Battery pack

Abstract

To provide a battery pack with improved safety performance.SOLUTION: A battery pack includes a lower shell 1, a battery cell stack 2, a first foam adhesive agent, and a plurality of partition members 5. The battery cell stack is disposed in the lower shell and includes a plurality of stacked soft pack battery cells. A bottom part side of the battery cell stack is connected to and fixed to a bottom part plate of the lower shell. A first partial region between a tab side of the battery cell stack and the lower shell is formed as an adhesive filled region. A second partial region is formed as an exhaust region, and the first foam adhesive agent is filled in the adhesive filled region. The plurality of partition members are attached to the exhaust region along a stacking direction of the soft pack battery cells and correspond to the plurality of soft pack battery cells on a one-to-one basis. The partition members are adapted to melt during exhaust of the soft pack battery cells corresponding to the partition members so as to form the exhaust paths communicating with an exhaust part of the soft pack battery cells corresponding to the partition members.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to the technical field of power batteries, and more particularly to battery packs. [Background technology]

[0002] The battery cell stack in the battery pack is susceptible to collision with the lower shell due to vibration during installation, transportation, and use. Collisions are particularly likely to cause short circuits on the tab side of the battery cell stack, which is susceptible to vibration deformation. Excessive fixation makes it difficult for high-temperature gas to be released in a timely manner in the event of thermal runaway in the battery cell stack, resulting in poor safety performance. Summary of the Invention [Problem to be solved by the invention]

[0003] In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a battery pack to solve the problem that the prior art battery packs have poor safety performance. [Means for solving the problem]

[0004] To achieve the above and other related objectives, the present application provides: A lower shell; a battery cell stack including a plurality of stacked soft-pack battery cells, the battery cell stack being disposed within the lower shell, the bottom side of the battery cell stack being connected and fixed to a bottom plate of the lower shell, a first partial area between the tab side of the battery cell stack and the lower shell being formed as an adhesive filling area, and a second partial area between the tab side of the battery cell stack and the lower shell being formed as an exhaust area; a first foam adhesive filled in the adhesive filling region; a plurality of partition members attached to the exhaust region along the stacking direction of the soft-pack battery cells, corresponding one-to-one to the plurality of soft-pack battery cells, the partition members adapted to melt when the soft-pack battery cells corresponding to the partition members are vented so as to form exhaust paths communicating with the exhaust sections of the soft-pack battery cells corresponding to the partition members; A battery pack including:

[0005] Optionally, an exhaust hole is provided on the partition member, the exhaust hole facing the exhaust portion and adapted to communicate with the exhaust portion when the soft-pack battery cell is evacuated.

[0006] Optionally, the vent hole extends along the length of the soft-pack battery cell and penetrates an end wall of the partition member so that gas discharged by the vent can flow inside the partition member.

[0007] Optionally, the lower shell includes an end beam, an exhaust chamber defined within the end beam, an explosion-proof valve mounted on the end beam adapted to exhaust air from the exhaust chamber, a tab side of the battery cell stack including a first tab side facing the end beam, and the partition member located on the first tab side of the battery cell stack and adapted to melt when the soft-pack battery cells are evacuated to form the exhaust path communicating with the exhaust chamber.

[0008] Optionally, the number of the battery cell stacks is two, the lower shell further includes an intermediate beam located between the two battery cell stacks, the tab side of the battery cell stack further includes a second tab side facing the intermediate beam, and a second foam adhesive is filled between the second tab side of the battery cell stack and the intermediate beam.

[0009] Optionally, the battery may further include an upper cover, the upper cover being positioned on an upper side of the battery cell stack and covering the lower shell, the end beam including a plurality of interconnected shrouds for defining the exhaust chamber, the shroud including an inner plate tightly attached to the partition member, and a gap between the upper end of the inner plate and the upper cover to form a communication portion connecting the exhaust path and the exhaust chamber.

[0010] Optionally, in the length direction of the soft pack battery cell, one end of the partition member is connected and attached to the soft pack battery cell, and the other end of the partition member is tightly and interference fit with the end beam of the lower shell.

[0011] Optionally, a slot is provided at one end of the partition member facing the soft-pack battery cells, and the partition member is inserted into the exhaust portion through the slot.

[0012] Optionally, the partition member comprises a melamine foam member.

[0013] Optionally, the soft pack battery cell has an air bag at an end in the length direction, and the exhaust portion includes the air bag.

[0014] Optionally, the bottom side of the battery cell stack is directly bonded and fixed to the bottom plate of the lower shell via a thermally conductive structural adhesive.

