阅读说明：本技术 电池模块 (Battery module ) 是由 因和久 板谷弘毅 中野笃 于 2019-05-30 设计创作，主要内容包括：本发明提供一种电池模块,其在电池单元层叠体的上表面上配置有传感器装置,同时能够抑制传感器装置的松动。电池模块(1)具备通过层叠多个电池单元(21)而构成的电池单元层叠体(2)、以及对各电池单元(21)的电压进行检测的传感器装置(7)。传感器装置(7)配置在电池单元层叠体(2)的上表面,且在相邻的电池单元(21)之间设置有绝缘板(22)。传感器装置(7)沿上下方向固定于在层叠方向上分开的至少两个绝缘板(22)上。(The invention provides a battery module, which is provided with a sensor device on the upper surface of a battery unit laminated body and can inhibit the sensor device from loosening. A battery module (1) is provided with a battery cell stack (2) formed by stacking a plurality of battery cells (21), and a sensor device (7) for detecting the voltage of each battery cell (21). The sensor device (7) is disposed on the upper surface of the battery cell stack (2), and an insulating plate (22) is provided between adjacent battery cells (21). The sensor device (7) is fixed to at least two insulating plates (22) separated in the stacking direction in the vertical direction.)

1. A battery module comprising a battery cell stack formed by stacking a plurality of battery cells, and a sensor device for detecting the voltage of each battery cell,

the sensor device is disposed on an upper surface of the battery cell stack,

an insulating plate is disposed between the adjacent battery cells,

the sensor device is fixed to at least two of the insulating plates separated in the stacking direction in the up-down direction.

2. The battery module of claim 1,

the sensor device comprises a substrate, an electronic component mounted on the substrate, and a case for accommodating the substrate and the electronic component,

the housing has a fixing portion fixed to the insulating plate.

3. The battery module of claim 1,

the sensor device comprises a substrate and an electronic component mounted on the substrate,

the substrate has a fixing portion fixed to the insulating plate.

4. The battery module according to any one of claims 1 to 3,

the insulating plate has a projection portion projecting upward,

the sensor device has a fixing portion including a hole that receives the protruding arrangement.

5. The battery module of claim 4,

the hole is an elongated hole elongated in the stacking direction.

6. The battery module of claim 5,

a pair of end plates are provided on both ends of the battery cell laminate in the lamination direction,

the sensor device is fixed to one of the pair of end plates so as to be immovable in the stacking direction.

7. The battery module according to claim 5 or 6,

the sensor device is fixed by pushing a nut in a state that the protruding arrangement part arranged on the insulating plate penetrates through the fixing part.

Technical Field

The present invention relates to a battery module mounted on an electric vehicle or the like.

Background

Conventionally, a battery module is mounted on an electric vehicle or the like. For example, patent document 1 discloses a battery module including a battery cell stack formed by stacking a plurality of battery cells, and a sensor device for detecting the voltage of each battery cell.

Prior art documents

Patent document 1: japanese patent laid-open publication No. 2016-072181

Problems to be solved by the invention

In recent years, in such a battery module, the capacity of the battery has been increased, and the size expansion caused by the swelling of the battery cells due to temperature change and aging deterioration has not been negligible. Therefore, it is difficult to firmly fix the sensor device to the upper surface of the battery cell stack at two or more points, and the sensor device may be loosened due to vibration while the vehicle is running.

Disclosure of Invention

The invention provides a battery module, which is provided with a sensor device on the upper surface of a battery unit laminated body and can inhibit the sensor device from loosening.

Means for solving the problems

The battery module of the present invention includes a battery cell stack including a plurality of battery cells stacked one on another, and a sensor device for detecting a voltage of each of the battery cells,

the sensor device is disposed on an upper surface of the battery cell stack,

an insulating plate is disposed between the adjacent battery cells,

the sensor device is fixed to at least two of the insulating plates separated in the stacking direction in the up-down direction.

Effects of the invention

According to the present invention, the sensor device is fixed to at least two insulating plates that are separated in the stacking direction in the vertical direction, and therefore the battery module is able to suppress the looseness of the sensor device while the sensor device is arranged on the upper surface of the battery cell stack.

Drawings

Fig. 1 is a perspective view of a battery module according to an embodiment of the present invention, viewed from obliquely above.

