JP2017010880A - Battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module able to detect fastened states of parts by a simple configuration.SOLUTION: A battery module 1 comprises: a battery cell 10 from which a negative terminal 16 is projected; a bus bar 43 electrically connected to the negative terminal 16; a conductive member 50 including one end 51 and the other end 52 and an intermediate part 53 between the one end 51 and the other end 52, and forming a conductive passage between the negative terminal 16 and bus bar 43 by its being fastened to the negative terminal 16 at the one end 51 and fastened to the bus bar 43 at the other end 52; and a voltage detection terminal 60 fastened to the one end 51 or the other end 52 and configured to detect a fastened state of the negative terminal 16 and the one end 51 and a fastened state of the other end 52 and the bus bar 43.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a battery module.

  Patent Document 1 describes a battery pack management device. The battery pack management device includes a fastening detection unit and a control unit. The battery pack includes a plurality of battery modules and a bus bar. The battery module is provided with electrode terminals. The bus bar is fastened to the electrode terminal of the battery module together with the nut. The fastening sensing unit senses the fastening state of the bus bar. The fastening sensing unit is composed of a pressure sensor.

Special table 2014-507757 gazette

  By the way, in the battery module (battery module) described above, there may be a case where a space around a harness or the like is formed above the position where the electrode terminals of a plurality of battery cells are arranged. In that case, when the bus bar is fastened to the electrode terminal, a conductive member that functions as a spacer may be interposed between the electrode terminal and the bus bar. In this case, a plurality of fastening points may be generated between the electrode terminal and the bus bar, such as fastening of the electrode terminal and the conductive member and fastening of the conductive member and the bus bar. At this time, it is desirable to detect the fastening state of a plurality of fastening locations with a configuration as simple as possible.

  This invention is made | formed in view of such a situation, and it aims at providing the battery module which can detect the fastening state of a several fastening location by simple structure.

  In order to solve the above-described problems, a battery module according to the present invention includes a battery cell having an electrode terminal projecting therefrom, a bus bar electrically connected to the electrode terminal, one end and the other end, and one end. An intermediate portion between the electrode terminal and the other end, and is fastened to the electrode terminal at one end and fastened to the bus bar at the other end, thereby forming a conductive path between the electrode terminal and the bus bar. A member, and a detection terminal that is fastened to one end or the other end and detects a fastening state between the electrode terminal and the one end and a fastening state between the other end and the bus bar.

  The battery module includes a conductive member that forms a conductive path between the electrode terminal and the bus bar by being fastened to both the electrode terminal and the bus bar. The electrode terminal is fastened to one end of the conductive member, and the bus bar is fastened to the other end of the conductive member. Therefore, a space corresponding to the height of the intermediate portion of the conductive member is formed on the electrode terminal. On the other hand, by interposing a conductive member between the electrode terminal and the bus bar, a plurality of (here, fastening of the electrode terminal and one end of the conductive member and fastening of the other end of the conductive member and the bus bar) Then two) fastening points are generated. On the other hand, in this battery module, the detection terminal for detecting the fastening state of each fastening location is fastened to one end or the other end of the conductive member. Thereby, it becomes possible to detect the fastening state of a some fastening location by simple structure.

  In the battery module according to the present invention, the other end portion is formed in a columnar shape, and the intermediate portion is formed in a columnar shape larger than the other end portion, and the one end portion, the other end portion, and the intermediate portion. Are formed integrally with each other, and the other end portion is fastened to the bus bar by screwing a nut in a state where the bus bar is disposed in a stepped portion between the other end portion and the intermediate portion, and the detection terminal is In addition, it may be interposed between the stepped portion and the bus bar. Here, one end portion of the integrally formed conductive member is fastened to the electrode terminal, and the other end portion is fastened to the bus bar by screwing the nut. In this case, if the detection terminal is interposed between the step portion between the other end portion and the intermediate portion of the conductive member and the bus bar, the fastening between the one end portion of the conductive member and the electrode terminal is performed by a single detection terminal. It is possible to detect both the state and the fastening state between the other end of the conductive member and the bus bar. In particular, in this case, the detection terminal is disposed closer to the electrode terminal than the bus bar. For this reason, the wiring of the detection terminal is easy to handle, and the assembling property is not easily lost.

  In the battery module according to the present invention, the other end portion is formed in a columnar shape, and the intermediate portion is formed in a columnar shape larger than the other end portion, and the one end portion, the other end portion, and the intermediate portion. Are formed integrally with each other, and the other end portion is fastened to the bus bar by screwing a nut in a state where the bus bar is disposed in a stepped portion between the other end portion and the intermediate portion, and the detection terminal is In addition, it may be interposed between the bus bar and the nut. Here, one end portion of the integrally formed conductive member is fastened to the electrode terminal, and the other end portion is fastened to the bus bar by screwing the nut. In this case, if a detection terminal is interposed between the bus bar and the nut, the fastening state between the one end of the conductive member and the electrode terminal and the other end of the conductive member and the bus bar are obtained by a single detection terminal. It is possible to detect both of the fastening state. In particular, in this case, the detection terminal is arranged farther from the electrode terminal than the bus bar. For this reason, the detection terminal hardly affects the conductive path between the electrode terminal and the bus bar.

