Temperature explosion-proof cover plate and lithium ion battery with same
By using a thermal component and connection layer in the battery design, slow pressure release at high temperatures is achieved, which solves the risk of battery explosion and improves safety and service life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHANGZHOU MICROBAT TECH CO LTD
- Filing Date
- 2025-05-06
- Publication Date
- 2026-05-15
AI Technical Summary
Existing batteries pose an explosion risk at high temperatures. While existing pressure relief valve structures can release pressure, the release method is violent and may cause secondary disasters.
The design employs a thermally sensitive component (such as PTC) combined with a connecting layer. The battery temperature is controlled by voltage division and current limiting. The connecting layer melts at high temperatures to form a pressure relief port, slowly releasing pressure and preventing explosion.
It effectively controls battery temperature, alleviates pressure release, prevents explosions, improves safety, reduces the risk of secondary disasters, and the thermal component can be used multiple times at a low cost.
Smart Images
Figure CN224248758U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of battery structure technology, specifically relating to battery cover plates, and more particularly to a temperature-resistant explosion-proof cover plate and a lithium-ion battery having the same. Background Technology
[0002] In modern daily life, batteries, as indispensable energy carriers, are deeply integrated into various electronic products and household appliances, providing great convenience to people's lives. Whether it's smartphones, smartwatches, wireless headphones, or power tools, batteries play a central role. However, when batteries are subjected to improper operation such as overcharging, short circuits, or high temperatures, the internal electrochemical reactions accelerate dramatically, causing the battery temperature to rise rapidly in a short period. As the temperature continues to rise, the decomposition of the active materials inside the battery intensifies, a large amount of gas accumulates, and the pressure increases sharply. Once the internal pressure exceeds the battery casing's tolerance limit, it may trigger a violent explosion, causing not only serious damage to the device but also endangering the user's personal safety.
[0003] To effectively address this safety hazard, current battery designs commonly employ pressure relief valves. When the internal pressure of the battery reaches a preset threshold, high-pressure gas ruptures the valve, releasing the internal pressure and preventing explosions due to excessive pressure. However, this pressure relief method does not completely eliminate the safety hazard. Because the pressure release is quite intense, it still possesses a certain degree of explosiveness, potentially accompanied by high-temperature gas ejection and battery fragmentation. Under certain conditions, it still poses a possibility of secondary disasters. To further improve safety performance, a temperature-resistant explosion-proof cover and a lithium-ion battery incorporating it are proposed to address this issue. Utility Model Content
[0004] This utility model aims to solve at least one of the technical problems existing in the prior art.
[0005] Therefore, this utility model proposes a temperature-resistant explosion-proof cover and a lithium-ion battery having the same, which has the advantage of providing pressure relief and explosion protection at high temperatures.
[0006] The temperature-resistant explosion-proof cover plate and the lithium-ion battery having the same according to an embodiment of the present invention include: a first connecting piece, a second connecting piece, a connecting layer, and a thermal component; the first connecting piece and the second connecting piece are respectively used to connect the positive and negative electrodes of the battery; the thermal component is disposed at one end of the first connecting piece and is electrically connected to the first connecting piece; the first connecting piece has a first through hole formed along its thickness direction, and the thermal component has a second through hole formed along its thickness direction, the projection surface of the second through hole completely covering the first through hole; the second connecting piece is located inside the second through hole and covers the first through hole; the connecting layer is used to connect the first connecting piece and the second connecting piece, and the connecting layer is a hot-melt material.
[0007] According to one embodiment of the present invention, the other end of the first connecting piece is sealed to the battery casing.
[0008] According to one embodiment of the present invention, the thermal component is a PTC.
[0009] According to one embodiment of the present invention, the size of the second through hole is larger than the size of the second connecting piece, so as to avoid contact with the second connecting piece.
[0010] According to one embodiment of the present invention, both the second connecting piece and the first through hole are circular.
[0011] According to one embodiment of the present invention, the distance between the circumferential surface of the second connecting piece and the circumferential surface of the first through hole is greater than 0.5 mm.
[0012] According to one embodiment of the present invention, a boss is formed at the other end of the first connecting piece, and the outer surface of the boss is in contact with the inner surface of the battery casing.
[0013] According to one embodiment of the present invention, the first connecting piece is connected to the positive terminal of the battery, and the second connecting piece is connected to the negative terminal of the battery.
[0014] According to one embodiment of the present invention, the first connecting piece is connected to the negative terminal of the battery, and the second connecting piece is connected to the positive terminal of the battery.
[0015] A lithium-ion battery with a temperature-explosion-proof cover plate includes any of the temperature-explosion-proof cover plates described above. The lithium-ion battery with the temperature-explosion-proof cover plate also includes a housing. The second connecting piece, the first connecting piece, and the housing are arranged in sequence, and the first connecting piece and the housing are fixedly connected.
