Electric energy storage device and method for manufacturing the same

Abstract

To provide a power storage device which can elastically compress an electrode laminate unit of an electrode body by the power storage device itself and can prevent an impregnated electrolyte in the electrode body from flowing to the outside of the electrode body.SOLUTION: A power storage device 1 has a case 10 including: a bottomed angular cylindrical body member 21 forming a second main wall part 12 and four side wall parts 13 to 16; and a rectangular lid member 31 forming a first main wall part 11, the first main wall part 11 and the second main wall part 12 elastically compressing an electrode laminate unit 50e of an electrode body 50. The case also includes: a center part pressing unit 41 for pressing a center part 50ea of the electrode laminate unit 50e; and a communicating part pressing unit 46 for pressing an external communicating part 50ebc of the electrode laminate unit 50e and restricting flowing-out of the impregnated electrolyte 3a from the electrode laminate unit 50e through the external communicating part 50ebc.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a rectangular power storage device in which an electrode body is housed in a rectangular parallelepiped box-shaped case, and a method for manufacturing the power storage device.

Background Art

[0002] Among rectangular batteries in which an electrode body is housed in a rectangular parallelepiped box-shaped case, particularly in batteries mounted on vehicles or the like and used over a long period of time, for reasons such as improving charge-discharge cycle characteristics, the battery is generally externally constrained using a constraint member outside the battery composed of a pair of end plates and a plurality of restraint bands. As a result, the electrode stacking portion of the electrode body housed in the case is pressed in the direction of the electrode body thickness. As a related prior art, for example, Patent Document 1 can be cited (see FIG. 1 etc. of Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when externally constraining the battery using a constraint member, there are problems such as increased cost, increased size, increased weight, and increased number of parts. Another problem is that, with the use of the battery, the impregnated electrolyte contained in the electrode body is pushed out of the electrode body, resulting in a decrease in the impregnated electrolyte that can contribute to charge and discharge. That is, the electrode body expands and contracts with charge and discharge. When the electrode body expands in the case, the impregnated electrolyte is pushed out of the electrode body, so that the electrolyte that can contribute to charge and discharge decreases, resulting in a decrease in battery capacity or an increase in battery resistance.

[0005] The present invention has been made in view of such a situation, and provides a power storage device that can elastically compress the electrode laminate of the electrode body in the electrode body thickness direction by the power storage device itself and suppress the outflow of the impregnated electrolyte in the electrode body to the outside of the electrode body during the use of the power storage device, and a method for manufacturing the power storage device.

Means for Solving the Problems

[0006] (1) One aspect of the present invention for solving the above problems includes a case, an electrode body housed in the case, and an impregnated electrolyte impregnated in the electrode body. The case is in the shape of a rectangular parallelepiped box, having a rectangular first main wall portion, a rectangular second main wall portion facing the first main wall portion, and four rectangular side wall portions extending in the case thickness direction and connecting between the first main wall portion and the second main wall portion. The electrode body includes electrode plates and has a rectangular parallelepiped-shaped electrode laminate portion in which the electrode plates are laminated in the electrode body thickness direction. The electrode body is housed in the case in a posture where the electrode body thickness direction is parallel to the case thickness direction. The electrode laminate portion has a central portion located inside in the laminate portion expansion direction orthogonal to the electrode body thickness direction, and an outer peripheral portion surrounding the central portion from the outside in the laminate portion expansion direction. The outer peripheral portion includes an external communication portion communicating with the outside of the electrode body. A power storage device, wherein the case includes a bottomed square tube-shaped main body member forming the second main wall portion and the four side wall portions, and having a rectangular opening formed by the four side wall portions, and a rectangular lid member forming the first main wall portion and having a lid peripheral portion joined to the entire periphery of the opening peripheral edge of the main body member. The first main wall portion and the second main wall portion of the case elastically compress the electrode laminate portion of the electrode body in the electrode body thickness direction. Due to the elastic compression by the first main wall portion and the second main wall portion, a central portion pressing portion that presses the central portion of the electrode laminate portion of the electrode body in the electrode body thickness direction, and due to the elastic compression by the first main wall portion and the second main wall portion, a communication portion pressing portion that presses the external communication portion of the electrode laminate portion of the electrode body in the electrode body thickness direction and restricts the outflow of the impregnated electrolyte to the outside of the electrode laminate portion through the external communication portion.

[0007] In the above-described power storage device, the first main wall portion and the second main wall portion of the case elastically compress the electrode stacking portion of the electrode body in the electrode body thickness direction. That is, this power storage device is a self-compression type that elastically compresses the electrode stacking portion of the electrode body by the power storage device itself. Therefore, when using the power storage device, it is not necessary to separately use a restraining member, or external restraint by a simple restraining member is sufficient. Furthermore, in the above-described power storage device, since the case is formed by joining a lid member forming the first main wall portion to a main body member forming the second main wall portion and the four side wall portions, as will be described later, a self-compression type power storage device can be easily manufactured, and an inexpensive power storage device can be obtained.

[0008] Also, the above-described power storage device has a central portion pressing portion that presses the central portion of the electrode stacking portion of the electrode body, and a communication portion pressing portion that presses the external communication portion of the outer peripheral portion of the electrode stacking portion of the electrode body to restrict the outflow of the impregnated electrolyte outside the electrode stacking portion. Therefore, the electrode stacking portion can be pressed over a wider range, and the outflow of the impregnated electrolyte outside the electrode stacking portion through the external communication portion can be suppressed. Thereby, it is possible to suppress a decrease in the performance of the power storage device during use.

[0009] Note that examples of the "power storage device" include secondary batteries such as lithium ion secondary batteries, capacitors such as lithium ion capacitors, and all-solid-state batteries. Also, the "external communication portion" is, for example, when the electrode body is a flat wound type in which a strip-shaped positive electrode plate and a strip-shaped negative electrode plate, which are electrode plates, are wound flatly via a pair of strip-shaped separators, both end portions in the electrode body axis direction of the outer peripheral portion of the electrode stacking portion are each an external communication portion. Also, when the electrode body is a stacked type in which a plurality of rectangular positive electrode plates and a plurality of rectangular negative electrode plates, which are electrode plates, are stacked via rectangular separators, the entire outer peripheral portion of the electrode stacking portion is an external communication portion.

[0010] The "central pressing part" and the "communication part pressing part" can be provided on at least one of the first main wall part and the second main wall part of the case. Specifically, the central pressing part and the communication part pressing part are respectively provided on both the first main wall part and the second main wall part, the central pressing part and the communication part pressing part are provided only on the first main wall part, the central pressing part and the communication part pressing part are provided only on the second main wall part, the central pressing part is provided on the first main wall part, the communication part pressing part is provided on the second main wall part, the communication part pressing part is provided on the first main wall part, and the central pressing part is provided on the second main wall part, etc.

[0011] Alternatively, the central pressing part and the communication part pressing part can also be separate members from the case. That is, an intervening member can be arranged between the first main wall part of the case and the electrode stacking part of the electrode body, or between the second main wall part of the case and the electrode stacking part of the electrode body, and the central pressing part or the communication part pressing part can be provided on this intervening member. Specifically, for example, an intervening member is arranged between the first main wall part and the electrode stacking part, and the central pressing part and the communication part pressing part are provided on this intervening member, or an intervening member is arranged between the second main wall part and the electrode stacking part, and the central pressing part and the communication part pressing part are provided on this intervening member. Also, a first intervening member is arranged between the first main wall part and the electrode stacking part, and a second intervening member is arranged between the second main wall part and the electrode stacking part. The central pressing part and the communication part pressing part are respectively provided on both the first intervening member and the second intervening member, or only the central pressing part is provided on one intervening member, and only the communication part pressing part is provided on the other intervening member, etc. Also, an intervening member is arranged between the first main wall part and the electrode stacking part, and only the central pressing part is provided on this intervening member, and only the communication part pressing part is provided on the second main wall part of the case, etc.

[0012] (2) Further, it is the power storage device described in (1), and an intervening member is provided between at least one of the first main wall part of the case and the electrode stacking part of the electrode body, and between the second main wall part of the case and the electrode stacking part of the electrode body. It is preferable that the communication part pressing part is provided on the intervening member to form a power storage device.

[0013] In the above-described power storage device, an intervening member is disposed between at least one of the first main wall portion of the case and the electrode stacking portion of the electrode body and between the second main wall portion of the case and the electrode stacking portion of the electrode body, and the above-described communication portion pressing portion is provided on this intervening member. Therefore, when disposing an intervening member having a communication portion pressing portion between the first main wall portion and the electrode stacking portion, it is not necessary to provide the communication portion pressing portion on the first main wall portion. Further, when disposing an intervening member having a communication portion pressing portion between the second main wall portion and the electrode stacking portion, it is not necessary to provide the communication portion pressing portion on the second main wall portion.

[0014] Note that the "intervening member" may be an intervening member in which only a part of the intervening member forms a communication portion pressing portion, or an intervening member in which the entire intervening member forms a communication portion pressing portion. Regarding the above-described central portion pressing portion, it may be provided on the first main wall portion or the second main wall portion of the case, or an intervening member may be disposed between the first main wall portion or the second main wall portion of the case and the electrode stacking portion of the electrode body, and the central portion pressing portion may be provided on this intervening member. Note that the intervening member provided with the central portion pressing portion and the intervening member provided with the communication portion pressing portion may be the same intervening member or different intervening members.

