Integrated composite battery top cover

Abstract

The application relates to the technical field of battery top covers, and discloses an integrated composite battery top cover which comprises a top cover main body, a lower plastic, a separation assembly and two pole columns; the separation assembly is installed between the top cover main body and the lower plastic, two loading holes are formed in the top cover main body, and the two pole columns pass through the lower plastic and the separation assembly and are respectively installed in the two loading holes; the separation assembly comprises a separation piece and a high-temperature-resistant part; the separation piece is installed at the bottom of the top cover main body and forms a composite cover plate structure with the top cover main body; the high-temperature-resistant part is connected to the bottom of the separation piece; and the shape of the lower plastic is matched with the shape of the separation piece. The composite cover plate structure is constructed through the separation assembly, the strength of the top cover and the heat-resistant isolation capacity are enhanced, the inert gas is pre-stored in the convex shell, the high-temperature self-triggering exhaust sealing piece is used, the fire is quickly extinguished when a short circuit occurs, the elastic gas pushing part is used for energy storage and boosting, the gas injection is accelerated, and the battery thermal runaway protection and early fire extinguishing efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of battery top cover technology, and more particularly to an integrated composite battery top cover. Background Technology

[0002] The battery top cover is a key structural component in energy storage devices such as lithium-ion batteries and power batteries. Located on top of the battery casing, it performs multiple functions, including sealing and safety protection. The battery top cover is usually composed of components such as a top cover sheet, positive terminal, negative terminal, and explosion-proof valve. The top cover sheet is generally made of aluminum and formed by stamping, welding and other processes. Battery top covers are widely used in new energy vehicle power batteries, consumer electronics lithium batteries, energy storage power station battery modules and other fields.

[0003] If an internal short circuit or other abnormal situation occurs during the use of the battery cell, the cell temperature will rise rapidly, causing the lower plastic component at the bottom of the battery cover to melt. After the plastic melts, the insulation between the battery cover and the cell will be lost, causing the cover to directly contact the cell and triggering a wider short circuit. In severe cases, it may even induce a fire risk. Existing battery covers lack an effective isolation structure between the cover and the cell, making it difficult to prevent the thermal runaway propagation process.

[0004] To address the aforementioned issues, this application proposes an integrated composite battery top cover. Summary of the Invention

[0005] This invention proposes an integrated composite battery top cover, which solves the problems in related technologies where short circuits in the battery cell cause the lower plastic to melt and fail, the top cover directly contacts the battery cell, leading to a large-area short circuit and the risk of thermal runaway and fire, and the lack of effective isolation and protection in existing structures.

[0006] The present invention proposes an integrated composite battery top cover, comprising a top cover body, a lower plastic, a separator component, and two terminals;

[0007] The separator assembly is installed between the top cover body and the lower plastic. The top cover body has two loading holes, and the two poles pass through the lower plastic and are respectively installed in the two loading holes with the separator assembly.

[0008] The partition assembly includes a partition and a high-temperature resistant part. The partition is installed at the bottom of the top cover body and forms a composite cover structure with it. The high-temperature resistant part is connected to the bottom of the partition. The shape of the lower plastic is adapted to the shape of the partition.

[0009] As a further optimization of the present invention, the separator includes a separator plate, the bottom of which is integrally formed with a raised frame and two raised shells, and the raised frame is located between the two raised shells, and both the raised shells and the raised frame extend into the lower plastic.

[0010] As a further optimization of the present invention, the high-temperature resistant part includes a first high-temperature resistant tape and a second high-temperature resistant tape. The bottom of the raised shell is attached with the first high-temperature resistant tape, and the bottom of the partition plate and the raised frame are both attached with the second high-temperature resistant tape.

[0011] As a further optimization of the present invention, a cavity is provided inside the protruding shell, and an injection component for injecting inert gas into the cavity is installed on the top of the cavity. Openings facing the pole are provided on both sides of the inner wall of the lower plastic. An exhaust seal is installed on the side of the protruding shell, which communicates with the cavity and faces the opening.

