Collecting plate and battery

Abstract

The utility model relates to the technical field of batteries, and discloses a collector plate and a battery. The battery comprises a shell, a battery cell and a current collecting disc, the current collecting disc comprises a disc body, the disc body is provided with at least two hollow-out areas arranged at intervals, so that a first welding area, a second welding area and at least two connecting spoke areas are formed on the disc body, the second welding area is arranged on the periphery of the first welding area in a surrounding mode, and the connecting spoke areas are arranged on the periphery of the second welding area. The connecting spoke area extends in the radial direction and is directly connected with the first welding area and the second welding area. According to the current collecting disc, two parts connected with the current collecting disc can be flexibly connected, a part of impact energy is absorbed after the current collecting disc is impacted, and the reliability of connection between the current collecting disc and the two parts is guaranteed. The battery is provided with the current collecting plate, so that the reliability of connection between the current collecting plate and the battery cell and the shell can be kept under the high-shock-resistance working condition, and the safety is high.

Description

Technical Field

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

[0002] The drum test is an important test method for battery safety. During the test, the battery is placed inside the drum, and the drum rotates, causing mechanical collision between the battery and the drum. The retention rate of the battery's internal pressure and internal resistance after the drum test is an important indicator for battery development.

[0003] Currently, some cylindrical battery cells use a full-tab configuration, with the tabs connected to the battery's steel casing via a collector plate. As collector plates become thinner and lighter, excessive welding energy between the collector plate and the tabs can easily melt through the weld interface and erode the cell's diaphragm. However, insufficient welding energy can lead to insufficient tension between the collector plate and the tabs / steel casing, resulting in failure to pass the roller test. This means the battery won't meet the requirements for use in high-seismic conditions.

[0004] Therefore, a current collecting plate and a battery are urgently needed to solve the above technical problems. Utility Model Content

[0005] One purpose of the utility model is to provide a collecting plate, which can form a flexible connection between two components connected thereto and absorb a portion of the impact energy after being impacted, thereby ensuring the reliability of the connection between the collecting plate and the two components.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] The collecting plate includes a plate body, and at least two hollow areas arranged at intervals are opened on the plate body to form a first welding area, a second welding area and at least two connecting spokes on the plate body, the second welding area is arranged around the outer periphery of the first welding area, and the connecting spokes extend radially and directly connect the first welding area and the second welding area.

[0008] As an optional solution, at least three hollow areas are arranged at intervals on the disc body.

[0009] As an optional solution, at least two of the connecting spokes are evenly distributed along the circumference of the disk body.

[0010] As an optional solution, the hollow area includes:

[0011] An arc portion, wherein the first welding area is located between the arc portions of at least two of the hollow areas;

[0012] Two extension parts are respectively connected to the two ends of the arc part and extend toward the edge of the disk body. The connecting spoke area is between the two adjacent extension parts of the two adjacent hollow areas. The maximum distance between the hollow area and the center of the disk body is C, 4mm≤C<8mm.

[0013] As an optional solution, along the radial direction of the disk body, the connecting spoke area includes a main body portion and a narrowing portion, and the maximum width of the narrowing portion is smaller than the width of the main body portion.

[0014] As an optional solution, the narrowing portion is provided at one end of the connecting spoke area close to the center of the current collecting disk, and the main body portion is provided at one end of the connecting spoke area close to the edge of the current collecting disk.

[0015] As an optional solution, the width of the main body is B1, 1mm≤B1≤4mm.

[0016] As an optional solution, the width of the main body is B1, the minimum width of the narrowed portion is B2, and 0.5B1≤B2<B1.

[0017] As an optional solution, the first welding area is circular, and the diameter of the first welding area is D, 3mm≤D≤5mm.

[0018] Another object of the present invention is to provide a battery that, by adopting the above-mentioned current collecting plate, can maintain the reliability of the connection between the current collecting plate and the battery cell and the casing respectively under high seismic conditions, thereby achieving high safety.

[0019] To achieve this purpose, the present invention adopts the following technical solutions:

[0020] The battery comprises a shell, a battery cell and the current collecting plate, wherein the battery cell is arranged in the shell, the current collecting plate is arranged between the shell and the battery cell, the shell is welded to the first welding area, and the battery cell is welded to the second welding area.

