Battery monomer and battery pack
By setting weak parts on the bottom bracket and insulating film, the problem of the insulating film and the bottom bracket blocking the explosion-proof valve pressure relief hole is solved, and the rapid pressure relief and safety improvement of the battery cell are achieved.
Patent Information
- Application Number
- CN202520832414.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-29
- Publication Date
- 2025-07-01
- Estimated Expiration
- 2035-04-29
AI Technical Summary
The insulating film and bottom bracket of the existing battery cell will block the pressure relief hole of the explosion-proof valve, resulting in slow pressure relief and safety hazards.
The first and second weak parts are respectively provided on the bottom bracket and the insulating film, so that high temperature and high pressure substances can be opened from these parts, ensuring that the exhaust passage is larger than the original passage of the explosion-proof valve and avoiding blockage.
When the battery cell is thermally out of control, high-temperature and high-pressure substances can be quickly discharged through the weak parts of the bottom bracket and the insulating film, improving the safety of the battery cell.
Smart Images
Figure CN223052320U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of new energy batteries, in particular to a battery monomer and a battery pack. Background Art
[0002] With the development and application of lithium battery technology, the safety performance and stability requirements of battery cells are getting higher and higher. Among them, the insulation protection of battery cells is a major factor that determines their safety performance. The insulation protection of battery cells refers to the insulation isolation between the shell and the pole, electrode assembly, and explosion-proof valve. Among them, the insulation protection between the electrode assembly and the shell is particularly important, so an insulating film is set between the electrode assembly and the shell. However, after the insulating film is set, the airway setting between the insulating film and the explosion-proof valve will affect whether the exhaust of the explosion-proof valve is smooth.
[0003] The existing battery cell includes a shell, a bottom support plate, an electrode assembly, an insulating film and an explosion-proof valve. The insulating film is located between the bottom support plate and the electrode assembly, and the insulating film covers the electrode assembly. In order to ensure smooth flow between the electrode assembly and the explosion-proof valve so that pressure can be released in time when the battery cell thermally runs away, an exhaust channel will be reserved on the bottom support plate and the insulating film. The exhaust channel is usually formed by the gap between the bottom support plate and the shell. When the battery cell thermally runs away and releases pressure, the insulating film and the bottom support plate will be lifted up to exhaust gas, which will block the pressure relief hole on the explosion-proof valve, resulting in slow pressure relief and posing a safety hazard. Utility Model Content
[0004] The purpose of the utility model is to provide a battery cell to solve the problem in the prior art that the insulating film and the bottom support plate of the battery cell will block the pressure relief hole on the explosion-proof valve, posing a potential safety hazard; the utility model also provides a battery pack using the battery cell.
[0005] In order to achieve the above object, the utility model provides a battery cell, wherein the battery cell has a first direction and a second direction intersecting each other, and the battery cell comprises:
[0006] A shell, the shell comprising a bottom plate and a side plate fixedly connected to the bottom plate, the bottom plate and the side plate enclose a receiving cavity, the bottom plate is provided with an explosion-proof hole, and the explosion-proof hole penetrates the bottom plate along the first direction;
[0007] An explosion-proof valve, the explosion-proof valve is fixedly connected to the housing, and the explosion-proof valve cover seals the explosion-proof hole;
[0008] A bottom support plate, the bottom support plate is arranged in the accommodating cavity, and the bottom support plate is provided with a first weak portion;
[0009] An insulating film, the insulating film is arranged in the accommodating cavity, the insulating film is located on a side of the bottom supporting plate away from the explosion-proof valve, and the insulating film is provided with a second weak portion;
[0010] Along the first direction, the first weak part completely covers the explosion-proof valve, and the second weak part completely covers the explosion-proof valve.
