Battery, battery pack, and electric device

Abstract

The application relates to the technical field of batteries, and particularly discloses a battery, a battery pack and a power utilization device, wherein the battery comprises a shell, a battery cell, a cover plate and a patch. The shell is provided with an opening, the battery cell is arranged in the shell, and the cover plate covers and seals the opening; the patch comprises a reinforcing layer and a supporting layer, the reinforcing layer is embedded in the inside of the supporting layer, and the supporting layer is arranged on the side of the cover plate away from the battery cell. In the application, the reinforcing layer and the supporting layer form a multilayer protective barrier in a composite manner, wherein the reinforcing layer can block the contact between the high-temperature eruption generated by other batteries and the cover plate in the battery, and can effectively block the spread of thermal runaway; in addition, the supporting layer wraps the reinforcing layer, can provide mechanical strength and structural stability, and prevents the whole patch from deforming or peeling off under high temperature.

Description

Technical Field

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

[0002] Currently, battery packs are generally integrated from multiple compactly arranged individual cells through series and parallel connections to achieve high energy density and lightweight design.

[0003] During battery pack operation, if a single cell experiences thermal runaway due to internal short circuits, mechanical damage, or other reasons, its internal temperature can rapidly rise to hundreds or even thousands of degrees Celsius, ejecting high-temperature substances that can affect adjacent cells. Specifically, under these extreme high-temperature conditions, the insulating patches on the outer side of adjacent battery covers can melt rapidly, causing the covers to come into direct contact with the ejected high-temperature substances. These substances may cause localized softening and deformation of the covers, or even melt through them, potentially triggering the spread of thermal runaway. Utility Model Content

[0004] The purpose of this application is to solve at least some of the technical problems mentioned above, and this purpose is achieved through the following technical solutions: In a first aspect, this application provides a battery comprising a casing, a battery cell, a cover plate, and a patch. The casing has an opening, the battery cell is disposed inside the casing, and the cover plate seals the opening; the patch includes a reinforcing layer and a supporting layer, the reinforcing layer being embedded inside the supporting layer, and the supporting layer being disposed on the side of the cover plate facing away from the battery cell.

[0005] Secondly, this application proposes a battery pack including a busbar and a plurality of batteries according to the first aspect. The batteries include terminals, one end of which is electrically connected to a cell and the other end of which is electrically connected to the busbar. There is an electrical gap between the patch and the busbar, and the electrical gap is filled with insulating colloid.

[0006] Thirdly, this application proposes an electrical device that includes either the battery pack of the second aspect or the battery of the first aspect.

[0007] The technical solution proposed in this application has at least the following technical effects: In this application, the reinforcing layer and the support layer are combined to form a multi-layer protective barrier. The reinforcing layer can block the contact between the high-temperature ejecta generated by other batteries and the cover plate in this battery, which can effectively block the spread of thermal runaway. In addition, the support layer wraps the reinforcing layer, which can provide mechanical strength and structural stability, and prevent the patch from deforming or peeling off at high temperatures. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0009] Figure 1 This is a schematic diagram of the battery structure described in an embodiment of this application; Figure 2 This is a schematic diagram of the battery cell structure described in the embodiments of this application; Figure 3 This is a partial cross-sectional schematic diagram of the cover plate described in an embodiment of this application; Figure 4 This is a partial cross-sectional schematic diagram of the patch described in an embodiment of this application.

[0010] Explanation of reference numerals in the attached figures: 10. Housing; 20. Battery cell; 30. Cover plate; 301. Explosion-proof valve; 302. Flanged edge; 40. Patch; 401. Reinforcing layer; 402. Supporting layer; 403. Adhesive layer; 50. Terminal post; 60. Busbar; 70. Insulating colloid. Detailed Implementation

[0011] 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 and completely 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.

[0012] The embodiments of this application are described below with reference to the accompanying drawings. It can be understood that the technical features involved in the different embodiments described below can be combined with each other as long as they do not conflict with each other.

[0013] Firstly, combining Figures 1 to 4 Key reference Figure 3 and Figure 4 The present application provides an embodiment of a battery, which includes a housing 10, a battery cell 20, a cover plate 30, and a patch 40. The housing 10 has an opening, the battery cell 20 is disposed inside the housing 10, and the cover plate 30 covers the opening; the patch 40 includes a reinforcing layer 401 and a supporting layer 402, the reinforcing layer 401 is embedded inside the supporting layer 402, and the supporting layer 402 is disposed on the side of the cover plate 30 facing away from the battery cell 20.

