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 array, a heat exchange plate and a pack body. The battery array comprises a plurality of battery monomers arranged in an array. An explosion-proof valve is arranged on the bottom surface of the battery monomer. The heat exchange plate is arranged at the bottom of the battery array and is configured to exchange heat with the battery monomer. A through hole corresponding to the position of the explosion-proof valve is arranged on the heat exchange plate. The pack body is provided with a bottom guard plate. An exhaust space is enclosed between the bottom guard plate and the heat exchange plate. The upper surface of the bottom guard plate is provided with a flow guide piece. The position of the flow guide piece on the bottom guard plate corresponds to the position of the explosion-proof valve. The flow guide piece, the bottom guard plate and the heat exchange plate jointly enclose a flow guide cavity which is only open to one side. The opening directions of adjacent flow guide cavities are the same. The flow guide piece can make the fluid sprayed by the explosion-proof valve move in the direction of the opening direction of the flow guide cavity and be blocked by another flow guide piece, so as to bypass the area below the explosion-proof valve of other battery monomers.

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 the existing thermal-electric separation design of battery packs, the explosion-proof valve is located at the bottom of the battery. When the explosion-proof valve ruptures due to thermal runaway of a battery, the fluid ejected from the explosion-proof valve has a relatively high temperature and pressure. The high-temperature and high-pressure fluid flows along the exhaust space between the battery and the bottom guard plate, which can easily affect adjacent batteries and thus trigger secondary thermal runaway. 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 after the explosion-proof valve ruptures due to thermal runaway of the battery, the fluid ejected from the explosion-proof valve has a relatively high temperature and pressure. The high-temperature and high-pressure fluid flows along the exhaust space between the battery and the bottom guard plate, which can easily affect adjacent batteries and thus cause secondary thermal runaway.

[0004] The first aspect of this application provides a battery pack, comprising: A battery array comprising multiple 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 array and is configured to exchange heat with the individual battery cells. The heat exchange plate is provided with a through-hole corresponding to the position of the explosion-proof valve; The package body is provided with a bottom protective plate, and an exhaust space is formed between the bottom protective plate and the heat exchange plate; The bottom guard plate has a flow guide on its upper surface. The position of the flow guide on the bottom guard plate corresponds to the position of the explosion-proof valve. The flow guide, the bottom guard plate and the heat exchange plate together form a flow guide cavity that is open to only one side, and the opening direction of adjacent flow guide cavities is the same.

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

[0006] During the operation of the battery pack in this embodiment, the fluid ejected after the explosion-proof valve of any battery cell ruptures can be discharged downwards through the through-hole to the exhaust space between the bottom guard plate and the heat exchange plate of the pack. Since a guide is provided on the upper surface of the bottom guard plate near the position corresponding to the explosion-proof valve, the position of the guide on the bottom guard plate corresponds to the position of the explosion-proof valve, and the guide, the bottom guard plate and the heat exchange plate together form a guide cavity that is only open to one side, and the opening direction of adjacent guide cavities is the same. The guide can make the fluid ejected from the explosion-proof valve move in the direction of the opening of the guide cavity. When at least part of the fluid ejected from the explosion-proof valve moves in the direction of the opening of the guide cavity, it will be blocked by another guide, thereby bypassing the area below the explosion-proof valve of other battery cells, preventing the high-temperature and high-pressure fluid from flowing to the area below the explosion-proof valve of adjacent battery cells, ensuring that adjacent battery cells are not affected by the high-temperature and high-pressure fluid, effectively controlling the secondary thermal runaway of adjacent battery cells, preventing the spread of thermal runaway, and effectively improving the working safety of the battery pack. 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 perspective view of the battery pack according to an embodiment of this application.

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

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

[0016] Figure 7 This is a partial structural diagram of the battery pack according to an embodiment of this application.

[0017] Figure 8This is a partial structural diagram of the battery pack according to an embodiment of this application.

