Roll core and battery
By adding an extension sheet to the outermost layer of the core and winding it with the separator to form a separator, the problem of outer electrode breakage caused by inner electrode expansion is solved, ensuring normal charge and discharge cycles of the battery.
Patent Information
- Application Number
- CN202422808361.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-18
- Publication Date
- 2025-11-21
- Estimated Expiration
- 2034-11-18
AI Technical Summary
In existing wound-cell batteries, during charging and discharging, the inner electrode plates tend to squeeze the outer electrode plates, causing the outermost electrode plates to break and affecting the normal charging and discharging of the battery.
An extension strip is added to the outermost layer of the core. The extension strip is connected to the first or second electrode and wound together with the separator to form a separator. The end is fixed with adhesive tape. The extension strip is located on the outermost ring and bears the fracture caused by expansion force, so as to avoid affecting the normal charging and discharging of the battery.
By adding an extension sheet to the outermost layer of the core, the direct compression of the outer electrode sheet by the inner electrode sheet during expansion is avoided, reducing breakage and ensuring normal charge and discharge cycles of the battery.
Smart Images
Figure CN223583081U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a battery field especially relates to a winding core and battery. BACKGROUND
[0002] Battery refers to cup, tank or other container or composite container's partial space that contains electrolyte solution and metal electrode to produce electric current, and can convert chemical energy into electric energy. Battery has the division of positive pole and negative pole. The above-mentioned advantages make battery play a very big role in various aspects of modern social life by using battery as energy source, which can obtain the electric current with stable voltage, stable current, long time stable power supply, little influence from outside.
[0003] The existing battery mostly adopts winding core, and the more the winding layers of the winding core, the larger the diameter is. In the charging and discharging process, the pole piece of the inner circle of the winding core is expanded, so that the pole piece of the inner circle extrudes the pole piece of the outer circle, which easily leads to the fracture of the pole piece of the outermost circle, thereby affecting the normal charging and discharging of the battery. SUMMARY
[0004] The utility model discloses a winding core and battery to solve the problem that the pole piece of the inner circle of the existing winding core battery extrudes the pole piece of the outer circle, which easily leads to the fracture of the pole piece of the outermost circle, thereby affecting the normal charging and discharging of the battery.
[0005] On the one hand, the utility model discloses a winding core, which comprises a first pole piece, a second pole piece, a diaphragm, an extension piece and a tailing paper, the diaphragm is arranged between the first pole piece and the second pole piece, the diaphragm is arranged on the side of the first pole piece away from the second pole piece and / or the side of the second pole piece away from the first pole piece, and the first pole piece, the second pole piece and the diaphragm are wound to form a winding core body. One of the first pole piece and the second pole piece is a positive pole piece, and the other is a negative pole piece.
[0006] The first pole piece comprises a first foil piece and a first active layer coated on the first foil piece, and the second pole piece comprises a second foil piece and a second active layer coated on the second foil piece.
[0007] The length of the first pole piece is greater than the length of the second pole piece, the outer end of the first foil piece or the outer end of the second foil piece is connected with the inner end of the extension piece, the extension piece is wound outside the winding core body, and the extension piece is wound at least once.
[0008] The length of the diaphragm is greater than the length of the first pole piece, the part of the diaphragm exceeding the first pole piece is wound together with the extension piece to form a diaphragm piece, and the outer end of the diaphragm piece is wound outside the extension piece.
[0009] The tailing adhesive paper is annular, and the tailing adhesive paper is wound on the outer side of the separator.
[0010] Optionally, the length of the separator is greater than the length of the extension sheet.
[0011] Optionally, the first tab is welded on the first foil sheet, and the second tab is welded on the second foil sheet.
[0012] The first tab is close to the outer end of the first foil sheet, and the second tab is close to the outer end of the second foil sheet.
[0013] Optionally, the first foil sheet is a copper foil sheet, and the second foil sheet is an aluminum foil sheet; and the extension sheet is an aluminum foil sheet.
