A battery and battery pack

Abstract

This utility model discloses a battery and a battery pack. The battery includes: a casing with a pressure relief hole on its bottom surface; a battery cell disposed inside the casing; and a bottom support plate disposed inside the casing, between the pressure relief hole and the battery cell. The bottom support plate has a first surface and a second surface arranged in parallel, the first surface facing the battery cell and the second surface facing the pressure relief hole; d×s1 / s2=0.5mm~60mm, where d represents the distance between the bottom support plate and the side of the casing, s2 represents the area of ​​the second surface, and s1 represents the projected area of ​​the bottom support plate onto the bottom surface of the casing. This design facilitates the smooth discharge of gas and heat to the pressure relief hole, improving the venting effect, and also prevents gas and heat from flowing back into the battery cell, thereby improving the safety and reliability of the battery.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and more particularly to a battery and battery pack. Background Technology

[0002] With the continuous development of new energy battery technology, battery safety performance is receiving increasing attention. Battery covers are typically equipped with explosion-proof valves. When gas is generated inside the battery due to abnormal operation, it can be released through the explosion-proof valve to prevent major safety accidents. Currently, to rationally plan the venting channel, the explosion-proof valve can be placed on the bottom surface of the casing, and a base plate can be installed between the bottom surface of the casing and the battery cell to support the cell. However, the base plate can affect the venting space around the explosion-proof valve, potentially causing venting obstruction. Utility Model Content

[0003] This utility model provides a battery and battery pack for improving venting efficiency and enhancing the safety and reliability of battery use.

[0004] In a first aspect, embodiments of the present invention provide a battery, comprising:

[0005] The casing has a pressure relief hole on its bottom surface;

[0006] The battery cell is located inside the casing;

[0007] And a bottom support plate, which is located inside the housing and between the pressure relief hole and the battery cell; the bottom support plate has a first surface and a second surface arranged in parallel, with the first surface facing the battery cell and the second surface facing the pressure relief hole;

[0008] Where d×s1 / s2=0.5mm~60mm, d represents the distance between the bottom support plate and the side of the shell, s2 represents the area of ​​the second surface, and s1 represents the orthographic projection area of ​​the bottom support plate onto the bottom surface of the shell.

[0009] Secondly, this utility model provides a battery pack, including: a housing and a battery as described in the first aspect above, the battery being disposed within the housing.

[0010] The beneficial effects of this utility model are as follows:

[0011] The battery and battery pack provided in this embodiment of the utility model have the following characteristics: If d×s1 / s2 is too small, it may be because both s1 / s2 and d are too small. This results in insufficient venting space between the base plate and the casing, and the base plate being too close to the side of the casing. Consequently, the gas and heat generated by the battery cell cannot easily flow to the pressure relief hole, causing the explosion-proof valve to fail to perform its pressure relief function. If d×s1 / s2 is too large, it may be because both s1 / s2 and d are too large. This results in excessive distance between the base plate and the side of the casing, causing gas and heat to easily flow back from the pressure relief hole to the battery cell, which is also detrimental to pressure relief. Therefore, setting d×s1 / s2 to 0.5mm~60mm can facilitate the smooth discharge of gas and heat to the pressure relief hole, improving the venting effect, and can also prevent gas and heat from flowing back to the battery cell, thereby improving the safety and reliability of battery use. Attached Figure Description

[0012] Figure 1 This is a three-dimensional structural diagram of the battery provided in the embodiment of this utility model;

[0013] Figure 2 This is a cross-sectional view of the first type of base plate provided in this embodiment of the present utility model;

[0014] Figure 3 This is a cross-sectional view of the second type of base plate provided in this embodiment of the present utility model;

[0015] Figure 4 This is a cross-sectional view of the third type of base plate provided in this embodiment of the present utility model;

[0016] Figure 5 This is a cross-sectional view of the fourth type of base plate provided in this embodiment of the present utility model;

[0017] Figure 6 This is a cross-sectional view of the fifth type of base plate provided in this embodiment of the present utility model;

[0018] Figure 7 This is a schematic diagram of the structure of a battery pack provided in an embodiment of the present utility model.

