Cap assembly and cylindrical battery and electric equipment comprising same
By designing a cap assembly including explosion-proof plate, current collecting disk and ceramic washer, the safety hazards of traditional cylindrical batteries in abnormal situations is solved, and the effect of reducing the probability of fire and explosion and stabilizing the structure is achieved.
Patent Information
- Application Number
- CN202421739213.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-22
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2034-07-22
AI Technical Summary
Traditional cylindrical batteries have safety hazards under abnormal conditions such as overcharge, short circuit, and high temperature, which are prone to thermal runaway, which leads to accidents such as fire and explosion.
A cap assembly is designed, including an explosion-proof plate, a current collecting plate and a ceramic washer. The ceramic washer partially structured between the explosion-proof plate and the current collecting plate, forming a closed annular void and filling with flame retardant.
In abnormal situations, the explosion-proof plate deforms and disconnects the electrical connection, and the flame retardant flows into the battery case through the welding hole, increasing the flash point of the electrolyte, reducing the probability of fire and explosion, and stabilizing the structure through the support and insulation effect of the ceramic washer to avoid continued heat generation.
Smart Images
Figure CN222867840U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of cylindrical batteries, and specifically proposes a cap assembly and a cylindrical battery and electrical equipment comprising the cap assembly. Background Art
[0002] Traditional cylindrical batteries pose safety hazards under abnormal conditions such as overcharging, short circuit, and high temperature. They are prone to thermal runaway, which can lead to accidents such as fire and explosion, posing a threat to personal and property safety.
[0003] Although the battery protection board will provide power-off protection when the above abnormal situation occurs, considering that the battery protection board may also fail in extreme cases, it is still necessary to strengthen the safety performance of the battery structure itself. Utility Model Content
[0004] The purpose of the utility model is to solve at least part of the technical problems mentioned above, and this purpose is achieved through the following technical solutions:
[0005] In the first aspect, the utility model proposes a cap assembly, which includes an explosion-proof plate, a collecting plate and a ceramic gasket; the collecting plate has a welding hole, the explosion-proof plate is welded to the collecting plate and the welding hole is sealed; at least part of the structure of the ceramic gasket is located between the explosion-proof plate and the collecting plate, and the ceramic gasket, the explosion-proof plate and the collecting plate form a closed annular gap, and the annular gap is filled with a flame retardant.
[0006] In some embodiments, the cap assembly further comprises a top cover and a ceramic layer; the top cover is connected to a side of the bursting disk facing away from the collecting plate, and the ceramic layer is connected to a side of the top cover facing the bursting disk.
[0007] In some embodiments, the thickness of the ceramic layer is d, then 0.1 mm≤d≤0.4 mm.
[0008] In some embodiments, the cap assembly further comprises a sealing ring connected to the periphery of the top cover, the burst disk and the ceramic gasket.
[0009] In some embodiments, the ceramic gasket and the explosion-proof disk, as well as the ceramic gasket and the collecting plate are connected by high-temperature resistant sealant.
[0010] In some embodiments, the volume of the annular space is V, then 0.1 mL≤V≤0.2 mL.
[0011] In a second aspect, the utility model further provides a cylindrical battery, which comprises the cap assembly of the first aspect.
[0012] In some embodiments, the cylindrical battery further includes an upper ceramic gasket and a lower ceramic gasket spaced apart from each other; the upper ceramic gasket has a positive pole ear avoidance hole and a plurality of through holes for exhaust, and the lower ceramic gasket has a negative pole ear avoidance hole.
[0013] In some embodiments, the upper ceramic gasket and the lower ceramic gasket are both porous ceramic structures, and storage spaces are formed inside the two, respectively, and the storage spaces are filled with electrolyte.
[0014] In a third aspect, the utility model further proposes an electrical device, which includes the cylindrical battery of the second aspect.
[0015] The technical solution provided by the utility model has at least the following technical effects:
[0016] In the utility model, when the cylindrical battery is in abnormal operating conditions such as overcharge, short circuit and high temperature, the heat and gas production inside the battery cell will increase. First, the explosion-proof plate is deformed and flipped up and electrically disconnected from the current collecting plate, eliminating the subsequent heat generation of the circuit, and the welding hole is exposed in the process; secondly, the flame retardant in the annular gap flows into the shell of the cylindrical battery through the welding hole and contacts with the electrolyte, thereby increasing the flash point of the electrolyte and reducing the probability of fire and explosion of the cylindrical battery; in addition, the ceramic gasket has a supporting and insulating effect, and it is not easy to melt itself, so that the structure is stable, avoiding the explosion-proof plate and the current collecting plate from overlapping to form a passage, which leads to continued heat generation. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to better combine the contents shown in the drawings of the specification with the contents described in the specific implementation methods, the drawings of the specification are briefly introduced below. It can be understood that the drawings of the specification mentioned below only schematically show some embodiments of the relevant technical solutions and the solutions of the utility model, and those skilled in the art can also make drawings showing other embodiments without creative work.
