Battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery pack. The battery pack comprises a battery box which is provided with a containing cavity and comprises a side frame, the side frame is provided with an inner cavity, and a first through hole and a second through hole which are communicated with the inner cavity are formed in the frame wall, close to the containing cavity, of the side frame; the pressure relief structure is arranged on the side frame, the inner cavity is communicated to the pressure relief structure, and the first through hole is opposite to the pressure relief structure; the isolation structure is arranged in the containing cavity, divides the containing cavity into a first containing space and a second containing space and comprises a first partition plate and a second partition plate which are oppositely arranged in a spaced mode, a pressure relief space is formed between the second partition plate and the first partition plate, and the pressure relief space communicates with the inner cavity through a first through hole and a second through hole; the first battery pack is arranged in the first accommodating space and comprises first single batteries; the second battery pack is arranged in the second accommodating space, the second battery pack comprises a second single battery, and a second explosion-proof valve of the second single battery and a first explosion-proof valve of the first single battery are oppositely arranged and are communicated to the pressure relief space.

Description

Technical Field

[0001] The present disclosure relates to the technical field of batteries, and more particularly, to a battery pack. Background Art

[0002] In order to improve the energy density of the battery pack, two layers of single cells are arranged in the battery box, and the explosion-proof valves of the two layers of single cells need to be connected to the pressure relief structure on the battery box, so that the pressure relief can be realized for both layers of single cells through the pressure relief structure. However, at present, each layer of single cells is provided with its own pressure relief channel connected to the pressure relief structure to realize pressure relief, resulting in low utilization rate of the internal space of the battery pack.

[0003] It should be noted that the information disclosed in the above background art section is only used to enhance the understanding of the background of the present disclosure, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Utility Model

[0004] The purpose of the present disclosure is to overcome the deficiencies of the above related technologies and provide a battery pack.

[0005] According to one aspect of the present disclosure, there is provided a battery pack, comprising:

[0006] A battery box having a receiving cavity, the battery box includes a side frame, the side frame has an inner cavity, and a first through hole and a second through hole are provided on the frame wall of the side frame close to the receiving cavity, and the first through hole and the second through hole communicate with the inner cavity;

[0007] A pressure relief structure provided on the side frame, the inner cavity communicates with the pressure relief structure, and the first through hole is disposed opposite to the pressure relief structure;

[0008] An isolation structure provided in the receiving cavity, the isolation structure divides the receiving cavity into a first receiving space and a second receiving space, the isolation structure includes a first partition and a second partition that are spaced apart and opposite to each other, and a pressure relief space is formed between the second partition and the first partition, and the pressure relief space communicates with the inner cavity through the first through hole and the second through hole;

[0009] A first battery group provided in the first receiving space, the first battery group includes a first single cell;

[0010] A second battery group provided in the second receiving space, the second battery group includes a second single cell, the second explosion-proof valve of the second single cell is disposed opposite to the first explosion-proof valve of the first single cell and communicates with the pressure relief space.

[0011] On the one hand, for the battery pack of the present disclosure, the first explosion-proof valve and the second explosion-proof valve are communicated with the pressure relief space, so that the overheated gas ejected from the first explosion-proof valve and the second explosion-proof valve can be directly ejected into the pressure relief space. Moreover, the pressure relief space, the first through hole and the second through hole, the inner cavity, and the pressure relief structure are communicated, so that the overheated gas ejected into the pressure relief space can pass through the first through hole and the second through hole, and then be ejected into the pressure relief structure through the inner cavity, breaking through the pressure relief structure and ejecting from the pressure relief structure, avoiding affecting other single cells and preventing the battery pack from exploding. On the other hand, the pressure relief space shared by the two layers of battery packs is directly communicated with the inner cavity of the side frame through the first through hole and the second through hole, shortening the transmission path of the overheated gas, improving the transmission efficiency of the overheated gas, preventing the overheated gas from accumulating in the pressure relief space, avoiding affecting other single cells, and realizing directional pressure relief through the pressure relief space and the pressure relief structure on the side frame. On the further hand, the two layers of battery packs share a pressure relief space and a pressure relief channel, which is beneficial to improving the space utilization rate of the accommodation cavity of the battery box, thereby improving the energy density of the battery pack. On the yet another hand, the first through hole is arranged opposite to the pressure relief structure. The second through hole is provided to prevent all the overheated gas from directly ejecting through the first through hole to break through the pressure relief structure, avoiding the temperature of the gas ejected from the pressure relief structure being too high and avoiding affecting the components around the battery pack.

[0012] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and cannot limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings here are incorporated into the specification and constitute a part of this specification, showing the embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0014] Figure 1 It is a schematic structural diagram of an exemplary embodiment of the battery pack of the present disclosure.

[0015] Figure 2 is Figure 1 a schematic structural diagram of an exemplary embodiment of the inner frame wall.

[0016] Figure 3 is Figure 1 a schematic structural diagram of another exemplary embodiment of the inner frame wall.

[0017] Figure 4 is Figure 1 a schematic structural diagram of still another exemplary embodiment of the inner frame wall.

