Battery module

Abstract

A battery module (1) comprises: a battery body (10) in which battery cells (11) provided with tabs (12) on the X side are laminated; a connection terminal (40) to which the tabs (12) are electrically connected; a circuit board (20) which supports the connection terminal (40); and a case (2) which accommodates the battery body (10) and the circuit board (20), and has an insertion hole (30) into which the connection terminal (40) is inserted and comes out of. The connection terminal (40) has a fastening shaft (43) parallel to the X direction and comprises a terminal body portion (41) of which a cross-section orthogonal to the X direction is non-circular. The shape of the insertion hole (30) orthogonal to the X direction is formed to be the same shape as the terminal body portion (41).

Description

Battery module

[0001] The present invention relates to a battery module.

[0002] In a conventional electronic control device in which a circuit board is housed in a case and connection terminals provided on the circuit board protrude outside the case, an external connection member is engaged with the connection terminal and fastened with an external fastening member (see, for example, Patent Document 1). In Patent Document 1, the circuit board and the connection terminal are fastened with the circuit board fastening member, and the axis of the external fastening member and the axis of the circuit board fastening member are offset so as not to be coaxial, so that the connection terminal does not rotate even when torque is applied to the external fastening member.

[0003] JP 2014-193071 A

[0004] In a battery module including a battery main body and a case for housing the battery main body, wiring connected to the battery main body may be connected to connection terminals inserted inside and outside the case, and a conductive member such as a bus bar may be fastened to the connection terminals protruding outside the case. When a configuration such as that described in Patent Document 1 is used to fasten the bus bar to the connection terminal, torque input from the external fastening member is directly input from the connection terminal to a support member (e.g., a circuit board or a support board) provided inside the case that supports the connection terminal. This applies a load to the support member, which may be damaged.

[0005] An object of the present invention is to provide a battery module that can suppress the load on the support member even when fastening members are fastened to the connection terminals.

[0006] A battery module according to one aspect of the present invention includes a case that houses a battery main body and a support member that supports a connection terminal, and the case is provided with an insertion hole through which the connection terminal is inserted. The connection terminal has a fastening axis that is parallel to the insertion direction of the insertion hole and includes a terminal body portion whose cross section perpendicular to the insertion direction is non-circular. The insertion hole of the case has a shape perpendicular to the insertion direction that is the same as the shape of the terminal body portion.

[0007] As a result, when the connection terminal is inserted into the insertion hole of the case, even if a rotational torque around the fastening axis is applied to the connection terminal by the fastening member, the non-circular terminal body fits into the insertion hole and the rotational torque can be released to the case, thereby suppressing transmission of the rotational torque to the support member that holds the connection terminal and preventing damage to the support member.

[0008] FIG. 1 is an overall view showing a schematic configuration of a battery module of a first embodiment; FIG. 2 is an exploded perspective view showing a portion of the battery module of FIG. 1 disassembled; FIG. 3 is a plan view showing a schematic configuration of a circuit board of the present embodiment; FIG. 4 is a cross-sectional view of the circuit board cut along line A-A in FIG. 3; FIG. 5 is a perspective view showing a configuration of a connection terminal of the present embodiment; FIG. 6 is a diagram showing distribution of torque transmitted from the connection terminal in the circuit board of the present embodiment; FIG. 7 is a diagram showing an example of a cross-sectional shape of a terminal body of a connection terminal according to Modification 1; FIG. 8 is a diagram showing another example of a cross-sectional shape of a terminal body of a connection terminal according to Modification 1.

[0009] [First Embodiment] A battery module according to a first embodiment of the present invention will be described. FIG. 1 is an overall view showing a schematic configuration of a battery module 1 according to this embodiment. FIG. 2 is an exploded perspective view of a portion of the battery module 1. The battery module 1 includes a case 2, a battery main body 10 (see FIG. 2), and a circuit board 20 (see FIG. 2). In the battery module 1, the battery main body 10 and the circuit board 20 are housed inside the case 2. Furthermore, the battery module 1 according to this embodiment is connected to a separately provided master controller 3 via a wireless communication unit incorporated in the circuit board 20 so as to be able to communicate wirelessly.

