CN114937804A - Lamination method, battery cell and battery - Google Patents

Abstract

The invention provides a lamination method, a battery core and a battery, wherein the lamination method comprises the following steps: step A1: unreeling the negative material belt and the diaphragm material belt and carrying out thermal compounding to obtain a first compound material belt; step A2: cutting the first composite material belt to obtain a plurality of first composite units; step A3: and sequentially overlapping the plurality of first composite units and the plurality of positive plates. When the lamination is carried out, the negative material belt and the diaphragm material belt are firstly unreeled and thermally compounded to form a first compound material belt. After the first composite material belt is cut, the widths of the negative plate and the diaphragm are the same, so that when lamination is carried out, only the alignment degree of the first composite unit and the positive plate needs to be ensured, and the precision control difficulty is reduced. Meanwhile, the process does not need to cut the cathode material belt and the diaphragm material belt independently, so that the production process is simplified.

Description

Lamination method, battery cell and battery

Technical Field

The invention relates to the technical field of battery manufacturing processes, in particular to a lamination method, a battery core and a battery.

Background

Lamination is one of the processes of battery production, in which a positive electrode sheet, a separator and a negative electrode sheet are sequentially stacked and a cell is formed after hot pressing. In the prior art, in order to prevent the edge contact short circuit of the positive electrode sheet and the negative electrode sheet, the dimensional relationship of the positive electrode sheet, the separator and the negative electrode sheet is generally set as follows: the diaphragm is the largest and has the function of separating the positive plate from the negative plate; the area of the negative plate is smaller than that of the diaphragm; the area of the positive plate is smaller than that of the negative plate.

In the structure, the sizes of the positive plate, the diaphragm and the negative plate are different, so that the three plates need to be cut separately, and the process steps are complicated. Meanwhile, when lamination is carried out, the alignment degree of four materials (diaphragm-negative plate-diaphragm-positive plate) with three sizes needs to be ensured, so that the requirement on processing precision is high, and the equipment cost is high.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the defects of complex process and high precision requirement in the battery lamination process in the prior art, so that a lamination method, a battery core and a battery are provided.

In order to solve the above problems, the present invention provides a lamination method comprising: step A1: unreeling the negative material belt and the diaphragm material belt and carrying out thermal compounding to obtain a first compound material belt; step A2: cutting the first composite material belt to obtain a plurality of first composite units; step A3: and sequentially overlapping the plurality of first composite units and the plurality of positive plates.

Alternatively, in step a2, the first composite unit negative electrode sheet, and the two separators, the negative electrode sheet and the separators being the same width.

Optionally, step a3 includes: step A31: and the positive electrode material belt is subjected to die cutting or roll cutting to obtain a plurality of positive electrode plates.

Optionally, the lamination method further comprises: step A4: and thermally compounding the plurality of first compounding units and the positive electrode sheet which are sequentially stacked.

The invention also provides a lamination method, which comprises the following steps: step B1: unreeling the negative material belt and the diaphragm material belt and carrying out thermal compounding to obtain a first compound material belt; step B2: cutting the positive electrode material belt to obtain a plurality of positive electrode plates; step B3: carrying out thermal compounding on the first composite material belt and the plurality of positive plates to obtain a second composite material belt; step B4: cutting the second composite material belt to obtain a plurality of second composite units; step B5: and stacking a plurality of second composite units.

Alternatively, in step B4, the second composite unit comprises a negative electrode sheet, a positive electrode sheet and a separator, and the widths of the negative electrode sheet and the separator are the same.

Optionally, the second composite unit comprises a negative plate, a positive plate and two layers of diaphragms, and the two layers of diaphragms are respectively positioned at two sides of the negative plate.

Optionally, step B2 includes: step B21: and the positive electrode material belt is subjected to die cutting or roll cutting to obtain a plurality of positive electrode plates.

Optionally, step B4 includes: step B41: and die cutting or roll cutting the second composite material belt to obtain a plurality of second composite units.

Optionally, the lamination method further comprises: step B6: and thermally compounding a plurality of second compounding units which are sequentially superposed.

The invention also provides a battery cell, and the battery cell is manufactured by the lamination method.

The invention also provides a battery, which comprises the battery cell.

