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 portion 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 joined with a resin material at a through-hole formed in the battery case, as disclosed in Patent Document 1, for example. Patent Document 1 describes that the resin material insulates the battery case from the terminal while filling the gap between them, thereby sealing 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 described above is a different material from the battery case and terminals. That is, the linear expansion coefficient of the resin material is different from that of the battery case and terminals. Therefore, when the temperature of the battery changes, tensile stress may be generated in the resin material near the bonding interface with other components. Depending on the degree and frequency of the action of this tensile stress, the resin material may be damaged. Furthermore, depending on the degree of damage to the resin material, problems such as a decrease in the sealing ability of the battery may occur.

[0005] An object of the present disclosure is to provide a battery in which the resin material joined to 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 is a battery having a battery case with 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, wherein the terminal portion has a columnar portion at least a portion of which is located inside the through hole; It is integral with the columnar part Located inside the battery case And The battery has a terminal plate-like portion that extends along the inner surface of the battery case and is wider than the through hole, and the resin material has a tubular portion located between the wall surface of the through hole and the columnar portion, and a resin plate-like portion located between the inner surface of the battery case and the terminal plate-like portion, and a convex portion is formed on the periphery of the through hole on the inner surface side of the battery case, as the joining inner surface to which the resin plate-like 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 both the side surface of the convex portion and the side surface of the terminal plate-like portion do not protrude beyond the side surface of the resin plate-like 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 changes, the difference in the degree of expansion and contraction suppresses the stress acting on the resin material, and therefore the resin material is less likely to be damaged. [Effects of the Invention]

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

[0009] [Figure 1] FIG. 1 is a perspective view of a battery according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing the structure of an external terminal portion of a battery. [Figure 3] FIG. 10 is a diagram showing an analytical model in which a resin material is bonded to a metal. [Figure 4] FIG. 10 is a diagram showing a stress distribution obtained by stress analysis using an analytical model. [Figure 5] FIG. 10 is a cross-sectional view showing a modified example of the structure of the external terminal portion. DETAILED DESCRIPTION OF THE INVENTION

[0010] This embodiment embodies the disclosed technology in a battery 1 shown in Fig. 1. The battery 1 comprises an electrode assembly 3 housed in a battery case 2. The electrode assembly 3 is formed 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, the battery case 2 also contains an electrolyte.

[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 and 7. When viewed from the outside of the battery 1, terminal surfaces 6A and 7A and resin materials 10 and 20 are visible at the locations of the external terminals 6 and 7. The external terminal 6 is a positive terminal, and the external terminal 7 is a negative terminal.

[0012] The structure of the location of the external terminal 6 will be explained 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 interior of the battery case 2. Therefore, the terminal portion 30 is provided across the inside and outside of the battery case 2. Furthermore, a resin material 10 is provided between the lid body 5 and the terminal portion 30.

[0013] The lid 5 is made of a conductive metal material. In this embodiment, the lid 5 is made of aluminum. At the location of the external terminal 6, the lid 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 5 has a protrusion 55 at a location located on the periphery of the through-hole 53 inside the battery case 2 (i.e., on the inner surface 52 side).

[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 from the through-hole 53 than the convex portion 55. The portion that is farther from the through-hole 53 than the convex portion 55 is shown as a non-convex portion 56 in FIG. 2. Furthermore, of the inner surface 52, the portion at the convex portion 55 is shown as a convex inner surface 52A, and the portion at the non-convex portion 56 is shown as a non-convex inner surface 52B. In this embodiment, the convex inner surface 52A is the end face of the convex portion 55 in the protruding direction.

[0015] The inner surface of the convex portion 52A protrudes further toward the inside of the battery case 2 than the inner surface of the non-convex portion 52B. In other words, 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 inner surface of the convex portion 52A and the inner surface of the non-convex portion 52B. The opening of the through-hole 53 on the inside of the battery case 2 is located on the inner surface of the convex portion 52A. In other words, the through-hole 53 is provided in the area 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 portion 32 is located closer to the interior of the battery case 2 than the columnar portion 31. The terminal plate portion 32 is connected to the columnar portion 31. Inside the battery case 2, the terminal plate portion 32 has a shape that is wider than the columnar portion 31 and extends along the inner surface 52A of the convex portion. Furthermore, the terminal plate portion 32 in this embodiment has a shape that is wider than the through hole 53. FIG. 2 shows the side surface 34, first main surface 35, and second main surface 36 of the terminal plate portion 32. The first main surface 35 of the terminal plate portion 32 is the surface of the terminal plate portion 32 that faces the inner surface 52 of the lid 5. The second main surface 36 of the terminal plate portion 32 is the back surface of the first main surface 35.

