Battery and method for manufacturing the same

Abstract

To provide a battery having a terminal part of an easy-to-manufacture structure having a contact part of inner and outer terminal members inside a sealing resin, and to provide its manufacturing method.SOLUTION: A battery according to the present disclosure includes a power generation element and an exterior body 5, a terminal portion 7 is provided in a part of the exterior body 5, an external terminal member 15 exposed to the outside at the terminal portion 7, and an internal terminal member 16 connected to the power generation element and made of a metal different from that of the external terminal member 15. The external contact plate portion 24 and the internal contact plate portion 16 have narrow portions formed at the same position, and in the terminal portion 7, the through hole 17 is closed by the sealing resin 11, and inside the sealing resin 11, the external contact plate portion 18 and the internal contact plate portion 24 are overlapped with their narrow portions aligned with each other.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] A battery generally has a configuration in which a power generating element is housed in an exterior body. A terminal portion for connecting the power generating element to the outside is provided in a part of the exterior body. The space between the exterior body and the terminal member in the terminal portion is sealed with an insulator. Patent Document 1 also describes a battery with such a structure. In the battery of Patent Document 1, one of the positive and negative terminal portions has a joint between two types of metal members inside the sealed insulator. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-58215 Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned conventional technologies have a problem in that the structure of the terminal portion is complicated. This is because two types of metal members are joined inside the sealing insulator. In the case of the battery of Patent Document 1, the joint has a fitting structure of two types of metal members. This makes the manufacturing process complicated. For example, this is because it requires multiple steps such as a crimping step, a welding step, and an ultrasonic joining step.

[0005] An object of the present disclosure is to provide a battery having a terminal portion with an easy-to-manufacture structure in which the contact points between the internal and external terminal members are located inside the sealing resin, as well as a method for manufacturing the battery. [Means for solving the problem]

[0006] A battery in one aspect of the disclosed technology has a power generating element and an outer casing that houses the power generating element, and a terminal portion for connecting the power generating element to the outside is provided in a portion of the outer casing, and has an external terminal member exposed to the outside at the terminal portion, and an internal terminal member that is connected to the power generating element and is made of a different metal type than the external terminal member, the external terminal member has an external contact plate portion on one side that is a contact surface with the internal terminal member, and the internal terminal member has an internal contact plate portion on one side that is a contact surface with the external terminal member, the external contact plate portion and the internal contact plate portion have the same in-plane shape with narrow portions formed in the same position, the terminal portion has a through hole in the outer casing that is closed with sealing resin, and the external contact plate portion and the internal contact plate portion are overlapped inside the sealing resin with their narrow portions aligned and their contact surfaces in contact.

[0007] In another aspect of the disclosed technology, a method for manufacturing a battery includes a power generating element and an outer casing that houses the power generating element, and a terminal portion provided in a portion of the outer casing for connecting the power generating element to the outside. The method uses an outer casing that has a through hole drilled at the location that will become the terminal portion, an external terminal member that is exposed to the outside at the terminal portion, and an internal terminal member that is connected to the power generating element and is made of a different metal type from the external terminal member. The external terminal member has an external contact plate portion on one side that is a contact surface with the internal terminal member, and the internal terminal member has an internal contact plate portion on one side that is a contact surface with the external terminal member. The external contact plate portion and the internal contact plate portion have the same in-plane shape with narrow portions formed in the same position. The external terminal member and the internal terminal member are overlapped with the external contact plate portion and the internal contact plate portion aligned with each other and with their contact surfaces pressed against each other, thereby closing the through hole and forming a sealing resin that encases the external contact plate portion and the internal contact plate portion.

[0008] In the battery according to the disclosed technology, the external terminal member and the internal terminal member are in contact with each other at the contact plate portions of the terminal section, and the contact points are enclosed in a sealing resin. The sealing resin also seals the through holes in the exterior body. The terminal members are fixed to each other and to the exterior body by the sealing resin. The narrow portions of the contact plate portions are formed by providing through holes or notched recesses in the contact plate portions. The sealing resin also penetrates into the through holes or notched recesses. This ensures that the terminal members are firmly fixed by the sealing resin.

