Battery pack

Abstract

The invention describes a battery pack, the battery pack comprises a box body, and a separator and a fire-fighting device which are arranged in the box body, the box body comprises a top plate and a bottom plate which are oppositely arranged; one end of the isolation piece is connected to the top plate of the box body, and a gap is formed between the other end of the isolation piece and the bottom plate; the fire fighting device is connected to the top plate and located on one side of the isolation piece, and the fire fighting device can release a fire extinguishing agent so that the fire extinguishing agent can diffuse in the box body. The battery pack further comprises an anti-explosion valve, and the anti-explosion valve is connected to the top plate and located on the side, away from the fire fighting device, of the isolation piece. Therefore, the fire extinguishing agent can fully diffuse in the box body before reaching the anti-explosion valve, so that a better fire extinguishing effect is achieved. In addition, the arrangement of the separator can also prolong the time of discharging the fire extinguishing agent from the explosion-proof valve, and reduce the probability of reburning of the battery pack.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery pack. Background Art

[0002] As a vital core component of new energy equipment, the fire safety of batteries has attracted widespread attention. Battery systems may catch fire due to a variety of reasons during operation, which not only threatens personal safety, but also may cause property loss and environmental pollution. Therefore, how to fully extinguish the fire in the case of a battery fire has become an important issue in battery safety research. Summary of the invention

[0003] The present application provides a battery pack that can improve the problem of insufficient fire extinguishing when a battery catches fire.

[0004] The present application provides a battery pack, which includes: a box body and an isolating member and a fire-fighting device arranged inside the box body, the box body includes a top plate and a bottom plate arranged opposite to each other; one end of the isolating member is connected to the top plate of the box body, and the other end of the isolating member has a gap with the bottom plate; the fire-fighting device is connected to the top plate and is located on one side of the isolating member, and the fire-fighting device can release a fire-extinguishing agent to diffuse in the box body; the battery pack also includes an explosion-proof valve, which is connected to the top plate and is located on the side of the isolating member away from the fire-fighting device.

[0005] Optionally, along the height direction of the box body, two ends of the isolation member are respectively in contact with the inner wall of the box body.

[0006] Optionally, the battery pack further includes a plurality of battery modules, wherein the battery modules are disposed in the box, and the isolation member is located between two adjacent battery modules.

[0007] Optionally, the number of the battery modules located on both sides of the isolation member is equal.

[0008] Optionally, the battery module includes a bottom surface facing the bottom plate, and a gap is provided between the bottom surface and the bottom plate.

[0009] Optionally, one end of the isolating member facing the bottom plate is on the same plane as the bottom surface; or, the bottom surface is located between one end of the isolating member facing the bottom plate and the bottom plate.

[0010] Optionally, the isolating member is provided with a first notch, which is provided at one end of the isolating member facing the top plate and is used to avoid electronic components of the battery pack, and the edge of the first notch fits the outer contour of the avoided electronic components.

[0011] Optionally, the isolating member is provided with a second notch, and the second notch is used to avoid the protruding structure on the inner wall of the box body.

[0012] Optionally, the isolation member includes a side facing the fire-fighting device or the explosion-proof valve, a first space facing the fire-fighting device separated by the isolation member in the box, and a second space facing the explosion-proof valve; a total channel for the fire-extinguishing agent to flow from the first space to the second space is formed between the edge of the isolation member and the inner wall of the box, and the area of ​​the total channel located in the plane where the side is located is S1; the channel formed by the end surface of the isolation member facing the bottom plate and the inner wall of the box is the designed channel, and the area of ​​the designed channel located in the plane where the side is located is S2; wherein, S2 / S1≥80%.

[0013] Optionally, along the height direction of the box body, the isolation piece protrudes from the surface of the battery module, and the protruding height is between 8 mm and 22 mm.

[0014] Optionally, the isolating member is bonded to the inner wall of the box body; and / or the isolating member is in a plate-like structure, and the thickness of the isolating member is between 2 mm and 5 mm.

[0015] Optionally, the battery pack also includes a battery management unit assembly and a fuse; the battery management unit assembly and the fuse are both connected to the top plate, and the battery management unit assembly is located between the fire-fighting device and the fuse, and the fire-fighting device is used to release a fire extinguishing agent by sensing temperature changes.

[0016] Optionally, the battery pack is a sodium ion battery pack.

