JP2015026523A - Battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module capable of readily connecting a sensor for detecting a state of battery cells and a control device, even when a cover member is arranged.SOLUTION: A battery module 10 comprises battery cells 11, arranged in parallel, which are held in battery holders 12 made of a resin. The battery cells 11 include connection terminals 20, and the connection terminals 20 adjacent to each other in a parallel arrangement direction of the battery cells 11 are connected by bus bars 22. Bolts 23 which penetrate the bus bars 22 screw into screw holes of the connection terminals 20 of the battery cells 11 so that the bus bars 22 are fixed to the connection terminals 20. Voltage detection terminals 24 are arranged between heads of the bolts 23 and the connection terminals 20. The battery module 10 includes a cover member 31 which faces surfaces, of the battery cells 11, where the connection terminals 20 are arranged. The cover member 31 includes a first cover 32 and a second cover 41. Signal transmission lines 25 of the voltage detection terminals 24 pass between the first cover 32 and the second cover 41.

Description

  The present invention relates to a battery module including a sensor that detects a state of a battery cell.

  The battery module is provided with a sensor for detecting the state of the battery cell. For example, the secondary battery device described in Patent Document 1 is provided with a temperature sensor for measuring the temperature of the battery cell. In the secondary battery device described in Patent Document 1, a cell unit in which a plurality of battery cells are connected in parallel is housed in a center case. The thermistor is provided in the battery cell provided in the position where the temperature becomes highest among the plurality of battery cells and the battery cell provided in the position where the temperature becomes lowest. On the side wall of the center case, an elongated belt-like groove is formed on the inner surface of the side wall facing the battery cell to which the thermistor is attached. The thermistor is accommodated in the groove. The thermistor is electrically connected to the battery monitoring board and outputs the temperature of the battery cell to the battery monitoring board.

JP 2012-38468 A

  By the way, the battery module has a cover for the purpose of suppressing the scattering of the contents of the battery cell when the pressure release valve provided in the battery cell is opened, and for foreign matter to adhere to the connection terminal of the battery cell. A member may be attached. When the cover member is attached, the signal transmission line for connecting the sensor (thermistor) to the control device (battery monitoring board) may have to be detoured to the edge of the cover member. Hateful.

  The objective of this invention is providing the battery module which is easy to connect the sensor and control apparatus which detect the state of a battery cell even if a cover member is provided.

  The battery module that solves the above-described problem includes a plurality of battery cells arranged in parallel, and a first cover and a second cover that are provided in parallel in the direction in which the plurality of battery cells are arranged in parallel. A cover member provided to face one surface of the cell; a sensor that is directly or indirectly joined to the battery cell to detect the state of the battery cell; and a signal transmission line that is joined to the sensor. The gist of the present invention is that the signal transmission line is connected to a control device through between the first cover and the second cover.

  According to this, since the signal transmission line of the sensor passes between the first cover and the second cover and is connected to the control device, the signal transmission line can be controlled without bypassing the edge of the cover member. A signal transmission line can be connected to the device. For this reason, it is easy to connect the sensor and the control device.

In the battery module, it is preferable that the second cover has a pressing portion that bends the signal transmission line toward the first cover.
According to this, the bending direction of the signal transmission line can be directed to the first cover side by pressing the signal transmission line with the pressing portion of the second cover.

In the battery module, it is preferable that the second cover has a wall portion that restricts the signal transmission line from being bent toward the second cover.
According to this, since the signal transmission line is restricted from being bent toward the second cover by the wall portion, the bending direction of the signal transmission line can be directed to the first cover side.

In the battery module, it is preferable that the control device is mounted on the first cover.
According to this, since the signal transmission line is bent toward the first cover, it is easy to connect the signal transmission line to the control device. Further, the first cover can also be used as a mounting member for mounting the control device.

  In the battery module, at least one of the second cover side edge of the first cover and the first cover side edge of the second cover is arranged in the direction in which the battery cells are arranged side by side. It is preferable that a notch is provided, and the signal transmission line is connected to the control device through the notch.

According to this, since the signal transmission line can be passed through the notch, the signal transmission line can be easily passed between the first cover and the second cover.
About the said battery module, it is preferable that the said cover member opposes all the said some battery cells.

According to this, it can suppress suitably that a foreign material adheres to a battery cell.
About the said battery module, it is preferable that the power line for supplying electric power to the said battery cell is connected to the said battery cell provided in the both ends of the juxtaposition direction.

