Multi-packaging structure and battery

Abstract

The utility model provides a multi-packaging structure and a battery, the multi-packaging structure comprises a first packaging film and a second packaging film, the first packaging film is provided with a first groove and a first sealing edge, and at least three sides of the first sealing edge are distributed around the first groove; the second packaging film is connected with the first packaging film, the second packaging film is provided with a second groove and a second sealing edge, and at least three sides of the second sealing edge are distributed around the second groove; the first sealing edge and the second sealing edge are connected to define an edge sealing area, the first groove and the second groove define a containing cavity, the edge sealing area comprises a first sealing area and a second sealing area which are arranged in a spaced mode, and the first sealing area is located on the side, close to the containing cavity, of the second sealing area. At least one of the first sealing area and the second sealing area is provided with a first sub-sealing area and a second sub-sealing area, the first sub-sealing area is located on the side, close to the containing cavity, of the second sub-sealing area, and the thickness of the first sub-sealing area is larger than that of the second sub-sealing area. According to the multi-packaging structure and the battery, the safety can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a multiple packaging structure and a battery. BACKGROUND

[0002] Aluminum plastic film is used to package the battery cell to avoid leakage of electrolyte and to block contact of moisture and oxygen in the environment with the battery cell. However, in a high-temperature environment, the battery cell will generate a large amount of gas, causing the containment cavity of the aluminum plastic film to expand and pressurize until the aluminum plastic film is damaged, which will cause a large impact. In addition, the generation of gas by the battery cell is accompanied by the release of heat, and with the accumulation of heat, there is a risk of smoking and fire, making it difficult to ensure the safety of the battery. CONTENT OF THE UTILITY MODEL

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a multiple packaging structure that can improve the safety of the battery.

[0004] The present application also proposes a battery having the above-mentioned multiple packaging structure.

[0005] According to the multiple packaging structure of the embodiments of the present application, the multiple packaging structure comprises a first packaging film and a second packaging film;

[0006] The first packaging film is provided with a first recess and a first sealing edge, and the first sealing edge is distributed around the first recess on at least three sides;

[0007] The second packaging film is connected with the first packaging film, and the second packaging film is provided with a second recess and a second sealing edge, and the second sealing edge is distributed around the second recess on at least three sides;

[0008] The first sealing edge and the second sealing edge are connected to define a sealing edge area, the first recess and the second recess jointly define a containment cavity, the sealing edge area comprises a first sealing area and a second sealing area arranged at intervals, the first sealing area is located on the side of the second sealing area close to the containment cavity, at least one of the first sealing area and the second sealing area is provided with a first sub-sealing area and a second sub-sealing area, and in the first sealing area and the second sealing area, the first sub-sealing area is located on the side of the second sub-sealing area close to the containment cavity;

[0009] In the first direction, the thickness of the first sub-sealing area is greater than the thickness of the second sub-sealing area.

[0010] According to the multi-packaging structure, the accommodation cavity is used for accommodating the battery cell, the edge sealing region is divided into the first sealing area and the second sealing area, and the first sealing area and the second sealing area are used for jointly ensuring the sealing of the accommodation cavity. When the edge sealing region is broken, the first sealing area and the second sealing area can be broken in sequence. At least one of the first sealing area and the second sealing area is provided with the first sub-sealing area and the second sub-sealing area, that is, the first sub-sealing area is used for corresponding to the groove of the packaging mold during packaging, so that the first sub-sealing area is subjected to a smaller degree of pressing than the second sub-sealing area, and further, the sealing strength of the first sub-sealing area is smaller than the sealing strength of the second sub-sealing area. In the first sealing area and the second sealing area, the first sub-sealing area is located on the side of the second sub-sealing area close to the accommodation cavity, the first sub-sealing area is used for breaking the gas first, and then the second sub-sealing area adjacent to the first sub-sealing area is broken, so that the edge sealing region is broken gradually, the breaking of the edge sealing region is more moderate, the weak sealing strength of the first sub-sealing area is beneficial to reducing the breaking difficulty, and the timely breaking of the edge sealing region avoids fire and explosion, and is beneficial to improving the safety of the battery.

[0011] According to some embodiments of the present application, the multi-packaging structure comprises a first side, a second side, a third side and a fourth side connected in sequence, the first side and the third side are oppositely arranged along a second direction, the second side and the fourth side are oppositely arranged along a third direction, the first packaging film and the second packaging film are connected at the first side, the first edge and the second edge are connected at the second side, the third side and the fourth side to form an edge sealing region, and the first direction, the second direction and the third direction are perpendicular to each other in pairs.

[0012] The third side is used for leading out the tab, and the first sub-sealing area is located on at least one of the second side and the fourth side.

[0013] According to some embodiments of the present application, the first sealing area and the second sealing area are each provided with the first sub-sealing area and the second sub-sealing area.

[0014] In the first sealing area and the second sealing area, the first sub-sealing area is distributed around the accommodation cavity on the second side, the third side and the fourth side, and the second sub-sealing area is distributed around the first sub-sealing area on the second side, the third side and the fourth side.

