 has a second terminal body 421 that extends along the second cover portion 32, and a second through portion 422 that extends from the second terminal body 421 through the second cover portion 32 into the case 3 (see Figure 1).

[0050] The second terminal 42 is formed from a conductive material. This second terminal 42 is formed from a highly weldable metal material, such as copper or a copper alloy.

[0051] The current collector 5 includes a first current collector 51 that electrically connects the positive electrode 2a of the electrode body 2 to the first terminal 41, and a second current collector 52 that electrically connects the negative electrode 2b of the electrode body 2 to the second terminal.

[0052] The first current collector 51 is formed of a conductive material and is electrically connected to the electrode body 2 and the first terminal 41. Specifically, the first current collector 51 is arranged along the inner surface of the case 3 (more specifically, the first cover portion 31) and is joined to the positive electrode 2a of the electrode body 2 and to the first through portion (the portion located inside the case 3) 412 of the first terminal 41. The first current collector 51 is formed of, for example, aluminum or an aluminum alloy.

[0053] The second current collector 52 is formed of a conductive material and electrically connects the electrode body 2 and the second terminal 42. Specifically, the second current collector 52 is positioned along the inner surface of the case 3 (more specifically, the second cover portion 32) and is joined to the negative electrode 2b of the electrode body 2 and to the second through portion (the portion located inside the case 3) 422 of the second terminal 42. The second current collector 52 is formed of, for example, copper or a copper alloy.

[0054] Next, the manufacturing method of the energy storage element 1 of this embodiment will be described with reference to Figures 4 to 7.

[0055] The prepared wound electrode body 2 is housed in the housing (later insulating member) 6 (step S1). Specifically, two sheet-like members 61 are stacked so that the electrode body 2 is sandwiched between them, and the peripheral edges of these two sheet-like members 61 are sealed (heat sealed, etc.) (see Figures 5 and 6). In this embodiment, the sheet-like members 61 are rectangular in shape and larger than the electrode body, and the sealing is performed along each side of the two stacked sheet-like members 61. This forms the housing 6 with the electrode body 2 housed inside. In Figures 6 to 8, the dotted areas 62 are the areas where the two sheet-like members 61 are sealed.

[0056] In this embodiment, when the electrode body 2 is housed in the housing 6, the peripheral edges of the two sheet-like members 61 are sealed (welded, etc.) to form a sealed portion 62, leaving a portion 62a used for exhausting the air inside the housing 6 (exhaust portion: a part of the peripheral edge) (see Figure 6).

[0057] Next, the electrode body 2 is compressed by exhausting the air from the housing 6 containing the electrode body 2 (step S2). This exhaust compresses the electrode body 2 due to the atmospheric pressure (gas pressure) applied to the housing 6. At this time, since the surface area of ​​the flat portion 21 of the electrode body 2 is larger than the surface area of ​​the curved portion 22, the electrode body 2 is compressed in the Y-axis direction (the stacking direction of the electrodes in the flat portion 21).

[0058] Once the exhaust from the housing 6 is complete, the housing 6 is sealed (step S3). That is, the exhaust area 62a is sealed at the periphery of the two sheet-like members 61.

[0059] Once the housing 6 is sealed, the electrode body 2 housed in the housing 6 is inserted into the case body 30 through the first opening 30a (step S4). At this time, the electrode body 2 is inserted into the case body 30 such that the direction in which the winding axis C of the electrode body 2 extends coincides with the direction connecting the first opening 30a and the second opening 30b of the case body 30. During this insertion of the electrode body 2 into the case body 30, the state in which the electrode body 2 is compressed in the Y-axis direction is maintained because the housing 6 is sealed after being evacuated.

[0060] Once the entire electrode body 2 housed in the housing 6 is inserted into the case body 30, the housing 6 is opened by cutting off its end (see Figures 7 and 8). In other words, the seal on the housing 6 is released (step S5). Here, releasing the seal is equivalent to returning from a reduced pressure state to a normal pressure state.

[0061] In the manufacturing method of the energy storage element 1 of this embodiment, both ends of the housing 6 in the X-axis direction are cut off. Specifically, at both ends of the housing 6 in the X-axis direction, the cut is made at a position closer to the center of the electrode body 2 than the seal portion 62 in the X-axis direction (see Figure 7). In this embodiment, perforations (see dashed lines in Figure 5) are provided at both ends of the two sheet-like members 61 constituting the housing 6 in the X-axis direction, and both ends of the housing 6 in the X-axis direction are cut along these perforations.

[0062] The housing 6, with both ends cut off, is used in the energy storage element 1 as an insulating member 6A that electrically insulates the electrode body 2 from the case body 30. Note that in Figures 7 and 8, the case 3 is not shown in order to make the configuration easier to understand.

[0063] When both ends of the housing 6 in the X-axis direction are opened (see Figure 8), the first terminal 41 and the second terminal 42 are electrically connected to each end of the electrode body in the X-axis direction (step S6). Specifically, at one end of the electrode body 2 in the X-axis direction, the positive electrode 2a of the electrode body 2 is electrically connected to the first terminal 41 via the first current collector 51, and at the other end of the electrode body 2 in the X-axis direction, the negative electrode 2b of the electrode body 2 is electrically connected to the second terminal 42 via the second current collector 52. At this time, the first terminal 41 is attached to the first cover portion 31, and the second terminal 42 is attached to the second cover portion 32.

