Wire-wound battery cells, cylindrical batteries, and electrical devices
Patent Information
- Application Number
- JP2026515134
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-09-28
- Filing Date
- 2024-07-05
- Publication Date
- 2026-10-14
Smart Images
Figure 2026534025000001_ABST
Abstract
Description
TECHNICAL FIELD
[0001] Cross-Reference to Related Applications The present disclosure claims priority to Chinese Patent Application No. 202322680151.3 filed on September 28, 2023, the entire contents of which are incorporated herein by reference. BACKGROUND ART
[0002] The present disclosure relates to the field of wound battery cells, cylindrical batteries, and electrical devices.
[0003] Electrode sheet winding is one of the common manufacturing methods for cylindrical battery cells. After the electrode sheet is wound, the tabs are flattened and then welded to the current collector plate. In the related art, in order to prevent interference between the tabs and the winding needle during the winding process, no tab is provided in the winding start section of the electrode sheet, which results in a low coverage rate of the tabs on the electrode sheet and a reduced overcurrent capacity of the wound battery cell. SUMMARY OF THE INVENTION
[0004] The present disclosure aims to at least partially solve one of the above-mentioned technical problems in the prior art.
[0005] From this perspective, the present disclosure needs to provide a wound battery cell with greater overcurrent capability.
[0006] The present disclosure also provides a cylindrical battery having the above-described wound battery cell.
[0007] The present disclosure also provides an electrical device including the above cylindrical battery.
[0008] According to the wound battery cell provided in this disclosure, the wound battery cell is formed by windings and has a reel hole defined on the inside, the wound battery cell includes an electrode sheet, the electrode sheet includes an active material coating portion and a tab portion, the tab portion is connected to one side of the active material coating portion in the width direction, the tab portion includes a plurality of tabs arranged in the longitudinal direction of the electrode sheet, one end of the electrode sheet facing the reel hole in the winding direction is a winding start section, and the other end of the electrode sheet opposite to the winding start section in the winding direction is a winding tail end. The tab portion of the winding start section is a first tab portion, the first tab portion includes a plurality of first tabs, the edge of the side of the first tab facing the reel hole in the winding direction is a first side edge, the first side edge extends obliquely toward the end of the winding in the direction from the active material coating portion toward the tab portion, the height dimension of the first tab extending from the active material coating portion is a first height in the direction of the active material coating portion facing the tab portion, and the first height of the plurality of first tabs increases in the winding direction.
[0009] According to the wound battery cell of the embodiment of the present disclosure, the first height of the plurality of first tabs is increased in the winding direction of the wound battery cell, thereby increasing the covering area of the tabs on the electrode sheet, thereby increasing the overcurrent withstand capability of the wound battery cell, and increasing the covering area of the flattened tabs at the ends of the wound battery cell, thereby further improving the overcurrent withstand capability of the wound battery cell. Furthermore, the number of overlapping layers of the first tabs is increased, thereby reducing the possibility of the first tabs burning out and damaging the electrode sheet beneath the first tabs when welding the current collector to the first tabs, thereby improving the yield of cylindrical batteries. By extending the first side edge obliquely, the number of overlapping regions between the first tabs is increased, thereby increasing the number of weldable regions on the first tabs. This facilitates the connection between the current collector and the first tabs, and therefore ultimately improves the manufacturing efficiency of cylindrical batteries.
[0010] In addition, according to the wound battery cell of the embodiment of the present disclosure, the wound battery cell may further have the following additional technical features.
[0011] According to one embodiment of the present disclosure, the first height of the first tab among a plurality of first tabs that is closest to the end of the end facing the reel hole of the winding start section is 1 mm or less.
[0012] According to one embodiment of the present disclosure, the angle between the inclined extension direction of the first side edge and the longitudinal direction of the electrode sheet is a first angle, and the first angle of a plurality of first tabs gradually increases along the winding direction.
[0013] According to one embodiment of the present disclosure, the first angles of the plurality of first tabs increase linearly along the winding direction.
[0014] According to one embodiment of the present disclosure, the first angle of the first tab closest to the end of the end of the winding start section facing the reel hole is in the range of 20° to 30°.
[0015] According to one embodiment of the present disclosure, the lengths of the first side edges of a plurality of first tabs are equal.
[0016] According to one embodiment of the present disclosure, the first tab has a second side edge arranged opposite to the first side edge in the winding direction, the end edge of the first tab away from the active material coating is the first side edge, the first side edge is connected between the first side edge and the second side edge, and the first side edge is connected in an arc shape to both the first side edge and the second side edge.
