Battery device and electric equipment

Abstract

The embodiment of the utility model provides a battery device and electric equipment, and relates to the technical field of batteries. The battery device comprises a shell, a battery monomer and a buffer pad, the buffer pad is mounted between two adjacent battery cells, the buffer pad comprises a memory alloy layer and an insulating layer, and the memory alloy layer is configured to be extruded and deformed by the adjacent battery cells under the condition that the memory alloy layer is in a first temperature range, and is recovered to a state before the memory alloy layer is extruded and deformed under the condition that the temperature is reduced to a second temperature range, the maximum value of the second temperature range is smaller than the minimum value of the first temperature range; the insulating layer at least wraps the memory alloy layer, and the memory alloy layer is provided with an opening. According to the battery device, the memory alloy is used for resisting expansion of the battery monomers, and the possibility of thinning after multiple compression deformation and deformation recovery is lower than that of an existing buffer cushion, so that the possibility of generating a gap between two adjacent battery monomers is reduced, and the safety and the reliability of the battery device are improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a battery device and an electrical appliance. Background Technology

[0002] The battery assembly includes a housing and individual battery cells installed inside the housing. To buffer expansion or impact, buffer pads are usually placed between adjacent battery cells for spacing.

[0003] Existing buffer pads are difficult to fully rebound after repeated compression, causing them to thin and creating gaps between adjacent battery cells, thus affecting the safety and reliability of the battery device. Therefore, improving the reliability of buffer pads is a research direction in battery technology. Utility Model Content

[0004] This application provides a battery device and an electrical appliance that can improve the reliability of a cushioning pad.

[0005] In a first aspect, embodiments of this application provide a battery device, including a housing, a plurality of battery cells, and at least one buffer pad, wherein the plurality of battery cells are installed within the housing; the buffer pad is installed between two adjacent battery cells, and the buffer pad includes a shape memory alloy layer and an insulating layer, wherein the shape memory alloy layer is configured to be deformed by compression from adjacent battery cells under a first temperature range, and to return to its state before being deformed under compression when the temperature drops to a second temperature range, wherein the maximum value of the second temperature range is less than the minimum value of the first temperature range; along the arrangement direction of two battery cells adjacent to the buffer pad, the shape memory alloy layer has a first surface and a second surface facing away from each other, the insulating layer covers at least the first surface and the second surface, and the shape memory alloy layer has a plurality of openings penetrating the first surface and / or the second surface.

[0006] The above technical solution utilizes shape memory alloys to resist the expansion of individual battery cells. After being deformed by the expansion of the battery cells, the shape memory alloy undergoes a phase change under temperature stimulation, achieving shape recovery and continuing to support the battery cells. Furthermore, the shape memory alloy is less likely to thin after multiple compression and recovery deformations compared to existing buffer pads, thus reducing the possibility of gaps between adjacent battery cells and improving the safety and reliability of the battery device. Multiple openings are formed in the shape memory alloy layer, which facilitates the collapse deformation of the shape memory alloy layer during battery cell expansion, thus counteracting the expansion. An insulating layer covers at least the first and second surfaces, separating the shape memory alloy layer from the battery cells and reducing the risk of short circuits in the battery cells.

[0007] In some embodiments of this application, the plurality of openings are arranged in a honeycomb pattern.

[0008] By adopting the above technical solution, the openings are designed to be arranged in a honeycomb pattern. The honeycomb structure can better absorb and disperse the expansion force of the battery cells, thereby improving the structural stability and safe life of the battery device.

[0009] In some embodiments of this application, the ratio of the thickness a of the hole wall around the opening to the thickness b of the shape memory alloy layer is in the range of (1 / 500) ≤ (a / b) ≤ (1 / 10).

[0010] By adopting the above technical solution, the ratio of the hole wall thickness to the shape memory alloy layer thickness is designed to be within the above range, which is conducive to the deformation of the honeycomb hole wall and enables the honeycomb hole wall to effectively absorb mechanical energy when the battery cell expands.

[0011] In some embodiments of this application, the ratio of a to b is in the range of (1 / 300) ≤ (a / b) ≤ (1 / 20).

