Winded cell structure and battery

Abstract

Winded cell structure (100), characterized by a wound first electrode sheet (110), a separator and a second electrode sheet (120), wherein the separator is arranged between the adjacent first electrode sheet (110) and the second electrode sheet (120), and wherein the first electrode sheet (110) and the second electrode sheet (120) have opposite polarities; the second electrode sheet (120) is provided with a second collector (121), a second active material layer (122) formed on at least one surface of the second collector (121) and a second flag (123), while the first electrode sheet (110) is provided with a first collector (111), a first active material layer (112) formed on at least one surface of the first collector (111) and a first flag (113); a weld groove (130) for the first flag (113) is provided on the first active material layer (112), wherein the first flag (113) is welded to the first collector (111) within the weld groove (130); a first receiving opening (1221) is formed on the second active material layer (122), which is opposite the weld groove (130); and the bottom of the first receiving opening (1221) has several grooves (180) which extend along the longitudinal direction of the first receiving opening (1221).

Description

Technical area

[0001] The present electrical utility model relates to the technical field of batteries, in particular a wound cell structure and a battery. State of the art

[0002] With the advent of the 5G era and the rapid development of lithium-ion battery technology, increasingly stringent requirements are being placed on the energy density, fast-charging capability, and charge and discharge C-coefficients of lithium-ion batteries. Fast-charging lithium-ion batteries have become a development trend in the field of consumer lithium-ion batteries.

[0003] Currently, the central arrangement of the tabs in lithium-ion batteries is increasingly being used to improve the fast-charging performance of batteries. The tabs are welded in the center of the electrode sheet, which can effectively reduce the internal resistance of the battery to achieve a fast-charging effect.

[0004] However, the current solution requires the application of a protective adhesive film at the tab's weld points to prevent safety issues that could be caused by the separator being punctured by the tab's weld points. However, this results in an unnecessarily increased battery thickness at the tab's weld points due to the raised areas created by the tab and the protective adhesive film. Brief summary of the utility model

[0005] The present embodiment of the utility model provides a wound cell structure and a battery. On the one hand, the unusable thickness of the electrode sheet can be reduced, thereby reducing the unusable thickness of the wound cell and increasing the energy density of the lithium-ion battery. On the other hand, safety risks can be reduced and the wetting efficiency of the electrode sheet formed with a first receiving opening with electrolyte can be improved.

[0006] The utility model comprises a wound cell structure having a wound first electrode sheet, a separator, and a second electrode sheet. The separator is arranged between the first and second electrode sheets, which have opposite polarities. The second electrode sheet is provided with a second collector, a second active material layer formed on at least one surface of the second collector, and a second lug. The first electrode sheet has a first collector, a first active material layer formed on at least one surface of the first collector, and a first lug. A welding groove for the first lug is formed in the first active material layer, the first lug being welded to the first collector in the welding groove. The second active material layer has a first receiving opening opposite the welding groove.At the bottom of the first receiving opening, a plurality of recesses are formed which extend along the longitudinal direction of the first receiving opening.

[0007] The design of the first receiving opening allows the thickness of the tab to be integrated into the active material layer of the electrode sheet. This reduces the unusable thickness of the electrode sheet, which in turn reduces the unusable thickness of the wound cell and increases the energy density of the lithium-ion battery. This improves the space utilization and the operating time of electronic devices. In addition, the recesses at the bottom of the first receiving opening increase the friction between the second protective adhesive film and the bottom of the receiving opening, thereby minimizing the risk of the protective adhesive film slipping or peeling off. Furthermore, the recesses in the first receiving opening are spatially connected to the recesses on the surface of the second electrode sheet, allowing a portion of the electrolyte to flow through the recesses in the first receiving opening into the recesses on the surface of the second electrode sheet.This improves the wetting efficiency of the electrode sheet formed with a first receiving opening with electrolyte.

[0008] In some optional embodiments, the depth of the grooves is greater than or equal to 3 µm and less than or equal to 15 µm; and / or the width of the grooves is greater than or equal to 20 µm and less than or equal to 150 µm; and / or the distance between two adjacent grooves is greater than or equal to 0.5 mm and less than or equal to 2 mm.

[0009] It should be noted that these settings may increase the frictional force between the second protective adhesive film and the bottom of the first receiving opening to avoid safety hazards caused by the second protective adhesive film slipping and falling off.

[0010] In some optional embodiments, the upper edge of the first receiving opening is flush with the upper edge of the second active material layer; or a gap is arranged between the upper edge of the first receiving opening and the upper edge of the second active material layer, wherein the size of the gap is greater than or equal to 0.5 mm and less than or equal to 2 mm.

[0011] It should be noted that a flush upper edge of the first receiving opening with the upper edge of the cathodic active material layer further promotes the reduction of the unusable thickness of the wound cell.

[0012] In some optional embodiments, the width A of the first receiving opening and the width B of the first tab satisfy the relationship: B + 3 mm < A < B + 6 mm; and / or the length D of the first receiving opening and the length E of the welding end of the first tab satisfy the relationship: E + 2 mm < D < E + 5 mm.

[0013] It should be noted that these settings can increase production efficiency and prevent the first tab from being unable to insert into the first receiving opening due to production variations and overlapping with its edge, resulting in additional thickness and ultimately reducing the energy density of the lithium-ion battery.

[0014] In some optional embodiments, a second protective adhesive film is applied in the first receiving opening.

[0015] In some optional embodiments, the width C of the second protective adhesive film and the width A of the first receiving opening satisfy the relationship: A - 4 mm < C < A - 1 mm, and along the width direction of the second protective adhesive film, the distance between its edge and the edge of the first receiving opening is greater than 0.5 mm; and / or the length F of the second protective adhesive film and the length D of the first receiving opening satisfy the relationship: D - 4 mm < F < D + 2 mm, and the bottom edge of the second protective adhesive film is away from the bottom edge of the first receiving opening by more than 0.5 mm.

[0016] It should be noted that the second protective adhesive film in the first receiving opening can prevent rough exposed areas at the bottom of the first receiving opening from friction with the separator, producing particles that puncture the separator and cause a short circuit between the anode and the cathode.

[0017] In some optional embodiments, a second receiving opening is formed on the second active material layer, which is connected to the first receiving opening. The second receiving opening extends in a direction away from the second active material layer, and the second protective adhesive film serves to cover the second receiving opening.

[0018] It should be noted that the second receiving opening is designed to at least partially receive the first tab in order to reduce the thickness of the wound cell and improve the space utilization and energy density of the battery.