[0019] Figure label:

[0020] 10-Shell, 11-Pressure relief hole, 12-Recessed structure, 13-Opening, 20-Battery cell, 30-Bottom support plate, 40-Explosion-proof valve, b0-Bottom surface of the shell, b1-Side surface of the shell, m1-First surface, m2-Second surface, m3-Side surface of the bottom support plate, m31-First section, m32-Second section, m33-Third section, D1-First end, D2-Second end, 110-Box, 120-Battery. Detailed Implementation

[0021] The specific embodiments of a battery and battery pack provided by this utility model will be described in detail below with reference to the accompanying drawings. It should be noted that the described embodiments are only some embodiments of this utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0022] This utility model embodiment provides a battery, such as Figures 1 to 6 As shown, the battery includes: a housing 10, with a pressure relief hole 11 on the bottom surface b0 of the housing 10; a battery cell 20 disposed inside the housing 10; and a bottom support plate 30 disposed inside the housing 10, between the pressure relief hole 11 and the battery cell 20; the bottom support plate 30 has a first surface m1 and a second surface m2 arranged in parallel, the first surface m1 facing the battery cell 20 and the second surface m2 facing the pressure relief hole 11;

[0023] Wherein, d×s1 / s2=0.5mm~60mm, d represents the distance between the bottom support plate 30 and the side surface b1 of the housing 10, s2 represents the area of ​​the second surface m2, and s1 represents the orthogonal projection area of ​​the bottom support plate 30 onto the bottom surface b0 of the housing 10.

[0024] If the section of the base plate 30 parallel to the bottom surface b0 of the shell 10 is called the first section, there will be many first sections. When the first section with the largest area among these first sections is called the largest section, the orthographic projection of the largest section onto the bottom surface b0 of the shell 10 is the orthographic projection of the base plate 30 onto the bottom surface b0 of the shell 10. Therefore, s1 can also represent the area of ​​the largest section.

[0025] If d×s1 / s2 is too small, it may be because both s1 / s2 and d are too small. This would result in insufficient venting space between the base plate 30 and the casing 10, and the base plate 30 being too close to the side b1 of the casing 10. Consequently, the gas and heat generated by the cell 20 would not easily flow to the pressure relief hole 11, preventing the explosion-proof valve 40 from effectively venting pressure. If d×s1 / s2 is too large, it may be because both s1 / s2 and d are too large. This would result in excessive distance between the base plate 30 and the side b1 of the casing 10, making it easy for gas and heat to flow back from the pressure relief hole 11 to the cell 20, which would also hinder pressure relief. Therefore, setting d×s1 / s2 to 0.5mm~60mm can facilitate the smooth discharge of gas and heat to the pressure relief hole 11, improving the venting effect, and also prevent gas and heat from flowing back to the cell 20, thereby improving the safety and reliability of battery use.

[0026] Optionally, the housing 10 is a receiving cavity with an opening 13 at one end, and the battery cell 20 and the bottom support plate 30 are both disposed in the receiving cavity; furthermore, the battery may also include an explosion-proof valve 40, which closes the pressure relief hole 11, so that the gas and heat discharged from the pressure relief hole 11 can be released to the outside through the explosion-proof valve 40, avoiding the accumulation of too much gas and heat inside the battery, thereby improving the safety and reliability of the battery.

[0027] Optionally, d can be set to 0.5mm to 1mm, for example, d can be any value among 0.5mm, 0.6mm, 0.8mm, 1mm, or 0.5mm to 1mm, and can be set according to actual needs. Since d represents the distance between the bottom support plate 30 and the side b1 of the housing 10, the smaller d is, the smaller the distance between the bottom support plate 30 and the side b1 of the housing 10, the better the suppression effect on the backflow of gas and heat from the pressure relief hole 11 to the cell 20 when gas and heat are discharged, and it can also increase the capacity density. However, if d is too small, it will hinder the flow of gas and heat from the side of the cell 20 to the pressure relief hole 11, and if d is too large, it will reduce the suppression effect on the backflow of gas and heat to the cell 20. Therefore, setting d within 0.5mm to 1mm can achieve a good exhaust effect and also suppress the backflow of gas to the cell 20.

