Battery

Abstract

The utility model relates to the technical field of new energy batteries, and discloses a battery, the welding effect consistency of a tab assembly and a current collecting piece of the battery is better, the overcurrent capacity between the tab assembly and a current collecting plate can be ensured, and the overall performance of the battery is further improved. The battery provided by the utility model comprises a tab assembly and a current collecting piece, the tab assembly comprises a first connecting part and a second connecting part, and the thickness of the first connecting part is smaller than that of the second connecting part. The current collecting piece comprises a first connecting area and a second connecting area which are connected, and the thickness of the first connecting area is larger than that of the second connecting area. The first connecting part is electrically connected with the first connecting area, and the second connecting part is electrically connected with the second connecting area.

Description

Technical Field

[0001] This utility model relates to the field of new energy battery technology, specifically to a battery. Background Technology

[0002] Cylindrical batteries are widely used due to their high capacity, long cycle life, and wide operating temperature range. In existing cylindrical batteries, after the core is wound and formed, the tab assembly is led out from the end of the core and bent. Because the thickness of the bent tab assembly is uneven, the welding effect between the tab assembly and the current collector at different locations is inconsistent, easily leading to problems such as incomplete soldering and poor welding, affecting the current carrying capacity and consequently the overall performance of the battery. Utility Model Content

[0003] In view of this, the present invention provides a battery to solve the problem of inconsistent welding effect between the electrode tab assembly and the current collector in existing batteries, which affects the current carrying capacity.

[0004] In a first aspect, this utility model provides a battery, comprising:

[0005] The electrode assembly includes a first connecting portion and a second connecting portion, wherein the thickness of the first connecting portion is less than the thickness of the second connecting portion;

[0006] A current collector includes a first connection area and a second connection area connected to each other. The thickness of the first connection area is greater than the thickness of the second connection area. The first connection part is electrically connected to the first connection area, and the second connection part is electrically connected to the second connection area.

[0007] Beneficial Effects: The battery of this invention includes a tab assembly comprising a first connecting portion and a second connecting portion, with the thicknesses of the first and second connecting portions being different, the first connecting portion being thinner than the second connecting portion. Correspondingly, the current collector includes a first connecting region and a second connecting region connected together, with the thickness of the first connecting region being greater than the thickness of the second connecting region. The thinner first connecting portion is electrically connected to the thicker first connecting region, and the thicker second connecting portion is electrically connected to the thinner second connecting region. When the first connecting portion is electrically connected to the first connecting region, due to the thinner thickness of the first connecting portion, the welding strength between them is higher, resulting in a better welding effect. Simultaneously, due to the larger thickness of the first connecting region, the welding process between the two is less likely to melt through and damage the battery core, improving the safety of the welding operation and reducing the welding difficulty. Conversely, when the second connecting portion is electrically connected to the second connecting region, due to the thicker thickness of the second connecting portion, reducing the thickness of the second connecting region increases the welding strength between the two, reducing the occurrence of incomplete welds and poor welding phenomena. This results in better consistency in the welding effect between the tab assembly and the current collector, ensuring the current carrying capacity between the tab assembly and the current collector, thereby improving the overall performance of the battery. Attached Figure Description

[0008] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used 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 this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0009] Figure 1 This is a schematic diagram of the battery of this utility model;

[0010] Figure 2 This is a perspective view of the winding core in the battery of this utility model;

[0011] Figure 3 This is a top view of the winding core in the battery of this utility model;

[0012] Figure 4 This is a top-view perspective view of the current collector in the battery of this utility model;

[0013] Figure 5 This is a perspective view of the current collector in the battery of this utility model from a bottom angle;

[0014] Figure 6 This is a top view of the current collector in the battery of this utility model;

[0015] Figure 7 This is a cross-sectional view of the current collector and the tab assembly in the battery of this utility model after being electrically connected;

[0016] Figure 8 for Figure 7 An enlarged schematic diagram of part A in the middle.

[0017] Explanation of reference numerals in the attached figures:

[0018] 1. Electrode assembly; 101. First connecting part; 102. Second connecting part;

[0019] 2. Current collector; 201. First connecting area; 202. Second connecting area; 203. Groove; 204. Upper surface of current collector; 205. Lower surface of current collector;

[0020] 3. Shell;

[0021] 4. Core; 401. Core hole. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0023] Currently, after the cylindrical battery core is wound and formed, the tab assembly is led out from the end of the core and bent towards the core hole. After bending, the portion of the tab assembly near the core hole and the inner wall of the battery casing is thinner, while the middle portion is thicker. When welding the tab assembly to the current collector, although the weld strength is high when the thinner portion of the tab assembly is welded to the current collector, it is easy to melt through and damage the core, making the welding operation more difficult. When welding the thicker portion of the tab assembly to the current collector, it is prone to incomplete welds and lower weld strength. This results in poor consistency in the welding effect between the tab assembly and the current collector, affecting the current carrying capacity between the tab assembly and the current collector, and adversely affecting the overall battery performance.