[0015] (3) Furthermore, the power storage device according to (1), wherein the communication portion pressing portion is provided on at least one of the first main wall portion and the second main wall portion of the case, is preferable.

[0016] In the above-described power storage device, the above-described communication portion pressing portion is provided on at least one of the first main wall portion and the second main wall portion of the case. Therefore, when providing the communication portion pressing portion on the first main wall portion, it is not necessary to dispose an intervening member having a communication portion pressing portion between the first main wall portion and the electrode stacking portion. Further, when providing the communication portion pressing portion on the second main wall portion, it is not necessary to dispose an intervening member having a communication portion pressing portion between the second main wall portion and the electrode stacking portion.

[0017] Regarding the aforementioned central pressing portion, it may be provided on the first main wall portion or the second main wall portion of the case, or an intervening member may be disposed between the first main wall portion or the second main wall portion of the case and the electrode stacking portion of the electrode body, and the central pressing portion may be provided on this intervening member.

[0018] (4) Furthermore, it is a power storage device according to any one of (1) to (3), and an intervening member is provided between at least one of the first main wall portion of the case and the electrode stacking portion of the electrode body and between the second main wall portion of the case and the electrode stacking portion of the electrode body, and it is preferable that the central pressing portion is provided on the intervening member to form a power storage device.

[0019] In the above-mentioned power storage device, an intervening member is disposed between at least one of the first main wall portion of the case and the electrode stacking portion of the electrode body and between the second main wall portion of the case and the electrode stacking portion of the electrode body, and the aforementioned central pressing portion is provided on this intervening member. Therefore, when disposing an intervening member having a central pressing portion between the first main wall portion and the electrode stacking portion, it is not necessary to provide the central pressing portion on the first main wall portion. Also, when disposing an intervening member having a central pressing portion between the second main wall portion and the electrode stacking portion, it is not necessary to provide the central pressing portion on the second main wall portion.

[0020] Note that the "intervening member" may be an intervening member in which only a part of the intervening member forms the central pressing portion, or an intervening member in which the entire intervening member forms the central pressing portion.

[0021] (5) Furthermore, it is a power storage device according to any one of (1) to (3), and it is preferable that the central pressing portion is provided on at least one of the first main wall portion and the second main wall portion of the case to form a power storage device.

[0022] In the above-described power storage device, the aforementioned central pressing portion is provided on at least one of the first main wall portion and the second main wall portion of the case. Therefore, when the central pressing portion is provided on the first main wall portion, there is no need to dispose an intervening member having the central pressing portion between the first main wall portion and the electrode laminate. Further, when the communication portion pressing portion is provided on the second main wall portion, there is no need to dispose an intervening member having the central pressing portion between the second main wall portion and the electrode laminate.

[0023] (6) Another aspect includes a case, an electrode body housed within the case, and an impregnated electrolytic solution impregnated within the electrode body. The case has a rectangular parallelepiped box shape and includes a rectangular first main wall portion, a rectangular second main wall portion facing the first main wall portion, and four rectangular side wall portions that connect between the first main wall portion and the second main wall portion and extend in the case thickness direction. The electrode body includes an electrode plate and has a rectangular parallelepiped-shaped electrode stack portion in which the electrode plates are stacked in the electrode body thickness direction. The electrode body thickness direction is parallel to the case thickness direction and the electrode stack portion is housed within the case in this posture. The electrode stack portion has a central portion located inside in the stack portion spreading direction orthogonal to the electrode body thickness direction and an outer peripheral portion that surrounds the central portion from the outside in the stack portion spreading direction. The outer peripheral portion includes an external communication portion that communicates with the outside of the electrode body. The case includes a bottomed rectangular tubular body member that forms the second main wall portion and the four side wall portions and has a rectangular opening formed by the four side wall portions, and a rectangular lid member that forms the first main wall portion and has a lid peripheral portion joined to the entire opening peripheral edge of the opening of the body member. The first main wall portion and the second main wall portion of the case elastically compress the electrode stack portion of the electrode body in the electrode body thickness direction. Due to the elastic compression by the first main wall portion and the second main wall portion, there is a central portion pressing portion that presses the central portion of the electrode stack portion of the electrode body in the electrode body thickness direction, and due to the elastic compression by the first main wall portion and the second main wall portion, there is a communication portion pressing portion that presses the external communication portion of the electrode stack portion of the electrode body in the electrode body thickness direction and restricts the outflow of the impregnated electrolytic solution outside the electrode stack portion through the external communication portion. A method for manufacturing a power storage device includes a housing step of housing the electrode body within the body member, a pressing and compressing step of applying an external force to the first main wall portion formed by the lid member and the second main wall portion of the body member to press and compress the electrode stack portion of the electrode body in the electrode body thickness direction, a joining step of joining the lid peripheral portion of the lid member to the entire opening peripheral edge of the opening of the body member in the state where the electrode body is pressed and compressed to form the case, and a releasing step of releasing the external force after the joining step.

[0024] In a conventional rectangular battery, a case is constituted by a bottomed rectangular tubular body member forming a first main wall portion, a second main wall portion, and three side wall portions of the case, and a lid member forming one side wall portion. In a battery of such a form, it is difficult to manufacture a self-compression type battery. The gap between the first main wall portion and the second main wall portion of the body member is made narrower than the thickness of the electrode body, or in the case of a battery having the above-described intervening member, the combined thickness of the electrode body and the intervening member, in order to press and compress the electrode lamination portion of the electrode body in the assembled battery. Therefore, it is difficult to insert the electrode body and the like into the body member.

[0025] On the other hand, in the method for manufacturing the above-described power storage device, in the accommodation step, first, the electrode body is accommodated in a bottomed rectangular tubular body member forming a second main wall portion and four side wall portions. Therefore, the electrode body can be easily accommodated in the body member. Then, by performing the above-described pressing and compressing step, joining step, and releasing step, a self-compression type power storage device in which the electrode lamination portion of the electrode body is elastically compressed by the power storage device itself can be easily manufactured.

[0026] In addition, as a method for joining the lid member to the body member in the "joining step", for example, joining by welding such as laser welding, joining by caulking, and the like can be mentioned.

[0027] (7) Furthermore, it is a method for manufacturing the power storage device according to (6), wherein the power storage device includes an intervening member forming the communication portion pressing portion between at least one of the first main wall portion of the case and the electrode lamination portion of the electrode body, and between the second main wall portion of the case and the electrode lamination portion of the electrode body, and the accommodation step includes accommodating the electrode body and the intervening member with the intervening member stacked on the electrode body, and the pressing and compressing step presses the electrode body and the intervening member in the thickness direction of the electrode body. It is preferable to adopt a method for manufacturing a power storage device.

[0028] In the method for manufacturing the above-described power storage device, since the above-described intervening member is used to manufacture the power storage device, a power storage device in which the external communication portion of the electrode lamination portion of the electrode body is appropriately pressed by the communication portion pressing portion of the intervening member can be manufactured.

[0029] (8) Further, it is a method for manufacturing the power storage device according to (6), wherein the communication part pressing part is provided on at least one of the first main wall part and the second main wall part of the case, and the pressing and compressing step is preferably a method for manufacturing a power storage device in which the external communication part of the electrode body is pressed in the thickness direction of the electrode body by the communication part pressing part provided on the case.

[0030] In the above-described method for manufacturing a power storage device, by not arranging the intervening member forming the communication part pressing part, the housing step and the pressing and compressing step can be easily performed.

[0031] (9) Further, it is a method for manufacturing the power storage device according to any one of (5) to (8), wherein the power storage device includes an intervening member forming the central part pressing part between at least one of the first main wall part of the case and the electrode stacking part of the electrode body and between the second main wall part of the case and the electrode stacking part of the electrode body, the housing step is to house the electrode body and the intervening member with the intervening member stacked on the electrode body, and the pressing and compressing step is preferably a method for manufacturing a power storage device in which the electrode body and the intervening member are pressed in the thickness direction of the electrode body.

[0032] In the above-described method for manufacturing a power storage device, since the power storage device is manufactured using the above-described intervening member, a power storage device in which the central part of the electrode stacking part of the electrode body is appropriately pressed by the central part pressing part of the intervening member can be manufactured.

[0033] (10) Further, it is a method for manufacturing the power storage device according to any one of (5) to (8), wherein the central part pressing part is provided on at least one of the first main wall part and the second main wall part of the case, and the pressing and compressing step is preferably a method for manufacturing a power storage device in which the central part of the electrode body is pressed in the thickness direction of the electrode body by the central part pressing part provided on the case.

[0034] In the method for manufacturing the above-described power storage device, by not arranging the intervening member forming the central pressing portion, the accommodation step and the pressing and compressing step can be easily performed.

