JP2012079427A - Battery module and method for forming the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module capable of easily and securely connecting electrode terminals of battery cells with each other using ultrasonic junction; and a method for forming the same.SOLUTION: In a battery module formed by connecting a positive electrode terminal 111 of one battery cell 110 with a negative electrode terminal 112 of another battery cell 110, the positive electrode terminal 111 and the negative electrode terminal 112 formed in a plate-like shape, projecting to the outside of the battery cell 110, and have a plurality of junctions 120 at which the positive electrode terminal 111 and the negative electrode terminal 112 are overlapped one another so that the overlapping order can be the same to the plate thickness direction to be connected by ultrasonic junction at a plurality of places. Slit parts 111a,112a extending from the ends of each terminal 111, 112 to the battery cell 110 side and disposed between the plurality of junctions 120 are each installed in the positive electrode terminal 111 and the negative electrode terminal 112 respectively.

Description

  The present invention relates to a battery module formed by electrically connecting a plurality of secondary batteries, and a method for forming the battery module.

  As a conventional battery module, for example, a battery module disclosed in Patent Document 1 is known. The battery module (battery pack) of Patent Document 1 includes a battery block having a secondary battery (cell) therein and a circuit block having a measurement protection circuit. The battery block and the circuit block are each a block. It is electrically connected by a connection terminal provided on the.

  Further, in the battery block, the connection terminal is connected to a tab protruding from the secondary battery. The connection structure between the connection terminal and the tab is as follows. That is, a bifurcated branch portion is formed at each end of the connection terminal and the tab. In addition, among the bifurcated branch portions, the positional relationship between one branch portion and the other branch portion in the plate thickness direction is provided with a step corresponding to a substantially plate thickness. Then, the bifurcated portion of the connection terminal is inserted toward the bifurcated portion of the tab so that the overlapping order of the branched portions is reversed with respect to the plate thickness direction in one branch portion and the other branch portion. And are joined by soldering or welding. Thereby, the joining strength between the connection terminal and the tab is improved.

Japanese Patent No. 3614158

  However, using the connection structure of the connection terminal and the tab in the battery block as in Patent Document 1, it is attempted to join the positive electrode terminal and the negative electrode terminal of adjacent battery cells to a plurality of battery cells by ultrasonic bonding. In this case, since the stacking order of the positive electrode terminal and the negative electrode terminal in the plate thickness direction is reversed on one side and the other side of the bifurcated branch portion, if the plate thickness and hardness of both terminals are different, It is necessary to change the arrangement of the vibrator (horn), the pressurizing condition, and the like on the side and the other side. Alternatively, after joining one side, it is necessary to invert the combined terminals 180 degrees and perform joining on the other side, and continuous work cannot be performed, so workability is extremely lowered.

  In addition, when ultrasonic bonding is performed by simply superimposing the positive electrode terminal and the negative electrode terminal while maintaining a plate shape, if a plurality of bonding portions are provided, vibration of the bonding portion on the other side is caused with respect to the bonding portion on one side. There is a possibility that stress is generated in the joint part on one side due to the vibration from the joint part on the other side and the joint strength is lowered.

  In view of the above problems, an object of the present invention is to provide a battery module that can be easily and surely joined, and a method for forming the same, in which electrode terminals of battery cells are joined together using ultrasonic joining. There is.

  In order to achieve the above object, the present invention employs the following technical means.

In the first aspect of the present invention, a plurality of battery cells (110) are provided, and a positive electrode terminal (111) of one battery cell (110) and a negative electrode terminal (112) of another battery cell (110) are connected. In the formed battery module,
The positive electrode terminal (111) and the negative electrode terminal (112) protrude outward from the battery cell (110), are formed in a plate shape, and are stacked so that the stacking order is the same in the thickness direction. , Having a plurality of joints (120) joined at a plurality of locations by ultrasonic joining,
Each of the positive terminal (111) and the negative terminal (112) is located between the plurality of joints (120) and extends from the end of each terminal (111, 112) toward the battery cell (110). Slit portions (111a, 112a) are provided.

  According to the present invention, the positive electrode terminal (111) and the negative electrode terminal (112) are overlapped in the plate thickness direction so that the stacking order is the same, and are bonded at a plurality of locations by ultrasonic bonding. In addition, the stacking order of the positive electrode terminal (111) and the negative electrode terminal (112) in the thickness direction is not reversed in the overlapped region as in the cited patent document, and a plurality of locations are bonded by ultrasonic bonding. In this case, it is not necessary to change the arrangement of the vibrator (horn), the pressurizing condition, and the like, and the joining can be easily performed.

  Furthermore, since each of the positive terminal (111) and the negative terminal (112) is provided with slits (111a, 112a) between the plurality of joints (120), one of the joints (120) is provided. On the other hand, since the propagation of vibration by ultrasonic bonding when forming the other bonding portion (120) can be suppressed by the slit portions (111a, 112a), excessive stress is applied to one bonding portion (120). Appropriate bonding strength can be ensured without generation.

