CN219393529U - Shell, battery and battery module - Google Patents

Abstract

The application provides a casing, battery and battery module relates to motor technical field. The housing includes a shell portion and an accommodating portion defined by the shell portion, the accommodating portion being for accommodating a pole group of the battery; the shell part comprises a plurality of side parts, the shell part further comprises a concave part which is arranged on one of the side parts with the largest area, the concave part is arranged on the middle part of the one with the largest area in the height direction of the shell or the position of the shell corresponding to the middle part of the pole group in the height direction of the shell, and the concave part is arranged on the inner side of the shell. According to the casing that this application provided, the casing provides the intermediate expansion space for the inflation of utmost point group for after the inflation of utmost point group, the part of utmost point group holds in the intermediate expansion space, and slows down the casing and take place expansion deformation, can also reserve electrolyte passageway in the regional middle of extremely group, makes the battery in the circulation later stage, can in time supply electrolyte.

Description

Shell, battery and battery module

Technical Field

The application relates to the technical field of batteries, in particular to a shell, a battery and a battery module.

Background

In order to meet the requirements of high energy density and long service life of electric automobiles, lithium ion batteries using nickel-cobalt-manganese ternary materials as positive electrodes have become important points of industrial research. Designing a safe, reliable and durable battery system is an important condition for ensuring healthy development of new energy electric automobile industry.

In the charge and discharge process of the battery, due to continuous release and intercalation of lithium ions, the volume of the battery can be expanded in a certain proportion, so that the battery generates certain expansion force. The swelling force not only deteriorates the safety of the battery system but also deteriorates the life of the battery. In addition, the magnitude of the swelling force increases as the number of battery cycles increases. And, the expansion force increase of battery can aggravate the extrusion between positive, negative pole piece and the diaphragm, leads to the electrolyte of utmost point group middle part to be extruded in the circulation process, and this can lead to in the circulation later stage casing free electrolyte can't in time to the middle of the utmost point group, leads to ion channel to miss, and the lithium precipitation appears in negative pole middle part, produces the potential safety hazard.

Disclosure of Invention

In view of the above, the present application provides a housing, a battery and a battery module, and aims to solve the above technical problems.

In a first aspect, the present application provides a housing comprising a shell portion and a receiving portion defined by the shell portion for receiving a pole group of a battery;

wherein the shell portion includes a plurality of side portions, the shell portion further includes a recess provided to one of the plurality of side portions having a largest area, the recess is provided to a middle portion of the one having the largest area in a height direction of the shell or a position of the shell corresponding to a position of the middle portion of the pole group in the height direction of the shell, and the recess is provided to an inner side of the shell.

Preferably, the dimension of the recess in the longitudinal direction of the housing is the same as the dimension of the accommodation portion in the longitudinal direction.

Preferably, the depth of the recess recessed into the largest one of the areas is 25% to 60% of the thickness of the largest one of the areas.

Preferably, the depth to which the concave portion is recessed into the one of the areas where the area is largest is 0.2 to 0.3mm; and/or the thickness of the largest one of the areas is 0.5 to 0.8mm.

Preferably, the dimension of the recess in the height direction of the housing is 5 to 10mm.

Preferably, the housing is rectangular parallelepiped in shape, and includes two largest ones of the areas facing each other, each largest one of the areas being provided with the recess.

Preferably, the housing further includes a cover plate connected with the shell portion, the cover plate being disposed at a top or side portion of the shell portion, the cover plate closing the accommodating portion.

In a second aspect, the present application provides a battery comprising a housing as described above.

Preferably, the battery further comprises a pole group, which is a lamination structure or a winding structure.

In a third aspect, the present application provides a battery module comprising a plurality of batteries as described above.

According to the casing that this application provided, the inboard at the biggest one of area that is big face sets up the concave part, the concave part is at the middle part of the direction of height of casing, wherein, the biggest one of area (big face) is at the ascending lateral part of polar group expansion direction, utilize the middle concave part that sets up in the inboard, the casing in this application embodiment provides the intermediate expansion space for the expansion of polar group for the part of polar group after the expansion is in the intermediate expansion space, and slow down the casing and take place expansion deformation, can also reserve electrolyte passageway in polar group intermediate region, make the battery in the circulation later stage, can in time replenish electrolyte.

In order to make the above objects, features and advantages of the present application more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered limiting the scope, and that other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 shows a schematic diagram of an isometric view of a battery provided in accordance with an embodiment of the present application;

fig. 2 shows a schematic diagram of a cross-sectional view of a battery provided according to an embodiment of the present application.

Reference numerals:

10-a housing; 11-a shell portion; 12-a housing; 13-the largest one; 14-a recess; 15-cover plate; 16-pole; 17-explosion-proof valve; 18-pole groups; f1-the height direction; f2-length direction.