[0021] The beneficial effects of the utility model are:

[0022] The collecting plate of the utility model:

[0023] (1) By opening at least two hollow areas on the disc body, a first welding area, a second welding area and at least two connecting spokes are formed on the disc body. After the first welding area and the second welding area are welded to the battery shell and the battery cell respectively, the connecting spokes connecting the first welding area and the second welding area can be deformed to a certain extent, so that the connection between the shell and the battery cell forms a flexible connection. When the battery is subjected to external impact force, the connecting spokes can absorb part of the impact energy through their own deformation, thereby greatly reducing the pulling force between the current collecting disc and the battery cell, and between the current collecting disc and the shell during the impact process, thereby ensuring the reliability of the current collecting disc connection; in addition, since the connecting spokes are directly connected to the first welding area and the second welding area, the resistance when the current flows through the current collecting disc can be minimized.

[0024] (2) A narrowing portion is provided on the connecting spoke area, thereby weakening the stiffness of the connecting spoke area, that is, increasing the deformation capacity of the connecting spoke area. On the premise of meeting the current conduction capacity, the impact energy can be absorbed more effectively after the battery is impacted, thereby improving the connection reliability between the collecting plate and the battery cell and the shell respectively.

[0025] The battery of the present invention, by adopting the above-mentioned current collecting plate, can not only maintain the reliability of the connection between the current collecting plate and the battery cell and the casing respectively under high seismic resistance conditions, thereby ensuring the safety of the battery, but also the resistance of the current flowing through the current collecting plate is small, which is conducive to maintaining a low internal resistance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a cross-sectional view of a battery provided by a specific embodiment of the present utility model;

[0027] Figure 2 This is a three-dimensional diagram of the first current collecting plate provided by the specific embodiment of the utility model;

[0028] Figure 3 It is a top view of the second current collecting plate provided in a specific embodiment of the present utility model;

[0029] Figure 4 This is a top view of the first current collecting plate provided in a specific embodiment of the present utility model;

[0030] Figure 5 This is a top view of a third type of current collecting plate provided in a specific embodiment of the present utility model;

[0031] Figure 6 It is a structural diagram of a battery cell and a current collecting plate provided in a specific embodiment of the utility model;

[0032] Figure 7 This is a schematic diagram of the welding track on the first collector provided by the specific embodiment of the utility model. Figure 1 ;

[0033] Figure 8 This is a schematic diagram of the welding track on the first collector provided by the specific embodiment of the utility model. Figure 2 .

[0034] In the picture:

[0035] 10. Collecting plate; 101. Hollow area; 1011. Arc portion; 1012. Extension portion; 11. First welding area; 12. Second welding area; 13. Connecting spoke area; 131. Main body; 132. Narrowing portion;

[0036] 20. Battery cell; 21. Center hole;

[0037] 30. Shell;

[0038] 40. Connectors;

[0039] 50. Blocked shots;

[0040] 61. Welding line; 62. Welding point. DETAILED DESCRIPTION

[0041] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0042] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0043] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0044] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0045] This embodiment provides a current collecting plate and a battery, such as Figure 1 As shown, the battery includes a housing 30, a battery cell 20, a current collecting plate 10, a connector 40, and a cap 50. The housing 30 forms a receiving cavity, the battery cell 20 is arranged in the receiving cavity, the current collecting plate 10 is arranged between one end of the battery cell 20 and the housing 30, and is used to electrically connect the battery cell 20 and the housing 30. The cap 50 is installed at the end of the housing 30 away from the current collecting plate 10, and the connector 40 is arranged between the other end of the battery cell 20 and the cap 50, and is used to achieve electrical connection between the battery cell 20 and the cap 50. Optionally, the battery in this embodiment is a cylindrical battery, and the battery cell 20 is a wound battery cell. Optionally, the wound battery cell 20 is a full-tab design.

[0046] As the design of the collecting plate 10 tends to be lighter and thinner, if the welding energy between the collecting plate 10 and the tab is too large, it is easy to melt through the welding interface and burn the diaphragm of the battery cell 20. If the welding energy is too small, it will lead to insufficient tension between the collecting plate 10 and the tab / housing, and thus fail to pass the roller test. In other words, the battery cannot meet the usage requirements under high seismic resistance conditions.

[0047] In this regard, Figure 2 As shown, the collector plate 10 of this embodiment includes a circular plate body with at least two hollow areas 101 formed therein, thereby forming a first welding area 11, a second welding area 12, and at least two connecting spokes 13. The second welding area 12 is disposed around the periphery of the first welding area 11, and the connecting spokes 13 directly connect the first welding area 11 and the second welding area 12 in a radial direction. It should be noted that in this embodiment, "radial" refers to the direction extending from the center of the collector plate 10 to the edge of the collector plate 10, and is not a strict diameter direction.