  When the signal transmission line is detoured to the edge of the cover member and is connected to the control device, the power line connected to the battery cells provided at both ends in the juxtaposed direction and the signal transmission line are provided side by side. In this case, noise may occur in the signal transmitted to the control device due to the magnetic field generated by the current flowing through the power line. When noise occurs in the signal, the control device cannot correctly grasp the state of the battery cell. Since the signal transmission line is located between the first cover and the second cover, the power line and the signal transmission line are prevented from being provided side by side. For this reason, the control apparatus can correctly grasp the state of the battery cell.

  According to the present invention, even if the cover member is provided, it is easy to connect the sensor and the control device that detect the state of the battery cell.

The perspective view which shows the battery module of embodiment. The perspective view which shows the battery cell and battery holder of embodiment. (A) is sectional drawing which shows the battery module of embodiment, (b) is an enlarged view which expands and shows a part of battery module. Sectional drawing which shows the battery cell of embodiment. The perspective view which shows the 1st cover of embodiment. The perspective view which shows the 2nd cover of embodiment. The perspective view which shows the cover member of embodiment. Sectional drawing which shows the cover member of a modification. Sectional drawing which shows the cover member of a modification. Sectional drawing which shows the cover member of a modification.

Hereinafter, an embodiment of the battery module will be described.
As shown in FIGS. 1 and 2, the battery module 10 includes a battery cell 11 (for example, a secondary battery such as a lithium ion secondary battery or a nickel metal hydride storage battery) held by a resin battery holder 12. It is installed side by side. In the battery module 10, end plates 14 are provided at both ends of the battery cells 11 in the juxtaposition direction, and the battery cells 11 and the battery holder 12 are restrained by the end plates 14. The end plate 14 is, for example, a bolt inserted from one end plate 14 toward the other end plate 14 through each end plate 14 and each battery holder 12, and a nut on the other end plate 14 side. It is fixed by being screwed together.

  As shown in FIG. 2, the battery holder 12 has a rectangular flat plate-shaped first covering portion 61. At both ends in the longitudinal direction of the first covering part 61, a rectangular flat plate-like second covering part 62 and a third covering part 63 extending in the thickness direction of the first covering part 61 are provided. A first longitudinal end portion 62a of the second covering portion 62 (an end portion opposite to the end portion on which the first covering portion 61 is provided) and a longitudinal first end portion 63a of the third covering portion 63. A rectangular flat plate-like fourth extending between the first end portions 62b and 63b in the short direction of the respective covering portions 62 and 63 is provided on the end portion opposite to the end portion on which the first covering portion 61 is provided. The coating | coated part 64 is provided. A rectangular flat plate connected to each of the covering portions 62 and 63 at the first longitudinal ends 62a and 63a of the second covering portion 62 and the third covering portion 63 and extending in the longitudinal direction of each of the covering portions 62 and 63. A cover holding portion 65 is provided. A locking claw 66 is provided on the surface of each cover holding portion 65 that faces each cover holding portion 65.

  As shown in FIG. 4, the battery cell 11 has an electrode assembly 17 housed inside a case 16. The case 16 includes a bottomed box-shaped case body 18 and a lid 19 that closes an opening of the case body 18. The lid 19 is provided with connection terminals 20 (a positive terminal and a negative terminal) that are electrically connected to the electrode assembly 17. The connection terminal 20 has a screw hole 21 in which an internal thread is formed on the inner peripheral surface. The lid 19 is provided with a pressure release valve 26 that is opened when the pressure in the case 16 becomes higher than a threshold value.

  As shown in FIG. 3, the battery cells 11 are arranged side by side so that the connection terminals 20 adjacent to each other in the direction in which the battery cells 11 are arranged have different polarities, that is, the positive electrode terminal and the negative electrode terminal are adjacent to each other. . The connection terminals 20 adjacent to each other in the direction in which the battery cells 11 are arranged are connected by a bus bar 22. The bus bar 22 is fixed to the connection terminal 20 by a bolt 23 penetrating the bus bar 22 being screwed into the screw hole 21 of the connection terminal 20. Thereby, each battery cell 11 is connected in series.

  A voltage detection terminal 24 as a sensor is provided between the head of the bolt 23 and the connection terminal 20. The voltage detection terminal 24 detects the voltage of the battery cell 11 (the state of the battery cell 11), and is formed of, for example, a metal foil. In the present embodiment, the voltage detection terminal 24 is sandwiched between the head of the bolt 23 and the bus bar 22 provided between the head of the bolt 23 and the connection terminal 20, whereby the connection terminal 20 (battery cell 11 ) Indirectly, and one bus bar 22 is provided. The voltage detection terminal 24 has a signal transmission line 25.

