A lithium battery cover plate with an implantable sensor and a sensor packaging method

Abstract

The application discloses a lithium battery cover plate with an implantable sensor and a sensor packaging method, relates to the technical field of lithium battery internal sensing and monitoring integration, and comprises a battery shell, a cover plate assembly and a battery pole piece. A riveting assembly penetrating through the cover plate assembly is arranged between a liquid injection hole and a tab lead-out hole. A sensor assembly is arranged below the riveting assembly. The sealing unit is riveted with a three-layer composite cover plate and a T-shaped polytetrafluoroethylene gasket, forming a ring-shaped airtight channel. In combination with a PBI corrosion-resistant coating, the sealing unit has the effects of electric conduction, sealing and corrosion resistance, and improves the stability of the sensor operation. The buffer unit adopts a clamping type circular arc supporting arm structure, and flexibly buffers and disperses stress by virtue of the polytetrafluoroethylene characteristics, so that the battery pole piece is prevented from expanding and damaging the sensor. The combination of the two ensures that the lithium battery built-in sensing system can reliably, safely and long-effectively operate.

Description

Technical Field

[0001] This invention relates to the field of lithium battery internal sensing and monitoring integration technology, and in particular to a lithium battery cover plate with an implantable sensor and a sensor packaging method. Background Technology

[0002] As a core energy storage device for new energy, the real-time in-situ status of secondary lithium batteries, such as internal temperature, pressure, and electrical parameters, directly determines the battery's safety performance and cycle life. Traditional secondary lithium battery covers only achieve basic sealing and electrical conduction functions, without integrating built-in sensing and monitoring units. This fails to meet the technical requirements for online monitoring of the internal status of secondary lithium batteries, deviating from the development direction of high-safety and long-life secondary lithium batteries.

[0003] Existing implantable sensing solutions for secondary lithium batteries mostly use through-hole lead wires for direct encapsulation. The sealing structure has poor compatibility with the electrolyte environment inside the battery, which can easily lead to leakage and corrosion, causing sensor failure. At the same time, the sensor does not have a buffer protection structure adapted to the expansion of the electrode. During charging and discharging, the expansion of the electrode can easily cause mechanical damage to the sensor. The sealing reliability and structural stability during long-term service cannot meet the standards for automotive secondary lithium batteries.

[0004] In addition, conventional sensor anti-corrosion coatings lack sufficient resistance to electrolyte corrosion and density, making them prone to cracking and peeling in the high-humidity, high-salt, and highly corrosive electrolyte environment inside secondary lithium batteries. At the same time, the sensor's power supply and communication channels have low integration and complex structure, making them unsuitable for the requirements of large-scale manufacturing and long-term service of secondary lithium batteries. Therefore, there is an urgent need to provide a lithium battery cover plate with an implantable sensor and a sensor packaging method to solve the above-mentioned technical pain points. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a lithium battery cover with an implantable sensor and a sensor packaging method, thus solving the problems mentioned in the background section.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A lithium battery cover plate with an implantable sensor and a sensor packaging method are disclosed, comprising a battery casing, a cover plate assembly, and battery electrodes. The cover plate assembly is provided with a pressure relief hole, an electrode tab lead-out hole, and a liquid injection hole. A riveting assembly penetrating the cover plate assembly is provided between the liquid injection hole and the electrode tab lead-out hole. A sensor assembly is provided below the riveting assembly.

[0007] The riveting assembly and the sensor assembly form a sealing unit to ensure stable power supply and communication channels and improve sealing and corrosion resistance. A buffer unit is provided below the cover assembly to prevent the battery electrode from expanding and damaging the sensor assembly.

[0008] The sealing unit includes a through hole, which is provided on the cover plate assembly. The cover plate assembly is composed of an outer cover plate, an inner substrate layer, and an inner cover plate in sequence.

[0009] Furthermore, the outer cover plate is made of hard anodized aluminum alloy for external protection and external electrical connection, the inner substrate layer is made of modified glass fiber reinforced polyetheretherketone composite material as the overall support and main body for opening functional holes, and the inner cover plate is made of polytetrafluoroethylene composite sealing substrate, which has excellent resistance to electrolyte corrosion and long-term sealing reliability.

[0010] Furthermore, the riveting assembly includes a female rivet joint, a washer, and a male rivet joint. The riveting assembly is located inside the through hole. The female rivet joint is located on the outside of the cover plate assembly, and the male rivet joint is located on the inside of the cover plate assembly. The washer is divided into two pieces located on both sides of the cover plate assembly. The riveting assembly is composed of the female rivet joint, the washer, and the male rivet joint in sequence.

