JP2011233491A - Battery pack and connection method between electrode terminals - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack and a connection method between electrode terminals improving productivity by reducing a man-hour of connection between terminals.SOLUTION: In the battery pack 1, a plurality of battery cells 10 having an electrode terminal 11 projected from an exterior case 12 are laminated and the electrode terminals 11 of neighboring battery cells 10 are connected each other with a bus bar 50 for electric conduction. In the bus bar 50, a first through hole 51 and a second through hole 51A having an inner diameter dimension that is equal to or less than the outer shape of the electrode terminal 11 of the battery cell 10 and penetrating in the thickness direction are formed and slits 52 extending from the respective inner peripheral edges to the exteriors of the first through hole 51 and the second through hole 51A are formed. The electrode terminals 11 are press-fitted into the first through hole 51 and the second through hole 51A respectively. The inner peripheral parts of the first through hole 51 and the second through hole 51A surely hold the electrode terminals 11 deformed by extending and press-fitted.

Description

  The present invention relates to a battery pack that is an assembly of a plurality of stacked battery cells and a method for connecting electrode terminals in the battery pack.

  Patent document 1 is a prior art which disclosed the inter-terminal connection structure which electrically connects between the terminals of the batteries which have the positive electrode terminal and negative electrode terminal which protrude from an exterior body.

  In the inter-terminal connection structure described in Patent Document 1, a bolt part (male thread part) or a nut part (female thread part) is formed on each terminal projecting outside the exterior body in each battery arranged adjacently. Yes. When the terminals of adjacent batteries are electrically connected, the terminals requiring electrical connection are respectively passed through the two through holes formed in the bus bar, and the terminals to be electrically connected are connected by the bus bar. Further, when a bolt part is formed on each terminal, a nut is tightened on the bolt part (see FIG. 2 of Patent Document 1), and when a nut part is formed, the nut part is bolted. (See FIG. 3 of Patent Document 1). As described above, in the prior art described in Patent Document 1, it is necessary to perform nut tightening or bolt tightening for each electrically connected terminal.

JP 2009-80963 A

  However, in the above-described prior art, a fastening process using bolts or nuts as many as the number of terminals that need to be connected is necessary. In the battery pack of an assembly in which a large number of battery cells are stacked, the number of man-hours is enormous. Pack productivity was impaired. There is also a problem that the number of parts increases due to the need for nuts or bolts.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a battery pack and a connection method between electrode terminals that reduce man-hours for connection between terminals and improve productivity. .

The present invention employs the following technical means to achieve the above object. That is, claim 1 is a battery cell in which a plurality of battery cells (10) having a positive electrode terminal and a negative electrode terminal (11) projecting from the outer case (12) are stacked and adjacent in the stacking direction (X). The battery pack (1) is configured to connect the terminals to be connected to each other using a bus bar (50) so as to be energized.
The bus bar has a first through hole (51A) and a second through hole (51A) each having an inner diameter dimension equal to or smaller than the outer dimension of the battery cell terminal and penetrating in the thickness direction. (51) and a slit (52) extending outward from the inner peripheral edge of each of the second through holes (51A),
The terminal to be connected is fitted in each of the first through hole (51) and the second through hole (51A), and the terminal to be connected is connected and fixed by a bus bar.

  According to this invention, when the terminal to be connected to the battery cell is fitted in each of the first through hole and the second through hole of the bus bar, each through hole is pushed and expanded by press-fitting of the electrode terminal. The outer peripheral surface of the battery cell terminal can be firmly held by the inner peripheral wall surface of the hole. The bus bar is firmly held by the electrode terminal by the action of the bus bar. Therefore, compared with the inter-terminal connection process by nut tightening or bolt tightening of the prior art described above, it is possible to significantly reduce the man-hours for inter-terminal connection and to provide a battery pack with improved productivity.

  A second aspect of the present invention is the battery pack according to the first aspect, wherein the bus bar (50) is made of an elastic body. According to the present invention, when the terminal to be connected to the battery cell is fitted in each of the first through hole and the second through hole of the bus bar, the bus bar is formed of an elastic body, so that the electrode terminal is press-fitted. The bus bar can be extended and deformed in the direction in which the through holes are arranged, that is, in the stacking direction (X). Therefore, even when variations occur in the pitch dimensions between a plurality of electrode terminals to be connected in the manufacturing process, the bus bar is deformed so as to be able to cope with these variations, so that smooth connection can be performed, and further production can be performed. Can improve the performance.

  According to a third aspect of the present invention, in the battery pack according to the first or second aspect, the bus bar (50) has an outer side from an inner peripheral edge of each of the first through hole (51) and the second through hole (51A). An extending slit (52) is formed. According to the present invention, when the terminal to be connected to the battery cell is fitted in each of the first through hole and the second through hole of the bus bar, the slits are the inner peripheral edges of the first through hole and the second through hole, respectively. Since it is formed so as to extend outward from the portion, it is easy to enlarge each through hole with the deformation of the slit. Therefore, it is possible to provide a battery pack that can further reduce the number of man-hours for connection between terminals and improve productivity.

  According to a fourth aspect of the present invention, in the battery pack according to the third aspect, the slit (52A) extends outward from the inner peripheral edge in a direction (Y) perpendicular to the stacking direction (X) of the battery cells. And According to this invention, the slits extending in the direction perpendicular to the stacking direction are formed in the inner peripheral edge of each of the first through hole and the second through hole, so that the electrode terminal to be connected can be connected by the bus bar. When connecting, the slit can be deformed so as to spread in the stacking direction. By this action, a situation is obtained in which one electrode terminal fitted in one through hole can move in the stacking direction with respect to the other electrode terminal fitted in the other through hole. For this reason, when the bus bar is press-fitted into the electrode terminal to be connected, the bus bar can be moved in the direction in which the through holes are arranged (stacking direction), so that the position can be easily adjusted in the connection process. Therefore, even when variations occur in each pitch dimension between a plurality of electrode terminals to be connected in a battery pack, smooth connection can be achieved by using a bus bar having a specific configuration that can cope with these variations. Productivity can be improved.

