Battery pack safety valve dual-mode detection sensor

Abstract

The utility model discloses a dual-mode detection sensor for a safety valve of a battery pack, and the sensor comprises a PCB which is provided with a detection notch; the PCB is provided with a detection notch, the detection block is accommodated in the detection notch, a hard first micro-connection structure is connected between the first side of the detection block and the PCB, and detection supporting legs are arranged on the first micro-connection structure; the detection block can bear the impact force generated when the safety valve is opened so that the first micro-connection structure and the detection supporting foot can be broken to form a first detection signal. A second micro-connection structure is connected between the first side or the second side opposite to the first side of the detection block and the PCB, the second micro-connection structure is flexible and deformable, and detection lines are densely distributed on the back face of the detection block and used for forming a second detection signal when making contact with the electrolyte. According to the utility model, two detection modes are combined with each other, the state of the battery pack in the early stage of thermal runaway can be effectively detected, and the detection accuracy and reference are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery detection technical field especially is related to a kind of battery pack safety valve bimodulus detection sensor. BACKGROUND

[0002] With the rapid development of energy storage technology, the application of battery is more and more extensive, so the requirement for safety and reliability of battery is higher and higher. In the process of using battery, there may be serious overcharge, battery short circuit, serious over-temperature, thermal runaway, impact or extrusion deformation and piercing, etc. These problems may cause the continuous rise of the internal temperature and pressure of the battery, and when it exceeds the safety threshold, it may cause the explosion of the battery.

[0003] The battery safety valve is the last explosion-proof barrier of the battery itself. When the internal pressure of the battery reaches the opening threshold of the safety valve, for example, the opening threshold of the safety valve of lithium ion battery is usually 600-800KPa. To avoid the explosion of the battery, the battery safety valve is opened to release pressure. When the battery safety valve is opened, it means that the battery has a serious safety problem, so it is necessary to detect when the battery safety valve is opened to prevent the expansion of safety accidents.

[0004] At present, the existing sensor usually detects whether the safety valve is in the open state by detecting the electrolyte splashed when the safety valve is opened. Since the splashing direction of the electrolyte has certain uncertainty, and there is certain hysteresis in detecting the electrolyte splashed on the sensor, the detection effect is affected. UTILITARY MODEL CONTENT

[0005] In order to overcome the shortcomings of the prior art, the purpose of the utility model is to provide a kind of battery pack safety valve bimodulus detection sensor, with the advantages of good detection effect and strong reference.

[0006] The purpose of the utility model is realized by the following technical scheme:

[0007] According to the first aspect of the embodiment of the present disclosure, a kind of battery pack safety valve bimodulus detection sensor is provided, comprising:

[0008] PCB plate, the detection slot corresponding to the safety valve to be detected is opened on the PCB plate;

[0009] Detection block accommodated in the detection slot, first side of the detection block and the PCB plate are connected with the first micro-connection structure of hard, so that the detection block is suspended in the detection slot, detection leg is arranged on the first micro-connection structure, the detection block can receive the impact force of safety valve opening to make the first micro-connection structure and detection leg break and form first detection signal;

[0010] The second micro-connection structure is flexible and deformable and can maintain a connection state when an impact force is applied.

[0011] The above technical solution is implemented. When used, the PCB plate is assembled to the battery, and the detection block corresponds to the safety valve, that is, the detection block is located directly above the safety valve at a proper distance. When the safety valve of the battery pack is opened due to a failure, an upward impact force is formed and acts on the detection block. The detection block is deformed upward under the action of the impact force, and the first micro-connection structure and the detection foot are broken to generate a first detection signal. The first detection signal is a safety valve opening signal of the battery pack, and the opening detection of the safety valve is realized. At the same time, when the safety valve is opened, electrolyte is sprayed. When the electrolyte is sprayed on the back of the detection block, the detection line is in contact with the electrolyte. Since the electrolyte has good conductivity, the detection line is turned on to change the resistance value of the second detection circuit, thereby causing a voltage change to form a second detection signal. The second detection signal is a battery pack leakage detection signal. The leakage detection and opening detection can be further realized through the second detection signal. Since the first micro-connection structure is broken to realize the opening detection by directly receiving the impact force through the detection block, the detection is more rapid, the timeliness of detection is significantly improved, a faster response is provided for subsequent signal processing, the detection effect is improved, and leakage detection can be simultaneously performed after the first micro-connection structure is broken through the second micro-connection structure and the detection line. The two detection methods are combined to effectively detect the state of the battery pack in the early stage of thermal runaway, and the accuracy and reference value of detection are improved.

