Battery

Abstract

The utility model relates to the technical field of batteries, in particular to a battery which comprises a shell, a roll core, a confluence disc and a cover plate, the roll core and the confluence disc are arranged in the shell, and the confluence disc is arranged at one end of the roll core in the height direction of the roll core; the cover plate is mounted at one opening end of the shell and is close to the convergence disc; the confluence disc and / or the cover plate are / is provided with a supporting protruding part, and the supporting protruding part is supported between the confluence disc and the cover plate, so that a gap is formed between the confluence disc and the cover plate; a first through hole communicated with the gap is formed in the confluence disc, and when the roll core generates gas in a thermal runaway mode, the gas can enter the gap through the first through hole. According to the battery disclosed by the invention, a structure of a connecting sheet is canceled, the confluence plate and the cover plate are connected in a penetration welding manner, meanwhile, the thickness of a welding area of the confluence plate and the cover plate is ingeniously increased, the phenomenon of burning of a roll core diaphragm is avoided, and meanwhile, the thickened welding area can lift the confluence plate to form an exhaust channel, so that the safety of the battery is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery. BACKGROUND

[0002] With the development of society, energy storage systems are paid more and more attention. Large cylindrical batteries are preferred energy storage batteries due to their unique advantages of low internal resistance, high safety, flexibility and the like. Therefore, large cylindrical batteries have been highly concerned. In the current large cylindrical batteries, busbars, i.e. current collecting plates and connecting pieces are often used as the electrical connection structure between the pole posts and the pole tab clusters of the winding core. In the assembly process, the connecting pieces need to be bent, which increases the operation difficulty and complexity, reduces the production efficiency, and the assembly process has many steps, resulting in a low yield. Moreover, the folded connecting pieces are arranged between the busbar and the cover plate, which blocks the exhaust path during thermal runaway, often leading to the battery being unable to quickly exhaust and depressurize, and thus possibly causing the battery to explode. CONTENT OF THE UTILITY MODEL

[0003] The purpose of the present application is to provide a battery, which solves the technical problem in the prior art that the current large cylindrical batteries often use busbars, i.e. current collecting plates and connecting pieces as the electrical connection structure between the pole posts and the pole tab clusters of the winding core, which results in a low assembly efficiency, a low yield and blocks the exhaust, which may cause the battery to explode.

[0004] The present application provides a battery, comprising: an outer shell, a winding core, a busbar and a cover plate; wherein the winding core and the busbar are both arranged in the outer shell, and along the height direction of the winding core, the busbar is arranged at one end of the winding core; the cover plate is installed at an open end of the outer shell and arranged close to the busbar.

[0005] The busbar and / or the cover plate is formed with a support protruding portion, and the support protruding portion is supported between the busbar and the cover plate, so that a gap is formed between the busbar and the cover plate; the busbar is formed with a first through hole communicating with the gap, and when the winding core produces gas during thermal runaway, the gas can enter the gap through the first through hole.

[0006] In the above technical solution, further, the support protruding portion is annular.

[0007] In any of the above technical solutions, further, the support protruding portion is a first welding area of the cover plate and the busbar penetration welding.

[0008] In any of the above technical solutions, further, the support protrusion is formed on the bus bar, and along the height direction of the winding core, the sum of the thickness of the disc body of the bus bar and the support protrusion is h1, and h1 = h0 + k1; wherein h0 is the thickness of the disc body of the bus bar along the height direction of the winding core; k1 is a constant, and the value range of k1 is 0.5-2mm;

[0009] Along the height direction of the winding core, the thickness of the cover plate is h2, and h2 = h1 - k2; wherein k2 is a constant, and the value range of k2 is 0.5-2mm.

[0010] In any of the above technical solutions, further, the bus bar is formed with a second welding area for welding with the tab cluster of the winding core, and the second welding area is away from the first welding area.

[0011] In any of the above technical solutions, further, the number of the second welding areas is multiple, and the multiple second welding areas are arranged in a ring array with the center of the bus bar as the center.

[0012] In any of the above technical solutions, further, the center of the bus bar is formed with a second through hole, and the second through hole respectively communicates with the gap and the center hole of the winding core.

[0013] In any of the above technical solutions, further, the cover plate is a bottom cover plate, and is installed at the bottom opening end of the shell; the battery further comprises a top cover plate assembly, and the top cover plate assembly is installed at the top opening end of the shell, and the center hole of the winding core communicates with an explosion-proof valve of the top cover plate assembly.

[0014] In any of the above technical solutions, further, the radius of the second through hole is r1, the radius of the center hole of the winding core is r0, and r1 = k3 * r0, wherein k3 is a constant, and the value range of k3 is 50%-90%.

