A battery and a battery pack

Abstract

This utility model discloses a battery and battery pack. By setting an inclined air guide channel in the bottom support plate, and setting the first distance greater than the second distance, the inclined air guide channel is inclined towards the explosion-proof valve. If the first surface is regarded as the upper surface and the second surface as the lower surface, the inclined air guide is inclined from top to bottom towards the explosion-proof valve. In this way, gas and heat can be quickly transferred to the pressure relief hole through the inclined air guide channel, and then discharged through the explosion-proof valve, ensuring timely pressure relief. This solves the problem that the bottom support plate blocks the explosion-proof valve and affects the flow of gas to the explosion-proof valve, thereby improving the safety and reliability of battery use.

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 typically feature explosion-proof valves. When gas is generated inside the battery due to abnormal operation, the gas can be released through the explosion-proof valve to prevent major safety accidents. Currently, to optimize the venting channel, the explosion-proof valve can be placed on the bottom of the casing, with a base plate placed between the bottom of the casing and the battery cell to support the cell. However, the base plate can easily block the explosion-proof valve, affecting the flow of gas from inside the casing to the valve, thus reducing the safety of battery use. Utility Model Content

[0003] This utility model provides a battery and battery pack to solve the problem that the bottom plate easily blocks the explosion-proof valve, affecting the flow of gas inside the casing to the explosion-proof valve.

[0004] In a first aspect, this utility model provides a battery, including: a housing, and a battery cell, a bottom support plate, and an explosion-proof valve located within the housing. The housing is a receiving cavity with an opening at one end, and the battery cell and the bottom support plate are both disposed within the receiving cavity. The bottom surface of the housing has a pressure relief hole, the explosion-proof valve closes the pressure relief hole, and the bottom support plate is disposed between the explosion-proof valve and the battery cell.

[0005] The base plate has a first surface and a second surface that are opposite to each other, with the first surface facing the battery cell and the second surface facing the explosion-proof valve.

[0006] The base plate includes an inclined air guide channel connecting the first surface and the second surface. The inclined air guide channel has a first distance between the center point of the cross section of the first surface and the reference axis, and a second distance between the center point of the cross section of the second surface and the reference axis. The first distance is greater than the second distance. The reference axis is a straight line that passes through the center of the pressure relief hole and is perpendicular to the bottom surface of the housing.

[0007] 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.

[0008] The beneficial effects of this utility model are as follows:

[0009] This utility model provides a battery and battery pack. By setting an inclined air guide channel in the bottom support plate, and setting the first distance greater than the second distance, the inclined air guide channel is inclined towards the explosion-proof valve. If the first surface is regarded as the upper surface and the second surface as the lower surface, the inclined air guide is inclined from top to bottom towards the explosion-proof valve. In this way, gas and heat can be quickly transferred to the pressure relief hole through the inclined air guide channel, and then discharged through the explosion-proof valve, ensuring timely pressure relief. This solves the problem that the bottom support plate blocks the explosion-proof valve and affects the flow of gas to the explosion-proof valve, thereby improving the safety and reliability of battery use. Attached Figure Description

[0010] Figure 1 This is a three-dimensional structural diagram of the battery provided in the embodiment of this utility model;

[0011] Figure 2 This is a cross-sectional view of the battery provided in an embodiment of the present utility model;

[0012] Figure 3 This is a cross-sectional view of the base plate provided in an embodiment of the present utility model;

[0013] Figure 4 This is another cross-sectional view of the base plate provided in this embodiment of the present utility model;

[0014] Figure 5 This is a schematic diagram of the tilt angle of the tilted air guide channel provided in the embodiment of this utility model;

[0015] Figure 6 for Figure 3 Top view of the structure shown;

[0016] Figure 7 This is a schematic diagram of the structure of a battery pack provided in an embodiment of the present utility model.

[0017] Figure label:

[0018] 10-Housing, 11-Pressure relief hole, 12-Opening, 20-Battery cell, 30-Bottom support plate, 31-Inclined air duct, 32-Vertical air duct, 40-Explosion-proof valve, 50-Support component, b0-Bottom surface, b1-First surface, b2-Second surface, d1-First length, d2-Second length, x1-Reference axis, x2-Central axis, A1-Center of pressure relief hole, Q1-Central area, Q2-Transition area, Q3-Edge area, 110-Box, 120-Battery. Detailed Implementation

[0019] 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.

