Battery pack and electric equipment

Abstract

The invention relates to a battery pack and electric equipment, and relates to the technical field of batteries, and the battery pack comprises a battery cell, a busbar and two pouring sealant layers. The battery cell is provided with a pole piece and a tab connected to the pole piece; the busbar is connected to one end, far away from the pole piece, of the tab; the first adhesive layer is encapsulated between the busbar and the pole piece and covers the connecting part of the pole piece and the tab, the second adhesive layer is encapsulated between the busbar and the first adhesive layer and covers the connecting part of the busbar and the tab, the elastic modulus of the first adhesive layer is a, the elastic modulus of the second adhesive layer is b, and a is less than b. Through gradient distribution of elastic modulus, the first adhesive layer forms flexible buffer in the tab area to adapt to expansion deformation of the pole piece, and the second adhesive layer forms rigid support to absorb impact load, so that the structural strength and reliability of the tab connection part are improved to a certain extent, and the safety performance of the battery pack under the conditions of falling and vibration is improved.

Description

Technical Field

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

[0002] Currently, electric vertical takeoff and landing (eVTOL) aircraft operate in complex high-altitude environments, which places more stringent requirements on the mechanical strength and safety performance of the power battery modules. In particular, during drop tests, it is necessary to ensure that the modules still have reliable protective performance when subjected to impact.

[0003] However, existing pouch battery modules still face significant challenges in the protection design of the electrode lead-out area. Because the electrode lead-out area typically integrates various structural components such as busbars and tabs, while it may meet the protection and cushioning requirements during drop tests, it is actually prone to damage to the tabs during battery use, thus affecting battery performance and safety. Summary of the Invention

[0004] This application provides a battery pack and an electrical device to at least partially solve the above-mentioned technical problems.

[0005] To achieve the above objectives, according to a first aspect of this application, a battery pack is provided, comprising: A battery cell includes an electrode and a tab, wherein the tab is connected to the electrode; A busbar is connected to the end of the tab furthest from the electrode plate; A first adhesive layer is applied between the busbar and the electrode, and the first adhesive layer covers the connection between the electrode and the tab. A second adhesive layer is formed between the manifold and the first adhesive layer, and the second adhesive layer covers the connection between the manifold and the electrode tab; wherein, The elastic modulus of the first adhesive layer is a, and the elastic modulus of the second adhesive layer is b, where a < b.

[0006] By adopting the above technical solution, a gradient buffer structure is formed by setting two layers of adhesive with different elastic moduli between the electrode and the busbar. The first adhesive layer has a lower elastic modulus and provides flexible buffering, allowing it to deform dynamically during electrode expansion or cycling, thus keeping the connection between the electrode tab and the electrode stable and less prone to breakage. The second adhesive layer has a higher elastic modulus and higher hardness, providing rigid support during drops or mechanical impacts, preventing breakage at the connection between the busbar and the electrode tab. The synergistic effect of the first and second adhesive layers achieves both dynamic protection and impact buffering at the electrode tab connection, significantly improving the reliability of the battery pack's electrode tabs under drop impacts and long-term use conditions.

[0007] In one embodiment, the battery pack further includes a top seal, the electrode is located within the top seal, and the electrode tab includes a first tab and a second tab; wherein, The first ear portion is embedded in the top sealing portion and connected to the electrode sheet, and the first adhesive layer covers the top sealing portion; The second ear is connected to the end of the first ear away from the electrode, the second ear is exposed outside the top seal and connected to the busbar, and the second adhesive layer covers the second ear.

[0008] By adopting the above technical solution, the electrode tabs are divided into a first tab embedded in the top seal and an exposed second tab. The first tab is covered by a flexible first adhesive layer, which can provide flexible follow-up protection when the cell expands. The second tab is covered by a second adhesive layer, forming a rigid protective layer in the busbar connection area, enhancing the impact resistance of the exposed section of the electrode tab. This structure effectively protects different functional areas of the electrode tabs in separate zones, making the internal flexible buffer and the external structural strength complementary, thereby improving the overall durability and drop resistance of the cell packaging area.

