Battery structure and electric device

Abstract

The utility model relates to the technical field of batteries, and discloses a battery structure and an electric device, and the battery structure comprises a shell, a battery cover and a battery cover, the cover plate covers the opening of the shell, and the cover plate and the shell jointly define a containing cavity; the cover plate is provided with an anti-explosion valve; the pole group is arranged in the accommodating cavity; the end plate is arranged on the side, close to the cover plate, of the pole group, the direction perpendicular to the plane where the cover plate is located is defined as the first direction, and a supporting plate body is at least formed in the area, overlapped with the projection of the anti-explosion valve, of the end plate in the first direction; a thinning belt is formed on the supporting plate body, the thickness of at least part of the area of the thinning belt is smaller than that of the supporting plate body, and when the end plate is in a heated state higher than the melting point, the thinning belt is melted before the area of the supporting plate body. According to the battery structure provided by the utility model, when thermal runaway occurs, the thinning belt is quickly melted, so that the interior of the area enclosed by the thinning belt falls off, the exhaust space is enlarged, and enough exhaust area is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and particularly relates to a battery structure and an electric device. Background Art

[0002] A battery cell usually includes a housing, a pole group disposed in the housing, and a cover plate covering an opening of the housing. Between the cover plate and the pole group, by providing a support member, the pole group can be supported and fixed to ensure the support strength at the support position.

[0003] When thermal runaway occurs in the battery cell, a large amount of gas will be generated, and an explosion-proof valve is required for exhaust. The explosion-proof valve is usually provided on the cover plate, and a through hole is provided at a position of the support member corresponding to the explosion-proof valve to ensure the smoothness of the exhaust passage by opening the through hole.

[0004] However, when thermal runaway of the battery cell occurs violently, a large amount of gas generation will push the pole group against the support member, resulting in the pole group blocking the through hole of the support member, affecting the smooth exhaust inside the battery cell and posing a safety hazard. Summary of the Utility Model

[0005] In view of this, the utility model provides a battery structure and an electric device to solve the problem that the pole group is prone to block the exhaust passage when thermal runaway of the battery cell occurs violently.

[0006] In a first aspect, the utility model provides a battery structure, including:

[0007] A housing, on which an opening is formed;

[0008] A cover plate, covering the opening of the housing, and the cover plate and the housing jointly enclose a receiving cavity; the cover plate is provided with an explosion-proof valve;

[0009] A pole group, disposed in the receiving cavity;

[0010] An end plate, disposed on a side of the pole group close to the cover plate. Defining the direction perpendicular to the plane where the cover plate is located as the first direction, at least an area of the end plate overlapping with the projection of the explosion-proof valve along the first direction forms a support plate body;

[0011] The support plate body is formed with a thinning band, and the thickness of at least a part of the thinning band is less than the thickness of the support plate body. In a heated state higher than the melting point of the end plate, the thinning band melts prior to the support plate body area.

[0012] Beneficial effects: In the battery structure provided by the embodiment of the present utility model, the support plate body is formed with a thinning belt, and the thickness of at least part of the area of the thinning belt is less than the thickness of the support plate body. When the end plate is in a heated state above the melting point, the thinning belt melts prior to the area of the support plate body. Thus, when thermal runaway occurs, the thinning belt melts rapidly, and then the interior of the area enclosed by the thinning belt detaches relative to the support plate body, increasing the exhaust space, ensuring that there is sufficient exhaust area at the position of the end plate corresponding to the explosion-proof valve, preventing the support part of the end plate from being blocked by the electrode group, providing a safe and stable exhaust channel, and thus ensuring that the gas inside the battery cell can be rapidly discharged, improving the safety of the battery cell.

[0013] In an alternative embodiment, a detachment part is formed inside the area enclosed by the thinning belt, and a support body part is formed in the area of the support plate body outside the area enclosed by the thinning belt;

[0014] After the thinning belt melts, the detachment part is adapted to separate from the support body part.

