CN215731849U

CN215731849U - Battery negative plate lithium pre-preparing equipment

Info

Publication number: CN215731849U
Application number: CN202122113740.4U
Authority: CN
Inventors: 李强; 尹海旭; 刘道淦
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2021-09-02
Filing date: 2021-09-02
Publication date: 2022-02-01
Anticipated expiration: 2031-09-02

Abstract

The utility model provides a battery negative plate lithium pre-treatment device which comprises a lithium foil pre-treatment unit, a rolling unit and a base film removing unit which are sequentially arranged. The lithium foil pretreatment unit comprises a base film storage mechanism, a lithium foil storage mechanism and at least one pair of composite rollers, wherein a base film led out by the base film storage mechanism and a lithium foil led out by the lithium foil storage mechanism are pressed by the composite rollers to form a lithium-pretreatment composite layer. The rolling unit comprises a pole piece conveying mechanism and at least one pair of rolling rollers, a pre-lithium composite layer led out by the lithium foil pretreatment unit and a negative pole piece led in by the pole piece conveying mechanism are guided to be overlapped and are pressed by the rolling rollers to form a film-containing pre-lithium pole piece; and the base film is arranged on the surface of the film-containing pre-lithium pole piece, and the base film removing unit is used for removing the base film on the surface of the film-containing pre-lithium pole piece so as to form the pre-lithium pole piece. The battery negative plate pre-lithium device can carry out pre-lithiation treatment on the negative plate.

Description

Battery negative plate lithium pre-preparing equipment

Technical Field

The utility model relates to the technical field of lithium ion batteries, in particular to a battery negative plate lithium pre-preparing device.

Background

With the continuous improvement of the production technology and product performance of the lithium ion battery, the application field of the lithium ion battery is wider, and the high capacity, energy density and high safety become important in the research and development of the lithium ion battery. Graphite has been a well-established production process as a main lithium ion battery negative electrode material. The technology of lithium supplement by the negative electrode is a main way for improving the energy density, the cycle and the calendar life of the lithium ion battery.

In the prior art, the problem of uneven lithium supplement exists due to unreasonable structure of the lithium supplement equipment for the negative electrode, the phenomenon of uneven lithium ion distribution and uneven current density on the surface of the negative electrode in the subsequent formation and circulation processes can be caused due to uneven lithium supplement, and lithium precipitation due to overcharging is easy to occur in an area with high lithium ion concentration. In addition, the residual lithium metal caused by the failure of rapid and complete reaction of the lithium metal of the negative electrode has certain influence on the performance and safety of the battery.

SUMMERY OF THE UTILITY MODEL

In view of this, the present invention is directed to a device for pre-lithiating a negative electrode sheet of a battery, so as to provide a technical solution for pre-lithiating the negative electrode sheet.

In order to achieve the purpose, the technical scheme of the utility model is realized as follows:

a battery negative plate lithium pre-processing device comprises a lithium foil pre-processing unit, a rolling unit and a base film removing unit which are sequentially arranged; the lithium foil pretreatment unit comprises a base film storage mechanism, a lithium foil storage mechanism and at least one pair of composite rollers; the base film led out by the base film storage mechanism and the lithium foil led out by the lithium foil storage mechanism are pressed by the composite roller to form a pre-lithium composite layer; the rolling unit comprises a pole piece conveying mechanism and at least one pair of pressing rollers; the pre-lithium composite layer led out by the lithium foil pretreatment unit and the negative pole piece led in by the pole piece conveying mechanism are guided to be overlapped and are pressed by the pressing roller to form a film-containing pre-lithium pole piece; and the base film is arranged on the surface of the film-containing pre-lithium pole piece; the base film removing unit is used for removing the base film on the surface of the film-containing pre-lithium pole piece to form the pre-lithium pole piece.

Further, the base film peeling unit comprises a base film peeling roller driven to rotate, and the base film peeled from the film-containing pre-lithium pole piece is rolled by the base film peeling roller so as to peel the base film from the film-containing pre-lithium pole piece.

Furthermore, the battery negative plate pre-lithium device further comprises a baking unit for baking the pre-lithium plate.

