Battery device and electric device

Abstract

The utility model provides a battery device and a power utilization device, and belongs to the technical field of batteries. The battery device comprises a shell, an electrode assembly and an end cover assembly, the shell is provided with an opening; the electrode assembly is arranged in the shell; the end cover assembly comprises a top cover, a first plastic part and a pole, the top cover covers the opening of the shell, the first plastic part is arranged on the side, away from the electrode assembly, of the top cover, and the pole penetrates through the top cover and the first plastic part; at least part of the surface of the first plastic part is provided with an insulating layer, and the heat-resistant temperature of the insulating layer is higher than that of the first plastic part. The battery device provided by the utility model has more excellent insulation performance in a high-temperature environment, so that the problem of thermal runaway caused by insulation failure of the battery device can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery device and a power utilization device. BACKGROUND

[0002] The battery may cause internal short circuit under mechanical abuse, overcharge abuse and the like, leading to uncontrollable heat generation, thereby affecting the reliability of the battery product. CONTENT

[0003] In view of the above problems, the present application provides a battery device and a power utilization device, aiming to improve the reliability of the battery device.

[0004] In a first aspect, the present application provides a battery device, comprising a shell, an electrode assembly and a cover assembly; the shell is provided with an opening; the electrode assembly is arranged in the shell; the cover assembly comprises a top cover, a first plastic part and a pole, the top cover is arranged at the opening of the shell, the first plastic part is arranged on the side of the top cover away from the electrode assembly, and the pole is arranged through the top cover and the first plastic part; at least part of the surface of the first plastic part is provided with an insulating layer, and the heat-resistant temperature of the insulating layer is greater than the heat-resistant temperature of the first plastic part.

[0005] In the technical scheme of the present application, the first plastic part is used to insulate and separate the top cover and the pole. When the insulating layer with a heat-resistant temperature greater than that of the first plastic part is arranged on at least part of the surface of the first plastic part, the insulating layer can maintain good insulation performance in a high-temperature environment, thereby helping to improve the insulation stability of the first plastic part and reducing the risk of short circuit caused by the lapping of the top cover and the pole. Therefore, the battery device of the present application has more excellent insulation performance in a high-temperature environment, thereby reducing the problem of thermal runaway caused by insulation failure of the battery device.

[0006] In some embodiments, the side of the first plastic part facing the top cover and the side of the first plastic part away from the top cover are both provided with the insulating layer.

[0007] In the technical scheme of the present application, the insulating layer on the side of the first plastic part facing the top cover can reduce the problem of thermal melting and carbonization of the first plastic part in a high-temperature environment, and the insulating layer on the side of the first plastic part away from the top cover can further avoid the contact and short circuit between the pole and the top cover.

[0008] In some embodiments, the thickness of the insulating layer is 30-300 μm.

[0009] In the technical scheme of the present application, when the thickness of the insulating layer is between 30 μm and 300 μm, it helps to improve the heat insulation performance of the insulating layer, thereby further improving the insulation stability of the first plastic part.

[0010] In some embodiments, the end cover assembly comprises a second plastic member, the second plastic member is arranged between the top cover and the electrode assembly, and at least a part of a surface of the second plastic member is provided with the insulating layer.

[0011] In the technical solution of the embodiments of the present application, the second plastic member is arranged between the top cover and the electrode assembly to play an electrically insulating role. When the insulating layer is arranged on at least a part of the surface of the second plastic member, the temperature resistance of the second plastic member as a whole is improved, and the problem of insulation failure caused by melting of the second plastic member is reduced, thereby further reducing the risk of thermal runaway of the battery device.

[0012] In some embodiments, the second plastic member is provided with the insulating layer on at least a surface on a side facing the electrode assembly.

[0013] In the technical solution of the embodiments of the present application, the second plastic member is used for insulating and blocking the electrode assembly and the top cover. When the insulating layer is arranged on the surface of the second plastic member on a side facing the electrode assembly, the risk of thermal melting of the second plastic member is reduced, thereby reducing the problem of internal short circuit caused by direct contact between the electrode assembly and the top cover.

[0014] In some embodiments, the pole post comprises a bottom disc part and a post body part connected to the bottom disc part, the bottom disc part is arranged between the top cover and the electrode assembly, the post body part is arranged in the top cover and the first plastic member, and the bottom disc part is provided with the insulating layer on a surface on a side facing the top cover.

[0015] In the technical solution of the embodiments of the present application, the upper surface of the bottom disc part of the pole post is provided with the insulating layer, which can further reduce the problem of short circuit caused by contact between the electrode assembly and the top cover when the second plastic member fails due to thermal melting.

[0016] In some embodiments, the insulating layer comprises at least one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified organic silicone resin layer, a modified epoxy resin layer, a fluorine-containing polymer layer, and a ceramic material layer.

[0017] In the technical solution of the embodiments of the present application, the above-mentioned coating layers all have high heat resistance and can maintain their structural stability for a long time at high temperature.

[0018] In some embodiments, the modified epoxy resin layer comprises one of a phenolic modified epoxy resin layer, a silicone modified epoxy resin layer; and / or, the modified silicone resin layer comprises one of an alkyd modified silicone resin layer, an acrylic modified silicone resin layer, a polyurethane modified silicone resin layer; and / or, the fluoropolymer layer comprises one of a polytetrafluoroethylene layer, a fluorinated ethylene propylene copolymer layer, a polyvinylidene fluoride layer, an ethylene-tetrafluoroethylene copolymer layer; and / or, the ceramic material layer comprises one of an aluminum oxide layer, a silicon oxide layer, a magnesium aluminum spinel layer, a yttrium oxide layer.