Brief Description of the Drawings

[0035]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

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Figure 15

Figure 16

Figure 17

Figure 18

Modes for Carrying Out the Invention

[0036] (Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a perspective view of a battery (power storage device) 1 according to Embodiment 1 of the present invention, FIG. 2 shows an exploded perspective view of the battery 1, and FIG. 3 shows a cross-sectional view of the battery 1. Further, FIG. 4 shows a plan view of the battery 1 as seen from the inner side CH3 in the thickness direction of the first intervening member 40, and FIG. 5 shows a plan view of the battery 1 as seen from the inner side CH3 in the thickness direction of the second intervening member 45. FIG. 6 shows a perspective view of the electrode body 50. In the following, the case height direction AH, the case width direction BH, the case thickness direction CH, the electrode body axis direction DH, the electrode body width direction EH, and the electrode body thickness direction FH are defined as the directions shown in FIGS. 1 to 6 for explanation. This battery 1 is a rectangular (cuboid-shaped) sealed lithium-ion secondary battery mounted on vehicles such as hybrid cars, plug-in hybrid cars, and electric vehicles.

[0037] The battery 1 is composed of a case 10, a flat wound electrode body 50 housed in the case 10, a positive electrode terminal 60 and a negative electrode terminal 70 respectively supported by the case 10, etc. The electrode body 50 is covered in the case 10 by a bag-shaped insulating holder (not shown) made of an insulating film. Also, in the case 10, a first intervening member 40 and a second intervening member 45 are housed so as to overlap the electrode body 50 (see FIGS. 2 to 5, not shown in FIG. 1). Further, an electrolytic solution 3 is housed in the case 10, a part of which is impregnated as an impregnated electrolytic solution 3a in the electrode body 50, and the rest accumulates on the second side wall portion 14 which is the lower wall portion of the case 10.

[0038] Among these, the case 10 is made of metal (aluminum in the present Embodiment 1). This case 10 is in the shape of a rectangular parallelepiped box and has a first main wall portion 11, a second main wall portion 12, and four side wall portions 13 to 16 (a first side wall portion 13, a second side wall portion 14, a third side wall portion 15, and a fourth side wall portion 16), each of which is in the shape of a rectangular plate. The first main wall portion 11 and the second main wall portion 12 are larger in area than the side wall portions 13 to 16. The first main wall portion 11 and the second main wall portion 12 face each other, the first main wall portion 11 is on one side CH1 of the case thickness direction CH (the front right side in FIGS. 1 and 2, the upper side in FIG. 3), and the second main wall portion 12 is on the other side CH2 of the case thickness direction CH (the back left side in FIGS. 1 and 2, the lower side in FIG. 3).

[0039] On the other hand, the side wall portions 13 to 16 connect between the first main wall portion 11 and the second main wall portion 12 and extend in the case thickness direction CH respectively. The first side wall portion 13 and the second side wall portion 14 face each other, the first side wall portion 13 is on the upper side AH1 of the case height direction AH, and the second side wall portion 14 is on the lower side AH2 of the case height direction AH. Also, the third side wall portion 15 and the fourth side wall portion 16 face each other, the third side wall portion 15 is on one side BH1 of the case width direction BH, and the fourth side wall portion 16 is on the other side BH2 of the case width direction BH.

[0040] On the first side wall portion 13, which is also the upper wall portion of the case 10, a safety valve 17 is provided which breaks and opens when the internal pressure of the case 10 exceeds the opening pressure. Further, on the first side wall portion 13, a liquid injection hole 13k for communicating the inside and outside of the case 10 is provided, and is airtightly sealed with a disc-shaped sealing member 18 made of aluminum. Furthermore, in the first side wall portion 13, near the end of one side BH1 in the case width direction BH, a positive electrode terminal 60 is fixedly provided. Specifically, the positive electrode terminal 60 is formed by clamping and connecting a plurality of metal members made of aluminum, and is fixedly provided on the first side wall portion 13 in a state of being insulated from the first side wall portion 13 via a resin portion 65 made of a plurality of resin members. This positive electrode terminal 60 is connected and conducts to the positive electrode current collecting portion 50c of the electrode body 50 inside the case 10, while extending through the first side wall portion 13 to the outside of the battery.

[0041] Also, in the first side wall portion 13, near the end of the other side BH2 in the case width direction BH, a negative electrode terminal 70 is fixedly provided. Specifically, the negative electrode terminal 70 is formed by clamping and connecting a plurality of metal members made of copper, and is fixedly provided on the first side wall portion 13 in a state of being insulated from the first side wall portion 13 via a resin portion 75 made of a plurality of resin members. This negative electrode terminal 70 is connected and conducts to the negative electrode current collecting portion 50d of the electrode body 50 inside the case 10, while extending through the first side wall portion 13 to the outside of the battery.

[0042] The case 10 is composed of a bottomed rectangular tube-shaped main body member 21 having a rectangular opening 21c, and a rectangular plate-shaped lid member 31. Among these, the main body member 21 forms the aforementioned second main wall portion 12 and four side wall portions 13 to 16, and the opening 21c of the main body member 21 is composed of the four side wall portions 13 to 16. On the other hand, the lid member 31 forms the aforementioned first main wall portion 11 and closes the opening 21c of the main body member 21. Specifically, the lid peripheral edge portion 31f of the lid member 31 is joined (welded) to the opening peripheral edge portion 21f of the opening 21c of the main body member 21 over the entire circumference.

[0043] Next, the electrode body 50 will be described (see FIGS. 1 to 3 and FIG. 6). This electrode body 50 is formed by overlapping a strip-shaped positive electrode plate (electrode plate) 51 and a strip-shaped negative electrode plate (electrode plate) 54 with each other via a pair of separators 57 made of a strip-shaped resin porous film, winding them cylindrically around the winding axis DX, and then pressing them flat. That is, the electrode body 50 has a pair of electrode R portions 50r respectively located at both ends in the electrode body width direction EH, and an electrode stacking portion 50e located between them. The electrode R portion 50r is a portion where the positive electrode plate 51, the negative electrode plate 54, and the separator 57 overlap while being bent in a semi-cylindrical shape. On the other hand, the electrode stacking portion 50e is a rectangular parallelepiped-shaped portion where the positive electrode plate 51, the negative electrode plate 54, and the separator 57 are stacked in a flat plate shape in the electrode body thickness direction FH. Furthermore, the electrode body 50 has a positive electrode current collector portion 50c, which will be described later, at one end DH1 in the electrode body axis direction DH along the winding axis DX, and a negative electrode current collector portion 50d, which will be described later, at the other end DH2 in the electrode body axis direction DH.

[0044] The electrode stacking portion 50e of the electrode body 50 has a rectangular parallelepiped-shaped central portion 50ea located inside GH1 in the stacking portion expansion direction GH orthogonal to the electrode body thickness direction FH, and a rectangular annular outer peripheral portion 50eb surrounding the central portion 50ea from the outside GH2 in the stacking portion expansion direction GH. Among the outer peripheral portion 50eb of the electrode stacking portion 50e, the portions located at both ends in the electrode body width direction EH and extending in the electrode body axis direction DH do not communicate with the outside of the electrode body 50 because the electrode R portion 50r exists outside them.

[0045] On the other hand, among the outer peripheral portion 50eb of the electrode stacking portion 50e, the portions located at both ends in the electrode body axis direction DH and extending in the electrode body width direction EH are external communication portions 50ebc that communicate with the outside of the electrode body 50 through the positive electrode current collector portion 50c or the negative electrode current collector portion 50d, respectively. Therefore, in the first embodiment 1, as the impregnated electrolyte 3a in the electrode stacking portion 50e moves as indicated by the arrow P in FIG. 6 with the use of the battery 1, it flows out of the electrode body 50 through the positive electrode current collector portion 50c or the negative electrode current collector portion 50d from the external communication portion 50ebc of the outer peripheral portion 50eb.

[0046] The electrode body 50 is accommodated in the case 10 in a posture where the electrode body axis direction DH is parallel to the case width direction BH, the electrode body width direction EH is parallel to the case height direction AH, and the electrode body thickness direction FH is parallel to the case thickness direction CH. Further, the electrode body 50 is accommodated in the case 10 in a state where the electrode laminate portion 50e is compressed in the electrode body thickness direction FH (case thickness direction CH). That is, the battery 1 is a self-compressing type battery, the case 10 is elastically deformed, and the first main wall portion 11 and the second main wall portion 12 of the case 10 elastically compress the electrode laminate portion 50e of the electrode body 50 in the electrode body thickness direction FH.

[0047] The positive electrode plate 51 has a positive electrode current collector foil 52 made of a strip-shaped aluminum foil. On both main surfaces of this positive electrode current collector foil 52, positive electrode active material layers 53 each containing positive electrode active material particles capable of occluding and releasing lithium ions are formed in a strip shape. Among the positive electrode plates 51, one end in the width direction has no positive electrode active material layer 53 on the positive electrode current collector foil 52, and the positive electrode current collector foil 52 is exposed. The exposed portion of this positive electrode current collector foil 52 protrudes in a spiral shape from the electrode laminate portion 50e to one side DH1 in the electrode body axis direction DH in the electrode body 50, forming the aforementioned positive electrode current collecting portion 50c. The positive electrode current collecting portion 50c is connected to the positive electrode terminal 60.