  According to a fifth aspect of the present invention, in the battery pack according to any one of the first to fourth aspects, one of the first through hole (51) and the second through hole (51A) is a stacking direction of the battery cells (X ) In the shape of a long slot. According to this invention, when one through-hole of both the through-holes is a long hole shape, when connecting the electrode terminal of a connection object by a bus bar, one electrode which fits in a long-hole-shaped through hole A situation is obtained in which the terminal is movable in the stacking direction with respect to the electrode terminal fitted in the other through hole. Thereby, when the bus bar is press-fitted into the electrode terminal to be connected, the bus bar can be moved in the direction in which the through holes are arranged (stacking direction), so that the position can be easily adjusted in the connection process. In addition, even when variations occur in the pitch dimensions between the plurality of electrode terminals to be connected in the battery pack, smooth connection can be achieved by using a bus bar having a specific configuration capable of dealing with these variations. Can improve productivity.

  A sixth aspect of the present invention is the battery pack according to any one of the first to fifth aspects, wherein the first through hole (53) and the second through hole (53A) are formed by burring. And According to this invention, since the shape of rising the inner peripheral edge of the first through hole and the second through hole from the surface of the bus bar can be formed, the contact area between the bus bar and the press-fitted electrode terminal can be expanded, The force with which the bus bar holds the electrode terminal can be improved.

Claim 7 is a connection of battery cells (10) having a positive electrode terminal and a negative electrode terminal projecting from the outer case (12), and a plurality of battery cells (10) adjacent to each other in the stacking direction (X). The invention relates to a battery pack (1) configured to be energized by connecting the target terminals using a bus bar (60),
The bus bar has a curved portion (61) formed in the center and deformed by a compressive force from both sides, a pair of leg portions (63) extending horizontally from the curved portion to both sides, and an opening into which an electrode terminal is fitted. And a pair of terminal support portions (62) formed on each of the pair of leg portions,
The terminal to be connected is fitted to each of the pair of terminal support portions to deform the curved portion and compress in the stacking direction (X), and is connected and fixed to the bus bar by receiving a reaction force from the curved portion. It is characterized by.

  According to the present invention, when the bus bar is fitted between the electrode terminals to be connected in the adjacent battery cells, the bending portion is deformed by receiving the compressive force in the stacking direction and the reaction force from the bending portion is connected to the connection target. Therefore, the terminals can be firmly held by the pair of terminal support portions. The bus bar can hold the electrode terminal firmly by the action of the bus bar. Therefore, compared with the inter-terminal connection process by nut tightening or bolt tightening of the prior art described above, it is possible to significantly reduce the man-hours for inter-terminal connection and to provide a battery pack with improved productivity.

The present invention provides a connection between battery cells adjacent to each other in the stacking direction (X) by stacking a plurality of battery cells (10) each having an electrode terminal (11) composed of a positive electrode terminal and a negative electrode terminal protruding from the outer case (12). The invention relates to a battery pack (1) configured to be energized by connecting the target terminals using a bus bar (70),
The bus bars are formed on both ends of the battery cell in the stacking direction (X) and are formed on each of the pair of terminal support portions (71) supporting the electrode terminals and the inner peripheral portions of the pair of terminal support portions. A semicircular opening (72) into which the terminal fits, and a connecting portion (73) connecting the pair of terminal support portions,
The terminals to be connected are fitted to the respective semicircular openings to be deformed so as to widen the pair of terminal support portions and pulled in the stacking direction (X) and receive a reaction force from the pair of terminal support portions. It is characterized by being connected and fixed to the bus bar.

  According to the present invention, when the bus bar is fitted between the electrode terminals to be connected in the adjacent battery cells, the pair of terminal support portions are deformed by receiving a tensile force in the stacking direction from each terminal to be connected. Since the reaction force from the pair of terminal support portions is applied to each terminal to be connected, the terminals can be firmly held by the pair of terminal support portions. The bus bar can hold the electrode terminal firmly by the action of the bus bar. Therefore, compared with the inter-terminal connection process by nut tightening or bolt tightening of the prior art described above, it is possible to significantly reduce the man-hours for inter-terminal connection and to provide a battery pack with improved productivity.

Claim 9 is a battery pack (1) configured by stacking a plurality of battery cells (10) each having an electrode terminal (11) composed of a positive electrode terminal and a negative electrode terminal protruding from an outer case (12). (X) is an invention relating to a connection method between electrode terminals for connecting between terminals to be connected in battery cells adjacent to (X) so as to be energized using a plurality of bus bars (50),
Each of the bus bars is formed with a first through hole (51) and a second through hole (51A) penetrating in the thickness direction with an inner diameter dimension equal to or less than the outer shape of the battery cell terminal,
A bus bar arranging step of arranging a bus bar so that a positive electrode terminal and a negative electrode terminal to be connected to adjacent battery cells can be press-fitted into the first through hole and the second through hole, respectively, and a positive electrode terminal and a negative electrode to be connected A press-fitting jig (20) formed with a plurality of terminal insertion paths (23) at corresponding positions where terminals can be inserted is arranged in the bus bar arrangement process from the state where the positive terminal and the negative terminal are inserted into the terminal insertion path. And a bus bar connecting step of pressing and fixing each bus bar and the electrode terminal.

  According to the present invention, in the bus bar arranging step, the bus bars are arranged so that each electrode terminal can be press-fitted into the predetermined first through hole and the second through hole, respectively, and then each electrode terminal is inserted into the terminal insertion path. In this state, a press-fitting jig is pushed into the bus bar, and a bus bar connecting step for press-fitting each bus bar and the electrode terminal is performed. By such a process, each through hole is expanded by the press-fitting of the electrode terminal, so that the effect of firmly holding the electrode terminal on the inner peripheral wall surface of each through-hole can be achieved with a single press-fitting to a large number of press-fitting connections. Can be obtained at the same time. Therefore, compared to the above-described conventional terminal-to-terminal connection method by nut tightening or bolt tightening, it is possible to provide a connection method between electrode terminals that can significantly reduce the man-hours and improve the productivity.

  According to Claim 10, the bus bar (50) used for the connection method between the electrode terminals of Claim 9 is comprised with the elastic body, It is characterized by the above-mentioned. According to the present invention, in the bus bar connecting step, the bus bars easily extend and deform in the direction in which the through holes are arranged, and the bus bar connecting step can be performed more smoothly.

