Battery and battery pack

Abstract

The utility model relates to the technical field of batteries, and provides a battery and a battery pack. A battery cell; the pole assembly is arranged on the first end wall, a nick is formed in the first end wall to form an anti-explosion valve, and the nick is arranged around the pole assembly; the current collecting piece is arranged in the battery shell, and the pole assembly is electrically connected with the tab through the current collecting piece; wherein the current collecting piece comprises a main body section and a cantilever section, the cantilever section is connected to the main body section, the cantilever section is arranged in a turnover mode relative to the main body section, the pole column assembly is connected with the cantilever section, the pole lug is connected with the main body section, and at least part of orthographic projection, facing the first end wall, of the cantilever section is located in an area defined by the nick. And the cantilever section can be deformed and folded along with the pole assembly, so that the resistance to the anti-explosion valve is reduced, the opening height of the anti-explosion valve is increased, internal air pressure can be quickly discharged, and the safe use performance of the battery is effectively improved.

Description

Technical Field

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

[0002] In the related art, a battery may include a battery housing and an explosion-proof valve. The explosion-proof valve may be disposed on the battery housing. After the internal pressure of the battery housing reaches the opening pressure of the explosion-proof valve, the explosion-proof valve may open, thereby realizing the pressure relief of the battery. However, due to the limitation of the internal structure of the battery housing, after the explosion-proof valve opens, it will affect the gas release rate. Summary of the Utility Model

[0003] The utility model provides a battery and a battery pack to improve the use performance of the battery.

[0004] According to one aspect of the utility model, a battery is provided, including:

[0005] A battery housing, the battery housing includes a first end wall, a second end wall and a side wall, and the opposite first end wall and second end wall are respectively connected to opposite ends of the side wall;

[0006] A battery cell, the battery cell is disposed in the battery housing, the battery cell includes a battery cell main body and a tab, and the tab extends from the battery cell main body;

[0007] A terminal assembly, the terminal assembly is disposed on the first end wall, and a notch is provided on the first end wall to form an explosion-proof valve, and the notch is disposed around the terminal assembly;

[0008] A current collector, the current collector is disposed in the battery housing and is located between the first end wall and the battery cell main body, and the terminal assembly is electrically connected to the tab through the current collector;

[0009] Wherein, the current collector includes a main body section and a cantilever section, the cantilever section is connected to the main body section, and a weak area is formed between the cantilever section and the main body section, so that the cantilever section is foldably disposed relative to the main body section, the terminal assembly is directly fixedly electrically connected to the cantilever section, the tab is directly fixedly electrically connected to the main body section, and at least a part of the positive projection of the cantilever section facing the first end wall is located in the area surrounded by the notch.

[0010] The battery of the embodiment of the present utility model includes a battery housing, a battery cell, a pole column assembly and a current collector. The battery cell is disposed within the battery housing, the pole column assembly is disposed on the first end wall of the battery housing, the current collector is disposed within the battery housing, and the pole column assembly is electrically connected to the tab on the main body of the battery cell through the current collector. A notch is provided on the first end wall and is disposed around the pole column assembly to form an explosion-proof valve. Thus, after the internal pressure of the battery reaches a certain height, the notch can burst, and further the pressure relief of the battery is realized. By making the current collector include a main body section and a cantilever section, the cantilever section is connected to the main body section, and a weak area is formed between the cantilever section and the main body section, so that the cantilever section is flipably disposed relative to the main body section. The pole column assembly is connected to the cantilever section, the tab is connected to the main body section, and at least a part of the orthographic projection of the cantilever section facing the first end wall is located within the area surrounded by the notch. Thus, when the explosion-proof valve is opened, the cantilever section can be deformed and flipped along with the pole column assembly, thereby reducing the resistance to the explosion-proof valve, increasing the opening height of the explosion-proof valve, enabling the internal air pressure to be quickly discharged, and effectively improving the safe use performance of the battery.

[0011] According to another aspect of the present utility model, a battery pack is provided, including the above-mentioned battery.

[0012] The battery of the battery pack of the embodiment of the present utility model includes a battery housing, a battery cell, a pole column assembly and a current collector. The battery cell is disposed within the battery housing, the pole column assembly is disposed on the first end wall of the battery housing, the current collector is disposed within the battery housing, and the pole column assembly is electrically connected to the tab on the main body of the battery cell through the current collector. A notch is provided on the first end wall and is disposed around the pole column assembly to form an explosion-proof valve. Thus, after the internal pressure of the battery reaches a certain height, the notch can burst, and further the pressure relief of the battery is realized. By making the current collector include a main body section and a cantilever section, the cantilever section is connected to the main body section, and a weak area is formed between the cantilever section and the main body section, so that the cantilever section is flipably disposed relative to the main body section. The pole column assembly is connected to the cantilever section, the tab is connected to the main body section, and at least a part of the orthographic projection of the cantilever section facing the first end wall is located within the area surrounded by the notch. Thus, when the explosion-proof valve is opened, the cantilever section can be deformed and flipped along with the pole column assembly, thereby reducing the resistance to the explosion-proof valve, increasing the opening height of the explosion-proof valve, enabling the internal air pressure to be quickly discharged, and effectively improving the safe use performance of the battery pack. Description of the Drawings