[0019] In some optional embodiments, the relationship between the width G of the second receiving opening and the width B of the first tab satisfies: B+0 mm < G < B+2 mm, wherein the projection of the first tab in the width direction of the first tab lies within the second receiving opening; and / or the relationship between the length H of the second receiving opening and the total length P of the weld points of the first tab satisfies: P+1 mm < H < P+4 mm, wherein the projection of the weld points of the first tab in the longitudinal direction of the weld points lies within the second receiving opening.

[0020] It should be noted that this setting has the advantage of increasing production efficiency and preventing the first tab from being embedded into the second receiving opening due to production fluctuations. This would result in overlap with the edges of the second receiving opening, causing additional thickness and ultimately increasing the thickness of the wound cell and reducing the energy density of the lithium-ion battery.

[0021] In some optional embodiments, the length of the welding portion of the first flag is greater than or equal to 5 mm and less than or equal to 35 mm; and / or the width of the first flag is greater than or equal to 4 mm and less than or equal to 15 mm; and / or the width of the welding spots of the first flag is smaller than the width of the first flag, and the difference Z between the width of the welding spots and the width of the first flag satisfies: 0.5 mm ≤ Z ≤ 2 mm; and / or in the width direction of the welding spots of the first flag, the distance between the welding spots and the edge of the first flag is more than 0.5 mm.

[0022] This setting is intended to prevent the welding points of the first tab from deviating when welding to the first collector, which would lead to damage to the first collector, ultimately to welding defects and an increase in the internal resistance of the cell.

[0023] In some optional embodiments, a first protective adhesive film is applied to the welding groove on the side of the first electrode sheet, covering the first receiving opening; the distance between the edge of the first protective adhesive film and the edge of the first receiving opening is more than 1 mm and less than 5 mm.

[0024] It should be noted that the surface of the first protective adhesive film covers the surface of the welding groove, with the overlap area on the second electrode sheet being within the projection of the first receiving opening.

[0025] In some optional embodiments, the weld groove is a double-sided weld groove, and a third protective adhesive film is applied to the weld groove on the other side of the first electrode sheet. The third protective adhesive film and the first protective adhesive film are each located on opposite sides of the first electrode sheet; the total height of the weld spots of the first tab is greater than or equal to 10 µm and less than or equal to 65 µm.

[0026] In some optional embodiments, a first receiving opening is formed on one side of the second active material layer of the second electrode sheet, and a third receiving opening is formed on the other side of the second active material layer of the second electrode sheet; a fourth protective adhesive film is arranged in the third receiving opening; and a fourth receiving opening is further formed on the other side of the second active material layer of the second electrode sheet, which fourth receiving opening is connected to the third receiving opening. The fourth receiving opening is arranged in a direction leading away from the second active material layer, and the fourth protective adhesive film serves to cover the fourth receiving opening.

[0027] It should be noted that the fourth receiving opening is designed such that the first tab can be at least partially embedded in the fourth receiving opening, whereby the thickness of the wound cell can be reduced to a certain extent, which in turn improves the space utilization and energy density of the battery.

[0028] In some optional embodiments, the depth H1 of the first receiving opening, the thickness H2 of the first protective adhesive film, the thickness H3 of the third protective adhesive film, the thickness H4 of the fourth protective adhesive film, the thickness H5 of the first active material layer, and the thickness H6 of the first tab satisfy the relationship: H1 = (H6 + H2 + H3 + H4) - H5 ± (5 µm - 10 µm); when the depth H1 of the first receiving opening is smaller than the one-sided thickness H7 of the second active material layer, the distance between the bottom of the first receiving opening and the second collector is greater than or equal to 5 µm and less than or equal to 10 µm.

[0029] In some optional embodiments, the depth H1 of the first receiving opening, the depth H8 of the third receiving opening, the depth H9 of the fourth receiving opening, the thickness H2 of the first protective adhesive film, the thickness H3 of the third protective adhesive film, the thickness H4 of the fourth protective adhesive film, the thickness H5 of the first active material layer, and the thickness H6 of the first tab satisfy the relationship: H1 + H8 = (H6 + H2 + H3 + H4 + H9) - H5 ± (5 µm - 10 µm); when the depth H1 of the first receiving opening or the depth H8 of the third receiving opening is smaller than the one-sided thickness H7 of the second active material layer, the distance between the bottom of the first receiving opening or the third receiving opening and the second collector is greater than or equal to 5 µm and less than or equal to 10 µm to avoid exposing the foil material of the second electrode.

[0030] In some optional embodiments, the relationship between the depth H10 of the second receiving opening and the height K of the weld spot bulge of the first lug satisfies: H10 = 2K ± (5 µm - 10 µm); or the depth H10 of the second receiving opening, the depth H9 of the fourth receiving opening, and the height K of the weld spot bulge of the first lug satisfy: H10 + H9 = 2K ± (5 µm - 10 µm).

[0031] The present invention also includes a battery having the wound cell structure described above.

[0032] The wound cell structure and battery provided in the present invention comprise a wound cell structure; and the wound cell structure comprises a wound first electrode sheet, a separator, and a second electrode sheet. The separator is arranged between the first electrode sheet and the second electrode sheet, which have opposite polarity. The second electrode sheet is provided with a second collector, a second active material layer formed on at least one surface of the second collector, and a second tab. The first electrode sheet is provided with a first collector, a first active material layer formed on at least one surface of the first collector, and a first tab. A welding groove for the first tab is provided in the first active material layer, and the first tab is welded to the first collector in the welding groove.A first receiving opening is formed on the second active material layer, opposite the weld groove. A plurality of grooves are provided at the bottom of the first receiving opening, the openings of which are aligned with the first receiving opening. The grooves run along the longitudinal direction of the first receiving opening.

[0033] The first receiving opening allows the thickness of the tab and other components to be concealed in the active material layer of the electrode sheet, thereby reducing the unusable thickness of the electrode sheet and thus the wound cell. This leads to an increase in the energy density of the lithium-ion battery, improved space utilization, and increased runtime of electronic devices. Furthermore, the multiple grooves increase the friction between the second protective adhesive film and the bottom of the first receiving opening, thereby preventing the second protective adhesive film from slipping and falling off and associated safety risks. At the same time, the grooves in the first receiving opening are spatially connected to the grooves on the surface of the second electrode sheet.As a result, a portion of the electrolyte can flow through the grooves in the first receiving opening into the grooves on the surface of the second electrode sheet, which improves the wetting ability of the electrode sheet formed with a first receiving opening with electrolyte. Short description of the characters