[0018] Attached image labels: 10. Package body; 11. Bottom protective plate; 12. Frame; 13. Main exhaust port; 14. Flow guide; 141. Main flow section; 142. Side flow guide; 144. Air outlet; 145. Flow guide cavity; 20. Battery array; 2. Battery cell; 21. Housing; 22. Cover plate; 23. Explosion-proof valve; 29. ​​Battery row; 30. Heat exchange plate; 32. Flow channel; 40. Exhaust space.

[0019] X - First direction; Y - Second direction; Z - Height direction. Detailed Implementation

[0020] 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.

[0021] 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.

[0022] like Figures 1 to 8 As shown in the figure, this application embodiment provides a battery pack, including a pack body 10, a battery array 20, and a heat exchange plate 30. The pack body 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.

[0023] The battery pack of this embodiment comprises a battery array 20, a battery management system, a thermal management system, an electrical connection system, structural components, and protective components, all housed within a pack body 10 and sealed by a cover plate 22, forming a complete functional unit capable of directly outputting electrical energy. The battery array 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, with both the battery cells 2 and the isolation plate located within the pack body 10. The isolation plate is located on the side of the battery cell 2 furthest from the bottom protective plate 11 of the pack body 10, separating the battery cell 2 from other components located above it, thus providing isolation. Specifically, the aforementioned pack body 10 can be a closed or semi-closed structure made of materials such as metal or plastic, serving as the physical carrier of the battery array 20. Its design and manufacturing must meet the safety, reliability, and functional requirements of the battery pack under different usage scenarios. The housing 10 provides installation space for the battery array 20, BMS, cooling system, electrical connection components, etc., and fixes these components inside the housing 10 through reasonable structural design, ensuring that they maintain a relatively stable position during battery pack operation and avoiding damage to components or loosening of connections due to vibration, impact or other factors.

[0024] The package 10 may include a lower package and an upper package. The lower package includes a bottom protective plate 11 and a frame 12 connected to and surrounding the bottom protective plate 11. The upper package is connected to the frame 12 and has a cover plate 22 opposite to the bottom protective plate 11. The upper and lower packages 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 package 10 is a cube, the frame 12 of the lower package generally has four side plates, which surround the periphery of the bottom protective plate 11. In other embodiments, the shape of the package 10 may also be a cylinder or other shapes. The frame 12 mainly serves to support, protect, and connect. The frame 12 may be formed by splicing multiple beams together. The frame 12 may be rectangular, circular, polygonal, etc., without limitation. The beams of the frame 12 may have a solid structure 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 array 20, battery management system, cooling system and other components inside the battery pack. The pack body 10 can be cast from materials such as steel and aluminum alloy, or lightweight materials such as glass fiber reinforced composite material and carbon fiber reinforced composite material.

[0025] like Figure 1As shown, the battery array 20 is disposed in the receiving cavity. The battery array 20 includes a plurality of battery cells 2 arranged in a row. An explosion-proof valve 23 is disposed on the bottom surface of the battery cell 2.

[0026] Understandably, multiple battery cells 2 with similar capacity and internal resistance are connected in series or parallel to form a battery array 20. Each battery cell 2 can store chemical energy and controllably convert it into electrical energy. In a recyclable battery, the active materials can be reactivated by charging after discharge for continued use. Each battery cell 2 includes at least a housing 21 and a cover plate 22 fixedly connected to each other, as well as a battery cell and electrolyte. The housing 21 and cover plate 22 together house the battery cell 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 in other ways such as bonding or riveting, the connection can be a different structure. Understandably, 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 the electrode assembly has a tab, and one end of an adapter piece is electrically connected to the tab, while the other end is electrically connected to a terminal post. It is understood that the battery cell 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.

[0027] 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 a single battery cell 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, and alloys. 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.

[0028] Since an explosion-proof valve 23 is installed on the bottom surface of the battery cell 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 cell 2, so as to achieve thermal and electrical separation and improve the overall safety of the battery pack.

