JP2012009210A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress relative positional displacement of a positive electrode plate and a negative electrode plate to each other.SOLUTION: A battery includes: a substantially rectangular first electrode plate; an envelope-shaped separator containing the first electrode plate; a substantially rectangular second electrode plate laminated on the envelope-shaped separator; and protrusions formed on a surface of the envelope-shaped separator and protruding from the surface. The second electrode plate is held by the protrusions.

Description

  The present invention relates to a battery in which a positive electrode plate and a negative electrode plate are laminated via a separator.

As a battery that is practically used, there is a high-power lithium ion secondary battery. As a form of this lithium ion secondary battery, a laminated type in which a plurality of substantially rectangular positive electrode plates and negative electrode plates are laminated via a separator, and a pair of belt-like positive electrode plates and negative electrode plates are laminated via a separator. In general, the winding type is wound up after being wound (hereinafter, the positive electrode plate and the negative electrode plate are collectively referred to as “electrode plate”). The positive electrode plate and the negative electrode plate constituting these batteries are opposed to each other by applying a positive electrode active material and a negative electrode active material to a current collector such as an aluminum foil or a copper foil.
In these batteries, lithium ions are mainly exchanged between the surfaces facing each other, that is, between the surfaces of the negative electrode plate and the positive electrode plate that overlap each other in the stacking direction.

  By the way, in these batteries, the relative position of the laminated negative electrode plate and positive electrode plate may be shifted due to unexpected external force or the like when the battery is used. If the area of the portion where the active material coating surface of the positive electrode plate and the active material coating surface of the negative electrode plate overlap in the stacking direction due to the above-described misalignment, battery performance may be affected. . For this reason, conventionally, various techniques for suppressing the displacement of the relative position between the negative electrode plate and the positive electrode plate have been considered.

As one of such techniques, for example, there is a technique described in Patent Document 1 below.
In this technique, the positive electrode plate is processed into a wave shape to form a bent portion, and the negative electrode plate and the separator are processed into a wave shape in the same manner as the positive electrode plate to form a similar bent portion at a position corresponding to the bent portion of the positive electrode plate. To do. By aligning these bent portions with each other, deviation of the relative position of the separator with respect to the positive electrode plate and deviation of the relative position of the negative electrode plate with respect to the separator are suppressed.

JP 2009-129722 A

However, in the technique described in Patent Document 1, each electrode plate and separator are processed to form a bent portion. For example, when considering a positive electrode plate in which an active material is applied to a current collector, in order to form this active material in a wave shape, the active material is generally applied to a flat plate current collector and then wavy. Need to be processed.
When the current collector coated with the active material is processed into a wave shape, the active material is partially pulled and compressed where the convex portion and the concave portion are formed. There is a possibility that the active material is cracked or the active material or the like is partially separated from the electrode plate. And when an active material peels from an electrode plate, the electric capacity of a battery will fall by that much, and battery performance may fall as a result.

  The present invention has been made in order to solve the above-described problems, and the positive electrode can be used without performing the above-described wave processing that may cause cracking of the active material or separation of the active material from the current collector. An object of the present invention is to provide a high-performance battery as a result of suppressing the displacement of the relative position between the plate and the negative electrode plate.

  In order to solve the above problems, a battery of the present invention includes a substantially rectangular first electrode plate, a bag-like separator containing the first electrode plate, and a substantially rectangular second electrode laminated on the bag-like separator. It has a board and the convex part which is formed in the surface of the said bag-shaped separator, and protrudes from the said surface, Said 2nd electrode plate is hold | maintained at the said convex part, It is characterized by the above-mentioned.

  In the battery of the present invention, the first electrode plate is positioned by the bag-like separator, and the second electrode plate laminated on the separator is held by the convex portion formed on the surface of the bag-like separator, as a result. Deviation of the relative position between the first electrode plate and the second electrode plate can be suppressed.

  In the present invention, even when stacking misalignment occurs, one electrode plate (eg, positive electrode) disposed on the separator moves greatly relative to the other electrode plate (eg, negative electrode) contained in the separator. It suppresses that. Therefore, a high-performance battery can be provided.

It is a principal part notch perspective view of the battery of 1st embodiment which concerns on this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the positive electrode plate, negative electrode plate, and bag-shaped separator in the initial lamination | stacking arrangement | positioning of the battery of 1st embodiment which concerns on this invention, The figure (A) is these front views, The figure (B) is these. FIG. It is explanatory drawing which shows the formation method of the convex part in the battery of 1st embodiment which concerns on this invention. It is a figure which shows the 1st modification of the battery of 1st embodiment which concerns on this invention, The figure (A) is a front view of the positive electrode plate in the initial lamination | stacking arrangement | positioning, a negative electrode plate, and a bag-shaped separator, The figure (B) ) Is a side view of them. It is a 2nd modification of the battery of 1st embodiment which concerns on this invention, and is a front view of the positive electrode plate in the original lamination | stacking arrangement | positioning, a negative electrode plate, and a bag-shaped separator. It is a figure which shows the 3rd modification of the battery of 1st embodiment which concerns on this invention, The figure (A) is a front view of the positive electrode plate, negative electrode plate, and separator in an original lamination | stacking arrangement | positioning, The figure (B) is the figure. It is a deformation | transformation figure of the convex part 40c. It is a 4th modification of the battery of 1st embodiment which concerns on this invention, and is a front view of the positive electrode plate in the original lamination | stacking arrangement | positioning, a negative electrode plate, and a bag-shaped separator. It is a figure which shows the positive electrode plate, negative electrode plate, and bag-shaped separator in the initial lamination | stacking arrangement | positioning of the battery of 2nd embodiment which concerns on this invention, The figure (A) is these front views, The figure (B) is these. (C) is a side view of these. It is explanatory drawing which shows in detail the positional relationship of each convex part in the battery of 2nd embodiment which concerns on this invention. It is a figure which shows the 1st modification of the battery of 2nd embodiment which concerns on this invention, and the same figure (A) is a front view of the positive electrode plate in the original lamination | stacking arrangement | positioning, a negative electrode plate, and a bag-shaped separator, FIG. ) Is a rear view of these. It is a figure which shows the 2nd modification of the battery of 2nd embodiment which concerns on this invention, and the same figure (A) is a front view of the positive electrode plate, negative electrode plate, and bag-shaped separator in an original lamination | stacking arrangement | positioning, FIG. ) Is a rear view of these. It is explanatory drawing which shows in detail the positional relationship of each convex part in the 2nd modification of the battery of 2nd embodiment which concerns on this invention.

