Battery pack and electric device

Abstract

The application belongs to the field of batteries, and specifically provides a battery pack and an electric device. The battery pack comprises at least a battery group, a heat exchange plate and a box body. The battery group comprises a plurality of battery bodies arranged in an array, and the bottom surface of each battery body is provided with an explosion-proof valve. The heat exchange plate is arranged at the bottom of the battery group and is configured to exchange heat with the battery bodies. The heat exchange plate is provided with a through hole corresponding to the position of the explosion-proof valve. The box body is provided with a bottom guard plate, and a flow space is formed between the bottom guard plate and the heat exchange plate. The bottom surface of the heat exchange plate is provided with a blocking piece, the blocking piece is arranged at the position of the through hole of the heat exchange plate, and the blocking piece has a flow guide cavity in communication with the through hole. The opening of the flow guide cavity is in communication with the flow guide cavity and the flow space, so that the fluid sprayed by the explosion-proof valve is introduced into the flow space through the opening. The blocking piece and the bottom guard plate are provided with an adhesive layer, and the adhesive layer allows the blocking piece and the bottom guard plate to be separated from each other in the case that the battery body is heated to open the explosion-proof valve.

Description

Technical Field

[0001] This application relates to the field of batteries, specifically to a battery pack and an electrical device. Background Technology

[0002] In existing battery packs, explosion-proof valves are placed at the bottom of the batteries to achieve thermal and electrical separation. When a battery cell experiences thermal runaway, causing the explosion-proof valve to rupture, the fluid ejected from the valve has a relatively high temperature and pressure. The bottom protective plate of the enclosure is easily deformed or even melted by the impact of the fluid ejected from the explosion-proof valve, resulting in a tear in the bottom protective plate of the enclosure. Utility Model Content

[0003] In view of this, the present application aims to provide a battery pack and electrical equipment to solve the technical problem that when a battery cell in an existing battery pack ruptures due to thermal runaway, the temperature and pressure of the fluid ejected from the explosion-proof valve are relatively high, and the bottom protective plate of the box is easily deformed or even melted by the impact of the fluid ejected from the explosion-proof valve, resulting in a break in the bottom protective plate of the box.

[0004] The first aspect of this application provides a battery pack, comprising: A battery pack, comprising a plurality of battery cells arranged in an array, wherein an explosion-proof valve is provided on the bottom surface of each battery cell; A heat exchange plate is disposed at the bottom of the battery pack and is configured to exchange heat with the battery body. The heat exchange plate is provided with a through-hole corresponding to the position of the explosion-proof valve. The housing is provided with a bottom protective plate, and a flow space is formed between the bottom protective plate and the heat exchange plate; The heat exchange plate has a baffle on its bottom surface. The baffle is located at the through-hole of the heat exchange plate and has a flow guide cavity that communicates with the through-hole. The opening of the flow guide cavity connects the flow guide cavity and the flow space so that the fluid ejected by the explosion-proof valve is guided into the flow space through the opening. The partition and the bottom protective plate are provided with an adhesive layer, which allows the partition and the bottom protective plate to separate when the battery body is heated and the explosion-proof valve is opened.

[0005] Another aspect of this application provides an electrical device including the aforementioned battery pack.

[0006] In the battery pack of this application embodiment, the adhesive layer between the partition and the bottom cover plate can separate the partition and the bottom cover plate when the battery body is heated and the explosion-proof valve is opened. This increases the deformability range of the bottom cover plate when the explosion-proof valve is open, preventing the bottom cover plate of the box from deforming or even melting due to the impact of the fluid sprayed from the explosion-proof valve, which could lead to a break in the bottom cover plate of the box. This also prevents the fluid sprayed from the explosion-proof valve from breaking through the partition and the bottom cover plate of the box, thus preventing short circuits in the battery pack and its associated electrical equipment, and effectively improving the working safety of the battery pack and its associated electrical equipment. Attached Figure Description

[0007] It should be understood that the following figures only show some embodiments of this application and should not be regarded as a limitation on the scope.

[0008] It should be understood that the same or similar reference numerals are used in the accompanying drawings to denote the same or similar elements.

[0009] It should be understood that the accompanying drawings are only schematic, and the dimensions and scales of the elements in the drawings are not necessarily precise.

[0010] Figure 1 This is a perspective view of the battery pack according to an embodiment of this application.

[0011] Figure 2 This is a cross-sectional schematic diagram of the battery pack according to an embodiment of this application.

[0012] Figure 3 This is another cross-sectional schematic diagram of the battery pack according to an embodiment of this application.

[0013] Figure 4 This is another cross-sectional schematic diagram of the battery pack according to an embodiment of this application.

[0014] Figure 5 This is a partial perspective view of the battery pack according to an embodiment of this application.

[0015] Figure 6 This is another cross-sectional schematic diagram of the battery pack according to an embodiment of this application.

[0016] Attached image labels: 10. Enclosure; 11. Bottom panel; 12. Frame; 13. Main drain outlet; 20. Battery pack; 2. Battery body; 21. Housing; 22. Cover plate; 23. Explosion-proof valve; 29. ​​Battery row; 30. Heat exchange plate; 31. Baffle; 311. Intermediate partition; 312. End partition; 313. Lower partition; 314. Opening; 315. Adhesive layer; 316. Flow guide cavity; 32. Heat exchange channel; 40. Circulation space.

[0017] X - First direction; Y - Second direction; Z - Height direction. Detailed Implementation

[0018] Numerous specific details are set forth below to provide an understanding of the structure, function, and use of the embodiments described and illustrated in the specification and figures. It is to be understood that the embodiments described and illustrated herein are non-limiting examples, and thus it will be appreciated that the particular structural and functional details disclosed herein are representative and exemplary. Variations and changes may be made to these embodiments without departing from the scope of the claims.

