Battery

Abstract

To provide a battery in which a resin material bonded to a battery case and a terminal part is hardly damaged.SOLUTION: A terminal part 30 and a resin material 10 are provided on a lid 5 of a battery case 2 of a battery 1. The terminal part 30 is located inside the battery case 2, and has a terminal tabular part 32 with a shape expanding to larger than a through-hole 53, along an inner surface 52 of the lid 5. The resin material 10 has an inner resin tabular part 13 which is located between the inner surface 52 of the lid 5 and the terminal tabular part 32. A protrusion inner surface 52A, to which the inner resin tabular part 13 is bonded, further protrudes toward the inside of the battery case 2 compared with a non-protrusion inner surface 52B, which is located farther from the through-hole 53 than the protrusion inner surface 52A, thus providing a protrusion 55 on a circumference of the through-hole 53 on the inner surface 52 side of the lid 5. Neither a lateral surface 57 of the protrusion 55 nor a lateral surface 34 of the terminal tabular part 32 protrudes further than a lateral surface 16 of the inner resin tabular part 13.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] A part of the terminal of the battery is exposed on the front side of the battery case. The terminal is connected to an electrode plate provided inside the battery case on the side opposite to the side exposed to the outside of the battery case. In other words, the terminal is provided on both the inside and outside of the battery case. Such a terminal may be bonded to a through hole formed in the battery case by a resin material, as disclosed in Patent Document 1, for example. Patent Document 1 describes that the resin material insulates the battery case and the terminal while filling the gap between them to seal the battery. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-86813 Summary of the Invention [Problem to be solved by the invention]

[0004] The resin material as described above is a material different from that of the battery case and the terminal parts. In other words, the linear expansion coefficient of the resin material is different from that of the battery case and the terminal parts. For this reason, when the temperature of the battery changes, tensile stress may occur near the bonding interface between the resin material and other members. Depending on the degree and frequency of the action of the tensile stress, the resin material may be damaged. Depending on the degree of damage to the resin material, problems such as a decrease in the sealing property of the battery may occur.

[0005] An object of the present disclosure is to provide a battery in which the resin material joined between the battery case and the terminal portion is less likely to be damaged. [Means for solving the problem]

[0006] The battery according to the disclosed technology has a battery case in which a through hole is formed, a terminal portion that passes through the through hole and is provided on both the inside and outside of the battery case, and a resin material that is provided between the battery case and the terminal portion and joined thereto, wherein the terminal portion has a columnar portion at least a portion of which is located inside the through hole, and a terminal plate portion that is located inside the battery case and has a shape that is wider than the through hole along the inner surface of the battery case, and the resin material has a tubular portion that is located between the wall surface of the through hole and the columnar portion, and a resin plate portion that is located between the inner surface of the battery case and the terminal plate portion, and a convex portion is provided on the periphery of the through hole on the inner surface side of the battery case, whereby the joining inner surface to which the resin plate portion is joined protrudes toward the inside of the battery case compared to a point farther from the through hole than the joining inner surface, and the battery case has a side surface of the convex portion and a side surface of the terminal plate portion that do not protrude further than the side surface of the resin plate portion.

[0007] In the battery according to the above, when expansion and contraction occurs in the battery case, terminals, and resin material due to temperature change, the stress acting on the resin material is suppressed depending on the difference in the degree of expansion and contraction, and therefore the resin material is less likely to be damaged. Effect of the Invention

[0008] According to the disclosed technique, a battery is provided in which the resin material that is joined between the battery case and the terminal portion is less likely to be damaged. [Brief description of the drawings]

[0009] [Figure 1] 1 is a perspective view of a battery according to an embodiment; [Diagram 2] FIG. 2 is a cross-sectional view showing the structure of an external terminal portion of a battery. [Diagram 3] FIG. 13 is a diagram showing an analytical model in which a resin material is bonded to a metal. [Figure 4] FIG. 13 is a diagram showing a stress distribution obtained by a stress analysis using an analytical model. [Diagram 5]13 is a cross-sectional view showing a modified example of the structure of the external terminal portion. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] This embodiment embodies the disclosed technology in a battery 1 shown in Fig. 1. The battery 1 is configured by housing an electrode assembly 3 in a battery case 2. The electrode assembly 3 is configured by stacking a positive electrode plate 3A and a negative electrode plate 3B with a separator 3C sandwiched between them. In addition to the electrode assembly 3, an electrolyte is also housed inside the battery case 2.

