JP2012252811A - Power supply device, vehicle with power supply device, and bus bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability of connection while absorbing displacement of a bus bar and battery cell.SOLUTION: A power supply device comprises a plurality of square battery cells 1 having rod-like electrode terminals 3, a metallic bus bar 2, through which the electrode terminals 3 of the square battery cells 1 are inserted, and that has a plurality of opened connection holes 4 electrically connected in a state where the square battery cells 1 are laminated on one another. In the bus bar 2, an inside diameter of the connection hole 4 is made smaller than an outside diameter of the electrode terminal 3, and the connection hole 4 is notched into a radial shape to provide a plurality of bent pieces 5. A flange 7 locking tips of the bent pieces 5 is provided on an outer periphery at the tip of the electrode terminal 3. While the electrode terminal 3 is inserted in the connection hole 4 of the bus bar 2, the bent piece 5 is deformed, and the tip of the deformed bent piece 5 is brought into contact with the flange 7 under a locked condition, so as to weld a contact part 8.

Description

  The present invention relates to a power supply device in which a plurality of battery cells are connected by a bus bar, a vehicle including the power supply device, and a bus bar, and more particularly, a power source for a motor that drives an electric vehicle such as a hybrid vehicle, a fuel cell vehicle, an electric vehicle, and an electric motorcycle. The present invention relates to a power supply device that is optimal for a large-current power supply device used for power storage for home use, household use, factory use, and the like, and a vehicle including the power supply device and a bus bar.

  The power supply device can connect a large number of battery cells in series to increase the output voltage, and can be connected in parallel to increase the charge / discharge current. Therefore, a high-current, high-output power supply device used as a power supply for a motor that runs an automobile connects a plurality of battery cells in series to increase the output voltage. Since the power supply device used for this kind of application is charged and discharged with a large current, a plurality of battery cells are connected by a bus bar made of a metal plate having a small electric resistance. Screwing or welding is performed to connect the battery cells with a bus bar. In an in-vehicle power supply device, since screwing may cause loosening due to vibration or the like, welding is preferable from the viewpoint of reliability.

  However, the position of the electrode terminal provided in the battery cell is displaced due to a manufacturing error or expansion of the outer can of the battery cell. Therefore, in order to fix a plurality of battery cells with a bus bar, a configuration that absorbs misalignment is required. Conventionally, as shown in the exploded perspective view of FIG. 25, the hole 204 opened in the bus bar 202 is formed larger than the outer diameter of the electrode terminal 203, and the outer diameter of the electrode terminal 203 is smaller than the hole 204. The electrode terminal 203 is connected to the bus bar 202 by using a donut-shaped welding ring 205 having a matching small hole 206 opened. That is, in a state where the rectangular battery cells 201 are stacked, each electrode terminal 203 is inserted into the hole 204 of the bus bar 202, and the upper part thereof is inserted into the welding ring 205, and the outer peripheral edge of the welding ring 205 is welded to the bus bar 202. The inner peripheral edge of the small hole 206 is welded to the electrode terminal 203, and the electrode terminal 203 and the bus bar 202 are connected via the welding ring 205. As a result, the position of the welding ring 205 is adjusted on the bus bar 202 to absorb the shift in the distance between the battery cells 201.

  In this method, as shown in the cross-sectional view of FIG. 26 and the plan view of FIG. 27, the space between the welding ring 205 and the electrode terminal 203 (the region indicated by the bold line in FIG. 27) and the space between the welding ring 205 and the bus bar 202 (A region indicated by a bold line in FIG. 27) is welded by laser welding or the like. For this reason, there are two positions to be welded, which increases the number of welding processes and increases the possibility that a problem of welding is probabilistic. Further, since a separate member such as a weld ring is required, the manufacturing cost is increased.

  On the other hand, a configuration in which a cross-shaped groove 306 is cut in the bus bar 302 as shown in the perspective view of FIG. 28 has been proposed to absorb misalignment (see Patent Document 1). The bus bar 302 can be deformed at the portion of the groove 306 cut in a cross shape to absorb the positional deviation. However, even in this configuration, as shown in the cross-sectional view of FIG. 29, the welding ring 305 as a separate member is still necessary, and the cost of the welding ring 305 is high and there are many places to be welded. There is a problem that it takes time, and there is a high possibility that a welding defect will occur stochastically. In addition, as shown in FIG. 30, it is conceivable to weld the bus bar 302 directly to the electrode terminal 303 without using the welding ring 305, but in this configuration, the bus bar 302 may fall off the electrode terminal 303. In particular, in an environment subject to vibration or impact such as a power supply device for in-vehicle use, the bus bar 302 may be detached by an external force, and reliability is lowered.

JP 2010-205535 A

  The present invention has been made to solve such conventional problems. A main object of the present invention is to provide a power supply device, a vehicle including the power supply device, and a bus bar that can improve the connection reliability while allowing the displacement of the bus bar and the battery cell to be displaced.

Means for Solving the Problems and Effects of the Invention

In order to achieve the above object, according to the power supply device of the first aspect of the present invention, a plurality of prismatic battery cells 1 having rod-shaped electrode terminals 3, 33, 53, 73 and the prismatic battery cells. In a state where one is laminated, a metal made by opening a plurality of connection holes 4, 34, 44, 54, 64 through which the electrode terminals 3, 33, 53, 73 of the rectangular battery cell 1 are electrically connected Bus bars 2, 32, 42, 52, 62, 72, 82, 92, and the bus bars 2, 32, 42, 52, 62, 72, 82, 92 are connected to the connection holes 4, 34, 44. , 54, 64 are made smaller than the outer shape of the electrode terminals 3, 33, 53, 73, and the connection holes 4, 34, 44, 54, 64 are notched radially to form a plurality of bent pieces 5. , 35, 45, 55, 65, and the electrode terminal 3, 3, 53, 73 are provided with a flange 7 for locking the tip of the bent pieces 5, 35, 45, 55, 65 on the outer periphery of the tip, and the bus bars 2, 32, 42, 52, 62 The bent pieces 5, 35, 45, 55, 65 are deformed with the electrode terminals 3, 33, 53, 73 inserted in the connection holes 4, 34, 44, 54, 64 of the The tips of the bent pieces 5, 35, 45, 55, 65 that have been deformed are brought into contact with the flange 7 in a locked state, and the contact portion 8 is welded.
Thereby, an electrode terminal and a bus-bar can be fixed, absorbing a position shift, without using another member like a welding ring. In the state where the electrode terminal is inserted into the connection hole, the plurality of bent pieces provided by cutting out the connection holes radially are deformed, and the tips of the deformed bent pieces are brought into contact with the flange in a locked state. This is because the contact portion is welded. In addition, by connecting the front end of the bent piece of the bus bar to the flange provided on the electrode terminal and locking it, it is possible to prevent the bus bar from falling off and to maintain the connected state reliably.

  Moreover, according to the power supply device which concerns on a 2nd side surface, the thickness (t) of the front-end | tip of the said bending pieces 5, 35, 45, 55, 65 is made larger than the protrusion amount (d) of the said flange 7. FIG. be able to. Thereby, the contact part of the front end surface of a bending piece and a flange can be exposed reliably, this part can be welded, and the malfunction of the welding by generation | occurrence | production of space can be avoided.

  Furthermore, according to the power supply device according to the third aspect, the rear end portion of the bent pieces 5, 35, 45, 55, 65 is connected to the bus bars 2, 32, 42, 52, 62, 72, 82, 92. It can be formed thinner than other portions. As a result, the bent piece can be easily deformed, and the electrode terminal can be easily inserted.

  Furthermore, according to the power supply device according to the fourth aspect, the bus bars 2 and 32 are provided with a plurality of cutout portions 6 and 36 extending radially from the connection holes 4 and 34, and the adjacent cutout portions 6 and 36. Bending pieces 5 and 35 are provided in between, and the notches 6 and 36 have an opening width (W2) on the outer side larger than the opening width (W1) on the inner peripheral side of the connection holes 4 and 34. Can do. Thereby, the width | variety of the rear-end part of a bending piece can be narrowed, a bending piece can be changed easily, and insertion of an electrode terminal becomes easy.

