Battery pack and energy storage system

Abstract

The utility model provides a battery pack and energy storage system.The battery pack comprises a lower shell and a battery module arranged in a placing groove of the lower shell, the battery module comprises a plurality of battery cells, a battery cell explosion-proof valve of each battery cell is arranged downwards, the lower shell comprises a frame with a battery pack explosion-proof valve and a bottom plate arranged at the bottom of the frame, and the battery pack explosion-proof valve is arranged on the bottom plate. The placing groove is formed in an area defined by the frame and the top plate, a cavity is formed between the bottom plate and the top plate, the battery pack anti-explosion valves are located above the top plate and connected with the cavity through communicating pipelines, and avoiding holes corresponding to the battery cell anti-explosion valves one to one are formed in the top plate; and each avoiding hole is connected with the cavity. According to the battery pack disclosed by the utility model, high-temperature gas and electrolyte can be prevented from entering the battery pack, and the risks of short circuit and fire are reduced, so that the safety of the battery pack is favorably improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, and in particular to a battery pack. At the same time, the utility model also relates to an energy storage system provided with the battery pack. Background Art

[0002] In recent years, the new energy industry has developed rapidly, and the design integration of battery packs has become increasingly higher. In order to reduce system costs and improve volume utilization, most manufacturers have continuously increased the capacity of batteries, resulting in a continuous increase in the specific energy of batteries, which in turn leads to an increase in the safety risks of battery packs. Among them, battery thermal runaway is the most common.

[0003] Currently, when a battery experiences thermal runaway, the erupted high-temperature gas and electrolyte will first be discharged into the battery pack and then discharged outside the pack through an explosion-proof valve. This can easily damage the insulation between electrical components in the pack, causing a short circuit in the electrical components and resulting in secondary thermal runaway. Moreover, the electrolyte is flammable and explosive. When a large amount of electrolyte accumulates in the battery pack, it has a high risk of explosion and fire when encountering sparks or open flames, which is not conducive to improving the safety of the battery pack. Utility Model Content

[0004] In view of this, the present invention aims to provide a battery pack to improve the safety of the battery pack.

[0005] In order to achieve the above-mentioned purpose, the technical solution of the utility model is achieved as follows:

[0006] A battery pack comprises a lower shell, and a battery module arranged in a placement groove of the lower shell; the battery module comprises a plurality of battery cells, and the battery cell explosion-proof valve of each battery cell is arranged downward;

[0007] The lower shell includes a frame with a battery pack explosion-proof valve, a bottom plate arranged at the bottom of the frame, and a top plate arranged in the frame and located above the bottom plate, the placement groove is formed in the area enclosed by the frame and the top plate; a cavity is formed between the bottom plate and the top plate, the battery pack explosion-proof valve is located above the top plate and is connected to the cavity through a connecting pipe, and avoidance holes are provided on the top plate corresponding to each of the battery cell explosion-proof valves, and each of the avoidance holes is connected to the cavity.

[0008] Furthermore, a through hole is opened on the top plate, one end of the communicating pipe is connected to the battery pack explosion-proof valve, and the other end of the communicating pipe is connected to the through hole.

[0009] Furthermore, the battery cells are stacked along the length direction of the lower shell; a plurality of transverse ribs are arranged at intervals along the length direction of the lower shell in the cavity, and each of the transverse ribs extends along the width direction of the lower shell, dividing the cavity into a plurality of sub-cavities that are interconnected.

[0010] Furthermore, each of the transverse ribs is provided with a connecting portion, and in the thickness direction of the transverse rib, each of the connecting portions passes through the corresponding transverse rib to connect the sub-cavities on both sides of the corresponding transverse rib.

[0011] Furthermore, each of the communication portions includes a plurality of communication units arranged at intervals along the width direction of the lower shell, and each of the communication units is arranged one-to-one on a side of each of the avoidance holes close to the through hole.

[0012] Furthermore, each of the connecting units includes two connecting holes arranged at intervals along the width direction of the lower shell; each of the connecting holes passes through the top plate and the corresponding transverse ribs in sequence from top to bottom, or each of the connecting holes passes through the corresponding transverse ribs in the thickness direction of the transverse ribs.