[0009] This structure can be realized through a relatively simple process of overlapping the external and internal contact plates and forming the sealing resin. Because the contact surfaces are pressed together during the formation of the sealing resin, there is good continuity between the external and internal terminal members. When overlapping the external and internal contact plates, the presence of narrow portions of the contact plates serves as a guide for positioning. Because no welding process, ultrasonic bonding process, or the like is required, no alloy layer, intermetallic compound layer, or the like exists at the contact interface between the external and internal contact plates. Therefore, corrosion is less likely to occur at the contact points.

[0010] In the battery according to the present disclosure, the external terminal member has an exposed portion exposed to the outside and an external connecting portion connecting the external contact plate portion and the exposed portion, and the internal terminal member has an internal connecting portion connecting the internal contact plate portion and the power generating element, and the external contact plate portion is preferably located on the power generating element side relative to the internal contact plate portion, and the end of the external contact plate portion opposite the external connecting portion contacts the internal connecting portion, and the end of the internal contact plate portion opposite the internal connecting portion contacts the external connecting portion. This configuration provides a large contact area between the two terminal members, which is advantageous for conductivity. Furthermore, it is easy to position the external terminal member and the internal terminal member when overlapping them during the manufacturing process.

[0011] In the battery according to the disclosed technology, it is further desirable that the thickness of the narrow portion of the external contact plate is thinner than the thickness of the remaining portion of the external contact plate, and / or the thickness of the narrow portion of the internal contact plate is thinner than the thickness of the remaining portion of the internal contact plate. The narrow portion can be provided with a fuse function. In this case, the fuse function is more reliable if the thickness of the narrow portion is made thinner. [Effects of the Invention]

[0012] According to the disclosed technique, a battery having a terminal portion with an easy-to-manufacture structure in which the contact points between the inner and outer terminal members are located inside the sealing resin is provided, along with a manufacturing method thereof. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is an external perspective view of a battery according to an embodiment; [Figure 2] FIG. [Figure 3] FIG. 1 is a cross-sectional view (part 1) showing the structure of the negative terminal portion. [Figure 4] FIG. [Figure 5] FIG. 1 is a perspective view (part 1) of an outer terminal member. [Figure 6] FIG. 2 is a perspective view (part 2) of the outer terminal member. [Figure 7] FIG. 2 is a perspective view showing a state in which the inner terminal member and the outer terminal member are combined together. [Figure 8] FIG. 2 is a cross-sectional view (part 2) showing the structure of the negative terminal portion. [Figure 9] 4 is a perspective view showing a portion of the internal terminal member near an internal contact plate portion. FIG. [Figure 10] FIG. 10 is a perspective view (part 1) of a modified example of FIG. [Figure 11] FIG. 10 is a perspective view (part 2) of a modified example of FIG. [Figure 12] FIG. 10 is a perspective view (part 3) of a modified example of FIG. 9. [Figure 13]FIG. 4 is a cross-sectional view of a modified example of FIG. 3. [Figure 14] 10A to 10C are cross-sectional views showing stages in the manufacture of a lid assembly. [Figure 15] FIG. 10 is a cross-sectional view showing the structure of a negative terminal portion according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0014] The appearance of a battery 1 according to this embodiment is shown in FIG. 1. The battery 1 comprises a power generating element 3 housed in an exterior housing 2. The exterior housing 2 has a box 4 and a lid 5. A positive terminal 6 is provided in one portion of the lid 5. The positive terminal 6 is a portion for connecting the positive electrode plate of the power generating element 3 to the outside. A negative terminal 7 is provided in another portion of the lid 5. The power generating element 3 is an electrode laminate. The negative terminal 7 is a portion for connecting the negative electrode plate of the power generating element 3 to the outside. A positive terminal surface 8 is exposed on the positive terminal 6, and a negative terminal surface 9 is exposed on the negative terminal 7. The positive terminal surface 8 and the negative terminal surface 9 are insulated from the lid 5 by sealing resins 10 and 11, respectively.

