CN217444543U

CN217444543U - Battery pack

Info

Publication number: CN217444543U
Application number: CN202220635062.XU
Authority: CN
Inventors: 梁绍泽; 陈伟东; 王辉煌; 陈小源; 廖桂珍
Original assignee: Sunwoda Electric Vehicle Battery Co Ltd
Current assignee: Xinwangda Power Technology Co ltd
Priority date: 2022-03-22
Filing date: 2022-03-22
Publication date: 2022-09-16
Anticipated expiration: 2032-03-22

Abstract

The application discloses battery package includes: the battery box comprises a box body and a plurality of battery modules, wherein the box body comprises a top cover and a bottom shell, the bottom shell is provided with an accommodating groove, one side of the accommodating groove is provided with an opening, the top cover is connected to the bottom shell at the opening and covers the opening, the accommodating groove and the top cover define an accommodating cavity, the top cover comprises an upper shell and a fireproof piece, the fireproof piece is positioned on one side of the upper shell, which faces the accommodating cavity, and a heat insulation cavity is formed between the fireproof piece and the upper shell; the battery module sets up in holding the intracavity, and the battery module includes a plurality of electric cores, and each electric core has explosion-proof valve, and explosion-proof valve is towards thermal-insulated chamber. The heat insulation cavity between the fireproof piece and the upper shell slows down the time of heat transfer to the upper shell. In addition, the fireproof part can be prevented from being transmitted to the upper shell due to the deformation caused by high temperature, so that the deformation degree of the upper shell is reduced, the upper shell is prevented from being burnt through, and the fire is prevented from spreading.

Description

Battery pack

Technical Field

The application relates to the technical field of batteries, in particular to a battery pack.

Background

With the development of the industry, the application of the battery is more and more extensive, and the requirement on the safety of the battery is higher and higher. However, the existing battery module generates high-temperature and high-pressure flame after the thermal runaway of the battery core, and the flame easily burns through the upper shell, so that the flame spreads.

SUMMERY OF THE UTILITY MODEL

The present application is directed to solving at least one of the problems in the prior art. Therefore, the application provides a battery pack which can slow down the fire spread.

A battery pack according to an embodiment of the present application includes: the battery pack comprises a box body and a plurality of battery modules, wherein the box body comprises a top cover and a bottom shell, the bottom shell is provided with a containing groove, one side of the containing groove is provided with an opening, the top cover is connected to the bottom shell at the opening and covers the opening, the containing groove and the top cover define a containing cavity, the top cover comprises an upper shell and a fireproof piece, the fireproof piece is positioned on one side of the upper shell, which faces the containing cavity, and a heat insulation cavity is arranged between the fireproof piece and the upper shell; the battery module sets up in holding the intracavity, the battery module includes a plurality of electric cores, each the electric core has explosion-proof valve, explosion-proof valve orientation thermal-insulated chamber.

According to the battery pack of the embodiment of the application, at least the following beneficial effects are achieved:

the top cover comprises an upper shell and a fireproof piece, and a heat insulation cavity is arranged between the fireproof piece and the upper shell. The battery module sets up in holding the intracavity, and the explosion-proof valve orientation fire prevention piece on the electric core of battery module. Therefore, when the battery core is out of control due to heat, high-temperature and high-pressure gas or flame can be sprayed out of the explosion-proof valve to burn the fireproof piece. Because of the fire prevention spare has thermal-insulated chamber with the epitheca, so can slow down the time of heat transfer to the epitheca, and can reduce epitheca heat altered shape degree to avoid the epitheca to burn through, prevent that the intensity of a fire from stretching to the outside of battery package box.

According to some embodiments of the present application, a support structure is further provided between the fire-proof member and the upper case for supporting the fire-proof member and the upper case.

According to some embodiments of the application, the upper shell and the fire-resistant member are connected by resistance welding.