[0012] In some example embodiments, the first micro-connection structure includes two separately arranged connection feet, the detection line includes a first foot and a second foot arranged on the two connection feet, respectively, the first foot and the second foot are connected to the first detection circuit, and the first foot and / or the second circuit are broken to change the resistance value of the first detection circuit to form the first detection signal.

[0013] In some example embodiments, the first detection circuit includes a first detection resistor, and the first foot and the second foot are connected in parallel to the first detection resistor to change the resistance value of the first detection circuit when the first foot and / or the second foot are broken.

[0014] The first leg and / or the second leg is broken, the resistance connected with the first leg and / or the second leg is disconnected, the resistance value of the whole first detection circuit is changed, and the first detection signal is formed to complete the open valve detection.

[0015] In some example embodiments, the detection circuit includes a first circuit and a second circuit, the first circuit and the second circuit are close to each other but not in contact with each other.

[0016] The first circuit includes a first main circuit and a plurality of first branch circuits connected to the first main circuit, the second circuit includes a second main circuit and a plurality of second branch circuits connected to the second main circuit, the first main circuit substantially surrounds the second circuit and forms a detection area, the first branch circuits are located on the inner side of the first main circuit, and each of the first branch circuits and each of the second branch circuits are arranged in turn and staggered, the first branch circuits and the second branch circuits are densely arranged in the detection area, and the second main circuit is located in the middle of the detection area and the second branch circuits are located on both sides of the second main circuit.

[0017] When the battery pack fails and the safety valve is opened, the electrolyte is splashed to the detection area, the electrolyte changes the resistance impedance between the first circuit and the second circuit, changes the resistance value of the second detection circuit, causes the voltage to change, forms the second detection signal, and the second detection signal can be used as an alarm trigger signal to realize the liquid leakage detection and the open valve detection.

[0018] In some example embodiments, one end of the first main circuit forms a first connection terminal, the second main circuit extends out of the first main circuit and forms a second connection terminal, the first connection terminal and the second connection terminal are connected to the second detection circuit, and when the electrolyte contacts the detection area, the resistance impedance between the first circuit and the second circuit changes to change the parallel detection resistance value of the second detection circuit to form the second detection signal.

[0019] In some exemplary embodiments, the second main line is linear and located at the central axis of the first main line, and a plurality of second branch lines are symmetrically arranged on both sides of the second main line, one end of the second branch line being connected to the second main line and the other end extending to near the first main line.

[0020] In some exemplary embodiments, the second detection circuit comprises a second detection resistor, the second detection resistor being connected in parallel with the second detection resistor through a second micro-connection structure to change the parallel detection resistance value of the second detection circuit when the detection area contacts the electrolyte to form a second detection signal.

[0021] The above technical solutions are implemented, and when the detection area contacts the electrolyte, the impedance between the first line and the second line can be changed, and meanwhile, the changed resistance value is more obvious due to the parallel second detection resistor, so that the liquid leakage detection is realized and the detection precision is improved.

[0022] In some exemplary embodiments, the second micro-connection structure adopts a press plate process to realize the soft connection of the detection block and the PCB plate, and the thickness of the second micro-connection structure is 0.2-0.5 mm.