[0015] According to some embodiments of the present application, along the direction of the first sub-sealing area away from the accommodation cavity, the first sub-sealing area at least includes a guide section with a gradually decreasing cross-sectional area.

[0016] According to some embodiments of the present application, the edge sealing region is provided with a notch portion at the junction area of the second side and the third side.

[0017] And / or, the edge sealing region is provided with a notch portion at the junction area of the third side and the fourth side.

[0018] According to some embodiments of the present application, the edge sealing region further comprises a first spacing region, the first spacing region is located between the first sealing region and the second sealing region, and the first edge sealing and the second edge sealing abut at the first spacing region.

[0019] According to some embodiments of the present application, the width of the first spacing region on either side of the accommodating cavity is a, and 0.1mm≥a≥1.5mm.

[0020] According to some embodiments of the present application, on either side of the accommodating cavity, the sum of the widths of the first sealing region and the second sealing region is b, and the width of the first sub-sealing region is c, b-c≥1mm.

[0021] According to some embodiments of the present application, the multi-packaging structure further comprises a third sealing region and a second spacing region, the third sealing region is spaced apart from the second sealing region on a side of the second sealing region away from the accommodating cavity, and the second spacing region is located between the second sealing region and the third sealing region.

[0022] The battery according to the embodiments of the present application comprises a battery cell and the multi-packaging structure according to any one of the embodiments described above, and the battery cell is located in the accommodating cavity.

[0023] The battery according to the embodiments of the present application has at least the following beneficial effects: the battery cell is packaged by the multi-packaging structure according to the present application, which can sequentially break through the sealing regions of the edge sealing region when the battery is subjected to high temperature, and timely realize pressure relief and heat dissipation in the accommodating cavity, effectively avoiding accidents such as explosion and fire caused by excessive pressure or temperature in the accommodating cavity, and is beneficial to ensuring the safety of the battery.

[0024] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0025] The present application will be further described below in conjunction with the drawings and embodiments, in which:

[0026] Figure 1 FIG. 1 is a structural schematic diagram of a battery according to an embodiment of the present application;

[0027] Figure 2 FIG. 2 is a sectional view of A-A in FIG. 1; Figure 1

[0028] Figure 3 FIG. 3 is a partial enlarged schematic view of B in FIG. 2; Figure 2

[0029] Figure 4 FIG. 4 is a sectional view of an edge sealing region in another embodiment of the present application;

[0030] Figure 5 FIG. 5 is a structural schematic diagram of a battery according to another embodiment of the present application; ​​

[0031] Figure 6 For Figure 5 A sectional view at C-C;

[0032] Figure 7 A structural schematic diagram of a battery according to another embodiment of the present application;

[0033] Figure 8 For Figure 7 A partial enlarged schematic view at D.

[0034] Reference signs: first encapsulation film 100, first groove 110, first edge 120;

[0035] Second encapsulation film 200, second groove 210, second edge 220;

[0036] Receiving cavity 300, first side 310, second side 320, third side 330, fourth side 340;

[0037] Edge sealing area 400, first sealing area 410, first guide section 411, second guide section 412, second sealing area 420, third sealing area 430, first sub-sealing area 440, second sub-sealing area 450, first spacing area 460, second spacing area 470, notch part 480;

[0038] Battery cell 500. DETAILED DESCRIPTION

[0039] The embodiments of the present application are described in detail below with reference to the accompanying drawings. The embodiments described below are examples for explaining the present application and should not be understood as limiting the present application.

[0040] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0041] In the description of the present application, if the meaning of several is more than one, the meaning of multiple is two or more, greater than, less than, more than, etc. is understood as not including the number, above, below, etc. is understood as including the number. If it is described as first, second, etc. is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of indicated technical features.

[0042] In the description of the present application, the words such as arrangement, installation, connection and the like should be understood in a broad sense, and the specific meanings of the words in the present application can be determined by the person skilled in the art in combination with the specific content of the technical solutions.

[0043] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0044] The embodiments of the present application are described below in combination with the accompanying drawings:

[0045] Reference Figures 1 to 6 According to the multi-packaging structure of the present application, the multi-packaging structure comprises a first packaging film 100 and a second packaging film 200. The first packaging film 100 comprises a first recess 110 and a first sealing edge 120. The first sealing edge 120 is distributed around the first recess 110 on at least three sides. The second packaging film 200 is connected with the first packaging film 100. The second packaging film 200 comprises a second recess 210 and a second sealing edge 220. The second sealing edge 220 is distributed around the second recess 210 on at least three sides. The first sealing edge 120 is connected with the second sealing edge 220 to define a sealing edge area 400. The first recess 110 and the second recess 210 jointly define a containing cavity 300. The containing cavity 300 is used for containing an electric core 500. The sealing edge area 400 comprises a first sealing area 410 and a second sealing area 420. The first sealing area 410 is located on the side of the second sealing area 420 close to the containing cavity 300. At least one of the first sealing area 410 and the second sealing area 420 is provided with a first sub-sealing area 440 and a second sub-sealing area 450. In the first sealing area 410 and the second sealing area 420, the first sub-sealing area 440 is located on the side of the second sub-sealing area 450 close to the containing cavity 300. In the first direction, the thickness of the first sub-sealing area 440 is greater than the thickness of the second sub-sealing area 450. The thickness is used to ensure that the sealing strength of the first sub-sealing area 440 is weaker than the sealing strength of the second sub-sealing area 450. When the battery is subjected to high temperature, the first sub-sealing area 440 and the second sub-sealing area 450 are sequentially broken in the first sealing area 410 and / or the second sealing area 420, which is beneficial to improve the safety of the battery.

