A flexible sensor for monitoring battery expansion force
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-11
- Publication Date
- 2026-08-11
AI Technical Summary
[0004]但是，现有的柔性传感器需要焊接导线进行使用，制备成本高，体积一般比较小，很难应用于动力电池的监测系统中
[0018]本实用新型的柔性传感器通过Z轴导电胶层中的高导电微粒子，能在低温/常温下压接后，实现上下柔性基底和柔性线路板之间在Z轴方向上的电性导通，而保持X、Y方向上不导通。Z轴导电胶层具有互连电阻低、固化温度低、互连稳定性高等优点，再通过柔性线路板（FPC线路板）引出与采集器连接，可以大大缩小连接空间，且外观更加的整洁。本方案较传统的打端子焊线的连接方式，有效解决打端子对柔性基底的损伤及焊接对柔性基底的烫伤问题。
Smart Images
Figure CN224623884U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of flexible sensor technology, specifically to a flexible sensor for monitoring battery expansion force. Background Technology
[0002] With increasing global emphasis on environmental protection and sustainable development, the new energy vehicle industry is developing at a significantly faster pace. Batteries in new energy vehicles, under extreme conditions (high temperature, high pressure, etc.) or continuous charging and discharging, and heat release, may bulge, rupture, or even explode, seriously threatening personal and property safety. Therefore, real-time monitoring of battery pressure and temperature changes is extremely urgent.
[0003] Traditional rigid sensors are limited by the physical properties of the materials, exhibiting high hardness and brittleness, making them difficult to fit onto curved surfaces and prone to breakage under significant external forces. In contrast, flexible sensors, with their unique advantages of being lightweight, thin, flexible, bendable, and foldable, can be applied in various scenarios, closely fitting various products and devices to capture subtle changes in real time.
[0004] However, existing flexible sensors require welding wires for use, which results in high manufacturing costs and generally small size, making them difficult to apply in power battery monitoring systems. Utility Model Content
[0005] The technical problem solved by this invention is to provide a flexible sensor that is highly sensitive, low in manufacturing cost, easy to use, and applicable to power batteries.
[0006] The technical solution adopted by this utility model to solve its technical problem is:
[0007] A flexible sensor for monitoring battery expansion force includes upper and lower flexible substrates, a flexible encapsulation layer connecting and sealing the upper and lower flexible substrates, upper and lower electrode layers and upper and lower sensitive layers encapsulated inside the upper and lower flexible substrates and arranged symmetrically, and a plurality of elastic protrusions regularly arranged on the outer surface of the upper and lower flexible substrates.
[0008] The upper and lower electrode layers are formed regularly on the inner surfaces of the upper and lower flexible substrates by printing and curing. The upper and lower sensitive layers are formed regularly on the surfaces of the upper and lower electrode layers by printing and curing. The upper and lower sensitive layers are separated by the flexible encapsulation layer, forming a gap between them. The upper and lower sensitive layers are in contact under force to achieve electrical connection between the upper and lower electrode layers.
[0009] The upper and lower flexible substrates include a test terminal and a signal output terminal. The upper and lower electrode layers include an electrode test terminal and an electrode lead terminal. The electrode test terminals of the upper and lower electrode layers and the upper and lower sensitive layers are sealed inside the test terminals of the upper and lower flexible substrates through the flexible encapsulation layer. The electrode lead terminals of the upper and lower electrode layers are led out from the test terminals of the upper and lower flexible substrates to their signal output terminals.
[0010] The plurality of elastic protrusions are regularly arranged at the test end positions of the upper and lower electrode layers;
[0011] Flexible circuit boards are regularly arranged between the signal output terminals of the upper and lower flexible substrates, and the switching and electrical connection are realized through the flexible circuit boards.
[0012] Furthermore, the electrode test ends of the upper and lower electrode layers include a plurality of test electrode layers distributed in an n×m array, forming an array of a plurality of test electrode layers. The upper and lower sensitive layers are also arrayed on the array of a plurality of test electrode layers, and a plurality of sensitive layers are formed on their surfaces in the same number as the plurality of test electrode layers.
