Battery device, electric equipment and energy storage device

Abstract

The utility model is suitable for the technical field of batteries, and provides a battery device, electric equipment and an energy storage device. The battery device comprises a plurality of battery monomers and at least one heat insulation pad, the heat insulation pad is arranged between the adjacent battery monomers, the heat insulation pad comprises a core material layer and a packaging layer wrapping the surface of the core material layer, the core material layer comprises a heat insulation part and a phase change part, the heat insulation part is made of a heat insulation material, the phase change part is made of a phase change material, and the packaging layer at least can seal the phase change part. According to the technical scheme provided by the embodiment of the invention, the technical problem of heat spreading in the battery device can be relieved.

Description

Technical Field

[0001] The present application relates to the field of batteries, and in particular to a battery device, electrical equipment and energy storage device. Background Art

[0002] A battery device generally includes multiple battery cells, which are connected and arranged in a certain order. When one of the battery cells experiences thermal runaway, the heat continues to accumulate and transfer to the adjacent battery cells, which can easily cause chain thermal runaway to spread and damage the battery device. Utility Model Content

[0003] In view of this, embodiments of the present application provide a battery device, an electrical device, and an energy storage device, which are used to alleviate the technical problem of heat propagation in the battery device.

[0004] An embodiment of the first aspect of the present application provides a battery device, comprising: a plurality of battery cells; at least one thermal insulation pad, the thermal insulation pad being arranged between adjacent battery cells, the thermal insulation pad comprising a core material layer and a packaging layer coated on the surface of the core material layer, the core material layer comprising a thermal insulation portion and a phase change portion, the thermal insulation portion adopts a thermal insulation material, the phase change portion adopts a phase change material, and the packaging layer can at least seal the phase change portion.

[0005] In the battery device provided by the above embodiment, an insulating part is provided in the insulating pad, and the insulating material in the insulating part can effectively prevent heat conduction between battery cells, prevent the thermal runaway of some battery cells from being transmitted to adjacent battery cells, thereby inhibiting the spread of heat in the battery device. At the same time, a phase change part is provided in the insulating pad, and the phase change material in the phase change part undergoes a phase change reaction and quickly absorbs a large amount of heat, which can prevent local overheating from causing structural damage to the insulating pad, thereby improving the reliability of the insulating pad. Therefore, the above battery device can effectively alleviate the problem of heat spread in the battery device and improve the safety of the battery device by providing a thermal insulation pad and improving the structure of the thermal insulation pad.

[0006] In some embodiments, a plurality of battery cells are arranged along a first direction, the battery cells include two opposite ends in a second direction perpendicular to the first direction, and a pressure relief mechanism is provided at one end, and along the second direction, the core material layer includes a first portion close to the pressure relief mechanism and a second portion away from the pressure relief mechanism, and the mass of the phase change material contained in the first portion is greater than the mass of the phase change material contained in the second portion.

[0007] The above design improves the structural rationality of the thermal insulation pad, and the phase change material can quickly absorb heat in the high temperature area and achieve the purpose of cooling.

[0008] In some embodiments, the insulation part includes an insulation core board, on which a flow channel is provided, the flow channel penetrates the insulation core board along the thickness direction of the insulation core board, a phase change material is provided in the flow channel, and the encapsulation layer is attached to the outer surface of the insulation core board and covers the flow channel.

[0009] The above design can simplify the structure of the core material layer and reduce the difficulty of processing and manufacturing the thermal insulation pad. At the same time, since the structural design of the flow channel is more flexible, the flow channel can be designed into different shapes and sizes to meet different thermal management requirements of the battery device.

[0010] In some embodiments, the flow channel is a continuous structure.

[0011] The above design can enhance the heat transfer between the phase change materials in the flow channel, making the heat distribution of the phase change materials at different positions more uniform, thereby further improving the heat absorption capacity and heat absorption efficiency of the thermal insulation pad.

[0012] In some embodiments, a plurality of battery cells are arranged along a first direction, the battery cells include two opposite ends in a second direction perpendicular to the first direction, and a pressure relief mechanism is provided at one end, and along the second direction, the core material layer includes a first portion close to the pressure relief mechanism and a second portion away from the pressure relief mechanism, and the total volume of the flow channel of the first portion is greater than the total volume of the flow channel of the second portion.

[0013] With the above design, the heat insulation pad has a reasonable structure and higher reliability.

[0014] In some embodiments, the outer edges of the insulating core are provided with a phase change material.

[0015] With the above design, a thermal barrier can be formed at the outer edge of the thermal insulation core board, thereby preventing the edge of the thermal insulation pad from structural damage due to local overheating.

[0016] In some embodiments, the battery device includes a plurality of battery groups distributed along a third direction, each battery group includes a plurality of battery cells arranged along a first direction, thermal insulation pads are arranged between the battery cells of adjacent battery groups, thermal insulation pads are arranged between adjacent battery cells in each battery group, and the first direction is perpendicular to the third direction.

[0017] The above design can further alleviate the problem of heat spread in the battery device and improve the safety of the battery device.

[0018] In some embodiments, along the arrangement direction of the plurality of battery cells, the projected area of ​​the heat insulation portion on the battery cell is S1, the projected area of ​​the phase change portion on the battery cell is S2, and 3.5≤S1 / S2≤8.