[0046] The interval between the first sealing area 410 and the second sealing area 420 can be understood as an area where the first sealing edge 120 and the second sealing edge 220 are not pressed and sealed by the packaging mold, or an area with a relatively greater thickness than the first sub-sealing area 440.

[0047] In the above, the thickness of the first sub-sealing area 440 is greater than the thickness of the second sub-sealing area 450, which can be understood as follows: when the first sealing edge 120 and the second sealing edge 220 are pressed and sealed by the packaging mold to form a sealing area, the first sub-sealing area 440 corresponds to the groove position of the packaging mold, so that the pressing degree of the first sub-sealing area 440 is less than the pressing degree of the second sub-sealing area 450. Thus, the sealing strength of the first sub-sealing area 440 is less than the sealing strength of the second sub-sealing area 450, and therefore, on the basis of ensuring the sealing of the accommodation cavity 300, the first sub-sealing area 440 can be used to allow the gas accumulated in the accommodation cavity 300 to break through first, and then break through the second sub-sealing area 450 adjacent to the first sub-sealing area 440, and when the first sealing area 410 and the second sealing area 420 are broken, the battery can be relieved by sequentially breaking the first sub-sealing area 440 and the second sub-sealing area 450, and the gas discharged can take out the heat in the accommodation cavity 300, thereby avoiding the continuous accumulation of heat in the accommodation cavity 300 and causing smoking and fire, and improving the safety of the battery.

[0048] It should be noted that, compared with a packaging structure in which the sealing strength of the sealing edge is uniform, the multiple packaging structure in the present application has the following advantages: on the basis of ensuring sealing (i.e., on the basis of the sealing width of any side of the accommodation cavity 300 being unchanged), the multiple packaging structure can sequentially break through the sealing areas (i.e., on the basis of breaking through the sealing edge area 400 on any side of the accommodation cavity 300), which is easier to break through, and facilitates timely pressure relief when the battery is subjected to high temperature. In addition, the multiple packaging structure has the first sub-sealing area 440 and the second sub-sealing area 450 with different sealing strengths, which can gradually break through the sealing areas and make the process of breaking through the sealing edge area 400 more stable and the pressure relief more stable, thereby reducing the impact caused by breaking through the packaging structure.

[0049] In addition, Figure 3 , Figure 4 and Figure 6 Each smaller dashed box in the above represents the area division of the first sub-sealing area 440 and the second sub-sealing area 450.

[0050] Referring to Figures 1 to 3 , specifically, the first sealing edge 120 and the second sealing edge 220 each include a heat-seal layer, for example, a polypropylene film on the side where the first sealing edge 120 and the second sealing edge 220 contact each other. When the first sealing edge 120 and the second sealing edge 220 are heated, the heat-seal layer of the first sealing edge 120 and the second sealing edge 220 can be melted, so that the first sealing edge 120 and the second sealing edge 220 are connected to define the sealing edge area 400.

[0051] The first sealing edge 120 and the second sealing edge 220 are connected by heat sealing of the sealing mold to form a sealing edge area 400, the sealing edge area 400 at least includes a first sealing area 410 and a second sealing area 420, and at least one of the first sealing area 410 and the second sealing area 420 further includes a first sub-sealing area 440 and a second sub-sealing area 450, the sealing mold is provided with a groove corresponding to the first sub-sealing area 440, the groove is used to avoid forming the first sub-sealing area 440, the first sub-sealing area 440 is thicker than the second sub-sealing area 450, so as to reduce the sealing strength of the first sealing area 410. The first sub-sealing area 440 is located on the side of the second sub-sealing area 450 close to the accommodation cavity 300. Since the gas accumulated in the accommodation cavity 300 at high temperature can first break through the first sub-sealing area 440 with weak sealing, and then break through the second sub-sealing area 450 adjacent to the first sub-sealing area 440 and thinner, an exhaust port is formed, the pressure in the accommodation cavity 300 is released, and heat is discharged outward, effectively reducing the risk of battery smoke and fire, and improving the safety of the battery.

[0052] It should be noted that the thickness of the first sub-sealing area 440 is greater than the thickness of the second sub-sealing area 450 should be understood as the thickness of the thinnest area of the first sub-sealing area 440 is greater than the thickness of the thickest area of the second sub-sealing area 450.