[0028] Optionally, s1 / s2 is greater than 1 and less than or equal to 60. Further, s1 / s2 can be from 1.4 to 60, for example, s1 / s2 can be any value among 1.4, 2, 10, 20, 30, 40, 50, 60 or greater than 1 and less than or equal to 60, where s1 can be set to 3500mm. 2 ~12000mm 2 For example, s1 can be set to 3500mm 2 4000mm 2 6000mm 2 8500mm 2 10000mm 2 12000mm 2 Or 3500mm 2 ~12000mm 2 Any value in the range can be set according to actual needs. s2 can be set to 200mm. 2 ~2500mm 2 For example, s2 can be set to 200mm. 2 400mm 2 800mm 2 1000mm 2 1500mm 2 2000mm 2 2500mm 2Or 200mm 2 ~2500mm 2 Any value in the above range can be set according to actual needs. Since s1 / s2 is greater than 1, it means that the area of ​​the second surface m2 is relatively small. In this case, a gas collecting cavity can be formed between the side of the shell 10 and the bottom support plate 30. As s1 / s2 increases, the smaller s2 is, the larger the volume of the gas collecting cavity, the larger the gas storage space, and the better the flow of gas and heat to the pressure relief hole 11, thus the better the pressure relief effect. However, if s1 / s2 is too large, it will cause the area of ​​the second surface m2 to be too small, which may reduce the stability of the bottom support plate 30 supporting the battery cell 20. Therefore, setting s1 / s2 within the above range can achieve both a good exhaust effect and stable support of the bottom support plate 30 for the battery cell 20.

[0029] Optionally, such as Figure 3 As shown, the side surface b1 of the housing 10 has a recessed structure 12. The orthographic projection of the bottom support plate 30 onto the bottom surface b0 of the housing 10 corresponds to the maximum cross-section of the bottom support plate 30. The orthographic projection of the edge of the maximum cross-section onto the side surface b1 of the housing 10 is located within the recessed structure 12. Figure 3 In this configuration, the largest cross-section is the first surface m1, and the edge of the first surface m1 corresponds to the recessed structure 12. This increases the distance between the widest part of the bottom support plate 30 and the shell 10, increasing the value of d, thereby improving the exhaust effect. Furthermore, based on the structural characteristics of the recessed structure 12, it can enhance the suppression effect on the backflow of gas and heat, which also improves the exhaust effect from this perspective.

[0030] Optionally, the following situations may be included when setting the specific shape of the base plate 30:

[0031] Case 1: The orthographic projection of the base plate 30 onto the large surface of the battery is trapezoidal, such as... Figure 2 As shown, Figure 2 The paper surface is parallel to the large surface of the battery, so Figure 2 The shape of the base plate 30 shown is the orthographic projection of the base plate 30 onto the large surface of the battery.

[0032] The base plate 30 also has a side surface m3 connecting the first surface m1 and the second surface m2. The orthographic projection of the side surface m3 onto the large surface of the battery is a straight line. Therefore, the orthographic projection of the base plate 30 onto the large surface of the battery is a trapezoid. When s1 / s2 is greater than 1, it means that the second area is less than the area of ​​the maximum cross-section. Consequently, the area of ​​the first surface m1 is equal to the orthographic projection area of ​​the base plate 30 onto the bottom surface b0 of the housing 10. That is, the first surface m1 is the maximum cross-section. In other words, the side surface m3 at the widest point of the base plate 30 is pointed, such as... Figure 2 As shown within the dashed circle 1 in the diagram.

[0033] This increases the exhaust space between the base plate 30 and the housing 10, improves the pressure relief effect of gas and heat, and simplifies the structure of the base plate 30, reducing the manufacturing difficulty of the base plate 30.

[0034] It should be understood that the "large surface" of a battery refers to the surface with the largest area among all the surfaces in the battery, such as the combined surface. Figure 2 As shown, the large surface of the battery is parallel to the plane formed by the x and z directions.

[0035] Case 2: Figure 4 As shown, the base plate 30 also has a side surface m3 connecting the first surface m1 and the second surface m2. The orthographic projection of the side surface m3 onto the large surface of the battery is a broken line. Within this broken line is a first line segment m31 connected to the second surface m2. Compared to the first end D1 of the first line segment m31 that is away from the second surface m2, the second end D2 of the first line segment m31 that is connected to the second surface m2 is closer to the pressure relief hole 11. Therefore, the first line segment m31 is inclined towards the pressure relief hole 11 from the first end D1 to the second end D2. This increases the venting space between the base plate 30 and the housing 10, improving the pressure relief effect for gas and heat.