[0019] In some embodiments, the insulating layer comprises a first coating layer and a second coating layer, the first coating layer comprises one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified silicone resin layer, a modified epoxy resin layer, the second coating layer comprises one of a fluoropolymer layer, a ceramic material layer; the thickness ratio of the first coating layer, the second coating layer is (6-9):(1-4).

[0020] In some embodiments, the thickness of the first coating layer is 18 μm-270 μm; and / or, the thickness of the second coating layer is 3 μm-120 μm.

[0021] In some embodiments, the insulating layer comprises a first coating layer, a second coating layer and a third coating layer, the first coating layer comprises one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, the second coating layer comprises one of a modified silicone resin layer, a modified epoxy resin layer, the third coating layer comprises one of a fluoropolymer layer, a ceramic material layer; the thickness ratio of the first coating layer, the second coating layer, the third coating layer is (4-6):(3-5):(1-3); or, the first coating layer comprises one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified silicone resin layer, a modified epoxy resin layer, the second coating layer comprises a fluoropolymer layer, the third coating layer comprises a ceramic material layer, the thickness ratio of the first coating layer, the second coating layer, the third coating layer is (5-9):(0.5-3):(0.5-2).

[0022] In some embodiments, the thickness of the first coating layer is 12 μm-270 μm; and / or, the thickness of the second coating layer is 1.5 μm-150 μm; and / or, the thickness of the third coating layer is 1.5 μm-90 μm.

[0023] In some embodiments, the insulating layer comprises a first coating layer, a second coating layer, a third coating layer and a fourth coating layer, the first coating layer comprises one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, the second coating layer comprises one of a modified silicone resin layer, a modified epoxy resin layer, the third coating layer comprises a fluoropolymer layer, and the fourth coating layer comprises a ceramic material layer; the thickness ratio of the first coating layer, the second coating layer, the third coating layer and the fourth coating layer is (4-5):(3-4):(0.5-2):(0.5-2).

[0024] In some embodiments, the thickness of the first coating layer is 12-150 microns; and / or, the thickness of the second coating layer is 9-120 microns; and / or, the thickness of the third coating layer is 1.5-60 microns; and / or, the thickness of the fourth coating layer is 1.5-60 microns.

[0025] In the technical scheme of the embodiments of the present application, at least two different insulating layers are combined to further improve the high-temperature resistance and the insulation stability of the first plastic part.

[0026] In some embodiments, a groove is formed on the side surface of the top cover away from the electrode assembly, and the first plastic part is embedded in the groove.

[0027] In the technical scheme of the embodiments of the present application, embedding the first plastic part in the groove on the top surface of the top cover can limit the insulating sealing ring of the column part of the pole.

[0028] In some embodiments, the shell comprises one of a stainless steel shell, an aluminum shell, an aluminum alloy shell, a copper shell, and an iron shell.

[0029] In a second aspect, the present application provides a power consumption device comprising the battery device of any one of the above.

[0030] The above description is only a summary of the technical scheme of the present application, in order to more clearly understand the technical means of the present application, and to implement the content of the specification, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 The structure of the vehicle in some embodiments of the present application is shown in the figure;

[0032] Figure 2 The exploded structure of the battery device in some embodiments of the present application is shown in the figure;

[0033] Figure 3 The exploded structure of the battery monomer in some embodiments of the present application is shown in the figure;

[0034] Figure 4 exploded view of the end cap assembly in some embodiments of the present application;

[0035] Figure 5 cross-sectional view of the first plastic part in some embodiments of the present application;

[0036] Figure 6 cross-sectional view of the insulation layer in some embodiments of the present application;

[0037] Figure 7 cross-sectional view of the insulation layer in some embodiments of the present application;

[0038] Figure 8 cross-sectional view of the insulation layer in some embodiments of the present application.

[0039] BRIEF DESCRIPTION OF DRAWINGS

[0040] vehicle 1000;

[0041] battery device 100, controller 200, motor 300;

[0042] box 10, first part 11, second part 12;

[0043] battery cell 20, end cap assembly 21, top cover 211, groove 2111, first plastic part 212, pole 213, chassis part 2131, column part 2132, insulation layer 214, first coating layer 2141, second coating layer 2142, third coating layer 2143, fourth coating layer 2144, riveting block 215, sealing ring 216, second plastic part 217, shell 22, electrode assembly 23. DETAILED DESCRIPTION

[0044] The following examples are for the purpose of more specifically setting forth the technical solutions of the present application, and thus are only for the purpose of illustration, and cannot be used to limit the protection scope of the present application.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the specification herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application; the terms "comprising" and "having," and any variations thereof, as used herein are intended to cover a non-exclusive inclusion.

[0046] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly and specifically limited.

[0047] Reference herein to "embodiments" means that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0048] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after it.

[0049] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces). The term "at least one" means one or more.

[0050] A plastic part is generally provided in a battery device to play an insulation protection role, such as a plastic part provided at a top cover to prevent thermal runaway caused by short circuit of overlapped key components on the top cover. However, when the battery device is overcharged (such as overcharge test), some battery devices such as steel shell battery cells may cause gas and heat accumulation due to late or poor valve opening, thereby causing the problem of melting of the plastic part at high temperature and insulation failure, and further causing short circuit of the pole and the top cover, thereby causing fire and other problems.

[0051] Based on the above problems, the present application provides a battery device, at least part of the surface of the plastic part is provided with an insulation layer, and the heat resistance temperature of the insulation layer is greater than the melting point of the plastic part.

[0052] In such a battery device, the insulation layer can maintain good insulation performance in a high temperature environment, thereby helping to improve the insulation stability of the plastic part and reduce the risk of short circuit caused by insulation failure.

[0053] The battery device disclosed in the embodiments of the present application can be used in, but is not limited to, an electric device such as a vehicle, a ship, an aircraft, etc. The power supply system of the electric device can also be composed of the battery device disclosed in the present application.