[0017] According to one embodiment of the present disclosure, the first side edge and the second side edge are arranged in parallel, the first end edge is arranged perpendicular to the first side edge and the second side edge, or the first end edge extends parallel to the length direction of the electrode sheet.
[0018] According to one embodiment of the present disclosure, the first height of a plurality of first tabs increases linearly along the winding direction.
[0019] According to one embodiment of the present disclosure, the plurality of first tabs of the first tab portion are divided into a plurality of tab groups, the plurality of tab groups are arranged sequentially along the winding direction, each tab group contains at least one first tab, the first heights of the plurality of first tabs within each tab group are the same, and in two adjacent tab groups, the first height of the first tab in the tab group located upstream in the winding direction is smaller than the first height of the first tab in the tab group located downstream in the winding direction.
[0020] According to one embodiment of the present disclosure, the distance between two adjacent tabs in the winding direction is 0.05 mm to 2 mm.
[0021] According to one embodiment of the present disclosure, the plurality of tabs are bent toward the side where the reel hole is located, and one end of the plurality of first tabs facing the reel hole is flush with the circumferential wall of the reel hole or is located radially outward from the reel hole.
[0022] According to one embodiment of the present disclosure, the ends of the plurality of first tabs at one end are aligned in the axial direction of the wound battery cell.
[0023] According to one embodiment of the present disclosure, the electrode sheet further includes a body section, the body section being connected to one end away from the reel hole of the winding start section, the tab portion of the body section being a second tab portion comprising a plurality of second tabs, wherein, in the direction of the active material coating portion facing the tab portion, the height dimension of the second tabs extending from the active material coating portion is a second height, and the second heights of the plurality of second tabs are equal.
[0024] According to one embodiment of the present disclosure, the edge of the side of the second tab toward the winding start section in the winding direction is a third side edge, and in the direction toward the tab portion from the active material coating portion, the third side edge extends obliquely toward the winding end.
[0025] According to one embodiment of the present disclosure, the tab portion further includes a connecting region that connects the active material coating portion and the plurality of tabs.
[0026] According to the cylindrical battery provided in the present disclosure, the cylindrical battery includes the wound battery cell of the above-described embodiment.
[0027] According to the electrical device provided in the present disclosure, the electrical device includes the cylindrical battery of the above-described embodiment.
[0028] Further aspects and advantages of the present disclosure are partially set forth in the following description, and will be partially apparent from the description, or may be learned by practice of the present disclosure. [Brief Description of the Drawings]
[0029] [Figure 1] 1 is a schematic diagram of a wound battery cell according to an embodiment of the present disclosure. [Figure 2] 2 is a cross-sectional view of a wound battery cell with tabs in a non-flat state according to an embodiment of the present disclosure. [Figure 3] 3 is a schematic diagram of an electrode sheet according to an embodiment of the present disclosure. [Figure 4] 3 is a schematic diagram of the winding start section shown in FIG. 3. [Figure 5] 5 is a schematic diagram of another electrode sheet according to an embodiment of the present disclosure. [Figure 6] 5 is a schematic diagram of the winding start section shown in FIG. 5. [Figure 7] 6 is a schematic diagram of a cylindrical battery according to an embodiment of the present disclosure. [Mode for Carrying Out the Invention]
[0030] Hereinafter, embodiments of the present disclosure are described in detail, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout the drawings. The embodiments described below with reference to the accompanying drawings are illustrative, are intended to explain the present disclosure, and should not be construed as limiting the present disclosure.
[0031] The following disclosure provides many different embodiments or examples for realizing the various structures of this disclosure. For brevity, specific examples of components and settings are described below. Naturally, these are merely examples and do not limit the scope of this disclosure. In addition, this disclosure may repeat reference numbers and / or reference letters in different examples. This repetition is for brevity and clarity and does not in itself indicate relationships between the various embodiments and / or settings discussed. In addition, this disclosure provides examples of various specific processes and materials, but those skilled in the art will recognize the applicability of using other processes and / or other materials.
[0032] In the following, a wound battery cell 100 according to the first embodiment of this disclosure will be described with reference to Figures 1 to 7.