  In the battery module according to the present invention, the electrode terminal may be formed with a first screw hole, and one end may be fastened to the electrode terminal by being screwed into the first screw hole. Alternatively, in the battery module according to the present invention, a second screw hole is formed on one end surface of the conductive member on one end portion side, and an electrode terminal is screwed into the second screw hole on one end portion. It may be fastened to the electrode terminal. As described above, one end of the conductive member may be a male screw or a female screw.

  In the battery module according to the present invention, a second screw hole is formed on one end surface of the conductive member on one end portion side, and a third screw hole is formed on the other end surface on the other end portion side of the conductive member. The one end portion, the other end portion, and the intermediate portion are formed integrally with each other, and the one end portion is fastened to the electrode terminal by screwing the electrode terminal into the second screw hole. The other end is fastened to the bus bar by screwing a bolt into the third screw hole in a state where the bus bar is disposed on the other end surface, and the detection terminal is interposed between the bus bar and the other end surface. It may be. Thus, even when one end and the other end of the conductive member are female screws, if the detection terminal is interposed between the end surface on the other end of the conductive member and the bus bar, With the detection terminal, it is possible to detect both the fastening state between the one end of the conductive member and the electrode terminal and the fastening state between the other end of the conductive member and the bus bar. In particular, in this case, the detection terminal is disposed closer to the electrode terminal than the bus bar. For this reason, the wiring of the detection terminal is easy to handle, and the assembling property is not easily lost.

  In the battery module according to the present invention, a second screw hole is formed on one end surface of the conductive member on one end portion side, and a third screw hole is formed on the other end surface on the other end portion side of the conductive member. The one end portion, the other end portion, and the intermediate portion are formed integrally with each other, and the one end portion is fastened to the electrode terminal by screwing the electrode terminal into the second screw hole. The other end is fastened to the bus bar by screwing the bolt into the third screw hole in a state where the bus bar is disposed on the other end surface, and the detection terminal is interposed between the bus bar and the head of the bolt. It may be interposed. Also in this case, it is possible to detect both the fastening state between the one end portion of the conductive member and the electrode terminal and the fastening state between the other end portion of the conductive member and the bus bar by a single detection terminal. is there. In particular, in this case, the detection terminal is arranged farther from the electrode terminal than the bus bar. For this reason, the detection terminal hardly affects the conductive path between the electrode terminal and the bus bar.

  In the battery module according to the present invention, the conductive member may include a cylindrical member that configures the intermediate portion, and a rod-shaped member that includes one end and the other end and is inserted through the cylindrical member. In this case, the conductive path between the electrode terminal and the bus bar can be formed by the cylindrical member while the fastening between the electrode terminal and the bus bar is realized by the rod-shaped member. That is, while the rod-shaped member is made of a material that can secure the fastening strength, the cylindrical member can be made of a highly conductive material.

  In the battery module according to the present invention, the rod-shaped member is inserted through the tubular member so as to be movable with respect to the tubular member along the extending direction of the rod-shaped member, and the other end portion is the other end portion. In the state where the bus bar is disposed in the stepped portion between the intermediate portion and the intermediate portion, the nut is screwed to be fastened to the busbar, and the detection terminal is formed between the stepped portion between the one end portion and the intermediate portion and the electrode terminal. It may be interposed between them. In this case, if the detection terminal is interposed in the step portion between the one end portion and the intermediate portion of the conductive member, the fastening state between the one end portion of the conductive member and the electrode terminal by a single detection terminal, and It is possible to detect both the fastening state between the other end of the conductive member and the bus bar. In particular, in this case, since the detection terminal is disposed at a position closer to the electrode terminal, the assembling property is hardly impaired.

  In the battery module according to the present invention, the detection terminal may be a voltage detection terminal. In this case, for example, in addition to the detection of the fastening state, it is possible to acquire information on the battery cell characteristics such as voltage.

  ADVANTAGE OF THE INVENTION According to this invention, the battery module which can detect the fastening state of a some fastening location by simple structure can be provided.

It is a perspective view of the battery module concerning this embodiment. It is sectional drawing of the battery module shown by FIG. It is a partial expanded sectional view of the battery module shown by (a) of FIG. FIG. 4 is a partially enlarged cross-sectional view showing a modification of the arrangement of the voltage detection terminals shown in FIG. 3. It is a partially expanded sectional view of the battery module which concerns on a modification. It is a partially expanded sectional view of the battery module which concerns on a modification. It is a perspective view which shows the modification of the electrically-conductive member shown by FIG. It is a partially expanded sectional view of the battery module which concerns on a modification.

