Battery

Abstract

Provided is a battery in which a resin member joined to a battery case and a terminal part is not easily damaged. A cover body (5) of a battery case (2) of a battery (1) is provided with a terminal part (30) and a resin member (10). The terminal portion has a terminal plate-shaped portion (32) located inside the battery case and having a shape extending more than the through-hole (53) along an inner surface (52) of the lid body. The resin member has an inner resin plate-shaped portion (13) located between the inner surface of the cover body and the terminal plate-shaped portion. On the periphery of the through hole on the inner surface side of the cover body, a convex part inner surface (52A) to which the inner resin plate-shaped part is joined protrudes toward the inside of the battery case compared with a non-convex part inner surface (52B) farther from the through hole than the convex part inner surface, so that a convex part (55) is provided. A side surface (57) of the protruding portion and a side surface (34) of the terminal plate-shaped portion do not protrude from a side surface (16) of the inner resin plate-shaped portion.

Description

Technical Field

[0001] The disclosed technology relates to a battery having a battery case and a terminal portion. Background Art

[0002] A portion of the terminal portion of the battery is exposed on the surface side of the battery case. The terminal portion is connected to an electrode plate disposed inside the battery case on the opposite side of the side exposed to the outside of the battery case. That is, the terminal portion is disposed in a manner that extends throughout the inside and outside of the battery case. Such a terminal portion, for example, as disclosed in Patent Document 1, is joined to a portion of a through hole formed in the battery case by a resin part. Patent Document 1 describes a situation in which the resin part seals the battery by insulating the battery case from the terminal portion and filling their gaps.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2021-86813

[0004] The resin parts as described above are made of a different material from the battery case and the terminal parts. That is, the linear expansion coefficient of the resin parts is different from the linear expansion coefficient of the battery case and the terminal parts. Therefore, when the temperature of the battery changes, there is a situation where tensile stress is generated near the bonding interface with other parts in the resin parts. Depending on the degree and frequency of the tensile stress, the resin parts may be damaged. Moreover, depending on the degree of damage to the resin parts, for example, problems such as reduced airtightness of the battery may sometimes occur. Summary of the invention

[0005] An object of the disclosed technology is to provide a battery in which a resin member joined to a battery case and a terminal portion is not easily damaged.

[0006] The battery of the disclosed technology comprises: a battery case, which is formed with a through hole; a terminal part, which passes through the through hole and is arranged in a manner extending throughout the inside and outside of the battery case; and a resin part, which is arranged between the battery case and the terminal part and is joined with them, wherein the terminal part comprises: a columnar part, at least a part of which is located inside the through hole; and a terminal plate-like part, which is located inside the battery case and has a shape that is larger than the through hole along the inner surface of the battery case, and the resin part comprises: a tubular part, which is located between the wall surface of the through hole and the columnar part; and a resin plate-like part, which is located between the inner surface of the battery case and the terminal plate-like part, and at the periphery of the through hole located on the inner surface side of the battery case, the joint inner surface to which the resin plate-like part is joined protrudes toward the inside of the battery case compared with the part farther from the through hole than the joint inner surface, thereby providing a convex part, and the side surfaces of the convex part and the side surfaces of the terminal plate-like part do not protrude more than the side surfaces of the resin plate-like part.

[0007] In the above battery, when the battery case, the terminal portion, and the resin member expand or contract due to temperature changes, the stress acting on the resin member is suppressed due to the difference in the extent of expansion or contraction. Therefore, the resin member is less likely to be damaged.

[0008] According to the disclosed technology, a battery is provided in which the resin member joined to the battery case and the terminal portion is not easily damaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a perspective view of a battery according to an embodiment.

[0010] Figure 2 It is a cross-sectional view showing the structure of the external terminal portion in the battery.

[0011] Figure 3 This is a diagram showing an analytical model in which a resin member is joined to a metal.

[0012] Figure 4 This is a diagram showing stress distribution obtained by stress analysis using an analytical model.

[0013] Figure 5 It is a cross-sectional view showing a modified example of the structure of the external terminal.