Fig. 2 is an exploded perspective view of the battery module of fig. 1.

Fig. 3 is a top view of the battery module of fig. 1.

Fig. 4 is a perspective view of the sensor device of the battery module of fig. 1 viewed obliquely from below.

Fig. 5 is a sectional view a-a of fig. 4.

Fig. 6 is an enlarged perspective view of a main portion of the battery module of fig. 1 viewed from obliquely above.

Fig. 7 is a sectional view B-B of fig. 6.

Description of reference numerals:

1a battery module;

2 a stack of battery cells;

21 a battery cell;

22 an insulating plate;

221 a protruding setting part;

3, end plates;

7 a sensor device;

71 a substrate;

72 an electronic component;

73 a housing;

7311a first fixing part;

7311a hole;

76 push nut (push nut).

Detailed Description

Hereinafter, each embodiment of the battery module according to the present invention will be described with reference to the drawings. It should be noted that the drawings are viewed in the direction of the reference numerals.

[ Battery Module ]

As shown in fig. 1 to 3, a battery module 1 according to the present embodiment includes: a battery cell laminate 2 configured by laminating a plurality of battery cells 21 in the front-rear direction, the battery cell laminate 2 having a front surface, a rear surface, a left surface, a right surface, an upper surface, and a lower surface; a pair of end plates 3 disposed on the front and rear surfaces of the battery cell laminate 2; a pair of side frames 4 disposed on the left and right surfaces of the battery cell laminate 2 and connecting the pair of end plates 3; a lower plate 5 disposed on a lower surface of the cell laminate 2; a sensor device 7 that is disposed on the upper surface of the battery cell stack 2 and detects the voltage of each battery cell 21; and a top cover 6 that covers a region on the upper surface of the battery cell stack 2 where the sensor device 7 is not mounted.

In this specification and the like, for the sake of simplicity and clarity of description, the stacking direction of the battery cells 21 is defined as the front-rear direction, and the direction orthogonal to the stacking direction of the battery cells 21 is defined as the left-right direction (width direction) and the up-down direction (height direction), regardless of the front-rear direction of a product on which the battery module 1 is mounted. That is, when the battery module 1 is mounted on a vehicle, the stacking direction of the battery cells 21 may be the same as the front-rear direction of the vehicle, may be the vertical direction, the horizontal direction, or may be a direction inclined from these directions. In the drawing, the front of the battery module 1 is denoted as Fr, the rear is denoted as Rr, the left side is denoted as L, the right side is denoted as R, the upper side is denoted as U, and the lower side is denoted as D.

(Battery cell laminate)

As shown in fig. 2, the battery cell stack 2 is configured by alternately stacking a plurality of battery cells 21 and a plurality of insulating plates 22 in the front-rear direction. A plurality of bus bars 23 electrically connected to the terminals 211 of the battery cells 21 are arranged on the upper surface of the cell laminate 2. The plurality of bus bars 23 connect the terminals 211 of the adjacent battery cells 21 to each other so that the plurality of battery cells 21 are electrically connected in series. Specifically, the plurality of battery cells 21 are stacked such that the positive side terminal 211 and the negative side terminal 211 are sequentially inverted left and right, and the plurality of bus bars 23 sequentially connect the positive side (or negative side) terminal 211 of the battery cell 21 adjacent to the upstream side in the cell stacking direction and the negative side (or positive side) terminal 211 of the battery cell 21 adjacent to the downstream side in the cell stacking direction, thereby electrically connecting the plurality of battery cells 21 in series.

A bus bar plate 24 that holds the plurality of bus bars 23 is provided on the upper surface of the cell laminate 2. The bus bar plate 24 includes a plurality of bus bar holding portions 241, and when the bus bar plate 24 is placed on the upper surface of the battery cell stack 2 after the plurality of bus bars 23 are held by the bus bar holding portions 241, the plurality of bus bars 23 are positioned at predetermined positions where they can be connected to the corresponding terminals 211. The bus bar plate 24 of the present embodiment is not a jig for detaching the bus bar 23 after being connected to the terminal 211, but is a component of the battery module 1 that maintains the mounted state even after the bus bar 23 is connected to the terminal 211.