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] like Figures 1 to 6 As shown in the figure, this application embodiment provides a battery pack, including a housing 10, a battery pack 20, and a heat exchange plate 30. The housing 10 includes a bottom protective plate 11 and a frame 12 fixed to the outer periphery of the bottom protective plate 11, with the bottom protective plate 11 and the frame 12 forming a receiving cavity. The receiving cavity is used to accommodate various structures required for the battery pack.

[0021] The battery pack of this embodiment comprises a battery pack 20, a battery management system, a thermal management system, an electrical connection system, structural components, and protective components, all housed within a housing 10 and sealed by a cover plate 22, forming a complete functional unit capable of directly outputting electrical energy. The battery pack 20 is formed by multiple battery cells 2 connected in series and / or parallel. The electrical connection system includes high-voltage connectors, low-voltage connectors, and wiring harnesses. The structural components include a housing and a support frame. This battery pack, as a rechargeable battery, can serve as a power source for new energy vehicles. The battery pack of this embodiment may also include an isolation plate. Both the battery cells 2 and the isolation plate are located within the housing 10. The isolation plate is located on the side of the battery cell 2 furthest from the bottom protective plate 11 of the housing 10, separating the battery cell 2 from other components located above it, thus providing isolation.

[0022] Specifically, the aforementioned enclosure 10 can be a closed or semi-closed structure made of materials such as metal or plastic. It serves as the physical carrier of the battery pack 20, and its design and manufacturing must meet the safety, reliability, and functionality requirements of the battery pack under different usage scenarios. The enclosure 10 provides installation space for the battery pack 20, BMS, cooling system, electrical connection components, etc., and through reasonable structural design, fixes these components inside the enclosure 10 to ensure that they maintain a relatively stable position during battery pack operation, avoiding damage to components or loosening of connections due to vibration, impact, or other factors.

[0023] The housing 10 may include a lower housing and an upper housing. The lower housing includes a bottom protective plate 11 and a frame 12 connected to and surrounding the bottom protective plate 11. The upper housing is connected to the frame 12 and has a cover plate 22 opposite to the bottom protective plate 11. The upper and lower housings together form a receiving cavity. The frame 12 and the bottom protective plate 11 can be integrally formed or processed separately and then fixedly connected. Specifically, the frame 12 and the bottom protective plate 11 are fixedly connected by welding, riveting, screwing, etc. When the housing 10 is a cube, the frame 12 of the lower housing generally has four side plates surrounding the periphery of the bottom protective plate 11. In other embodiments, the shape of the housing 10 may also be a cylinder or other shapes. The frame 12 mainly serves as support, protection, and connection. The frame 12 may be formed by splicing multiple beams together. The frame 12 may be rectangular, circular, polygonal, etc., and is not limited here. The beams of the frame 12 can be solid or contain cavities. The bottom protective plate 11 is the main load-bearing component of the battery pack, used to support and fix the battery pack 20, battery management system, cooling system and other components inside the battery pack. The housing 10 can be cast from materials such as steel and aluminum alloy, or lightweight materials such as glass fiber reinforced composite materials and carbon fiber reinforced composite materials.

[0024] like Figures 1 to 4 As shown, the battery pack 20 is disposed in the receiving cavity. The battery pack 20 includes a plurality of battery bodies 2 arranged in a row. An explosion-proof valve 23 is disposed on the bottom surface of the battery body 2.

[0025] It is understandable that multiple battery cells 2 with similar capacity and internal resistance are connected in series or parallel to form a battery pack 20. The battery cells 2 can store chemical energy and controllably convert it into electrical energy. In recyclable batteries, the active materials can be reactivated by charging after discharge for continued use. The battery cell 2 includes at least a housing 21 and a cover plate 22 fixedly connected to each other, as well as battery cells and electrolyte. The housing 21 and cover plate 22 together house the battery cells and electrolyte. The cover plate 22 may have at least one positive terminal and at least one negative terminal for electrical connection to the outside. When the housing 21 and cover plate 22 are welded together, the connection can be a weld seam left during welding; when the housing 21 and cover plate 22 are fixedly connected to each other by bonding, riveting, or other fixing methods, the connection can be a different structure. It is understandable that, compared to other locations on the side of the battery cell 2, the connection is generally more fragile and has lower structural strength. The battery cell includes one or more electrode assemblies. Each electrode assembly is formed by stacking or winding a positive electrode, a negative electrode, and a separator. The separator is located between adjacent positive and negative electrode sheets to insulate them. At least one end of each electrode assembly has a tab. One end of an adapter piece is electrically connected to the tab, and the other end is electrically connected to a terminal post. It is understood that the battery body 2 in this embodiment can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and is not limited thereto.

[0026] An explosion-proof valve 23 refers to a component or part that can be actuated to release internal pressure or temperature when the internal pressure or temperature of the battery body 2 reaches a predetermined threshold. During battery use, the explosion-proof valve 23 is mainly used to allow gas to escape from the battery and reduce internal pressure in the event of thermal runaway or other situations, preventing excessive pressure buildup that could cause deformation or explosion. The material of the explosion-proof valve 23 is not limited, including but not limited to aluminum, steel, alloys, etc. The shape of the explosion-proof valve 23 is not limited, such as square, oblong, elliptical, racetrack-shaped, etc. The type of explosion-proof valve 23 is not limited, such as a notched explosion-proof valve 23, which can be formed by stamping or laser etching.

