Battery pack and energy storage device

Abstract

The present application relates to the technical field of energy storage, and solves the problem of high-voltage breakdown and high-voltage sparking of the side plate of a box body when a battery cell is in thermal runaway. The present application discloses a battery pack and an energy storage device. The battery pack comprises: a box body, the box body comprising an upper box cover and a liquid cooling plate, the upper box cover being provided with a containing cavity, the bottom of the upper box cover being provided with an opening communicating with the containing cavity, the liquid cooling plate being sealingly connected to the bottom of the upper box cover and closing the opening, and the upper box cover being an insulating member; and a battery cell, the battery cell being located in the containing cavity and being carried by the liquid cooling plate, and the battery cell being in heat-conducting connection with the liquid cooling plate. In the above battery pack, the battery cell is contained in the containing cavity of the upper box cover and is carried by the liquid cooling plate, the upper box cover is an insulating member, high-voltage breakdown and high-voltage sparking of the battery cell when the battery cell is in thermal runaway are avoided, the cost and weight of the box body can be reduced, the energy density of the battery pack is improved, and the overall cost is also reduced.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to a battery pack and energy storage device. Background Technology

[0002] In related technologies, the battery pack housing consists of a cover plate and a lower housing. The lower housing includes a bottom plate and side plates formed on the bottom plate. The side plates have a certain height and are generally made of metal. When the battery pack experiences thermal runaway, it is very easy for the high-voltage circuit of the internal battery to break down and spark with the metal side plates, causing the metal side plates to melt and break down. Oxygen enters the battery pack, causing a fire and explosion inside the battery pack. Moreover, the metal cover plate is relatively heavy. Summary of the Invention

[0003] The present invention provides a battery pack and an energy storage device to solve at least one of the above-mentioned technical problems.

[0004] A battery pack according to an embodiment of the present invention includes:

[0005] The enclosure includes an upper cover and a liquid cooling plate. The upper cover has a receiving cavity inside, and the bottom of the upper cover has an opening communicating with the receiving cavity. The liquid cooling plate is sealed to the bottom of the upper cover and closes the opening. The upper cover is an insulating component.

[0006] A battery cell, which is located within the receiving cavity and supported by the liquid cooling plate, is thermally connected to the liquid cooling plate.

[0007] In the aforementioned battery pack, the individual battery cells are housed within the cavity of the upper cover and supported by a liquid cooling plate. The upper cover is an insulating component, which prevents the individual battery cells from experiencing high-voltage breakdown and high-voltage arcing during thermal runaway. It also reduces the cost and weight of the enclosure, thereby reducing the weight of the battery pack, increasing the energy density of the battery pack, and lowering the overall cost.

[0008] In some embodiments, the material of the insulating element is selected from at least one of polypropylene, polycarbonate, polyphenylene ether, composites of polycarbonate and glass fiber, acrylonitrile-butadiene-styrene plastic, composites of acrylonitrile-butadiene-styrene plastic and glass fiber, composites of polyphenylene ether and glass fiber, and composites of epoxy resin and glass fiber.

[0009] This allows for flexible selection of the material for the top cover.

[0010] In some embodiments, the upper cover includes multiple mesh structures and filler, the multiple mesh structures being stacked, and the filler filling the gaps in the mesh structures and connecting the multiple mesh structures.

[0011] This ensures the structural strength of the upper casing.

[0012] In some embodiments, the upper cover includes a side panel, the bottom of which is provided with a sealing edge, which is sealed to the liquid cooling plate;

[0013] The sealing edge is connected to the side plate to form a connecting part. The connecting part is configured to rupture and form a gap channel when the air pressure in the receiving cavity exceeds the air pressure threshold. The receiving cavity is connected to the outside of the box through the gap channel.

[0014] This can improve the safety of the battery pack when a single battery cell experiences thermal runaway.

[0015] In some embodiments, the connecting portion has a rounded corner structure.

[0016] This ensures that the connection is easily broken when the battery cell experiences thermal runaway.

[0017] In some embodiments, the upper cover includes a side panel, the bottom of which is provided with a sealing edge;

[0018] The liquid cooling plate has an annular sealing groove, and a sealing ring is placed inside the sealing groove. The sealing edge is connected to the liquid cooling plate, and the sealing ring seals the sealing edge to the liquid cooling plate.

