JP2019016501A - Battery module - Google Patents

Abstract

To provide a battery module which can prevent a valve fragment and others jetted out from a gas-discharge unit from being scattered to the outside while avoiding an increase in size.SOLUTION: A battery module 1 comprises: a cell laminate 2 arranged by laminating a plurality of cells 21 in a front-back direction; a pair of end plates 3 disposed on front and rear faces of the cell laminate; and a fastening frame 4 for connecting the pair of end plates 3. On a top face of the cell laminate 2, gas-discharge parts 23 formed on top faces of respective cells 21 are provided. The fastening frame 4 includes a pair of side frames 5 disposed on right and left faces of the cell laminate 2. The pair of side frames 5 have side frame main bodies 51, and upper flange parts 53 extending along the top face of the cell laminate 2 in a direction in which they approach each other. The upper flange parts 53 cover the gas-discharge parts 23.SELECTED DRAWING: Figure 4

Description

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

  Conventionally, a battery module including a plurality of cells is mounted on an electric vehicle or the like. A typical cell has a bursting gas release valve to prevent the case from bursting when the internal pressure rises abnormally. When the internal pressure rises abnormally, the gas release valve bursts and the gas in the cell Is released to the outside (see, for example, Patent Document 1).

Japanese Patent No. 3969205

  However, when the gas release valve ruptures due to an abnormal increase in internal pressure, there is a possibility that fragments of the valve or high-temperature objects are ejected together with the gas and scattered outside the battery module. In the cell described in Patent Document 1, a shielding structure that prevents a high-temperature object from being ejected when the gas release valve ruptures is provided inside the cell. However, if a shielding structure is provided inside the cell, There is a possibility that the cell and the battery module are increased in size.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a battery module capable of preventing external scattering such as broken pieces of a valve ejected from a gas discharge portion while avoiding an increase in size. is there.

In order to achieve the above object, the invention described in claim 1
A cell stack (for example, a cell according to an embodiment described later) having a front surface, a rear surface, a left surface, a right surface, an upper surface, and a lower surface, which is configured by stacking a plurality of cells (for example, a cell 21 according to an embodiment described later) in the front-rear direction. Laminate 2),
A pair of end plates (for example, an end plate 3 in an embodiment described later) disposed on the front surface and the rear surface of the cell stack;
A battery module (e.g., a battery module 1 according to an embodiment described later) including a fastening frame (e.g., a fastening frame 4 according to an embodiment described later) for connecting the pair of end plates;
The upper surface of the cell stack is provided with a gas discharge portion (for example, a gas discharge portion 23 in an embodiment described later) formed on the top surface of each cell,
The fastening frame includes a pair of side frames (for example, a side frame 5 in an embodiment described later) disposed on the right side and the left side of the cell stack,
Each of the pair of side frames includes a side frame main body (for example, a side frame main body 51 in an embodiment described later) and an upper flange portion (for example, an embodiment described later) that extends in a direction approaching each other along the upper surface of the cell stack. An upper flange portion 53) of the form,
The upper flange portion covers the gas discharge portion.

The invention described in claim 2
The battery module according to claim 1,
An insulating member (for example, a fourth insulating member 9 in an embodiment described later) is provided between the upper surface of the cell stack and the upper flange portion.

The invention according to claim 3
The battery module according to claim 2,
The upper flange portion has elasticity,
The upper flange portion presses the insulating member toward the upper surface of the cell stack.

The invention according to claim 4
The battery module according to claim 2,
On the upper surface of the cell stack, a pair of terminal portions (for example, a terminal portion 22 in an embodiment described later) formed on the top surface of each cell is provided,
The gas discharge part is arranged outside in the left-right direction with respect to the pair of terminal parts,
The insulating member has a first partition wall (for example, a first partition wall 93 in an embodiment described later) that contacts the upper surface of the cell stack between the gas discharge unit and the terminal unit.