[0009] In one embodiment, the first adhesive layer is a flexible adhesive; and / or, the second adhesive layer is a high-strength adhesive.

[0010] By adopting the above technical solution, by designing the first adhesive layer as flexible adhesive and the second adhesive layer as high-strength adhesive, the deformation of the battery cell during normal charge and discharge cycles can be absorbed and buffered by the flexible adhesive layer, while the high-strength adhesive layer provides rigid support when subjected to external impact, thereby achieving a multi-stage protection effect that combines flexibility and rigidity, and improving the reliability of the electrode welding part and the module's resistance to mechanical impact.

[0011] In one embodiment, the first adhesive layer is made of polyimide or silicone; and / or, the second adhesive layer is made of epoxy resin or polyurethane.

[0012] By adopting the above technical solution, the first adhesive layer, made of polyimide or silicone, possesses excellent flexibility, high-temperature resistance, and dielectric properties, maintaining stable adhesion even when the electrode expands and deforms. The second adhesive layer, made of epoxy resin or polyurethane, possesses high strength and excellent impact energy absorption performance, rapidly dispersing impact energy during drop conditions. Through matching material properties, comprehensive protection of the high-altitude flight battery module is achieved under multiple coupled conditions such as temperature, stress, and impact.

[0013] In one embodiment, the thickness of the first adhesive layer in the height direction of the battery cell is H1, and the thickness of the second adhesive layer in the height direction of the battery cell is H2, wherein H1 < H2.

[0014] By adopting the above technical solution, and setting the thickness H1 of the first adhesive layer to be less than the thickness H2 of the second adhesive layer, a thickness gradient distribution from flexible to rigid is formed, allowing the stress in the tab connection area to transition layer by layer, avoiding stress concentration caused by abrupt changes in stiffness. This thickness design further improves the buffering and coordination performance of the adhesive layers, ensuring structural stability and lifespan under different loads such as drops, vibrations, and cyclic expansion.

[0015] In one embodiment, the battery pack further includes a housing, in which a plurality of battery cells are arranged along the length of the housing, and the first adhesive layer and the second adhesive layer are both filled between the plurality of battery cells and the inner top wall of the housing.

[0016] By adopting the above technical solution, a first adhesive layer and a second adhesive layer are simultaneously placed between the battery cell and the casing to construct a module-level integrated potting system. This system can simultaneously absorb impact energy between battery cells and between the battery cell and the casing, forming a multi-layered buffer protection network. This structure can prevent damage to the tabs and busbars under drop impacts, effectively improving the overall impact resistance and service life of the battery pack.

[0017] In one embodiment, the housing is made of a composite of para-aramid fiber material and T700 grade carbon fiber material.

[0018] By adopting the above technical solution, the enclosure is made of para-aramid fiber material and T700 grade carbon fiber composite, which makes its specific strength about 10 times that of aluminum alloy and its specific stiffness more than 5 times that of aluminum alloy, significantly improving the structural strength and impact resistance of the enclosure. At the same time, the aramid fiber layer has excellent puncture resistance and tear resistance, which can disperse energy and protect the internal battery cells from structural deformation impacts during drops, achieving a balance between lightweight and high protection.

[0019] In one embodiment, the battery pack further includes a non-Newtonian fluid buffer layer that fills the space between the housing and the battery cell, and between the battery cells.

[0020] By employing the above technical solution, a non-Newtonian fluid buffer layer is filled between the battery cell and the casing, as well as between adjacent battery cells. This buffer layer remains soft when static, but its molecular structure instantly locks into a rigid state upon impact, allowing it to absorb and diffuse the impact force instantly. After the impact, it can return to its soft state. This dynamic response characteristic enables the battery pack to efficiently absorb energy and buffer under conditions of aircraft crashes or severe vibrations, thus improving the overall impact resistance and safety level.

[0021] In one embodiment, the non-Newtonian fluid buffer layer is made of polydiol and / or polytriol materials.

