Battery and method for manufacturing the same

Abstract

To provide a terminal member capable of being arranged over an inside and an outside of an outer casing body in a battery, and being formed only by a bending processing or a twisting processing on the basis of a strip-like metal board, a battery, and a manufacturing method.SOLUTION: A terminal member of a battery according to a present disclosure technique, includes: a power collector part 26 that is connected to a power generation element in an inner part of the battery; and a terminal surface 8 that is exposed to the external part of the battery. Both of a width and a thickness of a whole of an end part on the power collector part 26 side to an end part on the terminal surface 8 side is constructed by a constant integrated strip-like conductive member. At a position in the middle between the power collector part 26 and the terminal surface 8, deformation places 22, 23, and 24 to which a bending deformation that the conductive member is bent by a bending wire to a direction crossed to their length direction or a twisting deformation that the conductive member is twisted to a twisting shaft of a direction along their length direction are provided.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The disclosed technology relates to batteries, their terminal members, and methods for manufacturing them.

Background Art

[0002] As a conventional battery terminal member, the "current collecting connection body" described in Patent Document 1 can be cited. This current collecting connection body is obtained by bending a strip-shaped metal plate. In this current collecting connection body, one side of the fold perpendicular to the longitudinal direction of the strip shape is the "terminal connection part", and the other side is the "first plate part for positioning". A part of the "first plate part for positioning" is further subjected to bending by a fold in a direction parallel to the longitudinal direction of the strip shape. As a result, the portion near the end of the "first plate part for positioning" has an L-shaped cross section.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The above-mentioned conventional technology had the following problems. Since a portion with an L-shaped cross section was formed, a part of the "first plate part for positioning" became a triangular inclined portion. This portion is a site that has expanded in area during bending, and thus is thinner than the original thickness. This is a factor contributing to an increase in electrical resistance. Also, each piece of the portion with an L-shaped cross section is narrower than the full width of the original strip shape. This means that the full width of the current collecting connection body cannot be fully utilized for current collection from the electrodes of the power generation element.

[0005] The objective of this disclosed technology is to provide a terminal member that is arranged both inside and outside the outer casing of a battery and can be formed solely by bending or twisting a strip-shaped metal plate, as well as a battery using this terminal member, along with a method for manufacturing them. [Means for solving the problem]

[0006] A terminal member for a battery in one aspect of the disclosed technology has a current collector that is connected to a power generation element inside the battery and a terminal surface exposed to the outside of the battery, and the entire length from the end on the current collector side to the end on the terminal surface side is made of a single, rectangular conductive member having a constant width and thickness, and a deformation point is provided at an intermediate position between the current collector and the terminal surface in which the conductive member is bent along a bending line intersecting its longitudinal direction, or torsionally deformed by twisting the conductive member with respect to a torsion axis in a direction along its longitudinal direction.

[0007] In another embodiment of the disclosed technology, a method for manufacturing a battery terminal member involves cutting a single, rectangular conductive member of a certain width from a conductive base plate of a certain thickness, and forming a deformed portion in the conductive member at an intermediate position between the position to be a current collector and the position to be a terminal surface by bending the conductive member along a bending line intersecting its longitudinal direction, or by torsion deformation by twisting the conductive member with respect to a torsion axis in a direction along its longitudinal direction, thereby manufacturing a battery terminal member having a current collector connected to a power generation element inside the battery and a terminal surface exposed to the outside of the battery.

[0008] The above-described battery terminal component and its manufacturing method are easy to manufacture and contribute to a reduction in the number of components, improved resistance and heat dissipation characteristics, and increased design flexibility.

[0009] A battery in one aspect of the disclosed technology comprises a power generation element, an outer casing housing the power generation element and having terminal openings, and a terminal member positioned through the terminal openings and having a current collector connected to the power generation element inside the outer casing and a terminal surface exposed outside the outer casing, wherein the terminal member is the one described above.

[0010] In another aspect of the disclosed technology, a method for manufacturing a battery comprises a power generation element, an outer casing housing the power generation element and having terminal openings formed therein, and a terminal member positioned through the terminal openings and having a current collector connected to the power generation element inside the outer casing and a terminal surface exposed outside the outer casing. In this method, the terminal member is manufactured by the manufacturing method described above.