  According to claim 11, each of the first through hole (51) and the second through hole (51A) is included in the bus bar (50) used in the connection method between the electrode terminals according to claim 9 or claim 10. A slit (52) extending outward from the inner peripheral edge is formed. According to the present invention, in the bus bar connecting step, each through hole can be easily enlarged by deformation of the slit, and the bus bar connecting step can be performed more smoothly.

  According to claim 12, in the connection method between the electrode terminals according to claim 11, the slit extends outward from the inner peripheral edge in a direction (Y) perpendicular to the stacking direction (X) of the battery cells. It is characterized by. According to this invention, the slit extending in the direction perpendicular to the stacking direction is formed in the inner peripheral edge of each of the first through hole and the second through hole, so that in the bus bar arranging step and the bus bar connecting step The slit can be deformed so as to spread in the stacking direction. By this action, a situation is obtained in which one electrode terminal fitted in one through hole can move in the stacking direction with respect to the other electrode terminal fitted in the other through hole. For this reason, when the bus bar is press-fitted into the electrode terminal to be connected, the bus bar can be moved in the direction in which the through holes are arranged (stacking direction), so that it is easy to adjust the position in the connection process, contributing to a smooth connection. Productivity can be improved. Further, even when variations occur in the pitch dimensions between the plurality of electrode terminals to be connected in the battery pack, it is possible to provide a connection method between the electrode terminals that can cope with these variations.

  According to Claim 13, in the connection method between the electrode terminals according to Claims 9 to 12, one of the first through hole (51) and the second through hole (51A) is the stacking direction of the battery cells. (X) is formed in a long slot shape. According to the present invention, one electrode terminal that fits into the long hole-shaped through hole in the bus bar arranging step or the bus bar connecting step is formed through the other through hole because one through hole of both the through holes has a long hole shape. A situation is obtained in which the electrode terminals fitted in the holes are movable in the stacking direction. As a result, when the bus bar is press-fitted into the electrode terminal to be connected, the bus bar can be moved in the direction in which the through-holes are arranged (stacking direction), so that it is easy to adjust the position in the connection process, contributing to a smooth connection. Productivity can be improved. Further, even when variations occur in the pitch dimensions between the plurality of electrode terminals to be connected in the battery pack, it is possible to provide a connection method between the electrode terminals that can cope with these variations.

  The reference numerals in parentheses of the above means are an example showing the correspondence with the specific means described in the embodiments described later.

It is a perspective view which shows the connection structure between the terminals of the battery cell which concerns on the battery pack of 1st Embodiment of this invention. It is a perspective view of the bus bar used for the inter-terminal connection structure of the battery cell of the first embodiment. It is a top view explaining the relationship between the bus-bar which concerns on 1st Embodiment, and a rod-shaped electrode terminal. It is a perspective view for demonstrating the press injection process which press-fits a bus-bar to an electrode terminal. It is the perspective view which showed the press-fitting jig used for the process of press-fitting a bus bar into an electrode terminal. It is the fragmentary sectional view which showed the cross section of the terminal insertion path which inserts an electrode terminal about the press-fitting jig | tool of FIG. It is a perspective view for demonstrating the press-fit process using the press-fit jig | tool which is another form of the press-fit jig shown in FIG. It is the perspective view which showed the press-fitting jig | tool which is another form of the press-fitting jig | tool shown in FIG. FIG. 9 is a partial cross-sectional view showing a cross section of a terminal insertion path for inserting an electrode terminal in the press-fitting jig of FIG. 8. It is a perspective view which shows the bus-bar used for the terminal-cell connection structure of the battery cell which concerns on the battery pack of 2nd Embodiment of this invention. It is a top view explaining the relationship between the bus-bar which concerns on 2nd Embodiment, and a rod-shaped electrode terminal. It is a perspective view which shows the bus bar used for the connection structure between the terminals of the battery cell which concerns on the battery pack of 3rd Embodiment of this invention. It is a top view explaining the relationship between the bus-bar which concerns on 3rd Embodiment, and a rod-shaped electrode terminal. It is a front view which shows the bus bar of 3rd Embodiment. It is a perspective view which shows the bus-bar used for the terminal-cell connection structure of the battery cell which concerns on the battery pack of 4th Embodiment of this invention. It is a perspective view which shows the bus bar of 4th Embodiment. It is a front view which shows the bus bar of 4th Embodiment. It is a top view explaining the relationship between the bus-bar which concerns on 4th Embodiment, and a rod-shaped electrode terminal. It is a perspective view which shows the bus bar used for the connection structure between the terminals of the battery cell which concerns on the battery pack of 5th Embodiment of this invention. It is a perspective view which shows the bus bar of 5th Embodiment. It is a top view which shows the bus-bar of 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 show that combinations are possible in each embodiment, but also combinations of the embodiments even if they are not specified, unless there is a particular problem with the combination. Is also possible.

(First embodiment)
In the battery pack 1 of the first embodiment to which the present invention is applied, a plurality of battery cells 10 are arranged side by side so that their side surfaces face each other, and electrode terminals of different polarities of adjacent battery cells 10 are connected by a bus bar 50. It is an aggregate of battery cells 10 that are electrically connected in series and integrated.

  The battery pack 1 is used in, for example, a hybrid vehicle that uses a traveling drive source by combining an internal combustion engine and a motor driven by electric power charged in the battery, an electric vehicle that uses a motor as a travel drive source, and the like. The battery constituting the battery pack is, for example, a nickel metal hydride secondary battery, a lithium ion secondary battery, or an organic radical battery, and the space between the rear seat and the trunk room under the seat of the automobile in a state of being housed in the housing, It is placed in the space between the driver seat and the passenger seat.

  1st Embodiment which is one Embodiment of this invention is described using FIGS. 1-3. FIG. 1 is a perspective view showing an inter-terminal connection structure of battery cells according to the battery pack of the first embodiment, and shows a state where two battery cells 10 are simply connected. FIG. 2 is a perspective view of the bus bar 50 used in the inter-terminal connection structure of the battery cell 10 according to the first embodiment. FIG. 3 is a plan view illustrating the relationship between the bus bar 50 and the rod-shaped electrode terminal 11 according to the first embodiment.