[0015] Beneficial effects: The thinning belt divides the support plate body into a detachment part and a support body part. Thus, when thermal runaway occurs, the thinning belt melts rapidly, and the detachment part can detach relative to the support body part, so that only the support body part remains on the support plate body. While ensuring the support for the battery cell, the exhaust area is increased, preventing the explosion-proof valve from being blocked by the electrode group, and providing a safe and stable exhaust channel.

[0016] In an alternative embodiment, the thinning belt includes a thinning annular groove, and the thinning annular groove separates the detachment part from the support body part;

[0017] The thinning belt further includes connecting ribs, and a plurality of connecting ribs are arranged at intervals in the thinning annular groove to connect the detachment part to the support body part.

[0018] Beneficial effects: The thinning belt includes a thinning annular groove and connecting ribs. A plurality of connecting ribs are arranged at intervals in the thinning annular groove, and the detachment part and the support body part are connected by a plurality of connecting ribs. This can not only ensure the connection effect between the two, but also enable the connecting ribs to melt preferentially when thermal runaway occurs, thus facilitating the detachment of the detachment part relative to the support body part.

[0019] In an alternative embodiment, along the first direction, the thickness of the connecting rib is d, and the thickness of the support plate body is D, and they satisfy: d < D.

[0020] Beneficial effects: By making the thickness d of the connecting rib smaller than the thickness D of the support plate body, the connecting function of the connecting rib is realized, ensuring that the detachment part and the support body part form an integral support plate body under normal use conditions; and because the thickness d of the connecting rib is small, when thermal runaway occurs, the connecting rib can melt prior to other areas of the support plate body, facilitating the detachment of the detachment part relative to the support body part to increase the exhaust area of the end plate.

[0021] In an alternative embodiment, the end plate has a support portion that abuts against the electrode group, and the support plate body is formed by the end plate on the side of the support portion close to the electrode group.

[0022] In an alternative embodiment, the support portion further forms a spacer cavity, and the spacer cavity is located between the support plate body and the explosion-proof valve along the first direction.

[0023] In an alternative embodiment, the support plate body is formed with a plurality of exhaust holes penetrating along the first direction, and the projection of at least part of the exhaust holes along the first direction overlaps with the explosion-proof valve.

[0024] In an alternative embodiment, at least part of the exhaust holes are formed in the detachment part.

[0025] Beneficial effects: By forming at least part of the exhaust holes in the detachment part, on the one hand, the exhaust efficiency of the detachment part can be ensured. After the detachment part detaches relative to the support body part, the detachment part moves towards the explosion-proof valve. Even if the detachment part fits at the position of the explosion-proof valve, there is still a certain exhaust space to ensure smooth exhaust. On the other hand, under normal use conditions, the electrolyte can enter the accommodation cavity through the exhaust holes, preventing part of the electrolyte from remaining on the support plate body.

[0026] In an alternative embodiment, in a cross-section perpendicular to the first direction, the shape of the thinning band includes: a runway shape, a polygon, a circle, or an ellipse.

[0027] In a second aspect, the present invention further provides an electrical device, including: the battery structure as described above.

[0028] Since the electrical device includes the battery structure and has the same effects as the battery structure, they will not be elaborated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0030] Figure 1 Schematic diagram of the battery structure of the present utility model;

[0031] Figure 2 Schematic diagram of the end plate of the present utility model;

[0032] Figure 3 is Figure 2 partial enlarged view;

[0033] Figure 4 Enlarged view of the top view state of the end plate of the present utility model;

[0034] Figure 5 is Figure 4 schematic diagram of the A-A cross-section in

[0035] Explanation of reference numerals:

[0036] 1. Housing; 2. Electrode group; 3. End plate; 4. Cover plate; 41. Explosion-proof valve;

[0037] 31. Support part; 32. Exhaust hole; 33. Thinning band; 331. Thinning ring groove; 332. Connecting rib; 34. Detachment part; 35. Spacing cavity; 36. Support body part; 37. Support plate body. Detailed implementation manners

[0038] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0039] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present utility model. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0040] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0041] In addition, the technical features involved in different embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0042] The battery cell generally includes a housing, a pole group disposed in the housing, and a cover plate covering the opening of the housing. Between the cover plate and the pole group, by providing a support member, in this embodiment, the support member can be an end plate 3, and the end plate 3 can support and fix the pole group to ensure the support strength at its support position.