[0013] Furthermore, the plurality of elastic protrusions are arranged in an array on the outer surface of the upper and lower flexible substrates at the number and position of the arrayed plurality of test electrode layers.
[0014] Furthermore, the flexible circuit board is bonded and fixed between the signal output terminals of the upper and lower flexible substrates by a Z-axis conductive adhesive layer, and the electrode leads of the upper and lower electrode layer test terminals are electrically connected in the Z-axis direction to the leads on the flexible circuit board through highly conductive microparticles in the Z-axis conductive adhesive layer.
[0015] Furthermore, the connection between the signal output terminals of the upper and lower flexible substrates and the flexible circuit board is sealed and encapsulated using a low-pressure injection molding block or a protective film to form a sealed protective layer.
[0016] Furthermore, the thickness of the upper and lower flexible substrates is 20μm to 200μm.
[0017] Furthermore, the thickness of the plurality of elastic protrusions is 10μm to 2000μm.
[0018] This invention's flexible sensor utilizes highly conductive microparticles in its Z-axis conductive adhesive layer. After being pressed together at low / room temperature, it achieves electrical conductivity in the Z-axis direction between the upper and lower flexible substrates and the flexible circuit board, while maintaining non-conductivity in the X and Y directions. The Z-axis conductive adhesive layer offers advantages such as low interconnect resistance, low curing temperature, and high interconnect stability. Furthermore, by connecting it to the data acquisition device via a flexible circuit board (FPC), the connection space is significantly reduced, resulting in a cleaner appearance. Compared to traditional terminal crimping and soldering methods, this solution effectively solves the problems of damage to the flexible substrate caused by terminal crimping and burns to the flexible substrate caused by soldering.
[0019] The flexible sensor of this invention has a simple manufacturing process, low production cost, and is easy to mass-produce.
[0020] The flexible sensor of this invention, through the arrangement of several elastic protrusions, can improve the sensitivity of the sensor, thereby improving the sensitivity and accuracy of power battery expansion detection.
[0021] In order to enhance the firmness and reliability of the Z-axis conductive adhesive layer bonding between the upper and lower flexible substrates and the flexible circuit board, this utility model uses low-pressure injection molding blocks or protective films to encapsulate the connection points, thereby sealing and reinforcing the connection points and providing waterproof, dustproof, insulating and firm functions. Attached Figure Description
[0022] Figure 1 This is an exploded view of the flexible sensor of this utility model;
[0023] Figure 2 for Figure 1 Cross-sectional view of the flexible substrate and flexible circuit board;
[0024] in:
[0025] 11. First flexible substrate; 12. First electrode layer; 13. First sensitive layer; 14. Elastic protrusion;
[0026] 21. Second flexible substrate; 22. Second electrode layer; 23. Second sensitive layer;
[0027] 3. Flexible encapsulation layer;
[0028] 4. Flexible circuit board;
[0029] 5. Z-axis conductive adhesive layer; 51. Highly conductive microparticles. Detailed Implementation
[0030] To make the above-mentioned contents, objectives, and beneficial effects of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.
[0031] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0032] like Figure 1-2 As shown, this utility model provides a flexible sensor for monitoring battery expansion force, including upper and lower flexible substrates, a flexible encapsulation layer 3 connecting and sealing the upper and lower flexible substrates, upper and lower electrode layers and upper and lower sensitive layers encapsulated inside the upper and lower flexible substrates, and a plurality of elastic protrusions 14 regularly arranged on the outer surface of the upper and lower flexible substrates.
[0033] The upper and lower flexible substrates include the test end ( Figure 1 (left end) and signal output end ( Figure 1 The right end of the middle), the upper and lower electrode layers include the test end ( Figure 1 (left end) and lead end ( Figure 1 The test terminals of the upper and lower electrode layers and the upper and lower sensitive layers are sealed inside the test terminals of the upper and lower flexible substrates. The lead terminals of the upper and lower electrode layers are led out from the test terminals of the upper and lower flexible substrates to their signal output terminals, forming the signal output terminals of the flexible sensor.