[0011] The battery case 2 also has a box body 4 and a lid body 5. The lid body 5 is provided with positive and negative external terminals 6, 7. When viewed from the outside of the battery 1, terminal surfaces 6A, 7A and resin materials 10, 20 are visible at the locations of the external terminals 6, 7. The external terminal 6 is a positive terminal. The external terminal 7 is a negative terminal.

[0012] The structure of the location of the external terminal 6 will be described with reference to FIG. 2. FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1. As shown in FIG. 2, a terminal portion 30 is provided at the location of the external terminal 6. The terminal portion 30 is a member provided across the front side, which is above the outer surface 51 of the lid body 5 in FIG. 2, and the back side, which is below the inner surface 52 of the lid body 5 in FIG. 2. In FIG. 2, the side below the inner surface 52 of the lid body 5 is the inside of the battery case 2. Therefore, the terminal portion 30 is provided across the inside and outside of the battery case 2. In addition, a resin material 10 is provided between the lid body 5 and the terminal portion 30.

[0013] The lid body 5 is made of a conductive metal material. In this embodiment, the lid body 5 is made of aluminum. At the location of the external terminal 6, the lid body 5 is formed with a through hole 53 through which the terminal portion 30 passes. FIG. 2 shows a wall surface 54 of the through hole 53. The lid body 5 has a protrusion 55 at a location located on the periphery of the through hole 53 on the inside of the battery case 2 (i.e., on the side of the inner surface 52).

[0014] The convex portion 55 is a portion that protrudes toward the inside of the battery case 2 more than a portion that is farther away from the through hole 53 than the convex portion 55. The portion that is farther away from the through hole 53 than the convex portion 55 is shown in Fig. 2 as a non-convex portion 56. Further, of the inner surface 52, a portion at the convex portion 55 is shown as a convex portion inner surface 52A, and a portion at the non-convex portion 56 is shown as a non-convex portion inner surface 52B. In this embodiment, the convex portion inner surface 52A is an end face of the convex portion 55 in the protruding direction.

[0015] The convex inner surface 52A protrudes further toward the inside of 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. FIG. 2 shows a side surface 57 of the convex portion 55 at the position of the step. The side surface 57 is a surface that connects the convex inner surface 52A and the non-convex inner surface 52B. The opening of the through hole 53 on the inside of the battery case 2 is located on the convex inner surface 52A. That is, the through hole 53 is provided in a region of the lid 5 that is surrounded by the side surface 57 of the convex portion 55.

[0016] 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 has a columnar portion 31, a terminal plate portion 32, and a current collecting portion 33. The columnar portion 31 passes through the inside of 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.

[0017] The terminal plate-shaped portion 32 is provided on the inner side of the battery case 2 relative to the columnar portion 31. The terminal plate-shaped portion 32 is connected to the columnar portion 31. The terminal plate-shaped portion 32 has a shape that is wider than the columnar portion 31 along the inner surface 52A of the protrusion inside the battery case 2. The terminal plate-shaped portion 32 in this embodiment has a shape that is wider than the through hole 53. FIG. 2 shows the side surface 34, the first main surface 35, and the second main surface 36 of the terminal plate-shaped portion 32. The first main surface 35 of the terminal plate-shaped portion 32 is a surface of the terminal plate-shaped portion 32 that faces the inner surface 52 of the cover body 5. The second main surface 36 of the terminal plate-shaped portion 32 is a back surface of the first main surface 35.