[0019] By adopting the above design, by reasonably limiting the ratio range of S1 and S2, the thermal insulation performance and heat absorption capacity of the thermal insulation pad can be balanced, so that the thermal insulation pad has a good thermal insulation effect and can also achieve efficient temperature regulation.

[0020] In some embodiments, 1500 mm 2 ≤S1≤8000mm 2 , and / or 400mm 2 ≤S2≤1000mm 2 .

[0021] By adopting the above design, the range of the heat insulating part and the phase change part in the heat insulating pad is further limited, making the design of the heat insulating pad more reasonable.

[0022] In some embodiments, the thermal conductivity of the thermal insulation material is K1, the thermal conductivity of the phase change material is K2, and K2 / K1≥12.

[0023] By adopting the above design and reasonably limiting the ratio of K2 / K1, the reliability of the thermal insulation pad is improved.

[0024] In some embodiments, K1 ≤ 0.04 W / m·k, and / or K2 ≥ 0.52 W / m·k.

[0025] With the above design, the thermal insulation pad combines a low thermal conductivity insulation material with a higher thermal conductivity phase change material, which can not only prevent heat transfer between adjacent battery cells, but also quickly achieve temperature regulation, making the thermal insulation pad more reliable.

[0026] In some embodiments, the specific heat capacity of the thermal insulation material is C1, and / or the specific heat capacity of the phase change material is C2, C2 / C1≥3.

[0027] By adopting the above design and reasonably limiting the ratio of C2 / C1, the reliability of the thermal insulation pad is improved.

[0028] In some embodiments, 0.2 kJ / (kg·k)≤C1≤1.4 kJ / (kg·k), and / or C2≥4 kJ / (kg·k).

[0029] By adopting the above design, by setting a low specific heat capacity insulation material and a high specific heat capacity phase change material, heat conduction can be effectively prevented and rapid temperature regulation can be achieved.

[0030] In some embodiments, the thermal decomposition temperature of the thermal insulation material is Tm≥1100°C.

[0031] The above design can further reduce the risk of structural damage to the thermal insulation pad due to high temperature, thereby improving the reliability of the thermal insulation pad.

[0032] An embodiment of the second aspect of the present application provides an electrical device, comprising the battery device in the first aspect, wherein the battery device is used to store or provide electrical energy.

[0033] The electrical equipment provided in the above embodiment improves the reliability and safety of the electrical equipment by adopting the battery device in the first aspect.

[0034] An embodiment of the third aspect of the present application provides an energy storage device, including the battery device in the first aspect, and the battery device is used to store or provide electrical energy.

[0035] The energy storage device provided in the above embodiment, by adopting the battery device in the first aspect, improves the reliability and safety of the energy storage device.

[0036] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or conventional technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0038] Figure 1 is a schematic structural diagram of a vehicle provided in an embodiment of the present application;

[0039] Figure 2 is an exploded view of a battery device provided in an embodiment of the present application;

[0040] Figure 3 is a schematic diagram of the structure of a battery cell provided in an embodiment of the present application;

[0041] Figure 4 yes Figure 3 An exploded view of the battery cell shown;

[0042] Figure 5 It is an arrangement diagram of battery cells and thermal insulation pads provided in an embodiment of the present application;

[0043] Figure 6 It is a schematic diagram of the interlayer structure of the thermal insulation pad provided in the embodiment of the present application;

[0044] Figure 7 is a schematic structural diagram of a core material layer provided in one embodiment of the present application;

[0045] Figure 8 It is a schematic structural diagram of a core material layer provided in another embodiment of the present application.

[0046] The meanings of the marks in the figure are:

[0047] 1000, vehicle; 100, battery device; 200, controller; 300, motor;

[0048] 10. Box body; 11. First box body; 12. Second box body;

[0049] 20. Battery cell; 21. End cover; 21a. Electrode terminal; 22. Shell; 22a. Large side wall; 23. Electrode assembly; 23a. Tab; 24. Pressure relief mechanism;

[0050] 30. Thermal insulation pad; 31. Core material layer; 32. Packaging layer; 33. Thermal insulation material; 34. Phase change material; 35. Adhesive layer. DETAILED DESCRIPTION

[0051] The following embodiments of the technical solution of the present application will be described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0053] 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 clearly and specifically defined.

[0054] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0055] 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, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0056] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0057] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0058] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0059] A battery device generally includes a plurality of battery cells, which are connected and arranged in a certain order. When one of the battery cells experiences thermal runaway, its heat will be transferred from one battery cell to an adjacent battery cell, thereby causing heat spread in the entire battery device.

[0060] At present, thermal management components can be set in battery devices to prevent heat transfer and thus inhibit the spread of heat in the battery device. However, existing thermal management components are of a single type and simple structure, resulting in limited thermal insulation capabilities and relatively low reliability. In some cases, especially for battery cells with high energy density, a large amount of heat accumulates in a short period of time after thermal runaway occurs in the battery cells. Local high temperature can cause damage to the thermal management components, thereby affecting the thermal insulation performance of the thermal management components or causing the thermal management components to fail.

[0061] Based on the above problems, an embodiment of the present application provides a battery device, including multiple battery cells and a thermal insulation pad arranged between adjacent battery cells, the thermal insulation pad including a core material layer and a packaging layer, the core material layer including a thermal insulation portion provided with a thermal insulation material and a phase change portion provided with a phase change material. In this way, heat conduction between adjacent battery cells can be prevented by the thermal insulation portion, and temperature regulation can be achieved by absorbing a large amount of heat by the phase change portion, so that the thermal insulation pad has good thermal insulation performance and is not easy to be damaged, can effectively alleviate the problem of heat spread in the battery device, and improve the safety of the battery device.