[0018] Specifically, the annotations of the drawings in the specification are as follows:
[0019] Figure 1 This is a schematic structural diagram of the cap assembly according to an embodiment of the utility model;
[0020] Figure 2 This is a schematic diagram of the structure of the upper ceramic gasket described in an embodiment of the utility model;
[0021] Figure 3 It is a structural schematic diagram of the lower ceramic gasket described in an embodiment of the utility model.
[0022] Specifically, the annotations of the accompanying drawings in the specification are as follows:
[0023] 100, cap assembly; 110, top cover; 120, ceramic layer; 130, explosion-proof disk; 140, collecting plate; 150, sealing ring; 160, ceramic gasket; 170, flame retardant; 200, upper ceramic gasket; 210, through hole; 220, positive ear avoidance hole; 300, lower ceramic gasket; 310, negative ear avoidance hole. DETAILED DESCRIPTION
[0024] In order to make the contents of the embodiments of the utility model clearer, the following description will be made in conjunction with the drawings of the specification. It can be understood that the contents mentioned below are only part of the embodiments of the utility model, rather than all the embodiments. Based on this, other embodiments obtained without creative work are all within the scope of protection of the utility model.
[0025] It should be understood that the terms used herein are only for the purpose of describing specific embodiments and are not intended to strictly limit the technical solutions unless the context clearly indicates otherwise. For example, the use of "a", "an" and "the" to modify a feature does not exclude that the feature may also be plural in another embodiment.
[0026] It should be understood that the terms "include", "comprising", and "having" are open ended and therefore specify the presence of stated features but do not exclude the presence of other features. Similarly, although the terms first, second, etc. may be used herein to describe multiple features, these features should not be limited by these terms, which are only used to distinguish one feature from another, and unless the context clearly indicates otherwise, terms such as "first", "second", and other numerical terms do not imply a sequence or order when used herein.
[0027] It should be understood that, unless the context clearly indicates otherwise, the terms "dispose", "connect", and "install" should be understood in a broad sense, for example, they can be fixedly connected, detachably connected, or integrally connected; they can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.
[0028] In addition, for the convenience of description, terms of spatial relative relationships are used in the text to illustrate the position of one feature relative to another feature, for example, "inside", "outside", "end", "side", "upper", "middle", "lower", "high", "low", "axial", "circumferential", "radial", "horizontal", "vertical", "first direction", "second direction", etc. It can be understood that the spatial relative relationship between two features should include other embodiments in addition to those shown in the drawings of the specification.
[0029] The embodiments of the present utility model are described below in conjunction with the accompanying drawings.
[0030] First, refer to Figure 1 The utility model proposes a cap assembly 100, which includes an explosion-proof disc 130, a collecting disc 140 and a ceramic gasket 160; the collecting disc 140 has a welding hole, the explosion-proof disc 130 is welded to the collecting disc 140 and the welding hole is blocked; at least part of the structure of the ceramic gasket 160 is located between the explosion-proof disc 130 and the collecting disc 140, and the ceramic gasket 160, the explosion-proof disc 130 and the collecting disc 140 form a closed annular gap, and the annular gap is filled with a flame retardant 170.
[0031] In the utility model, when the cylindrical battery is in abnormal operating conditions such as overcharge, short circuit and high temperature, the heat and gas production inside the battery cell will increase. First, the explosion-proof plate 130 is deformed and flipped up and disconnected from the collecting plate 140, thereby eliminating the subsequent heat generation of the circuit and exposing the welding hole in the process; secondly, the flame retardant 170 in the annular gap flows into the shell of the cylindrical battery through the welding hole and contacts with the electrolyte, thereby increasing the flash point of the electrolyte and reducing the probability of fire and explosion of the cylindrical battery; in addition, the ceramic gasket 160 has a supporting and insulating effect, and it is not easy to melt itself, so that the structure is stable, avoiding the explosion-proof plate 130 and the collecting plate 140 from overlapping to form a passage, which leads to continued heat generation.
[0032] It is understandable that the cap assembly 100 proposed by the present invention can be adapted to other types of batteries besides cylindrical batteries, such as square batteries, special-shaped batteries, etc., by changing its shape. The present invention does not limit the application of the cap assembly 100.
[0033] In some embodiments, reference Figure 1 The cap assembly 100 further includes a top cover 110 and a ceramic layer 120; the top cover 110 is connected to the side of the explosion-proof disk 130 facing away from the collecting plate 140, and the ceramic layer 120 is connected to the side of the top cover 110 facing the explosion-proof disk 130. In some embodiments, the thickness of the ceramic layer 120 is d, then 0.1 mm≤d≤0.4 mm.