  The battery module 10 includes a cover member 31 that is disposed to face a surface (one surface of the battery cell 11) on which the connection terminals 20 are provided. The cover member 31 faces all the battery cells 11. The cover member 31 is disposed so as to be sandwiched between the cover holding portions 65 of the battery holder 12. The cover member 31 is held by the battery holder 12 by engaging with the engaging claws 66. A region S is defined between the battery cell 11 and the cover member 31. The cover member 31 prevents the contents of the battery cell 11 from scattering when the pressure release valve 26 is opened, and prevents the battery cell 11 from being short-circuited due to foreign matter adhering to the connection terminal 20. It is provided for the purpose. The cover member 31 has a first cover 32 and a second cover 41.

  As shown in FIG. 5, the first cover 32 includes a main body 33 having a rectangular plate shape, and a rectangular plate-like standing portion erected in the thickness direction of the main body 33 from a pair of opposed edge portions of the main body 33. 34. The standing portion 34 is provided over the entire portion between a pair of edge portions different from the edge portion on which the standing portion 34 is provided in the main body 33. One of the edges of the main body 33 where the standing part 34 is not provided (the edge part 35) is provided with the standing part 34 from the surface in the thickness direction of the main body 33 where the standing part 34 is provided. It has the inclined surface 36 which inclines toward the surface which is not made. The edge portion 35 is provided with a notch 37 having an arc shape. In the standing portion 34, an edge in the same direction as the edge 35 of the main body 33 (the edge on the edge 35 side of the main body 33 among the edges in the longitudinal direction) is a thin-walled portion that is continuous with the inclined surface 36. 38.

  As shown in FIG. 6, the second cover 41 has the same shape as that of the first cover 32 except for the edge shape. Specifically, the second cover 41 includes a main body 42 having a rectangular plate shape, and a rectangular plate-like standing portion 43 erected in the thickness direction of the main body 42 from a pair of opposing edges of the main body 42. And have. The standing portion 43 is provided over the whole of a pair of edge portions different from the edge portion on which the standing portion 43 is provided in the main body 42. One of the edges of the main body 42 where the standing portion 43 is not provided (the edge portion 44) is the surface of the main body 42 in the thickness direction from which the standing portion 43 is not provided. It has the inclined surface 45 which inclines toward the provided surface. Further, in the standing portion 43, an edge portion in the same direction as the edge portion 44 of the main body 42 (the edge portion on the edge portion 44 side of the main body 42 among the edge portions in the longitudinal direction) is a thin portion continuous with the inclined surface 45. 46. The main body 42 has a through hole 47 that penetrates in the thickness direction of the main body 42.

  As shown in FIG. 7, the second cover 41 is overlaid on the first cover 32 so that a part of the notch 37 provided on the edge 35 opens in the thickness direction of the main body 33. Specifically, a part of the inclined surface 36 and part of the thin part 38 of the first cover 32 and a part of the inclined surface 45 and part of the thin part 46 of the second cover 41 face each other. In this manner, the second cover 41 is overlaid on the first cover 32. Accordingly, the notch 37 is positioned at the edge 35 on the second cover 41 side in the first cover 32.

  As shown in FIG. 3, a control device 51 (battery ECU) that controls the battery cell 11 according to the state of the battery cell 11 is placed on the first cover 32. The control device 51 is covered with a control device cover 52. The signal transmission line 25 of the voltage detection terminal 24 is connected to the control device 51. A circuit board 53 is provided on the second cover 41. The circuit board 53 is covered with a circuit board cover 54.

  The signal transmission line 25 of each voltage detection terminal 24 is connected to the control device 51 through the notch 37. The signal transmission line 25 is pressed toward the edge 44 of the second cover 41 and bent toward the first cover 32. Therefore, the edge portion 44 of the second cover 41 becomes a pressing portion.

  The power line P1 is connected to the connection terminal 20 of one battery cell 11 among the battery cells 11 at both ends in the juxtaposed direction. The power line P1 extends from between the cover member 31 and the end plate 14 toward a connection target (for example, a load). Moreover, the conductive member 55 is connected to the connection terminal 20 of the other battery cell 11 among the battery cells 11 at both ends in the juxtaposed direction. The conductive member 55 is connected to the circuit board 53 through the through hole 47. A power line P <b> 2 is connected to the circuit board 53. That is, the power line P <b> 2 is connected to the other battery cell 11 among the battery cells 11 at both ends in the juxtaposed direction via the conductive member 55 and the circuit board 53.