[0012] By adopting the above technical solution, the ratio of the hole wall thickness to the thickness of the shape memory alloy layer is designed to be within the above range, which is conducive to the deformation of the honeycomb hole wall, so that the honeycomb hole wall can better absorb mechanical energy when the battery cell expands, and it is also more conducive to the shape memory alloy layer returning to its state before deformation.

[0013] In some embodiments of this application, the value of 'a' ranges from 0.05 mm to 0.2 mm.

[0014] By adopting the above technical solution, the hole wall thickness is designed to the above value, so that the hole wall has sufficient structural strength to maintain honeycomb stability, and at the same time, it can deform in the early stage of battery cell expansion, thereby absorbing impact mechanical energy in a timely and efficient manner.

[0015] In some embodiments of this application, the shape formed by the hole wall around the opening is a regular polygon, and the ratio of the thickness a of the hole wall around the opening to the side length c of the regular polygon is in the range of (1 / 200) ≤ (a / c) ≤ (1 / 10).

[0016] By adopting the above technical solution and using the above ratio for the hole wall thickness and side length, the structural stability of the shape memory alloy layer is improved, and it can effectively absorb energy through orderly deformation under pressure, reducing the possibility of stress concentration.

[0017] In some embodiments of this application, the ratio of a to c is in the range of (1 / 150) ≤ (a / c) ≤ (1 / 30).

[0018] By adopting the above technical solution and using the above ratio for the hole wall thickness and side length, the shape memory alloy layer has better compressive strength and stability, and the honeycomb structure can absorb energy through overall deformation, thus taking into account both buffering and support functions.

[0019] In some embodiments of this application, the value of c ranges from 3 mm to 6 mm.

[0020] By adopting the above technical solution, within the range of side length c, sufficient deformation space can be provided for the expansion of the battery cell, while the honeycomb structure has sufficient cell density, thereby better dispersing stress.

[0021] In some embodiments of this application, the shape memory alloy layer is a copper-based alloy layer or a nickel-titanium-based alloy layer.

[0022] Using the above technical solution, the copper-based or nickel-titanium-based shape memory alloy layer has significant phase change characteristics and can provide sufficient recovery driving force at low temperature, so that the shape memory alloy layer can better recover its shape before deformation at the second temperature, in order to resist the expansion cycle of the subsequent battery cell.

[0023] In some embodiments of this application, the material hardness of the insulating layer is greater than that of the shape memory alloy layer.

[0024] By adopting the above technical solution, the material hardness of the insulating layer is greater than that of the shape memory alloy layer, which reduces the possibility that the shape memory alloy layer may puncture the battery cell due to excessive local pressure when under pressure, leading to insulation failure of the battery cell.

[0025] In some embodiments of this application, the insulating layer includes at least one of a mica layer and a ceramic layer.

[0026] Using the above technical solution, the mica layer and ceramic layer have good hardness, insulation and heat resistance, and can provide stable protection and constraint for the shape memory alloy layer under charge and discharge conditions.

[0027] In some embodiments of this application, the buffer pad further includes an encapsulation layer wrapped around the insulating layer, the encapsulation layer being connected to two adjacent battery cells.

[0028] By adopting the above technical solution, the insulation layer is wrapped with an encapsulation layer, which improves the structural integrity of the buffer pad, facilitates the assembly of the buffer pad, and enhances the stability of the internal structure of the buffer pad.

[0029] Secondly, embodiments of this application provide an electrical device including a battery device as described in any of the above technical solutions, wherein the battery device is used to provide electrical energy. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of the electrical equipment provided in the embodiments of this application;

[0032] Figure 2 This is a schematic diagram of the structure of the battery device provided in the embodiments of this application;

[0033] Figure 3 This is a schematic diagram of the structure of the buffer pad provided in an embodiment of this application;

[0034] Figure 4 for Figure 3 AA section diagram;

[0035] Figure 5 This is a schematic diagram of the shape memory alloy layer provided in an embodiment of this application;

[0036] Figure 6 for Figure 5 Enlarged view of part d.