[0027] Because an explosion-proof valve 23 is installed on the bottom surface of the battery body 2, when the internal pressure of the battery reaches the pressure relief strength of the explosion-proof valve 23, the explosion-proof valve 23 will connect with the outside and release pressure in time; the ejected material and other fluids from the explosion-proof valve 23 will be discharged downwards to avoid direct contact with the electrical components above the battery body 2, so as to achieve thermal and electrical separation and improve the overall safety of the battery pack.

[0028] The heat exchange plate 30 is disposed at the bottom of the battery pack 20 and is configured to exchange heat with the battery body 2; specifically, the heat exchange plate 30 is attached to the bottom surface of the battery body 2 and can heat and / or cool the battery body 2 as needed.

[0029] The heat exchange plate 30 is a component for regulating the temperature of the battery body 2. The heat exchange plate 30 has an internal heat exchange channel 32 for circulating a heat exchange medium. This medium can be a gas such as air, a liquid such as water, alcohol, refrigerant, or oil, or a solid such as thermally conductive adhesive or solder paste. The heat exchange channel 32 has an inlet and an outlet for the heat exchange medium. The medium enters the heat exchange channel 32 through the inlet, exchanges heat with the battery body 2, and then exits through the outlet, thus achieving heat exchange in the battery body 2. The heat exchange plate 30 can be made of a material with high thermal conductivity, such as copper; alternatively, a heat pipe can be installed inside the heat exchange plate 30, which can rapidly transfer heat through the principle of thermal convection; or, the heat exchange plate 30 can have a heat exchange channel 32 connected to a heating or cooling device, with a liquid medium flowing within it, enabling efficient heat exchange. The heat exchange plate 30 may include a heating element and an electrical connector. The heating element may be a heating wire, a heating film, or a heating plate; this application does not impose any limitations on this. The heat exchange plate 30 may be made of a metal material, such as aluminum alloy or magnesium alloy; it may also be made of plastic.

[0030] like Figure 2 As shown, the heat exchange plate 30 is provided with a through-hole corresponding to the position of the explosion-proof valve 23, and a flow space 40 is formed between the bottom protective plate 11 of the housing 10 and the heat exchange plate 30. In this way, because the heat exchange plate 30 is provided with a through-hole corresponding to the position of the explosion-proof valve 23, the ejected material and other fluids from the explosion-proof valve 23 can be discharged downward through the through-hole into the flow space 40 between the bottom protective plate 11 of the housing 10 and the heat exchange plate 30, and then discharged outside the battery pack.

[0031] Among them, such as Figures 2 to 5 As shown, a baffle 31 is provided on the bottom surface of the heat exchange plate 30. The baffle 31 is located at the through-hole of the heat exchange plate 30, and the baffle 31 has a flow guide cavity 316 communicating with the through-hole. The opening of the flow guide cavity 316 connects the flow guide cavity 316 and the flow space 40, so that the fluid ejected by the explosion-proof valve 23 is introduced into the flow space 40 through the opening. Therefore, during the operation of the battery pack in this embodiment, after the explosion-proof valve 23 of any battery body 2 ruptures, the ejected fluid, such as the ejected material, is discharged downward through the through-hole into the flow space 40 between the bottom guard plate 11 and the heat exchange plate 30 of the housing 10. Under the action of the baffle 31 located at the through-hole position on the bottom surface of the heat exchange plate 30, the fluid can flow in the direction of the opening of the guide cavity 316 within the guide cavity 316, thereby controlling the flow direction of at least a portion of the fluid ejected from the explosion-proof valve 23. By ensuring that the fluid ejected from the explosion-proof valve 23 does not flow through the area below other explosion-proof valves 23 on the path to the total outlet 13, it is possible to effectively prevent the fluid ejected from the explosion-proof valve 23 of any battery body 2 from flowing through the area below other explosion-proof valves 23 on the path to the total outlet 13. This prevents the high-temperature and high-pressure fluid from triggering a chain reaction of other explosion-proof valves 23 of the battery body 2, ensuring that other battery bodies 2 can still operate normally without being affected. It can effectively control the thermal runaway of the battery body 2, prevent the spread of thermal runaway, and effectively improve the working safety of the battery pack.

[0032] like Figures 2 to 6 As shown, the partition 31 and the bottom protective plate 11 are provided with an adhesive layer 315. When the battery body 2 is heated and the explosion-proof valve 23 is opened, the adhesive layer 315 allows the partition 31 and the bottom protective plate 11 to be separated from each other.

[0033] In the battery pack of this application embodiment, the adhesive layer 315 between the partition 31 and the bottom protective plate 11 can separate the partition 31 and the bottom protective plate 11 when the battery body 2 is heated and the explosion-proof valve 23 is opened. This increases the deformability range of the bottom protective plate 11 when the explosion-proof valve 23 is open, preventing the bottom protective plate 11 of the box 10 from being deformed or even melted by the impact of the fluid sprayed from the explosion-proof valve 23, which could cause a break in the bottom protective plate 11 of the box 10. This also prevents the fluid sprayed from the explosion-proof valve 23 from breaking through the partition 31 and the bottom protective plate 11 of the box 10, which could cause a short circuit in the battery pack and its associated electrical equipment, thus effectively improving the working safety of the battery pack and its associated electrical equipment.

[0034] Specifically, in one embodiment of this application, the adhesive layer 315 is configured to melt under the heating effect of the fluid ejected from the explosion-proof valve 23, and the melting point is t℃, where t℃ satisfies 100℃≤t℃≤300℃. That is, in the battery pack of this embodiment, after the fluid ejected from the explosion-proof valve 23 is ejected to the partition 31, it can heat the adhesive layer 315 through the partition 31, thereby causing the adhesive layer 315 to melt after reaching its melting point. It can be understood that when the adhesive layer 315 reaches its melting point and is in a molten state, the adhesive strength is basically 0, thereby allowing the partition 31 and the bottom protective plate 11 to separate from each other.

