CN212625655U

CN212625655U - Lithium battery roll core and lithium ion battery thereof

Info

Publication number: CN212625655U
Application number: CN202021512533.5U
Authority: CN
Inventors: 郑杰龙
Original assignee: Dongguan Adf Battery Co ltd
Current assignee: Dongguan Adf Battery Co ltd
Priority date: 2020-07-27
Filing date: 2020-07-27
Publication date: 2021-02-26
Anticipated expiration: 2030-07-27

Abstract

The utility model discloses a lithium battery roll core, and a lithium battery with lithium battery roll core is disclosed, wherein lithium battery roll core includes the anode strip, negative pole piece and barrier film, be provided with the positive pole ear on the anode strip, the positive pole ear includes first positive utmost point ear and second positive utmost point ear, first positive utmost point ear and second positive pole ear are located positive pole piece length direction's quarter department and three departments of quarter respectively, be provided with negative pole ear on the negative pole piece, the negative pole ear includes first negative utmost point ear and second negative utmost point ear, first negative utmost point ear and second negative pole ear are located negative pole piece length direction's quarter department and three departments of quarter respectively, be provided with the barrier film between positive pole piece and the negative pole piece, barrier film and positive pole piece coiling setting. Through the utility model discloses a core is rolled up to the lithium cell, can make the internal resistance reduce to place the fourth in the pole piece of pole piece one end department with single utmost point ear to reduce the heat that rolls up the core production, and improve the discharge performance that the core was rolled up to the lithium cell.

Description

Lithium battery roll core and lithium ion battery thereof

Technical Field

The utility model relates to a lithium ion battery's technical field, in particular to lithium cell rolls up core and lithium ion battery thereof.

Background

The lithium ion battery is a general term of a battery taking a lithium ion intercalation compound as a positive electrode material, has the characteristics of high energy density, no memory effect, excellent cycle performance and quick charge and discharge, and is a green energy battery with high output power, long service life and no environmental pollution. The lithium ion battery comprises a digital lithium ion battery, the digital lithium ion battery adopts a winding structure, but the internal resistance of the polymer battery manufactured according to the structure is higher, and the rate capability is insufficient.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a core is rolled up to lithium cell under the same external condition, the internal resistance of single pole piece and utmost point ear is unchangeable, can reduce the internal resistance to single utmost point ear place in the quarter of the core is rolled up to the lithium cell of pole piece one end department, improves the discharge performance that the core was rolled up to lithium cell.

The utility model also provides a lithium ion battery of having above-mentioned lithium cell book core.

The anode piece is provided with anode lugs, the anode lugs comprise a first anode lug and a second anode lug, the first anode lug is positioned at one fourth of the length direction of the anode piece, and the second anode lug is positioned at three quarters of the length direction of the anode piece;

the cathode sheet is provided with cathode tabs, the cathode tabs comprise a first cathode tab and a second cathode tab, the first cathode tab is positioned at one fourth of the length direction of the cathode sheet, and the second cathode tab is positioned at three fourths of the length direction of the cathode sheet;

the isolating film is arranged between the anode sheet and the cathode sheet, the isolating film and the anode sheet are wound.

According to the utility model discloses lithium cell rolls up core has following beneficial effect at least: the pole piece is provided with two tabs, so that the pole piece and the tabs are connected in parallel when the lithium battery works, and the internal resistance of the pole piece provided with the two tabs is one half of the internal resistance of the pole piece provided with one tab according to the characteristics of a parallel circuit; according to a defined formula of the resistance, the first anode lug is arranged at the quarter of the anode sheet, the second anode lug is arranged at the three-quarter of the anode sheet, the first cathode lug is arranged at the quarter of the cathode sheet, and the second cathode lug is arranged at the three-quarter of the cathode sheet, so that the internal resistances of the anode sheet and the cathode sheet are reduced by one half, the cathode sheet, the isolating film and the anode sheet form a lithium battery roll core after being wound, and compared with the lithium battery roll core with a single lug arranged at one end of the pole sheet, the lithium battery roll core can reduce the internal resistance to the quarter of the pole sheet arranged at one end of the pole sheet, thereby reducing the heat generated by the roll core and improving the discharge performance of the lithium battery roll core.