[0048] The negative electrode plate 54 has a negative electrode current collector foil 55 made of a strip-shaped copper foil. On both main surfaces of this negative electrode current collector foil 55, negative electrode active material layers 56 each containing negative electrode active material particles capable of occluding and releasing lithium ions are formed in a strip shape. Among the negative electrode plates 54, one end in the width direction has no negative electrode active material layer 56 on the negative electrode current collector foil 55, and the negative electrode current collector foil 55 is exposed. The exposed portion of this negative electrode current collector foil 55 protrudes in a spiral shape from the electrode laminate portion 50e to the other side DH2 in the electrode body axis direction DH in the electrode body 50, forming the aforementioned negative electrode current collecting portion 50d. The negative electrode current collecting portion 50d is connected to the negative electrode terminal 70.

[0049] Next, the first intermediate member 40 and the second intermediate member 45 will be described (see FIGS. 4, 5, 3, and 2; the pressing portion is not shown in FIG. 2). The first intermediate member 40 and the second intermediate member 45 are made of metal (aluminum in the first embodiment 1) and are rectangular in plan view. The first intermediate member 40 is interposed between the first main wall portion 11 of the case 10 and the electrode laminate portion 50e of the electrode body 50, and the second intermediate member 45 is interposed between the second main wall portion 12 of the case 10 and the electrode laminate portion 50e of the electrode body 50.

[0050] Among these, the first intermediate member 40 includes a rectangular central pressing portion 41 that forms the central portion of the first intermediate member 40, and a rectangular annular plate-shaped base portion 42 that is located outside the central pressing portion 41 and forms the outer peripheral portion of the first intermediate member 40. The central pressing portion 41 protrudes toward the inner side CH3 in the thickness direction in the case thickness direction CH (toward the electrode laminate portion 50e of the electrode body 50) from the base portion 42, and by the elastic compression by the first main wall portion 11 and the second main wall portion 12 of the case 10, the central portion 50ea of the electrode laminate portion 50e of the electrode body 50 is pressed in the electrode body thickness direction FH.

[0051] On the other hand, the second intermediate member 45 includes two communication portion pressing portions 46 and a base portion 47. The communication portion pressing portions 46 are each rectangular and extend in the case height direction AH near both ends in the case width direction BH. The base portion 47 is plate-shaped and forms a portion of the second intermediate member 45 other than the communication portion pressing portions 46. The communication portion pressing portions 46 each protrude toward the inner side CH3 in the thickness direction in the case thickness direction CH (toward the electrode laminate portion 50e of the electrode body 50) from the base portion 47, and by the elastic compression by the first main wall portion 11 and the second main wall portion 12 of the case 10, the external communication portion 50ebc of the outer peripheral portion 50eb of the electrode laminate portion 50e of the electrode body 50 is pressed in the electrode body thickness direction FH.

[0052] As shown by the arrow P indicating the movement of the impregnated electrolytic solution 3a in FIG. 5, the impregnated electrolytic solution 3a within the electrode laminate portion 50e moves respectively to one side BH1 and the other side BH2 in the case width direction BH (one side DH1 and the other side DH2 in the electrode body axis direction DH), and attempts to flow out of the electrode laminate portion 50e through the external communication portion 50ebc of the electrode laminate portion 50e. In contrast, by the communication portion pressing portion 46 of the second intervening member 45 pressing the external communication portion 50ebc of the electrode laminate portion 50e respectively, the outflow of the impregnated electrolytic solution 3a through the external communication portion 50ebc to the outside of the electrode laminate portion 50e is restricted.

[0053] In the battery 1 of the first embodiment, the first main wall portion 11 and the second main wall portion 12 of the case 10 elastically compress the electrode laminate portion 50e of the electrode body 50 in the electrode body thickness direction FH. That is, this battery 1 is a self-compression type that elastically compresses the electrode laminate portion 50e of the electrode body 50 by the battery 1 itself. For this reason, when using the battery 1, it is not necessary to separately use a restraining member, or external restraint by a simple restraining member is sufficient. Furthermore, since the case 10 of the battery 1 is formed by joining the lid member 31 forming the first main wall portion 11 to the main body member 21 forming the second main wall portion 12 and the four side wall portions 13 to 16, as will be described later, the self-compression type battery 1 can be easily manufactured, and an inexpensive battery 1 can be obtained.

[0054] The battery 1 also has a central portion pressing portion 41 that presses the central portion 50ea of the electrode laminate portion 50e of the electrode body 50, and a communication portion pressing portion 46 that presses the external communication portion 50ebc of the outer peripheral portion 50eb of the electrode laminate portion 50e of the electrode body 50 to restrict the outflow of the impregnated electrolytic solution 3a to the outside of the electrode laminate portion 50e. For this reason, the electrode laminate portion 50e can be pressed over a wider range, and the outflow of the impregnated electrolytic solution 3a through the external communication portion 50ebc to the outside of the electrode laminate portion 50e can be suppressed. Thereby, it is possible to suppress the deterioration of the performance of the battery 1 as the battery 1 is used.

[0055] Furthermore, in the first embodiment, a second intervening member 45 is disposed between the second main wall portion 12 of the case 10 and the electrode stacking portion 50e of the electrode body 50, and a communication portion pressing portion 46 is provided on the second intervening member 45. Therefore, it is not necessary to provide a communication portion pressing portion on the second main wall portion 12 of the case 10. Also, a first intervening member 40 is disposed between the first main wall portion 11 of the case 10 and the electrode stacking portion 50e of the electrode body 50, and a central portion pressing portion 41 is provided on the first intervening member 40. Therefore, it is not necessary to provide a central portion pressing portion on the first main wall portion 11 of the case 10.

[0056] Next, a method for manufacturing the battery 1 will be described (see FIGS. 7 to 10). In advance, a main body member 21 with a positive electrode terminal 60 and a negative electrode terminal 70 fixed thereto and a lid member 31 are prepared. Also, a strip-shaped positive electrode plate 51, a negative electrode plate 54, and a pair of separators 57 are wound cylindrically around a winding axis DX and then pressed flat to form an electrode body 50. Further, this electrode body 50 is wrapped with a bag-shaped insulating holder (not shown).

[0057] Then, in the "accommodation step S1" (see FIG. 7), the electrode body 50 wrapped with the insulating holder, the first intervening member 40, and the second intervening member 45 are accommodated in the main body member 21 with the positive electrode terminal 60 and the negative electrode terminal 70 fixed thereto, and the first intervening member 40 and the second intervening member 45 are stacked on the electrode body 50 for accommodation (see FIG. 8). Specifically, the main body member 21 is placed on the flat mounting table 510 of the pressing device 500 in a posture where the entire second main wall portion 12 thereof is in contact with the mounting table 510. Then, first, the second intervening member 45 is accommodated in the main body member 21, and further, the electrode body 50 is accommodated in a posture where the electrode body axis direction DH is parallel to the case width direction BH, the electrode body width direction EH is parallel to the case height direction AH, and the electrode body thickness direction FH is parallel to the case thickness direction CH, and the electrode stacking portion 50e of the electrode body 50 is stacked on the second intervening member 45. Subsequently, the first intervening member 40 is stacked on the electrode stacking portion 50e of this electrode body 50. Then, the positive electrode current collecting portion 50c of the electrode body 50 and the positive electrode terminal 60 fixed to the main body member 21 are connected by laser welding. Also, the negative electrode current collecting portion 50d of the electrode body 50 and the negative electrode terminal 70 fixed to the main body member 21 are connected by laser welding.

[0058] Next, in the "pressing and compressing step S2" (see FIG. 7), the lid member 31 is placed on the second intervening member 45, the electrode body 50, and the first intervening member 40 housed in the main body member 21, and an external force Fa is applied to the first main wall portion 11 formed by the lid member 31 and the second main wall portion 12 of the main body member 21 to press the second intervening member 45, the electrode laminate portion 50e of the electrode body 50, and the first intervening member 40 in the electrode body thickness direction FH and compress the electrode laminate portion 50e (see FIG. 9). Specifically, the pressing portion 520 of the pressing device 500 is brought into contact with the first main wall portion 11 formed by the lid member 31, and the lid member 31 and the main body member 21 are sandwiched between the pressing portion 520 and the mounting table 510 to apply an external force Fa to the first main wall portion 11 and the second main wall portion 12. Then, the second intervening member 45, the electrode laminate portion 50e of the electrode body 50, and the first intervening member 40 are pressed in the electrode body thickness direction FH, the electrode laminate portion 50e is compressed, and the lid peripheral portion 31f of the lid member 31 is brought into contact with the opening peripheral portion 21f of the opening 21c of the main body member 21 over the entire circumference (see FIG. 10).

[0059] Next, in the "joining step S3" (see FIG. 7), with the electrode body 50 being pressed and compressed by the pressing device 500, the lid peripheral portion 31f of the lid member 31 is joined to the opening peripheral portion 21f of the main body member 21 over the entire circumference to form the case 10 (see FIG. 10). In the first embodiment, the lid peripheral portion 31f and the opening peripheral portion 21f are irradiated with laser light LB to perform laser welding, thereby joining the lid peripheral portion 31f and the opening peripheral portion 21f over the entire circumference.

[0060] Next, in the "releasing step S4" (see FIG. 7), the aforementioned external force Fa is released. That is, the pressing portion 520 of the pressing device 500 is moved away from the lid member 31 to release the external force Fa. At this time, since the case 10 has already been formed in the joining step S3, the compressed electrode laminate portion 50e does not return to its original state (thickness). After the external force Fa is released, the electrode laminate portion 50e is elastically compressed between the first main wall portion 11 and the second main wall portion 12 of the case 10.