[0013] For a better understanding of the present disclosure, reference may be made to the embodiments shown in the following drawings. The components in the drawings are not necessarily to scale, and related elements may be omitted to emphasize and clearly illustrate the technical features of the present disclosure. Additionally, related elements or components may have different arrangements as known in the art. Moreover, in the drawings, the same reference numerals denote the same or similar components in each drawing. Wherein:

[0014] Figure 1 is a schematic structural view of a battery from one perspective shown according to an exemplary embodiment;

[0015] Figure 2 is a schematic structural view of a battery from another perspective shown according to an exemplary embodiment;

[0016] Figure 3 is a schematic partial cross-sectional structural view of a battery shown according to an exemplary embodiment;

[0017] Figure 4 is a schematic structural view of a current collector of a battery from one perspective shown according to an exemplary embodiment;

[0018] Figure 5 is a schematic structural view of a current collector of a battery from another perspective shown according to an exemplary embodiment;

[0019] Figure 6 is a schematic structural view of a current collector of a battery shown according to another exemplary embodiment;

[0020] Figure 7 is a schematic structural view of a battery cell of a battery shown according to an exemplary embodiment.

[0021] The reference numerals are explained as follows:

[0022] 10. Battery housing; 11. First end wall; 111. Notch; 12. Second end wall; 13. Side wall; 20. Battery cell; 21. Battery cell main body; 211. Winding core hole; 22. Tab; 30. Terminal assembly; 31. Groove; 40. Current collector member; 41. Main body section; 42. Cantilever section; 421. Protrusion; 422. Straight line; 423. Arc; 43. Notch. Detailed implementation manners

[0023] Next, the technical solutions in the exemplary embodiments of the present disclosure will be clearly and completely described in conjunction with the accompanying drawings in the exemplary embodiments of the present disclosure. The exemplary embodiments described herein are only for illustrative purposes and are not intended to limit the protection scope of the present disclosure. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the protection scope of the present disclosure.

[0024] In the description of the present disclosure, unless otherwise clearly defined and limited, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance; the term "plurality" means two or more; the term "and / or" includes any combination and all combinations of one or more of the associated listed items. In particular, referring to "the / this" object or "one" object also intends to represent one of the possible multiple such objects.

[0025] Unless otherwise specified or stated, terms such as "connected" and "fixed" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, an integral connection, an electrical connection, or a signal connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this disclosure can be understood according to specific circumstances.

[0026] Furthermore, in the description of this disclosure, it should be understood that the orientation terms such as "upper", "lower", "inner", and "outer" described in the exemplary embodiments of this disclosure are described from the angles shown in the drawings and should not be construed as a limitation on the exemplary embodiments of this disclosure. It should also be understood that in the context, when it is mentioned that an element or feature is connected "on", "under", or "inside", "outside" another element (one or more), it can not only be directly connected "on", "under", or "inside", "outside" another element (one or more), but also be indirectly connected "on", "under", or "inside", "outside" another element (one or more) through an intermediate element.

[0027] An embodiment of the present utility model provides a battery. Please refer to Figures 1 to 7 , the battery includes: a battery housing 10, the battery housing 10 includes a first end wall 11, a second end wall 12, and a side wall 13, and the opposite first end wall 11 and second end wall 12 are respectively connected to opposite ends of the side wall 13; a battery cell 20, the battery cell 20 is disposed in the battery housing 10, the battery cell 20 includes a battery cell main body 21 and a tab 22, and the tab 22 extends from the battery cell main body 21; a terminal assembly 30, the terminal assembly 30 is disposed on the first end wall 11, and a notch 111 is provided on the first end wall 11 to form an explosion-proof valve, and the notch 111 is disposed around the terminal assembly 30; a current collector 40, the current collector 40 is disposed in the battery housing 10 and is located between the first end wall 11 and the battery cell main body 21, and the terminal assembly 30 is electrically connected to the tab 22 through the current collector 40; wherein, the current collector 40 includes a main body section 41 and a cantilever section 42, the cantilever section 42 is connected to the main body section 41, and a weak area is formed between the cantilever section 42 and the main body section 41 so that the cantilever section 42 is foldably disposed relative to the main body section 41, the terminal assembly 30 is directly fixedly electrically connected to the cantilever section 42, the tab 22 is directly fixedly electrically connected to the main body section 41, and the positive projection of the cantilever section 42 facing the first end wall 11 is at least partially located in the area surrounded by the notch 111.