[0014] The extension sheet and the first foil sheet are integrally formed.
[0015] Optionally, the winding angle of the extension sheet is greater than 360°, the first tab is located on the inner side of the extension sheet, the outer end of the extension sheet exceeds the first tab, and the length of the extension sheet exceeding the first tab is greater than 1 mm.
[0016] Optionally, the first foil sheet is a copper foil sheet, and the second foil sheet is an aluminum foil sheet; and the extension sheet is an aluminum foil sheet, and the extension sheet and the second foil sheet are integrally formed.
[0017] Optionally, the winding angle of the extension sheet is greater than 360°, the second tab is located on the inner side of the extension sheet, the outer end of the extension sheet exceeds the second tab, and the length of the extension sheet exceeding the second tab is greater than 1 mm.
[0018] Optionally, the width of the first tab is greater than the width of the second tab.
[0019] Optionally, the difference between the width of the first tab and the width of the second tab is greater than 0.3 mm.
[0020] Optionally, the width of one of the first tab and the second tab ranges from 3 mm to 40 mm.
[0021] Optionally, the length of one of the first tab and the second tab ranges from 100 mm to 600 mm.
[0022] In another aspect, the utility model further provides a battery comprising the winding core.
[0023] The utility model discloses a winding core and battery, and the embodiment increases a circle of extension piece on the outermost layer of the winding core main body, when the pole piece of the inner circle of the winding core expands, even if the expansion force that the inner circle outwardly exerts is very big, but because the outermost circle is the extension piece, the fracture phenomenon occurs on the extension piece of the outermost circle, not on the first pole piece and the second pole piece of the second outer circle, and the fractured extension piece does not affect the normal charge and discharge cycle of the battery. BRIEF DESCRIPTION OF DRAWINGS
[0024] In order to make the technical problems, technical schemes and beneficial effects solved by the utility model clearer, the following will further describe the utility model with the drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and do not limit the utility model.
[0025] Figure 1 is a winding structure diagram of the winding core in an embodiment of the utility model,
[0026] Figure 2 is an enlarged view of part A of Figure 1
[0027] Figure 3 is a position diagram of the first pole lug and the outer end of the first pole piece of the winding core in an embodiment of the utility model,
[0028] Figure 4 is another winding structure diagram of the winding core in an embodiment of the utility model.
[0029] Figure 5 is an enlarged view of part B of Figure 4
[0030] Reference signs: 1, first pole piece; 11, first foil piece; 12, first active layer; 2, second pole piece; 21, second foil piece; 22, second active layer; 3, diaphragm; 4, extension piece; 5, spacer; 6, end adhesive paper; 7, first pole lug; 8, second pole lug. DETAILED DESCRIPTION
[0031] In order to make the technical problems, technical schemes and beneficial effects solved by the utility model clearer, the following will further describe the utility model with the drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and do not limit the utility model.
[0032] In the description of the utility model, it needs to be understood that, the orientation or position relation indicated by the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is the orientation or position relation based on the drawings shown, and is only for the convenience of describing the utility model and simplifying the description, and therefore cannot be understood as a limitation on the utility model. In the description of the utility model, the meaning of "a plurality of" is two or more than two, unless otherwise specified.
[0033] In the description of the utility model, it needs to be understood that, the orientation or position relation indicated by the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is the orientation or position relation based on the drawings shown, and is only for the convenience of describing the utility model and simplifying the description, and therefore cannot be understood as a limitation on the utility model. In the description of the utility model, the meaning of "a plurality of" is two or more than two, unless otherwise specified.
[0034] Referring to Figure 1 And Figure 2 The utility model discloses a kind of roll core, including extension sheet 4, first pole piece 1, second pole piece 2 and diaphragm 3, the diaphragm 3 is set between the first pole piece 1 and the second pole piece 2;And same as prior art, first pole piece 1, second pole piece 2 and diaphragm 3 form winding main body under the winding of winding machine.The first pole piece 1 includes first foil sheet 11 and first active layer 12 coated on both sides of first foil sheet 11, and the second pole piece 2 includes second foil sheet 21 and second active layer 22 coated on both sides of second foil sheet 21.
