Battery end cover structure and battery
By using a high-temperature resistant layer and a convex hull structure in the battery end cap structure, the problem of the battery thermal runaway pole group blocking the explosion-proof valve is solved, ensuring the discharge of high-temperature and high-pressure gas, and improving the safety of the battery.
Patent Information
- Application Number
- CN202420010965.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-02
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2034-01-02
AI Technical Summary
After the existing batteries are thermally out of control, due to the melting of the plastic insulation structure, the extreme set is easy to block or block the explosion-proof valve, resulting in the high-temperature and high-pressure gas being unable to be discharged in time, which may cause fire or explosion.
The outer surface of the insulating member is coated with a high-temperature resistant layer and the convex hull structure supports the electrode group to ensure that the gas can be discharged from the explosion-proof valve smoothly. High-temperature resistant layer materials such as ceramic coatings or fluororesin coatings are used to improve insulation and support capabilities.
Effectively prevent the pole group from blocking the explosion-proof valve, ensure that the internal gas inside the battery is discharged in time, improve the safety of the battery, and the high-temperature resistant layer is not easy to melt, enhancing the stability and safety performance of the insulating structure.
Smart Images
Figure CN222168540U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, in particular to a battery end cover structure and a battery. Background Art
[0002] In the field of battery technology, a battery generally includes a shell, an end cap disposed on the shell, a pole group disposed inside the shell, and a lower plastic structure. The lower plastic, the end plate of the pole group, the side plate of the pole group, and the bare cell insulating sheet together constitute the insulation protection structure of the pole group to prevent short circuits between the pole group and the shell or the end cap. An explosion-proof valve is provided on the cover plate. When thermal runaway occurs inside the battery, the high-temperature and high-pressure gas generated inside the battery can be discharged from the explosion-proof valve in time to ensure battery safety.
[0003] However, the existing battery insulation protection structures are all made of plastic. When the battery experiences thermal runaway, the temperature inside the battery rises rapidly, causing the bare cell insulation sheet and the lower plastic and other insulation structures to melt. In addition, the high-temperature and high-pressure gas generated inside the pole group will quickly spray toward the explosion-proof valve and drive the pole group to move. Due to the lack of support from plastic parts, the pole group can easily block or block the explosion-proof valve, making it impossible for the high-temperature and high-pressure gas inside the battery to be discharged from the explosion-proof valve in time, which can cause the battery to catch fire or even explode. It can be seen that the existing batteries cannot meet the requirements for safety performance after thermal runaway occurs. Utility Model Content
[0004] In view of this, the utility model provides a battery end cover structure and a battery to solve the problem that after thermal runaway occurs in the existing battery, the pole group moves and easily blocks the explosion-proof valve due to the melting of the plastic parts.
[0005] In order to achieve the above objectives, the following technical solutions are provided:
[0006] The battery end cover structure comprises:
[0007] A cover plate, wherein an explosion-proof valve is arranged on the cover plate;
[0008] A lower insulating member is arranged on the inner side of the cover plate facing the pole group, the lower insulating member is provided with an opening at a position corresponding to the explosion-proof valve, and the lower insulating member includes a convex bump protruding toward the pole group;
[0009] The high temperature resistant layer is coated on the outer surface of the lower insulating member, and covers the area outside the projection range of the opening, so that the gas inside the battery can be discharged from the explosion-proof valve.
[0010] Optionally, the high temperature resistant layer is coated on the outer side surface of the lower insulating member, the bottom surface of the lower insulating member, the surface of the convex hull and the inner wall of the opening.
[0011] Optionally, the number of the convex humps is at least two, and the convex humps are arranged at intervals along the length direction of the lower insulating member.
[0012] Optionally, convex bumps are provided on both sides of the opening of the lower insulating member.
[0013] Optionally, the convex bump extends to both ends of the lower insulating member along the width direction of the lower insulating member.
[0014] Optionally, a liquid injection hole is arranged on the cover plate, a through hole is opened at a position of the convex bump corresponding to the liquid injection hole, and the high temperature resistant layer covers the inner side wall of the through hole.
[0015] Optionally, the battery end cover structure further comprises a pole group end plate, which is arranged on a side of the lower insulating member facing the pole group, and a side of the pole group end plate facing the convex hump is provided with an avoidance groove to avoid the convex hump.
[0016] Optionally, the thickness of the high temperature resistant layer is 50 μm-500 μm.
[0017] Optionally, the high temperature resistant layer is a ceramic coating.
[0018] The battery comprises an electrode group, a shell and the above-mentioned battery end cover structure, wherein the cover plate is arranged on the open part of the shell, and the electrode group is arranged inside the shell.