Further, the lithium foil pretreatment unit and the base film uncovering unit are respectively arranged on two groups of the two sides of the negative plate; the two pre-lithium composite layers led out by the two lithium foil pretreatment units are respectively pressed on the surfaces of the two sides of the negative plate; the two base film removing units are respectively used for removing the base films on the two side surfaces of the film-containing pre-lithium electrode plate.

Further, the battery negative plate pre-lithium device is provided with a plurality of guide rollers for guiding the base film, the lithium foil, the negative plate, the pre-lithium plate or the film-containing pre-lithium plate.

Furthermore, the rolling unit adopts a roller press, and the pressing speed and force of the roller press are adjustable.

Further, a stripping mechanism is arranged in the lithium foil pretreatment unit; the stripping mechanism is positioned between the lithium foil storage mechanism and the composite roller, and the lithium foil led out from the lithium foil storage mechanism is pressed by the composite roller after passing through the stripping mechanism; the stripping mechanism is used for stripping the local area of the lithium foil.

Further, the stripping mechanism is provided with a plurality of stripping knives which are uniformly distributed at intervals along the width direction of the lithium foil; and along with the passing of the lithium foil, the stripping knives respectively strip a strip-shaped area on the lithium foil, so that the lithium foil pressed on the base film is in a plurality of strips uniformly distributed at intervals.

Further, the peeling mechanism also comprises a separation roller arranged at the downstream of the peeling knife; the stripped lithium foil is guided by the separation roller and discharged to the outside of the battery negative plate lithium pre-preparing device.

Furthermore, the peeling knife comprises two cutting edges which are arranged along the advancing direction of the lithium foil, and the distance between the two cutting edges is adjustable.

Compared with the prior art, the utility model has the following advantages:

according to the battery negative plate pre-lithium equipment, the lithium foil pretreatment unit, the rolling unit and the base film uncovering unit are sequentially arranged, so that the base film and the lithium foil can be pressed to form a pre-lithium composite layer, the pre-lithium composite layer is pressed to the surface of the negative plate through the rolling unit to form a film-containing pre-lithium plate, and the base film containing the film-containing pre-lithium plate is uncovered through the base film uncovering unit to form the pre-lithium plate, so that the negative plate can be well pre-lithium.

In addition, through the baking unit that sets up, be favorable to toasting lithium electrode piece in advance high temperature. The lithium foil processing units and the base film removing units are respectively arranged on two groups of the two sides of the negative plate, and the two sides of the negative plate can be simultaneously subjected to pre-lithiation processing.

In addition, the stripping mechanism for stripping the local area of the lithium foil can enable the local blank area to be formed on the lithium foil, so that when the lithium foil is pressed to the two sides of the negative plate, the uniformity of lithium ion diffusion distribution is facilitated, the negative electrode can be uniformly pre-lithiated, and the capacity, the energy density and the cycle life of the battery can be improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the utility model and, together with the description, serve to explain the utility model and not to limit the utility model. In the drawings:

fig. 1 is a schematic structural diagram of a battery negative plate embedding device according to an embodiment of the present invention;

FIG. 2 is an enlarged view of portion A of FIG. 1;

FIG. 3 is a schematic diagram of a stripping mechanism according to an embodiment of the present invention;

description of reference numerals:

1. a negative plate; 10. pre-lithium pole pieces; 11. pre-lithium composite layer; 110. a base film; 111. a lithium foil;

200. a base film storage roller; 210. a lithium foil stock roll; 22. a stripping mechanism; 220. stripping; 221. a separation roller; 222. a mounting seat; 23. a compound roller; 24. a guide roller; 300. a compression roller; 400. and (4) removing the roller from the base film.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it should be noted that, if terms indicating orientation or positional relationship such as "upper", "lower", "inside", "outside", etc. appear, they are based on the orientation or positional relationship shown in the drawings and are only for convenience of describing the present invention and simplifying the description, but do 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. Furthermore, the appearances of the terms first, second, etc. in this specification are not necessarily all referring to the same item, but are instead intended to cover the same item.