[0017] The battery pack involved in the present invention includes a box, multiple battery modules, a separator, a fire-fighting device and an explosion-proof valve. The battery model is arranged in the box, and one end of the separator has a gap with the bottom plate. Through the gap, the fire-fighting device can release the fire-extinguishing agent to diffuse in the box. Among them, when a fire breaks out inside the battery pack, the fire-extinguishing agent will release the fire-extinguishing agent, and the explosion-proof valve will open to discharge the fire-extinguishing agent and smoke due to the increase in the internal pressure of the battery pack. Due to the setting of the separator, the fire-extinguishing agent will first diffuse in the side of the box corresponding to the fire-fighting device, and then diffuse through the gap to the side of the box corresponding to the explosion-proof valve. As a result, the fire-extinguishing agent can fully diffuse in the box before reaching the explosion-proof valve, so that the fire-extinguishing agent can reach various parts and areas of multiple battery modules as much as possible, and achieve more comprehensive coverage of multiple battery modules to achieve better fire-extinguishing effect. In addition, the setting of the separator can also prolong the time for the fire-extinguishing agent to be discharged from the explosion-proof valve, so that the fire-extinguishing agent can fully extinguish the flame in the battery pack and reduce the probability of re-ignition of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0019] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0020] Figure 1 It is a schematic diagram showing the overall structure of the battery pack involved in the present application.

[0021] Figure 2 It is a schematic diagram showing the partial structure of the battery pack involved in the present application.

[0022] Figure 3 It is a schematic diagram showing the release path of the fire extinguishing agent involved in the present application inside the battery pack.

[0023] Figure 4 is an exploded view showing the battery pack involved in the present application.

[0024] Figure 5 It is another partial structural schematic diagram showing the battery pack involved in the present application.

[0025] Figure 6 It is another partial structural schematic diagram showing the battery pack involved in the present application.

[0026] Figure 7 1 is a partial cross-sectional view showing the battery pack involved in the present application.

[0027] Figure 8 1 is a side view showing the battery pack involved in the present application.

[0028] Fig. 9 It is another partial structural schematic diagram showing the battery pack involved in the present application.

[0029] Fig.10 It is another partial structural schematic diagram showing the battery pack involved in the present application.

[0030] Fig.11 It is another partial structural schematic diagram showing the battery pack involved in the present application.

[0031] Figure numerals: 100, battery pack; 1, box body; 11, box cover; 111, top plate; 112, through groove; 113, through hole; 114, bottom plate; 12, base; 121, installation part; 13, maintenance cover; 14, insulating member; 15, crossbeam; 2, battery module; 21, first battery module; 22, second battery module; 23, third battery module; 24, fourth battery module; 3, isolating member; 31, first notch; 32, second notch; 4, fire-fighting device; 5, explosion-proof valve; 6, battery management unit assembly; 61, first bracket; 62, second bracket; 63, third bracket; 64, battery management unit; 65, weight reduction hole; 7, fuse; 8, high-voltage connector assembly; 9, liquid cooling pipe interface. DETAILED DESCRIPTION

[0032] Hereinafter, with reference to the accompanying drawings, the preferred embodiments of the present application are described in detail. In the following description, the same symbols are assigned to the same components, and repeated descriptions are omitted. In addition, the accompanying drawings are only schematic diagrams, and the ratio of the sizes of the components to each other or the shapes of the components may be different from the actual ones. It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0033] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time.

[0034] Reference Figures 1 to 4 The present application provides a battery pack 100, which includes a box body 1 and an isolating member 3 and a fire-fighting device 4 arranged inside the box body 1. The box body 1 includes a top plate 111 and a bottom plate 114 arranged opposite to each other; one end of the isolating member 3 is connected to the top plate 111 of the box body 1, and the other end of the isolating member 3 has a gap with the bottom plate 114; the fire-fighting device 4 is connected to the top plate 111 and is located on one side of the isolating member 3. The fire-fighting device 4 can release a fire-extinguishing agent to diffuse in the box body 1; the battery pack 100 also includes an explosion-proof valve 5, which is connected to the top plate 111 and is located on the side of the isolating member 3 away from the fire-fighting device 4.

[0035] According to the above structure, the battery model of the present application is arranged in the box body 1, and there is a gap between one end of the isolation member 3 and the bottom plate. Through the gap, the fire-fighting device 4 can release the fire-extinguishing agent to diffuse in the box body 1. Among them, when a fire occurs inside the battery pack 100, the fire-fighting device 4 will release the fire-extinguishing agent, and the explosion-proof valve 5 will open to discharge the fire-extinguishing agent and smoke due to the increase in the internal pressure of the battery pack 100. Due to the setting of the isolation member 3, the fire-extinguishing agent will first diffuse on the side of the box body 1 corresponding to the fire-fighting device 4, and then diffuse through the gap to the side of the box body 1 corresponding to the explosion-proof valve 5. As a result, the fire-extinguishing agent can fully diffuse inside the box body 1 before reaching the explosion-proof valve 5, so that the fire-extinguishing agent can reach various parts and areas of the multiple battery modules 2 as much as possible, and achieve more comprehensive coverage of the multiple battery modules 2 to achieve a better fire extinguishing effect. In addition, the provision of the isolation member 3 can also prolong the time for the fire extinguishing agent to be discharged from the explosion-proof valve 5, so that the fire extinguishing agent can fully extinguish the flame in the battery pack 100 and reduce the probability of the battery pack 100 re-igniting.

[0036] For easier understanding, please refer to Figure 1 The width direction of the box body 1 is the X-axis direction, the length direction of the box body 1 is the Y-axis direction, and the height direction of the box body 1 is the Z-axis direction. In this embodiment, the top plate 111 and the bottom plate 114 are distributed in the length direction of the box body 1.