Next, the operation of the battery module 10 of the present embodiment will be described.
When the signal transmission line 25 is detoured to the edge of the cover member 31 and is connected to the control device 51, the voltage detection provided in the other battery cell 11 (bus bar 22) among the battery cells 11 at both ends in the juxtaposed direction. In order to connect the signal transmission line 25 of the terminal 24 to the control device 51, it is necessary to extend the signal transmission line 25 to the edge of the cover member 31. For this reason, it is difficult to connect the signal transmission line 25 and the control device 51. In addition, among the battery cells 11 at both ends in the juxtaposed direction, the signal transmission line 25 of the voltage detection terminal 24 provided in one battery cell 11 and the signal transmission of the voltage detection terminal 24 provided in the other battery cell 11. The difference in length from the line 25 is increased. When the difference in the length of the signal transmission line 25 is large, a difference in wiring resistance occurs, and there is a possibility that the voltage information grasped by the control device 51 may be different.

  Furthermore, when the battery cells 11 are connected in series, the power lines P1 and P2 are connected to the battery cells 11 at both ends in the juxtaposed direction. For this reason, when the signal transmission line 25 is connected to the control device 51 by detouring to the edge of the cover member 31, the power lines P1 and P2 and the signal transmission line 25 are provided side by side. Since the current from each battery cell 11 connected in series flows through the power lines P1 and P2, a magnetic field is generated around the power lines P1 and P2. Under the influence of this magnetic field, noise is generated in the signal transmitted by the signal transmission line 25, and the control device 51 may not be able to correctly grasp the voltage of the battery cell 11.

  In the battery module 10 of the present embodiment, since the signal transmission line 25 extends from between the first cover 32 and the second cover 41, there is no need to bypass the signal transmission line 25 to the edge of the cover member 31. .

Therefore, according to the above embodiment, the following effects can be obtained.
(1) The signal transmission line 25 is connected to the control device 51 through between the first cover 32 and the second cover 41. For this reason, it is not necessary to extend the signal transmission line 25 to the edge of the cover member 31, and the signal transmission line 25 is easily connected to the control device 51.

  (2) Moreover, since it is not necessary to extend the signal transmission line 25 to the edge part of the cover member 31, it is suppressed that the power lines P1, P2 and the signal transmission line 25 are provided side by side. For this reason, noise generated in the signal is suppressed by the magnetic field generated around the power lines P <b> 1 and P <b> 2, and the control device 51 can accurately grasp the state of the battery cell 11.

  (3) The edge 44 of the second cover 41 presses the signal transmission line 25 toward the first cover 32. For this reason, the signal transmission line 25 can be bent toward the first cover 32.

  (4) Since the control device 51 is placed on the first cover 32, it is easy to connect the signal transmission line 25 pressed by the second cover 41 to the control device 51. Further, the first cover 32 can also be used as a mounting member for mounting the control device.

  (5) Since the signal transmission line 25 is connected to the control device 51 from the region S through the first cover 32 and the second cover 41, the signal transmission line 25 of each voltage detection terminal 24 The difference in length is small. For this reason, it is suppressed that the voltage information which the control apparatus 51 grasps | ascertains by the difference in the wiring resistance of the signal transmission line 25 arises.

  (6) Since the notch 37 is provided in the edge 35 of the first cover 32, the signal transmission line 25 is extended from between the first cover 32 and the second cover 41 to the outside of the region S. Can be installed.

  (7) The cover member 31 faces the surface on which the connection terminals 20 of all the battery cells 11 are provided. For this reason, it can suppress suitably that a foreign material adheres to the surface in which the connection terminal 20 of the battery cell 11 was provided.

  (8) By the way, it is conceivable that a hole is provided in the cover member 31 made of a single member, and the signal transmission line 25 is extended outside the region S from the hole. However, since the signal transmission line 25 is provided with a connector for connecting to the control device 51, it is necessary to make the size of the hole larger than that of the connector in order to pass the signal transmission line 25 through the hole. When the signal transmission line 25 is extended from between the covers using the cover member 31 composed of a plurality of covers, the cover may be disposed so as to sandwich the signal transmission line 25, and it is not necessary to pass the connector through the hole. For this reason, after connecting a connector to the control apparatus 51, a cover can be provided so that the signal transmission line 25 may be pinched | interposed, and it is not necessary to provide a larger hole in the cover member 31 than a connector. For this reason, it is suppressed that a foreign material adheres to the connection terminal 20 through a hole.

