Gasket, battery module and battery pack

Abstract

The invention provides a gasket, a battery module and a battery. The battery module comprises a plurality of single batteries and a plurality of gaskets, the gaskets are arranged between any two adjacent single batteries, and the gaskets can be in contact with the surfaces of the single batteries after being heated and melted. The invention aims to provide the battery module capable of preventing thermal runaway and thermal diffusion.

Description

Technical Field

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

[0002] For a battery pack, the phenomenon of uncontrollable temperature rise caused by the exothermic reaction inside the single cell in the battery module is called thermal runaway. When the heat generated by the battery module is higher than the heat it can dissipate, thermal runaway will occur. When a single cell in the battery pack has a problem, the thermal runaway of one single cell will cause thermal runaway of other cells, which is called thermal runaway diffusion, or simply thermal diffusion. In related technologies, a cooling device is often set in the battery pack to cool the battery module in the battery pack to avoid excessive temperature, but the problem of thermal diffusion cannot be solved. Summary of the invention

[0003] The embodiments of the present invention provide a gasket, a battery module and a battery pack, aiming to provide a battery module capable of preventing thermal runaway and heat diffusion.

[0004] In a first aspect, an embodiment of the present invention provides a battery module, comprising:

[0005] a plurality of single cells; and,

[0006] A plurality of gaskets are arranged between any two adjacent single cells, and the gaskets are arranged to contact the surface of the single cells after being melted by heat.

[0007] In one embodiment, the gasket includes a core material layer and a packaging layer, wherein the packaging layer is wrapped around the outside of the core material layer, the packaging layer is in contact with the surface of the single battery, and the packaging layer is at least partially melted by heat so that the core material layer wraps around the surface of the single battery.

[0008] In one embodiment, at a first temperature, the core material layer is fluid, at a second temperature, at least a portion of the encapsulation layer is melted, and at a third temperature, the core material layer is solidified, wherein the first temperature is lower than the second temperature, and the second temperature is lower than the third temperature.

[0009] In one embodiment, the first temperature is T1, the second temperature is T2, the third temperature is T3, T1<60°C, 60≤T2, T3≥100°C.

[0010] In one embodiment, the encapsulation layer includes a first side portion and a second side portion which are adjacent to each other, the first side portion is in contact with the surface of the single battery cell, and the melting point of the first side portion is higher than the melting point of the second side portion.

[0011] In one embodiment, the softening temperature of the first side portion is T4, 400°C≤T4≤1000°C.

[0012] In one embodiment, the thickness of the core material layer is H1, the thickness of the first side portion is H2, H2 / H1=(0.05-0.1):1; and / or,

[0013] The thickness of the core material layer is H1, the thickness of the second side portion is H3, and H3 / H1=(0.05-0.1):1.

[0014] In one embodiment, the core material layer comprises resin;

[0015] The first side portion comprises any one of fireproof cloth, nylon, and polyamide-imide;

[0016] The second side portion includes a polyethylene film.

[0017] In one embodiment, the thermal conductivity of the first side portion is lower than the thermal conductivity of the core material layer.

[0018] In one embodiment, two spacers are arranged between any two adjacent single cells;

[0019] The battery module further comprises a plurality of thermal insulation pads, wherein the thermal insulation pads are arranged between two of the gaskets.

[0020] In one embodiment, the thermal insulation pad includes any one of fireproof cloth, nylon, and polyamide-imide.

[0021] In a second aspect, an embodiment of the present invention provides a battery pack, comprising a plurality of battery modules as described above. The battery modules include:

[0022] a plurality of single cells; and,

[0023] A plurality of gaskets are arranged between any two adjacent single cells, and the gaskets are arranged to wrap around the surface of the single cells after being melted by heat.

[0024] In one embodiment, a cooling device is further included, and a plurality of the battery modules are connected to the cooling device. After the gasket is melted by heat, it is filled between the single battery and the cooling device.

[0025] In one embodiment, the cooling device includes a plurality of second cooling plates, and one second cooling plate is provided between two adjacent battery modules.

[0026] In one embodiment, the cooling device comprises a first cooling plate, and the plurality of battery modules are arranged on the first cooling plate. After the gasket is melted by heat, it fills the gap between the single battery and the first cooling plate.

[0027] In one embodiment, the cooling device further includes a plurality of second cooling plates, which are arranged on the first cooling plate, and one second cooling plate is arranged between two adjacent battery modules. After the gasket is melted by heat, it fills the gap between the single battery and the plurality of second cooling plates.

[0028] In one embodiment, the gasket melted by heat is connected between the single battery and the first cooling plate, and is also connected between the single battery and the plurality of second cooling plates.

[0029] In one embodiment, a plurality of temperature sensors are further included, each of the temperature sensors being disposed on each of the single cells to monitor the temperature of the corresponding single cell.

