Long pole piece and lithium battery roll core

Abstract

The utility model provides a kind of long tab and lithium battery roll core, long tab includes current collector and the active material layer of coating in at least one side of current collector, long tab length direction has multiple winding area for winding to form bending section, at least part winding area is provided with cutting structure, cutting structure at least extends along the length direction of tab;Cutting structure includes the first cutting section being arranged on current collector and the second cutting section being arranged on active material layer, for any one winding area being provided with cutting structure, the extension length of second cutting section is not less than the extension length of first cutting section, and first cutting section is correspondingly provided with second cutting section at any position in long tab length direction. By the technical scheme provided by the utility model, the problem that crack on long tab at bending section of lithium battery roll core is easy to extend under the action of winding force and expansion stress, causing the long tab at this place to break.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and more specifically, to a long electrode sheet and a lithium battery core. Background Technology

[0002] Currently, lithium battery cells are typically manufactured using a winding process, which generally involves stacking long electrode sheets and separators and then winding them together as a whole.

[0003] During the processing of long electrode sheets, cracks may be generated on their current collectors. Cracks on the current collectors at the long electrode sheets corresponding to the curved sections of wound lithium battery cores are easily extended by the winding force and expansion stress, leading to tearing. Especially when lithium battery cores are subjected to drop and vibration tests, the small cracks generated can gradually expand, causing the current collectors at the entire curved section or even the long electrode sheets to break and fail. Utility Model Content

[0004] This invention provides a long electrode sheet and a lithium battery cell to solve the problem that cracks on the long electrode sheet at the bending section of the lithium battery core are prone to extend under the action of winding force and expansion stress, leading to the breakage of the long electrode sheet at that location.

[0005] To address the aforementioned problems, according to one aspect of this utility model, a long electrode sheet is provided for winding to form a lithium battery core with a curved section. The long electrode sheet includes a current collector and an active material layer coated on at least one side of the current collector. The long electrode sheet has multiple winding areas along its length for winding to form the curved section. At least some of the winding areas are provided with a cutting structure, which extends at least along the length of the long electrode sheet. The cutting structure includes a first cutting segment disposed on the current collector and a second cutting segment disposed on the active material layer. For any winding area with a cutting structure, the extension length of the second cutting segment is not less than the extension length of the first cutting segment, and the first cutting segment is correspondingly provided with the second cutting segment at any position along the length of the long electrode sheet.

[0006] Furthermore, for any winding area with a cutting structure, the first cutting segment and the second cutting segment are at least partially aligned in the thickness direction of the long electrode sheet.

[0007] Furthermore, for any winding area with a cutting structure, the first cutting segment and the second cutting segment are spaced apart in the thickness direction of the long electrode sheet.

[0008] Furthermore, for any winding area with a cutting structure, in the length direction of the composite, the number of groups of first cutting segments is A, 1≤A≤5, at least one first cutting segment forms a group, and when A≥2, multiple first cutting segments are distributed at intervals along the width direction and / or the length direction of the composite, and at least some of the first cutting segments are the same; in the length direction of the composite, the number of groups of second cutting segments is B, 1≤B≤5, at least one second cutting segment forms a group, and when B≥2, multiple second cutting segments are distributed at intervals along the width direction and / or the length direction of the composite, and at least some of the second cutting segments are the same.

[0009] Furthermore, multiple first cutting segments are aligned with multiple second cutting segments.

[0010] Furthermore, at least two first cut segments form a group, and multiple first cut segments in the same group are spaced apart along the width direction of the composite, and / or, at least two second cut segments form a group, and multiple second cut segments in the same group are spaced apart along the width direction of the composite.

[0011] Furthermore, the first cutting segment is a kerf without a cutting area, and the second cutting segment is a cut with a cutting area and / or a kerf without a cutting area.

[0012] Furthermore, the cut is a strip-shaped opening extending along the length direction of the long electrode sheet; the width of the cut is constant; or, the width of the cut at least partially varies along the length direction of the winding area.

[0013] Furthermore, the slit extends in a straight line, bends, or meanders along the length of the long electrode sheet; the cut extends in a straight line, bends, or meanders along the length of the long electrode sheet.