[0024] Based on this, the present invention provides a battery with good consistency in the welding effect between the tab assembly and the current collector.

[0025] The following is combined Figures 1 to 8 This describes an embodiment of the battery of the present invention.

[0026] According to an embodiment of the present invention, a battery is provided, comprising: a tab assembly 1 and a current collector 2. The tab assembly 1 includes a first connecting portion 101 and a second connecting portion 102, wherein the thickness of the first connecting portion 101 is less than the thickness of the second connecting portion 102. The current collector 2 includes a first connecting region 201 and a second connecting region 202 connected to each other, wherein the thickness of the first connecting region 201 is greater than the thickness of the second connecting region 202; the first connecting portion 101 is electrically connected to the first connecting region 201, and the second connecting portion 102 is electrically connected to the second connecting region 202.

[0027] In this type of battery, the thicknesses of the first connecting portion 101 and the second connecting portion 102 of the tab assembly 1 are not the same, with the thickness of the first connecting portion 101 being less than the thickness of the second connecting portion 102. Correspondingly, the thickness of the first connecting region 201 of the current collector 2 is greater than the thickness of the second connecting region 202. The thinner first connecting portion 101 is electrically connected to the thicker first connecting region 201, and the thicker second connecting portion 102 is electrically connected to the thinner second connecting region 202. When the first connecting part 101 is electrically connected to the first connecting area 201, the welding strength between the first connecting part 101 and the first connecting area 201 is high due to the smaller thickness of the first connecting part 101, resulting in a better welding effect. At the same time, due to the larger thickness of the first connecting area 201, the welding process between the two is less likely to melt through and damage the battery core, thus improving the safety of the welding operation and reducing the welding difficulty. When the second connecting part 102 is electrically connected to the second connecting area 202, the welding strength between the second connecting part 102 and the second connecting area 202 is improved by reducing the thickness of the second connecting area 202, thereby reducing the occurrence of incomplete welding and poor welding phenomena. This results in better consistency in the welding effect between the tab assembly 1 and the current collector 2, ensuring the current carrying capacity between the tab assembly 1 and the current collector 2, and thus improving the overall performance of the battery.

[0028] The battery in this embodiment is specifically a cylindrical battery, with the positive and negative terminals leading out on the same side. The battery includes a casing 3, which is a cylindrical structure and is typically made of a metal material (such as steel or aluminum). An accommodating space is formed inside the casing 3, within which the tab assembly 1 and the current collector 2 are disposed.

[0029] It should be noted that in this embodiment, the battery is a cylindrical battery, and the height direction of the battery is its axial direction, such as... Figure 1 The direction indicated by the middle arrow y, perpendicular to the battery's height, is the battery's radial direction. Figure 1 , Figure 3 , Figure 6 The direction indicated by the middle arrow x.

[0030] In this embodiment, the battery also includes a winding core 4, or a battery cell, which is disposed within the receiving space of the housing 3. The center of the winding core 4 is the winding core hole 401. Figures 2-3 As shown, the tab assembly 1 extends from the end of the winding core 4. The tab assembly 1 includes a positive tab assembly and a negative tab assembly, which extend from the same end of the winding core 4 to achieve the same-side lead-out of the positive and negative electrodes of the battery. This cylindrical battery with the positive and negative electrodes led out on the same side has a compact structure and small size.

[0031] like Figures 2-3As shown, in this embodiment, two tab assemblies 1 extend from the upper end of the winding core 4. The two tab assemblies 1 are a positive tab assembly and a negative tab assembly, respectively. Furthermore, to accommodate the structure of a cylindrical battery, the two tab assemblies 1 are arranged in a fan-shaped configuration. Optionally, the two fan-shaped tab assemblies 1 are concentric, with the center being the winding core hole 401. For ease of structural arrangement, the two tab assemblies 1 are arranged symmetrically with respect to the battery's axial direction.

[0032] The two tab assemblies 1 can have the same or different structures. In this embodiment, we take the two tab assemblies 1 having the same structure as an example.

[0033] The tab assembly 1 is used to draw current from inside the winding core 4. The tab assembly 1 includes multiple tabs. After being drawn out from the end of the winding core 4, the tab assembly 1 is bent inward, that is, bent towards the winding core hole 401. Since the tab assembly 1 is formed by bending and stacking multiple tabs, and the distribution of each tab is different, the thickness of the tab assembly 1 after bending inward is uneven, that is, some parts of the tab assembly 1 are thicker and some parts are thinner. In this embodiment, the tab assembly 1 includes a first connecting part 101 and a second connecting part 102, and the thickness of the first connecting part 101 is smaller than the thickness of the second connecting part 102.