[0011] In some embodiments, the bottom support plate is further provided with a first through hole, the first through hole penetrates the bottom support plate along the first direction, the first through hole and the explosion-proof hole are arranged opposite to each other along the first direction, the insulating film is further provided with a second through hole, the second through hole penetrates the insulating film along the first direction, and the second through hole and the explosion-proof hole are arranged opposite to each other along the first direction.
[0012] In some embodiments, along the first direction, the first through hole and the second through hole are coaxially arranged.
[0013] In some embodiments, the bottom support plate is further provided with a first air guide hole, and the insulating film is further provided with a second air guide hole. Along the second direction, the first air guide hole and the second air guide hole are arranged staggeredly, the first air guide hole and the first weak part are spaced apart, and the second air guide hole and the second weak part are spaced apart.
[0014] In some embodiments, there are a plurality of the first air guide holes and the second air guide holes respectively, and the first air guide holes and the second air guide holes are arranged in an array.
[0015] In some embodiments, the bottom support plate is provided with a first notch or a first groove, the first notch penetrates the bottom support plate along the first direction, and the first notch or the first groove forms the first weak part.
[0016] In some embodiments, the insulating film is provided with a second notch or a second groove, the second notch penetrates the insulating film along the first direction, and the second notch or the second groove forms the second weak part.
[0017] In some embodiments, each of the first notch and the second notch is one of an I-shaped, a curved shape or a rhombus shape.
[0018] In some embodiments, the bottom support plate is provided with a first toothed hole, and the first toothed hole forms the first weak part, and / or the insulating film is provided with a second toothed hole, and the second toothed hole forms the second weak part.
[0019] The present utility model further provides a battery pack, including the battery cell according to any one of the above technical solutions.
[0020] Compared with the prior art, the battery cell and battery pack of the embodiment of the present utility model have the following beneficial effects: the first weak part and the second weak part are respectively arranged on the bottom support plate and the insulating film. When the battery cell is in thermal runaway, the explosion-proof valve opens, and the high-temperature and high-pressure substances can open the bottom support plate and the insulating film respectively from the first weak part and the second weak part, avoiding the exhaust passage of the explosion-proof valve being blocked by the insulating film and the bottom support plate; since the first weak part and the second weak part completely cover the explosion-proof valve along the first direction, the exhaust passage after the first weak part and the second weak part are opened is larger than the exhaust passage after the explosion-proof valve is opened, ensuring that the exhaust gas can effectively discharge from the explosion-proof valve through the bottom support plate and the insulating film, and improving the safety of the battery cell. Description of the Drawings
[0021] Figure 1 is a schematic structural diagram of the battery cell of the present utility model;
[0022] Figure 2 is Figure 1 a cross-sectional view of the battery cell;
[0023] Figure 3 is Figure 2 an enlarged schematic structural diagram of part A of the battery cell;
[0024] Figure 4 is an exploded assembly diagram of the insulating film, bottom support plate and explosion-proof valve of the battery cell of the present utility model;
[0025] Figure 5 is Figure 4 a schematic structural diagram of the insulating film of the battery cell;
[0026] Figure 6 is Figure 4 a schematic structural diagram of the bottom support plate of the battery cell;
[0027] Figure 7 is Figure 4 a schematic structural diagram of the explosion-proof valve of the battery cell;
[0028] Figure 8 is another exploded assembly diagram of the insulating film, bottom support plate and explosion-proof valve of the battery cell of the present utility model;
[0029] Figure 9 is another schematic structural diagram of the first weak part and the second weak part of the insulating film, bottom support plate and explosion-proof valve of the battery cell of the present utility model.