Detailed Description

The following description of the embodiments of the present application will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the utility model are shown. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of description of the present application and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art in a specific context.

In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be regarded as not exist and not within the protection scope of the present application.

According to a first aspect of the present application, a housing 10 is provided, and the structure and operation of the housing 10 will be described in detail below with reference to fig. 1 and 2.

Prior to the present application, the case 10 of the battery in the prior art generally expands during the cyclic charge and discharge, and according to the existing battery structure, the expansion generally occurs on a large surface of the case 10 (here, the arrow direction in fig. 1 may be combined with fig. 1, the thickness direction of the case 10, the expansion direction of the battery), that is, the largest area 13 mentioned in the following description. In the prior art, such expansion is often not effectively handled, and in general, the prior art may use a method of reinforcing a large surface, for example, may increase the thickness of the large surface to avoid reducing such expansion, but this inevitably occupies the accommodation space inside the case 10, resulting in a reduction in the installation space of the pole group 18 of the battery, and thus in a reduction in the energy density of the battery.

In other prior teachings, since the battery case 10 is generally made of a metal material, in other words, the battery case 10 is generally of a metal structure, adjacent side portions are generally connected by welding, and the connection strength of the battery case 10 is often high at the peak position of the battery case 10, the prior teachings may weaken the connection strength near the peak position of the battery case 10, such as the connection strength of the top and bottom of the battery case 10, in order to expect the binding force of the top and bottom of the battery case 10 to the expanded middle portion to avoid damage to the top and bottom of the battery case 10, and to maintain the battery case 10 in a relatively uniform form in appearance. However, this prior teaching does not essentially solve the problem of the expansion of the middle of the case 10 of the battery, but merely weakens the adverse effect of the expansion of the middle of the case 10 of the battery.

In the present embodiment, the case 10 may include a case portion 11 and a receiving portion 12 defined by the case portion 11, the receiving portion 12 for receiving a pole group 18 of the battery. Wherein the shell portion 11 includes a plurality of side portions, the shell portion 10 further includes a recess 14 provided at one 13 of the plurality of side portions having the largest area, the recess 14 is provided at a position of the shell portion 10 corresponding to a position of a middle portion of the one 13 having the largest area in a height direction F1 of the shell portion 10 or a middle portion of the pole group 18 in the height direction F1 of the shell portion 10, and the recess 14 is provided at an inner side of the shell portion 10.

Thus, according to the case 10 provided in the embodiment of the present application, the recess 14 is provided at the inner side of the one 13 with the largest area, that is, the large surface, and the recess 14 is provided at the middle part in the height direction F1 of the case 10 or at the position of the case 10 corresponding to the middle part of the pole group 18 in the height direction F1 of the case 10, wherein the one 13 (large surface) with the largest area can be used as the side part in the expansion direction of the pole group 18, and the recess 14 provided at the inner side of the case 11 is utilized, the case 10 in the embodiment of the present application provides the middle expansion space for the expansion of the pole group 18, so that after the expansion of the pole group 18, the part of the pole group 18 is accommodated in the middle expansion space, and the expansion deformation of the case 10 is slowed down, and the electrolyte channel can be reserved in the middle region of the pole group 18, so that the electrolyte can be timely replenished in the later stage of the cycle.

In the embodiment, it is to be noted that the "height direction F1" of the housing 10 mentioned in the above description is determined in the following manner: the housing 10 includes a cover plate 15 for closing the accommodating portion 12, and a direction defined by the cover plate 15 and a side portion of the housing portion 11 facing the cover plate 15 together is a height direction F1. Further, the height direction F1 and the length direction F2 described below have been shown in fig. 2.

In the following description, the concave portion 14 is provided inside one 13 having the largest area.

In the embodiment, the dimension of the recess 14 in the longitudinal direction F2 of the housing 10 is the same as the dimension of the accommodating portion 12 in the longitudinal direction F2 of the housing 10. Due to this arrangement, according to the case 10 provided in the embodiment of the present application, the recess 14 has the span in the longitudinal direction F2 of the case 10 of the accommodating portion 12, so that the recess 14 is formed as a substantial groove, and the recess 14 can ensure that the space is provided for the expansion of the pole group 18 for each position of the pole group 18 corresponding in sequence in the longitudinal direction F2 of the case 10, thereby further slowing down the occurrence of deformation of the case 10 under the action of the expansion force of the pole group 18. In the embodiment, preferably, as shown in fig. 1 and 2, the recess 14 may extend along the length direction F2 of the housing 10, and the processing of the recess 14 can be relatively simplified because the reference of the processing can be made with the length direction F2 of the housing 10. Further, in the embodiment, the length direction F2 of the housing 10 and the height direction F1 of the housing 10 may be perpendicular to each other.