[0019] This ensures the airtight connection between the top cover and the liquid cooling plate.

[0020] In some embodiments, the battery pack satisfies the following relationship:

[0021] c = k * b, where k is the compressible range of the sealing ring, and the value of k ranges from [0.2, 0.4], c is the depth of the sealing groove, and b is the width of the sealing ring.

[0022] This ensures the sealing effect of the sealing ring.

[0023] In some embodiments, the battery pack satisfies the following relationship:

[0024] a = k * d + b, where k is the compressible range of the sealing ring, and the value of k ranges from [0.2, 0.4], a is the width of the sealing groove, b is the width of the sealing ring, and d is the height of the sealing ring.

[0025] This ensures the sealing effect of the sealing ring.

[0026] In some embodiments, the liquid cooling plate includes a sealing plate, a flow channel plate, and a protective plate stacked sequentially from top to bottom. The sealing plate is sealed to the bottom of the upper cover. The flow channel plate includes a first side and a second side facing away from each other. The first side has a first groove, and the sealing plate covers the first groove to form a first flow channel, and / or the second side has a second groove, and the protective plate covers the second groove to form a second flow channel.

[0027] The sealing plate is provided with a first connector and a second connector, which are respectively connected to the two ends of the first flow channel and / or respectively connected to the two ends of the second flow channel.

[0028] In this way, a liquid cooling structure for individual battery cells can be formed.

[0029] In some embodiments, the liquid cooling plate is thermally connected to the bottom surface of the battery cell via thermally conductive adhesive.

[0030] This can improve the heat dissipation efficiency of individual battery cells.

[0031] In some embodiments, a receiving groove is formed on the upper surface of the liquid cooling plate, and the thermally conductive adhesive is contained in the receiving groove.

[0032] This prevents the thermal adhesive from overflowing.

[0033] An energy storage device according to an embodiment of the present invention includes a battery pack according to any of the above embodiments.

[0034] In the aforementioned energy storage device, the battery cells are housed within the cavity of the upper cover and supported by a liquid cooling plate. The upper cover is an insulating component, which prevents the battery cells from experiencing high-voltage breakdown and high-voltage arcing during thermal runaway. It also reduces the cost and weight of the enclosure, lowers the weight of the battery pack, increases the energy density of the battery pack, and reduces the overall cost.

[0035] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0037] Figure 1 This is a perspective view of the battery pack according to an embodiment of the present invention;

[0038] Figure 2 This is an exploded view of the battery pack according to an embodiment of the present invention;

[0039] Figure 3 This is a side view of the battery pack according to an embodiment of the present invention;

[0040] Figure 4 for Figure 3 A cross-sectional view of the battery pack along line AA;

[0041] Figure 5 for Figure 4 Enlarged view of section C of the battery pack;

[0042] Figure 6 for Figure 3 A cross-sectional view of the battery pack along line BB;

[0043] Figure 7 for Figure 6 Enlarged view of section D of the battery pack;

[0044] Figure 8 This is a perspective view of the liquid cooling plate according to an embodiment of the present invention;

[0045] Figure 9 This is a side view of the liquid cooling plate according to an embodiment of the present invention;

[0046] Figure 10 for Figure 9 A cross-sectional view of the liquid cooling plate along line EE;

[0047] Figure 11 for Figure 10 Enlarged view of section F of the liquid cooling plate;

[0048] Figure 12 for Figure 10 An enlarged view of section G of the liquid cooling plate;

[0049] Figure 13 This is a cross-sectional view of the upper box cover according to an embodiment of the present invention;

[0050] Figure 14 This is a schematic diagram of the mesh structure according to an embodiment of the present invention;

[0051] Figure 15 This is a schematic diagram of an energy storage device according to an embodiment of the present invention;

[0052] Figure 16 for Figure 15 An enlarged view of section H of the energy storage device.