[0030] In the figure, 1 is a housing, 11 is a receiving cavity, 12 is an explosion-proof hole, 121 is a linear hole wall, 122 is a curved hole wall, 13 is a bottom plate, 14 is a side plate, 2 is an explosion-proof valve, 21 is a first part, 22 is a second part, 3 is a bottom support plate, 31 is a first weak part, 311 is a first notch, 312 is a first tooth hole, 313 is a first groove, 32 is a first through hole, 33 is a first air guide hole, 4 is an insulating film, 41 is a second weak part, 411 is a second notch, 412 is a second tooth hole, 413 is a second groove, 42 is a second through hole, 43 is a second air guide hole, Z is a first direction, and Y is a second direction. Detailed implementation manners
[0031] The following combines the drawings and embodiments to further describe in detail the specific implementation manners of the present utility model. The following embodiments are used to illustrate the present utility model, but are not used to limit the scope of the present utility model.
[0032] A preferred embodiment of a battery cell of the present utility model is as Figures 1 to 9 shown. The battery cell includes a housing 1, an explosion-proof valve 2, a bottom support plate 3, and an insulating film 4. The housing 1 is an external protection structure of the battery cell, and the explosion-proof valve 2, the bottom support plate 3, and the insulating film 4 are all arranged inside the housing 1.
[0033] The battery cell has an intersecting first direction Z and a second direction Y. In this embodiment, the battery cell is square, the first direction Z is the height direction of the battery cell, the second direction Y is the width direction of the battery, and the first direction Z and the second direction Y are perpendicular to each other.
[0034] The housing 1 is provided with a receiving cavity 11 and an explosion-proof hole 12. The housing 1 includes a bottom plate 13 and a side plate 14 fixedly connected to the bottom plate 13. The bottom plate 13 and the side plate 14 enclose to form the receiving cavity 11, and the receiving cavity 11 is used for installing an electrode assembly. The explosion-proof hole 12 is arranged on the bottom plate 13. The explosion-proof hole 12 penetrates the bottom plate 13 along the first direction Z, and the explosion-proof hole 12 is communicated with the receiving cavity 11. The explosion-proof hole 12 is used for installing the explosion-proof valve 2 to discharge the high-temperature and high-pressure substances in the receiving cavity 11 through the explosion-proof valve 2 when the battery cell is out of control thermally, and timely reduce the pressure inside the battery cell. In this embodiment, the explosion-proof hole 12 is arranged at the bottom of the housing 1, and the battery cell adopts a bottom-mounted structure of the explosion-proof valve 2.
[0035] As Figure 1 shown, the explosion-proof hole 12 is a kidney-shaped hole. The explosion-proof hole 12 has a linear hole wall 121 and a curved hole wall 122 connected to the linear hole wall 121. The linear hole wall 121 extends along the second direction Y. There are two linear hole walls 121 and two curved hole walls 122. The two curved hole walls 122 are respectively located at both ends of the linear hole wall 121 along the second direction Y, and the two curved hole walls 122 are symmetrically arranged.
[0036] As Figure 7As shown, the explosion-proof valve 2 is fixedly connected to the housing 1. The explosion-proof valve 2 is arranged at the explosion-proof hole 12 of the housing 1 and seals the explosion-proof hole 12. Along the second direction Y, the explosion-proof valve 2 includes a first part 21 and a second part 22. The first part 21 corresponds to the linear hole wall 121, and the second part 22 corresponds to the curved hole wall 122. That is, the first part 21 is located between the two linear hole walls 121, and the parts of the two ends of the first part 21 surrounded by the curved hole walls 122 along the second direction Y are the second part 22.
[0037] As Figures 4 to 8 shown, the bottom support plate 3 and the insulating film 4 are both arranged in the accommodation cavity 11. The insulating film 4 is located on the side of the bottom support plate 3 away from the explosion-proof valve 2. The bottom support plate 3 is used to support the electrode assembly. The insulating film 4 is sleeved on the accommodation cavity 11. The insulating film 4 is used to cover the electrode assembly in the accommodation cavity 11. The side of the insulating film 4 away from the bottom support plate 3 is an open structure with an opening. The bottom and side parts of the insulating film 4 can insulate and isolate the electrode assembly and the housing 1, improving the safety of the battery cell. The bottom support plate 3 is also provided with a first weak part 31, and the insulating film 4 is provided with a second weak part 41. The first weak part 31 is a position with relatively low strength on the bottom support plate 3, and the second weak part 41 is a position with relatively low strength on the insulating film 4, so that high-temperature and high-pressure substances can break through the bottom support plate 3 and the insulating film 4 when the battery cell is in thermal runaway.