[0014] Furthermore, according to another aspect of the present invention, the present invention provides a lithium battery core, the lithium battery core including a tab and a composite formed by stacking a separator and the aforementioned long electrode sheet, the composite being wound to form a lithium battery core, multiple winding areas corresponding to multiple curved sections, the tab being disposed on the long electrode sheet and located in the middle region of the lithium battery core.

[0015] The present invention provides a long electrode sheet for winding to form a lithium battery core with a curved section. The long electrode sheet includes a current collector and an active material layer coated on at least one side of the current collector. The long electrode sheet has multiple winding areas along its length for winding to form the curved section. At least some of the winding areas are provided with a cutting structure, which extends at least along the length of the long electrode sheet. The cutting structure includes a first cutting segment disposed on the current collector and a second cutting segment disposed on the active material layer. For any winding area with a cutting structure, the extension length of the second cutting segment is not less than the extension length of the first cutting segment, and the first cutting segment is provided with a corresponding second cutting segment at any position along the length of the long electrode sheet.

[0016] This solution, through the cutting structure, can stop the extension of cracks on the long electrode sheet in the winding area used to form the bending section. Specifically, it mainly stops the extension of cracks in the current collector of the long electrode sheet (including positive and negative long electrode sheets) in the bending section during the winding or use of the lithium battery core, which is easily affected by the winding force and the expansion stress during use. This prevents the cracks from continuing to extend along the width direction of the long electrode sheet, causing the long electrode sheet to break, which in turn affects the performance of the lithium battery core or causes damage to the lithium battery core, thus ensuring the reliability and stability of the long electrode sheet in use. On the other hand, by distinguishing the cutting structures and defining the lengths and correspondences of the first and second cutting segments, it is beneficial to further ensure the reliability and stability of the long electrode sheet. Specifically, the first cutting structure stops the extension of cracks on the current collector, preventing the current collector from breaking. The second cutting structure is used to stop cracks in the active material layer that are also prone to breakage when the cracks on the current collector extend. This achieves both anti-breakage design for the current collector and anti-breakage design for the active material layer, thereby avoiding the situation where the extension of cracks in the current collector is stopped but the active material layer still has the risk of breakage, thus improving the reliability of crack stopping and preventing long electrode sheet breakage. Attached Figure Description

[0017] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments and descriptions of this utility model are used to explain this utility model and do not constitute an undue limitation thereof. In the drawings:

[0018] Figure 1 A schematic diagram of the structure of the long electrode sheet provided in an embodiment of the present invention is shown;

[0019] Figure 2 A schematic diagram of the structure of one winding region of a long electrode sheet provided in another embodiment of the present invention is shown;

[0020] Figure 3A schematic diagram of the structure of a lithium battery core provided in another embodiment of the present invention is shown;

[0021] Figure 4 It shows Figure 3 The main view;

[0022] Figure 5 It shows Figure 4 AA section view;

[0023] Figure 6 It shows Figure 4 BB cross-sectional view.

[0024] The above figures include the following reference numerals:

[0025] 1. Composite; 01. Winding area;

[0026] 10. Long electrode sheet; 101. Cutting structure;

[0027] 20. Diaphragm;

[0028] 30. Pole tabs. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0030] like Figures 1 to 6 As shown, an embodiment of the present invention provides a long electrode 10 for winding to form a lithium battery core with a curved section. The long electrode 10 includes a current collector and an active material layer coated on at least one side of the current collector. The long electrode 10 has a plurality of winding regions 01 for winding to form the curved section in the length direction. At least some of the winding regions 01 are provided with a cutting structure 101. The cutting structure 101 extends at least along the length direction of the long electrode 10. The cutting structure 101 includes a first cutting segment disposed on the current collector and a second cutting segment disposed on the active material layer. For any winding region 01 provided with the cutting structure 101, the extension length of the second cutting segment is not less than the extension length of the first cutting segment, and the first cutting segment is provided with a corresponding second cutting segment at any position in the length direction of the long electrode 10.