The invention described in claim 5
The battery module according to any one of claims 2 to 4,
The insulating member is positioned closer to the side frame body than the gas discharge part and is in contact with the upper surface of the cell stack (for example, a first partition part 93 in an embodiment described later). A second partition wall portion (for example, a second partition wall portion 94 in an embodiment described later) that is positioned in the front-rear direction across the gas discharge portion and that contacts the upper surface of the cell stack; A top plate portion (e.g., a top plate portion 95 in an embodiment described later) facing in the direction,
The gas discharge part is disposed in a gas discharge space (for example, a gas discharge space S1 in an embodiment described later) surrounded by the first partition part, the second partition part, and the top plate part.

The invention described in claim 6
The battery module according to claim 5,
The top plate portion of the insulating member has a vertical wall portion (for example, a vertical wall portion 96 in an embodiment described later) that extends downward toward the gas discharge portion and covers a part of the gas discharge portion. .

The invention described in claim 7
The battery module according to claim 5 or 6,
The insulating member extends in the front-rear direction so as to straddle a plurality of the cells,
In the second partition wall portion, a sheet end receiving groove (for example, later-described implementation) that accommodates an upper end portion of an insulating sheet (for example, a first insulating member 6 in an embodiment described later) provided between the adjacent cells. 94a) of the form is formed.

The invention according to claim 8 provides:
The battery module according to any one of claims 2 to 7,
Each of the pair of side frames further includes a lower flange portion (for example, a lower flange portion 54 in an embodiment described later) extending in a direction approaching each other along the lower surface of the cell stack,
The cell stack and the insulating member are sandwiched between the upper flange portion and the lower flange portion of the pair of side frames.

  According to the invention of claim 1, since the upper flange portion extending from the side frame main body covers the gas discharge portion of the cell, the fragment of the valve or the like ejected from the gas discharge portion is avoided in the battery module while avoiding an increase in size. It can be prevented from splashing outside.

  According to the second aspect of the present invention, since the insulating member is provided between the upper surface of the cell stack and the upper flange portion, the double-structured structure of the insulating member and the upper flange portion makes it possible to generate fragments of the valve. Can be reliably prevented.

  According to the invention of claim 3, since the upper flange portion presses the insulating member toward the upper surface of the cell stack, not only can the upper flange portion receive the momentum during scattering, but also the vibration resistance of the battery module. Can be improved.

  According to the invention of claim 4, since the insulating member has the first partition wall portion that contacts the upper surface of the cell stack between the gas discharge portion and the terminal portion, the fragments of the valve and the like scatter to the terminal side. This can be prevented by the first partition wall.

  According to invention of Claim 5, an insulating member has a 1st partition part, a 2nd partition part, and a top-plate part, and a gas discharge | release part consists of a 1st partition part, a 2nd partition part, and a top-plate part. Since it is arranged in the enclosed gas discharge space, it is possible to secure a discharge path for the gas discharged from the gas discharge portion.

  According to the invention of claim 6, the top plate portion of the insulating member extends downward toward the gas discharge portion, and has a vertical wall portion covering a part of the gas discharge portion, thereby suppressing deformation of the insulating member. As a result, it is possible to prevent the gas from being discharged and to prevent the fragments of the valve from being scattered.

  According to invention of Claim 7, an insulating member is extended in the front-back direction so that it may straddle a plurality of cells, and the 2nd partition part accommodates the upper end part of the insulating sheet provided between adjacent cells. Since the sheet end receiving groove is formed, the insulating member can be integrally formed to reduce the number of parts, and interference between the insulating member and the upper end portion of the insulating sheet can be prevented.

  According to invention of Claim 8, a pair of side frame further has a lower flange part extended in the direction which mutually approaches along the lower surface of a cell laminated body, respectively, and an upper flange part and a lower flange part of a pair of side frame, Thus, since the cell stack and the insulating member are sandwiched, even if gas is ejected from the gas discharge portion, the relative position fluctuation in the vertical direction of the cell stack and the insulating member can be regulated.