[0035] Since the melting point t℃ of the adhesive layer 315 satisfies 100℃≤t℃≤300℃, it can ensure that the adhesive layer 315 will not melt during the normal operation of the battery pack, thus ensuring the bonding strength between the partition 31 and the bottom protective plate 11. It can also melt quickly after the explosion-proof valve 23 sprays out fluid, thereby enabling the partition 31 and the bottom protective plate 11 to separate from each other as soon as possible, increasing the deformability range of the bottom protective plate 11, and preventing the fluid sprayed out by the explosion-proof valve 23 from breaking through the partition 31 and the bottom protective plate 11 of the box 10, which could lead to short circuits in the battery pack and its associated electrical equipment, thus effectively improving the working safety of the battery pack and its associated electrical equipment.

[0036] In one embodiment of this application, the adhesive strength of the adhesive layer 315 in the solid state is f MPa, where f MPa satisfies 1 MPa ≤ f MPa ≤ 10 MPa. Since the adhesive strength f MPa of the adhesive layer 315 in the solid state satisfies 1 MPa ≤ f MPa ≤ 10 MPa, the adhesive strength between the partition 31 and the bottom protective plate 11 is sufficient during normal operation of the battery pack. This allows them to remain relatively fixed, preventing collisions between the partition 31 and the bottom protective plate 11 of the heat exchange plate 30 when the battery pack is under vibration, thus improving the structural stability of the heat exchange plate 30 and the bottom protective plate 11.

[0037] like Figure 3 As shown, in one embodiment of this application, the thickness of the adhesive layer 315 is e mm, where e mm satisfies 0.5 mm ≤ e mm ≤ 3 mm.

[0038] When the thickness e mm of the adhesive layer 315 is less than 0.5 mm, the adhesive strength of the adhesive layer 315 is low, and the adhesive layer 315 cannot guarantee the adhesive strength between the partition 31 and the bottom protection plate 11, which can easily lead to separation between the partition 31 and the bottom protection plate 11 after the battery pack has been operating normally for a long time. When the thickness e mm of the adhesive layer 315 is greater than 3 mm, the melting speed of the adhesive layer 315 is slow after the explosion-proof valve 23 ruptures and sprays out fluid, which makes it impossible for the partition 31 and the bottom protection plate 11 to separate from each other as quickly as possible.

[0039] Therefore, when the thickness e mm of the adhesive layer 315 satisfies 0.5 mm ≤ e mm ≤ 3 mm, it can ensure that the partition 31 and the bottom protective plate 11 will not separate after the battery pack has been working normally for a long time. It can also ensure that the adhesive layer 315 reaches its melting point as soon as possible after the high temperature and high pressure fluid is sprayed out by the explosion-proof valve 23 of the battery body 2. This allows the partition 31 and the bottom protective plate 11 to separate from each other as soon as possible, increases the deformable range of the bottom protective plate 11, and prevents the fluid sprayed out by the explosion-proof valve 23 from breaking through the partition 31 and the bottom protective plate 11 of the box body 10.

[0040] In one embodiment of this application, the adhesive layer 315 is a structural adhesive; the adhesive layer 315 made of structural adhesive can bond the partition 31 and the bottom protective plate 11 together in a solid state, ensuring the bonding strength between the partition 31 and the bottom protective plate 11, and losing the bonding strength after reaching the melting point, so that the partition 31 and the bottom protective plate 11 can be separated from each other as soon as possible.

[0041] like Figure 5 As shown, in one embodiment of this application, the partition 31 includes a middle partition 311 and a lower partition 313. The middle partition 311 connects the heat exchange plate 30 and the lower partition 313. The projection of the explosion-proof valve 23 on the bottom protective plate 11 is located within the projection of the lower partition 313 on the bottom protective plate 11. The lower partition 313 is bonded and fixed to the bottom protective plate 11 of the housing 10 by an adhesive layer 315. The middle partition 311 can block the flow of fluid ejected from the explosion-proof valve 23, thereby blocking and guiding the fluid ejected from the explosion-proof valve 23. The fluid ejected from the explosion-proof valve 23 moves away from the middle partition 311, so that the flow process of the fluid ejected from the explosion-proof valve 23 avoids the area below other explosion-proof valves 23, preventing the high-temperature and high-pressure fluid from triggering a chain reaction of other battery body 2 explosion-proof valves 23 being ejected. The lower partition 313 can buffer the high-temperature and high-pressure fluid ejected by the explosion-proof valve 23, so that the fluid ejected by the explosion-proof valve 23 will not be directly ejected onto the bottom guard plate 11 of the box 10, thus avoiding the bottom guard plate 11 of the box 10 being directly impacted by the fluid ejected by the explosion-proof valve 23.

[0042] Specifically, such as Figure 6 As shown, in one embodiment of this application, the projected area of ​​the adhesive layer 315 on the bottom protective plate 11 is s(1) mm. 2 The projected area of ​​the lower partition 313 on the bottom protective plate 11 is s(2) mm. 2 , s(1) / s(2) satisfies 0.5≤s(1) / s(2)≤0.95.

[0043] The projected area s(1) mm of the adhesive layer 315 2 The projected area s(2) mm of the lower partition 313 2 When the ratio s(1) / s(2) is less than 0.5, the coverage area of ​​the adhesive layer 315 is low, and the adhesive layer 315 cannot guarantee the bonding strength between the partition 31 and the bottom protective plate 11. The projected area s(1) mm of the adhesive layer 315... 2 The projected area s(2) mm of the lower partition 313 2 When the ratio s(1) / s(2) is greater than 0.95, it is easy to waste the material cost of the adhesive layer 315.