  Hereinafter, an embodiment of a battery module according to the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements or corresponding elements may be denoted by the same reference numerals, and redundant descriptions may be omitted.

  FIG. 1 is a perspective view of the battery module according to the present embodiment. FIG. 2 is a cross-sectional view of the battery module shown in FIG. 2A is a cross-sectional view taken along the line IIa-IIa in FIG. FIG. 2B is a partial cross-sectional view taken along the line IIb-IIb in FIG. As shown in FIGS. 1 and 2, the battery module 1 includes a plurality (here, seven) of battery cells 10 stacked along a predetermined direction, and a plurality (here, each) of the battery cells 10. 7) cell holders 20, a restraining member 30 that restrains the battery cells 10 along the stacking direction of the battery cells 10, and a plurality of bus bars 41, 42, 43 connected to the battery cells 10.

  The battery cell 10 is a nonaqueous electrolyte secondary battery such as a lithium ion secondary battery. The battery cell 10 includes a hollow case 12 having a rectangular parallelepiped shape, and an electrode assembly 13 accommodated in the case 12. The case 12 is made of a metal such as aluminum. The case 12 has a top surface 12a and a bottom surface 12b facing each other, side surfaces 12c and 12d facing each other, and side surfaces 12e and 12f facing each other. The side surfaces 12 c and 12 d are surfaces that intersect the stacking direction (predetermined direction) of the battery cells 10. The side surfaces 12 e and 12 f are surfaces along the stacking direction of the battery cells 10.

  For example, an organic solvent-based or non-aqueous electrolyte is injected into the case 12. On the top surface 12 a of the case 12, the positive electrode terminal 15 and the negative electrode terminal 16 are disposed so as to be separated from each other. The positive terminal 15 is fixed to the top surface 12a of the case 12 via an insulating ring (not shown). The negative electrode terminal 16 is fixed to the top surface 12a of the case 12 via an insulating ring (not shown). That is, the battery cell 10 has the electrode terminals (the positive electrode terminal 15 and the negative electrode terminal 16) protruding from the top surface 12 a of the case 12.

  The electrode assembly 13 includes, for example, a positive electrode 13p, a negative electrode 13n, and a bag-like separator (not shown) disposed between the positive electrode 13p and the negative electrode 13n. In the electrode assembly 13, for example, the positive electrodes 13p are accommodated in a separator, and in this state, the positive electrodes 13p and the negative electrodes 13n are alternately stacked via the separators. The positive electrode 13p is connected to the positive electrode terminal 15 via the tab 13t and the current collecting member A. The negative electrode 13n is connected to the negative electrode terminal 16 via the tab 13t and the current collecting member A. Note that the stacking direction of the positive electrode 13p and the negative electrode 13n in the electrode assembly 13 coincides with the stacking direction of the battery cells 10.

  The cell holder 20 includes a pair of side wall portions 20c and 20d and a bottom wall portion 20b that face each other. The side wall portions 20c and 20d have a rectangular plate shape. The bottom wall portion 20b has a rectangular plate shape, and connects the side wall portion 20c and the side wall portion 20d to each other at the longitudinal ends of the side wall portions 20c and 20d. The side wall portions 20c and 20d are respectively disposed on the side surfaces 12c and 12d of the case 12 when the battery cell 10 is held. Similarly, the bottom wall portion 20 b is disposed on the bottom surface 12 b of the case 12. The cell holder 20 is provided with a plurality (four in this case) of through-holes 21 through which bolts 32 of a restraining member 30 described later are inserted.

  The restraining member 30 restrains the battery cell 10 along the stacking direction of the battery cells 10. More specifically, the restraining member 30 includes a pair of end plates 31, a plurality of bolts 32, and a plurality of nuts 33. The end plate 31 is disposed on each of one end and the other end of the stacked body (the stacked body of the battery cells 10) in the stacking direction of the battery cells 10.

  The bolt 32 is inserted into the through hole 21 of the cell holder 20 that holds the battery cell 10 and the through hole provided in the end plate 31. The nut 33 is screwed onto the end of the bolt 32 so that the end plates 31 are fastened to each other. Thereby, a binding load is applied to the battery cell 10 via the end plate 31. Each end plate 31 is provided with an L-shaped fixing member 34. The battery module 1 is fixed to, for example, a battery pack housing or the like via the fixing member 34.

  FIG. 3 is a partially enlarged cross-sectional view of the battery module shown in FIG. 1 to 3, the bus bar 41 electrically connects the positive electrode terminal 15 and the negative electrode terminal 16 of the battery cells 10 adjacent to each other. Thereby, the battery cells 10 are connected in series with each other. That is, in the battery module 1, the battery cells 10 are stacked such that the positive terminals 15 and the negative terminals 16 are alternately arranged along the stacking direction of the battery cells 10.