[0018] DESCRIPTION OF THE REFERENCE NUMERALS

[0019] 1. Battery box; 11. Side frame; 111. Inner frame wall; 1111. First through hole; 1112. Second through hole; 112. Outer frame wall; 1121. Third through hole; 113. Inner cavity; 12. Bottom plate; 13. Accommodating cavity; 131. First accommodating space; 132. Second accommodating space; 14. Protection cover;

[0020] 2. Pressure relief structure; 21. Fixed part; 22. Pressure relief part;

[0021] 3. Isolation structure; 31. First partition; 311. First weak part; 32. Second partition; 321. Second weak part; 33. Pressure relief space;

[0022] 4. First battery pack; 41. First single cell; 41a. First bottom wall; 411. First explosion-proof valve;

[0023] 5. Second battery pack; 51. Second single cell; 51a. Second bottom wall; 511. Second explosion-proof valve;

[0024] X. First direction; Y. Second direction; Z. Third direction. Detailed implementation manners

[0025] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. Like reference numerals in the figures denote like or similar structures, and thus their detailed descriptions will be omitted. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0026] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of an icon to another component, these terms are used in this specification only for convenience, for example, according to the directions of the examples described in the accompanying drawings. It can be understood that if the device of the icon is turned upside down, the component described as "upper" will become the component described as "lower". When a structure is "on" another structure, it may mean that a structure is integrally formed on another structure, or that a structure is "directly" disposed on another structure, or that a structure is "indirectly" disposed on another structure through another structure.

[0027] The terms "a", "an", "the", "said" and "at least one" are used to denote the presence of one or more elements / components / etc.; the terms "comprising" and "having" are used to mean an open inclusion and refer to the possibility of the existence of additional elements / components / etc. in addition to the listed elements / components / etc.; the terms "first", "second", "third", etc. are used only as labels and do not limit the quantity of their objects.

[0028] In this application, unless otherwise clearly defined and limited, the term "connected" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral one; it can be directly connected or indirectly connected through an intermediate medium. "And / or" is merely a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this text generally represents an "or" relationship between the associated objects before and after.

[0029] The exemplary embodiments of the present disclosure provide a battery pack. Referring to Figures 1-4 as shown, the battery pack may include a battery box 1, a pressure relief structure 2, an isolation structure 3, a first battery pack 4, and a second battery pack 5; the battery box 1 has a receiving cavity 13, the battery box 1 includes a side frame 11, the side frame 11 has an inner cavity 113, and a first through hole 1111 and a second through hole 1112 are provided on the frame wall of the side frame 11 close to the receiving cavity 13, and the first through hole 1111 and the second through hole 1112 communicate with the inner cavity 113; the pressure relief structure 2 is provided on the side frame 11, the inner cavity 113 communicates with the pressure relief structure 2, and the first through hole 1111 is disposed opposite to the pressure relief structure 2; the isolation structure 3 is provided in the receiving cavity 13, the isolation structure 3 divides the receiving cavity 13 into a first receiving space 131 and a second receiving space 132, the isolation structure 3 includes a first partition 31 and a second partition 32 that are spaced apart and opposite to each other, and a pressure relief space 33 is formed between the second partition 32 and the first partition 31, and the pressure relief space 33 communicates with the inner cavity 113 through the first through hole 1111 and the second through hole 1112; the first battery pack 4 is provided in the first receiving space 131, the first battery pack 4 includes a first single battery 41; the second battery pack 5 is provided in the second receiving space 132, the second battery pack 5 includes a second single battery 51, and the second explosion-proof valve 511 of the second single battery 51 is disposed opposite to the first explosion-proof valve 411 of the first single battery 41 and communicates with the pressure relief space 33.

[0030] For the battery pack of the present disclosure, on the one hand, the first explosion-proof valve 411 and the second explosion-proof valve 511 are connected to the pressure relief space 33, so that the overheated gas ejected from the first explosion-proof valve 411 and the second explosion-proof valve 511 can be directly ejected into the pressure relief space 33. Moreover, the pressure relief space 33, the first through hole 1111 and the second through hole 1112, the inner cavity 113, and the pressure relief structure 2 are connected, so that the overheated gas ejected into the pressure relief space 33 can pass through the first through hole 1111 and the second through hole 1112, and then be ejected through the inner cavity 113 to the pressure relief structure 2, breaking through the pressure relief structure 2 and ejecting from the pressure relief structure 2, avoiding affecting other single batteries and preventing the battery pack from exploding. On the other hand, the pressure relief space 33 shared by the two-layer battery pack is directly connected to the inner cavity 113 of the side frame 11 through the first through hole 1111 and the second through hole 1112, shortening the transmission path of the overheated gas, improving the transmission efficiency of the overheated gas, preventing the overheated gas from accumulating in the pressure relief space 33, avoiding affecting other single batteries, and realizing directional pressure relief through the pressure relief space 33 and the pressure relief structure 2 on the side frame 11. On the further hand, the two-layer battery pack shares a pressure relief space 33 and a pressure relief channel, which is beneficial to improving the space utilization rate of the accommodation cavity 13 of the battery box 1, thereby improving the energy density of the battery pack. On the other hand, the first through hole 1111 is disposed opposite to the pressure relief structure 2. The second through hole 1112 is provided to prevent all the overheated gas from directly ejecting through the first through hole 1111 to break through the pressure relief structure 2, avoiding the temperature of the gas ejected from the pressure relief structure 2 being too high and avoiding affecting the components around the battery pack.