[0018] The current collecting portion 33 is provided closer to the interior of the battery case 2 than the terminal plate portion 32. The terminal plate portion 32 is connected to the terminal plate 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 portion 32. In this embodiment, the current collecting portion 33 is formed thinner than the terminal plate 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 blended into 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 of this embodiment contains a filler in the base resin, it has higher mechanical strength than one that does not contain 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 the 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 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 portion 13 is located closer to the interior of the battery case 2 than the tubular portion 11. The internal resin plate portion 13 is connected to the tubular portion 11. The internal resin plate portion 13 extends wider than the through-hole 53 inside the battery case 2. FIG. 2 shows the side surface 16, first main surface 17, and second main surface 18 of the internal resin plate portion 13. The first main surface 17 of the internal resin plate portion 13 faces the inner surface 52 of the lid 5. The second main surface 18 of the internal resin plate portion 13 is the backside of the first main surface 17. The second main surface 18 of the internal resin plate portion 13 faces the first main surface 35 of the terminal plate portion 32. The internal resin plate portion 13 is located between the terminal plate portion 32 and a convex inner surface 52A of the inner surface 52 of the lid 5.

[0022] The resin material 10 is formed by holding the lid body 5 and the terminal portion 30 in a predetermined positional relationship, filling the gap between them with molten resin, 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 portion 13 is bonded to the protrusion 55 of the lid 5 and the terminal plate portion 32 of the terminal 30. Specifically, the first main surface 17 of the internal resin plate portion 13 is bonded to the inner surface 52A of the protrusion 55 of the lid 5. Therefore, the inner surface 52A of the protrusion is the bonding inner surface of the inner surface 52 to which the internal resin plate portion 13 of the resin material 10 is bonded. The second main surface 18 of the internal resin plate portion 13 is bonded to the first main surface 35 of the terminal plate portion 32 of the terminal 30. That is, the internal resin plate portion 13 is sandwiched between metals having linear expansion coefficients different from those of the internal resin plate portion 13 and bonded to those metals. In this embodiment, the side surface 57 of the protrusion 55 of the lid 5 and the side surface 34 of the terminal plate portion 32 of the terminal 30 do not protrude beyond the side surface 16 of the internal resin plate portion 13. The shapes of the cover 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 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 metal sheets. 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 material in which PPS resin is used as the base resin and glass is used as a filler. That is, the parameters of the intermediate layer model M1 are based on values ​​corresponding to the resin material 10. The parameters of the first surface layer model M2 and the second surface layer model M3 are based on values ​​corresponding to aluminum. That is, the parameters of the first surface layer model M2 and the second surface layer model M3 are based on values ​​corresponding to the lid body 5 and the terminal portion 30. That is, analytical model M is a replica of 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 flush with 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 further than the side surface M1S of the intermediate layer model M1. The second surface layer model M3 has a protruding portion M3T that protrudes further than the side surface M1S of the intermediate layer model M1. In other words, the second surface layer model M3 is made of a metal material with a portion protruding further than the resin material, unlike the structure of 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 of the analysis model M is changed. Each component 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 indicated by the density of dots or diagonal lines. The higher the density of dots or diagonal lines, the higher the stress. Areas with relatively low stress are indicated by dots. Areas with higher stress than the range indicated by dots are indicated by diagonal lines. In other words, the diagonally shaded area H is an area where high stress was confirmed.