[0010] (Configuration of Case 2) As shown in Fig. 2, the case 2 includes an upper plate 2A disposed on the +Y side of the battery main body 10, a lower plate 2B disposed on the -Y side of the battery main body 10, end plates 2C disposed on the ±Z sides of the battery main body 10, and side plates 2D disposed on the ±X sides of the battery main body 10 via a circuit board 20. The joining of the upper plate 2A and the end plates 2C and the joining of the lower plate 2B and the end plates 2C are not particularly limited, and examples include joining using fastening members such as screws, joining using an adhesive, welding, etc. The side plates 2D are arranged to cover the circuit board 20 after joining tabs 12 extending from the battery main body 10 to the circuit board 20, and are joined to the upper plate 2A, the lower plate 2B, and the end plates 2C.

[0011] In this embodiment, the side plates 2D arranged on the ±X sides of the battery main body 10 each have an insertion hole 30 penetrating in the X direction and through which a terminal barrel 41 of a connection terminal 40 provided on the circuit board 20 is inserted. The insertion hole 30 has a non-circular shape when viewed from the X direction. More specifically, the insertion hole 30 in this embodiment has a substantially D-shape (a shape formed by an arc and a chord) with a portion of a circle cut out. An insulating ring 31 communicating with the insertion hole 30 is arranged on the surface of the side plate 2D opposite the battery main body 10. The inner periphery of the insulating ring 31 has the same shape as the insertion hole 30, i.e., a substantially D-shape. In this embodiment, the connection terminal 40 fixed to the circuit board 20 accommodated in the case 2 is inserted through the insertion hole 30 and the insulating ring 31 and protrudes outside the case 2. A fastening shaft 43 is provided at the tip of the connection terminal 40. A conductive coupling bus bar 50 is engaged with the fastening shaft 43 , and a fastening member 60 such as a nut is fastened to the fastening shaft 43 , thereby fixing the coupling bus bar 50 to the connection terminal 40 .

[0012] (Configuration of Battery Main Body 10) As shown in FIG. 2 , the battery main body 10 is composed of multiple battery cells 11 stacked in the Z direction (second direction in the present disclosure). While detailed illustration of the battery cells 11 is omitted, the battery cells 11 are stacked together, including a positive electrode collector, a positive electrode layer, an electrolyte layer, a negative electrode layer, and a negative electrode collector, and are configured by laminating them together with a laminate film, for example. Each battery cell 11 includes a tab 12 extending in the X direction (first direction in the present disclosure), for example. Power is input and output to and from the battery cell 11 via the tab 12. As shown in FIG. 2 , these tabs 12 are formed in the shape of a flat thin plate extending in the XY direction and extend in the X direction. In this embodiment, the ±X sides are exemplified as the extension directions of the tabs 12 extending from the battery cells 11. In this case, for example, a configuration in which the positive electrode tab extends to the +X side and the negative electrode tab extends to the −X side can be exemplified. On the other hand, the direction in which the tabs 12 are pulled out is not limited to this, and both the positive and negative electrode tabs may be pulled out on the +X side. Alternatively, the positive electrode tab may be pulled out on the +X side and the negative electrode tab may be pulled out on the +Y side. In this case, circuit boards 20 are provided on the +X side and +Y side of the battery main body 10, which are the pulling directions of the tabs 12.