[0015] In any of the above technical solutions, further, the cover plate is a top cover plate, and is installed at the top opening end of the shell; the battery further comprises an explosion-proof valve, and the explosion-proof valve is installed in the mounting through hole of the top cover plate, and the gap communicates with the explosion-proof valve; or

[0016] The battery further comprises an explosion-proof valve, and the explosion-proof valve is installed in the mounting through hole of the side wall of the shell, and the gap communicates with the explosion-proof valve.

[0017] In any of the above technical solutions, further, the number of the first through holes is multiple, and the multiple first through holes are arranged in a ring array with the center of the busbar as the center, and the first through holes in any adjacent two ring arrays are staggered.

[0018] In any of the above technical solutions, further, the radius of the first through hole is r2, and the value of r2 is 0.5-2mm.

[0019] Compared with the prior art, the application has the following beneficial effects:

[0020] The application changes the conventional connection mode of the busbar and the cover plate of the cylindrical battery, cancels the structure of the connecting sheet, connects the busbar and the cover plate by means of penetration welding, and increases the thickness of the welding area of the busbar and the cover plate by means of the principle of penetration welding. In the process of welding the busbar and the bottom cover plate, the phenomenon of burning of the core separator due to penetration of the busbar does not occur, and the thickened welding area can lift the busbar to realize the existence of a gap between the busbar and the bottom cover plate, thereby increasing the space for storing electrolyte in the battery. When the battery is in thermal runaway, the gas generated can be discharged from the core through the through holes and the center hole of the busbar to the empty area, and finally discharged to the outside of the battery through the explosion-proof valve, thereby increasing the safety of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the specific embodiments of the application or the technical solutions in the prior art, the drawings needed in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0022] Figure 1 The structural schematic diagram of the busbar provided by the embodiments of the application is shown in the figure.

[0023] Figure 2 The assembly drawing of the busbar and the cover plate provided by the embodiments of the application is shown in the figure.

[0024] Figure 3 The structural schematic diagram of the battery provided by the embodiments of the application is shown in the figure.

[0025] REFERENCE SIGNS:

[0026] 1-outer shell, 2-core, 21-center hole, 3-busbar, 31-supporting protrusion, 32-first through hole, 33-first welding area, 34-second welding area, 35-second through hole, 4-cover plate, 5-gap, 6-top cover plate assembly. DETAILED DESCRIPTION

[0027] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application.

[0028] The components of the embodiments of the present application generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application.

[0029] Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present application.

[0030] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0031] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0032] The following will be described with reference to Figures 1 to 3 The battery according to some embodiments of the present application is described.

[0033] Referring to Figures 1 to 3 As shown in the drawings, the embodiments of the present application provide a battery, comprising: a shell 1, a winding core 2, a bus bar 3 and a cover plate 4; wherein the winding core 2 and the bus bar 3 are both arranged in the shell 1, and along the height direction of the winding core 2, the bus bar 3 is arranged at one end of the winding core 2; the cover plate 4 is mounted at an open end of the shell 1, and is arranged close to the bus bar 3;

[0034] The busbar 3 is formed with a supporting protrusion 31, and the supporting protrusion 31 is supported between the busbar 3 and the cover plate 4, so that a gap 5 is formed between the busbar 3 and the cover plate 4; the busbar 3 is formed with a first through hole 32 which is communicated with the gap 5, and when the core 2 produces gas due to thermal runaway, the gas can enter the gap 5 through the first through hole 32.

[0035] Further preferably, the center of the busbar 3 is formed with a second through hole 35 which is respectively communicated with the gap 5 and the center hole 21 of the core 2;

[0036] The cover plate 4 is a bottom cover plate and is installed at the bottom opening end of the shell 1; the battery further comprises a top cover plate assembly 6 which is installed at the top opening end of the shell 1, and the center hole 21 of the core 2 is communicated with an explosion-proof valve of the top cover plate assembly 6.

[0037] According to the above-described structure, the battery provided by the application removes the structure of the connecting sheet, directly connects the busbar 3 and the cover plate 4, and sets the supporting protrusion 31 between the busbar 3 and the cover plate 4, so that the busbar 3 and the cover plate 4 are spaced apart, that is, a gap 5 is formed therebetween, which can be used as an exhaust passage, and then when the battery produces thermal runaway, the gas in the battery enters the gap 5 through the first through hole 32, and then enters the center hole 21 of the core 2 through the gap 5, and then passes through the center hole 21 of the core 2 to reach the explosion-proof valve of the top cover plate assembly 6, and is discharged and relieved through the explosion-proof valve, so as to reduce the gas pressure in the core 2, avoid the expansion of the core 2 due to the excessive gas pressure, and prevent the battery shell from exploding and exploding, so as to ensure the safety and reliability of the battery in use, and the gap 5 between the busbar 3 and the cover plate 4 increases the storage space of the electrolyte, which plays a role in supplementing the electrolyte, so as to ensure the use performance of the battery. In addition, the structure of the connecting sheet is removed in the application, which greatly improves the space utilization, and directly connects the busbar 3 and the cover plate 4, and the cover plate 4 is used as an output, so that the structure of the pole is not required, the investment in parts is saved, and the cost is reduced.