[0014] Description of reference numerals:

[0015] 1…battery; 2…battery case; 5, 8…cover; 10…resin part; 11…tubular portion; 13…internal resin plate portion; 16…side surface; 30…terminal portion; 31…columnar portion; 32…terminal plate portion; 34…side surface; 52, 82…inner surface; 52A, 82A…convex portion inner surface (joining inner surface); 52B…non-convex portion inner surface; 82B…bottom surface; 53, 83…through hole; 54…wall surface; 55, 85…convex portion; 57, 87…side surface. DETAILED DESCRIPTION

[0016] This method is in Figure 1 The battery 1 shown in the figure is a form in which the disclosed technology is embodied. The battery 1 is formed by accommodating an electrode body 3 in a battery case 2. The electrode body 3 is formed by sandwiching a separator 3C between a positive electrode plate 3A and a negative electrode plate 3B and stacking them. In the battery case 2, in addition to the electrode body 3, an electrolyte is also accommodated.

[0017] The battery case 2 includes a box body 4 and a cover body 5. The cover body 5 is provided with positive and negative external terminals 6 and 7. When the battery 1 is viewed from the outside, the terminal surfaces 6A and 7A and the resin parts 10 and 20 are visible at the locations of the external terminals 6 and 7. The external terminal 6 is a positive terminal. The external terminal 7 is a negative terminal.

[0018] use Figure 2 The structure of the external terminal 6 will be described. Figure 2 yes Figure 1 The cross-sectional view at the position A-A is shown in the figure. Figure 2 As shown, a terminal portion 30 is provided at the location of the external terminal 6. The terminal portion 30 is provided from the outer surface 51 of the cover 5 closer to the Figure 2 The upper surface side of the cover 5 is closer to the inner surface 52 of the cover 5. Figure 2 A component provided on the inner side of the lower side of the Figure 2 In the figure, the lower side than the inner surface 52 of the cover 5 is the inside of the battery case 2. Therefore, the terminal portion 30 is provided so as to extend over the inside and outside of the battery case 2. In addition, the resin member 10 is provided between the cover 5 and the terminal portion 30.

[0019] The cover 5 is made of a conductive metal material. In this embodiment, the cover 5 is made of aluminum. A through hole 53 is formed in the cover 5 at the location of the external terminal 6, through which the terminal portion 30 passes. Figure 2 5 shows the wall surface 54 of the through hole 53. The cover 5 has a convex portion 55 at a location located on the inner side of the battery case 2 (ie, the inner surface 52 side) and at the periphery of the through hole 53.

[0020] The convex portion 55 is a portion that protrudes toward the inside of the battery case 2 compared to a portion that is farther from the through hole 53 than the convex portion 55. Figure 2 In the embodiment, the portion farther from the through hole 53 than the convex portion 55 is represented as a non-convex portion 56. In addition, in the inner surface 52, the portion where the convex portion 55 is located is represented as a convex portion inner surface 52A, and the portion where the non-convex portion 56 is located is represented as a non-convex portion inner surface 52B. In this embodiment, the convex portion inner surface 52A is the end surface of the convex portion 55 in the protruding direction thereof.

[0021] The convex inner surface 52A protrudes further into the battery case 2 than the non-convex inner surface 52B. That is, a step is formed on the inner surface 52 of the lid 5 by the convex portion 55 and the non-convex portion 56. Figure 2 , the side surface 57 of the convex portion 55 located at the position of the step difference is shown. The side surface 57 is a surface connecting the convex portion inner surface 52A and the non-convex portion inner surface 52B. The opening of the through hole 53 on the inner side of the battery case 2 is located on the convex portion inner surface 52A. That is, the through hole 53 is provided in the area surrounded by the side surface 57 of the convex portion 55 in the cover body 5.

[0022] The terminal portion 30 is made of a conductive metal material. In this embodiment, the terminal portion 30 is made of aluminum. The terminal portion 30 includes a columnar portion 31, a terminal plate portion 32, and a collector portion 33. The columnar portion 31 passes through the through hole 53, and one end side is exposed to the outside of the battery case 2. The exposed surface of the columnar portion 31 is the terminal surface 6A. At least a portion of the columnar portion 31 is located inside the through hole 53.