[0011] Furthermore, the gasket has a T-shaped structure, with its bottom surface width greater than the diameter of the through hole, which can form a circumferential pressing area through deformation during the riveting process. The gasket material is preferably polytetrafluoroethylene, and its thickness is designed to correspond to the riveting pressure.

[0012] Furthermore, the sensor assembly includes a flexible PI circuit substrate, on which a sensor module is mounted, a MEMS device is located in the middle of the sensor module, aluminum foil leads are mounted on the flexible PI circuit substrate, and an anti-corrosion coating is applied to the outer side of the flexible PI circuit substrate.

[0013] Furthermore, the anti-corrosion coating uses polybenzimidazole, which has excellent resistance to electrolyte corrosion and can be used for a long time in the high humidity and high salt environment inside the battery.

[0014] Furthermore, the buffer unit includes a mounting boss located inside the cover plate assembly. A buffer assembly is snapped into the lower part of the mounting boss. The buffer assembly includes a base frame with multiple locking blocks on the inner side of the base frame and locking grooves for the locking blocks on the side of the mounting boss.

[0015] Furthermore, a mounting plate is provided below the base frame, and multiple support arms are provided between the base frame and the mounting plate. A tray is provided above the mounting plate, and multiple support arms are provided between the mounting plate and the tray.

[0016] Furthermore, the support arm one, support arm two, and pallet are made of polytetrafluoroethylene, the support arm one and support arm two are both arc-shaped, and the pallet has a clearance hole in the middle.

[0017] A sensor encapsulation method for a lithium battery cover plate with an implantable sensor, using the lithium battery cover plate as described above, includes the following steps: S1: The outer cover plate, the inner substrate layer, and the inner cover plate are hot-pressed together to form a cover plate assembly. A through hole is machined between the injection hole and the tab outlet hole to penetrate the cover plate assembly. S2: Place the T-shaped gaskets on the inner and outer sides of the cover plate assembly respectively, insert the female rivet from the outside and the male rivet from the inside into the through hole, apply 500-1200N riveting pressure to plastically deform the gaskets, form a circumferential airtight sealing area around the through hole, and construct a power supply and communication connection channel that runs through the inside and outside of the cover plate assembly. S3: Fabricate sensor modules and MEMS devices on a flexible PI circuit substrate and prepare aluminum foil leads. The aluminum foil leads are made of high-purity aluminum foil material with a thickness of 10-50μm. The aluminum foil leads are connected to the male rivet joint by ultrasonic friction welding to achieve a stable electrical connection. This welding method is completed at room temperature, without the need for solder, avoiding thermal stress damage to the battery cover plastic parts and related structures during the hot welding process, and is suitable for mass automated packaging. S4: Immerse the entire sensor assembly in a polybenzimidazole (PBI) solution and apply an anti-corrosion coating evenly to the surface of the sensor assembly using an dip-coating method. S5: Place the coated sensor assembly into a vacuum oven and heat-cur it for 30 to 60 minutes under vacuum conditions of -0.2 to -0.5 bar and temperature of 85 to 100°C to make the anti-corrosion coating 17 dense and the thickness controlled at 15 to 30 μm. After the sensor assembly is prepared, use ultrasonic friction welding process to weld the aluminum foil lead wire to the male rivet joint. S6: Engage and fix the buffer assembly's locking block with the locking groove of the mounting boss on the inner side of the cover plate assembly, so that the clearance hole of the support plate fits onto the outside of the sensor assembly, forming an anti-squeezing buffer protection. S7: The cover plate assembly integrating the sensor and buffer structure is sealed and welded to the battery casing. After completing the tests on air tightness, electrical conductivity, and resistance to electrolyte corrosion, it is injected with electrolyte, sealed, and put into use.

[0018] Compared with existing technologies, the advantages of this invention are: 1. The sealing unit adopts a three-layer composite cover plate with a T-shaped PTFE gasket riveting structure. The outer layer is aluminum alloy for protection, the inner layer is polyetheretherketone for support, and the PTFE seal is PTFE. During riveting, the gasket is plastically deformed to form a circumferential airtight zone, constructing a stable and sealed power supply and communication channel. At the same time, the PBI anti-corrosion coating is resistant to electrolyte corrosion and is suitable for the high humidity and high salt environment inside the battery, ensuring the long-term stable operation of the sensor. It meets the dual requirements of conductivity and sealing and corrosion protection, improving the reliability and service life of the integrated sensing system.