[0018] The current collecting portion 33 is provided on the inner side of the battery case 2 relative to the terminal plate-shaped portion 32. The terminal plate-shaped portion 32 is connected to the terminal plate-shaped portion 32. 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 in this embodiment is formed thinner than the terminal plate-shaped portion 32.

[0019] The resin material 10 is made of a resin having insulating properties. In this embodiment, it is a composite resin in which a filler is mixed with a base resin. Examples of resins that can be used as the base resin include polyphenylene sulfide resin (PPS) and polyarylene sulfide (PAS). Examples of materials that can be used as the filler include glass, alumina, and potassium titanate. In this embodiment, PPS resin is used as the base resin, and glass is used as the filler. Since the resin material 10 in this embodiment includes a filler mixed with the base resin, it has a higher mechanical strength than one that does not include a filler.

[0020] The resin material 10 has a tubular portion 11, an external resin plate portion 12, and an internal resin plate portion 13. The tubular portion 11 is located between a wall surface 54 of the through hole 53 and the columnar portion 31. The external resin plate portion 12 is provided on the external side of the battery case 2 relative to the tubular portion 11. The external resin plate portion 12 is connected to the tubular portion 11. The external resin plate portion 12 is exposed to the outside on the outer surface 51 of the lid body 5. Specifically, an upper surface 14 and a side surface 15 of the external resin plate portion 12 are exposed to the outside of the battery case 2.

[0021] The internal resin plate-shaped portion 13 is provided on the inner side of the battery case 2 relative to the tubular portion 11. The internal resin plate-shaped portion 13 is connected to the tubular portion 11. The internal resin plate-shaped portion 13 is wider than the through hole 53 inside the battery case 2. FIG. 2 shows the side surface 16, the first main surface 17, and the second main surface 18 of the internal resin plate-shaped portion 13. The first main surface 17 of the internal resin plate-shaped portion 13 is a surface facing the inner surface 52 of the lid body 5. The second main surface 18 of the internal resin plate-shaped portion 13 is a back surface of the first main surface 17. The second main surface 18 of the internal resin plate-shaped portion 13 is a surface facing the first main surface 35 of the terminal plate-shaped portion 32. The internal resin plate-shaped portion 13 is located between the convex inner surface 52A of the inner surface 52 of the lid body 5 and the terminal plate-shaped portion 32.

[0022] The resin material 10 is formed by filling the gap between the lid body 5 and the terminal portion 30 with molten resin while holding them in a predetermined positional relationship, and then solidifying the filled resin. That is, the lid body 5, the resin material 10, and the terminal portion 30 are integrally formed by insert molding. In this way, the resin material 10 is bonded to the lid body 5 and the terminal portion 30.

[0023] That is, the internal resin plate-like portion 13 is joined to the convex portion 55 of the lid body 5 and the terminal plate-like portion 32 of the terminal portion 30. Specifically, the first main surface 17 of the internal resin plate-like portion 13 is joined to the convex portion inner surface 52A of the convex portion 55 of the lid body 5. Therefore, the convex portion inner surface 52A is the joining inner surface of the inner surface 52 to which the internal resin plate-like portion 13 of the resin material 10 is joined. The second main surface 18 of the internal resin plate-like portion 13 is joined to the first main surface 35 of the terminal plate-like portion 32 of the terminal portion 30. That is, the internal resin plate-like portion 13 is sandwiched between metals having linear expansion coefficients different from those of the internal resin plate-like portion 13 and joined to those metals. In this embodiment, the side surface 57 of the convex portion 55 of the lid body 5 and the side surface 34 of the terminal plate-like portion 32 of the terminal portion 30 are both configured not to protrude beyond the side surface 16 of the internal resin plate-like portion 13. The shapes of the lid 5, resin material 10, and terminal portion 30 at the location of the external terminal 6 are generally the same as those in FIG. 2 even at cross-sectional positions other than those in FIG. 2, as long as the cross-section is taken along the central axis of the through-hole 53.