  The bus bar 42 is electrically connected to the positive terminal 15 (total plus) of the battery cell 10 located at the one end 1 a of the battery module 1. The positive electrode terminal 15 is electrically connected to a positive electrode bus bar (not shown) of a terminal block for connecting the plurality of battery modules 1 in parallel via, for example, a bus bar 42 and a harness (not shown).

  The bus bar 43 is electrically connected to the negative terminal 16 (total minus) of the battery cell 10 located at the other end 1b of the battery module 1. The negative electrode terminal 16 is electrically connected to an electronic component such as a current sensor, an FET relay, or a fuse via, for example, a bus bar 43 or a harness (not shown), and for connecting a plurality of battery modules 1 in parallel. It is electrically connected to a negative electrode bus bar (not shown) of the terminal block.

  The bus bars 42 and 43 are electrically connected to the conductive member 50 and the voltage detection terminal 60. That is, the battery module 1 includes a conductive member 50 and a voltage detection terminal (detection terminal) 60. This point will be described in more detail. Hereinafter, the negative electrode terminal 16 and the bus bar 43 will be mainly described, but the same applies to the positive electrode terminal 15 and the bus bar 42.

  The conductive member 50 includes one end 51 and the other end 52, and an intermediate portion 53 between the one end 51 and the other end 52. The intermediate part 53 connects the one end part 51 and the other end part 52. Here, the one end portion 51, the other end portion 52, and the intermediate portion 53 are integrally formed with each other. The one end 51 and the other end 52 are formed in a cylindrical shape. Screw threads are formed on the outer circumferences of the one end portion 51 and the other end portion 52. That is, here, both ends (one end 51 and the other end 52) of the conductive member 50 are male threads. The intermediate portion 53 is formed in a columnar shape (for example, a hexagonal columnar shape or a cylindrical shape) larger than the one end portion 51 and the other end portion 52.

  When the intermediate portion 53 has a prismatic shape, the distance between the side surfaces facing each other of the intermediate portion 53 is larger than the diameters of the one end portion 51 and the other end portion 52. When the intermediate portion 53 is cylindrical, the diameter of the intermediate portion 53 is larger than the diameters of the one end portion 51 and the other end portion 52. Therefore, a stepped portion 55 is formed between the one end portion 51 and the intermediate portion 53. In addition, a stepped portion 56 is formed between the other end portion 52 and the intermediate portion 53. The step portions 55 and 56 are both end surfaces of the intermediate portion 53, and are portions where the dimensions of the conductive member 50 change along the extending direction of the conductive member 50. The conductive member 50 is, for example, a copper double-ended bolt.

  The one end portion 51 is fastened to the negative electrode terminal 16 by being screwed to the negative electrode terminal 16. More specifically, the negative electrode terminal 16 includes a head portion 16 a located inside the case 12, and a shaft portion 16 b that extends from the head portion 16 a and protrudes from the top surface 12 a of the case 12. The shaft portion 16b is provided with a screw hole (first screw hole) 16h. The one end portion 51 is screwed into the screw hole 16 h so as to enter the screw hole 16 h of the shaft portion 16 b and is fastened to the negative electrode terminal 16. At this time, the step portion 55 abuts on the top portion of the shaft portion 16 b of the negative electrode terminal 16. Note that the stepped portion 55 does not contact the top of the nut N that is screwed in advance with the shaft portion 16b. An insulating member B having a U-shaped cross section is interposed between the case 12 and the negative electrode terminal 16 and between the case 12 and the nut N.

  The other end 52 is fastened to the bus bar 43 when the nut 57 is screwed in a state where the bus bar 43 is disposed in the stepped portion 56. Thereby, the conductive member 50 forms a conductive path between the negative electrode terminal 16 and the bus bar 43. The bus bar 43 is provided with, for example, a cylindrical through hole 43h. Therefore, the bus bar 43 can be disposed on the stepped portion 56 by inserting the other end portion 52 of the conductive member 50 into the through hole 43h.

  The conductive member 50 forms a space corresponding to the height of the intermediate portion 53 between the negative electrode terminal 16 and the bus bar 43. The space formed by the conductive member 50 can be used, for example, for routing wiring from the positive electrode terminal 15 and the negative electrode terminal 16 of each battery cell 10. Further, by securing the cover to the other end portion 52 (stepped portion 56) of the conductive member 50, an area for installing the above-described electronic component or the like is secured on the space formed by the conductive member 50. Is possible.