[0030] In a third aspect, an embodiment of the present invention provides a gasket for a battery module, wherein the gasket is the gasket in the battery module as described above.

[0031] Beneficial effects of the embodiments of the present invention:

[0032] In the technical solution of the present invention, when the battery module is working normally, the gasket is arranged between any two adjacent single cells to insulate the single cells and prevent the heat of the two adjacent single cells from being transferred to each other, resulting in an increase in temperature, thereby avoiding thermal runaway; when the temperature of the battery module rises, the gasket will melt due to the heat, and the melted gasket will be wrapped around the surface of the single cell, so that the single cells are separated from each other to avoid the spread of thermal runaway. With such an arrangement, when a single cell has thermal runaway, the gasket adjacent to this single cell will melt due to the heat and be wrapped around the outer surface of this single cell, isolating it from other single cells, thereby preventing the thermal runaway from spreading to other single cells, thereby improving the safety of the battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments 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 these drawings without creative work.

[0034] Figure 1 is a structural schematic diagram of an embodiment of a battery module provided by the present invention;

[0035] Figure 2 yes Figure 1 A is an enlarged schematic diagram;

[0036] Figure 3 yes Figure 1Schematic diagram of the structure of the middle gasket, thermal insulation pad and single battery;

[0037] Figure 4 yes Figure 1 A cross-sectional view of the middle gasket;

[0038] Figure 5 is a structural schematic diagram of an embodiment of a battery pack provided by the present invention;

[0039] Figure 6 yes Figure 5 A schematic structural diagram of an embodiment of a cooling device;

[0040] Figure 7 yes Figure 6 A cross-sectional view of the second cooling plate;

[0041] Figure 8 yes Figure 7 A magnified schematic diagram of B.

[0042] Description of Figure Numbers

[0043] Label name Label name 1000 Battery Pack 21 First side 100 Battery Module 22 Second side a Single battery 20 Insulation pad 10 Gasket 200 Cooling device 1 Core layer 201 First cooling plate 2 Encapsulation layer 202 Second cooling plate c1 First side c2 Second side d Runner e1 Partition e2 First Board e3 Second board 300 Cabinet 400 BMS control system 500 Collection line DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. In the present invention, unless otherwise specified, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the drawings; while "inside" and "outside" refer to the outline of the device.

[0045] For a battery pack, the phenomenon of uncontrollable temperature rise caused by the exothermic reaction inside the single cell in the battery module is called thermal runaway. When the heat generated by the battery module is higher than the heat it can dissipate, thermal runaway will occur. When a single cell in the battery pack has a problem, the thermal runaway of one single cell will cause thermal runaway of other cells, which is called thermal runaway diffusion, or simply thermal diffusion. In related technologies, a cooling device is often set in the battery pack to cool the battery module in the battery pack to avoid excessive temperature, but the problem of thermal diffusion cannot be solved.

[0046] In view of this, the present invention proposes a battery module 100, Figures 1 to 4This is a structural schematic diagram of an embodiment of a battery module 100 provided by the present invention. The battery module 100 provided by the present invention has good heat dissipation, can prevent heat diffusion, and has higher safety. The battery module 100 will be described in detail below in conjunction with the main drawings.

[0047] See also Figure 1 and Figure 2 The battery module 100 includes a plurality of single cells a and a plurality of gaskets 10; the gasket 10 is arranged between any two adjacent single cells a, and the gasket 10 is arranged to wrap the surface of the single cell a after being melted by heat.

[0048] In the technical solution of the present invention, when the battery module 100 is working normally, the gasket 10 is arranged between any two adjacent single cells a to insulate the single cells a, so as to prevent the heat of the two adjacent single cells a from being transferred to each other, resulting in an increase in temperature, thereby avoiding thermal runaway; when the temperature of the battery module 100 rises, the gasket 10 will melt due to the heat, and the melted gasket 10 will be wrapped around the surface of the single cell a, so that the single cells a are separated from each other to avoid the spread of thermal runaway. With such an arrangement, when a single cell a has thermal runaway, the gasket 10 adjacent to the single cell a will melt due to the heat and be wrapped around the outer surface of the single cell a, separating it from other single cells a, thereby preventing the thermal runaway from spreading to other single cells a, thereby improving the safety of the battery module 100.

[0049] During the actual operation of the battery module 100, a problem may occur in a single cell a or multiple cells a. When a problem occurs in a single cell a in the battery module 100 and thermal runaway occurs, the temperature of the single cell a rises rapidly, and the gasket 10 adjacent to the single cell a is affected by the temperature and melts due to the heat. The melted gasket 10 wraps around the surface of the single cell a, thereby isolating the single cell a from other single cells a, and preventing the thermal runaway from spreading between the single cells a. When multiple cells a in the battery module 100 have thermal runaway, the temperature of the entire battery module 100 begins to rise, and multiple gaskets 10 are affected by the temperature and melt, and the melted gasket 10 wraps around the surface of multiple cells a, thereby isolating the multiple cells a from each other, thereby preventing the thermal runaway from spreading between the single cells a.

