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 2019-06-04 设计创作，主要内容包括：本发明提供一种电池模块,其能够在电池单元层叠体的上表面上配置传感器装置且抑制高度尺寸。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)配置于电池单元层叠体(2)的上表面。在传感器装置(7)上设置有向下方鼓出的传感器鼓出部(731a),且在电池单元层叠体(2)的上表面上设置有容纳传感器鼓出部(731a)的低位部(243)。(The invention provides a battery module, which can arrange a sensor device on the upper surface of a battery unit laminated body and restrain the height dimension. 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). A sensor device (7) is provided with a sensor projection part (731a) projecting downward, and a lower part (243) for accommodating the sensor projection part (731a) is provided on the upper surface of the cell laminated body (2).)

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,

the sensor device is provided with a sensor bulging part bulging downwards,

a lower portion that accommodates the sensor bulging portion is provided on the upper surface of the battery cell laminate.

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 sensor bulge is arranged on the lower surface of the shell.

3. The battery module of claim 2,

the electronic component is mounted on the lower surface of the substrate,

the sensor projection portion is an electronic component housing portion that houses the electronic component.

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

the lower portion is formed of a bus bar plate mounted on the upper surface of the cell stack.

5. The battery module of claim 4,

the bus bar plate includes a high portion formed of terminal portions of voltage detection lines connected to a bus bar, and the low portion provided between the terminal portions.

6. The battery module of claim 5,

the bus bar plate is provided with a voltage detection line housing portion that houses the plurality of voltage detection lines at a position that does not overlap the high-position portion.

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

However, in the battery module of patent document 1, since the sensor device is disposed on the upper surface of the battery cell laminate, there is a possibility that the height dimension of the battery module may be significantly increased.

Disclosure of Invention

The invention provides a battery module, which is capable of suppressing height dimension while arranging a sensor device on the upper surface of a battery cell laminate.

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,

the sensor device is provided with a sensor bulging part bulging downwards,

a lower portion that accommodates the sensor bulging portion is provided on the upper surface of the battery cell laminate.

Effects of the invention

According to the present invention, since the sensor device is provided with the sensor bulging portion bulging downward and the lower portion accommodating the sensor bulging portion is provided on the upper surface of the battery cell stack, the battery module can be configured with the sensor device on the upper surface of the battery cell stack and the height dimension of the battery module can be suppressed by the nesting structure.

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.

Description of reference numerals:

1a battery module;

2 a stack of battery cells;

21 a battery cell;

23 bus bar;

24 bus plates;

242 high portion;

243 low part;

a 244 voltage detection line housing section;

7 a sensor device;

71 a substrate;

72 an electronic component;

73 a housing;

731a sensor bulge;

734 an electronic component housing part;

9, a voltage detection line;

92 terminal portion.

Detailed Description

Hereinafter, an embodiment of a 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 directions orthogonal to the stacking direction of the battery cells 21 are defined as the left-right direction and the up-down 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)

Referring also to 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; a voltage detection connector 74 disposed on a side surface of the housing 73 and connected to each bus bar 23 via a plurality of voltage detection lines 9; and a detection signal output connector 75 disposed on a side surface of the case 73 and connected to a charge/discharge control unit (not shown) of the vehicle via a plurality of detection signal output lines (not shown). In order to be able to detect the voltages of the two battery modules 1, the sensor device 7 of the present embodiment includes two voltage detection connectors 74, 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 electronic component 72 includes a transformer 721 and an electrolytic capacitor 722 having a relatively large height dimension. Further, the electronic component 72 has different clearances CL1 to CL3 from the case 73 depending on the amount of heat radiation and the like. For example, in the case of the voltage detection connector 74 with a small amount of heat radiation, a small clearance CL3 may be ensured between the voltage detection connector and the case 73, but in the case of the transformer 721 and the electrolytic capacitor 722 with a large amount of heat radiation, it is necessary to ensure clearances CL1 and CL2 that are larger than the clearance CL 3.

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 cover case 732 has a substantially flat upper surface, and a sensor projection 731a projecting downward is formed on a lower surface of the case main body 731. The sensor projecting portion 731a of the present embodiment is configured to form an electronic component housing portion 734 for housing the transformer 721 and the electrolytic capacitor 722 in the case 73, and the transformer 721 and the electrolytic capacitor 722 have relatively large height dimensions and require large clearances CL1 and CL2 with the case 73, and three sensor projecting portions 731a formed in a rectangular shape in a bottom view are provided at predetermined intervals in the front-rear direction.

Further, a fixing portion 731B fixed to the sensor fixing portion 33 of the end plate 3 via a bolt B2 is provided at one end portion in the front-rear direction of the case main body 731, and a plurality of engaging portions 731c engaging with the plurality of insulating plates 22 are provided at each of the left and right side portions of the case main body 731.

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. As shown in fig. 3, terminal portions 92 for connection to the respective bus bars 23 are provided on the other end sides of the plurality of voltage detection lines 9, and are connected to the bus bars 23 via the terminal portions 92. Specifically, the terminal portion 92 includes a terminal body 921 and a caulking portion 922 connected to the other end portion of the voltage detection line 9 by caulking, and the terminal body 921 is connected to the terminal portion 232 provided on the bus bar 23 side by welding or the like.

