CN220042091U - Battery box and battery pack - Google Patents

Abstract

The utility model relates to the technical field of batteries, in particular to a battery box and a battery pack, wherein the battery box comprises a frame, the frame comprises an inner side part, a middle part and an outer side part which are arranged along a first direction, the inner side part and the outer side part are respectively positioned at the inner side and the outer side of the middle part, the inner side part, the middle part and the outer side part are respectively provided with a cavity, the middle part is provided with two middle side walls which are arranged at intervals along the first direction, the inner side part is provided with an inner side wall, the inner side wall is positioned at the inner side of the middle side wall of the inner side at intervals, the outer side part is provided with an outer side wall, and the outer side walls are positioned at the outer side of the middle side wall of the outer side at intervals; wherein the thickness of the middle side wall is smaller than the thickness of the inner side wall and smaller than the thickness of the outer side wall. Through the structural design, when the frame is impacted externally, the two middle side walls with smaller thickness of the middle part deform and collapse before the inner side wall and the outer side wall with larger thickness, so that the middle part provides the function of buffering and absorbing energy.

Description

Battery box and battery pack

Technical Field

The utility model relates to the technical field of batteries, in particular to a battery box and a battery pack.

Background

In the design scheme of the existing battery pack, the frame of the battery box encloses a box inner cavity for accommodating the battery, when the frame is impacted externally, the frame can directly transmit impact force to the battery, so that the battery is damaged, and the safety and the service life of the battery pack are affected.

Disclosure of Invention

The utility model aims to overcome at least one defect of the prior art and provide a battery box body with a frame having a buffering and energy absorbing function.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

according to an aspect of the present utility model, there is provided a battery case, wherein the battery case includes a frame including an inner side portion, a middle portion, and an outer side portion arranged in a first direction, the inner side portion and the outer side portion being located inside and outside the middle portion, respectively, the inner side portion, the middle portion, and the outer side portion having cavities, respectively, the inner side portion being flush with a bottom of the middle portion, and a ratio of a height of the inner side portion to a height of the middle portion being 0.5 to 1, the middle portion having two middle side walls arranged at intervals in the first direction, the inner side portion having an inner side wall located inside the middle side wall at intervals, the outer side portion having an outer side wall located outside the middle side wall at intervals; wherein the thickness of the intermediate side wall is smaller than the thickness of the inner side wall and smaller than the thickness of the outer side wall.

According to the technical scheme, the battery box body provided by the utility model has the advantages and positive effects that:

the battery box body comprises a frame, wherein the frame comprises an inner side part, a middle part and an outer side part, the inner side part is flush with the bottom of the middle part, the ratio of the height of the inner side part to the height of the middle part is 0.5-1, the middle part is provided with two middle side walls, the inner side part is provided with inner side walls which are positioned at intervals on the inner sides of the middle side walls on the inner sides, the outer side part is provided with outer side walls which are positioned at intervals on the outer sides of the middle side walls on the outer sides, and the thickness of the middle side walls is smaller than that of the inner side walls and smaller than that of the outer side walls. Through the structural design, when the frame is impacted externally, the two middle side walls with smaller thickness of the middle part deform and collapse before the inner side wall and the outer side wall with larger thickness, so that the middle part provides the function of buffering and absorbing energy. In addition, the ratio of the height of the inner side part to the height of the middle part is 0.5-1, and when the two middle side walls of the middle part collapse, the inner side walls which do not collapse can be used for providing protection for the internal structure of the battery pack.

Another primary object of the present utility model is to overcome at least one of the above-mentioned drawbacks of the prior art, and to provide a battery pack including the above-mentioned battery case.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

according to another aspect of the utility model, a battery pack is provided, wherein the battery pack comprises the battery box body provided by the utility model.

According to the technical scheme, the battery pack provided by the utility model has the advantages and positive effects that:

the battery pack provided by the utility model has the advantages that the battery box body provided by the utility model can provide a buffering and energy absorbing function by utilizing the middle part of the frame, so that the battery damage caused by directly transmitting impact force to the battery when the battery box body is subjected to external impact is avoided, the safety of the battery pack is improved, and the service life is prolonged.