[0028] A battery according to an embodiment of the present utility model includes a battery housing 10, an electrode core 20, a terminal assembly 30, and a current collector 40. The electrode core 20 is disposed inside the battery housing 10, the terminal assembly 30 is disposed on the first end wall 11 of the battery housing 10, the current collector 40 is disposed inside the battery housing 10, and the terminal assembly 30 is electrically connected to the tab 22 on the electrode core body 21 through the current collector 40. A notch 111 is provided on the first end wall 11 around the terminal assembly 30 to form an explosion-proof valve. Thus, after the internal pressure of the battery reaches a certain height, the notch 111 can burst, thereby realizing pressure relief of the battery. By making the current collector 40 include a main body section 41 and a cantilever section 42, the cantilever section 42 is connected to the main body section 41, and a weak area is formed between the cantilever section 42 and the main body section 41, so that the cantilever section 42 is disposed relative to the main body section 41 in a foldable manner. The terminal assembly 30 is connected to the cantilever section 42, the tab 22 is connected to the main body section 41, and the orthographic projection of the cantilever section 42 facing the first end wall 11 is at least partially located within the area surrounded by the notch 111. Thus, when the explosion-proof valve is opened, the cantilever section 42 can be deformed and folded along with the terminal assembly 30, thereby reducing the resistance to the explosion-proof valve and increasing the opening height of the explosion-proof valve, enabling the internal air pressure to be quickly discharged, and effectively improving the safe use performance of the battery.

[0029] It should be noted that, as shown in Figure 1 the battery housing 10 includes a first end wall 11, a second end wall 12, and a side wall 13. The opposite first end wall 11 and second end wall 12 are respectively connected to opposite ends of the side wall 13. The battery housing 10 is a metal housing. For example, the battery housing 10 is an aluminum shell, or the battery housing 10 is a steel shell, etc.

[0030] As Figure 2 shown, a notch 111 is provided on the first end wall 11 to form an explosion-proof valve. Thus, after the internal pressure of the battery reaches a certain height, the notch 111 can burst, thereby realizing timely release of the pressure. The notch 111 can be formed by material removal, or the notch 111 can be achieved by extrusion to reduce the thickness, etc., which is not limited herein.

[0031] As Figure 3 shown, the electrode core 20 is disposed inside the battery housing 10. The electrode core 20 includes an electrode core body 21 and a tab 22. The tab 22 extends from the electrode core body 21. The terminal assembly 30 is disposed on the first end wall 11, and the terminal assembly 30 can be electrically connected to the tab 22 through the current collector 40.

[0032] Combined with Figure 7As shown, two tabs 22 can be provided on the battery cell body 21. The two tabs 22 can be a positive tab and a negative tab respectively. One of the two tabs 22 can be electrically connected to the terminal assembly 30, and the other can be electrically connected to the battery housing 10. Alternatively, there can also be two terminal assemblies 30. The two tabs 22 can be electrically connected to the two terminal assemblies 30 respectively, and the two terminal assemblies 30 can be provided on the first end wall 11 and the second end wall 12 respectively.

[0033] Combined with Figures 3 to 5 As shown, the current collector 40 includes a main body section 41 and a cantilever section 42. The cantilever section 42 is connected to the main body section 41. The terminal assembly 30 is connected to the cantilever section 42, and the tab 22 is connected to the main body section 41. When the notch 111 bursts, since the notch 111 is arranged around the terminal assembly 30, the terminal assembly 30 will drive the area surrounded by the notch 111 of the first end wall 11 to move. And the cantilever section 42 is arranged to be foldable relative to the main body section 41. Therefore, it can make the area surrounded by the notch 111 of the first end wall 11 have a relatively large opening, so as to improve the release efficiency of the gas inside the battery.

[0034] The terminal assembly 30 is directly fixedly electrically connected to the cantilever section 42, that is, no third component needs to be provided between the terminal assembly 30 and the cantilever section 42. For example, connection methods such as welding and riveting are used; the tab 22 is directly fixedly electrically connected to the main body section 41, that is, no third component needs to be provided between the tab 22 and the main body section 41, and the two are directly connected. For example, connection methods such as welding are used.

[0035] The notch 111 is arranged around the terminal assembly 30. The notch 111 can be continuously arranged, or the notch 111 can also be discontinuously arranged.

[0036] And the positive projection of the cantilever section 42 towards the first end wall 11 is at least partially located in the area surrounded by the notch 111. Thus, it can be more convenient for the terminal assembly 30 to drive the cantilever section 42 to fold, so as to ensure that the area surrounded by the notch 111 of the first end wall 11 can have a relatively large opening, and further improve the gas discharge efficiency.

[0037] A weak area is formed between the cantilever section 42 and the main body section 41, so that after the notch 111 bursts, the cantilever section 42 can efficiently fold relative to the main body section 41, so as to ensure the rapid formation of pressure release inside the battery and improve the safe use performance of the battery.

[0038] The existence of the weak area can facilitate the formation of the cantilever section 42, so as to ensure that the cantilever section 42 can fold relative to the main body section 41.