[0036] The broken line may also have a second line segment m32 connected to the first surface m1, and the second line segment m32 is also connected to the first line segment m31. The second line segment m32 is parallel to the side surface b1 of the housing 10. The area of ​​the first surface m1 is equal to the orthographic projection area of ​​the bottom support plate 30 onto the bottom surface b0 of the housing 10, that is, the first surface m1 is the largest cross-section. In other words, the side surface m3 of the bottom support plate 30 at its widest point is planar, such as... Figure 4 As shown in the dashed box 2. In this way, the strength of the bottom support plate 30 at the side m3 can be increased, thereby increasing the support stability of the battery cell 20, and of course, it can also improve the flexibility of the design.

[0037] Scenario 3: such as Figure 5 As shown, the base plate 30 also has a side surface m3 connecting the first surface m1 and the second surface m2. The orthographic projection of the side surface m3 onto the large surface of the battery is a broken line. Within this broken line is a first line segment m31 connected to the second surface m2. Compared to the first end D1 of the first line segment m31 that is away from the second surface m2, the second end D2 of the first line segment m31 that is connected to the second surface m2 is closer to the pressure relief hole 11. Therefore, the first line segment m31 is inclined towards the pressure relief hole 11 from the first end D1 to the second end D2. This increases the venting space between the base plate 30 and the housing 10, improving the pressure relief effect for gas and heat.

[0038] The broken line may further include a second line segment m32 and a third line segment m33. The third line segment m33 connects the first line segment m31 and the second line segment m32, and the second line segment m32 is connected to the first surface m1. The third line segment m33 is parallel to the side surface b1 of the housing 10. That is to say, the side surface m3 at the widest point of the bottom support plate 30 is planar, such as... Figure 5 As shown in the dashed box 3. In this way, the strength of the bottom support plate 30 at the side m3 can be increased, thereby increasing the support stability of the battery cell 20 and improving the flexibility of the design.

[0039] Furthermore, the area of ​​the first surface m1 is smaller than the projected area of ​​the base plate 30 onto the bottom surface b0 of the housing 10, meaning the area of ​​the first surface m1 is smaller than the area of ​​the maximum cross-section, thus the maximum cross-section is located between the first surface m1 and the second surface m2. This increases the exhaust space between the side surface m3 of the base plate 30 and the housing 10, facilitating the flow of gas and heat to the pressure relief hole 11, thereby improving the pressure relief effect. Further, the maximum cross-section closest to the first surface m1 is as follows: Figure 5 As shown by the dashed line 4 in the diagram, due to the viewing angle, the largest cross-section closest to the first surface m1 is in Figure 5 The diagram shows a line. The larger the distance k1 between the largest cross-section closest to the first surface m1 and the first surface m1, the larger the space between the second line segment m32 and the side surface b1 of the shell 10. This is more conducive to the flow of gas and heat to the pressure relief hole 11. The distance between the largest cross-section and the first surface m1 can be set to 0.5mm to 1.5mm. For example, the distance between the largest cross-section and the first surface m1 can be set to any value among 0.5mm, 0.8mm, 1.0mm, 1.5mm or 0.5mm to 1.5mm to meet the pressure relief requirements.

[0040] Case 4: Figure 6 As shown, the base plate 30 also has a side surface m3 connecting the first surface m1 and the second surface m2. The orthographic projection of the side surface m3 onto the large surface of the battery is curved, and the orthographic projection of the base plate 30 onto the large surface of the battery is spindle-shaped. In this way, the exhaust space between the side surface m3 of the base plate 30 and the housing 10 can be increased, which facilitates the flow of gas and heat to the pressure relief hole 11, thereby improving the pressure relief effect.