[0061] Next, in the "electrolyte injection and sealing process S5", the electrolyte 3 is injected into the case 10 through the injection hole 13k, and the electrolyte 3 is impregnated into the electrode body 50. Then, the injection hole 13k is covered with the sealing member 18 from the outside, and the sealing member 18 is laser welded to the case 10 to hermetically seal the space between the sealing member 18 and the case 10. Next, in the "first charge and aging process S6", a charging device (not shown) is connected to this battery 1 to perform the first charge on the battery 1. Then, the initially charged battery 1 is left standing for a predetermined time to age the battery 1. Thus, the battery 1 is completed.

[0062] Here, in a conventional rectangular battery, the case 10 is composed of a bottomed rectangular tubular main body member forming the first main wall portion 11, the second main wall portion 12, and the three side wall portions (the second side wall portion 14, the third side wall portion 15, and the fourth side wall portion 16) of the case 10, and a lid member forming the first side wall portion 13. In a battery of such a form, it is difficult to manufacture a self-compression type battery. The gap between the first main wall portion 11 and the second main wall portion 12 of the main body member is made narrower than the combined thickness of the electrode body 50, the first intervening member 40, and the second intervening member 45 in order to press and compress the electrode stacking portion 50e of the electrode body 50 in the assembled battery. Therefore, it is difficult to insert the electrode body 50, the first intervening member 40, and the second intervening member 45 into the main body member.

[0063] On the other hand, in the manufacturing method of the battery 1 described above, in the accommodation process S1, the electrode body 50, the first intervening member 40, and the second intervening member 45 are accommodated in the bottomed rectangular tubular main body member 21 forming the second main wall portion 12 and the four side wall portions 13 to 16. Therefore, the electrode body 50, the first intervening member 40, and the second intervening member 45 can be easily accommodated in the main body member 21. Then, by performing the pressing and compression process S2, the joining process S3, and the releasing process S4, a self-compression type battery 1 in which the electrode stacking portion 50e of the electrode body 50 is elastically compressed by the battery 1 itself can be easily manufactured.

[0064] Furthermore, in the first embodiment, since the battery 1 is manufactured using the second intervening member 45, a battery 1 can be manufactured in which the external communication portion 50ebc of the electrode stacking portion 50e of the electrode body 50 is appropriately pressed by the communication portion pressing portion 46 of the second intervening member 45. Also, since the battery 1 is manufactured using the first intervening member 40, a battery 1 can be manufactured in which the central portion 50ea of the electrode stacking portion 50e of the electrode body 50 is appropriately pressed by the central portion pressing portion 41 of the first intervening member 40.

[0065] (Embodiment 2) Next, a second embodiment will be described (see FIGS. 11 to 13). Note that descriptions of parts similar to those in the first embodiment will be omitted or simplified. In the battery 1 of the first embodiment, the first intervening member 40 is disposed between the first main wall portion 11 of the case 10 and the electrode stacking portion 50e of the electrode body 50, and the second intervening member 45 is disposed between the second main wall portion 12 of the case 10 and the electrode stacking portion 50e of the electrode body 50. In contrast, in the battery (power storage device) 100 of the second embodiment, no intervening member is disposed between the first main wall portion 111 and the second main wall portion 112 of the case 110 and the electrode stacking portion 50e of the electrode body 50. On the other hand, in the second embodiment, the form of the case 110 is different from that of the case 10 of the first embodiment. A central portion pressing portion 141 is provided on the first main wall portion 111 of the case 110, and a communication portion pressing portion 146 is provided on the second main wall portion 112 of the case 110.

[0066] Specifically, the first main wall portion 111 of the case 110 of the second embodiment has a rectangular central portion pressing portion 141 at the central portion of the first main wall portion 111. This central portion pressing portion 141 protrudes toward the inner side CH3 in the thickness direction in the case thickness direction CH (toward the electrode stacking portion 50e of the electrode body 50), and presses the central portion 50ea of the electrode stacking portion 50e of the electrode body 50 in the electrode body thickness direction FH by elastic compression by the first main wall portion 111 and the second main wall portion 112 of the case 110.

[0067] On one hand, the second main wall portion 112 of the case 110 has rectangular communication portion pressing portions 146 extending in the case height direction AH near both ends in the case width direction BH. The communication portion pressing portions 146 each project toward the inner side CH3 in the thickness direction in the case thickness direction CH (toward the electrode stacking portion 50e of the electrode body 50), and by the elastic compression by the first main wall portion 111 and the second main wall portion 112 of the case 110, the outer peripheral portion 50eb of the electrode stacking portion 50e of the electrode body 50 is pressed in the electrode body thickness direction FH. And by pressing the external communication portion 50ebc, the outflow of the impregnated electrolytic solution 3a to the outside of the electrode stacking portion 50e through the external communication portion 50ebc is restricted.

[0068] In the battery 100 of the second embodiment as well, the first main wall portion 111 and the second main wall portion 112 of the case 110 elastically compress the electrode stacking portion 50e of the electrode body 50 in the electrode body thickness direction FH. That is, this battery 100 is a self-compression type that elastically compresses the electrode stacking portion 50e of the electrode body 50 by the battery 100 itself. For this reason, when using the battery 100, it is not necessary to separately use a restraining member, or external restraint by a simple restraining member is sufficient. Further, since the case 110 is formed by joining the lid member 131 forming the first main wall portion 111 to the main body member 121 forming the second main wall portion 112 and the four side wall portions 13 to 16, the self-compression type battery 100 can be easily manufactured, and an inexpensive battery 100 can be obtained.

[0069] Further, the battery 100 has a central portion pressing portion 141 that presses the central portion 50ea of the electrode stacking portion 50e of the electrode body 50, and a communication portion pressing portion 146 that presses the external communication portion 50ebc of the outer peripheral portion 50eb of the electrode stacking portion 50e of the electrode body 50 to restrict the outflow of the impregnated electrolytic solution 3a to the outside of the electrode stacking portion 50e. For this reason, the electrode stacking portion 50e can be pressed over a wider range, and the outflow of the impregnated electrolytic solution 3a to the outside of the electrode stacking portion 50e through the external communication portion 50ebc can be suppressed.

[0070] Furthermore, in the second embodiment, since the communication part pressing part 146 is provided on the second main wall part 112 of the case 110, there is no need to dispose an intervening member having the communication part pressing part between the second main wall part 112 of the case 110 and the electrode stacking part 50e of the electrode body 50. Also, since the central part pressing part 141 is provided on the first main wall part 111 of the case 110, there is no need to dispose an intervening member having the central part pressing part between the first main wall part 111 of the case 110 and the electrode stacking part 50e of the electrode body 50.

[0071] Next, the manufacturing method of the battery 100 of the second embodiment will be described. First, in the accommodation step S1, the electrode body 50 wrapped with an insulating holder is accommodated in the main body member 121 to which the positive electrode terminal 60 and the negative electrode terminal 70 are fixed. In the second embodiment, no intervening member is disposed. Then, in the same manner as in the first embodiment, the positive electrode current collecting part 50c and the negative electrode current collecting part 50d of the electrode body 50 and the positive electrode terminal 60 and the negative electrode terminal 70 fixed to the main body member 121 are respectively laser welded.

[0072] Next, in the pressing and compressing step S2, the lid member 131 is disposed on the electrode body 50 accommodated in the main body member 121, and an external force Fa is applied to the first main wall part 111 formed by the lid member 131 and the second main wall part 112 of the main body member 121 to press and compress the electrode stacking part 50e of the electrode body 50 in the electrode body thickness direction FH. At this time, in the second embodiment, the central part 50ea and the external communication part 50ebc of the electrode stacking part 50e are pressed in the electrode body thickness direction FH by the central part pressing part 141 and the communication part pressing part 146 provided on the case 110. Then, the lid peripheral edge part 131f of the lid member 131 is brought into contact with the opening peripheral edge part 121f of the opening part 121c of the main body member 121 over the entire circumference. This step is performed using the same pressing device 500 (see FIG. 9) as in the first embodiment.

[0073] Next, in the joining step S3, in the same manner as in the first embodiment, the lid peripheral edge part 131f of the lid member 131 is laser welded to the opening peripheral edge part 121f of the main body member 121 over the entire circumference to form the case 110. After that, in the same manner as in the first embodiment, the release step S4, the liquid injection and sealing step S5, and the first charging and aging step S6 are performed to complete the battery 100.

[0074] In the manufacturing method of the battery 100 according to the second embodiment, in the housing step S1, the electrode body 50 is housed in the bottomed rectangular tubular main body member 121 forming the second main wall portion 112 and the four side wall portions 13 to 16, so that the electrode body 50 can be easily housed in the main body member 121. Then, by performing the pressing and compressing step S2, the joining step S3, and the releasing step S4, the self-compressing type battery 100 can be easily manufactured. In particular, in the second embodiment, since the intervening member forming the communication portion pressing portion is not disposed in the main body member 121, the housing step S1 and the pressing and compressing step S2 can be easily performed. Further, since the intervening member forming the central portion pressing portion is not disposed in the main body member 121, the housing step S1 and the pressing and compressing step S2 can be easily performed. In addition, the same parts as those in the first embodiment have the same operational effects as those in the first embodiment.

