Battery cell protection structure and battery

Abstract

The utility model relates to the technical field of lithium batteries, and discloses a battery cell protection structure and a battery, the battery cell protection structure comprises a shell, the inner side peripheral wall of the shell is enclosed to form a containing cavity, and the containing cavity is suitable for containing a battery cell pole group; the side, in the first direction, of the shell is a target side wall, and the side, away from the containing cavity in the first direction, of the target side wall is suitable for being provided with an anti-explosion valve. The lining protection plate is attached to the target side wall, the lining protection plate is arranged on the side, facing the battery cell pole group in the first direction, of the target side wall, and the lining protection plate is suitable for preventing the battery cell pole group from scratching and / or extruding the anti-explosion valve. According to the battery cell protection structure provided by the utility model, the explosion-proof valve is prevented from being scratched and extruded by the battery cell pole group and / or the battery cell side plate in the process of assembling the pole group into the shell or when the pole group and / or the side plate in the shell move, so that the exhaust passage is better protected, and the safety performance of the battery cell is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, and in particular to a battery core protection structure and a battery. Background Art

[0002] As lithium-ion battery technology matures, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields, and the requirements for the performance and safety of lithium-ion batteries are increasing. The lithium battery housing and explosion-proof valve are core assembly components related to the safety of the battery cell, and their structural design is crucial to the safety of the battery cell.

[0003] The existing battery cell shell is formed by stretching and welding, and the explosion-proof valve hole is formed by machining and stamping, and then the explosion-proof valve is welded to the outer peripheral wall of the battery cell shell to weld the explosion-proof valve to the explosion-proof valve hole. When the battery cell pole group is assembled into the shell or the battery cell pole group and the side plate in the battery cell shell move, it is easy to scratch or squeeze the explosion-proof valve on the shell, causing the risk of battery safety failure. Utility Model Content

[0004] In view of this, the utility model provides a battery cell protection structure and a battery to solve the problem that the existing battery cell shell is easily scratched or squeezed against the explosion-proof valve on the shell when the battery cell pole assembly is installed into the shell or the battery cell pole and side plate in the battery cell shell move.

[0005] In a first aspect, the utility model provides a battery cell protection structure, comprising:

[0006] A shell, wherein the inner peripheral wall of the shell encloses a receiving cavity, and the receiving cavity is suitable for receiving the battery cell electrode group;

[0007] One side of the shell along the first direction is a target side wall, and a side of the target side wall along the first direction away from the accommodating cavity is suitable for arranging an explosion-proof valve;

[0008] The inner lining protection plate is arranged in close contact with the target side wall. The inner lining protection plate is arranged on a side of the target side wall along the first direction toward the battery cell pole group. The inner lining protection plate is suitable for preventing the battery cell pole group from scratching and / or squeezing the explosion-proof valve.

[0009] The battery cell protection structure provided by the utility model arranges an inner lining protection plate in the accommodating cavity of the shell, and attaches the inner lining protection plate to the side of the target side wall along the first direction toward the battery cell pole group, so that the battery cell pole group and the battery cell side plate are isolated from the explosion-proof valve by the inner lining protection plate, avoiding the battery cell pole group and / or battery cell side plate from scratching or squeezing the explosion-proof valve when the pole group is assembled into the shell or the pole group and / or side plate inside the shell moves, which is conducive to better protecting the exhaust channel and improving the safety performance of the battery cell.

[0010] In an optional embodiment, a mounting opening is provided on the target side wall, and the mounting opening is suitable for arranging an explosion-proof valve;

[0011] A ventilation grille is formed on the inner lining protection plate, and the ventilation grille and the installation opening are arranged one by one along the first direction. The ventilation grille is suitable for connecting the accommodating cavity with the installation opening.

[0012] By arranging a ventilation grille on the inner lining protective plate, the accommodating cavity is connected with the mounting port through the ventilation grille. When thermal runaway occurs in the battery cell, exhaust and heat dissipation can be carried out to the mounting port through the ventilation grille, thereby ensuring that the explosion-proof valve can be detonated normally.

[0013] In an optional implementation, the flow area of ​​each ventilation grille is F, and F satisfies F≥0.4·S, wherein S is the size of the detonation area of ​​a single explosion-proof valve.

[0014] Through such an arrangement, sufficient ventilation area of ​​the lining protection plate can be ensured, eliminating the potential risk of the explosion-proof valve failing to detonate normally.