[0011] In each of the above embodiments, it is desirable to form an external deformation area located outside the terminal opening and subjected to bending deformation, and an internal deformation area located inside the terminal opening, and to include at least a torsional deformation area within the internal deformation area. [Effects of the Invention]

[0012] According to the disclosed technology, terminal members that are arranged both inside and outside the outer casing of a battery and can be formed solely by bending or twisting a strip-shaped metal plate, as well as a battery using such terminal members, are provided along with their manufacturing methods. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view of the external appearance of the battery according to the embodiment. [Figure 2] This is a perspective view showing the shape of the terminal member according to the first embodiment. [Figure 3] Figure 2 is a perspective view showing the connection between the terminal member and the power generation element. [Figure 4] This is a cross-sectional view of the external terminal area. [Figure 5]It is a front view of the strip material before processing the terminal member of FIG. 2. [Figure 6] It is a flowchart showing the manufacturing procedure of the terminal member according to the embodiment. [Figure 7] It is a perspective view showing the shape of the terminal member according to the second embodiment. [Figure 8] It is a side view showing the connection state between the terminal member of FIG. 7 and the power generation element. [Figure 9] It is a front view of the strip material before processing the terminal member of FIG. 7. [Figure 10] It is a perspective view showing the shape of the terminal member according to the third embodiment. [Figure 11] It is a perspective view showing the shape of the terminal member according to the fourth embodiment. [Figure 12] It is a perspective view showing the shape of the terminal member according to the fifth embodiment.

Embodiments for Carrying out the Invention

[0014] This embodiment embodies the disclosed technology in the battery 1 shown in FIG. 1. The battery 1 is formed by housing a power generation element 3 in an exterior body 2. The exterior body 2 has a box body 4 and a lid body 5. Positive and negative external terminals 6 and 7 are provided on the lid body 5. When viewed from the outside of the battery 1, terminal surfaces 8 and 9 and insulating resins 10 and 11 can be seen at the locations of the external terminals 6 and 7.

[0015]

[0016] ​Among the terminal member 21, the part to the upper right of the fold line 22 in FIG. 2 is an external terminal portion 25 that is located outside the lid body 5 in the battery 1. The upper surface of the external terminal portion 25 is a portion that is externally exposed as the terminal surface 8 or the terminal surface 9 in FIG. 1. Among the terminal member 21, the part below the fold line 24 in FIG. 2 is a current collecting portion 26 that is connected to the power generation element 3 inside the battery 1. As shown in FIG. 3, the current collecting portion 26 is joined to the end face 12 of the power generation element 3. In FIG. 3, only the terminal member 21 and the power generation element 3 in the battery 1 are shown. The fold lines 22, 23, and 24 are all located midway between the current collecting portion 26 and the external terminal portion 25.

[0017] The portion between the fold line 22 and the fold line 23 of the terminal member 21 is a through portion 27 that penetrates the lid body 5 in the battery 1. The through portion 27 and the current collecting portion 26 are connected via the fold lines 23 and 24. The through portion 27 and the current collecting portion 26 are substantially parallel. While the current collecting portion 26 is connected to the power generation element 3, there is a gap between the through portion 27 and the power generation element 3. In the battery 1, the width direction of the through portion 27 is parallel to the short side of the lid body 5.

[0018] The structure of the location of the external terminal 6 in the battery 1 will be described. A cross-sectional view of the location of the external terminal 6 is shown in FIG. 4. As shown in FIG. 4, a terminal hole 15, which is a through hole, is formed in the lid body 5. One side of the external terminal portion 25 of the terminal member 21 is exposed outside the lid body 5 and becomes the terminal surface 8 shown in FIG. 1. The terminal surface 8 is a portion to which a conductive member outside the battery, such as a bus bar, is joined. The through portion 27 of the terminal member 21 passes through the terminal hole 15 and exists across the inside and outside of the lid body 5. In the example of FIG. 4, the portion of the through portion 27 closest to the fold line 22 is at the same level as the lid body 5. The fold line 22 is an example of an external deformation location provided outside the terminal hole 15 and subjected to bending deformation. The current collecting portion 26 exists below the lid body 5 in FIG. 4, that is, inside the exterior body 2. The fold lines 23 and 24 are examples of internal deformation locations provided inside the terminal hole 15.