[0062] The battery device provided in the embodiment of the present application can be used in various energy storage systems that use the battery device as a power source or use the battery device as an energy storage element. The electrical equipment can be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, a battery car, an electric car, a ship, a spacecraft, and the like. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the like, and the spacecraft can include an airplane, a rocket, a space shuttle, and a spacecraft, and the like.

[0063] For the convenience of explanation, the embodiment of the present application is described by taking an electrical device as a vehicle 1000 as an example.

[0064] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 100 is provided inside the vehicle 1000, and the battery device 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery device 100 may be used to power the vehicle 1000, for example, the battery device 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0065] In some embodiments of the present application, the battery device 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0066] Please refer to Figure 2 , Figure 2An exploded view of a battery device 100 provided in some embodiments of the present application. The battery device 100 includes a case 10 and a battery cell 20, and the battery cell 20 is contained in the case 10. Among them, the case 10 is used to provide a storage space for the battery cell 20, and the case 10 can adopt a variety of structures. In some embodiments, the case 10 may include a first case 11 and a second case 12, and the first case 11 and the second case 12 cover each other, and the first case 11 and the second case 12 jointly define a storage space for accommodating the battery cell 20. The second case 12 may be a hollow structure with one end open, and the first case 11 may be a plate-like structure, and the first case 11 covers the open side of the second case 12, so that the first case 11 and the second case 12 jointly define a storage space; the first case 11 and the second case 12 may also be hollow structures with one side open, and the open side of the first case 11 covers the open side of the second case 12. Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder, a cuboid, etc.

[0067] In some embodiments, the box 10 can be used as a part of the chassis structure of the vehicle 1000. For example, part of the box 10 can become at least a part of the floor of the vehicle 1000, or part of the box 10 can become at least a part of the cross beam and longitudinal beam of the vehicle 1000.

[0068] In some embodiments, the battery device 100 may not include the box body 10 , but rather a plurality of battery cells 20 may be connected and integrated into a whole by a necessary fixing structure and then assembled into the vehicle 1000 .

[0069] In the battery device 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; or, the multiple battery cells 20 may be first connected in series, in parallel, or in a mixed connection to form a battery cell assembly, and the multiple battery cell assemblies are then connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery device 100 may also include other structures, for example, the battery device 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0070] The battery cell 20 refers to the smallest unit constituting the battery device 100. Each battery cell 20 may be a secondary battery. A secondary battery refers to a battery cell 20 that can be continuously used by activating the active material by charging after the battery cell 20 is discharged. The battery cell 20 may be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0071] Please refer to Figure 3 and Figure 4 , Figure 3 This is a schematic diagram of the structure of a battery cell 20 provided in some embodiments of the present application. Figure 4 for Figure 3 An exploded view of a battery cell 20 is shown. The battery cell 20 includes an end cap 21, a housing 22, an electrode assembly 23 and other functional components.

[0072] The end cap 21 refers to a component that covers the opening of the shell 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 can be adapted to the shape of the shell 22 to match the shell 22. Optionally, the end cap 21 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 21 is not easily deformed when squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals 21a can be provided on the end cap 21. The electrode terminal 21a can be used to electrically connect with the electrode assembly 23 for outputting or inputting electrical energy of the battery cell 20. In some embodiments, the end cap 21 can also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the end cap 21 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose special restrictions on this. In some embodiments, an insulating member may be provided inside the end cap 21, and the insulating member may be used to isolate the electrical connection components in the housing 22 from the end cap 21 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, or the like.

[0073] The shell 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 23, the electrolyte and other components. The shell 22 and the end cap 21 can be independent components, and an opening can be set on the shell 22, and the internal environment of the battery cell 20 is formed by covering the opening with the end cap 21 at the opening. Without limitation, the end cap 21 and the shell 22 can also be integrated. Specifically, the end cap 21 and the shell 22 can form a common connection surface before other components are put into the shell, and when it is necessary to encapsulate the interior of the shell 22, the end cap 21 covers the shell 22. The shell 22 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 22 can be determined according to the specific shape and size of the electrode assembly 23. The material of the shell 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0074] The electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 23 may be included in the housing 22. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 23, and the parts of the positive and negative electrode sheets without active materials each constitute a tab 23a. The positive tab and the negative tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the tab 23a connects the electrode terminals to form a current loop.

[0075] The technical solution provided in the embodiments of the present application is described below with reference to the accompanying drawings.

[0076] According to some embodiments of the present application, referring to Figures 5 to 7 , Figure 5 This is a diagram showing the arrangement of the battery cells 20 and the thermal insulation pad 30 in the battery device 100 provided in an embodiment of the present application. Figure 6 This is a schematic diagram of the interlayer structure of the thermal insulation pad 30 provided in the embodiment of the present application. Figure 7 A schematic diagram of the structure of the core material layer 31 in the thermal insulation pad 30 provided in an embodiment of the present application. An embodiment of the first aspect of the present application provides a battery device 100. The battery device 100 includes a plurality of battery cells 20 and at least one thermal insulation pad 30. The thermal insulation pad 30 is arranged between adjacent battery cells 20, and the thermal insulation pad 30 includes a core material layer 31 and a packaging layer 32 coated on the surface of the core material layer 31, and the core material layer 31 includes a thermal insulation portion and a phase change portion, the thermal insulation portion adopts a thermal insulation material 33, and the phase change portion adopts a phase change material 34, and the packaging layer 32 can at least seal the phase change portion.