[0028] From Figure 4, it can be seen that region H is biased toward the second principal surface M1B side rather than the first principal surface M1A side on the side M1S of the intermediate layer model M1. The second principal surface M1B is the surface to which the second surface layer model M3, which has a protruding portion M3T protruding beyond 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, when a metal material having a portion protruding beyond the side surface is bonded, high stress tends to concentrate and act near the bonded surface with the protruding metal material. Furthermore, it was confirmed that when the side surface of the metal material does not protrude beyond 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, the side surface 57 of the protrusion 55 of the lid 5 and the side surface 34 of the terminal plate portion 32 of the terminal section 30 do not protrude beyond the side surface 16 of the internal resin plate portion 13. This prevents high stress from acting on the internal resin plate portion 13 when a temperature change occurs in the battery 1 of this embodiment, thereby preventing damage to the resin material 10.

[0030] Furthermore, in practice, it is difficult to align both the side surface 57 of the protrusion 55 of the lid 5 and the side surface 34 of the terminal plate portion 32 of the terminal unit 30 flush with the side surface 16 of the internal resin plate portion 13. Therefore, it is preferable to form the side surface 16 of the internal resin plate portion 13 so that it protrudes beyond at least one of the side surface 57 of the protrusion 55 of the lid 5 and the side surface 34 of the terminal plate portion 32 of the terminal unit 30. This more reliably prevents high stress from acting on the side of the internal resin plate portion 13 to which the metal material is bonded. In other words, damage to the resin material 10 can be more reliably prevented. Alternatively, the side surface 16 of the internal resin plate portion 13 may protrude beyond both the side surface 57 of the protrusion 55 of the lid 5 and the side surface 34 of the terminal plate portion 32 of the terminal unit 30. This more reliably prevents high stress from acting on the entire internal resin plate portion 13. In other words, damage to the resin material 10 can be more reliably prevented.

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

[0032] Generally, in resin materials containing fillers, the orientation direction of the filler tends to improve mechanical strength more than the direction intersecting the orientation direction. Furthermore, when a temperature change occurs in a resin material, a pulling force is exerted by the metal material near the joint surface with a metal material having a different linear expansion coefficient. The direction of this force is generally parallel to the joint surface of the resin material with the metal material. Therefore, by aligning 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 portion 13 preferably forms an angle of 20° or less with respect to the surface of the metal material bonded to the internal resin plate portion 13. This is because the stress acting on the internal resin plate portion 13 when a temperature change occurs can be alleviated to a degree that appropriately suppresses damage to the internal resin plate portion 13. In this embodiment, the convex inner surface 52A of the convex portion 55 of the lid 5 and the first main surface 35 of the terminal plate portion 32 of the terminal unit 30 are parallel. In other words, the angle of the average orientation direction of the filler in the internal resin plate portion 13 with respect to the convex inner surface 52A of the convex portion 55 of the lid 5 is the same as the angle of the average orientation direction of the filler in the internal resin plate portion 13 with respect to the first main surface 35 of the terminal plate portion 32 of the terminal unit 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 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 portion 13 is preferably 20° or less relative to either of them. The smaller the angle between the average orientation direction of the filler contained in the internal resin plate portion 13 and the surface of the metal material joined to the internal resin plate portion 13, the more preferable it tends to be. Therefore, it is more preferable that the angle between the average orientation direction of the filler contained in the internal resin plate portion 13 and the surface of the metal material joined to the internal resin plate portion 13 be 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 multiple fillers, and the angle can be obtained by taking 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] Furthermore, it is preferable that a fine uneven shape be formed on the surface of the metal material to be bonded to the resin material 10, and that the resin material 10 penetrate into 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 to roughen 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, peeling of the resin material 10 from the metal material can be suppressed.

[0037] Such an uneven shape is preferably formed on at least a partial region of the convex-portion inner surface 52A of the convex portion 55 of the lid body 5, which faces the internal resin plate portion 13. This is because peeling of the internal resin plate portion 13 from the convex portion 55 of the lid body 5 can be suppressed. Furthermore, the uneven shape is preferably formed on at least a partial region of the first main surface 35 of the terminal plate portion 32 of the terminal unit 30, which faces the internal resin plate portion 13. This is because peeling of the internal resin plate portion 13 from the terminal plate portion 32 can be suppressed. Furthermore, the uneven shape is preferably formed on both the convex-portion inner surface 52A of the convex portion 55 of the lid body 5 and the first main surface 35 of the terminal plate portion 32. This is because peeling of the internal resin plate portion 13 from the convex portion 55 and the first main surface 35 of the terminal plate portion 32 can be suppressed.

