JP2012209131A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery in which removal of air bubbles generated in a stacked electrode body is promoted to improve battery performance with a simple configuration.SOLUTION: A battery 1 includes a stacked electrode body 6 in which a first electrode plate and a second electrode plate are stacked with a separator 5 in between, an electrolytic solution or electrolyte, a first electrode terminal connected electrically to the first electrode plate, and a second electrode terminal connected electrically to the second electrode plate. It further includes a battery can in which the electrolytic solution or electrolyte and the stacked electrode body 6 are stored in a sealed manner, and a throttling part which is formed between the stacked electrode body and the battery can in such manner as integral with or separate from the battery can, with its thickness gradually decreasing as advances in throttling direction.

Description

  The present invention relates to a battery, particularly a battery with improved battery performance.

There are primary batteries that perform only discharge and secondary batteries that can be charged and discharged. These generally have a structure in which an electrode plate, that is, a laminated electrode body in which a positive electrode plate and a negative electrode plate are laminated via a separator is sealed together with an electrolytic solution or the like in a battery container.
When the battery is charged or discharged, bubbles are generally generated inside the battery container due to a reaction of the positive electrode active material, the negative electrode active material, the electrolytic solution, or the like.
If the bubbles stay inside the laminated electrode body, the portion of the electrode plate of the laminated electrode body that is in contact with the bubbles is difficult to contribute to ionic conduction between the electrode plates, which may deteriorate the battery performance. There is.
For this reason, a battery (see Patent Document 1 and Patent Document 2) has been developed in which the bubble channel is formed inside the battery container to prevent deterioration of battery performance.

JP 2003-282143 A JP 2003-151635 A

However, since the battery of Patent Document 1 is provided with a spacer in which a bubble channel is formed between the wall surface of the battery container and the laminated electrode body, it is sufficient to remove bubbles generated inside the laminated electrode body. It was difficult to do.
On the other hand, in the battery of Patent Document 2, since the glass fiber, which is a member in which a bubble channel is formed, is disposed inside the laminated electrode body, the bubbles generated inside the laminated electrode body can be removed. However, since it is necessary to arrange the members other than the electrode plate and the separator inside the laminated electrode body, the size of the battery when the battery performance is the same is arranged in the battery without arranging the member. The size can be reduced as compared with the battery. That is, the battery may be enlarged by arranging the member. Moreover, since it is necessary to add the said member, there exists a possibility that manufacturing cost may rise.
Accordingly, the present invention provides a battery with improved battery performance by facilitating the removal of bubbles generated inside the laminated electrode body with a simple configuration in which the above members are not arranged inside the laminated electrode body. Objective.

In order to achieve the above object, a battery according to the present invention includes a laminated electrode body in which a first electrode plate and a second electrode plate are laminated via a separator, an electrolytic solution or an electrolyte, and an electric current connected to the first electrode plate. Battery comprising: a first electrode terminal connected to the second electrode terminal; and a second electrode terminal electrically connected to the second electrode plate, wherein the electrolyte solution or the electrolyte and the laminated electrode body are hermetically sealed. And a squeezing portion formed integrally or separately with the battery container between the stacked electrode body and the battery container and gradually reducing its thickness as it advances in the squeezing direction. .

  That is, when the battery is charged or discharged, the laminated electrode body expands, but by having a squeezed portion between the battery container and the laminated electrode body, bubbles generated inside the battery container with the expansion are squeezed out. The bubbles can be lifted up while squeezing in the direction. That is, since the bubbles can be promoted to be prevented from staying inside the laminated electrode body, a battery having excellent performance can be provided.

  According to the battery of the present invention, it is possible to provide a battery with improved battery performance by promoting the removal of bubbles generated inside the laminated electrode body with a simple configuration.

It is a schematic diagram of the battery of an embodiment of the present invention. 1A is a schematic perspective view from the front of the battery, and FIG. 1B is a schematic YZ cross-sectional view taken along line AA ′ of FIG. 1A. It is a schematic diagram of the 1st auxiliary sheet | seat 12a shown in FIG. FIG. 2A is an XZ plane schematic diagram of the surface on the wall surface side of the closest battery case, and FIG. 2B is a YZ plane schematic diagram (however, the direction away from the wall surface is the + Y direction). It is. 2C is a schematic cross-sectional view taken along line BB ′ of FIG. 2A, and FIG. 2D is a schematic cross-sectional view taken along line CC ′ of FIG. 2A. FIG. FIG. 2 is a schematic cross-sectional view illustrating a modification of the battery of FIG. 1 and corresponding to FIG.