[0013] (Configuration of Circuit Board 20) FIG. 3 is a plan view showing a schematic configuration of the circuit board 20. FIG. 4 is a cross-sectional view of the circuit board 20 cut along line A-A in FIG. 3. While the circuit board 20 arranged on the +X side of the battery main body 10 is described here as an example, the same applies to a circuit board 20 arranged on the -X side of the battery main body 10. The circuit board 20 is formed in a substantially rectangular shape when viewed from the X direction, and four rectangular corners 201, 201 of the rectangle are positioned and fixed to the case 2. Specifically, the circuit board 20 includes a first engagement piece 20A provided at a first rectangular corner 201 on the -X+Y side and a second engagement piece 20B provided at a second rectangular corner 202. Each engagement piece 20A, 20B protrudes in the Z direction and engages with an engagement hole 2E formed in the opposing end plate 2C. The first engagement piece 20A is formed to have a greater length along the Y direction than the second engagement piece 20B. That is, the cross-sectional area of ​​the XY cross section of the first engagement piece 20A is larger than the cross-sectional area of ​​the XY cross section of the second engagement piece 20B. After joining the tab 12, the circuit board 20 is fixed by engaging the first engagement piece 20A and the second engagement piece 20B with the engagement hole 2E of the end plate 2C and joining the side plate 2D to the upper plate 2A, the lower plate 2B, and the end plate 2C.

[0014] The circuit board 20 includes a substrate 21 on which a circuit pattern 215 is formed, and a plurality of openings 22 are formed in the substrate 21. As shown in Fig. 3, the openings 22 are formed longitudinally in the Y direction. These openings 22 are provided at positions facing the tabs 12 of the battery main body 10, respectively.

[0015] A plurality of bus bars 23 are arranged on the base material 21 of the circuit board 20. As shown in FIG. 3 , each bus bar 23 is formed longitudinally in the Y direction, and a portion of an end face parallel to the Y direction faces the opening 22. The side of the bus bar 23 facing the opening 22 is hereinafter referred to as a first opening side surface 231. The ±Y side ends of the bus bar 23 are embedded in the base material 21, thereby fixing the bus bar 23 to the base material 21. The first opening side surface 231 of the bus bar 23 has a groove 232 longitudinal in the Y direction along the opening 22, extending from the surface opposite the battery main body 10 (the surface on the +X side in the drawing).

[0016] The second opening side surface 211, which faces the first opening side surface 231 of the opening 22, is formed of the base material 21. A fixing member 24 that is elongated in the Y direction is disposed on the base material 21 along the second opening side surface 211. In this embodiment, the fixing member 24 is a biasing member that biases the tab 12 inserted into the opening 22 toward the bus bar 23, and more specifically, is formed of a leaf spring.

[0017] As shown in FIG. 4 , the fixing member 24 of this embodiment includes a base end 241 extending from the circuit board 20 toward the −X side (toward the battery main body 10), an extension portion 242 extending from the tip side of the base end 241 toward the first opening side surface 231 of the opening 22, and a tip end 243 extending from the tip side of the extension portion 242 to the side opposite the first opening side surface 231. The base end 241 includes a plate-shaped insertion piece 241A protruding toward the +X side at the +X side end. Furthermore, an insertion hole 212 is formed in the base material 21 of the circuit board 20 along the second opening side surface 211 of the opening 22. The fixing member 24 is fixed to the circuit board 20 by inserting the insertion piece 241A into the insertion hole 212.

[0018] The extension portion 242 is curved and folded back from the tip side of the base end portion 241 toward the first opening side surface 231. The tip portion of the extension portion 242 is bent away from the first opening side surface 231 as it moves toward the +X side, forming a tip portion 243. In this embodiment, the tab 12 is positioned by being sandwiched between a bent corner 244 between the extension portion 242 and the tip portion 243 and the first opening side surface 231 of the bus bar 23, and the groove portion 232 is filled with a conductive brazing material, thereby joining the tab 12 and the bus bar 23 in an electrically conductive state.