  The voltage detection terminal 60 is fastened to the other end 52 of the conductive member 50. More specifically, the voltage detection terminal 60 is disposed on the stepped portion 56 so as to be interposed between the stepped portion 56 and the bus bar 43. The voltage detection terminal 60 is fastened to the other end 52 together with the bus bar 43 by screwing the nut 57 to the other end 52. The voltage detection terminal 60 is configured, for example, as a round terminal at a terminal portion of a wiring (not shown) extending from a voltage detection device (for example, the electronic component described above). Therefore, here, the voltage detection terminal 60 is disposed on the stepped portion 56 by being inserted into the other end portion 52.

  As described above, in the battery module 1, in the connection structure between the electrode terminal and the bus bar, the negative electrode terminal 16 is fastened to the one end 51 of the conductive member 50, and the other end 52 of the conductive member 50 is connected to the bus bar. Two fastening points of fastening with 43 are generated. The voltage detection terminal 60 detects the fastening state of these two fastening locations. That is, the voltage detection terminal 60 detects the fastening state between the negative electrode terminal 16 and the one end 51 and the fastening state between the other end 52 and the bus bar 43.

  More specifically, the voltage detection terminal 60 is interposed between the stepped portion 56 and the bus bar 43 and fastened to the other end portion 52 together with the bus bar 43 as described above. The other end portion 52 is formed integrally with the one end portion 51 via the intermediate portion 53. Therefore, in the voltage detection terminal 60, when the fastening between the other end portion 52 of the conductive member 50 and the bus bar 43 is loosened, and the fastening between the one end portion 51 of the conductive member 50 and the negative electrode terminal 16 is loosened. In any case, an increase in voltage on the conductive path from the negative electrode terminal 16 to the bus bar 43 can be detected due to an increase in contact resistance at each fastening point. Therefore, in the battery module 1, the fastening state of both ends of the conductive member 50 can be detected by the single voltage detection terminal 60.

  As described above, the battery module 1 according to this embodiment is fastened to both the negative electrode terminal 16 and the bus bar 43, thereby forming a conductive member 50 that forms a conductive path between the negative electrode terminal 16 and the bus bar 43. It has. The negative terminal 16 is fastened to one end 51 of the conductive member 50, and the bus bar 43 is fastened to the other end 52 of the conductive member 50. Therefore, a space corresponding to the height of the intermediate portion 53 of the conductive member 50 is formed on the negative electrode terminal 16. That is, the conductive member 50 is caused to function as a spacer.

  On the other hand, by interposing the conductive member 50 between the negative electrode terminal 16 and the bus bar 43, the negative electrode terminal 16 and the one end 51 of the conductive member 50 are fastened, and the other end 52 of the conductive member 50 and the bus bar 43 are connected. A plurality of (two in this case) fastening points are generated as shown in FIG. On the other hand, in the battery module 1, the voltage detection terminal 60 for detecting the fastening state of each fastening portion is fastened to the other end 52 of the conductive member 50. Thereby, it becomes possible to detect the fastening state of a some fastening location by simple structure.

  In particular, in the battery module 1 according to the present embodiment, the one end portion 51, the other end portion 52, and the intermediate portion 53 of the conductive member 50 are integrally formed. Further, the one end 51 is fastened to the negative electrode terminal 16 by being screwed to the negative electrode terminal 16. Further, the other end portion 52 is fastened to the bus bar 43 by screwing the nut 57 in a state where the bus bar 43 is disposed in the step portion 56 between the other end portion 52 and the intermediate portion 53.

  The voltage detection terminal 60 is interposed between the step portion 56 and the bus bar 43, and is fastened to the other end portion 52 together with the bus bar 43. For this reason, both the fastening state between the one end portion 51 of the conductive member 50 and the negative electrode terminal 16 and the fastening state between the other end portion 52 of the conductive member 50 and the bus bar 43 are provided by the single voltage detection terminal 60. It is possible to detect. In particular, in this case, the voltage detection terminal 60 is disposed closer to the negative electrode terminal 16 than the bus bar 43. For this reason, the wiring of the voltage detection terminal 60 is easy to handle, and the assembling property is not easily impaired.

  Furthermore, in the battery module 1 according to the present embodiment, the voltage detection terminal 60 is used as a detection terminal for detecting the fastening state. For this reason, in addition to the detection of a fastening state, it is possible to acquire information regarding the characteristics of the battery cell 10 such as a voltage.

  The above embodiment describes one embodiment of the battery module according to the present invention. Therefore, the battery module according to the present invention is not limited to the battery module 1 described above. In the battery module according to the present invention, the above-described battery module 1 can be arbitrarily changed without changing the gist of each claim.

  FIG. 4 is a partially enlarged cross-sectional view showing a modified example of the arrangement of the voltage detection terminals shown in FIG. As shown in FIG. 4, the voltage detection terminal 60 may be interposed between the bus bar 43 and the nut 57. Thus, even if the voltage detection terminal 60 is interposed between the bus bar 43 and the nut 57, for the same reason as described above, the one end 51 of the conductive member 50 and the negative electrode are separated by the single voltage detection terminal 60. It is possible to detect both the fastening state between the terminal 16 and the fastening state between the other end portion 52 of the conductive member 50 and the bus bar 43. In particular, in this case, the voltage detection terminal 60 is arranged farther from the negative electrode terminal 16 than the bus bar 43. For this reason, the voltage detection terminal 60 hardly affects the conductive path between the negative electrode terminal 16 and the bus bar 43.