[0023] The terminal plate-shaped portion 32 is provided at a position closer to the inside of the battery case 2 than the columnar portion 31. The terminal plate-shaped portion 32 is connected to the columnar portion 31. The terminal plate-shaped portion 32 is shaped to expand more than the columnar portion 31 along the inner surface 52A of the convex portion inside the battery case 2. In addition, the terminal plate-shaped portion 32 of this embodiment is shaped to expand more than the through hole 53. Figure 2 , the side surface 34, the first main surface 35, and the second main surface 36 of the terminal plate-shaped portion 32 are shown. The first main surface 35 of the terminal plate-shaped portion 32 is the surface of the terminal plate-shaped portion 32 that is opposite to the inner surface 52 of the cover body 5. The second main surface 36 of the terminal plate-shaped portion 32 is the back side of the first main surface 35.

[0024] The current collecting portion 33 is provided at a position closer to the inner side of the battery case 2 than the terminal plate-shaped portion 32. The current collecting portion 33 is connected to the terminal plate-shaped portion 32 at one end. The current collecting portion 33 is connected to the positive electrode plate 3A constituting the electrode body 3 on the side opposite to the side connected to the terminal plate-shaped portion 32. The current collecting portion 33 of this embodiment is formed thinner than the terminal plate-shaped portion 32.

[0025] The resin part 10 is a material made of insulating resin. In the present embodiment, it is a composite resin in which a filler is mixed in a base resin. Examples of resins that can be used as base resins include polyphenylene sulfide resin (PPS) and polyarylene sulfide (PAS). Examples of materials that can be used as fillers include glass, alumina, potassium titanate, and the like. In the present embodiment, PPS resin is used as the base resin, and glass is used as the filler. The resin part 10 of the present embodiment has a higher mechanical strength than a material that is not mixed with a filler because a filler is mixed in the base resin.

[0026] The resin part 10 includes a tubular portion 11, an external resin plate-shaped portion 12, and an internal resin plate-shaped portion 13. The tubular portion 11 is located between the wall surface 54 of the through hole 53 and the columnar portion 31. The external resin plate-shaped portion 12 is provided at a position closer to the outside of the battery case 2 than the tubular portion 11. The external resin plate-shaped portion 12 is connected to the tubular portion 11. The external resin plate-shaped portion 12 is exposed to the outside on the outer surface 51 of the cover body 5. Specifically, the upper surface 14 and the side surface 15 of the external resin plate-shaped portion 12 are exposed to the outside of the battery case 2.

[0027] The inner resin plate-shaped portion 13 is provided at a position closer to the inner side of the battery case 2 than the tubular portion 11. The inner resin plate-shaped portion 13 is connected to the tubular portion 11. The inner resin plate-shaped portion 13 is expanded inside the battery case 2 to a greater extent than the through hole 53. Figure 2, the side surface 16, the first main surface 17, and the second main surface 18 of the internal resin plate-like portion 13 are shown. The first main surface 17 of the internal resin plate-like portion 13 is a surface facing the inner surface 52 of the cover body 5. The second main surface 18 of the internal resin plate-like portion 13 is the back side of the first main surface 17. In addition, the second main surface 18 of the internal resin plate-like portion 13 is a surface facing the first main surface 35 of the terminal plate-like portion 32. Moreover, the internal resin plate-like portion 13 is located between the inner surface 52A of the convex portion in the inner surface 52 of the cover body 5 and the terminal plate-like portion 32.

[0028] The resin part 10 is formed in the following manner: the cover body 5 and the terminal part 30 are held in a predetermined positional relationship, and a molten resin is filled between them, and then the filled resin is solidified. That is, the cover body 5, the resin part 10, and the terminal part 30 are integrally formed by insert molding. Thus, the resin part 10 is joined to the cover body 5 and the terminal part 30.

