CN212991193U

CN212991193U - End plate for battery module and battery module

Info

Publication number: CN212991193U
Application number: CN202021962874.2U
Authority: CN
Inventors: 关俊山; 肖康; 王进军; 杜肖源; 郭其鑫; 曹勇
Original assignee: China Aviation Lithium Battery Co Ltd; China Aviation Lithium Battery Research Institute Co Ltd
Current assignee: Avic Innovation Technology Research Institute Jiangsu Co ltd; China Aviation Lithium Battery Co Ltd; China Lithium Battery Technology Co Ltd
Priority date: 2020-09-09
Filing date: 2020-09-09
Publication date: 2021-04-16
Anticipated expiration: 2030-09-09

Abstract

The application relates to the field of batteries and discloses an end plate for a battery module and the battery module. This end plate for battery module includes: the end plate body is equipped with at least one fixed orifices, follows the direction of height of end plate body, the fixed orifices link up the top surface and the bottom surface of end plate body, just end plate thickness direction, the center of fixed orifices with the distance of the surface of end plate body is less than the center of fixed orifices with the distance of the internal surface of end plate body. The end plate is used for solving the problem that the insulating film of the battery with a fixed structure is easy to wear in the prior art.

Description

End plate for battery module and battery module

Technical Field

The application relates to the field of batteries, in particular to an end plate for a battery module and the battery module.

Background

The battery module generally includes an end plate, a side plate, and a battery pack, and when the battery module is fixed to a case of a battery pack, the end plate and the case are required to be fixed. A fixing hole is generally provided on the end plate to be connected with the housing. The end plate is divided into an inner surface and an outer surface in a thickness direction, wherein the inner surface is disposed facing the battery pack, and the outer surface is located on a side away from the battery pack. The fixing hole is generally provided at a middle portion between the inner surface and the outer surface to perform a fixing connection function. The inventors have found that when fixing structures such as bolts and rivets are inserted through the fixing holes to fixedly connect the battery module and the pack case, the battery is worn out and even the insulating film is damaged, causing a safety problem.

Disclosure of Invention

The application discloses end plate and battery module for solve the problem of fixed knot structure easy wearing and tearing battery among the prior art.

In order to achieve the purpose, the application provides the following technical scheme:

in a first aspect, the present application provides an end plate for a battery module, comprising: the battery module comprises an end plate body, wherein when the end plate is fixed on the battery module, the height direction of the end plate body is the height direction of the battery module, and the thickness direction of the end plate body is the arrangement direction of single batteries in the battery module; the end plate body is equipped with at least one fixed orifices the direction of height of end plate body, the fixed orifices link up the top surface and the bottom surface of end plate body, and be in the thickness direction of end plate, the fixed orifices is close to the surface of end plate body.

The application provides an end plate for battery module, when setting up the fixed orifices, through setting up the fixed orifices in the one side of being close to keeping away from the group battery, set up in the one side of being close to end plate body surface promptly, can increase the clearance between the fixed knot who wears to establish the fixed orifices and the group battery under the condition that does not change apron thickness, be difficult for damaging the battery.

In a second aspect, the present application provides a battery module including the end plate of the first aspect of the present application.

Because this battery module contains the end plate of this application, consequently, among the battery module of this application, the difficult quilt of battery insulating film is destroyed, has the good advantage of electrical insulation stability.

Drawings

Fig. 1 is a schematic structural diagram of a battery module according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of an end plate according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of an end plate body and a flange after being bolted according to an embodiment of the present disclosure;

FIG. 4 is an enlarged schematic view of the structure at A in FIG. 2;

fig. 5 is a schematic structural diagram of an inner surface side of an end plate according to an embodiment of the present application;

fig. 6 is a schematic top view of an end plate according to an embodiment of the present disclosure.