[0019] The terminal member 21 is manufactured by bending a strip-shaped strip material 28 shown in Figure 5. The strip material 28 is rectangular in shape with length L and width W. The width W and thickness of the strip material 28 are constant at any position along the length L. Therefore, the area of ​​the cross-section of the strip material 28 perpendicular to the length direction is constant at any position along the length L.

[0020] The manufacturing procedure for the terminal member 21 is as shown in Figure 6. The coil that will serve as the base plate is made by winding a metal plate with the same thickness as the flat portion of the terminal member 21. First, strips of the above size 28 are cut from the coil by shearing (S1). If a coil with the same width as the width W is used, the strips 28 can be obtained by shearing in the width direction at intervals of length L. Of course, this is not the only option; a coil with the same width as the length L may also be used, and shearing may be performed at intervals of width W. Alternatively, the strips 28 may be cut by shearing in two directions: the width direction and the longitudinal direction.

[0021] The cut strip material 28 is subjected to a bending process (S2). The bending points correspond to the three folds 22, 23, and 24 mentioned above. In Figure 5, these positions are indicated by the bend lines 22, 23, and 24. The bend lines 22, 23, and 24 all intersect the length direction of the strip material 28. Also, all of them are located midway between the position that will become the current collection part 26 and the position that will become the external terminal part 25. "S2" in Figure 6 also includes a twisting process, which is done in consideration of the second form described later.

[0022] The edges of the processed terminal member 21 can be chamfered (S3). However, chamfering is not mandatory. Chamfering reduces the abrasive potential of the terminal member 21's edges to other parts, but it slightly reduces the cross-sectional area of ​​the terminal member 21 and increases the number of processing steps. If chamfering is not performed, the terminal member 21 is considered complete upon completion of the bending process. If chamfering is performed, the terminal member 21 is considered complete upon completion of the chamfering. Subsequently, the battery 1 is manufactured by attaching the terminal member 21 to the lid 5, joining the terminal member 21 to the power generation element 3, housing the power generation element 3 in the housing 4, and sealing the housing 4 with the lid 5.

[0023] Using the above-described terminal member 21 as a component of the battery 1 offers the following advantages. Firstly, it contributes to reducing the overall number of parts in the battery 1. This is because it is a single component that extends from its exposure to the outside of the casing 2 (external terminal portion 25) to the connection point with the power generation element 3 inside the casing (current collection portion 26). Secondly, the terminal member 21 is easy to manufacture. This is because the terminal member 21 can be manufactured simply by cutting strips of material 28 from a base plate and bending the strips of material 28.

[0024] Thirdly, it contributes to reducing the conductive resistance of battery 1. This is because the cross-sectional area of ​​the terminal member 21 is almost constant from the end on the current collection part 26 side to the end on the external terminal part 25 side. This is because, as mentioned above, the width W and thickness of the strip material 28 are constant. Furthermore, the only processing applied to the strip material 28 is bending, and no expansion in terms of area has been performed. As a result, the terminal member 21 has no thin or narrow sections, and there are no particular areas where current concentrates. Consequently, there are no places where electrical resistance increases locally. The same can be said for the heat conduction of the terminal member 21. As a result, there are no places in the terminal member 21 where heat accumulates locally and the temperature rises.

[0025] Fourth, the raw material utilization efficiency is high. Because the strip material 28 has a simple strip shape, only a small amount of the raw material is wasted. Fifth, the battery 1 is easy to design. The resistance of the terminal member 21 can be set simply by adjusting the width W and thickness of the strip material 28. Sixth, when aiming for a sharp edge, no additional process is required. This is because the aforementioned chamfering must be omitted.