[0029] That is, the internal resin plate-shaped portion 13 is joined to the convex portion 55 of the cover body 5 and the terminal plate-shaped portion 32 of the terminal portion 30. Specifically, the first main surface 17 of the internal resin plate-shaped portion 13 is joined to the convex inner surface 52A of the convex portion 55 of the cover body 5. Therefore, the convex inner surface 52A is the joined inner surface of the internal resin plate-shaped portion 13 to which the resin member 10 is joined among the inner surfaces 52. The second main surface 18 of the internal resin plate-shaped portion 13 is joined to the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30. That is, the internal resin plate-shaped portion 13 is joined to these metals in a state of being sandwiched by metals having a different linear expansion coefficient from that of the internal resin plate-shaped portion 13. Moreover, in this embodiment, the side surface 57 of the convex portion 55 of the cover body 5 and the side surface 34 of the terminal plate-shaped portion 32 of the terminal portion 30 do not protrude beyond the side surface 16 of the internal resin plate-shaped portion 13. Regarding the shapes of the cover 5, the resin member 10, and the terminal portion 30 at the location of the external terminal 6, as long as the cross section is along the central axis of the through hole 53, even if it is in the same Figure 2 Different section positions are also roughly the same Figure 2 Same shape.

[0030] exist Figure 3, an analytical model M of a structure in which a resin is sandwiched between two metal sheets is shown. The analytical model M is composed of three layers, namely, an intermediate layer model M1, a first surface layer model M2, and a second surface layer model M3. The first surface layer model M2 is bonded to the first main surface M1A of the intermediate layer model M1. The second surface layer model M3 is bonded to the second main surface M1B of the intermediate layer model M1. The second main surface M1B is the back side of the intermediate layer model M1 located on the opposite side of the first main surface M1A. The parameters of the intermediate layer model M1 are based on a material in which glass is mixed with a PPS resin as a base resin as a filler. That is, the parameters of the intermediate layer model M1 are values ​​based on the resin part 10. In addition, the parameters of the first surface layer model M2 and the second surface layer model M3 are parameters based on aluminum. That is, the parameters of the first surface layer model M2 and the second surface layer model M3 are values ​​based on the cover body 5 and the terminal portion 30. That is, the analytical model M simulates the inner resin plate-like portion 13 of the resin member 10 with the protrusion 55 of the cover 5 and the terminal plate-like portion 32 of the terminal portion 30 bonded to the front and back surfaces, respectively.

[0031] exist Figure 3 , the side surface M1S of the intermediate layer model M1, the side surface M2S of the first surface model M2, and the side surface M3S of the second surface model M3 are shown. The side surface M2S of the first surface model M2 and the side surface M1S of the intermediate layer model M1 are aligned on the same plane. On the other hand, the side surface M3S of the second surface model M3 protrudes more than the side surface M1S of the intermediate layer model M1. The second surface model M3 has a protrusion M3T that protrudes more than the side surface M1S of the intermediate layer model M1. That is, the second surface model M3 is different from the structure of the external terminal 6 described above, and is a metal material having a portion that protrudes more than the resin part.

[0032] Figure 4 It means by using Figure 3 The stress distribution diagram of the analytical model M shown in FIG. Figure 4 , the stress distribution of the intermediate layer model M1 when the temperature is changed for the analytical model M is shown. Due to the temperature change, expansion and contraction occur in each component. The degree of expansion and contraction differs depending on the metal material and the resin part. Therefore, according to the difference in the degree of expansion and contraction between the metal material and the resin part, stress acts on the intermediate layer model M1 as the resin part.

[0033] The stress distribution is shown by the density of dots or oblique lines. The higher the density of dots or oblique lines, the higher the stress. For areas with relatively low stress, dots are used to represent them. For areas with higher stress than the range represented by dots, oblique lines are used to represent them. That is, for the area H represented by oblique lines, it is confirmed that it is a high stress area.