In an embodiment, the recess 14 is recessed by 25% to 60% of the thickness of the largest depth footprint 13 of the largest area 13. According to the housing 10 provided in the embodiment of the present application, the depth of the recess 14 occupies 25% to 60% of the thickness of the one 13 having the largest area, which combines the accommodability of the expansion of the pole group 18 and the overall strength of the housing 10. In the embodiment, on the one hand, if the thickness of the one 13 with the largest depth occupation area of the recess 14 is smaller than 25%, the thickness of the one 13 with the largest area inevitably needs to be increased in order to be able to effectively accommodate the expansion of the pole group 18; on the other hand, if the thickness of the one 13 having the largest depth and area of the recess 14 is larger than 60%, the strength of the one 13 having the largest area and the housing 10 are affected, which is disadvantageous in terms of stability of the structure of the housing 10.

In the embodiment, specifically, the depth of one 13 of the recesses 14 having the largest recessed area is 0.2 to 0.3mm; and/or the thickness of the one 13 with the largest area is 0.5 to 0.8mm. For example, the depth of the recess 14 into the largest one 13 is 0.2 to 0.3mm, or the thickness of the largest one 13 is 0.5 to 0.8mm. As another example, the depth of the recess 14 into the largest one 13 is 0.2 to 0.3mm, and the thickness of the largest one 13 is 0.5 to 0.8mm, which will be described as an example. That is, the depth of the recess 14 may be 0.2 to 0.3mm, and the thickness of the large face may be 0.5 to 0.8mm. In an embodiment, the depth of the recess 14 may be 0.2mm, 0.25mm, and 0.3mm, and the thickness of the large face may be 0.5mm, 0.6mm, 0.7mm, and 0.8mm, as examples. The recess 14 and the large face may have a variety of combinations, for example, the recess 14 may have a depth of 0.2mm and the corresponding large face may have a thickness of 0.5mm, 0.6mm, 0.7mm, and 0.8, mm; the depth of the recess 14 may be 0.25mm and the corresponding large face thickness may be 0.5mm, 0.6mm, 0.7mm and 0.8, mm; the depth of the recess 14 may be 0.3mm and the corresponding large face thickness may be 0.5mm, 0.6mm, 0.7mm and 0.8, mm.

In the embodiment, the dimension of the recess 14 in the height direction F1 of the housing 10 is 5 to 10mm. With this arrangement, the recess 14 has a sufficient size in the height direction F1 of the case 10 to provide a sufficient space for the pole group 18 to expand, thereby slowing down the deformation of the case 10, while this size arrangement of the recess 14 takes into account the strength of the case 10 and the one 13 having the largest area. In particular, on the one hand, if the dimension of the recess 14 in the height direction F1 of the housing 10 is less than 5mm, it is disadvantageous that the recess 14 provides an effective expansion space for the pole group 18, which still leads to deformation of the housing 10; on the other hand, if the dimension of the recess 14 in the height direction F1 of the housing 10 is greater than 10mm, the width of the recess 14 is too wide, which may result in a decrease in the strength of the one 13 having the largest area, and further, in a decrease in the strength of the housing 10, which is disadvantageous in ensuring the structural stability of the housing 10.

In an embodiment, as shown in fig. 1 and 2, the case 10 may be in a rectangular parallelepiped shape, and the case 10 may include one 13 having the largest of two areas opposing each other, that is, the case 10 includes two large faces opposing each other in the thickness direction of the case 10. In an embodiment, one 13 of the largest areas may be provided with recesses 14. This facilitates sharing of the expansion space provided for the pole group 18 over two large faces, thereby reducing the depth of the recess 14 provided by a single large face and thus facilitating ensuring the strength of each large face.

Furthermore, in embodiments, the recess 14 may have a different arrangement of the inner side surfaces. Referring now to fig. 2, in fig. 2, the thickness of the two large faces is shown in exaggerated dimensions in fig. 2 to better illustrate the recess 14, while the thickness of the cover plate 15 and the thickness of the side opposite the cover plate 15 are shown in reduced dimensions in fig. 2 to avoid affecting the display of the large faces. In fig. 2, as mentioned in the above description, the recess 14 may be a substantial groove, and the inner side portion thereof may be sequentially vertically three planes, so that the cross section of the recess 14 is rectangular as shown in fig. 2. In some examples, not shown, the inner side of the recess 14 may be half of an inner cylindrical surface, in which case the cross-section of the recess 14 is semi-circular, or the inner side of the recess 14 may be a portion of an inner cylindrical surface, in which case the cross-section of the recess 14 may be a minor arc. Furthermore, in some examples, not shown, the recess 14 may be V-shaped in cross-section, i.e. the inner side of the recess 14 may comprise two planes that are angled with respect to each other.