[0020] This utility model embodiment provides a battery, such as Figures 1 to 6 As shown, the battery may include: a housing 10, and a battery cell 20, a bottom support plate 30 and an explosion-proof valve 40 located inside the housing 10. The housing 10 is a receiving cavity with an opening 12 at one end, and the battery cell 20 and the bottom support plate 30 are both disposed in the receiving cavity. The bottom surface b0 of the housing 10 has a pressure relief hole 11, the explosion-proof valve 40 closes the pressure relief hole 11, and the bottom support plate 30 is disposed between the explosion-proof valve 40 and the battery cell 20.

[0021] The base plate 30 has a first surface b1 and a second surface b2 that are opposite to each other, with the first surface b1 facing the battery cell 20 and the second surface b2 facing the explosion-proof valve 40.

[0022] The base plate 30 includes an inclined air guide channel 31 connecting the first surface b1 and the second surface b2. The inclined air guide channel 31 penetrates the base plate 30. The inclined air guide channel 31 has a first distance d1 between the center point of the cross section of the first surface b1 and the reference axis x1, and a second distance d2 between the center point of the cross section of the second surface b2 and the reference axis x1. The first distance d1 is greater than the second distance d2. The reference axis x1 is a straight line passing through the center A1 of the pressure relief hole 11 and perpendicular to the bottom surface b0 of the housing 10.

[0023] Thus, by setting an inclined air guide channel 31 in the base plate 30, and setting the first distance d1 to be greater than the second distance d2, the inclined air guide channel 31 is inclined towards the explosion-proof valve 40. If the first surface b1 is regarded as the upper surface and the second surface b2 is regarded as the lower surface, the inclined air guide is inclined from top to bottom towards the explosion-proof valve 40. In this way, gas and heat can be quickly transferred to the pressure relief hole 11 through the inclined air guide channel 31, and then discharged through the explosion-proof valve 40, ensuring timely pressure relief. This solves the problem that the base plate 30 blocks the explosion-proof valve 40 and affects the flow of gas to the explosion-proof valve 40, thereby improving the safety and reliability of battery use.

[0024] Optionally, one inclined air guide channel 31 may be provided, or multiple inclined air guide channels 31 may be provided; when multiple inclined air guide channels 31 are provided, at least some of the inclined air guide channels 31 may have different inclination angles α, for example: along the direction from the reference axis x1 to the edge of the base plate 30, such as... Figure 3 and Figure 4In the direction pointing to the left from the reference axis x1, or pointing to the right from the reference axis x1, the tilt angle α of each tilted air guide channel 31 shows an increasing trend. That is, in each tilted air guide channel 31, as the distance from the reference axis x1 increases, the tilt angle α of the tilted air guide channel 31 shows an increasing trend. This increasing trend can be a gradual increase or a gradient increase. The difference between the first distance d1 and the second distance d2 is positively correlated with the tilt angle α. It should be understood that the positive correlation between the difference between the first distance d1 and the second distance d2 and the tilt angle α can be understood as: the larger the difference between the first distance d1 and the second distance d2, the larger the tilt angle α, and vice versa. Furthermore, the tilt angle α can be understood as: the angle between the tilted air guide channel 31 and the reference axis x1, such as... Figure 5 As shown.

[0025] Since the reference axis x1 passes through the center A1 of the pressure relief hole 11, the greater the inclination angle α of the inclined air guide channel 31 that is farther away from the reference axis x1, the greater the inclination angle α of the inclined air guide channel 31 that is farther away from the pressure relief hole 11. If the opening of the inclined air guide channel 31 located on the second surface b2 is called the outlet, then the farther away from the pressure relief hole 11, the closer the outlet of the inclined air guide channel 31 is to the pressure relief hole 11. This allows the gas and heat flowing out from the outlet to be transferred to the pressure relief hole 11 more smoothly, that is, to accelerate the transfer of gas and heat to the pressure relief hole 11, thereby realizing the timely discharge of gas and heat through the explosion-proof valve 40.