"First embodiment"
First, the battery according to the first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the battery according to the present embodiment includes a plurality of positive plates 10, a plurality of negative plates 20, and separators (here, each positive electrode plate 10 and each negative plate 20). A separator 30 that covers each of the plurality of negative electrode plates 20 in a bag shape), an electrolyte solution (not shown), and a battery can 90 that houses them.
In the following description, a lithium ion secondary battery will be described as an example, but the present invention is not limited to this. For example, the present invention can be applied to a battery in which a positive electrode plate and a negative electrode plate are stacked via a separator, such as a secondary battery other than a lithium ion secondary battery, or a primary battery.

The positive electrode plate 10 includes a positive electrode plate body 11 in which a positive electrode active material composed of, for example, a ternary material LiNixCoyMnzO2 (x + y + z = 1) is applied to a current collector obtained by processing an aluminum foil into a substantially rectangular shape. , And a positive electrode tab 19 extending from the end of the positive electrode plate body 11.
On the other hand, the negative electrode plate 20 includes a negative electrode plate body 21 in which a negative electrode active material composed of, for example, a carbon material (artificial graphite) is applied to a current collector obtained by processing a copper foil into a substantially rectangular shape, and the negative electrode plate 20. A negative electrode tab 29 extending from the end of the first electrode.
The positive electrode plate body 11 and the positive electrode tab 19 are integrally formed by punching with a punching die after the above-described positive electrode active material is applied to the positive electrode plate body 11. Similarly, the negative electrode plate main body 21 and the negative electrode tab 29 are also integrally formed by punching with a punching die after the above-described negative electrode active material is applied to the negative electrode plate main body 21. The positive electrode tab 19 and the negative electrode tab 29 are collectively referred to as an electrode tab.
The bag-like separator 30 is formed of a porous polyethylene resin, polyolefin resin, polyamide resin, or the like. The negative electrode plate body 21 of the negative electrode plate 20 is enclosed in a bag-like separator 30. A part of the negative electrode tab 29 is exposed from the separator 30.
The electrode laminate 100 is formed by laminating a plurality of the positive plates 10 and the separators 30 including the negative plates 20. Although not shown, the electrode plates at both ends of the electrode laminate 100 are the negative electrode plates 20 enclosed in the bag-like separator 30.

  The positive electrode tab 19 is electrically connected to a positive electrode terminal 91 fixed to one surface of the battery can 90 via a lead 93. On the other hand, the negative electrode tab 29 of the negative electrode plate 20 is electrically connected to the negative electrode terminal 92 fixed to the one surface of the battery can 90 via a lead 93.

2A and 2B, the relationship between the negative electrode plate 20 contained in the bag-like separator 30 and the positive electrode plate 10 laminated thereon, in other words, the original electrode plate and the bag-like separator laminated. The arrangement relationship between them, that is, the initial laminated arrangement is shown.
As shown in FIG. 2A, the positive electrode plate body 11 has a substantially rectangular shape. Here, of the four sides of the substantially rectangular shape, the side to which the positive electrode tab 19 is connected is the side 13b, and the side facing the side 13b is the side 13a (the side 13b is located above (+ Y direction) when viewed from the side 13a). The two sides connected to the end portions of the sides 13a and 13b are referred to as sides 14a and 14b (the side 14b is located on the right side (+ X direction) when viewed from the side 14a).
The positive electrode tab 19 is arranged so as to be biased toward the −X direction side from the midpoint of the side 13b. Although the positive electrode tab 19 is expressed as being connected to the side 13b for the sake of convenience, the positive electrode tab 19 is originally integrated with the current collector of the positive electrode plate body 11.

As shown in FIG. 2A, the negative electrode plate main body 21 also has a substantially rectangular shape (the portions included in the bag-shaped separator 30 are indicated by dotted lines). Here, of the four sides of the substantially rectangular shape, the side to which the negative electrode tab 29 is connected is the side 23b, and the side opposite to the side 23b is the side 23a (the side 23b is located above (+ Y direction) when viewed from the side 23a). The two sides connected to the respective end portions of the sides 23a and 23b are called sides 24a and 24b (the side 24b is located on the right side (+ X direction) when viewed from the side 24a).
The negative electrode tab 29 is arranged so as to be biased toward the + X direction side from the midpoint of the side 23b. For this reason, the positive electrode tab 19 and the negative electrode tab 29 do not overlap each other when viewed from the stacking direction (Z-axis direction), and a short circuit between the positive electrode tab 19 and the negative electrode tab 29 can be prevented. Although the negative electrode tab 29 is expressed as being connected to the side 23 b for convenience, the negative electrode tab 29 is originally integrated with the current collector of the negative electrode plate body 21.
In the initial stacking arrangement, the negative electrode plate body 21 is configured to have a slightly larger area than the positive electrode plate body 11, and the positive electrode plate body 11 is in the plane of the negative electrode plate body 21 when viewed from the stacking direction (Z-axis direction). Is placed and stacked so that