[0019] 2: The buffer unit uses a snap-fit ​​mounting boss and arc support arm structure, utilizing the elasticity and insulation of polytetrafluoroethylene material to provide flexible buffer when the battery electrode expands. The double-layer support arm disperses the compressive stress, avoids damage to the sensor from mechanical impact, does not occupy extra space and is easy to install, and ensures the long-term safe operation of the lithium battery's built-in sensing and monitoring system.

[0020] In summary, the sealing unit of this invention forms a circumferential airtight channel by riveting a three-layer composite cover plate to a T-shaped polytetrafluoroethylene gasket. Combined with a PBI anti-corrosion coating, it provides electrical conductivity, sealing, and corrosion protection, thereby improving the stability of the sensor's operation. The buffer unit adopts a snap-fit ​​arc support arm structure, which uses the flexible buffering and stress dispersion properties of polytetrafluoroethylene to prevent the electrode from expanding and damaging the sensor. The combination of these two components ensures the reliable, safe, and long-term operation of the lithium battery-built-in sensing system. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a lithium battery cover plate with an implantable sensor and a sensor packaging method proposed in this invention. Figure 2 This is a half-sectional schematic diagram of the present invention; Figure 3 An exploded view of the cover plate assembly of the present invention: Figure 4 This is a completed drawing of the riveting assembly of the present invention; Figure 5 This is a partially enlarged schematic diagram A of the present invention; Figure 6 This is an exploded view of the riveting assembly of the present invention; Figure 7 This is an exploded view of the sensor assembly of the present invention; Figure 8 This is a schematic diagram of the buffer unit installation structure of the present invention; Figure 9 This is a side view of the buffer assembly of the present invention.

[0022] In the diagram: 1 Battery casing, 2 Cover plate assembly, 3 Pressure relief hole, 4 Electrode lead-out hole, 5 Liquid injection hole, 6 Riveting assembly, 7 Buffer assembly, 8 Battery electrode, 9 Outer cover plate, 10 Inner substrate layer, 11 Inner cover plate, 12 Female rivet joint, 13 Gasket, 14 Through hole, 15 Male rivet joint, 16 Sensor assembly, 17 Anti-corrosion coating, 18 Flexible PI circuit substrate, 19 Sensor module, 20 MEMS device, 21 Aluminum foil lead, 22 Mounting boss, 23 Slot, 24 Base frame, 25 Card block, 26 Mounting plate, 27 Support arm one, 28 Support arm two, 29 Support plate, 30 Clearance hole. Detailed Implementation

[0023] Reference Figures 1-9A lithium battery cover plate with an implantable sensor and a sensor packaging method are disclosed. The cover plate includes a battery shell 1, a cover plate assembly 2, and a battery electrode 8. The cover plate assembly 2 is provided with a pressure relief hole 3, an electrode tab lead-out hole 4, and a liquid injection hole 5. A riveting assembly 6 is provided between the liquid injection hole 5 and the electrode tab lead-out hole 4, and a sensor assembly 16 is provided below the riveting assembly 6.

[0024] The electrolyte injection hole 5 is used for electrolyte injection, the pressure relief hole 3 is used to install a pressure relief device to safely release pressure under overpressure conditions inside the battery, and the tab lead-out hole 4 is used to lead out the positive and negative terminals of the battery. Together with the insulating sheet, they complete the connection between the battery cell and the external circuit, forming a basic battery interface functional module.

[0025] The riveting assembly 6 and the sensor assembly 16 form a sealing unit to ensure stable power supply and communication channels and improve sealing and corrosion resistance. A buffer unit is provided below the cover assembly 2 to prevent the battery electrode 8 from expanding and damaging the sensor assembly 16.

[0026] The sealing unit includes a through hole 14, which is located on the cover plate assembly 2. The cover plate assembly 2 is composed of an outer cover plate 9, an inner substrate layer 10, and an inner cover plate 11 in sequence.

[0027] The outer cover plate 9 is made of hard anodized aluminum alloy, used for external protection and external electrical connection. The inner substrate layer 10 is made of modified glass fiber reinforced polyetheretherketone composite material, serving as the overall support and the main body for functional hole opening. The inner cover plate 11 is made of polytetrafluoroethylene composite sealing substrate, possessing excellent resistance to electrolyte corrosion and long-term sealing reliability. The preparation method of modified glass fiber reinforced polyether ether ketone composite material is as follows: First, PEEK resin powder is dried at 80 to 100°C to remove water, then mixed with short glass fibers activated by coupling agent and compatibility modifier according to the formula, fed into a twin-screw extruder, melt-blended at 360 to 390°C, extruded and granulated, the granules are dried a second time and then molded or injection molded, the mold temperature is controlled at 160~200°C to ensure full crystallization, and finally annealed to relieve stress, to obtain a high-strength, high-insulation, and electrolyte-resistant glass fiber reinforced polyether ether ketone composite material.