The battery according to the embodiment of the present invention is formed between the laminated electrode body and the battery container, or is formed integrally with or separately from the battery container, and gradually decreases in thickness as it proceeds in the “squeezing direction” described later. The “squeezing part” uses the volume change of the laminated electrode body due to charging or discharging of the battery to squeeze out bubbles generated near each electrode plate of the laminated electrode body in the squeezing direction, and as a result, the direction in which the buoyancy of the bubbles works One feature is to reduce the retention of the bubbles in these electrode plates by floating the bubbles in the direction opposite to the direction in which gravity acts (hereinafter referred to as “squeezing function”). Hereinafter, it will be described in detail with reference to the drawings.
In addition, as a battery of embodiment and its modification, although any battery, such as a primary battery or a secondary battery, can be used, it is a battery which can be charged / discharged as an example of a battery, for example, a storage battery. A description will be given using a lithium ion secondary battery.

Hereinafter, the battery 1 of the present embodiment will be described with reference to FIG. First, the outline of the configuration of the battery 1 will be described, and then the “squeezing function” will be described.
FIG. 1A is a perspective schematic view from the front (XZ plane) of the battery 1, and FIG. 1B is a schematic cross-sectional view in the YZ plane of the AA ′ line of FIG. . Note that FIG. 1 used below uses the same orthogonal coordinate system. Moreover, since FIG. 1A is a schematic diagram for promoting understanding, not all the components shown in FIG. 1B are described.

First, the battery 1 has a rectangular conductivity (for example, made of a metal such as an aluminum alloy) having a substantially rectangular bottom surface on the XY plane and having wall surfaces extending in the Z-axis direction from all sides of the substantially rectangular shape. Container body 2, laminated electrode body 6 that is housed in container body 2, and positive electrode plate 3 and negative electrode plate 4 are laminated via separator 5, and container body 2 after housing laminated electrode body 6 in container body 2. (Container body 2 and lid 7 are sealed by laser welding or the like to form a “battery container”). Although not shown, an electrolytic solution or an electrolyte is stored in the battery container.
Here, the lid 7 is made of the same material as the container body 2. The lid 7 has a cylindrical electrode terminal (a positive terminal 8 and a negative terminal 9) having a cylindrical shape (a cross-sectional shape in the XY plane is substantially a diameter r) disposed through the lid 7, and an electrode terminal. An insulating resin 10 (for example, a plastic resin) that is fixed to the lid 7 and that electrically insulates between the electrode terminal and the lid 7 is formed.
As described above, in the present embodiment, the conductive battery container is described as an example. Therefore, in order to electrically insulate between the laminated electrode body 6 and the battery container, the bottom surface is substantially formed on the bottom surface inside the container body 2. Insulating resin plates 11 (for example, plastic resin sheets) having the same shape and dimensions are arranged. A pair of first auxiliary sheets 12 (12a, 12b) and a pair of second auxiliary sheets 13 made of an insulating resin, which will be described later, are arranged on the wall surface other than the bottom surface of the container body 2.
Specifically, the laminated electrode body 6 is sandwiched between the pair of first auxiliary sheets 12 (12a, 12b) from the −Y direction and the + Y direction, and is also paired with the pair of second auxiliary sheets 13 from the −X direction and the + X direction. The four auxiliary sheets are sandwiched and fixed with insulating tape to form one unit, and the unit is inserted into the container body 2. At this time, these auxiliary sheets function as an insertion guide for preventing the laminated electrode body 6 from coming into direct contact with the container body 2 and damaging it and smoothly inserting the laminated electrode body 2 into the container body 2. Can do.