  The invention according to claim 2 is characterized in that the end of the slit portion (111a, 112a) on the battery cell (110) side is formed in an arc shape.

  According to this invention, the positive electrode terminal (111) and the negative electrode terminal (112) are accompanied by a behavior such that the opening side of the slit portions (111a, 112a) is opened or closed by vibration due to ultrasonic bonding. Thereby, the stress accompanying opening and closing of the opening side is added to the end of the slit portion (111a, 112a) on the battery cell (110) side. However, since the end of the slit portion (111a, 112a) on the battery cell (110) side is formed in an arc shape, the stress applied by the arc shape effect can be relaxed and the amount of strain can be suppressed. Further, it is possible to prevent plastic deformation, cracking, and the like at the end of the slit portions (111a, 112a) on the battery cell (110) side.

  In the invention according to claim 3, the end of the slit portion (111a, 112a) on the battery cell (110) side is formed in a circular shape having a diameter larger than the width dimension of the slit portion (111a, 112a). It is characterized by that.

  According to the present invention, a greater stress reduction effect can be obtained with respect to the invention described in claim 2, and plastic deformation and cracks at the end of the slit portion (111a, 112a) on the battery cell (110) side can be obtained. Generation | occurrence | production etc. can be prevented more effectively.

  In the invention according to claim 4, at the end of the slit portion (111a, 112a) on the battery cell (110) side, an elongated shape extending in a direction intersecting with the extending direction of the slit portion (111a, 112a). The hole (111d) is formed.

  According to the present invention, a greater stress reduction effect can be obtained with respect to the invention described in claim 2, and plastic deformation and cracks at the end of the slit portion (111a, 112a) on the battery cell (110) side can be obtained. Generation | occurrence | production etc. can be prevented more effectively.

In the invention according to claim 5, the plate-shaped reinforcing member (130) is provided outside the positive electrode terminal (111) or the negative electrode terminal (112) in the plate thickness direction, and is formed in a three-layer structure. And
The reinforcing member (130) is characterized by being joined together with the positive terminal (111) and the negative terminal (112) by ultrasonic bonding.

  In ultrasonic bonding, if the plate thickness, hardness, etc. of the positive electrode terminal (111) or the negative electrode terminal (112) are small, the vibration during bonding causes biting into the vibrator or anvil, and vibration energy for bonding. The input value of will be limited. If the input value of vibration energy is small, sufficient bonding strength cannot be secured.

  However, according to the invention described in claim 5, since the reinforcing member (130) has a three-layer structure that is on the outer side of one of the positive electrode terminal (111) and the negative electrode terminal (112) in the plate thickness direction. During ultrasonic bonding, the reinforcing member (130) can be brought into direct contact with the vibrator or anvil, and vibration energy during ultrasonic bonding can be directly received by the reinforcing member (130). Therefore, the input value of vibration energy can be increased correspondingly, so that the bonding strength can be improved.

  The invention according to claim 6 is characterized in that, of the positive electrode terminal (111) and the negative electrode terminal (112), the terminal (111) having the lower hardness is arranged in the middle of the three-layer structure.

  According to the present invention, the lower terminal (111) of the positive terminal (111) and the negative terminal (112) is arranged in the middle of the three-layer structure. ) Does not come into direct contact with the vibrator or anvil during ultrasonic bonding, but instead the reinforcing member (130) comes into direct contact. Therefore, the deformation of the terminal (111) having the lower hardness can be suppressed, and the input value of the vibration energy can be increased correspondingly, so that the bonding strength can be improved.

  In the invention according to claim 7, of the positive electrode terminal (111) and the negative electrode terminal (112), the terminal (111) having the lower hardness is bent into a U-shape or a similar shape, and one battery cell (110 ) And other battery cells (110) are arranged so as to overlap each other.

  According to the present invention, any one of the joined positive electrode terminal (111) and negative electrode terminal (112) is bent into a U shape or a similar shape, and the battery cells (110) are arranged so as to overlap each other, thereby simply connecting in series. The battery can be made compact as a whole as compared with the battery connected in general.

  And, since the terminal (111) having the lower hardness of the positive terminal (111) and the negative terminal (112) is bent into a U shape or a similar shape, the reaction force caused by the bending can be suppressed. It is possible to avoid applying excessive stress to the mating terminal (112).

  In the invention according to claim 8, one of the positive electrode terminal (111) and the negative electrode terminal (112), the longer protruding terminal (111) is bent into a U-shape or a similar shape, thereby providing one battery. The cell (110) and the other battery cell (110) are arranged so as to overlap each other.

  According to the present invention, any one of the joined positive electrode terminal (111) and negative electrode terminal (112) is bent into a U shape or a similar shape, and the battery cells (110) are arranged so as to overlap each other, thereby simply connecting in series. The battery can be made compact as a whole as compared with the battery connected in general.