[0029] The heat exchange plate 30 is disposed at the bottom of the battery array 20 and is configured to exchange heat with the battery cell 2; specifically, the heat exchange plate 30 is attached to the bottom surface of the battery cell 2 and can heat and / or cool the battery cell 2 as needed.

[0030] The heat exchange plate 30 is a component for regulating the temperature of the battery cell 2. The heat exchange plate 30 has an internal heat exchange channel 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 has an inlet and an outlet for the heat exchange medium. The medium enters the channel through the inlet, exchanges heat with the battery cell 2, and then exits through the outlet, thus achieving heat exchange for the battery cell 2. The heat exchange plate 30 can be made of a material with high thermal conductivity, such as copper; alternatively, it can have a heat pipe inside, which can rapidly transfer heat through the principle of thermal convection; or it can have a channel inside, connecting to a heating or cooling device, through which a liquid medium flows, enabling efficient heat exchange. The heat exchange plate 30 may include a heating element and an electrical connector. The heating element can be a heating wire, a heating film, or a heating plate; this application does not impose any limitations. The heat exchange plate 30 can be made of metal materials, such as aluminum alloy or magnesium alloy; or it can be made of plastic.

[0031] like Figure 2 As shown, in one embodiment of this application, the heat exchange plate 30 is provided with at least one flow channel 32, through which a heat exchange liquid flows to exchange heat with the battery cell 2. Because the heat exchange plate 30 has at least one flow channel 32, through which a heat exchange liquid flows to exchange heat with the battery cell 2, the heat exchange plate 30 can utilize the flowing heat exchange liquid for heat exchange, ensuring that the battery cell 2 operates within its optimal operating range. It is understood that the heat exchange liquid can be water, oil, an aqueous solution of ethylene glycol, etc., and is not limited thereto.

[0032] like Figure 4 As shown, the heat exchange plate 30 is provided with a through-hole corresponding to the position of the explosion-proof valve 23; an exhaust space 40 is formed between the bottom protective plate 11 of the package 10 and the heat exchange plate 30. In this way, since 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 of the heat exchange plate 30 to the exhaust space 40 between the bottom protective plate 11 of the package 10 and the heat exchange plate 30, and then discharged outside the battery pack.

[0033] Among them, such as Figure 5As shown, a flow guide 14 is provided on the upper surface of the bottom guard plate 11. The position of the flow guide 14 on the bottom guard plate 11 corresponds to the position of the explosion-proof valve 23. The flow guide 14, the bottom guard plate 11 and the heat exchange plate 30 together form a flow guide cavity 145 that is open to only one side, and the opening direction of adjacent flow guide cavities 145 is the same.

[0034] Therefore, during the operation of the battery pack in this embodiment, the fluid ejected after the explosion-proof valve 23 of any battery cell 2 ruptures can be discharged downwards through the through-hole to the exhaust space 40 between the bottom guard plate 11 and the heat exchange plate 30 of the pack body 10; since a guide member 14 is provided on the upper surface of the bottom guard plate 11 near the position corresponding to the explosion-proof valve 23, the position of the guide member 14 on the bottom guard plate 11 corresponds to the position of the explosion-proof valve 23, and the guide member 14, the bottom guard plate 11, and the heat exchange plate 30 together form a guide cavity 145 that is only open to one side, and the opening direction of adjacent guide cavities 145 is the same, the guide... The flow guide 14 enables the fluid ejected from the explosion-proof valve 23 to move in the direction of opening of the flow guide cavity 145. When at least part of the fluid ejected from the explosion-proof valve 23 moves in the direction of opening of the flow guide cavity 145, it will be blocked by another flow guide 14, thereby bypassing the area below the explosion-proof valve 23 of other battery cells 2. This prevents the high-temperature and high-pressure fluid from flowing to the area below the explosion-proof valve 23 of other battery cells 2, ensuring that other battery cells 2 will not be affected by the high-temperature and high-pressure fluid and will work normally. This can effectively control the thermal runaway of battery cells 2, prevent the spread of thermal runaway, and effectively improve the working safety of the battery pack.