[0050] In this embodiment, the gasket 10 can realize the heat insulation function to prevent the heat between the single cells a from being transferred to each other, which would lead to aggravated thermal runaway. It can also play a buffering and protective role. When the battery module 100 is impacted, the gasket 10 can absorb part of the impact force, thereby preventing the single cell a from being squeezed and deformed.

[0051] It should be noted that the gasket 10 provided by the present invention has two states. When the battery module 100 is working normally, the gasket 10 is in the first state, arranged between two single cells a, and the gasket 10 is in contact with the surfaces of two adjacent single cells a. When the battery module 100 has thermal runaway, the gasket 10 is in the second state, that is, part of the gasket 10 is melted by heat, and the melted part of the gasket 10 is wrapped around the surface of the single cell a. In the first state, the gasket 10 is used to isolate the two adjacent single cells a to avoid heat transfer between the two adjacent single cells a, thereby avoiding excessive local temperature of the battery module 100. In the second state, the melted part of the gasket 10 is wrapped around the surface of the single cell a to avoid aggravation of thermal runaway.

[0052] See also Figure 3 and Figure 4 , the gasket 10 includes a core material layer 1 and a packaging layer 2, the packaging layer 2 is wrapped around the outside of the core material layer 1, and the packaging layer 2 is in contact with the surface of the single cell a; in this embodiment, the function of the packaging layer 2 is to insulate heat to prevent heat transfer between two adjacent single cells a, and the function of the core material layer 1 is to wrap around the surface of the single cell a. Specifically, when the battery module 100 is working normally, the core material layer 1 is wrapped in the packaging layer 2, and the functions of both at this time are to insulate heat to prevent heat transfer between two adjacent single cells a. When thermal runaway occurs in the battery module 100, the packaging layer 2 is at least partially affected by the temperature increase and begins to melt, causing the core material layer 1 in the packaging layer 2 to flow out, and the core material layer 1 after flowing out wraps the surface of the single cell a, thereby isolating the single cell a to prevent further aggravation of thermal runaway.

[0053] Further, in some embodiments, at the first temperature, the core material layer 1 is fluid, and at the first temperature, the core material layer 1 is wrapped in the encapsulation layer 2, so even if the core material layer 1 is fluid, it will not affect its function; at the second temperature, at least part of the encapsulation layer 2 melts, and at the second temperature, part of the encapsulation layer 2 melts, and the core material layer 1 in the encapsulation layer 2 flows out. Since the core material layer 1 is fluid, the outflowing core material layer 1 can cover the surface of the single battery a. At the third temperature, the core material layer 1 solidifies, and as the temperature of the battery module 100 increases, the core material layer 1 gradually begins to solidify until it is completely wrapped on the surface of the single battery a, thereby isolating the single battery a. It should be noted that the specific temperature ranges of the first temperature, the second temperature and the third temperature can be set according to the specific type of the single battery a. Different types of single batteries a have different temperatures for thermal runaway. Further, the first temperature is lower than the second temperature, and the second temperature is lower than the third temperature.

[0054] In this embodiment, the single cell a is mainly a lithium iron phosphate battery, therefore, the first temperature is T1, the second temperature is T2, the third temperature is T3, T1<60°C, 60≤T2, T3≥100°C. When the temperature of the battery module 100 is lower than 60°C, the core material layer 1 is fluid and is wrapped in the encapsulation layer 2. The core material layer 1 has a certain fluidity before being stimulated and solidified, so as to ensure that it can flow out of the encapsulation layer 2. When the temperature of the battery module 100 gradually rises and rises to above 60°C, part of the encapsulation layer 2 melts, and the core material layer 1 in the encapsulation layer 2 flows out and wraps around the surface of the single cell a. At this time, the temperature of the battery module 100 will continue to rise. When the temperature of the battery module 100 is greater than 100°C, the core material layer 1 wrapped on the surface of the single cell a begins to be fixed, thereby isolating multiple single cells a from each other.

[0055] See also Figure 4 The packaging layer 2 includes a first side portion 21 and a second side portion 22 adjacent to each other. The first side portion 21 is attached to the surface of the single cell a. In this embodiment, the first side portion 21 is used to attach to the surface of the single cell a. The main function is to insulate heat and prevent the temperature of the single cell a from being transferred to each other. When the temperature rises, the second side portion 22 needs to melt so that the core material layer 1 in the packaging layer 2 flows out. Therefore, in order to achieve the above functions, the melting point of the first side portion 21 needs to be greater than the melting point of the second side portion 22. At the same time, the softening temperature of the second side portion 22 needs to be lower than the excitation and curing temperature of the core material layer 1. If the softening temperature of the second side portion 22 is greater than the excitation and curing temperature of the core material layer 1, the core material layer 1 will solidify when it will flow out of the packaging layer 2, and the function of isolating the single cell a cannot be achieved.