  And since the terminal (111) with the longer protruding length of the positive electrode terminal (111) and the negative electrode terminal (112) is bent into a U shape or a similar shape, the reaction force caused by the bending is suppressed. Therefore, excessive stress is not applied to the counterpart terminal (112).

  The invention according to claim 9 is characterized by comprising a detection line (140) for detecting the voltage of the battery cell (110) in conduction with the superimposed positive electrode terminal (111) and negative electrode terminal (112). It is said.

  According to this invention, it can be set as the battery module (100) which can detect the voltage of a battery cell (110) with a detection line (140).

  In the invention according to claim 10, the detection line (140) is interposed between the positive electrode terminal (111) and the negative electrode terminal (112), and together with the positive electrode terminal (111) and the negative electrode terminal (112), the ultrasonic wave is detected. It is characterized by being joined by joining.

  According to this invention, the detection wire (140) can be joined between the positive electrode terminal (111) and the negative electrode terminal (112) simultaneously with the ultrasonic bonding of the positive electrode terminal (111) and the negative electrode terminal (112). The detection line (140) can be provided without increasing the number of steps for ultrasonic bonding.

In the invention according to claim 11, a plate-shaped reinforcing member (130) is provided on the outer side in the plate thickness direction of one of the positive electrode terminal (111) and the negative electrode terminal (112) to form a three-layer structure. And
The detection line (140) is connected to the reinforcing member (130).

  According to this invention, the reinforcing member (130) can be used as a member for connecting the detection line (140), and the battery module (100) including the detection line (140) can be easily formed.

In the invention according to claim 12, the reinforcing member (130) includes a bent portion (131) formed by bending an end of the reinforcing member (130).
The detection line (140) is characterized in that it is connected in a state of being sandwiched between the bent portions (131).

  According to the present invention, the detection line (140) is connected while being sandwiched between the bent portions of the reinforcing member (130), so that a strong and reliable connection is possible.

In a thirteenth aspect of the present invention, a plate-shaped reinforcing member (130) is provided on the outer side in the plate thickness direction of one of the positive electrode terminal (111) and the negative electrode terminal (112) to form a three-layer structure. And
The detection line (140) is interposed between any layers of the three-layer structure, and is joined by ultrasonic bonding together with the positive electrode terminal (111), the negative electrode terminal (112), and the reinforcing member (130). It is said.

  According to the present invention, when the reinforcing member (130) is provided to form a three-layer structure, the detection line (at the same time as the ultrasonic bonding of the positive electrode terminal (111), the negative electrode terminal (112), and the reinforcing member (130)). 140) can be bonded between the positive electrode terminal (111) and the negative electrode terminal (112), or between the reinforcing member (130) and the adjacent terminal (111), thereby increasing the number of steps of ultrasonic bonding. And a detection line (140) can be provided.

In invention of Claim 14, it is a method for forming the battery module of any one of Claims 1-13,
A plurality of joint portions (120) are formed simultaneously by ultrasonic joining.

  According to the present invention, it is possible to improve productivity by reducing the man-hours for joining the positive electrode terminal (111) and the negative electrode terminal (112) by ultrasonic bonding.

In invention of Claim 15, It is a method for forming the battery module of any one of Claims 10-13,
The formation of the plurality of joints (120) and the connection of the detection lines (140) are performed simultaneously by ultrasonic bonding.

  According to this invention, it is possible to improve productivity by reducing the number of bonding steps of the positive electrode terminal (111), the negative electrode terminal (112), the reinforcing member (130), and the detection wire (140) by ultrasonic bonding.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows a corresponding relationship with the specific means of embodiment description mentioned later.

It is a perspective view which shows a battery module. It is a top view which shows the battery cell connected in series. It is a top view which shows the positive electrode terminal and negative electrode terminal in 1st Embodiment. It is a perspective view which shows the point of the ultrasonic joining in 1st Embodiment. It is a top view which shows the junction part in 1st Embodiment. It is a side view which shows the bending part in 1st Embodiment. It is a top view which shows the positive electrode terminal in a modification. It is a perspective view which shows the point of the ultrasonic joining in 2nd Embodiment. It is a top view which shows the junction part in 3rd Embodiment. It is a side view which shows the bending part in 3rd Embodiment. It is a top view which shows the address plate and detection line in 4th Embodiment. It is a top view which shows the junction part in 4th Embodiment. It is a top view which shows the junction part in 5th Embodiment.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration. Not only combinations of parts that clearly indicate that the combination is possible in each embodiment, but also a combination of the embodiments even if they are not clearly specified unless there is a problem with the combination. It is also possible.