According to some embodiments of the application, a surface of the fire-proof member facing away from the upper case is provided with a plurality of fire-proof portions, the fire-proof portions protrude from the surface of the fire-proof member facing away from the upper case, and each fire-proof portion is aligned with the explosion-proof valve of each battery cell respectively

According to some embodiments of the application, a plurality of the fire-proof pieces are connected to a surface of the upper case facing the accommodation cavity, and the fire-proof pieces are spaced apart from each other and aligned with the explosion-proof valve of each battery cell.

According to some embodiments of the application, the fire prevention member is detachably connected to the upper case.

According to some embodiments of the application, the bottom shell is provided with a first connecting portion towards one side of the upper shell, the upper shell has a second connecting portion towards one side of the bottom shell, the first connecting portion and the second connecting portion are detachably connected, a first positioning structure is arranged between the first connecting portion and the second connecting portion, and the first positioning structure is used for limiting the relative position of the upper shell and the bottom shell.

And a second positioning structure is arranged between the fireproof piece and the upper shell and is used for limiting the relative position of the fireproof piece and the upper shell.

According to some embodiments of the application, the upper shell and/or the fireproof element is/are machined from sheet metal.

According to some embodiments of the present application, the battery pack further includes a sealing member between the bottom case and the upper case and abutting against the bottom case and the upper case.

According to some embodiments of the application, the battery pack further comprises a bolt and a nut, the bottom case is provided with a first through hole, the top cover is provided with a second through hole corresponding to the position of the first through hole, and the bolt penetrates through the first through hole and the second through hole and is connected with the nut.

According to some embodiments of the present application, the battery pack further includes a cooling device disposed at a side of each of the battery modules.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The present application is further described with reference to the following figures and examples, in which:

fig. 1 is an exploded view of a battery pack according to an embodiment of the present application;

fig. 2 is a schematic cross-sectional view of a battery module according to an embodiment of the present disclosure;

FIG. 3 is an enlarged view of area A in FIG. 2;

fig. 4 is a schematic view of another embodiment of the top cover of the battery pack of the present invention.

Reference numerals:

the box body 100, the bottom shell 110, the accommodating groove 111, the top cover 120, the upper shell 121, the fireproof piece 122, the first supporting column 1221 and the heat insulation cavity 130;

the battery module 200, the battery core 210 and the explosion-proof valve 211;

cooling device 300, receiving chamber 400.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

In the description of the present application, it should be understood that the positional descriptions referred to, for example, the directions or positional relationships indicated by upper, lower, front, rear, left, right, etc., are based on the directions or positional relationships shown in the drawings, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and thus, should not be construed as limiting the present application.

In the description of the present application, the meaning of a plurality is one or more, the meaning of a plurality is two or more, and the above, below, exceeding, etc. are understood as excluding the present number, and the above, below, within, etc. are understood as including the present number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present application, unless otherwise expressly limited, terms such as set, mounted, connected and the like should be construed broadly, and those skilled in the art can reasonably determine the specific meaning of the terms in the present application by combining the detailed contents of the technical solutions.

In the description of the present application, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Fig. 1 is an exploded schematic view of a battery pack according to an embodiment of the present application, and fig. 2 is a schematic cross-sectional view of the battery pack according to the embodiment of the present application, which is combined with fig. 1 and fig. 2, the battery pack according to the present embodiment includes: a case 100, and a plurality of battery modules 200.

The box 100 includes a top cover 120 and a bottom cover 110, the bottom cover 110 has a receiving groove 111, one side of the receiving groove 111 has an opening, the top cover 120 is connected to the bottom cover 110 at the opening and seals the opening, the receiving groove 111 and the top cover 120 define a receiving cavity 400, the top cover 120 includes an upper shell 121 and a fireproof member 122, the fireproof member 122 is connected to one side of the upper shell 121 facing the receiving groove 111, and a heat insulation cavity 130 is formed between the fireproof member 122 and the upper shell 121. The battery module 200 is disposed in the accommodating cavity 400, the battery module 200 includes a battery cell 210, the battery cell 210 has an explosion-proof valve 211, and the explosion-proof valve 211 faces the heat insulation cavity 130.