[0033] As shown in Figures 1 to 3, according to a first embodiment of the present disclosure, a wound battery cell 100 has a reel hole 10 formed by a winding and defined on the inside. The wound battery cell 100 includes an electrode sheet 20, which includes an active material coating portion 21 and a tab portion 22. The tab portion 22 is connected to one side of the active material coating portion 21 in the width direction (such as the up-and-down direction shown in Figure 3), and the tab portion 22 has a plurality of tabs 221 arranged in the length direction of the electrode sheet 20 (such as the left-and-right direction shown in Figure 3). One end of the electrode sheet 20 facing the reel hole 10 in the winding direction (such as the right-to-left direction shown in Figure 3) (such as the left end of the electrode sheet 20 shown in Figure 3) is the winding start section 23, and the other end of the electrode sheet 20 opposite to the start section 23 in the winding direction (such as the right end of the electrode sheet 20 shown in Figure 3) is the winding end. The tab portion 22 of the winding start section 23 is a first tab portion 223, and the first tab portion 223 includes a plurality of first tabs 231. The edge of the side surface of the first tab 231 facing the reel hole 10 in the winding direction is the first side edge 2311. The first side edge 2311 extends diagonally toward the end of the winding in the direction from the active material coating portion 21 toward the tab portion 22. In the direction from the active material coating portion 21 toward the tab portion 22, the height dimension of the first tab 231 extending from the active material coating portion 21 is the first height in the direction of the active material coating portion 21 facing the tab portion 22. That is, in Figure 3, for example, in the direction of the active material coating portion 21 facing the tab portion 22, the distance between the outermost surface of the first tab 231 and the upper side edge of the active material coating portion 21 is formed as the first height. In the vertical direction, the distance b between the uppermost surface of the first tab 231 and the upper edge of the active material coating portion 21 is formed as the first height, and the first height of the multiple first tabs 231 increases in the winding direction.
[0034] The active material coated section 21 is coated with an active material. During the discharge process of the wound battery cell 100, the active material coated section 21 is immersed in an electrolyte. Multiple tabs 221 are connected to a current collector device 200, and the electrolyte reacts with the active material in the active material coated section 21 on the electrode sheet 20 to generate an electric current. The current is transmitted through the electrode sheet 20 to the tabs 221, and the tabs 221 output the current to the outside via the current collector device 200, thereby enabling the discharge process of the wound battery cell 100.
[0035] It should be noted that during the discharge process of the wound battery cell 100, the current flows throughout the electrode sheet 20. Therefore, the overcurrent withstand capability of the wound battery cell 100 can be increased by increasing the covering area of the tabs 221 on the electrode sheet 20. During the winding process of the battery cell 100, as the electrode sheet 20 is wound, the winding diameter of the electrode sheet 20 gradually increases, and the distance between the electrode sheet 20 and the side edge of the reel hole 10 also increases progressively.
[0036] In this embodiment, by increasing the first height of the multiple first tabs 231 in the winding direction of the wound battery cell 100, the first tabs 231 can cover a larger area of the electrode sheet 20 at one end facing the reel hole 10 of the electrode sheet 20. When the wound battery cell 100 discharges, more tabs 221 are used to discharge the current on the electrode sheet 20, thereby increasing the overcurrent withstand capability of the wound battery cell 100.
[0037] In one embodiment of the present disclosure, the first height of the first tab 231 and the angle between the inclined extending direction of the first side edge 2311 and the longitudinal direction of the electrode sheet can be set according to the distance between the first tab 231 and the edge of the reel hole 10, so that the first height of the first tab 231 and the angle between the inclined extending direction of the first side edge 2311 and the longitudinal direction of the electrode sheet 20 are adapted to the distance between the electrode sheet 20 and the edge of the reel hole 10. In this way, after flattening, the first tab 231 can be brought closer to the edge of the reel hole 10, thereby increasing the covering area of the first tab 231 on the circumference of the reel hole 10 and further increasing the covering area of the first tab 231 at the end of the wound battery cell 100. Therefore, when the current collector 200 is connected to the end of the wound battery cell 100, the contact area between the current collector 200 and the first tab 231 is increased, thereby further increasing the overcurrent withstand capability of the wound battery cell 100.
[0038] In addition, after flattening, all of the first tabs 231 are close to the edge of the reel hole 10, so the end of the winding start section 23 having the first tabs 231 can be further flattened after winding, thus facilitating the connection between the wound battery cell 100 and the current collector device 200.
[0039] As shown in Figure 7, in practical applications, the current collector 200 is typically welded to a flattened tab 221. However, in this field, it is understood that the tab 221 is relatively thin and therefore easily susceptible to burning during the welding process. During the winding process of the electrode sheet 20, the tabs overlap with the tabs from the previous winding, forming an overlapping area. Welding the current collector 200 to the overlapping area of the tabs 221 reduces the likelihood of the tabs 221 burning and damaging the electrode sheet 20 beneath them, thereby improving the yield of the cylindrical battery 1000.
[0040] In this embodiment, by increasing the first height of a plurality of first lugs 231 in the winding direction of the wound battery cell 100, the downstream first tabs 231 can overlap with further upstream first tabs 231, thereby increasing the number of layers of first tabs 231 in the overlapping area and, consequently, increasing the thickness of the first tabs 231 in the overlapping area. When welding the current collector device 200 to the first tabs 231 in the overlapping area, the possibility of the first tabs 231 burning out and damaging the electrode sheet 20 beneath the first tabs 231 is further reduced, thereby further improving the yield of the cylindrical battery 1000.