[0028] The riveting assembly 6 includes a female riveting joint 12, a gasket 13, and a male riveting joint 15. The riveting assembly 6 is located inside the through hole 14. The female riveting joint 12 is located on the outside of the cover plate assembly 2, and the male riveting joint 15 is located on the inside of the cover plate assembly 2. The gasket 13 is divided into two pieces located on both sides of the cover plate assembly 2. The riveting assembly 6 is composed of the female riveting joint 12, the gasket 13, and the male riveting joint 15 in sequence.

[0029] The male rivet 15 and the female rivet 12 are axially aligned and pass through the through hole of the cover plate. They are mechanically locked and electrically connected by press riveting. The male rivet 15 is located on the inner side of the cover plate and is connected to the aluminum foil lead wire 21. The female rivet 12 is located on the outer side of the cover plate and is connected to the external monitoring equipment.

[0030] The gasket 13 has a T-shaped structure, and its bottom width is greater than the diameter of the through hole 14. It can form a circumferential pressing area through deformation during the riveting process. The gasket 13 is preferably made of polytetrafluoroethylene, and its thickness is designed to correspond to the riveting pressure.

[0031] A T-shaped sealing gasket 13 is provided between the male and female rivet joints. The gasket 13 includes an upper gasket and a lower gasket, which are respectively attached to the inner and outer surfaces of the cover plate to buffer the riveting deformation and form an airtight sealing structure. The sealing gasket is made of polytetrafluoroethylene (PTFE) material with a thickness of 0.5–2 mm to maintain the structural integrity of the cover plate while ensuring the deformation absorption capacity.

[0032] To avoid localized bulging or deformation of the cover plate due to excessive riveting pressure or an excessively thin gasket, the riveting pressure is preferably controlled within the range of 500–1200 N. When the thickness of the PTFE gasket is less than 0.5 mm or the riveting pressure exceeds the above range, it will cause the T-shaped structure seal or cover plate insulation to fail, thereby affecting the overall reliability of the battery.

[0033] The sensor assembly 16 includes a flexible PI circuit substrate 18, a sensor module 19 is disposed on the flexible PI circuit substrate 18, a MEMS device 20 is disposed in the middle of the sensor module 19, aluminum foil leads 21 are disposed on the flexible PI circuit substrate 18, and an anti-corrosion coating 17 is coated on the outer side of the flexible PI circuit substrate 18.

[0034] The sensor module 19 can be distributed in different riveting channel positions as needed to form an array layout, supporting synchronous monitoring of parameters such as temperature, air pressure, and conductivity at multiple points.

[0035] The anti-corrosion coating 17 uses polybenzimidazole, which has excellent resistance to electrolyte corrosion and can be used for a long time in the high humidity and high salt environment inside the battery.

[0036] The buffer unit includes a mounting boss 22, which is located inside the cover plate assembly 2. A buffer assembly 7 is snapped into the lower part of the mounting boss 22. The buffer assembly 7 includes a base frame 24. Multiple locking blocks 25 are provided inside the base frame 24. The side of the mounting boss 22 is provided with a locking groove 23 that matches the locking blocks 25.

[0037] A mounting plate 26 is provided below the base frame 24, and multiple support arms 27 are provided between the base frame 24 and the mounting plate 26. A support plate 29 is provided above the mounting plate 26, and multiple support arms 28 are provided between the mounting plate 26 and the support plate 29.

[0038] The support arm 27, support arm 28 and pallet 29 are made of polytetrafluoroethylene. Support arm 27 and support arm 28 are both arc-shaped, and pallet 29 has a clearance hole 30 in the middle.

[0039] An avoidance hole 30 is provided in the middle of the support plate 29 to avoid affecting the sensor's detection of the internal condition of the battery. When the battery electrode 8 expands, the double-layer arc-shaped support arm flexibly deforms and disperses the stress to prevent the sensor assembly 16 from being squeezed and damaged.