In addition, in the description of the present invention, the terms "mounted," "connected," and "connecting" are to be construed broadly unless otherwise specifically limited. For example, the connection can be fixed, detachable or integrated; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. To those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in conjunction with specific situations.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The embodiment relates to a device for pre-lithium of a battery negative electrode sheet 1, and in the overall structure, as shown in fig. 1, the device for pre-lithium of the battery negative electrode sheet 1 mainly comprises a lithium foil pretreatment unit, a rolling unit and a base film removing unit which are sequentially arranged. The lithium foil pretreatment unit comprises a base film storage mechanism, a lithium foil storage mechanism and at least one pair of composite rollers 23, wherein the base film 110 led out by the base film storage mechanism and the lithium foil 111 led out by the lithium foil storage mechanism are pressed by the composite rollers 23 to form a lithium composite layer 11. The rolling unit comprises a pole piece conveying mechanism and at least one pair of pressing rollers 300, a pre-lithium composite layer 11 led out by the lithium foil pretreatment unit and a negative pole piece 1 led in by the pole piece conveying mechanism are guided to be overlapped, and are pressed by the pressing rollers 300 to form a film-containing pre-lithium pole piece 10, and at the moment, the base film 110 is arranged on the surface of the film-containing pre-lithium pole piece. And the base film removing unit is used for removing the base film 110 on the surface of the pre-lithium electrode sheet containing the film to form the pre-lithium electrode sheet 10.

Wherein the base film stock mechanism includes a base film stock roller 200 and the lithium foil stock mechanism includes a lithium foil stock roller 210. Through the lithium foil pretreatment unit, the rolling unit and the base film uncovering unit which are sequentially arranged, the base film 110 and the lithium foil 111 can be pressed to form a pre-lithium composite layer 11, the pre-lithium composite layer 11 is pressed to the surface of the negative plate 1 through the rolling unit to form a pre-lithium plate containing film, and the base film uncovering unit is used for uncovering the base film 110 containing the pre-lithium plate containing film to form the pre-lithium plate 10, so that better pre-lithium can be carried out on the negative plate 1.

Specifically, as a preferred embodiment of this embodiment, in this embodiment, with reference to fig. 1, the lithium foil pre-processing units and the base film peeling units are respectively disposed in two groups on two sides of the negative electrode sheet 1, two pre-lithium composite layers 11 led out by the two lithium foil pre-processing units are respectively pressed on two side surfaces of the negative electrode sheet 1, and the two base film peeling units respectively form peeling of the base films 110 on two side surfaces of the pre-lithium electrode sheet.

In addition, the battery negative electrode sheet 1 pre-lithium device of the embodiment has a plurality of guide rollers 24 for guiding the base film 110, the lithium foil 111, the negative electrode sheet 1, the pre-lithium electrode sheet 10 and the pre-lithium electrode sheet containing a film, so that the base film 110, the lithium foil 111, the negative electrode sheet 1, the pre-lithium electrode sheet 10 and the pre-lithium electrode sheet containing a film can be smoothly conveyed, thereby ensuring the smooth pre-lithiation of the electrode sheets.

In this embodiment, the aforementioned rolling unit preferably adopts a roller press in the existing product, and the roller press includes a pole piece conveying mechanism and a pair of pressing rollers 300, wherein the pole piece conveying mechanism may adopt a structural form that a motor drives a pole piece conveying roller, for example. And a pair of compression rollers 300 is arranged at the downstream of the pole piece conveying mechanism, so that the conveying of the pre-lithium composite layers 11 positioned at the two sides of the negative pole piece 1 can be facilitated while the negative pole piece 1 is conveyed, and the two pre-lithium composite layers 11 and the negative pole piece 1 are pressed together to form the film-containing pre-lithium pole piece.

It should be noted that, the pole piece conveying mechanism adopts a roller press, which is also beneficial to adjusting the speed and force when the pre-lithium composite layer 11 and the negative pole piece 1 are pressed, so as to improve the pressing effect. Also, preferably, the pressure of the roll press in this embodiment is 25Kg, and the line speed is 6.8m/min, so that the lithium foil 111 is smoothly transferred to both sides of the negative electrode sheet 1 by the press roll 300.

As a further improvement of this embodiment, the lithium foil preprocessing unit of this embodiment is provided with a stripping mechanism 22, the stripping mechanism 22 is specifically located between the lithium foil storage mechanism and the composite roller 23, the lithium foil 111 led out from the lithium foil storage mechanism is pressed by the composite roller 23 after passing through the stripping mechanism 22, and the stripping mechanism 22 is used for stripping a local area of the lithium foil 111, so that a local blank area is formed on the lithium foil 111, and when the lithium foil 111 is pressed on two sides of the negative electrode sheet 1, uniformity of lithium ion diffusion distribution is facilitated, so that the negative electrode can be uniformly pre-lithiated.