[0039] At least a part of the cantilever segment 42 is connected to the terminal assembly 30. The cantilever segment 42 can be folded relative to the main body segment 41, that is, the weak area between the cantilever segment 42 and the main body segment 41 enables the cantilever segment 42 to be easily deformed relative to the main body segment 41, thereby achieving folding. The cantilever segment 42 is a segment extending from the main body segment 41, so as to form a connection with the terminal assembly 30 and can be folded.

[0040] In one embodiment, as Figure 4 shown, the weak area includes at least one notch 43, so that the cantilever segment 42 can be easily folded relative to the main body segment 41.

[0041] In one embodiment, as Figure 4 shown, there are two notches 43, and the two notches 43 are respectively located on opposite sides of the cantilever segment 42.

[0042] Notches 43 are provided on opposite sides of the cantilever segment 42, whereby the cantilever segment 42 can be easily formed, and the stress can be concentrated on the cantilever segment 42, facilitating the bending deformation of the cantilever segment 42.

[0043] In one embodiment, as Figure 6 shown, there can be one notch 43.

[0044] In one embodiment, the depth of the notch 43 is not less than 2 mm, whereby a relatively large length of the cantilever segment 42 can be ensured, so as to ensure that the cantilever segment 42 can be folded under the drive of a relatively small force, improving the opening efficiency of the explosion-proof valve and further improving the internal pressure release efficiency of the battery.

[0045] The depth of the notch 43 can be 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 7 mm or 8 mm, etc.

[0046] In one embodiment, the width range between opposite sides of the notch 43 is 1 mm - 3 mm. If the notch 43 is too small, it is easy to interfere with other adjacent structures when the cantilever segment 42 is folded, and the processing difficulty is large; if the notch 43 is too large, the length of the edge of the current collector 40 will be reduced, so the connection area between the current collector 40 and the insulating part will be reduced, affecting the connection strength of the insulating part.

[0047] The width between opposite sides of the notch 43 can be 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, 2 mm, 2.2 mm, 2.5 mm, 2.8 mm or 3 mm, etc.

[0048] The width between opposite sides of the notch 43 is the vertical distance between opposite sides of the notch 43.

[0049] It should be noted that the weak area includes at least one notch 43. The notch 43 is located between the cantilever section 42 and the main body section 41. The opening of the notch 43 faces the side of the cantilever section 42 away from the main body section 41, thereby forming a weak area, enabling the cantilever section 42 to be folded relative to the main body section 41. The extending direction of the notch 43 can form an angle with the edge of the main body section 41 close to the cantilever section 42. For example, the extending direction of the notch 43 and the edge of the main body section 41 close to the cantilever section 42 is a right angle, or an acute angle, etc.

[0050] In one embodiment, the weak area can be a thinning structure. For example, the thickness of the thinning structure can be relatively small. When the explosion-proof valve is opened, the weak area can be disconnected, thereby forming the cantilever section 42, ensuring that the cantilever section 42 can be folded relative to the main body section 41. There can be two thinning structures, and the two thinning structures are respectively located on opposite sides of the cantilever section 42, so as to facilitate the folding of the cantilever section 42 relative to the main body section 41 when the thinning structure is disconnected.

[0051] In one embodiment, the main body section 41 is arranged around the cantilever section 42, that is, at least part of the cantilever section 42 is surrounded by the main body section 41, facilitating the formation of the center of stress concentration and enabling the cantilever section 42 to deform rapidly.

[0052] Combined Figures 4 to 6 As shown, the main body section 41 is arranged around the cantilever section 42, that is, a part of the cantilever section 42 can be located inside the space formed by the surrounding of the main body section 41.

[0053] In one embodiment, the main body section 41 is arranged on one side of the cantilever section 42, so that a part of the cantilever section 42 can extend out from the inside of the space formed by the main body section 41. This can not only facilitate the deformation and folding of the cantilever section 42, but also form a guiding effect, facilitating the installation and fixation of the current collector 40.

[0054] One end of the cantilever section 42 is connected to the main body section 41, and the other end of the cantilever section 42 is far from the main body section 41. The main body section 41 is arranged on one side of the cantilever section 42, that is, the cantilever section 42 protrudes from the main body section 41 as a whole, as Figure 4 shown.

[0055] In one embodiment, as Figure 7 shown, there are at least two tab ears 22. The at least two tab ears 22 include a positive tab ear and a negative tab ear. The positive tab ear and the negative tab ear extend from the same side of the battery cell main body 21. This can not only ensure the over-current balance of the positive and negative poles of the battery, avoid the over-current of the other polar tab ear being too narrow and the serious internal heat generation leading to abnormal explosion of the explosion-proof valve, but also reduce the height dimension of the battery cell 20, thereby reducing the height dimension of the battery and being beneficial to improving the energy density of the battery.