Drawings

Various objects, features and advantages of the present utility model will become more apparent from the following detailed description of the preferred embodiments of the utility model, when taken in conjunction with the accompanying drawings. The drawings are merely exemplary illustrations of the utility model and are not necessarily drawn to scale. In the drawings, like reference numerals refer to the same or similar parts throughout. Wherein:

fig. 1 is a schematic perspective view of a battery case according to an exemplary embodiment;

FIG. 2 is a schematic view, partially in section, of the battery case shown in FIG. 1;

FIG. 3 is a schematic plan sectional view of FIG. 2;

fig. 4 and 5 are schematic plan sectional views of battery cases according to two other exemplary embodiments, respectively.

The reference numerals are explained as follows:

100. a battery case;

110. a frame;

111. an inner side portion;

1111. an inner sidewall;

1112. an inner reinforcing rib;

112. an intermediate portion;

1121. a middle sidewall;

1122. a middle reinforcing rib;

113. an outer side portion;

1131. an outer sidewall;

alpha, inclination angle;

C1-C3. cavity;

D1-D9. thickness;

H. a distance;

x. first direction:

y, height direction.

Detailed Description

Exemplary embodiments that embody features and advantages of the present utility model are described in detail in the following description. It will be understood that the utility model is capable of various modifications in various embodiments, all without departing from the scope of the utility model, and that the description and drawings are intended to be illustrative in nature and not to be limiting.

In the following description of various exemplary embodiments of the utility model, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various exemplary structures, systems, and steps in which aspects of the utility model may be practiced. It is to be understood that other specific arrangements of parts, structures, example devices, systems, and steps may be utilized and structural and functional modifications may be made without departing from the scope of the present utility model. Moreover, although the terms "over," "between," "within," and the like may be used in this description to describe various exemplary features and elements of the utility model, these terms are used herein for convenience only, e.g., in terms of the orientation of the examples depicted in the drawings. Nothing in this specification should be construed as requiring a particular three-dimensional orientation of the structure in order to fall within the scope of the utility model.

Referring to fig. 1, a schematic perspective view of a battery case 100 according to the present utility model is representatively illustrated. In this exemplary embodiment, the battery case 100 according to the present utility model is described as being applied to a vehicle-mounted battery. Those skilled in the art will readily appreciate that many modifications, additions, substitutions, deletions, or other changes may be made to the specific embodiments described below in order to adapt the relevant designs of the present utility model to other types of battery devices, and such changes remain within the principles of the battery case 100 presented herein.

As shown in fig. 1, in an embodiment of the present utility model, a battery box 100 according to the present utility model includes a frame 110, where the frame 110 can enclose an inner cavity of the battery box 100, and the inner cavity may include a battery compartment, an electrical compartment, and other cavities, so as to accommodate batteries, electrical components, and the like of a battery pack. Referring to fig. 2 and 3 in combination, a partial cross-sectional schematic view of the battery case 100 is representatively illustrated in fig. 2; fig. 3 representatively shows a schematic plan sectional view of fig. 2. The structure, connection manner and functional relationship of the main components of the battery case 100 according to the present utility model will be described in detail with reference to the above drawings.

As shown in fig. 1 to 3, in an embodiment of the present utility model, the frame 110 includes an inner portion 111, an intermediate portion 112 and an outer portion 113 arranged along a first direction X, along which an inner side and an outer side of the frame 110 can be defined, and it is understood that when the battery case 100 is applied to a battery pack, a side of the frame 110 facing the battery is an inner side, and a side facing away from the battery is an outer side, and the description about the inner side and the outer side and the names of the structures with "inner side" and "outer side" in the following description can be cooperatively understood with reference to the above definition. Specifically, the inner portion 111 and the outer portion 113 are located inside and outside the intermediate portion 112, respectively. The inner portion 111 has a cavity C1, the intermediate portion 112 has a cavity C2, and the outer portion 113 has a cavity C3. The intermediate portion 112 has two intermediate side walls 1121 arranged at intervals along the first direction X, the inner side portion 111 has inner side walls 1111, the inner side walls 1111 are located at intervals inside the inner intermediate side walls 1121, the outer side portion 113 has outer side walls 1131, and the outer side walls 1131 are located at intervals outside the outer intermediate side walls 1121. On this basis, the thickness D2 of the intermediate side wall 1121 is smaller than the thickness D1 of the inner side wall 1111, and the thickness D2 of the intermediate side wall 1121 is smaller than the thickness D3 of the outer side wall 1131. Through the above structural design, when the frame 110 is impacted externally, the two middle side walls 1121 with smaller thickness of the middle portion 112 deform and collapse before the inner side wall 1111 and the outer side wall 1131 with larger thickness, so that the middle portion 112 provides the function of buffering and absorbing energy. In addition, since the ratio of the height of the inner side 111 to the height of the middle 112 is 0.5-1, the present utility model can provide protection for the internal structure of the battery pack by using the inner side wall 1111 which is not collapsed when the two middle side walls 1121 of the middle 112 collapse.