[0034] The current collector 2 is electrically connected to the tab assembly 1 to achieve current transmission. The current collector 2 is positioned near the end of the core 4 leading out from the tab assembly 1 to facilitate connection between the tab assembly 1 and the current collector 2. In this embodiment, the current collector 2 is specifically a current collector disk.

[0035] The thickness of the current collector 2 is not uniform, but is matched with different thickness portions of the tab assembly 1. In this embodiment, the current collector 2 includes a first connection area 201 and a second connection area 202. The thicknesses of the first connection area 201 and the second connection area 202 are different. Specifically, the thickness of the first connection area 201 is greater than the thickness of the second connection area 202. The first connection part 101 is electrically connected to the first connection area 201, and the second connection part 102 is electrically connected to the second connection area 202. In this embodiment, the above-mentioned electrical connection is implemented by welding.

[0036] Optionally, the first connection area 201 is positioned corresponding to the first connection portion 101, and the second connection area 202 is positioned corresponding to the second connection portion 102, to facilitate welding operations.

[0037] By setting the current collector 2 as a structural component with inconsistent thickness, and connecting the different thickness areas of the current collector 2 to the corresponding thickness portions of the tab assembly 1, i.e., the first connecting part 101 is electrically connected to the first connecting area 201, and the second connecting part 102 is electrically connected to the second connecting area 202, it is achieved that when the first connecting part 101 is electrically connected to the first connecting area 201, due to the smaller thickness of the first connecting part 101, its welding strength with the first connecting area 201 is higher, resulting in a better welding effect. Simultaneously, due to the larger thickness of the first connecting area 201, the welding process between the two is not easily compromised. Easily melts and damages the battery core, improving the safety and reducing the difficulty of welding operations; when the second connecting part 102 is electrically connected to the second connecting area 202, since the second connecting part 102 is thicker, the thickness of the second connecting area 202 is reduced to improve the welding strength between the second connecting part 102 and the second connecting area 202, reducing the occurrence of incomplete welding and poor welding phenomena, thereby making the welding effect of the tab assembly 1 and the current collector 2 more consistent, ensuring the current carrying capacity between the tab assembly 1 and the current collector 2, and thus improving the overall performance of the battery.

[0038] Furthermore, on the side of the current collector 2 facing away from the tab assembly 1, along the height direction of the battery, the first connection area 201 is higher than the second connection area 202.

[0039] Because the thickness of the first connection region 201 of the current collector 2 is greater than that of the second connection region 202, the thickness of the first connection region 201 is larger than that of the second connection region 202 in the height direction of the battery. In this embodiment, the side of the current collector 2 facing the tab assembly 1 is planar, such as... Figure 5 As shown, the lower surface of the current collector 2 faces the tab assembly 1, and the lower surface of the current collector 2 is planar corresponding to the position of the tab assembly 1. At this time, the height difference between the first connection area 201 and the second connection area 202 of the current collector 2 is entirely on the side of the current collector 2 facing away from the tab assembly 1. That is, on the side of the current collector 2 facing away from the tab assembly 1, along the height direction of the battery, the first connection area 201 is higher than the second connection area 202. This arrangement does not affect the welding operation between the current collector 2 and the tab assembly 1. When welding the current collector 2 and the tab assembly 1, the surface of the current collector 2 relative to the tab assembly 1 is planar, that is, the lower surface 205 of the current collector is planar, resulting in a larger contact area between the current collector 2 and the tab assembly 1. The current collector 2 can flatten the tab assembly 1, facilitating the welding operation between the current collector 2 and the tab assembly 1.

[0040] In other embodiments, on the side of the current collector 2 facing away from the tab assembly 1, along the height direction of the battery, the first connection area 201 is higher than the second connection area 202. At the same time, the side of the current collector 2 facing the tab assembly 1 is not flat and also has a height difference. In this case, the lower surface of the current collector 2 is similar to being fastened to the tab assembly 1, which can also realize the welding operation between the current collector 2 and the tab assembly 1.

[0041] Furthermore, the battery also includes a housing 3, a current collector 2 and a tab assembly 1 disposed inside the housing 3, a first connection portion 101 disposed near the inner wall of the housing 3, and the thickness of the first connection area 201 is in the range of 0.2mm-0.8mm.

[0042] In this embodiment, the battery includes a housing 3. A thinner first connecting portion 101 on the tab assembly 1 is disposed near the inner wall of the housing 3. At this location, the first connecting portion 101 is positioned at the edge of the cylindrical battery, meaning the tab assembly 1 is thinner at its outer edge. After the first connecting portion 101 at this location is welded to the first connecting area 201, it is susceptible to external impact, which can affect the welding strength between the first connecting portion 101 and the current collector 2, thus affecting the current flow between the tab assembly 1 and the current collector 2. Therefore, increasing the thickness of the first connecting area 201 helps resist external impact and ensures the welding strength between the first connecting portion 101 and the current collector 2. In this embodiment, the thickness of the first connecting area 201 ranges from 0.2mm to 0.8mm.