[0053] Explanation of reference numerals in the attached figures:

[0054] Battery pack-100, casing-12, battery cell-14, top cover-16, liquid cooling plate-18, mesh structure-19, receiving cavity-20, gap-21, opening-22, strip-23, side plate-24, sealing edge-26, connection part-28, sealing groove-30, sealing ring-32, first fixing hole-34, second fixing hole-36, sealing plate-38, flow channel plate-40, protective plate-42, first groove-44, second groove-45, first flow channel-46, second flow channel-47, first connector-48, second connector-50, liquid cooling unit-51, receiving tank-52, high voltage connector-54, mounting plate-56, bracket-57, energy storage device-200. Detailed Implementation

[0055] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0056] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0057] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. They can refer to a mechanical connection or an electrical connection. They can refer to a direct connection or an indirect connection through an intermediate medium, and they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0058] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0059] The following disclosure provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0060] Please refer to Figures 1 to 4 The battery pack 100 provided in this embodiment of the invention includes a housing 12 and battery cells 14. The housing 12 includes an upper cover 16 and a liquid cooling plate 18. The upper cover 16 has a receiving cavity 20, and the bottom of the upper cover 16 has an opening 22 communicating with the receiving cavity 20. The liquid cooling plate 18 is sealed to the bottom of the upper cover 16 and closes the opening 22. The upper cover 16 is an insulating component. The battery cells 14 are located in the receiving cavity 20 and supported by the liquid cooling plate 18. The battery cells 14 are thermally connected to the liquid cooling plate 18.

[0061] In the aforementioned battery pack 100, the battery cell 14 is housed in the receiving cavity 20 of the upper cover 16 and supported by the liquid cooling plate 18. The upper cover 16 is an insulating component to prevent the battery cell 14 from undergoing high-voltage breakdown and high-voltage arcing during thermal runaway. It can also reduce the cost and weight of the casing 12, thereby reducing the weight of the battery pack 100, increasing the energy density of the battery pack 100, and reducing the overall cost.

[0062] Specifically, in this embodiment of the invention, the interior of the upper cover 16 is deepened to form a receiving cavity 20, and the liquid cooling plate 18 supports the battery cell 14. The upper cover 16 and the liquid cooling plate 18 are directly and sealed together, which eliminates the traditional side beams of the box body. At the same time, the upper cover 16 is an insulating component, which greatly reduces the cost and weight of the box body 12, reduces the weight of the battery pack 100, increases the energy density of the battery pack 100, and also reduces the overall cost.

[0063] Furthermore, since the upper cover 16 is an insulating component, there are no conductive components at the contact points with the battery cells 14. This prevents high-voltage arcing between the high-voltage circuit and the casing 12 when the battery cells 14 experience thermal runaway, which could cause the casing 12 to melt and allow oxygen to enter, exacerbating the thermal runaway within the battery pack 100. Simultaneously, it also prevents short circuits in other battery cells 14 within the battery pack 100 caused by high-voltage arcing, thus avoiding heat diffusion and potentially leading to a fire or explosion of the entire system. In one embodiment, the insulating component can be a non-metallic component.

[0064] The battery pack 100 may include one or more battery cells 14, and multiple battery cells 14 may form one or more battery modules. The multiple battery cells 14 may be electrically connected in series, parallel, or series-parallel configurations. This invention does not specifically limit the number, shape, or electrical connection form of the battery cells 14. Figure 2 In this device, there are two battery cells 14. The battery cells 14 are square in shape and connected in series. The two battery cells 14 are arranged in the left-right direction.

[0065] The battery cell 14 is supported on the liquid cooling plate 18. The liquid cooling plate 18 is sealed to the upper cover 16 so that the receiving cavity 20 forms a relatively sealed space, ensuring the moisture-proof and dust-proof performance of the battery pack 100.

[0066] In some embodiments, the material of the insulating element is selected from at least one of polypropylene, polycarbonate, polyphenylene ether, composites of polycarbonate and glass fiber, acrylonitrile-butadiene-styrene plastic (ABS), composites of acrylonitrile-butadiene-styrene plastic and glass fiber, composites of polyphenylene ether and glass fiber, and composites of epoxy resin and glass fiber.

[0067] In this way, the material of the upper cover 16 can be flexibly selected.

[0068] Specifically, in one embodiment, the material of the insulating element may be selected from polypropylene (PP), polycarbonate (PC), polyphenylene ether (PPO), a composite of polycarbonate and glass fiber, acrylonitrile-butadiene-styrene (ABS), a composite of acrylonitrile-butadiene-styrene and glass fiber, a composite of polyphenylene ether and glass fiber, or a composite of epoxy resin and glass fiber.