[0034] from Figure 4It can be seen that the region H is biased toward the second main surface M1B side compared to the first main surface M1A side in the side surface M1S of the intermediate layer model M1. The second main surface M1B is a surface of the second surface layer model M3 joined with a protrusion M3T protruding from the side surface M1S of the intermediate layer model M1. Based on this, it can be confirmed that in a resin part joined with a metal material on the front and back surfaces, when a metal material having a portion protruding from its side surface is joined, high stress tends to concentrate near the joint surface joined with the protruding metal material. Moreover, it can be confirmed that when the side surface of the metal material does not protrude from the side surface of the resin part, the stress acting on the resin part is relieved compared with the case of protrusion.

[0035] As described above, in this embodiment, the side surface 57 of the convex portion 55 of the cover 5 and the side surface 34 of the terminal plate-shaped portion 32 of the terminal portion 30 do not protrude beyond the side surface 16 of the internal resin plate-shaped portion 13. Therefore, in the battery 1 of this embodiment, when a temperature change occurs, the high stress acting on the internal resin plate-shaped portion 13 is suppressed. Therefore, damage to the resin member 10 is suppressed.

[0036] In addition, it is actually difficult to align both the side surface 57 of the convex portion 55 of the cover body 5 and the side surface 34 of the terminal plate-shaped portion 32 of the terminal portion 30 with the side surface 16 of the internal resin plate-shaped portion 13 on the same plane. Therefore, it is preferable to form the side surface 16 of the internal resin plate-shaped portion 13 to protrude more than at least one of the side surface 57 of the convex portion 55 of the cover body 5 and the side surface 34 of the terminal plate-shaped portion 32 of the terminal portion 30. Thus, it is possible to more reliably suppress the high stress from acting on the side of the internal resin plate-shaped portion 13 to which the metal material of one of the two is bonded. That is, it is possible to more reliably suppress the damage to the resin part 10. In addition, it is also possible to make the side surface 16 of the internal resin plate-shaped portion 13 protrude more than any one of the side surface 57 of the convex portion 55 of the cover body 5 and the side surface 34 of the terminal plate-shaped portion 32 of the terminal portion 30. Thus, it is possible to further reliably suppress the high stress from acting on the entire internal resin plate-shaped portion 13. That is, it is possible to further reliably suppress the damage to the resin part 10.

[0037] In addition, the resin part 10 is formed by mixing fillers in the base resin. Moreover, it is preferred that the main orientation direction of the fillers in the internal resin plate-shaped portion 13 is parallel to the joint surface of the internal resin plate-shaped portion 13 that is joined to the metal material. In this embodiment, the main orientation direction of the fillers in the internal resin plate-shaped portion 13 is parallel to the convex inner surface 52A of the convex portion 55 of the cover body 5 and the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30.

[0038] Generally, in a resin part containing fillers, there is a tendency to improve the mechanical strength in the orientation direction of the fillers compared to the direction intersecting the orientation direction. Moreover, in the resin part, when a temperature change occurs, a force that is stretched by the metal material acts near the joint surface with the metal material having a different linear expansion coefficient. The direction of this force is roughly parallel to the direction of the joint surface of the resin part that is joined with the metal material. Therefore, by making the main orientation direction of the fillers in the internal resin plate-shaped portion 13 parallel to the joint surface of the internal resin plate-shaped portion 13 that is joined with the metal material, damage to the resin part 10 can be suppressed.

[0039] Specifically, it is preferred that the average orientation direction of the filler matched with the internal resin plate-shaped portion 13 has an angle of 20° or less relative to the surface of the metal material joined to the internal resin plate-shaped portion 13. This is because the stress acting on the internal resin plate-shaped portion 13 when a temperature change occurs can be relaxed to a degree that can appropriately suppress damage to the internal resin plate-shaped portion 13. In this embodiment, the convex inner surface 52A of the convex portion 55 of the cover body 5 is parallel to the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30. That is, the angle of the average orientation direction of the filler in the internal resin plate-shaped portion 13 relative to the convex inner surface 52A of the convex portion 55 of the cover body 5 is the same as the angle of the average orientation direction of the filler in the internal resin plate-shaped portion 13 relative to the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30.