[0031] In this embodiment, the cutting structure 101 can stop the extension of cracks on the long electrode 10 at the winding area 01 used to form the bending section. Specifically, it mainly stops the extension of cracks in the current collector of the long electrode 10 (including the positive electrode and the negative electrode) at the bending section during the winding or use of the lithium battery core, which is easily affected by the winding force and the expansion stress during use. This prevents the cracks from continuing to extend along the width direction of the long electrode 10, causing the long electrode 10 to break, thereby affecting the performance of the lithium battery core or causing damage to the lithium battery core, and ensuring the reliability and stability of the long electrode 10 in use. On the other hand, by distinguishing the cutting structure 101 and defining the length and correspondence of the first and second cutting segments, it is beneficial to further ensure the reliability and stability of the long electrode 10. Specifically, the first cutting structure 101 stops the extension of cracks on the current collector, preventing the current collector from breaking. The second cutting structure 101 is used to stop cracks that appear in the active material layer corresponding to the cracks on the current collector when they extend, which also have a tendency to break. This achieves both anti-breakage design for the current collector and anti-breakage design for the active material layer, thereby avoiding the situation where the extension of cracks in the current collector is stopped but the active material layer still has a risk of breakage, improving the reliability of crack stopping and preventing the long electrode 10 from breaking.

[0032] It should be noted that the cracks on the current collector of the long electrode 10 (including the positive and negative electrode sheets) at the winding area 01 extend along the width direction of the composite 1 under the action of winding force and expansion stress during use. During its extension and fracture process, corresponding cracks are also likely to appear on the corresponding active material layer, making the long electrode 10 prone to fracture. After the cutting structure 101 is set, the cracks will not continue to extend after reaching the cutting structure 101, thus preventing the long electrode 10 from breaking due to the continued extension of the cracks. The long electrode 10 is wound to form multiple curved sections (formed by the winding area 01) and multiple straight sections (formed by other parts besides the winding area 01). The long electrode 10 in both the straight and curved sections may have cracks left over from processing. However, since the long electrode 10 in the curved section is also affected by the bending force, the cracks on it are more likely to extend than those in the straight section. That is, the long electrode 10 in the curved section is more likely to break than the long electrode 10 in the straight section. The cracks on the long electrode 10 in the straight section are only prone to extension under the action of expansion stress when the lithium battery core is used, and the possibility of it breaking is low. Therefore, it is not necessary to deliberately set the cutting structure 101. The cutting structure 101 can be set only on the long electrode 10 in the curved section. At the same time, this setting can also avoid the situation where too many cutting structures affect the performance and structural strength of the lithium battery core.

[0033] Among them, for the same winding area 01, the number, setting position, correspondence, and extension of the first and second cutting segments can be adaptively adjusted according to the actual situation.

[0034] In some embodiments, for any winding area 01 provided with the cutting structure 101, the first cutting segment and the second cutting segment are at least partially aligned in the thickness direction of the long electrode sheet 10. Alternatively, in other embodiments not shown, for any winding area 01 provided with the cutting structure 101, the first cutting segment and the second cutting segment are spaced apart in pairs in the thickness direction of the long electrode sheet 10. This arrangement facilitates the operator in setting the first and second cutting segments according to the actual extension of the cracks, avoiding situations where the crack positions of the current collector and the active material layer are not completely aligned in the thickness direction of the winding area 01, making it impossible to stop the extension of all cracks using the aligned first and second cutting segments. This improves the reliability of crack extension prevention.

[0035] Furthermore, for any winding area 01 equipped with a cutting structure 101, in the length direction of the composite 1, the number of groups of first cutting segments is A, 1≤A≤5, with at least one first cutting segment forming a group. When A≥2, multiple first cutting segments are distributed at intervals along the width direction and / or the length direction of the composite 1, with at least some first cutting segments being the same. In the length direction of the composite 1, the number of groups of second cutting segments is B, 1≤B≤5, with at least one second cutting segment forming a group. When B≥2, multiple second cutting segments are distributed at intervals along the width direction and / or the length direction of the composite 1, with at least some second cutting segments being the same. This arrangement avoids the situation where the number of groups of first and second cutting segments in the length direction of the composite 1 is too large, which would affect the functionality and structural strength of the long electrode 10 at the winding area 01. At the same time, it helps to reduce the formation of ineffective cutting structures 101 and makes the prevention of cracks more targeted.