[0023] The above technical solutions are implemented, and the second micro-connection structure can be freely bent within at least 90° without being broken, so that the liquid leakage detection can still be realized after the first micro-connection structure is broken, and the double-mode detection effect is achieved.

[0024] In summary, compared with the prior art, the utility model has the following beneficial effects:

[0025] The utility model embodiment provides a battery pack safety valve double mode detection sensor, when using, the PCB board spare is assembled to the battery, and the detection block is corresponding with the safety valve, that is, the detection block is located just above the safety valve and is apart from the proper distance, when the battery pack fails and causes the safety valve to open, an upward impact force is formed, and acts on the detection block, the detection block is deformed upward under the action of the impact force, and then the first micro connection structure and the detection foot are broken to produce the first detection signal, the first detection signal is the battery pack safety valve opening signal, and the opening detection of the safety valve is realized, simultaneously, when the safety valve opens, the electrolyte is spouted, when the electrolyte spatters on the back of the detection block, the detection circuit is contacted with the electrolyte, since the electrolyte has good conductivity, the detection circuit is conducted and changes the resistance value of the second detection circuit, and then causes the voltage change to form the second detection signal, the second detection signal is the battery pack leakage detection signal, and the leakage detection and opening detection are further realized through the second detection signal, since the first micro connection structure is broken to realize the opening detection through the detection block directly receiving the impact force, the detection is more rapid, the detection timeliness is improved obviously, provides the faster response for subsequent signal processing, improves the detection effect, simultaneously, through the second micro connection structure and the detection circuit, after the first micro connection structure is broken, the leakage detection can be carried out simultaneously, the two detection modes are combined, can effectively detect the state of the battery pack thermal runaway early stage, improves the accuracy and the reference of detection. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is the structure schematic diagram of battery pack safety valve double mode detection sensor in the utility model embodiment.

[0027] Figure 2 It is the structure schematic diagram of first detection circuit in the utility model embodiment.

[0028] Figure 3 It is the structure schematic diagram of second detection circuit in the utility model embodiment.

[0029] Figure 4 It is the structure schematic diagram of battery pack safety valve double mode detection sensor in another utility model embodiment.

[0030] The corresponding component name represented by the figure number and letter:

[0031] 10, PCB board; 11, detection notch; 20, detection block; 21, first micro connection structure; 211, connecting leg; 22, detection leg; 221, first leg; 222, second leg; 30, second micro connection structure; 40, detection circuit; 41, first circuit; 411, first main circuit; 412, first branch circuit; 413, first terminal; 42, second circuit; 421, second main circuit; 422, second branch circuit; 423, second terminal; 50, first detection circuit; 51, first detection resistor; 60, second detection circuit; 61, second detection resistor. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0033] As shown in the drawings, Figures 1 to 3 The present embodiment provides a battery pack safety valve dual-mode detection sensor, which comprises: a PCB board 10, the PCB board 10 is provided with a detection notch 11 corresponding to a safety valve to be detected; a detection block 20 accommodated in the detection notch 11, a first micro connection structure 21 of rigidity is connected between a first side of the detection block 20 and the PCB board 10, so that the detection block 20 is suspended in the detection notch 11, detection legs 22 are arranged on connecting legs 211, the detection block 20 can receive the impact force of the opening of the safety valve to make the first micro connection structure 21 and the detection legs 22 break to form a first detection signal; a second micro connection structure 30 is connected between a second side opposite to the first side of the detection block 20 and the PCB board 10, the second micro connection structure 30 is flexible and deformable, and can maintain a connected state when receiving the impact force, and the back of the detection block 20 is densely covered with detection circuits 40 connected with the second detection circuit 60, which is used to change the parallel detection resistance value of the second detection circuit 60 when contacting the electrolyte to form a second detection signal.