[0075] (Embodiment 3) Next, a third embodiment will be described (see FIGS. 14 to 16). The description of the same parts as those in the first or second embodiment will be omitted or simplified. The batteries 1 and 100 of the first and second embodiments include the flat wound type electrode body 50 (see FIG. 6). On the other hand, the battery 200 of the third embodiment includes the laminated type electrode body 250 (see FIG. 16).

[0076] In the battery 1 of the first embodiment, the first intervening member 40 having the central portion pressing portion 41 is disposed between the first main wall portion 11 of the case 10 and the electrode lamination portion 50e of the electrode body 50, and the second intervening member 45 having the communication portion pressing portion 46 is disposed between the second main wall portion 12 of the case 10 and the electrode lamination portion 50e of the electrode body 50. On the other hand, also in the third embodiment, the first intervening member 40 having the central portion pressing portion 41 is disposed between the first main wall portion 11 of the case 10 and the electrode lamination portion 250e of the electrode body 250, and the second intervening member 245 having the communication portion pressing portion 246 is disposed between the second main wall portion 12 of the case 10 and the electrode lamination portion 250e of the electrode body 250 (see FIGS. 14 and 15). However, in the third embodiment, since the electrode body 250 is of the laminated type, the form of the communication portion pressing portion 246 is different from that of the communication portion pressing portion 46 of the first embodiment.

[0077] First, the laminated electrode body 250 according to Embodiment 3 will be described (see FIG. 16). This electrode body 250 has a rectangular parallelepiped shape, and a plurality of rectangular positive electrode plates (electrode plates) 251 and a plurality of rectangular negative electrode plates (electrode plates) 254 are alternately laminated and integrated in the electrode body thickness direction FH via a rectangular separator 257 made of a resin porous film. The electrode body 250 has a positive electrode current collector portion 250c located at an end of one side IH1 in the electrode body long side direction IH, a negative electrode current collector portion 250d located at an end of the other side IH2 in the electrode body long side direction IH, and an electrode laminated portion 250e located between them.

[0078] Among these, the electrode laminated portion 250e is a rectangular parallelepiped portion where the positive electrode plate 251, the negative electrode plate 254, and the separator 257 are laminated in a flat plate shape in the electrode body thickness direction FH. This electrode laminated portion 250e has a rectangular parallelepiped central portion 250ea located inside GH1 in the laminated portion spreading direction GH orthogonal to the electrode body thickness direction FH, and a rectangular annular outer peripheral portion 250eb surrounding the central portion 250ea from the outside GH2 in the laminated portion spreading direction GH. In the electrode body 250 of Embodiment 3, since the entire outer peripheral portion 250eb communicates with the outside of the electrode body 250, the entire outer peripheral portion 250eb is an external communication portion 250ebc. Therefore, in Embodiment 3, the impregnated electrolyte 3a in the electrode laminated portion 250e flows out of the electrode body 250 directly or through the positive electrode current collector portion 250c or the negative electrode current collector portion 250d from the external communication portion 250ebc as shown by the arrow P indicating the movement of the impregnated electrolyte 3a in FIG. 16 as the battery 200 is used.

[0079] This electrode body 250 is housed in the case 10 in a posture where the electrode body long side direction IH is parallel to the case width direction BH, the electrode body short side direction JH is parallel to the case height direction AH, and the electrode body thickness direction FH is parallel to the case thickness direction CH. Also, the electrode body 250 is housed in the case 10 in a state where the electrode laminated portion 250e is compressed in the electrode body thickness direction FH (case thickness direction CH). That is, the battery 200 is a self-compressing type battery, the case 10 is elastically deformed, and the first main wall portion 11 and the second main wall portion 12 of the case 10 elastically compress the electrode laminated portion 250e of the electrode body 250 in the electrode body thickness direction FH.

[0080] The positive electrode plate 251 is composed of a rectangular positive current collector foil 252 and rectangular positive electrode active material layers 253 formed on both main surfaces of the positive current collector foil 252. At one end of the positive electrode plate 251 in the long side direction, the positive electrode active material layer 253 does not exist on the positive current collector foil 252, and the positive current collector foil 252 is exposed. This exposed portion of the positive current collector foil 252 protrudes from the electrode stacking portion 250e to one side IH1 in the electrode body long side direction IH in the electrode body 250, forming the aforementioned positive current collecting portion 250c. The positive current collecting portion 250c is connected to the positive electrode terminal 60.

[0081] The negative electrode plate 254 is composed of a rectangular negative current collector foil 255 and rectangular negative electrode active material layers 256 formed on both main surfaces of the negative current collector foil 255. At one end of the negative electrode plate 254 in the long side direction, the negative electrode active material layer 256 does not exist on the negative current collector foil 255, and the negative current collector foil 255 is exposed. This exposed portion of the negative current collector foil 255 protrudes from the electrode stacking portion 250e to the other side IH2 in the electrode body long side direction IH in the electrode body 250, forming the aforementioned negative current collecting portion 250d. The negative current collecting portion 250d is connected to the negative electrode terminal 70.

[0082] Next, the first intervening member 40 and the second intervening member 245 will be described (see FIGS. 14 and 15). The first intervening member 40 is the same as that in the first embodiment (see FIG. 4). On the other hand, the second intervening member 245 is different from the second intervening member 45 in the first embodiment. The second intervening member 245 of the third embodiment consists of a base portion 247 and a communication portion pressing portion 246. The communication portion pressing portion 246 has a rectangular annular shape and extends in the case width direction BH near the upper end portion and the lower end portion in the case height direction AH, and extends in the case height direction AH near both end portions in the case width direction BH. The communication portion pressing portion 246 projects toward the inner side CH3 in the thickness direction in the case thickness direction CH (toward the electrode stacking portion 250e of the electrode body 250) from the base portion 47. The communication portion pressing portion 246 presses the external communication portion 250ebc of the electrode stacking portion 250e of the electrode body 250 in the electrode body thickness direction FH by the elastic compression by the first main wall portion 11 and the second main wall portion 12 of the case 10, and restricts the impregnated electrolytic solution 3a from flowing out of the electrode stacking portion 250e through the external communication portion 250ebc.

[0083] The battery 200 of the third embodiment is also a self-compression type that elastically compresses the electrode stacking portion 250e of the electrode body 250 by the battery 200 itself. Therefore, when using the battery 200, it is not necessary to separately use a restraining member, or external restraint by a simple restraining member is sufficient. Further, the battery 200 has a central portion pressing portion 41 that presses the central portion 250ea of the electrode stacking portion 250e of the electrode body 250, and a communication portion pressing portion 246 that presses the external communication portion 250ebc of the electrode stacking portion 250e of the electrode body 250 to restrict the impregnated electrolytic solution 3a from flowing out of the electrode stacking portion 250e. For this reason, the electrode stacking portion 250e can be pressed over a wider range, and the impregnated electrolytic solution 3a can be suppressed from flowing out of the electrode stacking portion 250e through the external communication portion 250ebc.

[0084] Furthermore, in the third embodiment, the second intervening member 245 is disposed between the second main wall portion 12 of the case 10 and the electrode stacking portion 250e of the electrode body 250, and the communication portion pressing portion 246 is provided on the second intervening member 245. For this reason, it is not necessary to provide a communication portion pressing portion on the second main wall portion 12 of the case 10. Further, the first intervening member 40 is disposed between the first main wall portion 11 of the case 10 and the electrode stacking portion 250e of the electrode body 250, and the central portion pressing portion 41 is provided on the first intervening member 40. For this reason, it is not necessary to provide a central portion pressing portion on the first main wall portion 11 of the case 10.

[0085] Note that the battery 200 of the third embodiment is manufactured in the same manner as the battery 1 of the first embodiment. That is, in the accommodation step S1, the electrode body 250, the first intervening member 40, and the second intervening member 245 are accommodated in the main body member 21 with the first intervening member 40 and the second intervening member 245 stacked on the electrode body 250. Thereafter, in the pressing and compressing step S2, an external force Fa is applied to the first main wall portion 11 and the second main wall portion 12 by the pressing device 500 to press the second intervening member 245, the electrode stacking portion 250e of the electrode body 250, and the first intervening member 40 in the electrode body thickness direction FH, and compress the electrode stacking portion 250e. Subsequently, in the joining step S3, the lid peripheral portion 31f of the lid member 31 is laser welded to the opening peripheral portion 21f of the opening portion 21c of the main body member 21 over the entire circumference to form the case 10. Thereafter, in the releasing step S4, the external force Fa is released. Further, a liquid injection and sealing step S5 and a first charging and aging step S6 are performed to complete the battery 200.

[0086] In the manufacturing method of the battery 200 of the third embodiment, in the accommodation step S1, the electrode body 250, the first intervening member 40, and the second intervening member 245 are accommodated in the bottomed rectangular tube-shaped main body member 21 formed by the second main wall portion 12 and the four side wall portions 13 to 16. Therefore, the electrode body 250, the first intervening member 40, and the second intervening member 245 can be easily accommodated in the main body member 21, and the self-compression type battery 200 can be easily manufactured. In particular, in the third embodiment, since the battery 200 is manufactured using the second intervening member 245, a battery 200 in which the external communication portion 250ebc of the electrode stacking portion 250e of the electrode body 250 is appropriately pressed by the communication portion pressing portion 246 of the second intervening member 245 can be manufactured. Further, since the battery 200 is manufactured using the first intervening member 40, a battery 200 in which the central portion 250ea of the electrode stacking portion 250e of the electrode body 250 is appropriately pressed by the central portion pressing portion 41 of the first intervening member 40 can be manufactured. In addition, the same parts as those in the first or second embodiment have the same operational effects as those in the first or second embodiment.