It is the perspective view which looked at the battery module which concerns on one Embodiment of this invention from diagonally upward. It is a disassembled perspective view of the battery module of FIG. It is a perspective view which shows the cell of the battery module of FIG. It is a top view of the battery module of FIG. It is the sectional view on the AA line of FIG. FIG. 6 is an enlarged view of a portion C in FIG. 5. It is the DD sectional view taken on the line of FIG. It is the figure of the cell and insulation member seen from the X direction of FIG. It is the figure of the cell and insulation member seen from the Y direction of FIG.

  Hereinafter, an embodiment of a battery module of the present invention will be described with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.

  As shown in FIG. 1 to FIG. 6, the battery module 1 according to the present embodiment is configured by stacking a plurality of cells 21 in the front-rear direction, and has a front surface, a rear surface, a left surface, a right surface, an upper surface, and a lower surface. A body 2, a pair of end plates 3 disposed on the front surface and the rear surface of the cell stack 2, and a fastening frame 4 that couples the pair of end plates 3. The fastening frame 4 of the present embodiment includes a pair of side frames 5 disposed on the left and right surfaces of the cell stack 2, but is disposed not only on the pair of side frames 5 but also on the bottom surface of the cell stack 2. A lower frame or the like may be provided.

  In this specification and the like, the stacking direction of the cells 21 is defined as the front-rear direction and the directions orthogonal to the stacking direction of the cells 21 are defined as the left-right direction and the up-down direction for the sake of simplicity and clarity. This is independent of the front-rear direction of the 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 cells 21 may coincide with the vehicle front-rear direction, may be the vehicle vertical direction, or the left-right direction, and is inclined from these directions. It may be a direction. In the drawing, the front of the battery module 1 is indicated as Fr, the rear as Rr, the left as L, the right as R, the upper as U, and the lower as D.

(Cell laminate)
The cell stack 2 is configured by alternately stacking a plurality of cells 21 and a plurality of first insulating members 6 in the front-rear direction. A pair of end plates 3 are disposed on the front and rear surfaces of the cell stack 2 in a state of insulation via the second insulating member 7, and a third insulating member 8 is disposed on the lower surface of the cell stack 2. . In addition, a pair of side frames 5 are disposed on the left and right surfaces of the cell stack 2 in an insulated state with a slight gap therebetween. On the upper surface of the cell stack 2, a pair of fourth insulating members 9 are disposed at the left end and the right end.

  As shown in FIG. 3, on the upper surface of the cell stack 2, a pair of terminal portions 22 formed on the top surface of each cell 21, and a gas disposed outside in the left-right direction from the pair of terminal portions 22. And a discharge portion 23. The pair of terminal portions 22 includes a plus terminal and a minus terminal. The plus terminal is connected to the minus terminal of the adjacent cell 21 via a bus bar (not shown), and the minus terminal is connected to the plus of the adjacent cell 21 with a bus bar ( The plurality of cells 21 are electrically connected in series by being connected via a not-shown). The cell stack 2 of the present embodiment is configured by stacking a plurality of cells 21 so that the horizontal direction is alternately reversed in order to shorten the length of the bus bar.

  The gas discharge unit 23 includes a bursting type valve in order to prevent the case from bursting when the internal pressure of the cell 21 abnormally increases. When the internal pressure of the cell 21 rises abnormally, the valve of the gas discharge part 23 is ruptured and the gas in the cell 21 is released to the outside. However, there is a possibility that a fragment of the valve or a high-temperature object is ejected together with the gas. As described above, since the cell stack 2 of the present embodiment is configured by stacking a plurality of cells 21 so that the directions in the left-right direction are alternately reversed, the gas discharge portion 23 of each cell 21 has a cell stack. It arrange | positions in the state distributed to the right-and-left end part in the upper surface of the body 2.

