Photosensitive early warning device and power battery top cover thereof

Abstract

The utility model provides a kind of photosensitive early warning device and its power battery top cover.The photosensitive early warning device of the utility model is located between explosion-proof valve and diaphragm, including reaction discoloration layer on diaphragm and substrate fixed on cover plate, substrate has photosensitive emission unit and photosensitive receiving unit, the above-mentioned photosensitive emission unit can emit corresponding light beam to reaction discoloration layer, the above-mentioned photosensitive receiving unit can read the spectral change reflected by reaction discoloration layer and can send the spectral change information read to controller.The power battery top cover includes cover plate, explosion-proof valve, diaphragm, positive pole and negative pole, the cover plate middle part has the pressure relief hole that penetrates, the above-mentioned explosion-proof valve is fixed at the lower end of pressure relief hole port, the above-mentioned diaphragm is fixed at the upper end of pressure relief hole port, the positive pole and negative pole are respectively connected at the both ends of cover plate length direction, and photosensitive early warning device is located between explosion-proof valve and diaphragm.The photosensitive early warning device can intuitively reflect whether battery is damaged.

Description

Technical Field

[0001] This utility model relates to the field of mechanical technology, specifically to a photosensitive early warning device and its power battery top cover. Background Technology

[0002] The batteries of new energy electric vehicles are equipped with battery top covers. The battery top cover is a key structural component on the upper part of the battery (especially cylindrical and square lithium-ion batteries). It is not only a physical cover, but also a multi-functional core component that integrates electrical connection, safety protection, sealing protection and thermal management.

[0003] Currently, the existing battery testing window is closed.

[0004] During production, the status of the explosion-proof valve is monitored using a transparent protective film on the cover. However, after loading, this protective film is completely sealed, making it impossible to observe the explosion-proof valve from the outside. This makes it difficult to quickly determine the status of the explosion-proof valve during transportation, and once the vehicle is put into use, it is impossible to continuously monitor the status of the explosion-proof valve.

[0005] When the explosion-proof valve is in a bulging state but has not yet reached the opening pressure, before vehicle assembly, operators need to visually identify it at close range or use CCD camera imaging to inspect it one by one. This is not only time-consuming, but also inefficient.

[0006] Furthermore, after the vehicle is put into use, the detection system is unable to monitor the status of the explosion-proof valve, which leads to a reduction in battery safety. Utility Model Content

[0007] The first objective of this invention is to address the aforementioned problems in existing technologies by providing a photosensitive early warning device that can monitor battery status in real time.

[0008] The second objective of this invention is to provide a power battery top cover that includes a photosensitive early warning device.

[0009] To achieve the first objective mentioned above, this utility model can be implemented through the following technical solutions:

[0010] A photosensitive early warning device is disposed on the top cover of a power battery. The top cover includes a long plate-shaped cover, an explosion-proof valve, and a diaphragm. The cover has a through pressure relief hole in the middle. The explosion-proof valve is fixed to the lower end of the pressure relief hole, and the diaphragm is fixed to the upper end of the pressure relief hole. The photosensitive early warning device is located between the explosion-proof valve and the diaphragm, and includes a reactive color-changing layer on the diaphragm and a substrate fixed to the cover. The substrate has a photosensitive emitting unit and a photosensitive receiving unit. The photosensitive emitting unit can emit a corresponding light beam to the reactive color-changing layer, and the photosensitive receiving unit can read the spectral changes reflected by the reactive color-changing layer and send the read spectral change information to a controller.

[0011] In the aforementioned photosensitive early warning device, the membrane is a waterproof and breathable membrane.

[0012] In the aforementioned photosensitive early warning device, the explosion-proof valve has a protruding contact portion that is directly opposite the diaphragm.

[0013] In the aforementioned photosensitive early warning device, the reactive color-changing layer is a color-changing coating located on the inner side of the membrane.

[0014] In the aforementioned photosensitive early warning device, the reactive color-changing layer is a coating located inside the membrane and containing microcapsules, wherein the microcapsules include a flexible outer shell and a color-changing substance located inside the outer shell.

[0015] In the aforementioned photosensitive early warning device, the photosensitive emitting unit is a dual-color LED light.

[0016] In the aforementioned photosensitive early warning device, the photosensitive receiving unit is a photosensitive array adjacent to the photosensitive emitting unit.