[0054] Embodiments of the present application provide a power consumption device using a battery device as a power supply, which can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, an electric car, an electric vehicle, a ship, a spacecraft, etc. Among them, the electric toy can include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, an electric plane toy, etc., and the spacecraft can include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0055] The following embodiments are described for convenience with a power consumption device of an embodiment of the present application as an example of a vehicle 1000.

[0056] Referring to Figure 1 The vehicle 1000 can be a fuel car, a gas car, or a new energy car, and the new energy car can be a pure electric car, a hybrid car, or a range extended car, etc. The vehicle 1000 is internally provided with a battery device 100, which can be arranged at the bottom, head or tail of the vehicle 1000. The battery device 100 can be used for power supply of the vehicle 1000, for example, the battery device 100 can be used as the operating power supply of the vehicle 1000. The vehicle 1000 can also include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the working power demand of the vehicle 1000 during starting, navigation and driving.

[0057] In some embodiments of the present application, the battery device 100 can not only be used as the operating power supply of the vehicle 1000, but also be used as the driving power supply of the vehicle 1000, instead of or partially instead of fuel or natural gas to provide driving power for the vehicle 1000.

[0058] In some embodiments of the present application, the battery device 100 can be a battery monomer, a battery monomer group or a battery pack, referring to Figure 2As shown, the battery device 100 is taken as an example of a battery pack for illustration. The battery device 100 can include a box 10 and battery cells 20, and the battery cells 20 are accommodated in the box 10. The box 10 is used to provide an accommodation space for the battery cells 20, and the box 10 can adopt various structures. In some embodiments, the box 10 can include a first part 11 and a second part 12, and the first part 11 and the second part 12 are mutually covered to jointly define an accommodation space for accommodating the battery cells 20. The second part 12 can be a hollow structure with one end open, and the first part 11 can be a plate-shaped structure, which is covered on the open side of the second part 12 to jointly define the accommodation space with the second part 12. Alternatively, the first part 11 and the second part 12 can both be hollow structures with one side open, and the open side of the first part 11 is covered on the open side of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 can have various shapes, such as a cylinder, a cuboid, etc.

[0059] In the battery device 100, the battery cells 20 can be multiple, and the multiple battery cells 20 can be connected in series, in parallel, or in a mixed manner. The mixed manner means that the multiple battery cells 20 are connected in series and in parallel. The multiple battery cells 20 can be directly connected in series, in parallel, or in a mixed manner, and then the whole of the multiple battery cells 20 is accommodated in the box 10. Of course, the battery device 100 can also be that the multiple battery cells 20 are first connected in series, in parallel, or in a mixed manner to form battery modules, and then the multiple battery modules are connected in series, in parallel, or in a mixed manner to form a whole, which is accommodated in the box 10. The battery device 100 can further include other structures, for example, the battery device 100 can further include a current collecting component for realizing electrical connection between the multiple battery cells 20. The battery cells 20 can have various shapes, such as a cylinder, a flat body, a cuboid, or other shapes.

[0060] Of course, in some other embodiments, the battery device 100 can be integrally arranged with the chassis / body.

[0061] According to some embodiments of the present application, the present application provides a battery device 100, which is described with reference to Figures 3 to 5 As shown, the battery device 100 includes an end cover assembly 21, a shell 22, and an electrode assembly 23. The shell 22 is provided with an opening. The electrode assembly 23 is arranged in the shell 22. The end cover assembly 21 includes a top cover 211, a first plastic part 212, and a pole 213. The top cover 211 is arranged at the opening of the shell 22. The first plastic part 212 is arranged on the side of the top cover 211 away from the electrode assembly 23. The pole 213 is arranged through the top cover 211 and the first plastic part 212. At least part of the surface of the first plastic part 212 is provided with an insulating layer 214, and the heat-resistant temperature of the insulating layer 214 is greater than the heat-resistant temperature of the first plastic part 212.

[0062] refer to Figure 3 As shown, this application uses a battery device 100 with a battery cell 20 as an example for description. The battery cell 20 refers to the smallest unit that makes up the battery. The top cover 211 is a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment. The shape of the top cover 211 can be adapted to the shape of the housing 22 to fit the housing 22. Optionally, the top cover 211 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the top cover 211 is not easily deformed when subjected to compression or impact, allowing the battery cell 20 to have higher structural strength. In some embodiments, the top cover 211 may also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the top cover 211 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc., and this application embodiment does not impose any special limitations on this.

[0063] The first plastic component 212 is disposed on the side of the top cover 211 opposite to the electrode assembly 23, so as to Figure 4 For example, the first plastic part 212 is disposed above the top cover 211 and is fixed to the top cover 211 by a riveting block 215. In some embodiments, refer to... Figure 4 As shown, the first plastic part 212 is a rectangular block structure with a slot on its upper surface, and the riveting block 215 is embedded in the slot of the first plastic part 212. In some embodiments, the material of the first plastic part 212 can be plastic or rubber.

[0064] The electrode post 213 is the core component that physically and electrically connects the electrode assembly 23 to the external circuit. (Refer to...) Figure 4 As shown, the terminal post 213 passes through the top cover 211 and the first plastic part 212, and is used to output or input electrical energy of the battery cell 20. The terminal post 213 is also insulated from the top cover 211 by the first plastic part 212 to prevent the terminal post 213 from directly contacting the top cover 211 and causing an internal short circuit. To allow the terminal post 213 to pass through, both the top cover 211 and the first plastic part 212 have mounting holes, and the mounting holes on the top cover 211 and the first plastic part 212 are aligned. To achieve further insulation and sealing, the end cap assembly 21 also includes a sealing ring 216. The sealing ring 216 is fitted onto the post portion 2132 (described later) and passes through the mounting hole on the top cover 211 together with the post portion 2132. The sealing ring 216 separates the top cover 211 and the terminal post 213 radially and axially. In some embodiments, the electrode post 213 includes a positive electrode post and a negative electrode post. Correspondingly, the first plastic part 212 has two parts, one for the positive electrode post and the other for the negative electrode post. The positive electrode post can be made of aluminum alloy or pure aluminum, and the negative electrode post can be made of copper alloy or pure copper.