[0037] Specifically, refer to Figure 3 Due to the setting of the isolation member 3, the path for the fire extinguishing agent to be discharged after being released can be a U-shaped structure, wherein the starting point of the U-shaped path is the fire-fighting device 4 and the end point is the explosion-proof valve 5. After the fire-fighting device 4 releases the fire-fighting agent, it is discharged from the fire-fighting device 4 and then diffuses in the direction of the bottom plate 114 at the fire-fighting device 4. In the early stage of the fire-fighting agent being released, the fire-fighting agent mainly stays on the side of the isolation member 3 facing the fire-fighting device 4. When the fire-fighting agent continues to diffuse, the fire-fighting agent will pass through the gap between the isolation member 3 and the bottom plate 114, and continue to diffuse to the side of the isolation member 3 facing the explosion-proof valve 5. Then, the fire-fighting agent continues to diffuse from the bottom plate 114 toward the explosion-proof valve 5, and is finally discharged from the explosion-proof valve to the outside of the box 1. In this way, the fire-fighting agent can be diffused in different areas on both sides of the isolation member in the box 1, and the residence time of the fire-fighting agent in the box 1 is prolonged. It is understandable that in the related art, since the isolation member 3 is not provided, the fire extinguishing agent is quickly discharged through the explosion-proof valve 5 before being fully diffused inside the battery pack 100 after being released, which may not only cause the fire extinguishing agent to fail to act near the battery module 2 where the fire started, but also may cause the fire extinguishing agent to be discharged too quickly, resulting in insufficient fire extinguishing, causing the fire in the battery module 2 to reignite. The battery pack 100 provided in the present application solves the above technical problems well.

[0038] The fire extinguishing agent selected in the present application can be a fire extinguishing aerosol, or a gaseous fire extinguishing agent that can be diffused, such as a carbon dioxide fire extinguishing agent or a nitrogen fire extinguishing agent. Specifically, after the fire-fighting device 4 is turned on, this type of fire extinguishing agent can diffuse in the space and cover the entire space to extinguish the fire, and this type of fire extinguishing agent will not have obvious residues after release, and will not damage the battery pack 100. Among them, the aerosol fire extinguishing agent is composed of an oxidant, a reductant and a combustion rate control agent, and is compressed into a solid block and installed in the fire-fighting device 4. After the fire-fighting device 4 is triggered, the aerosol fire extinguishing agent will quickly diffuse in the battery pack 100, and the battery module 2 in the battery pack 100 will be submerged in the aerosol smoke. After the aerosol fire extinguishing agent is released, it uses air as the dispersion medium and solid or liquid particles as the dispersed medium. It has gas fluidity and can diffuse around obstacles, thereby penetrating into corners and gaps to achieve comprehensive fire extinguishing coverage. In addition, the aerosol cloud formed during the release of the aerosol fire extinguishing agent can not only absorb the heat around the flame and reduce the temperature, but also compete with the oxygen in the flame and reduce the oxygen supply to the flame, thereby achieving the effect of suffocating the fire.

[0039] In some embodiments, along the height direction of the box body 1, the two ends of the isolating member 3 are respectively in contact with the inner wall of the box body 1. It is understandable that the upper and lower ends of the isolating member 3 can be as close to the inner wall of the box body 1 as possible, so that the fire extinguishing agent is difficult to pass through the upper and lower ends of the isolating member 3, so that the fire extinguishing agent can diffuse along the U-shaped path as much as possible. In this way, the fire extinguishing agent can reach various parts and areas of the multiple battery modules 2 as much as possible, achieve more comprehensive coverage of the multiple battery modules 2, and prolong the time for the fire extinguishing agent to be discharged from the explosion-proof valve 5.

[0040] In some embodiments, the battery pack 100 further includes a plurality of battery modules 2, and the separator 3 is located between two adjacent battery modules 2. Thus, battery modules 2 are provided on both sides of the separator 3, and under the action of the separator 3, the fire extinguishing agent can be fully diffused in the box 1, thereby achieving more comprehensive coverage of the battery modules 2 on both sides of the separator 3, so as to achieve a better fire extinguishing effect.

[0041] In some embodiments, the number of battery modules 2 on both sides of the separator 3 is equal. In this embodiment, it can also be understood that they are located in the middle of the top plate 111 along the width direction of the box body 1. Thus, the separator 3 evenly divides the space inside the box body 1, so that the space size on both sides of the separator 3 is nearly equal.

[0042] Reference Figure 5In some examples, along the width direction of the box body 1, the plurality of battery modules 2 include a first battery module 21, a second battery module 22, a third battery module 23 and a fourth battery module 24 arranged in sequence, and the isolation member 3 is located between the second battery module 22 and the third battery module 23. In other examples, one battery module 2 may be distributed on each side of the isolation member 3, or three battery modules 2 may be distributed on each side.