[0040] Furthermore, even when the convex inner surface 52A of the convex portion 55 of the cover body 5 is not parallel to the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30, it is preferred that the average orientation direction of the filler in the internal resin plate-shaped portion 13 is 20° or less relative to either of them. The angle of the average orientation direction of the filler matched with the internal resin plate-shaped portion 13 relative to the surface of the metal material joined to the internal resin plate-shaped portion 13 tends to be as small as possible. Therefore, it is more preferred that the average orientation direction of the filler matched with the internal resin plate-shaped portion 13 is 15° or less relative to the surface of the metal material joined to the internal resin plate-shaped portion 13.

[0041] In this embodiment, the angle between the average orientation direction of the fillers in the internal resin plate-shaped portion 13 and the surface of the metal material to which the internal resin plate-shaped portion 13 is joined can be obtained using a CT image. That is, in a CT image obtained for a cross section intersecting the surface of the metal material to which the internal resin plate-shaped portion 13 is joined, the angle of the long side direction of the fillers relative to the surface reference line of the metal material can be calculated for a plurality of fillers and obtained by arithmetic average thereof. The surface reference line of the metal material in the CT image can be an average line for any five points extracted from the surface of the metal material.

[0042] In addition, it is preferred that a micro-concave-convex shape is formed on the surface of the metal material joined to the resin part 10, and a micro-anchor structure is formed by causing the resin part 10 to sink into the concave-convex shape. The micro-concave-convex shape can be formed by irradiating the surface of the metal material with a laser to thereby perform a rough surface processing. In the area where such an anchor structure is formed, the bonding strength between the resin part 10 and the metal material can be improved. That is, it is possible to suppress the resin part 10 from peeling off from the metal material.

[0043] It is preferable that such a concavo-convex shape is formed in at least a part of the convex inner surface 52A of the convex portion 55 of the cover body 5 facing the internal resin plate-shaped portion 13. This is because it is possible to suppress the internal resin plate-shaped portion 13 from peeling off from the convex portion 55 of the cover body 5. In addition, it is preferable that the concavo-convex shape is formed in at least a part of the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30 facing the internal resin plate-shaped portion 13. This is because it is possible to suppress the internal resin plate-shaped portion 13 from peeling off from the terminal plate-shaped portion 32. In addition, it is preferable that the concavo-convex shape is formed in both the convex inner surface 52A of the convex portion 55 of the cover body 5 and the first main surface 35 of the terminal plate-shaped portion 32. This is because it is possible to suppress the internal resin plate-shaped portion 13 from peeling off from the convex portion 55 and the internal resin plate-shaped portion 13 from peeling off from the first main surface 35 of the terminal plate-shaped portion 32.

[0044] In this embodiment, even when the bonding strength between the internal resin plate-shaped portion 13 and the metal material is high, when a temperature change occurs, it is possible to suppress the high stress from acting on the internal resin plate-shaped portion 13. Therefore, it is possible to suppress damage to the internal resin plate-shaped portion 13. That is, when a temperature change occurs, the peeling of the internal resin plate-shaped portion 13 and the damage to the internal resin plate-shaped portion 13 are suppressed.

[0045] As described in detail above, the battery 1 of this embodiment includes a battery case 2, a terminal portion 30, and a resin member 10. The battery case 2 includes a cover 5. A through hole 53 is formed in the cover 5. The terminal portion 30 is provided to extend through the through hole 53 to the inside and outside of the battery case 2. The resin member 10 is provided between the cover 5 of the battery case 2 and the terminal portion 30. The resin member 10 is joined to the cover 5 and the terminal portion 30. In addition, the terminal portion 30 includes a columnar portion 31 and a terminal plate-shaped portion 32. At least a portion of the columnar portion 31 is located inside the through hole 53. The terminal plate-shaped portion 32 is located inside the battery case 2 and has a shape that is larger than the through hole 53 along the inner surface 52 of the cover 5. The resin member 10 includes a tubular portion 11 and an internal resin plate-shaped portion 13. The tubular portion 11 is located between the wall surface 54 of the through hole 53 and the columnar portion 31. The internal resin plate-shaped portion 13 is located between the inner surface 52 of the cover 5 and the terminal plate-shaped portion 32. At the periphery of the through hole 53 located on the inner surface 52 side of the cover 5, the convex inner surface 52A to which the internal resin plate-shaped portion 13 is joined and the non-convex inner surface 52B which is farther from the through hole 53 than the convex inner surface 52A protrudes toward the inside of the battery case 2, thereby providing a convex portion 55. Moreover, the side surface 57 of the convex portion 55 and the side surface 34 of the terminal plate-shaped portion 32 do not protrude from the side surface 16 of the internal resin plate-shaped portion 13. Thus, the stress acting on the internal resin plate-shaped portion 13 when the temperature changes can be suppressed. Therefore, a battery 1 in which the resin member 10 is not easily damaged is realized.