[0031] In the present exemplary embodiment, with reference to Figure 1 as shown, the battery pack may include a battery box 1, and the battery box 1 may be configured as a cuboid structure. Specifically, the battery box 1 may include a bottom plate 12, a protective cover 14 (not shown in the figure), and four side frames 11. The four side frames 11 may include two first side frames and two second side frames. The bottom plate 12 and the protective cover 14 may be configured as rectangles. Two first side frames and two second side frames are disposed around the bottom plate 12. The two first side frames and the two second side frames are connected end to end to form a rectangular frame. The first side frame extends along the first direction X, and the second side frame extends along the second direction Y. A protective cover 14 is disposed on the other side of the two first side frames and the two second side frames opposite to the bottom plate 12, such that the protective cover 14 is disposed opposite to the bottom plate 12. The two first side frames and the two second side frames are connected between the protective cover 14 and the bottom plate 12. The bottom plate 12, the protective cover 14, the two first side frames, and the two second side frames surround to form the accommodation cavity 13 of the battery box 1.

[0032] It should be noted that both the first direction X and the second direction Y are parallel to the bottom plate 12, and the first direction X intersects with the second direction Y. For example, the first direction X is perpendicular to the second direction Y, and the third direction Z is perpendicular to the bottom plate 12, such that the third direction Z is perpendicular to both the first direction X and the second direction Y.

[0033] Referring to Figure 1 As shown, the side frame 11 is provided as a hollow structure, that is, the side frame 11 has a top frame wall and a bottom frame wall arranged oppositely, and inner frame walls 111 and outer frame walls 112 arranged oppositely. The inner frame walls 111 are arranged close to the single battery, and the outer frame walls 112 are arranged far from the single battery. Moreover, the inner frame walls 111 and the outer frame walls 112 are arranged at intervals, such that the side frame 11 has an inner cavity 113. On the frame wall of the side frame 11 close to the accommodation cavity 13, a first through hole 1111 and a second through hole 1112 are provided. The first through hole 1111 and the second through hole 1112 communicate with the inner cavity 113, that is, on the inner frame walls 111 of the side frame 11, the first through hole 1111 and the second through hole 1112 penetrating through to the inner cavity 113 are provided. The first through hole 1111 can be provided as a circular through hole, and the circular through hole can better cooperate with the pressure relief structure 2, that is, the shape of the first through hole 1111 can be adapted to the shape of the pressure relief structure 2. Of course, the first through hole 1111 can also be provided as a rectangular through hole, various polygonal through holes, etc.

[0034] A pressure relief structure 2 is further provided on the side frame 11, and the inner cavity 113 communicates with the pressure relief structure 2. The pressure relief structure 2 can be a weak structure provided on the side frame 11. After the single battery undergoes thermal runaway, high-temperature gases, sparks, and high-temperature solid particulate matters can break through the pressure relief structure 2 on the side frame 11 and spray out from the pressure relief structure 2, avoiding affecting other single batteries and preventing the battery pack from exploding.

[0035] In the present exemplary embodiment, referring to Figure 1 As shown, the pressure relief structure 2 can include a fixing portion 21 and a pressure relief portion 22. The fixing portion 21 surrounds the outer periphery of the pressure relief portion 22, and the thickness of the pressure relief portion 22 is less than the thickness of the fixing portion 21, ensuring the connection strength between the pressure relief structure 2 and the outer frame wall 112 while ensuring that the pressure relief portion 22 can relieve pressure smoothly. The fixing portion 21 can be fixedly connected to the outer frame wall 112 by screws, and the fixing portion 21 can also be fixedly connected to the outer frame wall 112 by welding, thereby fixedly connecting the pressure relief structure 2 to the outer frame wall 112.

[0036] Of course, in some other exemplary embodiments of the present disclosure, the pressure relief structure 2 may be a scratch or a groove provided on the outer frame wall 112 of the side frame 11; the scratch and the groove structure of the pressure relief structure 2 may be provided on the inner side surface of the outer frame wall 112 close to the single battery, or may be provided on the outer side surface of the outer frame wall 112 facing away from the single battery. The scratch may be formed by machining, and the groove may be formed by photolithography or chemical etching. It may also be a weak structure where the thickness of the entire pressure relief structure 2 is thinner than that of other positions.

[0037] In the present exemplary embodiment, referring to Figure 1 As shown, the pressure relief structure 2 is fixed to the frame wall of the side frame 11 facing away from the accommodation cavity 13, that is, the pressure relief structure 2 is fixed to the outer frame wall 112; a third through hole 1121 is provided on the frame wall of the side frame 11 facing away from the accommodation cavity 13, that is, the third through hole 1121 is provided on the outer frame wall 112, and the third through hole 1121 penetrates through to the inner cavity 113. At least a part of the pressure relief structure 2 is disposed opposite to the third through hole 1121. For example, the entire pressure relief structure 2 may be disposed opposite to the third through hole 1121, or the pressure relief portion 22 of the pressure relief structure 2 for pressure relief may be disposed opposite to the third through hole 1121, and the fixing portion 21 for fixing is not disposed opposite to the third through hole 1121; thus, the inner cavity 113 is communicated to the pressure relief structure 2.

[0038] Moreover, the ratio of the opening area of the third through hole 1121 to the opening area of the first through hole 1111 is greater than or equal to 0.5 and less than 1. For example, the ratio of the opening area of the third through hole 1121 to the opening area of the first through hole 1111 may be 0.53, 0.55, 0.58, 0.6, 0.62, 0.65, 0.67, 0.7, 0.73, 0.75, 0.78, 0.8, 0.82, 0.85, 0.87, 0.9, 0.93, 0.95, 0.98, etc., that is, the opening area of the third through hole 1121 is smaller than the opening area of the first through hole 1111.