[0034] Specifically, the detection block 20 is oval-shaped, the detection notch 11 is also oval-shaped as a whole corresponding to the detection, the outer edge of the detection block 20 is 1-3 mm away from the edge of the detection notch 11, the area of the detection block 20 is 1.1-1.3 times the area of the safety valve switch, and the distance between the detection block 20 and the safety valve is 1-3 mm in the normal state; preferably, the outer edge of the detection block 20 is 2 mm away from the edge of the detection notch 11, the area of the detection block 20 is 1.2 times the area of the safety valve switch, and the distance between the detection block 20 and the safety valve is 2 mm in the normal state.

[0035] The first micro-connection structure 21 comprises two separate connection legs 211, the width of the connection legs 211 is 1-2 mm, preferably 1.6 mm, the detection circuit 40 comprises a first leg 221 and a second leg 222 arranged on the two connection legs 211 respectively, the first leg 221 and the second leg 222 are connected to the first detection circuit 50, and the first leg 221 and / or the second leg 222 changes the resistance value of the first detection circuit 50 to form a first detection signal when broken.

[0036] It can be understood that the first detection circuit 50 is printed on the PCB plate 10 and the detection block 20, the first detection circuit 50 comprises a first detection resistor 51, the first leg 221 and the second leg 222 are connected in parallel with the first detection resistor 51, and the first detection resistor 51 is disconnected when the first leg 221 and / or the second leg 222 is broken, so that the resistance value of the entire first detection circuit 50 changes, thereby forming a first detection signal to complete the valve opening detection.

[0037] The thickness of the PCB plate 10 is 1.4-1.8 mm, preferably, the thickness of the PCB plate 10 is set to 1.6 mm, since the connection legs 211 are directly formed in the PCB plate 10, the thickness of the PCB plate 10 is the same as the thickness of the connection legs 211, by setting the appropriate plate thickness, the connection legs 211 have appropriate bearing performance, so that the detection block 20 can be broken to achieve valve opening detection after bearing appropriate impact force.

[0038] The second micro-connection structure 30 adopts a press plate process to realize the soft connection between the detection block 20 and the PCB plate 10, and the thickness of the second micro-connection structure 30 is 0.2-0.5 mm, preferably, the thickness of the second micro-connection structure 30 is set to 0.3 mm, which can ensure that the second micro-connection structure 30 can be freely bent within at least 90° without breaking, so that the liquid leakage detection can still be realized after the first micro-connection structure 21 is broken, achieving the effect of double-mode detection.

[0039] The detection circuit 40 comprises a first circuit 41 and a second circuit 42, the first circuit 41 and the second circuit 42 are close to each other but not in contact with each other; the first circuit 41 comprises a first main circuit 411 and a plurality of first branch circuits 412 connected to the first main circuit 411, and the second circuit 42 comprises a second main circuit 421 and a plurality of second branch circuits 422 connected to the second main circuit 421; the first main circuit 411 substantially surrounds the second circuit 42 and forms a detection area together with the second circuit 42; each first branch circuit 412 is located on the inner side of the first main circuit 411, and each first branch circuit 412 and each second branch circuit 422 are arranged in turn and staggered; the first branch circuit 412 and the second branch circuit 422 are densely arranged in the detection area; the second main circuit 421 is located in the middle of the detection area, and the second branch circuit 422 is located on both sides of the second main circuit 421.

[0040] The first main circuit 411 has a first connection end 413 at one end, the second main circuit 421 extends out of the first main circuit 411 and has a second connection end 423, and the first connection end 413 and the second connection end 423 are connected to the second detection circuit 60; when the electrolyte contacts the detection area, the resistance impedance between the first circuit 41 and the second circuit 42 changes to change the resistance value of the second detection circuit 60 to form a second detection signal.