(end plate)
The pair of end plates 3 are in contact with the front and rear surfaces of the cell stack 2 via the second insulating member 7, respectively, and receive the load in the cell stack direction of the cell stack 2. The load in the cell stacking direction of the cell stack 2 is mainly caused by expansion of the cell 21 due to temperature change or aging deterioration. The end plate 3 of the present embodiment is formed using, for example, an aluminum extruded material, and is provided on the end plate main body 31 along the front surface of the cell laminate 2 and the left and right end portions of the end plate main body 31, and the bolt B is A side frame fixing portion 32 to which the side frame 5 is fixed, and a left and right end portions of the end plate body 31 are formed so as to penetrate in the vertical direction, and are fixed to a structure (such as a vehicle body) that supports the battery module 1. And a structure fixing portion 33 that is fixed via (not shown).

(Side frame)
The pair of side frames 5 are formed by pressing a metal plate material. The side frame body 51 extends along the left surface or the right surface of the cell stack 2, and the front surface of the side frame body 51 from the front end to the front end plate 3. A front flange portion 52F extending in a direction approaching each other along the rear side, a rear flange portion 52R extending in a direction approaching each other along the rear surface of the rear end plate 3 from the rear end of the side frame main body 51, and an upper end of the side frame main body 51 The upper flange part 53 extended in the direction which mutually approaches along the upper surface of the cell laminated body 2, and the lower flange part 54 extended in the direction which mutually approaches along the lower surface of the cell laminated body 2 from the lower end of the side frame main body 51 are provided.

  The front flange portion 52F and the rear flange portion 52R are provided with a plurality of fastening portions 52a that are fastened to the front end plate 3 or the side frame fixing portion 32 of the rear end plate 3 via bolts B. The fastening portion 52a has a round hole through which the bolt B is inserted, and the bolt B inserted through the round hole is screwed into the front end plate 3 or the side frame fixing portion 32 of the rear end plate 3, thereby The flange portion 52F and the rear flange portion 52R are fastened to the front end plate 3 or the rear end plate 3.

  The upper flange portion 53 is disposed so as to cover the gas discharge portion 23 of the cell 21 as viewed from above. According to such an upper flange portion 53, it is possible to prevent the fragments of the valve ejected from the gas discharge portion 23 from being scattered outside the battery module 1.

  Further, a fourth insulating member 9 is provided between the upper flange portion 53 and the upper surface of the cell stack 2. For this reason, the double structure of the fourth insulating member 9 and the upper flange portion 53 can more reliably prevent external scattering such as valve fragments.

  Further, the upper flange portion 53 has elasticity and presses the fourth insulating member 9 toward the upper surface of the cell stack 2. If it does in this way, not only can it receive the momentum at the time of scattering by the upper flange part 53, but the vibration resistance of the battery module 1 can be improved.

  The upper flange portion 53 of the present embodiment is composed of a plurality of elastic pieces 53a arranged in the front-rear direction, and the number and positions of the elastic pieces 53a correspond to the number and positions of the cells 21 stacked in the front-rear direction. Yes. Thereby, the upper flange portion 53 can press the fourth insulating member 9 toward the upper surface of the cell stack 2 while covering the gas discharge portion 23 of the cell 21 from above.

  In the side frame 5 of the present embodiment, the upper flange portion 53 is press-molded integrally with the side frame main body 51. However, after the upper flange portion 53 is press-molded separately from the side frame main body 51, welding or You may integrate with the side frame main body 51 by caulking.

  The upper flange portion 53 and the lower flange portion 54 sandwich the fourth insulating member 9 and the cell stack 2 from above and below at the left end and the right end of the cell stack 2. Thereby, even if gas etc. eject from the gas discharge part 23, the relative position fluctuation | variation of the up-down direction of the cell laminated body 2 and the 4th insulating member 9 can be controlled.

(Fourth insulation member)
Next, the fourth insulating member 9 will be described in detail with reference to FIGS. 4 to 8B.