[0037] The reference numerals in the accompanying drawings for the specific embodiments are as follows:

[0038] 1000, vehicles;

[0039] 100. Battery device;

[0040] 10. Shell;

[0041] 1. Part One;

[0042] 2. Part Two;

[0043] 20. Battery cell;

[0044] 30. Buffer pad; 31. Shape memory alloy layer; 311. First surface; 312. Second surface; 313. Opening; 32. Insulating layer; 33. Encapsulation layer;

[0045] 200. Controller;

[0046] 300. Motor;

[0047] X, the first direction. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0050] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0051] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0052] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, H and / or B can represent: H existing alone, H and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0053] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0054] In this application, "multiple" means two or more (including two).

[0055] The battery device includes a housing and multiple battery cells housed within the housing. To buffer and absorb the expansion forces of the battery cells during charging and discharging, buffer pads are placed between adjacent battery cells to improve the structural stability and safety of the battery device during long-term cyclic use.

[0056] Existing buffer pads are mostly made of elastic materials such as rubber or polyurethane. Although their strength can meet the requirements after optimization, they are difficult to fully recover to their initial thickness after being compressed and deformed repeatedly by the expansion force of the battery cells, resulting in an overall thinning of the buffer pad. This causes the gaps between adjacent battery cells that were originally filled by the buffer pad to widen, and the battery cells to loosen within the casing, affecting the long-term safety, reliability, and service life of the battery device.

[0057] Therefore, how to reduce the possibility of the buffer pad thinning after multiple deformations is an important issue in the research and development of battery devices and related components.

[0058] In view of this, this application provides a technical solution that replaces the original elastic material with a shape memory alloy material, and utilizes the characteristic of shape memory alloy material to recover deformation, thereby solving the above-mentioned technical problem.

[0059] The battery cells described in the embodiments of this application are applicable to batteries and electrical devices that use batteries.

[0060] Electrical equipment can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical equipment.

[0061] For ease of explanation, the following embodiments use a vehicle as an example of electrical equipment.

[0062] Combined with appendix Figure 1As shown, vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside vehicle 1000, and the battery device 100 can be located at the bottom, front, or rear of vehicle 1000. The battery device 100 can be used to power vehicle 1000; for example, the battery device 100 can serve as the operating power source for vehicle 1000. Vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, to meet the power needs of vehicle 1000 during starting, navigation, and driving.

[0063] In some embodiments, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0064] Combined with appendix Figure 2-4 As shown, this application provides a battery device 100, including a housing 10, a plurality of battery cells 20 and at least one buffer pad 30. The plurality of battery cells 20 are installed inside the housing 10; the buffer pad 30 is installed between two adjacent battery cells 20. The buffer pad 30 includes a shape memory alloy layer 31, which is configured to be deformed by the adjacent battery cells 20 under a first temperature range and to return to the state before being deformed under a second temperature range. The maximum value of the second temperature range is less than the minimum value of the first temperature range.

[0065] The battery device 100 mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells 20, which are connected in series, parallel, or mixed connections via a busbar.

[0066] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells 20; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells 20 together to form a single module. As an example, a battery module can be formed by bundling multiple battery cells 20 together with cable ties.

[0067] In some embodiments, the battery device 100 may be a battery pack, which includes a housing 10 and one or more battery cell assemblies housed within the housing 10.

[0068] In some embodiments, the battery device 100 may also refer to an energy storage device, which includes a housing 10, and at least one side of the housing 10 has a door. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0069] The housing 10 provides a receiving space for the battery cell 20, and the housing 10 can adopt various structures. In some embodiments, the housing 10 may include a first part 1 and a second part 2, the first part 1 and the second part 2 overlapping each other, and the first part 1 and the second part 2 together define a receiving space for receiving the battery cell 20.

[0070] In this design, both the first part 1 and the second part 2 can be hollow structures with one open end, with the second part 2 covering the open side of the first part 1 so that the first part 1 and the second part 2 together define the receiving space; alternatively, the second part 2 can be a plate-like structure, the first part 1 can be a hollow structure with one open side, and the open side of the second part 2 can cover the open side of the first part 1. Of course, the shell 10 formed by the first part 1 and the second part 2 can be of various shapes, such as a cylinder, a cuboid, etc.