The bag-shaped separator 30 includes a first separator 31 having a substantially rectangular shape having a slightly larger area than the negative electrode plate main body 21 and a second separator 32 having substantially the same shape as the first separator 31. After sandwiching, the four sides of the first and second separators are fused with a heat sealer (melted by heat and then bonded by pressure).
As shown in FIG. 2A, the portions of the first and second separators adjacent to the side 23a of the negative electrode plate main body 21 are directly fused together to form a fused portion 35a, and the side 24a of the negative electrode plate main body 21 is formed. The first and second separator portions adjacent to each other are directly fused together to form a fused portion 36a, and the first and second separator portions adjacent to the side 24b of the negative electrode plate body 21 are directly fused to each other. The fused portion 36b is formed, and the portions of the first and second separators that are close to the side 23b of the negative electrode plate body 21 and do not overlap the negative electrode tab 29 are directly fused to each other to form the fused portion 35b. .
Here, a corresponding fused portion is locally formed near the midpoint of each side of the negative electrode plate body 21. In the figure, these fused portions are formed in a linear shape, but may be formed in a dotted shape.
A bag-shaped separator 30 is constituted by the first and second separators by these four fused portions. Since each of the four fused portions corresponds to the four sides of the negative electrode plate main body 21 and is disposed close to the negative electrode main body 21, the negative electrode plate main body 21 included in the bag-shaped separator 30 is attached to the bag-shaped separator 30. Will be positioned. In addition, since the first and second separators are not fused to each other except for the four fused portions, the electrolyte can be sufficiently permeated into the negative electrode plate body 21.

  In FIG. 2A, one fused portion corresponding to each side of the negative electrode plate main body 21 is formed. However, considering the certainty of the positioning and the degree of penetration of the electrolyte, A plurality of fused portions may be provided on each side. In FIG. 2A, one fused portion corresponding to each of all sides of the negative electrode plate body 21 is formed. However, a fused portion corresponding to the side where the negative electrode tab 29 is disposed is formed. Alternatively, a fusion separator corresponding to the other three sides may be provided to form a bag-shaped separator.

As shown in FIGS. 2 (A) and 2 (B), there are two portions on the first separator 31 in the vicinity of the fused portion 35a and not overlapping the surface of the negative electrode plate body 21 included in the separator 30. A convex portion 40 is formed. As described above, the positive electrode plate main body 11 in the initial laminated arrangement is arranged in the plane of the negative electrode plate main body 21, but the positive electrode plate main body 11 is displaced from the original laminated arrangement due to vibration or the like during battery use. This may occur and move downward (−Y direction) of the battery can 90. At this time, since the positive plate main body 11 is supported and held by these two convex portions 40, the relative positional deviation between the negative plate main body 21 and the positive plate main body 11 can be minimized.
In this way, in order to reliably support the positive electrode plate body 11 with the two convex portions 40, the two convex portions 40 are arranged with a certain interval therebetween. Specifically, the two convex portions 40 sandwich the fused portion 35a in the X-axis direction and are disposed at substantially the same position as the fused portion 35a in the Y-axis direction. Therefore, these convex portions are not formed in the plane of the negative electrode plate body 21 in the stacking direction. Of course, when a convex portion having a length corresponding to the certain interval can be formed, it is not necessary to form two convex portions, and only one convex portion is formed and the positive electrode plate body 11 is supported and held. It is also possible to do.
In addition, the height of the protrusion 40 in the stacking direction (Z-axis direction) of the negative electrode plate body 21 and the positive electrode plate body 11 is desirably a height that does not exceed the thickness of the stacked positive electrode plate body 11. This is because the laminated state is not affected.

  As shown in FIG. 3, the convex part 40 is formed using the tool T provided with a pair of clamping blades (the width of each clamping blade is t). Specifically, the surface of the electrode plate to be laminated is obtained by heating the pair of sandwiching blades to a temperature necessary for fusing and picking the projection forming position on the first separator 31 with the pair of sandwiching blades. Convex portions 40 are formed that project linearly (the distance from one end of the line to the other end is about t) and project in the stacking direction (Z-axis direction) when viewed from the direction (XY plane). In order to better support the positive electrode plate body 11, as shown in FIG. 3, one of the pair of sandwiching blades is in the + Y direction so that the linear portion is disposed substantially parallel to the side 23a of the negative electrode plate body 21. And the other operates in the −Y direction to sandwich the separator 30.

  Here, the convex portion 40 is formed on the separator 30 in a state where the negative electrode plate main body 21 is encapsulated in the separator 30, that is, in a state where the fused portion is formed. However, the present invention is not limited to this, and the fusion part may be formed after the convex part 40 is formed on the separator 30. Since the process of picking with the said clamping blade is required in order to form the convex part 40, time is required rather than pressing with a heat sealer and forming the said melt | fusion part. Therefore, if the convex portion 40 is formed in advance before the negative electrode plate main body 21 is sandwiched between the first and second separators, the thermal influence on the active material of the negative electrode plate main body 21 can be reduced.

  As described above, in the battery according to the present embodiment, the negative electrode plate body 21 is positioned by the four fused portions inside the bag-like separator 30, and the positive electrode plate body 11 is further below the battery can 90 due to vibration or the like. Even when a positional deviation occurs, the positive electrode plate body 11 is supported and held by one surface of the bag-like separator 30, that is, the two convex portions 40 formed on the first separator 31. It is possible to reduce as much as possible the area of the portions of the positive electrode plate body 11 that do not overlap each other in the stacking direction (Z-axis direction). Therefore, the battery performance can be prevented from being lowered and a high-performance battery can be provided.

