CN213660479U

CN213660479U - Multi-tab winding battery

Info

Publication number: CN213660479U
Application number: CN202022177186.1U
Authority: CN
Inventors: 朱伯礼; 鄢翔; 于子龙; 杨山; 陈杰; 李载波
Original assignee: Huizhou Liwinon Energy Technology Co Ltd
Current assignee: Huizhou Liwinon Energy Technology Co Ltd
Priority date: 2020-09-29
Filing date: 2020-09-29
Publication date: 2021-07-09
Anticipated expiration: 2030-09-29

Abstract

The utility model provides a multi-tab winding battery, which comprises an electric core formed by winding a first pole piece, a diaphragm and a second pole piece, wherein the polarities of the first pole piece and the second pole piece are opposite; the first pole piece comprises a first current collector, and a first lug and a second lug are connected to the first current collector; the first tab is welded on the first current collector, and the second tab and the first current collector are integrally formed; the second pole piece comprises a second current collector, and a third pole lug and a fourth pole lug are connected to the second current collector; the third electrode lug is welded on the second current collector, and the fourth electrode lug and the second current collector are integrally formed. Compared with the prior art, the battery adopts a multi-tab design, the two added tabs adopt a mode of integrally forming with a current collector, so that the battery is not required to be covered with protective glue on the surface, the problem of reducing the energy density of the battery due to the fact that the tab is newly added to be pasted with the protective glue is solved, an electronic transmission path is reduced, the charging speed of the battery is improved, and the charging temperature rise is reduced.

Description

Multi-tab winding battery

Technical Field

The utility model relates to a lithium cell field, concretely relates to multi-tab winding battery.

Background

In the current mobile phone market, the update of the mobile phone is faster and faster, and besides the improvement of the application function and performance of the mobile phone, the fast charging, longer endurance and lower heating phenomenon of the mobile phone are also important upgrading indexes in the update. As the screen of the mobile phone tends to be designed widely, the energy consumption is higher and higher, and the capacity of a single battery is inevitably required to be higher and higher; the capacity of a quick-charging battery on the mobile phone market in 2015-2018 is mainly 3 Ah-4 Ah, the capacity of the quick-charging battery in 2018 is increased to 4 Ah-5 Ah, and part of items are increased to 6 Ah; the energy density of the lithium battery mainly adopting a lithium cobaltate-graphite system at the present stage is improved qualitatively; this requires the battery to be larger and larger to increase the battery capacity; the charging multiplying power of the quick charging battery is synchronously improved, and the charging power of the mobile phone is improved by more than one time; for the battery with the conventional winding structure, the capacity is large, the charging power is large, the internal polarization of the battery is large, the charging speed is slow, the temperature rise of the battery is too large, and the use experience of a customer is influenced, so that the internal polarization of the battery is reduced by improving the battery design, the charging temperature rise of the battery is reduced, and the charging efficiency is improved.

Along with the volume and capacity of the lithium battery of the mobile phone, a battery supplier reduces the transmission path and impedance of electrons by welding the middle parts of the coating areas (the cathode and the anode are both designed with one tab) of the pole pieces of the cathode and the anode aiming at the battery design of a winding structure at present, reduces the internal resistance of the battery, and shows the effects of high charging speed and low temperature rise on the battery products, a small number of high-end products in the market at present have the design applied to the type, and the battery products are mainly quick-charging batteries within 1.5C and 2C; along with the development trend of batteries, the capacity is larger, the pole piece is longer, the conduction path is increased, the quick charge rate is improved to 3C and 5C, the polarization used is increased, the tab middle design of a single tab cannot meet the future requirement, if the similar design only increases the number of the tabs, the activity coating loss can be caused by the increase of the number of the attached protective glue, and the energy density is obviously reduced. In order to meet the requirements of future development, the design of the battery structure needs to be further improved to achieve the purposes of improving the charging speed and reducing the temperature rise, and simultaneously reducing the loss of energy density.