[0053] Reference Figures 1 to 8 In other embodiments, at least one of the first sealing area 410 and the second sealing area 420 includes a plurality of first sub-sealing areas 440, for example, the first sub-sealing area 440 and the second sub-sealing area 450 are provided in the first sealing area 410, the first sub-sealing area 440 has a plurality of first sub-sealing areas 440, which can be distributed on one side, two sides, three sides or four sides of the accommodation cavity 300. On any side of the accommodation cavity 300, along the width direction of the first sealing area 410, each first sub-sealing area 440 is located on the side of the second sub-sealing area 450 close to the accommodation cavity 300, and along the length direction of the first sealing area 410, each first sub-sealing area 440 is spaced apart from each other. When the battery is subjected to high temperature, the sealing edge area 400 can be broken in the area where each first sub-sealing area 440 is located, forming a plurality of exhaust ports, and the pressure relief is more stable.

[0054] For example, the first sealing area 410 and the second sealing area 420 are each provided with a first sub-sealing area 440 and a second sub-sealing area 450, and the first sealing area 410 and the second sealing area 420 each have a plurality of first sub-sealing areas 440, which can be distributed on one side, two sides, three sides, or four sides of the accommodation cavity 300. The first sealing area 410 and the second sealing area 420 are arranged along the width direction of the sealing edge area 400, and the first sealing area 410 is located on the side of the second sealing area 420 close to the accommodation cavity 300. On any side of the accommodation cavity 300, along the width direction of the sealing edge area 400, in the first sealing area 410 and the second sealing area 420, each first sub-sealing area 440 is located on the side of the second sub-sealing area 450 close to the accommodation cavity 300, and along the length direction of the sealing edge area 400, each first sub-sealing area 440 is arranged separately from each other. When the battery is subjected to high temperature, the sealing edge area 400 can be broken in the area where each first sub-sealing area 440 is located, forming a plurality of gas outlets, and the pressure relief is more stable.

[0055] It should be noted that the width direction of the sealing edge area 400 can be different on different sides of the accommodation cavity 300. For example, the width direction of the sealing edge area 400 on the adjacent two sides of the accommodation cavity 300 can be perpendicular to each other.

[0056] Reference Figures 1 to 3 In some embodiments, the multi-pack structure includes a first side 310, a second side 320, a third side 330, and a fourth side 340 connected in sequence, the first side 310 and the third side 330 are arranged opposite to each other along a second direction, the second side 320 and the fourth side 340 are arranged opposite to each other along a third direction, the first packaging film 100 and the second packaging film 200 are connected at the first side 310, the first sealing edge 120 and the second sealing edge 220 are connected at the second side 320, the third side 330, and the fourth side 340 to form a sealing edge area 400, that is, the first sealing edge 120 surrounds the first recess 110 at the second side 320, the third side 330, and the fourth side 340, and the second sealing edge 220 surrounds the second recess 210 at the second side 320, the third side 330, and the fourth side 340, so that the sealing edge area 400 surrounds the accommodation cavity 300 on three sides. The first direction, the second direction, and the third direction are perpendicular to each other in pairs, the first direction can be the thickness direction of the packaging structure, the second direction can be the length direction of the packaging structure, and the third direction can be the width direction of the packaging structure.

[0057] The third side 330 of the multi-packaging structure is used for leading out the tab, and the first sub-sealing area 440 is located on at least one of the second side 320 and the fourth side 340. The third side 330 is more complex in packaging due to the presence of the tab compared with the second side 320 and the fourth side 340. Therefore, the first sub-sealing area 440 is arranged on at least one of the second side 320 and the fourth side 340 to avoid the tab leading-out side, so as to facilitate the packaging of the packaging structure and reduce the packaging difficulty.

[0058] Referring to Figures 1 to 8 In some other embodiments, the second side 320, the third side 330 and the fourth side 340 of the multi-packaging structure are each provided with the second sub-sealing area 450, and the second side 320 is provided with the first sub-sealing area 440. The first sub-sealing area 440 is located on the side of the second sub-sealing area 450 close to the accommodating cavity 300, and is used for the battery to break through the sealing edge area 400 on the second side 320 when suffering high temperature.

[0059] Referring to Figures 1 to 8 In some other embodiments, the second side 320, the third side 330 and the fourth side 340 of the multi-packaging structure are each provided with the second sub-sealing area 450, and the third side 330 is provided with the first sub-sealing area 440. The first sub-sealing area 440 is located on the side of the second sub-sealing area 450 close to the accommodating cavity 300, and is used for the battery to break through the sealing edge area 400 on the third side 330 when suffering high temperature.

[0060] Referring to Figures 1 to 8 In some other embodiments, the second side 320, the third side 330 and the fourth side 340 of the multi-packaging structure are each provided with the second sub-sealing area 450, and the fourth side 340 is provided with the first sub-sealing area 440. The first sub-sealing area 440 is located on the side of the second sub-sealing area 450 close to the accommodating cavity 300, and is used for the battery to break through the sealing edge area 400 on the fourth side 340 when suffering high temperature.

[0061] Referring to Figures 1 to 8 In some other embodiments, the second side 320, the third side 330 and the fourth side 340 of the multi-packaging structure are each provided with the second sub-sealing area 450, and the second side 320 and the third side 330 are provided with the first sub-sealing area 440. The first sub-sealing area 440 is located on the side of the second sub-sealing area 450 close to the accommodating cavity 300, and is used for the battery to break through the sealing edge area 400 on the second side 320 and the third side 330 when suffering high temperature.