It is known that the battery cell 21 expands due to temperature change or aging degradation. The battery unit 21 has a rectangular parallelepiped shape in which the length in the up-down direction is longer than the length in the front-rear direction, and the length in the left-right direction is longer than the length in the up-down direction. Therefore, the areas of the front and rear surfaces of the battery cell 21 are much larger than those of the left, right, upper, and lower surfaces, and the left-right direction central portion and the up-down direction central portion thereof are easily expanded at the front and rear surfaces of the battery cell 21. When the battery cells 21 expand in the front-rear direction, stress acts on the bus bars 23, and the bus bars 23 connect the terminals 211 of the battery cells 21 to each other. In order to alleviate the stress that acts as a result of the expansion of the battery cells 21, the bus bar 23 of the present embodiment has a bent portion 231 that protrudes upward at an intermediate portion in the front-rear direction.

(end plate)

As shown in fig. 1 to 3, the pair of end plates 3 are disposed on the front and rear surfaces of the cell stack 2, and receive a load in the cell stacking direction of the cell stack 2 due to expansion of the cells 21. The end plate 3 of the present embodiment is formed using an aluminum extrusion material, and a plurality of fastening portions 31 fastened to the side frames 4 via bolts B1 are provided at both left and right end portions of the outer surface that does not face the cell laminated body 2. Further, an external connection terminal plate 32 is provided on the upper surface of the pair of end plates 3, the external connection terminal plate 32 is used for transmitting and receiving electric power between the battery module 1 and an external electric device, and a sensor fixing portion 33 is provided on the upper surface of one of the end plates 3, and the sensor device 7 is fixed to the sensor fixing portion 33 via a bolt B2.

(side frame)

As shown in fig. 1 to 3, the side frame 4 is formed by press working a metal plate material, and includes: a side frame main body 41 along a left or right surface of the cell laminated body 2; front flange portions 42 extending from the front ends of the side frame bodies 41 in a direction in which the front ends of the front end plates 3 approach each other; a rear flange portion 43 extending from the rear end of the side frame body 41 in a direction to approach each other along the rear surface of the rear end plate 3; upper flange portions 44 extending from the upper ends of the side frame main bodies 41 in the direction in which the upper surfaces of the cell laminated bodies 2 approach each other; and a lower flange portion 45 extending from the lower end of the side frame main body 41 in a direction in which the lower surfaces of the cell stack 2 (lower plate 5) approach each other.

The front flange portion 42 and the rear flange portion 43 are fastened and connected to the front end plate 3 or the rear end plate 3 via bolts B1. Thereby, the pair of end plates 3 are coupled via the pair of side frames 4. The pair of side frames 4 allow relative displacement of the end plates 3 in the front-rear direction when a load in the cell stacking direction of the cell stacked body 2 is increased. For example, the relative displacement of the end plates 3 in the front-rear direction with respect to each other is permitted by deformation of the side frame main bodies 41 in the front-rear direction, a change in the angle of the side frame main bodies 41 and the front flange portions 42 or the side frame main bodies 41 and the rear flange portions 43, or the like.

The upper flange portion 44 and the lower flange portion 45 sandwich the cell laminate 2 and the lower plate 5 from the top-bottom direction at the left end portion and the right end portion of the cell laminate 2. This suppresses the relative positional variation in the vertical direction of the battery cell laminate 2, the side frames 4, and the lower plate 5, and allows the plurality of battery cells 21 constituting the battery cell laminate 2 to be aligned.

The upper flange portion 44 of the present embodiment is formed of a plurality of elastic pieces 44a arranged in the front-rear direction, and the number and position of the elastic pieces 44a correspond to the number and position of the battery cells 21 stacked in the front-rear direction. Thus, the upper flange portion 44 has appropriate elasticity, and can elastically hold the plurality of battery cells 21 individually. The lower flange portion 45 is fixed to or engaged with the lower plate 5 via a restricted portion (not shown).

(lower plate)

As shown in fig. 1 and 2, the lower plate 5 is formed using an aluminum extrusion material, and includes: a lower plate main body 51 extending along the lower surfaces of the cell stacked body 2 and the end plates 3; a plurality of fixing portions 52 fixed to a module support structure (not shown) that supports the battery module 1; and a regulating portion (not shown) for regulating the lower flange portion 45 of the side frame 4.