(First embodiment)
The first embodiment is applied to a battery module 100 including a plurality of battery cells 110. The configuration of the battery module 100 will be described with reference to FIGS. 1 is a perspective view showing a battery module 100, FIG. 2 is a plan view showing battery cells 110 connected in series, FIG. 3 is a plan view showing a positive electrode terminal 111 and a negative electrode terminal 112, and FIG. FIG. 5 is a perspective view showing the point of sonic bonding, FIG. 5 is a plan view showing the bonding portion 120, and FIG. 6 is a side view showing the bending portion 111A.

  As shown in FIG. 1, in the battery module 100, a positive terminal 111 of one battery cell 110 and a negative terminal 112 of another battery cell 110 among a plurality (four) of battery cells 110 are electrically connected in series. For example, it is used as a battery for a motor for driving a hybrid vehicle or an electric vehicle, or a storage battery for storing electricity in a house. The battery module 100 is further formed as a high voltage setting battery pack by connecting a plurality of battery modules 100.

  The battery cell 110 is a battery formed by containing a plus side electrode part and a minus side electrode part together with an electrolyte in a container formed of metal or a laminate film, for example, as shown in FIG. The outer shape of the main body is rectangular and is formed in a plate shape (flat shape). As the battery cell 110, for example, a nickel hydrogen secondary battery, a lithium ion secondary battery, an organic radical battery, or the like is used. A positive electrode terminal 111 and a negative electrode terminal 112 are provided on the short side portions of the main body portion of the battery cell 110 facing each other so as to protrude outward in the long side direction of the main body portion. The positive electrode terminal 111 and the negative electrode terminal 112 have a rectangular shape and are formed in a plate shape. Hereinafter, a direction in which the terminals 111 and 112 protrude is referred to as a protruding direction, and a direction orthogonal to the protruding direction along the surface of each terminal 111 and 112 is referred to as a width direction.

  The positive electrode terminal 111 is made of, for example, an aluminum material, and as shown in FIG. 5, the dimension in the protruding direction from the battery cell 110 is set to a predetermined length L1 that is larger than the dimension in the width direction. Moreover, the negative electrode terminal 112 is formed, for example from the copper material, and the protrusion direction dimension from the battery cell 110 is set to predetermined length L2 smaller than the width direction dimension. The predetermined length L1 is set larger than the predetermined length L2. The width direction dimension and plate thickness of the positive electrode terminal 111 and the negative electrode terminal 112 are the same.

  As shown in FIG. 3, the positive electrode terminal 111 and the negative electrode terminal 112 are provided with slit portions 111a and 112a, respectively. The slit portions 111 a and 112 a have a predetermined slit width and are formed to extend from the tip portions of the positive electrode terminal 111 and the negative electrode terminal 112 toward the main body portion side of the battery cell 110. The slit portions 111 a and 112 a are provided at the center positions of the terminals 111 and 112 in the width direction. The ends of the slit portions 111a and 112a on the battery cell 110 side are formed in a smooth arc shape to form arc portions 111b and 112b. In the slit portions 111a and 112a, regions extending with a constant slit width have a length of an overlap margin L described later, and arc portions 111b and 112b are formed at end portions on the battery cell 110 side.

  Each battery cell 110 is arranged in series so that the positive electrode terminal 111 and the negative electrode terminal 112 are along the direction of the row (FIG. 2), and the positive electrode terminal 111 and the negative electrode terminal 112 facing each other are the plates of the terminals 111 and 112. The layers are stacked so that the stacking order is the same in the thickness direction, and bonded by ultrasonic bonding as shown in FIGS. Here, “the overlapping order is the same” means that each of the terminals 111 and 112 is formed with the slit portions 111a and 112a, and the tip side is bifurcated. In both cases, the positive terminal 111 and the negative terminal 112 have the same overlapping order.

  The ultrasonic bonding is a method in which two metal members (a positive electrode terminal 111 and a negative electrode terminal 112) overlapped by an anvil (not shown) on the receiving side and a horn (vibrator) 10 on the pressing side are stacked. It is sandwiched in the direction and pressed in the plate thickness direction by the horn 10 (load application), and by applying ultrasonic vibrations in the direction in which the plate surface of the metal member expands, solid phase bonding between the two metal members is performed. is there. A mark pressed by the horn 10 remains on the surface of the metal member joined by ultrasonic joining. In the present embodiment, for example, a plurality of fine protrusions are formed at the tip of the horn 10, and a plurality of uneven marks are formed on the surface joined by ultrasonic bonding, that is, on the surface of the joint 120. Is done.

  The ultrasonic bonding between the positive electrode terminal 111 and the negative electrode terminal 112 is performed as follows. That is, first, as shown in FIG. 5, the tip of the positive terminal 111 and the tip of the negative terminal 112 are overlapped in the thickness direction. At this time, the negative electrode terminal 112 is overlapped so as to be above the positive electrode terminal 111, and the overlap margin of the tip portions of the terminals 111 and 112 is set to L. At this time, the slit portions 111a and 112a overlap each other except for the arc portions 111b and 112b. In other words, the slit portions 111a and 112a are arranged at the center position in the width direction of the stacked terminals 111 and 112, so that a space portion communicating in the thickness direction is formed.