[0062] Referring to Figures 1 to 8In some embodiments, the first sealing area 410 and the second sealing area 420 are each provided with a first sub-sealing area 440 and a second sub-sealing area 450. In the first sealing area 410 and the second sealing area 420, the first sub-sealing area 440 is distributed around the accommodation cavity 300 on the second side 320, the third side 330 and the fourth side 340, and the second sub-sealing area 450 is distributed around the first sub-sealing area 440 on the second side 320, the third side 330 and the fourth side 340, i.e., the first sub-sealing area 440 is surrounded by the second side 320, the third side 330 and the fourth side 340, and the second sub-sealing area 450 is surrounded by the first sub-sealing area 440. When the battery is subjected to high temperature, the gas generated by the battery will sequentially break through the first sub-sealing area 440 and the second sub-sealing area 450 in the first sealing area 410, and the first sub-sealing area 440 and the second sub-sealing area 450 in the second sealing area 420. After the first sealing area 410 is broken, the space for accommodating the gas is further expanded, which can relieve the expansion of the multi-packaging structure, and then further break the second sealing area 420 to achieve the pressure relief and heat dissipation of the battery, so as to avoid the explosion or fire of the battery caused by high temperature, and improve the safety of the battery.

[0063] Reference Figures 1 to 6 In some embodiments, the first sealing area 410 and the second sealing area 420 are each provided with a first sub-sealing area 440 and a second sub-sealing area 450. In the first sealing area 410 and the second sealing area 420, the first sub-sealing area 440 is distributed around the accommodation cavity 300 on the second side 320, the third side 330 and the fourth side 340, and the second sub-sealing area 450 is distributed around the first sub-sealing area 440 on the second side 320, the third side 330 and the fourth side 340, i.e., the first sub-sealing area 440 is surrounded by the second side 320, the third side 330 and the fourth side 340, and the second sub-sealing area 450 is surrounded by the first sub-sealing area 440. When the battery is subjected to high temperature, the gas generated by the battery will sequentially break through the first sub-sealing area 440 and the second sub-sealing area 450 in the first sealing area 410, and the first sub-sealing area 440 and the second sub-sealing area 450 in the second sealing area 420. After the first sealing area 410 is broken, the space for accommodating the gas is further expanded, which can relieve the expansion of the multi-packaging structure, and then further break the second sealing area 420 to achieve the pressure relief and heat dissipation of the battery, so as to avoid the explosion or fire of the battery caused by high temperature, and improve the safety of the battery.

[0064] Reference Figures 5 to 8 In some embodiments, the first sealing area 410 and the second sealing area 420 are each provided with a first sub-sealing area 440 and a second sub-sealing area 450. In the first sealing area 410 and the second sealing area 420, the first sub-sealing area 440 is distributed around the accommodation cavity 300 on the second side 320, the third side 330 and the fourth side 340, and the second sub-sealing area 450 is distributed around the first sub-sealing area 440 on the second side 320, the third side 330 and the fourth side 340, i.e., the first sub-sealing area 440 is surrounded by the second side 320, the third side 330 and the fourth side 340, and the second sub-sealing area 450 is surrounded by the first sub-sealing area 440. When the battery is subjected to high temperature, the gas generated by the battery will sequentially break through the first sub-sealing area 440 and the second sub-sealing area 450 in the first sealing area 410, and the first sub-sealing area 440 and the second sub-sealing area 450 in the second sealing area 420. After the first sealing area 410 is broken, the space for accommodating the gas is further expanded, which can relieve the expansion of the multi-packaging structure, and then further break the second sealing area 420 to achieve the pressure relief and heat dissipation of the battery, so as to avoid the explosion or fire of the battery caused by high temperature, and improve the safety of the battery.

[0065] It should be noted that after the first sealing area 410 is broken, the space for accommodating the gas is increased, and the gas pressure in the accommodation cavity 300 is relieved, and then the second sealing area 420 is broken, so that the breaking process is more stable, and the first sealing area 410 and the second sealing area 420 are each provided on three sides of the accommodation cavity 300, which facilitates the breaking of a larger opening for pressure relief and heat dissipation, and is beneficial to further improve the safety of the battery.

[0066] Reference Figures 5 to 8In some embodiments, the first sub-sealing area 440 includes at least a guiding section with a gradually decreasing cross-sectional area in a direction away from the accommodating cavity 300, and the guiding section is configured to guide the gas in the accommodating cavity 300 to generate a greater gas pressure in the first sub-sealing area 440, so as to more easily break through the sealing edge area 400.

[0067] In the direction away from the accommodating cavity 300, the gradually decreasing cross-sectional area of the guiding section is understood as follows: taking the side of the guiding section close to the accommodating cavity 300 as the bottom and the side of the guiding section away from the accommodating cavity 300 as the top, the guiding section is cut by a plurality of planes perpendicular to the connecting line of the bottom and the top of the guiding section, and the cross-sectional area gradually decreases from the bottom to the top.