[0015] The lid assembly 12 of the battery 1 is shown in Figure 2. The lid assembly 12 is formed by attaching a positive electrode terminal member 13 and a negative electrode terminal member 14 to a lid 5. A power generating element 3 is attached near the bottom ends of the positive electrode terminal member 13 and the negative electrode terminal member 14. The battery 1 is formed by storing the power generating element 3 in a box 4 and closing the opening of the box 4 with the lid 5.

[0016] FIG. 3 shows the cross-sectional structure at the position AA in FIG. 2. This shows the cross-sectional structure of the negative terminal portion 7. The upper side in FIG. 3 is the external side of the battery 1, and the lower side is the internal side. Appearing in FIG. 3 are the lid body 5, the sealing resin 11, the external terminal member 15, and the internal terminal member 16. The negative electrode terminal member 14 shown in FIG. 2 is a combination of the external terminal member 15 and the internal terminal member 16. The external terminal member 15 is located closer to the outside of the battery 1 than the internal terminal member 16. The internal terminal member 16 is located closer to the power generating element 3 than the external terminal member 15. In FIG. 3, the portion of the internal terminal member 16 near the bottom end is omitted.

[0017] As shown in FIG. 3, a through-hole 17 is formed in the lid 5 at the position of the negative terminal 7. The through-hole 17 is closed with a sealing resin 11. The sealing resin 11 also insulates the external terminal member 15 and the internal terminal member 16 from the lid 5. The external terminal member 15 and the internal terminal member 16 are members made of different metals. For example, the external terminal member 15 is made of aluminum and the internal terminal member 16 is made of copper.

[0018] The negative electrode terminal member 14, which is a combination of an external terminal member 15 and an internal terminal member 16, is fixed to the lid 5 by the sealing resin 11 at a position where it passes through the through-hole 17. The external terminal member 15 and the internal terminal member 16 are in contact inside the sealing resin 11. A portion of the surface of the external terminal member 15 is not covered by the sealing resin 11 and is exposed to the outside. This exposed portion is the negative terminal surface 9. A portion of the internal terminal member 16 protrudes downward from the sealing resin 11.

[0019] The internal terminal member 16 is shown alone in Figure 4. In Figure 4, the internal terminal member 16 is drawn as seen from diagonally below. The internal terminal member 16 has an internal contact plate portion 18, an electrode connection portion 19, and an internal connection portion 20. The internal contact plate portion 18, the electrode connection portion 19, and the internal connection portion 20 are all plate-shaped portions. The internal contact plate portion 18 is the portion that comes into contact with the external terminal member 15. In Figure 4, a contact surface 21, which is one side of the internal contact plate portion 18, is visible. The contact surface 21 is the surface that comes into contact with the external terminal member 15. The electrode connection portion 19 is the portion that is connected to the electrode plate of the power generating element 3. The internal connection portion 20 is the portion that connects the internal contact plate portion 18 and the electrode connection portion 19.

[0020] Two through holes 22 are formed in the internal contact plate portion 18. The positions between the through holes 22 and the positions outside the two through holes 22 are narrow width portions 23. In other words, the positions of the internal contact plate portion 18 other than the two through holes 22 in the direction connecting the two through holes 22 are narrow width portions 23. The overall shape of the internal contact plate portion 18 is rectangular. The long side direction is parallel to the longitudinal direction of the cover body 5. An internal connection portion 20 is connected to one end of the long side of the internal contact plate portion 18. The internal connection portion 20 is connected to the side of the contact surface 21 of the internal contact plate portion 18. The internal contact plate portion 18 and the internal connection portion 20 are approximately perpendicular. The internal contact plate portion 18 is arranged approximately parallel to the cover body 5 in the negative terminal portion 7 shown in Figure 3.

