Secondary battery tray and secondary battery

Abstract

Secondary battery tray for receiving a bare cell, characterized in that the secondary battery tray has: a floor wall, where H1 represents a thickness of the floor wall; a side wall, wherein the side wall is connected to the bottom wall, the bottom wall and the side wall together enclose a receiving cavity for receiving the bare cell, H2 represents a thickness of the side wall and L represents a volume of the receiving cavity; where 0.85 mm≤H1≤2.5 mm and 0.35 mm≤H2≤1.5 mm.

Description

TECHNICAL AREA

[0001] This application relates to the field of battery technology, in particular to a secondary battery tray and a secondary battery. BACKGROUND

[0002] Lithium-ion batteries for large-scale applications are classified into three types based on their outer casing: prismatic aluminum case batteries, cylindrical batteries, and pouch batteries. Among these, prismatic aluminum case batteries offer a more competitive price-performance ratio in numerous applications, and the aluminum case structure can provide effective insulation between the battery's internal and external environments. Therefore, aluminum cases are increasingly being used for battery packaging.

[0003] Currently, the aluminum shell structure that houses a bare cell is generally formed through a stamping or drawing process. However, the parameters of the aluminum shell are determined by production capacity, which can lead to poor compatibility with the bare cell and a tendency to crack. SUMMARY OF THE USAGE SAMPLE

[0004] Therefore, it is necessary to provide a secondary battery shell and a secondary battery to solve the problem that an existing aluminum shell structure has poor compatibility with a bare cell and is prone to cracking.

[0005] A secondary battery tray for holding a bare cell comprises a bottom wall and a side wall.

[0006] H1 stands for the thickness of the floor wall;

[0007] The side wall is connected to the bottom wall; the bottom wall and the side wall together enclose a receiving cavity for receiving the bare cell; H2 represents a thickness of the side wall, and L represents a volume of the receiving cavity.

[0008] Here, 0.85 mm≤H1≤2.5 mm and 0.35 mm≤H2≤1.5 mm.

[0009] In one embodiment, the ratio between the thickness H1 of the bottom wall and the volume L of the receiving cavity is 0.3269ln(H1)+0.943≤ L≤ 0.3995In(H1)+1.4825.

[0010] In one embodiment, the side wall comprises two larger side walls spaced apart along a first direction and two smaller side walls spaced apart along a second direction. The two larger side walls are connected end-to-end to the two smaller side walls, and the area dimensions of each larger side wall are greater than the area dimensions of each smaller side wall. H3 represents the thickness of each larger side wall and H4 represents the thickness of each smaller side wall.

[0011] Where 0.35 mm≤H3≤1.05 mm and 0.35 mm≤H4≤1.5 mm.

[0012] In one embodiment, the ratio between the thickness H3 of each larger side wall and the volume L of the receiving cavity is: -0.0038H3 2 +0.0788H3+ 0.3021≤L≤-0.0043H3 2 +0.0888H3+0.5526.

[0013] In one embodiment, the ratio between the thickness H4 of each smaller side wall and the volume L of the receiving cavity is: 0.3884H4 0,4354 ≤ L ≤ 0.8413H4 0,2926 .

[0014] In one embodiment, a first curved section is formed at a transition between each larger side wall and an adjacent smaller side wall; R1 represents an arc radius of the first curved section, wherein 1.5 mm ≤R1 ≤ 3 mm.

[0015] In one embodiment, a projection is arranged on a side of the side wall facing away from the bottom wall, and the projection is configured to extend towards the interior of the receiving cavity; and

[0016] D represents the extension length of the projection that extends into the interior of the receiving cavity, where 0.1 mm ≤ D ≤ 0.3 mm.

[0017] In one embodiment, the projection comprises a transition section and a support section; the transition section is smoothly connected to the side wall; the support section is connected to the transition section and arranged to extend into the interior of the receiving cavity.

[0018] A section of the transition piece cut in the direction of the thickness of the side wall is arc-shaped. Or the transition piece forms an obtuse angle with the side wall, and the transition piece is inclined towards the bottom wall.

[0019] In one embodiment, there are two projections that are opposite to each other and are arranged on two opposite sides of the side wall, each facing the interior of the receiving cavity.

[0020] A secondary battery comprises the secondary battery casing of one of the above-mentioned technical solutions, the bare cell, and a top cover.