In the battery of this embodiment, two separators are fused to form a bag, but a sheet-like separator is folded and fused to form a bag-like separator, and the four fusions described above. A landing part and two convex parts may be formed.
Further, in the battery of this embodiment, the negative electrode plate body is included in the bag-shaped separator. Similarly, instead of the negative electrode plate body, the positive electrode plate body is included in the bag-shaped separator and four fusion plates are used. It is good also as a structure which forms a contact part and forms two convex parts in the said separator, and supports and hold | maintains a negative electrode plate main body.
Further, not only the negative electrode plate main body but also the positive electrode plate main body is included in a bag-shaped separator, and the other bag-shaped separator is supported and held by two convex portions formed on one of the bag-shaped separators. It is good.
The number of convex portions may be at least two in order to support and hold the positive electrode plate body 11. Of course, if two or more convex portions are formed, the supporting and holding force can be strengthened.

<First modification>
A first modification of the battery according to the first embodiment will be described with reference to FIG. The following various modifications (first modification to fourth modification) are all different from the first embodiment in the position and number of convex portions formed on the bag-shaped separator 30. Other configurations are the same as those of the first embodiment.
In the first embodiment, two convex portions are formed only on one surface of the bag-shaped separator 30, that is, the first separator 31. However, in this modification, both surfaces of the bag-shaped separator 30, that is, the first separator 31. Two convex portions 40 are formed on the second separator 32, and two convex portions 40 a are also formed on the second separator 32. The height of the convex portion 40 a in the stacking direction is the same as the height of the convex portion 40.
Further, the two convex portions 40 and the two convex portions 40a are disposed at the same position as the fusion portion 35a in the Y-axis direction. Therefore, these convex portions are not formed in the plane of the negative electrode plate body 21 in the stacking direction.
Furthermore, although the two convex portions 40 and the two convex portions 40a are both arranged with the fusion portion 35a interposed therebetween, the positions in the X-axis direction are different from each other. Is done. Thus, since all four are arranged at different positions, the number of convex portions is twice that of the first embodiment, without affecting the laminated state of the electrode plates, compared to the first embodiment. The positive electrode plate body 11 can be supported and held more firmly. Therefore, it is possible to prevent a decrease in battery performance more effectively than in the first embodiment.

  In addition, when the positive electrode plate body 11 can be sufficiently supported and held by two convex portions, one convex portion 40 and one convex portion 40a may be arranged. In this case, it is desirable to arrange the fused portion 35a so as to be sandwiched between the convex portion 40 and the convex portion 40a when viewed from the stacking direction (Z-axis direction).

<Second modification>
A second modification of the battery according to the first embodiment will be described with reference to FIG.
In the first embodiment, the two convex portions 40 are formed in the vicinity of the fused portion 35a corresponding to the side opposite to the side of the negative electrode plate body 21 where the negative electrode tab 29 is formed. A convex portion similar to the convex portion 40 is formed not only in the portion 40 but also in the vicinity of each of the fused portions 35 b, 36 a, 36 b corresponding to the other sides of the negative electrode plate body 21.
Specifically, the two convex portions 41a sandwich the fused portion 36a from the Y-axis direction and are disposed at substantially the same position as the fused portion 36a in the X-axis direction. The two convex portions 41b sandwich the fused portion 36b in the Y-axis direction and are disposed at substantially the same position as the fused portion 36b in the X-axis direction. With this configuration, when the positive electrode plate 10 stacked on the negative electrode plate 20 via the bag-shaped separator 30 during the initial stacking is displaced in the left and right direction (X-axis direction) due to vibration or the like when the battery is used. Also, the positive plate body 11 is supported and held by the two convex portions 41a or the two convex portions 41b, so that they overlap each other in the stacking direction (Z-axis direction) of the negative plate body 21 and the positive plate body 11. The area of the non-existing portion can be reduced as much as possible.

  Furthermore, the two convex portions 40b are disposed at substantially the same position as the fusion portion 35b in the Y-axis direction. Unlike the convex portions 40, 41a and 41b formed corresponding to the other three sides, in FIG. 5, the two convex portions 40b are spaced apart from the fused portion 35b toward the negative electrode tab 29 side (+ X side). Is formed. This is for avoiding an influence on the lamination state due to the projection 40b hitting the positive electrode tab 19 of the positive electrode plate 10 in the original lamination arrangement in the lamination direction (Z-axis direction). When it can be designed so that the positive electrode tab 19 and the convex portion 40b do not hit in the stacking direction, the fusion portion 35b is sandwiched between the two convex portions 40b in the X-axis direction like the other three sides. May be. With this configuration, even when the positive electrode plate 10 in the initial stacked arrangement is displaced in the upward direction (+ Y direction) of the battery can due to vibration or the like when the battery is used, the positive electrode plate body 11 is supported by the two convex portions 40b. Therefore, it is possible to reduce the area of the portion of the negative electrode plate main body 21 and the positive electrode plate main body 11 that do not overlap each other in the stacking direction (Z-axis direction) as much as possible.

  Similar to the first embodiment, these convex portions are not formed in the plane of the negative electrode plate body 21 in the stacking direction. Further, the respective convex portions are formed such that the respective linear portions of the respective convex portions are arranged substantially parallel to the respective sides of the corresponding negative electrode plate main body 21.

In this modification, convex portions are formed only on one surface of the bag-shaped separator 30, that is, the first separator 31. However, as in the first modified example, convex portions 40, 40 b are formed on both surfaces of the bag-shaped separator 30. , 41a and 41b may be formed. However, since it is the same as that of the first modification, each of the corresponding protrusions is stacked with each of the protrusions 40, 40 b, 41 a, 41 b formed in the other separator 30 when stacked. (Z-axis direction) is arranged at a position that does not overlap with the convex portions 40, 40b, 41a, 41b formed on the other separator 30 on the XY plane so as not to hit.
Here, in order to hold the positive electrode plate 10 laminated on the negative electrode plate 20 and restrict movement in each direction, two convex portions are formed corresponding to each side of the negative electrode plate body. Without limitation to the above, one or three or more convex portions may be formed.