[0021] The external terminal member 15 alone is shown in Figures 5 and 6. In Figure 5, the external terminal member 15 is drawn as viewed from diagonally below. In Figure 6, the external terminal member 15 is drawn as viewed from diagonally above. The external terminal member 15 has an external contact plate portion 24, an exposed portion 25, and an external communication portion 26. The external contact plate portion 24 and the exposed portion 25 are both plate-shaped portions.

[0022] The external contact plate portion 24 is the portion that comes into contact with the internal terminal member 16. In Figure 6, a contact surface 27, which is one side of the external contact plate portion 24, is visible. The contact surface 27 is the surface that comes into contact with the internal terminal member 16. The exposed portion 25 is the portion of the negative terminal portion 7 that faces the outside of the battery 1. In Figure 6, the negative terminal surface 9 shown in Figures 1 and 2 is visible. The negative terminal surface 9 is one side of the exposed portion 25. The external connecting portion 26 is the portion that connects the external contact plate portion 24 and the exposed portion 25.

[0023] The external contact plate portion 24 has two through holes 28. The position between the through holes 28 is a narrow width portion 29. The overall shape of the external contact plate portion 24 is rectangular. The long side direction is parallel to the longitudinal direction of the lid body 5. The external connecting portion 26 is connected to one end of the long side of the external contact plate portion 24. The external connecting portion 26 is connected to the contact surface 27 side of the external contact plate portion 24. The external contact plate portion 24 and the exposed portion 25 are arranged approximately parallel to the lid body 5 in the negative terminal portion 7 shown in Figure 3. The distance between the external contact plate portion 24 and the exposed portion 25 is greater than the thickness of the internal contact plate portion 18.

[0024] The through holes 22 in the internal contact plate portion 18 and the through holes 28 in the external contact plate portion 24 are the same size. The spacing between the through holes 22 and the spacing between the through holes 28 are also the same. The overall rectangular shape of the internal contact plate portion 18 and the overall rectangular shape of the external contact plate portion 24 are also the same size. The positions of the through holes 22 in the internal contact plate portion 18 and the positions of the through holes 28 in the external contact plate portion 24 are also the same.

[0025] When the external terminal member 15 and the internal terminal member 16 are joined together, as shown in FIG. 7, the internal contact plate portion 18 is inserted between the external contact plate portion 24 and the exposed portion 25. In this state, the internal contact plate portion 18 and the external contact plate portion 24 are pressed against each other. As a result, the internal contact plate portion 18 and the external contact plate portion 24 are overlapped. The through holes 22 and the through holes 28 are overlapped in the same position. The narrow portions 23 and the narrow portions 29 are also overlapped in the same position. In the negative terminal portion 7 shown in FIG. 2 etc., the negative terminal member 14 in this state is fixed to the lid 5 by the sealing resin 11.

[0026] More specifically, the overlapping internal contact plate portion 18 and external contact plate portion 24 are entirely enclosed in sealing resin 11. Furthermore, sealing resin 11 also fills the through holes 22, 28. Therefore, external terminal member 15 and internal terminal member 16 are firmly fixed together simply by being held by sealing resin 11. Sealing resin 11 plays multiple roles: it maintains the overlapping state of internal contact plate portion 18 and external contact plate portion 24, fixes them to lid body 5, and closes through hole 17 in lid body 5.

[0027] Returning to Figure 3, in the negative terminal portion 7, the contact surface 27 of the external contact plate portion 24 and the contact surface 21 of the internal contact plate portion 18 are in contact within the sealing resin 11. The external contact plate portion 24 is located below the internal contact plate portion 18 in Figure 3, that is, on the side of the power generating element 3. An end portion 34 of the external contact plate portion 24 opposite the external connecting portion 26 is in contact with the internal connecting portion 20. An end portion 35 of the internal contact plate portion 18 opposite the internal connecting portion 20 is in contact with the external connecting portion 26. The contact points between the end portion 34 and the internal connecting portion 20 and the contact points between the end portion 35 and the external connecting portion 26 also function as conduction paths between the external terminal member 15 and the internal terminal member 16.