[0013] Furthermore, the battery module also includes a plurality of battery frames arranged in sequence along the width direction of the lower shell, a plurality of battery cells are stacked in each of the battery frames, and the battery frames are detachably connected to the top plate.

[0014] Furthermore, in the length direction of the lower shell, the avoidance holes and the transverse ribs are arranged in a staggered manner.

[0015] Furthermore, each of the battery cells is glued to the top plate.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] The battery pack described in the present invention, by providing the avoidance hole, the cavity and the connecting pipe, and arranging the battery cell explosion-proof valve downward, can discharge the emissions into the cavity through the battery cell explosion-proof valve when the battery cell thermal runaway occurs, and discharge them out of the pack through the connecting pipe and the battery pack explosion-proof valve, thereby achieving thermal and electrical separation, avoiding problems such as insulation failure and high-voltage arcing, thereby reducing the risk of short circuit and fire in the battery pack, and further helping to improve the safety of the battery pack.

[0018] Secondly, by providing a through-hole in the top plate and connecting the connecting pipe between the battery pack explosion-proof valve and the through-hole, a discharge path for emissions is formed. Furthermore, the structure is simple and easy to design and implement. By providing transverse ribs and aligning the stacking direction of the battery cells perpendicular to the extension direction of the ribs, the structural strength of the device is enhanced. Furthermore, by interconnecting the multiple sub-cavities, the discharge of emissions is facilitated.

[0019] Furthermore, the connection section connects the sub-cavities on either side of the corresponding transverse ribs, allowing emissions to be collected at the through-holes and discharged through the battery pack explosion-proof valve, ensuring internal safety. The connection section, comprised of multiple connecting units, features a simple structure that is easy to design and implement. Each connecting unit corresponds to each avoidance hole, improving emission discharge efficiency. By having each connecting hole penetrate the transverse ribs, emissions can be precisely discharged, reducing the risk of internal short circuits in the battery pack.

[0020] Furthermore, multiple battery cells are stacked within corresponding battery frames, which are removably mounted on the top plate, facilitating assembly and disassembly, thereby improving production efficiency. The staggered arrangement of the relief holes and transverse ribs creates a rational structure, creating an exhaust path that facilitates the discharge of emissions out of the package. Each battery cell is bonded to the top plate with adhesive, enhancing the connection strength and stability of the cells.

[0021] In addition, another object of the present invention is to provide an energy storage system, in which the battery pack as described above is provided.

[0022] The energy storage system described in the present invention and the above-mentioned battery pack have the same beneficial effects as traditional technologies, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 This is a schematic diagram of the overall structure of the battery pack according to the first embodiment of the present invention;

[0025] Figure 2 for Figure 1 A cross-sectional view of the structure shown along the AA line;

[0026] Figure 3 for Figure 2 A magnified view of the structure shown at B in the middle;

[0027] Figure 4 This is a schematic structural diagram of the battery module according to the first embodiment of the present invention;

[0028] Figure 5 This is a schematic structural diagram of the lower housing according to the first embodiment of the present invention;

[0029] Figure 6 for Figure 5 An enlarged view of the structure shown in C;

[0030] Figure 7 This is a partial structural diagram of the battery pack according to the first embodiment of the present invention;

[0031] Figure 8 for Figure 7 A magnified view of the structure shown in D.

[0032] Description of reference numerals:

[0033] 1. Lower housing; 11. Bottom plate; 12. Top plate; 121. Avoidance hole; 122. Through hole; 13. Cavity; 131. Sub-cavity; 14. Frame; 141. Battery pack explosion-proof valve; 15. Placement groove; 16. Connecting pipe; 17. Horizontal rib; 171. Connecting portion; 1711. Connecting unit; 17111. Connecting hole;

[0034] 2. Battery module; 21. Battery frame; 22. Battery cell; 221. Battery cell explosion-proof valve;

[0035] 31. Foam double-sided tape; 311. Opening hole; 32. Structural adhesive; 33. Thickness limit strip. DETAILED DESCRIPTION

[0036] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.