[0021] The bare cell is received in the receiving cavity and comprises a positive electrode plate, a negative electrode plate and a separator.

[0022] The top cover is positioned on the secondary battery tray and can seal an open end of the secondary battery tray.

[0023] In the aforementioned secondary battery and secondary battery casing, the bottom wall and side wall together enclose the receiving cavity. The thickness H1 of the bottom wall is set to be between 0.85 mm and 2.5 mm, and the thickness H2 of the side wall is set to be between 0.35 mm and 1.5 mm. By setting the thickness of the bottom and side walls, sufficient structural strength is ensured for the secondary battery casing, preventing it from cracking during packaging and use. When the bare cell is received in the receiving cavity, the secondary battery casing and the bare cell are highly compatible, thus improving the safety performance of the secondary battery. DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a schematic structural view of a secondary battery tray according to some embodiments. Fig. Figure 2 is a front view of the secondary battery tray according to some embodiments. Fig. Figure 3 is a top view of the secondary battery tray according to some embodiments. Fig. 4 is an enlarged partial view of section A in Fig. 1. Fig. Figure 5 is a schematic exploded view of a secondary battery according to some embodiments. Fig. Figure 6 is a diagram showing the trend of the change in volume of a receiving cavity with the thickness of the bottom wall, according to some embodiments. Fig. Figure 7 is a diagram showing a change trend in the volume of the receiving cavity with the thickness of a larger side wall, according to some embodiments. Fig. Figure 8 is a diagram showing a change trend in the volume of the receiving cavity with the thickness of a smaller side wall, according to some embodiments. Fig. Figure 9 is a diagram showing the tendency of the change in the volume of the receiving cavity with the arc radius of a second curved section according to some embodiments. Reference numbers:

[0024] 100, secondary battery tray; 110, bottom wall; 120, side wall; 121, larger side wall; 122, smaller side wall; 130, receiving cavity; 140, first curved section; 150, second curved section; 160, projection; 161, transition section; 162, support section; 200, secondary battery; 210, bare cell; 220, top cover. DETAILED DESCRIPTION OF THE EXECUTION FORMS

[0025] To clarify and make the aforementioned objectives, elements, and advantages of this application more understandable, specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are explained in the following description to fully understand this application. However, this application can be implemented in many other ways that differ from those described herein, and those skilled in the art can make similar improvements without altering the meaning of this application. Therefore, this application is not limited by the specific embodiments disclosed below.

[0026] When the terms “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “top”, “bottom”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc. are used in the description of this application, this merely means that the orientation or position relationships indicated by these terms are based on the orientation or position relationships shown in the accompanying drawings and are intended only to facilitate and simplify the description of this application, rather than to indicate or imply that the specified device or element must have a particular orientation or be designed and operated in a particular orientation, and are therefore not to be understood as a limitation of this application.

[0027] Where the terms “first” and “second”, etc., continue to appear, these terms serve only for descriptive purposes and cannot be understood as indicating a relative significance or as an implicit indication of the number of the specified technical elements. Thus, the elements defined as “first” and “second” may explicitly or implicitly include at least one of these elements. When the description of this application refers to “several”, “several” means at least two, e.g., two, three, etc., unless something else is clearly and explicitly defined.

[0028] When the terms “fastening”, “connection”, “communication”, “fixing”, etc., appear in this application, these terms are to be understood in their broadest sense, e.g., they may refer to a permanent connection, a detachable connection, or an integrated connection; or they may refer to a mechanical connection or an electrical connection; or they may refer to a direct connection or an indirect connection via an intermediate medium; or they may refer to internal communication between two elements or an interaction relationship between two elements, unless otherwise clearly defined. Those skilled in the field may understand the specific meanings of the above terms in this application depending on the specific situations.

[0029] When this application describes a first element as being "above" or "below" a second element, etc., this may mean that the first and second elements are in direct contact or that they are in indirect contact via an intermediary, unless explicitly stated and limited otherwise. The first element being "above," "on top of," or "above" the second element may also mean that the first element is directly above or diagonally above the second element, or it may simply mean that the horizontal height of the first element is greater than that of the second element. The first element being "below," "deeper," or "under" the second element may mean that the first element is directly below or diagonally below the second element, or simply that the horizontal height of the first element is less than that of the second element.