[0034] In the above embodiment, even if the cylindrical battery has thermal runaway and causes an explosion accident, the presence of the top cover 110 and the ceramic layer 120 will block the height and impact range of the combustion spray during thermal runaway, thereby reducing the risk of injury caused by thermal runaway; specifically, the ceramic layer 120 has a high hardness and is resistant to high temperatures, which can reduce the distance that the flame and battery component fragments are sprayed outward, thereby ensuring the safety of surrounding objects and personnel.
[0035] It should be noted that the thickness of the ceramic layer 120 should not be too thin or too thick. If it is too thin, it will affect the protection effect, and if it is too thick, it will affect the size of the cylindrical battery. Specifically, the thickness of the ceramic layer 120 can be, but is not limited to, 0.1 mm, 0.2 mm, or 0.4 mm.
[0036] In some embodiments, reference Figure 1 The cap assembly 100 further includes a sealing ring 150, which is connected to the periphery of the top cover 110, the explosion-proof disk 130 and the ceramic gasket 160. In some embodiments, the ceramic gasket 160 and the explosion-proof disk 130, as well as the ceramic gasket 160 and the collecting plate 140 are connected by high temperature resistant sealant. In some embodiments, the volume of the annular gap is V, then 0.1 mL≤V≤0.2 mL.
[0037] In the above embodiment, the cap assembly 100 seals the opening of the battery housing with the sealing ring 150 to prevent dust and leakage. In addition, in order to prevent the flame retardant 170 from leaking into the cylindrical battery during normal use, affecting the normal reaction of the electrolyte, and also causing insufficient residual amount of the flame retardant 170 under abnormal conditions, a special high-temperature resistant sealant is used to seal the joints between the ceramic gasket 160, the explosion-proof disc 130 and the collecting plate 140, so that the flame retardant 170 can only flow into the battery housing and contact the electrolyte according to the planned timing and path, which is easy to control. Furthermore, the space of the annular gap surrounded by the ceramic gasket 160, the explosion-proof disc 130 and the collecting plate 140 cannot be too large or too small. If the annular gap is too large, it will affect the battery size. If it is too small, the amount of the flame retardant 170 installed will be too small, affecting the flame retardant effect; specifically, the volume of the annular gap can be, but is not limited to, 0.1mL, 0.15mL, and 0.2mL.
[0038] In some embodiments, the flame retardant 170 can be any one of TMP (trimethyl phosphate), TEP (triethyl phosphate), DMMP (dimethyl phosphite), DMMEMP (dimethoxymethyl ethyl phosphate), TPP (triphenyl phosphate), CDP (chlorodiphenyl phosphate), DPOF (diphenyl phosphine oxide), TMPP (trimethoxypropyl phosphate), RDP (isopropyl phenyl phosphate), MFE (trifluoroethyl phosphate), FEMC (2,2,2-trifluoroethyl phosphite), DFDEC (difluoroethyl diethyl phosphate), HFPM (hexafluoropropyl methyl phosphate), F-EPE (trifluoroethoxy phosphite), TEEP (tetraethyl acyl phosphate), TTFP (tris (trifluoromethyl) phenyl phosphate), PFPN (polyfluorophenyl phosphite), FPPN (polyfluorophenyl phosphate) and HEPN (diethyl phosphate nitrogen heterocyclic oxide) or a combination of any two or more thereof.
[0039] In a second aspect, the present invention further provides a cylindrical battery, which includes the cap assembly 100 of the first aspect. In some embodiments, referring to Figure 2 and Figure 3The cylindrical battery further includes an upper ceramic gasket 200 and a lower ceramic gasket 300 spaced apart from each other; the upper ceramic gasket 200 has a positive tab avoidance hole 220 and a plurality of through holes 210 for exhaust, and the lower ceramic gasket 300 has a negative tab avoidance hole 310. The positive tab avoidance hole 220 and the negative tab avoidance hole 310 are used to penetrate the positive tab and the negative tab, respectively.
[0040] In the above embodiment, when the cylindrical battery causes thermal runaway due to overcharging, short circuit or overheating, resulting in fire and explosion, the upper ceramic gasket 200 and the lower ceramic gasket 300 will work together with the top cover 110 and the ceramic layer 120 thereon to provide a certain barrier effect. The ceramic material is not easily melted by the high-temperature flame, thereby reducing the height and impact range of the combustion spray, reducing the distance that the flame and battery component fragments are ejected outward, and reducing the risk of injury to the surrounding environment and personnel. In addition, the upper ceramic gasket 200 is distributed with a large number of through holes 210 to prevent the internal gas of the battery from being unable to be released and causing an explosion; specifically, a large amount of gas generated inside the cylindrical battery will flow from the through holes 210 of the upper ceramic gasket 200 to the explosion-proof plate 130 and break through the valve port of the explosion-proof plate 130 to be discharged.