[0068] In addition, the guiding section can be triangular or conical in structure when cut by a plane perpendicular to the first direction.

[0069] Reference Figures 1 to 8 The guiding section includes a first guiding section 411 and a second guiding section 412, the cross-sectional area of the first guiding section 411 gradually decreases in the direction away from the accommodating cavity 300, the second guiding section 412 is connected to the side of the first guiding section 411 close to the accommodating cavity 300, and the cross-sectional area of the second guiding section 412 is constant, the second guiding section 412 is configured to provide a weak sealing area for the packaging structure and ensure the sealing of the packaging structure, and when the gas pressure breaks through the second guiding section 412 and the first guiding section 411 in turn, the first guiding section 411 is configured to guide the gas to further break through the second sealing area 420, so as to more easily break through the second sealing area 420 and achieve the pressure relief of the battery. Therefore, the first guiding section 411 and the second guiding section 412 can ensure the sealing of the sealing edge area 400 and make it easier to break through the sealing edge area 400 when the gas pressure is greater.

[0070] In the direction away from the accommodating cavity 300, the cross-sectional area of the second guiding section 412 is understood as the cross-sectional area generated by cutting the second guiding section 412 by a plane perpendicular to the direction of the first sealing area 410.

[0071] In addition, in the first direction, the thicknesses of the first guiding section 411 and the second guiding section 412 are greater than that of the second sub-sealing area 450, that is, the sealing strengths of the first guiding section 411 and the second guiding section 412 are less than that of the second sub-sealing area 450.

[0072] Reference Figure 5In some embodiments, the edge sealing region 400 is provided with a cutout portion 480 at the junction between the second side 320 and the third side 330 of the multi-pack structure, which is used to avoid interference between the edge sealing regions 400 on the second side 320 and the third side 330 when they are bent, facilitating the bending of the edge sealing regions 400 on the second side 320 and the third side 330, reducing the space occupied by the battery, and / or the edge sealing region 400 is provided with a cutout portion 480 at the junction between the third side 330 and the fourth side 340, which is used to avoid interference between the edge sealing regions 400 on the third side 330 and the fourth side 340 when they are bent, facilitating the bending of the edge sealing regions 400 on the third side 330 and the fourth side 340, reducing the space occupied by the battery.

[0073] Specifically, the multi-pack structure comprises a first side 310, a second side 320, a third side 330 and a fourth side 340 connected in sequence and distributed around the accommodation cavity 300, the first edge sealing 120 is distributed on the second side 320, the third side 330 and the fourth side 340, and the second edge sealing 220 is also distributed on the second side 320, the third side 330 and the fourth side 340, and then the edge sealing region 400 formed by the connection of the first edge sealing 120 and the second edge sealing 220 surrounds the accommodation cavity 300 on three sides, the edge sealing region 400 at the junction between the second side 320 and the third side 330, and the edge sealing region 400 at the junction between the third side 330 and the fourth side 340, both of which are provided with a cutout portion 480, which is used to avoid interference between the edge sealing regions 400 on the second side 320 and the third side 330 during the edge bending operation, and to avoid interference between the edge sealing regions 400 on the third side 330 and the fourth side 340 during the edge bending operation.

[0074] Reference Figure 6 and Figure 5 In some embodiments, the edge sealing region 400 further comprises a first spacing region 460 between the first sealing region 410 and the second sealing region 420, and the first edge sealing 120 and the second edge sealing 220 abut at the first spacing region 460, that is, in the first spacing region 460, the first edge sealing 120 and the second edge sealing 220 only maintain adhesion, when the gas rushes into the first spacing region 460, the first edge sealing 120 and the second edge sealing 220 separate, forming a buffer zone for the pressure relief of the gas, and then breaking through the next sealing region, the provision of the first spacing region 460 is beneficial to ensure the stable pressure relief of the battery.

[0075] Reference Figure 6 and Figures 1 to 8In some embodiments, the width of the first spacing area 460 on either side of the accommodation cavity 300 is a, and 0.1 mm≥a≥1.5 mm, which defines the lower limit of the width of the first spacing area 460 for separating the sealing areas to facilitate pressure relief when the battery encounters high temperature, and which defines the upper limit of the width of the first spacing area 460 for avoiding that the edge sealing area 400 is too wide, thereby reducing the space occupied by the folded edge on the basis of ensuring the sealing of the multi-packaging structure, and being beneficial to improving the energy density of the battery.

[0076] For example, a can be any value of 0.1 mm, 0.3 mm, 0.5 mm, 0.7 mm, 0.9 mm, 1.1 mm, 1.3 mm, or 1.5 mm.

[0077] It should be noted that the width direction of the edge sealing area 400 on the third side 330 is the second direction, and the width direction of the edge sealing area on the second side 320 and the fourth side 340 is the third direction.

[0078] Reference Figure 5 In some embodiments, on either side of the accommodation cavity 300, the sum of the widths of the first sealing area 410 and the second sealing area 420 is b (single-side width), and the width of the first sub-sealing area 440 is c (single-side width), then b-c≥1 mm, which is used to ensure the sealing of the packaging structure, avoid the leakage of electrolyte in the accommodation cavity 300, and block the air and moisture in the environment from entering the accommodation cavity 300, so that the performance of the battery is more stable.