[0030] It should be noted that an element described as being "attached" or "arranged" to another element may lie directly on top of the other element or may include an intermediate element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or it may include an intermediate element. Where applicable, the terms "vertical," "horizontal," "above," "below," "left," "right," and similar expressions used in this application are for illustrative purposes only and are not intended to be the only implementation.

[0031] Technical solutions for embodiments of this application are described below with reference to the attached drawings.

[0032] With reference to Fig. 1, Fig. 2, Fig. 3, Fig. 4 to Fig. 5 This application provides a secondary battery tray 100, and the secondary battery tray 100 is designed to receive a bare cell 210. The secondary battery casing 100 comprises a bottom wall 110 and a side wall 120. The bottom wall 110 is connected to the side wall 120, and the bottom wall 110 and the side wall 120 together enclose a receiving cavity 130 for receiving the bare cell 210. By way of example, H1 represents the thickness of the bottom wall 110, H2 represents the thickness of the side wall 120, and L represents the volume of the receiving cavity 130. The volume L of the receiving cavity 130 is defined as the sum of the capacity of the cavity enclosed by the bottom wall 110 and the side wall 120, the volume of the side wall 120, and the volume of the bottom wall 110, where: 0.85 mm ≤ H1 ≤ 2.5 mm and 0.35 mm ≤ H2 ≤ 1.5 mm.In a specific setup, the thickness H1 of the bottom wall 110 can be one of 0.85 mm, 0.92 mm, 1.0 mm, 1.08 mm, 1.15 mm, 1.22 mm, 1.3 mm, 1.38 mm, 1.45 mm, 1.52 mm, 1.6 mm, 1.68 mm, 1.75 mm, 1.82 mm, 1.9 mm, 1.98 mm, 2.05 mm, 2.12 mm, 2.2 mm, 2.28 mm, 2.35 mm, 2.42 mm and 2.5 mm. The thickness H2 of the side wall 120 can be any of the following: 0.35 mm, 0.42 mm, 0.5 mm, 0.58 mm, 0.65 mm, 0.72 mm, 0.8 mm, 0.88 mm, 0.95 mm, 1.02 mm, 1.1 mm, 1.18 mm, 1.25 mm, 1.32 mm, 1.4 mm, 1.45 mm, and 1.5 mm. However, the thickness H1 of the bottom wall 110 and the thickness H2 of the side wall 120 are not limited to the specific values ​​mentioned above. For example, the thickness H1 of the bottom wall 110 can also be any other value within the range of 0.85 mm to 2.5 mm, and the thickness H2 of the side wall 120 can also be any other value within the range of 0.35 mm to 1.5 mm.Specific values ​​for the thickness H1 of the bottom wall 110 and the thickness H2 of the side wall 120 are not limited in this application.

[0033] The bottom wall 110 and the side wall 120 of the secondary battery tray 100 together enclose the receiving cavity 130, and the thickness H1 of the bottom wall 110 is set to be in the range of 0.85 mm to 2.5 mm, and the thickness H2 of the side wall 120 is set to be in the range of 0.35 mm to 1.5 mm. By appropriately setting the thickness of the bottom wall 110 and the side wall 120, it can be ensured that the secondary battery tray 100 has sufficient structural strength and that it can be prevented from tearing during packaging and use. When the bare cell 210 is received in the receiving cavity 130, the secondary battery shell 100 and the bare cell 210 have a high degree of compatibility, and the secondary battery shell 100 can be prevented from exploding due to excessive internal pressure, thus improving the safety performance of the secondary battery 200.

[0034] In one embodiment, the ratio between the thickness H1 of the bottom wall 110 and the volume L of the receiving cavity 130 is determined with reference to Fig. 1 and Fig. 2: 0.3269ln(H1) + 0.943 ≤ L ≤ 0.3995ln(H1) + 1.4825. The following Table 1 shows the relationship between the volume L of the receiving cavity 130 and the thickness H1 of the bottom wall 110.

[0035] Thus, in Fig. Figure 6 shows a change trend of the volume L of the receiving cavity 130 with the thickness of a bottom wall 110. The volume L of the receiving cavity 130 is appropriately designed according to the thickness H1 of the bottom wall 110 to ensure that the bottom wall 110 can withstand the weight-related pressure and volumetric load from the bare cell 210 in the receiving cavity 130, i.e., that the secondary battery shell 100 has sufficient structural strength and that cracking during packaging and use can be prevented.