  Next, as shown in FIG. 4, the terminals 111 and 112 overlapped above are set in the ultrasonic bonding apparatus. At this time, the positive electrode terminal 111 is disposed on the upper side of the receiving side anvil (not shown), and the negative electrode terminal 112 located on the upper side is disposed so as to face the horn 10. Then, by lowering the horn 10 and pressurizing the superimposed terminals 111 and 112 with the horn 10, ultrasonic vibrations (zigzag arrows in FIG. 4) are applied in the width direction of the negative electrode terminal 112. Then, the joint portion 120 is formed, and both the terminals 111 and 112 are joined. Here, a plurality (two) of joint portions 120 are formed in the width direction of both terminals 111 and 112 in a region where both terminals 111 and 112 are overlapped. The plurality of joint portions 120 are formed one by one in order. At this time, the slit portions 111 a and 112 a are arranged between the plurality of joint portions 120.

  Then, among the joined terminals 111 and 112, the positive electrode terminal 111 having a long length in the protruding direction is provided with a bent portion 111A having a U-shape as shown in FIG. Further, the plurality of battery cells 110 connected in series are meandered so as to face each other in the flat plate thickness direction, and the battery cells 110 are arranged (stacked) in the plate thickness direction. Thus, the battery module 100 is formed.

  As described above, in the present embodiment, the positive electrode terminal 111 and the negative electrode terminal 112 are overlapped in the plate thickness direction so that the stacking order is the same, and are bonded at a plurality of locations by ultrasonic bonding. Therefore, the stacking order in the thickness direction of the positive electrode terminal 111 and the negative electrode terminal 112 is not reversed in the overlapped region as in the cited patent document, and when joining a plurality of locations by ultrasonic bonding. It is not necessary to change the arrangement of the horn 10 or the pressurizing condition, and the joining can be easily performed. The “arrangement of the horn 10” refers to which side of the stacked terminals 111 and 112 the horn 10 should be disposed, and the “pressurizing condition” refers to a terminal (111 on the horn 10 side). 112), and how to set the applied pressure and vibration in accordance with the plate thickness and material.

  Furthermore, since each of the positive electrode terminal 111 and the negative electrode terminal 112 is provided with slit portions 111 a and 112 a between the plurality of joint portions 120, one of the plurality of joint portions 120 with respect to one joint portion 120. Since the propagation of the vibration (the wavy arrow in FIG. 4) due to ultrasonic bonding when forming the other bonding portion 120 can be suppressed by the slit portions 111a and 112a, excessive stress is applied to the one bonding portion 120. Therefore, appropriate bonding strength can be ensured.

  Moreover, the positive electrode terminal 111 and the negative electrode terminal 112 are accompanied by a behavior such that the opening side of each slit portion 111a, 112a is opened or closed by vibration due to ultrasonic bonding. As a result, stress associated with opening / closing on the opening side is applied to the ends of the slit portions 111a, 112a on the battery cell 110 side. However, in the present embodiment, since the arc portions 111b and 112b are formed at the ends of the slit portions 111a and 112a on the battery cell 110 side, the stress applied by the arc-shaped shape effect is alleviated and the amount of strain is reduced. It is possible to suppress the occurrence of plastic deformation, cracks, and the like at the ends of the slit portions 111a and 112a on the battery cell 110 side.

  In addition, either the joined positive electrode terminal 111 or negative electrode terminal 112 is bent in a U-shape, and a plurality of battery cells 110 connected in series are meandered so that the battery cells 110 overlap in the thickness direction. By disposing the battery, the battery can be made compact as a whole as compared with those simply connected in series.

  Here, the positive electrode terminal 111 is made of an aluminum material, the negative electrode terminal 112 is made of a copper material, and the positive terminal 111 has a dimension in the protruding direction of each of the terminals 111 and 112 that is larger than that of the negative electrode terminal 112. It is formed to be long, and the positive electrode terminal 111 of the positive electrode terminal 111 and the negative electrode terminal 112 is bent in a U shape. Therefore, by bending the positive electrode terminal 111 having a lower hardness (aluminum material), a reaction force accompanying the bending can be suppressed, and an excessive stress is not applied to the negative electrode terminal 112 on the other side. Similarly, by bending the positive electrode terminal 111 having a longer dimension in the protruding direction, the reaction force accompanying the bending can be suppressed, and an excessive stress is not applied to the counterpart negative electrode terminal 112.

(Modification of the first embodiment)
Each arc part 111b, 112b formed in the edge part by the side of the battery cell 110 of each slit part 111a, 112b demonstrated in the said 1st Embodiment is not limited to this, Fig.7 (a), (b ), A circular circular portion 111c having a diameter larger than the width of the slit portion 111a (112a), or an elongated shape extending in a direction intersecting with the extending direction of each slit portion 111a (112a). The hole 111d can be formed into a shape.