[0038] Further preferably, the supporting protrusion 31 and the disc body of the busbar 3 are in an integral structure, of course, not limited to this, but can also be in a split structure which is assembled together later, and the specific selection is based on the actual needs.

[0039] Further preferably, the extension directions of the first through hole 32, the second through hole 35 and the center hole 21 of the core 2 are the same as the height direction of the core 2. Of course, not limited to this, the extension directions of the first through hole 32 and the second through hole 35 can also form a certain angle, for example, an acute angle, with the height direction of the core 2, and the specific design is based on the actual needs.

[0040] It should be noted that: not only limited to the aforementioned cover plate 4 as the bottom cover plate is used, and also for the shell 1 is equipped with top cover plate assembly 6, and on the top cover plate assembly 6 set up the structure of the explosion-proof valve, also can use other structures, for example: the first, the aforementioned cover plate 4 can also be used as the top cover plate, and can be installed on the cover plate 4 explosion-proof valve, also can realize exhaust, pressure relief, and only need to be equipped with no explosion-proof valve bottom cover plate 4 assembly can be, and the center hole 21 on the bus bar 3 is the second through hole 35 can be optional, according to the actual need to choose.

[0041] The second, the aforementioned cover plate 4 is still used as the bottom cover plate, while the explosion-proof valve is arranged on the side wall of the shell 1, and the explosion-proof valve is in communication with the gap 5, so that the exhaust can also be realized, and the center hole 21 on the bus bar 3 is the second through hole 35 can be optional, according to the actual need to choose, and the explosion-proof valve on the top cover plate assembly 6 can also be optional, according to the actual need to choose.

[0042] In addition, it should be noted that: not only limited to the above-mentioned bus bar 3 is formed with support protruding part 31, but also can use other structures, for example: remove the support protruding part 31 on the bus bar 3, but the support protruding part 31 is arranged on the cover plate 4, or the support protruding part 31 is arranged on the bus bar 3 and the cover plate 4 at the same time, according to the actual need to choose. In this embodiment, preferably, as shown in Figures 1 to 3 The support protruding part 31 is annular.

[0043] In addition, it should be noted that: the battery provided in the embodiment is a cylindrical battery, of course, not only limited to this, but also can be other shape of the battery, for example, cuboid or other shape of the battery.

[0044] According to the structure described above, the support protruding part 31 is designed as an annular structure, and the cover plate 4 and the bus bar 3 are spaced apart along the entire circumference, the exhaust passage is increased, and the exhaust effect can be further improved.

[0045] It should be noted that: the support protruding part 31 is not only limited to the annular structure, the support protruding part 31 can also adopt other structures, for example: the support protruding part 31 can also be part of the annular structure, that is, a fan ring shaped block, and a plurality of support protruding parts 31 are sequentially and spaced apart along the circumference of the bus bar 3, which can also play a role in overall support.

[0046] In this embodiment, preferably, as shown in Figure 1 And Figure 2 The support protruding part 31 is the first welding area 33 of the cover plate 4 and the bus bar 3.

[0047] According to the above-described structure, the support protruding part 31 is used as the penetration welding area, thereby increasing the thickness of the welding area of the busbar 3 and the cover plate 4, and the penetration welding of the busbar 3 does not occur during the welding of the busbar 3 and the cover plate 4, and the phenomenon of burning of the diaphragm of the winding core 2 is avoided, and the yield of the battery is greatly improved.

[0048] It should be noted that the height of the busbar 3, the cover plate 4 and the winding core 2 is the same, and along the height direction of the winding core 2, the annular area of the cover plate 4 corresponding to the support protruding part 31 is also a welding area and participates in the penetration welding, and even along the height direction of the winding core 2, the annular area of the disc body of the busbar 3 corresponding to the support protruding part 31 can also be used as the penetration welding area, and of course, the penetration welding depth is selected according to actual needs, and it is not necessary to reach the disc body of the busbar 3.