[0026] The pressure relief hole 11 can be located at a non-central position on the bottom surface b0 of the housing 10, such as... Figure 4 As shown in the figure, the number of inclined air channels 31 located on the left and right sides of the reference axis x1 can be different, or they can be the same; or, the pressure relief hole 11 can be located at the center of the bottom surface b0 of the housing 10, as shown in the figure. Figure 3 As shown in the figure, the number of inclined air guide channels 31 located on the left and right sides of the reference axis x1 is the same, although they can be different. However, regardless of where the pressure relief hole 11 is located on the bottom surface b0 of the housing 10, the inclination angle α of the inclined air guide channel 31 increases with the distance from the reference axis x1.

[0027] Optionally, the cross-sectional area of ​​the inclined air guide channel 31 on the first surface b1 is larger than the cross-sectional area of ​​the inclined air guide channel 31 on the second surface b2. That is, the inclined air guide channel 31 is wide at one end and narrow at the other end, with the wide end facing the battery cell 20. This allows the gas and heat flowing out of the battery cell 20 to enter the inclined air guide channel 31 more effectively, facilitating gas exhaust.

[0028] The difference between the cross-sectional area of ​​the inclined air guide channel 31 on the first surface b1 and the cross-sectional area of ​​the inclined air guide channel 31 on the second surface b2, hereinafter referred to as the area difference, can be set according to factors such as the location and number of inclined air guide channels 31. No specific limitation is made here, so as to facilitate the smoother export of gas and heat to the pressure relief hole 11.

[0029] For example, the inclined venting channel 31 located at the edge of the base plate 30 likely corresponds to the edge of the battery cell 20. The amount of gas and heat discharged from this location may be relatively small. Since there is a certain space between the battery cell 20 and the housing 10, the area difference of the inclined venting channel 31 can be set smaller to reduce manufacturing difficulty. Alternatively, for the inclined venting channel 31 near the pressure relief hole 11, if the number of surrounding inclined venting channels 31 is small, and gas and heat may accumulate at this location from multiple directions, the area difference of the inclined venting channels 31 can be set larger to allow the accumulated gas and heat to be discharged to the pressure relief hole 11 more quickly, preventing excessive accumulation of gas and heat.

[0030] Optionally, the inclined air guide channel 31 extends in a straight line or a curve from the first surface b1 to the second surface b2, wherein... Figure 3 and Figure 4 The example shown is a straight extension; when it extends in a curve, various forms can be adopted, and this utility model is not limited to any particular form. When the inclined air guide channel 31 extends in a straight line, the transmission distance of gas and heat in the inclined air guide channel 31 can be shortened, thereby allowing the gas and heat to be quickly discharged to the pressure relief hole 11; when the inclined air guide channel 31 extends in a curve, the manufacturing difficulty can be reduced, and the design flexibility can be improved.

[0031] Optionally, the distribution of the inclined air channels 31 can be set according to certain rules or arbitrarily. For example, taking the pressure relief hole 11 located at the center of the bottom surface b0 of the housing 10 as an example, the gas and heat released by the battery cell 20 need to be discharged through the pressure relief hole 11. Since the battery cell 20 can be a laminated battery cell or a wound battery cell, the battery cell 20 may release gas and heat from any side, but they will eventually accumulate towards the bottom support plate 30. Therefore, the central region Q1 of the bottom support plate 30 will accumulate more gas and heat compared to the edge region Q3. In this case, more inclined air channels 31 can be arranged in the central region Q1 of the bottom support plate 30, and fewer inclined air channels 31 can be arranged in the edge region Q3, such as... Figure 6 As shown, along the direction from the edge to the center, the cross-sectional pore density of each inclined air guide channel 31 on the first surface b1 increases gradually. This increasing trend can be either gradual or gradient, thereby providing more channels for the large amount of gas and heat accumulated in the central region, facilitating the rapid discharge of gas and heat.

[0032] Alternatively, the edge area of ​​the base plate 30 may also be provided with a number of inclined air channels 31 (not shown in the figure). That is, the inclined air channels 31 are evenly distributed in the cross-sectional holes of the first surface b1. In this way, as gas and heat accumulate from the edge to the center, they are discharged to the pressure relief hole 11 through the numerous inclined air channels 31 at the edge, thereby reducing the amount of gas and heat accumulating towards the center.

[0033] It should be understood that, Figure 3 and Figure 6 In the diagram, Q1 represents the central region, Q3 represents the edge region, and Q2 represents the transition region, which lies between the central region Q1 and the edge region Q3. Figure 3 The structure shown can be viewed as along... Figure 6 The cross-sectional view along the x3 direction of the dashed line.