Reference numerals: 1-an end plate; 101-an outer surface; 102-an inner surface; 103-side; 11-a fixation hole; 12-a welding groove; 121-cell wall; 13-a notch; 14-arc surface; 15-a cavity; 16-hoisting holes; 17-a positioning groove; 2-side plate; 21-side plate body; 22-side plate folding lug; 3-a battery pack; 4-cover plate; 5-flange bolts.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In order to more clearly explain the positional relationship of the end plates in the battery module and the relative arrangement of the respective faces, the structure of the battery module including the end plates will be described first.

Fig. 1 is a schematic structural view of a battery module according to an embodiment of the present invention, and as shown in fig. 1, the battery module according to the embodiment of the present invention includes an end plate 1, a side plate 2, a battery pack 3, and a cover plate 4. The number of the end plates 1 is two, and the number of the side plates 2 is also two. Two end plate 1 set up relatively, and two curb plates 2 set up relatively, the both ends of an end plate 1 respectively with the one end fixed connection of two curb plates 2, the both ends of another end plate 1 respectively with the other end fixed connection of two curb plates 2, form the chamber that holds that is used for holding group battery 3. The lid plate 4 is disposed above the battery pack 3 for enclosing the battery pack 3. The battery pack 3 includes a plurality of unit cells arranged side by side. Here, for convenience of understanding, the height direction of the end plate is defined as the Z-axis direction shown in fig. 1, the width direction of the end plate is the X-axis direction shown in fig. 1, and the thickness direction of the end plate is the Y-axis direction shown in fig. 1.

In one embodiment of the present application, as shown in fig. 2, the end plate 1 includes an end plate body 10, and when the end plate 1 is fixed to the battery module, the height direction of the end plate body 10 is the height direction of the battery module, i.e., the Z-axis direction shown in fig. 1, and the thickness direction of the end plate body 10 is the arrangement direction of the unit cells in the battery module, i.e., the Y-axis direction shown in fig. 1.

The surface of the end plate body 10 on the side facing the battery pack 3 is an inner surface 102, and the surface of the end plate body 10 on the side facing away from the battery pack 3 is an outer surface 101. Referring to fig. 1 and 2 together, in a height direction of the end plate body 10, such as a Z-axis direction shown in fig. 1, the end plate body 10 is divided into a top surface and a bottom surface; in a width direction of the end plate body 10, as shown in an X-axis direction in fig. 1, the end plate body 10 includes two oppositely disposed side surfaces 103. The end plate body 10 is provided with at least one fixing hole 11, and the number of the fixing holes 11 may be, for example, one, two, three, or the like. The fixing hole 11 is provided between the outer surface 101 and the inner surface 102, and penetrates the top surface and the bottom surface of the endplate body 10 in the height direction of the endplate body 10. When the fixing hole 11 is provided, the fixing hole 11 is provided near the outer surface 101 of the end plate body 10, and in this case, the distance between the center of the fixing hole 11 and the outer surface 101 of the end plate body 10 is smaller than the distance between the center of the fixing hole 11 and the inner surface 102 of the end plate body 10.

The application provides an end plate 1 for battery module, when setting up fixed orifices 11, through setting up fixed orifices 11 in the one side of being close to keeping away from group battery 3, set up in the one side of being close to end plate body 10 surface 101 promptly, can be under the condition that does not change apron 4 thickness, use fixed knot structure as the flange bolt as an example, increase the clearance between flange portion and the group battery 3 of flange bolt, when mounting flange bolt, a sleeve for rotating the flange bolt is difficult for damaging the battery insulation film yet.

Wherein, the fixing hole 11 may be a cylindrical through hole. When the number of the fixing holes 11 is two, the two fixing holes 11 are oppositely disposed along the width direction of the end plate body 10, and in the width direction of the end plate body 10, the two fixing holes 11 are respectively disposed near the corresponding side surfaces 103, for example, the corresponding two side surfaces 103 are respectively marked as a first side surface and a second side surface, wherein the distance between one fixing hole 11 and the first side surface is greater than the distance between the fixing hole 11 and the second side surface, and the distance between the other fixing hole 11 and the first side surface is less than the distance between the fixing hole 11 and the second side surface.