  Furthermore, according to the power supply device according to the fifth aspect, the bus bars 2, 32, 62, 72, 82, 92 are provided with four notches 6, 36 extending in an X shape from the connection holes, Four bent pieces 5, 35, 65 are provided in the connection holes 4, 34, 64, respectively. Thereby, a plurality of bent pieces can be provided most simply and with good appearance.

  Furthermore, according to the power supply device according to the sixth aspect, of the plurality of bent pieces 5, 35, 45, 55, 65, one set of opposed bent pieces 5, 35, 45, 55, 65 The direction of the center line m is the stacking direction of the plurality of battery cells 1. Thereby, since the deformation direction of the opposing bent piece and the stacking direction of the battery cells can be made equal, it is possible to effectively prevent the positional deviation with respect to the stacking direction of the battery.

Furthermore, according to the power supply device according to the seventh aspect, the rod-shaped electrode terminals 3 and 33 can be provided with flanges 7 and 37 that protrude outward by increasing the outer shape of the tip.
In the present specification, the flange projecting outward with the outer shape of the tip portion enlarged is not necessarily specified as a shape projecting from the entire outer periphery of the tip portion of the electrode terminal, but from the outer periphery of the tip portion of the electrode terminal. A partially protruding shape may also be used.

  Furthermore, according to the power supply device according to the eighth aspect, the rod-shaped electrode terminals 53 and 73 are provided with ring grooves 59 and 79 on the outer peripheral surface of the tip portion, and flanges are provided above the ring grooves 59 and 79. 57, 77 can be provided.

  Furthermore, according to the power supply device which concerns on a 9th side surface, the front-end | tip of the said bending piece 65 can be chamfered, and can be made to contact the lower surface of the flange 7. FIG. Thereby, the connection part of the front end surface of a bending piece and the back surface of a flange can be ensured reliably, and connectivity can be improved.

  Further, according to the power supply device according to the tenth aspect, any one of the connection holes 4 is used as the close contact hole 4X along the outer periphery of the electrode terminal 73, and the periphery of the electrode terminal 73 inserted through the close contact hole 4X. Can be welded to the opening edge of the close contact hole 4X. As a result, misalignment can be absorbed in the other connection holes with the tight connection hole as a reference. For this reason, the effect of reducing manufacturing cost is acquired by including the close contact hole of a simple structure.

  Furthermore, according to the vehicle including the power supply device according to the eleventh aspect, any one of the power supply devices described above can be mounted.

  Furthermore, according to the bus bar according to the twelfth aspect, in a state where a plurality of rectangular battery cells 1 having rod-shaped electrode terminals 3, 33, 53, 73 are stacked, the electrode terminals 3 of the rectangular battery cells 1, 33, 53, 73 is a metal bus bar formed by opening a plurality of connection holes 4, 34, 44, 54, 64 that are electrically connected to each other, the connection holes 4, 34, 44, A plurality of bent pieces 5, 35, 45, 55, 65 are provided by radially cutting out 54, 64, and the electrode terminals 3, 33, 53, 64 are provided in the connection holes 4, 34, 44, 54, 64, respectively. 73, the bent pieces 5, 35, 45, 55, 65 are deformed, and the bent pieces 5, 35, 45, 55, 65 are deformed to the electrode terminals 3, 33, 53. , 73 in a locked state, and this contact portion 8 is welded to form electrode terminals 3, 3 , And it is electrically connected to the 53 and 73.

  Furthermore, according to the bus bar according to the thirteenth side face, the center of the pair of bent pieces 5, 35, 45, 55, 65 facing each other among the plurality of bent pieces 5, 35, 45, 55, 65. The direction of the line m is the stacking direction of the plurality of battery cells 1.

It is a perspective view of the power supply device concerning one Example of this invention. It is an expansion perspective view of the power supply device shown in FIG. It is a disassembled perspective view of the power supply device shown in FIG. It is a vertical longitudinal cross-sectional view of a battery cell. It is a partially expanded sectional view which shows the connection state of the electrode terminal and bus bar of the power supply device shown in FIG. FIG. 6 is an exploded cross-sectional view showing a process of connecting the electrode terminal and the bus bar shown in FIG. 5. FIG. 4 is a plan view of the bus bar shown in FIG. 3. It is a top view which shows another example of a bus bar. FIG. 6 is a cross-sectional view illustrating a state in which the bus bar illustrated in FIG. 5 absorbs a positional deviation of battery cells. It is a top view which shows another example of a bus bar. It is a top view which shows another example of a bus bar. It is a disassembled sectional view which shows the connection process of the bus bar and electrode terminal of another example. It is sectional drawing which shows the connection state of the bus bar shown in FIG. 12, and an electrode terminal. It is a disassembled perspective view which shows the connection process of the bus bar and electrode terminal of another example. It is a perspective view which shows the connection state of the electrode terminal of another example, and a bus bar. It is an enlarged plan view which shows the connection state of the electrode terminal shown in FIG. 15, and a bus bar. It is sectional drawing which shows the connection state of the electrode terminal of another example, and a bus bar. It is sectional drawing which shows the connection state of the electrode terminal of another example, and a bus bar. It is a disassembled perspective view of the power supply device concerning the other Example of this invention. It is a perspective view which shows another example of a bus bar. It is a disassembled perspective view of the power supply device concerning the other Example of this invention. It is a block diagram which shows the example which mounts the power supply device concerning one Example of this invention in the hybrid vehicle which drive | works with an engine and a motor. It is a block diagram which shows the example which mounts the power supply device concerning one Example of this invention in the electric vehicle which drive | works only with a motor. It is a block diagram which shows the example which applies the power supply device concerning one Example of this invention to the power supply apparatus for electrical storage. It is a disassembled perspective view which shows the connection process of the bus bar and electrode terminal of the conventional power supply device. It is sectional drawing which shows the connection state of the bus bar and electrode terminal of the power supply device shown in FIG. It is a top view which shows the connection state of the bus bar and electrode terminal of the power supply device shown in FIG. It is a perspective view of the bus bar of the other conventional power supply device. It is sectional drawing which shows the connection state of the bus bar shown in FIG. 28, and an electrode terminal. It is sectional drawing which shows another example of the connection state of the bus bar and electrode terminal shown in FIG.

  Embodiments of the present invention will be described below with reference to the drawings. However, the embodiment shown below is an example of a power supply device for embodying the technical idea of the present invention, a vehicle equipped with the power supply device, a bus bar, and the present invention is a vehicle equipped with the power supply device and the power supply device. The bus bar is not specified as follows. Further, this specification does not limit the members shown in the claims to the members of the embodiments.

  The power supply apparatus of the present invention is mainly mounted on an electric vehicle such as a hybrid car or an electric vehicle, and is used as a power source for driving the vehicle by supplying electric power to a traveling motor of the vehicle. However, the power supply device of the present invention is used as a power storage device for charging a battery with power generated by solar power generation, wind power generation, or the like, or charging a battery using midnight power at night to store electricity. You can also

  In the power supply device shown in FIGS. 1 to 3, a plurality of battery cells 1 are insulated from each other and fixed in a stacked state. The battery cell 1 is a square battery cell. Further, the battery cell 1 is a rectangular battery cell made of a lithium ion battery. However, the power supply device of the present invention does not specify a battery cell as a lithium ion secondary battery. Any battery that can be charged, such as a nickel metal hydride battery, can be used for the battery cell. As shown in FIG. 4, the battery cell 1 accommodates an electrode body 10 in which positive and negative electrode plates are stacked in an outer can 11 and is filled with an electrolytic solution, and the opening is hermetically sealed with a sealing plate 12. Is. The illustrated outer can 11 is formed into a square cylinder that closes the bottom, and the upper opening is airtightly closed by the sealing plate 12.