[0077] like Figure 5As shown, the width direction of the battery cell 20 is defined as the first direction Y. Figure 7 As shown, the height direction of the battery cell 20 is defined as the second direction Z.

[0078] The plurality of battery cells 20 are arranged in a certain order, for example, the plurality of battery cells 20 may be arranged linearly along a single direction, or may be divided into a plurality of groups and arranged flatly, but the invention is not limited thereto.

[0079] The thermal insulation pad 30 is a multilayer composite material having a certain thickness and including two opposite sides in the thickness direction. The two sides of the thermal insulation pad 30 face different battery cells 20 respectively. The shape and size of the thermal insulation pad 30 can be designed according to the size of the battery cell 20 and the layout of the battery cell 20. The core material layer 31 is the core functional layer of the thermal insulation pad 30. The core material layer 31 is divided into a thermal insulation part and a phase change part. The thermal insulation part and the phase change part correspond to different parts of the battery cell 20 respectively. The thermal insulation part includes a thermal insulation material 33 and is used to prevent heat conduction between the battery cells 20. The thermal insulation material 33 has a low thermal conductivity. For example, the thermal insulation material 33 can be ceramic fiber, glass fiber or aerogel, but is not limited thereto. The phase change part includes a phase change material 34 and is used to absorb the heat released by the battery cell 20. The phase change material 34 has a high specific heat capacity. For example, the phase change material 34 can be paraffin, fatty acid or a salt mixture, but is not limited thereto. It can be understood that the phase change material 34 will undergo a phase change when absorbing heat, for example, from a solid state to a liquid state, thereby absorbing a large amount of latent heat, which plays a role in cooling or delaying the rise of the ambient temperature. The arrangement of the thermal insulation part and the phase change part depends on the design requirements. The encapsulation layer 32 is an external protective film layer of the thermal insulation pad 30, which can seal the phase change material 34 of the phase change part to prevent the phase change material 34 from leaking during the phase change process. The encapsulation layer 32 can be attached to the entire outer surface of the core material layer 31, or it can also be attached to a local position of the core material layer 31, and can be specifically designed according to the structure of the core material layer 31. The encapsulation layer 32 is generally made of a material that is resistant to high temperature, corrosion-resistant and has good mechanical strength. For example, the encapsulation layer 32 can be a polyimide film or a polytetrafluoroethylene film, but is not limited to this.

[0080] In the battery device 100 provided in the above embodiment, a heat insulating pad 30 is arranged between adjacent battery cells 20. The heat insulating pad 30 includes a core material layer 31. The core material layer 31 includes a heat insulating portion and a phase change portion. When some battery cells 20 in the battery device 100 experience thermal runaway, the heat insulating portion can effectively prevent heat conduction between the battery cells 20, preventing more battery cells 20 from failing due to heat. At the same time, the phase change portion undergoes a phase change reaction and quickly absorbs a large amount of heat, which can reduce the temperature or delay the rise of the ambient temperature, thereby avoiding the problem of structural damage to the heat insulating pad 30 caused by local overheating, and improving the reliability of the heat insulating pad 30. In addition, the heat insulating pad 30 also includes a packaging layer 32 coated on the surface of the core material layer 31. The packaging layer 32 is used to seal the phase change portion, which can prevent the phase change material 34 of the phase change portion from leaking. In summary, the battery device 100 can effectively alleviate the problem of heat spread in the battery device 100 and improve the safety of the battery device 100 by disposing the thermal insulation pads 30 between the battery cells 20 and improving the structure of the thermal insulation pads 30 .

[0081] Please refer to Figure 3 , Figure 5 and Figure 7 In some embodiments, a plurality of battery cells 20 are arranged along a first direction Y, and the battery cells 20 include two opposite ends in a second direction Z perpendicular to the first direction Y, and a pressure relief mechanism 24 is provided at one end thereof. Along the second direction Z, the core material layer 31 includes a first portion close to the pressure relief mechanism 24 and a second portion away from the pressure relief mechanism 24, and the mass of the phase change material 34 contained in the first portion is greater than the mass of the phase change material 34 contained in the second portion.

[0082] The pressure relief mechanism 24 refers to an element or component that is actuated to quickly release the internal pressure or temperature of the battery cell 20 when the internal pressure or temperature reaches a predetermined threshold. "Actuation" means that the pressure relief mechanism 24 is in action or activated to a certain state, wherein the action produced by the pressure relief mechanism 24 may include but is not limited to at least a portion of the pressure relief mechanism 24 being broken, shattered, torn or opened. The pressure relief mechanism 24 may take the form of an explosion-proof valve, an air valve, a pressure relief valve or a safety valve, and may specifically adopt a pressure-sensitive or temperature-sensitive element or structure. When the internal pressure or temperature of the battery cell 20 reaches a predetermined threshold, the pressure relief mechanism 24 performs an action or a weak structure provided in the pressure relief mechanism 24 is destroyed, thereby forming an opening or channel for the internal pressure or temperature to be released.