[0028] In this state, as described above, through holes 28 and through holes 22 overlap in the same position. The cross-sectional position shown in FIG. 3 corresponds to the narrow portions 23 and 29 described above in the internal contact plate portion 18 and the external contact plate portion 24. Therefore, through holes 28 and 22 are not shown in FIG. 3. A cross-section at the positions corresponding to through holes 28 and 22 is shown in FIG. 8. The positions shown in FIG. 8 do not function as a conductive path between the internal contact plate portion 18 and the external contact plate portion 24 due to the through holes 28 and 22. The positions of narrow portions 23 and 29 shown in FIG. 3 function as a conductive path. In addition, the two areas outside through holes 28 and 22 also function as conductive paths. The through holes 28 and 22 do not function as conductive paths, but rather as shapes that strengthen the fixation by the sealing resin 11, as described above.

[0029] The internal contact plate portion 18 and the external contact plate portion 24 as a whole have portions where the cross-sectional area of ​​conduction is limited by the through holes 28 and 22. This will be explained with reference to Figure 9. In Figure 9, only the internal contact plate portion 18 is shown, with the external contact plate portion 24 omitted. As mentioned above, only the narrow portion 23 of the internal contact plate portion 18 functions as a conduction path. Therefore, if the overall width of the internal contact plate portion 18 is W0, the total width (W1 + W2 + W3) of the narrow portion 23 is smaller than the overall width W0 by the amount of the through holes 22. The same can be said for the external contact plate portion 24.

[0030] The structure of the narrow width portion 23 and the narrow width portion 29 of the internal contact plate portion 18 and the external contact plate portion 24 is not limited to the pair of two through holes described above. They may be configured as shown in FIG. 10 (only one through hole 22), FIG. 11 (cut recesses 31 on both sides), or FIG. 12 (deep cut recesses 31 on one side). While FIG. 10 shows an example of an elongated hole, this is not limited to an elongated hole. In the examples of FIGS. 11 and 12, the portion other than the cut recesses 31 is the narrow width portion 30. While these figures only show the internal contact plate portion 18, the same applies to the external contact plate portion 24.

[0031] 11 and 12, in which there is only one narrow portion 30, the internal contact plate portion 18 and the external contact plate portion 24 function as a fuse in the conduction path of the battery 1 due to the recessed cutout 31. This is because the narrow portion 30 is likely to melt during an overcurrent. In this manner, in the battery 1 of this embodiment, a fuse structure can be embedded in the sealing resin 11 of the negative terminal portion 7. In this case, in the battery 1 of this embodiment, scattering of spatter is suppressed when the fuse function is activated due to an overcurrent. This is because the narrow portion 30 is enclosed in the sealing resin 11.

[0032] Furthermore, in the fuse structure of the internal contact plate portion 18 and the external contact plate portion 24, it is even more preferable to limit the conduction path not only in the width direction but also in the thickness direction. FIG. 13 shows an example of this. FIG. 13 is a cross-sectional view of a position corresponding to the narrow width portion 30. Unlike FIG. 3, FIG. 13 has thin-walled portions 32 and 33 provided on the internal contact plate portion 18 and the external contact plate portion 24. The thin-walled portions 32 and 33 are the portions of the narrow width portion 30. In the example of FIG. 13, the thickness of the thin-walled portion 33 of the external contact plate portion 24 is thinner than the thickness of the portions of the external contact plate portion 24 other than the thin-walled portion 33. Furthermore, the thickness of the thin-walled portion 32 of the internal contact plate portion 18 is thinner than the thickness of the portions of the internal contact plate portion 18 other than the thin-walled portion 32.

[0033] 13, the presence of the thin-walled portions 32, 33 more reliably ensures the fuse function of the internal contact plate portion 18 and the external contact plate portion 24. It is also possible to provide a thin-walled portion on only one of the internal contact plate portion 18 and the external contact plate portion 24.