[0043] If the thickness of the first connecting area 201 is too small, the protection effect on the core 4 will be poor when the first connecting part 101 and the first connecting area 201 are welded. The core 4 will still be easily melted through and damaged, resulting in poor welding safety and greater welding difficulty. Moreover, after the first connecting part 101 and the first connecting area 201 are welded, the weld strength between them is insufficient to resist external impact, affecting the current carrying capacity between them. On the other hand, if the thickness of the first connecting area 201 is too large, problems such as incomplete welding and poor welding are likely to occur when the first connecting part 101 and the first connecting area 201 are welded. This will affect the welding strength and welding effect between the first connecting part 101 and the first connecting area 201. If subjected to external impact, it is more likely to cause the weld to break and detach, affecting the current carrying capacity between them.

[0044] In this embodiment, the thickness of the first connection area 201 is in the range of 0.2mm-0.8mm. Within the above range, the thickness of the first connection area 201 is neither too small nor too large. When the first connection part 101 and the first connection area 201 are welded, it is not easy to melt through and damage the core 4. This reduces the welding difficulty, improves the safety of the welding operation, and improves the welding quality. At the same time, the welding strength between the two is high and it is not easily affected by external impact, thereby ensuring the current carrying capacity of the first connection part 101 and the first connection area 201 and improving the overall performance of the battery.

[0045] For example, the thickness of the first connection area 201 can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, or 0.8mm.

[0046] Furthermore, the battery also includes a winding core 4, with a tab assembly 1 extending from the end of the winding core 4. A first connecting portion 101 is disposed near the winding core hole 401 of the winding core 4, and the thickness of the first connecting area 201 ranges from 0.2mm to 0.8mm.

[0047] In this embodiment, the battery also includes a winding core 4. The battery is a cylindrical battery, and the winding core 4 is also cylindrical in shape. The center of the winding core 4 is the winding core hole 401. Figure 2 and Figure 3 As shown, the first connecting portion 101, which has a relatively small thickness, is located near the core hole 401 on the tab assembly 1. When the first connecting portion 101 at this location is welded to the first connecting area 201, it is more likely to melt through and damage the core 4, making welding more difficult and resulting in poor safety during the welding operation. Therefore, the thickness of the first connecting area 201 is increased, and the thickness of the first connecting area 201 ranges from 0.2mm to 0.8mm.

[0048] If the thickness of the first connecting area 201 is too small, the protection effect on the core 4 will be poor when welding the first connecting part 101 to the first connecting area 201. The core 4 will still be easily damaged by melting through, making welding difficult and reducing the safety of the welding operation. Conversely, if the thickness of the first connecting area 201 is too large, problems such as incomplete welding and poor welding are likely to occur when welding the first connecting part 101 to the first connecting area 201, affecting the welding strength and effect between the two, and consequently impacting their current-carrying capacity.

[0049] In this embodiment, the thickness of the first connection area 201 is in the range of 0.2mm-0.8mm. Within the above range, the thickness of the first connection area 201 is neither too small nor too large. When the first connection part 101 and the first connection area 201 are welded, it is not easy to melt through and damage the core 4. This reduces the welding difficulty, improves the safety of the welding operation, and also improves the welding quality. At the same time, the welding strength between the two is high, thereby ensuring the current carrying capacity of the first connection part 101 and the first connection area 201 and improving the overall performance of the battery.

[0050] For example, the thickness of the first connection area 201 can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, or 0.8mm.

[0051] Furthermore, the end of the first connecting portion 101 is bent away from the core hole 401, and the thickness of the first connecting area 201 is in the range of 0.2mm-0.5mm.

[0052] In this embodiment, after the tab assembly 1 is led out from the end of the core 4, the tab assembly 1 is bent towards the core hole 401. At this time, the part of the tab assembly 1 near the core hole 401 is thinner, that is, the first connecting part 101 is located near the core hole 401. At this time, the ends of the tabs of the first connecting part 101 are all located near the core hole 401. If the first connecting part 101 is directly welded to the first connecting area 201, it is easy to melt through and damage the core 4.

[0053] Therefore, in this embodiment, the end of the first connecting portion 101 is bent away from the core hole 401. That is, all the ends of the tabs of the first connecting portion 101 are bent again and away from the core hole 401, so that the end of the first connecting portion 101 is away from the core hole 401. At the same time, the bending of the tab ends can also thicken the first connecting portion 101. At this time, the thickness of the first connecting area 201 can be appropriately reduced. The thickness of the first connecting area 201 is in the range of 0.2mm-0.5mm. At this time, it can still be ensured that the core 4 will not be melted through and damaged when the first connecting portion 101 and the first connecting area 201 are welded, thus ensuring welding safety, reducing the difficulty of welding operation, and reducing manufacturing costs.