[0039] Due to the overheated gas being ejected from the pressure relief space 33 through the first through-hole 1111 and the second through-hole 1112 into the inner cavity 113 and finally ejected to the pressure relief structure 2 at the third through-hole 1121, both the pressure relief space 33 and the inner cavity 113 have a certain cooling and flow splitting effect on the overheated gas, so that the amount of overheated gas finally ejected to the pressure relief structure 2 in the third through-hole 1121 will be reduced to a certain extent. Setting the opening area of the third through-hole 1121 to be smaller than the opening area of the first through-hole 1111 can meet the ejection requirements of the overheated gas. Moreover, since the third through-hole 1121 is provided on the outer frame wall 112 of the side frame 11, and the outer frame wall 112 needs to resist external extrusion and impact, the strength requirement of the outer frame wall 112 is higher than that of the inner frame wall 111. Setting the opening area of the third through-hole 1121 to be smaller can reduce the impact on the strength of the outer frame wall 112 to ensure the strength requirement of the outer frame wall 112.

[0040] If the ratio of the opening area of the third through-hole 1121 to the opening area of the first through-hole 1111 is too small, resulting in the opening area of the third through-hole 1121 being too small to meet the emission requirements of the overheated gas, causing the overheated gas to accumulate in the inner cavity 113 and affecting the safety of the battery pack. The above numerical range can meet the emission requirements of the overheated gas, enabling the overheated gas to be discharged in time to ensure the safety of the battery pack.

[0041] In the present exemplary embodiment, as shown in Figure 1 a separation structure 3 is provided in the accommodation cavity 13, and the separation structure 3 is disposed substantially parallel to the bottom plate 12; the separation structure 3 divides the accommodation cavity 13 into a first accommodation space 131 and a second accommodation space 132. Specifically, the space between the separation structure 3 and the protection cover 14 is the first accommodation space 131, and the space between the separation structure 3 and the bottom plate 12 is the second accommodation space 132. When the bottom plate 12 is used as a support to support the single battery, the first accommodation space 131 and the second accommodation space 132 are arranged vertically. Moreover, the separation structure 3 can be used to support the first battery pack 4 located above.

[0042] A pressure relief space 33 is provided in the separation structure 3, and the pressure relief space 33 is communicated with the inner cavity 113 through the first through-hole 1111 and the second through-hole 1112, that is, the pressure relief space 33, the first through-hole 1111, the second through-hole 1112, and the inner cavity 113 are sequentially communicated and connected to the pressure relief structure 2.

[0043] A first battery pack 4 is provided in the first accommodation space 131, and the first battery pack 4 may include a first single battery 41.

[0044] In this example embodiment, the first single battery 41 may be a cylindrical battery, and the first single battery 41 may include a first battery shell, and the first battery shell may be set as a cylinder, that is, the first battery shell may include a first cover plate and a first bottom wall 41a arranged opposite to each other, and the first cover plate and the first bottom wall 41a are both arranged in a circular shape, and a first side wall is connected between the first cover plate and the first bottom wall 41a, and the first side wall is arranged in a cylindrical shape. The first side wall, the first cover plate and the first bottom wall 41a surround and form a storage space for the first single battery 41, and a battery cell is arranged in the storage space of the first battery shell. Of course, the first single battery 41 may also be a quadrangular prism battery, a pentagonal prism battery, a hexagonal prism battery, and the like.

[0045] The material of the first battery shell can be aluminum, steel or other metal and alloy materials. Of course, it can also be other materials, which are not described here one by one.

[0046] The first single battery 41 is provided with a first explosion-proof valve 411. Figure 1 As shown, a first explosion-proof valve 411 is provided on the first bottom wall 41a. The first explosion-proof valve 411 may be a weak structure provided on the first bottom wall 41a. After thermal runaway of the battery cell occurs, high-temperature gas, sparks and high-temperature solid particles may break through the first explosion-proof valve 411 on the first bottom wall 41a and spray out from the first explosion-proof valve 411 to prevent the first single battery 41 from exploding.

[0047] Specifically, the first explosion-proof valve 411 can be a scratch or groove set on the first bottom wall 41a; the first explosion-proof valve 411 with a scratch or groove structure can be set on the inner side of the first bottom wall 41a close to the battery cell, or can be set on the outer side of the first bottom wall 41a away from the battery cell. The scratch can be formed by mechanical processing, and the groove can be formed by photolithography or chemical etching. It can also be a weak structure in which the thickness of the entire first explosion-proof valve 411 is thinner than the thickness at other locations. In this example embodiment, the first explosion-proof valve 411 is a circular scratch set on the first surface.

[0048] A second battery pack 5 is disposed in the second accommodation space 132 , and the second battery pack 5 may include a second single battery 51 .

[0049] In this exemplary embodiment, the second single battery 51 can be a cylindrical battery. The second single battery 51 can include a second battery case. The second battery case can be set as a cylinder, that is, the second battery case can include a second cover plate and a second bottom wall 51a which are oppositely arranged. Both the second cover plate and the second bottom wall 51a are set as circular. A second side wall is connected between the second cover plate and the second bottom wall 51a. The second side wall is set as a cylindrical shape. The second side wall, the second cover plate and the second bottom wall 51a surround to form an accommodation space of the second single battery 51. An electric core is arranged in the accommodation space of the second battery case. Of course, the second single battery 51 can also be a quadrangular prism battery, a pentagonal prism battery, a hexagonal prism battery, etc.