[0034] The positive terminal 6 in FIGS. 1 and 2 will now be briefly described. The positive terminal 6 has a through-hole in the lid 5, and the positive terminal member 13 is fixed therein by the sealing resin 10, which is roughly the same structure as the negative terminal 7. However, unlike the negative terminal member 14, the positive terminal member 13 may be an integrated part. In the case of an integrated part, the entire positive terminal member 13 is made of a single metal. In general, the external terminal member 15 and the positive terminal member 13 are made of the same metal. The positive terminal member 13 may also be a combination of an external terminal member and an internal terminal member, like the negative terminal member 14. In this case, the external terminal member and the internal terminal member for the positive terminal member 13 may be made of the same metal type.

[0035] A method for manufacturing the battery 1 will now be described. The method for manufacturing the battery 1 basically involves manufacturing the lid assembly 12 shown in FIG. 2 , attaching the power generating element 3 to it, storing the power generating element 3 attached to the lid assembly 12 in a box 4, and closing the opening of the box 4 with a lid 5. Among these steps, the characteristic part of this embodiment is the manufacturing of the lid assembly 12, and in particular the formation of the negative terminal portion 7.

[0036] The formation of the negative terminal 7 will now be described. It is assumed that the aforementioned lid 5, external terminal member 15, and internal terminal member 16 have been manufactured in advance. A through-hole 17 has already been drilled in the lid 5 at the location that will become the negative terminal 7. To form the negative terminal 7, first, the external terminal member 15 and the internal terminal member 16 are overlapped. Specifically, the internal contact plate portion 18 and the external contact plate portion 24 are overlapped.

[0037] To this end, the internal contact plate portion 18 is inserted between the external contact plate portion 24 and the exposed portion 25. Then, the contact surface 27 of the external contact plate portion 24 is brought into contact with the contact surface 21 of the internal contact plate portion 18, while the through-hole 28 is aligned with the through-hole 22. This results in the state shown in FIG. 7. At this time, the narrow portion 23 of the internal contact plate portion 18 and the narrow portion 29 of the external contact plate portion 24 are overlapping in the same position. A cross-sectional view of this state is shown in FIG. 14. The cover 5 is also shown in FIG. 14. The positional relationship between the external terminal member 15 and the internal terminal member 16 in FIG. 14 is the same as that shown in FIG. 3.

[0038] In this state, as described above, the end 34 of the external contact plate portion 24 is in contact with the internal connecting portion 20, and the end 35 of the internal contact plate portion 18 is in contact with the external connecting portion 26. As a result, the external terminal member 15 and the internal terminal member 16 are positioned relative to each other in the left-right direction in FIG. 14. In this state, by appropriately sliding the external terminal member 15 and the internal terminal member 16 in a direction perpendicular to the plane of the paper in FIG. 14, the narrow portions of both contact plate portions can be placed in the same position. In this case, the through holes 28 and 22 serve as positioning guides, making positioning easy. The same applies to the notched recess 31.

[0039] 14, the contact surface 27 of the outer contact plate 24 and the contact surface 21 of the inner contact plate 18 are pressed against each other. That is, as shown by arrow F in FIG. 14, an upward pulling force is applied to the outer terminal member 15 and a downward pulling force is applied to the inner terminal member 16. This causes the contact surfaces of both contact plates to press against each other.

[0040] While maintaining this pressed-together state, the external terminal member 15 and the internal terminal member 16 are placed at the positions of the through holes 17 of the lid body 5. Then, the sealing resin 11 is formed by molding. The raw resin of the sealing resin 11 envelops the contact positions of both contact plate portions. At this time, the raw resin also penetrates into the through holes 28 and 22. The same is true for the notched recesses 31. However, the raw resin does not penetrate into the gap between the contact surfaces of both contact plate portions, because the contact surfaces of both contact plate portions are pressed against each other. When the raw resin is solidified, the state shown in Figure 3 is obtained.