[0041] By extending the first side edge 2311 diagonally toward the winding end in the direction from the active material coating portion 21 toward the tab portion 22, adjacent first tabs 231 can be overlapped after flattening to form overlapping areas, thereby increasing the number of overlapping areas. As a result, the number of weldable areas on the first tabs 231 is increased, which makes it easier to connect the current collector device 200 to the first tabs 231.
[0042] According to the wound battery cell 100 of the first embodiment of the present disclosure, the first height of the plurality of first tabs 231 is increased in the winding direction of the wound battery cell 100, thereby increasing the covering area of the tabs 221 on the electrode sheet 20, thereby increasing the overcurrent capacity of the wound battery cell 100, and also increasing the covering area of the flattened tabs 221 at the ends of the wound battery cell 100, thereby increasing the overcurrent capacity of the wound battery cell 100. In addition, the number of overlapping layers of the first tabs 231 is increased, thereby reducing the possibility that the first tabs 231 may burn out when the current collector device 200 is welded to the first tabs 231, causing damage to the electrode sheet 20 beneath the first tabs 231, and improving the quality of the cylindrical battery 1000. By extending diagonally along the first side, the number of overlapping areas between the first tabs 231 can be increased, thereby increasing the number of weldable areas on the first tabs 231, facilitating the connection between the current collector device 200 and the first tabs 231, and improving the manufacturing efficiency of the cylindrical battery 1000.
[0043] In some embodiments of this disclosure, the first height of the first tab 231 of a plurality of first tabs 231, the one closest to the winding start section 23 facing the reel hole 10, is 1 mm or less. For example, the first height of the first tab 231 closest to the winding start section 23 facing the reel hole 10 can be 1 mm, 0.5 mm, or 0.4 mm. Thus, the first height of the first tabs 231 located upstream in the winding direction is not excessively large. In the electrode sheet 20, the height of the other first tabs 231 in the first tab portion 223 is progressively increased based on the first height of the foremost first tab 231 in the winding direction. This ensures that the first tabs 231 located on the innermost circumference around the winding shaft hole 10 do not protrude into the reel hole 10 after being flattened, thereby enabling normal winding of the electrode sheet 20. During the product design process, the height of the foremost first tab 231 in the winding direction can be adjusted to meet more product design needs and reduce the difficulty of product design.
[0044] In some embodiments of this disclosure, as shown in Figures 4 and 6, the angle between the inclined extending direction of the first side edge 2311 and the longitudinal direction of the electrode sheet 20 (such as the left-right direction shown in Figure 4) is the first angle a. The first angle a of a plurality of first tabs 231 gradually increases along the winding direction. Therefore, it is advantageous to gradually increase the first height of a plurality of first tabs 231 in the winding direction, thereby saving material for the first tabs 231. At the same time, this reduces the difficulty of the process, thereby improving manufacturing efficiency and reducing manufacturing costs.
[0045] In some embodiments of this disclosure, as shown in Figure 4, the first angle a of the plurality of first tabs 231 increases linearly along the winding direction. Therefore, during product design, a gradual increase in the first height of the plurality of first tabs 231 can be achieved by adjusting the length of the hypotenuse of the first angle a in accordance with the increment of the first angle, thereby reducing the complexity of product design.
[0046] In some embodiments of this disclosure, the first angle a of the first tab 231 at the end closest to the winding start section 23 facing the reel hole 10 is 20° to 30°. For example, the first angle a of the first tab 231 at the end closest to the winding start section 23 facing the reel hole 10 can be 20°, 25°, or 30°. Thus, the first angle a of the first tab 231 at the end closest to the winding start section 23 facing the reel hole 10 can satisfy product design requirements. During the product design process, the first angle a of the first tab 231 at the end closest to the winding start section 23 facing the reel hole 10 can be adjusted, so that the size of the product can satisfy more design requirements and the difficulty of product design can be reduced.
[0047] In some embodiments of this disclosure, as shown in Figure 4, the lengths H of the first side edges 2311 of a plurality of first tabs 231 are equal. Thus, by increasing the first angle, the first height of the first tab 231 can be gradually increased, thereby reducing the difficulty of product design.