[0036] Since the volume L of the receiving cavity 130 must be relatively large, for example, when receiving a large bare cell 210, the thickness H1 of the bottom wall 110 can be chosen to be relatively high to prevent the bottom wall 110 from cracking due to the excessive size and weight of the bare cell 210. Conversely, when receiving a small bare cell 210, since the volume L of the receiving cavity 130 must be relatively small, the thickness H1 of the bottom wall 110 can be chosen to be relatively small. Based on this, and to ensure that the bottom wall 110 has sufficient structural strength, the miniaturization and lightweight design of the secondary battery shell 100 is implemented, thereby reducing the molding costs of the secondary battery shell 100.

[0037] In one embodiment, the side wall 120 comprises with reference to Fig. 1, Fig. 2 to Fig. 3 two larger side walls 121, which run along a first direction (the one in Fig. 1 shown X-direction) are spaced apart and two smaller side walls 122, which extend along a second direction (the one shown in Fig. The two larger side walls 121 are spaced apart from each other (in the Y-direction shown in Figure 1). The two larger side walls 121 are connected end to end to the two smaller side walls 122, and the area dimensions of each large side wall 121 are larger than the area dimensions of each small side wall 122. For example, the two larger side walls 121 are spaced apart along the Y-direction shown in Figure 1. Fig. The two smaller side walls 122 are spaced apart in the X-direction shown in 1, and the two smaller side walls 122 are spaced along the in Fig. The two smaller side walls 122 are spaced apart in the Y-direction shown in Figure 1. Each of the larger side walls 121 is adjacent to and connected to two sides of each larger side wall 121, and each of the larger side walls 121 is adjacent to and connected to two sides of each smaller side wall 122. For example, H3 represents the thickness of each larger side wall 121 and H4 represents the thickness of each smaller side wall 122, where 0.35 mm ≤ H3 ≤ 1.05 mm and 0.35 mm ≤ H4 ≤ 1.5 mm. In a specific setup, the thickness H3 of the larger side wall 121 can be one of 0.35 mm, 0.42 mm, 0.5 mm, 0.58 mm, 0.65 mm, 0.72 mm, 0.8 mm, 0.88 mm, 0.95 mm and 1.05 mm, and the thickness H4 of the smaller side wall 122 can be one of 0.35 mm, 0.42 mm, 0.5 mm, 0.58 mm, 0.65 mm, 0.72 mm, 0.8 mm, 0.88 mm, 0.95 mm, 1.02 mm, 1.1 mm, 1.18 mm, 1.25 mm, 1.32 mm, 1.4 mm, 1.48 mm and 1.5 mm.The thickness H3 of the larger sidewall 121 and the thickness H4 of the smaller sidewall 122 are not limited to the specific values ​​provided above. For example, the thickness H3 of the larger sidewall 121 can also be any other value in the range of 0.35 mm to 1.05 mm, and the thickness H4 of the smaller sidewall 122 can also be any other value in the range of 0.35 mm to 1.5 mm. The specific values ​​of the thickness H3 of the larger sidewall 121 and the thickness H4 of the smaller sidewall 122 are not limited within the scope of this application.

[0038] The thickness H3 of the larger side wall 121 of the secondary battery tray 100 is set to be in the range of 0.35 mm to 1.05 mm, and the thickness H4 of the smaller side wall 122 is set to be in the range of 0.35 mm to 1.5 mm. By reasonably adjusting the thickness of the larger side wall 121 and the smaller side wall 122, it can be ensured that the secondary battery tray 100 has sufficient structural strength and that it is prevented from cracking during packaging and use. When the bare cell 210 is received in the receiving cavity 130, the secondary battery tray 100 and the bare cell 210 exhibit a high degree of compatibility, and the secondary battery tray 100 can be prevented from exploding due to excessive internal pressure, thus improving the safety performance of the secondary battery 200.