[0037] In the description of this utility model, it should be noted that if terms such as "upper," "lower," "inner," and "outer" appear to indicate orientation or positional relationships, these are based on the orientation or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, if terms such as "first" and "second" appear, they are used solely for descriptive purposes and should not be construed as indicating or implying relative importance.

[0038] Taking the battery pack described in this utility model as an example, the directional words used in the embodiment, such as "up, down, left, right, front, back" are based on Figure 1 It is defined based on the up-down direction (also called height direction, or overall Z direction), left-right direction (also called width direction, or overall Y direction), and front-back direction (also called length direction, or overall X direction) shown in .

[0039] Furthermore, in the description of this utility model, unless otherwise explicitly defined, the terms "mounted," "connected," "connection," and "connector" should be interpreted broadly. For example, they can refer to fixed, removable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on specific circumstances.

[0040] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0041] Example 1

[0042] The present embodiment relates to a battery pack, which can prevent high-temperature gas and electrolyte from entering the pack, reduce the risk of short circuit and fire, and thus help improve the safety of the battery pack.

[0043] In terms of overall structure, Figures 1 to 8 As shown in , the battery pack of this embodiment includes a lower shell 1 and a battery module 2 arranged in the placement groove 15 of the lower shell 1, and the battery module 2 includes a plurality of battery cells 22, and the battery cell explosion-proof valve 221 of each battery cell 22 is arranged downward.

[0044] Among them, such as Figure 1 and Figure 3 As shown in , the lower housing 1 includes a frame 14 having a battery pack explosion-proof valve 141, a bottom plate 11 disposed at the bottom of the frame 14, and a top plate 12 disposed within the frame 14 and located above the bottom plate 11. A placement slot 15 is formed within the area enclosed by the frame 14 and the top plate 12. A cavity 13 is formed between the bottom plate 11 and the top plate 12. The battery pack explosion-proof valve 141 is located above the top plate 12 and connected to the cavity 13 via a connecting pipe 16. Avoidance holes 121 are provided on the top plate 12, one corresponding to each battery cell explosion-proof valve 221. Each avoidance hole 121 is connected to the cavity 13.

[0045] At this time, as set above, by setting the avoidance hole 121, the cavity 13 and the connecting pipe 16, and setting the battery cell explosion-proof valve 221 downward, when the battery cell 22 thermally runs away, the emissions can be discharged into the cavity 13 through the battery cell explosion-proof valve 221, and discharged outside the pack through the connecting pipe 16 and the battery pack explosion-proof valve 141, which can achieve thermal and electrical separation, avoid problems such as insulation failure and high-voltage arcing, thereby reducing the risk of short circuit and fire in the battery pack, and thus helping to improve the safety of the battery pack.

[0046] It should be noted that the emissions in this embodiment are high-temperature gases, electrolytes, etc. When thermal runaway occurs in the battery pack, each battery cell 22 discharges the emissions into the cavity 13 through the battery cell explosion-proof valve 221 at the bottom and the corresponding avoidance hole 121, and discharges them outside the pack through the connecting pipe and the battery pack explosion-proof valve 141, thereby realizing directional discharge of emissions and ensuring the safety inside the battery pack.

[0047] Based on the above overall introduction, in this embodiment, as a preferred implementation form, combined with Figure 1 and Figure 2 As shown in FIG, a through hole 122 is formed in the top plate 12. One end of the communication pipe 16 is connected to the battery pack explosion-proof valve 141, and the other end of the communication pipe 16 is connected to the through hole 122. Here, by forming the through hole 122 in the top plate 12 and connecting the communication pipe 16 between the battery pack explosion-proof valve 141 and the through hole 122, a discharge path for the exhaust is formed, and the structure is simple, easy to design and implement.

[0048] It is understandable that both ends of the connecting pipe 16 can respectively seal the connection with the battery pack explosion-proof valve 141 and the through hole 122, providing good sealing to ensure that the emissions will not leak into the pack.