[0034] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, a brief introduction to the drawings used in the description of the embodiments or the prior art is provided below. Obviously, the drawings described below refer to some embodiments of the present invention. Those skilled in the art can obtain further drawings based on these drawings without creative activity. Fig. Figure 1 is a schematic representation of the wound cell structure according to the prior art. Fig. 2 is a schematic representation of a wound cell structure according to an embodiment of the present invention. Fig. 3 is an enlarged detail view of area I in Fig. 2. Fig. 4 is a schematic representation of another wound cell structure according to an embodiment of the present invention. Fig. 5 is a cross section of the wound cell structure along the line AA' in Fig. 2. Fig. 6 is a cross section of the wound cell structure along the line BB' in Fig. 2. Fig. 7 is a cross section of the wound cell structure along the line CC' in Fig. 2. Fig. 8 is a cross section of the wound cell structure along the line DD' in Fig. 2. Fig. 9 is a cross section of the second electrode sheet on the other side. Fig. 10 is another cross section of the second electrode sheet on the other side. List of reference symbols 100 winding cell structure; 110 first electrode sheet; 111 first collector; 112 first active material layer; 113 first flag; 120 second electrode sheet; 121 second collector; 122 second active material layer; 1221 first receiving opening; 1222 second receiving opening; 1223 third receiving opening; 1224 fourth receiving opening; 123 second flag; 130 weld groove; 140 first protective adhesive film; 150 second protective adhesive film; 160 third protective adhesive film; 170 fourth protective adhesive film; 180 groove Detailed description

[0035] In order to more clearly illustrate the objects, technical solutions, and advantages of the embodiments of the present invention, the technical solutions of the embodiments will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments represent only a part of the embodiments of the present invention and not all embodiments. Based on the embodiments disclosed in the present invention, all other embodiments that can be obtained by those skilled in the art without creative effort are included in the scope of the present invention. Unless there is a contradiction, the embodiments described below and their features can be combined with each other.

[0036] In describing the present invention, it should be understood that terms such as "center," "longitudinal direction," "transverse direction," "length," "width," "thickness," "top," "bottom," "front," "rear," "left," "right," "vertical," "horizontal," "upper," "bottom," "inside," "outside," "clockwise," "counterclockwise," "axial," "radial," "circumferential," etc., describe the positional relationships based on the positional relationships shown in the drawings. These terms are used merely to describe the present invention and simplify the illustration, but do not imply that the described devices or elements must necessarily have a particular position or be constructed and operated in a particular manner. Therefore, these terms should not be construed as limitations of the present invention.

[0037] In the present invention, terms such as "assemble," "connect," "couple," "fix," etc., unless expressly stated otherwise, should be interpreted broadly. For example, they may include a fixed connection, a detachable connection, or an integral connection; they may mean a direct connection or an indirect connection through an intermediate element; they may represent a connection between the interiors of two elements or an interaction between two elements. Those skilled in the art may interpret these terms in the present invention according to the specific circumstances.

[0038] It should be noted that in the description of the present invention, terms such as "first," "second," "third," etc., are used merely to distinguish between different chambers and do not imply the order, relative importance, or number of the technical features mentioned. Features marked "first," "second," or "third" may explicitly or implicitly include at least one of these features.

[0039] Fig. Figure 1 shows a schematic representation of the wound cell structure according to the prior art. As in Fig. As shown in Figure 1, to improve the fast-charging capability of a battery, the central structure of the first tab 113 and the second tab 123 is widely used in lithium-ion batteries. The first tab 113 is welded centrally on the first electrode sheet 110, and the second tab 123 is welded centrally on the second electrode sheet 120, effectively reducing the internal resistance of the battery to achieve the fast-charging capability. However, in current solutions, a protective adhesive film is required at the tab welding point to prevent safety issues caused by the membrane penetrating the tab welding point. However, this results in an increase in the unusable thickness of the battery at the tab positions due to the protrusions of the tabs and the protective adhesive film.

[0040] To overcome the above-mentioned deficiencies of the prior art, the present invention provides a wound cell structure and a battery in which the first receiving opening is configured such that the thickness of the tab is concealed in the active material layer of the electrode sheet. This reduces the unusable thickness of the electrode sheet, which in turn reduces the unusable thickness of the wound cell, increases the energy density of the lithium-ion battery, improves space utilization, and extends the operating time of electronic devices. Furthermore, the design of a plurality of grooves increases the friction between the second protective adhesive film and the bottom of the first receiving opening, thereby avoiding safety risks due to the slipping or peeling of the second protective adhesive film.Since the grooves within the first receiving opening and the grooves on the surface of the second electrode sheet are spatially connected, a part of the electrolyte can flow through the grooves of the first receiving opening into the grooves on the surface of the second electrode sheet, thereby improving the wetting rate of the electrode sheet formed with a first receiving opening with electrolyte.

[0041] In the following, the present invention will be described in detail with reference to the accompanying drawings in order to enable those skilled in the art to have a clearer and more detailed understanding of the invention.

[0042] Fig. 2 shows a schematic representation of a wound cell structure according to an embodiment of the present invention, and Fig. 3 is an enlarged detail view of area I in Fig. 2.

[0043] As in Fig. 2 and Fig. As shown in Figure 3, the wound cell structure 100 provided in one embodiment of the present invention includes a wound first electrode sheet 110, a membrane, and a second electrode sheet 120. The membrane is disposed between the first electrode sheet 110 and the adjacent second electrode sheet 120, wherein the first electrode sheet 110 and the second electrode sheet 120 have opposite polarities.

[0044] As in Fig. 7, the second electrode sheet 120 comprises a second collector 121, a second active material layer 122 formed on at least one surface of the second collector 121, and a second tab 123 arranged at a predetermined position of the second active material layer 122. As shown in Fig. 2 and Fig. 5, the first electrode sheet 110 comprises a first collector 111, a first active material layer 112 formed on at least one surface of the first collector 111, and a first tab 113; as shown in Fig. 2, the first active material layer 112 has a weld groove 130 in which the first lug 113 is welded. The second active material layer 122 is provided with a first receiving opening 1221, which is opposite the weld groove 130 of the first lug 113. As shown in Fig. As shown in Figure 3, the bottom of the first receiving opening 1221 has a plurality of grooves 180 whose openings are directed toward the first receiving opening 1221. The grooves 180 extend along the longitudinal direction of the first receiving opening 1221.

[0045] It is understood that a portion of the structure of the first tab 113 may be arranged in the first receiving opening 1221 in the direction of its thickness, thereby compensating for a portion of the thickness of the first tab 113. This reduces the stack thickness at the position of the first tab 113. This further improves the flatness of the wound cell, and the thickness of the wound cell can be reduced to a certain extent, improving the space utilization and energy density of the battery.