[0022] By adopting the above technical solution, the non-Newtonian fluid buffer layer made of polydiol or polyterol has an energy absorption capacity that is about 6 times higher than that of traditional EVA or polyurethane foam, and a response speed that is 7 times higher at high strain rates. It can achieve efficient energy absorption and dispersion when the aircraft falls at high speed or makes an emergency landing, greatly improving the impact resistance and airworthiness safety of the battery pack.

[0023] In one embodiment, the housing has a through hole for the lead wire of the battery cell to pass through, a reinforcing ring is provided on the housing around the through hole, and multiple reinforcing ribs are provided on the housing around the reinforcing ring in a reflective manner.

[0024] By adopting the above technical solution, a reinforcing ring and a reflective reinforcing rib structure are set around the perforation of the enclosure. This effectively disperses stress concentration in the area where the battery lead wires pass through, preventing crack propagation at the perforation site during drops or vibrations. The radial reinforcing ribs can also guide impact energy to diffuse towards the outer edge of the enclosure, enhancing the fatigue resistance of critical connection areas and the overall structural integrity.

[0025] In one embodiment, the corner areas of the housing have a reinforcing structure, which is a three-dimensional honeycomb topology.

[0026] By adopting the above technical solution, a three-dimensional honeycomb topology reinforcement structure is set in the corner area of ​​the enclosure, which can significantly improve the bending, shearing and compressive strength of the area. This three-dimensional honeycomb topology structure can form multi-path energy dissipation channels during drop or lateral impact, making the stress distribution more uniform, preventing local deformation or instability of the enclosure, and providing multi-directional protection for the battery cell.

[0027] In one embodiment, the reinforcing structure includes a first wall, a second wall, and reinforcing columns. A plurality of reinforcing columns are provided between the first wall and the second wall. The first end of each reinforcing column is connected to the first wall, and the second end is connected to the second wall. The reinforcing columns are hollow, and the plurality of reinforcing columns are sequentially combined adjacently to form a honeycomb structure.

[0028] By adopting the above technical solution, a honeycomb structure is formed by setting multiple hollow reinforcing columns between the first and second walls. The reinforcing columns can undergo controlled deformation to absorb energy when subjected to force, enabling the enclosure to achieve high energy absorption with a relatively small structural weight when subjected to impact. The cavity design further reduces mass and increases specific strength, meeting the structural requirements of eVTOL aircraft for both lightweight and impact resistance.

[0029] In one embodiment, the cross-sectional shape of the reinforcing column is a regular hexagon, and the length of one side of the regular hexagon ranges from 2 mm to 6 mm, and the wall thickness of the reinforcing column ranges from 0.1 mm to 0.5 mm.

[0030] By adopting the above technical solution, the reinforcing column uses a regular hexagonal cross-section with a side length limited to 2mm to 6mm and a wall thickness limited to 0.1mm to 0.5mm, thus achieving optimal in-plane compressive and bending resistance while maintaining lightweight design. This microscale honeycomb unit design gives the overall enclosure quasi-isotropic mechanical properties, further enhancing its resistance to drop impacts.

[0031] Secondly, this application also provides an electrical device including the battery pack described in the first aspect.