[0036] In this embodiment, multiple first cutting segments and multiple second cutting segments are aligned one-to-one, facilitating the simultaneous preparation of the first and second cutting segments and improving the preparation efficiency of the cutting structure 101. Figures 1 to 2 In the embodiment shown, each winding area 01 is provided with a set of opposing first and second cutting segments. Each set of first cutting segments includes two first cutting segments, and each set of second cutting segments includes two second cutting segments. The two first cutting segments and the two second cutting segments correspond one-to-one and are identical. Both the first and second cutting segments extend along the length direction of the composite 1 and extend to both ends of the winding area 01 where they are located. This arrangement facilitates coverage of the winding area 01 along its length, thus preventing the extension of some cracks from being unstoppable.

[0037] Preferably, two first cutting segments are disposed on both sides of all cracks on the winding area 01, and two second cutting segments are disposed similarly, so as to ensure that the cracks do not extend along the width direction of the composite 1 to both sides of the composite 1 to form tear openings.

[0038] It is understood that at least two first cut segments form a group, and multiple first cut segments in the same group are spaced apart along the width direction of the composite 1, and / or at least two second cut segments form a group, and multiple second cut segments in the same group are spaced apart along the width direction of the composite 1. With this configuration, the number of groups of first cut segments and the number of groups of second cut segments are greater than or equal to 2. Although this is more difficult to manufacture than when the number of groups is 1, it reduces the formation of ineffective cut structures 101 (i.e., parts that cannot stop the extension of cracks), making the crack prevention more targeted. However, if each group includes a large number of first and second cut segments, it can easily lead to a decrease in the structural strength and performance of the long electrode 10 at the winding region 01. Therefore, it is preferable that each group of first cut segments includes two to three first cut segments, and the same applies to the second cut segments.

[0039] Optionally, in other embodiments not shown in the figures, for any winding region 01, the projections of the plurality of first cut segments on it onto a plane perpendicular to the width direction of the long electrode 10 at least partially overlap. The total extension length of the projections of the plurality of first cut segments onto the plane perpendicular to the width direction of the long electrode 10 is the maximum effective coverage length of the plurality of first cut segments in the extension direction of the current collector, and this maximum effective coverage length is preferably equal to the arc length of the current collector. Similarly, for any winding region 01, the projections of the plurality of second cut segments on it onto a plane perpendicular to the width direction of the long electrode 10 at least partially overlap. The total extension length of the projections of the plurality of second cut segments onto the plane perpendicular to the width direction of the long electrode 10 is the maximum effective coverage length of the plurality of second cut segments in the extension direction of the active material layer, and this maximum effective coverage length is preferably equal to the arc length of the active material layer. Taking the first cutting segment as an example, there are four first cutting segments. These four segments are distributed along the length direction of the long electrode sheet 10 and spaced apart along the width direction of the long electrode sheet 10. Along the length direction of the long electrode sheet 10, the projections of any two adjacent first cutting segments onto a plane perpendicular to the width direction of the long electrode sheet 10 at least partially overlap. This arrangement ensures coverage and prevents the spread of cracks at different locations along the length direction of the long electrode sheet 10. It also helps reduce the length design of each first cutting segment, avoiding the situation where there are large ineffective cutting segments.

[0040] In contrast to the above embodiment, in another embodiment (not shown), the maximum effective coverage length can also be segmented and less than the length of the winding area 01, as long as the effect of stopping the extension of the crack is guaranteed. For example... Figure 2As shown, this embodiment describes the design of the cutting structure 101 on one of the winding areas 01. It has three sets of cutting structures 101 (each cutting structure 101 includes an identical first cutting segment and a second cutting segment that are directly opposite each other). Each set consists of two cutting structures 101, meaning there are six identical cutting structures 101 arranged in three columns and two rows. The effective coverage length is the sum of the lengths of each set of cutting structures 101. It should be noted that in this embodiment, the spacing between adjacent sets of cutting structures 101 should not be too small to avoid cracks extending through that area.