[0035] The length of the first pole piece 1 is greater than the length of the second pole piece 2, the outer end of the first foil sheet 11 or the outer end of the second foil sheet 21 is connected with the inner end of the extension sheet 4, the extension sheet 4 is wound outside the roll core main body, and at least one winding is formed on the extension sheet 4 to make the extension sheet 4 wound outside the roll core main body. In the embodiment, the extension sheet 4 is wound around the roll core main body, the inner end of the extension sheet 4 is connected with the first foil sheet 11 or the second foil sheet 21, and the outer end of the extension sheet 4 is wound at least one winding, so that the winding core is completely located in the annular cavity formed by the extension sheet 4. The length of the diaphragm is greater than the length of the first pole piece. The first pole piece is a negative pole piece, and the second pole piece is a positive pole piece.
[0036] The outer end of the diaphragm 3 is wound together with the extension sheet 4 to form a diaphragm sheet 5, the outer end of the diaphragm sheet 5 is wound on the outside of the extension sheet 4, and the outer end of the extension sheet 4 is located on the inside of the diaphragm sheet 5.
[0037] The end paper 6 is annular, and the end paper 6 is wound on the outside of the end paper 6.
[0038] The manufacturing method of the core body in the embodiment is the same as that in the prior art, but different from the prior art is that the first foil 11 or the second foil 21 is connected with the extension sheet 4 before winding, so that the first foil 11 and the extension sheet 4 form an integral whole, or the second foil 21 and the extension sheet 4 form an integral whole, taking the example that the first foil 11 and the extension sheet 4 form an integral whole, the extension sheet 4 is continuously wound after the core body is manufactured, and at the same time, the diaphragm 3 is also continuously wound with the extension sheet 4, the diaphragm 3 wound beyond the core body is called a diaphragm sheet 5, the diaphragm sheet 5 located between the extension sheet 4 and the core body plays a role of insulating the extension sheet 4 and the core body, after the diaphragm sheet 5 and the extension sheet 4 are wound at least 360°, the diaphragm sheet 5 is located on the outer circle of the extension sheet 4, the diaphragm sheet 5 is continuously wound on the circumference of the core body beyond the outer end of the extension sheet 4, and then the end paper 6 is wound on the outer circle of the diaphragm sheet 5 to fix the core body, the diaphragm sheet 5 and the extension sheet 4.
[0039] The embodiment adds one more circle of the extension sheet 4 to the outermost layer of the core body, when the pole sheet of the inner circle of the core expands, even if the expansion force applied outward by the inner circle is large, the fracture phenomenon occurs on the extension sheet 4 of the outermost circle, not on the first pole sheet 1 and the second pole sheet 2 of the second outer circle, and the fractured extension sheet 4 does not affect the normal charge and discharge cycle of the battery.
[0040] As an example, the first tab 7 and the second tab 8 are also included, the first tab 7 is welded on the first foil 11, and the second tab 8 is welded on the second foil 21; the first tab 7 is close to the outer end of the first foil 11, and the second tab 8 is close to the outer end of the second foil 21.
[0041] Different from the prior art that the positive and negative pole tabs are usually arranged at the position close to the winding center of the core, in the embodiment, the first tab 7 can be arranged on the surface of the first foil 11 close to the outer end of the first foil 11, and the second tab 8 can be arranged on the surface of the second foil 21 close to the outer end of the second foil 21, so as to adapt to the battery that needs to arrange the positive and negative pole tabs on the outer circle of the core.
[0042] In the embodiment, the included angle formed by the line connecting the first tab 7 and the center of the core and the line connecting the second tab 8 and the center of the core can be any angle.
