Polymer lithium ion battery with overheating power-off function
By introducing a physical power-off mechanism using an overheat fuse in polymer lithium-ion batteries, the problem of power-off failure caused by temperature sensor malfunctions is solved, and timely power-off protection is achieved in the event of a fault.
Patent Information
- Application Number
- CN202520248626.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-17
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2035-02-17
AI Technical Summary
Existing overheat protection components for polymer lithium-ion batteries rely on temperature sensors, which are prone to failure due to malfunctions or damage, resulting in the inability to disconnect the circuit in a timely manner.
The system employs a physical power-off method using an overheat fuse. Temperature changes are transmitted through a heat-conducting plate, causing the overheat fuse to melt and control the connection between the energized spring and the positive electrode extension plate, thus achieving a power-off function that does not rely on electric triggering.
Even in the event of a temperature sensor malfunction or poor contact, the circuit can still be disconnected in time to ensure the safety of the polymer lithium-ion battery.
Smart Images
Figure CN223651610U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of lithium battery technology, and in particular to a polymer lithium-ion battery with overheat protection function. Background Technology
[0002] In the existing battery field, polymer lithium batteries use solid electrolytes, which gives them high chemical and thermal stability, making them less prone to leakage, combustion, and explosion. Compared to traditional batteries, they have higher energy density, giving them excellent energy storage capabilities. Therefore, they are widely used in various laptops and electric vehicles.
[0003] To prevent polymer lithium-ion batteries from exploding due to overheating, an overheat protection device is typically installed at the top of the battery. This device consists of a temperature sensor attached to the outer wall of the polymer lithium-ion battery, an analysis chip that controls the temperature sensor, a current-carrying spring plate soldered to the positive electrode of the polymer lithium-ion battery, a power-off telescopic device soldered below the current-carrying spring plate, and a positive electrode extension plate connected to the top of the current-carrying spring plate. The temperature sensor receives temperature changes in the battery casing. When the temperature is too high, it triggers the disconnection system of the analysis chip, causing the power-off telescopic device to retract, pulling the current-carrying spring plate away from the positive electrode extension plate, thereby breaking the circuit.
[0004] In this process, the triggering of the overheat power-off component depends on the temperature sensing of the temperature sensor. If the temperature sensor malfunctions or is damaged, the power-off telescopic device will not be able to disconnect in time. Furthermore, if the positive and negative terminals of the polymer lithium battery cannot supply power normally during the entire power-off process, the power-off telescopic device will also fail to disconnect in time. Utility Model Content
[0005] (a) Technical problems to be solved
[0006] In view of the problem that the overheat power-off component in the prior art relies on the temperature sensing of the temperature sensor and whether the positive and negative terminals of the polymer lithium battery are supplying power normally, this utility model provides a polymer lithium-ion battery with overheat power-off function, which solves the technical problem that the overheat power-off component cannot complete the power-off of the polymer lithium-ion battery when it has an open circuit.
[0007] (II) Technical Solution
[0008] To achieve the above objectives, the main technical solutions adopted by this utility model include:
[0009] This utility model embodiment provides a polymer lithium-ion battery with overheat power-off function, including a battery body, and an overheat power-off component is provided on the top of the battery body;
[0010] The overheat protection assembly includes a temperature sensor attached to the outer wall of the battery body, an analysis chip that controls the temperature sensor, a current-carrying spring plate soldered to the positive electrode of the battery body, a power-off telescopic device soldered below the current-carrying spring plate, and a positive electrode extension plate that contacts the top of the current-carrying spring plate.
[0011] An overheat protection device is provided above the energized spring sheet. The overheat protection device includes a pressure spring located above the energized spring sheet, fixed plates located at both ends of the pressure spring, an overheat fuse connecting the two fixed plates, and a heat-conducting sheet attached to one side of the overheat fuse and the outer wall of the battery body. The heat-conducting sheet passes through the cavity of the pressure spring and contacts the overheat fuse.