[0038] Along the first direction Z, the first weak part 31 completely covers the explosion-proof valve 2, and the second weak part 41 completely covers the explosion-proof valve 2. The exhaust passage after the first weak part 31 and the second weak part 41 are opened is larger than the exhaust passage after the explosion-proof valve 2 is opened, ensuring that the exhaust effectively discharges from the explosion-proof valve 2 through the bottom support plate 3 and the insulating film 4, and improving the safety of the battery cell.
[0039] The first weak part 31 and the second weak part 41 are arranged oppositely along the first direction Z. After the first weak part 31 of the bottom support plate 3 and the second weak part 41 of the insulating film 4 are opened, high-temperature and high-pressure substances can quickly pass through the first weak part 31 and the second weak part 41 along the first direction Z, improving the exhaust effect from the accommodation cavity 11 to the explosion-proof valve 2.
[0040] The battery cell is provided with the first weak part 31 and the second weak part 41 on the bottom support plate 3 and the insulating film 4 respectively. When the battery cell is in thermal runaway, the explosion-proof valve 2 is opened, and high-temperature and high-pressure substances can open the bottom support plate 3 and the insulating film 4 from the first weak part 31 and the second weak part 41 respectively, avoiding the exhaust passage of the explosion-proof valve 2 being blocked by the insulating film 4 and the bottom support plate 3, ensuring the effectiveness of the exhaust, and improving the safety of the battery cell.
[0041] In some embodiments, the bottom plate 3 is further provided with a first through hole 32, the first through hole 32 penetrates the bottom plate 3 along the first direction Z, the first through hole 32 and the explosion-proof hole 12 are arranged opposite to each other along the first direction Z, the insulating film 4 is further provided with a second through hole 42, the second through hole 42 penetrates the insulating film 4 along the first direction Z, and the second through hole 42 and the explosion-proof hole 12 are arranged opposite to each other along the first direction Z.
[0042] As Figure 5 shown in Figure 6 Figure, a first through hole 32 opposite to the explosion-proof hole 12 is arranged on the bottom plate 3, and a second through hole 42 opposite to the explosion-proof hole 12 is arranged on the insulating film 4. The first through hole 32 and the second through hole 42 can communicate the accommodation cavity 11 and the explosion-proof valve 2 to form an exhaust channel. When the first weak part 31 and the second weak part 41 are not opened and become ineffective, the first through hole 32 and the second through hole 42 play an exhaust role, improving the exhaust effect between the accommodation cavity 11 and the explosion-proof valve 2.
[0043] In some embodiments, along the first direction Z, the first through hole 32 and the second through hole 42 are coaxially arranged.
[0044] The first through hole 32 and the second through hole 42 are coaxially arranged along the first direction Z, which can reduce the distance of the exhaust channel. When exhausting, the high-temperature and high-pressure substances can be quickly discharged, improving the exhaust effect.
[0045] In some embodiments, the bottom plate 3 is further provided with a first air guide hole 33, and the insulating film 4 is further provided with a second air guide hole 43. Along the second direction Y, the first air guide hole 33 and the second air guide hole 43 are arranged staggeredly. The first air guide hole 33 and the first weak part 31 are arranged at intervals, and the second air guide hole 43 and the second weak part 41 are arranged at intervals.