In an embodiment of the present utility model, the ratio of the height of the inner side portion 111 to the height of the middle portion 112 may be further greater than 0.7, such as 0.7, 0.8, 0.9, 1, etc. Through the above structural design, the present utility model can avoid that the height of the inner portion 111 is too small compared with that of the middle portion 112, and the inner portion 112 cannot provide enough protection function after collapsing. Furthermore, when the ratio of the height of the inner side portion 111 to the height of the middle portion 112 is less than 0.5, the inner side portion 111 with a smaller height cannot provide sufficient protection for other structures in the battery pack after the middle side wall 1121 of the middle portion 112 collapses, and only the structure in which the thickness of the middle side wall 1121 of the inner side of the middle portion 112 is designed to be equal to the thickness of the inner side wall 1111 can be adopted, which affects the buffering and energy absorbing functions of the middle portion 112. In some embodiments, the ratio of the height of the inner portion 111 to the height of the middle portion 112 may be less than 0.7, such as 0.6, 0.5, etc., but is not limited to this embodiment.

As shown in fig. 3, in an embodiment of the present utility model, the thickness D2 of the two intermediate side walls 1121 of the intermediate portion 112 may be equal. Through the structural design, the utility model can simplify the structural complexity of the frame 110 and is convenient for processing and manufacturing.

Referring to fig. 4, a plan cross-sectional view of a battery case 100 capable of embodying the principles of the present utility model is representatively illustrated in fig. 4 in another exemplary embodiment.

Unlike the embodiment shown in fig. 3, which employs a structural design in which the thicknesses D2 of the two intermediate side walls 1121 of the intermediate portion 112 are equal, as shown in fig. 4, in an embodiment of the present utility model, the thickness D4 of the outer intermediate side wall 1121 may be smaller than the thickness D5 of the inner intermediate side wall 1121. Through the above structural design, when the frame 110 receives external impact, the middle side wall 1121 of the outer side with smaller thickness deforms and collapses before the middle side wall 1121 of the inner side with larger thickness, so as to further reduce the possibility of deformation and collapse of the middle side wall 1121 of the inner side and further improve the buffer protection function of the battery.

As shown in fig. 2 and 3, in an embodiment of the present utility model, the intermediate portion 112 may also have at least two intermediate reinforcing ribs 1122, such as, but not limited to, the two intermediate reinforcing ribs 1122 shown in the figures. The intermediate reinforcing ribs 1122 are connected between two intermediate side walls 1121, and at least two intermediate reinforcing ribs 1122 are arranged at intervals in the vertical direction. On the basis of this, the inner surface or the outer surface of any one of the intermediate side walls 1121 is used as a reference surface, on which the orthographic projection of the outer side portion 113 occupies only a part of the intermediate side wall 1121 in the height direction Y, the orthographic projection of at least one intermediate reinforcing rib 1122 is located within the orthographic projection range of the outer side portion 113, and the orthographic projection of at least one other intermediate reinforcing rib 1122 is located outside the orthographic projection range of the outer side portion 113. The thickness D6 of the intermediate bead 1122 in the forward projection range of the outer portion 113 may be larger than the thickness D7 of the intermediate bead 1122 in the forward projection range of the outer portion 113. With the above-described structural design, since the portion of the intermediate portion 112 corresponding to the outer portion 113 has a larger impact force when an external impact is applied, the present utility model can further enhance the impact resistance of the portion of the intermediate portion 112 corresponding to the outer portion 113 by using the intermediate bead 1122 having a larger thickness corresponding to the portion.