[0071] In some embodiments, the housing 10 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that the interior of the housing 10 forms an enclosed space to accommodate the battery cell assembly.

[0072] In some embodiments, the housing 10 may be part of the chassis structure of the vehicle 1000. For example, the top cover of the housing 10 may be at least part of the floor of the vehicle 1000, or the frame of the housing 10 may be at least part of the crossbeams and longitudinal beams of the vehicle 1000.

[0073] The battery cell 20 mentioned in the embodiments of this application may include an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode, a negative electrode, and a separator. The battery cell 20 mainly operates by the movement of metal ions between the positive and negative electrode. The positive electrode includes a positive current collector and a positive active material layer, the positive active material layer being coated on the surface of the positive current collector; the positive current collector includes a positive electrode coating area and a positive electrode tab connected to the positive electrode coating area, the positive electrode coating area being coated with the positive active material layer, and the positive electrode tab not being coated with the positive active material layer.

[0074] In this embodiment, the buffer pad 30 is installed between two adjacent battery cells 20 and is used to resist the expansion of the battery cells 20. The buffer pad 30 includes a memory alloy layer 31. The material of the memory alloy layer 31 is a shape memory alloy. A shape memory alloy is a type of metal material with a shape memory effect, which can completely recover from its current deformed state to its preset original shape under specific conditions.

[0075] In this embodiment, the shape memory alloy layer 31 is configured to be deformed by the adjacent battery cell 20 when it is in a first temperature range. This means that the battery cell 20 expands during the charging and discharging process. At this time, the temperature of the battery cell 20 is higher than the room temperature, causing the temperature of the shape memory alloy layer 31 to rise to the first temperature range.

[0076] The first temperature range depends on the room temperature, and is typically 10°C to 50°C above the room temperature. For example, if the room temperature is 30°C, the first temperature range could be 40°C to 80°C.

[0077] When the shape memory alloy layer 31 is in the second temperature range, it means that the battery cell 20 is not charged or discharged, and the temperature of the entire battery device 100 is reduced to room temperature or below room temperature. At this time, the shape memory alloy layer 31 under low temperature stimulation can recover to its state before deformation.

[0078] Taking a room temperature of 30°C as an example, the second temperature range can be from 0°C to 30°C.

[0079] Specifically, when the battery device 100 is working, its internal temperature rises and falls within a first temperature range, and the shape memory alloy layer 31 is in its high-temperature stable phase state. At this time, the battery cell 20 expands due to heat, generating enormous pressure. This pressure directly induces a phase change within the material, causing the shape memory alloy layer 31 to deform, thereby absorbing the expansion energy of the battery cell 20 and providing a continuous buffer space for the battery cell 20.

[0080] When the battery device 100 stops working and the temperature drops to room temperature (or under external low-temperature conditions), the stress exerted by the battery cell 20 on the shape memory alloy layer 31 is also relieved. After the stress and temperature return to their initial state, the shape memory alloy, with its inherent reversible phase transition characteristics, automatically undergoes a reverse phase transition, restoring its original geometry before deformation, and providing rigid support for the cooled and contracted battery cell 20 again.

[0081] In this way, the deformation of the shape memory alloy layer 31 can be used to resist the expansion of the battery cell 20, and the shape memory alloy layer 31 can be used to undergo a phase change under stimulation to achieve shape recovery, thus continuing to support the battery cell 20. Moreover, the shape memory alloy is less likely to become thinner after multiple compression deformations and recovery deformations than the existing buffer pad 30, thereby reducing the possibility of gaps between two adjacent battery cells 20 and improving the safety and reliability of the battery device 100.

[0082] In some examples, optionally, along the arrangement direction of two battery cells 20 adjacent to the buffer pad 30, the shape memory alloy layer 31 has a first surface 311 and a second surface 312 facing away from each other, and the shape memory alloy layer 31 is provided with a plurality of openings 313 penetrating through the first surface 311 and / or the second surface 312.

[0083] The above technical solutions include at least three implementation methods. The first method is that the opening 313 only penetrates the first surface 311. The second method is that the opening 313 only penetrates the second surface 312. The third method is that the opening 313 penetrates both the first surface 311 and the second surface 312.