[0012] As a further optimization of the present invention, the air injection assembly includes a sealing plate and an elastic air-thrusting part. A sealing plate is installed on the top of the cavity to seal its interior, and an elastic air-thrusting part located inside the cavity is installed on the bottom of the sealing plate. An air injection pipe passing through the elastic air-thrusting part is installed on the sealing plate, and a valve is installed on the air injection pipe.

[0013] As a further optimization of the present invention, the elastic air-thrusting part includes a spring and a push plate. The bottom of the sealing plate is equipped with a push plate located in the cavity via a spring, and the push plate is slidably sleeved on the air injection pipe.

[0014] As a further optimization of the present invention, the exhaust seal includes an exhaust cover, and the side of the protruding shell is equipped with an exhaust cover that communicates with the cavity and is arranged toward the opening. The side of the exhaust cover is detachably connected with a plurality of spaced sealing portions.

[0015] As a further optimization of the present invention, the sealing part includes an exhaust shaft, and the side of the exhaust cover is provided with a plurality of threaded holes arranged at intervals, each of which is threaded with an exhaust shaft, and the end of the exhaust shaft is connected with a sealing membrane.

[0016] As a further optimization of the present invention, the partition plate is provided with insertion holes on both sides, and the bottom sides of the top cover body are fixed with limiting posts, and the limiting posts on the bottom sides of the top cover body are respectively inserted into the insertion holes on both sides of the partition plate.

[0017] As a further optimization of the present invention, the material of the partition plate includes, but is not limited to, steel.

[0018] The above-described technical solution of the present invention has the following beneficial technical effects:

[0019] 1. This invention installs a partition assembly between the top cover body and the lower plastic, and the partition assembly consists of a partition and a high-temperature resistant part. The partition is installed at the bottom of the top cover body and forms a composite cover structure with it. The composite structure can improve the overall strength and effectively resist the internal pressure of the battery cell and external impact. The partition plays a role in separating the top cover body and the lower plastic, maintaining a certain distance between the top cover body and the lower plastic. A high-temperature resistant part is connected to the bottom of the partition, which can play a role in high temperature resistance. The above design enhances the structural strength and heat insulation capability of the top cover assembly through the synergistic effect of the composite cover structure and the high-temperature resistant part. Even if the lower plastic melts due to abnormal high temperature of the battery cell, the partition can still maintain an effective insulation gap between the top cover body and the battery cell, thereby inhibiting the spread of thermal runaway and reducing the risk of fire.

[0020] 2. The bottom of the separator plate of the present invention is integrally formed with a raised shell extending into the lower plastic, and the inner walls on both sides of the lower plastic are provided with openings that are directly opposite to the electrode post. The side of the raised shell is equipped with an exhaust seal that is directly opposite to the opening. In use, inert gas is injected into the cavity inside the raised shell through the gas injection component. If the cell short circuits, causing the internal temperature to rise and ignite, the exhaust seal will break under the action of high temperature, and the gas inside the raised shell will be discharged through the exhaust seal to extinguish the fire. The above design utilizes the high temperature self-triggered exhaust seal breakage mechanism to release the inert gas pre-stored in the cavity of the raised shell to the short circuit ignition site of the cell, realize early and rapid fire extinguishing, and effectively prevent the flame from spreading to the entire battery module.

[0021] 3. When inert gas is injected into the cavity through the injection pipe in the injection assembly, the elastic thrust part at the bottom of the sealing plate moves upward under the action of the gas. When the exhaust seal is venting, the elastic thrust part can promote the rapid discharge of gas in the cavity. The elastic thrust part designed above automatically stores energy during gas injection and actively applies thrust at the moment the exhaust seal breaks, accelerating the injection rate and coverage of the inert gas, thereby improving the fire extinguishing response speed and the efficiency of suppressing thermal runaway. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of an integrated composite battery top cover proposed in this invention;

[0023] Figure 2 This is a schematic diagram of the bottom structure of an integrated composite battery top cover proposed in this invention;

[0024] Figure 3 This is a schematic diagram of the disassembled structure of an integrated composite battery top cover proposed in this invention;

[0025] Figure 4 This is a schematic diagram of the disassembled structure of the lower plastic and the separator component in this invention;

[0026] Figure 5 This is a schematic diagram of the bottom structure of the partition plate in this invention;

[0027] Figure 6 This is a schematic diagram of the top structure of the partition plate in this invention;

[0028] Figure 7 This is a schematic diagram of the disassembled structure of the partition plate and the gas injection assembly in this invention;

[0029] Figure 8 This is a schematic diagram of the gas injection assembly in this invention;

[0030] Figure 9 This is a schematic diagram of the exhaust seal in this invention;

[0031] Figure 10 This is a schematic diagram of the sealing part in this invention;

[0032] Figure 11 This is a schematic diagram of the disassembled structure of the top cover body and the partition plate in this invention.