As an example, the multilayer electrode body 6 will be described below as a multilayer electrode body in which a plurality of positive electrode plates 3 and a plurality of negative electrode plates 4 are sequentially laminated via separators 5.
The positive electrode plate 3 is formed by applying a positive electrode active material such as lithium manganate to both surfaces of a positive electrode metal foil such as aluminum and then punching it into a substantially rectangular shape. At the time of punching, the positive electrode metal foil not coated with the positive electrode active material is also punched integrally with the positive electrode plate 3, and the positive electrode metal foil becomes the positive electrode tab 14 connected to the positive electrode plate 3.
On the other hand, the negative electrode plate 4 is formed by coating a negative electrode active material such as carbon on both surfaces of a negative electrode metal foil such as copper and then punching it into a substantially rectangular shape. At the time of this punching, the negative electrode metal foil not coated with the negative electrode active material is also punched integrally with the negative electrode plate 4, and the negative electrode metal foil becomes the negative electrode tab 15 connected to the negative electrode plate 4. The dimension of the substantially rectangular shape in the XZ plane of the negative electrode plate 4 is a dimension that can be accommodated without bending inside the battery container, and the dimension of the substantially rectangular shape in the XZ plane of the positive electrode plate 3 is substantially rectangular in the XZ plane of the negative electrode plate 4. Is smaller than Therefore, as shown in FIG. 1A, the positive electrode plate 3 is disposed in the plane of the negative electrode plate 4 when viewed from the Y direction. The negative electrode tab 15 is disposed at a position that does not overlap the positive electrode tab 14 on the XZ plane when the positive electrode plate 3 and the negative electrode plate 4 are laminated in the Y direction as described later.
The separator 5 may be a resin separator or a ceramic separator as long as it can be used for a so-called battery. Here, the separator 5 is formed in a bag shape, and the size of the bag is designed so that the entire surface of the positive electrode plate 3 is accommodated in the bag and the positive electrode tab 14 protrudes from the inside of the bag to the outside.
Note that a state in which the entire surface of the electrode plate (positive electrode plate 3 or negative electrode plate 4) is accommodated in the bag-shaped separator and the electrode tab (positive electrode tab 14 or negative electrode tab 15) protrudes from the inside of the bag to the outside. This is called “inclusive”.

Then, lamination is started from the negative electrode plate 4 having a size larger than that of the positive electrode plate 3, the positive electrode plate 3 wrapped with the bag-like separator 5 is laminated on the negative electrode plate 4 (+ Y direction), and then the separator 5 The negative electrode plate 4 is laminated on the positive electrode plate 3 wrapped in (+ Y direction). At this time, the plurality of positive electrode plates 3 to be stacked are stacked such that the positions of the positive electrode tabs 14 connected thereto are aligned in the XZ plane. The plurality of negative electrode plates 4 to be stacked are stacked such that the positions of the negative electrode tabs 15 connected thereto are aligned in the XZ plane.
This is sequentially repeated, and finally, a laminated electrode body 6 is formed which includes a plurality of positive electrode plates 3 and a plurality of negative electrode plates 4 and in which the negative electrode plates 4 are disposed at both ends in the Y direction when the YZ plane is viewed from the X direction. .
Note that all the positive electrode tabs 14 aligned at substantially the same position as viewed from the Y direction are electrically connected to the positive electrode terminal 8 by riveting or welding. At this time, the positive electrode tab 14 may be directly connected to the positive electrode terminal 8, or a metal positive electrode lead may be interposed between the positive electrode tab 14 and the positive electrode terminal 8. Also, all the negative electrode tabs 15 aligned at substantially the same position as viewed from the Y direction are electrically connected to the negative electrode terminal 9 by riveting or welding. At this time, the negative electrode tab 15 may be directly connected to the negative electrode terminal 9, or a metal negative electrode lead may be interposed between the negative electrode tab 15 and the negative electrode terminal 9.

Next, the first auxiliary sheet 12 and the second auxiliary sheet 13 will be described. First, the first auxiliary sheet 12 will be described with reference to FIG. Since the first auxiliary sheets 12a and 12b, which are the above-described “squeezed portions”, have the same shape, the first auxiliary sheet 12a is representatively shown in FIG.
FIG. 2A is an XZ plane schematic diagram of the surface (hereinafter referred to as the first surface) of the first auxiliary sheet 12a on the wall surface side of the closest battery container. As shown in the figure, the first surface is substantially rectangular. Specifically, the width between the inner walls in the X direction on the XZ plane of the battery case 2 and the length of the inner wall of the battery case 2 smaller than the length in the Z direction and not less than the height in the Z direction of the laminated electrode body 6 are set. It is a substantially rectangular shape substantially provided.
Further, the first auxiliary sheet 12a is formed with a plurality of (9 in this case) groove-shaped recesses 16 extending in the Z direction from the −Z side end of the first surface to the + Z side end. These are formed at equal intervals. Here, as shown in the cross-sectional view along the line BB ′ of FIG. 2A shown in FIG. 2C, the shape of the recess 16 is a substantially rectangular shape. Since any shape may be used as long as it has a function as a passage that can be lifted by buoyancy from the −Z direction to the lid 7 side (+ Z direction), for example, a semicircular shape may be used.
Further, the first auxiliary sheet 12a penetrates from the first surface to the back surface (hereinafter referred to as the second surface) as shown in the cross-sectional view along the line CC 'in FIG. 2A shown in FIG. 2D. A plurality of through holes 17 are formed in the recess 16. Here, seven circular through-holes 17 in the XZ plane are formed in one concave portion 16, but the shape of the through-hole 17 is circular as long as the bubbles and the electrolyte can be passed smoothly. The number of through holes 17 formed in one recess 16 can be changed as appropriate.