According to some embodiments of the invention, the first positive tab and the second positive tab are both arranged on the same face of the positive plate.

According to some embodiments of the invention, the first female tab and the second female tab are both disposed on the same face of the cathode sheet.

According to some embodiments of the present invention, the anode sheet is provided with an anode coating, and the anode coating is distributed on the anode sheet at intervals.

According to some embodiments of the invention, the cathode plate is provided with a cathode coating, and the cathode coating is distributed on the cathode plate at intervals.

According to some embodiments of the invention, the anode sheet welds the anode tab department with the cathode sheet welds the cathode tab department all is provided with green glue.

According to some embodiments of the present invention, the anode sheet is wound around the coil and the first anode tab corresponds to the position of the second anode tab, and the cathode sheet is wound around the coil and the first cathode tab corresponds to the position of the second cathode tab.

According to some embodiments of the present invention, the width of the anode tab is 5-15mm, the thickness is 0.1-0.2mm, and the length of the anode tab portion beyond the anode sheet is 10-20 mm.

According to some embodiments of the invention, the width of the cathode tab is 5-15mm, the thickness is 0.1-0.2mm, and the length of the cathode tab beyond the cathode plate portion is 10-20 mm.

According to the utility model discloses a lithium ion battery of second aspect embodiment, include according to the utility model discloses the lithium cell of above-mentioned first aspect embodiment rolls up the core.

According to the utility model discloses lithium ion battery has following beneficial effect at least: by adopting the lithium battery roll core, the internal resistance of the lithium battery roll core is reduced to one fourth of the pole piece with a single pole lug arranged at one end of the pole piece, so that the problem of overheating of a large-current discharge theme of a battery is solved, and the service life and the reliability of the lithium battery in recycling are improved.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural diagram of a front surface of an anode sheet of a lithium battery roll core according to an embodiment of the present invention;

fig. 2 is a schematic structural view of the reverse side of the anode sheet of the lithium battery roll core in the embodiment of the present invention;

fig. 3 is a schematic structural diagram of the front side of the lithium battery roll core cathode plate according to the embodiment of the present invention;

fig. 4 is the schematic diagram of the structure of the reverse side of the lithium battery roll core cathode plate of the embodiment of the present invention.

Reference numerals:

anode sheet 110, first anode tab 111, second anode tab 112, anode paint 113, first gap 114, cathode sheet 120, first cathode tab 121, second cathode tab 122, cathode paint 123, second gap 124, green glue 130.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated with respect to the orientation description, such as up, down, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, a plurality of means are one or more, a plurality of means are two or more, and the terms greater than, less than, exceeding, etc. are understood as not including the number, and the terms greater than, less than, within, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless there is an explicit limitation, the words such as setting, installation, connection, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in combination with the specific contents of the technical solution.

The lithium battery roll core according to the present invention is described below with reference to fig. 1 to 4.

As shown in fig. 1 to 4, the lithium battery roll core according to the embodiment of the first aspect of the present invention includes: an anode sheet 110, a cathode sheet 120, and a separator.

The anode sheet 110 is provided with an anode tab, the anode tab comprises a first anode tab 111 and a second anode tab 112, the first anode tab 111 is located at one quarter of the length direction of the anode sheet 110, and the second anode tab 112 is located at three quarters of the length direction of the anode sheet 110; the cathode sheet 120 is provided with cathode tabs, the cathode tabs comprise a first cathode tab 121 and a second cathode tab 122, the first cathode tab 121 is located at one fourth of the length direction of the cathode sheet 120, and the second cathode tab 122 is located at three fourths of the length direction of the cathode sheet 120; the separator is provided between the anode sheet 110 and the cathode sheet 120, the separator and the anode sheet 110 are wound.