  The outer can 11 is obtained by deep drawing a metal plate such as aluminum and has a conductive surface. The battery cells 1 to be stacked are formed into thin squares. The sealing plate 12 is made of a metal plate such as aluminum which is the same metal as the outer can 11. The sealing plate 12 has positive and negative electrode terminals 3 fixed to both ends via an insulating material 13. The positive and negative electrode terminals 3 are connected to built-in positive and negative electrode plates. The lithium ion secondary battery does not connect the outer can 11 to the electrode. However, since the outer can 11 is connected to the electrode plate via the electrolytic solution, it has an intermediate potential between the positive and negative electrode plates 10. However, a battery cell can also connect one electrode terminal to an armored can with a lead wire. The battery cell can be fixed to the sealing plate without insulating the electrode terminal connected to the outer can.

  In the power supply device, a plurality of battery cells 1 are stacked to form a battery block 9. The battery cell 1 forms a battery block 9 by laminating a surface on which the electrode terminal 3 is provided, in the drawing, a sealing plate 12 so as to be in the same plane. In the power supply device of FIGS. 1 to 3, the electrode terminal 3 is disposed on the upper surface of the battery block 9. The power supply device is laminated in a state where the positive and negative electrode terminals 3 at both ends of the sealing plate 12 are reversed from side to side. In this power supply device, as shown in the figure, the battery terminals 1 are connected in series by connecting the electrode terminals 3 adjacent on both sides of the battery block 9 with the bus bar 2. The bus bar 2 has both ends connected to the positive and negative electrode terminals 3 to connect the battery cells 1 in series. In the power supply apparatus shown in the figure, the battery cells 1 are connected in series to increase the output voltage. However, the power supply apparatus of the present invention connects the battery cells in series and in parallel to increase the output voltage and the output current. You can also

  The electrode terminal 3 is rod-shaped, and is fixed to the sealing plate 12 via an insulating material 13 as shown in FIGS. 3 and 4, and the flange portion on which the bus bar 2 is placed is provided at the lower portion with the insulating material 13. Yes. Furthermore, the rod-shaped electrode terminal 3 has a columnar shape at a portion protruding from the collar portion and inserted through the bus bar 2. Although the electrode terminal 3 shown in the figure has a cylindrical shape, the electrode terminal does not necessarily have a cylindrical shape, and may have a polygonal column shape or an elliptical column shape.

  The power supply apparatus of FIG. 1 and FIG. 2 connects adjacent battery cells 1 in series via a bus bar 2 connected to an electrode terminal 3. The bus bar 2 is a metal plate, and is provided with a plurality of connection holes 4 into which the electrode terminals 3 are inserted in order to electrically connect the electrode terminals 3 of the battery cells 1 facing each other. Since the power supply apparatus shown in the figure directly connects the battery cells 1 adjacent to each other, the bus bar 2 in the figure has connection holes 4 opened at both ends so that two electrode terminals 3 facing each other can be connected. Yes. The bus bar 2 is electrically connected by welding the opening edge of the connection hole 4 to the electrode terminal 3 in a state where the electrode terminal 3 is inserted into the connection hole 4. Therefore, the bus bar 2 is made of a metal plate that can be welded to the electrode terminal 3.

  Furthermore, the power supply device shown in the figure has a unique connection between the bus bar 2 and the electrode terminal 3 in order to connect to the electrode terminal 3 so as to absorb the misalignment between the bus bar 2 and the battery cell 1 and not fall out of the bus bar 2. It has a structure. 2 and 5 brings the bus bar 2 and the electrode terminal 3 into contact with each other in a locked state, and in this state, the contact portion 8 between the bus bar 2 and the electrode terminal 3 is welded to be electrically connected to each other. . In order to bring the bus bar 2 into contact with the electrode terminal 3 in a locked state, the bus bar 2 has an inner shape of the connection hole 4 smaller than the outer shape of the electrode terminal 3, as shown in FIGS. A plurality of bent pieces 5 are provided by cutting out 4 radially. Further, the battery cell 1 is provided with a flange 7 for locking the tip of the bent piece 5 on the outer periphery of the tip of the rod-shaped electrode terminal 3. In this power supply device, in a state where the electrode terminal 3 is inserted into the connection hole 4 of the bus bar 2, the bent piece 5 is deformed in the insertion direction of the electrode terminal 3, and the tip of the deformed bent piece 5 is connected to the flange 7. The contact portion 8 is welded in contact with the contact portion 8.

  The bus bar 2 of FIGS. 3 and 7 is provided with a plurality of cutout portions 6 extending radially from the connection hole 4 in order to provide a plurality of bent pieces 5 in the connection hole 4. A piece 5 is provided. The bus bar 2 shown in the figure is provided with four notches 6 extending in an X shape from the connection hole 4, and four bent pieces 5 are provided in the connection hole 4. However, the bus bar does not specify the number of bent pieces provided in the connection holes as four. The bus bar may be provided with five or more bent pieces in the connection hole.

  Since the bus bar 2 has an inner shape of the connection hole 4 smaller than the outer shape of the electrode terminal 3, when the electrode terminal 3 is inserted into the connection hole 4, as shown in FIG. 5 and FIG. The piece 5 is deformed in the insertion direction of the electrode terminal 3 to expand the connection hole 4 to the outer shape of the electrode terminal 3. Precisely, since the electrode terminal 3 is provided with the flange 7 at the tip, the connection hole 4 is expanded to the outer shape of the flange 7. The bus bar 2 in which the bent piece 5 is deformed allows the flange 7 of the electrode terminal 3 to pass through the expanded connection hole 4, and the tip of the bent piece 5 is brought into contact with the tip edge of the flange 7 in a locked state. . Therefore, the bus bar 2 is a metal plate that can be deformed by being pressed by the electrode terminal 3 while the electrode terminal 3 is inserted into the connection hole 4. For example, the metal plate has a thickness of 1 to 3 mm, preferably 1.5 to 2 mm. Further, the length (A) of the bent piece 5 is set such that the tip is locked to the flange 7 in a state where the electrode terminal 3 is inserted into the connection hole 4 and the bent piece 5 is deformed. That is, the length (A) of the bent piece 5 is made substantially equal to the distance from the bent portion 5B of the bent piece 5 to the leading edge of the flange 7. The position of the flange 7 of the electrode terminal 3 with respect to the bus bar 2 is specified by the height (H) of the electrode terminal 3 and the protrusion amount (d) of the flange 7. Accordingly, the bus bar 2 is adjusted so that the length (A) of the bent piece 5 becomes an optimum length in consideration of the height (H) of the electrode terminal 3 and the protrusion amount (d) of the flange 7. .

  The length (A) of the bent piece 5 is specified by the inner diameter (R) of the connection hole 4, the length (S) of the cutout portion 6, and the shape of the bent portion 5B. In the bus bar 2 shown in FIGS. 5 to 7, the rear end portion of the bent piece 5 is formed thinner than the other portions of the bus bar 2 to form a bent portion 5B. The bus bar 2 shown in the figure is a rear end portion of the plurality of bent pieces 5 and a locus k connecting the outer front end edges 6a of the plurality of cutout portions 6, that is, the deepest portion of the cut (indicated by a one-dot chain line in FIG. 7). Is formed thinner than the other portions of the bus bar 2 to provide a thin portion 22. In the bus bar 2 shown in the figure, a locus k connecting the outer front end edges 6a of the plurality of notches 6 is circular, and an arc-shaped groove 21 along the locus k is provided to form a thin portion 22. As described above, the structure in which the rear end portion of the bent piece 5 is the thin portion 22 allows the bent piece 5 to be smoothly bent in the thin portion 22 in a state where the electrode terminal 3 is inserted into the connection hole 4. Since it can be deformed, the electrode terminal 3 can be easily inserted. The bus bar 2 shown in FIG. 5 is provided with a thin portion 22 by providing a groove 21 having a circular cross-sectional shape on the lower surface side. However, the bus bar can be provided with a groove on the upper surface side to form a thin part, or can be provided with a groove on both sides to provide a thin part. However, the bus bar does not necessarily need to be provided with a thin portion at the rear end. This is because the bent piece can be easily deformed by adjusting the shape of the bent piece and the thickness of the bus bar.