As shown in fig. 2 and 3, in an embodiment of the present utility model, the inner portion 111 may also have at least two inner reinforcing ribs 1112, such as, but not limited to, the two inner reinforcing ribs 1112 shown in the drawings. The inner reinforcement ribs 1112 are connected between the inner sidewall 1111 and the inner middle sidewall 1121, and at least two inner reinforcement ribs 1112 are arranged at intervals in the vertical direction. On the basis of this, on the reference plane, the orthographic projection of the outer side portion 113 occupies only a part of the inner side wall 1111 in the height direction Y, the orthographic projection of at least one inner side reinforcing rib 1112 is located within the orthographic projection of the outer side portion 113, and the orthographic projection of at least one other inner side reinforcing rib 1112 is located outside the orthographic projection of the outer side portion 113. The thickness D8 of the inner reinforcement ribs 1112 in the forward projection range of the outer portion 113 may be larger than the thickness D9 of the inner reinforcement ribs 1112 in the forward projection range of the outer portion 113. With the above-described structural design, since the portion of the inner side portion 111 corresponding to the outer side portion 113 is larger in impact force when external impact is applied thereto, the present utility model can further enhance the impact resistance of the portion of the inner side portion 111 corresponding to the outer side portion 113 by using the inner side reinforcing ribs 1112 having a larger thickness corresponding to the portion.

As shown in fig. 3, in an embodiment of the present utility model, the middle portion 112 is provided with the middle reinforcing rib 1122, and the inner side portion 111 is provided with the inner reinforcing rib 1112, and the number of the middle reinforcing ribs 1122 is not limited to one or two or more, and the number of the inner reinforcing ribs 1112 is not limited to one or two or more, and the middle reinforcing ribs 1122 and the inner reinforcing ribs 1112 may be arranged to be staggered in the height direction Y. Through the above structural design, the present utility model can make the middle side wall 1121 receive the extrusion force in two opposite directions (i.e. the left and right directions along the first direction X in the drawing), so that the middle portion 112 is more prone to collapse. In contrast, when the middle reinforcing ribs 1122 and the inner reinforcing ribs 1112 are arranged in alignment (i.e., the corresponding middle reinforcing ribs 1122, inner reinforcing ribs 1112 and the middle side wall 1121 connected together form a similar cross-shaped structure together), the forces of the middle reinforcing ribs 1122 and the inner reinforcing ribs 1112 on the middle side wall 1121 are easily offset each other, so that the middle portion 112 is difficult to collapse.

As shown in fig. 3, in an embodiment of the present utility model, the distance H (i.e., the height difference) between the middle reinforcing ribs 1122 and the inner reinforcing ribs 1112, which are offset in the height direction Y, may be smaller than 5mm, for example, 0.5mm, 1mm, 2mm, 3mm, 4.5mm, or the like, due to the structural design in which the middle reinforcing ribs 1122 and the inner reinforcing ribs 1112 are offset in the height direction Y. Through the above structural design, the utility model can avoid the influence of the excessive height difference between the middle reinforcing ribs 1122 and the inner reinforcing ribs 1112 on the structural strength of the frame 110 under the normal working condition of the battery pack. In some embodiments, the distance H between the middle reinforcement 1122 and the inner reinforcement 1112 in the height direction Y may be greater than or equal to 5mm, for example, 5mm, 5.05mm, etc., but is not limited to this embodiment.

As shown in fig. 3, based on the structural design in which the intermediate reinforcing ribs 1122 and the inner reinforcing ribs 1112 are arranged offset in the height direction Y, in an embodiment of the present utility model, the intermediate portion 112 may have two intermediate reinforcing ribs 1122 which are arranged at intervals in the height direction Y, and the inner portion 111 may have two inner reinforcing ribs 1112 which are arranged at intervals in the height direction Y. On this basis, the upper intermediate reinforcing beads 1122 may be located below the upper inner reinforcing beads 1112, and the lower intermediate reinforcing beads 1122 may be located above the lower inner reinforcing beads 1112, in the height direction Y.

Referring to fig. 5, a plan cross-sectional view of a battery case 100 capable of embodying the principles of the present utility model is representatively illustrated in fig. 5 in another exemplary embodiment.

Unlike the structural design in which the intermediate reinforcing beads 1122 extend in a substantially horizontal direction in the embodiment shown in fig. 1 to 4, as shown in fig. 5, still taking a structural design in which the intermediate portion 112 has the intermediate reinforcing beads 1122 as an example, in an embodiment of the present utility model, the intermediate reinforcing beads 1122 may be arranged obliquely with respect to the horizontal plane, whereby the end portion of the intermediate reinforcing beads 1122 connected to the outer intermediate side wall 1121 is made different in height from the end portion connected to the inner intermediate side wall 1121. Through the structural design, the middle part 112 can be more easily collapsed, and the buffering and energy absorbing functions of the middle part 112 are ensured.