The second surface of the first auxiliary sheet 12a has a “squeezing function” for bubbles, which will be described later. Therefore, as the first surface extends in the + Z direction from the −Z side end to the + Z side, The shape is designed so that the surface gradually approaches the first surface (hereinafter referred to as “squeezed shape”). The direction in which the second surface gradually approaches the first surface along the squeezed shape is referred to as “squeezing direction”.
In other words, the first auxiliary sheet 12a is designed to gradually reduce the dimension (thickness) in the Y direction as it proceeds in the “squeezing direction”. In the YZ sectional view of FIG. 2B, the shape of the second surface is a predetermined distance L (for example, 3 mm ≦ L) from the −Z side end of the first surface with respect to the first surface arranged in the Z direction. The shape is such that a straight line is drawn from the end portion separated in the + Y direction by ≦ 5 mm toward the first surface at an angle α (for example, 45 ° <α <90 °). Since the squeezed shape is not necessarily the straight line, the portion corresponding to the straight line may be a curved line, for example. However, since the electrode plate of the laminated electrode body 6 is in contact with the second surface, it is desirable to make the surface substantially uniform and smooth without any irregularities so as not to damage the electrode plate.

The second auxiliary sheet 13 has a substantially rectangular shape on the YZ plane of FIG. Specifically, the width between the inner walls in the Y direction on the YZ plane of the battery container 2 and the length of the inner wall of the battery container 2 that is smaller than the length in the Z direction and greater than the height in the Z direction of the laminated electrode body 6 are set. It has a substantially rectangular shape.
Unlike the first auxiliary sheet 12, the second auxiliary sheet 13 does not have a squeezed shape, but the other (excluding dimensions) has the same configuration as the first auxiliary sheet 12. Specifically, the second auxiliary sheet 13 includes two planes (front surface and back surface) substantially parallel to the YZ plane of FIG. 1, and a concave portion 16 is formed on one of the two planes (front surface). And a plurality of through holes corresponding to the through holes 17 are formed in the grooves. Since the front surface is disposed on the wall surface of the battery container and the back surface is directed toward the laminated electrode body, the electrode plate of the laminated electrode body 6 is in contact with the other surface (back surface) of the two planes. become. Therefore, it is desirable that the back surface be a substantially uniformly smooth surface without irregularities so as not to damage the electrode plate.

Now, the “squeezing function” will be described. As described above, the pair of first auxiliary sheets 12, the pair of second auxiliary sheets 13, and the laminated electrode body 6 are housed inside the battery container as one unit. Here, the two first auxiliary sheets 12 (12a and 12b) are the end surfaces on the −Y side, out of the two end surfaces of the stacked electrode body 6 existing in the stacking direction (Y direction) of the electrode plates of the stacked electrode body 6. The second surface of the first auxiliary sheet 12a is in contact with the end surface on the + Y side, and the second surface of the first auxiliary sheet 12b is in contact with the end surface on the + Y side. In addition, the two second auxiliary sheets 13 are two of the laminated electrode body 6 that is perpendicular to the laminating direction (Y direction) and in the direction in which the electrode tab protrudes from the electrode plate (+ Z direction) and the perpendicular direction (X direction). Of the two end surfaces, the rear surface of one second auxiliary sheet 13 is in contact with the end surface on the −X side, and the rear surface of the other second auxiliary sheet 13 is in contact with the end surface on the + X side.
When the battery 1 is charged and discharged, bubbles are generated due to decomposition or the like of the electrolytic solution or the electrolyte. Among these, fine bubbles generated in the laminated electrode body 6 are generated in the positive electrode plate 3 and the negative electrode plate 4. It adheres to the surface, that is, the electrode plate surface. When the battery 1 is arranged as shown in FIG. 1, the buoyancy of the bubbles acts in the + Z direction, which is the direction opposite to the gravity, from the bottom of the battery container toward the lid 7. It naturally rises up to the periphery of the lid 7 and accumulates here. However, some of the bubbles generated inside the laminated electrode body 6 are compressed by, for example, adjacent electrode plates and cannot naturally rise due to buoyancy, and as a result, the bubbles are attached to the surface of the electrode plate. May be maintained. Thus, if bubbles remain on the surface of the electrode plate, the electrode plate in contact with the bubbles cannot contribute to the movement of ions, which may reduce the battery performance.
Therefore, in order to prevent a reduction in the capacity of the battery, the battery 1 has a “squeezing function” by a squeezing unit. The “squeezing function” is a function that squeezes bubbles that adhere to the surface of the electrode plate, naturally or that cannot easily rise due to buoyancy, to the “squeezing direction” by the “squeezing shape” of the squeezing part, and the bubbles are covered. 7 is a function of floating up to the periphery of the battery 7, and positively utilizes the movement of the laminated electrode body 6 that expands and contracts in the lamination direction (Y direction) due to charging and discharging of the battery 1. This will be described in detail below.