[0041] When the battery pack fails and the safety valve opens, the electrolyte will splash onto the detection area, and the electrolyte will change the resistance impedance between the first circuit 41 and the second circuit 42, thereby changing the resistance value of the second detection circuit 60, and causing a voltage change to form a second detection signal, which can be used as an alarm trigger signal and realize liquid leakage detection and valve opening detection; since the first main circuit 411 surrounds the second circuit 42 to form a detection area, and the first branch circuit 412 and the second branch circuit 422 are densely arranged in the detection area, when the electrolyte contacts any position in the detection area, the impedance change between the first circuit 41 and the second circuit 42 can be realized, which improves the detection efficiency and detection effect; and through the arrangement form of the first branch circuit 412 and the second branch circuit 422, the circuit arrangement can be more compact, thereby realizing liquid leakage detection when a small amount of electrolyte contacts the detection area, and improving the detection accuracy.

[0042] The second main circuit 421 is linear and located at the central axis of the first main circuit 411; specifically, the second main circuit 421 can be straight or wavy, and in the embodiment, the second main circuit 421 is straight; a plurality of second branch circuits 422 are symmetrically arranged on both sides of the second main circuit 421; one end of the second branch circuit 422 is connected to the second main circuit 421, and the other end extends to the vicinity of the first main circuit 411.

[0043] The second detection circuit 60 includes a second detection resistor 61, which is connected in parallel with the second detection resistor 61 through the second micro-connection structure 30. When the detection area comes into contact with the electrolyte, the resistance value of the second detection circuit 60 is changed to form a second detection signal. When the detection area comes into contact with the electrolyte, the impedance between the first line and the second line can be changed. At the same time, the parallel second detection resistor 61 makes the change in resistance value more obvious, realizing leakage detection and improving detection accuracy.

[0044] Meanwhile, in some embodiments, both the first detection resistor 51 and the second detection resistor 61 can be connected to several precision adjustment resistors to further adjust the detection accuracy. It is understood that the first detection circuit 50 and the second detection circuit 60 are connected to the central processing unit to upload to the battery management system when a detection signal is generated.

[0045] In use, the PCB board 10 is assembled onto the battery, and the detection block 20 is aligned with the safety valve, i.e., the detection block 20 is positioned directly above the safety valve at a suitable distance. When a battery pack malfunction causes the safety valve to open, an upward impact force is generated and acts on the detection block 20. The detection block 20 deforms upward under the impact force, causing the first micro-connection structure 21 and the detection support 22 to break, generating a first detection signal. This first detection signal is the battery pack safety valve opening signal, realizing the safety valve opening detection. Simultaneously, when the safety valve opens, electrolyte is sprayed out. When the electrolyte splashes onto the back of the detection block 20, the detection circuit 40 comes into contact with the electrolyte. Due to the good conductivity of the electrolyte, the detection circuit 40 will... When conduction occurs, the resistance value of the second detection circuit 60 changes, thereby causing a voltage change and forming a second detection signal. This second detection signal is the battery pack leakage detection signal. Through this second detection signal, leakage detection and valve opening detection can be further realized. Since the first micro-connection structure 21 is broken by the impact force directly borne by the detection block 20 to realize valve opening detection, the detection is faster and the timeliness of detection is significantly improved. This provides a faster response for subsequent signal processing and improves the detection effect. At the same time, through the second micro-connection structure 30 and the detection line 40, leakage detection can also be performed simultaneously after the first micro-connection structure 21 breaks. The combination of the two detection methods can effectively detect the state of the battery pack in the early stage of thermal runaway, improving the accuracy and reference value of the detection.

[0046] like Figure 4As shown, in another embodiment, the second micro-connection structure 30 is disposed between the first side of the detection block 20 and the PCB board 10. Specifically, the two separately disposed connecting legs 211 are spaced sufficiently apart, and the second micro-connection structure 30 is located between the two connecting legs 211. Thus, there is no connection between the second side of the detection block 20 and the PCB board, and it is in a suspended state. When the safety valve opens and impacts the detection block 20, the detection block 20 bends upward, causing the connecting legs 211 to break. It can be understood that, compared to the above embodiment, since the second micro-connection structure 30 is located on the opposite side, the impact on the detection block 20 results in an upward bending direction that is opposite to the direction shown in the figure. For example, in the above embodiment, the detection block 20 bends upward along... Figure 1 The middle bends upwards from left to right, while in this embodiment, the detection block 20 bends upwards along... Figure 4 It bends upwards from right to left.