As shown in fig. 5, based on the structural design that the middle reinforcing ribs 1122 can be arranged obliquely with respect to the horizontal plane, in an embodiment of the present utility model, the inclination angle α of the middle reinforcing ribs 1122 with respect to the horizontal plane may be 15 ° to 165 °, and not equal to 90 °, such as 15 °, 30 °, 45 °, 60 °, 75 °, 120 °, 135 °, 165 °, etc. Through the above structural design, the utility model can avoid the intermediate reinforcing ribs 1122 from being arranged horizontally to cause the intermediate reinforcing ribs 1122 to be more difficult to collapse, and can avoid the intermediate reinforcing ribs 1122 from being arranged vertically to cause the intermediate reinforcing ribs 1122 to be less obvious in the structural reinforcing function of the intermediate portion 112 due to the overlarge inclination angle alpha of the intermediate reinforcing ribs 1122. In some embodiments, the inclination angle α of the middle stiffener 1122 with respect to the horizontal plane may be less than 15 °, or may be greater than 165 °, such as 15.5 °, 166 °, etc., but is not limited to this embodiment.

It should be noted herein that the battery case 100 shown in the drawings and described in the present specification is merely a few examples of the wide variety of battery cases 100 that can employ the principles of the present utility model. It should be clearly understood that the principles of the present utility model are in no way limited to any of the details or any of the components of the battery case 100 shown in the drawings or described in the present specification.

In summary, the battery case 100 according to the present utility model includes the frame 110, the frame 110 includes the inner portion 111, the middle portion 112 and the outer portion 113, the middle portion 112 has two middle side walls 1121, the inner portion 111 has inner side walls 1111 spaced apart from the inner middle side walls 1121, the outer portion 113 has outer side walls 1131 spaced apart from the outer middle side walls 1121, and the thickness of the middle side walls 1121 is smaller than the thickness of the inner side walls 1111 and smaller than the thickness of the outer side walls 1131. Through the above structural design, when the frame 110 is impacted externally, the two middle side walls 1121 with smaller thickness of the middle portion 112 deform and collapse before the inner side wall 1111 and the outer side wall 1131 with larger thickness, so that the middle portion 112 provides the function of buffering and absorbing energy. In addition, since the ratio of the height of the inner side 111 to the height of the middle 112 is 0.5-1, the present utility model can provide protection for the internal structure of the battery pack by using the inner side wall 1111 which is not collapsed when the two middle side walls 1121 of the middle 112 collapse.

Based on the above detailed description of several exemplary embodiments of the battery case according to the present utility model, an exemplary embodiment of the battery pack according to the present utility model will be described below.

In an embodiment of the present utility model, the battery pack according to the present utility model may include the battery case according to the present utility model and described in detail in the above embodiment. The battery pack can be applied to a vehicle-mounted battery, but is not limited to the battery pack.

It should be noted herein that the battery packs shown in the drawings and described in this specification are only a few examples of the wide variety of battery packs that can employ the principles of the present utility model. It should be clearly understood that the principles of the present utility model are in no way limited to any details or any components of the battery pack shown in the drawings or described in the present specification.

In summary, the battery pack provided by the utility model has the advantages that the battery box provided by the utility model can provide the buffering and energy absorbing functions by utilizing the middle part of the frame, so that the battery damage caused by directly transmitting the impact force to the battery when the battery box is subjected to external impact is avoided, the safety of the battery pack is improved, and the service life is prolonged.

Exemplary embodiments of the battery case and the battery pack according to the present utility model are described and/or illustrated in detail above. Embodiments of the utility model are not limited to the specific embodiments described herein, but rather, components and/or steps of each embodiment may be utilized independently and separately from other components and/or steps described herein. Each component and/or each step of one embodiment may also be used in combination with other components and/or steps of other embodiments. When introducing elements/components/etc. that are described and/or illustrated herein, the terms "a," "an," and "the" are intended to mean that there are one or more of the elements/components/etc. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements/components/etc., in addition to the listed elements/components/etc. Furthermore, the terms "first" and "second" and the like in the claims and in the description are used for descriptive purposes only and not for numerical limitation of their subject matter.