<Third modification>
A third modification of the battery according to the first embodiment will be described with reference to FIGS.
6A and 6B, unlike the convex portion 40b of the second modified example, the positive electrode tab 19 of the positive electrode plate 10 stacked on the negative electrode plate 20 via the bag-like separator 30 is sandwiched in this modified example. As described above, two convex portions 40 c are formed on the separator 30. The two convex portions 40c are arranged in the vicinity of the side 23b of the negative electrode plate main body 21 and substantially at the same position on the Y axis. Accordingly, two convex portions 41a and 41b that are formed in the second modification are respectively formed. Specifically, the convex portion 41a is formed only on the bottom surface side (−Y side) of the battery can from the fusion portion 36a, and the convex portion 41b is formed on the bottom surface side (−Y side of the battery can from the fusion portion 36b. Side) only. About another part, it is the same as that of a 2nd modification.
Thus, in this modification, since the positive electrode tab 19 of the positive electrode plate 10 laminated on the negative electrode plate 20 via the separator 30 is sandwiched between the two convex portions 40c, the positive electrode tab 19 with respect to the separator 30 has a structure. The relative movement in the ± X direction can be restricted. Therefore, even when the positive electrode plate 10 is displaced from the initial arrangement, the area of the portion of the negative electrode plate main body 21 and the positive electrode plate main body 11 that do not overlap each other in the stacking direction (Z-axis direction) is It can reduce more effectively than a modification.

In FIG. 6A, the linear portion of the convex portion 40c is arranged so as to be substantially parallel to the side 23b of the negative electrode plate main body 21, but in FIG. 6B, the linear portion. Is formed in parallel with the direction in which the positive electrode tab 19 extends (Y-axis direction). Compared to the structure of FIG. 6A, in the structure of FIG. 6B, in addition to the above effects, the movement of the positive electrode plate 10 in the rotational direction on the XY plane can also be effectively restricted.
In this modification, convex portions are formed only on one surface of the bag-shaped separator 30, but corresponding to the convex portions 40, 40 c, 41 a, 41 b on both surfaces of the bag-shaped separator 30, as in the first modified example. Protruding parts may be formed. However, since it is the same as that of the first modification, each of the corresponding protrusions is stacked with each of the protrusions 40, 40 c, 41 a, 41 b formed in the other separator 30 when stacked. (Z-axis direction) is arranged at a position that does not overlap with the convex portions 40, 40c, 41a, 41b formed on the other separator 30 on the XY plane so as not to hit.

<Fourth modification>
A fourth modification of the first embodiment will be described with reference to FIG.
In the first embodiment, the convex portion 40 is not formed in the plane of the negative electrode plate main body 21 when viewed from the stacking direction (Z-axis direction), but in this modification, unlike the convex portion 40 of the first embodiment, the negative electrode plate main body. A convex portion 42 similar to the convex portion 40 is formed in the plane of 21. Specifically, the two convex portions 42 are arranged at a certain interval in the X-axis direction, and are viewed from above the fusion portion 35a (+ Y direction) and in the stacking direction (Z-axis direction) in the Y-axis direction. And disposed in the plane of the negative electrode main body 21 and at a position that does not overlap the positive electrode plate 10 in the initial laminated arrangement as viewed from the lamination direction.
When the protrusions are interposed between the positive electrode plate body 11 and the negative electrode plate body 21 that are charged and discharged when viewed from the stacking direction, the battery performance is not substantially affected. You may form these convex parts in the surface of the negative electrode plate main body 21 seeing from the lamination direction like an example.
With this configuration, even when the positive electrode plate body 11 is displaced from the initial arrangement due to vibrations when the battery is used or the like, and moves downward (−Y direction) of the battery can 90, these two protrusions 42 are also provided. Thus, the positive electrode plate body 11 is supported and held in the plane of the negative electrode plate body 21, so that no non-overlapping portions are generated on the surfaces of the negative electrode plate body 21 and the positive electrode plate body 11 in the stacking direction (Z direction). Therefore, it may be possible to effectively prevent a decrease in battery performance, as compared with the first embodiment and the second to third modifications.
However, in the present modification, as described above, the convex portion 42 is formed in the plane of the negative electrode plate main body 21, and therefore, after the convex portion 42 is formed, the fusion portion is formed to enclose the negative electrode plate main body 21. It is desirable to form a bag-like separator 30. This is because adverse effects on the negative electrode plate main body 21 due to heat generated by fusion during the formation of the convex portions 42 can be avoided.

In addition, in this modification, although the structure which replaced the convex part 40 in 1st embodiment with the convex part 42 is shown, each convex part in the structure of a 2nd modification-a 3rd modification is set to the convex part of this modification. When the positive electrode plate 20 is formed so as to overlap with the positive electrode plate 10 laminated in the original arrangement as seen from the laminating direction (Z-axis direction) as in the portion 42, the laminated positive electrode plate 20 Not only when moving downward (−Y direction) of the battery can 90, but also when the position is shifted in any direction, the portions of the negative electrode plate body 21 and the positive electrode plate body 11 that do not overlap each other in the stacking direction. Therefore, it may be possible to more effectively prevent a decrease in battery performance and provide a high-performance battery.
Of course, if the battery performance is substantially affected by forming more than two protrusions in the plane, the number of protrusions formed in the plane is adjusted as appropriate. It may be limited to a number that does not cause a significant influence. At this time, the protrusions other than the protrusions formed in the plane may be appropriately disposed at the positions shown in the second to third modifications.

  The above first embodiment and its modification examples can be applied to both stacked and wound batteries.