[0043] In some embodiments, the battery module 2 includes a bottom surface facing the bottom plate 114, and there is a gap between the bottom surface and the bottom plate 114. As a result, the fire extinguishing agent can diffuse into the gap between the bottom surface and the bottom plate 114, so that the fire extinguishing agent fully surrounds the battery module 2, and the fire extinguishing effect is better. It can be understood that a channel for the fire extinguishing agent to pass through can also be formed between the bottom surface and the bottom plate 114, and the channel can also allow the fire extinguishing agent to quickly pass from one side of the isolation member 3 to the other side.

[0044] In some embodiments, the end of the partition 3 facing the bottom plate 114 is on the same plane as the bottom surface. It is understandable that the bottom surface and the end of the partition 3 facing the bottom plate 114 are on the same plane, and a relatively complete channel can be formed between the bottom surface and the bottom plate, so that the fire extinguishing agent can quickly pass from one side of the partition 3 to the other side through the channel, and the fire extinguishing efficiency is higher. In other embodiments, the bottom surface is located between the end of the partition 3 facing the bottom plate 114 and the bottom plate 114. On the contrary, if the end of the partition 3 facing the bottom plate 114 protrudes from the bottom surface, the partition 3 intercepts part of the channel formed between the bottom surface and the bottom plate 114, which will affect the speed of the fire extinguishing agent diffusing to the other side of the partition 3 to a certain extent.

[0045] In some examples, in the height direction of the box 1, the bottom of the battery module 2 is connected to the bottom of the box 1, and there is a gap between the top of the battery module 2 and the box 1; along the lateral direction of the box 1, there is a gap between the outer wall of the battery module 2 and the inner wall of the box 1. Therefore, the setting of the gap can also make the fire extinguishing agent diffuse better in the box 1, so that the fire extinguishing agent can more fully cover the battery module 2, and the fire extinguishing effect is better.

[0046] In some embodiments, an insulating member 14 may be provided on the inner wall of the box body 1, and the insulating member 14 may be provided in an area other than the top plate 111. In the related art, since the battery pack 100 may be squeezed by external objects during use, if the box body 1 is squeezed and deformed, the inner wall of the box body 1 will directly contact the battery module 2. Therefore, the provision of the insulating member can provide a layer of insulating coverage, thereby enhancing the safety and reliability of the battery pack 100. Specifically, the insulating member 14 is a sheet-like structure and is attached to the inner wall of the box body 1. In some examples, the insulating member 14 and the spacer 3 can both be made of polypropylene material, which is referred to as PP and is a good electrical insulating material. The provision of the insulating member 14 can prevent contact between the battery module 2 and the box body 1, thereby avoiding the occurrence of short circuits.

[0047] Reference Figure 6 In some embodiments, the isolation member 3 is provided with a first notch 31, which is provided at one end of the isolation member 3 facing the top plate 111, for avoiding the electronic components of the battery pack 100, and the edge of the first notch 31 is in contact with the outer contour of the avoided electronic components.

[0048] The electronic device may be a battery management unit assembly 6 or a connecting copper busbar or other components, and these electronic devices are usually arranged in the area of ​​the top plate 111. Specifically, the shape of the first notch 31 can be designed according to the outer contour of the electronic device to be avoided, so that the edge of the first notch 31 can fit the outer contour of the electronic device as much as possible, so as to minimize the gap between the first notch 31 and the electronic device and reduce the fire extinguishing agent passing through the first notch 31.

[0049] In some embodiments, the isolating member 3 is provided with a second notch 32, and the second notch 32 is used to avoid the protruding structure of the inner wall of the box body 1. Since the inner wall of the box body 1 is usually not completely flat, such as Figure 4 In the embodiment, a raised crossbeam 15 is provided at the bottom of the box body 1, and the crossbeam 15 is used for connecting and fixing the battery module 2. The isolating member 3 needs to be provided with a second notch 32 for the crossbeam 15 to pass through, wherein the shape of the second notch 32 can be designed according to the outer contour of the crossbeam 15 to be avoided, so that the edge of the second notch 32 can fit the outer contour of the crossbeam 15 as much as possible, so as to minimize the gap between the second notch 32 and the crossbeam 15, and less fire extinguishing agent passes through the second notch 32.

