Battery and method for manufacturing the same

Abstract

To obtain a battery that can improve the ease of assembly between the outer casing and the lid, and a method for manufacturing the battery. [Solution] The battery 10 comprises an outer casing 20 having a rectangular flat bottom wall 22 and a pair of main body walls 24 integrally erected on the long sides of the bottom wall 22, and each of the pair of main body walls 24 having protruding portions 26 that extend toward each other at the ends opposite to the bottom wall 22, an electrode body 12 housed in the outer casing 20, and a lid 30 formed in a "convex" shape having a narrow portion 32 and a wide portion 34 in a cross-sectional view taken from a direction along the long side of the bottom wall 22, and provided so that the narrow portion 32 is sandwiched between the protruding portions 26.

Description

Technical Field

[0001] The present invention relates to a battery and a method for manufacturing the same.

Background Art

[0002] A sealed battery in which a lid is welded to an opening at the top of a battery can has been conventionally known (see, for example, Patent Document 1). This sealed battery has a portion extending beyond the upper part of the lid at the tip of the long side at the open end of the battery can. When the lid is fitted to the open end, after bending the portion extending beyond the upper part of the lid inward, it is sealed by welding.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, with the above configuration, unevenness (step portion) is formed between the bent portion of the battery can as the exterior body and the lid, and thus there is a risk that the sealing is impaired due to the unevenness (step portion). That is, with the above configuration, problems may occur after assembling the exterior body and the lid, and it is difficult to say that the assembling property is good. Further, when cooling the battery by bringing a cooling member into contact with the lid, it is difficult to bring the cooling member into contact with the lid due to such unevenness (step portion).

[0005] Therefore, an object of the present invention is to obtain a battery capable of improving the assembling property between an exterior body and a lid, and a method for manufacturing the battery.

Means for Solving the Problems

[0006] To achieve the above objective, a battery according to a first embodiment of the present invention comprises an outer casing having a rectangular flat bottom wall, a pair of main body walls integrally erected on the long side of the bottom wall, and each of the pair of main body walls having an overhang that extends toward each other at the end opposite to the bottom wall, an electrode body housed in the outer casing, and a lid which is formed in a "convex" shape having a narrow part and a wide part in a cross-sectional view taken from a direction along the long side of the bottom wall, and is provided such that the narrow part is sandwiched between the overhangs.

[0007] According to the first embodiment of the invention, the outer casing for housing the electrode body has a rectangular flat bottom wall and a pair of main body walls integrally erected on the long sides of the bottom wall, and each of the pair of main body walls has an overhang at the end opposite to the bottom wall that extends toward each other. A lid, formed in a "convex" shape with a narrow part and a wide part in a cross-sectional view along the long side of the bottom wall of the outer casing, is provided such that the narrow part is sandwiched between the overhangs of the outer casing. Therefore, the assembly of the outer casing to the lid becomes stronger, and the strength of the assembly part is improved. In other words, the ease of assembly between the outer casing and the lid is improved.

[0008] Furthermore, a battery according to a second embodiment of the present invention is a battery according to the first embodiment, wherein the outer surface of the narrow portion and the outer surface of the protruding portion are flush with each other.

[0009] According to the second embodiment of the invention, the outer surface of the narrow portion and the outer surface of the protruding portion are flush. Therefore, compared to, for example, the case where the outer surface of the protruding portion protrudes more than the outer surface of the narrow portion, there is no risk of impairing the assembly of the exterior body to the lid. In addition, when cooling the battery by bringing a cooling member into contact with the lid, it is easier to bring the cooling member into contact with the lid.

[0010] Furthermore, a third embodiment of the present invention is a battery according to the first or second embodiment, wherein the overhang length of the overhang portion in the approaching direction is the same.

[0011] According to the third embodiment of the invention, the overhang lengths of the protruding portions in the direction toward each other are the same. Therefore, compared to the case where the overhang lengths of the protruding portions in the direction toward each other are not the same, the assembly of the outer casing to the lid becomes even more robust, and the ease of assembly between the outer casing and the lid is further improved.

[0012] Furthermore, the fourth embodiment of the present invention is a battery according to any one of the first to third embodiments, wherein the thickness of the wide portion is greater than the thickness of the narrow portion.

[0013] According to the fourth embodiment of the invention, the thickness of the wide portion is greater than the thickness of the narrow portion. Therefore, even if the thickness of the outer casing is thin, damage to the electrode body is prevented when welding the cover to the outer casing.

[0014] Furthermore, a fifth embodiment of the present invention is a battery according to any one of the first to fourth embodiments, wherein the electrode body has a terminal portion capable of closing the opening of the outer casing on the short side of the bottom wall.