[0050] The material of the second battery case can be aluminum, steel or other metal and alloy materials. Of course, it can also be other materials, which will not be elaborated one by one here.

[0051] A second explosion-proof valve 511 is arranged on the second single battery 51. Specifically, referring to Figure 1 as shown, the second explosion-proof valve 511 is arranged on the second bottom wall 51a. The second explosion-proof valve 511 can be a weak structure arranged on the second bottom wall 51a. After the electric core has a thermal runaway, high-temperature gas, sparks and high-temperature solid particulate matters can break through the second explosion-proof valve 511 on the second bottom wall 51a and spray out from the second explosion-proof valve 511, preventing the second single battery 51 from exploding.

[0052] Specifically, the second explosion-proof valve 511 can be a scratch or a groove arranged on the second bottom wall 51a. The second explosion-proof valve 511 with a scratch or groove structure can be arranged on the inner side of the second bottom wall 51a close to the electric core, or on the outer side of the second bottom wall 51a facing away from the electric core. The scratch can be formed by machining, and the groove can be formed by photolithography or chemical etching. It can also be a weak structure where the thickness of the entire second explosion-proof valve 511 is thinner than that of other positions. In this exemplary embodiment, the second explosion-proof valve 511 is a circular scratch arranged on the second surface.

[0053] The second explosion-proof valve 511 of the second single battery 51 is disposed opposite to the first explosion-proof valve 411 of the first single battery 41. Specifically, the second bottom wall 51a is disposed directly opposite to the first bottom wall 41a, and the second explosion-proof valve 511 is also disposed directly opposite to the first explosion-proof valve 411. Moreover, the first explosion-proof valve 411 and the second explosion-proof valve 511 communicate with the pressure relief space 33, so that the overheated gas ejected from the first explosion-proof valve 411 and the second explosion-proof valve 511 can be directly ejected into the pressure relief space 33. Moreover, the four structures of the pressure relief space 33, the first through hole 1111 and the second through hole 1112, the inner cavity 113, and the pressure relief structure 2 are connected in sequence. The first through hole 1111 and the second through hole 1112 form a pressure relief channel with the inner cavity 113, so that the overheated gas ejected into the pressure relief space 33 can pass through the first through hole 1111 and the second through hole 1112 and the inner cavity 113 in sequence and be ejected to the pressure relief structure 2, breaking through the pressure relief structure 2 and ejecting from the pressure relief structure 2, avoiding affecting other single batteries and preventing the battery pack from exploding.

[0054] Moreover, the pressure relief space 33 shared by the two-layer battery pack is directly connected to the inner cavity 113 of the side frame 11 through the first through hole 1111 and the second through hole 1112, shortening the transmission path of the overheated gas, improving the transmission efficiency of the overheated gas, preventing the overheated gas from accumulating in the pressure relief space 33, avoiding affecting other single batteries, and realizing directional pressure relief through the pressure relief space 33 and the pressure relief structure 2 on the side frame 11.

[0055] Furthermore, the two-layer battery pack shares a pressure relief space 33 and a pressure relief channel, which is beneficial to improving the space utilization rate of the accommodation cavity 13 of the battery box 1, thereby improving the energy density of the battery pack.

[0056] The first through hole 1111 is located within the orthographic projection of the pressure relief space 33 on the side frame 11. For example, a part of the edge line of the orthographic projection of the pressure relief space 33 on the side frame 11 close to the bottom plate 12 may coincide with the edge line of the first through hole 1111 close to the bottom plate 12, and a part of the edge line of the orthographic projection of the pressure relief space 33 on the side frame 11 far from the bottom plate 12 may coincide with the edge line of the first through hole 1111 far from the bottom plate 12. It is also possible that the orthographic projection of the pressure relief space 33 on the side frame 11 covers and is larger than the first through hole 1111. With such a setting, it is avoided that the first through hole 1111 communicates with the first accommodation space 131 and the second accommodation space 132, ensuring the airtightness of the first accommodation space 131 and the second accommodation space 132.

[0057] The first through-hole 1111 is disposed opposite to the pressure relief structure 2. Optionally, the orthographic projection of the pressure relief structure 2 on the frame wall of the side frame 11 close to the accommodation cavity 13 is directly opposite to the first through-hole 1111, that is, the first through-hole 1111 is directly opposite to the pressure relief structure 2, so that most of the overheated gas injected into the inner cavity 113 through the first through-hole 1111 can be directly ejected to the pressure relief structure 2, further shortening the transmission path of the overheated gas, improving the transmission efficiency of the overheated gas, and preventing the overheated gas from accumulating in the inner cavity 113. Moreover, the setting of the second through-hole 1112 can prevent all the overheated gas from directly ejecting to the pressure relief structure 2 through the first through-hole 1111 and breaking through the pressure relief structure 2, avoid the temperature of the gas ejected from the pressure relief structure 2 being too high, and avoid affecting the components around the battery pack.

[0058] In the present exemplary embodiment, referring to Figure 2 and Figure 3 as shown, the second through-hole 1112 can be set as an oval hole, which is convenient for preparation; of course, the second through-hole 1112 can also be set as a circular through-hole, a rectangular through-hole, various polygonal through-holes, and so on.