[0035] In one embodiment of this application, the flow guide 14 and the bottom protective plate 11 are integrally formed. Since the flow guide 14 and the bottom protective plate 11 are integrally formed, they can be processed in the same processing step, thereby further improving the processing efficiency of the flow guide 14.

[0036] In another embodiment of this application, the flow guide 14 is welded and fixed to the bottom protective plate 11 of the package body 10. That is, since the flow guide 14 is welded and fixed to the bottom protective plate 11 of the package body 10, the fixed connection strength between the flow guide 14 and the bottom protective plate 11 can be improved, thereby improving the structural stability of the bottom protective plate 1111.

[0037] like Figure 6 As shown, in one embodiment of this application, the extension height of the guide member 14 in the height direction of the battery cell 2 is a mm, where a mm satisfies 3 mm ≤ a mm ≤ 12 mm.

[0038] In the height direction, when the extension height a mm of the guide member 14 is less than 3 mm, the obstruction and diversion effect of the guide member 14 is poor, which easily leads to some fluid ejected from the explosion-proof valve 23 not being blocked by the guide member 14, thereby reducing the obstruction and diversion effect of the guide member 14. In the height direction, when the extension height a mm of the guide member 14 is greater than 12 mm, not only is the overall height of the exhaust space 40 larger, which easily leads to a decrease in the energy density of the battery pack in this embodiment, but also increases the material cost required for the guide member 14. Therefore, when the extension height a mm of the guide member 14 satisfies 3 mm ≤ a mm ≤ 12 mm, the obstruction and diversion effect of the guide member 14 can be guaranteed, the energy density of the battery pack in this embodiment can be effectively improved, and the material cost required for the guide member 14 can be reduced. In specific embodiments, the extension height a mm of the guide member 14 can be selected from specific values ​​such as 3 mm, 5 mm, 6 mm, 8 mm, 12 mm, etc., and is not limited here.

[0039] like Figure 6 As shown, in one embodiment of this application, the distance between the bottom protective plate 11 and the explosion-proof valve 23 in the height direction of the battery cell 2 is b mm, where b mm satisfies 5 mm ≤ b mm ≤ 15 mm.

[0040] When the distance b mm between the bottom protective plate 11 and the explosion-proof valve 23 is less than 5 mm in the height direction, the overall height of the exhaust space 40 is relatively low. When the ejected fluid, such as the ejected material, is ejected downwards after the explosion-proof valve 23 ruptures, it causes significant damage to the bottom protective plate 11, potentially leading to deformation or even melting of the bottom protective plate 11 due to the impact of at least part of the fluid ejected from the explosion-proof valve 23. When the distance b mm between the bottom protective plate 11 and the explosion-proof valve 23 is greater than 15 mm in the height direction, the overall height of the exhaust space 40 is relatively high, which can easily lead to a decrease in the energy density of the battery pack in this embodiment.

[0041] Therefore, when the distance b mm between the bottom protective plate 11 and the explosion-proof valve 23 in the height direction satisfies 5 mm ≤ b mm ≤ 15 mm, the impact of the fluid ejected from the explosion-proof valve 23 on the bottom protective plate 11 can be reduced, and the energy density of the battery pack in this embodiment can be effectively improved. In specific embodiments, the distance b mm between the bottom protective plate 11 and the explosion-proof valve 23 can be selected from specific values ​​such as 5 mm, 6 mm, 8 mm, 12 mm, and 15 mm, and is not limited here.

[0042] like Figure 7 As shown, in one embodiment of this application, the projected area of ​​the explosion-proof valve 23 on the bottom protective plate 11 is s mm. 2 The projected area of ​​the flow guide cavity 145 on the bottom protective plate 11 is r mm. 2The s / r ratio satisfies 0.5 ≤ s / r ≤ 0.9.