  Further, the bus bar 2 shown in FIG. 7 has a circular connection hole 4 and a circular path k connecting the outer end edges 6a of the plurality of notches 6 so that the cylindrical electrode terminals 3 can be supported in a balanced manner. The arcuate thin portion 22 along the locus k is provided as the bent portion 5B. However, in the bus bar, the inner shape of the connection hole does not necessarily have a circular shape, and the trajectory connecting the outer tip edges of the plurality of notches need not have a circular shape. The bus bar may have a polygonal shape of the connection hole or the bent portion, or a substantially polygonal shape having a plurality of curved lines on each side. For example, in the bus bar 32 shown in FIG. 8, the inner shape of the front end surface 35 </ b> A of each bent piece 35 constituting the inner peripheral surface of the connection hole 34 is an arc shape along the outer shape of the flange 7. The bent piece 35 having this shape is formed in such a manner that the electrode terminal 3 is inserted into the connection hole 34 to deform each bent piece 35, and the front end surface 35 </ b> A of each bent piece 35 is connected to the front end of the flange 7 of the electrode terminal 3. Since contact can be made along the edge, the contact portion between the front end surface 35A of the bent piece 35 and the front end edge of the flange 7 can be widened and ideally welded. Further, the bus bar 32 shown in FIG. 8 has a substantially square shape of a locus k connecting the outer end edges 36a of the plurality of notches 36. Since the bus bar 32 is provided with the thin portion 22 to be the bent portion 35B in a straight line at the rear end portion of each bent piece 35, the bent piece 35 can be easily bent. For this reason, the bent piece 35 can be easily deformed in a state in which the electrode terminal 3 is inserted into the connection hole 34, and the electrode terminal 3 can be easily inserted.

  Further, the notches 6 and 36 of the bus bars 2 and 32 shown in FIGS. 7 and 8 have an opening width (W2) on the outer side larger than the opening width (W1) on the inner peripheral side of the connection holes 4 and 34. . The bus bars 2 and 32 are formed by narrowing the width of the rear end portions of the bent pieces 5 and 35, in other words, shortening the total length (B) of the bent portions 5B and 35B and deforming the bent pieces 5 and 35. Easy to do. For this reason, the bent pieces 5 and 35 can be easily deformed in a state where the electrode terminal 3 is inserted into the connection holes 4 and 34, and the electrode terminal 3 can be easily inserted.

  As described above, the bent piece can be easily deformed by making the shape of the bent portion linear and shortening the total length (B) of the bent portion. Here, the bus bar can increase the number of bent pieces provided in the connection holes, and can shorten the total length (B) of the bent portions of the bent pieces. Therefore, each bent piece can be easily deformed by increasing the number of divisions of the connection holes and providing more bent pieces. In this way, the bus bar that is provided with a large number of bent pieces and easily deforms each bent piece can be inserted while deforming each bent piece with a high degree of freedom corresponding to the electrode terminal inserted into the connection hole.

  2, 5, and 6, the front end surface 5 </ b> A of the bent piece 5 and the front end of the flange 7 are in a state where the front end of the bent piece 5 is locked to the flange 7 of the electrode terminal 3. In order to reliably expose the contact portion 8 with the edge, as shown in FIG. 5, the thickness (t) of the tip of the bent piece 5 is made larger than the protruding amount (d) of the flange 7. . In this structure, when the bent piece 5 and the flange 7 are locked, the leading edge of the flange 7 does not protrude outward from the leading end surface 5A of the bent piece 5. The contact portion 8 can be reliably exposed, and the contact portion 8 can be reliably welded. However, the power supply device can make the protrusion amount (d) of the flange larger than the thickness (t) of the tip of the bent piece. In this structure, the front end of the bent piece can be firmly locked by the flange projecting greatly.

The above power supply device connects the bus bar 2 to the electrode terminal 3 of the battery cell 1 as follows.
(1) As shown in FIG. 6, the electrode terminals 3 of the battery cells 1 adjacent to each other are inserted into the connection holes 4 provided at both ends of the bus bar 2.
(2) Since the bus bar 2 has the inner shape of the connection hole 4 smaller than the outer shape of the electrode terminal 3, when the electrode terminal 3 is inserted into the connection hole 4, as shown by the chain line in FIG. The bent piece 5 is deformed in the insertion direction of the electrode terminal 3, and the connection hole 4 is expanded to the outer shape of the flange 7 of the electrode terminal 3.
(3) The flange 7 of the electrode terminal 3 is passed through the expanded connection hole 4, and the front end surface 5A of the bent piece 5 is brought into contact with the front end edge of the flange 7 in a locked state as shown in FIG. .
(4) As shown by the arrow in the partially enlarged view of FIG. 5, the bent piece 5 is irradiated with a laser beam along the contact portion 8 between the front end surface 5 </ b> A of the bent piece 5 and the front end edge of the flange 7. The tip of is welded to the flange 7 of the electrode terminal 3 by laser welding.
However, the bus bar can be welded to the electrode terminal by irradiating an energy beam such as an electron beam instead of the laser beam. Further, since the electrode terminal and the bus bar are in contact with each other, the bus bar can be welded to the electrode terminal by passing a welding current between the electrode terminal and the bus bar.

  As described above, in the structure in which the front end surfaces 5A of the plurality of bent pieces 5 are brought into contact with the flange 7 of the electrode terminal 3 in a locked state and welded, a force acts from the outside in a direction in which the bus bar 2 is detached from the electrode terminal 3. Even so, the bus bar 2 can be reliably prevented from falling off. That is, the electrode terminal 3 and the bus bar 2 are physically connected by locking the front end surface 5A of the bent piece 5 of the bus bar 2 to the flange 7 provided at the front end portion of the electrode terminal 3. In addition, the flange 7 of the electrode terminal 3 and the tip of the bent piece 5 are welded in this state. Therefore, even if an external force acting on the power supply device acts in a direction to remove the bus bar 2 from the electrode terminal 3, the front end surface 5A of the bent piece 5 is supported by the flange 7, so that the bus bar 2, the electrode terminal 3, Thus, it is possible to reliably prevent a large load from being applied to the welded portion and to effectively prevent the welded portion from being destroyed. Therefore, the bus bar 2 is stably maintained in a connected state for a long period.

  Further, the bus bar 2 shown in FIG. 7 is folded so that the direction of the center line m of the pair of folding pieces 5 facing each other among the plurality of folding pieces 5 is the stacking direction of the plurality of battery cells 1. A curved piece 5 is provided. The bus bar 2 is provided so as to extend in the stacking direction of the battery cells 1 so as to connect the electrode terminals 3 of the battery cells 1 adjacent to each other. The direction of the center line m of the curved piece 5 is provided so as to be the longitudinal direction of the bus bar 2. In other words, the plurality of cutout portions 6 in which the connection holes 4 are cut out radially are provided so as to intersect the longitudinal direction of the bus bar 2. The above-described bus bar 2 is connected to the electrode terminals 3 of the plurality of battery cells 1 stacked on each other, and is bent by the bent pieces 5 provided in the stacking direction of the battery cells 1 in each connection hole 4. Misalignment in the stacking direction is absorbed.