[0041] In some embodiments, the upper ceramic gasket 200 and the lower ceramic gasket 300 are both porous ceramic structures, and storage spaces are formed inside the two, respectively, and the storage spaces are filled with electrolyte.
[0042] In this embodiment, the porous ceramic structure of the upper ceramic gasket 200 and the lower ceramic gasket 300 provides storage space for the electrolyte. When the cylindrical battery circulates for a long time and the electrolyte is consumed, the electrolyte filled in the storage space can replenish it, thereby improving the cycle performance of the cylindrical battery.
[0043] In a third aspect, the utility model further proposes an electrical device, which includes the cylindrical battery of the second aspect.
[0044] Specifically, the cylindrical battery of the second aspect and the electrical equipment of the third aspect both include the cap assembly 100 of the first aspect, so the cylindrical battery of the second aspect and the electrical equipment of the third aspect have at least all the technical effects of the cap assembly 100 of the first aspect, and the technical effects of the cap assembly 100 are no longer repeated here.
[0045] It can be understood that the embodiments of the present invention only propose structures of cylindrical batteries and electrical equipment related to the improvements of the present invention, but it does not mean that the cylindrical batteries and electrical equipment in the present invention do not have other structures. For example, the cylindrical battery also includes a shell, the electrical equipment also includes a battery protection plate, etc. Other structures will not be elaborated one by one here.
[0046] In particular, the term "and / or" in the present invention should be understood as follows:
[0047] In the first case, the term "and / or" located between a first subject and a second subject includes any one of the following meanings: (1) only the first subject; (2) only the second subject; and (3) the first subject and the second subject.
[0048] In the second case, the term "and / or" between the last two subjects among three or more subjects means including at least any one of the multiple subjects. For example, "the first subject, the second subject and / or the third subject" has the same meaning as "the first subject and / or the second subject and / or the third subject", specifically including the following combinations: (1) only the first subject; (2) only the second subject; (3) only the third subject; (4) the first subject and the second subject but not the third subject; (5) the first subject and the third subject but not the second subject; (6) the second subject and the third subject but not the first subject; and (7) the first subject, the second subject and the third subject.
[0049] In addition, although the above content describes the embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art can also make various modifications and variations without departing from the concept of the present invention, and such modifications and variations will fall within the scope of protection of the present invention.
Claims
1. A cap assembly, characterized in that: It comprises an explosion-proof disk (130), a collecting plate (140) and a ceramic gasket (160); The current collecting plate (140) has a welding hole, and the explosion-proof plate (130) is welded to the current collecting plate (140) to seal the welding hole; At least part of the structure of the ceramic gasket (160) is located between the explosion-proof disk (130) and the current collecting disk (140); the ceramic gasket (160), the explosion-proof disk (130) and the current collecting disk (140) form a closed annular space, and the annular space is filled with a flame retardant (170).
2. The cap assembly according to claim 1, characterized in that: The cap assembly (100) further comprises a top cover (110) and a ceramic layer (120); The top cover (110) is connected to a side of the explosion-proof disk (130) facing away from the current collecting plate (140), and the ceramic layer (120) is connected to a side of the top cover (110) facing the explosion-proof disk (130).
3. The cap assembly according to claim 2, characterized in that: The thickness of the ceramic layer (120) is d, then 0.1 mm≤d≤0.4 mm.
4. The cap assembly according to claim 2, characterized in that: The cap assembly (100) further comprises a sealing ring (150), wherein the sealing ring (150) is connected to the periphery of the top cover (110), the explosion-proof disk (130) and the ceramic gasket (160).
5. The cap assembly according to claim 1, characterized in that: The ceramic gasket (160) and the explosion-proof disk (130), as well as the ceramic gasket (160) and the current collecting plate (140) are both connected via high-temperature resistant sealant.
6. The cap assembly according to any one of claims 1 to 5, characterized in that: The volume of the annular space is V, then 0.1 mL≤V≤0.2 mL.
7. A cylindrical battery, characterized in that: A cap assembly (100) comprising any one of claims 1 to 6.
8. The cylindrical battery according to claim 7, characterized in that: The cylindrical battery further comprises an upper ceramic gasket (200) and a lower ceramic gasket (300) which are spaced apart from each other. The upper ceramic gasket (200) has a positive electrode tab avoidance hole (220) and a plurality of through holes (210) for exhaust, and the lower ceramic gasket (300) has a negative electrode tab avoidance hole (310).
9. The cylindrical battery according to claim 8, characterized in that: The upper ceramic gasket (200) and the lower ceramic gasket (300) are both porous ceramic structures, and storage spaces are formed inside the two, respectively, and the storage spaces are filled with electrolyte.
10. An electrical device, characterized in that: A cylindrical battery comprising any one of claims 7 to 9.