[0024] FIG. 3 shows an analytical model M having a structure in which resin is sandwiched between two metals. The analytical model M is composed of three layers, 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 surface of the first main surface M1A. The parameters of the intermediate layer model M1 are based on a PPS resin as a base resin mixed with glass as a filler. That is, the parameters of the intermediate layer model M1 are based on values ​​based on the resin material 10. The parameters of the first surface layer model M2 and the second surface layer model M3 are based on aluminum. That is, the parameters of the first surface layer model M2 and the second surface layer model M3 are based on values ​​based on the cover body 5 and the terminal portion 30. In other words, analytical model M imitates internal resin plate portion 13 of resin material 10 to which protrusion 55 of lid 5 and terminal plate portion 32 of terminal portion 30 are bonded to the front and back sides, respectively.

[0025] FIG. 3 shows a side surface M1S of the intermediate layer model M1, a side surface M2S of the first surface layer model M2, and a side surface M3S of the second surface layer model M3. The side surface M2S of the first surface layer model M2 is aligned on the same plane as the side surface M1S of the intermediate layer model M1. On the other hand, the side surface M3S of the second surface layer model M3 protrudes from the side surface M1S of the intermediate layer model M1. The second surface layer model M3 has a protruding portion M3T protruding from the side surface M1S of the intermediate layer model M1. That is, the second surface layer model M3 is made of a metal material having a portion protruding from the resin material, unlike the structure related to the external terminal 6 described above.

[0026] FIG. 4 is a diagram showing stress distribution obtained by performing CAE analysis using the analysis model M shown in FIG. 3. FIG. 4 shows the stress distribution in the intermediate layer model M1 when the temperature is changed for the analysis model M. Each member expands and contracts in response to temperature changes. The degree of expansion and contraction differs between metal materials and resin materials. Therefore, stress acts on the intermediate layer model M1, which is made of resin material, due to the difference in the degree of expansion and contraction between the metal material and the resin material.

[0027] The stress distribution is shown by the density of dots or diagonal lines. The higher the density of dots or diagonal lines, the higher the stress. Areas where the stress is relatively low are shown by dots. Areas where the stress is higher than the range shown by dots are shown by diagonal lines. That is, the diagonal lined area H is an area where high stress was confirmed.

[0028] From FIG. 4, it can be seen that the region H is biased toward the second main surface M1B side rather than the first main surface M1A side on the side M1S of the intermediate layer model M1. The second main surface M1B is the surface to which the second surface layer model M3 having a protruding portion M3T protruding from the side surface M1S of the intermediate layer model M1 is bonded. From this, it was confirmed that in a resin material having metal materials bonded to the front and back sides, when a metal material having a portion protruding from the side surface is bonded, high stress tends to concentrate and act near the bonding surface with the protruding metal material. And, it was confirmed that when the side surface of the metal material does not protrude from the side surface of the resin material, the stress acting on the resin material is alleviated compared to when it protrudes.

[0029] As described above, in this embodiment, both side surface 57 of protrusion 55 of lid 5 and side surface 34 of terminal plate portion 32 of terminal portion 30 are designed not to protrude beyond side surface 16 of internal resin plate portion 13. This prevents high stress from acting on internal resin plate portion 13 in the event of a temperature change in battery 1 of this embodiment, thereby preventing damage to resin material 10.

[0030] In addition, in practice, it is difficult to align both the side surface 57 of the protruding portion 55 of the lid body 5 and the side surface 34 of the terminal plate-shaped portion 32 of the terminal portion 30 on the same plane as the side surface 16 of the internal resin plate-shaped portion 13. For this reason, it is preferable to form the side surface 16 of the internal resin plate-shaped portion 13 so as to protrude from at least one of the side surface 57 of the protruding portion 55 of the lid body 5 and the side surface 34 of the terminal plate-shaped portion 32 of the terminal portion 30. This makes it possible to more reliably suppress the application of high stress to the side of the internal resin plate-shaped portion 13 to which the one metal material is joined. In other words, it is possible to more reliably suppress damage to the resin material 10. In addition, the side surface 16 of the internal resin plate-shaped portion 13 may be protruded from both the side surface 57 of the protruding portion 55 of the lid body 5 and the side surface 34 of the terminal plate-shaped portion 32 of the terminal portion 30. This makes it possible to more reliably suppress the application of high stress to the entire internal resin plate-shaped portion 13. In other words, it is possible to more reliably suppress damage to the resin material 10.