[0064] Next, the first opening 30a of the case body 30 is closed with the first cover portion 31, and the second opening 30b of the case body 30 is closed with the second cover portion 32 (step S7). In this embodiment, the peripheral edge of the first cover portion 31 is welded to the first opening 30a, and the peripheral edge of the second cover portion 32 is welded to the second opening 30b.

[0065] When the respective cover parts 31 and 32 close the respective openings 30a and 30b of the case body 30 to form the case 3, electrolyte is poured into the case 3 through the injection holes provided in the case 3 (step S8). Once a predetermined amount of electrolyte has been poured, the injection holes are closed and the case 3 is sealed (step S9), thereby completing the energy storage element 1.

[0066] The above method for manufacturing the energy storage element 1 includes inserting an electrode body 2, on which electrodes are stacked, into a case body 30 having a first opening 31a in the X-axis direction (first direction) through the first opening, wherein the insertion of the electrode body 2 into the case body 30 is performed while the electrode body 2 is compressed in the Y-axis direction (second direction intersecting the first direction).

[0067] In this way, when inserting the electrode body 2 into the case body 30, the electrode body 2 is kept in a compressed state in the Y-axis direction, making it easier to insert the electrode body 2 into the case body 30.

[0068] In the manufacturing method of the energy storage element 1 of this embodiment, the electrode body 2 includes a flat portion 21, and in the flat portion 21, the electrodes are stacked in the Y-axis direction (second direction).

[0069] With this configuration, the flat portion 21 of the electrode body 2 becomes thinner due to compression, making it easier to insert the electrode body 2 into the case body 30.

[0070] The manufacturing method of the energy storage element 1 of this embodiment further includes compressing the electrode body 2 in the Y-axis direction (second direction) by gas pressure (atmospheric pressure in this example) before inserting the electrode body 2 into the case body 30. As a result, pressure is applied to the entire surface of the electrode body 2, and the electrode body 2 is compressed.

[0071] The manufacturing method of the energy storage element 1 of this embodiment further comprises compressing the electrode body 2 while it is housed in the housing 6 before inserting the electrode body 2 into the case body 30, and sealing the housing 6 while the electrode body 2 is compressed, so that the compressed state of the electrode body 2 is maintained by the sealing. In this way, the compressed state of the electrode body 2 can be easily maintained by sealing the housing 6.

[0072] In the manufacturing method of the energy storage element 1 of this embodiment, the electrode body 2 is compressed by exhausting the inside of the housing 6. With this configuration, the electrode body can be compressed by utilizing the ambient pressure applied to the housing, such as atmospheric pressure.

[0073] The manufacturing method of the energy storage element 1 of this embodiment further includes releasing the seal on the housing 6 after inserting the electrode body 2 into the case body 30. By releasing the seal on the housing 6 in this way, it becomes possible to access the electrode body 2 while it is inserted into the case body 30 (for example, to make electrical connections to the terminals 4).

[0074] It should be noted that the method for manufacturing the energy storage element of the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, the configuration of one embodiment can be added to the configuration of another embodiment, and a part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Furthermore, a part of the configuration of one embodiment can be deleted.

[0075] In the above embodiment, the X-axis direction (first direction), the Y-axis direction (second direction), and the Z-axis direction are orthogonal, but they do not have to be orthogonal. That is, the X-axis direction, the Y-axis direction, and the Z-axis direction only need to intersect.

[0076] In the manufacturing method of the energy storage element 1 of the above embodiment, the electrode body 2 has a flat portion 21, and electrodes are stacked in the Y-axis direction on the flat portion 21, but the method is not limited to this configuration. For example, the electrode body 2 may have a configuration without a flat portion 21, such as an electrode body 2 in which the electrodes are wound into a cylindrical shape. When the wound electrode body 2 is cylindrical, the entire circumferential surface of the electrode body 2 is compressed toward the central axis (winding axis). That is, the electrode body 2 should be compressed in a direction that makes it easy to insert the electrode body 2 into the case body 30 through the first opening 30a.

[0077] Furthermore, in the flat portion 21, the electrodes may be stacked in a direction other than the second direction (Y-axis direction).

[0078] In the stacking method of the energy storage element 1 in the above embodiment, the electrode body 2 is compressed in the Y-axis direction by the pressure of a gas (atmospheric pressure in the example of the above embodiment), but the configuration is not limited to this. The electrode body 2 may be compressed by the pressure of a gas other than atmospheric pressure. Alternatively, the electrode body 2 may be compressed by being sandwiched between two members. That is, the electrode body 2 may be compressed by the pressure of a solid.

[0079] In the manufacturing method of the energy storage element 1 of the above embodiment, the case body 30 has a first opening 30a and a second opening 30b, that is, it is cylindrical with two openings 30a and 30b, but it is not limited to this configuration. The case body 30 may have only the first opening 30a, that is, it may be box-shaped (bottomed cylindrical) with one opening 30a.