[0049] Furthermore, in this embodiment, as a preferred implementation form, Figure 1 and Figure 4 As shown in , the battery cells 22 are stacked along the length of the lower housing 1. Meanwhile, the cavity 13 is provided with a plurality of transverse ribs 17 spaced along the length of the lower housing 1. Each transverse rib 17 extends along the width of the lower housing 1, dividing the cavity 13 into a plurality of interconnected sub-cavities 131.

[0050] The advantage of this arrangement is that by providing the transverse ribs 17 and aligning the stacking direction of the cells 22 with the extending direction of the transverse ribs 17, there is no need to cut the ends of the transverse ribs 17, which helps to enhance the structural strength of the device. Furthermore, the multiple sub-cavities 131 are interconnected, facilitating the discharge of waste.

[0051] Moreover, considering the emission requirements of emissions, in this embodiment, as a preferred implementation form, each transverse rib 17 is provided with a connecting portion 171. In the thickness direction of the transverse rib 17, each connecting portion 171 passes through the corresponding transverse rib 17 to connect the sub-cavities 131 on both sides of the corresponding transverse rib 17.

[0052] It should be noted that the thickness direction of the transverse rib 17 in this embodiment is the length direction of the lower shell 1, that is, Figure 1Thus, by setting the connecting portion 171, it is possible to penetrate the sub-cavities 131 on both sides of the corresponding transverse rib 17, so that the discharge can be collected at the position of the through hole 122 and discharged outside the battery pack through the battery pack explosion-proof valve 141, thereby ensuring the safety of the battery pack.

[0053] At the same time, in this embodiment, as a preferred implementation form, refer to Figure 5 and Figure 6 As shown in , each communication portion 171 includes a plurality of communication units 1711 spaced apart along the width of the lower housing 1, and each communication unit 1711 is arranged one-to-one on the side of each avoidance hole 121 near the through hole 122. Here, the communication portion 171 is composed of multiple communication units 1711, which has a simple structure and is easy to design and implement. In addition, each communication unit 1711 corresponds one-to-one to each avoidance hole 121, which helps improve the discharge efficiency of the exhaust.

[0054] In the specific structure, each avoidance hole 121 is provided with a connecting unit 1711 on one side close to the through hole 122. After the battery cell explosion-proof valve 221 discharges the emissions, it can be discharged through the corresponding connecting unit 1711, reducing the time required for the emissions to be discharged, thereby improving the safety inside the battery pack.

[0055] Specifically, as a preferred embodiment, still refer to Figure 6 As shown in , each communication unit 1711 of this embodiment includes two communication holes 17111 arranged at intervals along the width direction of the lower shell 1, and each communication hole 17111 passes through the corresponding transverse rib 17 in the thickness direction of the transverse rib 17.

[0056] In the specific structure, to prevent the electrolyte from being blocked by the communication holes 17111, each communication hole 17111 penetrates the corresponding transverse rib 17 from top to bottom, and a communication hole 17111 is provided on both sides of each avoidance hole 121 in the width direction of the lower shell 1. The discharge of each battery cell 22 can be discharged into the corresponding sub-cavity 131 through the corresponding avoidance hole 121, and then discharged into the through hole 122 through the two communication holes 17111, and then discharged through the communication pipe 16 and the battery pack explosion-proof valve 141. It should be understood that it is also possible for each communication unit 1711 to include a single communication hole 17111, that is, a communication hole 17111 is provided on one side of the avoidance hole 121 in the width direction of the lower shell 1.

[0057] It should be noted that the connecting hole 17111 in this embodiment can be set to a circle. Of course, in addition to being set to a circle, it can also be set to other common shapes, such as a triangle or a rectangle.

[0058] At the same time, in this embodiment, as another preferred implementation form, each communication hole 17111 sequentially penetrates the top plate 12 and the corresponding transverse rib 17 from top to bottom. As a result, after the transverse rib 17 is welded between the top plate 12 and the bottom plate 11, each communication hole 17111 penetrates the top plate 12 and the corresponding transverse rib 17 from top to bottom, thereby facilitating improved production convenience. This application preferably adopts this method.