[0016] The beneficial effect of this utility model is that it uses a thermistor to initially control the temperature of the battery through voltage division and current limiting, thereby ensuring the basic safety of the battery.
[0017] A connecting layer is used to connect the first connecting piece and the second connecting piece, achieving connection and sealing between the first and second connecting pieces. At the same time, if the internal temperature of the battery still rises to a certain temperature after being limited by the thermal component, the heat inside the battery will melt the connecting layer, causing the second connecting piece to gradually detach from the first connecting piece, forming a pressure relief port to gradually release the internal pressure of the battery, avoiding the phenomenon of battery explosion and disintegration. Furthermore, since this pressure release is a slow pressure release, there is no explosion phenomenon, thus ensuring the safety of use.
[0018] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention.
[0019] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0020] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the following description of the embodiments with accompanying drawings, in which:
[0021] Figure 1 This is a three-dimensional schematic diagram of the overall structure of the temperature explosion-proof cover plate of this utility model;
[0022] Figure 2 This is a schematic diagram of the overall structure of the temperature explosion-proof cover of this utility model;
[0023] Figure 3 This is a cross-sectional schematic diagram of the connection between the shell and the temperature explosion-proof cover of this utility model;
[0024] Figure label:
[0025] 1. First connecting piece; 11. First through hole; 12. Boss; 2. Second connecting piece; 3. Connecting layer; 4. Thermal component; 41. Second through hole; 5. Housing. Detailed Implementation
[0026] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.
[0027] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0028] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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 mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0029] The following describes in detail, with reference to the accompanying drawings, an embodiment of the present invention: a temperature-resistant explosion-proof cover plate and a lithium-ion battery having the same.
[0030] like Figures 1-3 As shown, the temperature-resistant explosion-proof cover and the lithium-ion battery having the same according to an embodiment of the present invention include: a first connecting piece 1, a second connecting piece 2, a connecting layer 3, and a thermal component 4; the first connecting piece 1 and the second connecting piece 2 are respectively used to connect the positive and negative electrodes of the battery; the thermal component 4 is disposed at one end of the first connecting piece 1 and is electrically connected to the first connecting piece 1; the first connecting piece 1 has a first through hole 11 formed along its thickness direction; the thermal component 4 has a second through hole 41 formed along its thickness direction; the projection surface of the second through hole 41 completely covers the first through hole 11; the second connecting piece 2 is located inside the second through hole 41 and covers the first through hole 11; the connecting layer 3 is used to connect the first connecting piece 1 and the second connecting piece 2; the connecting layer 3 is a hot-melt material.
[0031] In this embodiment, the first connecting piece 1 is electrically connected to the thermal component 4. The first connecting piece 1 and the second connecting piece 2 are connected to the positive or negative terminal of the battery according to user needs. The thermal component 4 uses voltage division and current limiting to initially control the battery temperature and ensure basic battery safety. The first connecting piece 1 and the second connecting piece 2 are connected by the connecting layer 3, realizing the connection and sealing of the first connecting piece 1 and the second connecting piece 2. At the same time, if the internal temperature of the battery still rises to a certain temperature after current limiting by the thermal component 4, the heat inside the battery will melt the connecting layer 3, causing the second connecting piece 2 to gradually detach from the first connecting piece, forming a pressure relief port to gradually release the internal pressure of the battery, avoiding the phenomenon of battery explosion and disintegration. Since the pressure release is a slow pressure release, there is no explosion phenomenon, thus ensuring the safety of use.
[0032] The other end of the first connecting piece 1 is sealed to the battery casing. In other words, the thermal component 4 is located on the outside of the battery, thus avoiding corrosion of the thermal component 4 by the electrolyte when the thermal component 4 is placed inside the battery, and ensuring the service life of the thermal component 4.
[0033] The thermistor 4 is one type of PTC, preferably a PPTC (positive temperature coefficient thermistor).
[0034] When a battery is overcharged and its temperature rises to the trigger threshold, the internal resistance of the PPTC connected in series in the circuit increases sharply. On the one hand, the increased internal resistance of the PPTC, which is much greater than the battery's internal resistance, shares the voltage directly applied to the battery, thus reducing the overcharge voltage on the battery. On the other hand, the sharply increased internal resistance of the PPTC also continuously consumes the energy that is about to be input into the battery through continuous heat generation, further reducing the energy received by the battery. Both of these characteristics of the PPTC greatly reduce the energy directly input into the battery, fundamentally reducing the safety risk of battery overcharge thermal runaway. When the battery is short-circuited, the resistance of the PPTC increases sharply with the rise in battery temperature, thereby limiting the current in the circuit and protecting the circuit components. This self-recovering characteristic allows the PPTC to be reused multiple times, eliminating the need for replacement after a traditional fuse blows. Furthermore, the PPTC responds quickly to temperature changes, improving the sensitivity of battery temperature control and reducing damage to the battery from high temperatures. The PPTC can control the battery temperature between 80°C and 120°C.