[0015] Optionally, in the height direction of the soft-pack battery cell, the first foam adhesive is located below the partition member and covers the tab of the soft-pack battery cell. [Effects of the Invention]

[0016] As described above, the battery pack of the present invention has at least the following advantageous effects: The bottom side of the battery cell stack is connected and fixed to the lower shell, and a first foam adhesive and a partition member are filled between the tab side of the battery cell stack and the lower shell, improving the stability of the battery cell stack and helping to prevent collisions and short circuits during transportation and vibration shock. Based on this, when thermal runaway occurs in the corresponding soft-pack battery cell, the partition member melts to form an exhaust path corresponding to the battery cell experiencing thermal runaway, allowing high-temperature gas to be discharged through the exhaust path corresponding to the soft-pack battery cell experiencing thermal runaway. This not only helps to discharge high-temperature gas in a timely manner, but also prevents it from affecting other soft-pack battery cells and preventing short circuits, thereby further improving the safety performance of the battery pack. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a structural schematic diagram of an embodiment of a battery pack of the present invention. [Figure 2] FIG. 2 is a structural schematic diagram of the battery pack of FIG. 1 after the top cover has been removed. [Figure 3] FIG. 3 is a structural schematic diagram of the battery cell stack of FIG. 2. [Figure 4] 4 is a structural schematic diagram of the partition member of FIG. 3 as viewed from a first viewpoint. FIG. [Figure 5] 4 is a structural schematic diagram of the partition member of FIG. 3 as viewed from a second viewpoint. FIG. [Figure 6] FIG. 2 is a front view of the battery pack of FIG. [Figure 7] FIG. 7 is a cross-sectional view taken along line AA in FIG. 6. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, the present invention will be described with reference to specific embodiments. Those skilled in the art will easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0019] The structures, proportions, sizes, and other elements shown in the drawings in this specification are used solely to supplement the contents disclosed herein and facilitate the understanding and interpretation of those skilled in the art, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance, and any changes in structure, proportions, or size adjustments are within the scope of the technical content disclosed in this specification as long as they do not affect the effects or objectives achieved by the present invention. At the same time, terms such as "top," "bottom," "left," "right," "center," and "one" used in this specification are used solely for the convenience of explanation and are not intended to limit the scope of the present application. Changes or adjustments to their relative relationships are also considered to be within the scope of the present invention as long as they do not substantially change the technical content.

[0020] 1 to 3, 6, and 7, in some optional embodiments, the present invention provides a battery pack including a lower shell 1, a battery cell stack 2, a first foam adhesive 31, and a plurality of partition members 5. The battery pack may further include an upper cover 4 in addition to the above components. The battery cell stack 2 includes a plurality of stacked soft-pack battery cells 21. The battery cell stack 2 is disposed within the lower shell 1, and the bottom side of the battery cell stack 2 is connected and fixed to the bottom plate 11 of the lower shell 1. A first partial region between the tab side of the battery cell stack 2 and the lower shell 1 is formed as an adhesive-filled region, and a second partial region is formed as an exhaust region. The first foam adhesive 31 is filled in the adhesive-filled region. The plurality of partition members 5 are attached to the exhaust region along the stacking direction of the soft-pack battery cells 21 and correspond one-to-one to the plurality of soft-pack battery cells 21. The partition members 5 are adapted to melt when the partition members 5 and the corresponding soft-pack battery cells 21 are vented, so as to form an exhaust path that communicates with the exhaust portions of the partition members 5 and the corresponding soft-pack battery cells 21.

[0021] Optionally, the bottom side of the battery cell stack 2 is directly bonded and fixed to the bottom plate 11 of the lower shell 1 via a thermally conductive structural adhesive, which provides a stable and reliable connection and is simple and convenient to operate.

[0022] Optionally, the upper cover 4 is located on the upper side of the battery cell stack 2 and covers the lower shell 1. Alternatively, the upper cover 4 can cover the upper opening of the lower shell 1, thereby storing the battery cell stack 2 in a storage space defined by the cooperation of the upper cover 4 and the lower shell 1.

[0023] Optionally, in the height direction of the soft-pack battery cells 21, the first foaming adhesive 31 is located below the partition member 5 and covers the tabs of the soft-pack battery cells 21. The first foaming adhesive 31 completely covers the tabs of the soft-pack battery cells 21, preventing them from being exposed, protecting them, improving the overall structural strength and insulating effect, and helping to reduce the risk of tab short circuits and heat diffusion. The partition member 5 is located above the first foaming adhesive 31, or the partition member 5 is located above the tabs of the soft-pack battery cells 21.