[0056] It should be noted that the core material layer 1 has a certain fluidity before being stimulated and fixed, so that it can flow out of the packaging layer 2. In fact, the first side portion 21 and the second side portion 22 enclose a receiving cavity, and the core material layer 1 is encapsulated in the receiving cavity. During the packaging process, the core material layer 1 needs to completely fill the entire receiving cavity.

[0057] In some embodiments, the softening temperature of the first side portion 21 is greater than the softening temperature of the second side portion 22, and the softening temperature of the first side portion 21 is greater than the curing excitation temperature of the core material layer 1, and the softening temperature of the second side portion 22 is lower than the curing excitation temperature of the core material layer 1. Further, the softening temperature of the first side portion 21 is T4, 400°C≤T4≤1000°C. The softening temperature of the second side portion 22 is T5, 60°C≤T5≤80°C. The curing excitation temperature of the core material layer 1 is T6, T6≥100°C.

[0058] The specific working principle of the gasket 10 is as follows: when the temperature of the battery module 100 reaches 60°C to 80°C, the second side portion 22 begins to soften (the first side portion 21 remains unchanged), and the core material layer 1 in the encapsulation layer 2 flows out and covers the surface of the single battery a. As the temperature of the battery module 100 gradually increases, the softening degree of the second side portion 22 increases, gradually reaching a melting point above 100°C, the second side portion 22 melts, and the core material layer 1 begins to solidify and is fixed on the single battery a, separating multiple single battery a.

[0059] It should be noted that the principle for setting the ratio among the core material layer 1, the first side portion 21 and the second side portion 22 is: the width of the second side portion 22 is set according to the spacing between the single cells a, the width of the first side portion 21 is equal to the width of the single cell a, the packaging layer 2 needs to be filled with the core material layer 1 with an amount of space volume equal to the spacing between the single cells a, and the core material layer 1 is in a compressed state.

[0060] In some embodiments, the thickness of the core material layer 1 is H1, the thickness of the first side portion 21 is H2, and H2 / H1=(0.05-0.1): 1; it should be noted that when H2 / H1 is less than 0.05, the thickness of the first side portion 21 is too thin and is easily damaged during use, causing the core material layer 1 to flow out, affecting the normal operation of the battery module 100. When H2 / H1 is greater than 0.1, the thickness of the first side portion 21 is relatively thick, and the occupied space increases. More specifically, the thickness of the first side portion 21 is 0.05-0.1 mm, and H2 can be 0.05 mm, 0.052 mm, 0.055 mm, 0.058 mm, 0.06 mm, 0.061 mm, 0.065 mm, 0.069 mm, 0.07 mm, 0.072 mm, 0.075 mm, 0.078 mm, 0.08 mm, 0.085 mm, 0.086 mm, 0.087 mm, 0.088 mm, 0.09 mm, 0.091 mm, 0.092 mm, 0.093 mm, 0.098 mm, 0.099 mm, 0.1 mm or other data not listed.

[0061] The thickness of the core layer 1 is 0.6-1.4 mm. More specifically, H1 can be 0.6 mm, 0.62 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.88 mm, 0.89 mm, 0.9 mm, 0.91 mm, 0.92 mm, 0.95 mm, 0.99 mm, 1 mm, 1.1 mm, 1.15 mm, 1.18 mm, 1.2 mm, 1.22 mm, 1.25 mm, 1.29 mm, 1.3 mm, 1.33 mm, 1.35 mm, 1.36 mm, 1.38 mm, 1.4 mm or other unlisted data.

[0062] In some embodiments, the thickness of the core material layer 1 is H1, the thickness of the second side portion 22 is H3, and H3 / H1=(0.05-0.1): 1. It should be noted that when H3 / H1 is less than 0.05, the thickness of the second side portion 22 is too thin and is easily damaged during use, causing the core material layer 1 to flow out, affecting the normal operation of the battery module 100. When H3 / H1 is greater than 0.1, the thickness of the second side portion 22 is relatively thick, and the occupied space increases. More specifically, the thickness of the second side portion 22 is 0.05-0.1 mm, and H3 can be 0.05 mm, 0.052 mm, 0.055 mm, 0.058 mm, 0.06 mm, 0.061 mm, 0.065 mm, 0.069 mm, 0.07 mm, 0.072 mm, 0.075 mm, 0.078 mm, 0.08 mm, 0.085 mm, 0.086 mm, 0.087 mm, 0.088 mm, 0.09 mm, 0.091 mm, 0.092 mm, 0.093 mm, 0.098 mm, 0.099 mm, 0.1 mm or other data not listed.