[0084] Compared to the first and second methods, the third method is most conducive to the deformation of the shape memory alloy layer 31.

[0085] The through direction of the opening 313 can be directly along the arrangement direction of the first surface 311 to the second surface 312 (the first direction X in the figure), or it can be a direction that intersects with but is not perpendicular to the first direction X. This embodiment will not describe this in detail.

[0086] Multiple openings 313 penetrating the first surface 311 and / or the second surface 312 are provided on the shape memory alloy layer 31, which can facilitate the collapse deformation of the shape memory alloy layer 31 when the battery cell 20 expands, thereby offsetting the expansion of the battery cell 20.

[0087] Combined with appendix Figure 5 As shown, in some examples, the multiple openings 313 are optionally arranged in a honeycomb pattern.

[0088] Multiple openings 313 are arranged in a honeycomb pattern, which means that multiple openings 313 are arranged in a plane to imitate the geometric features of a natural honeycomb, forming a continuous and regular mesh of holes. The shape of the openings 313 can be a polygonal structure such as hexagonal or quadrilateral.

[0089] In this way, the entire shape memory alloy layer 31 forms a honeycomb structure. When subjected to the expansion pressure of the battery cell 20, the expansion pressure of the battery cell 20 is converted into compression of the honeycomb structure pore walls. The deformation of the honeycomb structure pore walls absorbs and buffers the pressure, which can better suppress the overall swelling of the battery and improve the structural stability and service life of the battery device 100.

[0090] In addition, the synergistic effect of the individual openings 313 during deformation of the honeycomb structure disperses stress throughout the entire mesh skeleton, reducing the possibility of stress concentration.

[0091] Combined with appendix Figure 4 and 6 As shown, in some examples, optionally, the ratio of the thickness a of the hole wall around the opening 313 to the thickness b of the shape memory alloy layer 31 is in the range of (1 / 500) ≤ (a / b) ≤ (1 / 10).

[0092] The thickness direction of the shape memory alloy layer 31 is set along the first direction X in the figure. Taking the through direction of the opening 313 as an example, which is along the first direction X in the figure, the thickness of the hole wall of the opening 313 is set along a direction that is perpendicular to the first direction X and parallel to the first surface 311.

[0093] The purpose of limiting the ratio of the hole wall thickness a around the opening 313 to the overall thickness b of the shape memory alloy layer 31 within the above range is to achieve a balance between hole wall stiffness and flexibility.

[0094] When the ratio of a to b is not less than (1 / 500), the hole wall has a certain structural strength to maintain the overall stability of the shape memory alloy layer 31.

[0095] When the ratio of a to b is not higher than (1 / 10), the pore wall has a certain deformation capacity, which allows it to absorb the expansion force by bending deformation when subjected to the expansion and compression of the battery cell 20.

[0096] This not only facilitates the deformation of the honeycomb pore walls, enabling them to effectively absorb mechanical energy when the battery cell 20 expands, but also allows the shape memory alloy layer 31 to have better stability.

[0097] In some examples, the ratio of a to b may optionally be in the range of (1 / 300) ≤ (a / b) ≤ (1 / 20).

[0098] The above ratio range is a further narrowing of the ratio of a to b. For example, the ratio of a to b can be (1 / 300), (1 / 200), (1 / 100), (1 / 50), and (1 / 20), etc.

[0099] Experiments have shown that when the ratio of a to b is between (1 / 300) and (1 / 20), it not only facilitates the deformation of the honeycomb pore wall, allowing the honeycomb pore wall to better absorb mechanical energy when the battery cell 20 expands, but also makes it easier for the shape memory alloy layer 31 to recover to its state before deformation.

[0100] In some examples, the numerical range of a is optionally 0.05 mm to 0.2 mm.

[0101] The value range of 'a' can be 0.05mm, 0.08mm, 0.1mm, 0.15mm, and 0.2mm, etc., which will not be listed one by one in this embodiment.