[0041] In this manner, in this embodiment, the contact points between the external terminal member 15 and the internal terminal member 16 are enclosed within the sealing resin 11. When the sealing resin 11 is molded, the contact surfaces of the external terminal member 15 and the internal terminal member 16 are pressed against each other. Therefore, even if the force pressing the contact surfaces against each other is released after molding of the sealing resin 11, good electrical continuity between the external terminal member 15 and the internal terminal member 16 is maintained. Furthermore, the through holes 28 and 22 of both contact plate portions (as well as the cut recesses) are filled with the solidified sealing resin 11. Therefore, the sealing resin 11 firmly holds the external terminal member 15 and the internal terminal member 16.

[0042] As described above, in this embodiment, the contact surfaces of the external terminal member 15 and the internal terminal member 16 are joined by pressing them together and encasing them in the sealing resin 11. This simplifies the process, eliminating the need for crimping, welding, ultrasonic bonding, and other processes. In particular, the lack of a welding or ultrasonic bonding process means that no thermal history remains at the interface between the two, and no alloy or intermetallic compound layer is formed. This makes the contact points less susceptible to corrosion, resulting in high durability for the battery 1. Furthermore, the fuse structure of the internal contact plate portion 18 and the external contact plate portion 24 can be embedded within the sealing resin 11. This allows the battery 1 of this embodiment to be highly safe against overcurrent.

[0043] The above-described steps of overlapping the external terminal member 15 and the internal terminal member 16 and forming the sealing resin 11 are the same in the modified examples shown in Figures 10 to 13. The positive terminal 6 is formed in substantially the same manner as the negative terminal 7. However, when a single piece is used as the positive terminal member 13, the above-described pressing together is not necessary.

[0044] Another modified example will now be described with reference to Fig. 15. Fig. 15 is a cross-sectional view of the negative terminal portion 7 corresponding to Fig. 3. The difference between the modified example in Fig. 15 and Fig. 3 is the relative positions of the internal contact plate portion 18 and the external contact plate portion 24. In Fig. 3, the internal contact plate portion 18 is on the upper side and the external contact plate portion 24 is on the lower side, but in Fig. 15, the external contact plate portion 24 is on the upper side and the internal contact plate portion 18 is on the lower side.

[0045] 15, a portion of the internal communication portion 20 of the internal terminal member 16 protrudes upward from the internal contact plate portion 18 to form a protrusion 36. Similarly, a portion of the external communication portion 26 of the external terminal member 15 protrudes downward from the external contact plate portion 24 to form a protrusion 37. An end portion 35 of the internal contact plate portion 18 is in contact with the protrusion 37. An end portion 34 of the external contact plate portion 24 is in contact with the protrusion 36.

[0046] The modified example of Figure 15 can also have the fuse structure shown in either Figure 11 or Figure 12. It can also have the thin-walled portions 32, 33 shown in Figure 13. In the manufacturing process, the method of applying force to press the contact surfaces of the two contact plate portions against each other differs. In the example of Figure 3, a pulling force is applied to the external terminal member 15 and the internal terminal member 16, but in the example of Figure 15, a pressing force is applied to the external terminal member 15 and the internal terminal member 16. When overlapping the external terminal member 15 and the internal terminal member 16, the example of Figure 15 does not require the step of inserting the internal contact plate portion 18 between the external contact plate portion 24 and the exposed portion 25.

[0047] As described above in detail, according to this embodiment, the negative electrode terminal member 14 is composed of two members, the external terminal member 15 and the internal terminal member 16. The contact points between them are enclosed in the sealing resin 11. Furthermore, the sealing resin 11 also fills the through holes 28 and 22 of both contact plate members (the same applies to the notched recesses). This realizes a battery 1 in which the negative terminal member 7 can be formed by a relatively simple process of arranging both terminal members in the lid 5 and molding the sealing resin 11. Furthermore, in the manufacturing method, the contact plate members are pressed against each other when molding the sealing resin 11, thereby improving the conductivity of the negative electrode terminal member 14.