[0059] The pressure relief space 33 communicates with the inner cavity 113 through the first through-hole 1111 and the second through-hole 1112. The second through-hole 1112 can increase the path of the overheated gas ejected from the pressure relief space 33 to the inner cavity 113, improve the transmission efficiency of the overheated gas, prevent the overheated gas from accumulating in the pressure relief space 33, and avoid affecting other single cells.

[0060] Optionally, the second through-hole 1112 can be set as multiple, and the total opening area of the multiple second through-holes 1112 is greater than the opening area of the first through-hole 1111. Affected by the height of the pressure relief space 33, the diameter of the first through-hole 1111 cannot be set too large, resulting in a small opening area of the first through-hole 1111. Setting multiple second through-holes 1112 with a larger total opening area can further increase the path of the overheated gas ejected from the pressure relief space 33 to the inner cavity 113, further improve the transmission efficiency of the overheated gas, prevent the overheated gas from accumulating in the pressure relief space 33, and avoid affecting other single cells.

[0061] Referring to Figure 2 as shown, in the first direction X, the distance K1 between two adjacent second through-holes 1112 is greater than or equal to 50 mm and less than or equal to 300 mm. For example, the distance K1 between two adjacent second through-holes 1112 can be 80 mm, 100 mm, 120 mm, 150 mm, 170 mm, 200 mm, 230 mm, 250 mm, 280 mm, and so on. The distance K1 between two adjacent second through-holes 1112 refers to the width of the remaining inner frame wall 111 between two adjacent second through-holes 1112.

[0062] If the spacing K1 between two adjacent second through-holes 1112 is too large, the number of second through-holes 1112 that can be provided on the inner frame wall 111 is too small. As a result, the total opening area of the second through-holes 1112 is too small, which has little effect on increasing the path for the overheated gas to be ejected from the pressure relief space 33 into the inner cavity 113, cannot effectively improve the transmission efficiency of the overheated gas, and easily causes the overheated gas to accumulate in the pressure relief space 33, affecting other single cells.

[0063] If the spacing between two adjacent second through-holes 1112 is too small, the strength of the inner frame wall 111 is too low to meet the function of supporting and protecting the single cell.

[0064] The above numerical range not only enables the total opening area of the second through-holes 1112 to increase the path for the overheated gas to be ejected from the pressure relief space 33 into the inner cavity 113, improves the transmission efficiency of the overheated gas, prevents the overheated gas from accumulating in the pressure relief space 33, and avoids affecting other single cells; but also enables the strength of the inner frame wall 111 to be sufficient to meet the function of supporting and protecting the single cell.

[0065] In the first direction X, the spacing K2 between the second through-hole 1112 and the first through-hole 1111 is greater than or equal to 25 mm and less than or equal to 150 mm. For example, the spacing K2 between the second through-hole 1112 and the first through-hole 1111 can be 50 mm, 80 mm, 100 mm, 120 mm, etc. The spacing K2 between the second through-hole 1112 and the first through-hole 1111 refers to the width of the inner frame wall 111 remaining between the second through-hole 1112 and the first through-hole 1111.

[0066] If the spacing K2 between the second through-hole 1112 and the first through-hole 1111 is too large, the number of second through-holes 1112 that can be provided on the inner frame wall 111 is too small. As a result, the total opening area of the second through-holes 1112 is too small, which has little effect on increasing the path for the overheated gas to be ejected from the pressure relief space 33 into the inner cavity 113, cannot effectively improve the transmission efficiency of the overheated gas, and easily causes the overheated gas to accumulate in the pressure relief space 33, affecting other single cells.

[0067] If the spacing K2 between the second through-hole 1112 and the first through-hole 1111 is too small, the strength of the inner frame wall 111 is too low to meet the function of supporting and protecting the single cell.

[0068] The above numerical range not only enables the total opening area of the second through-holes 1112 to increase the path for the overheated gas to be ejected from the pressure relief space 33 into the inner cavity 113, improves the transmission efficiency of the overheated gas, prevents the overheated gas from accumulating in the pressure relief space 33, and avoids affecting other single cells; but also enables the strength of the inner frame wall 111 to be sufficient to meet the function of supporting and protecting the single cell.

[0069] Referring to Figure 2 and Figure 3 As shown, a plurality of second through-holes 1112 are arranged in a column along the first direction X, and at least two columns of second through-holes 1112 are arranged along the third direction Z. For example, two columns of second through-holes 1112 can be arranged along the third direction Z, or three or more columns of second through-holes 1112 can be arranged along the third direction Z. Setting the second through-holes 1112 to at least two columns enables the width of the second through-holes 1112 to be set smaller, so that the influence of the second through-holes 1112 on the strength of the inner frame wall 111 is smaller, and the total opening area of the second through-holes 1112 can meet the requirement of improving the transmission efficiency of overheated gas; furthermore, when the first single battery 41 in the upper first battery pack 4 overheats, the overheated gas can be discharged through a column of second through-holes 1112 close to the first battery pack 4, and when the second single battery 51 in the lower second battery pack 5 overheats, the overheated gas can be discharged through a column of second through-holes 1112 close to the second battery pack 5; thus, shortening the transmission path of the overheated gas, improving the transmission efficiency of the overheated gas, preventing the overheated gas from accumulating in the accommodation space, and avoiding affecting other single batteries.

[0070] Moreover, referring to Figure 2 As shown, the second through-holes 1112 in adjacent two columns are arranged oppositely, that is, the second through-holes 1112 in adjacent two columns are directly opposite to each other. With such an arrangement, the overheated gas can be discharged more concentratedly into the inner cavity 113.