  The fourth insulating member 9 extends in the front-rear direction so as to straddle the plurality of cells 21, and includes an upper surface insulating portion 91 disposed along both the left and right upper surfaces of the cell stacked body 2, and the cell stacked body 2. And a side insulating part 92 disposed along the upper end of the side. The upper surface insulating portion 91 maintains an insulation state between the upper flange portion 53 of the side frame 5 and the cell stack 2, and the side surface insulating portion 92 is formed between the side frame body 51 of the side frame 5 and the cell stack 2. The insulation state between them is maintained.

  The upper surface insulating portion 91 is positioned on the side farther from the side frame body 51 than the gas discharge portion 23 and is positioned in the front-rear direction across the gas discharge portion 23 with the first partition wall portion 93 contacting the upper surface of the cell stack 2. A second partition wall portion 94 that is in contact with the upper surface of the cell stack 2, a top plate portion 95 that faces the gas discharge portion 23 in the vertical direction, and extends downward from the top plate portion 95 toward the gas discharge portion 23. And a vertical wall portion 96 covering a part of the gas discharge portion 23. A gas discharge space S1 surrounded by the first partition wall portion 93, the second partition wall portion 94, and the top plate portion 95 is formed on the lower surface of the upper surface insulating portion 91, and the gas discharge portion 23 faces the gas discharge space S1. Arranged to release gas. The gas discharged into the gas discharge space S1 is discharged to the outside of the battery module 1 through the discharge space S2 formed between the left and right outer ends of the second partition wall portion 94 and the side surface insulating portion 92. The

  According to such a fourth insulating member 9, it is possible to ensure that a gas discharge path of the gas discharged from the gas discharge portion 23 is scattered outside the battery module 1, such as a fragment of a valve that is jetted together with the gas. Can be prevented. Further, as shown in FIG. 7, since the fourth insulating member 9 has a vertical wall portion 96 that covers a part of the gas discharge portion 23, deformation of the top plate portion 95 is suppressed, so that gas can be discharged. At the same time, it is possible to prevent scattering of valve fragments and the like. Further, the first partition wall portion 93 is in contact with the upper surface of the cell stack 2 between the gas discharge portion 23 and the terminal portion 22, thereby preventing the fragments of the valve and the like from being scattered to the terminal portion 22 side. .

  Further, as shown in FIG. 8A, a sheet end receiving groove 94a for storing the upper end portion of the sheet-like first insulating member 6 provided between the adjacent cells 21 is formed on the lower surface portion of the second partition wall portion 94. Is provided. Thereby, interference of the 4th insulating member 9 and the upper end part of the 1st insulating member 6 can be prevented, enabling integral formation of the 4th insulating member 9 straddling the some cell 21. FIG.

  As described above, according to the battery module 1 of the present embodiment, the upper flange portion 53 extending from the side frame main body 51 covers the gas discharge portion 23 of the cell 21, so that the gas discharge is avoided while avoiding an increase in size. It is possible to prevent the fragments of the valve ejected from the portion 23 from being scattered outside the battery module 1.

  In addition, since the fourth insulating member 9 is provided between the upper surface of the cell stack 2 and the upper flange portion 53, the double structure of the fourth insulating member 9 and the upper flange portion 53 allows the valve to be It is possible to more surely prevent scattering of debris.

  Moreover, since the upper flange portion 53 presses the fourth insulating member 9 toward the upper surface of the cell stack 2, not only can the upper flange portion 53 receive the momentum during scattering, but also the vibration resistance of the battery module 1. Can be improved.

  Moreover, since the 4th insulating member 9 has the 1st partition part 93 contact | abutted on the upper surface of the cell laminated body 2 between the gas discharge | release part 23 and the terminal part 22, the fragment of a valve etc. to the terminal part 22 side It is possible to prevent the first partition wall portion 93 from scattering.

  The fourth insulating member 9 includes a first partition wall portion 93, a second partition wall portion 94, and a top plate portion 95, and the gas discharge portion 23 includes the first partition wall portion 93, the second partition wall portion 94, and the top plate portion. 95, the gas discharge path (discharge space S2) of the gas discharged from the gas discharge portion 23 can be easily secured.