[0049] In this embodiment, preferably, as shown in Figure 2 the support protruding part 31 is formed on the busbar 3, and along the height direction of the winding core 2, the sum of the thickness of the support protruding part 31 and the disc body of the busbar 3 is h1, and h1 = h0 + k1; wherein h0 is the thickness of the disc body of the busbar 3 along the height direction of the winding core 2; k1 is a constant, and the value range of k1 is 0.5-2mm, that is, 0.5mm≤k1≤2mm, and of course, the value range of k1 is not limited to the above, for example, k1 can also be less than 0.5mm or greater than 2mm, and the specific value is selected according to actual needs.

[0050] According to the above-described structure, since the support protruding part 31 is arranged on the busbar 3, the total thickness of the welding area of the busbar 3 and the cover plate 4 is greater than the thickness of the disc body of the busbar 3, and the above calculation formula can be used as a guide for later production, and is more standardized and normalized.

[0051] Of course, the calculation formula of the sum h1 of the thickness of the support protruding part 31 and the disc body of the busbar 3 is not limited to the above, and can be designed according to actual needs.

[0052] In this embodiment, preferably, as shown in Figure 2 along the height direction of the winding core 2, the thickness of the cover plate 4 is h2, and h2 = h1 - k2; wherein k2 is a constant, and the value range of k2 is 0.5-2mm, that is, 0.5mm≤k2≤2mm, and of course, the value range of k2 is not limited to the above, for example, k2 can also be less than 0.5mm or greater than 2mm, and the specific value is selected according to actual needs; and h2 is the thickness of the cover plate 4.

[0053] According to the above-described structure, the thickness of the cover plate 4 is less than the thickness of the welding area on the busbar 3, facilitating penetration welding, and the above-described calculation formula can be used as a guide for later production, making it more standardized and normative.

[0054] Of course, the calculation formula of the thickness h2 of the cover plate 4 is not limited to the above, but can also be designed according to actual needs.

[0055] In this embodiment, preferably, as shown in Figure 1 The busbar 3 is formed with a second welding area 34 for welding with the tab cluster of the core 2, and the second welding area 34 is kept away from the first welding area 33.

[0056] According to the above-described structure, the busbar 3 and the core 2 are also connected by welding, such as penetration welding, which is more convenient to operate, and the structure of the welding site is more stable and firm.

[0057] In this embodiment, preferably, as shown in Figure 1 The number of second welding areas 34 is multiple, and the multiple second welding areas 34 are arranged in a ring array structure with the center of the busbar 3 as the center.

[0058] According to the above-described structure, the multiple second welding areas 34 are arranged in a ring array structure, making the welding area distribution more uniform, and making the structure of the busbar 3 and the cover plate 4 after welding more stable and firm.

[0059] Further, preferably, the multiple second welding areas 34 form two ring array structures, of course, not limited to this, but also can adopt one ring array structure or a ring array structure with a number greater than two, which is selected according to actual needs.

[0060] In this embodiment, preferably, as shown in Figures 1 to 3 The center of the busbar 3 is formed with a center hole 21.

[0061] According to the above-described structure, the center hole 21 is provided in the center of the busbar 3, corresponding to the center hole 21 of the core 2, the center hole 21 on the busbar 3 can be used as a liquid injection channel to speed up the liquid injection speed, and can also be used as an exhaust channel when the battery cell is in thermal runaway.

[0062] In this embodiment, preferably, as shown in Figure 1 and Figure 3 The radius of the center hole 21 is r1, the radius of the center hole 21 of the core 2 is r0, and r1=k3×r0, where k3 is a constant, and the value range of k3 is 50%-90%, that is, 50%≤k3≤90%, of course, the value range of k3 is not limited to the above, for example: k3<50% or k3>90%, which is selected according to actual needs.

[0063] Based on the structure described above, the center hole 21 on the manifold 3 is smaller than the center hole 21 on the core 2, so that the size of the center hole 21 on the manifold 3 is not too large, ensuring that there is enough area to design the welding area and the through hole area.

[0064] Of course, the formula for calculating the radius r1 of the center hole 21 is not limited to the above, and can also be designed according to actual needs.

[0065] In this embodiment, preferably, as follows: Figure 1 As shown, multiple first through holes 32 are arranged in a ring array with the center of the manifold 3 as the center, and the first through holes 32 in any two adjacent ring arrays are staggered.

[0066] As can be seen from the structure described above, this arrayed and staggered annular array structure makes the multiple first through holes 32 more evenly distributed, ensuring the uniformity of liquid injection and venting.

[0067] Furthermore, preferably, the multiple first through holes 32 form four annular array structures. Of course, it is not limited to this. One annular array, two annular arrays, three annular arrays, or more than four annular array structures can also be used, depending on the actual needs.