[0054] For example, the thickness of the first connection area 201 can be 0.2mm, 0.3mm, 0.4mm, or 0.5mm.

[0055] Furthermore, the tab assembly 1 includes two first connecting portions 101 and a second connecting portion 102, with the second connecting portion 102 located between the two first connecting portions 101.

[0056] like Figure 3 As shown, in this embodiment, the tab assembly 1 includes two first connecting portions 101 and one second connecting portion 102. One first connecting portion 101 is disposed near the inner wall of the housing 3, and the other first connecting portion 101 is disposed near the core hole 401. The second connecting portion 102 is located between the two first connecting portions 101. That is, the outer and inner edges of the tab assembly 1 are relatively thin, while the middle portion of the tab assembly 1 is relatively thick.

[0057] like Figure 3 As shown, in this embodiment, the tab assembly 1 has a fan-shaped structure. The part near the inner edge of the tab assembly 1 is one of the first connecting parts 101, the part near the outer edge of the tab assembly 1 is another first connecting part 101, and the middle part between the two first connecting parts 101 is a second connecting part 102.

[0058] Accordingly, the current collector 2 includes two first connection areas 201 and a second connection area 202, with the second connection area 202 located between the two first connection areas 201.

[0059] To facilitate welding operations between the tab assembly 1 and the current collector 2 and reduce the difficulty of the welding operation, the first connecting area 201 is positioned corresponding to the first connecting part 101, and similarly, the second connecting area 202 is positioned corresponding to the second connecting part 102. Specifically, the current collector 2 includes two first connecting areas 201 and one second connecting area 202. One first connecting area 201 is located near the inner wall of the housing 3, and the other first connecting area 201 is located near the core hole 401. The second connecting area 202 is located between the two first connecting areas 201, making the first connecting area 201 closer to the first connecting part 101, which facilitates the welding operation between the two. Similarly, the second connecting area 202 is closer to the second connecting part 102, which also facilitates the welding operation between the two.

[0060] like Figures 4-6 As shown, to facilitate the manufacturing and forming of the first connection area 201 and the second connection area 202, and to accommodate the fan-shaped tab assembly 1, in this embodiment, a shallow groove 203 is formed on the side of the current collector 2 facing away from the tab assembly 1, i.e., on the upper surface 204 of the current collector. The groove 203 is recessed inward and is fan-shaped. It should be noted that the groove 203 does not penetrate the current collector 2.

[0061] There are two grooves 203, which are symmetrically arranged with respect to the battery axis. The two grooves 203 correspond to the positive electrode tab assembly and the negative electrode tab assembly, respectively. Figure 4 Taking a perspective example, the area between the inner edge of the groove 203 and the center of the collector 2 is the first connection area 201, the bottom of the groove 203 is the second connection area 202, and the area between the outer edge of the groove 203 and the outer peripheral edge of the collector 2 is another first connection area 201.

[0062] In this embodiment, the electrode assembly 1 includes two first connecting portions 101 and one second connecting portion 102. One first connecting portion 101 is disposed near the inner wall of the housing 3, and the other first connecting portion 101 is disposed near the core hole 401 of the core 4. The positions of the two first connecting areas 201 correspond to the positions of the two first connecting portions 101, and the thickness of the two first connecting portions 101 ranges from 0.1mm to 0.4mm. Since the thickness of the two first connecting portions 101 is relatively thin, for example, the thickness of the first connecting portions 101 can be 0.1mm, 0.15mm, 0.2mm, 0.22mm, 0.3mm, 0.36mm, or 0.4mm. Correspondingly, the thickness of the first connecting area 201 of the current collector 2 should be increased to prevent the core 4 from being melted and penetrated during welding operations, ensuring the safety of the welding operation and reducing the difficulty of the welding operation.

[0063] Of course, the thickness of the two first connecting parts 101 in the tab assembly 1 can be the same or different, and this embodiment does not limit this.

[0064] Furthermore, along the height direction of the battery, the first connection area 201 and the first connection portion 101 at least partially overlap.

[0065] To facilitate welding operations between the first connecting portion 101 and the first connecting area 201, the first connecting area 201 and the first connecting portion 101 at least partially overlap along the height direction of the battery. In other words, from a top view, the first connecting area 201 and the first connecting portion 101 at least partially overlap, so that the first connecting portion 101 and the first connecting area 201 are relatively close in the horizontal direction, thereby facilitating welding operations between the first connecting portion 101 and the first connecting area 201 and reducing the difficulty of welding operations.