Specifically, the top cover 120 includes an upper shell 121 and a fireproof member 122, and an insulating cavity 130 is formed between the fireproof member 122 and the upper shell 121. Each battery module 200 is disposed in the accommodating chamber 400, and the explosion-proof valve 211 on the battery cell 210 in the battery module 200 faces the fireproof member 122. When the battery cell 210 is out of control due to heat, the high-temperature and high-pressure gas can open the explosion-proof valve 211 at the explosion-proof opening, and the high-temperature and high-pressure gas or flame can be ejected from the explosion-proof opening at a high speed to burn the fireproof piece 122. The heat insulation cavity 130 is formed between the fireproof element 122 and the upper casing 121, so that the time for transferring heat to the upper casing 121 can be reduced. In addition, the heat insulation chamber 130 can also obstruct the deformation of the fireproof member 122 caused by high temperature from being transmitted to the upper casing 121, so as to reduce the deformation degree of the upper casing 121, thereby preventing the upper casing 121 from being burnt through and preventing the fire from spreading.

It should be noted that, the size of the thermal insulation cavity 130 between the fire-proof member 122 and the upper casing 121 is related to the thermal runaway degree of the battery cell 210, and when the thermal runaway degree of the battery cell 210 is predicted to be larger, the size of the thermal insulation cavity 130 can be adaptively increased, so that the fire-proof member 122 can resist flame burning.

Because the upper casing 121 and the fireproof piece 122 are designed in a layered manner, the fireproof piece 122 and the upper casing 121 can be made of different materials, the fireproof piece 122 is made of a high-temperature-resistant material, and the upper casing 121 is made of a high-strength material, so that the top cover 120 has high strength and high-temperature resistance, the material performance requirement is reduced, and the cost is saved. Furthermore, it can be appreciated that the degree of thermal runaway is not the same for different cells 210. The fire barrier 122 also has a different ability to withstand the flame impact that it is required to resist in order to prevent the upper casing 121 from burning through. Since the top cover 120 in this embodiment is designed in a layered manner, the fireproof members 122 need to be replaced accordingly. For example, for the battery cell 210 with a higher thermal runaway degree, the thicker or more high-temperature-resistant fireproof piece 122 can be replaced, and the whole top cover 120 does not need to be redesigned, so that the design cost is saved.

In some embodiments, a support structure is further disposed between the fire-proof member 122 and the upper case 121 for supporting the fire-proof member 122 and the upper case 121.

Specifically, the supporting structure may be a first supporting column 1221 disposed on a surface of the fireproof element 122 facing the upper case, the first supporting column 1221 and the fireproof element 122 may be integrally processed, and one end of the first supporting column 1221 close to the upper case 121 abuts against the upper case 121. The supporting structure may also be a second supporting pillar (not shown in the figure) disposed on a surface of the upper casing 121 facing the fire-proof member 122, the second supporting pillar and the upper casing 121 are integrally processed, and an end of the second supporting pillar close to the fire-proof member 122 abuts against the fire-proof member 122. That is, the support structure is located between the upper wall and the lower wall of the insulating chamber 130 to prevent the insulating chamber 130 from collapsing, so as to ensure the insulating effect of the insulating chamber 130. In addition, it should be noted that the first support column 1221 and the second support column avoid the area above the cell 210 directly opposite to the explosion-proof valve 211, so as to ensure that the area above the cell 210 directly opposite to the explosion-proof valve 211 is provided with the thermal insulation cavity 130.

In some embodiments, the upper shell 121 and the flame proof member 122 are connected by resistance welding. Specifically, the upper case 121 is connected to the first support column 1221 by resistance welding, and when resistance welding is performed, metal filling is not required, so that the productivity is high, and the requirement for mass production can be met. In addition, since the deformation of the welded member by resistance welding is small, when the upper case 121 and the fireproof member 122 are welded, the deformation of the upper case 121 and the fireproof member 122 is small, and the surface flatness of the upper case 121 is improved, thereby improving the dimensional accuracy of the entire battery pack.