[0048] In this embodiment, the first welding region 11 is welded to the outer shell 30, and the second welding region 12 is welded to the tab of the battery cell 20. After welding, the connecting spoke 13 connecting the first welding region 11 and the second welding region 12 can deform to a certain extent, thereby forming a flexible connection between the outer shell 30 and the battery cell 20. When the battery is subjected to external impact, the connecting spoke 13 can absorb some of the impact energy through its own deformation, thereby significantly reducing the pulling force between the current collecting plate 10 and the battery cell 20, and between the current collecting plate 10 and the outer shell 30 during the impact, ensuring the reliability of the connection of the current collecting plate 10. In addition, because the connecting spoke 13 directly connects the first welding region 11 and the second welding region 12, the resistance to current flowing through the current collecting plate 10 can be minimized. By using this current collecting plate 10, the battery can not only maintain the reliability of the connection between the current collecting plate 10 and the battery cell 20 and the outer shell 30 under high-seismic conditions, thus ensuring battery safety, but also reduce the resistance to current flowing through the current collecting plate 10, which helps maintain a low internal resistance of the battery.

[0049] In this embodiment, the collecting disc 10 is integrally formed, ensuring that the connecting spokes 13 have sufficient elastic deformation capability. Alternatively, the collecting disc 10 can be formed from copper strip, nickel strip, or a copper-nickel composite strip by stamping, flattening, and cleaning. The specific material of the collecting disc 10 can be selected based on actual needs and is not specifically limited here.

[0050] In some embodiments, such as Figure 3 As shown, the collecting plate 10 has two hollow areas 101 on its body. The two hollow areas 101 are arranged opposite to each other, and connecting spokes 13 are formed at opposite ends of the two hollow areas 101. That is, the collecting plate 10 includes two connecting spokes 13. In some embodiments, such as Figure 4 As shown, the collecting plate 10 has three hollow areas 101 formed on the plate body. The three hollow areas 101 are arranged at intervals along the circumference of the collecting plate 10. A connecting spoke 13 is formed between the opposite ends of each two adjacent hollow areas 101. That is, the collecting plate 10 includes three connecting spokes 13. In some embodiments, such as Figure 5 As shown, the collecting disc 10 is provided with four hollow areas 101 on its disc body. The four hollow areas 101 are arranged at intervals along the circumference of the collecting disc 10. The opposite ends of each two adjacent hollow areas 101 form a connecting spoke 13, that is, the collecting disc 10 includes four connecting spokes 13. It is understandable that in other embodiments, the specific number of hollow areas 101 can be flexibly set as needed and is not specifically limited here. According to the data obtained from the experiment, it can be seen that two connecting spokes 13 are the minimum of the present invention, but its technical effect cannot achieve the best technical effect. One reason is that the number of connecting spokes 13 is too small, which limits the current conduction capability. The other reason is that the two connecting spokes 13 arranged opposite each other weaken its ability to absorb impact and deformation. It can achieve the technical effect of the present invention.

[0051] However, a more optimal solution is to use 3-6 connecting spokes 13. Three connecting spokes 13 are the optimal solution for this invention, providing excellent current conduction capabilities. Furthermore, the three connecting spokes 13 are staggered at 120 degrees, which provides the best impact and deformation absorption capabilities. Similarly, four connecting spokes 13 are also a preferred solution for this invention, and 5-6 connecting spokes 13 are also possible solutions for this invention (not shown).

[0052] like Figure 3-Figure 5 As shown, at least two connecting spokes 13 are evenly distributed along the circumference of the disc. This arrangement ensures that the areas of the current collecting disc 10 that can absorb impact energy are evenly distributed along the circumference. This ensures that when the battery is impacted from different directions, the current collecting disc 10 can reliably absorb the impact energy, ensuring the safety of the battery under severe seismic conditions.

[0053] Take the case where the collecting plate 10 has three hollow areas 101 as an example. Figure 4 As shown, the hollow area 101 includes an arc portion 1011 and two extensions 1012. A first welding area 11 is formed between the arc portions 1011 of each hollow area 101. The two extensions 1012 are connected to the ends of the arc portions 1011 and extend toward the edge of the disk body. A connecting spoke 13 is formed between two adjacent extensions 1012 of two adjacent hollow areas 101. The entire disk body, excluding the first welding area 11 and the connecting spoke 13, comprises a second welding area 12. This arrangement maximizes the area available for welding on the current collecting disk 10 while ensuring that the connecting spoke 13 can absorb impact energy through its own deformation. Optionally, in this embodiment, the extensions 1012 extend generally radially of the current collecting disk 10, so the connecting spoke 13 between the two extensions 1012 also extends generally radially of the current collecting disk 10.