Specifically, two tabs are respectively arranged on the anode sheet 110 and the cathode sheet 120, which is equivalent to parallel connection of the tabs and the pole pieces when the battery works, and according to the characteristics of a parallel circuit, the internal resistance of the two tabs is set to be half of that of the single tab; simultaneously, place first positive pole ear 111 in the quarter department of positive pole piece 110 length direction and place second positive pole ear 112 in the three quarters department of positive pole piece 110 length direction, place first negative pole ear 121 in the quarter department of negative pole piece 120 length direction and place second negative pole ear 122 in the three quarters department of negative pole piece 120 length direction, be equivalent to equally divide into two parts with a pole piece, every utmost point ear is placed in the center department of every part pole piece, according to the definition formula of resistance, the internal resistance through the pole piece that so sets up compares in setting up two utmost point ears in the internal resistance at pole piece both ends and has reduced half, consequently, the internal resistance of pole piece in the embodiment of the utility model provides an is that single utmost point ear is placed in the quarter of the internal resistance of the pole piece of pole piece one end. The cathode sheet 120, the separator, and the anode sheet 110 are wound, the cathode sheet 120 is disposed at the innermost side, and the separator is disposed between the cathode sheet 120 and the anode sheet 110.

In some embodiments of the present invention, the first and

second anode tabs

111 and 112 are disposed on the same face of the anode sheet 110. For example, as shown in fig. 1 to 4, the first and

second anode tabs

111 and 112 are provided on the same surface of the anode sheet 110. Specifically, by disposing the two first and

second anode tabs

111 and 112 on the same surface of the anode sheet 110, the anode sheet 110 is facilitated to complete a subsequent winding action.

In some embodiments of the present invention, the first and

second cathode tabs

121 and 122 are disposed on the same surface of the cathode sheet 120. For example, as shown in fig. 1 to 4, the first and

second cathode tabs

121 and 122 are disposed on the same surface of the cathode sheet 120. Specifically, the first cathode tab 121 and the second cathode tab 122 are both disposed on the same surface of the cathode sheet 120, so that the cathode sheet 120 can be conveniently wound, and when the cathode sheet 120, the isolation film and the anode sheet 110 are simultaneously wound, the coating on the electrode sheet is prevented from adhering to the electrode tabs.

In some embodiments of the present invention, the anode strip 110 is provided with the anode coating 113, and the anode coating 113 is distributed on the anode strip 110 at intervals. For example, as shown in fig. 1 to 4, the anode sheet 110 is provided with the anode paint 113, and the anode paint 113 is distributed on the anode sheet 110 at intervals. Specifically, the anode coating 113 is an anode active material formed by mixing graphite, sodium carboxymethyl cellulose, a binder, a conductive agent, and deionized water; by coating the anode coating 113 on the anode sheet 110, electrons can be conveniently directionally moved on the current collector, lithium ions move to the anode during charging and synthesize lithium atoms with the electrons, the lithium atoms are ionized into lithium ions and electrons on the surface of the anode during discharging, and the anode sheet 110 and the cathode sheet 120 are matched to complete the charging and discharging of the lithium ion battery. The anode coating 113 needs to be distributed on the anode sheet 110 at intervals because the tab welded on the pole piece should be avoided from being provided with coating, and the portion of the anode sheet 110 not coated with the anode coating 113 is the first gap 114 for welding the anode tab on the anode sheet 110. When the anode coating 113 is coated, a continuous coating mode can be adopted, and after the pole piece is cut, the anode coating 113 is cleaned at the position corresponding to the pole lug through a laser cleaning technology; the anode coating 113 can be coated in a jumping interval mode, and gaps are reserved at the positions where the tabs are arranged and the positions corresponding to the tabs directly, so that the tabs are welded to the pole pieces, and meanwhile, the cathode sheet 120, the isolation film and the anode sheet 110 are convenient to wind.