[0019] The beneficial effects of the utility model are:
[0020] The battery end cover structure and battery provided by the utility model, by coating the outer surface of the lower insulating member with a high temperature resistant layer, reduce the efficiency of temperature transfer to the lower insulating member, so that the high temperature in the battery is not enough to melt the lower insulating member or requires a higher temperature to melt. Therefore, even if the pole group moves under the drive of the ejected gas, the convex hull can still support the pole group, so that the pole group will not block or block the explosion-proof valve, ensuring that the gas inside the battery can be discharged smoothly from the explosion-proof valve. When the battery is thermally runaway, even if the temperature inside the battery is too high and causes the lower insulating member to melt, the high temperature resistant layer will not melt due to its high temperature resistance. Since the high temperature resistant layer is coated on the outer surface of the lower insulating member, the outer contour of the high temperature resistant layer is consistent with the outer contour of the lower insulating member. The high temperature resistant layer at the convex hull position can still support the pole group to prevent the pole group from blocking or blocking the explosion-proof valve, thereby greatly improving the safety of the battery. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0022] Figure 1A schematic diagram of the structure of the cover plate and the lower insulating member provided by the utility model;
[0023] Figure 2 This is a schematic diagram of the battery end cover structure provided by the utility model.
[0024] Description of reference numerals:
[0025] 1. Cover plate; 11. Explosion-proof valve;
[0026] 2. lower insulating member; 21. opening; 22. convex bump; 221. through hole;
[0027] 3. Pole group end plate; 31. Avoidance groove. DETAILED DESCRIPTION
[0028] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.
[0029] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0030] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0031] In the description of the present invention, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.
[0032] In the field of battery technology, since the existing battery insulation protection structures are all made of plastic, when the battery has thermal runaway, the internal temperature of the battery rises rapidly, causing the bare cell insulation sheet and the lower plastic and other insulation structures to melt. In addition, the high-temperature and high-pressure gas generated inside the pole group will quickly spray toward the explosion-proof valve and drive the pole group to move. Due to the lack of support from plastic parts, the pole group can easily block or block the explosion-proof valve, so that the high-temperature and high-pressure gas inside the battery cannot be discharged from the explosion-proof valve in time, which can cause the battery to catch fire or even explode. It can be seen that the existing batteries cannot meet the requirements for safety performance after thermal runaway occurs. Therefore, this embodiment provides a battery end cover structure to solve the above problems.
[0033] like Figure 1 As shown, this embodiment provides a battery end cover structure, which includes a cover plate 1, a lower insulating member 2 and a high temperature resistant layer. An explosion-proof valve 11 is provided on the cover plate 1, and the lower insulating member 2 is provided on the inner side of the cover plate 1 facing the pole group. The lower insulating member 2 is provided with an opening 21 at a position corresponding to the explosion-proof valve 11, and the lower insulating member 2 includes a convex bulge 22 protruding toward the pole group, and the convex bulge 22 is used to support the pole group. The high temperature resistant layer is coated on the outer surface of the lower insulating member 2, and the high temperature resistant layer covers the area outside the projection range of the opening 21, so that the gas inside the battery can be discharged from the explosion-proof valve 11.
[0034] When the battery thermally runs away, the high-temperature and high-pressure gas generated inside the pole group will be quickly ejected toward the explosion-proof valve 11, and drive the pole group to move. The battery cover structure of this embodiment covers the outer surface of the lower insulating member 2 with a high-temperature resistant layer, reduces the efficiency of temperature transfer to the lower insulating member 2, and makes the high temperature in the battery insufficient to melt the lower insulating member 2. Therefore, even if the pole group moves under the drive of the ejected gas, the convex hull 22 can still support the pole group, so that the pole group will not block or block the explosion-proof valve 11, ensuring that the gas inside the battery can be discharged smoothly from the explosion-proof valve 11. When the battery thermally runs away, the internal temperature of the battery is too high to cause the lower insulating member 2 to melt, but the high-temperature resistant layer will not melt due to its high-temperature resistant characteristics. Since the high-temperature resistant layer is coated on the outer surface of the lower insulating member 2, the outer contour of the high-temperature resistant layer is consistent with the outer contour of the lower insulating member 2. The high-temperature resistant layer at the position of the convex hull 22 can still support the pole group, preventing the pole group from blocking or blocking the explosion-proof valve 11, thereby greatly improving the safety of the battery.
[0035] The explosion-proof valve 11 is a battery component known in the art, and any type of explosion-proof valve 11 is applicable to this embodiment, and this embodiment does not introduce and limit the specific structure of the explosion-proof valve 11. In this embodiment, the lower insulating member 2 is specifically a lower plastic.