In view of the above, it is necessary to provide a technical solution to the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a: a multi-tab winding battery solves the problem that the existing tab middle-arranged structure cannot meet the requirements of higher capacity and higher charging rate; the utility model provides a many utmost point ear design not only can improve the charge rate of battery and reduce the temperature rise of charging, and need not to coat the district again and paste the protection and glue, has avoided energy density's loss.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a multi-tab winding battery comprises a battery core formed by winding a first pole piece, a diaphragm and a second pole piece, wherein the first pole piece and the second pole piece have opposite polarities,

the first pole piece comprises a first current collector, and a first tab and a second tab are connected to the first current collector; the first tab is welded to the first current collector, and the second tab and the first current collector are integrally formed;

the second pole piece comprises a second current collector, and a third pole lug and a fourth pole lug are connected to the second current collector; the third electrode lug is welded on the second current collector, and the fourth electrode lug and the second current collector are integrally formed.

Preferably, in the length direction of the first pole piece, a first active material region is coated on the first current collector, and the first pole lug and the second pole lug are both led out from the first active material region; in the length direction of the second pole piece, a second active material area is coated on the second current collector, and the third tab and the fourth tab are respectively led out from the second active material area.

Preferably, the fourth tab corresponds to the first tab, and the second tab corresponds to the third tab.

Preferably, the first tab is disposed at a position 1/5-1/3 in the longitudinal direction of the first pole piece, and the third tab is disposed at a position 1/5-1/3 in the longitudinal direction of the second pole piece.

Preferably, the second pole piece is arranged at 2/3-4/5 positions in the length direction of the first pole piece, and the fourth pole piece is arranged at 2/3-4/5 positions in the length direction of the second pole piece.

Preferably, the width of the second tab is 1.5-3 times that of the first tab; the width of the fourth electrode lug is 1.5-3 times of that of the third electrode lug.

Preferably, in the battery core, the exposed lengths of the second tab and the fourth tab are both 3-5 mm.

Preferably, in the battery cell, the first tab is electrically connected to the second tab, and the third tab is electrically connected to the fourth tab.

Preferably, the first active material region is provided with a first empty foil region by at least one of a laser cleaning method, a solvent cleaning method, a pre-coating polymer method and a pre-gummed paper method, and the first tab is welded to the first empty foil region.

Preferably, the second active material region is provided with a second empty foil region by at least one of a laser cleaning method, a solvent cleaning method, a pre-coating polymer method, and a pre-pasting paper method, and the third tab is welded to the second empty foil region.

Compared with the prior art, the beneficial effects of the utility model reside in that: the winding battery of the utility model adopts a multi-pole ear design, and two added pole ears are integrally formed with the current collector, namely, a part of area is extended out of the edge of the current collector to be used as a second pole ear and is used as a pole piece leading-out end together with the welded pole ear; in addition, the multi-lug design of the battery further reduces an electronic transmission path and impedance, so that the charging speed of the battery is improved, the charging temperature rise is reduced, and the requirements of higher capacity and higher charging rate are met.

Drawings

Fig. 1 is the front schematic view of the pole piece before connecting the tab.

Fig. 2 is the side schematic view of the pole piece before connecting the tab.

Fig. 3 is the front schematic view of the pole piece after connecting the tab.

Fig. 4 is the side schematic view of the pole piece after connecting the tab.

Fig. 5 is a schematic view illustrating the connection between the first tab and the second tab of the present invention.

Fig. 6 is a schematic view of the third tab connected to the fourth tab.

In the figure: 1-a first pole piece; 11-a first current collector; 12-a first empty foil area; 13-a first active material region; 14-a first tab; 15-a second tab; 16-the tail of the first pole piece; 2-a first pole piece; 21-a second current collector; 22-a second empty foil area; 23-a second active material region; 24-a third tab; 25-a fourth tab; 26-the head of the second pole piece; 3-an intermediate conductor; 4-a separator; 5-protective glue.

Detailed Description

In order to make the technical solutions and advantages of the present invention clearer, the present invention and its advantageous effects will be described in further detail below with reference to the accompanying drawings of the detailed description and the specification, but the present invention is not limited thereto.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "fixed" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The utility model discloses the standard part that uses all can purchase from the market, and dysmorphism piece all can be customized according to the description with the record of drawing of description, and the concrete connection mode of each part all adopts conventional means such as ripe bolt, rivet, welding among the prior art, and machinery, part and equipment all adopt prior art, and conventional model, including circuit connection adopts conventional connection mode among the prior art, does not detailed here again.

