Shell and battery

Abstract

In order to solve the problems that the packaging height is large and the energy density is not favorably improved in plastic riveting packaging of an existing hard-shell battery, the utility model provides a shell and a battery, the shell comprises a first shell and a second shell, the first shell is of a barrel-shaped structure with an opening in one end, and the second shell is of a barrel-shaped structure with an opening in the other end; the opening end of the first shell and the second shell are partially overlapped to form an overlapping area, accommodating cavities for accommodating battery cells are formed in the first shell and the second shell, and the overlapping area extends in the axial direction or the radial direction. According to the shell provided by the invention, the opening ends of the second shell and the first shell are partially overlapped to form the sealed connecting part, so that an elastic plastic part does not need to be added, the packaging height of the battery is not increased, waste in the height direction of the battery is not caused, and improvement of the energy density of the battery is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of shells, and in particular to a shell and a battery. Background Art

[0002] With the continuous advancement of technology in the fields of consumer electronics, wearables, micro devices, etc., the requirements for the energy density of lithium-ion batteries continue to increase. At the same time, since moisture has a great impact on the performance and service life of lithium-ion batteries, packaging technology is becoming more and more critical to the reliability and energy density of lithium-ion batteries. Typical lithium-ion batteries generally have three forms: hard shell cylindrical, hard shell square and soft pack batteries. The packaging of hard shell batteries generally adopts the method of placing elastic plastic parts between the pole and the cover plate, and compressing the plastic parts after riveting to form insulation and sealing between the positive and negative poles of the battery, or rolling grooves on the shell, placing plastic parts between the shell and the cover plate and then sealing to form an insulating seal. The packaging height of these two methods is generally greater than 5 mm, resulting in a waste of space in the height direction of the battery, which is not conducive to the improvement of energy density. Utility Model Content

[0003] The technical problem to be solved by the utility model is as follows: In view of the problem that the existing plastic riveted packaging of hard shell batteries has a large packaging height, which is not conducive to improving the energy density, the application provides a shell and a battery.

[0004] The present application provides a shell, including a first shell and a second shell, the first shell is a barrel-shaped structure with one end open, the open end of the first shell partially overlaps with the second shell to form an overlapping area, and the first shell and the second shell are provided with accommodating cavities for accommodating battery cells, and the overlapping area extends axially or radially.

[0005] Preferably, the first shell includes a first main body portion, and the second shell includes a second main body portion, the first main body portion is provided with a first thermoplastic resin layer toward the overlapping area, the second main body portion is provided with a second thermoplastic resin layer toward the overlapping area, and the second thermoplastic resin layer is heat-sealed to the first thermoplastic resin layer to form a sealed connection portion.

[0006] Preferably, a first adhesive layer is provided between the first main body and the first thermoplastic resin layer, and a second adhesive layer is provided between the second main body and the second thermoplastic resin layer.

[0007] Preferably, at least one third thermoplastic resin layer is further provided on the first main body in a direction toward the accommodating cavity, and one end of the first thermoplastic resin layer is connected to one end of one of the third thermoplastic resin layers;

[0008] At least one fourth thermoplastic resin layer is further disposed on the second main body in a direction away from the accommodating cavity, and one end of the second thermoplastic resin layer is connected to one end of one of the fourth thermoplastic resin layers.

[0009] Preferably, a third adhesive layer is further provided between the first main body and the third thermoplastic resin layer, and a fourth adhesive layer is further provided between the second main body and the fourth thermoplastic resin layer;

[0010] One end of the first adhesive layer is connected to one end of one of the third adhesive layers, and one end of the second adhesive layer is connected to one end of one of the fourth adhesive layers.

[0011] Preferably, at least one fifth adhesive layer is provided on the first main body in a direction away from the accommodating cavity, and a first heat-resistant resin layer is provided on the fifth adhesive layer in a direction away from the first main body;

[0012] At least one sixth adhesive layer is disposed on the second main body in a direction toward the accommodating cavity, and at least one insulating layer is disposed on the sixth adhesive layer in a direction away from the second main body;

[0013] A colored layer is disposed between the first heat-resistant resin layer and the fifth adhesive layer, and a matte layer is disposed on the first heat-resistant resin layer in a direction away from the colored layer.

[0014] Preferably, the first main body and the second main body are made of metal or alloy material;

[0015] The first main body is provided with a first internal electrical connection area in a direction facing the accommodating cavity, and the first main body is provided with a first external electrical connection area in a direction away from the accommodating cavity;

[0016] The second main body is provided with a second internal electrical connection area in a direction facing the accommodating cavity, and the second main body is provided with a second external electrical connection area in a direction away from the accommodating cavity.

[0017] Preferably, the second shell is a planar structure, and extension portions are provided in radial directions on both sides of the opening end of the first shell, and the extension portions overlap with the first shell portion to form the sealing connection portion.