[0036] Furthermore, in order to ensure that the lower insulating member 2 plays an insulating role between the pole group and the cover plate 1, the outer surface of the lower insulating member 2 facing the cover plate 1 is not covered with a high temperature resistant layer. The high temperature resistant layer is coated on the outer side surface of the lower insulating member 2, the bottom surface of the lower insulating member 2, the surface of the convex 22, and the inner wall of the opening 21. That is, the high temperature resistant layer is coated on the outer surface of the lower insulating member 2 facing the pole group to protect the lower insulating member 2, reduce the heat spread of the lower insulating member 2, and make the lower insulating member 2 less likely to melt or require a higher temperature to melt. This solution not only ensures the insulating role of the lower insulating member 2, but also ensures that the lower insulating member 2 is less likely to melt.
[0037] In some embodiments, the high temperature resistant layer is only coated on the outer side of the lower insulating member 2, and the high temperature resistant layer is annular. After the lower insulating member 2 melts, the annular high temperature resistant layer does not melt due to its high temperature resistance, and the remaining annular high temperature resistant layer is between the cover plate 1 and the electrode group. Therefore, the annular high temperature resistant layer can still support the electrode group to prevent the electrode group from blocking or clogging the explosion-proof valve 11, and the annular high temperature resistant layer forms a cavity between the electrode group and the cover plate 1, so that the high temperature and high pressure gas in the battery can be discharged from the explosion-proof valve 11 through the cavity.
[0038] In some embodiments, the high temperature resistant layer is only coated on the outer surface of the convex hull 22, and the contour of the high temperature resistant layer is consistent with the contour of the convex hull 22, that is, the high temperature resistant layer is also in the shape of the convex hull 22. When the battery has thermal runaway and the lower insulating member 2 melts, the high temperature resistant layer does not melt due to its high temperature resistance. The high temperature resistant layer in the shape of the convex hull 22 is between the cover plate 1 and the pole group. Therefore, the high temperature resistant layer can still support the pole group, so that there is a gap between the pole group and the explosion-proof valve 11, thereby preventing the pole group from blocking or blocking the explosion-proof valve 11. In this way, the high temperature and high pressure gas inside the battery is discharged from the explosion-proof valve 11 through the gap, thereby ensuring the safety of the battery.
[0039] Furthermore, there are at least two convex bumps 22, which are arranged at intervals along the length direction of the lower insulating member 2. This solution makes the two or more convex bumps 22 support the electrode group more stably, prevents the electrode group from tilting to the side and blocking or blocking the explosion-proof valve 11, and further improves the safety of the battery.
[0040] Specifically, convex bumps 22 are provided on both sides of the opening 21 on the lower insulating member 2. That is, the explosion-proof valve 11 has convex bumps 22 on both sides, and the convex bumps 22 on both sides of the explosion-proof valve 11 jointly support the electrode group, so that there is a gap between the electrode group and the explosion-proof valve 11. Therefore, no matter how the electrode group moves in the battery shell, the electrode group cannot cover or block the explosion-proof valve 11, and the high-temperature and high-pressure gas inside the battery can be discharged from the explosion-proof valve 11 through the gap.
[0041] Furthermore, the convex hump 22 extends to both ends of the lower insulating member 2 along the width direction of the lower insulating member 2. The convex hump 22 of this embodiment is a rectangular parallelepiped, thereby making the contact area between the convex hump 22 and the pole group larger. This solution further improves the stability of the support of the pole group by the convex hump 22.
[0042] In some embodiments, the convex hull 22 may also be spherical or triangular.
[0043] Furthermore, in order to facilitate the liquid injection operation of the battery, a liquid injection hole is provided on the cover plate 1, and a through hole 221 is provided at the position of the convex bump 22 corresponding to the liquid injection hole, and the high temperature resistant layer covers the inner wall of the through hole 221 to prevent the inner wall of the through hole 221 from directly contacting the high temperature gas inside the battery, so as to reduce the heat transfer efficiency of the lower insulating member 2. In addition, the through hole 221 is connected with the opening 21. When the battery is in thermal runaway and the lower insulating member 2 melts, the liquid, electrolyte and high temperature and high pressure gas after the lower insulating member 2 and other insulating structures inside the battery melt can be discharged from the through hole 221 to the explosion-proof valve 11 through the opening 21, so as to prevent the rapid accumulation of gas and liquid inside the battery, so that the gas and liquid inside the battery can be discharged from the explosion-proof valve 11 more timely, and the safety of the battery is further ensured.