  Further, the battery module 1 may be a battery module 1A including the conductive member 50A shown in FIG. The conductive member 50 </ b> A includes one end 51 and the other end 52, and an intermediate portion 53 between the one end 51 and the other end 52. The intermediate part 53 connects the one end part 51 and the other end part 52. Here, the one end portion 51, the other end portion 52, and the intermediate portion 53 are integrally formed with each other. As an example, here, the one end portion 51, the other end portion 52, and the intermediate portion 53 have substantially the same outer shape. Therefore, here, no stepped portion is formed between the one end portion 51 and the other end portion 52 and the intermediate portion 53. As a whole, the conductive member 50A is formed in a column shape such as a hexagonal column.

  The one end portion 51 is fastened to the negative electrode terminal 16 by being screwed to the negative electrode terminal 16. More specifically, a screw hole (second screw hole) 51h is formed in the end surface (one end surface) 51s on the one end 51 side of the conductive member 50A. Further, a screw thread is formed on the outer periphery of the shaft portion 16 b of the negative electrode terminal 16. The one end portion 51 is fastened to the negative electrode terminal 16 by screwing the negative electrode terminal 16 into the screw hole 51h so that the shaft portion 16b of the negative electrode terminal 16 enters the screw hole 51h.

  On the other hand, a screw hole (third screw hole) 52h is formed in the end surface (other end surface) 52s on the other end 52 side of the conductive member 50A. Therefore, here, both ends (one end 51 and the other end 52) of the conductive member 50A are female screws. The other end 52 is fastened to the bus bar 43 by screwing a bolt 57A into the screw hole 52h in a state where the bus bar 43 is disposed on the end surface 52s. Thereby, the conductive member 50 </ b> A forms a conductive path between the negative electrode terminal 16 and the bus bar 43. The shaft portion 57b of the bolt 57A is inserted through the through hole 43h of the bus bar 43 disposed on the end surface 52s and enters the screw hole 52h. Accordingly, the other end 52 is fastened to the bus bar 43 so that the bus bar 43 is sandwiched between the head 57a of the bolt 57A and the end surface 52s.

  The voltage detection terminal 60 is interposed between the bus bar 43 and the end surface 52 s and is fastened to the other end 52. More specifically, the voltage detection terminal 60 is disposed on the end surface 52s so as to be interposed between the bus bar 43 and the end surface 52s. The voltage detection terminal 60 is fastened to the other end 52 together with the bus bar 43 by screwing the bolt 57A to the other end 52.

  Even when the one end 51 and the other end 52 of the conductive member 50A are female screws as in the battery module 1A described above, the gap between the end face 52s on the other end 52 side of the conductive member 50A and the bus bar 43 is between. If the voltage detection terminal 60 is interposed between the one end 51 and the negative terminal 16 of the conductive member 50A, and the other end 52 and the bus bar of the conductive member 50A. It is possible to detect both the fastening state with 43. In particular, since the voltage detection terminal 60 is disposed closer to the negative electrode terminal 16 than the bus bar 43, the wiring of the voltage detection terminal 60 can be easily routed, and the assembling property is not easily impaired.

  Here, the battery module 1 can be a battery module 1B including the conductive member 50B shown in FIG. In the conductive member 50 </ b> B, one end 51 is a female screw similarly to the conductive member 50 </ b> A, and the other end 52 is a male screw similar to the conductive member 50. More specifically, a screw hole 51h is formed in the end surface 51s on the one end 51 side of the conductive member 50B. The one end portion 51 is fastened to the negative electrode terminal 16 by screwing the negative electrode terminal 16 into the screw hole 51h so that the shaft portion 16b of the negative electrode terminal 16 enters the screw hole 51h.

  On the other hand, in the conductive member 50 </ b> B, the other end portion 52 is formed in a columnar shape smaller than the intermediate portion 53. A thread is formed on the outer periphery of the other end 52. The other end 52 is fastened to the bus bar 43 when the nut 57 is screwed in a state where the bus bar 43 is disposed in the stepped portion 56. Thereby, the conductive member 50 </ b> B forms a conductive path between the negative electrode terminal 16 and the bus bar 43. The voltage detection terminal 60 is fastened to the other end 52 of the conductive member 50B. More specifically, the voltage detection terminal 60 is disposed on the stepped portion 56 so as to be interposed between the stepped portion 56 and the bus bar 43. The voltage detection terminal 60 is fastened to the other end 52 together with the bus bar 43 by screwing the nut 57 to the other end 52.