  The battery pack 1, which is an assembly of a plurality of battery cells 10, is controlled by electronic components (not shown) used for charging and discharging or temperature control of the plurality of battery cells 10, and blows air by a blower member (not shown). In response, each battery cell 10 is cooled. The battery pack 1 is formed by stacking a plurality of battery cells 10 electrically connected in series by a bus bar 50 and further constraining them by a restraining means, and is housed in a housing (not shown). . The above electronic components are a DC / DC converter, a motor for driving a blowing member, an electronic component controlled by an inverter, various electronic control devices, and the like, and are adjusted by, for example, a power element that is a switching power supply device. It is a part operated by electric power.

  The housing is provided with an attachment portion for fixing the housing to the vehicle side by bolting or the like, and an equipment storage box (not shown). The device box is configured to be communicable with a battery monitoring unit (not shown) to which detection results from various sensors for monitoring a battery state (for example, voltage, temperature, etc.) are input, and DC / DC. A control device that controls the power transfer of the converter and also controls the drive of the motor of the blower member, a wire harness that connects each device, and the like are housed. The battery monitoring unit is a battery ECU (battery electronic control unit) that monitors the state of each battery cell 10, and is connected to the battery pack 1 by a number of wires.

  Each battery cell 10 constituting the laminate includes an electrode terminal 11 (a positive electrode terminal and a negative electrode terminal) protruding from the upper surface of the outer case 12 of the battery cell 10. The electrode terminals 11 connected between the adjacent battery cells 10 are connected by a bus bar 50 which is a metal plate having excellent electrical conductivity and also an elastic body having elasticity. The plurality of battery cells 10 constituting one laminated body are connected so as to be energized by the corresponding number of bus bars 50. In other words, all the battery cells 10 of the battery pack 1 are electrically connected in series via the bus bar 50 so that the current flows in a zigzag shape or a meandering shape. Then, power is transferred from the total terminal portions (not shown) arranged at both ends of the laminate that can be energized by the bus bar 50. In addition, the bus bar 50 being an elastic body means that the bus bar 50 is made of a shape or material that can expand and contract in the stacking direction X and the direction Y perpendicular to the stacking direction X.

  In the inter-terminal connection structure of the battery cell 10 according to the battery pack 1 of the first embodiment, the bus bar 50 includes two first through holes 51 and second through holes 51A penetrating in the thickness direction, and the first through holes. 51 and a slit 52 extending outward from the inner peripheral edge of the second through hole 51A are formed. The first through hole 51 is formed on one side of the arrangement direction of the electrode terminals 11 to be connected (also referred to as the stacking direction X of the battery cells 10), and the second through hole 51A is the other side of the stacking direction X. Is formed.

  The first through hole 51 is a circular opening. The slit 52 is formed to extend outward from the inner peripheral edge of the first through hole 51 in the stacking direction X of the battery cells 10. Further, one slit 52 is formed at each end of the inner peripheral edge of the first through hole 51 in the battery cell stacking direction. As shown in FIG. 3, the first through hole 51 is formed so that the inner diameter dimension of the first through hole 51 is equal to or slightly smaller than the outer dimension of the electrode terminal 11 indicated by a two-dot chain line.

  The second through hole 51A is an elongated hole-like opening that is long in the battery cell stacking direction. The slits 52 are formed so as to extend outward from the inner peripheral edge of the elongated second through hole 51A, and one slit 52 is formed at each end in the battery cell stacking direction at the inner peripheral edge of the second through hole 51A. Yes. As shown in FIG. 3, the second through hole 51 </ b> A has a width dimension in the minor axis direction of the second through hole 51 </ b> A that is equal to or slightly smaller than the outer dimension of the electrode terminal 11 indicated by a two-dot chain line. Is formed. The bus bar 50 can be formed of a metal having excellent conductivity.

  According to the bus bar 50, since the second through hole 51A into which the one electrode terminal 11 is inserted has a long hole shape, even if there is a variation in the interval between the electrode terminals 11, the two electrodes to be connected Both of the electrode terminals 11 can be simultaneously inserted into the bus bar 50 while sliding the bus bar 50 in the arrangement direction of the terminals 11 (battery cell stacking direction), and a smooth inter-terminal connection process can be performed.

  When the electrode terminals 11 of the adjacent battery cells 10 are electrically connected, the bus bar 50 is viewed from above so that the rod-shaped electrode terminal 11 is press-fitted into each of the first through hole 51 and the second through hole 51A of the bus bar 50. Move and push in. At this time, the inner peripheral wall surface of the first through hole 51 and the inner peripheral wall surface of the second through hole 51 </ b> A are spread by the electrode terminal 11 and come into close contact with at least a part of the outer peripheral surface of the electrode terminal 11. That is, the inner peripheral wall surface of the first through hole 51 and the inner peripheral wall surface of the second through hole 51A have inner diameters up to positions where they are in close contact with the outer peripheral surface (circular two-dot chain line) of the electrode terminal 11 illustrated in FIG. It expands and deforms.

  As described above, the bus bar 50 has a space between terminals that firmly holds the electrode terminal 11 and does not require a process such as screw tightening by press-fitting the electrode terminal 11 into the first through hole 51 and the second through hole 51A. Realize the connection process. Therefore, for example, even when the bus bar is not formed with a slit 52, when the electrode terminal 11 to be connected to the battery cell 10 is fitted in each of the first through hole 51 and the second through hole 51A of the bus bar, Each through-hole 51, 51A is expanded by press-fitting, and the outer peripheral surface of the electrode terminal 11 of the battery cell 10 can be firmly held by the inner peripheral wall surface of each through-hole 51, 51A. The bus bar is firmly held by the electrode terminal 11 by the action of the bus bar. Therefore, it is possible to obtain the battery pack 1 that reduces the man-hours for connecting the terminals and improves the productivity.