The welding point of fire prevention piece 122 and epitheca 121 can set up on first support column 1221, so that each first support column 1221 welds in epitheca 121, improve the joint strength of fire prevention piece 122 and epitheca 121, can make first support column 1221 have taut effect to the chamber wall in thermal-insulated chamber 130 simultaneously, prevent that epitheca 121 orientation from deviating from the direction deformation in thermal-insulated chamber 130 and producing the swell, ensure the plane degree of epitheca 121, thereby improve the installation accuracy when the battery package uses.

In some embodiments, a surface of the fire-proof member 122 facing away from the upper case 121 is provided with a plurality of fire-proof portions (not shown), the fire-proof portions protrude from a surface of the fire-proof member 122 facing away from the upper case 121, and each fire-proof portion is aligned with the explosion-proof valve 211 of each cell 210. Specifically, the fire prevention piece 122 plays the main position that is just to the explosion-proof valve 211 of electric core 210 of fire prevention effect, therefore, this implementation is with the thickness increase of the position department that the fire prevention piece 122 is just to explosion-proof valve 211, the surface that deviates from epitheca 121 of fire prevention piece 122 sets up a plurality of fire prevention portions promptly, so that the position that fire prevention piece 122 and explosion-proof valve 211 correspond satisfies the fire prevention requirement, and need not to set up monoblock fire prevention piece 122 to uniform thickness, promptly with except the position that corresponds with explosion-proof valve 211, other regions of fire prevention piece 122 can set up to thinner thickness, in order to alleviate the quality of fire prevention piece 122, and the manufacturing cost is reduced simultaneously.

In addition, it can be understood that, the thermal runaway degrees of the battery cells 210 are different, and the fireproof members 122 with different thicknesses can be set according to different thermal runaway degrees, for example, the fireproof performance of the fireproof members 122 is improved.

It should be noted that the fire-proof portion is disposed on the surface of the fire-proof member 122 away from the upper casing 121, because if the fire-proof portion is disposed on the surface of the fire-proof member 122 close to the upper casing 121, the gap of the thermal insulation chamber 130 is reduced, thereby affecting the thermal insulation effect.

Referring to fig. 4, fig. 4 is a schematic view illustrating another embodiment of the top cover of the battery pack according to the present invention, in some embodiments, a plurality of fire-proof members 122 are connected to a surface of the upper case 121 facing the bottom case 110, and each fire-proof member 122 has a space therebetween and is aligned with the explosion-proof valve 211 of each cell 210.

Specifically, the plurality of fire-proof members 122 are connected to the surface of the upper case 121 facing the accommodating groove, and each fire-proof member 122 is aligned with the explosion-proof valve 211 of each cell 210 one by one, and a space is provided between each fire-proof member 122. That is, the top cover 120 is only provided with the fire prevention piece 122 at the corresponding position of the explosion-proof valve 211, and each fire prevention piece 122 can support the heat generated by each battery cell 210 in a one-to-one correspondence manner, and the position of the upper shell 121 corresponding to each battery cell 210 is effectively prevented from being burnt through, so that the whole top cover 120 does not need to be set to be a double-layer structure, and the weight and the manufacturing cost of the battery module 200 can be reduced while the heat is effectively insulated.

In the above embodiment, the fire prevention member 122 is detachably coupled to the upper case 121. Specifically, the fire-proof member 122 is directly opposite to the explosion-proof valve 211 of the battery cell, and when the battery cell 210 is out of thermal control, the explosion-proof valve 211 bursts flames to directly irradiate the fire-proof member 122, so that the fire-proof member 122 is damaged by burning. The fire prevention piece 122 of this embodiment is connected through detachably connected modes such as joint or cementing, when the maintenance, only need with the fire prevention piece 122 replacement of damage can, need not to change monoblock top cap 120, practice thrift the cost.