[0046] The present embodiment and examples are merely illustrative and do not limit the disclosed technology in any way. Therefore, the disclosed technology can of course be modified and altered in various ways without departing from the gist of the invention.

[0047] For example, the area where the micro-anchor structure is formed can be appropriately adjusted. That is, for example, a micro-concave-convex shape can be formed in the entire area of ​​the surface of the cover 5 and the terminal portion 30 where the resin part 10 is bonded. In addition, for example, a micro-concave-convex shape can also be formed on the entire surface of at least one of the convex inner surface 52A of the convex portion 55 and the first main surface 35 of the terminal plate-shaped portion 32. In addition, for example, in the case where a micro-concave-convex shape is formed in at least a part of the convex inner surface 52A of the convex portion 55 and the first main surface 35 of the terminal plate-shaped portion 32, it is preferred that the area where the concave-convex shape is formed is a continuous area in a manner surrounding the through hole 53. This is because the airtightness of the battery case 2 can be maintained at a higher level.

[0048] In addition, for example, as long as the side surface 57 of the protrusion 55 is provided so as to surround the opening of the through hole 53 on the inner surface 52 side of the cover body 5, the portion of the cover body that is farther from the through hole 53 than the protrusion 55 can be of any shape. Figure 5The cover 8 shown in the figure. A through hole 83 is formed in the cover 8, which passes from the outer surface 81 to the inner surface 82. A continuous groove 86 is formed in an annular shape on the inner surface 82 of the cover 8 so as to surround the opening of the through hole 83. Thus, a convex portion 85 is provided on the inner side of the groove 86, that is, on the through hole 83 side of the groove 86. The inner resin plate-shaped portion 13 of the resin member 10 is joined to the convex inner surface 82A of the convex portion 85. In addition, even in the case of the cover 8 of this shape, the convex inner surface 82A protrudes toward the inside of the battery case 2 compared with the bottom surface 82B of the groove 86 which is farther from the through hole 83 than the convex inner surface 82A. Moreover, even in the case of using the cover 8, it is sufficient as long as the side surface 87 of the convex portion 85 does not protrude beyond the side surface 16 of the inner resin plate-shaped portion 13.

[0049] In addition, for example, the external terminal 6 may also be provided in the box body 4 of the battery case 2. In addition, for example, the terminal portion 30 may be composed of one component or may be composed by connecting a plurality of components. In addition, for example, for each component related to the external terminal 6 described above, the cross-sectional shape perpendicular to the axial direction of the through hole 83 is a quadrilateral. However, it is not limited to a quadrilateral, and for example, a circular shape may also be adopted.

[0050] In addition, for example, in the above, the structure of the external terminal 6 side as the positive electrode is specifically described. However, the same structure can be used for the external terminal 7 side as the negative electrode. For the external terminal 7 side as the negative electrode, a material different from that on the positive electrode side can be appropriately used. For example, in the structure on the external terminal 7 side, a copper terminal portion can be used as the terminal portion connected to the negative electrode plate 3B on the inner side of the battery case 2. In addition, the disclosed technology can also be applied only to either the structure on the external terminal 6 side as the positive electrode or the structure on the external terminal 7 side as the negative electrode.

[0051] In addition, the above disclosed technology includes the following structures 1 to 4.