[0034] Optionally, the base plate 30 may only have an inclined air guide channel 31, such as Figure 4 As shown; or the base plate 30 may include a vertical air channel 32 in addition to the inclined air channel 31, such as Figure 3 As shown, the vertical air guide channel 32 connects the first surface b1 and the second surface b2, so the vertical air guide channel 32 also penetrates the bottom support plate 30; the central axis x2 of the vertical air guide channel 32 is parallel to the reference axis x1. The central axis x2 of the vertical air guide channel 32 can be understood as a straight line passing through the center of the vertical air guide channel 32 and perpendicular to the bottom surface b0 of the housing 10. The vertical air guide channel 32 is symmetrical along the central axis x2; wherein, the vertical air guide channel 32 extends from the first surface b1 to the second surface b2 in a straight line or a curve.

[0035] Furthermore, the vertical air guide channel 32 is correspondingly arranged with the pressure relief hole 11, that is, the orthographic projection of the vertical air guide channel 32 on the bottom surface b0 of the housing 10 overlaps with the pressure relief hole 11. The overlap can be partial or complete. This effectively shortens the transmission distance of gas and heat from the battery cell 20 to the pressure relief hole 11, so that the gas and heat released by the battery cell 20 corresponding to the pressure relief hole 11 can be quickly discharged through the vertical air guide channel 32, avoiding the accumulation of gas and heat.

[0036] Furthermore, the ratio of the sum of the cross-sectional areas of the vertical air guide channels 32 and the inclined air guide channels 31 to the first surface b1 is 5%-50%. For example, the ratio of the sum of the cross-sectional areas of the vertical air guide channels 32 and the inclined air guide channels 31 to the first surface b1 can be any value among 5%, 10%, 20%, 35%, 45%, 50%, or 5%-50%. If this ratio is too large, it will reduce the mechanical strength of the base plate 30, thereby reducing the support capacity of the base plate 30 for the battery cell 20; if this ratio is too small, the number of vertical air guide channels 32 and inclined air guide channels 31 will be too small, thereby reducing the gas and heat discharge effect. Therefore, choosing an appropriate ratio can ensure both good support for the battery cell 20 and rapid gas and heat discharge.

[0037] It should be understood that the sum of the cross-sectional areas of the vertical air guide channel 32 and the inclined air guide channel 31 on the first surface b1 refers to the sum of the cross-sectional areas of all the vertical air guide channels 32 and all the inclined air guide channels 31 on the first surface b1.

[0038] In addition, the following settings can be made for the vertical air guide channel 32:

[0039] The cross-sectional area of ​​the vertical air guide channel 32 on the first surface b1 is greater than the cross-sectional area of ​​the vertical air guide channel 32 on the second surface b2; that is, the vertical air guide channel 32 is wider at one end and narrower at the other, with the wider end facing the battery cell 20. This allows the gas and heat flowing out of the battery cell 20 to better enter the vertical air guide channel 32, facilitating gas exhaust. Alternatively, the difference between the cross-sectional area of ​​the vertical air guide channel 32 on the first surface b1 and the cross-sectional area of ​​the vertical air guide channel 32 on the second surface b2 is less than 200 mm. 2 This indicates that the cross-sectional areas of the vertical air guide channel 32 on the first surface b1 and the second surface b2 are relatively close, which is permissible and helps to reduce the manufacturing difficulty of the vertical air guide channel 32.

[0040] The ratio of the projected area of ​​the vertical air guide channel 32 on the bottom surface b0 of the housing 10 to the area of ​​the pressure relief hole 11 is 50% to 300%. For example, the ratio of the projected area of ​​the vertical air guide channel 32 on the bottom surface b0 of the housing 10 to the area of ​​the pressure relief hole 11 can be any value among 50%, 80%, 100%, 150%, 200%, 250%, 300%, or 50% to 300%. If the ratio is too small, it will affect the venting effect in the early stage of thermal runaway, and the vertical venting channel 32 will be easily blocked. If the ratio is too large, it will reduce the support effect of the bottom support plate 30 at the pressure relief hole 11 on the battery cell 20, and the electrode plates in the battery cell 20 will be easily squeezed out and block the pressure relief hole 11, thus preventing gas and heat from being discharged through the pressure relief hole 11. Therefore, setting the ratio to 50% to 300% can achieve a better venting effect in the early stage of thermal runaway, and can also provide a better support effect for the battery cell 20, avoiding the impact on the discharge of gas and heat.