[0102] The hole wall thickness of the opening 313 is designed to the above value so that the hole wall has sufficient structural strength to maintain the stability of the honeycomb, while it can deform in the early stage of the expansion of the battery cell 20, so as to absorb the impact mechanical energy in a timely and efficient manner.

[0103] Combined with appendix Figure 6 As shown, in some examples, optionally, the shape enclosed by the hole wall around the opening 313 is a regular polygon, and the ratio of the thickness a of the hole wall around the opening 313 to the side length c of the regular polygon is in the range of (1 / 200) ≤ (a / c) ≤ (1 / 10).

[0104] Regular polygons can be equilateral triangles, squares, regular hexagons, regular octagons, etc., and this embodiment will not list them in detail.

[0105] Setting the ratio of the hole wall thickness 'a' to the polygonal hole wall side length 'c' within the above range takes into account both the strength and buffering performance of the honeycomb structure.

[0106] When the ratio of a to c is not less than (1 / 200), the hole wall of the opening 313 has a certain rigidity and strength, which can reduce the possibility of local collapse of the hole wall when subjected to expansion force and improve the stress diffusion ability.

[0107] When the ratio of a to c is not higher than (1 / 10), the hole wall of a single hole 313 can undergo sufficient and coordinated bending deformation when subjected to the squeezing action generated by the expansion of the battery.

[0108] In some examples, the ratio of a to c may optionally be in the range of (1 / 150) ≤ (a / c) ≤ (1 / 30).

[0109] The range of the ratio of a to c mentioned above is a further narrowing of (1 / 200) ≤ (a / c) ≤ (1 / 10).

[0110] Specifically, the ratio of a to c can be (1 / 150), (1 / 100), (1 / 80), (1 / 50), and (1 / 30), etc.

[0111] By using the above-mentioned ratio between the hole wall thickness and the side length, the compressive strength and stability of the shape memory alloy layer 31 are further improved, and the honeycomb structure can absorb energy through overall deformation, thus better balancing the buffering and supporting functions.

[0112] In some embodiments of this application, the value of c ranges from 3 mm to 6 mm.

[0113] The side length c can be 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, or 6mm, etc. Of course, the specific value can be determined according to the specifications of the battery device 100.

[0114] Within the aforementioned range of side length c, sufficient deformation space can be provided for the expansion of the battery cell 20, while also ensuring that the honeycomb structure has sufficient cell density, thereby better dispersing stress.

[0115] In some examples, the shape memory alloy layer 31 may optionally be a copper-based alloy layer or a nickel-titanium-based alloy layer.

[0116] In this embodiment, the copper-based alloy layer refers to an alloy material with copper as the basic element and containing specific elements such as zinc, aluminum, and tin.

[0117] The nickel-titanium based alloy layer in this embodiment refers to an alloy material composed of nickel and titanium elements in a near-equal atomic ratio, and may contain small amounts of other elements.

[0118] It should be noted that the shape memory effect of the copper-based or nickel-titanium-based shape memory alloys used in this application does not rely on the austenite-martensite phase transformation mechanism commonly found in steel materials.

[0119] In this embodiment, the shape memory alloy layer 31 achieves its shape memory function through a reversible thermoelastic phase transition. Specifically, in the first temperature range (higher temperature), the alloy is in the parent phase state, at which point the material is relatively soft and easily undergoes plastic deformation and compression under external force.

[0120] When the temperature drops to the second temperature range (lower temperature), a phase transformation occurs inside the alloy, and the material is able to overcome the yield stress and automatically recover to its original shape before being compressed.

[0121] The aforementioned characteristics enable the shape memory alloy layer 31 of this embodiment to repeatedly perform energy absorption and recovery functions during battery thermal management cycles in order to resist subsequent expansion cycles of the battery cells 20.

[0122] In some examples, the buffer pad 30 may optionally include an insulating layer 32, and along the arrangement direction of two battery cells 20 adjacent to the buffer pad 30, the shape memory alloy layer 31 has a first surface 311 and a second surface 312 facing away from each other, and the insulating layer 32 covers at least the first surface 311 and the second surface 312.

[0123] Combined with appendix Figure 4 As shown, the insulating layer 32 covers at least the first surface 311 and the second surface 312, which means that the insulating layer 32 in this embodiment can be attached only to the first surface 311 and the second surface 312, and completely cover the first surface 311 and the second surface 312.