[0048] 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. For example, there is no particular limitation on the type of battery used for the power generating element 3. Furthermore, the positive and negative terminals may be reversed, and the features of the above embodiments may be applied to the positive terminal 6 rather than the negative terminal 7. The features of the above embodiments may also be applied to both the negative terminal 7 and the positive terminal 6. [Explanation of symbols]

[0049] 1 Battery 20 Internal communication section 2 Exterior body 21 Contact surface 3 Power generating element 22 Through hole 4 Box body 23 Narrow part 5 Cover 24 External contact plate 6 Positive terminal section 25 Exposed section 7 Negative terminal 26 External connection 8 Positive terminal surface 27 Contact surface 9 Negative terminal surface 28 Through hole 10 Sealing resin 29 Narrow part 11 Sealing resin 30 Narrow part 12 Lid assembly 31 Notched recess 13 Positive electrode terminal member 32 Thin-walled portion 14 negative electrode terminal member 33 thin-walled portion 15 outer terminal member 34 end 16 Internal terminal member 35 End portion 17 Through hole 36 Convex part 18 Internal contact plate portion 37 Convex portion 19 Electrode connection part

Claims

1. A battery comprising a power generating element and an exterior body that houses the power generating element, and a terminal portion for connecting the power generating element to an external device is provided in a part of the exterior body, an external terminal member exposed to the outside at the terminal portion; an internal terminal member connected to the power generating element and made of a different metal from the external terminal member; the external terminal member has an external contact plate portion on one side which is a contact surface with the internal terminal member, the internal terminal member has an internal contact plate portion on one side which is a contact surface with the external terminal member, the external contact plate portion and the internal contact plate portion have the same in-plane shape with narrow portions formed at the same positions, In the terminal portion, a through hole is opened in the exterior body and the through hole is sealed with a sealing resin; The battery is configured such that the outer contact plate portion and the inner contact plate portion are stacked inside the sealing resin with their narrow portions aligned and their contact surfaces in contact with each other.

2. 10. The battery of claim 1, The outer terminal member is an exposed portion exposed to the outside; an external connection portion that connects the external contact plate portion and the exposed portion, the internal terminal member has an internal connecting portion that connects the internal contact plate portion and the power generating element, the outer contact plate portion is located on the power generating element side relative to the inner contact plate portion, an end portion of the external contact plate portion opposite to the external communication portion contacts the internal communication portion; A battery in which the end of the internal contact plate portion opposite the internal connecting portion is in contact with the external connecting portion.

3. The battery according to claim 1 or claim 2, the thickness of the narrow portion of the external contact plate portion is thinner than the thickness of the portion of the external contact plate portion other than the narrow portion; a thickness of the narrow portion of the internal contact plate portion is thinner than a thickness of the portion of the internal contact plate portion other than the narrow portion.

4. A method for manufacturing a battery including a power generating element and an exterior body that houses the power generating element, wherein a terminal portion for connecting the power generating element to an external device is provided in a part of the exterior body, the method comprising: The exterior body has a through hole formed at a location that will become the terminal portion, an external terminal member exposed to the outside at the terminal portion; an internal terminal member connected to the power generating element and made of a different metal from the external terminal member; the external terminal member has an external contact plate portion on one side which is a contact surface with the internal terminal member, the internal terminal member has an internal contact plate portion on one side which is a contact surface with the external terminal member, the external contact plate portion and the internal contact plate portion have the same in-plane shape with narrow portions formed at the same positions, The external terminal member and the internal terminal member are overlapped with each other in a state in which the narrow portions of the external contact plate portion and the internal contact plate portion are aligned and the contact surfaces thereof are pressed against each other, A method for manufacturing a battery, comprising forming a sealing resin that closes the through-hole and encases the external contact plate portion and the internal contact plate portion.

Images