[0043] In some alternative embodiments, both ends of the end plate 3 in the length direction are used for hot melting with the bare battery cell insulating sheet, so as to form a structural form that wraps the pole group on three sides. The bare battery cell insulating sheet achieves the insulation effect between the pole group and the housing. Through shape adaptation, the end plate 3 can support and protect the bending position of the pole ear, preventing the situation that the pole ear is stretched and damaged and then pierces the bare battery cell insulating sheet to cause a short circuit of the battery cell.

[0044] Since a large amount of gas will be generated when the battery cell undergoes thermal runaway, an explosion-proof valve is required for exhaust. The explosion-proof valve is usually provided on the cover plate. A through hole is provided at the position of the end plate 3 corresponding to the explosion-proof valve, and the through hole is opened to ensure the smoothness of the exhaust passage.

[0045] However, when the thermal runaway of the battery cell progresses violently, a large amount of gas production will push the position of the pole group, causing the pole group to press against the end plate 3, resulting in the blockage of the through hole of the end plate 3 by the pole group, affecting the smooth exhaust inside the battery cell and posing a safety hazard.

[0046] The battery structure provided by the embodiment of the present utility model can ensure that there is sufficient exhaust area at the position of the end plate 3 corresponding to the explosion-proof valve under the condition of thermal runaway of the battery cell, and it will not be blocked by the pole group, providing a safe and stable exhaust passage, so as to ensure that the gas inside the battery cell can be quickly discharged and improve the safety of the battery cell.

[0047] The following combines Figures 1 to 5 , to describe the embodiments of the present utility model.

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

[0049] A housing 1, on which an opening is formed;

[0050] A cover plate 4 is provided at the opening of the housing 1. The cover plate 4 and the housing 1 together enclose a receiving cavity. The cover plate 4 is provided with an explosion-proof valve 41.

[0051] A pole group 2 is disposed in the receiving cavity.

[0052] An end plate 3 is disposed on the side of the pole group 2 close to the cover plate 4. Define the direction perpendicular to the plane where the cover plate 4 is located as the first direction. The end plate 3 forms a support plate body 37 in the region that at least overlaps the projection of the explosion-proof valve 41 along the first direction.

[0053] The support plate body 37 is formed with a thinning band 33. The thickness of at least part of the thinning band 33 is less than the thickness of the support plate body 37. In a heated state higher than the melting point of the end plate 3, the thinning band 33 melts prior to the region of the support plate body 37.

[0054] The end plate 3 is disposed on the side of the pole group 2 close to the cover plate 4. After the battery structure is assembled, the end plate 3 can ensure the abutment of the end plate 3 against the pole group 2, realize the support and fixation of the pole group 2, and ensure the support strength at the support location.

[0055] At the same time, the end plate 3 in this embodiment can reserve a layout position for the pole tabs of the pole group 2, improving the space utilization rate.

[0056] Define the direction perpendicular to the plane where the cover plate 4 is located as the first direction. In this embodiment, the first direction is the direction in which the pole group 2 is inserted into the housing 1, that is, the opening direction of the explosion-proof valve 41.

[0057] In some embodiments, as shown in Figure 2 The end plate 3 has a support portion 31 that abuts against the pole group 2. The support portion 31 includes a support plate body 37. In this embodiment, the end plate 3 forms a support plate body 37 in the region that at least overlaps the projection of the explosion-proof valve 41 along the first direction. The support plate body 37 is formed by the end plate on the side of the support portion 31 close to the pole group 2.

[0058] In some embodiments, as shown in Figure 3 The support plate body 37 is formed with a plurality of exhaust holes 32 penetrating along the first direction. The projection of at least part of the exhaust holes 32 along the first direction overlaps with the explosion-proof valve 41.

[0059] By providing the exhaust holes 32 in the support plate body 37 and the projection of at least part of the exhaust holes 32 along the first direction overlapping with the explosion-proof valve 41, when the battery structure undergoes thermal runaway, an exhaust channel can be formed in the region where the end plate 3 overlaps with the explosion-proof valve 41 along the first direction, ensuring the smooth progress of exhaust.