[0032] The beneficial effects of the embodiments of this application are as follows: 1. By injecting a first adhesive layer and a second adhesive layer with different elastic moduli into the tab connection area, a synergistic structure of flexible buffering and rigid support is formed. The first adhesive layer is a flexible adhesive with a low elastic modulus, covering the connection area between the electrode and the tab. It can undergo moderate deformation during the cell cycle along with the volume expansion of the electrode to absorb stress fluctuations in the connection area and reduce the risk of fatigue fracture at the connection point between the tab and the electrode. The second adhesive layer is a high-strength adhesive with a high elastic modulus, covering the connection area between the busbar and the tab. It can provide structural constraints and support under drop, vibration, and impact loads, preventing the busbar and the tab from bending or breaking under transient loads. Through the gradient arrangement of the elastic moduli of the first and second adhesive layers, the tab area can obtain appropriate buffering and reliable support under both cyclic deformation and external impact conditions, thereby improving the structural durability and safety reliability of the battery module to a certain extent. 2. The housing is made of para-aramid fiber and T700 grade carbon fiber composite material, possessing high specific strength and high specific stiffness. Combined with a non-Newtonian fluid buffer layer distributed between the cells and between the housing and the cells, the molecular structure in the buffer layer instantly locks into a rigid body to absorb impact energy upon drop or external impact. After the impact, it returns to a flexible state, thereby reducing energy concentration to a certain extent. The three-dimensional honeycomb topology reinforcement structure in the corner areas of the housing and the reflective reinforcing ribs around the perforations further disperse stress paths and avoid local structural stress concentration. Through the synergistic effect of the flexible adhesive layer, high-strength adhesive layer, non-Newtonian fluid buffer layer, and composite housing, the battery pack has excellent impact resistance and structural integrity, maintaining a stable electrical connection state in the environment of aircraft use with high drop altitude and high impact intensity, meeting high safety level airworthiness requirements. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments 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 these drawings without creative effort.

[0033] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0034] Figure 1 This is an internal cross-sectional view of the battery pack in an embodiment of this application; Figure 2 This is a partial schematic diagram of the box body at the perforation in an embodiment of this application; Figure 3 This is an exploded perspective view of the reinforcing structure in the embodiments of this application; Figure 4 This is a partial connection diagram of the reinforcing column in an embodiment of this application.

[0035] Explanation of reference numerals in the attached figures: 1. Battery cell; 11. Electrode; 12. Tab; 121. First tab; 122. Second tab; 2. Busbar; 3. First adhesive layer; 4. Second adhesive layer; 5. Top sealing section; 6. Box body; 61. Perforation; 62. Reinforcing ring; 63. Reinforcing rib; 64. Reinforcing structure; 65. First wall surface; 66. Second wall surface; 67. Reinforcing column; 7. Non-Newtonian fluid buffer layer. Detailed Implementation

[0036] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0037] Firstly, this application provides a battery pack, please refer to [link / reference]. Figure 1 The battery pack includes a cell 1, a busbar 2, a first adhesive layer 3 and a second adhesive layer 4; wherein, the cell 1 includes an electrode 11 and a tab 12, the tab 12 is connected to the electrode 11, and the busbar 2 is disposed at the end of the tab 12 away from the electrode 11.

[0038] For example, the first adhesive layer 3 is filled into the gap between the busbar 2 and the electrode 11, and the first adhesive layer 3 covers the connection between the electrode 11 and the tab 12; further, the second adhesive layer 4 is filled into the gap between the busbar 2 and the first adhesive layer 3, and the second adhesive layer 4 covers the connection between the busbar 2 and the tab 12.

[0039] For example, the elastic modulus of the first adhesive layer 3 is a, and the elastic modulus of the second adhesive layer 4 is b, where a < b.

[0040] It is understandable that the first adhesive layer 3 is more flexible than the second adhesive layer 4. That is, the flexibility of the first adhesive layer 3 is beneficial to absorbing the deformation energy of the cell 1 during the charge and discharge cycle. When the electrode 11 expands, the electrode 11 drives the tab 12 to produce a micro-displacement. The first adhesive layer 3 responds to the displacement through its own elastic extension, so that the connection between the tab 12 and the electrode 11 remains stable and not easily broken.

[0041] Meanwhile, the second adhesive layer 4 has a higher hardness and a larger elastic modulus than the first adhesive layer 3. When the battery pack is subjected to drop or vibration impact, the second adhesive layer 4 provides stable support, which helps protect the mechanical integrity of the connection interface between the busbar 2 and the tab 12. The modulus difference between the first adhesive layer 3 and the second adhesive layer 4 forms a gradient buffer region, which allows the stress to gradually decrease during transmission, thus reducing the risk of fatigue damage at the tab 12.