[0050] Reference Figure 7In some embodiments, the isolator 3 includes a side facing the fire-fighting device 4 or the explosion-proof valve 5, a first space facing the fire-fighting device 4 separated by the isolator 3 in the box 1, and a second space facing the explosion-proof valve 5; a total channel for the fire-extinguishing agent to flow from the first space to the second space is formed between the edge of the isolator 3 and the inner wall of the box 1, and the area of ​​the total channel on the plane where the side is located is S1; the channel formed by the end surface of the isolator 3 facing the bottom plate and the inner wall of the box 1 is the designed channel, and the area of ​​the designed channel on the plane where the side is located is S2; wherein S2 / S1≥80%. Specifically, due to the existence of the first notch 31 and the second notch 32 and other structures in the isolator 3, and the inner wall of the box 1 is usually not completely flat. Therefore, the fire-extinguishing agent will also pass through the gap between the isolator 3 and the electronic device, and will also pass through the gap between the isolator 3 and the inner wall of the box 1. The above gap and the designed channel together form a total channel, except that the designed channel is used for the fire-extinguishing agent to pass through. It can be understood that S1=S2+the area of ​​the gap on the plane where the side is located. In order to ensure that the fire extinguishing agent passes through the designed channel as much as possible, S2 / S1 is set to be ≥ 80%, so that the proportion of the designed channel is as large as possible, and the fire extinguishing agent passes through the designed channel as much as possible, rather than through the gap, so that the fire extinguishing agent can be fully diffused inside the box 1 before reaching the explosion-proof valve 5, and reach various parts of the multiple battery modules 2 as much as possible, so as to achieve more comprehensive coverage of the multiple battery modules 2, so as to achieve a better fire extinguishing effect. And it can extend the time for the fire extinguishing agent to be discharged from the explosion-proof valve 5, so that the fire extinguishing agent can fully extinguish the flame in the battery pack 100, and reduce the probability of the battery pack 100 re-igniting.

[0051] The following describes, through comparative examples 1 to 2 and embodiments 1 to 5, the change in the fire extinguishing effect in the battery pack 100 according to the limitation of the ratio of S2 to S1 in the embodiments of the present application.

[0052] In the battery packs of Comparative Examples 1 to 2 and Examples 1 to 5, when a fire occurs in the battery pack 100, the following table records the proportion of flammable gas in the battery pack 100. See Table 1 for specific parameters.

[0053]

[0054] The technicians in this field can know from the above-mentioned comparative examples 1 to 2 and embodiments 1 to 5 that the provision of the isolation member 3 can improve the fire extinguishing effect, and when S2 / S1≥80%, the flammable gas in the battery pack 100 is lower and the fire extinguishing effect is better.

[0055] In some embodiments, the spacer 3 is bonded to the inner wall of the box body 1. Specifically, in the length direction of the box body 1, the end of the spacer 3 facing the top plate 111 is bonded to the top plate 111; in the height direction of the box body 1, the two ends of the spacer 3 are respectively bonded to the inner wall of the box body 1. Therefore, fixing the spacer 3 by bonding can have a more stable fixing effect and reduce the possibility of loosening and displacement. And bonding can provide a better sealing effect, because the adhesive can form a sealing layer after curing to prevent gas penetration. In addition, the adhesive can adapt to the uneven surface of the inner wall of the box body 1, and the connection effect is better.

[0056] In other embodiments, the spacer 3 may also abut against the inner wall of the box body 1. Specifically, since the spacer 3 is located between two adjacent battery modules 2, the spacer 3 may be sandwiched between the two adjacent battery modules 2, so that the spacer 3 can also be fixed in the box body 1. In the length direction of the box body 1, the end of the spacer 3 facing the top plate 111 can abut against the top plate 111, and in the height direction of the box body 1, the two ends of the spacer 3 can also abut against the inner wall of the box body 1.

[0057] In some examples, for ease of installation, the bottom end of the isolation member 3 is coated with glue in the height direction of the box body 1, and then inserted between two adjacent battery modules 2. The top of the isolation member 3 abuts against the inner wall of the box body 1, and the end of the isolation member 3 facing the top plate 111 can also abut against the top plate 111.

[0058] In some embodiments, along the height direction of the box body 1, the isolating member 3 protrudes from the surface of the battery module 2, and the protruding height is between 8mm-22mm. Among them, the distance that the isolating member 3 protrudes from the battery module 2 can also be the distance between the battery module 2 and the inner wall of the box body 1. The protruding height of 8mm-22mm can not only meet the requirements of the electrical design of the battery pack 100, but also make the structure of the battery pack 100 as compact as possible. In some examples, the height of the isolating member 3 protruding from the surface of the battery module 2 can be one of 8mm, 10mm, 13mm, 15mm, 18mm, 20mm, and 22mm.

[0059] In some embodiments, the isolator 3 is a plate-like structure, and the thickness of the isolator 3 is between 2mm and 5mm. In some examples, the thickness of the isolator 3 can be one of 2mm, 3mm, 3.5mm, 4mm, and 5mm. Among them, the selected isolator 3 can have a Shore hardness of 40HC-70HC, so that the isolator 3 can withstand a pressure below 10Kpa to ensure that the isolator 3 is not easily deformed due to excessive pressure when the battery pack 100 has thermal runaway, thereby causing the isolation function of the isolator 3 to fail. In addition, it will not be too thick and will not interfere with devices such as the battery module 2 inside the box 1.

[0060] In some embodiments, the battery pack 100 is a sodium ion battery pack 100. Therefore, the battery pack 100 of the present application uses sodium ions as charge carriers. Sodium is more abundant on earth than lithium, easier to obtain, has lower raw material costs, and lower production costs.