[0018] Preferably, the first main body portion includes a first support member and a second support member, the second support member is a barrel-shaped structure with openings at both ends, one end of the second support member is welded to the outer edge of the first support member, and the extension portion is provided on a side of the second support member away from the first support member.

[0019] In a second aspect, the present application provides a battery, comprising the shell and pole core described above, wherein the pole core is arranged in the accommodating cavity.

[0020] Beneficial effects:

[0021] Compared with the prior art, the shell provided by the present application has a second shell and an open end portion that overlaps with the first shell to form a sealed connection portion. There is no need to add elastic plastic parts, the packaging height of the battery is not increased, and no waste in the height direction of the battery is caused, which is beneficial to the improvement of the battery energy density. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the housing structure of the housing-embodiment 1 provided in the present application;

[0023] Figure 2 This is a schematic diagram of the housing structure of the housing-embodiment 2 provided by the present application;

[0024] Figure 3 This is a schematic diagram of the shell structure of the shell-embodiment three provided by the present application;

[0025] Figure 4 This application provides a housing - a schematic diagram of the housing structure of Example 4;

[0026] Figure 5 yes Figure 4 A is an enlarged view of the middle image.

[0027] Among them, 1. first shell; 101. first main body; 1011. first support member; 1012. second support member; 102. first thermoplastic resin layer; 103. third thermoplastic resin layer; 104. first bonding layer; 105. third bonding layer; 106. fifth bonding layer; 107. first heat-resistant resin layer; 108. coloring layer; 109. matte layer; 110. first inner electrical connection area; 111. first outer electrical connection area; 2. second shell; 201. second main body; 202. second thermoplastic resin layer; 203. fourth thermoplastic resin layer; 204. second bonding layer; 205. fourth bonding layer; 206. sixth bonding layer; 207. insulating layer; 208. second inner electrical connection area; 209. second outer electrical connection area; 3. pole core. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0029] In order to illustrate the technical solution of the present utility model, specific embodiments are provided below for illustration.

[0030] Embodiment 1

[0031] like Figure 1 As shown, the present application provides a shell, including a first shell 1 and a second shell 2, the first shell 1 is a barrel-shaped structure with one end open, the open end of the first shell 1 partially overlaps with the second shell 2 to form an overlapping area, and the first shell 1 and the second shell 2 are provided with accommodating cavities for accommodating battery cells, and the overlapping area extends axially or radially.

[0032] Specifically, Figure 1 As shown, the first shell 1 is in the shape of a square structure with one end open. It is understandable that the first shell 1 can also be in the shape of a cup, a cylinder, a prism, etc. with one end open.

[0033] The opening end of the first shell 1 partially overlaps with the second shell 2 to form an overlapping area. The first shell 1 and the second shell 2 are provided with a receiving cavity for receiving a battery cell. Figure 1 As shown, the first shell 1 is a square structure with an open end, and the second shell 2 is also a square structure with an open end. The open end of the first shell 1 and the open end of the second shell 2 are assembled to form a accommodating cavity for accommodating the battery cell. At the same time, the partially overlapping area of ​​the first shell 1 and the second shell 2 forms a sealed connection portion to prevent battery leakage.

[0034] The overlapping area extends along the axial direction or radial direction specifically means that when the partially overlapping area of ​​the first shell 1 and the second shell 2 is located on both sides of the shell, the overlapping area is located on the side of the shell, and the overlapping area of ​​this structure can extend along the axial direction; when the partially overlapping area of ​​the first shell 1 and the second shell 2 is located at the top or bottom of the shell, the overlapping area is located at the top or bottom of the shell, and the overlapping area of ​​this structure can extend along the radial direction. Figure 1 As shown, the overlapping area is located at the side of the housing, and the overlapping area can extend in the axial direction.

[0035] In the shell provided in the present application, the second shell 2 partially overlaps with the open end of the first shell 1 to form an overlapping area, and there is no need to add elastic plastic parts, which does not increase the packaging height of the battery and does not cause waste in the height direction of the battery, which is beneficial to improving the energy density of the battery.

[0036] In the first embodiment, the cross-sectional shape of the sealing connection portion is square, annular or elliptical.

[0037] Specifically, when the sealing connection portion extends along the axial direction, the cross-sectional shape of the sealing connection portion is a square, and when the sealing connection portion extends along the radial direction, the cross-sectional shape of the sealing connection portion is an ellipse.

[0038] In the first embodiment, the first shell 1 is a barrel-shaped structure with one end open, and the second shell 2 is a barrel-shaped structure with a first opening.

[0039] like Figure 1 As shown, the width of the opening end of the first shell 1 is the same as the inner width of the first shell 1 , and the width of the opening end of the second shell 2 is the same as the inner width of the second shell 2 .

[0040] In some embodiments, the first shell 1 includes a first main body portion 101, and the second shell 2 includes a second main body portion 201. The first main body portion 101 is provided with a first thermoplastic resin layer 102 toward the overlapping area, and the second main body portion 201 is provided with a second thermoplastic resin layer 202 toward the overlapping area. The second thermoplastic resin layer 202 is heat-sealed to the first thermoplastic resin layer 102 to form a sealed connection portion.