While the utility model has been described in terms of various specific embodiments, those skilled in the art will recognize that the utility model can be practiced with modification within the spirit and scope of the claims.

Claims (11)

1. The battery box body is characterized by comprising a frame, wherein the frame comprises an inner side part, a middle part and an outer side part which are arranged along a first direction, the inner side part and the outer side part are respectively positioned at the inner side and the outer side of the middle part, the inner side part, the middle part and the outer side part are respectively provided with a cavity, the inner side part is level with the bottom of the middle part, the ratio of the height of the inner side part to the height of the middle part is 0.5-1, the middle part is provided with two middle side walls which are arranged at intervals along the first direction, the inner side part is provided with an inner side wall, the inner side wall is positioned at intervals at the inner side of the middle side wall on the inner side, and the outer side part is provided with an outer side wall which is positioned at intervals at the outer side of the middle side wall on the outer side; wherein the thickness of the intermediate side wall is smaller than the thickness of the inner side wall and smaller than the thickness of the outer side wall.

2. The battery compartment of claim 1 wherein the thickness of both of the intermediate side walls is equal.

3. The battery box of claim 1, wherein the thickness of the outer middle sidewall is less than the thickness of the inner middle sidewall.

4. The battery box of claim 1, wherein the middle portion further has at least two middle reinforcing ribs connected between the two middle side walls, the at least two middle reinforcing ribs being arranged at intervals in a vertical direction; and taking the inner surface or the outer surface of any intermediate side wall as a reference surface, wherein on the reference surface, the orthographic projection of the outer side part only occupies a part of the intermediate side wall along the height direction, the orthographic projection of at least one intermediate reinforcing rib is positioned in the orthographic projection range of the outer side part, the orthographic projection of at least one other intermediate reinforcing rib is positioned outside the orthographic projection range of the outer side part, and the thickness of the intermediate reinforcing rib, the orthographic projection of which is positioned in the orthographic projection range of the outer side part, is larger than the thickness of the intermediate reinforcing rib, the orthographic projection of which is positioned in the orthographic projection range of the outer side part.

5. The battery box of claim 1, wherein the inner side portion further has at least two inner side reinforcing ribs connected between the inner side wall and the inner middle side wall, the at least two inner side reinforcing ribs being arranged at intervals in a vertical direction; and taking the inner surface or the outer surface of any intermediate side wall as a reference surface, wherein on the reference surface, the orthographic projection of the outer side part only occupies a part of the inner side wall along the height direction, the orthographic projection of at least one inner side reinforcing rib is positioned in the orthographic projection range of the outer side part, the orthographic projection of at least one other inner side reinforcing rib is positioned outside the orthographic projection range of the outer side part, and the thickness of the inner side reinforcing rib, the orthographic projection of which is positioned in the orthographic projection range of the outer side part, is larger than the thickness of the inner side reinforcing rib, the orthographic projection of which is positioned in the orthographic projection range of the outer side part.

6. The battery box of claim 1, wherein the middle portion further has a middle stiffener connected between the two middle side walls, the inner portion further has an inner stiffener connected between the inner side walls and the inner middle side wall; wherein, the middle reinforcing rib and the inner reinforcing rib are staggered in the height direction.

7. The battery box of claim 6, wherein the middle stiffener is offset from the inner stiffener by a distance of less than 5mm in the height direction.

8. The battery case according to claim 6, wherein the intermediate portion has two of the intermediate reinforcing ribs, the two of the intermediate reinforcing ribs being arranged at intervals in the height direction, the inner portion has two of the inner reinforcing ribs, the two of the inner reinforcing ribs being arranged at intervals in the height direction; wherein, along the direction of height, the top the intermediate strengthening rib is located the top the below of interior side strengthening rib, the below the intermediate strengthening rib is located the below the top of interior side strengthening rib.

9. The battery box of claim 1, wherein the middle portion further has a middle stiffener connected between the two middle side walls, the middle stiffener being disposed obliquely to the horizontal.

10. The battery compartment of claim 9, wherein the intermediate stiffener is inclined at an angle of 15 ° to 165 ° and not equal to 90 ° relative to the horizontal plane.

11. A battery pack comprising the battery case according to any one of claims 1 to 10.