[0046] With the above-described arrangement, the first receiving opening 1221 allows the thickness of the tab to be concealed within the active material layer of the electrode sheet, thereby reducing the unusable thickness of the electrode sheet. This leads to a reduction in the unusable thickness of the wound cell, which increases the energy density of the lithium-ion battery, improves space utilization, and extends the operating time of electronic devices. Furthermore, the plurality of grooves 180 increases the friction between the second protective adhesive film 150 and the bottom of the first receiving opening 1221, thereby preventing the risk of a safety problem caused by the slipping and peeling of the second protective adhesive film 150.Since the grooves 180 in the first receiving opening 1221 are spatially connected to the grooves 180 on the surface of the second electrode sheet 120, a portion of the electrolyte can flow through the grooves 180 in the first receiving opening 1221 into the grooves 180 on the surface of the second electrode sheet 120 to improve the efficiency of electrolyte wetting of the electrode sheet with the first receiving opening 1221.

[0047] It should be noted that the first electrode sheet 110 can be used as an anodic electrode sheet, wherein the first collector 111 is the anodic collector, the first active material layer 112 is the anodic active material layer, and the first tab 113 is the anodic tab.

[0048] The second electrode sheet 120 can be used as a cathodic electrode sheet, wherein the second collector 121 is the cathodic collector, the second active material layer 122 is the cathodic active material layer, and the second tab 123 is the cathodic tab.

[0049] It should be noted that the second collector 121 is a high-strength copper foil collector material whose tensile strength is between 300 MPa and 700 MPa, the elongation is between 2.0% and 11%, and the basis weight is between 30 g / m 2 and 65 g / m 2 The use of such a second collector 121 serves to prevent breakage of the second collector 121 due to voltage differences during the welding process. Furthermore, welding burrs are reduced, thereby lowering the risk of puncture. Furthermore, the tensile strength at the weld points is increased, which lowers the contact resistance and thus reduces the internal resistance of the wound cell.

[0050] In some embodiments, the longitudinal direction of the groove 180 may coincide with the width direction of the first receiving opening 1221, coincide with the longitudinal direction of the first receiving opening 1221, or extend in any direction as long as the friction between the second protective adhesive film 150 and the bottom of the first receiving opening 1221 is increased to avoid the safety risk of slipping of the second protective adhesive film 150.

[0051] In other embodiments, the cross-section of the groove 180 is rectangular, conical, or round. The specific shape can be adapted according to the actual circumstances and is not further limited here.

[0052] In some optional embodiments, the depth of the groove 180 is greater than or equal to 3 µm and less than or equal to 15 µm; and / or the width of the groove 180 is greater than or equal to 20 µm and less than or equal to 150 µm; and / or the distance between two adjacent grooves 180 is greater than or equal to 0.5 mm and less than or equal to 2 mm.

[0053] It should be noted that the depth of the groove 180 can be 3 µm, 4 µm, 5 µm, 6 µm, 7 µm, 8 µm, 9 µm, 10 µm, 11 µm, 12 µm, 13 µm, 14 µm or 15 µm or any value in between.

[0054] It should be noted that the width of the groove 180 can be 20 µm, 30 µm, 40 µm, 50 µm, 60 µm, 70 µm, 80 µm, 90 µm, 100 µm, 110 µm, 120 µm, 130 µm, 140 µm or 150 µm or any value in between.

[0055] It should be noted that the distance between two adjacent grooves 180 can be 0.5 mm, 1 mm, 1.5 mm or 2 mm or any value in between.

[0056] Fig. Figure 4 shows a schematic representation of another wound cell structure according to the embodiments of this invention. In some optional embodiments, as in Fig. 2, the upper edge of the first receiving opening 1221 is flush with the upper edge of the second active material layer 122; or as shown in Fig. 4, there is a distance between the upper edge of the first receiving opening 1221 and the upper edge of the second active material layer 122, the distance being greater than or equal to 0.5 mm and less than or equal to 2 mm.

[0057] It should be noted that the upper edge of the first receiving opening 1221 is flush with the upper edge of the second active material layer 122, which can further reduce the unusable thickness of the winding cell.

[0058] It should also be noted that a gap is formed between the upper edge of the first receiving opening 1221 and the upper edge of the second active material layer 122, which means that the upper edge of the first receiving opening 1221 is not flush with the upper edge of the second active material layer 122. This is because a recess is formed at the weld groove 130 of the first tab 113, whereby no thickness overlaps at this point. Therefore, it is not necessary for the upper edge of the first receiving opening 1221 to be flush with the upper edge of the second active material layer 122. When the upper edge of the first receiving opening 1221 is not flush with the upper edge of the second active material layer 122, the gap between the upper edge of the first receiving opening 1221 and the upper edge of the second active material layer 122 is 0.5 mm to 2 mm.This has the advantage of reducing the risk of cracking of the second active material layer 122 at the edge of the first receiving opening 1221.

[0059] In some embodiments, the distance between the upper edge of the first receiving opening 1221 and the upper edge of the second active material layer 122 may be 0.5 mm, 1 mm, 1.5 mm, or 2 mm, or any value therebetween.

[0060] As in Fig. 2 to Fig. 4, in some optional embodiments, the relationship between the width A of the first receiving opening 1221 and the width B of the first tab 113 satisfies the condition B+3 mm < A < B+6 mm; and / or the relationship between the length D of the first receiving opening 1221 and the length E of the welding end of the first tab 113 satisfies the condition E+2 mm < D < E+5 mm.

[0061] It should be noted that this arrangement improves production efficiency and prevents the first tab 113 from being inserted into the first receiving opening 1221 due to production fluctuations, thereby overlapping with the edge of the first receiving opening 1221 and resulting in thickness stacking, which ultimately increases the thickness of the wound cell and reduces the energy density of the lithium-ion battery.

[0062] As in Fig. 2 to Fig. 4, in some optional embodiments, a second protective adhesive film 150 is provided in the first receiving opening 1221. The relationship between the width C of the second protective adhesive film 150 and the width A of the first receiving opening 1221 satisfies the condition A-4 mm < C < A-1 mm, wherein along the width direction of the second protective adhesive film 150, the distance between the edges of the second protective adhesive film 150 and the edges of the first receiving opening 1221 is greater than 0.5 mm; and / or the relationship between the length F of the second protective adhesive film 150 and the length D of the first receiving opening 1221 satisfies the condition D-4 mm < F < D+2 mm, wherein the distance between the lower edge of the second protective adhesive film 150 and the lower edge of the first receiving opening 1221 is greater than 0.5 mm.

[0063] It should be noted that the second protective adhesive film 150 is provided in the first receiving opening 1221 to prevent the coarse bottom surface of the large-area first receiving opening 1221 from rubbing with the separator and generating protruding particles that could pierce the separator and cause a short circuit between the cathodic and anodic electrode sheets.

[0064] Furthermore, it should be noted that this adjustment has the benefit of improving production efficiency and preventing the second protective adhesive film 150 from being inserted into the first receiving opening 1221 due to production fluctuations. This could cause it to overlap with the edges of the first receiving opening 1221, resulting in additional thickness and ultimately increasing the thickness of the wound cell, thereby reducing the energy density of the lithium-ion battery.