[0046] As Figure 5 shown in Figure 6 Figure, the first air guide hole 33 and the second air guide hole 43 cooperate with the first through hole 32 and the second through hole 42 to jointly form an exhaust channel to ensure the exhaust effectiveness. The first air guide hole 33 on the bottom plate 3 and the second air guide hole 43 on the insulating film 4 are staggered along the second direction Y, which can prevent the electrode assembly in the accommodation cavity 11 from directly overlapping on the housing 1 through the first air guide hole 33 and the second air guide hole 43, reducing the probability of internal short circuit of the battery cell. And the first air guide hole 33 and the first weak part 31 are arranged at intervals, and the second air guide hole 43 and the second weak part 41 are arranged at intervals, reasonably utilizing the bottom space of the bottom plate 3 and the insulating film 4, so that the first air guide hole 33, the first weak part 31, the second air guide hole 43 and the second weak part 41 exist at the same time, effectively increasing the exhaust efficiency of the exhaust channel.
[0047] In some embodiments, there are multiple first air guide holes 33 and second air guide holes 43, and the first air guide holes 33 and the second air guide holes 43 are arranged in an array.
[0048] There are multiple first air guide holes 33 and second air guide holes 43, which are arranged in an array, so as to increase the gas discharge efficiency and play a role in quickly decompressing during battery thermal runaway.
[0049] In some embodiments, the bottom plate 3 is provided with a continuous first notch 311 or a first groove 313. The first notch 311 penetrates the bottom plate 3 along the first direction Z, and the first notch 311 or the first groove 313 forms a first weak part 31.
[0050] In some embodiments, the insulating film 4 is provided with a continuous second notch 411 or a second groove 413. The second notch 411 penetrates the insulating film 4 along the first direction Z, and the second notch 411 or the second groove 413 forms a second weak part 41.
[0051] As Figure 4 shown, the first notch 311 penetrating the bottom plate 3 forms a first weak part 31, and the second notch 411 penetrating the insulating film 4 forms a second weak part 41. Both the first notch 311 and the second notch 411 are continuous structures. When the battery cell is in thermal runaway, the bottom plate 3 and the insulating film 4 can be respectively flushed open along the first notch 311 and the second notch 411 by high-temperature and high-pressure substances, ensuring the effectiveness of the first weak part 31 and the second weak part 41.
[0052] As Figure 9 shown, the difference between the first groove 313 and the first notch 311 is that the first groove 313 does not penetrate the bottom plate 3 along the first direction Z, that is, the thickness dimension of the bottom plate 3 at the first groove 313 is reduced; similarly, the thickness dimension of the insulating film 4 at the second groove 413 is reduced. The first notch 311 and the first groove 313 on the bottom plate 3, and the second notch 411 and the second groove 413 on the insulating film 4 can be randomly combined, so that there are various layout structures for the first weak part 31 and the second weak part 41.
[0053] In some embodiments, both the first notch 311 and the second notch 411 are one of an I-shaped, a curved shape or a rhombus shape.
[0054] As common notch forms, the I-shaped, the curved shape and the rhombus shape have simple processing methods and good opening effects when impacted by high-temperature and high-pressure substances.
[0055] In some embodiments, the bottom plate 3 is provided with a plurality of first tooth holes 312 arranged at intervals, and the first tooth holes 312 form a first weak part 31. The insulating film 4 is provided with a plurality of second tooth holes 412 arranged at intervals, and the second tooth holes 412 form a second weak part 41.
[0056] As Figure 8As shown, the first perforation 312 and the second perforation 412 are both discontinuous structures. In this embodiment, the first perforation 312 penetrates through the bottom support plate 3 along the first direction Z, and the second perforation 412 penetrates through the insulating film 4 along the first direction Z. The first perforation 312 and the second perforation 412 can communicate the accommodation cavity 11 with the explosion-proof valve 2, and enable the first weak part 31 and the second weak part 41 to have a certain strength, so as to avoid damage to the bottom support plate 3 and the insulating film 4 during assembly.
[0057] A preferred embodiment of a battery pack of the present utility model includes battery cells. The specific structure of the battery cells is the same as that of the battery cells in any of the above embodiments, and will not be repeated here.