  As in the battery module 1B described above, even if the one end 51 of the conductive member 50B is a female screw and the other end 52 is a male screw, the end face 52s on the other end 52 side of the conductive member 50B and the bus bar. If the voltage detection terminal 60 is interposed between the first and second terminals 43, the single voltage detection terminal 60 can be used to connect the one end 51 of the conductive member 50B to the negative terminal 16 and the other end of the conductive member 50B. It is possible to detect both the fastening state of the part 52 and the bus bar 43. In particular, since the voltage detection terminal 60 is disposed closer to the negative electrode terminal 16 than the bus bar 43, the wiring of the voltage detection terminal 60 can be easily routed, and the assembling property is not easily impaired.

  In the battery modules 1A and 1B, the voltage detection terminal 60 may be interposed between the bus bar 43 and the nut 57 (or the head 57a of the bolt 57A) as in the modification shown in FIG. . In this case, the voltage detection terminal 60 is arranged farther from the negative electrode terminal 16 than the bus bar 43. For this reason, the voltage detection terminal 60 hardly affects the conductive path between the negative electrode terminal 16 and the bus bar 43.

  Further, in the battery module 1, the one end portion 51 of the conductive member 50 may be a male screw, and the other end portion 52 of the conductive member 50 may be a female screw similarly to the conductive member 50A.

  Here, the battery module 1 may be a battery module 1C including the conductive member 50C shown in FIGS. 7 and 8 instead of the conductive member 50. The conductive member 50 </ b> C is configured by combining a cylindrical rod-shaped member 58 and a cylindrical member 59. The rod-shaped member 58 has a long shape, and constitutes one end 51 and the other end 52 at each end in the longitudinal direction. That is, the rod-shaped member 58 includes one end 51 and the other end 52 each having a thread formed on the outer periphery, and a connecting portion 51 c that connects the one end 51 and the other end 52. As an example, the connecting portion 51c is not provided with a thread.

  As an example, the cylindrical member 59 has a cylindrical shape obtained by forming a cylindrical through hole 53h in a hexagonal column. The cylindrical member 59 constitutes an intermediate portion 53 formed in a columnar shape larger than the rod-shaped member 58 (one end portion 51, the other end portion 52, and the connection portion 41c). That is, the interval between the mutually opposing side surfaces of the cylindrical member 59 is larger than the diameter of the rod-shaped member 58. The conductive member 50 </ b> A is configured by inserting the rod-shaped member 58 through the through hole 53 h of the cylindrical member 59. Here, the inner diameter of the through hole 53 h is larger than the outer diameter of the rod-shaped member 58. Therefore, the rod-shaped member 58 is inserted through the through hole 53 h of the tubular member 59 so as to be movable with respect to the tubular member 59 along the extending direction of the rod-shaped member 58.

  Here, similarly to the conductive member 50, the conductive member 50 </ b> C has one end 51 fastened to the negative terminal 16 and the other end 52 fastened to the bus bar 43. However, the voltage detection terminal 60 is interposed between the step portion 55 and the negative electrode terminal 16 in the conductive member 50C. More specifically, the voltage detection terminal 60 is interposed between the top portion of the shaft portion 16 b of the negative electrode terminal 16 and the step portion 55.

  In this case, the voltage detection terminal 60 increases the contact resistance between the stepped portion 55 and the negative electrode terminal 16 when the fastening between the one end portion 51 of the conductive member 50C (rod-shaped member 58) and the negative electrode terminal 16 is loosened. It is possible to detect a rise in voltage due to. Further, in this case, for example, when the screw 57 is loosely engaged with the other end 52 and loosening occurs between the bus bar 43 and the other end 52, the loosening causes the negative electrode of the step 55. The pressing force on the terminal 16 is reduced. Therefore, in this case as well, the voltage detection terminal 60 can detect an increase in voltage due to an increase in contact resistance between the step portion 55 and the negative electrode terminal 16.

  That is, also in the battery module 1 </ b> C, a single voltage detection terminal 60 is used to connect the one end portion 51 of the conductive member 50 </ b> C to the negative electrode terminal 16 and the other end portion 52 of the conductive member 50 </ b> C and the bus bar 43. It is possible to detect both fastening states. In particular, in this case, since the voltage detection terminal 60 is disposed at a position closer to the negative electrode terminal 16, the assemblability is hardly impaired.

  Further, in the battery module 1C, the rod-shaped member 58 of the conductive member 50C realizes fastening between the negative electrode terminal 16 and the bus bar 43, while the negative electrode terminal 16 and the bus bar 43 are connected by the cylindrical member 59 of the conductive member 50C. A conductive path between the two can be formed. That is, while the rod-shaped member 58 is made of a material (for example, iron) that can secure the fastening strength, the cylindrical member 59 can be made of a highly conductive material (for example, copper).