[0065] It should be noted that when the upper edge of the first receiving opening 1221 is flush with the upper edge of the second active material layer 122, the upper edge of the second protective adhesive film 150 protrudes 0.5 mm to 2 mm beyond the upper edge of the first receiving opening 1221. This is primarily to prevent burrs at the upper edge from piercing the separator film and thereby causing a short circuit, as well as to reduce the risk of the electrode sheet being torn off. When the upper edge of the first receiving opening 1221 is not flush with the upper edge of the second active material layer 122, the distance between the upper edge of the second protective adhesive film 150 and the upper edge of the first receiving opening 1221 is at least 0.5 mm. The positive effects are the same as described above and will not be further elaborated here.

[0066] As in Fig. 2 to Fig. As shown in Figure 4, in some optional embodiments, a second receiving opening 1222 is formed in the second active material layer 122, which is connected to the first receiving opening 1221. The second receiving opening 1222 is arranged in a direction away from the second active material layer 122, i.e., the opening of the second receiving opening 1222 points away from the second active material layer 122. The second protective adhesive film 150 is used to cover the second receiving opening 1222.

[0067] It should be noted that the second receiving opening 1222 is designed such that the first tab 113 can be at least partially inserted into the second receiving opening 1222. This can reduce the thickness of the wound cell to some extent, thereby improving the space utilization and energy density of the battery.

[0068] In addition, it should be noted that the second protective adhesive film 150 can prevent burrs at the welding points of the first tab 113 from piercing the separator and thus causing the risk of short circuit or fire.

[0069] As in Fig. 2 to Fig. 4, in some optional embodiments, the relationship between the width G of the second receiving opening 1222 and the width B of the first tab 113 satisfies the following conditions: B + 0 mm < G < B + 2 mm, wherein the projection of the first tab 113 in the width direction of the first tab 113 lies within the second receiving opening 1222; and / or the relationship between the length H of the second receiving opening 1222 and the total length P of the weld points of the first tab 113 satisfies: P + 1 mm < H < P + 4 mm, wherein the projection of the weld points of the first tab 113 in the longitudinal direction of the weld points of the first tab 113 lies within the second receiving opening 1222.

[0070] It should be noted that adjusting the width G of the second receiving opening 1222 with respect to the width B of the first tab 113 has the advantage of increasing production efficiency and preventing the first tab 113 from being unable to be inserted into the second receiving opening 1222 in the width direction of the first tab 113, which could result in overlap with the edges of the second receiving opening 1222, which in turn increases the thickness and reduces the energy density of the lithium-ion battery.

[0071] It should be noted that adjusting the length H of the second receiving opening 1222 with respect to the total length P of the welding points of the first lug 113 results in the projection of the welding points of the first lug 113 in the longitudinal direction of the welding points of the first lug 113 being within the second receiving opening 1222 after the formation of a wound lithium-ion battery. The advantageous effect is the same as described above and will not be further explained here.

[0072] In some optional embodiments, the length E of the welding end of the first flag 113 is greater than or equal to 5 mm and less than or equal to 35 mm; and / or the width B of the first flag 113 is greater than or equal to 4 mm and less than or equal to 15 mm; and / or the width of the welding spots of the first flag 113 is less than the width B of the first flag 113, wherein the difference Z between the width of the welding spots of the first flag 113 and the width B of the first flag 113 is as follows: 0.5 mm ≤ Z ≤ 2 mm; and / or along the width of the welding spots of the first flag 113, the distance between the welding spots and the edge of the first flag 113 is more than 0.5 mm.

[0073] It should be noted that the welding points of the first tab 113 are arranged centrally in the width direction or the welding points of the first tab 113 are spaced more than 0.5 mm apart from the edge of the first tab 113 along the width. This arrangement serves to prevent the welding points of the first tab 113 from encroaching on the first collector 111 during welding and damaging it, which would lead to poor welds and an increase in the internal resistance of the cell.

[0074] Furthermore, it should be noted that the total length P of the welding points of the first lug 113 is 2 mm to 8 mm shorter than the final welding length E of the first lug 113, and the welding points are arranged centrally in the longitudinal direction. The purpose of this arrangement is the same as described above. However, the minimum total length P of the welding points of the first lug 113 is at least 3 mm. This arrangement ensures that the first lug 113 and the first collector 111 have a sufficient welding area to avoid poor contact quality due to an insufficient contact area, as well as an increase in contact resistance, which would ultimately lead to an increase in the internal resistance of the wound cell.

[0075] In some embodiments, the final weld length E of the first tab 113 may be 5 mm, 10 µm, 15 µm, 20 µm, 25 µm, 30 µm, or 35 µm, or any value therebetween.

[0076] In some embodiments, the width B of the first tab 113 may be 4 mm, 5 µm, 6 µm, 7 µm, 8 µm, 9 µm, 10 µm, 11 µm, 12 µm, 13 µm, 14 µm or 15 µm, or any value therebetween.

[0077] In some embodiments, the width of the weld spots of the first tab 113 is 0.5 mm, 1 mm, 1.5 mm, or 2 mm smaller than the width B of the first tab 113, or any value therebetween.

[0078] Fig. Figure 5 shows a cross section along the line AA' in Fig. 2 of the winding cell structure. Fig. 6 shows a cross section along the line BB' in Fig. 2 of the winding cell structure. As in Fig. 2 to Fig. As shown in Figure 6, in some optional embodiments, a first protective adhesive film 140 is arranged on the weld groove 130 of the first tab 113, which is located on the side of the first electrode sheet 110. The first protective adhesive film 140 serves to cover the first receiving opening 1221.

[0079] It should be noted that the surface of the first protective adhesive film 140 covers the surface of the welding groove 130 of the first tab 113, with the projection surface of its coverage on the second electrode sheet 120 being within the first receiving opening 1221.

[0080] In some optional embodiments, the distance between the edge of the first protective adhesive film 140 and the edge of the first receiving opening 1221 is more than 1 mm and less than 5 mm.

[0081] It should be noted that if the area of ​​the first protective adhesive film 140 covers the area of ​​the weld groove 130 of the first tab 113, the distance between the edge of the first protective adhesive film 140 and the edge of the first receiving opening 1221 is at least 1 mm. This setting is to avoid the problem of lithium precipitation caused by a reduction in the amount of active material within the first receiving opening 1221, which prevents lithium ions from being absorbed by the corresponding anode. Therefore, the anode arranged on the opposite side of the first receiving opening 1221 is covered with the first protective adhesive film 140 to avoid the problem of lithium precipitation at the cathode caused by the release of the corresponding lithium ions. The distance between the edge of the first protective adhesive film 140 and the edge of the first receiving opening 1221 is a maximum of 5 mm.This setting is intended to avoid covering too much anode material, which leads to a loss of capacity and ultimately a reduction in energy density.