[0061] Reference Figure 2 In some embodiments, the battery pack 100 further includes a battery management unit assembly 6 and a fuse 7; the battery management unit assembly 6 and the fuse 7 are both connected to the top plate 111, and the battery management unit assembly 6 is located between the fire-fighting device 4 and the fuse 7, and the fire-fighting device 4 is used to release the fire-extinguishing agent by sensing the temperature change. Generally, the fuse 7 is the device with the highest operating temperature in the battery pack 100. Therefore, by arranging the battery management unit assembly 6 between the fire-fighting device 4 and the fuse 7, the fire-fighting device 4 is isolated from the fuse 7, thereby reducing the impact of the fuse 7 on the fire-fighting device 4 when it is heated, avoiding the fire-fighting device 4 from mistakenly releasing the fire-extinguishing agent, and ensuring the safety performance of the battery pack 100.

[0062] In the related art, the battery management unit component 6 in the battery is responsible for monitoring and managing the operating status of the battery, and can also perform operations such as balancing, such as adjusting the current to keep the power of all battery modules 2 consistent.

[0063] Among them, each battery module 2 is composed of multiple battery cells, and each battery cell is provided with an explosion-proof valve. When the battery pack 100 has thermal runaway, a large amount of heat is usually generated inside the battery cell. The hot air flow inside the battery cell can impact the explosion-proof valve, causing it to break or detach, so that the hot air flow can be discharged. In this embodiment, the fire-fighting device 4 will pull out a thermistor and arrange it near the explosion-proof valve of each battery cell. After thermal runaway occurs, the fire-fighting device 4 can sense the thermal runaway temperature. When the thermal runaway temperature reaches the preset value, it indicates that a fire has occurred in the battery pack 100, so as to trigger the fire-fighting device 4 to release the fire extinguishing agent to cool the inside of the battery pack 100 and isolate the oxygen.

[0064] Reference Figures 4 to 11In some embodiments, the battery management unit assembly 6 includes a first bracket 61, a second bracket 62 and two battery management units 64; the first bracket 61 is connected to the second bracket 62, and a receiving space is formed between the first bracket 61 and the second bracket 62, and the first bracket 61 and / or the second bracket 62 are connected to the top plate 111; one battery management unit 64 is connected to the side of the first bracket 61 away from the second bracket 62, and the other battery management unit 64 is connected to the second bracket 62 and is located in the receiving space. As a result, in the thickness direction of the battery management unit 64, the two battery management units 64 are overlapped and placed, and the structure of the battery management unit assembly 6 is more compact. In addition, compared with the battery pack 100 using one battery management unit 64 in the related art, the volume of one battery management unit 64 is usually larger, and the present embodiment can use two battery management units 64, and the single volume of the two battery management units 64 is smaller, so that the battery management unit 64 with a smaller volume can be flexibly installed on the battery pack 100, thereby improving space utilization.

[0065] Specifically, since the two battery management units 64 are respectively connected to the first bracket 61 and the second bracket 62, when a single battery management unit 64 needs to be maintained, it is only necessary to disassemble the corresponding bracket accordingly to perform the operation, which can significantly improve maintenance efficiency and reduce unnecessary disassembly work.

[0066] In some embodiments, the second bracket 62 includes a receiving groove that is recessed in a direction away from the first bracket 61, and the receiving groove forms a receiving space. Thus, the receiving groove of the second bracket 62 can accommodate a battery management unit 64. The first bracket 61 and the second bracket 62 are screwed together, and the second bracket 62 is screwed together with the top plate 111.

[0067] In other embodiments, the first bracket 61 includes a receiving groove that is recessed in a direction away from the second bracket 62 , and the receiving groove forms a receiving space.

[0068] Reference Fig.10 and Fig.11 The first bracket 61 and / or the second bracket 62 are provided with a weight-reducing hole 65. Therefore, the setting of the weight-reducing hole 65 not only helps to reduce the weight of the first bracket 61 and / or the second bracket 62, but also has a heat dissipation function. The weight-reducing hole 65 can facilitate air convection to dissipate the heat of the battery management unit 64, thereby keeping the temperature of the battery management unit 64 within a reasonable range.

[0069] In some embodiments, the battery management unit assembly 6 includes a third bracket 63 and two battery management units 64; the two battery management units 64 are respectively connected to opposite sides of the third bracket 63, and the third bracket 63 is connected to the box 1. Therefore, in this embodiment, the two battery management unit assemblies 6 are connected to the same third bracket 63, which reduces the use of brackets and reduces costs.

[0070] Reference Figure 4 In some embodiments, the box body 1 includes a box cover 11 and a base 12, and the bottom of the box cover 11 is detachably connected to the base 12; the top plate 111 is located on one side of the box cover 11, and the box cover 11 has an inner cavity for accommodating the battery module 2, and the battery module 2 is located in the inner cavity and connected to the base 12. Therefore, the bottom of the box cover 11 is detachably connected to the base 12, which can facilitate the inspection or maintenance of the inside of the box body 1 when necessary. Specifically, the box cover 11 and the base 12 can be screwed, and a sealing gasket can be provided between the box cover 11 and the base 12 to reduce the entry of moisture, dust and other pollutants into the connection gap between the box cover 11 and the base 12.