[0083] The pressure relief mechanism 24 can be opened when the battery cell 20 has thermal runaway, releasing the runaway energy and runaway eruptions generated by the thermal runaway. Therefore, a large amount of heat is easily accumulated at the end close to the pressure relief mechanism 24 and local high temperature occurs, and the corresponding temperature regulation requirement is also higher. The heat absorption of the phase change material 34 can be calculated by the formula Q=m*L, where Q represents the absorbed heat, m represents the mass of the phase change material 34, and L represents the latent heat value of the phase change material 34. According to the above formula, the heat absorption capacity of the insulation pad 30 is proportional to the mass of the phase change material 34. In the above embodiment, more phase change materials 34 are arranged on the side close to the pressure relief mechanism 24, which can improve the heat absorption capacity and heat absorption efficiency of the insulation pad 30, thereby further improving the reliability of the insulation pad 30.

[0084] like Figure 5 As shown, the length direction of the battery cell 20 is defined as the third direction X. It can be understood that the distribution of the first part and the second part is related to the setting position of the pressure relief mechanism 24. When the battery cell 20 is a rectangular parallelepiped, the thermal insulation pad 30 faces the large side wall 22a of the battery cell 20, and the pressure relief mechanism 24 can be set on a wall of the shell 22 along the third direction X. At this time, the first part and the second part are distributed along the third direction X.

[0085] In some embodiments, the insulation part includes an insulation core board, on which a flow channel is provided, the flow channel penetrates the insulation core board along the thickness direction of the insulation core board, a phase change material 34 is provided in the flow channel, and the encapsulation layer 32 is attached to the outer surface of the insulation core board and covers the flow channel.

[0086] The heat-insulating core plate has a low thermal conductivity, and may be formed of, for example, ceramic fiber, glass fiber, or aerogel. The heat-insulating core plate has a certain hardness and strength to maintain its own structural stability and support the flow channel structure. The shape and size of the heat-insulating core plate may be designed according to the heat-insulating requirements, the size of the battery cell 20, and the layout of the battery cell 20.

[0087] Please refer to Figure 7 and Figure 8 , Figure 7 and Figure 8 Two different flow channel designs. The flow channel can be in a variety of shapes, for example, the flow channel can be straight, curved or other irregular shapes. The size of the flow channel and the arrangement on the insulation core plate can be designed according to the heat absorption requirements. It can be understood that since the phase change material 34 is filled in the flow channel, the size of the flow channel will limit the filling amount of the phase change material 34, and ultimately affect the heat absorption capacity and heat absorption efficiency of the insulation pad 30.

[0088] The structure of the encapsulation layer 32 is not unique. For example, in some embodiments, the encapsulation layer 32 can cover the entire surface of the insulation core plate to achieve sealing of the flow channel, or the encapsulation layer 32 can also be targeted to cover the local surface where the flow channel is set. It is understood that in some implementations, in addition to the sealing function, the encapsulation layer 32 can also achieve mechanical isolation and electrical insulation.

[0089] In the above embodiment, on the one hand, the core material layer 31 has a simple structure and is easy to process and manufacture. On the other hand, the structural design of the flow channel is more flexible and the flow channel can be designed to have different shapes and sizes to meet different thermal management requirements of the battery device 100.

[0090] It can be understood that in some other embodiments, the thermal insulation material 33 and the phase change material 34 can be independently provided and assembled together to form a block-shaped layout structure.

[0091] In some embodiments, a coating may be provided on the inner wall of the flow channel to isolate the thermal insulation material 33 and the phase change material 34. If the thermal insulation core plate is in direct contact with the phase change material 34, good compatibility and stability between the two must be ensured.

[0092] In some embodiments, a plurality of battery cells 20 are arranged along a first direction Y, the battery cells 20 include two opposite ends in a second direction Z perpendicular to the first direction Y, and a pressure relief mechanism 24 is provided at one end, and along the second direction Z, the core material layer 31 includes a first portion close to the pressure relief mechanism 24 and a second portion away from the pressure relief mechanism 24, and the total volume of the flow channel of the first portion is greater than the total volume of the flow channel of the second portion.

[0093] The volume of the flow channel is proportional to the filling amount and total heat absorption capacity of the phase change material 34. The increase in the total volume of the flow channel can also be understood as an increase in the proportion and density of the flow channel on the thermal insulation core board.

[0094] In the above embodiment, according to the heat distribution when the battery cell 20 has thermal runaway, the flow channel volume is targetedly increased in a local area of ​​the insulation pad 30 to improve the quality of the filled phase change material 34, which can further improve the heat absorption capacity and heat absorption efficiency of the insulation pad 30, thereby further improving the reliability of the insulation pad 30.

[0095] In some embodiments, the flow channel is a continuous structure.

[0096] For example, the flow channel can be a closed flow channel. A closed flow channel means that all the flow channels in the core material layer 31 form a ring-shaped or ring-like closed loop, and there are no breakpoints on the path of the flow channel. For example, the outer contour of the flow channel can be a circle, an ellipse, a square or other closed geometric shape.

[0097] The above design can enhance the heat transfer between the phase change materials 34 in the flow channel, making the heat distribution of the phase change materials 34 at different positions more uniform, thereby facilitating further improving the heat absorption capacity and heat absorption efficiency of the thermal insulation pad 30 .

[0098] In some embodiments, the flow channel is a non-closed structure. That is, the flow channel in the core material layer 31 is not a structure that is connected as a whole to form a loop. It can be a connected but non-closed structure, such as a structure that is wound from the inside to the outside, a serpentine structure, etc.; it can also be that part of the flow channel is a closed structure, and part of the flow channel is an independent strip structure, a block structure, a radial structure or some irregular structures.