[0042] In some implementations, such as Figure 1 As shown, the battery pack also includes a top seal 5, with the electrode 11 located inside the top seal 5. Furthermore, the top seal 5 is hollow inside to protect the electrode 11, but the first adhesive layer 3 is also partially poured into the top seal 5 during potting.

[0043] In some embodiments, the tab 12 includes a first tab 121 and a second tab 122. The first tab 121 is embedded in the top seal 5 and connected to the electrode 11. The second tab 122 is connected to the end of the first tab 121 away from the electrode 11 and exposed in the top seal 5, and is electrically connected to the busbar 2. A first adhesive layer 3 covers the top seal 5 and the area of ​​the first tab 121, so that the connection area of ​​the battery cell 1 encapsulation end maintains a flexible interface. A second adhesive layer 4 covers the connection between the second tab 122 and the busbar 2, forming a high-strength protective band in the exposed section.

[0044] It is understandable that through this partitioned design, the internal connection area of ​​cell 1 receives flexible buffering, while the relatively outer connection area of ​​cell 1 receives rigid support, thus enabling cell 1 to have appropriate deformation space and fracture resistance under expansion and external impact conditions. The continuous transition of the adhesive layers on the inner and outer sides of the top seal 5 avoids interface peeling caused by abrupt changes in stiffness. The segmented layout of the first ear 121 and the second ear 122 also helps to accurately control the stress transmission path, making the stress on the connection area more uniform.

[0045] For example, the battery cell 1 also includes a core body, with most of the electrode 11 located inside the core body. These electrodes, through a stacked structure, constitute the main body for the electrochemical reaction of the battery cell 1. A small portion of the electrode 11 extends from the upper end of the core body, and this section is called the lead-in. The lead-in is located inside the top seal 5 and is connected to the first ear portion 121 via laser welding or ultrasonic welding, forming a conductive transition structure between the internal electrode 11 and the external busbar 2 of the battery cell 1.

[0046] In some embodiments, the first adhesive layer 3 is made of a flexible adhesive material, and the second adhesive layer 4 is made of a high-strength adhesive material. It is worth noting that in this embodiment, high-strength adhesive refers to a curable structural adhesive with high elastic modulus and high shear strength. Its tensile strength is generally not less than 20 MPa, its shear strength is not less than 15 MPa, and its elastic modulus can range from 500 MPa to 2000 MPa. This type of adhesive, after curing, has high structural support capacity and resistance to deformation, and can maintain a stable connection structure between the busbar 2 and the tab 12 region under external impact or drop loads.

[0047] For example, the first adhesive layer 3 is made of polyimide or silicone material.

[0048] For example, the second adhesive layer 4 is made of epoxy resin or polyurethane material.

[0049] It is understandable that flexible adhesive materials such as polyimide or silicone have excellent heat resistance and flexibility, maintaining a stable bonding state over a wide temperature range. They also have a high elongation at break, allowing them to stretch as the electrode 11 expands. High-strength adhesive materials such as epoxy resin or polyurethane possess high shear modulus and impact energy absorption properties, absorbing and dispersing external impact energy under transient loads. This material differentiation design establishes a functional layering system, enabling the flexible layer to perform cyclic deformation buffering and the rigid layer to perform structural protection, thereby maintaining the electrical and mechanical stability of the electrode tab 12 connection under complex working conditions.

[0050] In some embodiments, the thickness of the first adhesive layer 3 in the height direction of the cell 1 is H1, and the thickness of the second adhesive layer 4 in the height direction of the cell 1 is H2, wherein H1 < H2.

[0051] It is understandable that the thickness difference creates a gradual transition from flexible to rigid structure in the height direction of the adhesive layer, which can guide the transmission and attenuation of external forces layer by layer, reducing the peak value of local stress at the interface. The thinner first adhesive layer 3 forms a controllable flexible region on the top of the cell 1, while the thicker second adhesive layer 4 forms a high-energy absorption region on the outer layer. The synergistic distribution of the two layers is beneficial to maintaining the overall morphological stability of the adhesive layer during drop impacts or structural vibrations, while ensuring that the internal conductive connection area is not affected by excessive stretching or shearing.