[0059] In addition, in this embodiment, as a preferred implementation form, Figure 4 As shown, the battery module 2 also includes multiple battery frames 21 arranged sequentially along the width direction of the lower housing 1. Each battery frame 21 has multiple battery cells 22 stacked therein, and the battery frames 21 are detachably connected to the top plate 12. Here, multiple battery cells 22 are stacked in corresponding battery frames 21, and the battery frames 21 are detachably mounted on the top plate 12, which facilitates the disassembly and assembly of the battery frames 21 and helps improve production efficiency.

[0060] In the specific structure, the battery frames 21 in this embodiment can be set to six. Of course, the specific number of battery frames 21 can also be designed and adjusted accordingly according to actual needs. At the same time, the number of battery cells 22 in each battery frame 21 can be designed and adjusted accordingly according to actual needs. For example, it can be set to twelve, twenty or more. In this embodiment, the number of battery cells 22 in each battery frame 21 is thirty-four.

[0061] It should be noted that each battery frame 21 can be connected to the top plate 12 by screw connection. Of course, other common connection methods can also be used, as long as it can ensure that each battery frame 21 can be easily assembled and disassembled.

[0062] In addition, in this embodiment, as a preferred implementation form, the avoidance holes 121 and the transverse ribs 17 are staggered in the longitudinal direction of the lower shell 1. Thus, the avoidance holes 121 and the transverse ribs 17 are staggered, which is structurally reasonable and facilitates the formation of an exhaust path, thereby facilitating the discharge of exhaust gases out of the package.

[0063] In the specific structure, six avoidance holes 121 are arranged at intervals along the width direction of the lower shell 1 on the side of each transverse rib 17 away from the through hole 122. It is worth mentioning that a transverse rib 17 is also provided at the through hole 122 of this embodiment, and the through hole 122 passes through the transverse rib 17 from top to bottom.

[0064] In addition, in this embodiment, as a preferred implementation form, Figure 7 As shown in , each battery cell 22 is glued to the top plate 12. Here, each battery cell 22 is glued to the top plate 12, which is beneficial to improving the connection strength of the battery cell 22, thereby improving the stability of the placement of the battery cell 22.

[0065] In specific structures, such as Figure 3 、 Figure 7 and Figure 8 As shown in the figure, each battery cell 22 and the top plate 12 can be connected by a foam double-sided tape 31 in the prior art. In specific implementation, a foam double-sided tape 31 extending along the length direction of the lower shell 1 is provided under each battery frame 21. After each battery frame 21 is filled with battery cells 22, the foam surface of the corresponding foam double-sided tape 31 is adhered to the bottom surface of each battery cell 22 and then adhered to the top plate 12 to form a fixation.

[0066] At the same time, each foam double-sided tape 31 is also provided with an opening 311 corresponding to each battery cell explosion-proof valve 221, forming a avoidance for the battery cell explosion-proof valve 221. In addition, the foam double-sided tape 31 can also cover its corresponding communication hole 17111 to achieve sealing of exhaust and liquid discharge.

[0067] In addition, structural adhesive 32 is applied to both sides of each double-sided foam tape 31 along the width of the lower housing 1. In practice, each structural adhesive 32 is applied along the length of the lower housing 1, thereby strengthening the structural strength of the top plate 12 and the connection between the top plate 12 and the frame 14. The structural adhesive 32 in this embodiment can be epoxy resin structural adhesive 32, acrylate structural adhesive 32, or the like, which are well known to those skilled in the art.

[0068] It is still worth mentioning that if the structural adhesive 32 is applied too thickly, the curing time will be prolonged and it may not even be completely cured, thereby affecting the durability of the material. If the structural adhesive 32 is applied too thinly, it cannot effectively improve the structural strength of the top plate 12, thereby affecting its service life and safety.

[0069] Therefore, a thickness limiting strip 33 extending along the length direction of the lower shell 1 is provided between each foam double-sided tape 31 and the structural adhesive 32 on both sides thereof to limit the thickness of the structural adhesive 32. At the same time, the thickness limiting strip 33 can also prevent the structural adhesive 32 from flowing around the avoidance hole 121 when applying the structural adhesive 32, thereby damaging the battery cell explosion-proof valve 221 and causing leakage of the battery cell 22.