[0031] Moreover, the resin material 10 is a base resin blended with a filler. The main orientation direction of the filler in the internal resin plate-shaped portion 13 is preferably parallel to the joint surface of the internal resin plate-shaped portion 13 with the metal material. In this embodiment, the main orientation direction of the filler in the internal resin plate-shaped portion 13 is parallel to the convex inner surface 52A of the convex portion 55 of the lid 5 and the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30.

[0032] In general, in a resin material containing a filler, the orientation direction of the filler tends to improve the mechanical strength more than the direction intersecting the orientation direction. In addition, in the resin material, when a temperature change occurs, a pulling force by the metal material acts near the joint surface with the metal material having a different linear expansion coefficient. The direction of the force is generally parallel to the joint surface of the resin material with the metal material. Therefore, by having the main orientation direction of the filler in the internal resin plate portion 13 parallel to the joint surface of the internal resin plate portion 13 with the metal material, damage to the resin material 10 can be suppressed.

[0033] Specifically, the average orientation direction of the filler blended in the internal resin plate-shaped portion 13 is preferably at an angle of 20° or less with respect to the surface of the metal material bonded 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 alleviated 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 lid body 5 and the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30 are parallel. In other words, the angle of the average orientation direction of the filler in the internal resin plate-shaped portion 13 with respect to the convex inner surface 52A of the convex portion 55 of the lid body 5 is the same as the angle of the average orientation direction of the filler in the internal resin plate-shaped portion 13 with respect to the first main surface 35 of the terminal plate-shaped portion 32 of the terminal portion 30.

[0034] Even when the inner surface 52A of the protrusion 55 of the lid 5 and the first main surface 35 of the terminal plate-like portion 32 of the terminal portion 30 are not parallel to each other, the average orientation direction of the filler in the internal resin plate-like portion 13 is preferably 20° or less relative to either of them. The smaller the angle of the average orientation direction of the filler contained in the internal resin plate-like portion 13 with respect to the surface of the metal material joined to the internal resin plate-like portion 13, the more preferable it tends to be. Therefore, it is more preferable that the angle of the average orientation direction of the filler contained in the internal resin plate-like portion 13 with respect to the surface of the metal material joined to the internal resin plate-like portion 13 is 15° or less.

[0035] In this embodiment, the angle between the average orientation direction of the filler 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 of a cross section intersecting with the surface of the metal material to which the internal resin plate-shaped portion 13 is joined, the angle of the longitudinal direction of the filler with respect to the surface reference line of the metal material is calculated for a plurality of fillers, and the angle can be obtained by the arithmetic average. The surface reference line of the metal material in the CT image can be the average line of any five points extracted from the surface of the metal material.

[0036] In addition, it is preferable that a fine uneven shape is formed on the surface of the metal material to be bonded to the resin material 10, and the resin material 10 is embedded in the uneven shape to form a fine anchor structure. The fine uneven shape can be formed by irradiating the surface of the metal material with a laser and roughening the surface. In the region where such an anchor structure is formed, the bonding strength between the resin material 10 and the metal material can be increased. In other words, it is possible to prevent the resin material 10 from peeling off from the metal material.

[0037] Such a concave-convex shape is preferably formed in at least a part of the region of the convex inner surface 52A of the convex portion 55 of the lid 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 lid body 5. In addition, the concave-convex shape is preferably formed in at least a part of the region 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, the concave-convex shape is preferably formed on both the convex inner surface 52A of the convex portion 55 of the lid body 5 and the first main surface 35 of the terminal plate-shaped portion 32. This is because it is possible to suppress both 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.