[0012] Optionally, the battery body includes a casing, an electrical separator located inside the casing, and a negative electrode tab and a positive electrode tab passing through the top of the casing. The energized spring sheet is welded to the top of the positive electrode tab, and the electrical separator is used to isolate the negative electrode tab and the positive electrode tab.
[0013] Optionally, the negative and positive tabs are connected to the top of the housing via an insulating sheet.
[0014] Optionally, the temperature sensor, analysis chip, and power-off telescopic device are all soldered between the negative and positive tabs via wires.
[0015] Optionally, the outer wall of the housing is fitted with a protective sleeve to protect the heat-conducting plate and the temperature sensor.
[0016] Optionally, the tab end of the housing is fitted with a sealing sleeve for protecting the overheat power-off assembly and the overheat power-off fuse assembly. The fixing plate at the top of the overheat fuse is connected to the inner side of the top of the sealing sleeve by high-temperature resistant adhesive, and the positive electrode extension plate and the negative electrode tab pass through the top of the sealing sleeve.
[0017] (III) Beneficial Effects
[0018] The beneficial effects of this utility model are as follows: The polymer lithium-ion battery with overheat protection function of this utility model adopts the physical power-off method of overheat fuse. The pressure spring fixed by the overheat fuse itself controls whether the fixing plate contacts the energized spring plate. Whether the overheat fuse melts depends on the temperature change transmitted by the heat-conducting sheet. This makes the overheat protection function of the polymer lithium-ion battery independent of electric triggering. Compared with the prior art, the overheat protection function of the polymer lithium-ion battery can still disconnect the circuit of the polymer lithium-ion battery in time when there is poor wire contact or temperature sensor failure. Attached Figure Description
[0019] Figure 1This is a schematic cross-sectional view of the overall structure of a polymer lithium-ion battery with overheat protection function according to this utility model.
[0020] Figure 2 yes Figure 1 A magnified view of a portion at point A in the middle; (modifications have been made to the attached diagram).
[0021] Figure 3 This is a schematic diagram of the overall structure of a polymer lithium-ion battery with overheat protection function according to this utility model;
[0022] Figure 4 This is an exploded view of the overall structure of a polymer lithium-ion battery with overheat protection function according to this utility model.
[0023] Figure 5 This is a schematic diagram of the overheat protection component of a polymer lithium-ion battery with overheat protection function according to this utility model.
[0024] Figure 6 yes Figure 5 A magnified view of a portion of point B in the middle.
[0025] [Explanation of reference numerals in the attached diagram] 1. Battery body; 11. Shell; 12. Electrical separator; 13. Negative electrode tab; 14. Positive electrode tab; 15. Insulating sheet; 2. Overheat protection assembly; 21. Temperature sensor; 22. Analysis chip; 23. Power-on spring; 24. Power-off telescopic device; 25. Positive electrode extension sheet; 3. Overheat protection fuse assembly; 31. Pressure spring; 32. Fixing plate; 33. Overheat fuse; 34. Heat-conducting sheet; 4. Protective sleeve; 5. Sealing sleeve. Detailed Implementation
[0026] To better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Wherein, directional terms such as "upper," "lower," etc., mentioned herein are used in a more detailed manner. Figure 1 The orientation is for reference only. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention can be understood more clearly and thoroughly, and that the scope of the present invention can be fully conveyed to those skilled in the art.
[0027] The specific implementation details are described in the following section.
[0028] Example:
[0029] Reference Figures 1 to 4The present application provides a polymer lithium-ion battery with overheat protection function, which includes a battery body 1. The battery body 1 includes a shell 11, an electrical separator 12 located inside the shell 11, and a negative electrode tab 13 and a positive electrode tab 14 passing through the top of the shell 11. The energized spring sheet 23 is welded to the top of the positive electrode tab 14. The negative electrode tab 13 and the positive electrode tab 14 are connected to the top of the shell 11 through an insulating sheet 15. The electrical separator 12 is rolled up and inserted into the shell 11 to isolate the negative electrode tab 13 and the positive electrode tab 14. Then the shell 11 is sealed. The other end of the negative electrode tab 13 and the positive electrode tab 14 extends above the top of the shell 11.