[0041] Specifically, the sealed connection portion is formed by the overlapping portion of the first thermoplastic resin layer 102 and the second thermoplastic resin layer 202 through hot pressing and melting and softening, which can make the first shell 1 and the second shell 2 sealed and connected to prevent battery leakage, while not increasing the packaging height of the battery, not causing waste in the height direction of the battery, and is conducive to improving the battery energy density. Due to the insulation properties of the first thermoplastic resin layer 102 and the second thermoplastic resin layer 202, insulation between the positive and negative electrodes of the battery can be achieved.

[0042] In order to effectively prevent water vapor, oxygen, etc. outside the battery from entering the interior, the width or height of the sealed connection portion needs to be greater than 0.5 mm, preferably greater than 1.0 mm.

[0043] To ensure the reliability of the sealed connection, the heat sealing temperature needs to be higher than the softening temperature of the first thermoplastic resin layer 102 and the second thermoplastic resin layer 202 but lower than the softening temperature of the first heat-resistant resin layer 107; for example, the heat sealing temperature is 80~180°C, preferably 100~150°C.

[0044] In order to ensure the reliability of the sealed connection, it is necessary to apply appropriate pressure to the sealed connection during heat sealing to ensure that the softened first thermoplastic resin layer 102 and the second thermoplastic resin layer 202 are subjected to a certain pressure to achieve good bonding.

[0045] The thickness of the first thermoplastic resin layer 102 after compression or solidification is H1, and the thickness of the first thermoplastic resin layer 102 before softening is H2, and H1:H2 is (0.5-0.9):1; more preferably, H1:H2 is (0.65-0.85):1.

[0046] The thickness of the second thermoplastic resin layer 202 after compression or solidification is H3, and the thickness of the second thermoplastic resin layer 202 before softening is H4, and H3:H4 is (0.5-0.9):1; more preferably, H3:H4 is (0.65-0.85):1.

[0047] The second thermoplastic resin layer 202 will be used to encapsulate the shell and needs to be able to soften when heated, not peel off when immersed in electrolyte, and have excellent chemical resistance such as resistance to electrolyte immersion and corrosion and trace hydrofluoric acid corrosion. The material of the second thermoplastic resin layer 202 is not particularly limited.

[0048] In the first embodiment, the material of the second thermoplastic resin layer 202 and the first thermoplastic resin layer 102 is one of unstretched films of polyolefin, cyclic polyolefin, acid-modified polyolefin, acid-modified cyclic polyolefin or ionomer resin.

[0049] In the preferred embodiment 1, the second thermoplastic resin layer 202 and the first thermoplastic resin layer 102 are made of one of unstretched films of polyethylene, polypropylene, olefin copolymers, acid-modified polyethylene, acid-modified polypropylene, acid-modified olefin copolymers or ionomer resins.

[0050] More preferably, the material of the second thermoplastic resin layer 202 and the first thermoplastic resin layer 102 is one of unstretched films of polypropylene, maleic acid-modified polypropylene, ethylene acrylate copolymer, and ionomer resin.

[0051] In the first embodiment, the thickness of the second thermoplastic resin layer 202 and the first thermoplastic resin layer 102 are both 20 μm to 80 μm.

[0052] In the preferred embodiment 1, the thickness of the second thermoplastic resin layer 202 and the first thermoplastic resin layer 102 are both 30 μm to 50 μm.

[0053] More preferably, the second thermoplastic resin layer 202 and the first thermoplastic resin layer 102 have a thickness of 20-30 μm, 40-50 μm, 50-60 μm, 60-70 μm or 70-80 μm.

[0054] In the preferred embodiment 1, the second thermoplastic resin layer 202 and the first thermoplastic resin layer 102 are made of the same material and have the same thickness.

[0055] In the first embodiment, a first adhesive layer 104 is disposed between the first main body 101 and the first thermoplastic resin layer 102 , and a second adhesive layer 204 is disposed between the second main body 201 and the second thermoplastic resin layer 202 .

[0056] Specifically, the first adhesive layer 104 is a layer provided to firmly bond the first main body 101 to the first thermoplastic resin layer 102. The second adhesive layer 204 is a layer provided to firmly bond the second main body 201 to the second thermoplastic resin layer 202. The second adhesive layer 204 is formed of an adhesive that can firmly bond the second main body 201 to the second thermoplastic resin layer 202. Similarly, the first adhesive layer 104 is also formed of an adhesive that can firmly bond the first main body 101 to the first thermoplastic resin layer 102.

[0057] The adhesive used in the first adhesive layer 104 and the adhesive used in the second adhesive layer 204 are required to have excellent adhesion, electrolyte resistance and water vapor barrier properties.

[0058] In the first embodiment, the material of the second adhesive layer 204 and the first adhesive layer 104 are both one of polyurethane adhesive, acrylic adhesive, epoxy adhesive, polyolefin adhesive, elastomer adhesive, fluorine adhesive or acid-modified polypropylene adhesive.