[0066] Along the height direction of the battery, the overlapping area of ​​the first connection area 201 and the first connection part 101 can be selected as needed. For example, the first connection area 201 and the first connection part 101 can completely overlap or partially overlap.

[0067] Furthermore, the battery also includes a housing 3, a current collector 2 and a tab assembly 1 disposed inside the housing 3, and a first connecting portion 101 disposed near the inner wall of the housing 3. In the direction perpendicular to the height of the battery, the outer edge of the first connecting portion 101 near the inner wall of the housing 3 is inside the outer edge of the first connecting area 201 near the inner wall of the housing 3.

[0068] One of the first connecting portions 101 of the tab assembly 1 is located near the inner wall of the housing 3, and the first connecting area 201 electrically connected to the first connecting portion 101 is also located near the inner wall of the housing 3. The outer edge of the first connecting portion 101 near the inner wall of the housing 3 is located inside the outer edge of the first connecting area 201 near the inner wall of the housing 3. In the direction perpendicular to the battery height, the outer edge of the first connecting portion 101 and the outer edge of the first connecting area 201 are a certain distance apart in the direction perpendicular to the battery height (radial direction of the battery). That is to say, the outer diameter of the current collector 2 is larger than the outer diameter of the tab assembly 1 to ensure that the entire tab assembly 1 can be welded to the current collector 2, thereby ensuring the current carrying capacity between the tab assembly 1 and the current collector 2.

[0069] Furthermore, the distance between the outer edge of the first connecting portion 101 near the inner wall of the housing 3 and the outer edge of the first connecting area 201 near the inner wall of the housing 3 is d, 0. <d≤4mm。

[0070] The distance d between the outer edge of the first connecting portion 101 close to the inner wall of the housing 3 and the outer edge of the first connecting region 201 close to the inner wall of the housing 3 should not be too large. If the distance d is too large, the first connecting region 201 and the first connecting portion 101 are far apart in the direction perpendicular to the height of the battery (radially of the battery), which is not conducive to the welding operation of the outer portions of the first connecting region 201 and the first connecting portion 101.

[0071] In this embodiment, 0 < d ≤ 4 mm for this distance. For example, the distance d can be 0.5 mm, 1 mm, 2 mm, 3 mm, 3.5 mm, 4 mm, etc. Within this distance range, the first connecting region 201 and the first connecting portion 101 are not too far apart in the direction perpendicular to the height of the battery (radially of the battery), facilitating the welding of the first connecting region 201 and the first connecting portion 101, reducing the welding difficulty, and ensuring the welding quality.

[0072] Furthermore, the thickness ratio range of the first connecting portion 101 and the second connecting portion 102 is 0.2 - 0.8. Correspondingly, the thickness ratio range of the first connecting region 201 and the second connecting region 202 is 0.2 - 0.8.

[0073] In this embodiment, the thicknesses of the first connecting portion 101 and the second connecting portion 102 of the tab assembly 1 are different, and the thickness of the first connecting portion 101 is less than that of the second connecting portion 102, but the thickness difference between the two should not be too large. If the thickness difference between the first connecting portion 101 and the second connecting portion 102 is too large, it will exacerbate the problem of poor consistency in the welding effect between the tab assembly 1 and the current collector 2, which is not conducive to adjusting the consistency of the welding effect between the tab assembly 1 and the current collector 2.

[0074] In this embodiment, the thickness ratio range of the first connecting portion 101 and the second connecting portion 102 is 0.2 - 0.8. Under the above ratio range, the thickness difference between the first connecting portion 101 and the second connecting portion 102 will not be too large. By setting the current collector 2 with inconsistent thicknesses, the consistency of the welding effect between the tab assembly 1 and the current collector 2 can be effectively improved, the welding strength between the tab assembly 1 and the current collector 2 can be increased, and the current-carrying capacity between the tab assembly 1 and the current collector 2 can be ensured.

[0075] For example, the thickness ratio of the first connecting portion 101 and the second connecting portion 102 can be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, etc.

[0076] Accordingly, in this embodiment, the thicknesses of the first connecting region 201 and the second connecting region 202 of the current collector 2 are different, with the first connecting region 201 being thicker than the second connecting region 202. However, the difference in thickness should not be too large, and should be adapted to the difference in thickness between the first connecting portion 101 and the second connecting portion 102. If the difference in thickness between the first connecting region 201 and the second connecting region 202 is too large, the consistency of the welding effect between the tab assembly 1 and the current collector 2 cannot be effectively improved.

[0077] For example, the thickness ratio of the first connection area 201 to the second connection area 202 can be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, etc.

[0078] Furthermore, the thickness of the first connection region 201 ranges from 0.2mm to 0.6mm, and the thickness of the second connection region 202 ranges from 0.1mm to 0.4mm.