[0065] The insulating layer 214 refers to a functional coating formed by a high-temperature resistant insulating material. This application does not specifically limit the formation method of the insulating layer 214; it can be formed by spraying, roller coating, dip coating, doctor blade coating, etc. When the heat resistance temperature of the insulating layer 214 is greater than the melting point of the first plastic part 212, the insulating layer 214 can maintain good insulation performance in a high-temperature environment, thereby helping to improve the insulation stability of the first plastic part 212, reducing the risk of short circuits caused by insulation failure, and thus reducing the thermal runaway problem of the battery device 100 caused by insulation failure.

[0066] The heat resistance temperature of the insulating layer 214 refers to the temperature at which the material maintains its key properties (such as strength, stiffness, insulation, etc.) without significant deterioration. For the insulating layer 214 formed by amorphous polymer, the heat resistance temperature can be expressed by the glass transition temperature (Tg); for the insulating layer 214 formed by crystalline polymer, the heat resistance temperature can be expressed by the melting point (Tm).

[0067] It should be noted that, since the electrode post 213 passes through the first plastic part 212, and the insulating layer 214 is disposed on the surface of the first plastic part 212, therefore, referring to... Figure 5 As shown, the insulating layer 214 has a clearance hole for the electrode post 213 to pass through, and the clearance hole is aligned with the mounting hole on the first plastic part 212.

[0068] refer to Figure 3 As shown, the housing 22 is a component used to cooperate with the top cover 211 to form the internal environment of the battery cell 20, wherein the formed internal environment can accommodate the electrode assembly 23, electrolyte, and other components. The housing 22 and the top cover 211 can be independent components. An opening can be provided on the housing 22, and the top cover 211 closes the opening to form the internal environment of the battery cell 20. The housing 22 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 22 can be determined according to the specific shape and size of the electrode assembly 23.

[0069] Electrode assembly 23 is the component in the battery cell 20 where electrochemical reactions occur. The casing 22 may contain one or more electrode assemblies 23. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator is provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of the electrode assembly, while the portions without active material each constitute a tab. The positive and negative tabs may be located together at one end of the main body or separately at both ends. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs connect to the electrode terminals to form a current loop.

[0070] According to some embodiments of this application, reference is made to Figure 5 As shown, the first plastic part 212 has an insulating layer 214 on both the side facing the top cover 211 and the side away from the top cover 211.

[0071] by Figure 5 For example, the side of the first plastic part 212 facing the top cover 211 refers to the lower surface of the first plastic part 212, and the side of the first plastic part 212 away from the top cover 211 refers to the upper surface of the first plastic part 212. In some embodiments, a slot is formed on the upper surface of the first plastic part 212, and the side of the first plastic part 212 away from the top cover 211 includes the inner surface of the slot. Of course, in some other embodiments, the first plastic part 212 may not have a slot formed on its upper surface, in which case an insulating layer 214 is provided on both the upper and lower surfaces of the first plastic part 212.

[0072] The insulating layer 214 on the side of the first plastic part 212 facing the top cover 211 can reduce the problem of the first plastic part 212 undergoing thermal melting and carbonization at high temperatures. The insulating layer 214 on the side of the first plastic part 212 away from the top cover 211 can further prevent the pole post 213 and the top cover 211 from short-circuiting.

[0073] According to some embodiments of this application, the thickness of the insulating layer 214 is 30μm-300μm.

[0074] The thickness of the insulating layer 214 refers to the thickness on one side. When the insulating layer 214 is provided on both the upper and lower surfaces of the first plastic part 212, the thickness of the insulating layer 214 on the upper and lower surfaces is 30μm-300μm respectively. The thickness of the insulating layer 214 can be any value between 30μm and 300μm. For example, the thickness of the insulating layer 214 can be 30μm, 50μm, 80μm, 100μm, 125μm, 150μm, 175μm, 200μm, 225μm, 250μm, 275μm or 300μm. When the thickness of the insulating layer 214 is between 30μm and 300μm, it helps to improve the heat insulation performance of the insulating layer 214. When heat accumulates in the battery, it can reduce the heat reaching the first plastic part 212, thereby helping to lower the temperature of the first plastic part 212, reducing the risk of heat melting, and further helping to improve the insulation stability of the first plastic part 212.

[0075] In some embodiments, the heat resistance temperature of the insulating layer 214 is 200°C-1200°C.

[0076] Currently, most plastic parts used in battery devices are made of materials such as polypropylene. Polypropylene has a melting point of approximately 160°C. Since the heat resistance temperature of the insulation layer 214 is higher than the melting point of the plastic parts, setting the heat resistance temperature of the insulation layer to 200°C-1200°C allows the structure to remain stable for an extended period without melting during battery device heating and thermal runaway, effectively reducing the risk of insulation failure. The heat resistance temperature of the insulation layer 214 can be any value between 200°C and 1200°C. For example, the heat resistance temperature of the insulation layer 214 can be 200°C, 400°C, 600°C, 800°C, 1000°C, or 1200°C.

[0077] According to some embodiments of this application, reference is made to Figure 4 As shown, the end cap assembly 21 includes a second plastic part 217, which is disposed between the top cover 211 and the electrode assembly 23. At least a portion of the surface of the second plastic part 217 is provided with an insulating layer 214.