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

[0039] As described above in detail, the battery 1 according to this embodiment includes a battery case 2, a terminal portion 30, and a resin material 10. The battery case 2 includes a lid 5. A through-hole 53 is formed in the lid 5. The terminal portion 30 penetrates the through-hole 53 and is provided across the inside and outside of the battery case 2. The resin material 10 is provided between the lid 5 and the terminal portion 30 of the battery case 2. The resin material 10 is bonded to the lid 5 and the terminal portion 30. The terminal portion 30 also 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 extends along the inner surface 52 of the lid 5, wider than the through-hole 53. 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 5 and the terminal plate portion 32. A convex portion 55 is formed around the periphery of the through-hole 53 on the inner surface 52 side of the lid 5. The convex portion inner surface 52A, to which the internal resin plate portion 13 is joined, protrudes toward the inside of the battery case 2 compared to the non-convex portion inner surface 52B, which is farther from the through-hole 53 than the convex portion inner surface 52A. The side surface 57 of the convex 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 reduces stress acting on the internal resin plate portion 13 when temperature changes occur. This results in 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 naturally be 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 irregularities may be formed on the entire surface of the lid body 5 and the terminal portion 30 in the region where the resin material 10 is bonded. Alternatively, for example, fine irregularities may be formed on the entire surface of at least one of the inner surface 52A of the convex portion 55 and the first main surface 35 of the terminal plate portion 32. Furthermore, when fine irregularities are formed on at least a portion of the inner surface 52A of the convex portion 55 and the first main surface 35 of the terminal plate portion 32, it is preferable that the region where the irregularities are formed be a continuous region surrounding the through-hole 53. This is because the battery case 2 can be kept highly airtight.

[0042] Furthermore, for example, it is sufficient that 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 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 employed. The lid body 8 has a through-hole 83 formed therethrough from the outer surface 81 to the inner surface 82. A continuous annular groove 86 is formed on the inner surface 82 side of the lid body 5 so as to surround the opening of the through-hole 83. As a result, a protrusion 85 is provided inside the groove 86, i.e., on the through-hole 83 side of the groove 86. The internal resin plate portion 13 of the resin material 10 is joined to the protrusion inner surface 82A of the protrusion 85. Furthermore, 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 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 portion 13 .

[0043] For example, the external terminal 6 may be provided on the box body 4 of the battery case 2. For example, the terminal portion 30 may be composed of a single member, or may be composed of multiple members connected together. 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 square. However, the shape is not limited to a square, and a round shape, for example, may also be used.

[0044] Furthermore, for example, the configuration of the external terminal 6 side, which is the positive electrode, has been specifically described above. 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 the terminal portion where the interior 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, or the configuration of the external terminal 7 side, which is the negative electrode.

[0045] The above-mentioned disclosed technology also includes the following means 1 to 3. [Means 1] 10. The battery of claim 1, A battery in which the side surface of the resin plate portion protrudes beyond at least one of the side surface of the protrusion and the side surface of the terminal plate portion.

[0046] [Means 2] The battery according to claim 1 or the above means 1, The resin material is obtained by blending a filler into a base resin, A battery in which the main orientation direction of the filler in the resin plate portion is parallel to the inner joint surface and the joint surface of the terminal plate portion with the resin plate 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 facing area of ​​the resin plate portion on 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 16 Side 30 Terminal section 31 Columnar part 32 Terminal plate part 34 Side 52, 82 inner surface 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 passing through 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 integral with the columnar portion, is located inside the battery case, and has a shape which extends larger than the through hole along the 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 at a periphery of the through hole on the inner surface side of the battery case, by a joining 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 joining 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. 10. The battery of claim 1, A battery in which the side surface of the resin plate portion protrudes beyond at least one of the side surface of the protrusion and the side surface of the terminal plate portion.

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

4. The battery according to any one of claims 1 to 3, A battery in which a fine uneven shape is formed in the facing area of ​​the resin plate portion on 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