[0026] A second form of the terminal member will now be described. Figure 7 shows the terminal member 29 according to the second form. The terminal member 29 is similar to the terminal member 21 of the first form in that it is manufactured from a strip-shaped strip material 28. The terminal member 29 has five folds 22, 23, 24, 30, and 31, and one twisted section 32. The folds 22, 23, and 24 are the same as those of the terminal member 21. The tip of the fold 22 is the external terminal section 25, and the section below the fold 24 is the current collection section 26, which is also the same as the terminal member 21.

[0027] The deformations in terminal member 29 that are not present in terminal member 21 are the twisted portion 32 and the folds 30 and 31. The twisted portion 32 is a deformation in the strip material 28 that has been twisted. The twisted portion 32 is located between the folds 22 and 23. The location where the twisted portion 32 is formed is located inside the outer casing 2 in battery 1. In other words, the through portion 27 in terminal member 29 is the section between the fold 22 and the twisted portion 32.

[0028] Folds 30 and 31 are located between the twisted section 32 and fold 23. Fold 30 is located very close to the twisted section 32. The bending angles of both folds 30 and 31 are approximately 90°. Folds 30 and 31 and the twisted section 32 are examples of internal deformation points located inside the terminal opening 15.

[0029] The shape of the terminal member 29, as shown in Figure 8, is for joining the current collector 26 to the side surface of the power generation element 3. When using the terminal member 29, the power generation element 3 is compressed in the thickness direction (left-right direction in Figure 8) by joining with the current collector 26 at the unpainted end portion, as shown in Figure 8. The upper and lower parts of the power generation element 3 become bulging. The folds 30 and 31 are deformation points to avoid interference with the bulging parts of the power generation element 3. The terminal member 29 in Figure 8 is viewed from the direction of arrow A in Figure 7. The width direction of the through-hole 27 of the terminal member 29 is also parallel to the short side of the cover 5. By having a twisted section 32 as an internal deformation point, a shape in which the current collector 26 and the through-hole 27 are not parallel can be realized.

[0030] The manufacturing procedure for the terminal member 29 is basically the same as that for the terminal member 21. The difference is that "S2" in Figure 6 includes twisting, and there are more bending processes. Figure 9 shows the strip material 28 for the terminal member 29. The strip material 28 in Figure 9 includes twisted sections 32. The twisted sections 32 in Figure 9 are the areas where twisting will be performed at "S2" in Figure 6. During the twisting process, the twisted sections 32 of the strip material 28 are twisted with respect to the twist axis B in the direction along the length of the strip material 28, causing torsional deformation. As a result, the twisted sections 32 with the shape shown in Figure 7 are formed. In the terminal member 29, the twist angle of the twisted sections 32 is approximately 90°.

[0031] Comparing terminal member 21 (Figure 2) and terminal member 29 (Figure 7), both have at least the outer surface of the fold 22 located outside the cover 5. This means that the external terminal portion 25 is positioned almost parallel to the plate surface of the cover 5. However, focusing on the internal configuration of the outer casing 2, terminal member 21's current collector portion 26 is joined to the end face 12 of the power generation element 3 (Figure 3), whereas terminal member 29's current collector portion 26 is joined to the side surface of the power generation element 3 (Figure 8). This difference represents the design flexibility resulting from variations in the folds and twists.

[0032] Therefore, the terminal member of this embodiment can be modified in various ways, not limited to those shown in Figure 2 (first embodiment) and Figure 7 (second embodiment). The terminal member 33 shown in Figure 10 has a longer external terminal portion 25 and a shorter through portion 27 compared to the terminal member 21. It is not essential to have a fold 22 on the outside of the cover 5. The terminal member 34 shown in Figure 11 omits the fold 22 compared to the terminal member 29. In the terminal member 34, there is no shape boundary between the external terminal portion 25 and the through portion 27. In a battery using the terminal member 34, the external terminal portion 25 is upright relative to the plate surface of the cover 5. The terminal member 35 shown in Figure 12 further omits the twisted portion 32 compared to the terminal member 34. In a battery using the terminal member 35, the external terminal portion 25 is also upright relative to the plate surface of the cover 5. The fact that such a variety of modifications are possible is also an advantage of the terminal member of this embodiment.