In an embodiment of the present application, in the thickness direction of the end plate body, a first distance is provided between the hole wall of the fixing hole and the outer surface of the end plate body. The first distance may be such that an edge of the fixation structure does not extend beyond an outer surface of the endplate body after the fixation structure is assembled within the fixation hole. As shown in fig. 3, taking the fixing structure as the flange bolt 5 as an example, in this case, in the thickness direction of the end plate body 10, the edge of the flange portion of the flange bolt 5 for fitting connection with the fixing hole 11 is located between the hole wall of the fixing hole 11 and the outer surface. Thus, the flange portion and the top surface of the end plate body 10 can maintain the original contact area, and the torque can be prevented from being reduced. When the battery pack 3 expands, the flange part of the flange bolt can keep a certain gap with the battery pack 3, the risk that the flange part wears a battery insulating film is reduced, and the battery module is enabled to keep good electrical insulation performance all the time.

In an embodiment of the application, after the flange bolts are assembled in the fixing holes, in the thickness direction of the end plate body, the distance from the edge of the flange part to the outer surface is greater than or equal to 0.5-1.5mm, so that the flange part can be always in contact with the top surface of the end plate body, and torque reduction can be effectively avoided.

In an embodiment of the present application, referring to fig. 2, a side of the end plate body 10 away from the battery pack 3, i.e., an outer surface 101 of the end plate body 10, is provided with at least two welding grooves 12 for welding the side plates 2, and the welding grooves 12 are used for welding the side plate lugs 22 of the side plates 2. Referring to fig. 1 and 2 together, the side plate 2 includes a side plate body 21 and a side plate folded lug 22 bent from the side plate body 21, and the side plate folded lug 22 is welded in the welding groove 12. Referring to fig. 1, each side plate 2 is provided with a side plate folded lug 22, the side plate folded lug 22 is disposed in the welding groove 12, for example, the side plate folded lug 22 can be welded in the welding groove 12 by a laser welding process, and the side plate body 21 can be attached to the side surface 103 of the end plate body 10.

Referring to fig. 2, two welding grooves 12 are formed on an outer surface 101 of each end plate body 10, and the two welding grooves 12 are oppositely disposed in a width direction of the end plate body 10 and are disposed near a side surface 103 of the end plate body to facilitate welding of the side plate lugs 22. In addition, when the welding grooves 12 are provided, the number of the welding grooves 12 may be adjusted according to the number of the side plate lugs 22, so that the welding grooves 12 and the side plate lugs 22 are engaged with each other.

As shown in fig. 4, in one embodiment of the present application, the welding groove 12 is formed recessed inward from the outer surface 101 in the thickness direction of the end plate body 10.

In one embodiment of the present application, the welding groove 12 has a U-shaped structure, and the opening direction thereof faces the direction of the side surface 103. The welding groove 12 is of a U-shaped structure, and at this time, in the height direction of the end plate body 10, the groove wall 121 of the welding groove 12 is located between the top surface and the bottom surface of the end plate body 10, so that a sufficient distance can be left between the fixing hole and the outer surface 101 on the top surface of the end plate body 10 to ensure that the flange portion of the flange bolt is in contact with the top surface, and the flange portion is prevented from being suspended. Meanwhile, the welding groove is of a U-shaped structure, and the fixing hole 11 can be conveniently formed, so that the thickness of the end plate body 10 is prevented from being increased. The welding groove of this structure can be machined into the welding groove 12 on the surface of the end plate body 10 by machining after the end plate body 10 is molded.