[0044] Furthermore, if Figure 2 As shown, the battery end cover structure of this embodiment also includes a pole group end plate 3, which is arranged on the side of the lower insulating member 2 facing the pole group, and a side of the pole group end plate 3 facing the convex hump 22 is provided with an avoidance groove 31 to avoid the convex hump 22. The pole group end plate 3 is also connected and installed with the end of the pole group, and the avoidance groove 31 of the pole group end plate 3 cooperates with the convex hump 22 to limit the position of the pole group, reduce the amplitude of movement or swing of the pole group caused by thermal runaway, and also ensure that the pole group is not easy to shake during normal use of the battery, making the battery safer.
[0045] Furthermore, in order to ensure that the high temperature resistant layer can protect the lower insulating member 2 and prevent the lower insulating member 2 from melting, and that the high temperature resistant layer has sufficient strength to support the pole group after the lower insulating member 2 melts, the thickness of the high temperature resistant layer in this embodiment is 50 μm-500 μm.
[0046] Furthermore, the high temperature resistant layer is a ceramic coating. The ceramic coating has high heat resistance and hardness, can effectively protect the lower insulating member 2, and makes the lower insulating member 2 not easy to melt, and the ceramic coating has sufficient strength to support the pole group. In addition, the ceramic material is an extremely excellent insulating material, which can play an insulating role between the pole group and the cover plate 1.
[0047] Optionally, the ceramic coating of this embodiment is sprayed on the surface of the lower insulating member 2 and cured by a UV light curing machine, and the curing temperature is preferably 40°C-150°C to make the surface of the lower insulating member 2 sprayed with ceramic coating more efficient.
[0048] In some embodiments, the material of the high temperature resistant layer is fluororesin coating, heterocyclic polymer coating or organosilicon high temperature resistant coating.
[0049] In some embodiments, the ceramic coating is sprayed onto the surface of the lower insulating part 2 by an electrostatic spray machine. Under the action of static electricity, the powder of the ceramic coating will be evenly adsorbed on the surface of the workpiece to form a coating. The powder coating is baked at high temperature to level and solidify to form a final ceramic coating.
[0050] This embodiment further provides a battery, which includes a pole group, a shell and the above-mentioned battery end cover structure, wherein the cover plate 1 is arranged on the open portion of the shell, and the pole group is arranged inside the shell.
[0051] Note that in the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.
[0052] The above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.
Claims
1. A battery end cover structure, characterized in that: include: A cover plate, wherein an explosion-proof valve is arranged on the cover plate; A lower insulating member is arranged on the inner side surface of the cover plate facing the pole group, the lower insulating member is provided with an opening at a position corresponding to the explosion-proof valve, and the lower insulating member includes a convex bump protruding toward the pole group; A high temperature resistant layer is coated on the outer surface of the lower insulating member, and the high temperature resistant layer covers the area outside the projection range of the opening, so that the gas inside the battery can be discharged from the explosion-proof valve.
2. The battery end cover structure according to claim 1, characterized in that: The high temperature resistant layer is coated on the outer side surface of the lower insulating member, the bottom surface of the lower insulating member, the surface of the convex bulge and the inner wall of the opening.
3. The battery end cover structure according to claim 1, characterized in that: The number of the convex humps is at least two, and the convex humps are arranged at intervals along the length direction of the lower insulating member.
4. The battery end cover structure according to claim 3, characterized in that: The lower insulating member is provided with convex bumps at both sides of the opening.
5. The battery end cover structure according to any one of claims 1 to 4, characterized in that: The convex bumps extend to both ends of the lower insulating member along a width direction of the lower insulating member.
6. The battery end cover structure according to any one of claims 1 to 4, characterized in that: The cover plate is provided with a liquid injection hole, the convex bump is provided with a through hole at a position corresponding to the liquid injection hole, and the high temperature resistant layer covers the inner side wall of the through hole.
7. The battery end cover structure according to any one of claims 1 to 4, characterized in that: It also includes a pole group end plate, which is arranged on a side of the lower insulating member facing the pole group, and a side of the pole group end plate facing the convex hump is provided with an avoidance groove to avoid the convex hump.
8. The battery end cover structure according to any one of claims 1 to 4, characterized in that: The thickness of the high temperature resistant layer is 50 μm-500 μm.
9. The battery end cover structure according to any one of claims 1 to 4, characterized in that: The high temperature resistant layer is a ceramic coating.
10. A battery, characterized in that It comprises a pole group, a shell and a battery end cover structure as claimed in any one of claims 1 to 9, wherein the cover plate is arranged on the open part of the shell, and the pole group is arranged inside the shell.