[0087] (Embodiment 4) Next, a fourth embodiment will be described. Note that descriptions of parts similar to any of the first to third embodiments will be omitted or simplified. In the battery 100 of the second embodiment, the central portion pressing part 141 is provided on the first main wall part 111 of the case 110, and the communication part pressing part 146 is provided on the second main wall part 112 of the case 110. On the other hand, also in the battery 300 of the fourth embodiment, the central portion pressing part 141 is provided on the first main wall part 111 of the case 310, and the communication part pressing part 346 is provided on the second main wall part 312 of the case 310. However, in the third embodiment, since the electrode body 250 is a stacked type, the form of the communication part pressing part 346 is different from that of the communication part pressing part 146 of the second embodiment.

[0088] The electrode body 250 of the fourth embodiment is the same as that of the third embodiment (see FIG. 16). Also, among the case 310 of the fourth embodiment, the first main wall part 111 having the central portion pressing part 141 (see FIG. 12), and the four side wall parts 13, 14, 15, 16 are the same as the case 110 of the second embodiment. On the other hand, among the case 310 of the fourth embodiment, the second main wall part 312 is different from the second main wall part 112 of the case 110 of the second embodiment (see FIGS. 17 and 18).

[0089] Specifically, the second main wall part 312 has a rectangular ring-shaped communication part pressing part 346. This communication part pressing part 346 extends in the case width direction BH near the upper end part and the lower end part in the case height direction AH, respectively, and extends in the case height direction AH near both end parts in the case width direction BH, respectively. The communication part pressing part 346 protrudes toward the inside in the thickness direction CH3 in the case thickness direction CH (toward the electrode stacking part 250e of the electrode body 250). The communication part pressing part 346 presses the external communication part 250ebc in the electrode stacking part 250e of the electrode body 250 in the electrode body thickness direction FH by the elastic compression by the first main wall part 111 and the second main wall part 312 of the case 310, and restricts the impregnated electrolytic solution 3a from flowing out of the electrode stacking part 250e through the external communication part 250ebc.

[0090] Since the battery 300 of the fourth embodiment is also a self-compression type that elastically compresses the electrode stacking portion 250e of the electrode body 250 by the battery 300 itself, it is not necessary to separately use a restraining member when using the battery 300, or external restraint by a simple restraining member is sufficient. Also, since the case 310 is formed by joining a lid member 131 forming the first main wall portion 111 to a main body member 321 forming the second main wall portion 312 and the four side wall portions 13 to 16, the self-compression type battery 300 can be easily manufactured, and an inexpensive battery 300 can be obtained. The battery 300 also includes a central pressing portion 141 that presses the central portion 250ea of the electrode stacking portion 250e of the electrode body 250, and a communication portion pressing portion 346 that presses the external communication portion 250ebc of the electrode stacking portion 250e of the electrode body 250 to restrict the outflow of the impregnated electrolyte 3a to the outside of the electrode stacking portion 250e. Therefore, the electrode stacking portion 250e can be pressed over a wider range, and the outflow of the impregnated electrolyte 3a to the outside of the electrode stacking portion 250e through the external communication portion 250ebc can be suppressed.

[0091] Furthermore, in the fourth embodiment, since the communication portion pressing portion 346 is provided on the second main wall portion 312 of the case 310, there is no need to arrange an intervening member having a communication portion pressing portion between the second main wall portion 312 of the case 310 and the electrode stacking portion 250e of the electrode body 250. Also, since the central pressing portion 141 is provided on the first main wall portion 111 of the case 310, there is no need to arrange an intervening member having a central pressing portion between the first main wall portion 111 of the case 310 and the electrode stacking portion 250e of the electrode body 250.

[0092] Note that the battery 300 of the fourth embodiment is manufactured in the same manner as the battery 100 of the second embodiment. That is, in the accommodation step S1, the electrode body 250 is accommodated in the main body member 321. Then, in the pressing and compressing step S2, an external force Fa is applied to the first main wall portion 111 and the second main wall portion 312 by the pressing device 500, and the electrode stacking portion 250e of the electrode body 250 is pressed and compressed in the electrode body thickness direction FH. Subsequently, in the joining step S3, the lid peripheral portion 131f of the lid member 131 is laser-welded to the opening peripheral portion 321f of the opening portion 321c of the main body member 321 over the entire circumference to form the case 310. Then, in the release step S4, the external force Fa is released. Further, the liquid injection and sealing step S5 and the first charging and aging step S6 are performed to complete the battery 300.

[0093] In the manufacturing method of the battery 300 of the fourth embodiment, in the accommodation step S1, the electrode body 250 is accommodated in the bottomed rectangular tube-shaped main body member 321 that forms the second main wall portion 312 and the four side wall portions 13 to 16. Therefore, the electrode body 250 can be easily accommodated in the main body member 321, and the self-compression type battery 300 can be easily manufactured. In particular, in the fourth embodiment, since the intervening member forming the communication portion pressing portion and the intervening member forming the central portion pressing portion are not arranged in the main body member 321, the accommodation step S1 and the pressing and compressing step S2 can be easily performed. In addition, the parts similar to any of the first to third embodiments have the same effects as any of the first to third embodiments.

[0094] As described above, the present invention has been described with reference to the first to fourth embodiments. However, the present invention is not limited to the first to fourth embodiments, and it goes without saying that it can be appropriately modified and applied without departing from the gist thereof.

Description of Reference Numerals

[0095] 1, 100, 200, 300 Battery (Power Storage Device) 3a Impregnated Electrolyte 10, 110, 310 Case 11, 111 First Main Wall Portion 12, 112, 312 Second Main Wall Portion 13 First Side Wall Portion (Upper Wall Portion) 14 Second Side Wall Portion (Lower Wall Portion) 15 Third side wall part 16 Fourth side wall part 21, 121, 321 Body member 21c, 121c, 321c Opening 21f, 121f, 321f Opening peripheral edge part 31, 131 Cover member 31f, 131f Cover peripheral edge part 40 First intervening member 41, 141 Central part pressing part 45, 245 Second intervening member 46, 146, 246, 346 Communication part pressing part 50, 250 Electrode body 50e, 250e Electrode laminate part 50ea, 250ea (Central part of the electrode laminate part) 50eb, 250eb (Outer peripheral part of the electrode laminate part) 50ebc, 250ebc (External communication part of the outer peripheral part of the electrode laminate part) 51, 251 Positive electrode plate (electrode plate) 54, 254 Negative electrode plate (electrode plate) 57, 257 Separator AH Case height direction AH1 Upper side AH2 Lower side CH Case thickness direction DH Electrode body axis direction FH Electrode body thickness direction GH Laminated part spreading direction GH1 (Inner side of the laminated part spreading direction) GH2 (Outer side of the laminated part spreading direction) IH Electrode body long side direction IH1 (One side of the electrode body long side direction) IH2 (The other side of the electrode body long side direction) JH Electrode body short side direction Fa External force S1 Accommodation process S2 Pressing and compressing process S3 Joining process S4 Release process

Claims

1. A case, an electrode body housed in the case, and an impregnated electrolytic solution impregnated in the electrode body, comprising: The case has a rectangular parallelepiped box shape and has a rectangular first main wall portion, a rectangular second main wall portion facing the first main wall portion, and four rectangular side wall portions connecting between the first main wall portion and the second main wall portion and extending in the case thickness direction. The electrode body includes an electrode plate and has a rectangular parallelepiped electrode laminate portion in which the electrode plates are laminated in the electrode body thickness direction, and the electrode body thickness direction is housed in the case in a posture parallel to the case thickness direction. The electrode laminate portion is a central portion located inside in the laminate portion spreading direction orthogonal to the electrode body thickness direction, and an outer peripheral portion surrounding the central portion from the outside in the laminate portion spreading direction. The outer peripheral portion is a power storage device including an external communication portion communicating with the outside of the electrode body, wherein the case is a bottomed rectangular tubular body member forming the second main wall portion and the four side wall portions and having a rectangular opening formed by the four side wall portions, a rectangular lid member forming the first main wall portion and having a lid peripheral portion joined to the entire opening peripheral edge of the opening of the body member, wherein the first main wall portion and the second main wall portion of the case elastically compress the electrode laminate portion of the electrode body in the electrode body thickness direction, a central portion pressing portion that presses the central portion of the electrode laminate portion of the electrode body in the electrode body thickness direction by elastic compression by the first main wall portion and the second main wall portion, a communication portion pressing portion that presses the external communication portion of the electrode laminate portion of the electrode body in the electrode body thickness direction by elastic compression by the first main wall portion and the second main wall portion and restricts the impregnated electrolytic solution from flowing out of the electrode laminate portion through the external communication portion, wherein an intervening member is provided between at least one of the first main wall portion of the case and the electrode laminate portion of the electrode body and between the second main wall portion of the case and the electrode laminate portion of the electrode body, and the communication portion pressing portion is provided on the intervening member. A power storage device.