In practice, the housing 10 may further comprise a cover plate 15, the cover plate 15 being connectable to the shell portion 11, the cover plate 15 closing the receiving portion 12. In an embodiment, the cover plate 15 is located at the top or side of the housing 10, for example, at the top, the cover plate 15 may be provided with an explosion-proof valve 17, and the cover plate 15 may also be provided with a through hole through which the pole 16 passes, as shown in both fig. 1 and 2. Further, in an embodiment, the housing 10 may be an aluminum structure.

According to the embodiment of the application, based on the background of reducing the battery cyclic expansion force and improving the lithium precipitation in the middle area of the battery negative electrode sheet, the middle of the shell 10 is thinned, the thickness of the middle area of the shell 10 is reduced, an expansion space can be reserved for the battery core sheet, and meanwhile, an electrolyte channel can be reserved for the middle area of the electrode group 18, so that the battery can timely supplement electrolyte in the later cycle period. The method is simple to operate, does not increase the complexity of the battery system, and is easy to realize industrialization.

According to a second aspect of the embodiments of the present application, a battery is provided, which includes the above housing 10 and also includes the above advantages, and is not described herein. The battery also comprises an electric core, wherein the electric core can be of a lamination structure or a winding structure, and the electric core can comprise a positive electrode sheet, a negative electrode sheet and a diaphragm. In the embodiment, particularly for the laminated battery, the degree of freedom of the edge portions of the positive and negative electrode sheets is large, and a certain degree of force can be released in the length or width direction, but the middle portion of the electrode sheet can only release force in the thickness direction due to the mutual extrusion between the upper, lower, left and right particles. Therefore, when the gap in the aluminum shell is fixed, the more pole pieces in the battery are assembled, the higher the assembly ratio is, the larger the expansion force in the thickness direction is, the transmission of lithium ions is limited, the internal impedance of the battery is increased, the capacity attenuation of the battery is accelerated, and the deformation of the shell 10 can be well slowed down by the shell 10 in the embodiment of the application.

According to a third aspect of the embodiments of the present application, a battery module is provided, which includes a plurality of batteries as described above, and also includes the above beneficial effects, which are not described herein again.

The foregoing description is only of the preferred embodiments of the present application, and is not intended to limit the scope of the present application, but rather, the present application is intended to cover any variations of the equivalent structures described herein or shown in the drawings, or the direct/indirect application of the present application to other related technical fields.

Claims (10)

1. A housing (10), characterized in that the housing (10) comprises a shell portion (11) and a receiving portion (12) defined by the shell portion (11), the receiving portion (12) being for receiving a pole group (18) of a battery;

wherein the shell portion (11) includes a plurality of side portions, the housing (10) further includes a recess (14) provided in one (13) of the plurality of side portions having the largest area, the recess (14) is provided in a middle portion of the one (13) having the largest area in a height direction (F1) of the housing (10) or in a position of the housing (10) corresponding to a middle position of the pole group (18) in a height direction (F1) of the housing (10), and the recess (14) is provided in an inner side of the housing (10).

2. The housing (10) according to claim 1, wherein a dimension of the recess (14) in a length direction (F2) of the housing (10) is the same as a dimension of the accommodation portion (12) in the length direction (F2).

3. The housing (10) according to claim 1, wherein the depth of the recess (14) recessed into the largest one of the areas (13) is 25 to 60% of the thickness of the largest one of the areas (13).

4. A housing (10) according to claim 3, wherein the depth to which the recess (14) is recessed into the largest one of the areas (13) is 0.2 to 0.3mm; and/or the thickness of the largest one of the areas (13) is 0.5 to 0.8mm.

5. The housing (10) according to claim 1, characterized in that the recess (14) has a dimension in the height direction (F1) of the housing (10) of 5 to 10mm.

6. The housing (10) according to claim 1, wherein the housing (10) is rectangular parallelepiped in shape, the housing (10) comprising two largest-area ones (13) facing each other, each largest-area one (13) being provided with the recess (14).

7. The housing (10) according to any one of claims 1 to 6, wherein the housing (10) further comprises a cover plate (15), the cover plate (15) being connected with the shell portion (11), the cover plate (15) being provided at a top or side portion of the shell portion (11), the cover plate (15) closing the accommodating portion (12).

8. A battery, characterized in that it comprises a casing (10) according to any one of claims 1 to 7.

9. The battery according to claim 8, further comprising a pole group (18), the pole group (18) being of laminated or wound construction.

10. A battery module comprising a plurality of batteries according to claim 8 or 9.