[0069] In one embodiment, the material of the insulating element may be selected from two or more of the following: polypropylene, polycarbonate, polyphenylene ether, a composite of polycarbonate and glass fiber, acrylonitrile-butadiene-styrene plastic, a composite of acrylonitrile-butadiene-styrene plastic and glass fiber, a composite of polyphenylene ether and glass fiber, or a composite of epoxy resin and glass fiber.

[0070] In some implementations, please refer to Figures 13 to 14 The upper cover 16 includes multiple mesh structures 19 and filler (not shown). The multiple mesh structures 19 are stacked, and the filler fills the gaps 21 of the mesh structures 19 and connects the multiple mesh structures 19.

[0071] In this way, the structural strength of the upper box 12 can be guaranteed.

[0072] Specifically, the filler fills the gaps 21 of the grid structure 19. On the one hand, the filler can connect multiple grid structures 19 together. On the other hand, the filler filling the gaps 21 can reduce the voids inside the upper cover 16 and ensure the structural strength of the upper cover 16.

[0073] In one embodiment, the mesh structure 19 may be formed by arranging multiple strips 23 (such as glass fibers) in a crisscross pattern, and the filler may include a mixture of epoxy resin and adhesive materials. It is understood that in other embodiments, the mesh structure 19 may also be formed by other strips 23 (such as carbon nanotubes), and the filler is not limited to a mixture of epoxy resin and adhesive materials, as long as it is a suitable material for filling the gaps 21 of the mesh structure 19.

[0074] In some implementations, please refer to Figures 3 to 7 The upper cover 16 includes a side plate 24, and the bottom of the side plate 24 is provided with a sealing edge 26, which is sealed to the liquid cooling plate 18. The sealing edge 26 and the side plate 24 are connected to form a connecting part 28, which is configured to rupture and form a gap channel when the air pressure in the receiving cavity 20 exceeds the air pressure threshold. The receiving cavity 20 is connected to the outside of the box 12 through the gap channel.

[0075] This can improve the safety of the battery pack 100 in the event of thermal runaway in the battery cell 14.

[0076] Specifically, when a battery cell 14 inside the battery pack 100 experiences thermal runaway, the explosion-proof valve of the battery cell 14 will burst open, and the high-pressure gas of the battery cell 14 will be released into the containment cavity 20. As a result, the gas pressure inside the housing 12 will accumulate and increase. When the gas pressure inside the containment cavity 20 exceeds the gas pressure threshold, the connection part 28 will rupture to form a gap channel. The high-temperature electrolyte sprayed from the explosion-proof valve of the failed battery cell 14 will flow onto the liquid cooling plate 18 and then flow out of the battery pack 100 through the gap channel. This prevents the electrolyte from accumulating inside the battery pack 100 and being ignited by sparks, thereby improving the safety of the battery pack 100 when the battery cell 14 experiences thermal runaway.

[0077] The air pressure threshold can be set according to the design requirements. The connection part 28 is designed according to the air pressure threshold so that when the air pressure in the receiving cavity 20 exceeds the air pressure threshold, the connection part 28 will break to form a gap channel.

[0078] In some implementations, please refer to Figure 7 The connecting part 28 has a rounded corner structure.

[0079] In this way, the connection part 28 can be easily broken when the battery cell 14 experiences thermal runaway.

[0080] Specifically, the inner wall of the connecting part 28 is the side wall of the receiving cavity 20. The connecting part 28 has a rounded corner structure and an arc-shaped inner wall. The arc-shaped inner wall is subjected to the air pressure in the receiving cavity 20 along its surface. The pressure direction is towards the center of the rounded corner structure, which easily forms stress concentration inside the connecting part 28, making the connecting part 28 prone to breakage when the battery cell 14 experiences thermal runaway.

[0081] In one example, the rounded corner structure can be an R2 or R5 rounded corner structure.

[0082] In some implementations, please refer to Figure 7 The upper cover 16 includes a side plate 24, and a sealing edge 26 is provided at the bottom of the side plate 24. The liquid cooling plate 18 forms an annular sealing groove 30, and a sealing ring 32 is placed in the sealing groove 30. The sealing edge 26 is connected to the liquid cooling plate 18 and compresses the sealing ring 32. The sealing ring 32 seals and connects the sealing edge 26 and the liquid cooling plate 18.