[0048] In some embodiments of this disclosure, as shown in Figures 4 and 6, the first tab 231 has a second side edge 2312 arranged opposite to the first side edge 2311 in the winding direction. The edge of the first tab 231 away from the active material coating portion 21 is the first side edge 2313, which is connected between the first side edge 2311 and the second side edge 2312. The first side edge 2313 is connected in an arc to both the first side edge 2311 and the second side edge 2312. During the product design process, parameters such as the size and relative angles of the first side edge 2311, the second side edge 2312, and the first side edge 2313 can be adjusted to meet product design requirements and reduce the difficulty of product design.
[0049] By connecting the first edge 2313 to the first side edge 2311 and the second side edge 2312 in an arc shape, the corners of the first tab 231 become smoother, thereby reducing burrs on the corners of the finished product of the first tab 231 during the manufacturing process, simplifying the manufacturing process and reducing the difficulty of manufacturing. Fewer burrs reduce the possibility of burrs falling off and causing a short circuit in the wound battery cell 100, thereby improving the reliability of the wound battery cell 100 during operation.
[0050] In some embodiments of this disclosure, as shown in Figures 4 and 6, the first side edge 2311 and the second side edge 2312 are arranged in parallel, the first end edge 2313 is arranged perpendicular to the first side edge 2311 and the second side edge 2312, or the first end edge 2313 extends parallel to the length direction of the electrode sheet 20. As the spatial relationship between the first end edge 2313 and both the first side edge 2311 and the second side edge 2312 changes, the overlap relationship between the first tabs 231 also changes. Therefore, during product design, the spatial relationship between the first end edge 2313 and both the first side edge 2311 and the second side edge 2312 can be selected according to the needs of the product design to meet more product design requirements.
[0051] In some embodiments of this disclosure, as shown in Figure 6, a second first tab 231 has a first height h1 that is greater by an increment z than the first height h of the first first tab 231, and a third first tab 231 has a first height h2 that is greater by the same increment z than the first height h1 of the second first tab 231. This configuration enables a gradual increase in the first height of multiple first tabs 231 along the winding direction. Furthermore, during product design, the design requirements can be directly met by adjusting the first height h and the linear height increment z of the foremost first tab 231 in the winding direction, thereby reducing the complexity of product design.
[0052] In some embodiments of this disclosure, the electrode sheet 20 includes a positive electrode sheet 20 and a negative electrode sheet 20, with a separator placed between them. In a direction perpendicular to the axis of the wound battery cell 100, the first height difference between the first tabs 231 on two adjacent turns of the electrode sheet 20 is equal to the combined thickness of the positive electrode sheet 20, the negative electrode sheet 20, and the two layers of separator. This configuration allows the positive electrode sheet 20, the negative electrode sheet 20, and the separator to be wound together during the winding process of the wound battery cell 100. After planarization, the first tabs 231 on the outer turns are aligned with the edges of the first tabs 231 on the inner turns, thereby achieving more uniform coverage of the first tabs 231 around the reel hole 10.
[0053] In some embodiments of this disclosure, the plurality of first tabs 231 of the first tab portion 223 are divided into a plurality of tab groups, and the plurality of tab groups are arranged sequentially along the winding direction. Each tab group contains at least one first tab 231, and the first heights of the plurality of first tabs 231 within each tab group are the same. Of two adjacent tab groups, the first height of the first tab 231 of the tab group located upstream in the winding direction is smaller than the first height of the first tab 231 of the tab group located downstream in the winding direction. As a result, it is possible to increase the first height of the plurality of first tabs 231 in the winding direction. In the manufacturing process, the difficulty of manufacturing can be reduced because the first heights of the first tabs 231 in a single tab group are the same. In the product design process, design requirements can be met by adjusting the first heights of the plurality of tab groups, and the difficulty of product design can be reduced because the number of parameters to be adjusted is relatively small.
[0054] In some embodiments of this disclosure, the distance between two adjacent tabs 221 in the winding direction is 0.05 mm to 2 mm. That is, the distance between the two closest side edges of two adjacent tabs 221 in the winding direction is 0.05 mm to 2 mm. For example, the distance between two adjacent tabs 221 can be 0.05 mm, 0.1 mm, or 2 mm. Therefore, the distance between two adjacent tabs 221 does not affect the bending of the tabs 221 into the reel hole 10, and the two adjacent tabs 221 can overlap. In the product design process, the distance between two adjacent tabs 221 can be adjusted to meet more product design requirements and reduce the difficulty of product design.
[0055] In some embodiments of this disclosure, as shown in Figure 1, the plurality of tabs 221 are bent toward the side where the reel hole 10 is located, and one end of the plurality of first tabs 231 facing the reel hole 10 is flush with the circumferential wall of the reel hole 10 or is located radially outward from the reel hole 10. Thus, the first tabs 231 do not affect the winding of the electrode sheet 20, and the covering area of the flattened first tabs 231 at the end of the wound battery cell 100 can be further increased, thereby further increasing the overcurrent withstand capability of the wound battery cell 100.