  As a result, a greater stress reduction effect can be obtained compared to the first embodiment, and plastic deformation, cracking, and the like at the ends of the slits 111a and 112a on the battery cell 110 side can be more effectively performed. Can be prevented.

(Second Embodiment)
A second embodiment is shown in FIG. In the second embodiment, the horn 10 is changed to a horn 10A with respect to the first embodiment (FIGS. 1 to 7).

  The horn 10 </ b> A has a tip portion branched into a plurality (two locations) toward the negative electrode terminal 112 side. The positions of the branched tip portions correspond to the positions of the plurality of joint portions 120 when the terminals 111 and 112 are joined. In 2nd Embodiment, when joining both the terminals 111 and 112, pressurization and vibration are applied by the horn 10A, and the joint part 120 of several places is formed simultaneously.

  According to the present embodiment, the man-hours for joining the positive electrode terminal 111 and the negative electrode terminal 112 by ultrasonic bonding can be reduced, and productivity can be improved.

(Third embodiment)
A third embodiment is shown in FIGS. In the third embodiment, a contact plate 130 as a reinforcing member is added to each of the terminals 111 and 112 with respect to the first embodiment (FIGS. 1 to 7).

  The contact plate 130 is a rectangular plate member whose outer shape has the same area as the region where the terminals 111 and 112 are overlapped, and either the stacked positive electrode terminal 111 or the negative electrode terminal 112 in the plate thickness direction. Arranged outside. The contact plate 130 preferably has a hardness equal to or higher than that of the both terminals 111 and 112, and is formed of a copper material, for example, like the negative electrode terminal 112. The contact plate 130 forms a three-layer structure together with the terminals 111 and 112. Here, the contact plate 130 is disposed outside the positive electrode terminal (aluminum material) 111 having low hardness. That is, as shown in FIG. 9, the three-layer structure is formed so as to overlap a negative electrode terminal 112 made of copper, a positive electrode terminal 111 made of aluminum, and a contact plate 130 made of copper, and the positive electrode terminal 111 having low hardness. Are arranged in the middle of the three-layer structure.

  Then, both terminals 111 and 112 are joined together with the contact plate 130 by ultrasonic bonding to form a joint 120 as in the first embodiment. The joint 120 causes the both terminals 111 and 112 and the contact plate 130 to be joined. Are joined. Then, as shown in FIG. 10, a U-shaped bent portion 111A is formed on the positive electrode terminal 111, and the whole of the plurality of battery cells 110 connected in series is meandered as in the first embodiment. The battery module 100 is formed so that the battery cells 110 are arranged in the thickness direction.

  Here, in ultrasonic bonding, when the plate thickness, hardness, etc. of the positive electrode terminal 111 or the negative electrode terminal 112 are small, the horn 10 (10A) or the anvil is bitten by vibration at the time of bonding. The input value of vibration energy is limited. If the input value of vibration energy is small, sufficient bonding strength cannot be secured.

  However, in this embodiment, since the contact plate 130 has a three-layer structure that is one outer side in the plate thickness direction, the contact plate 130 and the horn 10 (10A) or anvil are brought into direct contact during ultrasonic bonding. The vibration energy at the time of ultrasonic bonding can be directly received by the contact plate 130. Therefore, the deformation due to the biting on the horn 10 (10A) or the anvil can be reduced, and the input value of the vibration energy can be increased correspondingly, so that the bonding strength can be improved.

  Specifically, of the positive electrode terminal 111 and the negative electrode terminal 112, the terminal 111 having the lower hardness is arranged in the middle of the three-layer structure. 10 (10A) or the anvil is not in direct contact, but instead, the contact plate 130 is in direct contact. Therefore, the deformation of the terminal 111 having the lower hardness due to the biting of the horn 10 (10A) or the anvil can be suppressed, and the input value of the vibration energy can be increased correspondingly, thereby improving the bonding strength. be able to.

(Fourth embodiment)
A fourth embodiment is shown in FIGS. In the fourth embodiment, a detection line 140 is added to the third embodiment (FIGS. 9 and 10).

  The detection line 140 is a conducting wire for detecting the voltage of the battery cell 110 by conducting to the positive electrode terminal 111 and the negative electrode terminal 112 joined to each other. As shown in FIG. 11, the detection line 140 is connected to the contact plate 130 in advance. Here, the longitudinal dimension of the contact plate 130 is set larger than the width dimension of each of the terminals 111 and 112. Then, a bent portion 131 that is inverted and bent by 180 degrees is formed at the end portion in the longitudinal direction of the contact plate 130, and the tip end portion of the detection line 140 is sandwiched between the bent portions 131. In ultrasonic bonding, the bending portion 131 is pressed in the plate thickness direction, and ultrasonic vibration is applied in the direction along the surface of the plate to form the bonding portion 121, and the contact plate 130 and the detection line 140 are connected. It is joined.