[0071] In the present application, the battery pack 100 can use a cold plate liquid cooling system to achieve heat transfer and temperature control. The cold plate is in contact with the battery module 2 and heat is transferred through the cold plate. When the heat of the battery module 2 is transferred to the cold plate, the coolant in the cold plate will absorb the heat and take it away through the circulation system.

[0072] In some embodiments, the battery pack 100 further includes a liquid cooling pipe interface 9, which is used to connect an external liquid cooling pipe, and the liquid cooling pipe interface 9 is connected to the cold plate. The base 12 includes a mounting portion 121, which protrudes from the side of the top plate 111 away from the battery module 2, and the liquid cooling pipe interface 9 is connected to the mounting portion 121. Therefore, the mounting portion 121 is protruding, which can facilitate the staff to connect the liquid cooling pipe interface 9 with the external liquid cooling pipe, providing more sufficient operating space.

[0073] In some embodiments, the battery pack 100 also includes a high-voltage connector assembly 8 and an explosion-proof valve 5; the fire-fighting device 4, the battery management unit assembly 6, the fuse 7 and the high-voltage connector assembly 8 are all connected to the outside of the top plate 111 and are located above the liquid cooling pipe interface 9. As a result, the fire-fighting device 4, the battery management unit assembly 6, the fuse 7 and the high-voltage connector assembly 8 can make full use of the space above the liquid cooling pipe interface 9, improve space utilization, and make the structure of the battery pack 100 more compact. Among them, the high-voltage connector assembly 8 of the battery pack 100 is responsible for connecting the battery module 2 with the external circuit to realize the transmission of electrical energy. Specifically, the high-voltage connector assembly 8 includes a high-voltage socket, which is connected to the high-voltage output end of the battery module 2 and is used to connect the circuit of the external electrical equipment. Refer to Figure 4The top plate 111 is provided with a through hole 113 through which a connecting line for connecting the high-voltage connector to the battery module 2 passes.

[0074] In some embodiments, the top plate 111 is provided with a through slot 112, which is connected to the interior of the box body 1; the box body 1 also includes a maintenance cover 13 detachably connected to the top plate 111, the maintenance cover 13 is provided with a storage space, the explosion-proof valve 5 is connected to the maintenance cover 13 and is connected to the storage space; the maintenance cover 13 covers the through slot 112, and the fire-fighting device 4, the battery management unit assembly 6, and the fuse 7 are located in the storage space. Since the fire-fighting device 4, the battery management unit assembly 6, and the fuse 7 usually need to be disassembled and operated only when they need to be replaced or maintained, and do not need to be connected to external electrical equipment like the high-voltage connector assembly 8. Therefore, the maintenance cover 13 is set to protect the fire-fighting device 4, the battery management unit assembly 6, and the fuse 7, and play a dustproof and waterproof function. Among them, the maintenance cover 13 can be screwed to the top plate 111, and when it is necessary to maintain or replace the internal components, the maintenance personnel can quickly disassemble and reinstall the maintenance cover 13 to improve the maintenance efficiency.

[0075] Reference Figure 8 In some embodiments, the distance that the maintenance cover 13 protrudes from the top plate 111 is between 15 mm and 25 mm.

[0076] In the interference test, it was found that when the distance that the maintenance cover 13 protrudes from the top plate 111 is defined as D, and 15mm≤D≤25mm, it can ensure that the maintenance cover 13 has enough accommodation space inside to accommodate the fire protection device 4, the battery management unit assembly 6, and the fuse 7, and the outside of the maintenance cover 13 will not interfere with the liquid cooling pipe interface 9, and can have enough assembly space. Therefore, the distance that the maintenance cover 13 protrudes from the top plate 111 is 15mm-25mm, which is the most ideal design for the compactness of the spacing structure and the rationality of the layout.

[0077] The following describes the design of the dimensional parameters according to the embodiments of the present application through comparative examples 3 to 4 and embodiments 6 to 10, wherein the following table records the design of the distance of the maintenance cover 13 protruding from the top plate 111 in each embodiment and comparative example, wherein in embodiments 6 to 10, when D is different values, the closest distance d1 between the maintenance cover 13 and the liquid cooling pipe interface 9, the distance d2 between the maintenance cover 13 and the liquid cooling pipe interface 9 in the length direction of the box 1, and the distance d3 between the maintenance cover 13 and the liquid cooling pipe interface 9 in the height direction of the box 1, and the interference between the maintenance cover 13 and each component is checked respectively. Specific parameters are shown in Table 2.