[0052] [Structure 1]

[0053] A battery having:

[0054] A battery housing having a through hole formed therein;

[0055] a terminal portion that passes through the through hole and is provided so as to extend over the inside and outside of the battery case; and

[0056] a resin member disposed between the battery case and the terminal portion and joined to the battery case and the terminal portion,

[0057] in,

[0058] The terminal portion has:

[0059] a columnar portion, at least a portion of which is located inside the through hole; and

[0060] a terminal plate-shaped portion, the terminal plate-shaped portion being located inside the battery case and extending along the inner surface of the battery case in a shape larger than the through hole,

[0061] The resin part has:

[0062] a tubular portion located between a wall surface of the through hole and the columnar portion; and

[0063] a resin plate-like portion, the resin plate-like portion being located between the inner surface of the battery case and the terminal plate-like portion,

[0064] A convex portion is provided at the periphery of the through hole located on the inner surface side of the battery case, where the inner surface joined to the resin plate-like portion protrudes toward the inside of the battery case compared to a portion farther from the through hole than the inner surface joined to the resin plate-like portion.

[0065] Neither the side surface of the protrusion nor the side surface of the terminal plate-shaped portion protrudes beyond the side surface of the resin plate-shaped portion.

[0066] [Structure 2]

[0067] In the battery according to the above structure 1,

[0068] The side surface of the resin plate-shaped portion protrudes more than at least one of the side surface of the convex portion and the side surface of the terminal plate-shaped portion.

[0069] [Structure 3]

[0070] In the battery according to the above structure 1 or 2,

[0071] The above resin parts are made by mixing fillers in the base resin.

[0072] A main orientation direction of the filler in the resin plate-shaped portion is parallel to the joint inner surface and a joint surface of the terminal plate-shaped portion that is joined to the resin plate-shaped portion.

[0073] [Structure 4]

[0074] In the battery described in any one of the above structures 1 to 3,

[0075] A microscopic concavo-convex shape is formed in a region of at least one of the convex portion and the terminal plate-shaped portion that faces the resin plate-shaped portion, and an anchor structure is formed by causing the resin member to sink into the concavo-convex shape.

Claims

1. A battery having: A battery housing having a through hole formed therein; a terminal portion that passes through the through hole and is provided so as to extend over the inside and outside of the battery case; and a resin member disposed between the battery case and the terminal portion and joined to the battery case and the terminal portion, The battery is characterized in that The terminal portion has: a columnar portion, at least a portion of which is located inside the through hole; and a terminal plate-shaped portion, the terminal plate-shaped portion being located inside the battery case and extending along the inner surface of the battery case in a shape larger than the through hole, The resin part has: a tubular portion located between a wall surface of the through hole and the columnar portion; and a resin plate-shaped portion located between the inner surface of the battery case and the terminal plate-shaped portion, A convex portion is provided at the periphery of the through hole located on the inner surface side of the battery case, wherein the joining inner surface to which the resin plate-shaped portion is joined protrudes toward the inside of the battery case compared to a portion farther from the through hole than the joining inner surface. Neither the side surface of the convex portion nor the side surface of the terminal plate-shaped portion protrudes beyond the side surface of the resin plate-shaped portion.

2. The battery according to claim 1, characterized in that The side surface of the resin plate-shaped portion protrudes more than at least one of the side surface of the convex portion and the side surface of the terminal plate-shaped portion.

3. The battery according to claim 1, characterized in that The resin part is formed by mixing fillers in a base resin. A main orientation direction of the filler in the resin plate-shaped portion is parallel to the joint inner surface and a joint surface of the terminal plate-shaped portion that is joined to the resin plate-shaped portion.

4. The battery according to claim 2, characterized in that The resin part is formed by mixing fillers in a base resin. A main orientation direction of the filler in the resin plate-shaped portion is parallel to the joint inner surface and a joint surface of the terminal plate-shaped portion that is joined to the resin plate-shaped portion.

5. The battery according to any one of claims 1 to 4, characterized in that A fine concavo-convex shape is formed in a region of at least one of the convex portion and the terminal plate-shaped portion that faces the resin plate-shaped portion, The anchor structure is formed by causing the resin member to sink into the concavo-convex shape.

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