[0017] In the aforementioned photosensitive early warning device, the explosion-proof valve includes a sheet-shaped body, with a thinning zone in the middle of the body. The thickness of the thinning zone is smaller than the thickness of the body, and the aforementioned contact portion is located in the middle of the thinning zone.

[0018] In the aforementioned photosensitive early warning device, the contact part, the thinning area, and the body are an integral structure.

[0019] In the aforementioned photosensitive early warning device, the thinned area has an annular recessed groove near its edge.

[0020] To achieve the second objective mentioned above, this utility model can be implemented through the following technical solutions:

[0021] A power battery top cover includes a long plate-shaped cover, an explosion-proof valve, a diaphragm, a positive terminal post, and a negative terminal post. The cover has a through pressure relief hole in the middle. The explosion-proof valve is fixed to the lower end of the pressure relief hole, and the diaphragm is fixed to the upper end of the pressure relief hole. The positive terminal post and the negative terminal post are respectively connected to the two ends of the cover in the length direction. The feature is that a photosensitive early warning device is located between the explosion-proof valve and the diaphragm.

[0022] Compared with existing technologies, this photosensitive early warning device, under the action of the reactive color-changing coating, can add an early warning function between opening and closing the valve, further improving battery safety, reducing the possibility of overlooking potentially hazardous batteries, and the color difference between the reactive color-changing battery and a normal battery is obvious, making it easy to distinguish.

[0023] The photosensitive array is embedded in the module partition, facing the valve surface, eliminating the need for a window and enabling real-time monitoring after installation. Furthermore, the photosensitive array has its own controller, transmitting data via the existing CAN bus in seconds, completing the signal link. The photosensitive array is contactless and pressureless, causing zero damage to the valve body, while simultaneously meeting non-destructive and full lifecycle monitoring requirements.

[0024] Therefore, this solution directly fills the gap in existing technologies that "cannot be detected after installation and cannot be monitored non-destructively throughout the entire lifecycle". Attached Figure Description

[0025] Figure 1 This is a three-dimensional structural diagram of the photosensitive early warning device.

[0026] Figure 2 This is a schematic diagram of the three-dimensional structure of the photosensitive early warning device after the diaphragm is removed.

[0027] Figure 3 yes Figure 2 A cross-sectional view of the structure along line A-A.

[0028] Figure 4 This is a schematic diagram of the three-dimensional structure of the cover plate.

[0029] Figure 5 yes Figure 2 A schematic diagram of the cross-sectional structure along the B-B direction.

[0030] In the picture:

[0031] 1. Cover plate; 11. Pressure relief hole; 2. Explosion-proof valve; 21. Contact part; 22. Body; 23. Thinning area; 24. Score; 3. Diaphragm; 31. Reactive color-changing layer; 4. Substrate; 41. Photosensitive emitting unit; 42. Photosensitive receiving unit; 5. Positive electrode post; 6. Negative electrode post. Detailed Implementation

[0032] The following are specific embodiments of the present invention, and the technical solution of the present invention will be further described in conjunction with the accompanying drawings.

[0033] like Figure 1-5 As shown, the power battery top cover includes a long plate-shaped cover plate 1, an explosion-proof valve 2, and a diaphragm 3. The cover plate 1 has a through pressure relief hole 11 in the middle. The explosion-proof valve 2 is fixed to the lower end of the pressure relief hole 11, and the diaphragm 3 is fixed to the upper end of the pressure relief hole 11.

[0034] This photosensitive early warning device is located between the explosion-proof valve 2 and the diaphragm 3. It includes a reactive color-changing layer 31 on the diaphragm 3 and a substrate 4 fixed to the cover plate. The substrate 4 has a photosensitive emitting unit 41 and a photosensitive receiving unit 42. The photosensitive emitting unit 41 can emit a corresponding light beam to the reactive color-changing layer 31, and the photosensitive receiving unit 42 can read the spectral changes reflected by the reactive color-changing layer 31 and send the read spectral change information to the controller.

[0035] If the internal pressure of the battery is too high (such as thermal runaway or overcharging), the explosion-proof valve on the battery cover will rupture and release gas to prevent an explosion.

[0036] When the explosion-proof valve 2 is bulging but has not yet reached the opening pressure, before the vehicle is in use, the operator needs to visually inspect it at close range or use a CCD camera to image and check each battery individually to rule out the aforementioned problematic batteries. This photosensitive warning device creatively avoids the above manual inspection. Specifically:

[0037] When the explosion-proof valve 2 is bulging but has not yet reached the opening pressure, the explosion-proof valve 2 will apply pressure to the reaction color-changing layer 31 of the diaphragm 3. Under the above pressure, the reaction color-changing layer 31 will change color reversibly or irreversibly.