[0038] In this embodiment, even if the bonding strength between the internal resin plate part 13 and the metal material is high, high stress is prevented from acting on the internal resin plate part 13 when a temperature change occurs. This prevents the internal resin plate part 13 from being damaged. In other words, both peeling of the internal resin plate part 13 and damage to the internal resin plate part 13 are prevented when a temperature change occurs.

[0039] As described above in detail, the battery 1 according to the present embodiment includes a battery case 2, a terminal portion 30, and a resin material 10. The battery case 2 includes a lid body 5. The lid body 5 is formed with a through hole 53. The terminal portion 30 is provided through the through hole 53 and is provided from the inside to the outside of the battery case 2. The resin material 10 is provided between the lid body 5 and the terminal portion 30 of the battery case 2. The resin material 10 is joined to the lid body 5 and the terminal portion 30. The terminal portion 30 includes a columnar portion 31 and a terminal plate portion 32. At least a portion of the columnar portion 31 is located inside the through hole 53. The terminal plate portion 32 is located inside the battery case 2 and has a shape that is wider than the through hole 53 along the inner surface 52 of the lid body 5. The resin material 10 includes a tubular portion 11 and an internal resin plate 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 portion 13 is located between the inner surface 52 of the lid body 5 and the terminal plate portion 32. The inner surface 52A of the protruding portion to which the internal resin plate portion 13 is joined protrudes toward the inside of the battery case 2, compared with the inner surface 52B of the non-protruding portion, which is farther from the through hole 53 than the inner surface 52A of the protruding portion, to provide a protruding portion 55. The side surface 57 of the protruding portion 55 and the side surface 34 of the terminal plate portion 32 do not protrude beyond the side surface 16 of the internal resin plate portion 13. This can suppress the stress acting on the internal resin plate portion 13 when a temperature change occurs. This realizes a battery 1 in which the resin material 10 is less likely to be damaged.

[0040] The present embodiment and examples are merely illustrative and do not limit the disclosed technology in any way. Therefore, the disclosed technology can be naturally improved and modified in various ways without departing from the spirit and scope of the invention.

[0041] For example, the region where the fine anchor structure is formed can be adjusted as appropriate. That is, for example, fine unevenness may be formed in the entire region of the surface of the lid body 5 and the terminal portion 30 where the resin material 10 is bonded. Also, for example, fine unevenness may be formed in the entirety of at least one of the inner surface 52A of the convex portion 55 and the first main surface 35 of the terminal plate-like portion 32. Also, for example, when fine unevenness is formed in at least a part of the inner surface 52A of the convex portion 55 and the first main surface 35 of the terminal plate-like portion 32, it is preferable that the region where the unevenness is formed is a continuous region surrounding the through hole 53. This is because the sealing property of the battery case 2 can be maintained at a high level.

[0042] Also, for example, the side surface 57 of the protrusion 55 may be provided so as to surround the opening of the through hole 53 on the inner surface 52 side of the lid body 5, and the portion farther from the through hole 53 than the protrusion 55 may have any shape. Specifically, for example, the lid body 8 shown in FIG. 5 may be adopted. The lid body 8 is formed with a through hole 83 penetrating from the outer surface 81 to the inner surface 82. On the inner surface 82 side of the lid body 5, a continuous annular groove portion 86 is formed so as to surround the opening of the through hole 83. As a result, a protrusion 85 is provided inside the groove portion 86, that is, on the through hole 83 side of the groove portion 86. The internal resin plate-shaped portion 13 of the resin material 10 is joined to the protrusion inner surface 82A of the protrusion 85. Even in the lid body 8 having such a shape, the protrusion inner surface 82A protrudes toward the inside of the battery case 2 compared to the bottom surface 82B of the groove portion 86 which is farther from the through hole 83 than the protrusion inner surface 82A. Even when the lid 8 is used, it is sufficient that the side surface 87 of the protrusion 85 does not protrude beyond the side surface 16 of the internal resin plate-shaped portion 13 .