  FIG. 9 shows a state where the bus bar 2 absorbs the positional deviation in the stacking direction of the battery cells 1. The battery cell 1 may have an error in thickness, and the thickness in the stacking direction may slightly change due to a change in the internal pressure of the battery cell 1 in a charged / discharged state. In such a case, the distance between the electrode terminals 3 of the battery cells 1 stacked on each other varies. Here, FIG. 5 shows a connection state between the battery cell 1 and the bus bar 2 in a state where the distance (L1) between the terminals of the adjacent battery cells 1 and the center distance (L2) of the connection hole 4 of the bus bar 2 are equal. FIG. 9 shows a connection state between the battery cell 1 and the bus bar 2 in a state where the distance (L1) between the terminals of the adjacent battery cells 1 is larger than the center distance (L2) of the connection hole 4 of the bus bar 4. Yes. As shown in FIG. 5, when the distance (L1) between the terminals of adjacent battery cells 1 and the distance (L2) between the centers of the connection holes 4 of the bus bar 2 are equal, the stacking direction of the battery cells 1 in each connection hole 4 The pair of bent pieces 5 provided on the bent portion 5 are bent in substantially the same posture, so that the bent angle (α1) of the bent piece 5 located on the inner side in the longitudinal direction of the bus bar 2 and the outer side in the longitudinal direction are positioned. The bending angle (α2) of the bent pieces 5 is equal. On the other hand, as shown in FIG. 9, in the state where the distance (L1) between the terminals of the adjacent battery cells 1 is larger than the distance (L2) between the centers of the connection holes 4 of the bus bar 2, The pair of bent pieces 5 provided in the stacking direction of the battery cells 1 are bent larger than the bent pieces 5 positioned on the inner side in the longitudinal direction. The That is, the bending angle (α2) of the bending piece 5 located on the outer side in the longitudinal direction is larger than the bending angle (α1) of the bending piece 5 located on the inner side in the longitudinal direction. It is connected to the outside of the connection hole 4 while being displaced, and the displacement of the battery cell 1 in the stacking direction is absorbed. Furthermore, although not shown, in a state where the distance (L1) between the terminals of adjacent battery cells is smaller than the distance (L2) between the centers of the connection holes of the bus bar, a pair of bendings provided in the battery cell stacking direction. The piece is in a state opposite to the above, that is, the bending angle (α2) of the bending piece located outside in the longitudinal direction is larger than the bending angle (α1) of the folding piece located inside in the longitudinal direction. It is bent in a small posture to absorb the positional deviation in the stacking direction of the battery cells. Therefore, the above bus bar is stably held in a connected state while absorbing the displacement of the electrode terminals with respect to the stacking direction of the battery cells.

  Furthermore, as shown in FIG. 5, the structure in which the electrode terminals 3 of the adjacent battery cells 1 are connected to the bus bar 2 via the deformed bent piece 5 is such that the power supply device receives various forces from the outside. Even in a vibrating state, the force acting in the stacking direction of the battery cell 1 can be absorbed and attenuated by the deformed bent piece 5, so that the load on the connection portion between the bus bar 2 and the electrode terminal 3 can be reduced. There is also.

  Furthermore, the bus bar 2 shown in FIG. 7 is arranged such that the direction of the center line m of the other pair of bent pieces 5 facing each other is the lateral direction of the battery cell 1, that is, the short direction of the bus bar 2. The bending piece 5 is provided so that it may become. Therefore, the bus bar 2 absorbs the lateral displacement of the battery cell 1 by the bent piece 5 provided in the lateral width direction of the battery cell 1 in each connection hole 4 in a state where the electrode terminals 3 of the adjacent battery cells 1 are connected. To do. Even in this state, the pair of bent pieces 5 provided in the lateral width direction of the battery cell 1 are positioned on the outer side in the lateral direction on the same principle as absorbing the positional deviation in the stacking direction of the battery cell 1 described above. The bent state of the bent piece 5 and the bent piece 5 located on the inner side in the short side direction is changed, and the lateral shift between the adjacent battery cells 1 is absorbed.

  As described above, the bus bar 2 provided with the bent pieces 5 facing the stacking direction of the battery cells 1 and the lateral displacement direction of the battery cells 1 absorbs misalignment in these directions and is adjacent to the electrode terminals of the battery cells 1. 3 can be stably maintained in a connected state. However, the bus bar is not necessarily provided with the bent pieces that face each other in the stacking direction of the battery cells and the lateral displacement direction of the battery cells. The bus bar 42 shown in FIG. 10 is provided with six bent pieces 45 by notches 46 extending radially from the connection holes 44 in six directions. The bus bar 42 shown in this figure is configured such that the direction of the center line m of the pair of opposed bent pieces 45 is the stacking direction of the battery cells 1. The bus bar 42 can absorb the deviation of the electrode terminal 3 with respect to the stacking direction of the battery cells 1 by deforming the bent pieces 45 facing the stacking direction of the battery cells 1. Further, the lateral displacement between the adjacent battery cells 1 is absorbed by the other two sets of opposed bent pieces 45. In particular, these bent pieces 45 effectively absorb the misalignment while sharing the misalignment in the oblique direction.

  Further, the bus bars 2, 32, and 42 in FIGS. 6, 7, and 10 are provided with a plurality of notches 6, 36, and 46 at equal intervals, and the bent pieces 5, 35, and 45 have the same size. And shape. As described above, the bus bars 2, 32, and 42 having the same size and shape as the plurality of bent pieces 5, 35, and 45 are inserted into the electrode terminal 3, and the bent pieces 5, 35, and 45 are balanced. It can be bent and locked to the electrode terminal 3. However, the bus bar is not necessarily required to have a plurality of bent pieces having the same size and shape, and can be changed depending on the relative position to the electrode terminal. The bus bar 52 shown in FIG. 11 is provided with eight notches 56 in the connection holes 54 and eight bent pieces 55. The bus bar 52 shown in the figure has a pair of bent pieces 55 extending in the longitudinal direction and a pair of bent pieces 55 extending in the short direction, which is wider than the four bent pieces 55 ′ positioned therebetween. Is wide. The bus bar 2 of this shape absorbs the positional deviation in the stacking direction of the battery cells 1 with a pair of bent pieces 55 extending in the longitudinal direction, and adjacent battery cells 1 with a pair of bent pieces 55 extending in the short direction. Absorbs lateral shift. Further, the four bent pieces 55 ′ located between the bent pieces 55 extending in the longitudinal direction and the short side direction absorb the positional deviation and the lateral deviation in the stacking direction, and the electrode terminals 3 and the bus bars 2. Wide contact area to achieve low resistance connection.

  Further, as shown in FIGS. 12 and 13, the bus bar can be chamfered at the front end of the bent piece 65, and the chamfered front end surface 65 </ b> A can be brought into contact with the lower surface of the flange 7. The bus bar 62 shown in FIG. 12 has a shape in which the distal end surface 65A of the bent piece 65 is inclined so that the opening area of the connection hole 64 gradually increases toward the insertion direction of the electrode terminal 3, that is, the transverse of the distal end surface 65A. The surface is chamfered into a tapered surface. As shown in FIG. 13, the bent piece 65 chamfering the tip surface 65 </ b> A in this direction contacts the flange 7 of the electrode terminal 3, and the chamfered tip surface 65 </ b> A contacts the lower surface of the flange 7. It can arrange | position in the state made to do and can ensure the connection part of 65 A of front-end | tip surfaces of the bending piece 65, and the back surface of the flange 7, and can improve connectivity. In the illustrated bent piece 65, the front end surface 65A is cut into a straight line to make the chamfered shape a tapered shape, but the front end surface of the bent piece can also be chamfered into a curved surface.

  Furthermore, as shown in FIG. 14, the bus bar 2 can be bent in advance by a plurality of bent pieces 5 provided in the connection holes 4 as a pre-process for inserting the electrode terminals 3. The bus bar 2 has a plurality of bent pieces 5 bent in advance in the insertion direction of the electrode terminals 3. Here, the plurality of bent pieces 5 are bent so that the inner shape of the connection hole 4 formed by the tip surface 5 </ b> A does not become larger than the outer shape of the flange 7 provided at the tip portion of the electrode terminal 3. This is because the front end surface 5A of the bent piece 5 is brought into contact with the front end edge of the flange 7 in a locked state. As described above, the bus bar 2 in which the plurality of bent pieces 5 are bent in advance has the connection hole 4 expanded to some extent, and therefore in the step of inserting the electrode terminal 3 into the connection hole 4, In other words, the flange 7 can be passed through the connection hole 4 by slightly expanding the bent piece 5 while reducing the deformation amount. Accordingly, the tip of the bent piece 5 can be locked to the flange 7 by inserting the electrode terminal 3 through the connection hole 4 easily and smoothly. The bus bar 2 can be bent into a predetermined shape by press-forming a plurality of bent pieces 5 with a press device or the like. Therefore, it is not always necessary to provide a thin portion at the rear end portion of the bent piece 5, and by providing no thin portion, it is possible to realize a feature that can reduce the resistance while increasing the strength of the bent portion 5B.