[0078] The second plastic component 217 is used to isolate the electrical connection pieces within the housing 22 from the top cover 211 to reduce the risk of short circuits. In some embodiments, with Figure 4 For example, the second plastic part 217 has a shape and size that matches the top cover 211, and it is fitted onto the lower surface of the top cover 211. Exemplarily, the material of the second plastic part 217 can be plastic, rubber, etc. When an insulating layer 214 is provided on at least a portion of the surface of the second plastic part 217, it helps to improve the overall temperature resistance of the second plastic part 217, reduces the problem of insulation failure due to melting of the second plastic part 217, and further reduces the risk of thermal runaway in the battery device 100.

[0079] It should be noted that when the second plastic part 217 is provided on the lower surface of the top cover 211, since the electrode post 213 needs to connect the electrode assembly 23 and the external circuit, the electrode post 213 is also installed on the second plastic part 217. Correspondingly, the second plastic part 217 has a mounting hole, which is aligned with the mounting holes on the top cover 211 and the first plastic part 212.

[0080] According to some embodiments of this application, the second plastic part 217 has an insulating layer 214 on at least one surface facing the electrode assembly 23.

[0081] The second plastic part 217 having an insulating layer 214 on at least the surface facing the electrode assembly 23 means that the second plastic part 217 can have an insulating layer 214 on only the surface facing the electrode assembly 23 (lower surface), or it can have an insulating layer 214 on both the surface facing the electrode assembly 23 and the surface away from the electrode assembly 23 (upper surface). Having an insulating layer 214 on both sides can further provide heat insulation protection for the second plastic part 217.

[0082] The second plastic part 217 is used to insulate and block the electrode assembly 23 and the top cover 211. When an insulating layer 214 is provided on the surface of the second plastic part 217 facing the electrode assembly 23, the risk of the second plastic part 217 melting due to heat can be reduced, thereby reducing the internal short circuit problem caused by direct contact between the electrode assembly 23 and the top cover 211.

[0083] According to some embodiments of this application, reference is made to Figure 4 As shown, the electrode post 213 includes a chassis portion 2131 and a column portion 2132 connected to the chassis portion 2131. The chassis portion 2131 is disposed between the top cover 211 and the electrode assembly 23, and the column portion 2132 passes through the top cover 211 and the first plastic part 212. The chassis portion 2131 has an insulating layer on the side surface facing the top cover 211.

[0084] by Figure 4 For example, the chassis portion 2131 is a rectangular block structure, and a column portion 2132 is erected at the center of its upper surface. The column portion 2132 has a shape that matches the mounting hole, such as the column portion 2132 being a cylinder and the mounting hole being a round hole. When the end cap assembly 21 includes the second plastic part 217, the chassis portion 2131 is in close contact with the lower surface of the second plastic part 217, and the column portion 2132 is sequentially inserted upward through the second plastic part 217, the top cover 211, the first plastic part 212, and the riveting block 215.

[0085] The fact that the chassis part 2131 has an insulating layer on the side facing the top cover 211 means that the upper surface of the chassis part 2131 has an insulating layer. This can prevent short circuits caused by direct contact between the chassis part 2131 and the top cover 211 when the second plastic part 217 fails to melt the insulation.

[0086] According to some embodiments of this application, the insulating layer 214 includes at least one of the following: a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified silicone resin layer, a modified epoxy resin layer, a fluoropolymer layer, and a ceramic material layer.

[0087] The polyimide layer refers to a coating formed solely of polyimide material, and the same applies to other coatings. Insulating layer 214 includes at least one of the following: polyimide layer, polyetheretherketone layer, polyphenylene sulfide layer, polybenzimidazole layer, modified silicone resin layer, modified epoxy resin layer, fluoropolymer layer, and ceramic material layer. This means that insulating layer 214 may include only one of these coatings, or it may be formed by stacking multiple layers of the aforementioned coatings.

[0088] The long-term heat resistance temperature of polyimide (PI) is about 220-300°C, the long-term heat resistance temperature of polyether ether ketone (PEEK) is about 250-270°C, the long-term heat resistance temperature of polyphenylene sulfide (PPS) is about 200-240°C, the long-term heat resistance temperature of polybenzimidazole (PBI) is about 300-370°C, the heat resistance temperature of modified silicone resin and modified epoxy resin is about 200-500°C, the heat resistance temperature of fluoropolymer is above 300°C, and the heat resistance temperature of ceramic material is about 1200°C. Therefore, the above-mentioned materials all have high heat resistance, and the insulating layer 214 formed by the above-mentioned materials has high heat resistance and can maintain stable structure for a long time at high temperature.

[0089] According to some embodiments of the present application, the modified epoxy resin layer comprises one of a phenolic modified epoxy resin layer and a silicone modified epoxy resin layer; and / or, the modified silicone resin layer comprises one of an alkyd modified silicone resin layer, an acrylic modified silicone resin layer, and a polyurethane modified silicone resin layer; and / or, the fluoropolymer layer comprises one of a polytetrafluoroethylene layer, a fluorinated ethylene propylene copolymer layer, a polyvinylidene fluoride layer, and an ethylene-tetrafluoroethylene copolymer layer; and / or, the ceramic material layer comprises one of an aluminum oxide layer, a silicon oxide layer, a magnesium aluminum spinel layer, and a yttrium oxide layer.

[0090] It should be noted that the phenolic modified epoxy resin, the silicone modified epoxy resin, the alkyd modified silicone resin, the acrylic modified silicone resin, and the polyurethane modified silicone resin are all existing materials, which can be obtained by purchase.