[0034] Furthermore, the upper and lower flexible substrates include a first flexible substrate 11 and a second flexible substrate 21, the upper and lower electrode layers include a first electrode layer 12 and a second electrode layer 22, and the upper and lower sensitive layers include a first sensitive layer 13 and a second sensitive layer 23.
[0035] The upper and lower flexible substrates are made of flexible polymer materials such as polydimethylsiloxane (PDMS), polyimide (PI), polyester (PET), and polyethylene naphthalate (PEN), with a thickness of 20μm~200um.
[0036] Furthermore, the first electrode layer 12 is regularly printed on the inner surface of the first flexible substrate 11. Figure 1The lower surface of the first sensitive layer 13 is regularly printed on the surface of the test area of the first electrode layer 12. Figure 1 The lower surface of the second electrode layer 22 is regularly printed on the inner surface of the second flexible substrate 21. Figure 1 The upper surface of the second sensitive layer 23 is regularly printed on the surface of the test area of the second electrode layer 22. Figure 1 (the upper surface of the middle).
[0037] Furthermore, the first flexible substrate 11 and the second flexible substrate 21 are arranged face-to-face with the first sensitive layer 13 and the second sensitive layer 23, and the edges of the first flexible substrate 11 and the second flexible substrate 21 are sealed by the flexible encapsulation layer 3, thereby forming a sealed cavity inside them to seal the first sensitive layer 13 and the second sensitive layer 23 inside the first flexible substrate 11 and the second flexible substrate 21. The first sensitive layer 13 and the second sensitive layer 23 are separated from each other by the flexible encapsulation layer 3, forming a gap between them.
[0038] Furthermore, both the first electrode layer 12 and the second electrode layer 22 include a plurality of test electrode layers distributed in an n×m array, and the first sensitive layer 13 and the second sensitive layer 23 are also distributed in an array to form a plurality of sensitive layers equal in number to the plurality of test electrode layers. The plurality of sensitive layers are regularly printed on the surface of the plurality of test electrode layers.
[0039] The present invention discloses a flexible sensor for monitoring battery expansion force, the detection principle of which is as follows:
[0040] When the upper and lower flexible substrates are crushed, the upper and lower sensitive layers come into contact under stress, thereby forming an electrical connection between the upper and lower electrode layers and generating an electrical signal. The change in the contact area between the upper and lower sensitive layers alters the contact resistance between the upper and lower electrode layers, thus changing the generated electrical signal.
[0041] like Figure 1 As shown, a number of elastic protrusions 14 are regularly arranged in position on the outer surface of the upper and lower flexible substrates, and are disposed on the outer surface of the upper and lower flexible substrates. The elastic protrusions 14 are formed by curing a polymer material with a certain degree of elasticity, with a thickness of 10μm to 2000μm, and their shape is not limited.
[0042] Furthermore, in one embodiment, a plurality of elastic protrusions 14 are regularly disposed on the outer surface of one of the flexible substrates.
[0043] Furthermore, the front ends of the upper and lower flexible substrates are electrically connected and transferred through the flexible circuit board 4 (FPC circuit board).
[0044] like Figure 1 and Figure 2As shown, the upper and lower flexible substrates and the flexible circuit board 4 are connected and fixed together by the Z-axis conductive adhesive layer 5, thereby realizing the electrical connection and transfer between the electrode leads of the upper and lower electrode layers and the flexible circuit board 4.
[0045] Furthermore, the Z-axis conductive adhesive layer 5 contains highly conductive microparticles 51 in the Z-axis direction, enabling electrical conduction in the Z-axis direction after pressing at low / room temperature, while maintaining non-conductivity in the X and Y directions. The Z-axis conductive adhesive layer 5 has advantages such as low interconnect resistance, low curing temperature, and high interconnect stability. When led out and connected to the data collector via a flexible printed circuit board 4 (FPC), the connection space can be significantly reduced, and the appearance is cleaner. Compared to traditional terminal crimping and wire bonding methods, this solution effectively solves the problems of damage to the flexible substrate caused by terminal crimping and burns to the flexible substrate caused by welding.