[0019] The circuit board 20 of this embodiment also functions as a support member of the present disclosure, and the connection terminal 40 is fixed thereto. Fig. 5 is a perspective view showing a detailed configuration of the connection terminal 40 of this embodiment. The connection terminal 40 of this embodiment is made of a conductive metal material or the like, and as shown in Fig. 5, includes a terminal body 41, a connection protrusion 42 protruding from the terminal body 41 toward the circuit board 20, and a fastening shaft 43 protruding from the terminal body 41 in a direction away from the circuit board 20. The connection terminal 40 is formed in a columnar shape with its center axis parallel to the X direction.

[0020] The cross section of the terminal body 41 perpendicular to the X direction is formed in a non-circular shape. In the present embodiment, the cross section of the terminal body 41 is formed in a substantially D-shape by cutting out a part of a circle, and has the same shape as the inner peripheral shapes of the insertion hole 30 and the insulating ring 31 of the side plate 2D described above. As a result, when the circuit board 20 is accommodated in the case 2 and the side plate 2D is joined to the upper plate 2A, the lower plate 2B, and the end plate 2C, the terminal body 41 is inserted into the insertion hole 30 and the insulating ring 31, and the outer peripheral surfaces of the terminal body 41 abut against the inner peripheral sides of the insertion hole 30 and the insulating ring 31.

[0021] The connection terminals 40 are fixed to the circuit board 20 while being fixed to a terminal bus bar 44. The terminal bus bar 44 is embedded in the circuit board 20, for example, and is connected in series or parallel to the tabs 12 of each battery cell 11 on the circuit board 20. A fitting hole 441 having the same shape as the connection protrusion 42 of the connection terminal 40 is provided in a part of the terminal bus bar 44, and the connection protrusion 42 is crimped into the fitting hole 441, thereby fixing the connection terminal 40 to the terminal bus bar 44. Note that the method of fixing the connection terminals 40 to the terminal bus bar 44 is not limited to crimping, and any fixing method that fixes the connection terminals 40 in an electrically conductive state may be used.

[0022] The fastening shaft 43 of the connection terminal 40 protrudes from the terminal body 41 in the direction away from the circuit board 20 (X direction) and is exposed to the outside of the case 2. As described above, the coupling bus bar 50 engages with the fastening shaft 43 and is fastened with the fastening member 60, thereby fixing the coupling bus bar 50 to the connection terminal 40. This electrically connects the coupling bus bar 50 to the circuit board 20 via the connection terminal 40. In this embodiment, the terminal body 41 is inserted into the insertion hole 30 and the insulating ring 31 of the case 2, and the outer peripheral side surface of the terminal body 41 and the inner peripheral surfaces of the insertion hole 30 and the insulating ring 31 are formed in the same non-circular shape and abut against each other. Therefore, even if a fastening torque is applied to the fastening shaft 43 by the fastening member 60, the connection terminal 40 does not rotate. Furthermore, the fastening torque generated by the fastening member 60 is distributed from the terminal body 41 to the case 2 via the insertion hole 30 and the insulating ring 31. Therefore, the transmission of torque from the connection terminal 40 to the circuit board 20 is suppressed.

[0023] Returning to FIG. 3 , other components of the circuit board 20 of this embodiment will be described. The circuit board 20 of this embodiment has a plurality of electronic chips 213 and a wireless communication chip 214 disposed on the substrate 21. The electronic chips 213 are IC chips that constitute a battery monitoring system, and examples thereof include a temperature measurement chip 213A (temperature measurement unit) for measuring the temperature of each battery cell 11 and a voltage adjustment chip 213B (voltage adjustment unit) for controlling and managing the charge / discharge rate of each battery cell 11. Other electronic chips may also be provided as battery components, such as a state-of-charge measurement chip for measuring the state of charge of the battery main body 10 and a control chip for controlling the operation of the plurality of electronic chips. These electronic chips 213 are connected to the bus bars 23 via, for example, circuit patterns 215 formed on the substrate 21.