[0038] When the color-changing reaction layer 31 is not subjected to pressure, the photosensitive emitting unit 41 illuminates the color-changing reaction layer 31 and presents the set color. At this time, the photosensitive receiving unit 42 reads that the spectral change of the reaction color-changing layer 31 also conforms to the set parameter information.

[0039] Conversely, when the color-changing reaction layer 31 is subjected to pressure and changes color, the photosensitive emitting unit 41 illuminates the color-changing reaction layer 31, displaying a color other than the set value. At this time, the photosensitive receiving unit 42 reads that the spectral change at the color-changing reaction layer 31 does not conform to the set parameter information. In this state, after the aforementioned spectral change information is sent to the controller, the controller outputs a corresponding warning signal, thus intuitively informing the battery that it is in an abnormal operating state.

[0040] The membrane 3 is a waterproof and breathable membrane.

[0041] Waterproof and breathable membranes serve two purposes:

[0042] Firstly, protect the surface of the explosion-proof valve 2 to prevent it from being affected by external interference;

[0043] Secondly, maintain the air pressure in the cavity between the diaphragm 3 and the explosion-proof valve 2 to balance the air pressure with the external air pressure.

[0044] The explosion-proof valve 2 has a protruding contact portion 21 and the contact portion 21 is directly opposite the diaphragm 2.

[0045] The reactive color-changing layer 31 is a color-changing coating located inside the membrane 2.

[0046] The reactive color-changing coating 31 contains functional materials (called "color-changing materials" or "dyes") that are sensitive to specific stimuli. When the external environment changes, the molecular structure or optical properties of these materials change, thereby causing the coating color to change.

[0047] In this embodiment, the reactive color-changing layer is a spiropyran color-changing coating. It is classified as mechanochromic according to its response to stimuli. That is, under pressure or friction, the molecular arrangement or crystal structure of the reactive color-changing layer 31 changes, affecting light reflection.

[0048] The reactive color-changing layer 31 is a coating layer located inside the membrane and containing microcapsules, wherein the microcapsules include a flexible outer shell and a color-changing substance located inside the outer shell.

[0049] Microcapsules are in the form of powder or slurry, and are easily dispersed in inks or coatings. Therefore, they can be stably attached to the inside of the membrane as a coating.

[0050] The photosensitive emitting unit 41 is a dual-color LED light.

[0051] The dual-color LED lights can accurately express the color change of the reaction color-changing layer.

[0052] The photosensitive receiving unit 42 is a photosensitive array adjacent to the photosensitive emitting unit 41.

[0053] A photosensitive array is an integrated device composed of multiple photosensitive units (pixels) arranged in a regular pattern. It can simultaneously detect spatially distributed light signals, realizing the acquisition and conversion of light intensity, position, image, or spectral information. It is widely used in imaging, sensing, and other applications.

[0054] The explosion-proof valve 2 includes a sheet-shaped body 22, with a thinning zone 23 in the middle of the body 22. The thickness of the thinning zone 23 is smaller than the thickness of the body 22, and the contact portion 21 is located in the middle of the thinning zone 23.

[0055] The thinning zone 23 enables the explosion-proof valve 2 to open stably under external force.

[0056] The contact portion 21, the thinning area 23, and the body 22 are an integral structure.

[0057] This can appropriately improve the structural compactness of the explosion-proof valve 2.

[0058] The thinning area 23 has an annular recessed groove 24 near its edge.

[0059] The scoring 24 further improves the opening stability of the explosion-proof valve 2.

[0060] In this embodiment, the surface of the photosensitive receiving unit 42 is covered with a 100% solid polyurethane coating to prevent electrolyte corrosion, and the coating thickness is 150 μm. When the thinning area 23 bulges and comes into contact with the diaphragm 3, the surface color of the diaphragm 3 changes, and the photosensitive receiving unit 42 reads the change in the reflection spectrum, which is transmitted to the controller built into the photosensitive receiving unit. The controller determines whether the battery is "abnormal" or "normal". The information determined by the controller is reported to the BMS (Battery Management System) for alarm, thereby realizing real-time monitoring. Furthermore, it eliminates the need for an observation window on the battery casing corresponding to the explosion-proof valve, ensuring the integrity and airtightness of the battery casing.