[0056] In some embodiments of this disclosure, the ends of one end of a plurality of first tabs 231 are aligned axially with respect to the wound battery cell 100. That is, the side edges of the plurality of first tabs 231 closest to the reel hole 10 are aligned in the thickness direction of the first tab 231, which means that the plurality of first tabs 231 overlap after flattening. This can increase the number of first tabs 231 in the overlapping area, thereby reducing the possibility of the first tabs 231 burning out during welding with the current collector device 200 and damaging the electrode sheet 20 beneath the first tabs 231, and improving the yield of the cylindrical battery 1000.
[0057] In some embodiments of the present disclosure, as shown in Figures 3 and 5, the electrode sheet 20 further includes a body section 24, the body section 24 connected to one end of the winding start section 23 away from the reel hole 10, and the tab portion 22 of the body section 24 is a second tab portion 224 including a plurality of second tabs 241. In the direction of the active material coating portion 21 facing the tab portion 22, the height dimension of the second tab portion 241 extending from the active material coating portion 21 in the direction of the active material coating portion 21 facing the tab portion 22 is the second height. That is, the distance between the outermost edge of the second tab portion 241 and the outer edge of the active material coating portion 21 in the direction of the active material coating portion 21 facing the tab portion 22 defines the second height, and for example, as shown in Figure 3, the distance C between the uppermost side of the second tab 241 and the upper edge of the active material coating portion 21 in the vertical direction forms the first height, and the second heights of multiple second tabs 241 are equal. During the tab winding process, the body section 24 is wound around the outer circumference of the winding start section 23. When the body section 24 begins winding, the second height of the first wound second tab 241 is less than or equal to the distance between the electrode sheet 20 corresponding to the first wound second tab 241 and the side edge of the reel hole 10. As the winding of the body section 24 progresses, the second tab 241 is then flattened and does not extend into the reel hole 10, and at this point the outer circumference of the reel hole 10 already covers the tab 221. By making the multiple second tabs 241 have equal second heights, the covering requirements for the tabs 221 at the ends of the wound battery cell 100 are met, while reducing process complexity and manufacturing costs.
[0058] In some embodiments of this disclosure, as shown in Figures 3 and 5, the side edge of the second tab 241 facing the winding start section 23 in the winding direction is a third side edge 2411. In the direction from the active material coating portion 21 toward the tab portion 22, the third side edge 2411 extends obliquely toward the winding end. This configuration gives the second tab 241 a longer length in the direction parallel to the electrode sheet 20. After the tab 221 is flattened, the overlap between the second tab 241 and the tab 221 from the previous turn can be increased. Furthermore, after two adjacent tabs 221 are flattened, the second tab 241 of the later tab 221 can be overlapped with the second tab 241 of the earlier tab 221. As a result, the overlap area between the tabs 221 is further increased, thereby increasing the weldable area on the tab 221 and facilitating welding of the current collector device 200 and the tab 221.
[0059] In some embodiments of the present disclosure, as shown in Figure 3, the tab portion 22 further includes a connection region 222, which is connected between the active material coating portion 21 and the plurality of tabs. The connection region 222 allows current to be transmitted from the active material coating portion 21 to the plurality of tabs 221, increasing the distance between the end of the wound battery cell 100 and the electrolyte, reducing the possibility of the current collector device 200 connected to the plurality of tabs 221 coming into contact with the electrolyte, and thus improving the reliability of the wound battery cell 100 during operation.
[0060] In some embodiments of this disclosure, the electrode sheet 20 is manufactured through a die-cutting process, which provides a high degree of automation and high manufacturing precision. As a result, manufacturing efficiency can be increased and the manufacturing precision of the electrode sheet 20 can also be improved.
[0061] According to the cylindrical battery 1000 of the second embodiment of this disclosure, the cylindrical battery 1000 comprises a wound battery cell 100 according to the first embodiment of this disclosure.
[0062] According to the cylindrical battery 1000 of the second embodiment of this disclosure, by providing the wound battery cell 100 according to the first embodiment of this disclosure, the overcurrent withstand capability of the wound battery cell 100 is increased, thereby improving the efficiency of the cylindrical battery 1000.
[0063] In some embodiments of the present disclosure, as shown in Figure 7, the cylindrical battery 1000 further includes a current collector 200, which is provided at the end of the wound battery cell 100 and connected to a tab 221. By providing the current collector 200, the current collector 200 enables current transmission with a plurality of tabs 221, thereby enabling the cylindrical battery 1000 to perform charging and discharging functions.