[0071] Of course, in some other exemplary embodiments of the present disclosure, referring to Figure 3 As shown, the second through-holes 1112 in adjacent two columns can also be arranged in a staggered manner. For example, the adjacent two columns are the first column and the second column respectively, and the second through-holes 1112 in the first column are arranged opposite to the inner frame wall 111 remaining between two adjacent second through-holes 1112 in the second column. With such an arrangement, not only can the width of the second through-holes 1112 in the third direction Z be set wider, further increasing the total opening area of the second through-holes 1112, increasing the path for the overheated gas to be ejected from the pressure relief space 33 into the inner cavity 113, improving the transmission efficiency of the overheated gas, preventing the overheated gas from accumulating in the pressure relief space 33, and avoiding affecting other single batteries; moreover, the influence on the strength of the inner frame wall 111 is smaller, and the strength requirement of the inner frame wall 111 can be ensured.

[0072] Moreover, the second through-hole 1112 is located within the orthographic projection of the pressure relief space 33 on the side frame 11. For example, it can be that a part of the edge along the bottom plate 12 of the orthographic projection of the pressure relief space 33 on the side frame 11 coincides with the edge along the bottom plate 12 of the second through-hole 1112, and a part of the edge away from the bottom plate 12 of the orthographic projection of the pressure relief space 33 on the side frame 11 coincides with the edge away from the bottom plate 12 of the second through-hole 1112; it can also be that the orthographic projection of the pressure relief space 33 on the side frame 11 covers and is larger than the second through-hole 1112. With such a setting, it is avoided that the second through-hole 1112 communicates with the first accommodation space 131 and the second accommodation space 132, ensuring the tightness of the first accommodation space 131 and the second accommodation space 132.

[0073] Refer to Figure 1 As shown, in the third direction Z, the distance H between two adjacent columns of the second through-holes 1112 is greater than 0 and less than or equal to 15 mm. For example, the distance H between two adjacent columns of the second through-holes 1112 can be 3 mm, 5 mm, 8 mm, 10 mm, 12 mm, etc. The distance H between two adjacent columns of the second through-holes 1112 refers to the width of the remaining inner frame wall 111 between two adjacent columns of the second through-holes 1112 in the third direction Z.

[0074] If the distance H between two adjacent columns of the second through-holes 1112 is too large, the width of the second through-hole 1112 in the third direction Z is set too small, so that the total opening area of the second through-hole 1112 is too small, which has little effect on increasing the path for the overheated gas to be ejected from the pressure relief space 33 to the inner cavity 113, cannot improve the transmission efficiency of the overheated gas well, and easily causes the overheated gas to accumulate in the pressure relief space 33, affecting other single cells.

[0075] The above numerical range enables the width of the second through-hole 1112 in the third direction Z to be set wider, and the total opening area of the second through-hole 1112 can increase the path for the overheated gas to be ejected from the pressure relief space 33 to the inner cavity 113, improve the transmission efficiency of the overheated gas, prevent the overheated gas from accumulating in the pressure relief space 33, and avoid affecting other single cells.

[0076] In addition, when the second through-holes 1112 in two adjacent columns are arranged in a staggered manner, in the third direction Z, the distance between two adjacent columns of the second through-holes 1112 can be set smaller, and the strength requirement of the inner frame wall 111 can also be ensured; the width of the second through-hole 1112 in the third direction Z can be set larger. When the second through-holes 1112 in two adjacent columns are arranged opposite to each other, in the third direction Z, the distance between two adjacent columns of the second through-holes 1112 can be set larger to ensure the strength requirement of the inner frame wall 111.

[0077] Refer to Figure 4As shown, in some exemplary embodiments of the present disclosure, only one column of second through holes 1112 may be provided, and the width of the second through holes 1112 in the third direction Z may be set to be relatively large.

[0078] In the present exemplary embodiment, the isolation structure 3 may include a first partition 31 and a second partition 32; the second partition 32 is spaced apart from and opposite to the first partition 31, and a pressure relief space 33 is formed between the second partition 32 and the first partition 31.

[0079] The first partition 31 is arranged parallel to the bottom plate 12, and a plurality of first weak parts 311 are provided on the first partition 31. One first weak part 311 is arranged opposite to the first explosion-proof valve 411 of one first single cell 41. The first weak part 311 may be a through hole, so that the first explosion-proof valve 411 is not covered by the first partition 31, so that the first explosion-proof valve 411 communicates with the pressure relief space 33, so that the overheated gas ejected from the first explosion-proof valve 411 can be directly ejected into the pressure relief space 33 through the first weak part 311.

[0080] The second partition 32 is arranged parallel to the bottom plate 12, and a plurality of second weak parts 321 are provided on the second partition 32. One second weak part 321 is arranged opposite to the second explosion-proof valve 511 of one second single cell 51. The second weak part 321 may be a through hole, so that the second explosion-proof valve 511 is not covered by the second partition 32, so that the second explosion-proof valve 511 communicates with the pressure relief space 33, so that the overheated gas ejected from the second explosion-proof valve 511 can be directly ejected into the pressure relief space 33 through the second weak part 321.