  In addition, since the cell stack 2 and the fourth insulating member 9 are sandwiched between the upper flange portion 53 and the lower flange portion 54 of the side frame 5, even if gas is ejected from the gas discharge portion 23, the cell The relative position fluctuation in the vertical direction between the stacked body 2 and the fourth insulating member 9 can be restricted.

  Moreover, since the top-plate part 95 of the 4th insulating member 9 is extended below toward the gas discharge part 23, and a deformation | transformation is suppressed by having the vertical wall part 96 which covers a part of gas discharge part 23, it is. , While allowing gas to be discharged, it is possible to prevent scattering of valve fragments and the like.

  In addition, the second partition wall portion 94 is formed with a sheet end receiving groove 94a for receiving the upper end portion of the first insulating member 6 provided between the adjacent cells 21, so that the second partition wall 94 extends across the plurality of cells 21. Interference between the fourth insulating member 9 and the upper end portion of the first insulating member 6 can be prevented while enabling the four insulating members 9 to be integrally formed.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

DESCRIPTION OF SYMBOLS 1 Battery module 2 Cell laminated body 21 Cell 22 Terminal part 23 Gas discharge part 3 End plate 4 Fastening frame 5 Side frame 51 Side frame main body 53 Upper flange part 54 Lower flange part 6 1st insulation member (insulation sheet)
9 Fourth insulation member (insulation member)
93 1st partition part 94 2nd partition part 94a Sheet end accommodation groove 95 Top plate part 96 Vertical wall part S1 Gas discharge space

Claims (8)

A cell stack comprising a plurality of cells stacked in the front-rear direction, 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 disposed on the front and rear surfaces of the cell stack;
A fastening frame for connecting the pair of end plates, and a battery module comprising:
The upper surface of the cell stack is provided with a gas discharge portion formed on the top surface of each cell,
The fastening frame includes a pair of side frames disposed on the right side and the left side of the cell stack,
Each of the pair of side frames includes a side frame main body and an upper flange portion extending in a direction approaching each other along the upper surface of the cell stack,
The upper flange portion covers the gas discharge portion. The battery module according to claim 1,
A battery module in which an insulating member is provided between the upper surface of the cell stack and the upper flange portion. The battery module according to claim 2,
The upper flange portion has elasticity,
The upper flange portion is a battery module that presses the insulating member toward the upper surface of the cell stack. The battery module according to claim 2,
On the upper surface of the cell stack, a pair of terminal portions formed on the top surface of each cell is provided,
The gas discharge part is arranged outside in the left-right direction with respect to the pair of terminal parts,
The said insulating member is a battery module which has a 1st partition part contact | abutted to the said upper surface of the said cell laminated body between the said gas discharge part and the said terminal part. The battery module according to any one of claims 2 to 4,
The insulating member is positioned on a side farther from the side frame body than the gas discharge portion, and is positioned in the front-rear direction across the gas discharge portion, and a first partition wall portion that contacts the upper surface of the cell stack. A second partition wall portion in contact with the upper surface of the cell stack, and a top plate portion facing the gas discharge portion in the vertical direction,
The said gas discharge | release part is a battery module arrange | positioned in the gas discharge | release space enclosed by the said 1st partition part, the said 2nd partition part, and the said top-plate part. The battery module according to claim 5,
The said top plate part of the said insulating member is a battery module which has a vertical wall part extended below toward the said gas discharge | release part, and covering a part of said gas discharge | release part. The battery module according to claim 5 or 6,
The insulating member extends in the front-rear direction so as to straddle a plurality of the cells,
The battery module in which the 2nd partition part is formed with the sheet end accommodation slot which accommodates the upper end part of the insulating sheet provided between the adjacent cells. The battery module according to any one of claims 2 to 7,
Each of the pair of side frames further includes a lower flange portion extending in a direction approaching each other along the lower surface of the cell stack,
The battery module, wherein the cell stack and the insulating member are sandwiched between the upper flange portion and the lower flange portion of the pair of side frames.

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