[0068] It should be noted that the arrangement of the multiple first through holes 32 is not limited to the above, and can be distributed arbitrarily.

[0069] In this embodiment, preferably, as follows: Figure 1 As shown, the radius of the through hole is r2, and the value of r2 is 0.5-2mm, that is, 0.5mm≤r2≤2mm.

[0070] Based on the structure described above, the range of possible values ​​for the radius of the through hole is provided, thus guiding subsequent production and making it more standardized and regulated. Of course, the range of possible values ​​for the radius of the through hole is not limited to the above; for example, r2 < 0.5 mm or r2 > 0.5 mm can also be chosen according to actual needs.

[0071] In summary, the battery provided in this application has the following structure and advantages:

[0072] The application changes the connection mode of the busbar 3 and the cover plate 4 of the cylindrical battery, cancels the structure of the connecting piece, connects the busbar 3 and the cover plate 4 by means of penetration welding, increases the thickness of the welding area of the busbar 3 and the cover plate 4 by the principle of penetration welding, and does not cause the phenomenon of burning of the diaphragm of the winding core 2 in the process of welding the busbar 3 and the bottom cover plate 4. The thickened welding area can lift the busbar 3, realize the gap 5 between the busbar 3 and the bottom cover plate 4, increase the space for storing electrolyte of the battery, and when the battery occurs thermal runaway, the gas generated can be discharged from the winding core 2 through the through hole on the busbar 3 and the center hole 21, and then discharged to the outside of the battery through the explosion-proof valve, thereby increasing the safety of the battery.

[0073] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the application, and not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application.

Claims

1. A battery, characterized by, The battery comprises a shell, a winding core, a busbar and a cover plate; the winding core and the busbar are arranged in the shell, and the busbar is arranged at one end of the winding core along the height direction of the winding core; the cover plate is arranged at an open end of the shell and close to the busbar; The busbar and / or the cover plate are formed with a support protrusion, and the support protrusion is supported between the busbar and the cover plate to form a gap between the busbar and the cover plate; the busbar is formed with a first through hole communicating with the gap, and when the winding core produces gas due to thermal runaway, the gas can enter the gap through the first through hole. The support protrusion is annular.

2. The battery of claim 1, wherein, The support protrusion is a first welding area of the cover plate and the busbar.

3. The battery of claim 1, wherein, The support protrusion is formed on the busbar, and the sum of the thickness of the support protrusion and the thickness of the disc body of the busbar along the height direction of the winding core is h1, and h1=h0+k1; wherein h0 is the thickness of the disc body of the busbar along the height direction of the winding core; k1 is a constant, and the value of k1 is 0.5-2mm; 4. The battery of claim 3, wherein, The thickness of the cover plate along the height direction of the winding core is h2, and h2=h1-k2; wherein k2 is a constant, and the value of k2 is 0.5-2mm. The busbar is formed with a second welding area welded with the tab cluster of the winding core, and the second welding area avoids the first welding area.

5. The battery of claim 3, wherein, The number of the second welding area is multiple, and multiple second welding areas are arranged in a ring array with the center of the busbar as the center.

6. The battery of claim 5, wherein, The center of the busbar is formed with a second through hole, and the second through hole respectively communicates with the gap and the center hole of the winding core.

7. The battery of claim 1, wherein, The cover plate is a bottom cover plate, and is arranged at the bottom opening end of the shell; the battery further comprises a top cover plate assembly, and the top cover plate assembly is arranged at the top opening end of the shell, and the center hole of the winding core communicates with an explosion-proof valve of the top cover plate assembly; and / or 8. The battery of claim 7, wherein, The radius of the second through hole is r1, the radius of the center hole of the winding core is r0, and r1=k3*r0, wherein k3 is a constant, and the value of k3 is 50%-90%. The cover plate is a top cover plate, and is arranged at the top opening end of the shell; the battery further comprises an explosion-proof valve, and the explosion-proof valve is arranged in the mounting through hole of the top cover plate, and the gap communicates with the explosion-proof valve; or 9. The battery of claim 1, wherein, The battery further comprises an explosion-proof valve, and the explosion-proof valve is arranged in the mounting through hole of the side wall of the shell, and the gap communicates with the explosion-proof valve. The number of the first through hole is multiple, and multiple first through holes are arranged in a ring array with the center of the busbar as the center, and the first through holes in any adjacent two ring arrays are staggered; and / or 10. The battery of any one of claims 1-9, wherein, The radius of the first through hole is r2, and the value of r2 is 0.5-2mm. ​

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