In some embodiments, a first connecting portion (not shown) is disposed on a side of the bottom housing 110 facing the upper housing 121, a second connecting portion (not shown) is disposed on a side of the upper housing 121 facing the bottom housing 110, the first connecting portion and the second connecting portion are detachably connected, and a first positioning structure (not shown) is disposed between the first connecting portion and the second connecting portion and used for defining a relative position between the upper housing 121 and the bottom housing 110.

Specifically, the first positioning structure may be a positioning pillar disposed on the bottom case 110 and a positioning hole disposed on the upper case 121, and the positioning pillar may be disposed in the positioning hole. The positioning column can be any column body such as a cylinder, a triangular prism, a quadrangular prism and the like, and the positioning hole corresponds to the positioning column and is a round hole, a triangular hole, a quadrangular hole and the like. In the using process, the positioning column is clamped in the positioning hole to position the bottom shell 110 and the top cover 120. The first support column 1221 is prevented from being located above the explosion-proof valve 211, or when the upper case 121 is connected to a plurality of fire-proof members 122, alignment of each fire-proof member 122 with the explosion-proof valve 211 can be ensured by positioning in the positioning column and the positioning hole.

In addition, the locating hole runs through upper casing 121, consequently when stretching into the locating hole with the reference column, can see the reference column through the locating hole, makes things convenient for the reference column to aim at the locating hole.

The first positioning structure may further include a groove disposed on the first connecting portion and a protrusion disposed on the second connecting portion, and the protrusion can be engaged with the groove to define a relative position between the upper case 121 and the bottom case 110.

In addition to the above embodiments, a second positioning structure (not shown) is further provided between the fire-proof member 122 and the upper casing 121, and the second positioning structure is used for defining the relative position of the fire-proof member 122 and the upper casing 121. Specifically, the second positioning structure includes a first positioning groove disposed on the upper case 121 and a first positioning block disposed on the fireproof member 122. First locating slot sets up in the surface of epitheca 121 towards fire prevention piece 122, and first locating piece sets up in the surface of fire prevention piece 122 towards the epitheca, and first locating piece supports the side of holding in first locating slot to inject the relative position of fire prevention piece 122 and epitheca 121, improve the installation accuracy of fire prevention piece 122, thereby improve the position accuracy of fire prevention piece 122 and electric core 210 explosion-proof valve 211.

It should be noted that the second positioning structure can also be a second positioning slot disposed on the fireproof member 122 and a second positioning column disposed on the upper casing 121, as long as the relative position of the fireproof member 122 and the upper casing 121 can be defined.

In some embodiments, either or both of the upper case 121 and the fireproof member 122 are machined from sheet metal. Specifically, the sheet metal part formed by sheet metal processing has the advantages of high melting point and high strength. Therefore, the high temperature resistance of the fireproof piece 122 and the upper shell 121 can be enhanced through sheet metal processing, and the damage speed of the fireproof piece 122 and the upper shell 121 caused by high temperature can be reduced.

In some embodiments, the battery pack further includes a sealing member (not shown) located between the bottom case 110 and the upper case 121 and tightly coupled to the bottom case 110 and the upper case 121.

Specifically, in order to prevent the flame from being ejected from the gap between the bottom case 110 and the upper case 121, the present embodiment provides a sealing member between the bottom case 110 and the upper case 121, the sealing member being made of a high temperature resistant material, such as a graphite gasket. The sealing member is in close contact with the bottom case 110 and the upper case 121, preventing a gap from being generated between the bottom case 110 and the upper case 121.

In some embodiments, the battery pack further includes a bolt (not shown) and a nut (not shown), the bottom case 110 has a first through hole (not shown), the top cover 120 has a second through hole (not shown), the sealing member is located between the first connecting portion and the second connecting portion, and the bolt is inserted through the first through hole and the second through hole and connected to the nut.