[0044] Therefore, the projected area s(1) mm of the adhesive layer 315 2The projected area s(2) mm of the lower partition 313 2 When the ratio s(1) / s(2) satisfies 0.5≤s(1) / s(2)≤0.95, it can ensure that the bonding strength between the partition 31 and the bottom protective plate 11 will not separate after the battery pack has been working normally for a long time, and it can also effectively save the material cost required for the adhesive layer 315. In a specific embodiment, the projected area s(1) mm of the adhesive layer 315 is... 2 The projected area s(2) mm of the lower partition 313 2 The ratio s(1) / s(2) can be selected from specific values ​​such as 0.5, 0.6, 0.65, 0.8, 0.95, etc., without any restrictions here.

[0045] like Figure 6 As shown, in one embodiment of this application, the projected area s(1)mm of the adhesive layer 315 on the bottom protective plate 11 is... 2 Meets 400 mm 2 ≤s(1) mm 2 ≤1500 mm 2 .

[0046] The projected area s(1) mm of the adhesive layer 315 on the bottom protective plate 11 2 Less than 400 mm 2 In this case, the coverage area of ​​adhesive layer 315 is low, and adhesive layer 315 cannot guarantee the bonding strength between the partition 31 and the bottom protective plate 11. The projected area of ​​adhesive layer 315 on the bottom protective plate 11 is s(1) mm. 2 Greater than 1500 mm 2 In such cases, it is easy to waste the material cost of the adhesive layer 315.

[0047] Therefore, the projected area s(1) mm of the adhesive layer 315 2 Meets 400 mm 2 ≤s(1) mm 2 ≤1500 mm 2 In this way, the bonding strength between the partition 31 and the bottom cover plate 11 can be guaranteed, and the partition 31 and the bottom cover plate 11 will not separate after the battery pack has been working normally for a long time. At the same time, the material cost required for the adhesive layer 315 can be effectively saved.

[0048] In a specific embodiment, the projected area s(1) mm of the adhesive layer 315 2 500 mm can be selected 2 900 mm 2 1200mm 2 1400mm 21500 mm 2 Specific values ​​are not limited here.

[0049] like Figure 6 As shown, in one embodiment of this application, the projected area s(2)mm of the lower partition 313 on the bottom protective plate 11 is... 2 Meets 500 mm 2 ≤s(2) mm 2 ≤1600 mm 2 .

[0050] The projected area s(2) mm of the lower partition 313 2 Less than 500 mm 2 In this case, the coverage area of ​​the lower partition 313 is relatively small, and some of the fluid ejected from the explosion-proof valve 23 can easily spray out to areas outside the lower partition 313 on the bottom protective plate 11, causing some areas of the bottom protective plate 11 to be impacted by the fluid ejected from the explosion-proof valve 23, resulting in deformation and other issues. The projected area of ​​the lower partition 313 is s(2) mm. 2 Greater than 1600 mm 2 In this case, the overall area of ​​the lower partition 313 is relatively large, which increases the material cost required for the lower partition 313.

[0051] Therefore, the projected area s(2) mm of the lower partition 313 on the bottom guard plate 11 2 Meets 500 mm 2 ≤s(2) mm 2 ≤1600 mm 2 Under these conditions, it is possible to ensure that a portion of the fluid ejected from the pressure relief valve is ejected into the area within the reinforcing plate on the bottom guard plate, thus avoiding the impact of the fluid ejected from the pressure relief valve on the bottom guard plate area. This also effectively saves on the overall area of ​​the reinforcing plate, reducing the material cost required for the reinforcing plate.

[0052] In a specific embodiment, the projected area s(2) mm of the lower partition 313 on the bottom protective plate 11 2 500 mm can be selected 2 600 mm 2 1200mm 2 1400mm 2 1600 mm 2 Specific values ​​are not limited here.

[0053] like Figure 3As shown, in one embodiment of this application, the thickness of the adhesive layer 315 is e mm, where e mm satisfies 0.5 mm ≤ e mm ≤ 3 mm. When the thickness e mm of the adhesive layer 315 is less than 0.5 mm, the adhesive layer 315 cannot guarantee the bonding strength between the partition 31 and the bottom protective plate 11. When the thickness e mm of the adhesive layer 315 is greater than 3 mm, the temperature rise rate of the adhesive layer 315 is slow, making it difficult to quickly reach the melting point after the explosion-proof valve 23 ruptures, resulting in a longer separation time between the partition 31 and the battery pack bottom protective plate 11.

[0054] Therefore, when the thickness e mm of the adhesive layer 315 satisfies 0.5 mm ≤ e mm ≤ 3 mm, it can ensure the bonding strength between the partition 31 and the bottom protective plate 11, and also allow it to melt quickly after the explosion-proof valve 23 sprays fluid, thereby enabling the partition 31 and the bottom protective plate 11 to separate from each other as soon as possible and increasing the deformability range of the bottom protective plate 11. In specific embodiments, the thickness e mm of the adhesive layer 315 can be selected from specific values ​​such as 0.5 mm, 1 mm, 2 mm, 2.5 mm, and 3 mm, and is not limited here.