Since the glue of the insulating tape used in forming the unit is altered in the electrolytic solution or the like, as a result, the insulating tape is loose in the battery container. For this reason, when the positive electrode active material and the negative electrode active material are the above-described secondary batteries, the negative electrode active of each negative electrode plate 4 of the laminated electrode body 6 is not substantially affected by the insulating tape when the battery 1 is charged. The material expands in the stacking direction (Y direction) by substantially the same amount at any position on the XZ plane.
Accordingly, when the amount of expansion increases as charging progresses, the pair of first auxiliary sheets 12 gradually move from the bottom of the battery container toward the lid 7, that is, from the −Z side to the + Z side, gradually on the respective second surfaces. Thus, the laminated electrode body 6 is contacted. At this time, if the first surfaces of the pair of first auxiliary sheets 12 are in contact with the wall surface of the battery container, it is no longer difficult for the first auxiliary sheet 12 to move in the Y direction as the laminated electrode body 6 expands.
For this reason, when the laminated electrode body 6 further expands in a state where the first surface of each first auxiliary sheet 12 is in contact with the wall surface of the battery container, the laminated electrode body 6 causes the second surface of the first auxiliary sheet 12 to expand. The pressure is sequentially applied from the bottom of the battery container toward the lid 7 (in the + Z direction). That is, the distance between the second surfaces of the two first auxiliary sheets 12 in the stacking direction (Y direction) is gradually wider from the bottom of the battery container toward the lid 7, in other words, the direction perpendicular to the direction in which the buoyancy of the bubbles works. In addition, since the distance between the “squeezed portions” inside the battery container in the stacking direction gradually increases toward the “squeezing direction”, the negative electrode active material of each negative electrode plate 4 of the stacked electrode body 6 is located at any position on the XZ plane. However, if the same width is to be expanded in the stacking direction (Y direction), the stacked electrode body 6 is gradually pressurized from the bottom of the battery container by its expansion force.
In other words, in the battery 1, the “squeezed shape” of the first auxiliary sheet 12, which is the “squeezed portion”, causes the pressure applied between the electrode plates of the laminated electrode body 6 in the direction from the bottom of the battery container toward the lid 7. A configuration in which the pressure gradually decreases and a configuration in which the value of the pressure gradually increases by the same amount at any location where the active material of the electrode plate is applied.
For this reason, the bubbles adhering to the electrode plate can be effectively squeezed out in the “squeezing direction”, and the bubbles can be lifted in the direction in which the buoyancy of the bubbles works.

With the above simple configuration, bubbles generated inside the laminated electrode body are lifted to promote removal of the bubbles from the inside, thereby providing a battery with improved battery performance.
In the above embodiment, only one laminated electrode body 6 is accommodated in the battery container. However, a plurality of laminated electrode bodies 6 (here, laminated electrode bodies 6a and 6b) are used as in the modification of FIG. Each of these may be unitized in the same manner as in FIG. 1 and stored in the battery container. However, in this case, it is desirable to unitize the laminated electrode body 6 so that each auxiliary sheet does not hinder the electrical connection between the electrode tabs 14 and 15 and the corresponding electrode terminals 8 and 9. For this reason, in FIG. 3, the laminated electrode body 6a is arranged corresponding to the first auxiliary sheet 12a and the first auxiliary sheet 12b of FIG. 1 and has a smaller dimension in the Z direction than the first auxiliary sheet 12b. Except for the above, the first auxiliary sheet 12b has the same configuration as the first auxiliary sheet 12b and is unitized. The laminated electrode body 6b is disposed corresponding to the first auxiliary sheet 12b and the first auxiliary sheet 12a in FIG. 1 and has a smaller dimension in the Z direction than the first auxiliary sheet 12a. It is united by being sandwiched between a first auxiliary sheet 12d having the same configuration as the sheet 12a.