[0059] In the preferred embodiment 1, the second adhesive layer 204 and the first adhesive layer 104 are both made of acrylic adhesive or polyolefin adhesive.

[0060] Furthermore, the second adhesive layer 204 and the first adhesive layer 104 are both made of carboxylic acid-modified polyolefin resin. Furthermore, the second adhesive layer 204 and the first adhesive layer 104 are both made of carboxylic acid-modified polypropylene.

[0061] In the first embodiment, the thickness of the second adhesive layer 204 and the first adhesive layer 104 are both 1-5 μm.

[0062] The thickness of the second adhesive layer 204 and the first adhesive layer 104 may both be 1 μm, 2 μm, 3 μm, 4 μm or 5 μm.

[0063] In the first embodiment, the first main body 101 and the second main body 201 are made of metal or alloy material.

[0064] Specifically, the second main body 201 needs to prevent the intrusion of oxygen and moisture. At the same time, in order to ensure the smooth progress of heat sealing, it must have sufficient strength. At the same time, in order to have better processability during the stamping process, the second main body 201 must have sufficient ductility. In addition, since the second main body 201 needs to be connected to the positive or negative electrode of the pole core 3 as an electrical connection material, the metal material selected for the second main body 201 must be able to remain stable within its working potential range and at the same time be able to withstand long-term corrosion by the electrolyte.

[0065] When the second main body 201 is connected to the positive electrode of the pole core 3, the metal or alloy material used includes but is not limited to stainless steel, titanium alloy, high-strength aluminum alloy, nano-twin steel, high-entropy alloy, Inconel718 alloy, nano-bainite steel, nano-structured molybdenum alloy, duplex alloy, eutectic high-entropy alloy, one of high-strength, high-toughness and low-density steel, preferably high-strength and high-toughness stainless steel.

[0066] To ensure that the above performance requirements are met, the second body 201 can also be made of multiple layers of metal or alloy materials, such as high-strength and high-toughness stainless steel plated with aluminum. The aluminum plating method can be vacuum evaporation, magnetron sputtering, chemical plating, hot plating, etc.

[0067] When the second main body 201 is connected to the negative electrode of the pole core 3, the metal or alloy material used includes but is not limited to stainless steel, titanium alloy, nano-twin steel, high entropy alloy, Inconel 718 alloy, nano-bainite steel, nano-structured molybdenum alloy, duplex alloy, eutectic high entropy alloy, one of high-strength, high-toughness and low-density steel, preferably high-strength and high-toughness stainless steel.

[0068] The thickness of the second body 201 is preferably 20 μm to 100 μm. By setting it to 20 μm or more, pores can be prevented from being generated during rolling to manufacture the metal foil, and by setting it to 100 μm or less, stress during bulging, drawing or punching can be reduced, thereby improving workability.

[0069] The first main body 101 needs to prevent the intrusion of oxygen and moisture. At the same time, in order to ensure the smooth heat sealing and processability during molding, the material must have sufficient toughness. At the same time, since the first main body 101 needs to be connected to one pole of the battery cell assembly as an electrical connection material, the first main body 101 must be able to remain stable within the working potential range of the electrode connected to it, and at the same time be able to withstand long-term corrosion from the electrolyte.

[0070] When the first main body 101 is connected to the positive electrode of the pole core 3, the metal or alloy material used includes but is not limited to stainless steel, titanium alloy, high-strength aluminum alloy, nano-twin steel, high-entropy alloy, Inconel 718 alloy, nano-bainite steel, nano-structured molybdenum alloy, duplex alloy, eutectic high-entropy alloy, one of high-strength, high-toughness and low-density steel, preferably high-strength and high-toughness stainless steel or aluminum alloy.

[0071] At the same time, to ensure that the above performance requirements can be met, the first main body 101 can also be made of multiple layers of metal or alloy materials, such as high-strength and high-toughness stainless steel plated with aluminum. The aluminum plating method can be vacuum evaporation, magnetron sputtering, chemical plating, hot plating, etc.

[0072] When the first main body 101 is connected to the negative electrode of the pole core 3, the metal or alloy material used includes but is not limited to stainless steel, titanium alloy, nano-twin steel, high entropy alloy, Inconel 718 alloy, nano-bainite steel, nano-structured molybdenum alloy, duplex alloy, eutectic high entropy alloy, one of high-strength, high-toughness and low-density steel, preferably high-strength and high-toughness stainless steel.

[0073] The first main body 101 may be made of the same material as or different from the second main body 201. When the same material is used, the thickness may be appropriately reduced to improve the processability.

[0074] In the first embodiment, the thickness of the first main body 101 is 10 μm to 80 μm.