[0082] As in the Fig. 2 to Fig. As shown in Figure 6, in some optional embodiments, the weld groove 130 of the first tab 113 is formed on both sides. A third protective adhesive film 160 is arranged on the weld groove 130, which is arranged on the opposite side of the first electrode sheet 110. The third protective adhesive film 160 and the first protective adhesive film 140 are each arranged on the opposite sides of the first electrode sheet 110; and the total height of the weld points of the first tab 113 (for example, the height K of the protruding weld points) is greater than or equal to 10 µm and less than or equal to 65 µm.

[0083] As from Fig. As can be seen from Figure 5, the line AA' is arranged at a position without welding spots. The welding groove 130 of the first tab 113 is formed on both sides. The first tab 113 is welded in the welding groove 130. The thickness of the first tab 113 exceeds the thickness of the first electrode sheet 110, and the welding groove 130 is covered on both sides with the first protective adhesive film 140 and the third protective adhesive film 160. The welding groove 130 of the first tab 113 can also be formed on one side, i.e., the welding groove 130 of the first tab 113 is arranged only on one side of the first tab 113 facing the welding.

[0084] As from Fig. As can be seen from Figure 6, the line BB' is arranged at a position with weld spots. The weld groove 130 of the first tab 113 is formed on both sides. The first tab 113 is welded in the weld groove 130. The thickness of the first tab 113 exceeds the thickness of the first electrode sheet 110, and the weld groove 130 is covered on both sides with the first protective adhesive film 140 and the third protective adhesive film 160. At the same time, the total height of the weld spots of the first tab 113 ranges from 10 µm to 65 µm (relative to the plane of the first tab 113, measured as the height extending beyond this plane). The weld spots of the first tab 113 are distributed on both sides.Alternatively, the welding groove 130 of the first lug 113 may be single-sided and arranged only on one side of the first lug 113 facing the welding; At the same time, the total height of the welding spots of the first lug 113 is between 10 µm and 65 µm, and the welding spots are arranged only on the outer side of the first lug 113.

[0085] Fig. Figure 7 shows a cross section along the line CC' in Fig. 2. As in Fig. As shown in Figure 7, the CC' line is located at a position without any welding points on the first electrode sheet 110. At this position, there is no second receiving opening 1222, but rather a second protective adhesive film 150 is applied.

[0086] Fig. Figure 8 shows a cross section along the line DD' in Fig. 2. As in Fig. As shown in Figure 8, the line DD' is located at a position with welding points of the first electrode sheet 110. At this position, a second receiving opening 1222 is provided, which is covered with a second protective adhesive film 150. The second protective adhesive film 150 is attached to the second receiving opening 1222 and has a concave shape.

[0087] Fig. 9 and Fig. 10 show cross sections on the other side of the second electrode sheet.

[0088] As in the Fig. 2 to Fig. 10, in some optional embodiments, a first receiving opening 1221 is arranged on the second active material layer 122 of one side of the second electrode sheet 120 and a third receiving opening 1223 is arranged on the second active material layer 122 of the opposite side of the second electrode sheet 120.

[0089] It is understood that part of the structure of the first tab 113 can be accommodated in the third receiving opening 1223, which can compensate for part of the thickness of the first tab 113, thereby reducing the stack thickness of the first tab 113. This improves the flatness of the wound cell and reduces its thickness, optimizing the space utilization and energy density of the battery.

[0090] As in the Fig. 2 to Fig. As shown in Figure 10, a fourth protective adhesive film 170 is applied to the third receiving opening 1223; and a fourth receiving opening 1224 is provided on the second active material layer 122 of the opposite side of the second electrode sheet 120, which is connected to the third receiving opening 1223. The fourth receiving opening 1224 is formed in a direction away from the second active material layer 122. That is, the opening of the fourth receiving opening 1224 faces away from the second active material layer 122, and the fourth protective adhesive film 170 is used to cover the fourth receiving opening 1224.

[0091] It should be noted that the fourth protective adhesive film 170 is applied in the third receiving opening 1223 to prevent particles from protruding through the coarse bottom of the large-area third receiving opening 1223, which could pierce the separator and lead to a short circuit between the anode and the cathode.

[0092] It should be noted that the provision of the fourth receiving opening 1224 allows the first tab 113 to be at least partially embedded in the fourth receiving opening 1224. This allows the wound cell thickness to be reduced to a certain extent, which in turn improves the space utilization efficiency and energy density of the battery.

[0093] As in the Fig. 2 to Fig. 10, in some optional embodiments, the relationship between the depth H1 of the first receiving opening 1221, the thickness H2 of the first protective adhesive film 140, the thickness H3 of the third protective adhesive film 160, the thickness H4 of the fourth protective adhesive film 170, the thickness H5 of the first active material layer 112, and the thickness H6 of the first tab 113 is defined as follows: H1 = (H6 + H2 + H3 + H4) - H5 ± (5 µm - 10 µm); when the depth H1 of the first receiving opening 1221 is smaller than the single-layer thickness H7 of the second active material layer 122, the distance between the bottom of the first receiving opening 1221 and the second collector 121 is greater than or equal to 5 µm and less than or equal to 10 µm.

[0094] It should be noted that when the depth H1 of the first receiving opening 1221 is less than or equal to the single-layer thickness H7 of the second active material layer 122, the principle of complete coverage of the cathodic collector should be observed; the bottom of the first receiving opening 1221 has a layer of 5 µm to 10 µm up to the second collector 121 to avoid exposing the cathodic foil.

[0095] As in the Fig. 2 to Fig. 10, in some optional embodiments, the depth H1 of the first receiving opening 1221, the depth H8 of the third receiving opening 1223, the depth H9 of the fourth receiving opening 1224, the thickness H2 of the first protective adhesive film 140, the thickness H3 of the third protective adhesive film 160, the thickness H4 of the fourth protective adhesive film 170, the thickness H5 of the first active material layer 112, and the thickness H6 of the first tab 113 satisfy the following relationship: H1 + H8 = (H6 + H2 + H3 + H4 + H9) - H5 ± (5 µm - 10 µm); when the depth H1 of the first accommodating opening 1221 or the depth H8 of the third accommodating opening 1223 is smaller than the single-layer thickness H7 of the second active material layer 122, the distance between the bottom of the first accommodating opening 1221 or third accommodating opening 1223 and the second collector 121 is greater than or equal to 5 µm and less than or equal to 10 µm.

[0096] It should be noted that the depth H1 of the first receiving opening 1221 and the depth H8 of the third receiving opening 1223 may be the same or different, but are preferably the same.