  Furthermore, the bus bar can be made of a metal plate that can be elastically deformed. This bus bar can be engaged with the flange of the electrode terminal by elastically deforming the bent piece while the electrode terminal is inserted into the connection hole. Since this bus bar is connected to the electrode terminal through a bent piece that is elastically deformed, the bus bar has a feature that it can elastically absorb a positional shift caused by vibration and a positional shift caused by deformation due to charge / discharge of the battery cell.

  The electrode terminal 3 of the battery cell 1 is provided with a flange 7 projecting outward in the outer periphery of the tip portion. The electrode terminal 3 shown in FIG. 2 to FIG. 6 is provided with a flange 7 that protrudes outward with the outer shape of its tip portion made larger than the outer shape of other portions of the electrode terminal 3. The electrode terminal 3 shown in the figure has a cylindrical shape, and a circular flange 7 protruding in the radial direction is provided at the upper end portion. However, the electrode terminal does not specify the shape of a cylinder. Therefore, the electrode terminal having a polygonal columnar shape can be provided with a polygonal flange so as to protrude outward from the upper end surface.

  The electrode terminal 3 shown in FIG. 3 has a cylindrical tip, and is crimped to provide a flange 7 at the tip. The flange 7 in the figure is provided over the entire outer periphery of the tip portion of the electrode terminal 3 so that its outer shape is a shape that follows the outer shape of the electrode terminal 3, that is, an outer shape that is slightly larger than the outer shape of the electrode terminal 3. Since the flange 7 can be provided at the tip of the electrode terminal 3 without directivity, the rod-shaped electrode terminal 3 can be easily processed and provided. However, the electrode terminal is not necessarily specified as a structure in which the tip portion is cylindrical and the flange is provided by caulking. The electrode terminal can also be provided with a flange projecting outwardly on the outer periphery of the tip by other processing methods.

  Further, the flange 7 of the electrode terminal 3 is not necessarily required to have a shape protruding from the entire outer periphery of the tip portion of the electrode terminal 3. The flange 7 can also have a shape partially protruding from the outer periphery of the tip portion of the electrode terminal 3. The electrode terminal 33 shown in FIGS. 15 and 16 is provided with a plurality of projecting portions 37 </ b> A projecting outward in the outer peripheral surface of the tip portion to form a flange 37. A plurality of projecting portions 37 </ b> A projecting from the distal end portion of the electrode terminal 3 are provided to face the plurality of bent pieces 5 provided in the connection holes 4 of the bus bar 2. Thereby, the front-end | tip of all the bending pieces 5 can contact the protrusion part 37A which opposes in the latching state. The electrode terminal 3 shown in the drawing is provided with a protrusion 37 </ b> A that protrudes in the stacking direction of the battery cells 1 and a protrusion 37 </ b> A that protrudes in the lateral width direction of the battery cell 1 on the outer peripheral surface of the front end portion. The flange 37 of this shape locks the front end of the bent piece 5 provided to extend in the longitudinal direction of the bus bar 2 to the protruding portion 37A that protrudes in the stacking direction of the battery cell 1, and the left and right widths of the battery cell 1. The protruding portion 37A protruding in the direction is brought into contact with the front end of the bent piece 5 extended in the short direction of the bus bar 2 in a locked state. In the flange 37 shown in the drawing, the lateral width (D) of each projecting portion 37 </ b> A is made smaller than the lateral width (C) of the distal end surface 5 </ b> A of the bent piece 5. The flange 37 that makes the lateral width (D) of the protruding portion 37A smaller than the lateral width (C) of the distal end surface 5A of the bent piece 5 is a contact portion 8 between the distal end surface 5A of the bent piece 5 and the edge of the protruding portion 37A. In addition, the laser beam can be applied to the contact portion 8 ′ between the outer peripheral surface of the electrode terminal 3 and the tip edge of the bent piece 5 for welding. However, in the flange, the lateral width of each protruding portion can be made substantially equal to or slightly larger than the lateral width of the front end surface of the bent piece. This flange can be reliably welded by lengthening the contact portion between the end face of the bent piece and the edge of the protruding portion.

  Further, the flange 7 of the electrode terminal 3 is not specified as a shape that makes the outer shape of the tip end portion larger than the other portions. The electrode terminal 3 can be provided with a groove or a recess in a portion away from the tip edge, and the top of the bent piece can be locked with the upper side of the groove or recess as a flange. The electrode terminal 53 shown in FIG. 17 has a columnar shape as a whole without having a cylindrical tip portion, and is provided with a ring-shaped groove along the tip edge on the outer peripheral surface of the tip portion. A flange 57 is provided on the upper side. That is, the electrode terminal 53 shown in the figure has a flange 57 having a shape in which the tip of the electrode terminal 53 protrudes from the bottom of the ring groove 59 by making the portion of the ring groove 59 provided at the tip narrower than the other portions. Is provided. Since this electrode terminal 53 forms a flange 57 by providing a ring groove 59 on the outer peripheral surface of the tip portion, the tip of the bent piece 5 is locked without making the outer shape of the tip portion larger than other portions. The possible flange 57 can be provided easily and firmly.

  The ring groove 59 provided in the electrode terminal 53 can have a width and a depth that can guide the front end portion of the bent piece 5 and can lock the front end surface 5A of the bent piece 5 to the front end edge of the flange 57. In this electrode terminal 53, the depth of the ring groove 59 is the protrusion amount (d) of the flange 57. As described above, the protrusion amount (d) of the flange 57 is preferably smaller than the thickness (t) of the leading edge of the bent piece 5. However, the protrusion amount (d) of the flange can be equal to or greater than the thickness (t) of the tip edge of the bent piece. Further, the flange 57 can be increased in strength by increasing the thickness (T) from the leading edge.

  Furthermore, the electrode terminal 73 shown in FIG. 18 has a lower portion of the ring groove 79 cut into a tapered shape. The electrode terminal 73 shown in the figure has a tapered surface 79A by cutting the lower part of the ring groove 79 downward so as to gradually increase its outer shape, and the outer periphery of the bent piece 5 and the electrode terminal 73 arranged here. The contact area with the surface is widened. The electrode terminal 73 having this shape can reliably engage the front end surface of the flange 77 with the front end surface 5 </ b> A of the bent piece 5 while deforming the front end of the bent piece 5 along the surface of the electrode terminal 73. In particular, by bringing the inner surface of the bent piece 5 into contact with the outer peripheral surface of the electrode terminal 73, the contact area between the bent piece 5 and the electrode terminal 73 can be increased, and a lower resistance connection can be achieved.

  Furthermore, the power supply device shown in FIG. 19 is provided with connection holes 4 at both ends of the bus bar 72, one connection hole 4 is a close contact hole 4X along the outer periphery of the electrode terminal 73, and the other connection holes 4 are radial. A plurality of bent pieces 5 are provided in the cutout. The inner shape of the close contact hole 4X is made equal to the outer shape of the electrode terminal 3 so as to contact the outer peripheral surface of the inserted electrode terminal 73 without a gap. Therefore, the electrode terminal 73 whose outer shape is not made larger than the other part is inserted into the tight connection hole 4X. In the illustrated battery cell 1, since the electrode terminal 73 has a cylindrical shape, the close contact hole 4X is a round hole. Since the electrode terminal 73 inserted into the close contact hole 4X is disposed in close contact with the inner peripheral surface of the close contact hole 4X, the contact portion between the electrode terminal 73 and the close contact hole 4X is directly welded to be electrically connected. To do. The bus bar 72 is formed by inserting the one electrode terminal 73 of the battery cell 1 while positioning in the close contact hole 4X, and deforming the bent piece 5 with the other electrode terminal 73 inserted in the other connection hole 4. The position shift between adjacent battery cells 1 is absorbed.