[0043] The projected area s mm of the explosion-proof valve 23 on the bottom protective plate 11 2 The projected area r mm of the flow guide cavity 145 on the bottom protective plate 11 2 When the ratio s / r is less than 0.5, the projected area of ​​the flow guide cavity 145 on the bottom guard plate 11 is large, which increases the material cost required for the flow guide 14.

[0044] The projected area s mm of the explosion-proof valve 23 on the bottom protective plate 11 2 The projected area r mm of the flow guide cavity 145 on the bottom protective plate 11 2 When the ratio s / r is greater than 0.9, some of the fluid ejected from the explosion-proof valve 23 is more likely to be ejected into the area outside the flow guide cavity 145, reducing the flow blocking and guiding effect of the flow guide 14.

[0045] Therefore, the projected area s mm of the explosion-proof valve 23 on the bottom protective plate 11 2 The projected area r mm of the flow guide cavity 145 on the bottom protective plate 11 2 When the ratio s / r satisfies 0.5≤s / r≤0.9, the flow guiding effect of the guide component 14 can be guaranteed, while effectively saving the material cost required for the guide component 14. In a specific embodiment, the projected area s mm of the explosion-proof valve 23 on the bottom protective plate 11 is... 2 The projected area r mm of the flow guide cavity 145 on the bottom protective plate 11 2 The ratio s / r can be selected from specific values ​​such as 0.5, 0.6, 0.7, 0.75, 0.9, etc., and there are no restrictions here.

[0046] like Figure 5 As shown, in one embodiment of this application, the flow guide 14 includes a main flow section 141 and two side flow guide sections 142 located on both sides of the main flow section 141. The main flow section 141 and the two side flow guide sections 142 are both disposed on the bottom protective plate 11, so that they can jointly form a flow guide cavity 145 open to the air outlet 144, so that the fluid ejected from the explosion-proof valve 23 flows out from the air outlet 144 in the same direction. After the fluid ejected from the explosion-proof valve 23 flows out from the air outlet 144 in the same direction, it can be blocked by another flow guide 14 to bypass the area below the explosion-proof valve 23 of other battery cells 2, that is, the internal area of ​​the flow guide 14, so as to ensure that other battery cells 2 will not be affected by the high temperature and high pressure fluid and work normally, prevent thermal runaway propagation, and improve the working safety of the battery pack.

[0047] like Figure 7As shown, in one embodiment of this application, the included angle between the side guide section 142 and the main flow section 141 is c°, where c° satisfies 90°≤c°<180°. It can be understood that the included angle c° between the side guide section 142 and the main flow section 141 is a right angle or an obtuse angle. Thus, the side guide section 142 and the main flow section 141 can together form a guide cavity 145 that opens towards the air outlet 144. The fluid ejected from the explosion-proof valve 23 flows out of the air outlet 144 in a relatively consistent direction, while less fluid flows out on both sides of the open direction of the guide cavity 145.

[0048] Furthermore, in one embodiment of this application, the included angle c° between the side guide portion 142 and the main flow portion 141 satisfies 100°≤c°<150°. When the included angle c° between the side guide portion 142 and the main flow portion 141 satisfies 100°≤c°<150°, it can be further ensured that the fluid ejected from the explosion-proof valve 23 flows out of the outlet 144 in a basically consistent direction, and the proportion of fluid flowing out on both sides of the open direction of the guide cavity 145 is relatively small.

[0049] like Figure 7 As shown, in one embodiment of this application, the extension length of the main flow section 141 is e mm, where e mm satisfies 15 mm ≤ e mm ≤ 60 mm. When the extension length e mm of the main flow section 141 is less than 15 mm, the overall flow guiding effect of the guide member 14 is poor, and it cannot guarantee the directional movement of the guide cavity 145 in the opening direction; when the extension length e mm of the main flow section 141 is greater than 60 mm, it can easily affect the arrangement of the flow channel 32 or other structures of the heat exchange plate 30.