[0075] In embodiment 1, the first main body 101 is provided with a first internal electrical connection area in the direction toward the accommodating cavity, and the first main body 101 is provided with a first external electrical connection area in the direction away from the accommodating cavity; the second main body 201 is provided with a second internal electrical connection area in the direction toward the accommodating cavity, and the second main body 201 is provided with a second external electrical connection area in the direction away from the accommodating cavity.

[0076] Specifically, in the first embodiment, the area of ​​the first main body 101 where the first thermoplastic resin layer 102 is not provided and the direction toward the accommodating cavity is the first internal electrical connection area, and the direction of the first main body 101 away from the accommodating cavity is the first external electrical connection area; this is because the material of the first main body 101 is metal or alloy material, which is conductive itself and can be electrically connected to the positive or negative electrode of the pole core 3, and can also be electrically connected to an external power supply.

[0077] The area of ​​the second main body 201 where the second thermoplastic resin layer 202 is not provided and the direction away from the accommodating cavity is the second external electrical connection area, and the direction of the second main body 201 toward the accommodating cavity is the second internal electrical connection area. This is because the material of the second main body 201 is metal or alloy material, which is conductive itself and can be electrically connected to the positive or negative pole of the pole core 3, and can also be electrically connected to an external power supply.

[0078] Embodiment 2

[0079] Most of the structures of the second embodiment are the same as those of the first embodiment, except that the structures of the first shell 1 and the second shell 2 are different, as described below.

[0080] In the second embodiment, the second shell 2 is a planar structure, and extensions are provided in the radial direction on both sides of the opening end of the first shell 1, and the extensions partially overlap with the first shell 1 to form an overlapping area.

[0081] like Figure 2As shown, in embodiment 2, the second shell 2 is a planar structure, the first shell 1 is a barrel-shaped structure with one end open, and extension portions are provided in the radial direction on both sides of the open end of the first shell 1, and the extension portions partially overlap with the second shell 2 to form an overlapping area.

[0082] exist Figure 2 In the embodiment, the second shell 2 is arranged inside the first shell 1. It should be noted that the second shell 2 can also be arranged outside the first shell 1 to increase the space inside the shell.

[0083] In the second embodiment, the sealing connection part is arranged on the top of the shell, and the cross-sectional structure of the sealing connection part is annular or elliptical.

[0084] In the second embodiment, the first adhesive layer 104 and the first thermoplastic resin layer 102 are provided at the opening end and the extension portion of the first main body 101, and the first adhesive layer 104 and the first thermoplastic resin layer 102 at the opening end of the first main body 101 extend toward the direction close to the accommodating cavity, mainly to achieve better sealing, seal the first shell 1 and the second shell 2, and prevent battery leakage.

[0085] In the second embodiment, the width of the extension portion in the first direction is greater than 0.5 mm.

[0086] More preferably, the width of the extension portion in the first direction is greater than 1.0 mm. Even more preferably, the width of the extension portion in the first direction is greater than 1.5 mm.

[0087] Specifically, Figure 2 As shown, the first direction in the present application refers to the y direction, the radial direction refers to the x direction, and the axial direction refers to the z direction.

[0088] Embodiment 3

[0089] The structure of the third embodiment is similar to that of the second embodiment, except that the structure of the first body is different from that of the second embodiment, as described below.

[0090] like Figure 3 As shown, in embodiment three, the first main body portion 101 includes a first support member 1011 and a second support member 1012, the second support member 1012 is a barrel-shaped structure with openings at both ends, one end of the second support member 1012 is welded to the outer edge of the first support member 1011, and the extension portion is provided on the side of the second support member 1012 facing away from the first support member 1011.

[0091] Specifically, in the third embodiment, the first main body 101 includes a first support member 1011 and a second support member 1012. An extension portion is provided on the side of the second support member 1012 away from the first support member 1011. The extension portion overlaps with a portion of the first shell 1 to form the overlapping area, which is used for sealing the first shell 1 and the second shell 2 to prevent battery leakage. The first support member 1011 and the second support member 1012 are made of metal or alloy, so the first support member 1011 and the second support member 1012 are connected together by laser welding.

[0092] It should be noted that for the shell structure of the third embodiment, there are two assembly methods when assembling the battery. The first assembly method is: first weld the first support member 1011 and the second support member 1012, place the pole core 3 in the first shell 1, inject the electrolyte, and then place the second shell 2 in the first shell 1 or place the second shell 2 outside the first shell 1. More preferably, place the second shell 2 in the first shell 1; at the same time, the first thermoplastic resin layer 102 of the first shell 1 and the second thermoplastic resin layer 202 of the second shell 2 are softened by hot pressing and melting, so that the first shell 1 and the second shell 2 are sealed and connected.

[0093] The second assembly method is: first place the second shell 2 in the extension part of the second support member 1012, and at the same time, soften the first thermoplastic resin layer 102 and the second thermoplastic resin layer 202 of the second shell 2 by hot pressing and melting, and seal the two second support members 1012 and the second shell 2, and then place the pole core 3 in the accommodating cavity, inject electrolyte, and seal the second support member 1012 and the first support member 1011 by laser welding.