[0097] At the same time, when the depth H1 of the first receiving opening 1221 or the depth H8 of the third receiving opening 1223 is less than or equal to the single-layer thickness H7 of the second active material layer 122, the principle of completely covering the cathodic collector should be observed; the bottom of the first receiving opening 1221 or third receiving opening 1223 has a layer of 5 µm to 10 µm up to the second collector 121 to avoid exposing the cathodic foil.

[0098] As in the Fig. 2 to Fig. 10, in some optional embodiments, the relationship between the depth H10 of the second receiving opening 1222 in the second active material layer 122 and the height K of the protruding weld points of the first tab 113 is defined as follows: H10 = 2K ± (5 µm - 10 µm); or the depth H10 of the second receiving opening 1222, the depth H9 of the fourth receiving opening 1224, and the height K of the protruding weld points of the first tab 113 satisfy the following relationship: H10 + H9 = 2K ± (5 µm - 10 µm).

[0099] It should be noted that when the second receiving opening 1222 is provided only on one side of the second electrode sheet 120 corresponding to the welding location of the first tab 113, the depth H10 of the second receiving opening 1222 and the height K of the protruding welding points of the first tab 113 satisfy the following relationship: H10 = 2K ± (5 µm - 10 µm). The bottom of the second receiving opening 1222 can also directly form the surface of the second collector 121 to reduce manufacturing complexity.

[0100] Alternatively, if a second receiving opening 1222 and a fourth receiving opening 1224 are provided on both sides of the second electrode sheet 120 corresponding to the welding point of the first tab 113, the depth H10 of the second receiving opening 1222, the depth H9 of the fourth receiving opening 1224, and the height K of the protruding weld points of the first tab 113 satisfy the following relationship: H10 + H9 = 2K ± (5 µm - 10 µm). The depth H10 of the second receiving opening 1222 and the depth H9 of the fourth receiving opening 1224 may be equal or unequal, but are preferably equal. In addition, the bottoms of both openings may extend directly to the second collector 121 to reduce manufacturing complexity.

[0101] It should be understood that the longitudinal direction in the present invention means the vertical direction according to Fig. 2 (ie the up and down direction); accordingly, the length refers to the dimension along the Fig. 2. The transverse direction refers to the horizontal direction according to Fig. 2 (i.e. the left and right directions); accordingly, the width refers to the dimension along the Fig. 2. The thickness refers to the vertical direction according to Fig. 5 to Fig. 10 (ie the up and down direction); accordingly, height or depth refers to the dimension along the Fig. 5 to Fig. 10 shown vertical direction.

[0102] The wound cell structure provided in one embodiment of this invention comprises a wound first electrode sheet, a separator, and a second electrode sheet, wherein the separator is arranged between the first and second electrode sheets. The second electrode sheet has a second collector, a second active material layer formed on at least one surface of the second collector, and a second tab. The first electrode sheet has a first collector, a first active material layer formed on at least one surface of the first collector, and a first tab. A welding groove for the first tab is provided on the first active material layer, wherein the first tab is welded to the first collector in the welding groove. A first receiving opening is provided on the second active material layer, which is opposite the welding groove of the first tab.At the bottom of the first receiving opening, several grooves are arranged, the openings of which point toward the first receiving opening. The grooves extend along the longitudinal direction of the first receiving opening.

[0103] The design of the first receiving opening allows the thickness of the tab to be embedded into the active material layer of the electrode sheet, reducing the unusable thickness of the electrode sheet. This reduces the unusable thickness of the wound cell, increasing the energy density of the lithium-ion battery, improving space utilization, and extending the battery life of electronic devices. Furthermore, the arrangement of multiple grooves increases the friction between the second protective adhesive film and the bottom of the first receiving opening, reducing the risk of a safety issue caused by the second protective adhesive film slipping off.Since the grooves in the first receiving opening and the grooves on the surface of the second electrode sheet are spatially connected, a part of the electrolyte can flow through the grooves in the first receiving opening into the grooves on the surface of the second electrode sheet, thereby improving the wetting effect of the electrode sheet equipped with the first receiving opening.

[0104] Furthermore, in one embodiment of this invention, a battery having the wound cell structure 100 is also provided.

[0105] The specific structure, the working principle and the mode of operation of the winding cell structure 100 have already been described in detail in the previous embodiments and are therefore not repeated here.

[0106] The battery provided in one embodiment of this invention utilizes the provision of the first receiving opening to embed the thickness of the tab into the active material layer of the electrode sheet. This reduces the unusable thickness of the electrode sheet and the wound cell, thereby increasing the energy density of the lithium-ion battery, improving space utilization, and extending the battery life of electronic devices. Furthermore, the arrangement of multiple grooves increases the friction between the second protective adhesive film and the bottom of the first receiving opening, thereby reducing the risk of a safety issue caused by the second protective adhesive film slipping off.Since the grooves in the first receiving opening and the grooves on the surface of the second electrode sheet are spatially connected, a part of the electrolyte can flow through the grooves in the first receiving opening into the grooves on the surface of the second electrode sheet, thereby improving the wetting effect of the electrode sheet equipped with the first receiving opening.

[0107] Finally, it should be noted that the above embodiments serve only to illustrate the technical solution of the present utility model and do not constitute a limitation. Although the technical solutions of the present utility model have been described in detail using the above embodiments, a person skilled in the art should understand that modifications or equivalent replacements can be made to the technical solutions described in the above embodiments without departing from the essential content of the technical solutions of the present invention.