[0041] The areas of the first surface m1 and the second surface m2 can be the same or different. The maximum cross-section is located between the first surface m1 and the second surface m2, as shown in the figure. Figure 6 As shown by the dashed line 5 in the image, due to the viewing angle, the maximum cross-section is... Figure 6The diagram shows a line; the larger the distance k1 between the maximum cross section and the first surface m1, the larger the space between the second line segment m32 and the side surface b1 of the shell 10, which is more conducive to the flow of gas and heat to the pressure relief hole 11. The distance between the maximum cross section and the first surface m1 can be set to 0.5mm to 3mm to meet the pressure relief requirements.

[0042] In practical implementation, the shape of the base plate is not limited to the four cases mentioned above; it can also be a variation of the four cases, which will not be listed here. Furthermore, to simplify the structure of the attached drawings, in... Figure 4 and Figure 5 Only the housing 10 and the base plate 30 are shown in the image. Figure 6 Only the base plate 30 is shown in the image.

[0043] Based on the same inventive concept, this utility model embodiment also provides a battery pack, such as... Figure 7 As shown, the battery pack may include: a housing 110 and a battery 120 as described in the present invention embodiment, wherein the battery 120 is disposed inside the housing 110.

[0044] Of course, in addition to the housing 110 and the battery 120, the battery pack may also include other structures, such as, but not limited to, a battery management system and a charging / discharging interface. The specific configuration can be set according to actual needs, and no specific limitations are made here.

[0045] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A battery, characterized by, include: The housing has a pressure relief hole on its bottom surface; A battery cell, wherein the battery cell is disposed within the housing; And a bottom support plate, which is disposed inside the housing and between the pressure relief hole and the battery cell; the bottom support plate has a first surface and a second surface arranged in parallel, the first surface facing the battery cell and the second surface facing the pressure relief hole; Wherein, d×s1 / s2=0.5mm~60mm, d represents the distance between the bottom support plate and the side of the shell, s2 represents the area of ​​the second surface, and s1 represents the orthographic projection area of ​​the bottom support plate onto the bottom surface of the shell.

2. The battery of claim 1, wherein, d is 0.5mm to 1mm.

3. The battery of claim 1, wherein the cathode comprises a lithium metal oxide. s1 / s2 is greater than 1 and less than or equal to 60.

4. The battery of claim 3, wherein the cathode is a lithium cobalt oxide cathode. The base plate also has a side surface connecting the first surface and the second surface. The orthographic projection of the side surface onto the large surface of the battery is a straight line, and the area of ​​the first surface is equal to the orthographic projection area of ​​the base plate onto the bottom surface of the housing.

5. The battery of claim 3, wherein the cathode comprises a cathode active material, a cathode binder, and a cathode conductive agent. The base plate also has a side surface connecting the first surface and the second surface. The orthographic projection of the side surface onto the large surface of the battery is a broken line. The broken line has a first line segment connected to the second surface. Compared with the first end of the first line segment that is away from the second surface, the second end of the first line segment that is connected to the second surface is closer to the pressure relief hole.

6. The battery of claim 5, wherein the cathode is a lithium cobalt oxide cathode. The broken line also has a second line segment connected to the first surface, and the second line segment is parallel to the side of the housing; the area of ​​the first surface is equal to the orthogonal projection area of ​​the bottom plate onto the bottom surface of the housing.

7. The battery as described in claim 5, characterized in that, The broken line further includes a second line segment and a third line segment, the third line segment connecting the first line segment and the second line segment, the second line segment connecting to the first surface; the third line segment is parallel to the side of the housing; the area of ​​the first surface is smaller than the orthogonal projection area of ​​the base plate onto the bottom surface of the housing.

8. The battery of claim 3, wherein the cathode comprises a lithium cobalt oxide. The base plate also has a side surface connecting the first surface and the second surface. The orthographic projection of the side surface onto the large surface of the battery is a curve, and the orthographic projection of the base plate onto the large surface of the battery is spindle-shaped.

9. The battery according to any one of claims 1-8, characterized in that, The side of the housing has a recessed structure, and the orthographic projection of the bottom plate onto the bottom surface of the housing corresponds to the maximum cross-section of the bottom plate. The orthographic projection of the edge of the maximum cross-section onto the side of the housing is located within the recessed structure.

10. A battery pack, characterized in that, include: The housing and the battery as described in any one of claims 1-9, wherein the battery is disposed within the housing.

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