[0064] In some embodiments of this disclosure, the current collector device 200 is a current collector plate. The current collector plate is welded to the tab 221. The welded connection is easy to perform and enables electrical connection. This can improve production efficiency and ensure the functionality of the cylindrical battery 1000.
[0065] The following describes the manufacturing process of the cylindrical battery 1000 according to the embodiment of this disclosure.
[0066] First, the electrode sheet 20 is cut out according to the set parameters. The electrode sheet 20 is cut out according to the set parameters, and based on the set parameters, tabs 221 are formed on the upper part of the connection area 222 by cutting. Next, the electrode sheet 20 is wound. After the winding is complete, the tabs 221 are bent in advance. Subsequently, the tabs 221 are flattened. Finally, current collector plates are welded to the multiple flattened tabs 221, thereby completing the manufacturing process of the cylindrical battery 1000.
[0067] An electrical device according to an embodiment of the third aspect of the present disclosure comprises a cylindrical battery 1000 according to the above-described embodiment of the second aspect of the present disclosure.
[0068] By incorporating the cylindrical battery 1000 according to an embodiment of the second aspect of this disclosure, the electrical device according to an embodiment of the third aspect of this disclosure benefits from the increased efficiency of the cylindrical battery 1000, thereby improving the performance of the electrical device.
[0069] In the description of this application, terms such as “center,” “top,” “bottom,” “vertical,” “horizontal,” “top,” “bottom,” “inside,” “outside,” “axial,” “radial,” “circumferential,” and other directional or positional relationships are based solely on the directional or positional relationships shown in the accompanying drawings, for the convenience of describing this application and for the sake of simplification of the description, and do not imply or suggest that the devices or elements referred to have a particular orientation or need to be constructed and operated in a particular orientation, and should therefore not be construed as limitations of this specification.
[0070] In addition, the terms “first” and “second” are used for descriptive purposes only and should not be construed as suggesting or implying relative importance or the number of technical features shown. Therefore, features limited to “first” and “second” may explicitly or implicitly include one or more of these features. In this description, “multiple” means two or more unless otherwise specified.
[0071] In this application, unless otherwise specified and limited, terms such as “installation,” “connection,” “connection,” and “fixing” should be understood broadly, for example, they may be fixed connections, detachable connections, or integrated connections; they may be directly connected or indirectly connected through an intermediate medium; and they may be connections within two components or interaction relationships between two components. To those skilled in the art, the specific meanings of the above terms in this application can be understood on a case-by-case basis.
[0072] In this application, unless otherwise specified and limited, the first feature may be in direct contact with the second feature, either "above" or "below" the second feature, or the first and second features may be indirectly in contact through an intermediate medium. Furthermore, "above," "above," or "above" the second feature of the first feature may mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is horizontally taller than the second feature. The first feature may be located directly below or diagonally below the second feature, or simply that the first feature has a lower horizontal height than the second feature.
[0073] In this specification, any reference to the terms “one embodiment,” “several embodiments,” “example,” “specific example,” or “several examples” means that a particular function, structure, material, or property described in relation to an embodiment or example is included in at least one embodiment or example of this application. In this document, the abstract expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular functions, structures, materials, or properties described may be combined in any one or more embodiments or examples in an appropriate manner. In addition, those skilled in the art can combine different embodiments or examples and the functions of different embodiments or examples described herein without contradiction.
[0074] While embodiments of the present disclosure have been shown and described, those skilled in the art will understand that various modifications, alterations, substitutions, and variations are possible with respect to these embodiments without departing from the principles and objectives of the present disclosure, and the scope of the present disclosure is limited by the claims and their equivalents. [Explanation of Symbols]
[0075] 1000 Cylindrical Battery 100-wound battery cells 10 reel holes 20 electrode sheets 21 Active material coating section 22 Tab section 221 tabs 222 Connection Area 223 First tab section 224 Second tab section 23 Winding start section 231 First Tab 2311 First lateral edge 2312 Second lateral edge 2313 First edge 24 Main Section 241 Second tab 2411 Third lateral edge 200 Current collection devices
Claims
1. A wound battery cell (100) formed by a winding and having an internally defined reel hole (10), comprising an electrode sheet (20), the electrode sheet (20) comprising an active material coating portion (21) and a tab portion (22), the tab portion (22) being connected to one side of the active material coating portion (21) in the width direction, and the tab portion (22) comprising a plurality of tabs (221) arranged in the length direction of the electrode sheet (20), In the winding direction of the electrode sheet (20), one end facing the reel hole (10) is the winding start section (23), and in the winding direction of the electrode sheet (20), the other end opposite to the winding start section (23) is the winding end. The tab portion (22) of the winding start section (23) is a first tab portion (223), the first tab portion (223) comprises a plurality of first tabs (231), the edge of the side surface of the first tab (231) facing the reel hole (10) in the winding direction is a first side edge (2311), and in the direction from the active material coating portion (21) toward the tab portion (22), the first side edge (2311) extends diagonally toward the end of the winding, A wound battery cell (100) in which, in the direction of the active material coating portion (21) facing the tab portion (22), the height dimension of the first tab (231) extending from the active material coating portion (21) is a first height, and the first height of the plurality of first tabs (231) increases in the winding direction.