[0078]

[0079] In Example 9, referring to Figure 8, the distance D of the maintenance cover 13 protruding from the top plate 111 is 22mm. At this time, the closest distance d1 between the maintenance cover 13 and the liquid cooling pipe interface 9 is 9, the distance d2 between the maintenance cover 13 and the liquid cooling pipe interface 9 in the length direction of the box body 1 is -2.7, and the distance d3 between the maintenance cover 13 and the liquid cooling pipe interface 9 in the height direction of the box body 1 is 2.5. Among them, the negative value d2 can be understood as that in the length direction of the box body 1, the positions of the maintenance cover 13 and the liquid cooling pipe interface 9 partially overlap, but due to the setting of the distance d1 and the distance d2, there can be enough space between the maintenance cover 13 and the liquid cooling pipe interface 9, so the two will not interfere with each other.

[0080] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0081] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0082] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0083] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

[0084] Although the present application is specifically described above in conjunction with the accompanying drawings and embodiments, it is to be understood that the above description does not limit the present application in any form. Those skilled in the art may modify and change the present application as needed without departing from the essential spirit and scope of the present application, and these modifications and changes all fall within the scope of the present application.

Claims

1. A battery pack (100), characterized in that: include: A box body (1) and an isolating member (3) and a fire-fighting device (4) arranged inside the box body (1), wherein the box body (1) comprises a top plate (111) and a bottom plate (114) arranged opposite to each other; One end of the isolation member (3) is connected to the top plate (111) of the box body (1), and the other end of the isolation member (3) has a gap with the bottom plate (114); The fire-fighting device (4) is connected to the top plate (111) and is located on one side of the isolation member (3); the fire-fighting device (4) is capable of releasing a fire-extinguishing agent to diffuse into the box (1); The battery pack (100) further comprises an explosion-proof valve (5), wherein the explosion-proof valve (5) is connected to the top plate (111) and is located on a side of the isolation member (3) facing away from the fire-fighting device (4).

2. The battery pack (100) according to claim 1, characterized in that: Along the height direction of the box body (1), two ends of the isolation member (3) respectively abut against the inner wall of the box body (1).

3. The battery pack (100) according to claim 1, characterized in that: The battery pack (100) further comprises a plurality of battery modules (2), wherein the battery modules (2) are arranged in the box body (1), and the isolation member (3) is located between two adjacent battery modules (2).

4. The battery pack (100) according to claim 3, characterized in that: The number of the battery modules (2) located on both sides of the isolation member (3) is equal.

5. The battery pack (100) according to claim 3, characterized in that: The battery module (2) comprises a bottom surface facing the bottom plate (114), and a gap is formed between the bottom surface and the bottom plate (114).

6. The battery pack (100) according to claim 5, characterized in that: One end of the isolation member (3) facing the bottom plate (114) is on the same plane as the bottom surface; or, The bottom surface is located between one end of the isolation member (3) facing the bottom plate (114) and the bottom plate (114).

7. The battery pack (100) according to any one of claims 1 to 6, characterized in that: The isolating member (3) is provided with a first notch (31), and the first notch (31) is provided at one end of the isolating member (3) facing the top plate (111) and is used to avoid electronic components of the battery pack (100), and the edge of the first notch (31) is in contact with the outer contour of the electronic components to be avoided.

8. The battery pack (100) according to any one of claims 1 to 6, characterized in that: The isolating member (3) is provided with a second notch (32), and the second notch (32) is used to avoid the protruding structure on the inner wall of the box body (1).

9. The battery pack (100) according to any one of claims 1 to 6, characterized in that: The isolation member (3) comprises a side facing the fire-fighting device (4) or the explosion-proof valve (5), a first space facing the fire-fighting device (4) and a second space facing the explosion-proof valve (5) separated by the isolation member (3) in the box body (1); A general passage for the fire extinguishing agent to flow from the first space to the second space is formed between the edge of the isolation member (3) and the inner wall of the box body (1), and the area of ​​the general passage located on the plane where the side surface is located is S1; The channel formed by the end surface of the isolation member (3) facing the bottom plate (114) and the inner wall of the box body (1) is a designed channel, and the area of ​​the designed channel located on the plane where the side surface is located is S2; Among them, S2 / S1≥80%.

10. The battery pack (100) according to any one of claims 1 to 6, characterized in that: Along the height direction of the box body (1), the isolation member (3) protrudes from the surface of the battery module (2), and the protruding height is between 8 mm and 22 mm.

11. The battery pack (100) according to any one of claims 1 to 6, characterized in that: The isolation member (3) is bonded to the inner wall of the box body (1); and / or, The isolating member (3) is in a plate-like structure, and the thickness of the isolating member (3) is between 2 mm and 5 mm.

12. The battery pack (100) according to any one of claims 1 to 6, characterized in that: The battery pack (100) further comprises a battery management unit (64) component (6) and a fuse (7); The battery management unit (64) component (6) and the fuse (7) are both connected to the top plate (111), and the battery management unit (64) component (6) is located between the fire-fighting device (4) and the fuse (7), and the fire-fighting device (4) is used to release a fire-extinguishing agent by sensing temperature changes.

13. The battery pack (100) according to any one of claims 1 to 6, characterized in that: The battery pack (100) is a sodium ion battery pack (100).

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