[0099] It can be understood that in some embodiments, the heat insulation part and the phase change part can also be designed as a strip structure, and the heat insulation part and the phase change part are alternately arranged along a single direction.

[0100] Please refer to Figure 7 In some embodiments, the outer edge of the insulation core is provided with a phase change material 34 .

[0101] For example, the heat insulation core board can be a square board, and the outer edge of the heat insulation core board refers to the four sides of the heat insulation core board. The phase change material 34 at the outer edge surrounds the heat insulation core board.

[0102] It can be understood that the heat insulation portion includes all regions where the heat insulation material 33 is disposed, and the phase change portion includes all regions where the phase change material 34 is disposed.

[0103] In the above embodiment, the phase change material 34 is used to form a thermal barrier at the outer edge of the thermal insulation core plate, which can slow down the temperature rise at the edge of the thermal insulation pad 30, thereby reducing the risk of structural damage at the edge of the thermal insulation pad 30.

[0104] In some embodiments, the battery device 100 includes a plurality of battery groups distributed along a third direction X, each battery group includes a plurality of battery cells 20 arranged along a first direction Y, thermal insulation pads 30 are arranged between the battery cells 20 of adjacent battery groups, thermal insulation pads 30 are arranged between adjacent battery cells 20 in each battery group, and the first direction Y and the third direction X are perpendicular to each other.

[0105] The heat insulation pad 30 needs to be arranged away from the pressure relief mechanism 24. As an example, the battery cell 20 includes two opposite ends in the second direction Z, and one end is provided with the pressure relief mechanism 24. The first direction Y, the second direction Z, and the third direction X are perpendicular to each other.

[0106] As an example, the second direction Z and the third direction X may constitute a large side wall 22 a of the housing 22 , and the second direction Z and the first direction Y may constitute a wall surface connecting the large side wall 22 a .

[0107] By adopting the above design, the isolation effect between the battery cells 20 in the battery device 100 can be further improved, thereby further alleviating the problem of heat spread in the battery device 100 and improving the safety of the battery device 100 .

[0108] In some embodiments, along the arrangement direction of the plurality of battery cells 20 , the projected area of ​​the heat insulation portion on the battery cell 20 is S1 , the projected area of ​​the phase change portion on the battery cell 20 is S2 , and 3.5≤S1 / S2≤8.

[0109] The thermal insulation pad 30 can be disposed in close contact with the battery cell 20 , and S1 and S2 are heat exchange areas between the thermal insulation portion and the phase change portion and the battery cell 20 .

[0110] S1 / S2 reflects the ratio of the heat insulation part to the phase change part in the core material layer 31, and the ratio of the two will affect the heat insulation performance and heat absorption capacity of the heat insulation pad 30. If S1 / S2 is too small, it means that the heat insulation part accounts for a small proportion, and the heat insulation performance of the heat insulation pad 30 is relatively poor, and it may not be able to meet the heat insulation requirements of some high energy density battery cells 20; if S1 / S2 is too large, it means that the phase change part accounts for a small proportion, and the heat absorption capacity of the heat insulation pad 30 is relatively poor, and it may not be able to meet the temperature regulation requirements of some high energy density battery devices 100.

[0111] In the above embodiment, by reasonably limiting the ratio range of S1 and S2, the thermal insulation performance and heat absorption capacity of the thermal insulation pad 30 can be balanced, so that the thermal insulation pad 30 can provide good thermal insulation effect and achieve efficient temperature regulation.

[0112] The following is a set of experimental data to verify the effect of the technical solution provided by the above embodiment. Please refer to Table 1, which is an experimental comparison table of the correlation between the value of S1 / S2 and heat spread. In this test, the battery cells 20 in each group of samples are kept the same, the position of the thermal insulation pad 30 relative to the corresponding side wall of the battery cell 20 is consistent, the thickness, structure and other characteristics of the thermal insulation pad 30 are consistent, and the test environment is consistent.

[0113]

[0114] In some embodiments, 1500 mm 2 ≤S1≤8000mm 2 , and / or 400mm 2 ≤S2≤1000mm 2 .

[0115] Optionally, in some embodiments provided in the present application, 3.5≤S1 / S2≤8, 1500mm 2 ≤S1≤8000mm 2 , 400mm 2 ≤S2≤1000mm2 .

[0116] In the above embodiment, the range of the insulation part and the phase change part in the insulation pad 30 is further limited, so that the design of the insulation pad 30 is more reasonable, which is beneficial to further improve the thermal management effect and reliability of the insulation pad 30.

[0117] It can be understood that the size of the thermal insulation pad 30 is related to the size of the battery cell 20 . Accordingly, the size of the thermal insulation pad 30 , as well as the specific sizes of the thermal insulation portion and the phase change portion can be adjusted according to the structure of the battery device 100 .

[0118] In some embodiments, the thermal conductivity of the thermal insulation material 33 is K1, the thermal conductivity of the phase change material 34 is K2, and K2 / K1≥12.

[0119] Thermal conductivity is a physical quantity that indicates the thermal conductivity of a material. The larger the thermal conductivity, the better the thermal conductivity. If the thermal conductivity K1 of the thermal insulation material 33 is similar to the thermal conductivity K2 of the phase change material 34, it may be that the thermal conductivity of the thermal insulation material 33 is too high, which will cause the thermal insulation pad 30 to be unable to effectively prevent heat transfer between the battery cells 20, or it may be that the thermal conductivity of the phase change material 34 is too low, which will cause the thermal insulation pad 30 to be unable to quickly absorb the large amount of heat released by the battery cell 20 when it is in thermal runaway.