[0040] A sensor encapsulation method for a lithium battery cover plate with an implantable sensor, using the lithium battery cover plate as described above, includes the following steps: S1: The outer cover plate 9, the inner substrate layer 10, and the inner cover plate 11 are hot-pressed together to form a cover plate assembly 2. A through hole 14 is machined between the liquid injection hole 5 and the electrode lead-out hole 4, penetrating the cover plate assembly 2. S2: Place the T-shaped gasket 13 on the inner and outer sides of the cover plate assembly 2 respectively, insert the female rivet 12 from the outside and the male rivet 15 from the inside into the through hole 14, apply 500~1200N riveting pressure to plastically deform the gasket 13, form a circumferential airtight sealing area around the through hole 14, and construct a power supply and communication connection channel that runs through the inside and outside of the cover plate assembly 2. S3: A sensor module 19 and a MEMS device 20 are fabricated on a flexible PI circuit substrate 18, and an aluminum foil lead 21 is prepared. The aluminum foil lead 21 is made of high-purity aluminum foil material with a thickness of 10-50μm. The aluminum foil lead 21 is connected to the male rivet 15 by ultrasonic friction welding to achieve a stable electrical connection. This welding method is completed at room temperature, without the need for solder, and avoids thermal stress damage to the battery cover plastic parts and related structures during the hot welding process. It is suitable for mass automated packaging. S4: Immerse the sensor assembly 16 entirely in the polybenzimidazole PBI solution, and apply an anti-corrosion coating 17 evenly to the surface of the sensor assembly 16 by dip coating. S5: Place the coated sensor assembly 16 into a vacuum oven and heat-cur it for 30 to 60 minutes under vacuum conditions of -0.2 to -0.5 bar and temperature of 85 to 100°C to make the anti-corrosion coating 17 densely formed with a thickness of 15 to 30 μm. After the sensor assembly 16 is prepared, use ultrasonic friction welding process to weld the aluminum foil lead wire 21 to the male rivet joint 15. S6: The latch 25 of the buffer assembly 7 is engaged and fixed with the slot 23 of the mounting boss 22 on the inner side of the cover plate assembly 2, so that the clearance hole 30 of the support plate 29 is fitted onto the outside of the sensor assembly 16 to form an anti-squeezing buffer protection. S7: The cover plate assembly 2, which integrates the sensor and buffer structure, is sealed and welded to the battery casing 1. The airtightness, conductivity, and resistance to electrolyte corrosion are tested. After passing the tests, the battery is injected, sealed, and put into use.

[0041] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A lithium battery cover with an implantable sensor, comprising a battery casing (1), a cover assembly (2), and battery electrodes (8), characterized in that, The cover plate assembly (2) is provided with a pressure relief hole (3), an electrode lead-out hole (4) and a liquid injection hole (5). A riveting assembly (6) that penetrates the cover plate assembly (2) is provided between the liquid injection hole (5) and the electrode lead-out hole (4). A sensor assembly (16) is provided below the riveting assembly (6). The riveting assembly (6) and the sensor assembly (16) form a sealing unit to ensure stable power supply and communication channels and improve sealing and corrosion resistance. A buffer unit is provided below the cover plate assembly (2) to prevent the battery electrode (8) from expanding and damaging the sensor assembly (16). The sealing unit includes a through hole (14), which is provided on the cover plate assembly (2). The cover plate assembly (2) is composed of an outer cover plate (9), an inner substrate layer (10), and an inner cover plate (11) in sequence.

2. A lithium battery cover with an implantable sensor according to claim 1, characterized in that, The outer cover plate (9) is made of hard anodized aluminum alloy and is used for external protection and external electrical connection. The inner substrate layer (10) is made of modified glass fiber reinforced polyether ether ketone composite material and serves as the main body for overall support and functional hole opening. The inner cover plate (11) is made of polytetrafluoroethylene composite sealing substrate, which has excellent resistance to electrolyte corrosion and long-term sealing reliability.

3. A lithium battery cover with an implantable sensor according to claim 1, characterized in that, The riveting assembly (6) includes a female riveting head (12), a gasket (13), and a male riveting head (15). The riveting assembly (6) is located inside the through hole (14). The female riveting head (12) is located on the outside of the cover plate assembly (2). The male riveting head (15) is located on the inside of the cover plate assembly (2). The gasket (13) is divided into two pieces located on both sides of the cover plate assembly (2). The riveting assembly (6) is composed of the female riveting head (12), the gasket (13), and the male riveting head (15) in sequence.