[0091] According to some embodiments of the present application, referring to FIG. 2, the insulating layer 214 comprises a first coating layer 2141 and a second coating layer 2142, the first coating layer 2141 comprises one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified silicone resin layer, and a modified epoxy resin layer, and the second coating layer 2142 comprises one of a fluoropolymer layer and a ceramic material layer; the thickness ratio of the first coating layer 2141 to the second coating layer 2142 is (6-9):(1-4). Figure 6 The positional relationship between the first coating layer 2141 and the second coating layer 2142 is not specifically limited in the present application, and the first coating layer 2141 can be arranged to adhere to the first plastic part 212, the second plastic part 217, or the pole 213, or the second coating layer 2142 can be arranged to adhere to the first plastic part 212, the second plastic part 217, or the pole 213.

[0092]

[0093] ​The thickness ratio of the first coating layer 2141 and the second coating layer 2142 can be any value between (6-9):(1-4), and exemplarily, the thickness ratio of the first coating layer 2141 and the second coating layer 2142 can be 6:4, 7:3, 8:2 or 9:1.

[0094] According to some embodiments of the present application, the thickness of the first coating layer 2141 is 18-270 μm; and / or, the thickness of the second coating layer 2142 is 3-120 μm.

[0095] The thickness of the first coating layer 2141 can be any value between 18-270 μm, and exemplarily, the thickness of the first coating layer 2141 can be 18 μm, 27 μm, 30 μm, 45 μm, 60 μm, 90 μm, 135 μm, 180 μm, 225 μm or 270 μm. The thickness of the second coating layer 2142 can be any value between 3-120 μm, and exemplarily, the thickness of the second coating layer 2142 can be 3 μm, 12 μm, 20 μm, 30 μm, 40 μm, 80 μm or 120 μm.

[0096] According to some embodiments of the present application, with reference to Figure 7 As shown in FIG. 14, the insulating layer 214 includes a first coating layer 2141, a second coating layer 2142 and a third coating layer 2143, the first coating layer 2141 includes one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, the second coating layer 2142 includes one of a modified silicone resin layer, a modified epoxy resin layer, and the third coating layer 2143 includes one of a fluoropolymer layer, a ceramic material layer; the thickness ratio of the first coating layer 2141, the second coating layer 2142 and the third coating layer 2143 is (4-6):(3-5):(1-3); or, the first coating layer 2141 includes one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified silicone resin layer, a modified epoxy resin layer, the second coating layer 2142 includes a fluoropolymer layer, and the third coating layer 2143 includes a ceramic material layer, and the thickness ratio of the first coating layer 2141, the second coating layer 2142 and the third coating layer 2143 is (5-9):(0.5-3):(0.5-2).

[0097] The relative position relationship of the first coating 2141, the second coating 2142 and the third coating 2143 is not specifically limited in the present application, and the first coating 2141, the second coating 2142 and the third coating 2143 can be sequentially arranged, or the first coating 2141, the third coating 2143 and the second coating 2142 can be sequentially arranged, or the second coating 2142, the first coating 2141 and the third coating 2143 can be sequentially arranged, or the second coating 2142, the third coating 2143 and the first coating 2141 can be sequentially arranged, or the third coating 2143, the first coating 2141 and the second coating 2142 can be sequentially arranged, or the third coating 2143, the second coating 2142 and the first coating 2141 can be sequentially arranged.

[0098] The thickness ratio of the first coating 2141, the second coating 2142 and the third coating 2143 can be any value between (5-9):(0.5-3):(0.5-2), and exemplarily, the thickness ratio of the first coating 2141, the second coating 2142 and the third coating 2143 can be 5:3:2, 6:2.5:1.5, 7:2:1, 8:1:1 or 9:0.5:0.5.

[0099] According to some embodiments of the present application, the thickness of the first coating 2141 is 12-270 μm; and / or, the thickness of the second coating 2142 is 1.5-150 μm; and / or, the thickness of the third coating 2143 is 1.5-90 μm.

[0100] According to some embodiments of the present application, referring to Figure 8 As shown in the figure, the insulating layer 214 includes the first coating 2141, the second coating 2142, the third coating 2143 and the fourth coating 2144, the first coating 2141 includes one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer and a polybenzimidazole layer, the second coating 2142 includes one of a modified silicone resin layer and a modified epoxy resin layer, the third coating 2143 includes a fluoropolymer layer, and the fourth coating 2144 includes a ceramic material layer; the thickness ratio of the first coating 2141, the second coating 2142, the third coating 2143 and the fourth coating 2144 is (4-5):(3-4):(0.5-2):(0.5-2).

[0101] The relative position relationship of the first coating 2141, the second coating 2142, the third coating 2143 and the fourth coating 2144 is also not specifically limited in the present application.

[0102] The thickness ratio of the first coating 2141, the second coating 2142, the third coating 2143, and the fourth coating 2144 can be any value between (4-5):(3-4):(0.5-2):(0.5-2). For example, the thickness ratio of the first coating 2141, the second coating 2142, the third coating 2143, and the fourth coating 2144 can be 4:3:1.5:1.5, 4:4:1:1, 4:3:2:1, 4:3:1:2, or 5:4:0.5:0.5.

[0103] According to some embodiments of this application, the thickness of the first coating 2141 is 12μm-150μm; and / or, the thickness of the second coating 2142 is 9μm-120μm; and / or, the thickness of the third coating 2143 is 1.5μm-60μm; and / or, the thickness of the fourth coating 2144 is 1.5μm-60μm.

[0104] This application uses a combination of at least two different coatings to further improve high-temperature resistance, thereby further improving the insulation stability of the first plastic part.

[0105] According to some embodiments of this application, reference is made to Figure 4 As shown, a groove 2111 is provided on the side of the top cover 211 facing away from the electrode assembly 23, and the first plastic part 212 is embedded in the groove 2111.

[0106] by Figure 4 For example, a groove 2111 is provided on the upper surface of the top cover 211. The groove 2111 has a shape and size that matches the first plastic part 212. The first plastic part 212 is embedded in the groove 2111 and fixed by the rivet block 215. Embedding the first plastic part 212 in the groove 2111 on the upper surface of the top cover 211 can limit the sealing ring 216 of the column portion 2132 of the pole post 213.