[0015] According to the fifth embodiment of the invention, the electrode body has a terminal portion that can close the opening of the outer casing on the short side of the bottom wall. Therefore, the opening of the outer casing can be closed simply by inserting the electrode body into the outer casing, and as a result, the lid becomes easier to assemble to the outer casing. In other words, the ease of assembly between the outer casing and the lid is improved.

[0016] Furthermore, a battery manufacturing method according to a sixth aspect of the present invention is a battery manufacturing method according to any one of the first to fifth aspects, comprising: an opening step of moving the protruding portions of the outer casing in a direction that separates them from each other to widen the end; an electrode insertion step of inserting an electrode into the outer casing whose end has been widened; a lid insertion step of inserting a lid into the end of the outer casing into which the electrode has been inserted; and a sealing step of moving the protruding portions in a direction that brings them closer together to clamp the narrow portion of the lid with the protruding portions, thereby sealing the end of the outer casing.

[0017] According to the invention of the sixth aspect, the overhanging portions of the exterior body are moved in a direction separating from each other to widen the ends on the side opposite to the bottom wall of the pair of main body walls, an electrode body is inserted into the exterior body with its ends widened, and a lid body is inserted into the above-mentioned ends of the exterior body with the electrode body inserted therein. Then, the overhanging portions are moved in a direction approaching each other to sandwich the narrow-width portion of the lid body with the overhanging portions, thereby sealing the above-mentioned ends of the exterior body. Therefore, the assembly of the exterior body to the lid body becomes firm, and the strength of the assembled portion is improved. That is, the assembling property between the exterior body and the lid body is improved.

Effects of the Invention

[0018] As described above, according to the present invention, the assembling property between the exterior body and the lid body can be improved.

Brief Description of the Drawings

[0019] [Figure 1] It is a schematic perspective view showing the battery according to the present embodiment. [Figure 2] It is a schematic perspective view showing the electrode body of the battery according to the present embodiment. [Figure 3] It is a schematic perspective view showing the exterior body of the battery according to the present embodiment. [Figure 4] It is a schematic perspective view showing the lid body of the battery according to the present embodiment. [Figure 5] It is a schematic cross-sectional view showing the internal structure of the battery according to the present embodiment. [Figure 6] (A) to (E) are schematic process diagrams showing the manufacturing method of the battery according to the present embodiment.

Modes for Carrying Out the Invention

[0020] Hereinafter, embodiments according to the present invention will be described in detail based on the drawings. For convenience of explanation, in each figure, the arrow UP shown as appropriate is the upward direction of the battery, the arrow FR is the front direction of the battery, and the arrow LH is the left direction of the battery. Therefore, in the following description, when the directions of up and down, front and back, and left and right are described without particular mention, they indicate up and down, front and back, and left and right in the battery, but are not particularly limited to these directions.

[0021] As shown in FIG. 1, the battery 10 according to the present embodiment is a all-solid-state battery, and includes an electrode body 12 shown in FIG. 2, an exterior body 20 shown in FIG. 3 that houses the electrode body 12, and a lid body 30 shown in FIG. 4 that closes the upper end portion (the end portion on the side opposite to the bottom wall 22 described later) of the exterior body 20 that houses the electrode body 12. The exterior body 20 and the lid body 30 are formed of a metal such as an aluminum alloy.

[0022] As shown in FIG. 2, the electrode body 12 is formed in a rectangular flat plate shape with the front-rear direction as the thickness direction. Metal terminal portions 14 are respectively attached to the left and right side portions of the electrode body 12 in advance by welding or the like. The terminal portion 14 is formed to be slightly larger than the left and right side portions of the electrode body 12, and has a size that can close the opening 18 described later of the exterior body 20. On the outer surface of the terminal portion 14, a pair of electrode terminals 16 having a substantially square shape and a predetermined protruding height as viewed from the left-right direction are integrally formed at a predetermined interval in the up-down direction.

[0023] As shown in FIG. 3, the exterior body 20 has a rectangular flat plate-shaped bottom wall 22 with the left-right direction as the longitudinal direction, and a pair of main body walls 24 that are integrally erected on the long side portions of the bottom wall 22, respectively. The short side portion side of the bottom wall 22 in the exterior body 20 is the opening 18. And on the upper end portions (the end portions on the side opposite to the bottom wall 22) of the pair of main body walls 24, overhang portions 26 that project in directions approaching each other are integrally formed.

[0024] Here, the overhanging length L (see FIG. 5) of the overhang portions 26 in the directions approaching each other is the same. That is, the narrow portion 32 described later of the lid body 30 that seals the upper end portion of the exterior body 20 is configured to be disposed at the center in the front-rear direction of the upper end portion. Also, as shown in FIG. 5, a heat conduction sheet 28 formed of a silicone-based resin material with a predetermined thickness is provided on the inner surface (upper surface) of the bottom wall 22 of the exterior body 20 over substantially the entire surface by being pasted.