[0015] In an optional embodiment, each ventilation grille includes a plurality of first through holes, the first through holes are formed by opening the lining protective plate along the first direction, the plurality of first through holes are arranged on the lining protective plate along the second direction and / or the third direction at intervals, and one end of the first through hole along the first direction is suitable for being connected to the accommodating cavity, and the other end is suitable for being connected to the installation port.

[0016] A plurality of first through holes are arranged in pairs along the second direction and / or the third direction to form a ventilation grille on the inner lining protective plate. On the one hand, the battery cell pole group and the battery cell side plate can be isolated from the explosion-proof valve to prevent the battery cell pole group and / or the battery cell side plate from scratching or squeezing the explosion-proof valve; on the other hand, the accommodating cavity can be connected with the installation port to ensure that the explosion-proof valve can be normally detonated when thermal runaway occurs in the battery cell; and on the third hand, the structural strength of the entire inner lining protective plate can be ensured.

[0017] In an optional implementation, the flow area size F of each ventilation grille also satisfies F≤2·S.

[0018] Through such an arrangement, on the one hand, sufficient ventilation area of ​​the lining protective plate is guaranteed to ensure that the explosion-proof valve can be normally detonated when thermal runaway occurs in the battery cell; on the other hand, the structural strength of the lining protective plate is guaranteed, and the energy density of the battery cell group is maximized.

[0019] In an optional embodiment, a cell side plate is provided on the side of the cell pole group close to the target side wall along the first direction, the cell side plate is in contact with the outer side wall of the cell pole group, the cell side plate is suitable for entering the accommodating cavity together with the cell pole group, and the side of the cell side plate away from the cell pole group along the first direction is at least partially in contact with the lining protective plate.

[0020] The side of the battery cell side plate away from the battery cell pole group along the first direction is at least partially in contact with the liner protection plate, thereby preventing the battery cell pole group from being offset in the accommodating cavity.

[0021] In an optional embodiment, an exhaust gap is formed between the battery cell side plate and the liner protection plate along the first direction.

[0022] One side of the exhaust gap along the first direction is connected to the first through hole of the ventilation grille, and the other side is connected to the accommodating cavity, thereby forming an exhaust channel between the battery cell pole group and the explosion-proof valve, which is conducive to forming sufficient airway space inside the battery cell to ensure the safety of the battery cell.

[0023] In an optional embodiment, a plurality of protrusions are provided on one side of the battery cell side plate away from the battery cell pole group along the first direction, and the protrusions are suitable for abutting against the lining protection plate to form an exhaust gap between the battery cell side plate and the lining protection plate.

[0024] The protrusions abut against the inner lining protection plate to support the side plates of the battery cells, so that an exhaust gap is formed between the side plates of the battery cells and the inner lining protection plate, thereby ensuring sufficient airway space and improving the safety of the battery cells.

[0025] In an optional implementation, a plurality of second through holes are formed on the side plate of the battery cell, and the second through holes are connected to the exhaust gap.

[0026] When thermal runaway occurs in the battery cell, the thermal runaway gas first enters the exhaust gap through the second through hole, and then reaches the installation port from the exhaust gap through the first through hole, thereby triggering the explosion-proof valve to detonate normally.

[0027] In a second aspect, the utility model further provides a battery, comprising: a battery body, and the battery cell protection structure as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] 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.

[0029] Figure 1 A schematic diagram of the working principle of a battery cell protection structure according to an embodiment of the utility model;

[0030] Figure 2 This is a schematic diagram of an explosion structure of a battery core protection structure according to an embodiment of the utility model;

[0031] Figure 3 for Figure 2 A local enlarged schematic diagram of the middle A;

[0032] Figure 4 for Figure 3 Schematic diagram of the top view of the explosion-proof valve;

[0033] Figure 5 This is a schematic diagram of the assembly structure of a shell and an explosion-proof valve of a battery core protection structure according to an embodiment of the utility model;

[0034] Figure 6 This is a schematic diagram of a top view of a battery cell protection structure according to an embodiment of the utility model;

[0035] Figure 7 for Figure 6 Schematic diagram of the cross-sectional structure of the middle BB section;

[0036] Figure 8 for Figure 7 A partial enlarged schematic diagram of point D in the middle;

[0037] Fig. 9 for Figure 6 Schematic diagram of the cross-sectional structure of the CC section;

[0038] Fig.10 for Fig. 9 A partial enlarged schematic diagram of point E in the middle.