[0041] Optionally, the battery may also include a support member 50 disposed between the bottom plate 30 and the bottom surface b0 of the housing 10. The support member 50 can support the bottom plate 30, so that there is a gap between the bottom plate 30 and the bottom surface b0 of the housing 10, which facilitates the transfer of gas and heat to the pressure relief hole 11.

[0042] The support member 50 and the base plate 30 can be integrally molded, which increases the stability of the connection between the support member 50 and the base plate 30, thereby increasing the stability of the support for the battery cell 20. Alternatively, the support member 50 and the base plate 30 can be non-integral molded, for example, the support member 50 and the base plate 30 can be manufactured as two independent structures and then assembled together. This allows the support member 50 and the base plate 30 to be manufactured separately, reducing manufacturing difficulty, increasing manufacturing flexibility, avoiding defects in the support member 50 or the base plate 30 that would render the whole product unusable during integral molding, and improving the product yield.

[0043] Furthermore, multiple support members 50 can be provided, and each support member 50 can be evenly distributed to provide stable support for the battery cell 20 and prevent the battery cell 20 from tilting. The specific number and distribution of support members 50 can be designed according to actual needs, and no specific limitation is made here.

[0044] 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.

[0045] 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.

[0046] 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 enclosure comprises a housing, a battery cell, a bottom support plate, and an explosion-proof valve located within the housing. The housing is a receiving cavity with an opening at one end, and the battery cell and the bottom support plate are both disposed within the receiving cavity. The bottom surface of the housing has a pressure relief hole, the explosion-proof valve closes the pressure relief hole, and the bottom support plate is disposed between the explosion-proof valve and the battery cell. The base plate has a first surface and a second surface that are opposite to each other, the first surface facing the battery cell and the second surface facing the explosion-proof valve; The bottom support plate includes an inclined air guide channel connecting the first surface and the second surface. The inclined air guide channel has a first distance between the center point of the cross section of the first surface and the reference axis, and a second distance between the center point of the cross section of the second surface and the reference axis. The first distance is greater than the second distance. The reference axis is a straight line passing through the center of the pressure relief hole and perpendicular to the bottom surface of the housing.

2. The battery of claim 1, wherein, The inclined air guide channel is provided in multiple ways, and the inclination angle of each inclined air guide channel increases in an increasing trend along the direction from the reference axis to the edge of the base plate; the difference between the first distance and the second distance is positively correlated with the inclination angle.

3. The battery of claim 1, wherein the cathode comprises a lithium metal oxide. The cross-sectional area of ​​the inclined air guide channel on the first surface is greater than the cross-sectional area of ​​the inclined air guide channel on the second surface.

4. The battery of claim 1, wherein the cathode comprises a lithium metal oxide. The inclined air guide channel extends in a straight line or curve from the first surface to the second surface.

5. The battery of claim 1, wherein the cathode comprises a lithium metal oxide. The bottom support plate further includes: a vertical air guide channel connecting the first surface and the second surface, the central axis of the vertical air guide channel being parallel to the reference axis; the orthographic projection of the vertical air guide channel onto the bottom surface of the housing overlaps with the pressure relief hole.

6. The battery of claim 5, wherein the cathode is a lithium cobalt oxide cathode. The cross-sectional area of ​​the vertical air guide channel on the first surface is greater than the cross-sectional area of ​​the vertical air guide channel on the second surface.

7. The battery of claim 5, wherein the cathode comprises a lithium cobalt oxide. The ratio of the projected area of ​​the vertical air guide channel on the bottom surface of the housing to the area of ​​the pressure relief hole is 50% to 300%.

8. The battery of claim 5, wherein the cathode comprises a lithium cobalt oxide. The ratio of the sum of the cross-sectional areas of the vertical air guide channel and the inclined air guide channel on the first surface to the first surface is 5%-50%.

9. The battery of any one of claims 1-8, wherein, The battery further includes a support member disposed between the base plate and the bottom surface of the housing.

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

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