[0043] In one embodiment, according to the winding core described above, the first foil 11 in this embodiment is a copper foil, the first tab 1 is a negative electrode, the second foil 21 is an aluminum foil, and the second tab 2 is a positive electrode; the extension piece 4 is a copper foil piece, and the extension piece 4 and the first foil 11 are integrally formed. The region of the outer end of the first foil 11 that is not coated with the first active layer 12 constitutes the extension piece 4. Therefore, in actual production, the length of the empty foil at the outer end of the first tab 1 is extended to form the extension piece 4. During winding, the extension piece 4 is wound at least one additional turn outside the outer circle of the winding core body based on the existing production operation, so that the extension piece 4 completely wraps the winding core body.
[0044] As an example, the winding angle of the extension piece 4 is greater than 360°, and during winding, the outer end of the extension piece 4 protrudes beyond the first tab 7, and the length of the extension piece 4 that protrudes beyond the first tab 7 is greater than 1 mm.
[0045] Reference Figure 1 and Figure 3 For ease of description, in this embodiment, the surface formed by the side surface of the first tab 7 near the outer end of the extension piece 4 and the central axis of the winding core body is referred to as surface L, and the surface formed by the outer end surface of the extension piece 4 and the central axis of the winding core body is referred to as surface D. The length of the extension piece 4 between surface L and surface D must be greater than 1 mm. By this arrangement, the first tab 7 is completely wrapped in the extension piece 4, thereby reducing the stress concentration phenomenon caused by welding between the first tab 1 and the first tab 7, which easily causes the first tab 1 to break at the region near the first tab 7. Since the extension piece 4 exerts a restraining force on the stress concentration region, the breaking phenomenon of the first tab 1 is reduced.
[0046] As an example, one of the width of the first tab 1 and the width of the second tab 2 is 3-40 mm, and the width of the first tab 1 is greater than the width of the second tab 2. As in the prior art, the length of the first tab 1 is greater than the length of the second tab 2, and the width of the first tab 1 also needs to be greater than the width of the second tab 2, so that the first tab 1 achieves overhang, that is, negative overdesign, thereby reducing the occurrence of lithium dendrite precipitation. Therefore, in this embodiment, the inner end and the outer end of the first tab 1 in the length direction both protrude beyond the length direction of the second tab 2, and the two side edges of the width direction of the first tab 1 also protrude beyond the two side edges of the second tab 2.
[0047] More specifically, in the present embodiment, the difference between the width of the first tab 1 and the width of the second tab 2 is greater than 0.3mm. The difference between the width of the first tab 1 and the width of the second tab 2 ranges depending on different battery types, such as 0.3-0.6mm for button cell batteries, 1-2mm for cylindrical batteries.
[0048] As an example, the length of one of the first tab 1 and the second tab 2 is 100-600mm. The width of the first tab 1 or the width of the second tab 2 can be between 3-40mm, and the width of the first tab 1 or the width of the second tab 2 is preferably between 3-6mm. The length of the first tab 1 or the length of the second tab 2 is preferably in the range of 400-600mm, for example, the length of the first tab 1 can be 100mm, 150mm, 200mm, 250mm, 300mm, 350mm, 450mm, 400mm, 500mm, 550mm, 600mm.
[0049] The diameter of the winding core manufactured in the present embodiment can be in the range of 8.0-14.0mm, and the diameter of the winding core is preferably 10mm-14.0mm.
[0050] According to the different designs of the winding core diameter and the tab angle, the difference between the total length of the positive and negative tabs is distributed between 10-80mm.
[0051] Referring to Figure 4 and Figure 5 In an embodiment, the first foil 11 is a copper foil, and the second foil 21 is an aluminum foil. The extension piece 4 is an aluminum foil, and the extension piece 4 and the second foil 21 are integrally formed. Similarly, the extension piece 4 and the first foil 11 are integrally formed in the previous embodiment, which will not be described here.