[0056] In some embodiments, it is not excluded that the positive electrode tab and the negative electrode tab can extend from opposite sides of the battery cell body 21.

[0057] In one embodiment, as shown in Figure 3 and Figure 4 , a groove 31 is provided on one side of the terminal assembly 30 facing the current collector 40, and a protrusion 421 is formed on one side of the cantilever section 42 facing the terminal assembly 30. At least a part of the protrusion 421 is inserted into the groove 31, which can not only ensure the fixed electrical connection ability between the terminal assembly 30 and the cantilever section 42, but also enable the terminal assembly 30 to deform rapidly with reduced weight, while forming a high degree of buffering, avoiding the connection between the battery cell 20 and the current collector 40, and the connection between the current collector 40 and the terminal assembly 30 from affecting the peeling of the explosion-proof valve, thereby ensuring the safety performance of the battery. In one embodiment, in the direction from the end of the cantilever section 42 away from the main body section 41 towards the end connected to the main body section 41, the length of the cantilever section 42 is L, in mm, the area enclosed by the notch 111 is S, in mm 2 , the capacity of the battery is A, in Ah, and L / (S×A) is 0.0001 - 0.003, which can further ensure that the explosion-proof valve can be opened to a certain height, enabling the gas generated inside the battery to be quickly discharged, thereby improving the safe use performance of the battery.

[0058] As shown in Figure 2 , the area enclosed by the notch 111 can be represented as S. When the notch 111 is a circumferentially closed structure, the area S enclosed by the notch 111 can be directly determined, as shown in Figure 2 . When the notch 111 is a circumferentially non-closed structure, for the determination of the area S enclosed by the notch 111, for example, if the notch 111 is arc-shaped, the notch 111 can be connected around the terminal assembly 30 to form a circumferentially closed structure for calculating the area S, for example, connected into a ring; or, if the notch 111 is linear, the notch 111 can be connected around the terminal assembly 30 to form a circumferentially closed structure for calculating the area S, for example, connected into a rectangle. Connecting the circumferentially non-closed notch 111 into a circumferentially closed structure around the terminal assembly 30 for calculation, the shape of the circumferentially closed structure formed and the circumferential outer edge of the terminal assembly 30 located outside the battery case 10 are basically the same.

[0059] As shown in Figure 5 , the direction from the end of the cantilever section 42 away from the main body section 41 towards the end connected to the main body section 41 can be represented as X. In the direction X of the cantilever section 42 from the end away from the main body section 41 towards the end connected to the main body section 41, the length of the cantilever section 42 can be represented as L, and the length of the cantilever section 42 is the distance from the end of the cantilever section 42 to the root where it is connected to the main body section 41.

[0060] When the area S enclosed by the notch 111 is relatively large, the length L of the cantilever segment 42 can be made relatively long to ensure that the explosion-proof valve opens to a certain height and the gas generated inside the battery is quickly discharged; when the capacity A of the battery is relatively large, more gas is generated, and the length L of the cantilever segment 42 can be made relatively long to quickly discharge the gas generated inside the battery.

[0061] L / (S×A) can be 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008, 0.0009, 0.001, 0.0015, 0.002, 0.0025, 0.0028, 0.0029 or 0.003, etc. Among them, the unit of L / (S×A) is (mm×Ah) -1 。

[0062] In one embodiment, the wall thickness at the root where the cantilever segment 42 is connected to the main body segment 41 is D. When D≥0.2mm, L / (S×A) is 0.0002 - 0.003. Furthermore, it can be ensured that the cantilever segment 42 can be deformed conveniently. When the explosion-proof valve opens, the cantilever segment 42 can be turned over, thereby efficiently realizing gas discharge.

[0063] When the wall thickness D at the root where the cantilever segment 42 is connected to the main body segment 41 is D≥0.2mm, that is, the wall thickness D at the root where the cantilever segment 42 is connected to the main body segment 41 is relatively large. Therefore, the length L of the cantilever segment 42 can be increased, thereby reducing the deformation difficulty of the cantilever segment 42. Thus, it can be ensured that the terminal assembly 30 can drive the cantilever segment 42 to turn over.

[0064] The wall thickness D at the root where the cantilever segment 42 is connected to the main body segment 41 can be 0.2mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm or 2mm, etc.

[0065] In one embodiment, in the direction from the end of the cantilever segment 42 far from the main body segment 41 towards the end connected to the main body segment 41, the length of the cantilever segment 42 is L, and the outer contour of the main body segment 41 facing away from the cantilever segment 42 includes an arc with a radius of R. R / L is 1 - 4. On the basis of ensuring the structural stability of the current collector 40, the folding ability of the cantilever segment 42 can also be ensured, thereby improving the safe use performance of the battery.