Claims

[1] Winding cell structure (100), characterized by a wound first electrode sheet (110), a separator and a second electrode sheet (120), wherein the separator is arranged between the adjacent first electrode sheet (110) and the second electrode sheet (120), and wherein the first electrode sheet (110) and the second electrode sheet (120) have opposite polarities; the second electrode sheet (120) is provided with a second collector (121), a second active material layer (122) formed on at least one surface of the second collector (121), and a second tab (123), while the first electrode sheet (110) is provided with a first collector (111), a first active material layer (112) formed on at least one surface of the first collector (111), and a first tab (113); a welding groove (130) for the first lug (113) is provided on the first active material layer (112), the first lug (113) being welded to the first collector (111) within the welding groove (130); a first receiving opening (1221) is formed on the second active material layer (122), which is opposite to the welding groove (130); and the bottom of the first receiving opening (1221) has a plurality of grooves (180) extending along the longitudinal direction of the first receiving opening (1221). [2] Winding cell structure (100) according to claim 1, characterized by that the depth of the grooves (180) is greater than or equal to 3 µm and less than or equal to 15 µm; and / or the width of the grooves (180) is greater than or equal to 20 µm and less than or equal to 150 µm; and / or the distance between two adjacent grooves (180) is greater than or equal to 0.5 mm and less than or equal to 2 mm. [3] Winding cell structure (100) according to claim 1, characterized bythat the upper edge of the first receiving opening (1221) is aligned with the upper edge of the second active material layer (122); or a gap is formed between the upper edge of the first receiving opening (1221) and the upper edge of the second active material layer (122), the size of which gap is greater than or equal to 0.5 mm and less than or equal to 2 mm. [4] Winding cell structure (100) according to one of claims 1 to 3, characterized by that the width A of the first receiving opening (1221) and the width B of the first lug (113) are in the following relationship: B + 3 mm < A < B + 6 mm; and / or the length D of the first receiving opening (1221) and the length E of a welding end of the first lug (113) are in the following relationship: E + 2 mm < D < E + 5 mm. [5] Winding cell structure (100) according to one of claims 1 to 3, characterized bythat a second protective adhesive film (150) is arranged within the first receiving opening (1221); the width C of the second protective adhesive film (150) and the width A of the first receiving opening (1221) have the following relationship: A - 4 mm < C < A - 1 mm, and in the direction of the width of the second protective adhesive film (150), the distance between its edge and the edge of the first receiving opening (1221) is greater than 0.5 mm; and / or the length F of the second protective adhesive film (150) and the length D of the first receiving opening (1221) have the following relationship: D - 4 mm < F < D + 2 mm, and the distance between the lower edge of the second protective adhesive film (150) and the lower edge of the first receiving opening (1221) is greater than 0.5 mm. [6] Winding cell structure (100) according to claim 5, characterized bythat a second receiving opening (1222) is formed on the second active material layer (122), which is connected to the first receiving opening (1221); the second receiving opening (1222) extends in a direction away from the second active material layer (122), and the second protective adhesive film (150) serves to cover the second receiving opening (1222). [7] Winding cell structure (100) according to claim 6, characterized bythat the width G of the second receiving opening (1222) and the width B of the first flag (113) are in the following relationship: B + 0 mm < G < B + 2 mm, wherein the projection of the first flag (113) in the width direction of the first flag (113) lies within the second receiving opening (1222); and / or the length H of the second receiving opening (1222) and the total length P of the welding points of the first flag (113) are in the following relationship: P + 1 mm < H < P + 4 mm, wherein the projection of the welding points of the first flag (113) in the longitudinal direction of the welding points of the first flag (113) lies within the second receiving opening (1222). [8] Winding cell structure (100) according to one of claims 1 to 3, characterized by that the length of the welding end of the first lug (113) is greater than or equal to 5 mm and less than or equal to 35 mm; and / or the width of the first flag (113) is greater than or equal to 4 mm and less than or equal to 15 mm; and / or the width of the welding spots of the first lug (113) is smaller than the width of the first lug (113), wherein the difference Z between the width of the welding spots and the width of the first lug (113) satisfies the following relationship: 0.5 mm ≤ Z ≤ 2 mm; and / or in the direction of the width of the welding points of the first flag (113) the distance between the welding points and the edge of the first flag (113) is greater than 0.5 mm. [9] Winding cell structure (100) according to one of claims 1 to 3, characterized by that on the side of the first electrode sheet (110) on which the welding groove (130) is arranged, a first protective adhesive film (140) is applied, which is designed to cover the first receiving opening (1221); the distance between the edge of the first protective adhesive film (140) and the edge of the first receiving opening (1221) is greater than 1 mm and less than 5 mm. [10] Winding cell structure (100) according to claim 9, characterized byin that the welding groove (130) is a double-sided welding groove and a third protective adhesive film (160) is applied to the welding groove (130) of the other side of the first electrode sheet (110), wherein the third protective adhesive film (160) and the first protective adhesive film (140) are each applied to the opposite sides of the first electrode sheet (110); the total height of the welding points of the first lug (113) is greater than or equal to 10 µm and less than or equal to 65 µm. [11] Winding cell structure (100) according to claim 10, characterized by that the first receiving opening (1221) is formed on the side of the second electrode sheet (120) on which the second active material layer (122) is arranged, and a third receiving opening (1223) is formed on the second active material layer (122) of the other side of the second electrode sheet (120); a fourth protective adhesive film (170) is applied in the third receiving opening (1223); on the second active material layer (122) of the other side of the second electrode sheet (120), a fourth receiving opening (1224) is further formed, which is connected to the third receiving opening (1223) and extends in the direction away from the second active material layer (122), wherein the fourth protective adhesive film (170) is designed to cover the fourth receiving opening (1224). [12] Winding cell structure (100) according to claim 11, characterized bythat the depth H1 of the first receiving opening (1221), the thickness H2 of the first protective adhesive film (140), the thickness H3 of the third protective adhesive film (160), the thickness H4 of the fourth protective adhesive film (170), the thickness H5 of the first active material layer (112) and the thickness H6 of the first tab (113) satisfy the following relationship: H1 = (H6 + H2 + H3 + H4) - H5 ± (5 µm - 10 µm); when the depth H1 of the first receiving opening (1221) is smaller than the one-sided thickness H7 of the second active material layer (122), the distance between the bottom of the first receiving opening (1221) and the second collector (121) is greater than or equal to 5 µm and less than or equal to 10 µm. [13] Winding cell structure (100) according to claim 11, characterized bythat the depth H1 of the first receiving opening (1221), the depth H8 of the third receiving opening (1223), the depth H9 of the fourth receiving opening (1224), the thickness H2 of the first protective adhesive film (140), the thickness H3 of the third protective adhesive film (160), the thickness H4 of the fourth protective adhesive film (170), the thickness H5 of the first active material layer (112) and the thickness H6 of the first tab (113) satisfy the following relationship: H1 + H8 = (H6 + H2 + H3 + H4 + H9) - H5 ± (5 µm - 10 µm);if the depth H1 of the first receiving opening (1221) is smaller than the one-sided thickness H7 of the second active material layer (122), the distance between the bottom of the first receiving opening (1221) and the second collector (121) is greater than or equal to 5 µm and less than or equal to 10 µm, and / or if the depth H8 of the third receiving opening (1223) is smaller than the one-sided thickness H7 of the second active material layer (122), the distance between the bottom of the third receiving opening (1223) and the second collector (121) is greater than or equal to 5 µm and less than or equal to 10 µm.; [14] Winding cell structure (100) according to claim 11, characterized bythat the depth H10 of the second receiving opening (1222) and the height K of the elevation of the welding points of the first lug (113) satisfy the following relationship: H10 = 2K ± (5 µm - 10 µm); or the depth H10 of the second receiving opening (1222), the depth H9 of the fourth receiving opening (1224) and the height K of the elevation of the welding points of the first lug (113) satisfy the following relationship: H10 + H9 = 2K ± (5 µm - 10 µm). [15] Battery, characterized by that it has the winding cell structure (100) according to one of claims 1 to 14.

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