[0039] Description of reference numerals:

[0040] 10. Shell; 101. Accommodating cavity; 102. Insertion port; 11. Target side wall; 111. Installation port;

[0041] 20. Battery cell group;

[0042] 30. Explosion-proof valve; 31. Welding area; 32. Detonation area;

[0043] 40. Liner protection plate; 41. Ventilation grille; 411. First through hole;

[0044] 50. Cell side plate; 501. Exhaust gap; 51. Protrusion; 52. Second through hole. DETAILED DESCRIPTION

[0045] 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.

[0046] The battery cell shell in the related technology is made of aluminum shell formed by stretching and welding, and the interior of the shell is only a smooth metal surface without a protective structure; the explosion-proof valve hole on the shell is machined and stamped, and then the explosion-proof valve is welded to the outer wall of the shell, and there is a through hole under the explosion-proof valve, and there is no protective structure inside the shell; during the process of assembling the pole group into the shell or when the pole group and / or side plate inside the shell moves, the pole group and / or side plate are easy to scratch and squeeze the explosion-proof valve on the side of the shell, causing the risk of battery cell safety failure.

[0047] Combine the following Figures 1 to 10 , describing an embodiment of the utility model.

[0048] According to an embodiment of the present utility model, on the one hand, a battery cell protection structure is provided, comprising:

[0049] The housing 10, the inner peripheral wall of the housing 10 encloses a receiving cavity 101, and the receiving cavity 101 is suitable for receiving the battery cell electrode group 20;

[0050] One side of the housing 10 along the first direction is a target side wall 11, and a side of the target side wall 11 along the first direction away from the accommodating chamber 101 is suitable for arranging an explosion-proof valve 30;

[0051] The inner lining protection plate 40 is arranged in close contact with the target side wall 11 . The inner lining protection plate 40 is arranged on a side of the target side wall 11 along the first direction toward the battery cell pole group 20 . The inner lining protection plate 40 is suitable for preventing the battery cell pole group 20 from scratching and / or squeezing the explosion-proof valve 30 .

[0052] Furthermore, the liner protective plate 40 is bonded to the side of the target side wall 11 along the first direction toward the battery cell pole group 20, so that the liner protective plate 40 is strongly and firmly attached to the target side wall 11, thereby preventing the liner protective plate 40 from being separated from the target side wall 11 during the pole group shelling process.

[0053] For further information, see Figure 2 As shown, an insertion opening 102 is provided on at least one side of the housing 10 along the second direction; during the assembly process, the battery cell electrode group 20 enters the accommodating cavity 101 through the insertion opening 102 .

[0054] Furthermore, the inner lining protection plate 40 is made of an insulating material, and the inner lining protection plate 40 can be made of a plastic material or a resin material.

[0055] The battery cell protection structure provided in the present embodiment arranges an inner lining protection plate 40 in the accommodating cavity 101 of the shell 10, and attaches the inner lining protection plate 40 to the side of the target side wall 11 along the first direction toward the battery cell pole group 20, so that the battery cell pole group 20 and the battery cell side plate 50 are isolated from the explosion-proof valve 30 by the inner lining protection plate 40, thereby preventing the battery cell pole group 20 and / or the battery cell side plate 50 from scratching or squeezing the explosion-proof valve 30 when the pole group is assembled into the shell or when the pole group and / or the side plate inside the shell moves, which is beneficial to better protect the exhaust channel and improve the safety performance of the battery cell.

[0056] In one embodiment, see Figure 2 and Figure 3 As shown, a mounting opening 111 is provided on the target side wall 11, and the mounting opening 111 is suitable for setting the explosion-proof valve 30; a ventilation grille 41 is provided on the lining protection plate 40, and the ventilation grille 41 and the mounting opening 111 are arranged one by one along the first direction; by arranging the ventilation grille 41 on the lining protection plate 40, the accommodating cavity 101 is connected with the mounting opening 111 through the ventilation grille 41, so that when thermal runaway occurs in the battery cell, exhaust and heat can be discharged to the mounting opening 111 through the ventilation grille 41, thereby ensuring that the explosion-proof valve 30 can be detonated normally.

[0057] In one embodiment, the flow area of ​​each ventilation grille 41 is F, and F satisfies F≥0.4·S, where S is the size of the detonation area of ​​a single explosion-proof valve 30 .