In addition, you may change embodiment as follows.
As shown in FIG. 8, a wall portion 56 erected on the edge 44 of the second cover 41 in a direction opposite to the battery cell 11 side in the thickness direction of the main body 42 of the second cover 41. May be provided. The wall portion 56 restricts the signal transmission line 25 extending outside the region S from between the first cover 32 and the second cover 41 from being bent toward the second cover 41. More specifically, when the signal transmission line 25 is bent toward the second cover 41, the signal transmission line 25 comes into contact with the wall portion 56, so that it is difficult to bend toward the second cover 41. For this reason, it is easy to bend the signal transmission line 25 to the first cover 32 side. The wall portion 56 may be provided at a position away from the edge portion 44.

  As shown in FIG. 9, the first cover 32 may not be provided with the notch 37 so that the edges 35 and 44 of the first cover 32 and the second cover 41 do not overlap each other. In this case, the first cover 32 and the second cover 41 are made longer by the second cover 41 being longer than the first cover 32 by the distance from the surface on which the connection terminal 20 is provided in the battery cell 11. When the second cover 41 is assembled, the second cover 41 is moved toward the first cover 32, and the signal transmission line 25 can be pressed toward the first cover 32 at the edge 44 of the second cover 41. When it is not necessary to press the signal transmission line 25, the distance from the surface on which the connection terminal 20 is provided in the battery cell 11 is set to the same distance or the second distance between the first cover 32 and the second cover 41. The first cover 32 may be longer than the first cover 41.

  As shown in FIG. 10, notches 37 are provided on both the edge 35 on the second cover 41 side of the first cover 32 and the edge 44 on the first cover 32 side of the second cover 41. Also good.

(Circle) the cover member 31 may be comprised from the 3 or more cover. In this case, one of the adjacent covers is a first cover and the other is a second cover.
In the embodiment, the voltage detection terminal 24 is indirectly attached to the battery cell 11 via the bus bar 22, but the voltage detection terminal 24 may be directly attached to the connection terminal 20 (battery cell 11). .

  (Circle) the battery cell 11 may be connected in parallel. In this case, the power lines P <b> 1 and P <b> 2 may be connected to the battery cells 11 at both ends in the juxtaposed direction, or may be connected to other battery cells 11.

The first cover 32 and the second cover 41 do not need to have the standing portions 34 and 43 and may be configured only by the main bodies 33 and 42.
(Circle) the battery cell 11 does not need to be hold | maintained at the battery holder 12, and only the battery cell 11 may be arranged in parallel.

  A temperature sensor that detects the temperature of the battery cell 11 may be provided as a sensor, and the temperature may be detected as the state of the battery cell 11. The temperature sensor may be directly attached to the battery cell 11 or may be indirectly attached to the battery cell 11 by being attached to the bus bar 22 or the like as in the present embodiment.

  (Circle) the control apparatus 51 does not need to be mounted in the cover member 31, for example, when the battery module 10 is accommodated in a case, it may be accommodated in the case.

(Circle) the cover member 31 may be arrange | positioned so that the surface different from the surface in which the connection terminal 20 of the battery cell 11 is provided may be opposed.
The cover member 31 may not be opposed to all the battery cells 11 and may be opposed to some of the battery cells 11.

  P1, P2 ... power line, 10 ... battery module, 11 ... battery cell, 20 ... connection terminal, 24 ... voltage detection terminal, 25 ... signal transmission line, 31 ... cover member, 32 ... first cover, 37 ... notch 41 ... second cover, 51 ... control device.

Claims (7)

A plurality of battery cells arranged side by side;
A first cover and a second cover provided side by side in the direction in which the plurality of battery cells are arranged, and a cover member provided to face one surface of the battery cells;
A sensor that is directly or indirectly joined to the battery cell and detects the state of the battery cell;
A signal transmission line joined to the sensor,
The battery module, wherein the signal transmission line is connected to a control device through between the first cover and the second cover.   The battery module according to claim 1, wherein the second cover includes a pressing portion that bends the signal transmission line toward the first cover.   3. The battery module according to claim 1, wherein the second cover has a wall portion that restricts the signal transmission line from being bent toward the second cover. 4.   The battery module according to claim 2, wherein the control device is placed on the first cover. At least one of the edge part on the second cover side of the first cover and the edge part on the first cover side of the second cover is cut out in a direction in which the battery cells are arranged side by side. A notch,
The battery module according to any one of claims 1 to 4, wherein the signal transmission line is connected to the control device through the notch.   The battery module according to claim 1, wherein the cover member faces all of the plurality of battery cells.   A power line for supplying electric power to the battery cells is connected to the battery cells provided at both ends in the juxtaposed direction. The battery module described in 1.