[0054] In this embodiment, Figure 4 As shown, the first welding area 11 is circular, with a diameter D of 3mm≤D≤5mm. Setting the diameter of the first welding area 11 within this range ensures that the first welding area 11 has sufficient area for welding to the battery casing 30, ensuring reliable welding between the current collecting tray 10 and the casing 30. It also prevents the first welding area 11 from being too large while the second welding area 12 is insufficient, ensuring reliable welding between the current collecting tray 10 and the battery cell 20. Alternatively, the diameter of the first welding area 11 can be 3mm, 3.5mm, 4mm, 4.5mm, 5mm, etc.

[0055] In this embodiment, the maximum distance between the hollow area 101 and the center of the disc body is C, where 4mm≤C<8mm. This arrangement ensures that the connecting web 13 connecting the first welding area 11 and the second welding area 12 is of sufficient length, thereby providing sufficient impact energy absorption, while also preventing the hollow area 101 from being too long and affecting the overall structural strength of the current collecting disc 10.

[0056] like Figure 4 As shown, along the direction from the first welding area 11 to the second welding area 12 (i.e., the radial direction of the current collecting plate 10), the connecting spoke 13 includes a main portion 131 and a narrowed portion 132. The maximum width of the narrowed portion 132 is smaller than the width of the main portion 131. The provision of the narrowed portion 132 weakens the rigidity of the connecting spoke 13, thereby increasing its deformation capacity. While maintaining current conduction capacity, it can more effectively absorb impact energy after the battery is impacted, thereby improving the reliability of the connection between the current collecting plate 10 and the battery cell 20 and the housing 30.

[0057] like Figure 4 As shown, the narrowing portion 132 is disposed at one end of the connecting spoke 13 near the center of the collecting disk 10, and the main portion 131 is disposed at one end of the connecting spoke 13 near the edge of the collecting disk 10. The smaller the area of ​​the circular ring near the center of the collecting disk 10, the smaller the area available for welding. In this embodiment, the narrowing portion 132 with a smaller width is disposed at one end near the center of the collecting disk 10, and the main portion 131 with a larger width is disposed at one end near the edge of the collecting disk 10, so that the radial area occupied by the connecting spoke 13 matches the radial area distribution of the entire collecting disk 10, ensuring that the first welding area 11 also retains sufficient welding area in the radially near-center portion. In this embodiment, the width of the narrowing portion 132 gradually increases in the radial direction from the inside to the outside, thereby achieving a smooth transition between the narrowing portion 132 and the main portion 131, thereby avoiding local stress concentration in the connecting spoke 13.

[0058] Optionally, the width of the main body 131 is B1, where 1mm≤B1≤4mm. By setting the width of the main body 131 within the aforementioned range, the connecting spokes 13 are ensured to have sufficient impact energy absorption capacity while also preventing damage to the connecting spokes 13 during impact due to insufficient rigidity. Optionally, the width of the main body 131 can be 1mm, 2mm, 3mm, 4mm, etc. It is understood that in actual applications, the width of the main body 131 can be adjusted based on the number of connecting spokes 13 on the collecting plate 10 and is not specifically limited here.

[0059] The second welding area 12 has a shape with two sharp corners in a region close to the first welding area 11 , which matches the narrowed portion 132 and the main body portion 131 . This shape enables the first welding area 11 to have a larger welding area.

[0060] Optionally, the width of the main portion 131 is B1, and the minimum width of the narrowed portion 132 is B2, where 0.5B1 ≤ B2 < B1. This arrangement not only reduces the rigidity of the connecting spoke 13 but also prevents damage to the connecting spoke 13 due to excessive rigidity. Optionally, the value of B2 can be 0.5B1, 0.6B1, 0.7B1, 0.8B1, 0.9B1, etc., without specific limitation.

[0061] As for the diameter of the entire collecting plate, the battery cell in the present invention is preferably a cylindrical battery cell of the 18650 series and the 21700 series, the diameters of which are 18 mm and 21 mm respectively. Figure 6 and Figure 7 It can be seen that the collecting plate is only slightly smaller than the battery cell, and the diameter of the battery cell is basically the same as the diameter of the outer shell of the battery cell. Therefore, according to different battery models, the diameter of the collecting plate can be selected to be slightly smaller than 18mm or 21mm.