[0124] Of course, in some embodiments, the insulating layer 32 can also be installed on the other surfaces of the shape memory alloy layer 31 besides the first surface 311 and the second surface 312. However, this method is more complicated and more expensive than simply attaching the insulating layer 32 to the first surface 311 and the second surface 312.

[0125] Moreover, the insulating layer 32 mainly serves an insulating function, so the insulating layer 32 can be provided only on the first surface 311 and the second surface 312 that come into contact with the battery cell 20.

[0126] The insulating layer 32 can separate the shape memory alloy layer 31 from the battery cell 20, thereby reducing the risk of short circuit in the battery cell 20.

[0127] In some examples, the material hardness of the insulating layer 32 is optionally greater than that of the shape memory alloy layer 31.

[0128] Hardness is a mechanical property indicator that measures a material’s ability to resist the indentation of its surface by an external object.

[0129] The reason why the material hardness of the insulating layer 32 is greater than that of the shape memory alloy layer 31 is that the shape memory alloy layer 31 in this embodiment has a honeycomb structure and the walls of the honeycomb holes are relatively thin. When deformation occurs, the local pressure is too high and the battery cell 20 is punctured.

[0130] Therefore, in order to reduce the possibility that the shape memory alloy layer 31 may puncture the battery cell 20 due to excessive local pressure when under pressure, thus causing the insulation of the battery cell 20 to fail, the hardness of the insulation layer 32 is designed to be greater in this embodiment.

[0131] In addition, the high hardness of the insulating layer 32 can protect the cushioning pad 30 from damage during assembly and use, thereby improving the structural and functional stability of the cushioning pad 30.

[0132] In some examples, the insulating layer 32 may optionally include at least one of a mica layer and a ceramic layer.

[0133] The insulating layer 32 can be a single mica layer, a single ceramic layer, or a combination of both.

[0134] The mica and ceramic layers have good hardness, insulation and heat resistance, which can provide stable protection and constraint for the shape memory alloy layer 31 under charge and discharge conditions.

[0135] Combined again with the appendix Figure 4 As shown, in some examples, the buffer pad 30 may optionally include an encapsulation layer 33 wrapped around the insulating layer 32, the encapsulation layer 33 being connected to two adjacent battery cells 20.

[0136] The encapsulation layer 33 completely covers the shape memory alloy layer 31 and the insulating layer 32. The material of the encapsulation layer 33 can be aluminum-plastic film, polymer plastic film, multilayer composite insulating film, etc., which will not be listed one by one in this embodiment.

[0137] By using the encapsulation layer 33 to wrap the insulating layer 32, the surface of the unencapsulated shape memory alloy layer 31 and the surface of the insulating layer 32 are completely wrapped, which can improve the structural integrity of the buffer pad 30. This not only facilitates the assembly of the buffer pad 30, but also improves the stability of the internal structure of the buffer pad 30.

[0138] Combined again with the appendix Figure 1 As shown in the figure, this application embodiment also provides an electrical device, including a battery device 100 of any of the above technical solutions, the battery device 100 being used to provide electrical energy.

[0139] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application.