[0107] According to some embodiments of this application, the housing 22 includes one of stainless steel housing, aluminum housing, aluminum alloy housing, copper housing, and iron housing.

[0108] According to some embodiments of this application, this application provides an electrical device including any of the battery devices described above.

[0109] Example

[0110] [End Cap Assembly 21]

[0111] The end cover assembly 21 comprises a top cover 211, a first plastic part 212, a pole 213, an insulation layer 214, a riveting block 215, a sealing ring 216 and a second plastic part 217; the top cover 211 covers the opening of the shell 22, the upper surface of the top cover 211 is provided with a groove 2111, the first plastic part 212 is embedded in the groove 2111 and fixed on the top cover 211 through the riveting block 215; the upper surface of the first plastic part 212 is provided with a slot, and the riveting block 215 is embedded in the slot; the pole 213 comprises a bottom disc part 2131 and a column part 2132, the bottom disc part 2131 is located between the second plastic part 217 and the electrode assembly 23 and arranged on the upper surface of the second plastic part 217, and the column part 2132 is sequentially arranged in the second plastic part 217, the top cover 211, the first plastic part 212 and the riveting block 215 in sequence from top to bottom; the insulation layer 214 is arranged on the upper and lower surfaces of the first plastic part 212, and the insulation layer 214 comprises a first coating layer 2141, a second coating layer 2142 and a third coating layer 2143 arranged in sequence from inside to outside, the first coating layer 2141 is a polyimide layer, the second coating layer 2142 is an acrylic modified silicone resin layer, and the third coating layer 2143 is a polytetrafluoroethylene layer; the thickness of the first coating layer 2141 is 87.5 μm, the thickness of the second coating layer 2142 is 70 μm, and the thickness of the third coating layer is 17.5 μm; the total thickness of the insulation layer 214 is 175 μm; the sealing ring 216 is sleeved on the column part 2132 of the pole 213 and located in the mounting hole on the top cover 211; and the second plastic part 217 is arranged between the top cover 211 and the electrode assembly 23 and arranged on the lower surface of the top cover 211.

[0112] [Shell 22]

[0113] The shell 22 is a square shell structure, and the top of the shell 22 is provided with an opening.

[0114] [Electrode assembly]

[0115] The positive active material lithium iron phosphate, the positive conductive agent conductive carbon black, the positive dispersant polyvinylpyrrolidone (PVP) and the positive binder polyvinylidene fluoride (PVDF) are mixed in a mass ratio of 94:1:2:3, then a solvent N-methyl pyrrolidone (NMP) is added to disperse to form a slurry, and then the slurry is coated on both sides of the positive current collector aluminum foil, and after drying, cold pressing and cutting, a positive electrode sheet is obtained.

[0116] The negative active material artificial graphite, the negative conductive agent conductive carbon black, the thickening agent sodium carboxymethyl cellulose (CMC) and the negative binder styrene butadiene rubber (SBR) are mixed in a mass ratio of 95:1:2:2, then deionized water is added to disperse to form a slurry, and then the slurry is coated on both sides of the negative current collector copper foil, and after drying, cold pressing and cutting, a negative electrode sheet is obtained.

[0117] A double-layer polyethylene / polypropylene film with a thickness of 7 μm is used as a base film of the separator film, and an aluminum oxide ceramic layer is provided on the base film to obtain the separator film.

[0118] [Electrolyte]

[0119] Ethylene carbonate (EC), diethyl carbonate (DEC), and dimethyl carbonate (DMC) are mixed in a volume ratio of 1:1:1 to obtain an organic solvent, and LiPF6 is dissolved in the organic solvent to obtain an electrolyte. The concentration of LiPF6 is 1 mol / L.

[0120] [Cell assembly]

[0121] The positive electrode sheet, the negative electrode sheet, and one end of the two separator films are fixed to the discharge roller in the order of separator film-negative electrode sheet-separator film-positive electrode sheet, and the other end is fixed to the winding shaft after being stacked together. The winding shaft is rotated by a motor to wind the positive electrode sheet, the negative electrode sheet, and the two separator films to obtain an electrode assembly. The electrode assembly 23 is placed in the shell 22, and the end cover assembly 21 is arranged at the opening of the shell 22. Then, the electrolyte is injected, and the cell is obtained after packaging.

[0122] Comparative Example

[0123] Unlike the examples, the comparative example does not provide an insulating layer on the upper and lower surfaces of the first plastic part.

[0124] Performance test

[0125] Overcharge test: first, the cell is pre-treated by 0.5P full charge, then the cell is charged to 1.5 times the voltage (5.475V) or the total charging time reaches 1h in 0.5C constant current mode; if thermal runaway occurs before the cell reaches 5.475V, continue to overcurrent until the 1h condition is met. After 1h, observe whether the cell has swelling, leakage, smoking, fire, explosion, etc.; when the cell has at least one of the following phenomena, it is determined that the cell has thermal runaway: (1) the temperature rise rate of the monitoring point is ≥3℃ / s; (2) fire and explosion.

[0126] Test results

[0127] The test results of the examples and the comparative example are shown in Table 1.

[0128] Table 1: Overcharge test results of examples and comparative examples

[0129]

[0130] The thermal runaway time in Table 1 refers to the time required when the temperature rise rate of the monitoring point is greater than or equal to 3°C / s. It can be seen from Table 1 that the time required when the temperature rise rate of the battery cell monitored in the embodiment of the application is greater than or equal to 3°C / s is advanced, at this time, the heat accumulated in the battery cell is less, and the probability of safety hazards will be reduced. It can also be seen from Table 1 that the battery cell provided with the insulating layer in the embodiment of the application does not appear phenomena such as fire sparks and fire during overcharge testing, and the thermal runaway SOC is advanced, and the positive and negative electrode temperatures of thermal runaway are reduced. This is because the high-temperature-resistant insulating coating improves the thermal stability of the first plastic part, ensures the insulation effect, and avoids the problem of internal short circuit. The battery cell in the comparative example sparks and catches fire during the process test, because the first plastic part melts, causing the top cover to be overlapped with the pole, causing internal short circuit, and then sparking and catching fire.