[0025] As shown in Figure 4, the lid 30 is formed in a "convex" shape with a narrow section 32 and a wide section 34 at the top and bottom when viewed in cross-section from a direction along the long side of the bottom wall 22 of the outer casing 20. As shown in Figure 5, the width of the wide section 34 that constitutes the lower part of the lid 30 in the front-to-back direction is the same as the distance between the pair of main body walls 24, and the narrow section 32 that constitutes the upper part of the lid 30 is formed in the center of the wide section 34 in the width direction (front-to-back direction).

[0026] In other words, half the difference between the width of the wide section 34 and the width of the narrow section 32 is the same as the overhang length L of the overhang section 26, and when the lid 30 is installed on the upper end of the outer casing 20 (between the upper ends of the pair of main body walls 24), its narrow section 32 is sandwiched from the front and rear by the overhang section 26 (see Figure 5).

[0027] In other words, the opposing end faces 26A (see Figure 3) of each protruding portion 26 abut against the front-to-back oriented side surface 32A (see Figure 4) of the narrow portion 32, and the protruding portions 26 fit into the stepped portion 36 formed by the narrow portion 32 and the wide portion 34. In this state, the lid 30 is joined to the upper end of the outer casing 20 by welding, thereby sealing the upper end.

[0028] Furthermore, the upper surface (outer surface) of the narrow section 32 and the upper surface (outer surface) of the protruding section 26 are flush with each other (see Figure 5). That is, the thickness (height) H1 of the narrow section 32 is the same as the plate thickness of the protruding section 26 (exterior body 20). Also, the thickness (height) H2 of the wide section 34 is formed to be thicker than the thickness H1 of the narrow section 32 (H2 > H1). In addition, as shown in Figure 5, a heat conductive sheet 38 made of a silicone-based resin material and formed to a predetermined thickness is attached to almost the entire surface of the lower surface (inner surface of the lid 30) of the wide section 34.

[0029] The operation (manufacturing method) of the battery 10 according to this embodiment, which has the configuration described above, will now be explained.

[0030] First, as shown in Figure 6(A), a heat conductive sheet 28 is attached to the inner surface of the bottom wall 22 of the outer casing 20. Then, as shown in Figure 6(B), the protruding portions 26 of the outer casing 20 are moved in a direction that separates them from each other to widen the upper end of the outer casing 20 (opening process), and the electrode body 12 is inserted into the widened upper end of the outer casing 20 from above (electrode body insertion process). Figure 6(C) shows the state in which the electrode body 12 has been inserted (housed) in the outer casing 20.

[0031] Next, as shown in Figure 6(D), the lid 30 is inserted into the upper end of the outer casing 20 in which the electrode body 12 is inserted (housed) (lid insertion step). A heat conductive sheet 38 is attached to the lower surface of the wide portion 34 of the lid 30 in advance. Although not shown in the illustration, at this time as well, as shown in Figure 6(B), the protruding portions 26 of the outer casing 20 are moved in a direction that separates them from each other to widen the upper end of the outer casing 20 and insert the lid 30.

[0032] Once the lid 30 is inserted onto the upper end of the outer casing 20 (above the electrode body 12), the protruding portions 26 are moved toward each other, as shown in Figure 6(E), to clamp the narrow portion 32 of the lid 30 with the protruding portions 26, thereby sealing the upper end of the outer casing 20 (sealing process). That is, with the end faces 26A (see Figure 3) of each protruding portion 26 in contact with each side surface 32A (see Figure 4) of the narrow portion 32, the lid 30 is joined (sealed) to the upper end of the outer casing 20 by welding.

[0033] At this time, the terminal portions 14 (see Figures 1 and 2) provided on both the left and right sides of the electrode body 12 are also joined by welding to the left and right edges of the bottom wall 22 and the main body wall 24, and to the left and right ends of the lid 30, so as to seal the opening 18 of the outer casing 20. This results in the production of a battery 10 as shown in Figure 1.

[0034] With this type of battery 10, the assembly of the outer casing 20 to the lid 30 becomes more robust, improving the strength of the assembly. In other words, the ease of assembly between the outer casing 20 and the lid 30 can be improved.

[0035] Furthermore, since the upper surface of the narrow portion 32 of the lid 30 and the upper surface of the protruding portion 26 of the outer casing 20 are flush, there is no risk that the assembly of the outer casing 20 to the lid 30 will be impaired due to the protruding portion (not shown) causing a force to be applied to the protruding portion (the portion not shown) to separate it from the other.