[0050] Therefore, in the battery pack of this application embodiment, when the extension length e mm of the main flow section 141 satisfies 15 mm ≤ e mm ≤ 60 mm, it can ensure the flow guiding effect of the flow guide 14, allowing the fluid ejected from the explosion-proof valve 23 to move in the direction of the opening of the flow cavity 145 under the action of the flow guide 14. It also facilitates the arrangement of the flow channel 32 or other structures of the heat exchange plate 30, thereby ensuring that the heat exchange area between the flow channel 32 and the bottom surface of the battery cell 2 meets the requirements, and thus ensuring the heat exchange efficiency between the flow channel 32 and the battery cell 2. In specific embodiments, the extension length e mm of the main flow section 141 can be selected from specific values ​​such as 15 mm, 20 mm, 30 mm, 40 mm, 60 mm, etc., and is not limited here.

[0051] like Figure 7As shown, in one embodiment of this application, the extension length of the side guide portion 142 is f mm, where f mm satisfies 15 mm ≤ f mm ≤ 35 mm. When the extension length f mm of the side guide portion 142 is less than 15 mm, the guiding effect of the side guide portion 142 is poor, and some of the fluid ejected from the explosion-proof valve 23 will flow out along both sides of the side guide portion 142 in the opening direction of the guide cavity 145; when the extension length f mm of the side guide portion 142 is greater than 35 mm, it can easily affect the arrangement of the flow channel 32 or other structures of the heat exchange plate 30.

[0052] Therefore, when the extension length f mm of the side guide section 142 satisfies 15 mm ≤ f mm ≤ 35 mm, it can ensure the guiding effect of the side guide section 142, ensuring that the fluid ejected from the explosion-proof valve 23 flows out of the outlet 144 in a basically consistent direction, and that the proportion of fluid flowing out on both sides of the open direction of the guide cavity 145 is small. It also facilitates the arrangement of the flow channel 32 or other structures of the heat exchange plate 30, thereby ensuring that the heat exchange area between the flow channel 32 and the bottom surface of the battery cell 2 meets the requirements, and thus ensuring the heat exchange efficiency between the flow channel 32 and the battery cell 2. In a specific embodiment, the extension length f mm of the side guide section 142 can be selected from specific values ​​such as 15 mm, 20 mm, 24 mm, 30 mm, 35 mm, etc., and is not limited here.

[0053] In one embodiment of this application, an arc-shaped transition portion is provided between the side guide portion 142 and the main guide portion 141.

[0054] Because an arc-shaped transition section is provided between the side guide section 142 and the main guide section 141, at least part of the fluid ejected from the explosion-proof valve 23 moves in the direction of the opening of the guide cavity 145 under the action of the corresponding guide member 14. 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 and further reducing the residence time of the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 in the exhaust space 40, so as to reduce the impact of the high-temperature and high-pressure fluid on other battery cells 2 and further prevent the spread of thermal runaway.

[0055] Furthermore, such as Figure 7 As shown, in one embodiment of this application, the main flow section 141 and two side flow sections 142 located on both sides of the main flow section 141 form an isosceles trapezoidal flow guide cavity 145, and the air outlet 144 is located at the lower bottom edge of the trapezoidal flow guide cavity 145. Thus, since the main flow section 141 and the two side flow sections 142 form an isosceles trapezoidal flow guide cavity 145, the flow guide member 14 can direct the fluid ejected from the explosion-proof valve 23 in the direction of opening of the flow guide cavity 145, out of the air outlet 144 located at the lower bottom edge of the trapezoidal flow guide cavity 145.

[0056] like Figure 7 As shown, in one embodiment of this application, the distance between the main flow section 141 and the explosion-proof valve 23 of the corresponding battery cell 2 is k mm, where k mm satisfies 3 mm ≤ k mm ≤ 15 mm.