<Second embodiment>
A battery according to a second embodiment of the present invention will be described with reference to FIGS.
In the first embodiment, the convex portion made of the separator 30 itself is formed with the separator 30 interposed therebetween. However, in this embodiment, the point of forming the convex portion made of a member (described later) different from the separator 30 is large. It is a different point. That is, in this embodiment, the convex part which protruded from the surface of the separator 30 is formed like 1st embodiment. Other members are the same as in the first embodiment. In the second embodiment and the first modification and the second modification of the second embodiment described later, the fused portions 35a, 35b, 36a, and 36b shown in the first embodiment are not shown for convenience. However, these fusion parts are also formed in these second embodiments and their modifications.

8A, 8B, and 8C show the relationship between the negative electrode plate 20 enclosed in the bag-shaped separator 30 and the positive electrode plate 10 laminated thereon.
On both surfaces of the separator 30, substantially rectangular parallelepiped convex parts 51, 52, 53, and 54 made of a member different from the separator 30 are formed. Here, it is assumed that all of the convex portions 51, 52, 53, and 54 have a length L and a width W when viewed from the stacking direction (Z-axis direction). The height in the stacking direction is H (the height that does not contact the stacked separators 30 adjacent to each other).
Specifically, as shown in FIGS. 8A and 8C, the surface of the first separator 31 (see FIG. 8C), which is substantially the same position as the fused portion 35a in the Y-axis direction. And the convex part 51 is arrange | positioned so that the said length L may become substantially parallel to a X-axis direction. Since the convex portion 51 is thus substantially at the same position as the fused portion 35a in the Y-axis direction, it is not formed in the plane of the negative electrode plate body 21 in the stacking direction.

As shown in detail in FIG. 9, when viewed in the XY plane of FIG. 8A, the position is substantially the same as the convex portion 51 on the Y axis and is more than the convex portion 51 on the X axis. The convex portion 53 is arranged at a position on the surface of the second separator 32 that is in the + X direction and does not overlap the convex portion 51 (see FIG. 8C). 8A, substantially the same position as the convex portion 53 on the X axis, and in the −Y direction from the convex portion 53 on the Y axis, and the convex portion. The convex part 52 is arrange | positioned in the position (refer FIG.8 (C)) of the surface of the 1st separator 31 which does not overlap 53. FIG. Further, when viewed in the XY plane of FIG. 8A, the position is the same as the convex portion 52 on the Y axis, and is in the −X direction on the X axis from the convex portion 52 and overlaps the convex portion 52. The convex part 54 is arrange | positioned in the position (refer FIG.8 (C)) of the surface of the 2nd separator 32 which does not become.
That is, the convex portion 51 and the convex portion 52 are disposed on the front surface of the bag-shaped separator 30, and the convex portion 53 and the convex portion 54 are disposed on the back surface of the bag-shaped separator 30.

When a plurality of negative electrode plates 20 and positive electrode plates 10 are stacked via the bag-shaped separator 30, as described in the first embodiment, the positive electrode is in the plane of the negative electrode plate body 21 when viewed from the stacking direction (Z-axis direction). The plate bodies 11 are arranged and stacked so as to be accommodated (similar to the first embodiment).
At this time, the adjacent bag-shaped separators 30 are arranged in front of each other when the front surface of one bag-shaped separator 30 and the back surface of the other bag-shaped separator 30 face each other. The convex portions 51 and 52 and the convex portions 53 and 54 arranged on the back surface do not overlap, but are stacked so as to fit and mesh with each other as shown in FIG.
With this configuration, even when the positive electrode plate 10 stacked in the initial stacked arrangement is displaced in the downward direction (−Y direction) of the battery can due to vibration or the like when the battery is used, the two adjacent bag-shaped separators In the positive electrode plate 10 interposed between 30, the two convex portions 51 and the convex portion 53 support and hold the positive electrode plate body 11. Therefore, it is possible to reduce as much as possible the area of the portion where the negative electrode plate body 21 and the positive electrode plate body 11 do not overlap with each other in the stacking direction (Z-axis direction).
Further, according to this configuration, the adjacent bag-shaped separators 30 are stacked so as to be engaged with each other by the convex portions arranged two each as described above. The positional deviation between the separators 30 can be reduced as much as possible. The closer the convex portions on the front and back sides are arranged, the more the meshing effect is increased, and the positional deviation can be effectively prevented.
Similar to the first embodiment, the negative electrode plate body 21 is positioned in the bag-shaped separator 30. Therefore, in the stacked battery, the positional deviation between the plurality of negative electrode plate bodies 21 is prevented, and the positive electrode plate body stacked between them is also held by the two convex portions as described above, so that a decrease in battery performance is suppressed, A high-performance battery can be provided.

Here, the other member forming the convex portions 51 to 54 may be a resin or the like similar to the material of the separator 30. In this case, the resin or the like is appropriately molded and glued or melted on the surface of the separator 30. The convex portions 51 to 54 are formed.
From the viewpoint of industrially easier manufacture, it is desirable to use ceramics such as aluminum oxide or aluminum nitride as the separate member rather than the resin or the like. Examples of a method for forming the convex portion on the surface of the separator 30 with these materials include various methods such as an easy-to-form masking method and a printing method.
In the masking method, first, a mask pattern in which through holes corresponding to the shapes and sizes of the convex portions 51 to 54 are formed is prepared. Next, a solvent is mixed with the ceramic powder to form a slurry. Then, this mask pattern is placed on the separator, the slurry is coated on the separator, and the mask pattern is removed after the slurry is dried. Thus, the convex portions 51 to 54 made of ceramics are formed on the separator.
In the printing method, a slurry containing ceramic powder and a solvent is attached to a separator using a printing technique, and then the slurry is dried. Also by the above method, the convex parts 51-54 by ceramics can be formed on a separator.
Therefore, as compared with the first embodiment, the formation position of the convex portion on the separator 30 can be easily adjusted, and the height of the convex portion can be adjusted more easily.