[0036] Furthermore, if the upper surface of the narrow portion 32 of the lid 30 and the upper surface of the protruding portion 26 of the outer casing 20 are flush, it becomes easier to bring a cooling member (not shown) into contact with the lid 30 to cool (dissipate heat from) the battery 10. Therefore, the battery 10 can be cooled efficiently.

[0037] Furthermore, since this battery 10 is configured to hold the electrode body 12 between a heat conductive sheet 28 provided on the inner surface of the bottom wall 22 of the outer casing 20 and a heat conductive sheet 38 provided on the lower surface of the wide portion 34 of the lid 30, the electrode body 12 can be effectively fixed in close contact with the outer casing 20.

[0038] Furthermore, the protruding portions 26 of the outer casing 20 each have the same overhang length L in the direction toward each other. Therefore, compared to a case where the protruding portions 26 of the outer casing 20 do not have the same overhang length L in the direction toward each other, the assembly of the protruding portions 26 of the outer casing 20 to the lid 30 from the front-rear direction becomes even stronger, and the strength of the assembly portion can be further improved. In other words, the ease of assembly between the outer casing 20 and the lid 30 can be further improved.

[0039] Furthermore, in the lid 30, the thickness H2 of the wide portion 34 is formed to be thicker than the thickness H1 of the narrow portion 32 (H2 > H1). Therefore, even if the thickness of the outer casing 20 (especially the protruding portion 26) is thin, it is possible to prevent damage to the electrode body 12 when welding the lid 30 to the outer casing 20.

[0040] Furthermore, the electrode body 12 has a terminal portion 14 that can close the opening 18 of the outer casing 20. In other words, the attachment of the terminal portion 14 to the electrode body 12 by welding can be performed before the electrode body 12 is inserted into the outer casing 20. Therefore, compared to the case where the terminal portion 14 is welded to the electrode body 12 after the electrode body 12 has been inserted into the outer casing 20, the generation of foreign matter and fumes can be suppressed.

[0041] Furthermore, since the electrode body 12 has a terminal portion 14 that can close the opening 18 of the outer casing 20, the opening 18 can be closed simply by inserting the electrode body 12 into the outer casing 20. In other words, since the cover 30 is also welded and joined to the terminal portion 14, it becomes easier to position and assemble the cover 30 relative to the outer casing 20, thereby improving the ease of assembly between the outer casing 20 and the cover 30.

[0042] The battery 10 according to this embodiment has been described above based on the drawings. However, the battery 10 according to this embodiment is not limited to the illustrated version, and can be modified as appropriate without departing from the spirit of the present invention. For example, the length in the left-right direction, the length in the up-down direction (height), and the length in the front-back direction (thickness) of the battery 10 are not limited to the lengths shown.

[0043] Furthermore, the width (length) of the narrow portion 32 of the lid 30 along the front-rear direction and the overhang length L of the protruding portion 26 of the outer casing 20 are exaggerated in each figure and are not limited to the lengths shown. Therefore, for example, the width (length) of the narrow portion 32 along the front-rear direction may be twice or more the width (length) of the overhang length L of the protruding portion 26. [Explanation of Symbols]

[0044] 10 batteries 12 Electrode body 14 Terminal section 18 Opening 20 Exterior 22 Bottom wall 24 Main wall 26 Overhang 30 Lid 32 Narrow part 34 Wide section

Claims

1. An exterior body having a rectangular, flat bottom wall and a pair of main walls integrally erected on the long sides of the bottom wall, and each of the pair of main walls having an overhang that extends toward each other at the end opposite to the bottom wall, The electrode body housed in the aforementioned outer casing, A lid is provided such that, when viewed in cross-section from a direction along the long side of the bottom wall, it is formed in a "convex" shape having a narrow portion and a wide portion, and the narrow portion is sandwiched in the protruding portion. A battery equipped with this feature.

2. The battery according to claim 1, wherein the outer surface of the narrow portion and the outer surface of the protruding portion are flush.

3. The battery according to claim 1, wherein the overhang length of the overhang portion in the approaching direction is the same.

4. The battery according to claim 1, wherein the thickness of the wide portion is greater than the thickness of the narrow portion.

5. The battery according to claim 1, wherein the electrode body has a terminal portion that can close the opening of the outer casing on the short side of the bottom wall.

6. A method for manufacturing a battery according to any one of claims 1 to 5, An opening step of moving the protruding portions of the exterior body in a direction that separates them from each other to widen the ends, An electrode insertion step involves inserting the electrode into the outer casing whose end has been widened, A cover insertion step involves inserting the cover into the end of the outer casing into which the electrode body is inserted, A sealing step in which the protruding portions are moved toward each other to sandwich the narrow portion of the lid with the protruding portions, thereby sealing the end of the outer casing, A method for manufacturing a battery having [a certain characteristic].

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