[0055] like Figure 3 As shown, in one embodiment of this application, the thickness of the lower partition 313 is d mm, where d mm satisfies 0.5 mm ≤ d mm ≤ 2 mm. When the thickness d mm of the lower partition 313 is less than 0.5 mm, the impact resistance of the lower partition 313 is poor, making it difficult to buffer the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23. This can easily lead to deformation or even melting of the lower partition 313 due to the impact of the fluid ejected from the explosion-proof valve 23. When the thickness d mm of the lower partition 313 is greater than 2 mm, the thickness of the lower partition 313 is too large. This not only occupies too much space below the explosion-proof valve 23, affecting the discharge efficiency of the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 to the total discharge port 13 of the housing 10, but also reduces the temperature transfer efficiency of the lower partition 313. This makes it difficult for the temperature of the adhesive layer 315 to rise to the melting point, making it difficult for the partition 31 and the bottom protective plate 11 of the battery pack to separate from each other.

[0056] Therefore, when the thickness d mm of the lower partition 313 satisfies 0.5 mm ≤ d mm ≤ 2 mm, not only can the impact resistance of the lower partition 313 be guaranteed, effectively buffering the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 and preventing deformation or even melting of the lower partition 313 due to the impact of the fluid ejected from the explosion-proof valve 23, but it can also prevent the lower partition 313 from affecting the discharge efficiency of the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 to the total discharge port 13 of the housing 10. This allows the fluid ejected from the explosion-proof valve 23 to be discharged from the total discharge port 13 as quickly as possible, increasing the discharge speed of the fluid ejected from the explosion-proof valve 23 and minimizing the residence time of the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 in the flow space 40. To reduce the impact of high-temperature, high-pressure fluid on other battery cells 2, prevent the spread of thermal runaway, and effectively improve the operational safety of the battery pack, the lower separator 313 is also effectively guaranteed in terms of temperature transfer efficiency. When the high-temperature, high-pressure fluid is sprayed onto the lower separator 313, causing its temperature to rise continuously, the adhesive layer 315 can be heated to a temperature sufficient to allow the lower separator 313 to separate from the bottom protective plate 11 of the battery pack. This increases the deformability range of the bottom protective plate 11 and prevents the fluid ejected from the explosion-proof valve 23 from breaking through the lower separator 313 and the bottom protective plate 11 of the housing 10, thereby improving the operational safety of the battery pack and its associated electrical equipment. In a specific embodiment, the thickness d mm of the lower separator 313 can be selected from specific values ​​such as 0.5 mm, 1 mm, 1.2 mm, 1.5 mm, and 2 mm, and is not limited here.

[0057] Furthermore, such as Figures 2 to 6 As shown, in one embodiment of this application, the partition 31 further includes two end partitions 312 located on both sides of the middle partition 311 to form an opening 314 between the ends of the two end partitions 312 away from the middle partition 311; the partition 31 is configured to allow the fluid ejected from the explosion-proof valve 23 to flow out from the opening 314 in the same direction.

[0058] Since the partition 31 includes a central partition 311 and two end partitions 312 located on both sides of the central partition 311, forming an opening 314 between the ends of the two end partitions 312 away from the central partition 311, the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 can flow out through the opening 314, effectively restricting the flow direction of the high-temperature and high-pressure fluid. Furthermore, since the partition 31 allows the fluid ejected from the explosion-proof valve 23 to flow out of the opening 314 in the same direction, after the fluids ejected from the explosion-proof valves 23 of different battery cells 2 flow out of the opening 314 in the same direction, they can be blocked by another partition 31, thus bypassing the area below the explosion-proof valves 23 of other battery cells 2, i.e., the internal area of ​​the partition 31. This ensures that other battery cells 2 are not affected by the high-temperature and high-pressure fluid and can operate normally, preventing thermal runaway propagation and improving the operational safety of the battery pack.

[0059] like Figure 6 As shown, in one embodiment of this application, the projected area of ​​the adhesive layer 315 on the bottom protective plate 11 is s(1) mm. 2 The projected area of ​​the explosion-proof valve 23 on the bottom protective plate 11 is s(3) mm. 2 , s(1) / s(3) satisfies 0.55≤s(1) / s(3)≤0.98.

[0060] The projected area s(1) mm of the adhesive layer 315 on the bottom protective plate 11 2 The projected area s(3) mm of the explosion-proof valve 23 on the bottom protective plate 11 2 When the ratio s(1) / s(3) is less than 0.55, the coverage area of ​​the adhesive layer 315 is low, and the adhesive layer 315 cannot guarantee the bonding strength between the partition 31 and the bottom protective plate 11. The projected area s(1) mm of the adhesive layer 315 on the bottom protective plate 11 is... 2 The projected area s(3) mm of the explosion-proof valve 23 on the bottom protective plate 11 2 When the ratio s(1) / s(3) is greater than 0.98, it is difficult to ensure that the fluid sprayed by the explosion-proof valve 23 can be sprayed to the corresponding area of ​​the adhesive layer 315. It is easy for the adhesive layer 315 in some areas to reach the melting point under the heating effect of the fluid sprayed by the explosion-proof valve 23, while the adhesive layer 315 in some areas does not reach the melting point and remains in a solid state, which makes it difficult for the partition 31 to separate from the bottom plate 11 of the battery pack quickly.

[0061] Therefore, the projected area s(1) mm of the adhesive layer 315 on the bottom protective plate 11 2 The projected area s(3) mm of the explosion-proof valve 23 on the bottom protective plate 11 2 When the ratio s(1) / s(3) satisfies 0.55≤s(1) / s(3)≤0.98, it can ensure the bonding strength between the partition 31 and the bottom cover plate 11, and prevent separation between the partition 31 and the bottom cover plate 11 after the battery pack has been working normally for a long time. It can also ensure that the adhesive layer 315 in the corresponding area can reach the melting point under the heating effect of the fluid sprayed from the explosion-proof valve 23, so that the partition 31 and the bottom cover plate 11 of the battery pack can be separated quickly. In a specific embodiment, the projected area s(1) mm of the adhesive layer 315 on the bottom cover plate 11 is 0.55≤s(1) / s(3)≤0.98. 2 The projected area s(3) mm of the explosion-proof valve 23 on the bottom protective plate 11 2 The ratio s(1) / s(3) can be selected from specific values ​​such as 0.55, 0.6, 0.7, 0.9, 0.98, etc., without any restrictions.