  Further, the bus bar is not only made of a single metal plate, but also composed of a first metal plate 82A and a second metal plate 82B made of different metal plates as shown in FIG. It can also be a clad material. In the bus bar 82, the first metal plate 82 </ b> A and the second metal plate 82 </ b> B are made of the same metal material as the electrode terminal 3 of the battery cell 1. In the lithium ion battery, since the positive and negative electrode terminals 3 are made of different metals, the first metal plate 82A and the second metal plate 82B that connect the positive and negative electrode terminals 3 are made of different metals. Since the lithium ion battery uses aluminum as the positive electrode and copper as the negative electrode, the first metal plate 82A connecting the electrode terminal 3 of the positive electrode is aluminum, and the second metal plate 82B connecting the electrode terminal 3 of the negative electrode is copper. Make with. In this bus bar 82, connection holes 4 are opened in the first metal plate 82A and the second metal plate 82B, and a plurality of bent pieces 5 are provided by notching each connection hole 4 radially.

  Further, the bus bar can connect three or more battery cells. The bus bar 93 shown in FIG. 21 is provided with four connection holes 4 and connects the electrode terminals 3 of the four battery cells 1 in a straight line. The four connection holes 4 are provided at equal intervals, and each connection hole 4 is provided with four notches 6 extending in an X shape, and four bent pieces 5 are provided in the connection hole 4. . In the power supply device shown in this figure, four battery cells 1 are connected in series and in parallel by a bus bar 92. In the illustrated battery pack, two battery cells 1 are stacked in a state where the positive and negative electrode terminals 3 are in the same direction to form a battery cell block 91, and the battery cell blocks 91 adjacent to each other have positive and negative electrodes. A plurality of battery cells 1 are stacked so that the terminals 3 are opposite to each other. The bus bar 92 is connected across two sets of adjacent battery cell blocks 91 to connect two battery cells 1 constituting each battery cell block 91 in parallel, and two adjacent sets of battery cells. The blocks 91 are connected in series, and the four battery cells 1 are connected in two parallel two rows. Further, although not shown, the bus bar is provided with 6 connection holes to connect 6 battery cells in 3 parallel 2 rows, or 8 connection holes to provide 8 battery cells 4 Can be connected in parallel

  The bus bar 92 shown in FIG. 21 has a plurality of bent pieces in which all the connection holes 4 are notched radially so that the connection to the electrode terminals 3 can be reliably performed even if the intervals between the plurality of electrode terminals 3 change due to dimensional errors. 5 is provided. However, the bus bar has a shape along the outer periphery of the electrode terminal as a reference connection hole, and has one tight connection hole without play, and the other connection holes are cut out radially to form a plurality of bent pieces. By providing, a dimensional error can also be absorbed. The bus bar including three or more connection holes is preferably connected to the battery cell while being positioned in the contact hole provided in the middle and positioned in the contact hole.

(Insulating separator)
As shown in FIGS. 1 and 5, the battery cell 1 in which the outer can 11 is made of metal insulates adjacent battery cells 1 by sandwiching an insulating spacer 15 therebetween. The insulating spacer 15 insulates the outer can 11 of the adjacent battery cell 1. Therefore, the insulating spacer 15 is manufactured by molding an insulating material such as plastic.

  The battery cell 1 shown in FIG. 1 stacked via the insulating spacer 15 is fixed at a fixed position by a fixing component 17. The fixed component 17 is a pair of end plates 18 disposed on both end faces of the stacked battery cells 1, and ends are connected to the end plates 18 to fix the stacked battery cells 1 in a compressed state. And a metal band 19.

(Cooling mechanism)
In the power supply apparatus shown in the figure, a cooling plate 14 is arranged on the bottom surface of a battery block 9 in which a plurality of battery cells 1 are insulated and laminated in an insulating separator 15, and the cooling plate 14 is cooled by a cooling mechanism 16. The plurality of battery cells 1 are cooled. The cooling mechanism 16 circulates the refrigerant through the cooling plate 14 to cool the cooling plate 14, and the cooling plate 14 is connected to the battery cell 1 in a thermally coupled state to forcibly cool the battery cell 1. The cooling mechanism 16 detects the temperature of the rectangular battery 1 and controls the temperature of the cooling plate 14. When the temperature of the battery cell 1 becomes higher than the set temperature, the cooling mechanism 16 cools the battery cell 1 through the cooling plate 14 by circulating a coolant through the cooling plate 14. When the temperature of the battery cell 1 becomes lower than the set temperature, the cooling mechanism 16 stops the circulation of the refrigerant to the cooling plate 14. However, the power supply apparatus can adopt an air cooling method in which cooling air is blown into the gaps between the battery cells to cool the plurality of battery cells without specifying the cooling method using the refrigerant. In this power supply device, ventilation grooves are provided on both surfaces of the insulating spacer to provide a cooling gap between the battery cells, and cooling air is forcibly blown into the cooling gap to cool the battery cells.

  The above power supply apparatus can be used as a vehicle-mounted power supply. As a vehicle equipped with a power supply device, an electric vehicle such as a hybrid vehicle or a plug-in hybrid vehicle that runs with both an engine and a motor, or an electric vehicle that runs only with a motor can be used, and is used as a power source for these vehicles. .

(Power supply for hybrid vehicles)
FIG. 22 shows an example in which a power supply device is mounted on a hybrid vehicle that runs with both an engine and a motor. A vehicle HV equipped with the power supply device 190 shown in this figure includes an engine 196 that travels the vehicle HV, a motor 193 for traveling, a power supply device 190 that supplies power to the motor 193, and power generation that charges a battery of the power supply device 190. Machine 194. The power supply device 190 is connected to the motor 193 and the generator 194 via the DC / AC inverter 195. The vehicle HV travels by both the motor 193 and the engine 196 while charging / discharging the battery of the power supply device 190. The motor 193 is driven to drive the vehicle when the engine efficiency is low, for example, during acceleration or low-speed driving. The motor 193 is driven by power supplied from the power supply device 190. The generator 194 is driven by the engine 196 or is driven by regenerative braking when the vehicle is braked to charge the battery of the power supply device 190.

(Power supply for electric vehicles)
FIG. 23 shows an example in which a power supply device is mounted on an electric vehicle that runs only with a motor. A vehicle EV equipped with the power supply device 190 shown in this figure includes a traveling motor 193 for running the vehicle EV, a power supply device 190 that supplies power to the motor 193, and a generator that charges a battery of the power supply device 190. 194. The power supply device 190 is connected to the motor 193 and the generator 194 via the DC / AC inverter 195. The motor 193 is driven by power supplied from the power supply device 190. The generator 194 is driven by energy when regeneratively braking the vehicle EV, and charges the battery of the power supply device 190.

(Power storage device for power storage)
Furthermore, this power supply apparatus can be used not only as a power source for a moving body but also as a stationary power storage facility. For example, as a power source for home and factory use, a power supply system that is charged with sunlight or midnight power and discharged when necessary, or a streetlight power supply that charges sunlight during the day and discharges at night, or during a power outage It can also be used as a backup power source for driving signals. Such an example is shown in FIG. The power supply device 180 shown in this figure forms a battery unit 182 by connecting a plurality of battery packs 181 in a unit shape. Each battery pack 181 has a plurality of prismatic battery cells 1 connected in series and / or in parallel. Each battery pack 181 is controlled by a power supply controller 184. The power supply device 180 drives the load LD after charging the battery unit 182 with the charging power supply CP. For this reason, the power supply device 180 has a charge mode and a discharge mode. The load LD and the charging power source CP are connected to the power supply device 180 via the discharging switch DS and the charging switch CS, respectively. ON / OFF of the discharge switch DS and the charge switch CS is switched by the power supply controller 184 of the power supply device 180. In the charging mode, the power supply controller 184 switches the charging switch CS to ON and the discharging switch DS to OFF to permit charging from the charging power supply CP to the power supply device 180. Further, when charging is completed and fully charged, or in response to a request from the load LD with a capacity of a predetermined value or more charged, the power supply controller 184 turns off the charge switch CS and turns on the discharge switch DS to discharge. The mode is switched to allow discharge from the power supply device 180 to the load LD. Further, if necessary, the charge switch CS can be turned on and the discharge switch DS can be turned on to supply power to the load LD and charge the power supply device 180 at the same time.