Further, in the battery of FIG. 1 or FIG. 3, since the −Z direction is the gravitational direction, the reverse direction of the gravitational direction and the squeezing direction are substantially the same. However, for example, when the battery is placed sideways, the removal of bubbles generated inside the laminated electrode body can be promoted. That is, in the battery of FIG. 1 or FIG. 3, for example, the + X direction may be the gravity direction. In this case, the squeezing direction and the reverse direction of the gravity direction, which is the direction in which the buoyancy of the bubbles works, are not necessarily the same. It is possible to reduce the residence of the bubbles in the interior of the.

The present invention is not limited to the above-described embodiments and combinations thereof, and various modifications can be made without departing from the spirit of the present invention. For example, although the shape of the battery container has been described as a square shape, it may be a cylindrical shape. Similarly, the laminated electrode body 6 may be a laminated electrode body (stacked laminated electrode body) in which a plurality of positive electrode plates and a plurality of negative electrode plates are sequentially laminated via separators, or one positive electrode plate and 1 A laminated electrode body (rolled laminated electrode body) in which one negative electrode plate is laminated via one separator and wound may be used. In the case of a wound multilayer electrode body, the same effect as in the above embodiment can be obtained if the first auxiliary sheet 12 is configured to cover the periphery of the wound multilayer electrode body.
Further, although the battery container has been described as a conductive material, an insulating material such as a plastic resin may be used. Even when the battery container is formed of an insulating material, the first auxiliary sheet 12 or the second auxiliary sheet 13 functioning as an insertion guide is required to store the laminated electrode body 6 in the battery container without damage. Such auxiliary sheets are extremely useful.
Furthermore, when the function of the insertion guide is not important because the dimensions of the battery container are larger than the dimensions of the laminated electrode body 6, the first auxiliary sheet 12, which is a squeezing part, is provided when forming the battery container. A shape corresponding to the “squeezed shape” may be integrally formed with the same material using a mold or the like as the inner wall of the battery container. In this case, the inner wall itself becomes the squeezed portion. Of course, it may be formed separately from the battery container, like the first auxiliary sheet 12.
In addition, the first auxiliary sheet 12 and the second auxiliary sheet 13 may be made of the same material or different materials. Further, the first auxiliary sheet may be a plate-like sheet having a thickness and tension.

DESCRIPTION OF SYMBOLS 1 ... Battery, 2 ... Storage container, 3 ... Positive electrode plate, 4 ... Negative electrode plate, 5 ... Separator,
6 ... laminated electrode body, 7 ... lid, 8 ... positive electrode terminal, 9 ... negative electrode terminal,
10 ... Insulating resin, 11 ... Insulating resin plate,
12 (12a-12d) ... 1st auxiliary sheet, 13 ... 2nd auxiliary sheet,
14 ... positive electrode tab, 15 ... negative electrode tab,
16 ... recess (groove), 17 ... through hole,

Claims (5)

A laminated electrode body in which a first electrode plate and a second electrode plate are laminated via a separator;
An electrolyte or electrolyte;
A first electrode terminal electrically connected to the first electrode plate; and a second electrode terminal electrically connected to the second electrode plate; the electrolyte solution or the electrolyte and the laminated electrode body; A battery container that is hermetically sealed,
A battery having a squeezed portion formed integrally or separately with the battery container between the laminated electrode body and the battery container and gradually reducing its thickness as it advances in the squeezing direction. The squeezed portion is an insulating auxiliary sheet formed separately from the battery container,
2. It is promoted that bubbles generated inside the laminated electrode body are squeezed out in the squeezing direction and floated by a volume change of the laminated electrode body accompanying charging or discharging of the battery. The battery described in 1. The battery according to claim 2, wherein the auxiliary sheet includes a recess along a direction of gravity on a surface that can contact the battery container. The battery according to claim 3, wherein the auxiliary sheet includes a through-hole penetrating the auxiliary sheet in the recess. The squeezed portion is formed integrally with the battery container, and bubbles generated inside the laminated electrode body are squeezed out in the squeezing direction due to a volume change of the laminated electrode body accompanying charging or discharging of the battery. The battery according to claim 1, wherein the battery promotes floating.

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