[0131] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the application, and not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application, and they should be covered in the scope of the claims and the specification of the application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery device, characterized in that, include: The housing has an opening; An electrode assembly disposed within the housing; An end cap assembly, comprising a top cover, a first plastic component, and an electrode post, wherein the top cover is disposed over the opening of the housing, the first plastic component is disposed on the side of the top cover opposite to the electrode assembly, and the electrode post passes through the top cover and the first plastic component. At least a portion of the surface of the first plastic part is provided with an insulating layer, the heat resistance temperature of which is greater than that of the first plastic part.

2. The battery device as claimed in claim 1, characterized in that, The insulating layer is provided on both the side of the first plastic part facing the top cover and the side away from the top cover.

3. The battery device as claimed in claim 1, characterized in that, The thickness of the insulating layer is 30μm-300μm.

4. The battery device according to any one of claims 1 to 3, characterized in that, The end cap assembly includes a second plastic part disposed between the top cap and the electrode assembly, and at least a portion of the surface of the second plastic part is provided with the insulating layer.

5. The battery device as claimed in claim 4, characterized in that, The second plastic part has an insulating layer on at least one surface facing the electrode assembly.

6. The battery device according to any one of claims 1 to 3, characterized in that, The electrode post includes a base portion and a column portion connected to the base portion. The base portion is disposed between the top cover and the electrode assembly, and the column portion passes through the top cover and the first plastic part. The chassis portion has an insulating layer on the surface facing the top cover.

7. The battery device according to any one of claims 1 to 3, characterized in that, The insulating layer includes at least one of the following: a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified silicone resin layer, a modified epoxy resin layer, a fluoropolymer layer, and a ceramic material layer.

8. The battery device as claimed in claim 7, characterized in that, The modified epoxy resin layer includes one of a phenolic modified epoxy resin layer and an organosilicon modified epoxy resin layer. And / or, the modified silicone resin layer includes one of alkyd modified silicone resin layer, acrylic modified silicone resin layer, and polyurethane modified silicone resin layer; And / or, the fluoropolymer layer includes one of the following: a polytetrafluoroethylene layer, a fluorinated ethylene propylene copolymer layer, a polyvinylidene fluoride layer, and an ethylene-tetrafluoroethylene copolymer layer; And / or, the ceramic material layer includes one of the following: an alumina layer, a silicon oxide layer, a magnesium aluminum spinel layer, and a yttrium oxide layer.

9. The battery device as claimed in claim 8, characterized in that, The insulating layer includes a first coating and a second coating. The first coating includes one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified silicone resin layer, and a modified epoxy resin layer. The second coating includes one of a fluoropolymer layer and a ceramic material layer. The thickness ratio of the first coating to the second coating is (6-9):(1-4).

10. The battery device as claimed in claim 9, characterized in that, The thickness of the first coating is 18μm-270μm; and / or the thickness of the second coating is 3μm-120μm.

11. The battery device as claimed in claim 8, characterized in that, The insulating layer comprises a first coating, a second coating, and a third coating. The first coating comprises one of a polyimide layer, a polyetheretherketone layer, a polyphenylene sulfide layer, and a polybenzimidazole layer. The second coating comprises one of a modified silicone resin layer and a modified epoxy resin layer. The third coating comprises one of a fluoropolymer layer and a ceramic material layer. The thickness ratio of the first coating, the second coating, and the third coating is (4-6):(3-5):(1-3). Alternatively, the first coating may include one of a polyimide layer, a polyetheretherketone layer, a polyphenylene sulfide layer, a polybenzimidazole layer, a modified silicone resin layer, or a modified epoxy resin layer; the second coating may include a fluoropolymer layer; and the third coating may include a ceramic material layer. The thickness ratio of the first coating, the second coating, and the third coating may be (5-9):(0.5-3):(0.5-2).

12. The battery device as claimed in claim 11, characterized in that, The thickness of the first coating is 12μm-270μm; and / or, the thickness of the second coating is 1.5μm-150μm; and / or, the thickness of the third coating is 1.5μm-90μm.

13. The battery device as claimed in claim 8, characterized in that, The insulating layer includes a first coating, a second coating, a third coating, and a fourth coating. The first coating includes one of a polyimide layer, a polyether ether ketone layer, a polyphenylene sulfide layer, and a polybenzimidazole layer. The second coating includes one of a modified silicone resin layer and a modified epoxy resin layer. The third coating includes a fluoropolymer layer. The fourth coating includes a ceramic material layer. The thickness ratio of the first coating, the second coating, the third coating, and the fourth coating is (4-5):(3-4):(0.5-2):(0.5-2).

14. The battery device as claimed in claim 13, characterized in that, The thickness of the first coating is 12μm-150μm; and / or, the thickness of the second coating is 9μm-120μm; and / or, the thickness of the third coating is 1.5μm-60μm; and / or, the thickness of the fourth coating is 1.5μm-60μm.

15. The battery device according to any one of claims 1 to 3, characterized in that, A groove is formed on the surface of the top cover opposite to the electrode assembly, and the first plastic part is embedded in the groove.

16. The battery device according to any one of claims 1 to 3, characterized in that, The casing includes one of the following: stainless steel casing, aluminum casing, aluminum alloy casing, copper casing, and iron casing.

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

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