[0024] Optionally, both ends of the soft-pack battery cell 21 in the length direction have a tab. One side of the tab of the soft-pack battery cell 21 is the same side as the tab side of the battery cell stack 2. Here, in the present invention, the length direction of the soft-pack battery cell 21 and the length direction of the battery cell stack 2 are the same, i.e., the X direction in the drawings. The thickness direction of the soft-pack battery cell 21, the stacking direction of multiple soft-pack battery cells 21 in the same battery cell stack 2, and the width direction of the battery cell stack 2 are the same, i.e., the Y direction in the drawings. The height direction of the soft-pack battery cell 21, the height direction of the tab of the soft-pack battery cell 21, the height direction of the tab side of the battery cell stack 2, the height direction of the battery cell stack 2, and the height direction of the lower shell 1 are the same, i.e., the Z direction in the drawings.

[0025] Optionally, the partition member 5 includes a melamine foam member, which melts only when a certain temperature is reached, blocking the high-temperature gas emitted from the adjacent soft-pack battery cells 21 and reducing the risk of thermal diffusion. In addition, the melamine foam member can be melted by the action of the high-temperature gas emitted from the corresponding soft-pack battery cell 21 to form an exhaust path, which helps to exhaust the high-temperature gas in a timely manner.

[0026] Optionally, the soft pack battery cell 21 has an air bag at one end of its length, and the vent includes the air bag. Additionally, the vent may be located near the tab of the soft pack battery cell.

[0027] In the battery pack of the above embodiment, the battery cell stack 2 is connected and fixed to the lower shell 1, which helps improve the mounting stability of the battery cell stack 2. In particular, the bottom side of the battery cell stack 2 is directly connected to the lower shell 1, and the first foam adhesive 31 and the partition member 5 are filled between the tab side of the battery cell stack 2 and the lower shell 1. This provides the battery cell stack 2 with excellent structural stability and helps prevent the tab side of the battery cell stack 2 from colliding and causing a short circuit during transportation or vibration. Furthermore, the partition member 5 melts when thermal runaway occurs in the corresponding soft-pack battery cell 21, forming an exhaust path for the soft-pack battery cell 21 experiencing thermal runaway. This allows high-temperature gas to be quickly exhausted from the exhaust port of the soft-pack battery cell 21, improving exhaust efficiency. When not melted, the partition member 5 acts to block high-temperature gas exhausted from other soft-pack battery cells 21 and protect the soft-pack battery cell 21. If a thermal runaway occurs in each soft-pack battery cell 21, the battery pack has an exhaust path that can independently exhaust the heat, which is advantageous in reducing the risk of heat diffusion and short-circuiting of the soft-pack battery cells 21, and helps improve the safety performance of the battery pack.

[0028] 2 to 5 and 7, in some optional embodiments, the partition member 5 is provided with an exhaust hole 51 that faces the exhaust section and is adapted to communicate with the exhaust section when the soft-pack battery cells 21 are vented.

[0029] Optionally, the exhaust holes 51 extend along the length of the soft-pack battery cells 21 and penetrate the end walls of the partition members 5 so that gas discharged by the exhaust can flow inside the partition members 5. The partition members 5 can melt quickly from the inside to the outside under the action of high-temperature gas, forming an exhaust path and helping to discharge the high-temperature gas in a timely manner. Specifically, gas discharged from a soft-pack battery cell 21 experiencing thermal runaway first flows into the corresponding partition member 5, melting it, thereby lowering the temperature of the gas discharged. Therefore, the cooled gas cannot continue to melt the remaining partition members 5, ensuring the stability of the other partition members 5.

[0030] In the battery pack of the above embodiment, when thermal runaway occurs in the soft-pack battery cell 21, the high-temperature gas inside the soft-pack battery cell 21 is discharged from the exhaust section of the soft-pack battery cell 21 and flows into the exhaust hole 51. When the high-temperature gas flows into the exhaust hole 51, heat rapidly accumulates inside the partition member 5, causing the temperature to rise and melting the partition member 5, which forms an exhaust path in a timely manner and helps ensure the exhaust effect.

[0031] 2, 3, 6, and 7, in some optional embodiments, the lower shell 1 includes an end beam 13. An exhaust chamber 132 is provided within the end beam 13, and an explosion-proof valve 6 adapted to exhaust from the exhaust chamber 132 is provided on the end beam 13. The explosion-proof valve 6 can open to discharge high-temperature exhaust gas in the event of thermal runaway. The tab side of the battery cell stack 2 has a first tab side facing the end beam 13. The partition member 5 is located on the first tab side of the battery cell stack 2 and is adapted to melt when the soft-pack battery cells 21 are evacuated to form an exhaust path communicating with the exhaust chamber 132.