In some embodiments of the present invention, the cathode sheet 120 is provided with the cathode coating 123, and the cathode coating 123 is distributed on the cathode sheet 120 at intervals. For example, as shown in fig. 1 to 4, the cathode sheet 120 is provided with a cathode coating 123, and the cathode coating 123 is distributed on the cathode sheet 120 at intervals. Specifically, the cathode coating 123 is a cathode active material formed by mixing lithium iron phosphate, a binder, a conductive agent and N-methylpyrrolidone, wherein the lithium iron phosphate can also be replaced by lithium cobaltate, electrons can be conveniently directionally moved on a current collector by uniformly coating the cathode coating 123 on the cathode sheet 120, lithium atoms in a cathode are ionized into lithium ions and electrons during charging, the lithium atoms are synthesized at the cathode during discharging, and the cathode sheet 120 and the anode sheet 110 are matched to complete the charging and discharging of the lithium ion battery. The cathode coating 123 is not required to be arranged on the tab welded on the pole piece, and the part of the cathode sheet 120 coated with the cathode coating 123 is the second gap 124, so the cathode coating 123 is required to be distributed and coated on the cathode sheet 120 at intervals. The continuous coating mode can be adopted, and after the pole piece is cut, the cathode coating 123 is cleaned at the position corresponding to the pole lug through a laser cleaning technology; the cathode coating 123 can be coated in a jumping interval mode, and gaps are reserved at the positions where the pole lugs are arranged and the positions corresponding to the pole lugs directly, so that the pole lugs are welded on the pole pieces, and meanwhile, the cathode sheet 120, the isolation film and the anode sheet 110 are convenient to wind.

In some embodiments of the present invention, the anode tab welded by the anode sheet 110 and the cathode tab welded by the cathode sheet 120 are both provided with green glue 130. For example, as shown in fig. 1 to 4, green tapes 130 are disposed at the anode tab welded position of the anode sheet 110 and the cathode tab welded position of the cathode sheet 120. Specifically, the green adhesive 130 is pasted at the position where the anode sheet 110 is provided with the anode tab and the position where the cathode sheet 120 is provided with the cathode tab, so that the problem that the tab welded on the pole piece is short-circuited due to burrs can be avoided, the normal use of the lithium battery winding core is ensured, and the service life of the lithium battery winding core is prolonged. The green glue 130 is an insulating adhesive tape, adopts a polypropylene insulating material as a base material, and is coated with acrylic acid glue special for the electrolyte of the endurance cell, so that the polar ear is insulated and fixed, and the problem of short circuit is avoided.

In some embodiments of the present invention, the anode sheet 110 is wound to correspond to the position of the first anode tab 111 and the second anode tab 112, and the cathode sheet 120 is wound to correspond to the position of the first cathode tab 121 and the second cathode tab 122. Specifically, the wound lithium battery roll core needs to weld two anode tabs on the anode sheet 110 together and two cathode tabs on the cathode sheet 120 together, so that the pole pieces can be normally used subsequently, in order to weld the two anode tabs together and the two cathode tabs together, the positions of the first anode tab 111 and the second anode tab 112 after winding need to be corresponding, and the positions of the first cathode tab 121 and the second cathode tab 122 need to be corresponding. In the winding process, the cathode sheet 120 is disposed at the innermost side, the anode sheet 110 is disposed at the outermost side, and the separator is disposed between the cathode sheet 120 and the anode sheet 110.