[0062] like Figure 3As shown, in one embodiment of this application, the distance between the lower separator 313 and the explosion-proof valve 23 in the height direction of the battery body 2 is r mm, where r mm satisfies 4 mm ≤ r mm ≤ 15 mm. When the distance r mm between the lower separator 313 and the explosion-proof valve 23 is less than 4 mm, the fluid ejected after the explosion-proof valve 23 ruptures will cause significant damage to the lower separator 313 when it sprays downwards, potentially leading to deformation or even melting of the lower separator 313 due to the impact of at least part of the fluid ejected from the explosion-proof valve 23. When the distance r mm between the lower separator 313 and the explosion-proof valve 23 is greater than 15 mm, it tends to occupy too much space, thereby reducing the energy density of the battery pack in this embodiment of the application.

[0063] When the distance r mm between the lower partition 313 and the explosion-proof valve 23 satisfies 4 mm ≤ r mm ≤ 15 mm, it can be ensured that the impact of at least part of the fluid ejected from the explosion-proof valve 23 on the lower partition 313 is small, and the energy density of the battery pack in this embodiment can be effectively improved. In specific embodiments, the distance r mm between the lower partition 313 and the explosion-proof valve 23 can be selected from specific values ​​such as 4 mm, 5 mm, 8 mm, 12 mm, and 15 mm, and is not limited here.

[0064] Furthermore, such as Figures 2 to 6 As shown, in an embodiment of this application, the battery pack 20 includes at least one battery row 29. When the battery row 29 includes multiple battery bodies 2 arranged along a first direction, in one embodiment of this application, the openings 314 of the partition members 31 are all oriented towards the negative direction of the first direction. It is understood that the negative direction and the positive direction are two pointing directions of any given direction; please refer to the accompanying drawings for specific directions.

[0065] Since the openings 314 of the partition members 31 are all oriented towards the negative direction of the first direction, and the main outlet 13 is located on the side of the housing 10 in the negative direction of the first direction, the partition members 31 can allow the fluid ejected from the explosion-proof valve 23 to flow out in the negative direction of the first direction. After being blocked by another partition member 31 and bypassing the area below the explosion-proof valve 23 of other battery bodies 2, it continues to flow in the negative direction of the first direction until it is discharged from the main outlet 13 located on the side of the housing 10 in the negative direction of the first direction to the outside of the battery pack. Therefore, the above structure can effectively improve the discharge speed of the fluid ejected from the explosion-proof valve 23, minimize the residence time of the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 in the flow space 40, reduce the impact of the high-temperature and high-pressure fluid on other battery bodies 2, effectively control the thermal runaway of the battery body 2, prevent the spread of thermal runaway, and effectively improve the working safety of the battery pack.

[0066] like Figure 5As shown, in one embodiment of this application, an arc-shaped transition portion is provided between the middle partition 311 and the end partition 312.

[0067] like Figure 6 As shown, in one embodiment of this application, the overall outline of the middle partition 311 and the two end partitions 312 on both sides is a U-shaped structure with an opening on one side. That is, the middle partition 311 and the two end partitions 312 on both sides can smoothly transition, and an opening 314 is formed on the opening side of the U-shaped structure. After the fluid ejected from the explosion-proof valve 23 flows out in the negative direction of the first direction under the action of the corresponding baffle 31, it is blocked by another baffle 31 to bypass the area below the explosion-proof valve 23 of other battery bodies 2. In the process, the flow rate of the high-temperature and high-pressure fluid will not drop significantly, thereby effectively increasing the discharge speed of the fluid ejected from the explosion-proof valve 23, further reducing the residence time of the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 in the flow space 40, so as to reduce the impact of the high-temperature and high-pressure fluid on other battery bodies 2 and further prevent the spread of thermal runaway.

[0068] like Figure 5 As shown, in one embodiment of this application, the housing 10 is provided with a main outlet 13, which is connected to the flow space 40. Therefore, the baffle 31 can allow the fluid ejected from the explosion-proof valve 23 to flow out, be blocked by another baffle 31 and bypass the area below the explosion-proof valve 23 of other battery bodies 2, and continue to flow until the fluid is discharged outside the battery pack through the main outlet 13 on the housing 10.

[0069] This application also provides an electrical device that includes at least one of the aforementioned battery packs. It is understood that this electrical device can be any type of electrical device, such as an electric vehicle, an appliance with a battery pack, or an energy storage device, and is not limited thereto.

[0070] It should be noted that the elements described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this application will not describe the various possible combinations separately.

[0071] It should be understood that multiple components and / or parts can be provided by a single integrated component or part. Alternatively, a single integrated component or part can be divided into multiple separate components and / or parts. The use of the public designation "a" or "an" to describe a component or part does not imply the exclusion of other components or parts.

[0072] It should be understood that while terms such as "first" or "second" may be used in this application to describe various elements, these elements are not limited by these terms; these terms are merely used to distinguish one element from another. The terminology used in one or more embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the scope of one or more embodiments of this application. The singular forms "a," "the," and "the" as used in one or more embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used in one or more embodiments of this application refers to and includes any or all possible combinations of one or more associated listed items.