[0039] Specifically, with reference to Fig. 1, Fig. 2 to Fig. 3 the ratio between the thickness H3 of each larger side wall 121 and the volume L of the receiving cavity 130: -0.0038H3 2 +0.0788H3+0.3021≤L≤-0.0043H3 2 +0.0888H3+0.5526. The following Table 2 shows the relationship between the volume L of the receiving cavity 130 and the thickness H3 of the larger side wall 121. Table 2 H3 / mm 0,35 0,42 0,5 0,58 0,65 0,72 0,8 0,88 0,95 1,05 L / Liter 0,33-0,58 0,33-0,59 0,34-0,6 0,35-0,6 0,35-0,61 0,36-0,61 0,36-0,62 0,37-0,63 0,37-0,63 0,38-0,64

[0040] Thus, in Fig. Figure 7 shows a change trend of the volume L of the receiving cavity 130 with the thickness H3 of the larger side wall 121. The volume L of the receiving cavity 130 is appropriately designed according to the thickness H3 of the larger side wall 121 to ensure that the larger side wall 121 can withstand the lateral pressure of the bare cell 210 in the receiving cavity 130, so that the secondary battery shell 100 has sufficient structural strength and the secondary battery shell 100 can be protected from cracking during packaging and use.

[0041] Since the volume L of the receiving cavity 130 must be relatively large, for example, when receiving a large bare cell 210, the thickness H3 of the larger side wall 121 can be chosen to be relatively large in order to prevent the larger side wall 121 from being severely compressed and cracking due to the excessive size of the bare cell 210. Conversely, when receiving a small bare cell 210, since the volume L of the receiving cavity 130 must be relatively small, the thickness H3 of the larger side wall 121 can be chosen to be relatively small. Based on this, and ensuring that the larger side wall 121 has sufficient structural strength, the miniaturization and lightweight design of the secondary battery shell 100 are implemented, thereby reducing the molding costs of the secondary battery shell 100.

[0042] Similarly, with reference to Fig. 1, Fig. 2 to Fig. 3 the ratio between the thickness H4 of each smaller side wall 122 and the volume L of the receiving cavity 130: 0.3884H4 0,4354 ≤L≤0.8413H4 0,2926 The following Table 3 shows the relationship between the volume L of the receiving cavity 130 and the thickness H4 of the smaller side wall 122. Table 3 H4 / mm 0,35 0,5 0,65 0,8 0,95 1,1 1,18 1,25 1,4 1,5 L / Liter 0,25-0,62 0,29-0,69 0,32-0,74 0,35-0,79 0,38-0,83 0,4-0,87 0,42-0,88 0,43-0,9 0,45-0,93 0,46-0,95

[0043] Thus, in Fig. Figure 8 shows a change trend of the volume L of the receiving cavity 130 with the thickness H4 of the smaller side wall 122. The volume L of the receiving cavity 130 is appropriately designed according to the thickness H4 of the smaller side wall 122 to ensure that the smaller side wall 122 can withstand the lateral pressure of the bare cell 210 in the receiving cavity 130, so that the secondary battery shell 100 has sufficient structural strength and the secondary battery shell 100 can be protected from cracking during packaging and use.

[0044] Since the volume L of the receiving cavity 130 must be relatively large, for example, when receiving a large bare cell 210, the thickness H4 of the smaller side wall 122 can be chosen to be relatively large in order to prevent the smaller side wall 122 from being severely compressed and cracking due to the excessive size of the bare cell 210. Conversely, when receiving a small bare cell 210, since the volume L of the receiving cavity 130 must be relatively small, the thickness H4 of the smaller side wall 122 can be chosen to be relatively small. Based on this, and ensuring that the smaller side wall 122 has sufficient structural strength, the miniaturization and lightweight design of the secondary battery shell 100 are implemented, thereby reducing the molding costs of the secondary battery shell 100.

[0045] In one embodiment, as described in Fig. 1, Fig. 2 to Fig. As shown in Figure 3, a first curved section 140 is formed at a transition between each larger side wall 121 and an adjacent smaller side wall 122. R1 represents an arc radius of the first curved section 140, where 1.5 mm ≤ R1 ≤ 3 mm. In a specific setup, the arc radius R1 of the first curved section 140 can be one of the following values: 1.5 mm, 1.62 mm, 1.75 mm, 1.88 mm, 2 mm, 2.12 mm, 2.25 mm, 2.38 mm, 2.5 mm, 2.62 mm, 2.75 mm, 2.88 mm, and 3 mm. The arc radius R1 of the first curved section 140 is not limited to the specific values ​​provided above. For example, the arc radius R1 of the first curved section 140 can also be any other value within the range of 1.5 mm to 3 mm. The specific value of the arc radius R1 of the first curved section 140 is not limited in this application.It should be noted that in one embodiment the first curved section 140 is a circular arc surface formed on an outside of the secondary battery shell 100.