[0032] Optionally, the number of battery cell stacks 2 is two, and the lower shell 1 further includes an intermediate beam 14 located between the two battery cell stacks 2. The tab side of the battery cell stack 2 further includes a second tab side facing the intermediate beam 14. A second foam adhesive 32 is filled between the second tab side of the battery cell stack 2 and the intermediate beam 14. Furthermore, the second foam adhesive 32 fills the area between the second tab side of the battery cell stack 2 and the intermediate beam 14. That is, the entire area between the second tab side of the battery cell stack 2 and the intermediate beam 14 is filled with the second foam adhesive 32, which not only improves structural stability and helps prevent high-temperature gas from escaping to the second tab side of the battery cell stack 2, but also allows the second foam adhesive 32 to separate the tabs of multiple soft-pack battery cells 21, which helps to diffuse heat and reduce the risk of short circuits occurring in the tabs.

[0033] Optionally, the end beam 13 includes a plurality of interconnected shrouds for defining an exhaust chamber 132. The shroud includes an inner plate 133 that is tightly attached to the partition member 5. A gap is formed between the upper end of the inner plate 133 and the top cover 4 to form a communication opening 131 that connects the exhaust path and the exhaust chamber 132. High-temperature gas discharged from the soft-pack battery cells 21 passes through the exhaust path, the communication opening 131, and the exhaust chamber 132 in that order, and is discharged through the explosion-proof valve 6. The shroud further includes an outer plate 134 that faces the inner plate 133. The explosion-proof valve 6 is attached to the outer plate 134, and the upper end of the outer plate 134 is hermetically fitted to the top cover 4.

[0034] Optionally, one end of the partition member 5 is connected to and bonded to the soft-pack battery cell 21 in the length direction, and the other end of the partition member 5 is tightly and interference-fitted to the end beam 13 of the lower shell 1. Here, both ends of the exhaust hole 51 face the exhaust portion of the soft-pack battery cell 21 and the inner plate 133, respectively, and the partition member 5 is tightly and interference-fitted to the wall surface of the inner plate 133, ensuring a tight seal and effectively preventing the uncontrolled diffusion of high-temperature gas. Furthermore, the end of the partition member 5 facing the soft-pack battery cell 21 is inserted into the soft-pack battery cell 21. Specifically, a slot 52 is formed on the end of the partition member 5 facing the soft-pack battery cell 21, and the partition member 5 is inserted into the exhaust portion of the soft-pack battery cell 21 through the slot 52, making connection and assembly simple and convenient.

[0035] Optionally, the lower shell 1 further includes edge beams 12. The number of the edge beams 13 and the number of the edge beams 12 are both two. The edge beams 13 and the edge beams 12 are alternately distributed and connected end to end to form a square frame. The bottoms of the edge beams 13 and the edge beams 12 are connected to the bottom plate 11 of the lower shell 1. The structure of the lower shell 1 is simple and stable, and can provide stable mounting support for the battery cell stack 2.

[0036] In the battery pack of the above embodiment, if thermal runaway occurs in a soft-pack battery cell 21, high-temperature gas is discharged from the exhaust port near the tab of the soft-pack battery cell 21 and flows into the exhaust hole 51 of the partition member 5. The partition member 5 melts under the action of the high-temperature gas inside, forming the space previously occupied by the partition member 5 as an exhaust path. The high-temperature gas passes through the exhaust path and the communication portion 131, then flows into the exhaust chamber 132, and is discharged from the exhaust chamber 132 through the explosion-proof valve 6. Smooth discharge of high-temperature gas is advantageous in reducing the risk of thermal diffusion and short circuits. Furthermore, when the corresponding soft-pack battery cell 21 is in a normal state, the partition member 5 protects the soft-pack battery cell 21 and blocks high-temperature gas. If thermal runaway occurs in the corresponding soft-pack battery cell 21, the partition member 5 melts to open up a space and form an exhaust path. The compact layout reduces space occupation and waste, reduces costs, and improves the energy density of the battery pack.

[0037] In the battery pack of the present invention, a first foam adhesive 31 and a partition member 5 are provided between the tab side of the battery cell stack 2 and the lower shell 1. The partition member 5 cooperates with the first foam adhesive 31 to improve the structural stability and impact resistance of the battery cell stack 2, and in particular, effectively protects the tab side of the battery cell stack 2 and reduces the risk of short circuits and thermal diffusion. The partition member 5 melts when thermal runaway occurs in the soft-pack battery cell 21, helping to smoothly release high-temperature gas. The unmelted partition member 5 prevents the disorderly diffusion of high-temperature gas and reduces the risk of thermal diffusion, thereby improving the safety performance of the battery pack.