[0047] The above embodiments only illustrate several implementation methods of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the concept of this utility model. These are all equivalent modifications and improvements made to the above embodiments based on the essential technology of this utility model, and all of these fall within the protection scope of this utility model.

Claims

1. A battery pack safety valve dual mode detection sensor, characterized in that, The utility model relates to a safety valve detection device, including: PCB board spare, the detection slot for corresponding with the safety valve to be detected is opened on the PCB board spare; The detection block is accommodated in the detection slot, the first side of the detection block is connected with the PCB board spare with the first micro - connection structure of rigid, so that the detection block is suspended in the detection slot, the detection block can accept the impact force of the safety valve opening to make the first micro - connection structure and the detection foot break and form the first detection signal; The second side opposite the first side of the detection block is connected with the second micro - connection structure of the PCB board spare, the second micro - connection structure is flexible and can be deformed, and can keep the connection state when bearing the impact force, the back of the detection block is densely covered with the detection circuit connected with the second detection circuit, which is used for changing the parallel detection resistance value of the second detection circuit when contacting the electrolyte to form the second detection signal.

2. The battery pack safety valve dual mode detection sensor of claim 1, wherein, The first micro - connection structure includes two separate connection feet, the detection circuit includes first and second feet arranged in the two connection feet, the first and second feet are connected to the first detection circuit, and the resistance value of the first detection circuit is changed when the first and / or second circuits break to form the first detection signal.

3. The battery pack safety valve dual mode detection sensor of claim 2, wherein, The first detection circuit includes a first detection resistor, and the first and second feet are connected in parallel with the first detection resistor to change the resistance value of the first detection circuit when the first and / or second feet break.

4. The battery pack safety valve dual mode detection sensor of claim 1, wherein, The detection circuit includes a first circuit and a second circuit, and the first circuit and the second circuit are close to each other but not in contact with each other. The first circuit includes a first main circuit and a plurality of first branch circuits connected to the first main circuit, and the second circuit includes a second main circuit and a plurality of second branch circuits connected to the second main circuit, the first main circuit substantially surrounds the second circuit and forms a detection area, the first branch circuits are located on the inner side of the first main circuit, and each first branch circuit and each second branch circuit are arranged in turn and staggered, the first branch circuits and the second branch circuits are densely arranged in the detection area, and the second main circuit is located in the middle of the detection area, and the second branch circuits are located on both sides of the second main circuit.

5. The battery pack safety valve dual mode detection sensor of claim 4, wherein, One end of the first main circuit forms a first wiring terminal, the second main circuit extends out of the first main circuit and forms a second wiring terminal, the first wiring terminal and the second wiring terminal are connected to the second detection circuit, when the detection area contacts the electrolyte, the resistance impedance between the first circuit and the second circuit changes to change the parallel detection resistance value of the second detection circuit to form the second detection signal.

6. The battery pack safety valve dual mode detection sensor of claim 5, wherein, The second main circuit is linear and located at the central axis of the first main circuit, and a plurality of second branch circuits are symmetrically arranged on both sides of the second main circuit, one end of the second branch circuit is connected to the second main circuit, and the other end extends to the vicinity of the first main circuit.

7. The battery pack safety valve dual mode detection sensor of claim 6, wherein, The second detection circuit comprises a second detection resistor connected in parallel with the second detection resistor through a second micro-connection structure to form a second detection signal by changing the parallel detection resistance value of the second detection circuit when the detection area contacts the electrolyte.

8. The battery pack safety valve dual mode detection sensor of claim 1, wherein, The second micro-connection structure realizes the soft connection of the detection block and the PCB plate by using a pressboard process, and the thickness of the second micro-connection structure is 0.2-0.5 mm.

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