[0094] Embodiment 4

[0095] Embodiment 4 includes the technical solution of embodiment 1, and embodiment 4 adds the following technical features based on embodiment 1.

[0096] In the fourth embodiment, at least one third thermoplastic resin layer 103 is further provided on the first main body 101 in the direction toward the accommodation cavity, and one end of the first thermoplastic resin layer 102 is connected to one end of one of the third thermoplastic resin layers 103;

[0097] At least one fourth thermoplastic resin layer 203 is further disposed on the second main body 201 in a direction away from the accommodation cavity, and one end of the second thermoplastic resin layer 202 is connected to one end of one of the fourth thermoplastic resin layers 203 .

[0098] Specifically, Figure 4-5As shown, because internal and external electrical connection areas are also provided in the battery, at least one third thermoplastic resin layer 103 is provided in the direction of the first main body 101 toward the accommodating cavity, and at least one fourth thermoplastic resin layer 203 is provided in the direction of the second main body 201 away from the accommodating cavity, thereby ensuring that the first main body 101 and the second main body 201 have an external leakage area, thereby being able to form internal and external electrical connection areas.

[0099] For the first inner electrical connection area 110, the first outer electrical connection area 111, the second inner electrical connection area 208, and the second outer electrical connection area 209, the first inner electrical connection area 110, the first outer electrical connection area 111, the second inner electrical connection area 208, and the second outer electrical connection area 209 can be directly reserved during the processing of the first shell 1 and the second shell 2; or the adhesive layer at the relevant position is directly removed after the first shell 1 and the second shell 2 are processed and formed; the removal method can be a mechanical method, a laser method, a chemical method or a combination thereof.

[0100] It should be noted that the third thermoplastic resin layer 103 has the same material and thickness as the first thermoplastic resin layer 102 and has the same function as the first thermoplastic resin layer 102. The fourth thermoplastic resin layer 203 has the same material and thickness as the second thermoplastic resin layer 202 and has the same function as the second thermoplastic resin layer.

[0101] It should be noted that if the battery housing requires multiple first inner electrical connection areas 110, first outer electrical connection areas 111, second inner electrical connection areas 208, and second outer electrical connection areas 209, the number of corresponding third thermoplastic resin layers 103 and fourth thermoplastic resin layers 203 will also increase accordingly.

[0102] In the fourth embodiment, a third adhesive layer 105 is further provided between the first main body 101 and the third thermoplastic resin layer 103, and a fourth adhesive layer 205 is further provided between the second main body 201 and the fourth thermoplastic resin layer 203;

[0103] One end of the first adhesive layer 104 is connected to one end of one of the third adhesive layers 105 , and one end of the second adhesive layer 204 is connected to one end of one of the fourth adhesive layers 205 .

[0104] Specifically, the material, function and thickness of the third adhesive layer 105 are the same as those of the first adhesive layer 104 , and the material, function and thickness of the fourth adhesive layer 205 are also the same as those of the second adhesive layer 204 .

[0105] It should be noted that, if a plurality of third thermoplastic resin layers 103 are disposed on the first main body 101, a corresponding third adhesive layer 105 is disposed between the first main body 101 and each third thermoplastic resin layer 103. Similarly, if a plurality of fourth thermoplastic resin layers 203 are disposed on the second main body 201, a corresponding fourth adhesive layer 205 is disposed between the second main body 201 and each fourth thermoplastic resin layer 203.

[0106] Specifically, if the first inner electrical connection area 110 is not provided between the first thermoplastic resin layer 102 and the third thermoplastic resin layer 103, one end of the first thermoplastic resin layer 102 is preferably connected to one end of one of the third thermoplastic resin layers 103. Similarly, if the second outer electrical connection area 209 is not provided between the second thermoplastic resin layer 202 and the fourth thermoplastic resin layer 203, one end of the second thermoplastic resin layer 202 is preferably connected to one end of one of the fourth thermoplastic resin layers 203.

[0107] In the fourth embodiment, at least one fifth adhesive layer 106 is disposed on the first main body 101 in a direction away from the accommodation cavity, and a first heat-resistant resin layer 107 is disposed on the fifth adhesive layer 106 in a direction away from the first main body 101;

[0108] At least one sixth adhesive layer 206 is disposed on the second main body portion 201 in a direction facing the accommodation cavity, and at least one insulating layer 207 is disposed on the sixth adhesive layer 206 in a direction away from the second main body portion 201 .

[0109] Specifically, the sixth bonding layer 206 located inside the second main body 201 is used to firmly bond the second main body 201 to the insulating layer 207. The adhesive selected for the sixth bonding layer 206 needs to have excellent bonding properties, electrolyte resistance and water vapor barrier properties. The selected adhesive is not particularly limited, and can be a two-liquid curing adhesive or a single-liquid curing adhesive. The bonding mechanism is also not particularly limited, and can be any one of a chemical reaction type, a solvent volatilization type, a hot melt type, a hot pressing type, etc.