[0063] In some embodiments, considering the issue of space utilization, the overall thickness of the gasket 10 is 0.8 to 1.5 mm. Specifically, the overall thickness of the gasket 10 can be 0.8 mm, 0.82 mm, 0.85 mm, 0.88 mm, 0.9 mm, 0.91 mm, 0.92 mm, 0.95 mm, 0.98 mm, 1 mm, 1.05 mm, 1.08 mm, 1.1 mm, 1.11 mm, 1.12 mm, 1.15 mm, 1.16 mm, 1.18 mm, 1.2 mm, 1.22 mm, 1.25 mm, 1.26 mm, 1.27 mm, 1.3 mm, 1.31 mm, 1.35 mm, 1.36 mm, 1.38 mm, 1.4 mm, 1.42 mm, 1.44 mm, 1.45 mm, 1.48 mm, 1.5 mm or other data not listed.

[0064] In some embodiments, the core material layer 1 includes a resin; the resin has weak viscosity and micro-flowability at a temperature below 70° C., and can flow out of the packaging layer 2 after the second side portion 22 melts; when the temperature reaches above 100° C., the resin gradually solidifies. More specifically, the resin can be an epoxy resin.

[0065] In some embodiments, the first side portion 21 includes any one of fireproof cloth, nylon, and polyamide-imide; the above material is resistant to high temperatures of 400°C to 1200°C, has low thermal conductivity, excellent high-temperature insulation performance, high tensile strength and long service life, and when thermal runaway occurs in the battery module 100, it can isolate the transfer of heat and avoid aggravation of thermal runaway.

[0066] In some embodiments, the second side portion 22 includes a polyethylene film. The polyethylene film has good chemical stability, and the polymer molecules in the material are connected by carbon-carbon single bonds, and can withstand the corrosion of most acids and alkalis (not resistant to oxidizing acids), and is insoluble in general solvents at room temperature, has low water absorption, and has excellent electrical insulation.

[0067] In this embodiment, in order to prevent thermal runaway from aggravating, the thermal conductivity of the first side portion 21 is lower than the thermal conductivity of the core material layer 1 .

[0068] See also Figure 3 In this embodiment, the battery module 100 further includes a plurality of heat insulating pads 20, and two gaskets 10 are arranged between any two adjacent single batteries a, and the heat insulating pad 20 is arranged between the two gaskets 10. Such an arrangement improves the safety of the battery module 100, and the heat insulation is provided by the gaskets 10 and the heat insulating pads 20 to avoid heat transfer between two adjacent single batteries a, thereby improving the safety of the battery module 100.

[0069] Furthermore, the thermal insulation pad 20 includes any one of fireproof cloth, nylon, and polyamide-imide. The above materials are resistant to high temperatures of 400°C to 1200°C, have low thermal conductivity, excellent high-temperature insulation performance, high tensile strength and long service life, and can isolate heat transfer when thermal runaway occurs in the battery module 100 to prevent thermal runaway from intensifying.

[0070] The present invention also provides a battery pack 1000, see Figures 5 to 8 The battery pack 1000 includes the battery module 100. The specific structure of the battery module 100 is referred to the above embodiment. Since the battery pack 1000 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0071] In some embodiments, see Figure 5 and Figure 6In order to prevent the battery pack 1000 from thermal runaway, a cooling device 200 is also provided in the battery pack 1000. Multiple battery modules 100 are connected to the cooling device 200. In the actual working process, the cooling device 200 is used to cool the battery module 100 to prevent the temperature of the battery module 100 from being too high. In this embodiment, the gasket 10 is provided between the single cells a of the battery module 100. When the battery pack 1000 is working normally, the gasket 10 is used to isolate the single cells a to prevent the temperature transfer between the single cells a, thereby preventing a single cell a from being too high in temperature and causing thermal runaway. When the temperature of the battery pack 1000 rises, the gasket 10 melts due to heat and fills the space between the single cell a and the cooling device 200. At this time, the gasket 10 acts as a bridge structure to connect the single cell a with the cooling device 200, and the temperature of the single cell a is quickly transferred to the cooling device 200 through the bridge structure, thereby achieving the purpose of rapid cooling and preventing the thermal runaway from being aggravated.

[0072] It should be noted that the specific type of the cooling device 200 is not limited, as long as it can cool the battery module 100 .

[0073] In some embodiments, the battery pack 1000 includes a box body 300, a accommodating cavity is formed in the box body 300, the cooling device 200 includes a first cooling plate 201, the first cooling plate 201 is arranged in the box body 300, and multiple battery modules 100 are located on the first cooling plate 201. A gap is formed between the bottom of the multiple battery modules 100 and the first cooling plate 201. When the temperature of the battery pack 1000 rises, the gasket 10 is heated and melted, and fills the gap between the single battery a and the first cooling plate 201.