Specifically, the bottom shell 110 and the top cover 120 are locked together by bolts and nuts, the nuts are rotated in the assembling process to clamp the bottom shell 110 and the top cover 120, the bolts can be under the action of a pre-tightening force in the connection process of the bolts and the nuts, and when the battery cell 210 is out of control due to heat, the temperature in the accommodating cavity 400 rises to increase the pressure. At this time, the acting force between the bottom shell 110 and the upper shell 121 is a pushing force generated by the pressure inside the accommodating cavity 400 and a pulling force generated by the pretightening force of the bolt, and the pulling force generated by the pretightening force to the bottom shell 110 and the upper shell 121 can resist the pushing force generated by the pressure inside the accommodating cavity 400, so that the top cover 120 is prevented from being lifted, and the fire spreading is avoided.

In addition, the preload of the bolts always presses the sealing members, so that the sealing members are in close contact with the bottom case 110 and the top cover 120. A gap is prevented from occurring between the sealing member and the top cover 120 and the bottom case 110, and flames are prevented from being ejected from the gap, thereby preventing the spread of fire.

In addition, a plurality of bolts are arranged along the outlines of the bottom shell 110 and the top cover 120, and the sizes of the bolts can be selected according to actual requirements, so that the connection strength between the bottom shell 110 and the upper shell 121 is improved, and the top cover 120 and the bottom shell 110 are prevented from being lifted when the battery cell 210 is out of thermal control.

Referring to fig. 1, in some embodiments, the battery pack further includes a cooling device 300, and the cooling device 300 is disposed at a side of each battery module 200. Specifically, the cooling device 300 may be a liquid cooling plate, and in a high-temperature environment, such as summer, the cooling device 300 may cool the battery cell 210, so as to prevent an accident caused by an excessively high temperature. The cooling device 300 may be disposed around the side and end surfaces of the battery module 200, thereby enhancing the cooling effect.

The embodiments of the present application have been described in detail with reference to the drawings, but the present application is not limited to the embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present application. Furthermore, the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

Claims

1. A battery pack, comprising:

the box body comprises a top cover and a bottom shell, the bottom shell is provided with a containing groove, one side of the containing groove is provided with an opening, the top cover is connected to the bottom shell at the opening and covers the opening, the containing groove and the top cover define a containing cavity, the top cover comprises an upper shell and a fireproof piece, the fireproof piece is located on one side of the upper shell, which faces the containing cavity, and a heat insulation cavity is formed between the fireproof piece and the upper shell;

the battery modules are arranged in the containing cavity and comprise a plurality of battery cells, each battery cell is provided with an explosion-proof valve, and the explosion-proof valves face the heat insulation cavity.

2. The battery pack of claim 1, wherein a support structure is further disposed between the fireproof member and the upper case for supporting the fireproof member and the upper case.

3. The battery pack according to claim 1, wherein the upper case and the fireproof member are connected by resistance welding.

4. The battery pack of claim 1, wherein a surface of the fireproof member facing away from the upper case is provided with a plurality of fireproof portions, the fireproof portions protrude from the surface of the fireproof member facing away from the upper case, and each fireproof portion is aligned with the explosion-proof valve of each battery cell.

5. The battery pack of claim 1, wherein a plurality of the fire-proof members are connected to a surface of the upper case facing the receiving cavity, and the fire-proof members are spaced apart from each other and aligned with the explosion-proof valves of the battery cells.

6. The battery pack of claim 5, wherein the fire prevention member is detachably coupled to the upper case.

7. The battery pack according to claim 2 or 5, wherein a first connecting portion is provided on a side of the bottom case facing the upper case, a second connecting portion is provided on a side of the upper case facing the bottom case, the first connecting portion and the second connecting portion are detachably connected, and a first positioning structure is provided between the first connecting portion and the second connecting portion and used for defining a relative position of the upper case and the bottom case.

8. The battery pack of claim 7, wherein a second locating feature is provided between the fire stop and the upper housing, the second locating feature defining a relative position of the fire stop and the upper housing.

9. The battery pack of claim 1, wherein the upper case and/or the fireproof member is formed by sheet metal machining.

10. The battery pack according to claim 1, further comprising a cooling device provided at a side of each of the battery modules.