[0052] In some implementations, combined with Figure 1 The battery pack also includes a housing 6, in which multiple battery cells 1 are arranged along the length of the housing 6. The first adhesive layer 3 and the second adhesive layer 4 are both filled between the multiple battery cells 1 and the inner top wall of the housing 6.

[0053] It is understood that multiple battery cells 1 of the battery pack are arranged along the length of the housing 6. A first adhesive layer 3 and a second adhesive layer 4 are encapsulated between the multiple battery cells 1 and between the battery cells 1 and the inner top wall of the housing 6, forming an integrated encapsulation system. After curing, the encapsulating material covers the upper surface of each battery cell 1 and the tab 12 area, forming a continuous elastic support network within the housing 6. This network can achieve a coordinated response of local deformation and stress diffusion under external force, possessing the dual functions of a buffer layer and structural adhesive, which is beneficial to improving the overall seismic performance and thermal cycling stability of the module. When the battery cell 1 array is subjected to a longitudinal drop impact, the first adhesive layer 3 first absorbs the initial impact energy, and the second adhesive layer 4 then further disperses the residual stress through its high-strength structure, thereby reducing the mechanical strain level of individual battery cells 1.

[0054] In some embodiments, the housing 6 is made of a composite of para-aramid fiber and T700 grade carbon fiber. The para-aramid fiber layer possesses high specific strength and excellent impact resistance, forming a tough protective zone under external impact to prevent crack propagation; the T700 grade carbon fiber layer provides high flexural stiffness, allowing the housing 6 to maintain its overall structural shape. The composite structure is significantly lighter than the traditional metal housing 6 and maintains good deformation recovery performance in multiple drop or vibration tests. The carbon fiber layer and the aramid layer are bonded together with high-temperature cured resin to form a layered stress system, which is beneficial for stress diffusion along the interlayer surface under external force, thereby reducing concentrated impact on the battery cell 1. The design of the composite housing 6 meets the dual requirements of lightweight and high strength for eVTOL aircraft.

[0055] In some implementations, combined with Figure 1 A non-Newtonian fluid buffer layer 7 is installed between the housing 6 and the battery cell 1, as well as in the gaps between adjacent battery cells 1. This buffer layer fills the structural voids and remains flexible under normal conditions. When subjected to high-speed impact or acceleration, the molecular chain structure of the non-Newtonian fluid instantaneously aligns and locks, forming a temporary rigid state to absorb and disperse impact energy. After the impact, the molecular chains return to a disordered state, allowing the buffer layer to regain its flexibility. The strain response rate of the non-Newtonian fluid is several orders of magnitude higher than that of traditional EVA or polyurethane foam, maintaining effective energy absorption performance even under high impact rates. The introduction of this buffer layer enables the battery cell 1 to achieve dynamic adaptive protection under conditions of drops, airflow disturbances, or body vibration, significantly expanding the energy absorption range.

[0056] In some embodiments, the non-Newtonian fluid buffer layer 7 is made of polydiol or polytriol. These materials contain multi-hydroxyl branched chains in their molecular structure, exhibiting excellent viscoelastic properties and a reversible shear thickening effect. When the battery pack is subjected to impacts of varying magnitudes, intermolecular hydrogen bonding produces controllable structural changes, causing the material to exhibit a low-viscosity state in the initial stage of stress to buffer low-speed impacts, and a high-viscosity state in the later stage of stress to resist high-speed impacts, thereby maintaining stable energy absorption performance over a wide velocity range. The material's energy absorption capacity is approximately six times that of traditional foam materials, and its high-speed strain response efficiency is improved by about seven times, making it suitable for the extreme drop testing requirements of eVTOL aircraft.