[0074] For further information, see Figure 6 In order to improve cooling efficiency, the cooling device 200 further includes a plurality of second cooling plates 202, and a second cooling plate 202 is provided between two adjacent battery modules 100. It should be noted that the first cooling plate 201 and the plurality of second cooling plates 202 can be provided one by one or both at the same time, and the selection can be made according to the actual situation.

[0075] In some embodiments, the cooling device 200 is only provided with a first cooling plate 201 , and the plurality of battery modules 100 are located on the first cooling plate 201 and are cooled by the first cooling plate.

[0076] In some other embodiments, the cooling device 200 is only provided with a plurality of second cooling plates 202 , a second cooling plate 202 is provided between two adjacent battery modules 100 , and cooling is performed through the plurality of second cooling plates 202 .

[0077] In some embodiments, the cooling device 200 includes a first cooling plate 201 and a plurality of second cooling plates 202. Specifically, the plurality of second cooling plates 202 are disposed on the first cooling plate 201, the plurality of battery modules 100 are located on the first cooling plate 201, and a second cooling plate 202 is disposed between two adjacent battery modules 100. After the gasket 10 is heated and melted, it fills the gap between the single battery a and the plurality of second cooling plates 202.

[0078] It should be noted that, in order to improve the cooling efficiency, the gasket 10 after being melted by heat connects the multiple single cells a to the first cooling plate 201. At this time, the gasket 10 acts as a "bridge" and can quickly transfer the temperature of the single cell a to the first cooling plate 201, thereby improving the cooling efficiency. Similarly, the gasket 10 after being melted by heat connects the multiple single cells a to the multiple second cooling plates 202. At this time, the gasket 10 acts as a "bridge" and can quickly transfer the temperature of the single cell a to the second cooling plate 202, thereby improving the cooling efficiency.

[0079] It should be noted that, in order to improve the thermal conductivity of the core material layer 1 , an inducing agent is often doped into the core material layer 1 .

[0080] In some embodiments, the core material layer 1 is epoxy resin, and fillers with thermal conductivity such as aluminum or copper particles are mixed and added to the epoxy resin to improve the thermal conductivity of the epoxy resin, so that the epoxy resin can quickly transfer the heat of the single cell a to the first cooling plate 201 or the second cooling plate 202. The specific ratio and mixing preparation method of the epoxy resin and the filler can refer to the conventional settings in the field, and will not be repeated here.

[0081] In some other embodiments, the core material layer 1 is epoxy resin, and the composition ratio of the epoxy resin is adjusted, for example, the cross-linking degree of the epoxy resin is increased, the distance between the molecular structures of the epoxy resin is reduced, and the heat transfer efficiency is improved, thereby improving the thermal conductivity of the epoxy resin, so that the epoxy resin can quickly transfer the heat of the single cell a to the first cooling plate 201 or the second cooling plate 202. The adjustment method of the composition ratio of the epoxy resin can refer to the conventional settings in the field, and will not be repeated here.

[0082] In some other embodiments, the core material layer 1 is epoxy resin, and a heat conduction aid is added to the epoxy resin, such as graphite, carbon fiber and other compounds with high thermal conductivity, to improve the heat transfer efficiency, thereby improving the thermal conductivity of the epoxy resin, so that the epoxy resin can quickly transfer the heat of the single cell a to the first cooling plate 201 or the second cooling plate 202. The specific operation method can refer to the conventional settings in the field, and will not be repeated here.

[0083] It should be noted that by adding other compounds to the core material layer 1 to improve the chemical properties of the core material layer 1, the cured core material layer 1 becomes soft and rubbery with excellent impact resistance; most importantly, the cured core material layer 1 has high thermal conductivity and electrical insulation. Specifically, the principle of thermal curing is that when the material is heated at high temperature, the curing agent therein undergoes thermal decomposition or thermal activation, releases activation energy, and then initiates a curing reaction.

[0084] The specific working principle of the battery pack 1000 provided in this embodiment is as follows: when the battery pack 1000 has thermal runaway, the core material layer 1 flows out and fills the gap between the single battery a and the first cooling plate 201, and also fills the gap between the single battery a and the second cooling plate 202. The initiator that expands under the influence of temperature and increases the pressure inside the thermal conductive adhesive is mixed inside the flowable core material layer 1. When the battery pack 1000 is in the high temperature initiation stage, that is, the temperature inside the battery pack 1000 reaches 60°C to 100°C, the expansion initiator starts to work, the internal pressure of the core material layer 1 is greater than the internal pressure of the battery pack 1000, and the flowable core material layer 1, from the softened packaging The core material layer 1 is sprayed out from the first cooling plate 201 and the single battery a to form an overlap, and the second cooling plate 202 is in contact with the single battery a to form an overlap; the temperature in the battery pack 1000 continues to rise, and the temperature exceeds 100°C (the thermal runaway development stage of the battery pack 1000). At this time, the core material layer 1 is gradually solidified. When the thermal runaway of the battery pack 1000 breaks out, the core material layer 1 forms a stable heat conduction-cooling overlap with the first cooling plate 201 and the second cooling plate 202. The temperature of the single battery a is transferred to the first cooling plate 201 and the second cooling plate 202 through the overlapping core material layer 1, and the heat in the battery pack 1000 is diffused in large quantities to avoid heat diffusion and fire.