2. The power storage device according to claim 1, wherein an intervening member is provided between at least one of the first main wall portion of the case and the electrode laminate portion of the electrode body and between the second main wall portion of the case and the electrode laminate portion of the electrode body, and the central portion pressing portion is provided on the intervening member. A power storage device. ​

3. The power storage device according to claim 1, wherein the central pressing portion is provided on at least one of the first main wall portion and the second main wall portion of the case Power storage device.

4. A case, an electrode body housed in the case, and an impregnated electrolytic solution impregnated in the electrode body, and the case is in the shape of a rectangular parallelepiped box, having a rectangular first main wall portion, a rectangular second main wall portion facing the first main wall portion, and four rectangular side wall portions connecting between the first main wall portion and the second main wall portion and extending in the case thickness direction, the electrode body includes electrode plates and has a rectangular parallelepiped-shaped electrode laminate portion in which the electrode plates are laminated in the electrode body thickness direction, and the electrode body thickness direction is housed in the case in a posture parallel to the case thickness direction, the electrode laminate portion has a central portion located inside in the laminate portion spreading direction orthogonal to the electrode body thickness direction, and an outer peripheral portion surrounding the central portion from the outside in the laminate portion spreading direction, the outer peripheral portion includes an external communication portion communicating with the outside of the electrode body Power storage device, wherein the case has a bottomed rectangular tube-shaped main body member forming the second main wall portion and the four side wall portions, and having a rectangular opening formed by the four side wall portions, and a rectangular lid member forming the first main wall portion and having a lid peripheral portion joined to the opening peripheral edge of the opening of the main body member over the entire circumference, the first main wall portion and the second main wall portion of the case elastically compress the electrode laminate portion of the electrode body in the electrode body thickness direction, due to the elastic compression by the first main wall portion and the second main wall portion, a central pressing portion that presses the central portion of the electrode laminate portion of the electrode body in the electrode body thickness direction, and due to the elastic compression by the first main wall portion and the second main wall portion, a communication portion pressing portion that presses the external communication portion of the electrode laminate portion of the electrode body in the electrode body thickness direction and restricts the impregnated electrolytic solution from flowing out of the electrode laminate portion through the external communication portion, an intervening member is provided between at least one of the first main wall portion of the case and the electrode laminate portion of the electrode body and between the second main wall portion of the case and the electrode laminate portion of the electrode body, the central pressing portion is provided on the intervening member Power storage device.

5. The power storage device according to claim 4, wherein the communication portion pressing portion is provided on at least one of the first main wall portion and the second main wall portion of the case Storage device.

6. A case, An electrode body housed in the case, An impregnated electrolytic solution impregnated in the electrode body, comprising: The case is in the shape of a rectangular parallelepiped box, having a rectangular first main wall portion, a rectangular second main wall portion facing the first main wall portion, and four rectangular side wall portions connecting between the first main wall portion and the second main wall portion and extending in the case thickness direction. The electrode body includes electrode plates and has a rectangular parallelepiped-shaped electrode laminate portion in which the electrode plates are laminated in the electrode body thickness direction, and the electrode body thickness direction is housed in the case in a posture parallel to the case thickness direction. The electrode laminate portion is A central portion located inside in the laminate portion spreading direction orthogonal to the electrode body thickness direction, and An outer peripheral portion surrounding the central portion from the outside in the laminate portion spreading direction. The outer peripheral portion is Including an external communication portion communicating with the outside of the electrode body. The case is A bottomed rectangular tubular body member forming the second main wall portion and the four side wall portions, and having a rectangular opening formed by the four side wall portions. A rectangular lid member forming the first main wall portion, and having a lid peripheral portion joined to the opening peripheral edge of the opening of the body member over the entire circumference. The first main wall portion and the second main wall portion of the case elastically compress the electrode laminate portion of the electrode body in the electrode body thickness direction. A central portion pressing portion that presses the central portion of the electrode laminate portion of the electrode body in the electrode body thickness direction by elastic compression by the first main wall portion and the second main wall portion. By elastic compression by the first main wall portion and the second main wall portion, a communication portion pressing portion that presses the external communication portion of the electrode laminate portion of the electrode body in the electrode body thickness direction and restricts the impregnated electrolytic solution from flowing out of the electrode laminate portion through the external communication portion. A method for manufacturing a storage device, comprising: A housing step of housing the electrode body in the body member. A pressing and compressing step of disposing the lid member on the electrode body housed in the body member, applying an external force to the first main wall portion formed by the lid member and the second main wall portion of the body member, and pressing and compressing the electrode laminate portion of the electrode body in the electrode body thickness direction. A joining step of joining the lid peripheral portion of the lid member to the opening peripheral edge of the opening of the body member over the entire circumference in a state where the electrode body is pressed and compressed to form the case. A releasing step of releasing the external force after the joining step. The storage device is Between at least one of the first main wall portion of the case and the electrode stack portion of the electrode body, and between at least one of the second main wall portion of the case and the electrode stack portion of the electrode body, an intervening member forming the communication portion pressing portion is provided. The accommodating step is accommodating the electrode body and the intervening member by stacking the intervening member on the electrode body. The pressing and compressing step is pressing the electrode body and the intervening member in the thickness direction of the electrode body. A method for manufacturing a power storage device.

7. A method for manufacturing a power storage device according to claim 6, wherein the power storage device is Between at least one of the first main wall portion of the case and the electrode stack portion of the electrode body, and between at least one of the second main wall portion of the case and the electrode stack portion of the electrode body, an intervening member forming the central portion pressing portion is provided. The accommodating step is accommodating the electrode body and the intervening member by stacking the intervening member on the electrode body. The pressing and compressing step is pressing the electrode body and the intervening member in the thickness direction of the electrode body. A method for manufacturing a power storage device.

8. A power storage device according to claim 6, wherein the central portion pressing portion is provided on at least one of the first main wall portion and the second main wall portion of the case, and the pressing and compressing step is pressing the central portion of the electrode body in the thickness direction of the electrode body by the central portion pressing portion provided on the case. A method for manufacturing a power storage device.

9. A case, an electrode body accommodated in the case, and an impregnated electrolytic solution impregnated in the electrode body, and the case is in the shape of a rectangular parallelepiped box, having a rectangular first main wall portion, a rectangular second main wall portion facing the first main wall portion, and four rectangular side wall portions connecting between the first main wall portion and the second main wall portion and extending in the case thickness direction. The electrode body includes electrode plates, has a rectangular parallelepiped-shaped electrode stack portion in which the electrode plates are stacked in the thickness direction of the electrode body, and is accommodated in the case in a posture where the thickness direction of the electrode body is parallel to the thickness direction of the case. The electrode stack portion is a central portion located inside in the expanding direction of the stack portion orthogonal to the thickness direction of the electrode body, and an outer peripheral portion surrounding the central portion from the outside in the expanding direction of the stack portion, and the outer peripheral portion is including an external communication portion communicating with the outside of the electrode body, and the case is a bottomed rectangular tube-shaped main body member forming the second main wall portion and the four side wall portions, and having a rectangular opening formed by the four side wall portions. a rectangular lid member forming the first main wall portion and having a lid peripheral edge portion joined to the entire periphery of the opening peripheral edge of the opening of the main body member; the first main wall portion and the second main wall portion of the case elastically compress the electrode laminate portion of the electrode body in the thickness direction of the electrode body; a central portion pressing portion that presses the central portion of the electrode laminate portion of the electrode body in the thickness direction of the electrode body by elastic compression by the first main wall portion and the second main wall portion; a communication portion pressing portion that presses the external communication portion of the electrode laminate portion of the electrode body in the thickness direction of the electrode body by elastic compression by the first main wall portion and the second main wall portion, and restricts the impregnated electrolytic solution from flowing out of the electrode laminate portion through the external communication portion; A method for manufacturing a power storage device, comprising: a housing step of housing the electrode body in the main body member; a pressing and compressing step of disposing the lid member on the electrode body housed in the main body member, applying an external force to the first main wall portion formed by the lid member and the second main wall portion of the main body member, and pressing and compressing the electrode laminate portion of the electrode body in the thickness direction of the electrode body; a joining step of joining the lid peripheral edge portion of the lid member to the entire periphery of the opening peripheral edge of the opening of the main body member in a state where the electrode body is pressed and compressed, to form the case; a releasing step of releasing the external force after the joining step; The power storage device is provided with an intervening member forming the central portion pressing portion between at least one of the first main wall portion of the case and the electrode laminate portion of the electrode body and between the second main wall portion of the case and the electrode laminate portion of the electrode body; The housing step is housing the electrode body and the intervening member by stacking the intervening member on the electrode body; The pressing and compressing step is pressing the electrode body and the intervening member in the thickness direction of the electrode body A method for manufacturing a power storage device.

10. A method for manufacturing a power storage device according to Claim 9, the communication portion pressing portion is provided on at least one of the first main wall portion and the second main wall portion of the case; The pressing and compressing step is pressing the external communication portion of the electrode body in the thickness direction of the electrode body by the communication portion pressing portion provided on the case A method for manufacturing a power storage device.

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