[0024] In this embodiment, a wireless communication chip 214 is disposed on the base material 21 of the circuit board 20. The wireless communication chip 214 is connected to, for example, the electronic chips 213, and transmits information obtained by each electronic chip 213 to the master controller 3 via wireless communication. The wireless communication chip 214 may also receive a predetermined command signal from the master controller 3 and output the command signal to each electronic chip 213. Examples of such command signals include command values ​​for starting and ending charging and discharging of the battery cells 11, and the amount of charging and discharging.

[0025] 3 , in this embodiment, the connection terminal 40 is provided near the first rectangular corner 201 on the −X+Y side of the circuit board 20. Meanwhile, the electronic chip 213 and the wireless communication chip 214 are each disposed between the first rectangular corner 201 and the second rectangular corner 202 of the circuit board 20.

[0026] As described above, by configuring the connection terminals 40 to be fixed near the first rectangular corners 201 and the electronic chip 213 and the wireless communication chip 214 to be disposed between the first rectangular corners 201 and the second rectangular corners 202, it is possible to prevent damage to the electronic chip 213 and the wireless communication chip 214. In other words, even if part of the torque of the fastening members 60 is input to the circuit board 20, the torque is concentrated near the first rectangular corners 201 to which the connection terminals 40 are fixed, thereby preventing the load on the electronic chip 213 and the wireless communication chip 214.

[0027] FIG. 6 is a diagram illustrating the distribution of torque transmitted from the connection terminals 40 in the circuit board 20 of this embodiment. Even when fastening torque is input from the connection terminals 40 to the circuit board 20, as shown in FIG. 6 , the torque can be released to the case 2 through the engagement pieces 20A and 20B provided at the four rectangular corners 201 and 202 of the circuit board 20, and the load can be distributed by each engagement piece 20A and 20B. This prevents damage to the circuit board 20, rotation of the circuit board 20, and poor connection of the tabs 12. Furthermore, the first engagement piece 20A located at the first rectangular corner 201 of the circuit board 20 has a larger cross-sectional area than the second engagement piece 20B located at the other rectangular corner 202. With this configuration, a larger input torque can be released to the case 2 from the first engagement piece 20A, which has a larger cross-sectional area. This further reduces the load on the areas where the electronic chip 213 and the wireless communication chip 214 are located.

[0028] [Effects of the Present Embodiment] The battery module 1 of the present embodiment includes a battery main body 10, connection terminals 40 to which tabs are electrically connected, a circuit board 20 serving as a support member for supporting the connection terminals 40, and a case 2 that houses the battery main body 10 and the circuit board 20. The case 2 is provided with insertion holes 30 through which the connection terminals 40 are inserted. The connection terminals 40 include fastening shafts 43 parallel to the X direction and terminal barrels 41 having a noncircular cross section perpendicular to the X direction. The insertion holes 30 have a noncircular shape perpendicular to the X direction that is the same as the shape of the terminal barrels 41. As a result, even if fastening torque is applied when fastening members 60 are fastened to the fastening shafts 43 of the connection terminals 40, the torque can be dispersed from the insertion holes 30 to the insulating ring 31 and the case. This reduces torque on the circuit board 20, thereby preventing damage and rotation of the circuit board 20.

[0029] In the battery module 1 of this embodiment, multiple battery cells 11 are stacked in the Z direction, and tabs 12 extending from each battery cell 11 are connected to a circuit board 20 arranged in the X direction of the battery main body 10. In this battery module 1, it is possible to incorporate a circuit board 20 on which multiple electronic chips 213 functioning as a battery monitoring system are arranged. This allows the battery module 1 to be more compact than a configuration in which the battery main body and a circuit board having a battery monitoring system are connected by wire. Furthermore, in a battery module 1 incorporating such a circuit board 20, it is necessary to protect the circuit board 20 and the electronic chips 213 on the circuit board 20 from the fastening torque input from the connection terminals 40. In contrast, in this embodiment, as described above, the terminal body 41 of the connection terminal 40 is noncircular, and is inserted into the noncircular insertion hole 30 provided in the case 2, thereby dispersing the fastening torque and protecting the circuit board 20 and the electronic chips 213.