[0033] Reference numerals: 1. Top cover body; 101. Limiting post; 2. Lower plastic; 21. Opening; 3. Separator assembly; 31. Separator; 311. Separator plate; 3111. Insertion hole; 312. Protruding shell; 3121. Cavity; 313. Protruding frame; 32. High temperature resistant part; 321. First high temperature resistant tape; 322. Second high temperature resistant tape; 4. End post; 5. Air injection assembly; 51. Sealing plate; 52. Elastic air pushing part; 521. Spring; 522. Push plate; 53. Air injection pipe; 531. Valve; 6. Exhaust sealing part; 61. Exhaust hood; 62. Sealing part; 621. Exhaust shaft; 622. Sealing membrane. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0035] like Figure 1-11 As shown, the present invention proposes an integrated composite battery top cover, which includes a top cover body 1, a lower plastic 2, a separator component 3, and two terminal posts 4;

[0036] The separator assembly 3 is installed between the top cover body 1 and the lower plastic 2. Two loading holes are opened on the top cover body 1. Two pole posts 4 pass through the lower plastic 2 and are respectively installed in the two loading holes with the separator assembly 3.

[0037] The partition assembly 3 includes a partition 31 and a high-temperature resistant part 32. The partition 31 is installed at the bottom of the top cover body 1 and forms a composite cover structure with it. The high-temperature resistant part 32 is connected to the bottom of the partition 31. The shape of the lower plastic 2 is adapted to the shape of the partition 31.

[0038] The lower plastic 2 provides initial insulation and sealing. The separator 3 is sandwiched between the top cover body 1 and the lower plastic 2. The separator 31 and the top cover body 1 form a composite cover structure, which can improve the overall structural strength of the top cover and effectively resist the internal pressure of the battery cell and external impact. The high-temperature resistant part 32 is attached to the bottom of the separator 31 and faces the high-temperature area of ​​the battery cell directly, forming a high-temperature resistant isolation layer. This structure allows the separator 31 to maintain the insulation distance between the top cover body 1 and the battery cell even after the lower plastic 2 fails due to heat melting, avoiding direct contact that could cause a secondary short circuit and reducing the risk of thermal runaway and fire.

[0039] In this embodiment, the separator 31 includes a separator plate 311. The bottom of the separator plate 311 is integrally formed with a protruding frame 313 and two protruding shells 312, and the protruding frame 313 is located between the two protruding shells 312. Both the protruding shells 312 and the protruding frame 313 extend into the lower plastic 2.

[0040] The partition plate 311 and the top cover body 1 form a composite bearing layer. The raised shell 312 and the raised frame 313 extend downward into the lower plastic 2 to achieve fitting and positioning with the lower plastic 2, improve the assembly tightness, and the raised shell 312 and the raised frame 313 can maintain the distance between the top cover body 1 and the lower plastic 2.

[0041] The raised bracket 313 is placed between the two raised shells 312, serving as an intermediate support and isolating the positive and negative electrodes to prevent short-circuiting at the positive electrode; the raised bracket 313 also enhances the overall rigidity of the partition plate 311. The one-piece molded structure reduces assembly gaps, improves heat insulation and structural stability, and prevents component misalignment at high temperatures.

[0042] In this embodiment, the high-temperature resistant part 32 includes a first high-temperature resistant tape 321 and a second high-temperature resistant tape 322. The bottom of the protruding shell 312 is attached with the first high-temperature resistant tape 321, and the bottom of the partition plate 311 and the protruding frame 313 are both attached with the second high-temperature resistant tape 322.