[0057] In some implementations, such as Figure 1 , Figure 2 As shown, the housing 6 has a through-hole 61 through which the lead wire of the power supply core 1 passes. A reinforcing ring 62 is provided around the periphery of the through-hole 61, and multiple reinforcing ribs 63 are evenly distributed around the periphery of the through-hole 61, arranged in a reflective pattern around the through-hole 61. The reinforcing ring 62 is used to strengthen the local structural rigidity of the through-hole 61 area, preventing cracks from forming in the lead wire exit area of ​​the power supply core 1 due to repeated vibration or impact. The reflective reinforcing rib design 63 helps to guide the stress concentrated in the through-hole 61 area radially to the wall surface of the housing 6, thereby dispersing the impact energy over a larger area. The geometric matching between the reinforcing ring 62 and the reinforcing ribs 63 is determined through finite element optimization, resulting in uniform stress distribution and preventing secondary concentration, which is beneficial for maintaining the sealing performance and structural integrity of the housing 6 in the long term.

[0058] In some implementations, reference is made to Figure 1 , Figure 3 and Figure 4 The corner areas of the box 6 have a reinforcing structure 64, which is a three-dimensional honeycomb topology.

[0059] For example, the reinforcing structure 64 includes a first wall surface 65, a second wall surface 66, and reinforcing columns 67. A plurality of reinforcing columns 67 are provided between the first wall surface 65 and the second wall surface 66. The first end of the reinforcing column 67 is connected to the first wall surface 65 and the second end is connected to the second wall surface 66. The reinforcing column 67 is hollow, and the plurality of reinforcing columns 67 are arranged adjacent to each other to form a honeycomb structure.

[0060] It is understood that the reinforcing columns 67 are hollow structures, and multiple reinforcing columns 67 are combined adjacently to form honeycomb-like spatial units. The geometric characteristics of the honeycomb topology enable the structure to exhibit a quasi-isotropic mechanical response under stress, which is beneficial for absorbing multi-directional impact loads. The hollow reinforcing columns 67 undergo controllable micro-buckling under external forces, generating energy dissipation, which helps reduce the transmission of instantaneous impact stress to the main body of the box 6. Through structural optimization design, the spacing between the first wall surface 65 and the second wall surface 66, the wall thickness of the reinforcing columns 67, and the arrangement density achieve a balance between mass, strength, and energy absorption performance in the honeycomb units.

[0061] In some implementations, combined with Figure 1 , Figure 3 and Figure 4 The cross-sectional shape of the reinforcing column 67 is a regular hexagon, and the length of a single side of the regular hexagon ranges from 2mm to 6mm. The wall thickness of the reinforcing column 67 ranges from 0.1mm to 0.5mm.

[0062] It is understandable that reinforced column 67 can achieve high in-plane compressive and flexural stiffness while maintaining lightweight design. The continuous arrangement of regular hexagonal structures forms a stable energy absorption path, dispersing stress in multiple directions during impact and preventing stress concentration in a single unit. Through microscale structural design, the honeycomb region exhibits predictable buckling behavior under stress, which is beneficial for maintaining stable protective performance of the battery pack during multiple impact cycles.

[0063] Secondly, this application also provides an electrical device, including the battery pack of the first aspect.

[0064] It is understood that the battery pack is installed in electrical equipment, including high-altitude operating vehicles such as aircraft or drones. The multi-level buffer system of this battery pack includes a flexible first adhesive layer 3, a rigid second adhesive layer 4, a non-Newtonian fluid buffer layer 7, and a composite material housing 6, forming an energy attenuation chain from the inside out. The flexible layer absorbs energy from micro-deformation, the rigid layer diffuses mechanical impact, the fluid layer provides dynamic response energy absorption, and the composite housing 6 provides outer protection. The entire system maintained structural integrity during a 15-meter drop test and maintained the reliability of cell 1 connections under high-frequency vibration and temperature cycling conditions, meeting the airworthiness safety requirements of aircraft. This structural design, without significantly increasing weight, is beneficial in improving the impact resistance and environmental adaptability of the battery pack, providing a stable power foundation for electric vertical takeoff and landing (EVTOL) aircraft.