[0110] It should be noted that the adhesive used in the sixth adhesive layer 206 may be the same as or different from that used in the second adhesive layer 204 and the fourth adhesive layer 205. In order to reduce the thickness and weight of the packaging material, the thickness of the sixth adhesive layer 206 is preferably 1-5 um.

[0111] The insulating layer 207 is used to prevent a short circuit between the pole core 3 and the second main body 201. It needs to have good insulation, not be separated from the adhesive layer when immersed in the electrolyte, and have excellent chemical resistance such as resistance to electrolyte immersion and corrosion and trace hydrofluoric acid corrosion. The material selected for the insulating layer 207 is not particularly limited, and the same material as the second thermoplastic resin layer 202 can be used, or a different material can be used.

[0112] The thickness of the insulating layer 207 is 5 μm to 50 μm, and preferably the thickness of the insulating layer 207 is 10 μm to 30 μm.

[0113] At least one sixth adhesive layer 206 and an insulating layer 207 are disposed in the direction of the second main body 201 toward the accommodating cavity, and a second inner electrical connection area 208 can be disposed between two adjacent sixth adhesive layers 206 and insulating layers 207 .

[0114] The first heat-resistant resin layer 107 is an outer layer when used as the first main body 101. It is a resin film with excellent heat resistance, formability, insulation, etc., and a heat-resistant resin that does not melt at the heat sealing temperature is used. The heat-resistant resin selected for the first heat-resistant resin layer 107 is preferably a heat-resistant resin with a melting point higher than that of a thermoplastic resin by more than 10°C, and particularly preferably a heat-resistant resin with a melting point higher than that of a thermoplastic resin by more than 20°C. For example, a stretched film such as a polyamide film or a polyester film, and particularly preferably a biaxially stretched polyamide film, a biaxially stretched polybutylene terephthalate (PBT) film, a biaxially stretched polyethylene terephthalate (PET) film, or a biaxially stretched polyethylene naphthalate (PEN) film. For example, a nylon 6 film, a nylon 6,6 film, a nylon MXD film, etc. It should be noted that the first heat-resistant resin layer 107 may be formed of a single layer or multiple layers. For example, the multiple layers may be a multilayer film formed of PET film / polyamide film.

[0115] The thickness of the first heat-resistant resin layer 107 is 9 μm to 50 μm.

[0116] The fifth adhesive layer 106 is a bonding layer between the first main body 101 and the first heat-resistant resin layer 107 , and the adhesive used for the fifth adhesive layer 106 is not particularly limited.

[0117] The fifth adhesive layer 106 includes an adhesive layer formed by a two-liquid curing adhesive. The two-liquid curing adhesive is composed of a first liquid and a second liquid (curing agent) containing an isocyanate, and the first liquid contains one or more polyols selected from polyurethane polyols, polyester polyols, polyether polyols, and polyester polyurethane polyols. More preferably, the first liquid contains one or more polyols selected from polyester polyols and polyester polyurethane polyols.

[0118] The thickness of the fifth adhesive layer 106 is 1-5 um.

[0119] In the fourth embodiment, a coloring layer 108 is disposed between the first heat-resistant resin layer 107 and the fifth adhesive layer, and a matte layer 109 is disposed on the first heat-resistant resin layer 107 in a direction away from the coloring layer 108 .

[0120] For the purpose of beautifying the appearance of the battery and printing, a colored layer 108 can also be set on the inner side of the first heat-resistant resin layer 107 in the first shell 1, and a matte layer 109 can be set on the outer side. The colored layer 108 is composed of a colored composition containing a resin binder and a colorant. The matte layer 109 is a surface layer provided for imparting good sliding properties to the surface of the first shell 1 and improving the formability. By providing the matte layer 109, it is not easy to slide between the first heat-resistant resin layer 107 and the colored layer 108 during molding and heat sealing, and the first heat-resistant resin layer 107 is not easy to peel off from the coloring. The matte coating is a layer formed by dispersing a resin composition containing inorganic particles in a heat-resistant resin component. Among them, the heat-resistant resin includes acrylic resin, epoxy resin, polyester resin, polyurethane resin, polyolefin resin, fluorine resin, phenoxy resin, etc., preferably a fluorine resin based on tetrafluoroethylene or fluoroethylene-vinyl ether. The inorganic fine particles include silicon dioxide, aluminum oxide, calcium oxide, calcium carbonate, calcium sulfate, calcium silicate and the like, among which silicon dioxide is preferably used.

[0121] The thickness of the coloring layer 108 is 0.5-5 um, and more preferably 1-3 um.

[0122] The thickness of the matte layer 109 (thickness after curing) is 0.5 μm to 5 μm, and more preferably 1 μm to 3 μm.

[0123] In the fourth embodiment, the first internal electrical connection area is disposed between the two third bonding layers 105; the first external electrical connection area is disposed between the two fifth bonding layers 106;

[0124] The second internal electrical connection region is disposed between the two sixth bonding layers 206 , and the second external electrical connection region is disposed between the two fourth bonding layers 205 .