[0058] In summary, the embodiments of the present utility model provide a battery cell and a battery pack, in which a first weak part and a second weak part are respectively arranged on the bottom support plate and the insulating film. When the battery cell is in thermal runaway, the explosion-proof valve opens, and high-temperature and high-pressure substances can open the bottom support plate and the insulating film from the first weak part and the second weak part respectively, so as to avoid the exhaust passage of the explosion-proof valve being blocked by the insulating film and the bottom support plate; since the first weak part and the second weak part completely cover the explosion-proof valve along the first direction, the exhaust passage after the first weak part and the second weak part are opened is larger than the exhaust passage after the explosion-proof valve is opened, ensuring that the exhaust effectively passes through the explosion-proof valve through the bottom support plate and the insulating film, and improving the safety of the battery cell.
[0059] The above are only the preferred embodiments of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present utility model, several improvements and substitutions can be made, and these improvements and substitutions should also be regarded as the protection scope of the present utility model.
Claims
1. A battery cell, characterized in that: The battery cell has a first direction and a second direction intersecting each other, and the battery cell includes: A shell, the shell comprising a bottom plate and a side plate fixedly connected to the bottom plate, the bottom plate and the side plate enclose a receiving cavity, the bottom plate is provided with an explosion-proof hole, and the explosion-proof hole penetrates the bottom plate along the first direction; An explosion-proof valve, the explosion-proof valve is fixedly connected to the housing, and the explosion-proof valve cover seals the explosion-proof hole; A bottom support plate, the bottom support plate is arranged in the accommodating cavity, and the bottom support plate is provided with a first weak portion; An insulating film, the insulating film is arranged in the accommodating cavity, the insulating film is located on a side of the bottom supporting plate away from the explosion-proof valve, and the insulating film is provided with a second weak portion; Along the first direction, the first weak portion completely covers the explosion-proof valve, and the second weak portion completely covers the explosion-proof valve.
2. The battery cell according to claim 1, characterized in that: The bottom support plate is also provided with a first through hole, which penetrates the bottom support plate along the first direction, and the first through hole and the explosion-proof hole are arranged opposite to each other along the first direction. The insulating film is also provided with a second through hole, which penetrates the insulating film along the first direction, and the second through hole and the explosion-proof hole are arranged opposite to each other along the first direction.
3. The battery cell according to claim 2, characterized in that: Along the first direction, the first through hole and the second through hole are coaxially arranged.
4. The battery cell according to any one of claims 1 to 3, characterized in that: The bottom support plate is also provided with a first air guide hole, and the insulating film is also provided with a second air guide hole. Along the second direction, the first air guide hole and the second air guide hole are staggered, the first air guide hole and the first weak portion are spaced apart, and the second air guide hole and the second weak portion are spaced apart.
5. The battery cell according to claim 4, characterized in that: There are a plurality of the first air guide holes and a plurality of the second air guide holes, and the first air guide holes and the second air guide holes are arranged in an array.
6. The battery cell according to any one of claims 1 to 3, characterized in that: The bottom support plate is provided with a first cut or a first groove, the first cut runs through the bottom support plate along the first direction, and the first cut or the first groove forms the first weak portion.
7. The battery cell according to claim 6, characterized in that: The insulating film is provided with a second cut or a second groove, the second cut penetrates the insulating film along the first direction, and the second cut or the second groove forms the second weak portion.
8. The battery cell according to claim 7, characterized in that: The first cut mark and the second cut mark are both in an I-shape, a curve shape or a diamond shape.
9. The battery cell according to claim 6, characterized in that: The bottom support plate is provided with a first tooth hole, the first tooth hole forms the first weak portion, and / or the insulating film is provided with a second tooth hole, the second tooth hole forms the second weak portion.
10. A battery pack, characterized in that: A battery cell comprising the battery cell according to any one of claims 1 to 9.