  Moreover, when the electrode terminal 11 used as the connection object of the battery cell 10 fits in each of the 1st through-hole 51 and the 2nd through-hole 51A of the bus bar 50, since the bus bar 50 is comprised with the elastic body, it is connected. When the bus bar 50 is press-fitted into the target electrode terminal 11, the bus bar 50 can be extended and deformed in the direction in which the through holes are arranged (stacking direction X). For this reason, even when variations occur in each pitch dimension between the plurality of electrode terminals 11 to be connected in the manufacturing process, since the bus bar 50 can cope with these variations, smooth connection can be performed, It can contribute to the improvement of productivity.

  Further, when the electrode terminal 11 to be connected to the battery cell 10 is fitted in each of the first through hole 51 and the second through hole 51A of the bus bar 50, the slit 52 is formed in the first through hole 51 and the second through hole 51A. Therefore, each of the through holes 51 and 51A can be easily enlarged along with the deformation of the slit 52, and the battery cell 10 is formed on the inner peripheral wall surface of each of the through holes 51 and 51A. The outer peripheral surface of the electrode terminal 11 can be firmly held. Due to the unique action of the bus bar 50, the bus bar 50 is firmly held by the electrode terminal 11.

  One of the first through hole 51 and the second through hole 51 </ b> A is formed in a long hole shape that is long in the stacking direction X of the battery cells 10. According to this configuration, when one of the first through hole 51 and the second through hole 51A is a long hole, when the electrode terminal 11 to be connected is connected by the bus bar 50, a long hole is formed. One electrode terminal 11 that fits in the through hole is movable in the stacking direction X with respect to the electrode terminal 11 that fits in the other through hole. Since the movement in the stacking direction X is allowed in this way, the bus bar 50 can be moved in the direction in which the through holes are arranged when the bus bar 50 is press-fitted into the electrode terminal 11 to be connected. Position adjustment can be handled easily.

  Further, even when variations occur in the pitch dimensions between the plurality of electrode terminals 11 to be connected in the manufacturing process, the bus bar 50 has a unique configuration capable of dealing with these variations, so that smooth connection can be achieved. Can be implemented and can contribute to the improvement of productivity.

  Next, the connection method between the electrode terminals 11 in the manufacturing method of the battery pack 1 will be further described. First, the first connection method will be described with reference to FIGS. FIG. 4 is a perspective view for explaining a press-fitting process for press-fitting the bus bar 50 into the electrode terminal 11. FIG. 5 is a perspective view showing the press-fitting jig 20 used in the step of press-fitting the bus bar 50 into the electrode terminal 11. FIG. 6 is a partial cross-sectional view showing a cross section of the terminal insertion path 23 for inserting the electrode terminal 11 in the press-fitting jig 20 of FIG.

  The connection method between electrode terminals has a bus-bar arrangement | positioning process and a bus-bar connection process. The bus bar arranging step is a step of arranging the bus bar 50 so that the positive electrode terminal and the negative electrode terminal to be connected with respect to the adjacent battery cells 10 are press-fitted into the first through hole 51 and the second through hole 51A, respectively. In the bus bar connecting step, as shown in FIG. 4, the press fitting jig 20 held by a chuck or the like is inserted in the terminal insertion path 23 from the state in which the positive terminal and the negative terminal are inserted into the bus bar arranging step. In this step, each bus bar 50 and the corresponding electrode terminal 11 are press-fitted and fixed.

  As shown in FIGS. 5 and 6, the press-fitting jig 20 is formed with a plurality of terminal insertion paths 23 having a passage size into which the positive terminal and the negative terminal can be inserted. The number of terminal insertion paths 23 is the same as the number of electrode terminals 11 that can be press-fitted at once by the press-fitting jig 20. That is, the press-fitting jig 20 may be configured to complete the connection of the bus bars 50 in all the battery cells constituting the battery pack 1 at once by press-fitting by the press-fitting jig 20, or divided into several times. You may comprise so that it may be completed by the press injection by the press fitting jig | tool 20. FIG.

  The press-fitting jig 20 is formed in a plate shape by integrally forming a resin member 22 in which a terminal insertion path 23 is formed and a metal member 21 that supports the resin member 22 from the back side of the resin member 22 and reinforces the resin member 22. Yes. The resin member 22 has a plate shape, and a plurality of terminal insertion paths 23 that form a cylindrical bottomed recess from the plate-like surface are formed. Each terminal insertion path 23 is provided at a corresponding position where a positive electrode terminal and a negative electrode terminal to be connected can be inserted in the bus bar connection step.

  Next, the second connection method will be described with reference to FIGS. FIG. 7 is a perspective view for explaining a press-fitting process for press-fitting the bus bar 50 into the electrode terminal 11. FIG. 8 is a perspective view showing a press-fitting jig 20 </ b> A used in the step of press-fitting the bus bar 50 into the electrode terminal 11. FIG. 9 is a partial cross-sectional view showing a cross section of a terminal insertion path 23A for inserting the electrode terminal 11 in the press-fitting jig 20A of FIG.

  The second connection method is different from the first connection method in that the terminal insertion path 23A is not a bottomed recess, but is formed by a through-hole penetrating the press-fitting jig 20A in the thickness direction as shown in FIGS. It differs in that it is formed. The press-fitting jig 20A is formed in a plate shape by integrally forming a resin member 22A in which a terminal insertion path 23A is formed and a metal member 21A that supports the resin member 22A by supporting it from the back side of the resin member 22A. Yes. With such a configuration, in the bus bar connecting step, when the press-fitting jig 20A held by a chuck or the like is pushed into the bus bar 50, it is determined whether or not each electrode terminal 11 is inserted into each terminal insertion path 23. Visible from the side.

  As described above, according to the connection method between the electrode terminals 11, after the bus bar 50 is arranged in the bus bar arrangement step so that each electrode terminal 11 can be press-fitted into the predetermined first through hole 51 and the second through hole 51A, respectively. Then, the bus bar connecting step is performed in which the press fitting jigs 20 and 20A are pushed into the bus bar 50 with the respective electrode terminals 11 inserted into the terminal insertion paths 23 and 23A to press fit and connect the respective bus bars 50 and the electrode terminals 11. . By such a process, the effect of firmly holding the electrode terminal 11 on the inner peripheral wall surface of each through hole 51, 51A due to the enlargement of each through hole 51, 51A by press-fitting the electrode terminal 11 into the bus bar 50. It is possible to provide a plurality of press-fitting connection parts simultaneously by a single press-fitting process. Therefore, the man-hours can be greatly reduced and productivity can be expected to be improved as compared with the above-described conventional terminal-to-terminal connection method using nut fastening or bolt fastening.