[0062] like Figure 6 As shown, taking the battery as a full-ear cylindrical battery as an example, the battery assembly process is roughly as follows:

[0063] Winding-molded full-tab battery cell 20;

[0064] Welding the tab at one end of the battery cell 20 to the second welding area 12 of the current collecting plate 10;

[0065] Install the welded battery cell 20 and the current collecting plate 10 into the housing 30 so that the current collecting plate 10 contacts the bottom of the housing 30;

[0066] The welding tool penetrates the central hole 21 of the battery cell 20 from the end away from the current collecting plate 10 and extends into the first welding area 11 of the current collecting plate 10. The welding tool welds the first welding area 11 and the housing 30;

[0067] The connector 40 and the cap 50 are assembled and the housing 30 is sealed.

[0068] Taking the three hollow areas 101 provided on the collecting plate 10 as an example, in some embodiments, Figure 7 As shown, the welding trajectory between the battery cell 20 and the current collecting tray 10 includes multiple welding lines 61, wherein some welding lines 61 are located between two extensions 1012 of the same hollow area 101, and some welding lines 61 are located between the ends of two hollow areas 101 and the edge of the current collecting tray 10. Optionally, the trajectory of each welding line 61 can be set to an arc, a straight line, a wavy shape, or a broken line, which is not specifically limited here.

[0069] In some embodiments, such as Figure 8As shown, the welding path between the battery cell 20 and the current collecting tray 10 is a plurality of welding points 62, some of which are located between two extensions 1012 of the same hollow area 101, and some of which are located between the ends of the two hollow areas 101 and the edge of the current collecting tray 10. The specific number and density of the welding points 62 can be flexibly set and are not specifically limited here.

[0070] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. Those skilled in the art will, based on the concept of the present invention, vary the specific implementation methods and scope of application, and the contents of this specification should not be construed as limiting the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A collecting plate, characterized in that: The invention comprises a disk body, wherein at least two hollow areas (101) are provided at intervals, so that a first welding area (11), a second welding area (12) and at least two connecting spoke areas (13) are formed on the disk body, wherein the second welding area (12) is arranged around the outer periphery of the first welding area (11), and the connecting spoke area (13) extends radially and directly connects the first welding area (11) and the second welding area (12).

2. The collecting tray according to claim 1, wherein: The disk body is provided with at least three hollow areas (101) arranged at intervals.

3. The collecting tray according to claim 1, wherein: At least two connecting spokes (13) are evenly distributed along the circumference of the disk body.

4. The collecting tray according to claim 1, wherein: The hollow area (101) includes: An arc portion (1011), wherein the first welding area (11) is located between the arc portions (1011) of at least two of the hollow areas (101); Two extension portions (1012) are respectively connected to the two ends of the arc portion (1011) and extend toward the edge of the disk body. The connecting spoke area (13) is located between two adjacent extension portions (1012) of two adjacent hollow areas (101). The maximum distance between the hollow area (101) and the center of the disk body is C, and 4mm≤C<8mm.

5. The collecting tray according to any one of claims 1 to 4, characterized in that: Along the radial direction of the disk body, the connecting spoke area (13) comprises a main body portion (131) and a narrowing portion (132), and the maximum width of the narrowing portion (132) is smaller than the width of the main body portion (131).

6. The collecting tray according to claim 5, wherein: The narrowing portion (132) is arranged at one end of the connecting spoke area (13) close to the center of the current collecting disk, and the main body (131) is arranged at one end of the connecting spoke area (13) close to the edge of the current collecting disk.

7. The collecting tray according to claim 5, wherein: The width of the main body (131) is B1, 1mm≤B1≤4mm.

8. The collecting tray according to claim 5, wherein: The width of the main body (131) is B1, the minimum width of the narrowed portion (132) is B2, and 0.5B1≤B2<B1.

9. The collecting tray according to any one of claims 1 to 4, characterized in that: The first welding area (11) is circular in shape, and the diameter of the first welding area (11) is D, 3mm≤D≤5mm.

10. A battery, characterized in that The invention comprises a housing (30), a battery cell (20) and a current collecting plate according to any one of claims 1 to 9, wherein the battery cell (20) is arranged in the housing (30), the current collecting plate is arranged between the housing (30) and the battery cell (20), the housing (30) is welded to the first welding area (11), and the battery cell (20) is welded to the second welding area (12).

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