Specifically, as shown in fig. 1 and 3, the peeling mechanism 22 specifically includes a mounting base 222 and a plurality of peeling knives 220 disposed on the mounting base 222 and spaced apart from each other in the width direction of the lithium foil 111, and each peeling knife 220 peels off a strip region of the lithium foil 111 as the lithium foil 111 passes through, so that the lithium foil 111 pressed on the base film 110 is spaced apart from each other and spaced apart from each other. The longitudinal direction of each strip is arranged along the traveling direction of the lithium foil 111.

In addition, the peeling mechanism 22 of the present embodiment further includes a separation roller 221 disposed downstream of the peeling blade 220, and the peeled lithium foil 111 is discharged to the outside of the lithium pre-charging device of the battery negative electrode sheet 1 through the guide of the separation roller 221. Therefore, the local part of the lithium foil 111 can be smoothly stripped, and the stripped lithium foil 111 can be smoothly discharged to a specified position, so that the subsequent lamination of the pre-lithium composite layer 11 and the negative electrode sheet 1 and the preparation of the pre-lithium electrode sheet 10 are facilitated.

With reference to fig. 1 and fig. 3, the stripping blade 220 of the present embodiment includes two blades disposed facing the traveling direction of the lithium foil 111, and the distance between the two blades is adjustable, so that the blank area on the lithium foil 111, that is, the distance between the long strips on the lithium foil 111 can be adjusted, thereby facilitating adjustment of the pre-lithium amount from the pre-lithium to the lithium foil 111 on the pole piece, and improving the pre-lithiation effect of the pole piece.

It is worth mentioning that the adjustment of the distance between the two blades can be realized by the existing mature technology, for example, the mounting seat 222 is provided with a long hole, each blade is screwed in each long hole correspondingly, and the adjustment of the distance between the two blades is realized by different positions in the long hole.

In this embodiment, the above-mentioned base film peeling unit includes a base film peeling roller 400 driven to rotate, and as shown in fig. 1 and fig. 2, the base film peeling rollers 400 are respectively disposed on two sides of the pre-lithium electrode sheet containing film, and the base film 110 peeled off from the pre-lithium electrode sheet containing film is rolled by the rotating base film peeling roller 400, so that the base film 110 on the pre-lithium electrode sheet containing film can be peeled off to form the pre-lithium electrode sheet 10.

In addition, the battery negative electrode sheet 1 pre-lithium device of the embodiment further comprises a baking unit for baking the pre-lithium electrode sheet, which is arranged at the downstream of the base film uncovering unit, so that the pre-lithium electrode sheet uncovered by the base film 110 can be baked at a high temperature. It should be noted that the baking unit preferably employs a vacuum oven, so as to have the characteristics of fast drying speed, less pollution, precise temperature control, high program control efficiency, stability and safety.

When the pre-lithium electrode sheet 10 of this embodiment is specifically manufactured, the base film 110 on the base film storage roller 200, the lithium foil 111 on the lithium foil storage roller 210, and the negative electrode sheet 1 on the negative electrode sheet storage roller can be manually conveyed to the compound roller 23, the pressing roller 300, and the base film removing roller 400, so that the automation of the subsequent manufacturing is facilitated. During the transportation of the lithium foil 111, the lithium foil 111 is partially peeled by the peeling knife 220, and the peeled lithium foil 111 and the base film 110 are rolled by the composite roller 23 to form the pre-lithium composite layer 11. At this time, the pre-lithium composite layers 11 on both sides and the negative electrode sheet 1 are rolled by the pressing roller 300 to form a film-containing pre-lithium electrode sheet, and the base film 110 on the surface of the film-containing pre-lithium electrode sheet is removed by the base film removing roller 400, so as to form the pre-lithium electrode sheet 10.