As shown in fig. 1 to 6, a multi-tab wound battery includes a battery core formed by winding a first pole piece 1, a diaphragm 4 and a second pole piece 2, wherein the first pole piece 1 and the second pole piece 2 have opposite polarities, the first pole piece 1 includes a first current collector 11, and the first current collector 11 is connected with a first tab 14 and a second tab 15; the first tab 14 is welded to the first current collector 11, and the second tab 15 is integrally formed with the first current collector 11; the second pole piece 2 comprises a second current collector 21, and a third lug 24 and a fourth lug 25 are connected to the second current collector 21; the third tab 24 is welded to the second current collector 21, and the fourth tab 25 is integrally formed with the second current collector 21. Specifically, the first tab 1 may be a positive tab, the second tab 2 may be a negative tab, the first tab 14 and the second tab 15 are both positive tabs, and the third tab 24 and the fourth tab 25 are both negative tabs. The second tab 15 can be obtained by exposing a part of a blank foil area of the first current collector 11 after laser die cutting or knife die cutting, the exposed blank foil area is regarded as the second tab 15, and the second tab 15 comprises at least one tab integrally formed with the first current collector 11, or a plurality of tabs can be arranged respectively; the fourth tab 25 is also obtained in that the fourth tab 25 also includes at least one tab integrally formed with the second current collector 21. Preferably, the fourth tab 25 is disposed corresponding to the first tab 14, and the second tab 15 is disposed corresponding to the third tab 24.

Further, in the length direction of the first pole piece 1, a first active material area 13 is coated on the first current collector 11, and both the first tab 14 and the second tab 15 are led out from the first active material area 13; in the length direction of the first pole piece 2, the second current collector 21 is coated with a second active material region 23, and both the third pole lug 24 and the fourth pole lug 25 are led out from the second active material region 23. The first tab 14 and the third tab 24 are used as main tabs, the second tab 15 and the fourth tab 25 are used as auxiliary tabs, the second tab 15 and the fourth tab 25 are led out by extending the edge part of a current collector, and the active material area attached protective adhesive 5 at the corresponding position of the second tab and the fourth tab is not needed, so that the energy loss caused by tab increase is avoided, meanwhile, the path of electronic transmission is effectively reduced by the tab increase, the charging speed is improved, and the charging temperature rise is reduced.

Furthermore, the first tab 14 is arranged at the position 1/5-1/3 in the length direction of the first pole piece 1, and the third tab 24 is arranged at the position 1/5-1/3 in the length direction of the second pole piece 2. The second tab 15 is disposed at 2/3-4/5 positions in the length direction of the first pole piece 1, and the fourth tab 25 is disposed at 2/3-4/5 positions in the length direction of the second pole piece 2. The first lug 14 and the second lug 15 are respectively arranged at two ends of the first pole piece 1 and are matched with the fourth lug 25 and the third lug 24, so that the path of electron transmission can be effectively reduced, the charging speed is further improved, and the charging temperature rise is further reduced. In an actual winding structure, a single-sided empty foil area is generally arranged at the tail of the positive plate, and a single-sided empty foil area is arranged at the head of the negative plate, so that if the first pole piece 1 is the positive plate, the position close to the first pole lug 14 is the head position of the first pole piece, and the position close to the second pole lug 15 is the tail 16 position of the first pole piece; if the second pole piece 2 is a negative pole piece, the position close to the third pole piece 24 is the head part 26 of the second pole piece, and the position close to the fourth pole piece 25 is the tail part of the second pole piece.

Further, the width of the second tab 15 is 1.5 to 3 times of the width of the first tab 14; the width of the fourth tab 25 is 1.5-3 times of the width of the third tab 24. The widths of the second lug 15 and the fourth lug 25 are increased, and the lugs at the two positions are formed by laser or cutting die, so that the increased widths of the lugs at the two positions are more favorable for actual production operation, and in addition, the subsequent welding with the first lug 14 or the third lug 24 is also favorable.