[0079] Specifically, at least one of the first sealing area 410 and the second sealing area 420 is provided with the first sub-sealing area 440 and the second sub-sealing area 450, and the sealing strength of the second sub-sealing area 450 is higher than that of the first sub-sealing area 440. Therefore, the width of the second sub-sealing area 450 needs to be ensured to ensure the sealing of the accommodation cavity 300, and b-c represents the sum of the width of the second sub-sealing area 450 at the narrowest part of the first sealing area 410 and the width of the second sub-sealing area 450 at the narrowest part of the second sealing area 420 on either side of the accommodation cavity 300.

[0080] It should be understood that if the first sealing area 410 is not provided with the first sub-sealing area 440, the thickness of the first sealing area 410 is the same as that of the second sub-sealing area 450, and the first sealing area 410 is equivalent to being provided with the second sub-sealing area 450.

[0081] Alternatively, the second sealing area 420 is not provided with the first sub-sealing area 440, and the thickness of the second sealing area 420 is the same as that of the second sub-sealing area 450, and the second sealing area 420 is equivalent to being provided with the second sub-sealing area 450.

[0082] If the first sealing area 410 and the second sealing area 420 are both provided with the first sub-sealing area 440, on any side of the accommodating cavity 300, c represents the sum of the widths of the first sub-sealing areas 440 in the first sealing area 410 and the second sealing area 420.

[0083] It should be noted that the value range of b-c can be any size in 1mm to 10mm, for example, the value of b-c can be any value in 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm, by adjusting the sum of the width values of the narrowest parts of each second sub-sealing area 450, it is beneficial to better balance the sealing performance and safety of the battery, avoid the width of the second sub-sealing area 450 being too small in the sealing area 400 and leaking, and also avoid the width of the second sub-sealing area 450 being too large in the sealing area 400 and being difficult to break through the sealing area 400, on the basis of ensuring the sealing performance of the sealing area 400, avoid occupying a large space, and it is beneficial to improve the energy density of the battery.

[0084] Reference Figure 6 And Figures 1 to 8 In some embodiments, the multi-packaging structure further comprises a third sealing area 430 and a second spacing area 470, the third sealing area 430 is arranged on the side of the second sealing area 420 away from the accommodating cavity 300, and the second spacing area 470 is located between the second sealing area 420 and the third sealing area 430, the second spacing area 470 is used to provide further buffering for the pressure relief of the battery, the pressure relief of the battery is more stable, and on the basis of the unchanged width of the sealing area 400, the number of sealing areas can be further increased, the width of each sealing area can be reduced, so that it is easier for the battery to break through a single sealing area when it is subjected to high temperature, and the pressure relief is more timely, which is beneficial to improve the safety of the battery.

[0085] Reference Figures 1 to 8 The multi-packaging structure is further described as follows in combination with the production process of the multi-packaging structure in the present application:

[0086] Firstly, the packaging mold for producing the multi-packaging structure in the application includes a first head and a second head, and the side of the first head and the second head facing each other is provided with a groove, the position of the groove corresponds to the position of the first sub-sealing area 440, and the number of grooves can be multiple. In the edge sealing operation, the multiple grooves are arranged along the width direction of the edge sealing area 400. It should be understood that the area corresponding to the first sub-sealing area 440 of the first head and the second head is a flush plane. When the first head and the second head jointly heat seal the first edge 120 and the second edge 220, the first sub-sealing area 440 can be formed at the position corresponding to the groove in the first sealing area 410 and the second sealing area 420 by avoiding the groove. The edge sealing area 400 is not heat sealed and compressed or is less heat sealed and compressed at the position corresponding to the groove, so that a relatively thin second sub-sealing area 450 is formed at the position without the groove, and a relatively thick first sub-sealing area 440 is formed at the position with the groove. The sealing strength of the second sub-sealing area 450 is greater than that of the first sub-sealing area 440.

[0087] Secondly, at the positions of the first head and the second head corresponding to the first interval area 460 and the second interval area 470, a deeper interval groove is arranged to avoid the first interval area 460 and the second interval area 470, so as to avoid heat sealing the edge sealing area 400 at the positions corresponding to the first interval area 460 and the second interval area 470, and form a buffer in the first interval area 460 and the second interval area 470.

[0088] In addition, in the sealing operation, in order to make the sealing strength of the first sub-sealing area 440 and the second sub-sealing area 450 have a more obvious difference, the thickness of the polypropylene layer of the first edge 120 and the second edge 220 can be adjusted, so that the position corresponding to the second sub-sealing area 450 can be heat sealed to a greater extent, thereby increasing the thickness difference between the first sub-sealing area 440 and the second sub-sealing area 450, and the sealing strength of the two is further increased.

[0089] It should be noted that, in order to avoid sealing the first interval area 460 and the second interval area 470, the first edge 120 and the second edge 220 can not be provided with a polypropylene layer at the positions corresponding to the first interval area 460 and the second interval area 470.