(sensor device)

As shown in fig. 4 and 5, the sensor device 7 includes: a substrate 71; an electronic component 72 mounted on the substrate 71; a case 73 that houses the substrate 71 and the electronic component 72; and a voltage detection connector 74 and a detection signal output connector 75 disposed on a side surface of the housing 73. The sensor device 7 of the present embodiment includes two voltage detection connectors 74 in order to be able to detect the voltage of the battery module 1, but the number of the voltage detection connectors 74 may be one, or may be three or more.

The substrate 71 of the present embodiment is a printed substrate having a rectangular shape in a plan view, which is long in the front-rear direction, and on the upper surface of which wiring is printed, and on the lower surface of which an electronic component 72, a voltage detection connector 74, and a detection signal output connector 75 are mounted.

The housing 73 includes a housing main body 731 covering the lower surface side of the substrate 71, and a cover housing 732 covering the upper surface side of the substrate 71. The case main body 731 includes a plurality of first fixing portions 7311 and one second fixing portion 7312, and is fixed to the upper surface of the battery cell stack 2 via the fixing portions 7311 and 7312. A specific fixing structure of the first fixing portion 7311 and the second fixing portion 7312 to the upper surface of the cell stack 2 will be described later.

The voltage detection connector 74 is connected to each bus bar 23 via a plurality of voltage detection lines 9. One end sides of the plurality of voltage detection lines 9 are connected to the voltage detection connector 74 of the sensor device 7 via a cable-side connector. The other end sides of the plurality of voltage detection lines 9 are connected to the respective bus bars 23 through a space secured between the upper surface of the cell laminated body 2 and the lower surface of the sensor device 7.

One end side of a detection signal output line (not shown) is connected to the detection signal output connector 75. The other end of the detection signal output line is connected to a charge/discharge control unit (not shown) of the vehicle, and the voltage detection signal of each battery cell 21 output from the sensor device 7 is input to the charge/discharge control unit of the vehicle via the detection signal output line.

(fixing Structure of sensor device)

Next, a specific fixing structure of the sensor device 7 to the battery cell stack 2 will be described.

As shown in fig. 1 to 4, the first fixing portions 7311 are provided to protrude from the left and right sides of the housing main body 731 at predetermined intervals in the front-rear direction, and are fixed to the insulating plates 22 spaced apart in the front-rear direction so as to be immovable in the up-down direction and movable in the front-rear direction. Specifically, as shown in fig. 6 and 7, the insulating plate 22 has a cylindrical projecting portion 221 projecting upward, and the first fixing portion 7311 has a hole 7311a for receiving the projecting portion 221 in a state of passing through from below. The hole 7311a is an elongated hole that is long in the front-rear direction and allows relative movement between the insulating plate 22 and the sensor device 7 in the front-rear direction due to expansion of the battery cell 21.

As shown in fig. 6 and 7, the first fixing portion 7311 of the housing main body 731 passes through the projection portion 221 of the insulating plate 22 from above, and then the push nut 76 is fixed in the vertical direction, and the push nut 76 is assembled by pressing the projection portion 221 from above. The pushing nut 76 has a plurality of claws 762 inclined upward to the peripheral edge of a hole 761 formed in the central portion, and when the pushing nut 76 is pushed into the protruding portion 221 from above, the plurality of claws 762 sink into the outer peripheral portion of the protruding portion 221, so that the upward removal of the pushing nut 76 can be restricted. Thereby, the first fixing portion 7311 of the case main body 731 is fixed to the projection portion 221 of the insulating plate 22 in the up-down direction via the thrusting nut 76, and the first fixing portion 7311 of the case main body 731 is allowed to move in the front-back direction with respect to the projection portion 221 of the insulating plate 22 through the hole 7311a constituted by the long hole.

In the battery module 1 of the present embodiment, the protrusion 221 of the insulating plate 22 and the pushing nut 76 are used as a fixing portion and a fixing tool for the bus bar plate 24. Specifically, the bus bar plate 24 has a plurality of holes 242 through which the protruding portions 221 of the insulating plate 22 pass, is sandwiched between the upper surface of the battery cell 21 and the first fixing portions 7311 of the case main body 731 through which the protruding portions 221 of the insulating plate 22 pass, and is fixed to the protruding portions 221 of the insulating plate 22 in the up-down direction via the first fixing portions 7311 and the pushing nuts 76.