[0120] In the above embodiment, the reliability of the thermal insulation pad 30 can be improved by reasonably limiting the ratio of K2 / K1.

[0121] In some embodiments, the thermal conductivity K1 of the thermal insulation material 33 is ≤0.04 W / m·k.

[0122] In the above embodiment, the heat insulating material 33 has a low thermal conductivity, and the heat insulating material 33 can effectively prevent heat transfer between adjacent battery cells 20 , so that the heat insulating pad 30 has good heat insulating performance.

[0123] In some embodiments, the thermal conductivity K2 of the phase change material 34 is ≥ 0.52 W / m·k.

[0124] In the above embodiment, the phase change material 34 has a high thermal conductivity, and the phase change material 34 can quickly absorb heat to achieve temperature regulation. At the same time, the high thermal conductivity also enables the local phase change material 34 to quickly conduct heat to other positions in the phase change part after absorbing heat, which is beneficial to improving the uniformity of heat distribution in the phase change part, so that the thermal insulation pad 30 has good heat absorption capacity.

[0125] In some embodiments, the thermal conductivity K1 of the thermal insulation material 33 is ≤0.04 W / m·k, and the thermal conductivity K2 of the phase change material 34 is ≥0.52 W / m·k.

[0126] In the above embodiment, the thermal insulation pad 30 combines the thermal insulation material 33 with low thermal conductivity and the phase change material 34 with higher thermal conductivity, which can not only prevent heat transfer between adjacent battery cells 20, but also quickly achieve temperature regulation, thereby achieving efficient and reliable thermal management.

[0127] In some embodiments, the specific heat capacity of the thermal insulation material 33 is C1, the specific heat capacity of the phase change material 34 is C2, and C2 / C1≥3.

[0128] The specific heat capacity reflects the ability of a material to absorb or release heat when the temperature changes. The higher the specific heat capacity, the stronger the heat absorption capacity. If the ratio of C2 / C1 is too small, it means that the heat absorption capacity of the phase change material 34 is relatively poor, and may not meet the needs of rapid cooling of some high energy density battery devices 100.

[0129] In the above embodiment, the reliability of the thermal insulation pad 30 can be improved by reasonably limiting the ratio of C2 / C1.

[0130] In some embodiments, 0.2 kJ / (kg·k)≤C1≤1.4 kJ / (kg·k), and / or C2≥4 kJ / (kg·k).

[0131] In the above embodiment, by providing a thermal insulation material 33 with low specific heat capacity and a phase change material 34 with high specific heat capacity, the thermal insulation effect of the thermal insulation material 33 can be ensured and the heat absorption capacity of the phase change material 34 can be improved. At the same time, since the temperature rise of the phase change material 34 with high specific heat capacity is low after absorbing heat, the phase change part also has a better thermal insulation effect.

[0132] In some embodiments, the thermal decomposition temperature of the thermal insulation material 33 is Tm≥1100°C.

[0133] The thermal decomposition temperature is the lowest temperature at which a material undergoes chemical changes after being heated. When this temperature is exceeded, the structure of the thermal insulation material 33 changes, causing its performance to deteriorate or fail. For battery cells 20 with high energy density, especially for battery cells 20 with energy density VED ≥ 650Wh / L, after thermal runaway occurs, the upper temperature limit inside the battery cell 20 generally does not exceed 1000°C. Using a thermal insulation material 33 with a thermal decomposition temperature of not less than 1100°C to make the thermal insulation pad 30 can further reduce the risk of damage to the thermal insulation pad 30, thereby improving the reliability of the thermal insulation pad 30.

[0134] In some embodiments, the thermal insulation pad 30 further includes an adhesive layer 35 , and the packaging layer 32 and the core material layer 31 are connected by the adhesive layer 35 .

[0135] The encapsulation layer 32 may be attached to the entire outer surface of the core material layer 31 , or may be attached to a local position of the core material layer 31 , and may be specifically designed according to the structure of the core material layer 31 .

[0136] In one embodiment provided in the present application, the battery device 100 includes a plurality of battery cells 20 and a plurality of thermal insulation pads 30, the plurality of battery cells 20 are arranged along the first direction Y, and the plurality of thermal insulation pads 30 are respectively arranged between adjacent battery cells 20. The thermal insulation pad 30 includes a core material layer 31 and a packaging layer 32. The core material layer 31 includes an insulating core plate, a flow channel is provided on the insulating core plate, and a phase change material 34 is filled in the flow channel. The thermal conductivity K1 of the insulating core plate is ≤0.04W / m·k, the specific heat capacity C1 is 0.2kJ / (kg·k)-1.4kJ / (kg·k), the thermal decomposition temperature is Tm≥1100°C, the thermal conductivity K2 of the phase change material 34 is ≥0.52W / m·k, and the specific heat capacity C2 is ≥4kJ / (kg·k). A pressure relief mechanism 24 is provided at one end of the battery cell 20, and a relatively large amount of phase change material 34 is provided at the core layer 31 near the pressure relief mechanism 24, and the volume ratio of the heat insulation core plate and the phase change material 34 in the core layer 31 is 3.5-8. The packaging layer 32 is attached to the surface of the heat insulation core plate and can seal the phase change material 34. The battery device 100 provided in the above embodiment has the following advantages: 1. The thermal insulation pad 30 includes a thermal insulation core plate structure. The thermal insulation core plate has a low thermal conductivity and a low specific heat capacity, which can effectively prevent heat conduction between the battery cells 20, thereby inhibiting the spread of heat in the battery device 100; 2. The thermal insulation pad 30 includes a phase change material 34. The phase change material 34 has a high thermal conductivity and a high specific heat capacity. The phase change material 34 quickly absorbs a large amount of heat through phase change, which can prevent the thermal insulation pad 30 from melting or structural collapse caused by local overheating, thereby ensuring the reliability of the thermal insulation pad 30; 3. By improving the setting position of the phase change material 34 and adjusting the proportion of the phase change material 34 in the thermal insulation pad 30, the thermal insulation performance and heat absorption capacity of the thermal insulation pad 30 can be balanced, so that the thermal insulation pad 30 can provide good thermal insulation effect and achieve effective temperature regulation.