[0057] When the distance k mm between the main flow section 141 and the explosion-proof valve 23 of the corresponding battery cell 2 is less than 3 mm, interference is likely to occur between them. If there is partial misalignment between the main flow section 141 and the explosion-proof valve 23, the main flow section 141 may enter the corresponding area below the explosion-proof valve 23, causing the flow guide 14 to fail to perform its flow guiding function properly. When the distance k mm between the main flow section 141 and the explosion-proof valve 23 of the corresponding battery cell 2 is greater than 15 mm, it may affect the arrangement of the flow channel 32 or other structures of the heat exchange plate 30.

[0058] Therefore, when the distance k mm between the main flow section 141 and the explosion-proof valve 23 of the corresponding battery cell 2 satisfies 3 mm ≤ k mm ≤ 15 mm, it can both avoid mutual interference between the two and ensure that the main flow section 141 is located on the side below the explosion-proof valve 23, facilitating the normal functioning of the main flow section 141 in guiding the flow; it can also facilitate the arrangement of the flow channel 32 or other structures of the heat exchange plate 30, thereby ensuring that the heat exchange area between the flow channel 32 and the bottom surface of the battery cell 2 meets the requirements, and thus ensuring the heat exchange efficiency between the flow channel 32 and the battery cell 2. In a specific embodiment, the distance k mm between the main flow section 141 and the explosion-proof valve 23 of the corresponding battery cell 2 can be selected from specific values ​​such as 3 mm, 5 mm, 6 mm, 10 mm, 15 mm, etc., and is not limited here.

[0059] like Figure 8 As shown, in one embodiment of this application, at least one flow channel 32 is provided in the heat exchange plate 30, and heat exchange liquid flows in the flow channel 32 to exchange heat with the battery cell 2. In this case, the projection of the guide member 14 on the bottom protective plate 11 is located inside the projection of the flow channel 32 on the bottom protective plate 11. Since the projection of the guide member 14 on the bottom protective plate 11 is located inside the projection of the flow channel 32 on the bottom protective plate 11, it is convenient to ensure that the height of the guide member 14 is consistent throughout and that it abuts against the bottom surface of the flow channel 32, preventing gaps between the guide member 14 and the bottom surface of the flow channel 32, and improving the guiding effect of the guide member 14.

[0060] like Figure 1 As shown, in one embodiment of this application, a total vent 13 is provided on the package 10, and the total vent 13 is located on the side of the package 10; the flow guide 14 is configured to cause the fluid ejected by the explosion-proof valve 23 to flow out from the vent 144 in the direction of the total vent 13.

[0061] By providing a main vent 13 on the side of the pack body 10, the guide member 14 can direct the fluid ejected from the explosion-proof valve 23 to flow in the direction of the opening of the guide cavity 145. After being blocked by another guide member 14 and bypassing the area below the explosion-proof valve 23 of other battery cells 2, it continues to flow until it is discharged from the main vent 13 located on the side of the pack body 10 to the outside of the battery pack. This effectively increases the discharge speed of the fluid ejected from the explosion-proof valve 23, minimizes the residence time of the high-temperature and high-pressure fluid ejected from the explosion-proof valve 23 in the exhaust space 40, reduces the impact of the high-temperature and high-pressure fluid on other battery cells 2, effectively controls the thermal runaway of the battery cells 2, prevents the spread of thermal runaway, and effectively improves the working safety of the battery pack.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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: A battery array (20) includes multiple battery cells (2) arranged in a row, and an explosion-proof valve (23) is provided on the bottom surface of each battery cell (2). A heat exchange plate (30) is disposed at the bottom of the battery array (20) and is configured to exchange heat with the battery cells (2); the heat exchange plate (30) is provided with a through-hole corresponding to the position of the explosion-proof valve (23); Package (10), the package (10) is provided with a bottom guard plate (11), and an exhaust space (40) is formed between the bottom guard plate (11) and the heat exchange plate (30). The bottom guard plate (11) is provided with a flow guide (14) on its upper surface. The position of the flow guide (14) on the bottom guard plate (11) corresponds to the position of the explosion-proof valve (23). The flow guide (14), the bottom guard plate (11) and the heat exchange plate (30) together form a flow guide cavity that is open to only one side, and the opening direction of adjacent flow guide cavities is the same.