[0033] As described in detail above, according to this embodiment, terminal members are manufactured by bending and twisting only a single strip material 28 with a constant width and thickness. This enables the creation of terminal members that are positioned both inside and outside the outer casing 2 of a battery, are easy to manufacture, and have excellent conductivity and heat dissipation properties, as well as a battery using such terminal members, along with a manufacturing method for them.

[0034] These embodiments 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 its essence. For example, the terminal member of this embodiment may be applied to both the positive and negative electrodes of a battery, or to only one of them. If applied to only one, it may be applied to either the positive or negative electrode. The type of battery to which it is applied (e.g., lithium-ion battery, nickel-metal hydride battery) is irrelevant.

[0035] The terminal members 21 shown in the illustration all have folds 23 and 24, but this is not a mandatory shape. Depending on the relationship between the placement of the terminal members on the cover 5 and the size of the power generation element 3, it is possible to have a flat surface without folds 23 and 24. The folds may be oblique, not perpendicular to the longitudinal direction of the strip material 28. The twist angle of the twisted section is not limited to 90°. While examples of terminal members with folds but no twisted sections (Figure 2, etc.) and those with both folds and twisted sections (Figure 7, etc.) are shown, it is also possible to have a terminal member with a twisted section but no folds. In Figure 2, the terminal member 21 is joined to the end face 12 of the power generation element 3, and in Figure 7, the terminal member 29 is joined to the side surface of the power generation element 3, but the reverse is also possible. In that case, the width direction of the through-hole 27 is parallel to the long side of the cover 5. [Explanation of symbols]

[0036] 1 battery 22 folds 2 Outer casing 23 folds 3 Power generation element 24 folds 4 Box 25 External terminal section 5 Cover 26 Current collector 6 External terminals 28 Strip material 7 External terminals 29 Terminal components 8 terminals, 30 folds 9 terminal side 31 fold 15 terminal openings 32 twisted points 21 Terminal member 33 Terminal member

Claims

1. A battery comprising a power generation element, an outer casing housing the power generation element and having a terminal opening, and a terminal member positioned through the terminal opening and having a current collector connected to the power generation element inside the outer casing and a terminal surface exposed outside the outer casing, The terminal member is The entire length from the end on the current collection side to the end on the terminal surface side is made up of a single, rectangular conductive member with a constant width and thickness. An external deformation point is provided at a position outside the terminal opening, midway between the current collection section and the terminal surface, where the conductive member is bent along a bending line intersecting its longitudinal direction. An internal deformation point is provided at a position inside the terminal opening between the current collection section and the terminal surface, where the conductive member is subjected to bending deformation or torsional deformation in which it is twisted with respect to a torsion axis in the direction along its longitudinal direction. A battery in which the outer surface of the portion of the terminal member that is on the end side of the externally deformed portion is the terminal surface.

2. The battery according to claim 1, The battery includes, at least, a torsionally deformed area among the internally deformed areas.

3. A method for manufacturing a battery comprising a power generation element, an outer casing housing the power generation element and having a terminal opening, and a terminal member positioned through the terminal opening and having a current collector connected to the power generation element inside the outer casing and a terminal surface exposed outside the outer casing, wherein the manufacturing of the terminal member is: From a conductive base plate of a constant thickness, a single, rectangular conductive member of a constant width is cut out. In the conductive member, at a position outside the terminal opening between the position that will be the current collection part and the position that will be the terminal surface, the conductive member is subjected to bending deformation by bending along a bending line that intersects its longitudinal direction, thereby forming an external deformation area. This is done by forming an internal deformation point in the conductive member at a position inside the terminal opening, midway between the position that will become the current collection part and the position that will become the terminal surface, by bending deformation or torsional deformation, in which the conductive member is twisted with respect to a torsion axis in the direction along its longitudinal direction. A method for manufacturing a battery, wherein the outer surface of the portion of the terminal member that is on the end side of the externally deformed portion is the terminal surface.

4. A method for manufacturing a battery according to claim 3, A method for manufacturing a battery, wherein the internal deformation area includes at least a torsionally deformed area.

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