[0046] Furthermore, in order to enhance the firmness and reliability of the Z-axis conductive adhesive layer bonding between the upper and lower flexible substrates and the flexible circuit board 14, the connection is encapsulated by means of low-pressure injection molding blocks or wrapping with protective film, so as to seal and protect the connection between the upper and lower flexible substrates and the flexible circuit board 14, thereby sealing and reinforcing the connection point and achieving the functions of waterproofing, dustproofing, insulation and firmness.
[0047] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above descriptions are merely specific embodiments of this utility model and are not intended to limit this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A flexible sensor for monitoring battery expansion force, characterized in that: It includes upper and lower flexible substrates, a flexible encapsulation layer connecting and sealing the upper and lower flexible substrates, upper and lower electrode layers and upper and lower sensitive layers encapsulated inside the upper and lower flexible substrates and arranged symmetrically in the upper and lower positions, and a number of elastic protrusions regularly arranged on the outer surface of the upper and lower flexible substrates. The upper and lower electrode layers are formed regularly on the inner surfaces of the upper and lower flexible substrates by printing and curing. The upper and lower sensitive layers are formed regularly on the surfaces of the upper and lower electrode layers by printing and curing. The upper and lower sensitive layers are separated by the flexible encapsulation layer, forming a gap between them. The upper and lower sensitive layers are in contact under force to achieve electrical connection between the upper and lower electrode layers. The upper and lower flexible substrates include a test terminal and a signal output terminal. The upper and lower electrode layers include an electrode test terminal and an electrode lead terminal. The electrode test terminals of the upper and lower electrode layers and the upper and lower sensitive layers are sealed inside the test terminals of the upper and lower flexible substrates through the flexible encapsulation layer. The electrode lead terminals of the upper and lower electrode layers are led out from the test terminals of the upper and lower flexible substrates to their signal output terminals. The plurality of elastic protrusions are regularly arranged at the test end positions of the upper and lower electrode layers; Flexible circuit boards are regularly arranged between the signal output terminals of the upper and lower flexible substrates, and the switching and electrical connection are realized through the flexible circuit boards.
2. The flexible sensor for monitoring battery expansion force according to claim 1, characterized in that: The electrode test ends of the upper and lower electrode layers include several test electrode layers distributed in an n×m array, forming an array of several test electrode layers. The upper and lower sensitive layers are also distributed in an array on the array of several test electrode layers, and several sensitive layers are formed on their surfaces in the same number as the several test electrode layers.
3. A flexible sensor for monitoring battery expansion force according to claim 2, characterized in that: The plurality of elastic protrusions are located at the number and position of the arrayed plurality of test electrode layers and are arranged in an array on the outer surface of the upper and lower flexible substrates.
4. A flexible sensor for monitoring battery expansion force according to any one of claims 1-3, characterized in that: The flexible circuit board is bonded and fixed between the signal output terminals of the upper and lower flexible substrates by a Z-axis conductive adhesive layer. The electrode leads of the upper and lower electrode layers are electrically connected in the Z-axis direction to the leads on the flexible circuit board through highly conductive microparticles in the Z-axis conductive adhesive layer.
5. A flexible sensor for monitoring battery expansion force according to claim 4, characterized in that: The connection between the signal output terminals of the upper and lower flexible substrates and the flexible circuit board is sealed and encapsulated by low-pressure injection molding blocks or by wrapping with protective film to form a sealed protective layer.
6. A flexible sensor for monitoring battery expansion force according to claim 4, characterized in that: The thickness of the upper and lower flexible substrates is 20μm~200μm.
7. A flexible sensor for monitoring battery expansion force according to claim 4, characterized in that: The thickness of the plurality of elastic protrusions is 10μm to 2000μm.