The second fixing portion 7312 is provided to protrude from one end portion (in the present embodiment, the front end portion) in the front-rear direction of the housing main body 731, and is fixed to the sensor fixing portion 33 provided on one of the front end plate 3 and the rear end plate 3 via a bolt B2 so as to be immovable in the front-rear direction and the up-down direction. Thus, the sensor device 7 is fixed in the vertical direction by the plurality of first fixing portions 7311 and the single second fixing portion 7312, and thus can suppress the occurrence of vertical looseness due to vibration during vehicle travel. Further, the sensor device 7 is fixed in the front-rear direction by the single second fixing portion 7312, and thus, not only can the front-rear direction play caused by the vibration during the traveling of the vehicle be suppressed, but also the occurrence of stress in the sensor device 7 due to the expansion of the battery cell 21 can be prevented.

The above embodiment can be modified and improved as appropriate. For example, although the sensor device 7 of the above embodiment is configured such that the first fixing portion 7311 and the second fixing portion 7312 are provided on the case 73 accommodating the substrate 71 and these fixing portions 7311 and 7312 are fixed to the cell stack 2, in a battery module which has no case and in which the substrate itself is fixed to the cell stack in an exposed state, holes corresponding to the first fixing portion and the second fixing portion of the above embodiment can be provided in the substrate itself and these holes can be fixed to the cell stack 2 with the same fixing structure as the first fixing portion and the second fixing portion of the above embodiment.

[ general ] A

In the present specification, at least the following matters are described. Although the corresponding components and the like in the above embodiments are shown in parentheses, the present invention is not limited to these.

(1) A battery module (battery module 1) comprising a battery cell stack (battery cell stack 2) formed by stacking a plurality of battery cells (battery cells 21), and a sensor device (sensor device 7) for detecting the voltage of each battery cell,

the sensor device is disposed on an upper surface of the battery cell stack,

an insulating plate (insulating plate 22) is provided between the adjacent battery cells,

the sensor device is fixed to at least two of the insulating plates separated in the stacking direction in the up-down direction.

According to (1), the sensor device is fixed to at least two insulating plates that are separated in the stacking direction in the up-down direction, whereby the battery module is able to suppress looseness of the sensor device while the sensor device is arranged on the upper surface of the battery cell stack.

(2) The battery module according to (1), wherein,

the sensor device comprises a substrate (substrate 71), an electronic component (electronic component 72) mounted on the substrate, and a case (housing 73) for accommodating the substrate and the electronic component,

the case has a fixing portion (first fixing portion 7311) fixed to the insulating plate.

According to (2), the substrate and the electronic component are accommodated in the case, so that the substrate and the like can be protected by the case, and are fixed to the insulating plate by the fixing portion provided in the case.

(3) The battery module according to (1), wherein,

the sensor device comprises a substrate (substrate 71) and an electronic component (electronic component 72) mounted on the substrate,

the substrate has a fixing portion fixed to the insulating plate.

According to (3), the number of components of the sensor device can be reduced, and the sensor device can be fixed to the insulating plate by the fixing portion provided on the substrate.

(4) The battery module according to any one of (1) to (3),

the insulating plate has a projection (projection 221) projecting upward,

the sensor device has a fixing portion (first fixing portion 7311) including a hole (hole 7311a) that accommodates the projection portion.

According to (4), the fixed portion of the sensor device is engaged with the protruding portion of the insulating plate, so that the movement in the stacking direction is restricted in addition to the movement in the vertical direction.

(5) The battery module according to (4), wherein,

the hole is an elongated hole elongated in the stacking direction.

According to (5), relative movement between the insulating plate and the sensor device in the cell stacking direction, which is accompanied by swelling of the battery cell, can be allowed.

(6) The battery module according to (5), wherein,

a pair of end plates (end plates 3) are provided at both ends of the battery cell laminate in the lamination direction,

the sensor device is fixed to one of the pair of end plates so as to be immovable in the stacking direction.

According to (6), the sensor device is positioned in the stacking direction with respect to the one end plate, and relative movement of the sensor device in the stacking direction with respect to the battery cell stack is allowed.

(7) The battery module according to (5) or (6), wherein,

the sensor device is fixed by a pushing nut (pushing nut 76) in a state where the protruding portion provided on the insulating plate passes through the fixing portion.

According to (7), the sensor device suppresses the loosening in the vertical direction by pushing the nut, and allows the movement in the stacking direction.