[0066] Combined Figure 5 As shown, the outer contour of the main body segment 41 facing away from the cantilever segment 42 includes an arc, and the radius of the arc can be represented as R. If the length L of the cantilever segment 42 is too long, it will affect the structural stability of the current collector 40, while if the length L of the cantilever segment 42 is too short, the deformation of the current collector 40 is limited, which is not conducive to improving the pressure relief efficiency.

[0067] The R / L can be 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, 3, 3.2, 3.5, 3.8, 4, etc.

[0068] In one embodiment, the length of the root where the cantilever segment 42 is connected to the main body segment 41 is H, with the unit of mm, and the capacity of the battery is A, with the unit of Ah. H / A is 0.1 - 0.7. On the basis of ensuring that the current collector 40 can have a reliable over-current capacity, the capacity requirement of the battery can be met accordingly, and it can be ensured that when the cantilever segment 42 is folded relative to the main body segment 41, it does not require too much force, thereby ensuring the pressure relief efficiency when the explosion-proof valve bursts.

[0069] Combined with Figure 5 and Figure 6 As shown, the length of the root where the cantilever segment 42 is connected to the main body segment 41 can be expressed as H. When the capacity A of the battery is relatively large, the length H of the root where the cantilever segment 42 is connected to the main body segment 41 can be relatively large, thereby meeting the over-current requirement of the current collector 40.

[0070] H / A can be 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, or 0.7, etc. The unit of H / A is mm / Ah.

[0071] Combined with Figure 5 As shown, the length H of the root where the cantilever segment 42 is connected to the main body segment 41 is the distance between the bottoms of the two notches 43.

[0072] Combined with Figure 6 As shown, the length H of the root where the cantilever segment 42 is connected to the main body segment 41 is the distance from the bottom end of the notch 43 to the connection point of the other side of the cantilever segment 42 and the main body segment 41.

[0073] In one embodiment, the length of the root where the cantilever segment 42 is connected to the main body segment 41 is H, and the area enclosed by the score line 111 is S. H / S is 0.009 mm -1 ~0.07 mm -1 , thereby ensuring that the cantilever segment 42 can be folded smoothly, ensuring that the explosion-proof valve can pop up reliably, and further forming a high-speed pressure relief of the battery.

[0074] If the area S enclosed by the score line 111 is too large and the length H of the root where the cantilever segment 42 is connected to the main body segment 41 is too small, it cannot support the popping of the explosion-proof valve, and the cantilever segment 42 may even break; if the area S enclosed by the score line 111 is too small and the length H of the root where the cantilever segment 42 is connected to the main body segment 41 is too large, after the explosion-proof valve pops up, the cantilever segment 42 and the explosion-proof valve will interfere with each other, blocking the popping of the explosion-proof valve, which is not conducive to improving the pressure relief capacity.

[0075] The H / S can be 0.009 mm -1 , 0.01 mm -1 , 0.015 mm -1 , 0.02 mm -1 , 0.025 mm -1 , 0.03 mm -1 , 0.035 mm -1 , 0.04 mm -1 , 0.045 mm -1 , 0.05 mm -1 , 0.055 mm -1 , 0.06 mm -1 , 0.065 mm -1 or 0.07 mm -1 and so on.

[0076] In one embodiment, the length of the root where the cantilever segment 42 is connected to the main body segment 41 is H, and H is 4 mm - 14 mm. This can not only ensure the current-carrying capacity of the current collector 40, but also ensure the deformation ability of the cantilever segment 42 relative to the main body segment 41, thereby facilitating the formation of pressure relief in the battery and improving the safe use performance of the battery.

[0077] The length H of the root where the cantilever segment 42 is connected to the main body segment 41 can be 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm, 12 mm, 12.5 mm, 13 mm, 13.5 mm or 14 mm and so on.

[0078] In one embodiment, as Figure 5 shown, the outer contour of the cantilever segment 42 includes an arc 423 and a straight line 422; wherein, the two opposite straight lines 422 are respectively connected to both ends of the arc 423. This can not only ensure that the cantilever segment 42 can be conveniently connected to the terminal assembly 30, but also ensure that the cantilever segment 42 itself can have a relatively reliable current-carrying capacity, avoiding the risk of burning out, thereby ensuring the safe use performance of the battery.

[0079] In one embodiment, as Figure 4 shown, a protrusion 421 is formed on the side of the cantilever segment 42 facing the terminal assembly 30, and the protrusion 421 is connected to the terminal assembly 30. Without increasing the overall volume of the cantilever segment 42, it can meet the connection between the protrusion 421 and the terminal assembly 30, facilitate the connection between the terminal assembly 30 and the current collector 40, and ensure the energy density of the battery.

[0080] In one embodiment, the battery is a cylindrical battery, and the terminal assembly 30, the first end wall 11, and the explosion-proof valve can form a concentric structure, which is convenient for stress concentration, facilitates the peeling of the explosion-proof valve, and thus improves the safety protection ability of the explosion-proof valve for the battery.