[0043] The first high-temperature resistant tape 321 covers the bottom of the raised shell 312, and the second high-temperature resistant tape 322 covers the bottom of the partition plate 311 and the raised frame 313, forming a fully covered high-temperature resistant layer. When the battery cell heats up abnormally, the first high-temperature resistant tape 321 and the second high-temperature resistant tape 322 simultaneously block the upward conduction of heat, preventing the high temperature from directly acting on the joint surface between the top cover body 1 and the lower plastic 2. The bottom of the partition plate 311, the raised shell 312, and the raised frame 313 are fully wrapped and protected, which can slow down the heat melting speed of the lower plastic 2. Even if the lower plastic 2 melts, the first high-temperature resistant tape 321 and the second high-temperature resistant tape 322 still maintain the insulation and isolation effect, improving the heat resistance life of the top cover body 1.

[0044] In this embodiment, a cavity 3121 is provided inside the protruding shell 312. An injection component 5 for injecting inert gas into the cavity 3121 is installed on the top of the cavity 3121. Openings 21 are provided on both sides of the inner wall of the lower plastic 2, which are arranged toward the pole post 4. An exhaust sealing component 6 is installed on the side of the protruding shell 312, which communicates with the cavity 3121 and is arranged toward the opening 21.

[0045] Cavity 3121 serves as an inert gas storage chamber, and is filled and sealed by the gas injection assembly 5;

[0046] The opening 21 of the lower plastic 2 is directly opposite the high-risk area of ​​short circuits around the electrode post 4. The exhaust seal 6 is aligned with the opening 21 to form a directional spray path. When the battery cell short-circuits and catches fire, and the temperature rises sharply, the exhaust seal 6 is triggered and damaged by the high temperature. The inert gas in the cavity 3121 is directly sprayed towards the fire source around the electrode post 4 through the exhaust seal 6 and the opening 21. This directional spray design can achieve early fire suppression, prevent the flame from spreading along the electrode post 4, and inhibit the rapid spread of thermal runaway.

[0047] In this embodiment, the air injection assembly 5 includes a sealing plate 51 and an elastic air-thrusting part 52. The top of the cavity 3121 is equipped with a sealing plate 51 that seals its interior. The bottom of the sealing plate 51 is equipped with an elastic air-thrusting part 52 located inside the cavity 3121. An air injection pipe 53 passing through the elastic air-thrusting part 52 is installed on the sealing plate 51. A valve 531 is installed on the air injection pipe 53.

[0048] The sealing plate 51 seals the top of the cavity 3121 to ensure no gas leakage. When injecting gas, the valve 531 is opened, and the inflation end of the inflation device is connected to the inflation pipe 53. Inert gas is injected into the cavity 3121 through the inflation pipe 53. After inflation is completed, the valve 531 is closed to achieve a seal. The elastic thrust part 52 is compressed and stored by the gas pressure during the inflation process, which stores power for subsequent rapid exhaust. This gas injection structure is easy to operate, and the elastic thrust part 52 can increase the gas ejection speed, making the fire extinguishing response more timely.

[0049] It should be noted that the inert gases used in this invention include, but are not limited to, carbon dioxide.

[0050] In this embodiment, the elastic air-pushing part 52 includes a spring 521 and a push plate 522. The bottom of the sealing plate 51 is equipped with a push plate 522 located in the cavity 3121 via the spring 521, and the push plate 522 is slidably sleeved on the air injection pipe 53.

[0051] When inert gas is injected, the gas pressure pushes the push plate 522 upward, the spring 521 is compressed and stored energy, and the push plate 522 slides along the gas injection pipe 53. When the cell catches fire, causing the exhaust seal 6 to break and release pressure, the spring 521 releases its elastic force, pushing the push plate 522 downward quickly, squeezing the gas in the cavity 3121 to be discharged quickly. This structure can improve the inert gas injection speed and injection volume, expand the fire extinguishing coverage area, and enhance the thermal runaway suppression effect.

[0052] In this embodiment, the exhaust seal 6 includes an exhaust cover 61. An exhaust cover 61 is installed on the side of the protruding shell 312, which communicates with the cavity 3121 and is arranged toward the opening 21. A plurality of sealing parts 62 are detachably connected to the side of the exhaust cover 61.