[0046] The arc radius R1 of the first bent section 140 is set to be in the range of 1.5 mm to 3 mm. By appropriately adjusting the arc radius of the first bent section 140, the space utilization rate of the secondary battery shell 100 is optimized, and the structural strength of the joined larger side wall 121 and the smaller side wall 122 is improved, allowing for a smooth transition between the larger side wall 121 and the smaller side wall 122. The transition between the larger side wall 121 and the smaller side wall 122 is less susceptible to stress concentration when compressed, thus preventing the casing of the secondary battery 100 from rupturing under the pressure of the bare cell 210.

[0047] In one embodiment, with reference to Fig. 1 and Fig. 2. At the transition between the bottom wall 110 and the side wall 120, a second curved section 150 is formed. R2 denotes an arc radius of the second curved section 150, where: 0.8 mm ≤ R2 ≤ 3 mm. In a specific setup, the arc radius R2 of the second bent section 150 can be one of the following values: 0.8 mm, 0.88 mm, 0.95 mm, 1.02 mm, 1.1 mm, 1.18 mm, 1.25 mm, 1.32 mm, 1.4 mm, 1.5 mm, 1.58 mm, 1.65 mm, 1.75 mm, 1.82 mm, 1.9 mm, 2 mm, 2.08 mm, 2.15 mm, 2.25 mm, 2.32 mm, 2.4 mm, 2.5 mm, 2.58 mm, 2.65 mm, 2.75 mm, 2.82 mm, 2.9 mm, and 3 mm. The arc radius R2 of the second bent section 150 is not limited to the specific values ​​listed above. For example, the arc radius R2 of the second curved section 150 can also be any other value in the range of 0.8 mm to 3 mm, and the specific value of the arc radius R2 of the second curved section 150 is not limited in this application.It should be noted that in this embodiment the second curved section 150 is a circular arc surface formed on an outside of the secondary battery shell 100.

[0048] The arc radius R2 of the second curved section 150 is adjusted to be in the range of 0.8 mm to 3 mm. By appropriately adjusting the arc radius of the second curved section 150, the space utilization rate of the secondary battery shell 100 is optimized, and the structural strength of the connected bottom wall 110 and side wall 120 is improved, allowing for a smooth transition between the bottom wall 110 and the side wall 120. This transition is less susceptible to the adverse phenomenon of stress concentration when compressed, thus preventing the casing of the secondary battery 100 from rupturing due to the pressure of the bare cell 210.

[0049] Furthermore, with reference to Fig. 1 and Fig. 2 the ratio between the arc radius R2 of the second curved section 150 and the volume L of the receiving cavity 130: -0.0099R2 3 +0.0653R2 2 +0.2297R2+0.7564≤L≤ -0.0114R2 3 +0.0752R2 2 +0.2643R2+1.0842. The following Table 4 shows the relationship between the volume L of the receiving cavity 130 and the arc radius R2 of the second curved section 150. Table 4 R2 / mm 0,8 0,95 1,1 1,25 1,5 1,75 2 2,25 2,5 2,75 3 L / Liter 0,98-1,34 1,03-1,4 1,07-1,45 1,13-1,51 1,21-1,61 1,31-1,72 1,4-1,82 1,49-1,93 1,58-2,04 1,68-2,14 1,77-2,25

[0050] Thus, in Fig. Figure 9 shows a change trend of the volume L of the receiving cavity 130 with the arc radius R2 of the second curved section 150. The volume L of the receiving cavity 130 is appropriately designed according to the arc radius R2 of the second curved section 150 of the bottom wall 110 to ensure that the transition between the bottom wall 110 and the side walls 120 can withstand the weight-related pressure and the volumetric load from the bare cell 210 in the receiving cavity 130, i.e., it can be ensured that the secondary battery shell 100 has sufficient structural strength and is protected from cracking during packaging and use.