[0083] In this way, the connection and sealing between the upper cover 16 and the liquid cooling plate 18 can be guaranteed.

[0084] Specifically, along the circumference of the upper cover 16, the sealing edge 26 extends outward perpendicularly to the side plate 24. An annular sealing groove 30 is formed on the upper surface of the liquid cooling plate 18. In the height direction of the battery pack 100, the sealing edge 26 covers the sealing groove 30 and presses against the sealing ring 32, so that the sealing ring 32 seals the connection between the sealing edge 26 and the liquid cooling plate 18. The sealing groove 30 also limits the position of the sealing ring 32, preventing it from shifting and affecting the sealing effect. Figures 1 to 3 In the middle, the height direction of the battery pack 100 can be vertical.

[0085] In one example, the sealing ring 32 can be a rubber ring.

[0086] Please refer to the relevant documents when entering a new location. Figure 2 , Figure 7 and Figure 8 Along the circumference of the upper cover 16, the sealing edge 26 has multiple first fixing holes 34, and the liquid cooling plate 18 has multiple second fixing holes 36. The first fixing holes 34 and the second fixing holes 36 are connected in a one-to-one correspondence. The battery pack 100 also includes multiple fasteners (such as bolts), each fastener passing through one first fixing hole 34 and one second fixing hole 36 and fixingly connecting the upper cover 16 and the liquid cooling plate 18. The sealing ring 32 is compressed to achieve a seal on the battery pack 100.

[0087] In some implementations, please refer to Figure 7 Battery pack 100 satisfies the following relationship:

[0088] c = k * b, where k is the compressible range of the sealing ring 32, and the value of k is [0.2, 0.4], c is the depth of the sealing groove 30, and b is the width of the sealing ring 32.

[0089] In this way, the sealing effect of the sealing ring 32 can be guaranteed.

[0090] Specifically, if the width of the sealing ring 32 is too large, although it can achieve a sealing effect, the sealing ring 32 will creep under excessive compression and prolonged compression time, which means that the sealing elasticity performance of the sealing ring 32 will become worse and worse. Therefore, when designing the seal, it is necessary to comprehensively consider the depth of the sealing groove 30 and the width of the sealing ring 32.

[0091] If k is less than 0.2, the depth of the sealing groove 30 is small, causing the width of the sealing ring 32 to far exceed the depth of the sealing groove 30. In this case, when the sealing ring 32 is compressed, part of the sealing ring 32 will extend beyond the sealing groove 30. Although the sealing ring 32 will have a good sealing effect in the short term, it will undergo creep deformation, which is not conducive to long-term use.

[0092] If k is greater than 0.4, then when the sealing ring 32 is compressed, the depth of the sealing groove 30 will exceed the width of the sealing ring 32 when the sealing performance is optimal, and the sealing effect will be worse. Therefore, the optimal choice is a value range of [0.2, 0.4] for k, so that the sealing ring 32 is not easily crushed and reliable sealing performance can be guaranteed.

[0093] The value of k ranges from [0.2, 0.4], that is, 0.2 ≤ k ≤ 0.4. In one example, k can be 0.2, 0.25, 0.3, 0.35, 0.4, or other values ​​between 0.2 and 0.4.

[0094] In some implementations, please refer to Figure 7 Battery pack 100 satisfies the following relationship:

[0095] a = k * d + b, where k is the compressible range of the sealing ring 32, and the value range of k is [0.2, 0.4], a is the width of the sealing groove 30, b is the width of the sealing ring 32, and d is the height of the sealing ring 32.

[0096] In this way, the sealing effect of the sealing ring 32 can be guaranteed.

[0097] Specifically, if k is less than 0.2, the width of the sealing groove 30 is smaller, and the sealing ring 32 expands more horizontally after being compressed. This horizontally expanded part is easily wrinkled and squeezed, leading to failure.

[0098] If k is greater than 0.4, the width of the sealing groove 30 will be larger. When the sealing ring 32 is under compression, the width of the sealing groove 30 will exceed the width of the sealing ring 32 at its optimal sealing performance value, and the sealing effect will be worse.

[0099] Therefore, the optimal choice for k is a range of [0.2, 0.4], which ensures that the sealing ring 32 is not easily damaged and can guarantee reliable sealing.