In some embodiments of the present invention, the width of the anode tab is 5-15mm, the thickness is 0.1-0.2mm, and the length of the anode tab exceeding the anode sheet 110 is 10-20 mm. Specifically, the cross-sectional area of the anode lug on the anode sheet can be adjusted by setting the anode lug to different widths and thicknesses, so that the safe current-carrying size of the lithium battery winding core is adjusted, when the anode lug is embedded on the anode sheet 110, the length of the part of the anode lug exceeding the anode sheet is 10-20mm, and the part of the anode lug exceeding the anode sheet 110, namely the part without contact between the anode lug and the anode sheet, can be convenient for welding the first anode lug and the second anode lug together after the anode sheet is wound. It is understood that the width and thickness of the anode tab and the length of the portion of the anode tab exceeding the anode sheet 110 can be adjusted according to actual needs, and it is not a specific limitation of the present invention to set the width of the anode tab and the cathode tab to 5-15mm, the thickness to 0.1-0.2mm, and the length of the portion of the anode tab exceeding the anode sheet 110 to 10-20mm in this embodiment.

In some embodiments of the present invention, the width of the cathode tab is 5-15mm, and the length of the cathode tab exceeding the cathode plate is 10-20mm, wherein the cathode tab has a thickness of 0.1-0.2 mm. Specifically, by setting the cathode tabs to different widths and thicknesses, the cross-sectional area of the cathode tabs on the cathode sheet 120 can be adjusted, thereby adjusting the safe current-carrying size of the lithium battery roll core; the cathode tab is embedded on the cathode sheet, the length of the cathode tab exceeding the cathode sheet is 10-20mm, and the part of the anode tab exceeding the cathode sheet, namely the part of the cathode tab not contacted with the cathode sheet 120, can be convenient for welding the first cathode tab 121 and the second cathode tab 122 together after the cathode sheet 120 is wound. When the square aluminum shell battery is manufactured, the anode lug can be conveniently welded on the aluminum cover plate. It is understood that the width and thickness of the cathode ear and the length of the cathode ear beyond the cathode sheet can be adjusted according to actual needs, and it is not a specific limitation of the present invention to set the width of the cathode ear and the cathode ear to 5-15mm, the thickness to 0.1-0.2mm and the length of the cathode ear beyond the cathode sheet 120 to 10-20mm in this embodiment.

According to the utility model discloses lithium ion battery of second aspect embodiment, include according to the utility model discloses the lithium cell of the aforesaid first aspect embodiment rolls up the core.

According to the utility model discloses lithium ion battery, through adopting foretell lithium cell to roll up the core, because of the internal resistance that the lithium cell rolled up the core reduces to setting up the fourth in the pole piece of pole piece one end department with single utmost point ear, has solved the overheated problem of battery heavy current main part that discharges, has improved life-span and the reliability of lithium ion battery cycle use.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.

Claims

1. A lithium battery roll core is characterized by comprising:

2. The lithium battery jelly roll of claim 1, wherein the first anode tab and the second anode tab are both disposed on the same face of the anode sheet.

3. The lithium battery jelly roll of claim 1, wherein the first cathode tab and the second cathode tab are both disposed on the same face of the cathode sheet.

4. The lithium battery winding core according to claim 1, wherein the anode sheet is provided with anode paint, and the anode paint is distributed on the anode sheet at intervals.

5. The lithium battery jelly roll of claim 1, wherein the cathode sheet has a cathode coating disposed thereon, the cathode coating being spaced apart on the cathode sheet.

6. The lithium battery winding core according to claim 1, wherein green glue is arranged at the anode tab welding position and the cathode tab welding position.

7. The lithium battery jelly roll of claim 1, wherein the first anode tab corresponds in position to the second anode tab after the anode sheet is wound, and the first cathode tab corresponds in position to the second cathode tab after the cathode sheet is wound.

8. The lithium battery jelly roll of claim 1, wherein the anode tab has a width of 5-15mm and a thickness of 0.1-0.2mm, and the anode tab has a length exceeding the anode sheet by 10-20 mm.

9. The lithium battery jelly roll of claim 1, wherein the cathode tab has a width of 5-15mm and a thickness of 0.1-0.2mm, and the portion of the cathode tab beyond the cathode sheet has a length of 10-20 mm.

10. A lithium ion battery, characterized in that it comprises a lithium battery jelly roll according to any of claims 1 to 9.