In the present embodiment, two convex portions are formed on the front surface and the rear surface of the bag-shaped separator 30, and the convex portions of the adjacent bag-shaped separators 30 are engaged with each other as shown in FIG. In addition, not only can the positive and negative electrode plates 11 be supported and held more firmly when the front and back surfaces of the bag-shaped separator 30 are formed in a zigzag manner and meshed with each other. It is possible to prevent misalignment between the plurality of negative electrode plate bodies 21 firmly.
As described above, the meshing effect can be increased as the convex portions on the front surface and the back surface are arranged closer to each other. In this regard, if the above-described ceramics such as aluminum oxide and aluminum nitride are used as separate members, fine arrangement can be easily performed by a masking method, a printing method, or the like, which is suitable for the close arrangement.
In the battery of this embodiment, the negative electrode plate body is included in the bag-shaped separator. Similarly, the positive electrode plate body may be included in the bag-shaped separator instead of the negative electrode plate body. .
Furthermore, not only the negative electrode plate main body but also the positive electrode plate main body may be included in a bag-shaped separator, and similar convex portions may be formed in any bag-shaped separator so as to mesh with each other as described above.

<First modification>
A first modification of the battery of the second embodiment will be described with reference to FIG. In addition, all of the following various modified examples (first modified example to second modified example) are different from the second embodiment in the position and number of convex portions formed on the bag-shaped separator 30. Other configurations are the same as those of the second embodiment.
In the second embodiment, in each of the front and back surfaces of the bag-shaped separator 30, two protrusions are provided in the vicinity of the fusion portion 35 a corresponding to the side opposite to the side of the negative electrode plate body 21 where the negative electrode tab 29 is formed. In the present modification, not only these convex portions, but also the fusion portions 35b, 36a, 36b corresponding to the other sides of the negative electrode plate body 21 on the front surface of the bag-shaped separator 30 are provided. Convex portions similar to the convex portions 51 to 54 are formed in the vicinity or directly above. These convex portions 51 to 54 are not formed in the plane of the negative electrode plate main body 21 in the stacking direction.
With this configuration, even when the positive electrode plate 10 stacked in the initial stacked arrangement is displaced in the left-right direction (X direction) due to vibration or the like when the battery is used, the positive electrode plate main body at the convex portion 55a or the convex portion 55b. 11 is supported and held, the area of the portion of the negative electrode plate body 21 and the positive electrode plate body 11 that do not overlap each other in the stacking direction (Z direction) can be reduced as much as possible. In addition, with this configuration, the positive plate 10 is stacked at the convex portion 56 even when the positive plate 10 stacked in the initial stacked arrangement is displaced in the upward direction (+ Y direction) of the battery can due to vibration or the like when the battery is used. 11 is supported and held, the area of the portion of the negative electrode plate body 21 and the positive electrode plate body 11 that do not overlap each other in the stacking direction (Z direction) can be reduced as much as possible.

<Second modification>
A second modification of the battery according to the second embodiment will be described with reference to FIGS. 11 and 12.
Unlike the above-described meshing at one location in the vicinity of the fused portion 35a by the convex portions 51 to 54 in the battery of the second embodiment, each corresponds to two adjacent sides of the negative electrode body 21 contained in the bag-shaped separator 30. In the vicinity of the fused portion, two convex portions are arranged on the front and back surfaces of the bag-shaped separator 30 (four convex portions are arranged on each of the front and back surfaces of the bag-shaped separator). And it is set as the structure which meshes | engages in two places. Here, as in the second embodiment, each of these convex portions has a length L and a width W when viewed from the stacking direction, and the height in the stacking direction (Z direction) is H (adjacent to the stacked layers). It is assumed that it is a substantially rectangular parallelepiped having a height that does not contact the separator 30.

Specifically, as shown in FIG. 11A and FIG. 12 which is an enlarged view thereof, it is the surface of the first separator 31 (here, the front surface), which is substantially the same as the fused portion 35a in the Y-axis direction. The convex portions 51a and 52a are arranged at a certain interval so as to sandwich the fused portion 35a in the X-axis direction so that the position and the length L are substantially parallel to the Y-axis direction. Moreover, it is the surface (front here) of the 1st separator 31, Comprising: The convex parts 51b and 52b so that the said position L and the said length L may become substantially parallel to a X-axis direction substantially the same position as the melt | fusion part 36b. Are arranged at regular intervals so as to sandwich the fused part 36b in the Y-axis direction. These convex portions are not formed in the plane of the negative electrode plate body 21 in the stacking direction.
Further, as shown in FIG. 11B (and FIG. 12), it is the surface of the first separator 31 (here, the back surface), the position substantially the same as the fused portion 35a in the Y-axis direction, and the length described above. The convex portions 53a and 54a are arranged at a predetermined interval so as to sandwich the fused portion 35a in the X-axis direction so that L is substantially parallel to the Y-axis direction. At this time, the convex portions 53a and 54a are not overlapped with the convex portions 51a and 52a, and viewed from the stacking direction (Z-axis direction), and in a straight line connecting the convex portions 51a and the convex portions 52a. It arrange | positions in the position pinched | interposed with the convex part 52a. Further, on the front surface (here, the back surface) of the first separator 31, the convex portions 53b and 54b so that the position L is substantially the same as the fused portion 36b in the X-axis direction and the length L is substantially parallel to the X-axis direction. Are arranged at regular intervals so as to sandwich the fused part 36b in the Y-axis direction. At this time, the protrusions 53b and 54b are not overlapped with the protrusions 51b and 52b and are formed in a straight line connecting the protrusions 51b and 52b when viewed from the stacking direction (Z-axis direction). It arrange | positions in the position pinched | interposed with the convex part 52b.
These convex portions 51a, 52a, 53a, 54a, 51b, 52b, 53b, 54b are not formed in the plane of the negative electrode plate body 21 in the stacking direction.