[0100] The value of k ranges from [0.2, 0.4], that is, 0.2 ≤ k ≤ 0.4. In one example, k can be 0.2, 0.25, 0.3, 0.35, 0.4, or other values ​​between 0.2 and 0.4.

[0101] In some implementations, please refer to Figures 9 to 12The liquid cooling plate 18 includes a sealing plate 38, a flow channel plate 40, and a protective plate 42 stacked sequentially from top to bottom. The sealing plate 38 is sealed to the bottom of the upper cover 16. The flow channel plate 40 includes a first side 39 and a second side 41 facing away from each other. The first side 39 is provided with a first groove 44. The sealing plate 38 covers the first groove 44 to form a first flow channel 46. The second side 41 is provided with a second groove 45. The protective plate 42 covers the second groove 45 to form a second flow channel 47. The sealing plate 38 is provided with a first connector 48 and a second connector 50. The first connector 48 and the second connector 50 are respectively connected to the two ends of the first flow channel 46 and the two ends of the second flow channel 47.

[0102] In this way, a liquid cooling structure for the battery cell 14 can be formed.

[0103] Specifically, in one embodiment, the sealing plate 38, the flow channel plate 40, and the protective plate 42 can be connected by welding (such as brazing) to ensure the connection strength of the three and the sealing performance of the first flow channel 46 and the second flow channel 47. It is understood that in other embodiments, the sealing plate 38, the flow channel plate 40, and the protective plate 42 can be connected in other ways, not limited to welding. This invention does not specifically limit the materials of the sealing plate 38, the flow channel plate 40, and the protective plate 42. In one embodiment, the sealing plate 38, the flow channel plate 40, and the protective plate 42 can be formed by stamping aluminum alloy and then connected together. When the battery pack 100 is too large and requires high load-bearing strength, the liquid cooling plate 18 can be made of a high-strength profile welded together. The sealing groove 30 is provided on the upper surface of the sealing plate 38.

[0104] The protective plate 42 can protect the flow channel plate 40 from the outside of the battery pack 100, preventing the flow channel plate 40 from being damaged by impact and leaking liquid.

[0105] exist Figure 12 In the first groove 44, the opening faces upward, and the sealing plate 38 covers the first groove 44 and seals the opening of the first groove 44, so that the sealing plate 38 and the flow channel plate 40 surround the first groove 44 to form a first flow channel 46. The first flow channel 46 can be a flow channel with a meandering shape, or it can include multiple sub-flow channels arranged in parallel, without specific limitations here.

[0106] exist Figure 12 In the middle, the opening of the second groove 45 faces downward, and the protective plate 42 covers the second groove 45 and seals the opening of the second groove 45, so that the protective plate 42 and the flow channel plate 40 surround the second groove 45 to form a second flow channel 47. The second flow channel 47 can be a flow channel with a meandering shape, or it can include multiple sub-flow channels arranged in parallel, without specific limitations here.

[0107] The first connector 48 and the second connector 50 are respectively connected to the two ends of the first flow channel 46, and the first connector 48 and the second connector 50 are respectively connected to the two ends of the second flow channel 47. Optionally, the first connector 48 can be used as an inlet connector, and the second connector 50 can be used as an outlet connector. The liquid cooling unit 51 can be connected to the first connector 48 and the second connector 50 through a pipe. When cooling the battery pack 100, the liquid cooling unit 51 can input the cryogenic fluid from the first connector 48 into the first flow channel 46 and the second flow channel 47. The cryogenic fluid exchanges heat with the battery cell 14 through the sealing plate 38, cooling the battery cell 14. The temperature of the fluid rises after absorbing heat, and it flows out of the first flow channel 46 and the second flow channel 47 from the second connector 50 and enters the liquid cooling unit 51. The liquid cooling unit 51 cools the fluid to form cryogenic fluid, and the cryogenic fluid is input into the first flow channel 46 and the second flow channel 47 again through the first connector 48, and so on.

[0108] In one embodiment, the first surface 39 is provided with a first groove 44, and the sealing plate 38 covers the first groove 44 to form a first flow channel 46. The first connector 48 and the second connector 50 are respectively connected to the two ends of the first flow channel 46.