[0070] When the battery pack of this embodiment is in use, after each battery frame 21 is fully stacked with battery cells 22, double-sided tape is adhered to the bottom of each battery cell 22, and then adhered to the top plate 12, and each battery frame 21 is screwed and fixed to the top plate 12, and avoidance holes 121 corresponding to each battery cell explosion-proof valve 221 are opened on the top plate 12.

[0071] Through the above design, when the battery cell 22 thermally runs away, the emissions can be discharged into the corresponding sub-cavity 131 through the battery cell explosion-proof valve 221 and the avoidance hole 121 at the bottom, and collected at the through-hole 122 through the connecting holes 17111 on the transverse ribs 17. Subsequently, the emissions are discharged out of the pack through the connecting pipe 16 and the battery pack explosion-proof valve 141, thereby reducing the risk of short circuit and fire in the battery pack, thereby improving the safety of the battery pack.

[0072] Example 2

[0073] This embodiment also relates to an energy storage system, in which the battery pack in the first embodiment is provided.

[0074] The energy storage system described in this embodiment, by providing the battery pack of Example 1, can prevent high-temperature gas and electrolyte from entering the pack, reduce the risks of short circuit arcing, fire and explosion caused by thermal runaway of the battery pack, and thus help improve the safety of the battery pack.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A battery pack, characterized in that: It includes a lower shell, and a battery module arranged in a placement groove of the lower shell; The battery module includes a plurality of battery cells, and the explosion-proof valve of each battery cell is arranged downward; The lower housing includes a frame having a battery pack explosion-proof valve, a bottom plate provided at the bottom of the frame, and a top plate provided in the frame and located above the bottom plate, wherein the placement groove is formed in an area enclosed by the frame and the top plate; A cavity is formed between the bottom plate and the top plate. The battery pack explosion-proof valve is located above the top plate and is connected to the cavity through a connecting pipe. Avoidance holes corresponding to each battery cell explosion-proof valve are provided on the top plate, and each avoidance hole is connected to the cavity.

2. The battery pack according to claim 1, wherein: A through hole is provided on the top plate, one end of the communicating pipe is connected to the battery pack explosion-proof valve, and the other end of the communicating pipe is connected to the through hole.

3. The battery pack according to claim 2, wherein: The battery cells are stacked along the length direction of the lower shell; The cavity is provided with a plurality of transverse ribs arranged at intervals along the length direction of the lower shell, and each of the transverse ribs extends along the width direction of the lower shell, dividing the cavity into a plurality of sub-cavities that are interconnected.

4. The battery pack according to claim 3, wherein: A connecting portion is provided on each of the transverse ribs. In the thickness direction of the transverse ribs, each connecting portion passes through the corresponding transverse rib to connect the sub-cavities on both sides of the corresponding transverse rib.

5. The battery pack according to claim 4, wherein: Each of the communication portions includes a plurality of communication units arranged at intervals along the width direction of the lower shell, and each of the communication units is arranged one by one on a side of each of the avoidance holes close to the through hole.

6. The battery pack according to claim 5, wherein: Each of the communication units includes two communication holes arranged at intervals along the width direction of the lower shell; Each of the communicating holes passes through the top plate and the corresponding transverse rib in sequence from top to bottom, or each of the communicating holes passes through the corresponding transverse rib in the thickness direction of the transverse rib.

7. The battery pack according to claim 1, wherein: The battery module further includes a plurality of battery frames sequentially arranged along the width direction of the lower shell, a plurality of battery cells are stacked in each of the battery frames, and the battery frames are detachably connected to the top plate.

8. The battery pack according to claim 5, wherein: In the length direction of the lower shell, the avoidance holes and the transverse ribs are arranged alternately.

9. The battery pack according to claim 8, wherein: Each of the battery cells is connected to the top plate by adhesive bonding.

10. An energy storage system, characterized in that: The energy storage system is provided with a battery pack according to any one of claims 1 to 9.

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