[0014] In this embodiment, the reinforcing layer 401 and the supporting layer 402 form a multi-layer protective barrier through a composite method. The reinforcing layer 401 can block the contact between the high-temperature ejected material generated by other batteries and the cover plate 30 in this battery, which can effectively block the spread of thermal runaway. In addition, the supporting layer 402 wraps around the reinforcing layer 401, which can provide mechanical strength and structural stability, prevent the patch 40 from deforming or peeling off at high temperatures, and maintain the insulation function at high temperatures.

[0015] In some embodiments, refer to Figure 3 The thickness of the reinforcing layer 401 is d1mm, and the thickness of the supporting layer 402 is d2mm, and both satisfy 5%≤d1 / d2≤70%.

[0016] In this embodiment, by optimizing the thickness ratio of the reinforcing layer 401 and the supporting layer 402, the thermal insulation performance and mechanical strength are balanced. The reinforcing layer 401 can enhance the thermal insulation performance, and the supporting layer 402 can enhance the compressive strength, thus preventing the patch 40 from collapsing as a whole.

[0017] Specifically, d1 / d2 can take any one of the following values: 5%, 10%, 20%, 30%, 40%, 50%, 60%, and 70%, or a range between any two of these values.

[0018] Specifically, the reinforcing layer 401 is disposed inside the support layer 402 to improve adhesion to the surface of the patch 40 and prevent chemicals from corroding the fibers of the reinforcing layer 401.

[0019] In some embodiments, refer to Figure 3 The thickness d1mm of the reinforcing layer 401 satisfies 0.02mm≤d1mm≤1mm, and / or the thickness d2mm of the support layer 402 satisfies 0.1mm≤d2mm≤2mm.

[0020] In this embodiment, the thickness of the reinforcing layer 401 and the supporting layer should be moderate to balance their functional effects with space occupation, and to avoid affecting the assembly of other components.

[0021] Specifically, d1mm can take any one of the following values ​​or a range between any two of them: 0.02mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, and 1mm; d2mm can take any one of the following values ​​or a range between any two of them: 0.1mm, 0.5mm, 1mm, 1.5mm, and 2mm.

[0022] In some embodiments, refer to Figure 4 The support layer 402 wraps around the end of the reinforcing layer 401.

[0023] In this embodiment, the support layer 402 wraps around the end of the reinforcing layer 401 to prevent the end of the reinforcing layer 401 from protruding and stabbing the assembly personnel or scratching other parts.

[0024] In some embodiments, refer to Figure 4 The end of the reinforcing layer 401 and the end of the supporting layer 402 are spaced d3mm apart, and the condition 0.1mm≤d3mm≤5mm is met.

[0025] In this embodiment, optimizing the spacing between the end of the reinforcing layer 401 and the end of the support layer 402 ensures that the support layer 402 completely covers the end of the reinforcing layer 401, and also ensures the coverage area of ​​the reinforcing layer 401.

[0026] Specifically, d3mm can take any one of the following values: 0.1mm, 0.5mm, 1mm, 2mm, 3mm, 4mm, and 5mm, or a range between any two of these values.

[0027] In some embodiments, the melting point of the reinforcing layer 401 is between 150°C and 2050°C.

[0028] In this embodiment, the melting point of the reinforcing layer 401 is higher than the temperature of battery thermal runaway, ensuring that the structure remains intact at high temperatures.

[0029] In particular, in thermogravimetric analysis (TGA), the material of reinforcing layer 401 satisfies the 5% mass loss temperature (T5%) > 200℃, which means that the material has good thermal stability in high-temperature environments and its decomposition or melting initiation temperature is relatively high.

[0030] In some embodiments, the reinforcing layer 401 comprises one or more of glass fiber structure, carbon fiber, polymer fiber or inorganic fiber, and / or the supporting layer 402 comprises a resin structure.

[0031] Among them, the melting point of inorganic fibers can reach 1800℃; in addition, the resin structure mentioned above can be polypropylene resin, epoxy resin, polycarbonate resin, polyurethane resin or phenolic resin, which have no melting point and are usually carbonized at high temperature.