[0109] In one embodiment, the second surface 41 is provided with a second groove 45, and the protective plate 42 covers the second groove 45 to form a second flow channel 47. The sealing plate 38 is provided with a first connector 48 and a second connector 50, and the first connector 48 and the second connector 50 are respectively connected to the two ends of the second flow channel 47.

[0110] In some embodiments, the liquid cooling plate 18 is thermally connected to the bottom surface of the battery cell 14 by thermally conductive adhesive (not shown).

[0111] This can improve the heat dissipation efficiency of the battery cell 14.

[0112] Specifically, the thermally conductive adhesive can adhere to the bottom surfaces of the liquid cooling plate 18 and the battery cell 14, reducing the gap between the liquid cooling plate 18 and the battery cell 14, thereby increasing the heat transfer path and improving the heat dissipation efficiency of the battery cell 14. In one example, the thermally conductive adhesive can be silicone.

[0113] In some implementations, please refer to Figure 8 A receiving groove 52 is formed on the upper surface of the liquid cooling plate 18, and the thermally conductive adhesive is contained in the receiving groove 52.

[0114] This prevents the thermal adhesive from overflowing.

[0115] Specifically, to ensure the thermal conductivity of the thermally conductive adhesive, it is typically required to cover the bottom surface of all battery cells 14. Therefore, a considerable amount of thermally conductive adhesive is usually applied to the liquid cooling plate 18. Since the thermally conductive adhesive has a certain degree of fluidity, using the receiving groove 52 on the liquid cooling plate 18 to hold the adhesive allows for a larger amount of adhesive on the liquid cooling plate 18, ensuring efficient heat dissipation. Furthermore, it prevents the adhesive from overflowing from the liquid cooling plate 18, maintaining the cleanliness of the battery pack 100.

[0116] exist Figure 1 In the upper cover 16, a high-voltage connector 54 is provided on the front side. The high-voltage connector 54 can connect to the electrodes of a battery pack formed by the electrical connection of multiple battery cells 14. The battery cells 14 can supply power to the outside world and be charged through the high-voltage connector 54. The high-voltage connector 54 is fixed to the front side of the upper cover 16 by a mounting plate 56.

[0117] In summary, the battery pack 100 according to the embodiments of the present invention has at least the following effects:

[0118] 1. The side beams of the traditional box can be eliminated, and the liquid cooling plate 18 can be used to support the battery cell 14. The upper box cover 16 can be made deeper and the upper box cover 16 can be directly sealed to the liquid cooling plate 18. The cost and weight of the box 12 are greatly reduced, the weight of the battery pack 100 is reduced, the energy density of the battery pack 100 is increased, and the overall cost is also reduced.

[0119] 2. There are no metal parts in contact with the battery cell 14. The upper cover 16 of the insulating part prevents high-voltage arcing between the high-voltage circuit and the metal casing when the battery cell 14 experiences thermal runaway. This prevents the casing from melting and breaking through, allowing oxygen to enter and exacerbating the thermal runaway inside the battery pack 100. At the same time, it also prevents short circuits in other battery cells 14 inside the battery pack 100 caused by high-voltage arcing, which could induce heat spread and cause the entire system to catch fire and explode.

[0120] 3. The upper cover 16 is an insulating component and has no side beams. The liquid cooling plate 18 does not have a receiving cavity 20. Furthermore, the connection between the sealing edge 26 and the side wall of the upper cover 16 is designed to rupture and form a gap channel when the gas pressure inside the receiving cavity 20 exceeds a pressure threshold. The receiving cavity 20 connects to the outside of the casing 12 through this gap channel. When thermal runaway occurs inside the battery pack 100, the gas pressure inside the battery pack 100 increases, causing the connection to crack and form a gap channel. The high-temperature electrolyte ejected from the explosion-proof valve of the failed battery cell 14 flows onto the liquid cooling plate 18 and then flows out of the battery pack 100 through the gap channel. This prevents the electrolyte from accumulating inside the battery pack 100 and igniting due to sparking.

[0121] Please refer to Figure 15 and Figure 16 An energy storage device 200 according to an embodiment of the present invention includes a battery pack 100 according to any of the above embodiments.