Further, in the battery core, the exposed lengths of the second lug 15 and the fourth lug 25 are both 3-5 mm. The second tab 15 and the fourth tab 25 are exposed to a length smaller than the first tab 14 and the third tab 24 with respect to the tabs of the conventional narrow battery, which is a length exceeding the separator 4 in the cell.

Further, in the battery cell, the first tab 14 is electrically connected to the second tab 15, and the third tab 24 is electrically connected to the fourth tab 25. Specifically, the first tab 14 and the second tab 15 may be welded together using the intermediate conductor 3, and similarly, the third tab 24 and the fourth tab 25 may be welded together using the intermediate conductor 3.

In actual pole piece production, the exposed length of the second pole piece 15 is shorter than that of the first pole piece 14, and the exposed length of the second pole piece 15 can be increased by using the intermediate conductor 3 connected between the two so that the second pole piece 15 is electrically connected with the first pole piece 14. Likewise, the connection of the third tab 24 and the fourth tab 25 is also the same. However, in the actual production of the battery core, due to the influence of process fluctuation, the positions of the first tab 14 and the second tab 15 or the positions of the third tab 24 and the fourth tab 25 cannot be completely aligned after being wound, the first tab and the second tab 24 or the third tab 24 and the fourth tab 25 need to be connected by the intermediate conductor 3, when the intermediate conductor 3 is welded, the intermediate conductor 3 needs to be in a vertical state, otherwise, the welding is difficult, but the two tabs cannot be aligned to cause the welding difficulty of the intermediate conductor 3, and the increased width of the second tab 15 and the fourth tab 25 of the battery can effectively solve the problem that the two tabs cannot be aligned to cause the welding difficulty. In the specific welding, the intermediate conductor 3 can be connected to the first tab 14, and then the second tab 15 is butted; likewise, so does the third and

fourth ears

24 and 25.

Further, the first active material region 13 is provided with the first empty foil region 12 by at least one of a laser cleaning method, a solvent cleaning method, a pre-coating polymer method, and a pre-gummed paper method, and the first tab 14 is welded to the first empty foil region 12. The pre-gummed paper method and the pre-coating polymer layer method are to pre-gummed paper or pre-coating a polymer layer at a designated position, and then to make substances in the designated position fall off by cold pressing or baking, so as to form a second hollow foil area 22; the laser cleaning and solvent cleaning method is to clean part of active matter through laser or solvent or both, the tab forms tab slot with certain shape, and then the tab is welded to the slot and led out. Preferably, a laser cleaning method is adopted to remove part of the first active material region 13, and then a first empty foil region 12 with a certain shape is reserved as a groove of the first tab 14. When the first tab 14 is a positive tab, an aluminum sheet is welded in the slot of the first tab 14 to lead out the positive tab.

Further, the second active material region 23 is provided with a second empty foil region 22 by at least one of a laser cleaning method, a solvent cleaning method, a pre-coating polymer method, and a pre-gummed paper method, and the third tab 24 is welded to the second empty foil region 22. Preferably, a laser cleaning method is used to remove a portion of the second active material region 23, so as to reserve a second empty foil region 22 with a certain shape as a third tab 24 slot. When the third tab 24 is a negative tab, a copper sheet or a nickel sheet is welded in the slot of the third tab 24 to lead out the negative tab.

The specific preparation method of the battery comprises the following steps:

1) coating a first active material in a first current collector 11 to form a large first pole piece 1, and coating a second active material in a second current collector 21 to form a large second pole piece 2; the large first pole piece 1 and the large second pole piece 2 are rolled and stripped to form the small first pole piece 1 and the small second pole piece 2, namely the pole pieces of the normal battery.

2) And cleaning a first empty foil area 12 for welding the first tab 14 at the head 1/5-1/3 positions of the first pole piece by a laser cleaning and solvent adding method, and cleaning a second empty foil area 22 for welding the third tab 24 at the head 1/5-1/3 positions of the second pole piece by a laser cleaning method.