[0051] In one embodiment, as described in Fig. 1 to Fig. 2, and Fig. As shown in Figure 4, a projection 160 is arranged on a side of the side wall 120 facing away from the bottom wall 110. The projection 160 is configured to extend into the interior of the receiving cavity 130. The projection 160 is configured to support the upper cover 220. When the upper cover 220 is supported on the projection 160, the upper cover 220 can seal the receiving cavity 130. In one embodiment, the projection 160 is arranged on the side of the side wall 120 near the opening end of the receiving cavity 130. D represents an extension length of the projection 160 that extends toward the interior of the receiving cavity 130, where 0.1 mm ≤ D ≤ 0.3 mm. In a specific device, the extension length D of the projection 160, which extends into the interior of the receiving cavity 130, can be 0.1 mm, 0.12 mm, 0.15 mm, 0.18 mm, 0.2 mm, 0.22 mm, 0.25 mm, 0.28 mm or 0.3 mm.The extension length D of the projection 160, which extends into the interior of the receiving cavity 130, is not limited to the specific values ​​provided above. For example, the extension length D of the projection 160, which extends into the interior of the receiving cavity 130, can also be any other value within the range of 0.1 mm to 0.3 mm. The specific value of the extension length D of the projection 160, which extends into the interior of the receiving cavity 130, is not limited within the scope of this application.

[0052] The extension length D of the projection 160, which extends into the interior of the receiving cavity 130, is adjusted to be in the range of 0.1 mm to 0.3 mm. By appropriately controlling the extension length of the projection 160, the structural stability of the upper cover 220 supported by the projection is improved when the upper cover 220 is supported on the projection 160, and the projection 160 does not adversely affect the arrangement of the bare cell 210 in the receiving cavity 130 due to an excessive extension length.

[0053] Specifically, the lead includes 160 with reference to Fig. 1 and Fig. 2, and Fig. 4. A transition section 161 and a support section 162. The transition section 161 is seamlessly connected to the side wall 120, and the support section 162 is connected to the transition section 161. That is, two sides of the transition section 161 are connected to the side wall 120 and the support section 162, respectively, and the support section 162 is configured to extend into the interior of the receiving cavity 130 to support the upper cover 220. A section of the transition section 161 cut in the thickness direction of the side wall 120 is arcuate. Alternatively, the transition section 161 forms an obtuse angle with the side wall 120, and the transition section 161 is inclined towards the bottom wall 110.Regardless of which of the above-mentioned features is chosen for the transition section 161, the transition section 161 can be smoothly connected to the side wall 120 to improve the structural strength of the support section 162 connected to the side wall 120. Furthermore, the transition section 161 is designed to deviate towards the opening end of the receiving cavity 130, so that the upper cover 220 can be easily guided through the opening end into the receiving cavity 130.

[0054] Furthermore, with reference to Fig. 3. Two projections 160 are arranged opposite each other on opposite sides of the side wall 120, each facing the interior of the receiving cavity 130. Thus, the two projections 160 can each support two opposite sides of the upper cover 220. On the one hand, the structural stability of the upper cover 220 supported by the projections 160 can be improved. On the other hand, a relatively small number of projections 160 is required, which can reduce the molding costs of the secondary battery shell 100 and prevents the projections 160 from occupying too much of the interior space of the secondary battery shell 100. Furthermore, the projections 160 do not unduly disrupt the arrangement of the bare cells 210 in the receiving cavity 130.

[0055] Furthermore, this registration, with reference to Fig. 1-2, and Fig.5 also provides a secondary battery 200. The secondary battery 200 comprises the secondary battery shell 100 of one of the above-mentioned technical solutions, the bare cell 210, and a top cover 220. The bare cell 210 is received in a receiving cavity 130. The bare cell 210 comprises a positive electrode sheet, a negative electrode sheet, and a separator. The bare cell 210 is, for example, a core functional component for the energy storage of the secondary battery 200. The bare cell 210 is typically formed by winding or stacking a positive electrode sheet and a negative electrode sheet, with a separator arranged between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet are each provided with a tab.During the charging and discharging process of the secondary battery 200, the positive and negative electrode plates undergo corresponding chemical reactions to achieve the charging and discharging functions and are connected to the terminal tabs, pole posts, and an external device circuit to form a current loop. The top cover 220 is attached to the secondary battery shell 100 by welding, gluing, hot melting, etc., and the top cover 220 seals the opening end of the secondary battery shell 100. When the top cover 220 is in place, it protects the bare cell 210.

[0056] The secondary battery casing 100 of the secondary battery 200 has sufficient structural strength, achieved through the thickness of the bottom wall 110 and the side wall 120. When the bare cell 210 is housed within the secondary battery casing 100, the casing is protected from cracking. Furthermore, the casing of the secondary battery 100 and the bare cell 210 are highly compatible, which can improve the safety performance of the secondary battery 200.