  Further, since the bus bar 50 is made of an elastic body, the bus bar 50 is easily deformed by extending in the direction in which the through holes 51 and 51A are arranged in the bus bar connecting step. Therefore, the press-fitting in the bus bar connection process can be performed more smoothly.

  In addition, the bus bar 50 is formed with slits 52 extending outward from the inner peripheral edge portions of the first through holes 51 and the second through holes 51A. The hole can be easily expanded. Therefore, the press-fitting in the bus bar connection process can be performed more smoothly.

  Further, also in the connection method between the electrode terminals 11, one of the first through hole 51 and the second through hole 51 </ b> A is formed in an elongated hole shape in the stacking direction X of the battery cells 10. In the bus bar arranging step and the bus bar connecting step, one electrode terminal 11 fitted into the long hole-like through hole can move in the stacking direction X with respect to the electrode terminal 11 fitted into the other through hole. Accordingly, the bus bar 50 can be moved in the stacking direction X when the bus bar 50 is press-fitted into the electrode terminal 11 to be connected. Therefore, it is easy to adjust the position in the connection step, and it can further contribute to the smooth connection of the bus bar 50.

  Also in the connection method between the electrode terminals 11, when the slit 52 extends outward from the inner peripheral edge in the direction Y perpendicular to the stacking direction X of the battery cells 10, the bus bar arranging step and the bus bar connecting step The slit 52 can be easily deformed so as to spread in the stacking direction X. By this action, one electrode terminal 11 fitted in one through hole can be moved in the stacking direction X with respect to the other electrode terminal 11 fitted in the other through hole. Accordingly, when the bus bar 50 is press-fitted into the electrode terminal 11 to be connected, the bus bar can be moved in the stacking direction X, so that it is easy to adjust the position in the connection process, and further contribute to the smooth connection of the bus bar 50. it can.

(Second Embodiment)
In the second embodiment, a bus bar 50A, which is another form of the first embodiment, will be described with reference to FIGS. FIG. 10 is a perspective view showing a bus bar 50A used in the inter-terminal connection structure of the battery cell 10 according to the battery pack of the second embodiment. FIG. 11 is a plan view for explaining the relationship between the bus bar 50 </ b> A and the rod-shaped electrode terminal 11.

  As shown in FIGS. 10 and 11, the bus bar 50 </ b> A of the second embodiment has two first through holes 51 that penetrate in the thickness direction and are aligned in the stacking direction X of the battery cells 10, and each first penetration. A slit 52 </ b> A extending outward from the inner peripheral edge of the hole 51 is formed.

  The first through hole 51 is a circular opening. The slit 52 </ b> A is formed to extend outward from the inner peripheral edge of the first through hole 51 in a direction Y perpendicular to the stacking direction X of the battery cells 10. Further, one slit 52 </ b> A is formed at each end portion in the perpendicular direction Y at the inner peripheral edge of the first through hole 51. As shown in FIG. 11, the first through hole 51 is formed so that the inner diameter dimension of the first through hole 51 is equal to or slightly smaller than the outer dimension of the electrode terminal 11 indicated by a two-dot chain line.

  According to the bus bar 50A, the slits 52A are formed in the two first through holes 51 so as to extend outward in the direction Y perpendicular to the battery cell stacking direction X. Therefore, the electrode terminal 11 to be connected is connected to the bus bar 50A. When connecting the slit 52A, the slit 52A can be deformed so as to spread in the stacking direction X. By this action, one electrode terminal 11 fitted in one through hole can be moved in the stacking direction X with respect to the other electrode terminal 11 fitted in the other through hole. Accordingly, when the bus bar 50A is press-fitted into the electrode terminal 11 to be connected, the bus bar 50A can be moved in the direction in which the through holes are arranged (stacking direction X). The 50A connection can further contribute.

  In addition, even if there is a variation in the distance between the electrode terminals 11, the first through holes 51 are likely to expand in the stacking direction X of the battery cells 10 as described above, and thus the position of the bus bar 50 </ b> A with respect to the electrode terminals 11. Adjustments can be made. For this reason, the smooth connection between terminals can be implemented. Moreover, according to the bus bar 50A, it is also possible to reduce the press-fit load due to the application of a tensile force when the bus bar 50A is assembled to the electrode terminal 11.

(Third embodiment)
In 3rd Embodiment, the bus-bar 50B which is another form with respect to 1st Embodiment is demonstrated with reference to FIGS. FIG. 12 is a perspective view showing a bus bar 50B used in the inter-terminal connection structure for battery cells according to the battery pack of the third embodiment. FIG. 13 is a plan view for explaining the relationship between the bus bar 50B and the rod-shaped electrode terminals. FIG. 14 is a front view showing the bus bar 50B. 12 to 14, the same reference numerals as those used in the drawings described in the first embodiment denote the same elements.

  As shown in FIGS. 12 to 14, two first through holes 53 and second through holes 53 </ b> A are formed in the bus bar 50 </ b> B of the third embodiment by burring. According to this configuration, it is possible to form a shape in which the inner peripheral edge portions of the first through hole 53 and the second through hole 53A are raised from the surface of the bus bar 50B. For this reason, the contact area of bus bar 50B and electrode terminal 11 can be expanded. Therefore, the force with which the bus bar 50B holds the electrode terminal 11 can be improved, and a more reliable connection structure of the electrode terminal 11 can be provided.

(Fourth embodiment)
4th Embodiment demonstrates the connection structure between the terminals of the battery cell 10 which is another form with respect to 1st Embodiment with reference to FIGS. FIG. 15 is a perspective view showing a bus bar 60 used in the inter-terminal connection structure of the battery cell 10 according to the battery pack 1 of the fourth embodiment. 16 is a perspective view showing the bus bar 60, and is a front view showing the bus bar 60 of FIG. FIG. 18 is a plan view for explaining the relationship between the bus bar 60 and the rod-shaped electrode terminal 11. In FIG. 15, the same reference numerals as those in the drawing described in the first embodiment denote the same elements.