[0032] In some embodiments, the reinforcing layer 401 has a plurality of mesh openings, and the support layer 402 fills the mesh openings.

[0033] In this embodiment, the mesh of the reinforcing layer 401 can not only ensure structural strength, but also enhance overall thermal conductivity, and at the same time make the reinforcing layer 401 and the support layer 402 more firmly bonded.

[0034] In some embodiments, the length of the mesh is 0.01 mm to 5 mm, and it is understood that when the mesh is a circular hole, the diameter of the circular hole is 0.01 mm to 5 mm.

[0035] In some embodiments, refer to Figure 4 The patch 40 also includes an adhesive layer 403, which is adhered between the support layer 402 and the cover plate 30. The thickness of the adhesive layer 403 is d4mm, and satisfies 0.01mm≤d4mm≤0.2mm.

[0036] In this embodiment, the patch 40 is bonded to the cover plate 30 using an adhesive layer 403, resulting in good adhesion and convenient operation. The thickness of the adhesive layer 403 is moderate to balance the bonding strength and space occupation.

[0037] Specifically, d4mm can take any one of the following values: 0.01mm, 0.05mm, 0.1mm, 0.15mm, and 0.2mm, or a range between any two of these values.

[0038] In some embodiments, the roughness of the support layer 402 is 0.05mm ≤ Rzmm ≤ 1mm. Specifically, Rzmm can take any one of 0.05mm, 0.08mm, 0.1mm, 0.4mm, 0.6mm, 0.8mm and 1mm or a range between any two of these values.

[0039] In this embodiment, the roughness of the support layer 402 is optimized to enhance the bonding strength between the adhesive layer 403 and it, thereby improving adhesion.

[0040] In some embodiments, refer to Figure 1 and Figure 2 The cover plate 30 is equipped with an explosion-proof valve 301, and the patch 40 is provided with grooves that correspond to the explosion-proof valve 301.

[0041] In this embodiment, the grooves on the patch 40 are aligned with the position of the explosion-proof valve 301, which can directionally release pressure in the event of thermal runaway, avoid affecting the performance of the explosion-proof valve 301, and prevent the risk of explosion by releasing the gas inside the battery.

[0042] In some embodiments, refer to Figures 1 to 3 Key reference Figure 3 The battery also includes a terminal post 50, one end of which is provided with a cover plate 30 and electrically connected to the cell 20. The cover plate 30 has a flange 302 and wraps around the terminal post 50. The patch 40 covers at least part of the flange 302.

[0043] In this embodiment, the patch 40 covers the flange 302 at the pole post 50, increasing the protection range and improving structural reliability.

[0044] In some embodiments, refer to Figure 3 The patch 40 completely covers the flange 302.

[0045] In some embodiments, refer to Figure 3The edges of the flange 302 and the patch 40 are staggered, with a staggered spacing of <0.5mm.

[0046] In this embodiment, the edges of the flange 302 and the patch 40 are staggered to ensure complete coverage of the flange 302. The high-voltage connection structure at the pole 50 is a critical path for thermal runaway propagation and must be blocked by insulation protection.

[0047] Secondly, referring to Figure 3 The embodiments of this application propose a battery pack including a busbar 60 and a plurality of batteries of the first aspect. The batteries include terminals 50, one end of which is electrically connected to a cell 20 and the other end of which is electrically connected to the busbar 60. There is an electrical gap between the patch 40 and the busbar 60, and the electrical gap is filled with insulating colloid 70.

[0048] In this embodiment, the insulating colloid 70 between the busbar 60 and the patch 40 is filled to further block arc discharge, prevent cross-battery short circuit from causing cascading thermal runaway, and meet the creepage distance requirements.

[0049] It should be noted that the busbar 60 is connected between the terminals 50 of two adjacent batteries.

[0050] Thirdly, embodiments of this application propose an electrical device that includes a battery pack of the second aspect or a battery of the first aspect.

[0051] Understandably, the battery pack of the second aspect and the power device of the third aspect both have all the technical effects of the battery of the first aspect, and their specific technical effects will not be elaborated here.

[0052] It should be noted that the battery pack in the second aspect and the electrical device in the third aspect also include other components, which will not be described in detail here.