[0060] In some embodiments, as shown in Figure 5As shown, an interval cavity 35 is further formed in the support portion 31. The interval cavity 35 is located between the support plate body 37 and the explosion-proof valve 41 along the first direction.

[0061] By forming the interval cavity 35 between the support plate body 37 and the explosion-proof valve 41, it can ensure that the end plate 3 forms a gas storage space, avoiding the situation where when the exhaust is too fast, a large amount of gas flows towards the explosion-proof valve 41, resulting in excessive air pressure in the battery structure and preventing a large amount of gas from deforming the housing 1 by extrusion.

[0062] In the battery structure provided by the embodiment of the present invention, a thinning band 33 is formed in the support plate body 37. The thickness of at least a part of the thinning band 33 is less than the thickness of the support plate body 37. When the end plate 3 is in a heated state above the melting point, the thinning band 33 melts prior to the area of the support plate body 37. Thus, during thermal runaway, the thinning band 33 melts quickly, and then the interior of the area enclosed by the thinning band 33 detaches relative to the support plate body 37, increasing the exhaust space, ensuring that there is sufficient exhaust area at the position of the end plate 3 corresponding to the explosion-proof valve, preventing the support portion 31 of the end plate 3 from being blocked by the electrode group, providing a safe and stable exhaust channel, and thus ensuring that the gas inside the battery cell can be quickly discharged and improving the safety of the battery cell.

[0063] In some embodiments, as shown in combination Figure 4 An exfoliation portion 34 is formed inside the area enclosed by the thinning band 33, and the area of the support plate body 37 outside the area enclosed by the thinning band 33 forms a support body portion 36;

[0064] After the thinning band 33 melts, the exfoliation portion 34 is adapted to separate from the support body portion 36.

[0065] The thinning band 33 divides the support plate body 37 into the exfoliation portion 34 and the support body portion 36. Thus, during thermal runaway, the thinning band 33 melts quickly, and the exfoliation portion 34 can detach relative to the support body portion 36, so that only the support body portion 36 remains on the support plate body 37. While ensuring the support for the battery cell, the exhaust area is increased, preventing the explosion-proof valve 41 from being blocked by the electrode group, and providing a safe and stable exhaust channel.

[0066] In some embodiments, as shown in combination Figure 4 The thinning band 33 includes a thinning annular groove 331, and the thinning annular groove 331 spaces the exfoliation portion 34 and the support body portion 36 apart;

[0067] The thinning band 33 further includes connecting ribs 332. A plurality of connecting ribs 332 are spaced in the thinning annular groove 331 to connect the exfoliation portion 34 to the support body portion 36.

[0068] The thinning belt 33 includes a thinning annular groove 331 and connecting ribs 332. A plurality of connecting ribs 332 are arranged at intervals in the thinning annular groove 331. The shedding part 34 and the supporting body part 36 are connected by a plurality of connecting ribs 332, which can not only ensure the connection effect between the two, but also enable the connecting ribs 332 to melt preferentially when thermal runaway occurs, so as to facilitate the shedding of the shedding part 34 relative to the supporting body part 36.

[0069] In some embodiments, as shown in Figure 5 along the first direction, the thickness of the connecting rib 332 is d, and the thickness of the support plate body 37 is D, and it satisfies: d < D.

[0070] By making the thickness d of the connecting rib 332 less than the thickness D of the support plate body 37, the connecting function of the connecting rib 332 is realized, ensuring that the shedding part 34 and the supporting body part 36 form an integral support plate body 37 under normal use conditions; and because the thickness d of the connecting rib 332 is small, when thermal runaway occurs, the connecting rib 332 can melt prior to other areas of the support plate body 37, facilitating the shedding of the shedding part 34 relative to the supporting body part 36 to increase the exhaust area of the end plate 3.

[0071] In some embodiments, as shown in Figure 4 at least part of the exhaust holes 32 are formed in the shedding part 34.