[0053] The exhaust hood 61 connects the cavity 3121 and the opening 21 to form a gas flow channel. The sealing part 62 normally seals the exhaust hood 61 to ensure the airtightness of the cavity 3121.

[0054] When the temperature is high, the sealing part 62 will automatically break, and the gas will be ejected in a direction through the exhaust hood 61. The detachable sealing part 62 facilitates production assembly and airtightness testing. The multi-interval arrangement can realize multi-point synchronous exhaust and improve the uniformity of fire extinguishing.

[0055] In this embodiment, the sealing part 62 includes an exhaust shaft 621, and the side of the exhaust cover 61 is provided with a plurality of threaded holes arranged at intervals. The exhaust shaft 621 is threadedly connected to each of the plurality of threaded holes, and a sealing membrane 622 is connected to the end of the exhaust shaft 621.

[0056] The exhaust shaft 621 is threadedly connected to the exhaust cover 61, enabling detachable fixing and sealing, and facilitating the replacement of the sealing membrane 622;

[0057] The sealing membrane 622 normally seals the gas passage, ensuring that the cavity 3121 does not leak. When the temperature reaches the threshold, the sealing membrane 622 melts or ruptures, opening the gas passage, and the inert gas is discharged through the exhaust shaft 621 to extinguish the fire.

[0058] It should be noted that in actual use, the sealing film 622 can also be made of plastic.

[0059] In this embodiment, insertion holes 3111 are provided on both sides of the partition plate 311, and limit posts 101 are fixed on both sides of the bottom of the top cover body 1. The limit posts 101 on both sides of the bottom of the top cover body 1 are respectively inserted into the insertion holes 3111 on both sides of the partition plate 311.

[0060] The limiting post 101 of the top cover body 1 is inserted into the insertion hole 3111 of the partition plate 311 to achieve rapid positioning and circumferential limiting. The insertion fit can prevent the partition plate 311 from shifting relative to the top cover body 1, ensuring the integrity of the composite structure.

[0061] In this embodiment, the material of the partition plate 311 includes, but is not limited to, steel.

[0062] The steel separator 311 can remain undeformed and unmelted at high temperatures. Compared with the aluminum top cover body 1, the steel separator 311 has stronger heat insulation and structural support capabilities, which can effectively prevent the high temperature of the battery cell from being conducted to the top cover body 1. After the lower plastic 2 is melted, the steel separator 311 still maintains its complete shape, continuously maintaining the insulation distance between the top cover body 1 and the battery cell, thus ensuring battery safety.

[0063] The specific working principle of this invention is as follows:

[0064] After assembly, the top cover body 1, the partition component 3, and the lower plastic 2 form a three-layer composite structure. The pole post 4 passes through the assembly to achieve conductivity. Under normal conditions, the partition plate 311 and the top cover body 1 are positioned and fixed by the limiting post 101 and the insertion hole 3111. The protruding shell 312 and the protruding frame 313 are embedded in the lower plastic 2 to improve the overall integrity. The first high-temperature resistant tape 321 and the second high-temperature resistant tape 322 of the high-temperature resistant part 32 fully cover the bottom of the partition component 31 to achieve basic heat insulation.

[0065] When inert gas is injected, inert gas is injected into the cavity 3121 of the protruding shell 312 through the gas injection pipe 53. The valve 531 is closed and sealed. The spring 521 and the push plate 522 are compressed and stored by the gas. The sealing membrane 622 of the exhaust seal 6 seals the gas passage to ensure that the cavity 3121 is airtight.

[0066] When the battery cell experiences an abnormal short circuit and heats up, the high-temperature resistant part 32 first blocks the heat and delays the melting of the lower plastic 2. As the temperature continues to rise, the sealing film 622 ruptures due to heat, and the spring 521 releases its elastic force to push the push plate 522 downward. The inert gas in the cavity 3121 is directed to the fire source around the pole post 4 through the exhaust hood 61 and the opening 21 of the lower plastic 2, achieving rapid fire extinguishing. Even if the lower plastic 2 is completely melted, the steel partition plate 311 remains intact, continuously separating the top cover body 1 from the battery cell to avoid direct contact that could cause a secondary short circuit. The protruding frame 313 maintains positive and negative pole isolation to prevent cross-current from expanding the fault.