[0061] This photosensitive early warning device, thanks to its reactive color-changing coating, can add an early warning function between valve opening and valve closing, further improving battery safety and reducing the possibility of overlooking potentially hazardous batteries. Moreover, the color difference between the reactive color-changing battery and a normal battery is obvious, making it easy to distinguish.

[0062] The photosensitive array is embedded in the module partition, facing the valve surface, eliminating the need for a window and enabling real-time monitoring after installation. Furthermore, the photosensitive array has its own controller, transmitting data via the existing CAN bus in seconds, completing the signal link. The photosensitive array is contactless and pressureless, causing zero damage to the valve body, while simultaneously meeting non-destructive and full lifecycle monitoring requirements.

[0063] Therefore, this solution directly fills the gap in existing technologies that are "undetectable after installation and unable to perform non-destructive full lifecycle monitoring".

[0064] The top cover of this power battery includes a long plate-shaped cover plate 1, an explosion-proof valve 2, a diaphragm 3, a positive terminal 5, and a negative terminal 6. The cover plate 1 has a through pressure relief hole 11 in the middle. The explosion-proof valve 2 is fixed to the lower end of the pressure relief hole 11, and the diaphragm 3 is fixed to the upper end of the pressure relief hole 11. The positive terminal 5 and the negative terminal 6 are respectively connected to the two ends of the cover plate 1 along its length. A photosensitive early warning device is located between the explosion-proof valve 2 and the diaphragm 3.

[0065] The above-described technical solution of this utility model addresses the problem that existing technical solutions are too simplistic and provides a solution that is significantly different from existing technologies. The parts not covered in this application's technical solution are the same as or can be implemented using existing technologies, and will not be described in detail here.

[0066] The technical solutions in the above embodiments have clearly and completely described the content of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

Claims

1. A photosensitive early warning device, disposed on the top cover of a power battery, the top cover comprising a long plate-shaped cover, an explosion-proof valve, and a diaphragm, wherein the cover has a through pressure relief hole in the middle, the explosion-proof valve is fixedly connected to the lower end of the pressure relief hole, and the diaphragm is fixedly connected to the upper end of the pressure relief hole, characterized in that, This photosensitive early warning device is located between the explosion-proof valve and the diaphragm, and includes a reactive color-changing layer on the diaphragm and a substrate fixed to the cover plate. The substrate has a photosensitive emitting unit and a photosensitive receiving unit. The photosensitive emitting unit can emit a corresponding light beam to the reactive color-changing layer, and the photosensitive receiving unit can read the spectral changes reflected by the reactive color-changing layer and send the read spectral change information to the controller.

2. The photosensitive early warning device according to claim 1, characterized in that, The membrane is a waterproof and breathable membrane.

3. The photosensitive early warning device according to claim 1, characterized in that, The explosion-proof valve has a protruding contact portion that is directly opposite the diaphragm.

4. The photosensitive early warning device according to claim 1, characterized in that, The reactive color-changing layer is a color-changing coating located on the inside of the membrane.

5. The photosensitive early warning device according to claim 1, characterized in that, The reactive color-changing layer is a coating located inside the membrane and containing microcapsules, wherein the microcapsules include a flexible outer shell and a color-changing substance located inside the outer shell.

6. The photosensitive early warning device according to claim 1, characterized in that, The photosensitive emitting unit is a dual-color LED light.

7. The photosensitive early warning device according to claim 1, characterized in that, The photosensitive receiving unit is a photosensitive array adjacent to the photosensitive emitting unit.

8. The photosensitive early warning device according to claim 3, characterized in that, The explosion-proof valve includes a sheet-shaped body with a thinning zone in the middle. The thickness of the thinning zone is smaller than the thickness of the body, and the contact portion is located in the middle of the thinning zone.

9. The photosensitive early warning device according to claim 8, characterized in that, The thinned area has an annular recessed groove near its edge.

10. A power battery top cover, characterized in that, The device includes a long plate-shaped cover, an explosion-proof valve, a diaphragm, a positive terminal, and a negative terminal. The cover has a through pressure relief hole in the middle. The explosion-proof valve is fixed to the lower end of the pressure relief hole, and the diaphragm is fixed to the upper end of the pressure relief hole. The positive terminal and the negative terminal are respectively connected to the two ends of the cover in the length direction. The photosensitive early warning device of any one of claims 1-9 is located between the explosion-proof valve and the diaphragm.

Images