[0081] Certainly, in some other exemplary embodiments of the present disclosure, the first weak part 311 may also be a scratch or a groove provided on the first partition 31, and may also be a weak structure where the thickness at the first weak part 311 is thinner than that at other positions. The second weak part 321 may also be a scratch or a groove provided on the second partition 32, and may also be a weak structure where the thickness at the second weak part 321 is thinner than that at other positions.

[0082] Moreover, the second weak part 321 and the first weak part 311 may be arranged opposite to each other. Specifically, the orthographic projection of the second weak part 321 on the bottom plate coincides with the orthographic projection of the first weak part 311 on the bottom plate, so that the second explosion-proof valve 511 and the first explosion-proof valve 411 are arranged opposite to each other. Correspondingly, the orthographic projection of the second explosion-proof valve 511 on the bottom plate coincides with the orthographic projection of the first explosion-proof valve 411 on the bottom plate.

[0083] It should be noted that the coincidence not only includes complete coincidence, but may also have a certain error. According to different devices and manufacturing processes, the error range is also different. Therefore, within the error range of the device and the manufacturing process, it is considered to be coincident.

[0084] The first partition 31 can isolate the overheated gas ejected from the second explosion-proof valve 511 to prevent the overheated gas ejected from the second explosion-proof valve 511 from affecting the first single cell 41; similarly, the second partition 32 can isolate the overheated gas ejected from the first explosion-proof valve 411 to prevent the overheated gas ejected from the first explosion-proof valve 411 from affecting the second single cell 51, so that the two layers of single cells do not interfere with each other, basically achieving thermal isolation of the two layers of single cells, and improving the safety of the battery pack.

[0085] The "parallel" and "perpendicular" mentioned in this application can not only be completely parallel or perpendicular, but also can have a certain error; for example, if the angle between the two is greater than or equal to 0° and less than or equal to 5°, the two are considered to be parallel to each other; if the angle between the two is greater than or equal to 85° and less than or equal to 95°, the two are considered to be perpendicular to each other.

[0086] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the utility model disclosed herein. This application is intended to cover any variations, uses or adaptations of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A battery pack, characterized in that, Comprising: A battery box having a receiving cavity. The battery box includes a side frame. The side frame has an inner cavity. A first through hole and a second through hole are provided on the frame wall of the side frame close to the receiving cavity. The first through hole and the second through hole communicate with the inner cavity. A pressure relief structure is provided on the side frame. The inner cavity communicates with the pressure relief structure. The first through hole is disposed opposite to the pressure relief structure. An isolation structure is provided in the receiving cavity. The isolation structure divides the receiving cavity into a first receiving space and a second receiving space. The isolation structure includes a first partition and a second partition which are spaced apart and disposed opposite to each other. A pressure relief space is formed between the second partition and the first partition. The pressure relief space communicates with the inner cavity through the first through hole and the second through hole. A first battery pack is provided in the first receiving space. The first battery pack includes a first single battery. A second battery pack is provided in the second receiving space. The second battery pack includes a second single battery. A second explosion-proof valve of the second single battery is disposed opposite to a first explosion-proof valve of the first single battery and communicates with the pressure relief space.

2. The battery pack according to claim 1, characterized in that, The first through hole is located within the orthographic projection of the pressure relief space on the side frame. The orthographic projection of the pressure relief structure on the frame wall of the side frame close to the receiving cavity is disposed directly opposite to the first through hole.

3. The battery pack according to claim 1, wherein The second through hole is provided in plurality. The total opening area of the plurality of second through holes is greater than the opening area of the first through hole.

4. The battery pack according to claim 1, characterized in that, In a first direction, the distance between two adjacent second through holes is greater than or equal to 50 mm and less than or equal to 300 mm. The distance between the second through hole and the first through hole is greater than or equal to 25 mm and less than or equal to 150 mm. The first direction is parallel to the bottom plate of the battery box.

5. The battery pack according to claim 1, characterized in that The plurality of second through holes are arranged in a row in the first direction. At least two rows of the second through holes are arranged in a third direction. The first direction is parallel to the bottom plate of the battery box. The third direction is perpendicular to the bottom plate of the battery box.

6. The battery pack according to claim 5, characterized in that, The second through holes in two adjacent rows are disposed opposite to each other, or the second through holes in two adjacent rows are offset.

7. The battery pack according to claim 5, characterized in that, The second through hole is located within the orthographic projection of the pressure relief space on the side frame. In the third direction, the distance between two adjacent rows of the second through holes is greater than 0 and less than or equal to 15 mm.

8. The battery pack according to any one of claims 1 to 7, characterized in that, The pressure relief structure is fixed to the frame wall of the side frame facing away from the receiving cavity. A third through hole is provided on the frame wall of the side frame facing away from the receiving cavity. At least a part of the pressure relief structure is disposed opposite to the third through hole. The ratio of the opening area of the third through hole to the opening area of the first through hole is greater than or equal to 0.5 and less than 1.

9. The battery pack according to any one of claims 1 to 7, characterized in that, A first weak part is provided on the first partition. The first weak part is disposed opposite to the first explosion-proof valve. A second weak part is provided on the second partition. The second weak part is disposed opposite to the second explosion-proof valve.

10. The battery pack according to claim 9, characterized in that, The orthographic projection of the first weak part on the bottom plate of the battery box coincides with the orthographic projection of the second weak part on the bottom plate of the battery box, and the orthographic projection of the first explosion-proof valve on the bottom plate of the battery box coincides with the orthographic projection of the second explosion-proof valve on the bottom plate of the battery box.

Images