  In this way, the contact plate 130 to which the detection line 140 is connected is arranged outside either the positive electrode terminal 111 or the negative electrode terminal 112 as in the third embodiment, and both terminals are connected by the joint 120. 111 and 112 are joined together.

  According to the present embodiment, the battery module 100 capable of detecting the voltage of the battery cell 110 by the detection line 140 can be obtained. Here, since the detection wire 140 is connected to the contact plate 130 in a three-layer structure in which the contact plate 130 is provided on the positive electrode terminal 111 and the negative electrode terminal 112, the contact plate 130 is used for connection of the detection wire 140. The battery module 100 including the detection line 140 can be easily formed. Since the detection line 140 is connected to the contact plate 130 in advance, and the contact plate 130 to which the detection line 140 is connected can be used for ultrasonic bonding with a three-layer structure, the operation is facilitated and the productivity is improved. Can be improved.

  Further, when the detection line 140 is connected to the contact plate 130, the detection line 140 is sandwiched between the bent portions 131 provided on the contact plate 130 so that the connection of the detection line 140 can be performed firmly and securely. .

  In the fourth embodiment, the detection line 140 is sandwiched between the bent portions 131 of the contact plate 130 and temporarily fixed, and the shape of the horn 10 includes a plurality of (two locations) joint portions 120 and A plurality of (three places) branches corresponding to the position of the detection line 140 with the joint 121, a plurality of joints 120 in the positive terminal 111 and the negative terminal 112, and a joint in the cover plate 130. 121 may be formed at the same time.

  Thereby, the man-hours for joining the positive electrode terminal 111, the negative electrode terminal 112, the coating plate 130, and the detection wire 140 by ultrasonic bonding can be reduced, and productivity can be improved.

(Fifth embodiment)
A fifth embodiment is shown in FIG. In the fifth embodiment, a detection line 140 is added to the third embodiment (FIGS. 9 and 10). Similarly to the fourth embodiment (FIGS. 11 and 12), the detection line 140 is a conducting wire that is electrically connected to the positive electrode terminal 111 and the negative electrode terminal 112 that are joined to each other and detects the voltage of the battery cell 110.

  In the fifth embodiment, in the three-layer structure of the positive electrode terminal 111, the negative electrode terminal 112, and the address plate 130 of the third embodiment, the detection line 140 is any of the positive electrode terminal 111, the negative electrode terminal 112, and the address plate 130. The two are interposed between the two together with the positive electrode terminal 111, the negative electrode terminal 112, and the cover plate 130 by ultrasonic bonding. For example, as shown in FIG. 13, the detection line 140 is interposed between the positive electrode terminal 111 and the negative electrode terminal 112, and is connected to the positive electrode terminal 111 and the negative electrode by the joint 120 (the upper joint 120 in FIG. 13). It is joined between the terminal 112.

  The detection line 140 is interposed between the negative electrode terminal 112 and the address plate 130 and is bonded between the negative electrode terminal 112 and the address plate 130 by the bonding portion 120 (the upper bonding portion 120 in FIG. 13). You may be made to do.

  According to the present embodiment, when the address plate 130 is provided to form a three-layer structure, the detection wire 140 is connected to the positive terminal 111 and the negative terminal simultaneously with the ultrasonic bonding of the positive terminal 111, the negative terminal 112, and the target plate 130. 112, or between the contact plate 130 and the adjacent terminal (111), and the detection line 140 can be provided without increasing the number of steps for ultrasonic bonding.

(Other embodiments)
In the above embodiments, the slit portions 111a and 112a in the terminals 111 and 112 are set at the same position so as to overlap in the width direction of the terminals 111 and 112. However, the present invention is not limited to this, and the slit portions 111a are not limited thereto. 112a may be set so as to be positioned between the plurality of joints 120, and may be displaced with respect to the width direction of each of the terminals 111 and 112.

  In each of the above embodiments, the U-shaped bent portion 111A is formed in the positive electrode terminal 111 so that the battery cells 110 are arranged in the thickness direction. However, the bent portion 111A is not limited to the U-shape. A U-shape such as a U-shape or a V-shape may be used. Further, the bent portion 111A may be formed on the negative electrode terminal 112 side. In short, the bent portion 111A may be formed as a portion that is bent so that the front and back surfaces of either of the connected terminals 111 and 112 are inverted by 180 degrees.

  In the fifth embodiment, in the three-layer structure in which the contact plate 130 is provided for the positive electrode terminal 111 and the negative electrode terminal 112, the detection line 140 includes the positive electrode terminal 111, the negative electrode terminal 112, and the contact plate 130. However, the present invention is not limited to this, and it does not have a contact plate 130 as in the first and second embodiments (FIGS. 1 to 8). Instead, when the positive electrode terminal 111 and the negative electrode terminal 112 are joined, the detection line 140 may be interposed between the terminals 111 and 112 so as to join them.