[0035] The size of the second through hole 41 is larger than the size of the second connecting piece 2, so as to avoid contact with the second connecting piece 2, reduce the process of setting an insulating layer between the thermal component 4 and the second connecting piece 2, and reduce manufacturing costs.
[0036] Both the second connecting piece 2 and the first through hole 11 are circular to facilitate the installation of the second connecting piece 2 and ensure uniform coverage of the first through hole 11 by the second connecting piece 2.
[0037] The distance between the circumferential surface of the second connecting piece 2 and the circumferential surface of the first through hole 11 is greater than 0.5 mm, so as to ensure the connection width between the second connecting piece 2 and the first connecting piece 1, and to make the first connecting piece 1 and the second connecting piece 2 firmly connected.
[0038] Furthermore, the connecting layer 3 is a colloid, which can maintain the strength of the connection below 120-150 degrees Celsius. Above this temperature, the connecting layer 3 will gradually melt, thus relieving pressure. The connecting layer 3 includes, but is not limited to, materials with adhesive properties such as PP, acrylic, and epoxy.
[0039] A boss 12 is formed at the other end of the first connecting piece 1, and the outer surface of the boss 12 is in contact with the inner surface of the battery casing.
[0040] In this embodiment, the boss 12 ensures a firm connection between the first connecting piece 1 and the battery casing, preventing the first connecting piece 1 from shifting, and improving the sealing performance between the first connecting piece 1 and the battery casing after connection.
[0041] The first connecting piece 1 is connected to the positive terminal of the battery, and the second connecting piece 2 is connected to the negative terminal of the battery.
[0042] The first connecting piece 1 is connected to the negative terminal of the battery, and the second connecting piece 2 is connected to the positive terminal of the battery.
[0043] In other words, the first connecting piece 1 and the second connecting piece 2 can be connected to the positive or negative terminal of the battery according to the user's needs.
[0044] A lithium-ion battery with a temperature-explosion-proof cover includes any temperature-explosion-proof cover, and also includes a housing 5, a second connecting piece 2, a first connecting piece 1 and the housing 5 arranged in sequence, with the first connecting piece 1 and the housing 5 fixedly connected.
[0045] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0046] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.
Claims
1. A temperature-resistant explosion-proof cover, characterized in that, include: The components include a first connecting piece (1), a second connecting piece (2), a connecting layer (3), and a thermal component (4); The first connecting piece (1) and the second connecting piece (2) are used to connect the positive and negative terminals of the battery, respectively; The thermal component (4) is disposed at one end of the first connecting piece (1). The thermal component (4) is electrically connected to the first connecting piece (1). The first connecting piece (1) has a first through hole (11) formed along its thickness direction. The thermal component (4) has a second through hole (41) formed along its thickness direction. The projection surface of the second through hole (41) completely covers the first through hole (11). The second connecting piece (2) is located inside the second through hole (41) and covers the first through hole (11). The connecting layer (3) is used to connect the first connecting piece (1) and the second connecting piece (2). The connecting layer (3) is a hot melt material.
2. The temperature-resistant explosion-proof cover plate according to claim 1, characterized in that, The other end of the first connecting piece (1) is sealed to the battery casing.
3. The temperature-resistant explosion-proof cover plate according to claim 2, characterized in that, The thermal component (4) is a PTC.
4. The temperature-resistant explosion-proof cover plate according to claim 1, characterized in that, The size of the second through hole (41) is larger than the size of the second connecting piece (2) to avoid contact with the second connecting piece (2).
5. The temperature-resistant explosion-proof cover plate according to claim 4, characterized in that, Both the second connecting piece (2) and the first through hole (11) are circular.
6. The temperature-resistant explosion-proof cover plate according to claim 5, characterized in that, The distance between the circumferential surface of the second connecting piece (2) and the circumferential surface of the first through hole (11) is greater than 0.5 mm.
7. The temperature-resistant explosion-proof cover plate according to claim 2, characterized in that, The other end of the first connecting piece (1) has a boss (12) formed thereon, and the outer surface of the boss (12) is in contact with the inner surface of the battery casing.
8. The temperature-resistant explosion-proof cover plate according to claim 1, characterized in that, The first connecting piece (1) is connected to the positive terminal of the battery, and the second connecting piece (2) is connected to the negative terminal of the battery.
9. The temperature-resistant explosion-proof cover plate according to claim 1, characterized in that, The first connecting piece (1) is connected to the negative terminal of the battery, and the second connecting piece (2) is connected to the positive terminal of the battery.
10. A lithium-ion battery with a temperature-resistant explosion-proof cover, comprising the temperature-resistant explosion-proof cover as described in any one of claims 1-9, characterized in that, The device includes a housing (5), a second connecting piece (2), a first connecting piece (1), and a housing (5) arranged in sequence, with the first connecting piece (1) and the housing (5) fixedly connected.