[0073] In this document, terms such as "up," "down," "front," "back," "left," and "right" are used only to indicate the relative positional relationship between related parts, and not to define the absolute position of these related parts. Terms such as "equal" and "same" are not strict mathematical and / or geometric limitations, and also include errors that are understandable to those skilled in the art and permissible in manufacturing or use. Unless otherwise stated, numerical ranges in this document include not only the entire range within its two endpoints, but also several subranges contained therein.

[0074] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of the embodiments of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0075] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A battery pack, characterized in that, include: The battery pack (20) includes a plurality of battery bodies (2) arranged in a row, and an explosion-proof valve (23) is provided on the bottom surface of the battery body (2). A heat exchange plate (30) is disposed at the bottom of the battery pack (20) and is configured to exchange heat with the battery body (2). The heat exchange plate (30) is provided with a through-hole corresponding to the position of the explosion-proof valve (23). The box (10) is provided with a bottom guard plate (11), and a flow space (40) is formed between the bottom guard plate (11) and the heat exchange plate (30). Among them, a baffle (31) is provided on the bottom surface of the heat exchange plate (30). The baffle (31) is located at the through-hole of the heat exchange plate (30), and the baffle (31) has a flow guide cavity communicating with the through-hole. The opening of the flow guide cavity communicates the flow guide cavity and the flow space, so that the fluid ejected by the explosion-proof valve (23) is introduced into the flow space (40) through the opening. The partition and the bottom protective plate (11) are provided with an adhesive layer (315). When the battery body (2) is heated and the explosion-proof valve (23) is opened, the adhesive layer allows the partition (31) and the bottom protective plate (11) to be separated from each other.

2. The battery pack according to claim 1, characterized in that, The adhesive layer (315) is configured to melt under the heating action of the fluid ejected from the explosion-proof valve (23), and the melting point is t℃, where t℃ satisfies 100℃≤t℃≤300℃.

3. The battery pack according to claim 2, characterized in that, The bonding strength of the adhesive layer (315) in the solid state is f MPa, where f MPa satisfies 1 MPa ≤ f MPa ≤ 10 MPa.

4. The battery pack according to claim 1, characterized in that, The thickness of the adhesive layer (315) is e mm, where e mm satisfies 0.5 mm ≤ e mm ≤ 3 mm.

5. The battery pack according to claim 1, characterized in that, The partition (31) includes a middle partition (311) and a lower partition (313). The middle partition (311) connects the heat exchange plate (30) and the lower partition (313). The projection of the explosion-proof valve (23) on the bottom guard plate (11) is located within the projection of the lower partition (313) on the bottom guard plate (11). The lower partition (313) is bonded and fixed to the bottom guard plate (11) of the box body (10) by the adhesive layer (315).

6. The battery pack according to claim 5, characterized in that, The projected area of ​​the adhesive layer (315) on the bottom protective plate (11) is s(1) mm. 2 The projected area of ​​the lower partition (313) on the bottom protective plate (11) is s(2) mm. 2 , s(1) / s(2) satisfies 0.5≤s(1) / s(2)≤0.

95.

7. The battery pack according to claim 6, characterized in that, The projected area s(1) mm of the adhesive layer (315) on the bottom protective plate (11) 2 Meets 400 mm 2 ≤s(1) mm 2 ≤1500 mm 2 .

8. The battery pack according to claim 6, characterized in that, The projected area s(2) mm of the lower partition (313) on the bottom protective plate (11) 2 Meets 500 mm 2 ≤s(2) mm 2 ≤1600 mm 2 .

9. The battery pack according to claim 1, characterized in that, The adhesive layer (315) is a structural adhesive.

10. The battery pack according to claim 5, characterized in that, The thickness of the lower partition (313) is d mm, where d mm satisfies 0.5 mm ≤ d mm ≤ 2 mm.

11. The battery pack according to claim 5, characterized in that, The thickness of the adhesive layer (315) is e mm, where e mm satisfies 0.5 mm ≤ e mm ≤ 3 mm.

12. The battery pack according to claim 5, characterized in that, The partition (31) further includes two end partitions (312) located on both sides of the middle partition (311) to form an opening (314) between the ends of the two end partitions (312) away from the middle partition (311); the partition (31) is configured to allow the fluid ejected by the explosion-proof valve (23) to flow out from the opening (314) in the same direction.

13. The battery pack according to claim 12, characterized in that, The battery pack (20) includes at least one battery row (29), the battery row (29) includes a plurality of battery bodies (2) arranged along a first direction; the openings (314) of the partition (31) are all arranged in the negative direction of the first direction.

14. The battery pack according to claim 13, characterized in that, An arc-shaped transition section is provided between the middle partition (311) and the end partition (312).

15. The battery pack according to claim 12, characterized in that, The overall outline of the middle partition (311) and the two end partitions (312) on both sides is a U-shaped structure with the opening on one side.

16. The battery pack according to claim 12, characterized in that, The projected area of ​​the adhesive layer (315) on the bottom protective plate (11) is s(1) mm. 2 The projected area of ​​the explosion-proof valve (23) on the bottom protective plate (11) is s(3) mm. 2 , s(1) / s(3) satisfies 0.55≤s(1) / s(3)≤0.

98.

17. The battery pack according to claim 12, characterized in that, In the height direction of the battery body, the distance between the lower partition (313) and the explosion-proof valve (23) is r mm, where r mm satisfies 4 mm ≤ r mm ≤ 15 mm.

18. The battery pack according to claim 12, characterized in that, The box (10) is provided with a main outlet (13), which is connected to the circulation space (40).

19. An electrical appliance, characterized in that, Includes the battery pack according to any one of claims 1 to 18.

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