With this configuration, even when the positive electrode plate 10 stacked in the initial stacked arrangement is displaced in the downward direction (−Y direction) of the battery can due to vibration or the like when the battery is used, the two adjacent bag-shaped separators Concerning the positive electrode plate 10 interposed between 30, the convex portions 51 a, 52 a, 53 a, 54 a support and hold the positive electrode plate body 11. Therefore, it is possible to reduce as much as possible the area of the portion where the negative electrode plate body 21 and the positive electrode plate body 11 do not overlap with each other in the stacking direction (Z-axis direction).
Further, according to this configuration, the adjacent bag-shaped separators 30 are engaged with each other at two positions, that is, the engagement between the projections 51a and 52a and the projections 53a and 54a in the X-axis direction, and the projection 51b in the Y-axis direction. , 52b and the convex portions 53b, 54b are laminated so that the positional deviation between the separators 30 can be reduced as much as possible by the above-described vibration or the like.
Note that the closer the convex portions on the front and the back are arranged, the greater the effect of the meshing and the more effectively preventing the positional deviation. Therefore, these convex portions are made of aluminum oxide or nitride as a separate member. It is desirable to use ceramics such as aluminum or the like and finely process it by a masking method or a printing method.
Similar to the second embodiment, the negative electrode plate body 21 is positioned in the bag-shaped separator 30. Accordingly, in the stacked battery, the positional deviation between the plurality of negative electrode plate bodies 21 is prevented, and the positive electrode plate main body stacked between them is also held by the convex portions as described above, so that the deterioration of the battery performance is suppressed, and the high performance Batteries can be provided.

  In this modification, it is configured to mesh at two locations as described above, but the convex portions having the same arrangement and configuration as the convex portions 51a, 52a, 53a, 54a are formed in the vicinity of the fusion portion 35b. Further, convex portions having the same arrangement and configuration as the convex portions 51b, 52b, 53b, 54b are formed in the vicinity of the fusion portion 36a, and are respectively formed on all sides of the negative electrode plate body 21 enclosed in the bag-shaped separator 30. It is good also as a structure which meshes | engages in the vicinity of the corresponding melt | fusion part, ie, four places. By so doing, it is possible to more effectively suppress a decrease in battery performance and provide a high-performance battery.

  In the second embodiment and its modification, none of the convex portions is formed in the plane of the negative electrode plate body 21 in the stacking direction. However, if the convex material is made of a porous material, for example, ceramics such as aluminum oxide or aluminum nitride, ion conductivity can be secured. Therefore, even if it is formed in the plane of the negative electrode plate body 21 as viewed from the stacking direction. Good. In this way, a portion that does not overlap with each other in the stacking direction (Z-axis direction) of the negative electrode plate main body 21 and the positive electrode plate main body 11 does not occur, and therefore it is possible to provide a higher performance battery. .

  The above second embodiment and its modifications are applicable to a stacked battery.

In the above first embodiment and its modification, the convex portion is formed by protruding the bag-shaped separator itself, but as in the second embodiment, the convex portion of the first embodiment and its modification is formed by a separate member. May be.
Further, in the second embodiment and the modified example thereof, the convex portion is formed of a different member different from the bag-shaped separator 30. However, as in the first embodiment, the convex portion of the second embodiment and the modified example is formed in a bag shape. The separator itself may be formed to protrude.

  In the first embodiment, the second embodiment, and modifications thereof, after forming a bag-like separator 30 containing the first electrode plate (for example, the negative electrode plate 20), the surface of the bag-like separator 30 is Two electrode plates (for example, positive electrode plate 10) were laminated. However, when applied to a stacked battery, the second separator 32, the negative electrode plate 20, and the first separator 31 are formed on the first separator 31 or the second separator 32 after forming a protruding portion protruding from the surface thereof. And stacking a plurality of units in which the positive electrode plate 10 is sequentially stacked in this order, and after the stacking, the plurality of stacked first and second separators are fused together to form a fused portion. It is good also as a bag-shaped separator with which several 1st and several 2nd separators were mutually connected. In other words, a plurality of bag-like separators 30 may be connected to each other at their fused portions. In this case, the same effect as described above can be obtained.

  The technical scope of the present invention is not limited to the above-described embodiments and their modifications. That is, various modifications can be made without departing from the gist of the present invention.

10: positive electrode plate, 11: positive electrode plate main body, 19: positive electrode tab, 20: negative electrode plate, 21: negative electrode plate main body, 29: negative electrode tab, 30: bag-shaped separator, 31: first separator, 32: second separator 40, 40a, 40b, 41a, 41b, 40c, 42, 55a, 55b, 56: convex portion

Claims (6)

A substantially rectangular first electrode plate;
A bag-like separator containing the first electrode plate;
A substantially rectangular second electrode plate laminated on the bag-shaped separator;
Formed on the surface of the bag-shaped separator, and having a protrusion protruding from the surface;
The battery, wherein the second electrode plate is held by the convex portion.   2. The battery according to claim 1, comprising a plurality of the convex portions, wherein the second electrode plate is held by at least two of the convex portions. A plurality of the first electrode plates;
The bag-shaped separator is composed of a first bag-shaped separator and a second bag-shaped separator each including one of the plurality of first electrode plates and provided with at least two convex portions.
The second electrode plate is sandwiched and stacked between the first bag-shaped separator and the second bag-shaped separator,
The first bag-shaped separator and the second bag-shaped separator are held by the one convex portion of the first bag-shaped separator and the one convex portion of the second bag-shaped separator. The battery according to claim 2, wherein each of the two convex portions is arranged so as to mesh with each other.   The battery according to claim 3, wherein the first electrode plate is a negative electrode plate, and the second electrode plate is a positive electrode plate.   The battery according to claim 4, wherein the convex portion is a protrusion of the bag-like separator itself.   The battery according to claim 4, wherein the convex portion is a separate member from the bag-shaped separator.

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