  In the inter-terminal connection structure of the battery cell 10 according to the battery pack 1 of the fourth embodiment, the bus bar 60 includes a curved portion 61 formed in the center and a pair of U-shaped horizontally extending from the curved portion 61 to the left and right respectively. The leg part 63 and the notch part 62 (terminal support part) formed in each of a pair of leg part 63 and having a semi-track-like opening into which the electrode terminal 11 is fitted are configured. ing. As shown in FIG. 18, the electrode terminals 11 are arranged in the battery cell stacking direction indicated by a two-dot chain line in a natural state in which the notch portions 62 formed on both sides of the curved portion 61 are not subjected to external force. The bus bar 60 is formed to be slightly smaller than the pitch dimension.

  When the bus bar 60 is disposed between the electrode terminals 11 to be connected in the battery cell stacking direction, the bending portion 61 is elastically deformed when a compressive force is applied to the bus bar 60 in the battery cell stacking direction, and the compression is performed. Demonstrate elastic force against the force. The two leg portions 63 serve to hold the electrode terminals 11 when the electrode terminals 11 are fitted into the respective cutout portions 62. In other words, the bus bar 60 is held between the electrode terminals of the battery cells 10 to be stacked, so that the bent portion 61 tends to be restored to the original shape in order to spread in the battery cell stacking direction. The bus bar 60 holds the electrode terminals 11 on both sides by using the elastic force generated at this time.

  The bus bar 60 has a curved portion 61 formed in the center and deformed by a compressive force from both sides, a pair of leg portions 63 extending horizontally from the curved portion 61 to both sides, and an opening into which the electrode terminal 11 is fitted. And a pair of cutout portions 62 (terminal support portions) formed in each of the pair of leg portions 63. The electrode terminal 11 to be connected is fitted to each of the pair of terminal support portions to deform the bending portion 61 and compress in the stacking direction X, and is connected and fixed to the bus bar 60 by receiving a reaction force from the bending portion 61. ing.

  According to this configuration, when the bus bar 60 is fitted between the electrode terminals 11 to be connected in the battery cells 10 arranged adjacent to each other, the bending portion 61 is deformed by receiving the compressive force in the stacking direction X, and from the bending portion 61. Since the reaction force is applied to each electrode terminal 11 to be connected, each electrode terminal 11 can be firmly held by the pair of terminal support portions. Due to the action of the bus bar 60, the bus bar 60 can firmly hold the electrode terminal 11, so that the number of man-hours for inter-terminal connection can be greatly reduced as compared with the inter-terminal connection step by nut tightening or bolt tightening of the prior art. Therefore, productivity can be improved.

  As described above, the bus bar 60 exerts an elastic force against the compressive force acting on itself and holds the electrode terminals 11 on both sides, thereby holding the electrode terminals 11 firmly and eliminating the need for a process such as screw tightening. The inter-terminal connection process is realized. Therefore, according to the fourth embodiment, it is possible to obtain the battery pack 1 that reduces the man-hours for connecting the terminals and improves the productivity.

(Fifth embodiment)
5th Embodiment demonstrates the connection structure between the terminals of the battery cell 10 which is another form with respect to 1st Embodiment with reference to FIGS. FIG. 19 is a perspective view showing a bus bar 70 used in the inter-terminal connection structure of the battery cell 10 according to the battery pack 1 of the fifth embodiment. FIG. 20 is a perspective view showing the bus bar 70. FIG. 21 is a plan view for explaining the relationship between the bus bar 70 and the rod-shaped electrode terminal 11. In FIG. 19, the same reference numerals as those in the drawing described in the first embodiment denote the same elements.

  In the inter-terminal connection structure of the battery cell 10 according to the battery pack 1 of the fifth embodiment, the bus bar 70 includes a pair of semicircular terminal support portions 71 formed at both ends, and a semicircular terminal support portion 71. A pair of semicircular openings 72 formed in the inner peripheral portion of each of the two and a linear connecting portion 73 connecting the terminal support portions 71 at both ends are formed in a C shape. As shown in FIG. 21, the pitch dimension of the pair of semicircular openings 72 formed in the terminal support portions 71 on both sides is a natural state in which no external force is applied, and the battery cell stacking direction indicated by a two-dot chain line The bus bar 70 is formed so as to be slightly smaller than the pitch dimension of the electrode terminals 11 arranged in a row.

  When the bus bar 70 is disposed so as to hold about a half circumference of the outer peripheral surface of the electrode terminal 11 to be connected in the battery cell stacking direction, the terminal support 71 pulls in the battery cell stacking direction with respect to the bus bar 60. When it is applied, it is elastically deformed and exhibits an elastic force against the pulling force. The two terminal support portions 71 serve to hold the electrode terminals 11 when the electrode terminals 11 are fitted in the respective semicircular openings 72. That is, the bus bar 70 holds both the electrode terminals 11 by applying a compressive force to the electrode terminals of the battery cells 10 to be stacked so as to narrow the space between both the electrode terminals 11 (between the battery cells 10). It is.

  The bus bar 70 of the fifth embodiment is formed on both end sides in the stacking direction X of the battery cells 10, and a pair of terminal support portions 71 that respectively support the electrode terminals 11, and an inner peripheral portion of each of the pair of terminal support portions 71. And a semicircular opening 72 into which the electrode terminal 11 is fitted, and a connecting portion 73 that connects the pair of terminal support portions 71. The electrode terminals 11 to be connected are fitted to the respective semicircular openings 72 to be deformed so as to expand the pair of terminal support portions 71 and pulled in the stacking direction X, and the reaction force from the pair of terminal support portions 71. Accordingly, the connection is fixed to the bus bar 70.

  According to this configuration, when the bus bar 70 is fitted between the electrode terminals 11 to be connected in the adjacent battery cells 10, the pair of terminal support portions 71 are pulled in the stacking direction X from each electrode terminal 11 to be connected. The electrode terminal 11 can be firmly held by the pair of terminal support portions 71 since the reaction force from the pair of terminal support portions 71 is applied to each electrode terminal 11 to be connected, while being deformed by receiving the force. Due to the action of the bus bar 70, the bus bar 70 can firmly hold the electrode terminal 11, so that the number of man-hours for inter-terminal connection can be greatly reduced as compared with the inter-terminal connection step by nut tightening or bolt tightening of the prior art. Therefore, productivity can be improved.