  In the battery module 1C, the position where the voltage detection terminal 60 is interposed may be changed. That is, also in the battery module 1 </ b> C, the voltage detection terminal 60 may be interposed between the stepped portion 56 and the bus bar 43 or between the bus bar 43 and the nut 57.

  Further, as described above, the above configuration can be similarly applied between the positive electrode terminal 15 and the bus bar 42. Further, the above configuration may be similarly applied between the positive electrode terminal 15 and the negative electrode terminal 16 and the bus bar 41 of the other battery cell 10 located inside the battery modules 1 to 1C. Furthermore, in the battery modules 1 to 1C, instead of the voltage detection terminal 60, another detection terminal capable of detecting the fastening state such as a pressure sensor can be used.

  DESCRIPTION OF SYMBOLS 1,1A, 1B, 1C ... Battery module, 10 ... Battery cell, 15 ... Positive electrode terminal (electrode terminal), 16 ... Negative electrode terminal (electrode terminal), 41, 42, 43 ... Bus bar, 50, 50A, 50B, 50C ... Conductive member, 51 ... one end, 51h ... screw hole (second screw hole), 51s ... end face (one end face), 52 ... other end, 52h ... screw hole (third screw hole), 52s ... end face ( Other end surface), 53 ... Intermediate part, 55, 56 ... Step part, 57 ... Nut, 57A ... Bolt, 57a ... Head, 58 ... Bar-like member, 59 ... Cylindrical member, 60 ... Voltage detection terminal (detection terminal).

Claims (10)

A battery cell with protruding electrode terminals;
A bus bar electrically connected to the electrode terminal;
One end portion and the other end portion, and an intermediate portion between the one end portion and the other end portion, and fastened to the electrode terminal at the one end portion and fastened to the bus bar at the other end portion. A conductive member that forms a conductive path between the electrode terminal and the bus bar;
Fastened to the one end or the other end, a fastening state between the electrode terminal and the one end, and a detection terminal for detecting a fastening state between the other end and the bus bar,
A battery module comprising: The other end is formed in a columnar shape,
The intermediate part is formed in a larger column shape than the other end part,
The one end portion, the other end portion, and the intermediate portion are integrally formed with each other,
The other end portion is fastened to the bus bar by screwing a nut in a state where the bus bar is disposed in a step portion between the other end portion and the intermediate portion,
The detection terminal is interposed between the stepped portion and the bus bar;
The battery module according to claim 1. The other end is formed in a columnar shape,
The intermediate part is formed in a larger column shape than the other end part,
The one end portion, the other end portion, and the intermediate portion are integrally formed with each other,
The other end portion is fastened to the bus bar by screwing a nut in a state where the bus bar is disposed in a step portion between the other end portion and the intermediate portion,
The detection terminal is interposed between the bus bar and the nut;
The battery module according to claim 1. A first screw hole is formed in the electrode terminal,
The one end is fastened to the electrode terminal by being screwed into the first screw hole.
The battery module according to claim 2 or 3. A second screw hole is formed on one end surface of the one end side of the conductive member,
The one end is fastened to the electrode terminal by screwing the electrode terminal into the second screw hole.
The battery module according to claim 2 or 3. A second screw hole is formed on one end surface of the one end side of the conductive member,
A third screw hole is formed on the other end surface of the conductive member on the other end side,
The one end portion, the other end portion, and the intermediate portion are integrally formed with each other,
The one end is fastened to the electrode terminal by screwing the electrode terminal into the second screw hole,
The other end is fastened to the bus bar by screwing a bolt into the third screw hole in a state where the bus bar is disposed on the other end surface,
The detection terminal is interposed between the bus bar and the other end surface,
The battery module according to claim 1. A second screw hole is formed on one end surface of the one end side of the conductive member,
A third screw hole is formed on the other end surface of the conductive member on the other end side,
The one end portion, the other end portion, and the intermediate portion are integrally formed with each other,
The one end is fastened to the electrode terminal by screwing the electrode terminal into the second screw hole,
The other end is fastened to the bus bar by screwing a bolt into the third screw hole in a state where the bus bar is disposed on the other end surface,
The detection terminal is interposed between the bus bar and the head of the bolt,
The battery module according to claim 1. The conductive member includes a cylindrical member that constitutes the intermediate portion, and a rod-like member that constitutes the one end portion and the other end portion and is inserted through the cylindrical member.
The battery module according to claim 1. The rod-shaped member is inserted through the tubular member so as to be movable with respect to the tubular member along the extending direction of the rod-shaped member,
The other end portion is fastened to the bus bar by screwing a nut in a state where the bus bar is disposed in a step portion between the other end portion and the intermediate portion,
The detection terminal is interposed between the step portion between the one end portion and the intermediate portion and the electrode terminal.
The battery module according to claim 8. The detection terminal is a voltage detection terminal.
The battery module as described in any one of Claims 1-9.

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