[0030] In this embodiment, the circuit board 20 has a rectangular shape when viewed from the X direction, and has engaging pieces 20A and 20B provided at four locations on the rectangular corners 201 and 202. These engaging pieces 20A and 20B are positioned and fixed by engaging with engaging holes 2E provided on the case 2. As a result, even if torque is input to the circuit board 20 from the connection terminals 40, the torque can be dispersed to the case from the engaging pieces 20A and 20B provided on the rectangular corners 201 and 202 of the circuit board 20.

[0031] Furthermore, in this embodiment, the connection terminal 40 is disposed near the first rectangular corner 201 of the four rectangular corners 201, 202. The electronic chip 213 provided on the circuit board 20 is disposed between the first rectangular corner 201 and the second rectangular corner 202. As a result, the fastening torque input from the connection terminal 40 is concentrated on the first rectangular corner 201 of the circuit board 20, which makes it possible to suppress the input of torque to the portion where the electronic chip 213 is disposed, and to suppress damage to the electronic chip 213.

[0032] Furthermore, in this embodiment, the first engagement piece 20A provided at the first rectangular corner 201 of the circuit board 20 is formed to have a larger cross-sectional area than the second engagement piece 20B provided at the other second rectangular corner 202. This allows the torque input from the connection terminal 40 to the circuit board 20 to be effectively released from the first engagement piece 20A to the case 2, further suppressing damage to the circuit board 20.

[0033] In this embodiment, the case 2 includes a side plate 2D arranged in the X direction of the battery body 10, an end plate 2C arranged in the Z direction of the battery body 10, and an upper plate 2A and a lower plate 2B arranged in the Y direction of the battery body 10. The side plate 2D, in which the insertion hole 30 is provided, is joined to the end plate 2C, the upper plate 2A, and the lower plate 2B. This allows the fastening torque input to the connection terminal 40 to be distributed from the side plate 2D, in which the insertion hole 30 is provided, to the entire case 2, including the end plate 2C, the upper plate 2A, and the lower plate 2B.

[0034] [Modifications] The present invention is not limited to the above-described embodiment, and includes the following modifications within the scope of achieving the object of the present invention.

[0035] [Variation 1] In the above embodiment, the non-circular configuration of the terminal body 41 of the connection terminal 40 has been described, with an example being a substantially D-shaped configuration. However, this is not limiting. Figures 7A and 7B are diagrams showing other examples of the cross-sectional shape of the terminal body 41 of the connection terminal 40. For example, as shown in Figure 7A, the cross-section of the terminal body 41 may be rectangular. In this case, the shapes of the inner circumferential surfaces of the insertion hole 30 and the insulating ring 31 provided in the case 2 are also rectangular. Alternatively, as shown in Figure 7B, the cross-section of the terminal body 41 may be hexagonal. In this case, the shapes of the inner circumferential surfaces of the insertion hole 30 and the insulating ring 31 provided in the case 2 are also hexagonal. As shown by the arrows in Figures 7A and 7B, by making the cross-sectional shape of the terminal body 41 and the shapes of the inner circumferential surfaces of the insertion hole 30 and the insulating ring 31 polygonal, the fastening torque input to the connection terminal 40 can be dispersed in many directions.

[0036] [Variation 2] In the above embodiment, the terminal body 41 of the connection terminal 40 has a uniform cross-sectional shape throughout the X direction, but this is not limiting. It is sufficient that at least the fitting portion of the connection terminal 40, which contacts the inner circumferential surfaces of the insertion hole 30 and the insulating ring 31, is formed in the same shape as the inner circumferential surfaces of the insertion hole 30 and the insulating ring 31, thereby suppressing rotation. For example, the portion of the terminal body 41 closer to the fastening shaft 43 than the fitting portion may be formed in a cylindrical shape, as long as it is insertable through the inner circumferential surfaces of the insertion hole 30 and the insulating ring 31. Furthermore, the portion of the terminal body 41 closer to the circuit board 20 than the fitting portion may have a flange that protrudes outward.