[0052] As an example, the winding angle of the extension piece 4 is greater than 360°, and the winding angle of the extension piece 4 is greater than 360°, and when winding, the outer end of the extension piece 4 exceeds the second tab 8, and the length of the extension piece 4 exceeding the second tab 8 is greater than 1mm. Similarly, the extension piece 4 and the first foil 11 are integrally formed in the previous embodiment, which will not be described here.
[0053] In an embodiment, the utility model further provides a battery, which comprises a shell and the winding core described above, and the winding core is arranged in the shell.
[0054] The above-described embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.
Claims
1. A core, characterized in that, The first pole piece (1), the second pole piece (2), the diaphragm (3), the extension piece (4) and the end paper (6) are included, the diaphragm (3) is arranged between the first pole piece (1) and the second pole piece (2), the diaphragm (3) is arranged on the side of the first pole piece (1) away from the second pole piece (2) and / or the side of the second pole piece (2) away from the first pole piece (1), the first pole piece (1), the second pole piece (2) and the diaphragm (3) are wound to form a core body; one of the first pole piece (1) and the second pole piece (2) is a positive pole piece, and the other is a negative pole piece; The first pole piece (1) includes a first foil piece (11) and a first active layer (12) coated on the first foil piece (11), and the second pole piece (2) includes a second foil piece (21) and a second active layer (22) coated on the second foil piece (21); The length of the first pole piece (1) is greater than the length of the second pole piece (2), the outer end of the first foil piece (11) or the outer end of the second foil piece (21) is connected with the inner end of the extension piece (4), the extension piece (4) is wound outside the core body, and the extension piece (4) is wound at least once; The length of the diaphragm (3) is greater than the length of the first pole piece (1), and the part of the diaphragm (3) exceeding the first pole piece (1) is wound together with the extension piece (4) to form a spacer (5), and the outer end of the spacer (5) is wound outside the extension piece (4); The end paper (6) is annular, and the end paper (6) is wound outside the spacer (5).
2. The core of claim 1, wherein The length of the spacer (5) is greater than the length of the extension piece (4).
3. The core of claim 1, wherein It also includes a first tab (7) and a second tab (8), the first tab (7) is welded on the first foil piece (11), and the second tab (8) is welded on the second foil piece (21); The first tab (7) is close to the outer end of the first foil piece (11), and the second tab (8) is close to the outer end of the second foil piece (21).
4. The core according to claim 3, wherein The first foil piece (11) is a copper foil, and the second foil piece (21) is an aluminum foil; the extension piece (4) is a copper foil piece; The extension piece (4) and the first foil piece (11) are integrally formed.
5. The core of claim 4, wherein The winding angle of the extension piece (4) is greater than 360°, the first tab (7) is located on the inner side of the extension piece (4), the outer end of the extension piece (4) exceeds the first tab (7), and the length of the extension piece (4) exceeding the first tab (7) is greater than 1mm.
6. The core according to claim 3, wherein The first foil piece (11) is a copper foil, and the second foil piece (21) is an aluminum foil; the extension piece (4) is an aluminum foil piece, and the extension piece (4) and the second foil piece (21) are integrally formed.
7. The core of claim 6, wherein The winding angle of the extension tab (4) is greater than 360°, the second tab (8) is located on the inner side of the extension tab (4), the outer end of the extension tab (4) exceeds the second tab (8), and the length of the extension tab (4) exceeding the second tab (8) is greater than 1 mm.
8. The core of claim 1, wherein The width of the first tab (1) is greater than the width of the second tab (2).
9. The core of claim 8, wherein The difference between the width of the first tab (1) and the width of the second tab (2) is greater than 0.3 mm.
10. The core of claim 8, wherein The width of one of the first tab (1) and the second tab (2) ranges from 3 mm to 40 mm.
11. The core of claim 1, wherein The length of one of the first tab (1) and the second tab (2) ranges from 100 mm to 600 mm.
12. A battery, characterized by The application further discloses a battery, which comprises a shell and the winding core according to any one of claims 1-11, and the winding core is arranged in the shell.