The terminal portion 92 on the voltage detection line 9 side and the terminal portion 232 on the bus bar 23 side are disposed on the upper surface of the bus bar plate 24. The terminal body 921 of the terminal portion 92 and the terminal portion 232 on the bus bar 23 side are thin-plate metal members and therefore have a small height, but the swaged portion 922 of the terminal portion 92 is swaged to the voltage detection line 9 and therefore has a larger height than the terminal body 921 of the terminal portion 92. That is, the portion of the upper surface of the bus bar plate 24 where the caulking portion 922 of the terminal portion 92 is disposed is the high portion 242, and the portion between the high portion 242 and the high portion 242 adjacent to each other in the front-rear direction is the low portion 243. Further, although one end sides of the plurality of voltage detection lines 9 are bundled and only the other end sides are routed toward the respective bus bars 23, the bundling portions 93 of the plurality of voltage detection lines 9 are accommodated in the voltage detection line accommodating portions 244 on the upper surface of the bus bar plate 24, and the voltage detection line accommodating portions 244 are secured in the region avoiding the high-position portion 242.

(nested Structure of sensor device and Battery cell Stack)

Next, a nesting structure of the sensor device 7 and the cell stack 2 will be described.

In the battery module 1 configured as described above, since the sensor device 7 is disposed on the upper surface of the cell laminate 2, the height dimension of the battery module 1 may be significantly increased. In the battery module 1 according to the embodiment of the present invention, the sensor projecting portion 731a projecting downward from the lower surface of the sensor device 7 is accommodated in the low position portion 243 provided on the upper surface of the cell stack 2 (bus bar plate 24). In this way, the battery module 1 is provided with the sensor device 7 on the upper surface of the cell laminate 2, while being able to reduce the height dimension by the nested structure of the sensor device 7 and the cell laminate 2.

Further, since the sensor device 7 includes the substrate 71, the electronic component 72 mounted on the substrate 71, and the case 73 accommodating the substrate 71 and the electronic component 72, and the sensor bulging portion 731a is provided on the lower surface of the case 73, the substrate 71 and the electronic component 72 are accommodated in the case 73, the substrate 71 and the like can be protected by the case 73, and the height dimension can be reduced by the nested structure.

Since the electronic component 72 is mounted on the lower surface of the substrate 71 and the sensor projection portion 731a serves as the electronic component storing portion 734 for storing the electronic component 72, the sensor device 7 can be downsized by projecting only the outer wall of the electronic component storing portion 734 of a required height to serve as the sensor projection portion 731 a.

Since the low portion 243 is formed by the bus bar plate 24 mounted on the upper surface of the cell laminate 2, the height of the sensor projecting portion 731a can be absorbed by the irregularities of the bus bar plate 24.

Further, since the high portion 242 of the bus bar plate 24 is the caulking portion 922 provided on the terminal portion 92 of the voltage detection line 9 connected to the bus bar 23 and the low portion 243 is provided between the caulking portions 922, the height of the caulking portion 922 connecting the voltage detection line 9 and the terminal portion 92 by caulking is increased, but the height of the sensor bulging portion 731a can be absorbed by the low portion 243 avoiding the caulking portion 922 of the terminal portion 92.

The other ends of the plurality of voltage detection lines 9 are connected to the bus bar 23, are bundled at one end, pass through the space between the lower surface of the sensor device 7 and the upper surface of the bus bar plate 24, and are pulled out from the space to be connected to the voltage detection connector 74 of the sensor device 7, but since the voltage detection line housing portion 244 is provided at a position not overlapping the high portion 242 on the bus bar plate 24, and the bundling portion 93 of the plurality of voltage detection lines 9 is housed in the voltage detection line housing portion 244, it is possible to avoid the voltage detection line housing portion 244 from protruding upward, and to reduce the height of the battery module 1.

The above embodiment can be modified and improved as appropriate. For example, although the sensor projecting portion 731a is provided in the housing 73 of the sensor device 7 in the above embodiment, the electronic component 72 itself mounted on the board 71 may be provided as the sensor projecting portion. In the above embodiment, the high-level portion 242 and the low-level portion 243 are formed by the bus bar plate 24, but the high-level portion and the low-level portion may be formed by members other than the bus bar plate 24 as long as they are components of the cell stack 2.

[ 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,

the sensor device is provided with a sensor projection part (sensor projection part 731a) projecting downward,

a low portion (a low portion 243) that accommodates the sensor protruding portion is provided on the upper surface of the battery cell stack.

According to (1), the battery module is provided with the sensor device on the upper surface of the battery cell laminate, while the height dimension of the battery module can be suppressed by the nesting structure of the battery cell laminate and the sensor device.

(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 sensor bulge is arranged on the lower surface of the shell.

According to (2), the substrate and the electronic component are accommodated in the housing, so that the substrate and the like can be protected by the housing, and the height dimension can be reduced by the nested structure.

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

the electronic component is mounted on the lower surface of the substrate,

the sensor projection portion is an electronic component housing portion (electronic component housing portion 734) that houses the electronic component.

According to (3), only the outer wall of the electronic component housing portion having a required height is bulged to become the sensor bulging portion, and the sensor device can be downsized.

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

the lower portion is formed of a bus bar plate (bus bar plate 24) mounted on the upper surface of the cell stack.

According to (4), the height of the sensor projecting portion can be absorbed by the unevenness of the bus bar plate.

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

the bus bar plate includes a high portion (high portion 242) including terminal portions (terminal portions 92) of voltage detection lines (voltage detection lines 9) connected to a bus bar (bus bar 23), and the low portion provided between the terminal portions.

According to (5), although the terminal of the terminal portion of the voltage detection line is crimped to the wire, the height of the sensor bulging portion can be absorbed by the low portion of the terminal portion avoiding the voltage detection line.

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

a voltage detection line housing portion (voltage detection line housing portion 244) is provided in the bus bar plate, and houses the plurality of voltage detection lines at a position not overlapping the high position portion.

According to (6), the voltage detection line housing portion can be prevented from protruding upward.