[0085] In some embodiments, see 7 and Figure 8 ,by Figure 7 Taking the first direction in the figure as an example, the second direction is perpendicular to the first direction in the horizontal plane, such as Figure 7As shown, a cavity is formed in the second cooling plate 202, and the cavity is used to accommodate a cooling medium. A plurality of partitions e1 are arranged in the cavity, and the plurality of partitions e1 are extended along the first direction and spaced apart along the second direction. The plurality of partitions e1 divide the cavity into a plurality of flow channels d. More specifically, the second cooling plate 202 includes a first side c1 and a second side c2 that are oppositely arranged along the first direction, and two adjacent partitions e1 are respectively a first plate e2 and a second plate e3, wherein one end of the first plate e2 is connected to the first side c1, and the other end of the first plate e2 is spaced apart from the second side c2 (i.e. The other end of the first side plate directly forms a gap with the second side c2, and the cooling medium in the second side plate can pass through the gap). In this way, the flow channels d on both sides of the first plate e2 are connected, one end of the second plate e3 is connected to the second side c2, and the other end of the second side plate is spaced apart from the first side c1 (that is, the other end of the second side plate directly forms a gap with the first side c1, and the cooling medium in the second side plate can pass through the gap). The other partitions e1 are arranged according to the above-mentioned arrangement. In this way, multiple flow channels d are interconnected from head to tail to form a serpentine flow channel d.

[0086] It should be noted that the size of the flow channel d can be controlled by controlling the distance between two adjacent partitions e1. In this embodiment, considering the cooling effect, one single cell a corresponds to at least two flow channels d. More specifically, during the cooling process, as the cooling medium flows, the temperature of the cooling medium continues to rise, that is, the temperature of the cooling medium at the liquid inlet end is higher than the temperature of the cooling medium at the liquid outlet end. In this embodiment, the cooling medium in the second cooling plate 202 can flow through the same single cell a at least twice in succession, thereby improving the cooling efficiency and preventing the temperature of the single cell a from being too high and causing thermal runaway.

[0087] It should be noted that the type of cooling medium in the above embodiments is not limited and can be selected according to actual application conditions. For example, the cooling medium can be lubricating oil, water, cold air, alcohol compounds, etc.

[0088] Furthermore, each second cooling plate 202 is also connected to the first cooling plate 201, that is, the cooling medium in the second cooling plate 202 flows into the first cooling plate 201 after the cooling cycle is completed, and flows in from the first cooling plate 201. The connection method between the first cooling plate 201 and the plurality of second cooling plates 202 is not limited, and can be selected according to actual conditions. For example, two openings can be set on the second cooling plate 202, and corresponding inlets can be set on the first cooling plate 201, and the two openings are respectively connected to the two inlets, so as to achieve connection. For example, an additional infusion tube can also be set, one end of the infusion tube is connected to the second cooling plate 202, and the other end is connected to the first cooling plate 201, so as to connect the first cooling plate 201 and the second cooling plate 202.

[0089] See also Figure 5 The battery pack 1000 also includes a BMS control system 400, a data acquisition line 500, etc. The configuration and connection methods of the BMS control system 400 and the data acquisition line 500 can refer to the conventional configurations in the art and will not be described in detail here.

[0090] In some embodiments, the battery pack 1000 further includes a plurality of temperature sensors, which are electrically connected to the BMS system and are used to transmit detection signals to the BMS control system 400. Each temperature sensor is correspondingly arranged on each single cell a, and each temperature sensor is used to monitor the temperature of the corresponding single cell a. When the temperature of the single cell a is abnormal, the temperature sensor transmits the abnormal temperature to the BMS control system 400, and the BMS control system 400 transmits the abnormal signal, so that the user can detect the abnormality in time and avoid danger.

[0091] Of course, when the battery pack 1000 is working in winter or cold areas, in order to maintain the battery pack 1000 at the optimal working temperature of 25°C ± 3°C, the temperature of the cold medium in the first cooling plate 201 and the second cooling plate 202 can be adjusted by the BMS control system 400 to heat the battery pack 1000 so that the environment in the battery pack 1000 is 25°C ± 3°C (its principle is similar to heating in the north). When the temperature in the battery pack 1000 is lower than 20°C, the temperature sensor starts the alarm and transmits the information to the BMS control system 400, and the BMS control system 400 starts heating the battery pack 1000.