[0058] Please note that, see Figure 4 As shown, each explosion-proof valve 30 includes a welding area 31 and an initiation area 32. The thickness of the welding area 31 is greater than the thickness of the initiation area 32. The welding area 31 is suitable for welding with the target side wall 11. The initiation area 32 is as shown in FIG. Figure 4 As shown in the shaded part in FIG, the detonation area 32 is suitable for being opened by the gas pressure inside the battery cell when the battery cell undergoes thermal runaway; the size S of the detonation area of ​​a single explosion-proof valve 30 refers to Figure 4 The shaded portion in the figure shows the size of the detonation area 32. If the flow area of ​​each ventilation grille 41 is too small, there is a potential risk that the explosion-proof valve 30 cannot be detonated normally due to insufficient ventilation area. Therefore, the flow area size F of each ventilation grille 41 must satisfy F≥0.4·S, where S is the size of the detonation area of ​​a single explosion-proof valve 30, to ensure sufficient ventilation area of ​​the lining protection plate 40 and eliminate the potential risk that the explosion-proof valve 30 cannot be detonated normally.

[0059] In one embodiment, see Figure 3As shown, each ventilation grille 41 includes a plurality of first through holes 411, and the first through holes 411 are formed by the lining protection plate 40 opening along the first direction. The plurality of first through holes 411 are evenly spaced along the second direction and / or the third direction on the lining protection plate 40, and one end of the first through hole 411 along the first direction is suitable for being connected to the accommodating cavity 101, and the other end is suitable for being connected to the installation port 111.

[0060] It should be noted that the cross-sectional shape of the first through hole 411 can be circular or square, and can be adjusted according to actual production conditions. Figure 3 The situation shown in ; the distance between each two adjacent first through holes 411 along the second direction and / or the third direction can be adjusted according to actual design requirements. A plurality of first through holes 411 are arranged in pairs along the second direction and / or the third direction, so as to form a ventilation grille 41 on the inner lining protection plate 40. On the one hand, the battery cell pole group 20 and the battery cell side plate 50 can be isolated from the explosion-proof valve 30, thereby preventing the battery cell pole group 20 and / or the battery cell side plate 50 from scratching and squeezing the explosion-proof valve 30. On the other hand, the accommodating cavity 101 can be connected with the installation port 111, thereby ensuring that the explosion-proof valve 30 can be normally detonated when thermal runaway occurs in the battery cell, and on the other hand, the structural strength of the entire inner lining protection plate 40 can be ensured.

[0061] In one embodiment, the flow area size F of each ventilation grille 41 also satisfies F≤2·S.

[0062] It should be noted that, firstly, the inner lining protective plate 40 needs to have a certain structural strength, therefore, the inner lining protective plate 40 needs to have a certain thickness; secondly, when the material and thickness of the inner lining protective plate 40 are certain, the larger the flow area of ​​the ventilation grille 41, the smaller the structural strength of the inner lining protective plate 40; thirdly, since the accommodation space of the accommodation cavity 101 is limited, the larger the thickness of the inner lining protective plate 40, the smaller the energy density of the battery cell, therefore, under the premise of ensuring the structural strength of the inner lining protective plate 40, the thinner the thickness of the inner lining protective plate 40, the better. In summary, the flow area size F of each ventilation grille 41 must also satisfy F≤2·S, on the one hand to ensure sufficient ventilation area of ​​the inner lining protective plate 40, to ensure that the explosion-proof valve 30 can be normally detonated when thermal runaway occurs in the battery cell, on the other hand to ensure the structural strength of the inner lining protective plate 40, and on the other hand to maximize the energy density of the battery cell.

[0063] In one embodiment, please combine Figure 1 and Figure 2As shown, a cell side plate 50 is provided on the side of the cell pole group 20 close to the target side wall 11 along the first direction, and the cell side plate 50 is in contact with the outer wall of the cell pole group 20; by attaching the cell side plate 50 to the outer wall of the cell pole group 20, the cell side plate 50 and the cell pole group 20 enter the accommodating cavity 101 together, and the side of the cell side plate 50 away from the cell pole group 20 along the first direction is at least partially in contact with the lining protection plate 40, thereby avoiding the cell pole group 20 from being offset in the accommodating cavity 101.