[0053] In particular, the term "and / or" in this application should be understood as follows: In the first case, the term “and / or” between the first subject and the second subject includes any of the following meanings: (1) only the first subject; (2) only the second subject; and (3) both the first subject and the second subject.

[0054] In the second case, the term "and / or" between the last two of three or more subjects means including at least one of the subjects. For example, "first subject, second subject and / or third subject" has the same meaning as "first subject and / or second subject and / or third subject", specifically including the following combinations: (1) only the first subject; (2) only the second subject; (3) only the third subject; (4) first subject and second subject and no third subject; (5) first subject and third subject and no second subject; (6) second subject and third subject and no first subject; and (7) first subject, second subject and third subject; Furthermore, the character " / " in this application indicates that the objects before and after it are in an "or" relationship.

[0055] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by this application.

Claims

1. A battery, characterized in that, include: The housing (10) has an opening; The battery cell (20) is disposed inside the housing (10); Cover plate (30) to seal the opening; The patch (40) includes a reinforcing layer (401) and a supporting layer (402), wherein the reinforcing layer (401) is embedded inside the supporting layer (402), and the supporting layer (402) is disposed on the side of the cover plate (30) facing away from the cell (20).

2. The battery according to claim 1, characterized in that, The thickness of the reinforcing layer (401) is d1mm, and the thickness of the supporting layer (402) is d2mm, and both satisfy 5%≤d1 / d2≤70%.

3. The battery according to claim 2, characterized in that, The thickness d1mm of the reinforcing layer (401) satisfies 0.02mm≤d1mm≤1mm, and / or the thickness d2mm of the supporting layer (402) satisfies 0.1mm≤d2mm≤2mm.

4. The battery according to claim 1, characterized in that, The support layer (402) wraps around the end of the reinforcing layer (401).

5. The battery according to claim 4, characterized in that, The end of the reinforcing layer (401) and the end of the supporting layer (402) are spaced d3mm apart, and the condition 0.1mm≤d3mm≤5mm is satisfied.

6. The battery according to claim 1, characterized in that, The melting point of the reinforcing layer (401) is 150°C to 2050°C.

7. The battery according to claim 1, characterized in that, The reinforcing layer (401) comprises one or more of glass fiber structure, carbon fiber, polymer fiber or inorganic fiber, and / or the supporting layer (402) comprises resin structure.

8. The battery according to claim 1, characterized in that, The reinforcing layer (401) has a plurality of mesh openings, and the supporting layer (402) fills the mesh openings.

9. The battery according to claim 8, characterized in that, The length of the mesh is from 0.01 mm to 5 mm.

10. The battery according to claim 1, characterized in that, The patch (40) also includes an adhesive layer (403), which is adhered between the support layer (402) and the cover plate (30). The thickness of the adhesive layer (403) is d4mm, and satisfies 0.01mm≤d4mm≤0.2mm.

11. The battery according to claim 1, characterized in that, The roughness of the support layer (402) is 0.05mm≤Rzmm≤1mm.

12. The battery according to any one of claims 1 to 11, characterized in that, The cover plate (30) is provided with an explosion-proof valve (301), and the patch (40) is provided with grooves, which correspond to the explosion-proof valve (301).

13. The battery according to any one of claims 1 to 11, characterized in that, The battery also includes a terminal post (50), one end of which passes through the cover plate (30) and is electrically connected to the cell (20). The cover plate (30) has a flange (302) and wraps around the terminal post (50). The patch (40) covers at least part of the flange (302).

14. The battery according to claim 13, characterized in that, The patch (40) completely covers the flange (302).

15. The battery according to claim 13, characterized in that, The edge of the flange (302) and the edge of the patch (40) are staggered, and the staggered distance is <0.5mm.

16. A battery pack, characterized in that, The battery includes a busbar (60) and a plurality of batteries according to any one of claims 1 to 15, the battery including a terminal (50), one end of the terminal (50) being electrically connected to the cell (20), the other end of the terminal (50) being electrically connected to the busbar (60), an electrical gap being provided between the patch (40) and the busbar (60), the electrical gap being filled with an insulating colloid (70).

17. An electrical device, characterized in that, Includes the battery pack as described in claim 16 or the battery as described in any one of claims 1 to 15.

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