  Thereby, simultaneously with ultrasonic bonding of the positive electrode terminal 111 and the negative electrode terminal 112, the detection line 140 can be bonded between the positive electrode terminal 111 and the negative electrode terminal 112, without increasing the number of steps of ultrasonic bonding, A detection line 140 can be provided.

DESCRIPTION OF SYMBOLS 100 Battery module 110 Battery cell 111 Positive electrode terminal 111d Elongate hole part 112 Negative electrode terminal 120 Joining part 130 Address plate (reinforcing member)
140 detection lines

Claims (15)

In a battery module comprising a plurality of battery cells (110) and formed by connecting a positive electrode terminal (111) of one battery cell (110) and a negative electrode terminal (112) of another battery cell (110),
The positive terminal (111) and the negative terminal (112) are formed in a plate shape so as to protrude outward from the battery cell (110), and are stacked so that the stacking order is the same in the thickness direction. And having a plurality of joint portions (120) joined at a plurality of locations by ultrasonic joining,
Each of the positive electrode terminal (111) and the negative electrode terminal (112) is positioned between a plurality of the joint portions (120), and is connected to the battery cell (110) from an end of each of the terminals (111, 112). A battery module characterized in that slit portions (111a, 112a) extending toward the side are provided.   The battery module according to claim 1, wherein an end of the slit portion (111a, 112a) on the battery cell (110) side is formed in an arc shape.   The end of the slit part (111a, 112a) on the battery cell (110) side is formed in a circular shape having a diameter larger than the width dimension of the slit part (111a, 112a). Item 2. The battery module according to Item 1.   An elongated hole (111d) extending in a direction intersecting the direction in which the slit (111a, 112a) extends at the end of the slit (111a, 112a) on the battery cell (110) side. The battery module according to claim 1, wherein the battery module is formed. A plate-shaped reinforcing member (130) is provided on the outer side in the plate thickness direction of one of the positive electrode terminal (111) and the negative electrode terminal (112), and is formed in a three-layer structure.
The said reinforcement member (130) was joined by the said ultrasonic joining with the said positive electrode terminal (111) and the said negative electrode terminal (112), The Claim 1 characterized by the above-mentioned. Battery module.   6. The battery module according to claim 5, wherein a terminal (111) having a lower hardness of the positive terminal (111) and the negative terminal (112) is disposed in the middle of the three-layer structure. .   Of the positive terminal (111) and the negative terminal (112), the terminal (111) having the lower hardness is bent into a U shape or a similar shape, so that the one battery cell (110) and the other battery The battery module according to any one of claims 1 to 6, wherein the cells (110) are arranged so as to overlap each other.   Of the positive electrode terminal (111) and the negative electrode terminal (112), the longer protruding terminal (111) is bent into a U shape or a similar shape, and the one battery cell (110) and the The battery module according to any one of claims 1 to 6, wherein the other battery cells (110) are arranged to overlap each other.   The detection line (140) for detecting the voltage of the battery cell (110) in conduction with the superimposed positive electrode terminal (111) and the negative electrode terminal (112). The battery module according to claim 8.   The detection line (140) is interposed between the positive terminal (111) and the negative terminal (112), and is joined together with the positive terminal (111) and the negative terminal (112) by the ultrasonic bonding. The battery module according to claim 9, wherein the battery module is a battery module. A plate-shaped reinforcing member (130) is provided on the outer side in the plate thickness direction of one of the positive electrode terminal (111) and the negative electrode terminal (112), and is formed in a three-layer structure.
The battery module according to claim 9, wherein the detection line (140) is connected to the reinforcing member (130). The reinforcing member (130) includes a bent portion (131) formed by bending an end portion of the reinforcing member (130).
The battery module according to claim 11, wherein the detection line (140) is connected while being sandwiched between the bent portions (131). A plate-shaped reinforcing member (130) is provided on the outer side in the plate thickness direction of one of the positive electrode terminal (111) and the negative electrode terminal (112), and is formed in a three-layer structure.
The detection line (140) is interposed between any layers of the three-layer structure, and together with the positive electrode terminal (111), the negative electrode terminal (112), and the reinforcing member (130), is ultrasonically bonded. The battery module according to claim 9, wherein the battery module is joined. A method for forming a battery module according to any one of claims 1 to 13, comprising:
A method for forming a battery module, wherein the plurality of joints (120) are simultaneously formed by the ultrasonic bonding. A method for forming a battery module according to any one of claims 10 to 13, comprising:
A method for forming a battery module, wherein the formation of a plurality of the joints (120) and the connection of the detection lines (140) are simultaneously performed by the ultrasonic bonding.

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