[0065] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0066] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0067] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0068] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A battery pack, characterized in that, include: The battery cell (1) includes an electrode (11) and a tab (12), wherein the tab (12) is connected to the electrode (11); Busbar (2) is connected to the end of the tab (12) away from the electrode (11); A first adhesive layer (3) is filled between the busbar (2) and the electrode (11), and the first adhesive layer (3) covers the connection between the electrode (11) and the tab (12); A second adhesive layer (4) is formed between the manifold (2) and the first adhesive layer (3), and the second adhesive layer (4) covers the connection between the manifold (2) and the tab (12); wherein, The elastic modulus of the first adhesive layer (3) is a, and the elastic modulus of the second adhesive layer (4) is b, where a < b.

2. The battery pack according to claim 1, characterized in that, The battery pack further includes a top seal (5), the electrode (11) is located inside the top seal (5), and the electrode tab (12) includes a first tab (121) and a second tab (122); wherein, The first ear portion (121) is embedded in the top sealing portion (5) and connected to the electrode plate (11), and the first adhesive layer (3) covers the top sealing portion (5); The second ear (122) is connected to the end of the first ear (121) away from the electrode (11), the second ear (122) is exposed outside the top seal (5) and connected to the busbar (2), and the second adhesive layer (4) covers the second ear (122).

3. The battery pack according to claim 1, characterized in that, The first adhesive layer (3) is a flexible adhesive; and / or the second adhesive layer (4) is a high-strength adhesive.

4. The battery pack according to claim 1, characterized in that, The first adhesive layer (3) is made of polyimide or silicone; and / or the second adhesive layer (4) is made of epoxy resin or polyurethane.

5. The battery pack according to claim 1, characterized in that, The thickness of the first adhesive layer (3) in the height direction of the battery cell (1) is H1, and the thickness of the second adhesive layer (4) in the height direction of the battery cell (1) is H2, wherein H1 < H2.

6. The battery pack according to any one of claims 1 to 5, characterized in that, The battery pack also includes a housing (6), in which a plurality of battery cells (1) are arranged along the length of the housing (6), and the first adhesive layer (3) and the second adhesive layer (4) are both filled between the plurality of battery cells (1) and the inner top wall of the housing (6).

7. The battery pack according to claim 6, characterized in that, The box body (6) is made of para-aramid fiber material and T700 grade carbon fiber material.

8. The battery pack according to claim 6, characterized in that, The battery pack also includes a non-Newtonian fluid buffer layer (7), which fills the space between the housing (6) and the cell (1) and between the cells (1).

9. The battery pack according to claim 8, characterized in that, The non-Newtonian fluid buffer layer (7) is made of polydiol and / or polytriol.

10. The battery pack according to claim 6, characterized in that, The housing (6) has a through hole (61) for the lead wire of the battery cell (1) to pass through. A reinforcing ring (62) is provided on the housing (6) around the through hole (61). Multiple reinforcing ribs (63) are provided on the housing (6) around the reinforcing ring (62). The multiple reinforcing ribs (63) are arranged in a reflective manner around the through hole (61).

11. The battery pack according to claim 6, characterized in that, The corner areas of the box (6) have a reinforcing structure (64), which is a three-dimensional honeycomb topology.

12. The battery pack according to claim 11, characterized in that, The reinforcing structure (64) includes a first wall surface (65), a second wall surface (66), and reinforcing columns (67). A plurality of reinforcing columns (67) are provided between the first wall surface (65) and the second wall surface (66). The first end of the reinforcing column (67) is connected to the first wall surface (65), and the second end is connected to the second wall surface (66). The reinforcing column (67) is hollow. A plurality of reinforcing columns (67) are arranged adjacent to each other to form a honeycomb structure.

13. The battery pack according to claim 12, characterized in that, The cross-sectional shape of the reinforcing column (67) is a regular hexagon, and the length of a single side of the regular hexagon ranges from 2 mm to 6 mm. The wall thickness of the reinforcing column (67) ranges from 0.1 mm to 0.5 mm.

14. An electrical appliance, characterized in that, The battery pack includes any one of claims 1 to 13.

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