4. A lithium battery cover with an implantable sensor according to claim 3, characterized in that, The gasket (13) has a T-shaped structure, and its bottom width is greater than the diameter of the through hole (14). It can form a circumferential pressing area through deformation during the riveting process. The gasket (13) is preferably made of polytetrafluoroethylene, and its thickness is designed to correspond to the riveting pressure.

5. A lithium battery cover with an implantable sensor according to claim 1, characterized in that, The sensor assembly (16) includes a flexible PI circuit substrate (18), on which a sensor module (19) is provided, and a MEMS device (20) is provided in the middle of the sensor module (19). An aluminum foil lead (21) is provided on the flexible PI circuit substrate (18), and an anti-corrosion coating (17) is coated on the outside of the flexible PI circuit substrate (18).

6. A lithium battery cover with an implantable sensor according to claim 5, characterized in that, The anti-corrosion coating (17) is made of polybenzimidazole, which has excellent resistance to electrolyte corrosion and can be used for a long time in the high humidity and high salt environment inside the battery.

7. A lithium battery cover with an implantable sensor according to claim 1, characterized in that, The buffer unit includes a mounting boss (22), which is located inside the cover plate assembly (2). A buffer assembly (7) is snapped into the bottom of the mounting boss (22). The buffer assembly (7) includes a base frame (24). Multiple locking blocks (25) are provided inside the base frame (24). The side of the mounting boss (22) is provided with a locking groove (23) that matches the locking blocks (25).

8. A lithium battery cover with an implantable sensor according to claim 7, characterized in that, The base frame (24) is provided with a mounting plate (26) below it. Multiple support arms (27) are provided between the base frame (24) and the mounting plate (26). A tray (29) is provided above the mounting plate (26). Multiple support arms (28) are provided between the mounting plate (26) and the tray (29).

9. A lithium battery cover with an implantable sensor according to claim 8, characterized in that, The support arm 1 (27), support arm 2 (28) and tray (29) are made of polytetrafluoroethylene. The support arm 1 (27) and support arm 2 (28) are both arc-shaped. The tray (29) has a clearance hole (30) in the middle.

10. A sensor encapsulation method for a lithium battery cover with an implantable sensor, using the lithium battery cover as described in any one of claims 1-9, comprising the following steps: S1: The outer cover plate (9), the inner substrate layer (10), and the inner cover plate (11) are hot-pressed together to form a cover plate assembly (2), and a through hole (14) is machined between the liquid injection hole (5) and the electrode lead-out hole (4) to penetrate the cover plate assembly (2). S2: Place the T-shaped gasket (13) on the inner and outer sides of the cover plate assembly (2), insert the female rivet (12) from the outside and the male rivet (15) from the inside into the through hole (14), apply 500~1200N riveting pressure, so that the gasket (13) is plastically deformed, forming a circumferential airtight sealing area around the through hole (14), and constructing a power supply and communication electrical connection channel that runs through the inside and outside of the cover plate assembly (2); S3: A sensor module (19) and MEMS device (20) are fabricated on a flexible PI circuit substrate (18), and an aluminum foil lead (21) is prepared. The aluminum foil lead (21) is made of high-purity aluminum foil material with a thickness of 10-50 μm. The aluminum foil lead (21) is connected to the male rivet joint (15) by ultrasonic friction welding. This welding method is completed at room temperature and does not require solder. It avoids thermal stress damage to the battery cover plastic parts and related structures during the hot welding process and is suitable for batch automated packaging. S4: Immerse the sensor assembly (16) in a polybenzimidazole (PBI) solution and apply an anti-corrosion coating (17) evenly to the surface of the sensor assembly (16) by dip coating. S5: Place the coated sensor assembly (16) into a vacuum oven and heat cure it for 30 to 60 minutes under vacuum conditions of -0.2 to -0.5 bar and temperature of 85 to 100°C, so that the anti-corrosion coating (17) is densely formed and the thickness is controlled at 15 to 30 μm. After the sensor assembly (16) is prepared, use ultrasonic friction welding process to weld the aluminum foil lead wire (21) to the male rivet joint (15). S6: The latch (25) of the buffer assembly (7) is engaged and fixed with the slot (23) of the mounting boss (22) on the inner side of the cover plate assembly (2), so that the clearance hole (30) of the tray (29) is fitted onto the outside of the sensor assembly (16) to form an anti-squeezing buffer protection. S7: The cover plate assembly (2) integrating the sensor and buffer structure is sealed and welded to the battery shell (1). The air tightness, conductivity and resistance to electrolyte corrosion are tested. After passing the test, the battery is injected and sealed for use.

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