2. The battery pack according to claim 1, characterized in that, The flow guide (14) is integrally formed with the bottom guard plate (11).

3. The battery pack according to claim 1, characterized in that, The flow guide (14) is welded and fixed to the bottom protective plate (11) of the package body (10).

4. The battery pack according to claim 3, characterized in that, In the height direction of the battery cell, the extension height of the guide (14) is a mm, where a mm satisfies 3 mm ≤ a mm ≤ 12 mm.

5. The battery pack according to claim 1, characterized in that, In the height direction of the battery cell, the distance between the bottom protective plate (11) and the explosion-proof valve (23) is b mm, where b mm satisfies 5 mm ≤ b mm ≤ 15 mm.

6. The battery pack according to claim 1, characterized in that, The projected area of ​​the explosion-proof valve (23) on the bottom protective plate (11) is s mm. 2 The projected area of ​​the flow guiding cavity on the bottom protective plate (11) is r mm. 2 The s / r ratio satisfies 0.5 ≤ s / r ≤ 0.

9.

7. The battery pack according to claim 1, characterized in that, The flow guide (14) includes a main flow section (141) and two side flow guides (142) located on both sides of the main flow section (141). The main flow section (141) and the two side flow guides (142) are all disposed on the bottom guard plate (11) and together form a flow guide cavity open to the air outlet (144) so ​​that the fluid ejected by the explosion-proof valve (23) flows out from the air outlet (144) in the same direction.

8. The battery pack according to claim 7, characterized in that, The angle between the side guide section (142) and the main guide section (141) is c°, where c° satisfies 90°≤c°<180°.

9. The battery pack according to claim 8, characterized in that, The included angle c° between the side guide section (142) and the main guide section (141) satisfies 100°≤c°<150°.

10. The battery pack according to claim 7, characterized in that, The extension length of the main flow section (141) is e mm, where e mm satisfies 15 mm ≤ e mm ≤ 60 mm.

11. The battery pack according to claim 7, characterized in that, The extension length of the side guide (142) is f mm, where f mm satisfies 15 mm ≤ f mm ≤ 35 mm.

12. The battery pack according to claim 7, characterized in that, An arc-shaped transition section is provided between the side guide section (142) and the main guide section (141).

13. The battery pack according to claim 7, characterized in that, The main flow section (141) and the two side flow sections (142) located on both sides of the main flow section (141) form an isosceles trapezoidal flow cavity, and the air outlet (144) is located at the lower bottom edge of the trapezoidal flow cavity.

14. The battery pack according to claim 7, characterized in that, The distance between the main flow section (141) and the explosion-proof valve (23) corresponding to the battery cell (2) is k mm, where k mm satisfies 3 mm ≤ k mm ≤ 15 mm.

15. The battery pack according to claim 7, characterized in that, The heat exchange plate (30) is provided with at least one flow channel (32), and heat exchange liquid flows in the flow channel (32) to exchange heat with the battery cell (2); the projection of the guide member on the bottom guard plate is located inside the projection of the flow channel (32) on the bottom guard plate.

16. The battery pack according to claim 7, characterized in that, The package (10) is provided with a main vent (13), which is located on the side of the package (10); The flow guide (14) is configured to cause the fluid ejected from the explosion-proof valve (23) to flow out from the outlet (144) in the direction of the main exhaust port (13).

17. An electrical appliance, characterized in that, Includes the battery pack according to any one of claims 1 to 16.

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