[0092] The present invention further proposes a gasket 10, which is used in a battery module 100. The gasket 10 is the gasket 10 in the battery module 100 in the above embodiment. The specific structure of the gasket 10 refers to the above embodiment. Since the gasket 10 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0093] In addition, the present invention also proposes an electric device, which includes a battery pack 1000. The specific structure of the battery pack 1000 refers to the above embodiment. Since the electric device adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0094] It is understood that electrical equipment includes but is not limited to electric toys, electric tools, battery cars, cars, ships, spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles and spacecrafts, etc. Cars can be fuel cars, gas cars and new energy cars.

[0095] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A battery module, characterized in that: include: a plurality of single cells (a); and, A plurality of gaskets (10), wherein the gaskets (10) are arranged between any two adjacent single cells (a), and the gaskets (10) are arranged to contact the surfaces of the single cells (a) after being melted by heat.

2. The battery module according to claim 1, characterized in that: The gasket (10) comprises a core material layer (1) and a packaging layer (2), wherein the packaging layer (2) is wrapped around the outside of the core material layer (1), the packaging layer (2) is in contact with the surface of the single battery (a), and the packaging layer (2) is at least partially melted by heat so that the core material layer (1) wraps around the surface of the single battery (a).

3. The battery module according to claim 2, characterized in that: At a first temperature, the core material layer (1) is fluid, at a second temperature, at least a portion of the encapsulation layer (2) melts, and at a third temperature, the core material layer (1) solidifies, the first temperature being lower than the second temperature, and the second temperature being lower than the third temperature.

4. The battery module according to claim 3, characterized in that: The first temperature is T1, the second temperature is T2, the third temperature is T3, T1<60°C, 60≤T2, T3≥100°C.

5. The battery module according to claim 2, characterized in that: The encapsulation layer (2) comprises a first side portion (21) and a second side portion (22) which are adjacent to each other, the first side portion (21) being in contact with the surface of the single battery (a), and the melting point of the first side portion (21) being higher than the melting point of the second side portion (22).

6. The battery module according to claim 5, characterized in that: The softening temperature of the first side portion (21) is T4, 400°C≤T4≤1000°C.

7. The battery module according to claim 5, characterized in that: The thickness of the core material layer (1) is H1, the thickness of the first side portion (21) is H2, H2 / H1=(0.05-0.1):1; and / or, The thickness of the core material layer (1) is H1, the thickness of the second side portion (22) is H3, and H3 / H1=(0.05-0.1):

1.

8. The battery module according to any one of claims 5 to 7, characterized in that: The core material layer (1) comprises resin; The first side portion (21) comprises any one of fireproof cloth, nylon, and polyamide-imide; The second side portion (22) comprises a polyethylene film.

9. The battery module according to any one of claims 5 to 7, characterized in that: The thermal conductivity of the first side portion (21) is lower than the thermal conductivity of the core material layer (1).

10. The battery module according to claim 1, characterized in that: Two gaskets (10) are arranged between any two adjacent single batteries (a); The battery module further comprises a plurality of thermal insulation pads (20), wherein the thermal insulation pads (20) are arranged between two of the gaskets (10).

11. The battery module according to claim 10, characterized in that: The thermal insulation pad (20) comprises any one of fireproof cloth, nylon, and polyamide-imide.

12. A battery pack, characterized in that: It comprises a plurality of battery modules (100) according to any one of claims 1 to 11.

13. The battery pack according to claim 12, characterized in that: It also includes a cooling device (200), wherein a plurality of the battery modules (100) are connected to the cooling device (200), and the gasket (10) is melted by heat and then filled between the single battery (a) and the cooling device (200).

14. The battery pack according to claim 13, characterized in that: The cooling device (200) comprises a plurality of second cooling plates (202), and a second cooling plate (202) is arranged between two adjacent battery modules (200).

15. The battery pack according to claim 13, characterized in that: The cooling device (200) comprises a first cooling plate (201), a plurality of the battery modules (100) are arranged on the first cooling plate (201), and the gasket (10) is melted by heat to fill the gap between the single battery (a) and the first cooling plate (201).

16. The battery pack according to claim 15, characterized in that: The cooling device (200) further comprises a plurality of second cooling plates (202), wherein the plurality of second cooling plates (202) are arranged on the first cooling plate (201), and a second cooling plate (202) is arranged between two adjacent battery modules (100). After the gasket (10) is melted by heat, it fills the gap between the single battery (a) and the plurality of second cooling plates (202).

17. The battery pack according to claim 16, characterized in that: The gasket (10) melted by heat is connected between the single battery (a) and the first cooling plate (201), and is also connected between the single battery (a) and a plurality of the second cooling plates (202).

18. The battery pack according to any one of claims 12 to 17, characterized in that: It also includes a plurality of temperature sensors, each of which is correspondingly arranged on each of the single cells (a) for monitoring the temperature of the corresponding single cell (a).

19. A gasket, characterized in that: Used in a battery module (100), the gasket (10) is the gasket (10) in the battery module according to any one of claims 1 to 11.

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