[0067] The overall design employs a triple mechanism of composite reinforced structure, high-temperature resistant insulation, and inert gas self-triggered fire extinguishing to suppress thermal runaway from three aspects: heat insulation, electrical insulation, and fire extinguishing, thereby improving the overall safety performance of the battery top cover.

[0068] The embodiments of the present invention have been described above, but the embodiments are not limited to the specific implementation methods described above. The specific implementation methods described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the embodiments described above, all of which are within the protection scope of the embodiments described above.

Claims

1. An integrated composite battery top cover, characterized in that, It includes a top cover body (1), a lower plastic (2), a partition assembly (3), and two pole posts (4); The separator component (3) is installed between the top cover body (1) and the lower plastic (2). The top cover body (1) has two loading holes. The two poles (4) pass through the lower plastic (2) and the separator component (3) and are installed in the two loading holes respectively. The partition assembly (3) includes a partition (31) and a high-temperature resistant part (32). The partition (31) is installed at the bottom of the top cover body (1) and forms a composite cover structure with it. The high-temperature resistant part (32) is connected to the bottom of the partition (31). The shape of the lower plastic (2) is adapted to the shape of the partition (31). The separator (31) includes a separator plate (311), the bottom of which is integrally formed with a raised frame (313) and two raised shells (312), and the raised frame (313) is located between the two raised shells (312). The raised shells (312) and the raised frame (313) both extend into the lower plastic (2).

2. The integrated composite battery top cover according to claim 1, characterized in that, The high-temperature resistant part (32) includes a first high-temperature resistant tape (321) and a second high-temperature resistant tape (322). The bottom of the raised shell (312) is attached with the first high-temperature resistant tape (321), and the bottom of the partition plate (311) and the raised frame (313) are both attached with the second high-temperature resistant tape (322).

3. The integrated composite battery top cover according to claim 2, characterized in that, The protruding shell (312) has a cavity (3121) inside. The top of the cavity (3121) is equipped with an injection assembly (5) for injecting inert gas into it. The inner walls on both sides of the lower plastic (2) are provided with openings (21) facing the pole post (4). The side of the protruding shell (312) is equipped with an exhaust seal (6) that communicates with the cavity (3121) and faces the opening (21).

4. The integrated composite battery top cover according to claim 3, characterized in that, The air injection assembly (5) includes a sealing plate (51) and an elastic air-thrusting part (52). The top of the cavity (3121) is equipped with a sealing plate (51) to seal its interior. The bottom of the sealing plate (51) is equipped with an elastic air-thrusting part (52) located inside the cavity (3121). An air injection pipe (53) passing through the elastic air-thrusting part (52) is installed on the sealing plate (51). A valve (531) is installed on the air injection pipe (53).

5. An integrated composite battery top cover according to claim 4, characterized in that, The elastic air-push part (52) includes a spring (521) and a push plate (522). The bottom of the sealing plate (51) is equipped with a push plate (522) located in the cavity (3121) by the spring (521), and the push plate (522) is slidably sleeved on the air injection pipe (53).

6. The integrated composite battery top cover according to claim 3, characterized in that, The exhaust seal (6) includes an exhaust hood (61), and the side of the protruding shell (312) is equipped with an exhaust hood (61) that communicates with the cavity (3121) and is arranged toward the opening (21). The side of the exhaust hood (61) is detachably connected with a plurality of spaced sealing parts (62).

7. An integrated composite battery top cover according to claim 6, characterized in that, The sealing part (62) includes an exhaust shaft (621). The side of the exhaust cover (61) is provided with a plurality of threaded holes arranged at intervals. The exhaust shaft (621) is threadedly connected to each of the plurality of threaded holes. A sealing membrane (622) is connected to the end of the exhaust shaft (621).

8. The integrated composite battery top cover according to claim 2, characterized in that, The partition plate (311) has insertion holes (3111) on both sides, and the bottom sides of the top cover body (1) are fixed with limit posts (101). The limit posts (101) on both sides of the bottom of the top cover body (1) are respectively inserted into the insertion holes (3111) on both sides of the partition plate (311).

9. The integrated composite battery top cover according to claim 1, characterized in that, The material of the partition plate (311) includes, but is not limited to, steel.

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