[0037] In the above embodiment, the engaging pieces 20A, 20B protrude in the Z direction from the circuit board 20 and engage with the engaging holes 2E provided in the end plate 2C. However, the engaging pieces 20A, 20B may protrude in the Y direction from the circuit board 20. In this case, engaging holes may be provided in the upper plate 2A and the lower plate 2B.

[0038] [Variation 4] In the above embodiment, the circuit board 20 is illustrated as an example of a support member on which the connection terminals 40 are arranged, but this is not limiting. For example, a configuration may be adopted in which the circuit board 20 is not provided, and each tab 12 and the terminal bus bar 44 are wired and connected in series or parallel, and the terminal bus bar 44 is engaged at a predetermined position on the case 2. In this case, the terminal bus bar 44 serves as the support member of the present disclosure. Even with this configuration, as in the above embodiment, the cross section of the terminal body 41 of the connection terminal 40 is noncircular, and the connection terminal 40 is inserted into a noncircular insertion hole 30 provided in the case, thereby suppressing rotation of the connection terminal 40. By suppressing rotation of the connection terminal 40, rotation of the terminal bus bar 44 is also suppressed, thereby suppressing the inconvenience of the terminal bus bar 44 being disconnected from the tab 12.

[0039] 1...battery module, 2...case, 2A...upper plate, 2B...lower plate, 2C...end plate, 2D...side plate, 2E...engagement hole, 10...battery body, 11...battery cell, 12...tab, 20...circuit board, 20A...first engagement piece, 20B...second engagement piece, 21...base material, 30...insertion hole, 31...insulating ring, 40...connection terminal, 41...terminal body, 42...connection protrusion, 43...fastening shaft, 44...terminal bus bar, 50...coupling bus bar, 201...first rectangular corner portion, 202...second rectangular corner portion, 213...electronic chip, 214...wireless communication chip.

Claims

1. A battery module comprising: a battery body formed by stacking a plurality of battery cells, each having a tab on its side; connection terminals to which the tabs are electrically connected; a support member supporting the connection terminals; and a case that houses the battery body and the support member and has insertion holes through which the connection terminals are inserted, wherein the connection terminals have fastening axes that are parallel to the insertion direction into the insertion holes and have terminal body parts whose cross sections perpendicular to the insertion direction are non-circular, and the shape of the insertion holes perpendicular to the insertion direction is formed to be the same shape as the terminal body parts.

2. The battery module according to claim 1, wherein the tabs extend from the battery cells in a first direction, the battery cells are stacked in a second direction perpendicular to the first direction, the support member is a circuit board arranged opposite the battery body in the first direction, and the connection terminals are provided on the circuit board.

3. The battery module according to claim 2, wherein the circuit board has a rectangular shape when viewed from the first direction, and is positioned and fixed to the case at four rectangular corners.

4. A battery module as described in claim 3, wherein the connection terminal is arranged near one of the four rectangular corners, and the electronic chip provided on the circuit board is arranged between the other rectangular corner where the connection terminal is not provided and the rectangular corner where the connection terminal is provided.

5. A battery module as described in claim 4, wherein the four rectangular corners of the circuit board have engaging portions that engage with the case, and the engaging portion provided at the rectangular corner where the connection terminal is provided has a larger cross-sectional area than the engaging portions provided at the other rectangular corners.

6. A battery module as described in claim 1, wherein the case comprises side plates arranged in a first direction of the battery body and having the insertion holes formed therein, end plates arranged in a second direction of the battery body perpendicular to the first direction, and upper and lower plates arranged in a third direction of the battery body perpendicular to the first and second directions, and the side plates are joined to the end plates, the upper plates, and the lower plates.

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