[0064] In one embodiment, please combine Figure 8 and Fig.10 As shown, an exhaust gap 501 is formed between the battery cell side plate 50 and the lining protection plate 40 along the first direction. One side of the exhaust gap 501 along the first direction is connected with the first through hole 411 of the ventilation grille 41, and the other side is suitable for being connected with the accommodating cavity 101, thereby forming an exhaust channel between the battery cell pole group 20 and the explosion-proof valve 30, which is conducive to forming sufficient airway space inside the battery cell to ensure the safety of the battery cell.

[0065] In one embodiment, see Fig.10 As shown, a plurality of protrusions 51 are provided on one side of the battery cell side plate 50 away from the battery cell pole group 20 along the first direction, and the protrusions 51 are abutted against the lining protection plate 40 to support the battery cell side plate 50, so that an exhaust gap 501 is formed between the battery cell side plate 50 and the lining protection plate 40 to ensure sufficient airway space and improve the safety of the battery cell.

[0066] In one embodiment, see Fig.10 As shown, a plurality of second through holes 52 are provided on the battery cell side plate 50, and the second through holes 52 are connected to the exhaust gap 501; when thermal runaway occurs in the battery cell, the thermal runaway gas first enters the exhaust gap 501 through the second through holes 52, and then reaches the installation port 111 from the exhaust gap 501 through the first through holes 411, thereby triggering the explosion-proof valve 30 to detonate normally.

[0067] According to an embodiment of the present utility model, on the other hand, a battery is provided, including: a battery body, and the battery cell protection structure as described above.

[0068] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery cell protection structure, characterized in that: include: A shell, wherein the inner peripheral wall of the shell encloses a receiving cavity, and the receiving cavity is suitable for receiving the battery cell electrode group; One side of the shell along the first direction is a target side wall, and a side of the target side wall along the first direction away from the accommodating cavity is suitable for arranging an explosion-proof valve; An inner lining protective plate is arranged in close contact with the target side wall, and the inner lining protective plate is arranged on a side of the target side wall along a first direction toward the battery cell pole group, and the inner lining protective plate is suitable for preventing the battery cell pole group from scratching and / or squeezing the explosion-proof valve.

2. The battery cell protection structure according to claim 1, characterized in that: The target side wall is provided with an installation opening, and the installation opening is suitable for installing the explosion-proof valve; A ventilation grille is formed on the inner lining protection plate, and the ventilation grille and the installation opening are arranged in a one-to-one correspondence along the first direction. The ventilation grille is suitable for connecting the accommodating cavity with the installation opening.

3. The battery cell protection structure according to claim 2, characterized in that: The flow area of ​​each of the ventilation grilles is F, and F satisfies F≥0.4·S, wherein S is the size of the detonation area of ​​a single explosion-proof valve.

4. The battery cell protection structure according to claim 2, characterized in that: Each of the ventilation grilles includes a plurality of first through holes, which are formed by the inner lining protective plate opening along a first direction, and the plurality of first through holes are arranged on the inner lining protective plate at intervals along a second direction and / or a third direction, and one end of the first through hole along the first direction is suitable for being connected to the accommodating cavity, and the other end is suitable for being connected to the mounting port.

5. The battery cell protection structure according to claim 3, characterized in that: The flow area size F of each ventilation grille also satisfies F≤2·S.

6. The battery cell protection structure according to any one of claims 1 to 5, characterized in that: A cell side plate is provided on the side of the cell pole group close to the target side wall along the first direction, the cell side plate is in contact with the outer side wall of the cell pole group, the cell side plate is suitable for entering the accommodating cavity together with the cell pole group, and the side of the cell side plate away from the cell pole group along the first direction at least partially abuts against the lining protective plate.

7. The battery cell protection structure according to claim 6, characterized in that: An exhaust gap is formed between the battery cell side plate and the liner protection plate along a first direction.

8. The battery cell protection structure according to claim 7, characterized in that: A plurality of protrusions are provided on a side of the cell side plate away from the cell pole group along the first direction, and the protrusions are suitable for abutting against the liner protection plate to form the exhaust gap between the cell side plate and the liner protection plate.

9. The battery cell protection structure according to claim 7, characterized in that: A plurality of second through holes are formed on the battery core side plate, and the second through holes are connected to the exhaust gap.

10. A battery, characterized in that: include: A battery body, and a battery cell protection structure as described in any one of claims 1 to 9.

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