3) Cutting second lugs 15 on the first current collector 11 at positions which are far from the head portions 2/3-4/5 of the first pole piece by a laser die cutting or knife die cutting method, and cutting fourth lugs 25 on the second current collector 21 at positions of the head portions 2/3-4/5 of the second pole piece by the laser die cutting or knife die cutting method; the width of the second tab 15 is 1.5-3 times of the width of the first tab 14, and the length of the second tab exceeds the length of the diaphragm 4 by 3-5 mm in the battery cell; the width of the fourth tab 25 is 1.5-3 times of the width of the third tab 24, and the length of the fourth tab exceeds the length of the diaphragm 4 in the battery cell by 3-5 mm.

4) Sticking a protective adhesive 5 on the first pole lug 14 and the third pole lug 24, and winding the processed first pole piece 1, the diaphragm 4 and the second pole piece 2 to form a naked battery cell; the first lug 14 and the second lug 15, and the third lug 24 and the fourth lug 25 are respectively connected through the intermediate conductor 3, the length of the second lug 15 is increased through the intermediate conductor 3 to enable the second lug to be flush with the top of the first lug 14, and similarly, the length of the fourth lug 25 is increased through the intermediate conductor 3 to enable the fourth lug to be flush with the top of the third lug 24, so that the multi-lug winding battery is prepared.

Variations and modifications to the above-described embodiments may become apparent to those skilled in the art from the disclosure and teachings of the above description. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious modifications, replacements or variations made by those skilled in the art on the basis of the present invention belong to the protection scope of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A multi-tab winding battery comprises a battery core formed by winding a first pole piece (1), a diaphragm (4) and a second pole piece (2), wherein the first pole piece (1) and the second pole piece (2) have opposite polarities,

the first pole piece (1) comprises a first current collector (11), and a first tab (14) and a second tab (15) are connected to the first current collector (11); the first electrode lug (14) is welded to the first current collector (11), and the second electrode lug (15) is integrally formed with the first current collector (11);

the second pole piece (2) comprises a second current collector (21), and a third tab (24) and a fourth tab (25) are connected to the second current collector (21); the third electrode lug (24) is welded on the second current collector (21), and the fourth electrode lug (25) and the second current collector (21) are integrally formed.

2. The multi-tab wound battery according to claim 1, characterized in that the first current collector (11) is coated with a first active material region (13) in the length direction of the first pole piece (1), and both the first tab (14) and the second tab (15) are led out from the first active material region (13); in the length direction of the second pole piece (2), a second active material area (23) is coated on the second current collector (21), and the third tab (24) and the fourth tab (25) are both led out from the second active material area (23).

3. The multi-tab wound battery according to claim 2, wherein the fourth tab (25) is disposed in correspondence with the first tab (14), and the second tab (15) is disposed in correspondence with the third tab (24).

4. The multi-tab wound battery according to claim 3, wherein the first tab (14) is disposed at 1/5-1/3 of the first pole piece (1) in the length direction, and the third tab (24) is disposed at 1/5-1/3 of the second pole piece (2) in the length direction.

5. The multi-tab wound battery according to claim 4, wherein the second tab (15) is disposed at 2/3-4/5 of the first pole piece (1) in the length direction, and the fourth tab (25) is disposed at 2/3-4/5 of the second pole piece (2) in the length direction.

6. The multi-tab wound battery according to any one of claims 1 to 5, wherein the width of the second tab (15) is 1.5 to 3 times the width of the first tab (14); the width of the fourth tab (25) is 1.5-3 times of the width of the third tab (24).

7. The multi-tab wound battery according to claim 6, wherein in the cell, the first tab (14) is electrically connected with the second tab (15), and the third tab (24) is electrically connected with the fourth tab (25).

8. The multi-tab wound battery according to claim 2, wherein the first active material region (13) is provided with a first empty foil region (12) by at least one of a laser cleaning method, a solvent cleaning method, a pre-coating polymer method, a pre-gummed paper method, and the first tab (14) is welded to the first empty foil region (12).

9. The multi-tab wound cell according to claim 8, wherein the second active material region (23) is provided with a second empty foil region (22) by at least one of a laser cleaning method, a solvent cleaning method, a pre-coating polymer method, and a pre-gummed paper method, and the third tab (24) is welded to the second empty foil region (22).