[0081] The cylindrical battery includes a battery core and an electrolyte, which is the smallest unit capable of performing electrochemical reactions such as charging / discharging. The battery core refers to a unit formed by winding or laminating a stacked portion, and the stacked portion includes a first electrode plate, a separator, and a second electrode plate. When the first electrode plate is a positive electrode plate, the second electrode plate is a negative electrode plate. Among them, the polarities of the first electrode plate and the second electrode plate can be interchanged. The first electrode plate and the second electrode plate are coated with active substances. The first electrode plate, the second electrode plate having the opposite electrical property to the first electrode plate, and the separator sheet disposed between the first electrode plate and the second electrode plate are wound to obtain a wound battery core.

[0082] In one embodiment, as Figure 3 and Figure 7 shown, the battery core body 21 is formed with a core hole 211. Along the axial direction of the core hole 211, at least a part of the cantilever section 42 coincides with the positive projection of the core hole 211 on the same plane, that is, at least a part of the cantilever section 42 can be disposed opposite to the core hole 211. This can not only reasonably arrange the structure of the current collector 40 and improve the space utilization rate, but also facilitate the gas inside the battery core 20 to be transmitted from the core hole 211 to the cantilever section 42, so that stress concentration is formed on the cantilever section 42, which is beneficial to the deformation and folding of the cantilever section 42.

[0083] In one embodiment, the battery can be a quadrangular prism battery. The quadrangular prism battery mainly refers to a battery with a prism shape, but it is not strictly limited whether each side of the prism must be a strict straight line, and the corner between sides does not have to be a right angle and can be a circular arc transition.

[0084] The battery can be a stacked battery, which is not only convenient for grouping but also can be processed into a battery with a longer length. Specifically, the battery core is a stacked battery core, and the battery core has a first electrode plate, a second electrode plate having the opposite electrical property to the first electrode plate, and a separator sheet disposed between the first electrode plate and the second electrode plate that are stacked on each other, so that multiple pairs of first electrode plates and second electrode plates are stacked to form a stacked battery core.

[0085] Alternatively, the battery can be a wound battery, that is, the first electrode plate, the second electrode plate having the opposite electrical property to the first electrode plate, and the separator sheet disposed between the first electrode plate and the second electrode plate are wound to obtain a wound battery core.

[0086] In one embodiment, the first end wall 11 is a cover plate, and the second end wall 12 and the side wall 13 are an integrally formed structure, which not only facilitates the setting of the terminal assembly 30 on the first end wall 11, but also facilitates the formation of the notch 111, thereby improving the manufacturing efficiency of the cylindrical battery.

[0087] The first end wall 11 can be welded to the side wall 13.

[0088] It should be noted that, in some embodiments, it is not excluded that both the first end wall 11 and the second end wall 12 are independent components relative to the side wall 13; alternatively, the first end wall 11 and the side wall 13 are of an integrally formed structure, and the second end wall 12 is a cover plate, that is, the second end wall 12 is an independent component.

[0089] In one embodiment, the notch 111 is disposed around the entire circumference of the pole assembly 30 so that the notch 111 is a circumferentially closed structure, so that after the notch 111 explodes, it can have a relatively large explosion area, thereby improving the pressure relief ability.

[0090] In one embodiment, the notch 111 can be disposed around the pole assembly 30 non-entirely.

[0091] An embodiment of the present invention further provides a battery pack including the above battery.

[0092] The battery of the battery pack according to an embodiment of the present invention includes a battery case 10, a battery cell 20, a pole assembly 30, and a current collector 40. The battery cell 20 is disposed in the battery case 10, the pole assembly 30 is disposed on the first end wall 11 of the battery case 10, the current collector 40 is disposed in the battery case 10, and the pole assembly 30 is electrically connected to the pole ear 22 on the battery cell body 21 through the current collector 40. A notch 111 is disposed on the first end wall 11 around the pole assembly 30 to form an explosion-proof valve. Thus, after the internal pressure of the battery reaches a certain height, the notch 111 can explode, and then the pressure relief of the battery is realized. By making the current collector 40 include a main body section 41 and a cantilever section 42, the cantilever section 42 is connected to the main body section 41, and a weak area is formed between the cantilever section 42 and the main body section 41 so that the cantilever section 42 is flipably disposed relative to the main body section 41. The pole assembly 30 is connected to the cantilever section 42, the pole ear 22 is connected to the main body section 41, and the positive projection of the cantilever section 42 toward the first end wall 11 is at least partially located within the area surrounded by the notch 111. Thus, when the explosion-proof valve is opened, the cantilever section 42 can be deformed and flipped along with the pole assembly 30, thereby reducing the resistance to the explosion-proof valve, increasing the opening height of the explosion-proof valve, enabling the internal air pressure to be quickly discharged, and effectively improving the safe use performance of the battery pack.

[0093] In one embodiment, the battery pack is a battery module or a battery pack. The battery pack includes a plurality of batteries.