In addition, the welding groove 12 is configured to be U-shaped, and the opening direction of the welding groove is toward the side surface 103, so that the side plate folded lug 22 can be conveniently placed in the welding groove 12, and the end surface of the side plate folded lug 22 facing the free end of the welding groove 12 is of a planar structure, so that the side plate folded lug can be conveniently assembled with the groove wall 121 of the welding groove 12.

With continued reference to fig. 4, the groove wall 121 of the weld groove 12 for abutment with the side plate lugs 22 is perpendicular to the groove bottom. Because the end of the side plate lug is generally in a plane structure, at the moment, the groove wall 121 of the welding groove 12 is vertically arranged with the groove bottom, so that the end surface of the side plate lug 22 can be ensured to be in close contact with the welding groove 12, and the gap of a welding seam is eliminated. Meanwhile, the vertical arrangement structure of the groove wall can also ensure that the welding line has effective fusion width and fusion depth in the laser welding process, and the welding line strength is improved.

In one embodiment of the present application, the distance between the bottom of the welding groove and the wall of the fixing hole in the thickness direction of the end plate body 10 is 1 to 3 mm. The setting of this distance can effectively guarantee the structural strength of fixed orifices.

With continued reference to fig. 4, in an embodiment of the present application, at the opening of the welding groove 12, a circular arc surface 14 is formed between the groove bottom of the welding groove 12 and the side surface 103 of the end plate body 10, wherein the side surface 103 of the end plate body 10 is used for connecting the side plate body 21. Through setting up arc surface 14 to guarantee the assembly interface smooth transition between welding groove 12 and the curb plate body 21, avoid this position to produce stress concentration phenomenon, prevent that curb plate 2 from breaking down under the effect of battery expansion power, improve the reliability of battery module structure.

It can be understood that, the side of the connecting portion of the side plate body 21 and the side plate folded lug 22 facing the end plate 1 is also provided with the arc surface 14, when the battery pack 3 expands during the charge and discharge cycle, the expansion force generated by the battery pack 3 acts on the end plate 1 and the side plate 2. At this time, the arc surface 14 is provided at the connecting portion of the side plate body 21 and the side plate bent lug 22, so that the stress concentration phenomenon of the expansion force at the side plate 2 can be avoided.

In one embodiment of the present application, the radius of the circular arc surface 14 is equal to or greater than 7 mm. When the radius of the arc surface 14 is greater than or equal to 7mm, the problem of stress concentration of the expansion force of the battery pack 3 on the side plate 2 can be effectively solved, and the reliability of the battery module structure is improved; and simultaneously, the processing and the manufacturing of the arc surface 14 are convenient.

Fig. 5 is a schematic structural view of an end plate 1 according to an embodiment of the present application, and fig. 6 is a schematic structural view of a top view of the end plate 1 according to an embodiment of the present application. Referring to fig. 5 and 6 together, a notch 13 is provided at the intersection of the inner surface 102 of the end plate body 10 and the side surface 103 of the end plate body 10, and the notch 13 can form a glue overflow space. When assembling the battery module, need the coating gluing agent between group battery 3 and end plate 1, coating gluing agent simultaneously between group battery 3 and curb plate 2 to with group battery 3 and

end plate

1 and 2 fixed connection of curb plate. Certain acting force can be exerted between end plate 1 and group battery 3 after the coating gluing agent to and curb plate 2 and group battery 3, and at this moment, unnecessary gluing agent can spill over. Set up breach 13 in the crossing department of the internal surface 102 of end plate body 10 and side 103, can make the gluing agent of end plate 1 department and the gluing agent of curb plate 2 department flow in this breach 13 department simultaneously, the clear process of gluing in reducible later stage improves the assembly efficiency of module.

As shown in fig. 6, in an embodiment of the present application, the notch 13 penetrates through the top and bottom surfaces of the endplate body 10 in the height direction of the endplate body 10. Through setting up breach 13 that link up, more make things convenient for the gluing agent on end plate body 10 and the curb plate body 21 to get into in this sol space.