[0140] Please see the appendix Figure 2-6As shown, this application embodiment provides a battery device 100, including a housing 10, a plurality of battery cells 20, and at least one buffer pad 30. The plurality of battery cells 20 are installed inside the housing 10; the buffer pad 30 is installed between two adjacent battery cells 20, and the buffer pad 30 includes a shape memory alloy layer 31. The shape memory alloy layer 31 is configured to be deformed by compression from adjacent battery cells 20 under a first temperature range, and to return to its state before being deformed under a second temperature range, wherein the maximum value of the second temperature range is less than the minimum value of the first temperature range. Along the arrangement direction of two battery cells 20 adjacent to the buffer pad 30, the shape memory alloy layer 31 has a first surface 311 and a second surface 312 facing away from each other, and the shape memory alloy layer 31 is provided with a plurality of openings 313 penetrating the first surface 311 and the second surface 312. The plurality of openings 313 are arranged in a honeycomb pattern. The ratio of the thickness a of the hole wall around the opening 313 to the thickness b of the shape memory alloy layer 31 is in the range of (1 / 500) ≤ (a / b) ≤ (1 / 10). The thickness 'a' of the wall surrounding the opening 313 ranges from 0.05 mm to 0.2 mm. The shape enclosed by the wall surrounding the opening 313 is a regular polygon, and the ratio of the wall thickness 'a' to the side length 'c' of the regular polygon ranges from (1 / 200) ≤ (a / c) ≤ (1 / 10). The side length 'c' of the regular polygon ranges from 3 mm to 6 mm. The shape memory alloy layer 31 is a copper-based alloy layer or a nickel-titanium-based alloy layer. The buffer pad 30 also includes an insulating layer 32. Along the arrangement direction of two adjacent battery cells 20, the shape memory alloy layer 31 has a first surface 311 and a second surface 312 facing away from each other, and the insulating layer 32 at least covers the first surface 311 and the second surface 312. The material hardness of the insulating layer 32 is greater than that of the shape memory alloy layer 31. The insulating layer 32 includes a mica layer or a ceramic layer. The buffer pad 30 also includes an encapsulation layer 33 wrapped around the insulating layer 32, and the encapsulation layer 33 is connected to two adjacent battery cells 20.

[0141] Secondly, embodiments of this application provide an electrical device including a battery device 100 as described in any of the above technical solutions, wherein the battery device 100 is used to provide electrical energy.

[0142] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this 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 described in the foregoing embodiments, or make equivalent substitutions for the intermediate technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A battery device, characterized by, include: case; Multiple battery cells, wherein the multiple battery cells are installed inside the housing; as well as At least one buffer pad is installed between two adjacent battery cells. The buffer pad includes a shape memory alloy layer and an insulating layer. The shape memory alloy layer is configured to be deformed by the adjacent battery cells under a first temperature range and to return to its state before being deformed under a temperature drop to a second temperature range, where the maximum value of the second temperature range is less than the minimum value of the first temperature range. Along the arrangement direction of two battery cells adjacent to the buffer pad, the shape memory alloy layer has a first surface and a second surface facing away from each other, the insulating layer covers at least the first surface and the second surface, and the shape memory alloy layer has a plurality of openings penetrating the first surface and / or the second surface.

2. The battery device according to claim 1, characterized by The multiple openings are arranged in a honeycomb pattern.

3. The battery device of claim 2, wherein, The ratio of the thickness a of the circumferential hole wall to the thickness b of the shape memory alloy layer is in the range of (1 / 500) ≤ (a / b) ≤ (1 / 10).

4. The battery device of claim 3, wherein The ratio of a to b is in the range of (1 / 300) ≤ (a / b) ≤ (1 / 20).

5. The battery device of claim 4, wherein, The value of 'a' ranges from 0.05 mm to 0.2 mm.

6. The battery device according to any one of claims 1-5, characterized in that, The shape enclosed by the circumferential wall of the opening is a regular polygon, and the ratio of the thickness a of the wall around the opening to the side length c of the regular polygon is: (1 / 200) ≤ (a / c) ≤ (1 / 10).

7. The battery device of claim 6, wherein The ratio of a to c is in the range of (1 / 150) ≤ (a / c) ≤ (1 / 30).

8. The battery device of claim 7, wherein, The value of c ranges from 3 mm to 6 mm.

9. The battery device according to any one of claims 1 to 5, wherein The shape memory alloy layer is a copper-based alloy layer or a nickel-titanium-based alloy layer.

10. The battery device according to any one of claims 1 to 5, wherein The material hardness of the insulating layer is greater than that of the shape memory alloy layer.

11. The battery device of claim 10, wherein, The insulating layer includes at least one of a mica layer and a ceramic layer.

12. The battery device according to any one of claims 1 to 5, wherein The buffer pad also includes an encapsulation layer that wraps around the insulating layer, and the encapsulation layer is connected to two adjacent battery cells.

13. An electrical device, characterized by Includes the battery device as described in any one of claims 1-12, the battery device being used to provide electrical energy.

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