[0057] The embodiments described above can be combined in any way desired. To keep the description brief, not all possible combinations of the technical elements in the embodiments described above are described. However, as long as the combinations of these technical elements are not contradictory, they should be considered to fall within the scope of this specification.

[0058] The embodiments described above are only some implementations of this application, and the description is relatively specific and detailed, but should not be interpreted as limiting the scope of the patent. It should be noted that, for a person skilled in the art, various modifications and improvements could be made without departing from the concept of this application, and that all such modifications and improvements would fall within the scope of protection of this application. The scope of protection of the patent application should therefore be determined according to the attached claims.

[0059] A secondary battery tray and a secondary battery are disclosed. The secondary battery tray comprises a bottom wall and a side wall. H1 represents the thickness of the bottom wall. The side wall is connected to the bottom wall, and the bottom wall and the side wall together enclose a receiving cavity for receiving a bare cell. H2 represents a thickness of the side wall, and L represents a volume of the receiving cavity, where 0.85 mm ≤ H1 ≤ 2.5 mm and 0.35 mm ≤ H2 ≤ 1.5 mm.

Claims

[1] Secondary battery tray for holding a bare cell, characterized by , that the secondary battery tray has: a floor wall, where H1 represents a thickness of the floor wall; a side wall, wherein the side wall is connected to the bottom wall, the bottom wall and the side wall together enclose a receiving cavity for receiving the bare cell, H2 represents a thickness of the side wall and L represents a volume of the receiving cavity; where 0.85 mm≤H1≤2.5 mm and 0.35 mm≤H2≤1.5 mm. [2] Secondary battery tray according to claim 1, wherein a relationship is between the thickness H1 of the bottom wall and the volume L of the receiving cavity: 0.3269ln(H1)+0.943≤L≤0.3995ln(H1)+1.4825. [3] Secondary battery tray according to claim 1, wherein the side wall comprises two larger side walls spaced apart from each other along a first direction, and two smaller side walls spaced apart from each other in a second direction; the two larger side walls are connected end to end with the two smaller side walls, and the area dimensions of each large side wall are larger than the area dimensions of each small side wall; H3 represents a thickness of each larger side wall; and H4 represents a thickness of each smaller side wall; where 0.35 mm≤H3≤1.05 mm and 0.35 mm≤H4≤1.5 mm. [4] Secondary battery tray according to claim 3, wherein a relationship between the thickness H3 of each major side wall and the volume L of the receiving cavity is: −0.0038H32+0.0788H3+0.3021≤L≤−0.0043H32+0.0888H3+0.5526. [5] Secondary battery tray according to claim 3, wherein a relationship between the thickness H4 of each smaller side wall and the volume L of the receiving cavity is: 0.3884H40.4354≤L≤0.8413H40.2926. [6] Secondary battery shell according to claim 3, wherein a first curved section is formed at a transition between each larger side wall and an adjacent smaller side wall; R1 represents an arc radius of the first curved section, wherein 1.5 mm ≤ R1 ≤ 3 mm. [7] Secondary battery tray according to claim 1, comprising a projection arranged on a side of the side wall facing away from the bottom wall, wherein the projection is arranged to extend towards the interior of the receiving cavity; and D represents an extension length of the projection extending into the interior of the receiving cavity, wherein 0.1 mm ≤ D ≤ 0.3 mm. [8] Secondary battery shell according to claim 7, wherein the projection comprises a transition section and a support section; the transition section is smoothly connected to the side wall; the support section is connected to the transition section and is arranged to extend into the interior of the receiving cavity; and a section of the transition section cut in the thickness direction of the side wall is arc-shaped; or the transition section forms an obtuse angle with the side wall, and the transition section is inclined towards the bottom wall. [9] Secondary battery tray according to claim 7, wherein two projections are provided and the two projections are opposite each other and arranged on two opposite sides of the side wall, each opposite the interior of the receiving cavity. [10] Secondary battery comprising: the secondary battery tray according to any one of claims 1 to 9; the bare cell, which is received in the receiving cavity and has a positive electrode plate, a negative electrode plate and a separator; and an upper cover that is positioned on the secondary battery tray and is able to close an opening end of the secondary battery tray.

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