[0080] In the manufacturing method of the energy storage element 1 of the above embodiment, the electrode body 2 is a wound type formed by winding a long electrode, but is not limited to this configuration. The electrode body 2 may also be a stack type formed by stacking a plurality of plate-shaped electrodes, or a bellows type formed by folding a long electrode. In this case, the compression direction of the electrode body 2 when the electrode body 2 is inserted into the case body 30 is the direction in which the electrodes are stacked.

[0081] In the manufacturing method of the energy storage element 1 of the above embodiment, the electrode body 2 is inserted through the first opening 30a of the case body 30, but it may also be inserted through the second opening 30b.

[0082] In the manufacturing method of the energy storage element 1 of the above embodiment, the electrode body is compressed while housed in the housing, but the configuration is not limited to this. The electrode body 2 does not need to be housed in the housing 6 when it is inserted through the first opening 30a of the case body 30. That is, as long as the electrode body 2 is kept in a compressed state when it is inserted through the first opening 30a of the case body 30, the housing 6 is not necessary.

[0083] In the manufacturing method of the energy storage element 1 of the above embodiment, the electrode body 2 is compressed by atmospheric pressure by exhausting the air inside the housing 6, that is, by reducing the pressure inside the housing 6. However, the method is not limited to this configuration. The electrode body 2, while housed in the housing 6, may be placed in a container such as a chamber, and the electrode body 2 may be compressed by increasing the pressure around the housing 6 by supplying gas or liquid into the container, that is, by utilizing the pressure of the gas or liquid to compress the electrode body 2.

[0084] In the manufacturing method of the energy storage element 1 of the above embodiment, the housing 6 is opened (sealed) after the entire electrode body 2 is inserted into the case body 30, but the method is not limited to this configuration. The housing 6 may be opened when only a part of the electrode body 2 is inserted into the case body 30. Alternatively, the sealing of the housing 6 may be maintained even after the entire electrode body 2 is inserted into the case body 30. The housing 6 may be removed after the entire electrode body 2 is inserted into the case body 30. Here, "sealed" means that the sealing of the housing 6 is released to the extent that access to the electrodes is possible. In other words, the housing 6 does not have to be opened as shown in Figure 7. For example, the housing 6 around the electrode body 2a may be removed, or a hole may be made in a part of the housing 6.

[0085] In the manufacturing method of the energy storage element 1 of the above embodiment, the housing 6 houses one electrode body 2, but the configuration is not limited to this. The housing 6 may house multiple electrode bodies 2 (see Figure 9). In this case, the multiple electrode bodies 2 are housed in the housing 6 with the winding axes C of each electrode body 2 parallel to each other.

[0086] In the manufacturing method of the energy storage element 1 of the above embodiment, the insulating member 6A is formed by a plurality of sheet-like members 61, but the configuration is not limited to this. The insulating member 6A may be formed by a single sheet-like member 61. In this case, as shown in Figure 9, by folding a single sheet-like member 61 to form the insulating member 6A (housing body 6) such that a seal portion 62 is formed at one end in the Z-axis direction, the thickness in the Z-axis direction is reduced compared to the case where seal portions 62 are formed at both ends in the Z-axis direction. [Explanation of Symbols]

[0087] 1...Energy storage element, 2...Electrode body, 2a...Positive electrode of electrode body, 2b...Negative electrode of electrode body, 21...Flat section, 22...Curved section, 3...Case, 30...Case body, 30a...First opening, 30b...Second opening, 301...Long wall section, 302...Short wall section, 31...First cover section, 32...Second cover section, 4...Terminal, 41...First terminal, 411...First terminal body, 412...First through section, 42...Second terminal, 421...Second terminal body, 422...Second through section, 5...Current collector, 51...First current collector, 52...Second current collector, 6...Housing, 6A...Insulating member, 61...Sheet-like member, 62...Seal section, 62a...Exhaust section, C...Winding shaft

Claims

1. The device comprises inserting an electrode body, in which electrodes are stacked, into a case body having an opening in the first direction through the opening, A method for manufacturing an energy storage element, wherein the insertion of the electrode body is performed while maintaining a state in which the electrode body is compressed in a second direction intersecting the first direction.

2. The electrode body includes a flat portion, The method for manufacturing an energy storage element according to claim 1, wherein in the flat portion, the electrodes are stacked in the second direction.

3. A method for manufacturing an energy storage element according to claim 1 or 2, further comprising compressing the electrode body in the second direction by gas pressure before insertion of the electrode body.

4. Before inserting the electrode body, the electrode body is compressed while it is housed in the housing, The electrode body is further sealed in the housing while it is compressed, The method for manufacturing an energy storage element according to claim 1 or 2, wherein the compressed state of the electrode body is maintained by the sealing.

5. The method for manufacturing an energy storage element according to claim 4, wherein the compression of the electrode body is performed by exhausting the inside of the housing.

6. The method for manufacturing an energy storage element according to claim 4, further comprising releasing the seal after the insertion of the electrode body.

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