The invention has the following advantages:

by utilizing the technical scheme of the invention, the cathode material belt and the diaphragm material belt are firstly unreeled and thermally compounded during lamination, and the first compound material belt is formed after thermal compounding. After the first composite material belt is cut, the widths of the negative plate and the diaphragm are the same, so that when lamination is carried out, only the alignment degree of the first composite unit and the positive plate needs to be ensured, and the precision control difficulty is reduced. Meanwhile, the process does not need to separately cut the cathode material belt and the diaphragm material belt, so that the production process is simplified. Therefore, the technical scheme of the invention overcomes the defects of complex process and high precision requirement in the battery lamination process in the prior art.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 shows a schematic flow diagram of a first embodiment of the lamination method of the present invention;

fig. 2 shows a schematic diagram of a cell manufactured by the lamination method of fig. 1;

fig. 3 shows a schematic front view of the cell of fig. 1;

FIG. 4 shows a schematic view of the lamination process of FIG. 1;

FIG. 5 shows a schematic flow chart of a second embodiment of the lamination method of the present invention;

fig. 6 shows a schematic view of a cell manufactured by the lamination method of fig. 5; and

FIG. 7 shows a schematic view of the lamination process of FIG. 5;

description of reference numerals:

100. a negative electrode material belt; 101. a negative plate; 200. a membrane tape; 201. a diaphragm; 300. a positive electrode material belt; 301. a positive plate; 400. an electric core; 1000. a first composite tape; 1001. a first compound unit; 2000. a second composite tape; 2001. a second recombination unit.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it is to be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example one

As shown in fig. 1 to 4, the lamination method according to the first embodiment includes:

step A1: unreeling the negative material belt 100 and the diaphragm material belt 200 and carrying out thermal compounding to obtain a first compound material belt 1000;

step A2: cutting the first composite tape 1000 to obtain a plurality of first composite units 1001; step A3: the plurality of first lamination units 1001 are sequentially stacked with the plurality of positive electrode sheets 301.

By using the technical scheme of this embodiment, the negative electrode material tape 100 and the separator material tape 200 are firstly unreeled and thermally compounded during lamination, and a first composite material tape 1000 is formed after thermal compounding. After the first composite material tape 1000 is cut, the widths of the negative electrode sheet 101 and the separator 201 are the same, so that when lamination is performed, only the alignment degree of the first composite unit 1001 and the positive electrode sheet 301 needs to be ensured, and therefore the difficulty in precision control is reduced. Meanwhile, the process does not need to separately cut the negative material belt 100 and the diaphragm material belt 200, so that the production process is simplified. Therefore, the technical scheme of the embodiment overcomes the defects of complex lamination process and high precision requirement in the battery lamination process in the prior art.

As can be seen from fig. 4, in step a1, two separator tapes 200 and one negative electrode tape 100 need to be unwound, where the two separator tapes 200 are respectively located at two sides of the negative electrode tape 100, so that the first composite tape 1000 forms a three-layer structure including two separator tapes 200 and the negative electrode tape 100 located between the separator tapes 200.

After being unreeled, the two separator material belts 200 and the one cathode material belt 100 enter a hot press roller to be thermally combined to form a first composite material belt 1000.

As shown in fig. 2 to 4, in the technical solution of the present embodiment, in step a2, the first composite unit 1001 includes the negative electrode sheet 101 and two layers of the separator 201, and the widths of the negative electrode sheet 101 and the separator 201 are the same. Specifically, in step a2, after two separator tapes 200 and one anode tape 100 are thermally compounded and formed into a first composite unit 1001, the first composite unit 1001 continues to be transported in a circulating manner, and a cutter cuts continuously in the width direction of the first composite unit 1001, thereby forming a plurality of block-shaped first composite units 1001.

As will be understood by those skilled in the art, after cutting, the negative electrode material tape 100 is divided into a plurality of negative electrode sheets 101, and the separator material tape 200 is divided into a plurality of separators 201. Thus, in each first composite unit 1001, two separators 201 and one negative electrode tab 101 are included.

As can be seen from fig. 3, the widths of the negative electrode tab 101 and the separator 201 are the same and are larger than the width of the positive electrode tab 301 to be laminated later. Therefore, the separator 201 can cover the positive electrode tab 301, and prevent the edges of the negative electrode tab 101 and the positive electrode tab 301 from contacting to cause short circuit.

Since the adjacent negative electrode tabs 101 are equipotential, even if the edges of the negative electrode tabs 101 come into contact, a short circuit does not occur.

As shown in fig. 1 and 4, step a3 includes: step A31: the positive electrode material tape 300 is die-cut or roll-cut to obtain a plurality of positive electrode sheets 301. Specifically, in step a3, the positive electrode material tape 300 needs to be unwound, and the unwound positive electrode material tape 300 is divided into a plurality of positive electrode sheets 301 by means of hardware die cutting or roll cutting.

As can be seen from fig. 3, the width and area of the positive electrode sheet 301 are slightly smaller than those of the negative electrode sheet 101 and the separator 201.

As can be seen in fig. 4, in the lamination apparatus, a lamination station is provided in the middle, and the processing devices of the first lamination unit 1001 and the processing devices of the positive electrode sheets 301 are located on both sides of the lamination station.