[0030] An overheat protection assembly 2 is provided above the battery body 1. The overheat protection assembly 2 includes a temperature sensor 21 attached to the outer wall of the battery body 1, an analysis chip 22 of the temperature sensor 21, a current-carrying spring 23 welded to the positive electrode of the battery body 1, a power-off extension device 24 welded below the current-carrying spring 23, and a positive electrode extension 25 in contact with the top of the current-carrying spring 23. The temperature sensor 21, the analysis chip 22, and the power-off extension device 24 are all welded between the negative electrode tab 13 and the positive electrode tab 14 via wires. The temperature sensor 21 is tightly attached to the side of the casing 11 of the battery body 1 to monitor the temperature change of the casing 11. Then, the temperature sensor 21, the analysis chip 22, and the power-off extension device 24 are... Device 24 is connected to the negative tab 13 and the positive tab 14 by wires for connecting various electrical appliances. One side of the energized spring plate 23 is soldered to the top of the positive tab 14, and the output end of the power-off telescopic device 24 is soldered to the lower middle of the energized spring plate 23. The positive extension plate 25 is located above the other end of the energized spring plate 23. Under normal conditions, the power-off telescopic device 24 is in the pushed-up state, so that the energized spring plate 23 and the positive extension plate 25 are in the connected state. However, when the temperature limit signal transmitted by the temperature sensor 21 exceeds the temperature range, the analysis chip 22 will trigger the power-off telescopic device 24, so that the power-off telescopic device 24 pulls the energized spring plate 23 down, so that the positive extension plate 25 is de-energized.
[0031] The tab end of the housing 11 is fitted with a sealing sleeve 5 that protects the overheat power-off component 2 and the overheat power-off fuse component 3. The positive electrode extension piece 25 and the negative electrode tab 13 pass through the top of the sealing sleeve 5. In order to ensure that the position of the positive electrode extension piece 25 does not change, it is usually pasted on the sealing sleeve 5. The sealing sleeve 5 is then fastened to the side wall at the top of the battery body 1 by a snap-fit structure.
[0032] Reference Figure 1 , Figures 4 to 6An overheat protection device 3 is provided above the energized spring plate 23. The overheat protection device 3 includes a pressure spring 31 located above the energized spring plate 23, fixing plates 32 located at both ends of the pressure spring 31, an overheat fuse 33 connecting the two fixing plates 32, and a heat-conducting sheet 34 attached to one side of the outer wall of the overheat fuse 33 and the battery body 1. The heat-conducting sheet 34 passes through the cavity of the pressure spring 31. The two fixing plates 32 are placed at both ends of the pressure spring 31, and the overheat fuse 33 is welded between the two fixing plates 32. At this time, the pressure spring 31 is in a compressed state. Then, one side of the heat-conducting sheet 34 passes through the side of the pressure spring 31 and is placed on one side of the overheat fuse 33. Then, the fixing plate 32 is placed at the center position above the energized spring plate 23, corresponding to the output end of the power-off telescopic device 24, and the elastic force of the pressure spring 31 is greater than the thrust of the power-off telescopic device 24.
[0033] The fixing plate 32 above the energized spring sheet 23 is connected to the bottom surface of the cavity of the sealing sleeve 5 by high-temperature resistant adhesive. The outer wall end of the housing 11 is covered with a protective sleeve 4 to protect the heat-conducting sheet 34 and the temperature sensor 21. The other end of the heat-conducting sheet 34 is placed along the outer wall of the sealing sleeve 5 and the outer wall of the housing 11. The fixing plate 32 at the top of the overheat fuse 33 is glued to the inner side of the top of the sealing sleeve 5 with high-temperature resistant adhesive to prevent the position of the fixing plate 32 from changing due to vibration during use and to ensure the stability of the overheat power-off fuse assembly 3. In order to protect the heat-conducting sheet 34 and the temperature sensor 21 from being affected by external factors, a protective sleeve 4 is put on the top of the housing 11.