[0041] Preferably, the first cutting segment is a slit without a cutting area, and the second cutting segment is a cut with a cutting area and / or a slit without a cutting area. In this embodiment, the first and second cutting segments are opposite slits, further improving the processing efficiency of the cutting structure 101. In other embodiments not shown, the second cutting segment is a cut with a cutting area. The cut has a better effect on stopping the extension of cracks than the slit, but its processing is more difficult than the slit and may have a greater impact on the structural strength or performance of the long electrode 10 at the winding area 01. In this embodiment, the slit extends linearly along the length direction of the long electrode 10, which facilitates rapid processing of the slit. In other embodiments not shown, the slit may also extend in a bent or meandering manner along the length direction of the long electrode 10 to increase the actual stopping length of the slit. Among them, zigzag extension and meandering extension are not exactly the same. Zigzag extension emphasizes that there are obvious bending and turning points in the extension process, while meandering extension focuses more on the object presenting a winding and continuous state without obvious turning points, but the overall line is relatively curved.

[0042] Furthermore, in other embodiments not shown in the figures, the second cutting segment is at least partially a slit with a cutting area, the slit being a strip-shaped opening extending along the length direction of the long electrode 10; the width of the slit is constant; or, the width of the slit at least partially changes gradually along the length direction of the winding area 01. This arrangement facilitates the operator in designing slits of suitable shape and size according to actual conditions, ensuring the reliability of stopping the extension of cracks at different positions along the length direction of the long electrode 10 in the winding area 01. The slit can also extend straight, bend, or meander along the length direction of the long electrode 10, which is beneficial for balancing processing convenience and actual stopping length.

[0043] Preferably, the design of the cutting structures 101 on the multiple winding areas 01 can be different, the same, or not completely identical. The design of the cutting structures 101 on each winding area 01 is not limited to this embodiment. For example, in an embodiment not shown in the figure, the first cutting segment is a plurality of straight segments distributed along the length and width directions of the long electrode sheet 10, and the second cutting segment can be a continuous wavy segment. The continuous wavy segment can extend at least to both ends of the overall length formed by the plurality of straight segments in the length direction of the long electrode sheet 10. The design of the cutting structures 101 on each winding area 01 can be adaptively adjusted according to the actual situation, and examples are not given here.

[0044] Specifically, such as Figures 3 to 6 As shown, another embodiment of this utility model provides a lithium battery core. The lithium battery core includes a tab 30 and a composite 1 formed by stacking a separator 20 and the aforementioned long electrode sheet. The composite 1 is wound to form the lithium battery core, and multiple winding areas 01 corresponding to multiple curved segments are formed. The tab 30 is disposed on the long electrode sheet and located in the middle region of the lithium battery core. The lithium battery core further includes the tab 30. Preferably, the tab 30 is disposed on the long electrode sheet 10 and located in the middle region of the lithium battery core. Compared to the conventional structure where the tabs 30 (first tab and second tab) are located at one end of the long electrode 10, the centrally positioned tabs 30 in this embodiment reduce the battery's internal resistance. In this centrally positioned structure, electrons diffuse from the middle of the tabs 30 to both ends, shortening the current path and reducing the battery's internal resistance. Furthermore, with the tabs 30 centrally positioned, its rate performance is close to that of batteries using a stacked process. The performance difference is not significant at low discharge rates, but its advantages are evident at high discharge rates, supporting larger charge and discharge currents, enabling fast charging and high-power discharge, and meeting the needs of some high-rate electrical devices. Moreover, due to the reduced internal resistance, less heat is generated during high-rate charge and discharge, resulting in a smaller temperature rise and thus improving battery safety and lifespan. On the other hand, this structure is relatively regular. When the battery is subjected to external impact, the tab 30 is located in the middle, resulting in better stress distribution. Compared to a structure where the tab 30 is located on one side, the centrally located tab 30 structure is more stable and less prone to short circuits, fires, or other problems caused by deformation or displacement, thus reducing the risk of cell bulging, combustion, or even explosion. Furthermore, the centrally located tab 30 effectively reduces the area of ​​the empty foil region at the tab 30 welding point, thereby effectively improving the battery's energy density.