[0122] In the aforementioned energy storage device 200, the battery cell 14 is housed in the receiving cavity 20 of the upper cover 16 and supported by the liquid cooling plate 18. The upper cover 16 is an insulating component to prevent the battery cell 14 from experiencing high-voltage breakdown and high-voltage arcing during thermal runaway. It can also reduce the cost and weight of the housing 12, reduce the weight of the battery pack 100, increase the energy density of the battery pack 100, and reduce the overall cost.

[0123] Specifically, the energy storage device 200 may also include a support 57 on which one or more battery packs 100 can be mounted. Multiple battery packs 100 can be arranged in multiple battery pack layers on the support 57. The multiple battery packs 100 can be electrically connected in series, parallel, or series-parallel configurations.

[0124] Energy storage equipment 200 may include, but is not limited to, energy storage containers, household energy storage cabinets, and other energy storage equipment.

[0125] The energy storage device 200 also includes a liquid cooling unit 51, which is connected to the first connector 48 and the second connector 50 of the battery pack 100 via pipes.

[0126] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0127] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery pack, characterized in that, include: The enclosure includes an upper cover and a liquid cooling plate. The upper cover has a receiving cavity inside, and the bottom of the upper cover has an opening communicating with the receiving cavity. The liquid cooling plate is sealed to the bottom of the upper cover and closes the opening. The upper cover is an insulating component. A battery cell, wherein the battery cell is located within the receiving cavity and is supported by the liquid cooling plate, and the battery cell is thermally connected to the liquid cooling plate; The upper cover includes a side panel, and the bottom of the side panel is provided with a sealing edge, which is sealed to the liquid cooling plate. The sealing edge is connected to the side plate to form a connecting part. The connecting part is configured to rupture and form a gap channel when the air pressure in the receiving cavity exceeds the air pressure threshold. The receiving cavity is connected to the outside of the box through the gap channel. The connecting part has a rounded corner structure.

2. The battery pack according to claim 1, characterized in that, The material of the insulating component is selected from at least one of polypropylene, polycarbonate, polyphenylene ether, composites of polycarbonate and glass fiber, acrylonitrile-butadiene-styrene plastic, composites of acrylonitrile-butadiene-styrene plastic and glass fiber, composites of polyphenylene ether and glass fiber, and composites of epoxy resin and glass fiber.

3. The battery pack according to claim 1, characterized in that, The upper cover includes multiple mesh structures and filler, the multiple mesh structures are stacked, and the filler fills the gaps in the mesh structures and connects the multiple mesh structures.

4. The battery pack according to claim 1, characterized in that, The upper box cover includes a side panel, and the bottom of the side panel is provided with a sealing edge; The liquid cooling plate has an annular sealing groove, and a sealing ring is placed inside the sealing groove. The sealing edge is connected to the liquid cooling plate, and the sealing ring seals the sealing edge to the liquid cooling plate.

5. The battery pack according to claim 4, characterized in that, The battery pack satisfies the following relationship: c=k b, where k is the compressible range of the sealing ring, and the value of k ranges from [0.2, 0.4], c is the depth of the sealing groove, and b is the width of the sealing ring.

6. The battery pack according to claim 4 or 5, characterized in that, The battery pack satisfies the following relationship: a=k d+b, where k is the compressible range of the sealing ring, and the value of k ranges from [0.2, 0.4], a is the width of the sealing groove, b is the width of the sealing ring, and d is the height of the sealing ring.

7. The battery pack according to claim 1, characterized in that, The liquid cooling plate includes a sealing plate, a flow channel plate, and a protective plate stacked sequentially from top to bottom. The sealing plate is sealed to the bottom of the upper cover. The flow channel plate includes a first side and a second side facing away from each other. The first side is provided with a first groove, and the sealing plate covers the first groove to form a first flow channel, and / or; the second side is provided with a second groove, and the protective plate covers the second groove to form a second flow channel. The sealing plate is provided with a first connector and a second connector, which are respectively connected to the two ends of the first flow channel and / or respectively connected to the two ends of the second flow channel.

8. The battery pack according to claim 1, characterized in that, The liquid cooling plate is thermally connected to the bottom surface of the battery cell via thermally conductive adhesive.

9. The battery pack according to claim 8, characterized in that, The upper surface of the liquid cooling plate has a receiving groove, and the thermally conductive adhesive is contained in the receiving groove.

10. An energy storage device, characterized in that, Includes the battery pack as described in any one of claims 1-9.

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