  The load LD driven by the power supply device 180 is connected to the power supply device 180 via the discharge switch DS. In the discharge mode of the power supply device 180, the power supply controller 184 switches the discharge switch DS to ON, connects to the load LD, and drives the load LD with the power from the power supply device 180. As the discharge switch DS, a switching element such as an FET can be used. ON / OFF of the discharge switch DS is controlled by the power supply controller 184 of the power supply device 180. The power supply controller 184 includes a communication interface for communicating with an external device. In the example of FIG. 24, the host device HT is connected according to an existing communication protocol such as UART or RS-232C. Further, if necessary, a user interface for the user to operate the power supply system can be provided.

  Each battery pack 181 includes a signal terminal and a power supply terminal. The signal terminals include a pack input / output terminal DI, a pack abnormality output terminal DA, and a pack connection terminal DO. The pack input / output terminal DI is a terminal for inputting / outputting a signal from another pack battery or the power supply controller 184, and the pack connection terminal DO is for inputting / outputting a signal to / from another pack battery which is a child pack. Terminal. The pack abnormality output terminal DA is a terminal for outputting the abnormality of the battery pack to the outside. Furthermore, the power supply terminal is a terminal for connecting the battery packs 181 in series and in parallel. The battery units 182 are connected to the output line OL via the parallel connection switch 185 and connected in parallel to each other.

  The power supply apparatus according to the present invention can be suitably used as a power supply apparatus for a plug-in hybrid electric vehicle, a hybrid electric vehicle, an electric vehicle, or the like that can switch between the EV traveling mode and the HEV traveling mode. Also, a backup power supply device that can be mounted on a rack of a computer server, a backup power supply device for a wireless base station such as a mobile phone, a power storage device for home use and a factory, a power supply for a street light, etc. Also, it can be used as appropriate for applications such as a backup power source such as a traffic light.

DESCRIPTION OF SYMBOLS 1 ... Battery cell 2 ... Bus bar 3 ... Electrode terminal 4 ... Connection hole 4X ... Close contact connection hole 5 ... Bending piece 5A ... End surface 5B ... Bending part 6 ... Notch part 6a ... Outer front edge 7 ... Flange 8 ... Contact part 8 '... contact part 9 ... battery block 10 ... electrode body 11 ... outer can 12 ... sealing plate 13 ... insulating material 14 ... cooling plate 15 ... insulating spacer 16 ... cooling mechanism 17 ... fixed component 18 ... end plate 19 ... metal band 21 ... Groove 22 ... Thin part 32 ... Bus bar 33 ... Electrode terminal 34 ... Connection hole 35 ... Bending piece 35A ... End face 35B ... Bending part 36 ... Notch 36a ... Outer end edge 37 ... Flange 37A ... Protruding part 42 ... Bus bar 44 ... Connection hole 45 ... Bending piece 46 ... Notch 52 ... Bus bar 53 ... Electrode terminal 54 ... Connection hole 55 ... Bending piece 55 '... Bending piece 56 ... Notch 57 ... Flange 59 ... Ring groove 62 ... Bus bar 64 ... connection hole 65 ... fold Piece 65A ... distal end surface 72 ... bus bar 73 ... electrode terminal 77 ... flange 79 ... ring groove 79A ... taper surface 82 ... bus bar 82A ... first metal plate 82B ... second metal plate 91 ... battery cell block 92 ... bus bar 180 ... Power supply 181 ... Battery pack 182 ... Battery unit 184 ... Power supply controller 185 ... Parallel connection switch 190 ... Power supply 193 ... Motor 194 ... Generator 195 ... DC / AC inverter 196 ... Engine 201 ... Battery cell 202 ... Bus bar 203 ... Electrode terminal 204 ... Hole 205 ... Welding ring 206 ... Small hole 302 ... Bus bar 303 ... Electrode terminal 305 ... Welding ring 306 ... Groove EV, HV ... Vehicle LD ... Load; CP ... Charging power supply; DS ... Discharge switch; CS ... Charge switch OL ... Output line: HT ... Host device DI ... Pack input / output terminal; DA ... Pack abnormal output terminal: DO ... Pack connecting terminal k ... Track m ... Center line

Claims (13)

A plurality of prismatic battery cells having rod-shaped electrode terminals;
In a state where the prismatic battery cells are stacked, a metal bus bar having a plurality of connection holes that are electrically connected through the electrode terminals of the prismatic battery cells; and
A power supply device comprising:
The bus bar has an inner shape of the connection hole smaller than the outer shape of the electrode terminal, and is provided with a plurality of bent pieces by radially cutting the connection hole,
The electrode terminal is provided with a flange for locking the tip of the bent piece on the outer periphery of the tip,
In a state where the electrode terminal is inserted into the connection hole of the bus bar, the bent piece is deformed, and a tip of the deformed bent piece is brought into contact with the flange in a locked state. A power supply device that is welded. The power supply device according to claim 1,
The power supply device, wherein a thickness (t) of a tip of the bent piece is larger than a protruding amount (d) of the flange. The power supply device according to claim 1 or 2,
The power supply device, wherein a rear end portion of the bent piece is formed thinner than other portions of the bus bar. The power supply device according to any one of claims 1 to 3,
The bus bar is provided with a plurality of cutouts extending radially from the connection hole, and a bent piece is provided between the adjacent cutouts. The cutout has an opening width on the inner peripheral side of the connection hole ( A power supply device having a larger opening width (W2) outside W1). The power supply device according to any one of claims 1 to 4,
4. The power supply device according to claim 1, wherein the bus bar is provided with four notches extending in an X shape from the connection hole, and four bent pieces are provided in the connection hole. The power supply device according to any one of claims 1 to 5,
The power supply apparatus according to claim 1, wherein a direction of a center line of the pair of bent pieces facing each other among the plurality of bent pieces is a stacking direction of the plurality of battery cells. The power supply device according to any one of claims 1 to 6,
The power supply apparatus according to claim 1, wherein the rod-shaped electrode terminal is provided with a flange projecting outward with an enlarged outer shape of a tip portion. The power supply device according to any one of claims 1 to 6,
The rod-shaped electrode terminal is provided with a ring groove on an outer peripheral surface of a tip portion, and a flange is provided on the upper side of the ring groove. The power supply device according to any one of claims 1 to 8,
The power supply device, wherein a tip of the bent piece is chamfered and is in contact with a lower surface of the flange. The power supply device according to any one of claims 1 to 9,
Any one of the connection holes is a close contact hole along the outer periphery of the electrode terminal, and the power supply is formed by welding the periphery of the electrode terminal inserted through the close contact hole to the opening edge of the close contact hole. apparatus.   A vehicle comprising the power supply device according to any one of claims 1 to 10. In a state where a plurality of prismatic battery cells having rod-shaped electrode terminals are stacked, a metal bus bar formed by opening a plurality of connection holes for electrically connecting the electrode terminals of the prismatic battery cells. There,
A plurality of bent pieces are provided by radially cutting out the connection holes;
In a state where the electrode terminal is inserted into the connection hole, the bent piece is deformed, and the deformed bent piece comes into contact with the electrode terminal in a locked state, and the contact portion is welded to the electrode terminal. A bus bar characterized in that it is electrically connected to the bus bar. The bus bar according to claim 12,
The bus bar characterized in that the direction of the center line of the pair of bent pieces facing each other among the plurality of bent pieces is the stacking direction of the plurality of battery cells.

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