As shown in fig. 6, a cavity 15 is formed in the end plate body 10, the cavity 15 is rectangular, the cavity 15 extends in the height direction of the end plate body 10, and a lifting hole 16 is formed in a position, corresponding to the cavity 15, of the outer surface 101 of the end plate body 10, and is used for transferring and assembling the battery module. The section of the cavity 15 is rectangular, the length-width ratio is less than or equal to 1.2, a hoisting hole can be conveniently machined, and meanwhile, the structural strength of the end plate body 10 can meet the use requirement.

In addition, in an embodiment of the present application, as shown in fig. 5, the end plate 1 is provided with a positioning groove 17, the positioning groove 17 is used for installing a protective support of the battery module, and a conductive member led out from the battery pack 3 is arranged in the protective support. The positioning slot 17 can play a role in mounting and limiting the protective support. With continued reference to fig. 5, the positioning groove 17 is disposed on the top of the end plate body and is a slot opening toward the battery pack, and when the protection support is installed, the protection support can be clamped in the positioning groove 17.

In the end plate 1 of an embodiment of the present application, the edges of the inner surface 102 of the end plate 1 may be provided with rounded corners, and the radius R of the rounded corners is, for example, R ≦ 3 mm. Can prevent the edge wearing and tearing battery insulation film of end plate 1 through setting up the fillet to effectively avoided under the operating mode states such as extrusion, impact the risk that end plate 1 crushes group battery 3.

It will be apparent to those skilled in the art that various changes and modifications may be made in the embodiments of the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. An end plate for a battery module, comprising: the end plate body is provided with a plurality of end plates,

when the end plate is fixed on the battery module, the height direction of the end plate body is the height direction of the battery module, and the thickness direction of the end plate body is the arrangement direction of single batteries in the battery module;

the end plate body is equipped with at least one fixed orifices the direction of height of end plate body, the fixed orifices link up the top surface and the bottom surface of end plate body, and end plate thickness direction, the center of fixed orifices with the distance of the surface of end plate body is less than the center of fixed orifices with the distance of the internal surface of end plate body.

2. The end plate according to claim 1, wherein a first distance is provided between a hole wall of the fixing hole and an outer surface of the end plate body in a thickness direction of the end plate body.

3. The end plate according to claim 2, wherein a distance from an edge of the fixing structure to the outer surface in a thickness direction of the end plate body is 0.5 to 1.5mm or more when the fixing structure is fitted in the fixing hole.

4. An end plate according to any of claims 1-3, wherein the outer surface of the end plate body is provided with at least two welding grooves;

the welding groove is used for being welded with the side plate folding lug of the battery module side plate.

5. The end plate of claim 4, wherein a groove wall of the weld groove is between the top surface and the bottom surface of the end plate body in a height direction of the end plate body.

6. The end plate according to claim 4, wherein a distance between a groove bottom of the welding groove and a wall of the fixing hole in a thickness direction of the end plate body is 1 to 3 mm.

7. The end plate according to claim 4, wherein the end plate body includes two side surfaces oppositely arranged in a width direction of the end plate body, and a circular arc surface is provided between a groove bottom of the welding groove and the side surfaces; the radius of the arc surface is more than or equal to 7 mm.

8. The end plate according to any one of claims 1 to 3, wherein the end plate body includes an inner surface disposed opposite to the outer surface in a thickness direction of the end plate body, and two side surfaces disposed opposite to each other in a width direction of the end plate body;

wherein, a gap is arranged at the intersection of the inner surface and the side surface to form a glue overflowing space; in the height direction of the end plate body, the notch penetrates through the top surface and the bottom surface of the end plate body.

9. A battery module, comprising: the end plate of any of claims 1-8.

10. The battery module according to claim 9, further comprising a side plate and a battery pack;

the end plates are fixedly connected with the side plates to form accommodating cavities for accommodating the battery packs; the battery pack is located in the accommodating cavity.