  In this way, the bus bar 70 holds the electrode terminals 11 firmly by tightening the screws by exerting an elastic force to bring the electrode terminals 11 on both sides close to each other against a pulling force acting on itself. An inter-terminal connection process that eliminates the need for such processes is realized. Therefore, according to the fifth embodiment, it is possible to obtain the battery pack 1 that reduces man-hours for connection between terminals and improves productivity.

DESCRIPTION OF SYMBOLS 1 ... Battery pack 10 ... Battery cell 11 ... Electrode terminal (terminal)
DESCRIPTION OF SYMBOLS 12 ... Outer case 20, 20A ... Press-fit jig 23, 23A ... Terminal insertion path 50, 50A, 50B, 60, 70 ... Bus bar 51, 53 ... 1st through-hole (through-hole)
51A, 53A ... second through hole (through hole)
52, 52A ... Slit 61 ... Bending part 62 ... Notch part (terminal support part)
63 ... Leg portion 71 ... Terminal support portion 72 ... Semicircular opening 73 ... Connection portion X ... Lamination direction

Claims (13)

A plurality of battery cells (10) having a positive electrode terminal and a negative electrode terminal (11) projecting from the outer case (12) are stacked, and the battery cell (10) adjacent to the stacking direction (X) is to be connected. A battery pack (1) configured to connect between terminals using a bus bar (50) and be energized,
The bus bar is formed with a first through hole (51) and a second through hole (51A) having an inner diameter dimension equal to or smaller than the outer dimension of the terminal of the battery cell and penetrating in the thickness direction. And
The terminal to be connected is fitted into each of the first through hole (51) and the second through hole (51A), and the terminal to be connected is connected and fixed by the bus bar. Battery pack to play.   The battery pack according to claim 1, wherein the bus bar (50) is made of an elastic body.   The said bus-bar (50) is formed with the slit (52) extended outside from each inner peripheral edge part of said 1st through-hole (51) and said 2nd through-hole (51A), It is characterized by the above-mentioned. The battery pack according to claim 1 or 2.   The battery pack according to claim 3, wherein the slit (52A) extends outward from the inner peripheral edge in a direction (Y) perpendicular to the stacking direction (X) of the battery cells.   One of the first through hole (51) and the second through hole (51A) is formed in a long hole shape in the stacking direction (X) of the battery cells. Item 5. The battery pack according to any one of items 4.   The battery pack according to any one of claims 1 to 5, wherein the first through hole (53) and the second through hole (53A) are formed by burring. A plurality of battery cells (10) having a positive electrode terminal and a negative electrode terminal (11) projecting from the outer case (12) are stacked, and the battery cell (10) adjacent to the stacking direction (X) is to be connected. A battery pack (1) configured to connect between terminals using a bus bar (60) and to be energized,
The bus bar is formed in the center and deformed by a compressive force from both sides, a pair of leg portions (63) extending horizontally from the curved portion to both sides, and an opening into which the electrode terminal is fitted. And a pair of terminal support portions (62) formed on each of the pair of leg portions,
The terminal to be connected is fitted to each of the pair of terminal support portions, deforms the curved portion, compresses in the stacking direction (X), and receives a reaction force from the curved portion, thereby receiving the bus bar. A battery pack that is fixedly connected to the battery pack. A plurality of battery cells (10) having a positive electrode terminal and a negative electrode terminal (11) projecting from the outer case (12) are stacked, and the battery cell (10) adjacent to the stacking direction (X) is to be connected. A battery pack (1) configured to connect between terminals using a bus bar (70) and to be energized,
The bus bars are formed on both ends of the battery cell in the stacking direction (X) and are respectively provided on a pair of terminal support portions (71) for supporting the electrode terminals, and on inner peripheral portions of the pair of terminal support portions. A semicircular opening (72) formed and fitted with the electrode terminal, and a connecting portion (73) connecting the pair of terminal support portions; and
The terminal to be connected is fitted into each of the semicircular openings and deformed so as to expand the pair of terminal support portions and pulled in the stacking direction (X) and from the pair of terminal support portions. The battery pack is connected and fixed to the bus bar in response to the reaction force. In the battery pack (1) configured by stacking a plurality of battery cells (10) each having a positive electrode terminal and a negative electrode terminal (11) projecting from the outer case (12), adjacent to the stacking direction (X) A connection method between electrode terminals for connecting the terminals to be connected in the battery cells to be energized using a plurality of bus bars (50),
Each of the bus bars has a first through hole (51) and a second through hole (51A) penetrating in the thickness direction with an inner diameter dimension equal to or less than the outer shape of the terminal of the battery cell. ,
A bus bar arranging step of arranging the bus bar in such a manner that the positive electrode terminal and the negative electrode terminal to be connected to the adjacent battery cells can be press-fitted into the first through hole and the second through hole, respectively.
A press-fitting jig (20) in which a plurality of terminal insertion paths (23) are formed at corresponding positions where the positive electrode terminal and the negative electrode terminal to be connected can be inserted, and the positive electrode terminal and the negative electrode terminal are connected to the terminal. An electrode terminal comprising: a bus bar connecting step of pressing the bus bar and the electrode terminal into a press-fitting manner from the state inserted into the insertion path into the bus bar arranged in the bus bar arranging step. How to connect between.   The method for connecting electrode terminals according to claim 9, wherein the bus bar (50) is made of an elastic body.   The said bus-bar (50) is formed with the slit (52) extended outside from each inner peripheral edge part of said 1st through-hole (51) and said 2nd through-hole (51A), It is characterized by the above-mentioned. Claim | item 9 or the connection method between the electrode terminals of Claim 10.   The method for connecting electrode terminals according to claim 11, wherein the slit extends outward from the inner peripheral edge in a direction (Y) perpendicular to the stacking direction (X) of the battery cells.   One of the first through hole (51) and the second through hole (51A) is formed in a long hole shape in the stacking direction (X) of the battery cells. The connection method between the electrode terminals as described in any one of Claim 12.

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