[0038] In the description herein, the use of terms such as "this embodiment," "example," and "specific example" means that the specific feature, structure, material, or characteristic described in combination with the embodiment or example is included in at least one embodiment or example of the present invention. In the description herein, exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in any one or more embodiments or examples.

[0039] The above embodiments are intended solely to illustrate the principles and effects of the present invention, and are not intended to limit the present invention. Those skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those with ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention should still be encompassed by the claims of the present application. [Industrial Applicability]

[0040] SUMMARY OF THE INVENTION An object of the present invention is to provide a battery pack that overcomes the problem of poor safety performance of prior art battery packs. [Explanation of symbols]

[0041] Lower Shell 1 bottom plate 11 Edge Beam 12 End beam 13 Communication part 131 Exhaust chamber 132 Inner plate 133 Outer plate 134 Intermediate beam 14 Battery cell stack 2 Soft pack battery cell 21 First foam adhesive 31 Second foam adhesive 32 Top cover 4 Partition member 5 Exhaust hole 51 Slot 52 Explosion-proof valve 6

Claims

1. A lower shell; a battery cell stack including a plurality of stacked soft-pack battery cells, the battery cell stack being disposed within the lower shell, the bottom side of the battery cell stack being connected and fixed to a bottom plate of the lower shell, a first partial area between the tab side of the battery cell stack and the lower shell being formed as an adhesive filling area, and a second partial area between the tab side of the battery cell stack and the lower shell being formed as an exhaust area; a first foaming adhesive filled in the adhesive filling region; a plurality of partition members attached to the exhaust region along the stacking direction of the soft-pack battery cells, corresponding one-to-one to the plurality of soft-pack battery cells, the partition members adapted to melt when the soft-pack battery cells corresponding to the partition members are vented so as to form exhaust paths communicating with the exhaust sections of the soft-pack battery cells corresponding to the partition members; A battery pack comprising:

2. An exhaust hole is provided on the partition member, the exhaust hole faces the exhaust section, and is adapted to communicate with the exhaust section when the soft-pack battery cell is vented.

2. The battery pack according to claim 1, wherein:

3. the exhaust hole extends along the length of the soft-pack battery cell and penetrates the partition member so that gas discharged by the exhaust portion can flow inside the partition member; 3. The battery pack according to claim 2, wherein:

4. the lower shell includes an end beam, an exhaust chamber is provided within the end beam, an explosion-proof valve is mounted on the end beam and adapted to exhaust from the exhaust chamber, the tab side of the battery cell stack includes a first tab side facing the end beam, and the partition member is located on the first tab side of the battery cell stack and adapted to melt when the soft-pack battery cells are evacuated to form the exhaust path communicating with the exhaust chamber; 2. The battery pack according to claim 1, wherein:

5. the number of the battery cell stacks is two, the lower shell further includes an intermediate beam located between the two battery cell stacks, the tab side of the battery cell stack further includes a second tab side facing the intermediate beam, and a second foam adhesive is filled between the second tab side of the battery cell stack and the intermediate beam; 5. The battery pack according to claim 4.

6. the battery cell stack further includes an upper cover, the upper cover being positioned on an upper side of the battery cell stack and covering the lower shell, the end beam including a plurality of shrouds connected to each other to define the exhaust chamber, the shroud including an inner plate in close contact with the partition member, and a gap between an upper end of the inner plate and the upper cover to form a communication portion that connects the exhaust path and the exhaust chamber; 5. The battery pack according to claim 4.

7. In the length direction of the soft-pack battery cell, one end of the partition member is connected to and bonded to the soft-pack battery cell, and the other end of the partition member is tightly and interference-fitted to the end beam of the lower shell.

5. The battery pack according to claim 4.

8. a slot is provided at one end of the partition member facing the soft-pack battery cell, and the partition member is inserted into the exhaust section through the slot; 8. The battery pack according to claim 1, wherein the battery pack comprises:

9. The partition member includes a melamine foam member.

8. The battery pack according to claim 1, wherein the battery pack comprises:

10. The soft-pack battery cell has an air bag at an end in the length direction, and the exhaust section includes the air bag.

8. The battery pack according to claim 1, wherein the battery pack comprises:

11. the bottom side of the battery cell stack is directly bonded and fixed to the bottom plate of the lower shell via a thermally conductive structural adhesive; 8. The battery pack according to claim 1, wherein the battery pack comprises:

12. In the height direction of the soft-pack battery cell, the first foam adhesive is located below the partition member and covers the tabs of the soft-pack battery cell.

8. The battery pack according to claim 1, wherein the battery pack comprises:

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