[0034] In practical implementation of this invention, once the temperature sensor 21 detects that the temperature of the housing 11 exceeds the limit, it will trigger the early warning system of the analysis chip 22. The early warning system will activate the power-off extension device 24, pulling the energized spring 23 to separate it from the positive electrode extension 25, thereby achieving the overheat power-off protection function. However, when the temperature is too high, and the temperature sensor 21 is damaged or the circuit of the overheat power-off component 2 has poor contact, as the temperature of the housing 11 continues to rise, the temperature transmitted from the heat-conducting plate 34 will also rise. The overheat fuse 33 near the heat-conducting plate 34 will melt as the temperature continues to rise. This will cause the pressure spring 31 to instantly reset and press down when the overheat fuse 33 melts, thereby pressing down the energized spring 23 and disconnecting it from the positive electrode extension 25. The melting temperature of the overheat fuse 33 is greater than the early warning temperature of the temperature sensor 21.
[0035] In the description of this utility model, it should be understood that 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 indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0036] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.
[0037] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "beneath" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0038] In the description of this specification, the terms "one embodiment," "some embodiments," "embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are 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. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0039] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. A polymer lithium-ion battery with overheat protection function, comprising a battery body (1), characterized in that: An overheat protection component (2) is provided above the battery body (1); The overheat power-off assembly (2) includes a temperature sensor (21) attached to the outer wall of the battery body (1), an analysis chip (22) controlling the temperature sensor (21), a current-carrying spring sheet (23) welded to the positive electrode of the battery body (1), a power-off telescopic device (24) welded below the current-carrying spring sheet (23), and a positive electrode extension sheet (25) in contact with the top of the current-carrying spring sheet (23). An overheat protection device (3) is provided above the energized spring sheet (23). The overheat protection device (3) includes a pressure spring (31) located above the energized spring sheet (23), a fixing plate (32) located at both ends of the pressure spring (31), an overheat fuse (33) connecting the two fixing plates (32), and a heat-conducting sheet (34) attached to one side of the overheat fuse (33) and the outer wall of the battery body (1). The heat-conducting sheet (34) passes through the cavity of the pressure spring (31) and contacts the overheat fuse (33).
2. A polymer lithium-ion battery with overheat protection function as described in claim 1, characterized in that: The battery body (1) includes a housing (11), an electrical separator (12) located inside the housing (11), and a negative electrode tab (13) and a positive electrode tab (14) passing through the top of the housing (11). The energized spring sheet (23) is welded to the top of the positive electrode tab (14), and the electrical separator (12) is used to isolate the negative electrode tab (13) and the positive electrode tab (14).
3. A polymer lithium-ion battery with overheat protection function as described in claim 2, characterized in that: The negative electrode tab (13) and the positive electrode tab (14) are connected to the top of the housing (11) via an insulating sheet (15).
4. A polymer lithium-ion battery with overheat protection function as described in claim 2, characterized in that: The temperature sensor (21), the analysis chip (22), and the power-off telescopic device (24) are all soldered between the negative electrode (13) and the positive electrode (14) via wires.
5. A polymer lithium-ion battery with overheat protection function as described in claim 4, characterized in that: The outer wall of the housing (11) is fitted with a protective sleeve (4) for protecting the heat-conducting plate (34) and the temperature sensor (21).
6. A polymer lithium-ion battery with overheat protection function as described in claim 5, characterized in that: The housing (11) is fitted with a sealing sleeve (5) for protecting the overheat power-off assembly (2) and the overheat power-off fuse assembly (3). The fixing plate (32) at the top of the overheat fuse (33) is connected to the inside of the top of the sealing sleeve (5) by high-temperature resistant adhesive, and the positive electrode extension plate (25) and the negative electrode tab (13) pass through the top of the sealing sleeve (5).