[0125] Specifically, Figure 4As shown, a first internal electrical connection area is provided in the direction of the first main body 101 toward the accommodating cavity, and the first internal electrical connection area is provided between two third adhesive layers 105. The first internal electrical connection area is used to connect to the positive or negative electrode of the pole core 3, and the connection method is laser welding. A first external electrical connection area is provided in the direction of the first main body 101 away from the accommodating cavity, and the first external electrical connection area is provided between two fifth adhesive layers 106. The first external electrical connection area is used to connect to an external power source.

[0126] A second internal electrical connection area is provided in the direction of the second main body 201 toward the accommodating cavity, and the second internal electrical connection area is provided between the two sixth bonding layers 206. The second internal electrical connection area is used to connect to the positive or negative electrode of the pole core 3, and the connection method is laser welding. A second external electrical connection area is provided in the direction of the second main body 201 away from the accommodating cavity, and the second external electrical connection area is provided between the two fourth bonding layers 205. The second external electrical connection area is used to connect to an external power source.

[0127] In a second aspect, the present application provides a battery, comprising the shell and pole core 3 as described above, wherein the pole core 3 is disposed in the accommodating cavity.

[0128] like Figures 1 to 5 As shown, in the accommodation cavity formed by assembling the first shell 1 and the second shell 2, the pole core 3 is arranged in the accommodation cavity. The battery provided by the present application does not need to add elastic plastic parts when assembling the shell, does not increase the packaging height of the battery, does not cause waste in the height direction of the battery, and is conducive to improving the energy density of the battery.

[0129] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A housing, characterized in that: The device comprises a first shell and a second shell, wherein the first shell is a barrel-shaped structure with one end open, the open end of the first shell partially overlaps with the second shell to form an overlapping area, and the first shell and the second shell are provided with accommodating cavities for accommodating battery cells, and the overlapping area extends in an axial direction or a radial direction; The first shell includes a first main body, and the second shell includes a second main body. The first main body is provided with a first thermoplastic resin layer toward the overlapping area, and the second main body is provided with a second thermoplastic resin layer toward the overlapping area. The second thermoplastic resin layer is heat-sealed to the first thermoplastic resin layer to form a sealed connection.

2. The housing according to claim 1, characterized in that A first adhesive layer is disposed between the first main body and the first thermoplastic resin layer, and a second adhesive layer is disposed between the second main body and the second thermoplastic resin layer.

3. The housing according to claim 2, characterized in that: At least one third thermoplastic resin layer is further provided on the first main body in a direction toward the accommodating cavity, and one end of the first thermoplastic resin layer is connected to one end of one of the third thermoplastic resin layers; At least one fourth thermoplastic resin layer is further disposed on the second main body in a direction away from the accommodating cavity, and one end of the second thermoplastic resin layer is connected to one end of one of the fourth thermoplastic resin layers.

4. The housing according to claim 3, characterized in that: A third adhesive layer is further provided between the first main body and the third thermoplastic resin layer, and a fourth adhesive layer is further provided between the second main body and the fourth thermoplastic resin layer; One end of the first adhesive layer is connected to one end of one of the third adhesive layers, and one end of the second adhesive layer is connected to one end of one of the fourth adhesive layers.

5. The housing according to claim 3, characterized in that: At least one fifth adhesive layer is disposed on the first main body in a direction away from the accommodation cavity, and a first heat-resistant resin layer is disposed on the fifth adhesive layer in a direction away from the first main body; At least one sixth adhesive layer is disposed on the second main body in a direction toward the accommodating cavity, and at least one insulating layer is disposed on the sixth adhesive layer in a direction away from the second main body; A colored layer is disposed between the first heat-resistant resin layer and the fifth adhesive layer, and a matte layer is disposed on the first heat-resistant resin layer in a direction away from the colored layer.

6. The housing according to claim 1, characterized in that The first main body and the second main body are made of metal or alloy; The first main body is provided with a first internal electrical connection area in a direction facing the accommodating cavity, and the first main body is provided with a first external electrical connection area in a direction away from the accommodating cavity; The second main body is provided with a second internal electrical connection area in a direction facing the accommodating cavity, and the second main body is provided with a second external electrical connection area in a direction away from the accommodating cavity.

7. The housing according to claim 1, characterized in that The second shell is a planar structure, and extension portions are provided in radial directions on both sides of the opening end of the first shell. The extension portions overlap with a portion of the first shell to form the sealing connection portion.

8. The housing according to claim 7, characterized in that The first main body includes a first support member and a second support member, the second support member is a barrel-shaped structure with openings at both ends, one end of the second support member is welded to the outer edge of the first support member, and the extension portion is provided on a side of the second support member away from the first support member.

9. A battery, characterized in that: It comprises the shell and pole core as described in any one of claims 1 to 8, and the pole core is arranged in the accommodating cavity.

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