[0079] To accommodate the thickness difference between the first connecting portion 101 and the second connecting portion 102, the thickness of the first connecting region 201 is greater than the thickness of the second connecting region 202. In this embodiment, the thickness range of the first connecting region 201 is 0.2mm-0.6mm, and the thickness range of the second connecting region 202 is 0.1mm-0.4mm.

[0080] The thickness of the first connecting area 201 should not be too small or too large. If the thickness of the first connecting area 201 is too small, it will not be able to effectively prevent the core 4 from being damaged by melting when the first connecting part 101 and the first connecting area 201 are welded, and there will still be problems of poor welding safety and high welding difficulty. If the thickness of the first connecting area 201 is too large, it will easily cause problems of false welding and poor welding quality between the first connecting part 101 and the first connecting area 201, affecting the current carrying capacity between the two.

[0081] In this embodiment, the thickness of the first connecting area 201 ranges from 0.2mm to 0.6mm. Within this range, the thickness of the first connecting area 201 is neither too small nor too large. When the first connecting part 101 and the first connecting area 201 are welded, it can effectively prevent the core 4 from being damaged by melting, ensuring welding safety and reducing welding difficulty. Moreover, it can ensure good welding quality between the first connecting part 101 and the first connecting area 201, ensuring the current carrying capacity between the first connecting part 101 and the first connecting area 201.

[0082] Similarly, the thickness of the second connecting area 202 should not be too small or too large. If the thickness of the second connecting area 202 is too small, the core 4 may be easily melted and damaged when the second connecting part 102 and the second connecting area 202 are welded, which poses a welding safety hazard and increases the welding difficulty. If the thickness of the second connecting area 202 is too large, it will cause the second connecting part 102 and the second connecting area 202 to have a false weld and poor welding quality, which will affect the current flow capacity between the two.

[0083] In this embodiment, the thickness of the second connecting region 202 ranges from 0.1mm to 0.4mm. Within this range, the thickness of the second connecting region 202 is neither too small nor too large. When the second connecting part 102 and the second connecting region 202 are welded, it can effectively prevent the core 4 from being damaged by melting, ensuring welding safety and reducing welding difficulty. Moreover, it can ensure good welding quality between the second connecting part 102 and the second connecting region 202, ensuring the flow capacity between the second connecting part 102 and the second connecting region 202.

[0084] Furthermore, the battery is a cylindrical battery, and in the radial direction of the battery, the width of the first connection area 201 ranges from 2mm to 8mm, and the width of the second connection area 202 ranges from 4mm to 12mm.

[0085] In the radial direction of the battery, the width of the first connection area 201 should not be too small or too large. If the width of the first connection area 201 is too small, the thicker areas on the current collector 2 will be smaller, and the thinner areas on the current collector 2 will be larger. When welding the tab assembly 1 and the current collector 2, it is easy for the core 4 to melt and be damaged, resulting in low welding safety and high welding difficulty. On the other hand, if the width of the first connection area 201 is too large, the thicker areas on the current collector 2 will be larger, and the thinner areas on the current collector 2 will be smaller. When welding the tab assembly 1 and the current collector 2, it is easy for problems such as incomplete welding and poor welding to occur, affecting the welding quality of the tab assembly 1 and the current collector 2, and thus affecting the current carrying capacity of the tab assembly 1 and the current collector 2, which will have an adverse effect on the overall performance of the battery.

[0086] Similarly, the width of the second connection area 202 should not be too small or too large. If the width of the second connection area 202 is too small, the thinner areas on the current collector 2 will be smaller and the thicker areas on the current collector 2 will be larger. When welding the tab assembly 1 and the current collector 2, problems such as incomplete welding or poor welding are likely to occur, affecting the welding quality of the tab assembly 1 and the current collector 2, and consequently affecting the current carrying capacity of the tab assembly 1 and the current collector 2, thus adversely affecting the overall performance of the battery. On the other hand, if the width of the second connection area 202 is too large, the thinner areas on the current collector 2 will be larger and the thicker areas on the current collector 2 will be smaller. When welding the tab assembly 1 and the current collector 2, it is easy for the core 4 to melt and be damaged, resulting in low welding safety and greater welding operation difficulty.

[0087] In this embodiment, the width of the first connection area 201 ranges from 2mm to 8mm. Within this range, the width of the first connection area 201 is neither too small nor too large. When welding the tab assembly 1 and the current collector 2, it is less likely to cause melting and damage to the core 4, resulting in high welding safety and low welding operation difficulty. Moreover, it is less likely to cause problems such as incomplete welding or poor welding between the tab assembly 1 and the current collector 2. The welding quality between the tab assembly 1 and the current collector 2 is high, and the current carrying capacity of the tab assembly 1 and the current collector 2 is good, which is beneficial to improving the overall performance of the battery.