[0043] Also, for example, the external terminal 6 may be provided on the box body 4 of the battery case 2. Also, for example, the terminal portion 30 may be composed of one member, or may be composed by connecting a plurality of members. Also, for example, the cross-sectional shape of each member relating to the external terminal 6 described above, which is perpendicular to the axial direction of the through hole 83, is rectangular. However, the shape is not limited to a rectangular shape, and for example, a round shape may be adopted.

[0044] For example, in the above, the configuration of the external terminal 6 side, which is the positive electrode, has been specifically described. However, the external terminal 7 side, which is the negative electrode, can also have a similar structure. For the external terminal 7 side, which is the negative electrode, a material different from that of the positive electrode side can be used as appropriate. For example, in the configuration of the external terminal 7 side, a copper material can be used as a terminal part where the inside side of the battery case 2 is connected to the negative electrode plate 3B. Furthermore, the technology disclosed herein may be applied to only one of the configuration of the external terminal 6 side, which is the positive electrode, and the configuration of the external terminal 7 side, which is the negative electrode.

[0045] The above-disclosed technology also includes the following means 1 to 3. [Means 1] 2. The battery of claim 1, A battery in which a side surface of the resin plate portion protrudes beyond at least one of a side surface of the protrusion and a side surface of the terminal plate portion.

[0046] [Means 2] A battery according to claim 1 or the above means 1, The resin material is obtained by blending a filler with a base resin, A battery in which a main orientation direction of the filler in the resin plate-like portion is parallel to the inner joint surface and to a joint surface of the terminal plate-like portion with the resin plate-like portion.

[0047] [Means 3] A battery according to claim 1, any one of the above means 1 or means 2, A battery in which a fine uneven shape is formed in the opposing area of ​​the resin plate portion in at least one of the convex portion and the terminal plate portion, and an anchor structure is formed by the resin material penetrating into the uneven shape. [Explanation of symbols]

[0048] 1 battery 2 Battery case 5, 8 Lid 10 Resin material 11 Tubular part 13 Internal resin plate part 16 Side 30 Terminal section 31 Columnar part 32 Terminal plate part 34 Side 52, 82 Inside 52A, 82A Convex inner surface (joint inner surface) 52B Non-convex inner surface 82B Bottom 53, 83 Through holes 54 Wall 55, 85 convex part 57, 87 Side

Claims

1. A battery having a battery case having a through hole formed therein, a terminal portion provided on the inside and outside of the battery case by penetrating the through hole, and a resin material provided between the battery case and the terminal portion and joined thereto, the terminal portion has a columnar portion at least a portion of which is located inside the through hole, and a terminal plate portion which is located inside the battery case and has a shape that extends larger than the through hole along an inner surface of the battery case, the resin material has a tubular portion located between a wall surface of the through hole and the columnar portion, and a resin plate portion located between an inner surface of the battery case and the terminal plate portion, a convex portion is provided on a periphery of the through hole on the inner surface side of the battery case by a joint inner surface to which the resin plate-like portion is joined protruding toward the inside of the battery case compared to a portion farther from the through hole than the joint inner surface, A battery in which neither the side surface of the protrusion nor the side surface of the terminal plate portion protrudes beyond the side surface of the resin plate portion.

2. 2. The battery of claim 1 , A battery in which a side surface of the resin plate portion protrudes beyond at least one of a side surface of the protrusion and a side surface of the terminal plate portion.

3. 2. The battery of claim 1 , The resin material is obtained by blending a filler with a base resin, A battery in which a main orientation direction of the filler in the resin plate-like portion is parallel to the inner joint surface and to a joint surface of the terminal plate-like portion with the resin plate-like portion.

4. A battery according to any one of claims 1 to 3, A battery in which a fine uneven shape is formed in the opposing area of ​​the resin plate portion in at least one of the convex portion and the terminal plate portion, and an anchor structure is formed by the resin material penetrating into the uneven shape.

Images