[0090] Reference ​ According to the battery of the application, the battery includes a battery cell 500 and a multi-packaging structure in any of the above embodiments, and the multi-packaging structure defines a containing cavity 300. The battery cell 500 is located in the containing cavity 300. Through the packaging of the battery cell 500 by the multi-packaging structure, the edge sealing area 400 can be sequentially broken in zones when the battery encounters a high-temperature environment, the internal gas pressure and the temperature are prevented from being too high, and the safety of the battery is beneficially ensured.

[0091] Specifically, the first encapsulation film 100 and the second encapsulation film 200 are always connected at the first side 310, the battery cell 500 is placed in the first recess 110 or the second recess 210, the first encapsulation film 100 and the second encapsulation film 200 are oppositely flipped and buckled, the first recess 110 and the second recess 210 define the accommodation cavity 300, and then the first sealing edge 120 and the second sealing edge 220 are heat-sealed to realize the sealing of the accommodation cavity 300.

[0092] It should be noted that the battery can also improve the safety of the battery in the battery hot box test process. During the battery hot box test process, as the temperature rises, the battery will produce serious inflation. The gas in the accommodation cavity 300 can sequentially break through the first sealing area 410 and the second sealing area 420, and sequentially break through the first sub-sealing area 440 and the second sub-sealing area 450 in the first sealing area 410 and the second sealing area 420, to avoid explosion and fire caused by excessive gas pressure and high temperature in the accommodation cavity 300, and to improve the safety of the battery.

[0093] The above describes the embodiments of the application in detail in combination with the drawings, but the application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the purpose of the application. In addition, the embodiments of the application and the features in the embodiments can be combined with each other without conflict.

Claims

1. A multiple package structure having a thickness direction, characterized by, include: A first encapsulation film has a first groove and a first sealing edge, wherein the first sealing edge is distributed around the first groove on at least three sides; A second encapsulation film is connected to the first encapsulation film. The second encapsulation film has a second groove and a second sealing edge. The second sealing edge is distributed around the second groove on at least three sides. Wherein, the first sealing edge and the second sealing edge are connected to define a sealing edge area, the first groove and the second groove surround a receiving cavity, the sealing edge area includes a first sealing area and a second sealing area that are spaced apart, the first sealing area is located on the side of the second sealing area that is close to the receiving cavity, at least one of the first sealing area and the second sealing area has a first sub-sealing area and a second sub-sealing area, and in the first sealing area and the second sealing area, the first sub-sealing area is located on the side of the second sub-sealing area that is close to the receiving cavity; Along the first direction, the thickness of the first sub-seal area is greater than the thickness of the second sub-seal area.

2. The multiple package structure of claim 1, wherein, The multi-encapsulation structure includes a first side, a second side, a third side, and a fourth side connected in sequence. Along a second direction, the first side and the third side are arranged opposite to each other. Along a third direction, the second side and the fourth side are arranged opposite to each other. The first encapsulation film and the second encapsulation film are connected on the first side. The first sealing edge and the second sealing edge are connected on the second side, the third side, and the fourth side to form the sealing edge area. The first direction, the second direction, and the third direction are perpendicular to each other. The third side is used to bring out the electrode tab, and the first sub-seal area is located on at least one of the second side and the fourth side.

3. The multiple package structure of claim 2, wherein, Both the first sealing area and the second sealing area are provided with a first sub-sealing area and a second sub-sealing area; Within the first sealing area and the second sealing area, the first sub-sealing area is distributed around the accommodating cavity on the second side, the third side and the fourth side, and the second sub-sealing area is distributed around the first sub-sealing area on the second side, the third side and the fourth side.

4. The multiple package structure of claim 1, wherein, Along the direction away from the receiving cavity from the first sub-sealing area, the first sub-sealing area includes at least a guide section with a gradually decreasing cross-sectional area.

5. The multiple package structure of claim 2, wherein, In the boundary area between the second side and the third side, the sealing area is provided with a notch; And / or, in the boundary area between the third side and the fourth side, the sealing area is provided with the notch.

6. The multiple package structure of claim 1, wherein, The sealing area further includes a first interval area, which is located between the first sealing area and the second sealing area, and the first sealing edge and the second sealing edge abut against each other in the first interval area.

7. The multiple package structure of claim 6, wherein, The width of the first interval region located on either side of the accommodating cavity is a, where 0.1mm ≥ a ≥ 1.5mm.

8. The multiple package structure of claim 1, wherein, On either side of the accommodating cavity, the sum of the widths of the first sealing area and the second sealing area is b, and the width of the first sub-sealing area is c, where bc ≥ 1 mm.

9. The multiple package structure of claim 1, wherein, The multiple packaging structure further comprises a third sealing area and a second spacing area, the third sealing area is arranged in a spaced manner on a side of the second sealing area away from the accommodating cavity, and the second spacing area is located between the second sealing area and the third sealing area.

10. A battery, characterized by Comprise: an electric core; the multiple packaging structure according to any one of claims 1 to 9, wherein the electric core is located in the accommodating cavity.

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