[0088] For example, the width of the first connection area 201 can be 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, or 8mm.

[0089] Similarly, in this embodiment, the width of the second connection area 202 ranges from 4mm to 12mm. Within this range, the width of the second connection area 202 is neither too small nor too large. When welding the tab assembly 1 and the current collector 2, it is less likely to cause melting and damage to the core 4, resulting in high welding safety and low welding operation difficulty. Moreover, it is less likely to cause problems such as incomplete welding or poor welding between the tab assembly 1 and the current collector 2. The welding quality between the tab assembly 1 and the current collector 2 is high, and the current carrying capacity of the tab assembly 1 and the current collector 2 is good, which is beneficial to improving the overall performance of the battery.

[0090] For example, the width of the second connection area 202 can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, or 12mm.

[0091] In other embodiments, the battery may also be in other shapes, such as a square battery.

[0092] Although 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 appended claims.

Claims

1. A battery, characterized in that, include: The electrode assembly (1) includes a first connecting part (101) and a second connecting part (102), wherein the thickness of the first connecting part (101) is less than the thickness of the second connecting part (102); The current collector (2) includes a first connection area (201) and a second connection area (202) connected to each other. The thickness of the first connection area (201) is greater than the thickness of the second connection area (202). The first connection part (101) is electrically connected to the first connection area (201), and the second connection part (102) is electrically connected to the second connection area (202).

2. The battery according to claim 1, characterized in that, On the side of the current collector (2) facing away from the tab assembly (1), along the height direction of the battery, the first connection area (201) is higher than the second connection area (202).

3. The battery according to claim 2, characterized in that, The side of the current collector (2) facing the electrode assembly (1) is a plane.

4. The battery according to claim 1, characterized in that, It also includes a housing (3), the current collector (2) and the electrode assembly (1) are disposed inside the housing (3), the first connecting part (101) is disposed near the inner wall of the housing (3), and the thickness of the first connecting area (201) is in the range of 0.2mm-0.8mm.

5. The battery according to claim 1, characterized in that, It also includes a core (4), the tab assembly (1) extends from the end of the core (4), the first connecting part (101) is disposed near the core hole (401) of the core (4), and the thickness of the first connecting area (201) is in the range of 0.2mm-0.8mm.

6. The battery according to claim 5, characterized in that, The end of the first connecting portion (101) is bent away from the core hole (401), and the thickness of the first connecting area (201) is in the range of 0.2mm-0.5mm.

7. The battery according to claim 1, characterized in that, The electrode assembly (1) includes two first connecting parts (101) and one second connecting part (102), with the second connecting part (102) located between the two first connecting parts (101).

8. The battery according to claim 7, characterized in that, The current collector (2) includes two first connection areas (201) and one second connection area (202), with the second connection area (202) located between the two first connection areas (201).

9. The battery according to claim 8, characterized in that, It also includes a housing (3) and a core (4), wherein the current collector (2) and the electrode assembly (1) are disposed in the housing (3), and the electrode assembly (1) extends out from the end of the core (4); One of the first connecting parts (101) is disposed near the inner wall of the housing (3), and the other first connecting part (101) is disposed near the core hole (401) of the core (4). The thickness of the two first connecting parts (101) is in the range of 0.1mm-0.4mm.

10. The battery according to claim 1, characterized in that, Along the height direction of the battery, the first connection area (201) and the first connection portion (101) at least partially overlap.

11. The battery according to claim 1, characterized in that, It also includes a housing (3), the current collector (2) and the tab assembly (1) are disposed inside the housing (3), the first connecting part (101) is disposed near the inner wall of the housing (3), and in the direction perpendicular to the height of the battery, the first connecting part (101) is located near the outer edge of the inner wall of the housing (3) on the inner side of the first connecting area (201) near the outer edge of the inner wall of the housing (3).

12. The battery according to claim 11, characterized in that, The distance between the outer edge of the first connecting portion (101) near the inner wall of the housing (3) and the outer edge of the first connecting area (201) near the inner wall of the housing (3) is d, 0. <d≤4mm。 13. The battery according to claim 1, characterized in that, The thickness ratio of the first connecting portion (101) to the second connecting portion (102) is in the range of 0.2-0.

8. Correspondingly, the thickness ratio of the first connecting area (201) to the second connecting area (202) is in the range of 0.2-0.

8.

14. The battery according to claim 1, characterized in that, The thickness of the first connection area (201) ranges from 0.2mm to 0.6mm, and the thickness of the second connection area (202) ranges from 0.1mm to 0.4mm.

15. The battery according to any one of claims 1-14, characterized in that, The battery is a cylindrical battery. In the radial direction of the battery, the width of the first connection area (201) ranges from 2mm to 8mm, and the width of the second connection area (202) ranges from 4mm to 12mm.

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