[0094] Those skilled in the art will readily conceive of other embodiments of the present disclosure after considering the specification and practicing the utility model creation disclosed herein. The present disclosure is intended to cover any variations, uses, or adaptations of the present utility model, which follow the general principles of the present disclosure and include well-known common general knowledge or conventional technical means in the technical field not disclosed in the present disclosure. The specification and exemplary embodiments are only regarded as exemplary, and the true scope and spirit of the present disclosure are pointed out by the appended claims.

[0095] It should be understood that the present disclosure is not limited to the exact structures already described and shown in the drawings, and various modifications and changes can be made without departing from its scope. The protection scope of the present disclosure is only limited by the appended claims.

Claims

1. A battery, characterized in that: include: A battery housing (10), the battery housing (10) comprising a first end wall (11), a second end wall (12) and a side wall (13), wherein the first end wall (11) and the second end wall (12) are respectively connected to opposite ends of the side wall (13); A battery cell (20), the battery cell (20) being arranged in the battery housing (10), the battery cell (20) comprising a battery cell body (21) and a tab (22), the tab (22) extending from the battery cell body (21); A pole assembly (30), the pole assembly (30) being arranged on the first end wall (11), the first end wall (11) being provided with a notch (111) to form an explosion-proof valve, the notch (111) being arranged around the pole assembly (30); A current collector (40), the current collector (40) being arranged in the battery housing (10) and between the first end wall (11) and the battery cell body (21), the pole assembly (30) being electrically connected to the pole lug (22) via the current collector (40); The current collecting member (40) comprises a main body section (41) and a cantilever section (42); the cantilever section (42) is connected to the main body section (41); a weak area is formed between the cantilever section (42) and the main body section (41), so that the cantilever section (42) can be folded relative to the main body section (41); the pole assembly (30) is directly fixedly electrically connected to the cantilever section (42); the pole ear (22) is directly fixedly electrically connected to the main body section (41); and the orthographic projection of the cantilever section (42) toward the first end wall (11) is at least partially located within the area surrounded by the notch (111).

2. The battery according to claim 1, characterized in that The weakened area includes at least one notch (43).

3. The battery according to claim 2, characterized in that The notches (43) are provided on opposite sides of the cantilever section (42).

4. The battery according to claim 2, characterized in that The depth of the notch (43) is not less than 2 mm.

5. The battery according to claim 2, characterized in that The width between two opposite sides of the notch (43) is in the range of 1 mm to 3 mm.

6. The battery according to any one of claims 1 to 5, characterized in that The main body section (41) is arranged around the cantilever section (42).

7. The battery according to claim 6, characterized in that The main body section (41) is arranged on one side of the cantilever section (42).

8. The battery according to claim 7, characterized in that There are at least two pole tabs (22), and the at least two pole tabs (22) include a positive pole tab and a negative pole tab, and the positive pole tab and the negative pole tab extend from the same side of the battery cell body (21).

9. The battery according to any one of claims 1 to 5, characterized in that A groove (31) is provided on the side of the pole assembly (30) facing the current collecting member (40), and a protrusion (421) is formed on the side of the cantilever section (42) facing the pole assembly (30), and at least a portion of the protrusion (421) is inserted into the groove (31).

10. The battery according to any one of claims 1 to 5, characterized in that The battery is a cylindrical battery.

11. The battery according to claim 10, characterized in that The battery cell body (21) is formed with a winding core hole (211), and along the axial direction of the winding core hole (211), the orthographic projections of the cantilever segment (42) and the winding core hole (211) on the same plane at least partially overlap.

12. The battery according to any one of claims 1 to 5, characterized in that The cantilever section (42) has a length L (unit: mm) from one end away from the main section (41) toward the other end connected to the main section (41), and an area S (unit: mm) enclosed by the notch (111). 2 , the capacity of the battery is A, unit is Ah, and L / (S×A) is 0.0001~0.

003.

13. The battery according to claim 12, characterized in that The wall thickness of the root where the cantilever section (42) is connected to the main section (41) is D. When D≥0.2 mm, L / (S×A) is 0.0002-0.

003.

14. The battery according to any one of claims 1 to 5, characterized in that The cantilever section (42) has a length L in a direction from one end away from the main section (41) toward the other end connected to the main section (41), and an outer contour of the main section (41) away from the cantilever section (42) includes an arc, the radius of the arc is R, and R / L is 1 to 4.

15. The battery according to any one of claims 1 to 5, characterized in that The length of the root where the cantilever section (42) is connected to the main section (41) is H, in mm, the capacity of the battery is A, in Ah, and H / A is 0.1 to 0.

7.

16. The battery according to any one of claims 1 to 5, characterized in that The length of the root where the cantilever section (42) is connected to the main section (41) is H, the area enclosed by the notch (111) is S, and H / S is 0.009 mm -1 ~0.07mm -1 .

17. A battery pack, characterized in that: A battery comprising the battery according to any one of claims 1 to 16.

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