[0137] An embodiment of the second aspect of the present application provides an electrical device, including the battery device 100 in the first aspect, and the battery device 100 is used to store or provide electrical energy.

[0138] The electric device provided in the embodiment of the present application improves the reliability and safety of the electric device by adopting the battery device 100 in the first aspect.

[0139] An embodiment of the third aspect of the present application provides an energy storage device, including the battery device 100 in the first aspect, and the battery device 100 is used to store or provide electrical energy.

[0140] The energy storage device provided in the embodiment of the present application improves the reliability and safety of the energy storage device by adopting the battery device 100 in the first aspect.

[0141] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A battery device, characterized in that: include: Multiple battery cells; At least one thermal insulation pad is arranged between adjacent battery cells, the thermal insulation pad comprises a core material layer and a packaging layer coated on the surface of the core material layer, the core material layer comprises a thermal insulation part and a phase change part, the thermal insulation part adopts a thermal insulation material, the phase change part adopts a phase change material, and the packaging layer can at least seal the phase change part.

2. The battery device according to claim 1, characterized in that A plurality of battery cells are arranged along a first direction, and the battery cells include two opposite ends in a second direction perpendicular to the first direction, and one end is provided with a pressure relief mechanism, and along the second direction, the core material layer includes a first portion close to the pressure relief mechanism and a second portion away from the pressure relief mechanism, and the mass of the phase change material contained in the first portion is greater than the mass of the phase change material contained in the second portion.

3. The battery device according to claim 1, characterized in that: The insulation part includes an insulation core board, on which a flow channel is provided. The flow channel penetrates the insulation core board along the thickness direction of the insulation core board, the phase change material is provided in the flow channel, and the encapsulation layer is attached to the outer surface of the insulation core board and covers the flow channel.

4. The battery device according to claim 3, characterized in that: The flow channel is a continuous structure.

5. The battery device according to claim 3, characterized in that: A plurality of battery cells are arranged along a first direction, and the battery cells include two opposite ends in a second direction perpendicular to the first direction, and a pressure relief mechanism is provided at one end thereof. Along the second direction, the core material layer includes a first portion close to the pressure relief mechanism and a second portion away from the pressure relief mechanism, and both the first portion and the second portion are provided with the flow channel, and the total volume of the flow channel of the first portion is greater than the total volume of the flow channel of the second portion.

6. The battery device according to claim 3, characterized in that: The phase change material is disposed on the outer edge of the thermal insulation core panel.

7. The battery device according to claim 1, characterized in that: The battery device includes a plurality of battery groups distributed along a third direction, each of the battery groups includes a plurality of battery cells arranged along a first direction, thermal insulation pads are arranged between the battery cells of adjacent battery groups, thermal insulation pads are arranged between adjacent battery cells in each battery group, and the first direction is perpendicular to the third direction.

8. The battery device according to any one of claims 1 to 7, characterized in that: Along the arrangement direction of the plurality of battery cells, the projected area of ​​the heat insulation portion on the battery cell is S1, the projected area of ​​the phase change portion on the battery cell is S2, and 3.5≤S1 / S2≤8.

9. The battery device according to claim 8, characterized in that: 1500mm 2 ≤S1≤8000mm 2 , and / or 400mm 2 ≤S2≤1000mm 2 .

10. The battery device according to any one of claims 1 to 7, characterized in that: The thermal conductivity of the thermal insulation material is K1, the thermal conductivity of the phase change material is K2, K2 / K1≥12; and / or K1≤0.04W / m·k, and / or K2≥0.52W / m·k.

11. The battery device according to any one of claims 1 to 7, characterized in that: The specific heat capacity of the thermal insulation material is C1, and / or the specific heat capacity of the phase change material is C2, C2 / C1≥3; and / or 0.2kJ / (kg·k)≤C1≤1.4kJ / (kg·k), and / or C2≥4kJ / (kg·k).

12. The battery device according to any one of claims 1 to 7, characterized in that: The thermal decomposition temperature of the thermal insulation material is Tm≥1100°C.

13. An electrical equipment, characterized in that: The battery device comprises the battery device according to any one of claims 1 to 12, wherein the battery device is used to store or provide electrical energy.

14. An energy storage device, characterized in that: The battery device comprises the battery device according to any one of claims 1 to 12, wherein the battery device is used to store or provide electrical energy.

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