[0045] In summary, this utility model provides a lithium battery core that improves the performance of the lithium battery cell by centrally positioning the tabs. The cutting structure 101 can stop the extension of cracks in the long electrode 10 (including positive and negative long electrode) at the bending section, preventing the cracks from continuing to extend along the width direction of the composite 1 and causing the composite 1 to break, thereby affecting the performance of the lithium battery core or causing damage to the lithium battery core, thus ensuring the reliability and stability of the lithium battery core.

[0046] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0047] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0048] In the description of this utility model, it should be understood that the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours of each component itself.

[0049] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0050] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0051] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A long electrode sheet for winding to form a lithium battery core having a curved section, the long electrode sheet comprising a current collector and an active material layer coated on at least one side of the current collector, characterized in that, The long electrode has multiple winding areas (01) along its length for winding to form the curved section. At least a portion of the winding areas (01) are provided with a cutting structure (101). The cutting structure (101) extends at least along the length of the long electrode. The cutting structure (101) includes a first cutting segment disposed on the current collector and a second cutting segment disposed on the active material layer. For any winding area (01) provided with the cutting structure (101), the extension length of the second cutting segment is not less than the extension length of the first cutting segment, and the first cutting segment is provided with the second cutting segment at any position along the length of the long electrode.

2. The long electrode sheet according to claim 1, characterized in that, For any winding region (01) provided with the cutting structure (101), in the thickness direction of the long electrode sheet, the first cutting segment and the second cutting segment are at least partially opposite each other.

3. The long electrode sheet according to claim 1, characterized in that, For any winding area (01) provided with the cutting structure (101), the first cutting segment and the second cutting segment are spaced apart in the thickness direction of the long electrode sheet.

4. The long electrode sheet according to claim 1, characterized in that, For any winding area (01) provided with the cutting structure (101), In the length direction of the long electrode sheet, the number of groups of the first cut segments is A, 1≤A≤5, at least one of the first cut segments forms a group, and when A≥2, multiple first cut segments are distributed at intervals along the width direction and / or the length direction of the long electrode sheet, and at least some of the first cut segments are the same. In the length direction of the long electrode sheet, the number of groups of the second cut segments is B, 1≤B≤5, at least one of the second cut segments forms a group, and when B≥2, multiple second cut segments are distributed at intervals along the width direction and / or the length direction of the long electrode sheet, and at least some of the second cut segments are the same.

5. The long electrode sheet according to claim 4, characterized in that, Multiple first cutting segments are directly opposite multiple second cutting segments.

6. The long electrode sheet according to claim 5, characterized in that, At least two of the first cut segments form a group, and multiple first cut segments in the same group are spaced apart along the width direction of the long electrode sheet, and / or at least two of the second cut segments form a group, and multiple second cut segments in the same group are spaced apart along the width direction of the long electrode sheet.

7. The long electrode sheet according to claim 1, characterized in that, The first cutting segment is a slit without a cutting area, and the second cutting segment is a cut with a cutting area and / or a slit without a cutting area.

8. The long electrode sheet according to claim 7, characterized in that, The cut is a strip-shaped opening extending along the length direction of the long electrode sheet; The width of the cut is constant; Alternatively, the width of the cut may at least partially change in the length direction of the winding area (01).

9. The long electrode sheet according to claim 7, characterized in that, The slit extends in a straight line, bends, or meanders along the length of the long electrode sheet. The cut extends in a straight line, bends, or meanders along the length of the long electrode.

10. A lithium battery core, characterized in that, The lithium battery core includes a tab (30) and a composite (1) formed by stacking a separator (20) and a long electrode sheet according to any one of claims 1 to 9. The composite (1) is wound to form the lithium battery core. A plurality of the winding areas (01) are correspondingly formed with a plurality of the bending segments. The tab (30) is disposed on the long electrode sheet and located in the middle region of the lithium battery core.

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