The battery negative plate 1 pre-lithium equipment of this embodiment can carry out pre-lithiation treatment to negative plate 1 through the lithium foil pretreatment unit, the rolling unit and the base film removing unit which are arranged in sequence, and the stripping mechanism 22 and the baking unit, and when laminating the lithium foil 111 to the two sides of the negative plate 1, the uniformity of lithium ion diffusion distribution is facilitated, so that the negative electrode can be uniformly pre-lithiated, and the battery capacity, the energy density and the cycle life can be improved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. The device for pre-lithium of the battery negative plate is characterized by comprising a lithium foil pretreatment unit, a rolling unit and a base film removing unit which are sequentially arranged;

the lithium foil pretreatment unit comprises a base film storage mechanism, a lithium foil storage mechanism and at least one pair of composite rollers (23); the base film (110) led out by the base film storing mechanism and the lithium foil (111) led out by the lithium foil storing mechanism are pressed together by the composite roller (23) to form a pre-lithium composite layer (11);

the rolling unit comprises a pole piece conveying mechanism and at least one pair of pressing rollers (300); the pre-lithium composite layer (11) led out by the lithium foil pretreatment unit and the negative pole piece (1) led in by the pole piece conveying mechanism are guided to be overlapped and are pressed by the pressing roller (300) to form a film-containing pre-lithium pole piece; and the number of the first and second electrodes,

the base film (110) is arranged on the surface of the film-containing pre-lithium pole piece;

the base film uncovering unit is used for uncovering the base film (110) on the surface of the film-containing pre-lithium pole piece to form the pre-lithium pole piece (10).

2. The battery negative plate pre-lithium device according to claim 1, characterized in that:

the base film peeling unit comprises a base film peeling roller (400) driven to rotate, and the base film (110) peeled off from the film-containing pre-lithium pole piece is rolled by the base film peeling roller (400) so as to peel off the base film (110) on the film-containing pre-lithium pole piece.

3. The battery negative plate pre-lithium device according to claim 1, characterized in that:

the battery negative plate pre-lithium device further comprises a baking unit for baking the pre-lithium plate (10).

4. The battery negative plate pre-lithium device according to claim 1, characterized in that:

the lithium foil pretreatment unit and the base film uncovering unit are respectively arranged on two groups of two sides of the negative plate (1);

the two pre-lithium composite layers (11) led out by the two lithium foil pretreatment units are respectively pressed on the two side surfaces of the negative plate (1);

the two base film removing units are respectively used for removing the base films (110) on the two side surfaces of the film-containing pre-lithium electrode plate.

5. The battery negative plate pre-lithium device according to claim 1, characterized in that:

the battery negative plate pre-lithium device is provided with a plurality of guide rollers (24) for guiding the base film (110), the lithium foil (111), the negative plate (1), the pre-lithium pole piece (10) or the film-containing pre-lithium pole piece.

6. The battery negative plate pre-lithium device according to claim 1, characterized in that:

the rolling unit adopts a roller press, and the pressing speed and force of the roller press are adjustable.

7. The battery negative plate pre-lithium device according to any one of claims 1 to 6, characterized in that:

a stripping mechanism (22) is arranged in the lithium foil pretreatment unit;

the stripping mechanism (22) is positioned between the lithium foil storage mechanism and the composite roller (23), and the lithium foil (111) led out from the lithium foil storage mechanism is pressed by the composite roller (23) after passing through the stripping mechanism (22);

the stripping mechanism (22) is used for stripping a local area of the lithium foil (111).

8. The battery negative plate pre-lithium device according to claim 7, characterized in that:

the peeling mechanism (22) is provided with a plurality of peeling knives (220) which are uniformly distributed at intervals along the width direction of the lithium foil (111);

with the passing of the lithium foil (111), the stripping knives (220) strip a strip-shaped region on the lithium foil (111) respectively, so that the lithium foil (111) pressed on the base film (110) is in a plurality of strips uniformly distributed at intervals.

9. The battery negative plate pre-lithium device according to claim 8, wherein:

the peeling mechanism (22) further comprises a separation roller (221) arranged downstream of the peeling knife (220);

the stripped lithium foil (111) is guided by the separation roller (221) and discharged to the outside of the battery negative plate pre-lithium device.

10. The battery negative plate pre-lithium device according to claim 8, wherein:

the peeling knife (220) comprises two cutting edges which are arranged opposite to the advancing direction of the lithium foil (111), and the distance between the two cutting edges is adjustable.