[0072] By making at least part of the exhaust holes 32 formed in the shedding part 34, on the one hand, the exhaust efficiency of the shedding part 34 can be ensured. After the shedding part 34 falls off relative to the supporting body part 36, the shedding part 34 moves towards the explosion-proof valve 41. Even if the shedding part 34 fits at the position of the explosion-proof valve 41, there is still a certain exhaust space to ensure smooth exhaust. On the other hand, under normal use conditions, the electrolyte can enter the accommodation cavity through the exhaust holes 32, preventing part of the electrolyte from remaining on the support plate body 37.

[0073] In some embodiments, in a cross-section perpendicular to the first direction, the shape of the thinning belt 33 includes: a racetrack shape, a polygon, a circle, an ellipse, etc.

[0074] The shape of the thinning belt 33 can be various, as long as it ensures that when thermal runaway occurs, the connecting rib 332 can melt prior to other areas of the support plate body 37, facilitating the shedding of the shedding part 34 relative to the supporting body part 36.

[0075] According to an embodiment of the present invention, on the other hand, an electrical device is also provided, including: the battery structure as described above.

[0076] Obviously, the above embodiments are only examples for clear illustration and not limitations on the implementation manners. Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the present invention.

Claims

1. A battery structure, characterized in that: include: A housing (1) having an opening formed thereon; A cover plate (4) is arranged to cover the opening of the shell (1), and the cover plate (4) and the shell (1) together enclose a receiving cavity; the cover plate (4) is provided with an explosion-proof valve (41); A pole group (2) is arranged in the accommodation cavity; An end plate (3) is arranged on a side of the electrode group (2) close to the cover plate (4), and a direction perpendicular to the plane where the cover plate (4) is located is defined as a first direction. The region of the end plate (3) that overlaps at least with the projection of the explosion-proof valve (41) along the first direction forms a support plate body (37); The support plate body (37) is formed with a thinning band (33), and the thickness of at least a part of the thinning band (33) is less than the thickness of the support plate body (37). When heated at a temperature higher than the melting point of the end plate (3), the thinning band (33) melts before the support plate body (37) region.

2. The battery structure according to claim 1, characterized in that: The inside of the enclosed area of ​​the thinning belt (33) forms a fall-off portion (34), and the area of ​​the support plate (37) located outside the enclosed area of ​​the thinning belt (33) forms a support body portion (36); After the thinning strip (33) is melted, the fall-off portion (34) is suitable for being separated from the supporting body portion (36).

3. The battery structure according to claim 2, characterized in that: The thinning belt (33) comprises a thinning annular groove (331), and the thinning annular groove (331) enables the falling portion (34) and the supporting body portion (36) to be spaced apart. The thinning belt (33) further comprises connecting ribs (332), and a plurality of the connecting ribs (332) are arranged at intervals in the thinning annular groove (331) to connect the falling portion (34) to the supporting body portion (36).

4. The battery structure according to claim 3, characterized in that: Along the first direction, the thickness of the connecting rib (332) is d, the thickness of the supporting plate body (37) is D, and the following condition is satisfied: d<D.

5. The battery structure according to any one of claims 1 to 4, characterized in that: The end plate (3) has a support portion (31) abutting against the pole group (2), and the support plate body (37) is formed by the end plate on a side of the support portion (31) close to the pole group (2).

6. The battery structure according to claim 5, characterized in that: The support portion (31) is further formed with a spacer cavity (35), and the spacer cavity (35) is located between the support plate body (37) and the explosion-proof valve (41) along a first direction.

7. The battery structure according to claim 2, characterized in that: The support plate body (37) is penetrated by a plurality of exhaust holes (32) along a first direction, and projections of at least some of the exhaust holes (32) along the first direction overlap with the explosion-proof valve (41).

8. The battery structure according to claim 7, characterized in that: At least part of the exhaust holes (32) are formed in the falling portion (34).

9. The battery structure according to any one of claims 1 to 4, characterized in that: In a cross section perpendicular to the first direction, the shape of the thinned strip (33) includes: a racetrack shape, a polygonal shape, a circular shape, or an elliptical shape.

10. An electrical device, characterized in that: The battery structure comprises the battery structure as claimed in any one of claims 1 to 9.

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