2. The wound battery cell (100) according to claim 1, wherein, of the plurality of first tabs (231), the first height of the first tab (231) closest to the end of the winding start section (23) facing the reel hole (10) is 1 mm or less.
3. The wound battery cell (100) according to claim 1, wherein the angle between the inclined extension direction of the first side edge (2311) and the longitudinal direction of the electrode sheet (20) is a first angle, and the first angle of the plurality of first tabs (231) gradually increases along the winding direction.
4. The wound battery cell (100) according to claim 3, wherein the first angle of the plurality of first tabs (231) increases linearly along the winding direction.
5. The wound battery cell (100) according to claim 3, wherein the first angle of the first tab (231) closest to the end of the end of the winding start section (23) facing the reel hole (10) is in the range of 20° to 30°.
6. The wound battery cell (100) according to claim 3, wherein the lengths of the first side edges (2311) of the plurality of first tabs (231) are equal.
7. The wound battery cell (100) according to claim 3, wherein the first tab (231) has a second side edge (2312) arranged opposite to the first side edge (2311) in the winding direction, and the end edge of the first tab (231) away from the active material coating portion (21) is the first end edge (2313), and the first end edge (2313) is connected between the first side edge (2311) and the second side edge (2312), and is connected in an arc shape to both the first side edge (2311) and the second side edge (2312).
8. The wound battery cell (100) according to claim 7, wherein the first side edge (2311) and the second side edge (2312) are arranged in parallel, the first end edge (2313) is arranged perpendicular to the first side edge (2311) and the second side edge (2312), or the first end edge (2313) extends parallel to the length direction of the electrode sheet (20).
9. A wound battery cell (100) according to any one of claims 1 to 8, wherein the first height of the plurality of first tabs (231) increases linearly along the winding direction.
10. The plurality of first tabs (231) of the first tab portion (223) are divided into a plurality of tab groups, the plurality of tab groups are arranged sequentially along the winding direction, each tab group comprises at least one first tab (231), and the first heights of the plurality of first tabs (231) within each tab group are the same. A wound battery cell (100) according to any one of claims 1 to 8, wherein, in two adjacent tab groups, the first height of the first tab (231) of the tab group located upstream in the winding direction is smaller than the first height of the first tab (231) of the tab group located downstream in the winding direction.
11. A wound battery cell (100) according to claim 1, wherein the distance between two adjacent tabs (221) in the winding direction is 0.05 mm to 2 mm.
12. The wound battery cell (100) according to any one of claims 1 to 11, wherein the plurality of tabs (221) are bent toward the side where the reel hole (10) is located, and one end of the plurality of first tabs (231) facing the reel hole (10) is flush with the peripheral wall of the reel hole (10) or is located radially outward from the reel hole (10).
13. The wound battery cell (100) according to claim 12, wherein the ends of the plurality of first tabs (231) at one end are aligned in the axial direction of the wound battery cell (100).
14. A wound battery cell (100) according to any one of claims 1 to 13, wherein the electrode sheet (20) further comprises a body section (24), the body section (24) is connected to one end of the winding start section (23) away from the reel hole (10), the tab (22) of the body section (24) is a second tab portion (224), the second tab portion (224) comprises a plurality of second tabs (241), the height dimension of the second tabs (241) extending from the active material coating portion (21) in the direction of the active material coating portion (21) facing the tab portion (22) is a second height, and the second heights of the plurality of second tabs (241) are equal.
15. The wound battery cell (100) according to claim 14, wherein the edge of the side surface of the second tab (241) facing the winding start section (23) in the winding direction is the third side edge (2411), and the third side edge (2411) extends diagonally toward the winding end in the direction from the active material coating portion (21) toward the tab portion (22).
16. The wound battery cell (100) according to any one of claims 1 to 15, wherein the tab portion (22) further comprises a connection region (222), and the connection region (222) is connected between the active material coating portion (21) and the plurality of tabs (221).
17. A cylindrical battery (1000) comprising a wound battery cell (100) according to any one of claims 1 to 16.
18. An electrical device comprising a cylindrical battery (1000) as described in claim 17.