The processing device of the first compound unit 1001 includes three unwinding rotating shafts, a pair of first hot press rolls, a first cutter and a first clamping jaw assembly. Wherein, the first cutter is used for cutting off the first composite tape 1000, and the first clamping jaw assembly is used for pulling the first composite tape 1000, and placing a first composite unit 1001 at the stacking table.

The processing device of the positive plate 301 comprises an unreeling rotating shaft, a second cutter and a second clamping jaw assembly. The second cutter is used for cutting off the positive electrode material strap 300, and the second clamping jaw assembly is used for pulling the positive electrode material strap 300 and placing one positive electrode plate 301 at the stacking table.

Therefore, the first composite unit 1001 and the positive electrode tab 301 may be alternately placed on the lamination station by the first jaw assembly and the second jaw assembly, thereby forming a lamination structure as shown in fig. 2.

As shown in fig. 1, in the technical solution of this embodiment, the lamination method further includes:

step A4: the plurality of first composite units 1001 and the positive electrode sheets 301 stacked in this order are hot-pressed.

Specifically, after the first composite unit 1001 and the positive electrode sheet 301 are alternately stacked, hot pressing is performed through a hot pressing process, so that the first composite unit 1001 and the positive electrode sheet 301 form a cell.

Example two:

as shown in fig. 5 to 7, the lamination method of the second embodiment includes:

step B1: unreeling the negative material belt 100 and the diaphragm material belt 200 and carrying out thermal compounding to obtain a first compound material belt 1000;

step B2: cutting the positive electrode material belt 300 to obtain a plurality of positive electrode sheets 301;

step B3: thermally compounding the first composite material belt 1000 and the plurality of positive plates 301 to obtain a second composite material belt 2000;

step B4: cutting the second composite tape 2000 to obtain a plurality of second composite units 2001;

step B5: a plurality of second composite units 2001 are stacked.

The main difference between the second embodiment and the first embodiment is that after the first composite tape 1000 is obtained, the plurality of positive electrode sheets 301 are first laminated with the first composite tape 1000 at intervals, so as to obtain a second composite tape 2000. The second composite strip 2000 is then cut to obtain a plurality of second composite units 2001. Finally, the plurality of second composite tape 2000 are stacked in sequence to form a laminate.

With reference to fig. 2 and 6, it can be understood by those skilled in the art that the lamination method of the first embodiment and the second embodiment has substantially the same structure, except for different process sequences. As can also be seen from fig. 2 and 6, in fact, a part of the second composite unit 2001 (i.e., two layers of the separators 201 and one layer of the negative electrode sheet 101) is the first composite unit 1001.

Further, in the present embodiment, the widths of the negative electrode tab 101 and the separator 201 are the same, and the width and area of the positive electrode tab 301 are smaller than those of the negative electrode tab 101, that is, in accordance with the structure of one of the embodiments.

As shown in fig. 6 and 7, in the technical solution of the present embodiment, the second composite unit 2001 includes a negative electrode tab 101, a positive electrode tab 301, and two layers of separators 201, and the two layers of separators 201 are respectively located on both sides of the negative electrode tab 101.

Specifically, referring to fig. 7, in processing the second composite unit 2001, two separator material tapes 200 and one cathode material tape 100 are unwound, and then the two separator material tapes are combined by a hot press roller to obtain the first composite material tape 1000. The positive electrode material tape 300 is unreeled and then cut, thereby forming a plurality of positive electrode sheets 301. The plurality of positive electrode plates 301 are positioned by air floatation alignment on the conveying belt, so that the intervals among the plurality of positive electrode plates 301 are the same. The first composite tape 1000 and the plurality of positive electrode sheets 301 are then thermally composited to form a second composite tape 2000. Finally, the second composite strip 2000 is divided into a plurality of second composite units 2001 by cutting.

Each second composite element 2001 is of the form: the separator 201-the negative electrode sheet 101-the separator 201-the positive electrode sheet 301.

As shown in fig. 5 to 7, in the technical solution of the present embodiment, step B2 includes:

step B21: the positive electrode material tape 300 is die-cut or roll-cut to obtain a plurality of positive electrode sheets 301.

Preferably, the positive electrode material tape 300 in this embodiment is die-cut to obtain a plurality of positive electrode sheets.

As shown in fig. 5 to fig. 7, in the technical solution of the present embodiment, step B4 includes:

step B41: the second composite strip 2000 is die cut or roll cut to provide a plurality of second composite units 2001.

Preferably, the second composite strip 2000 is roll cut to obtain a plurality of second composite units 2001.

As shown in fig. 5 to 7, in the solution of the present embodiment, the lamination method further includes:

step B6: the plurality of second composite units 2001 sequentially stacked are thermally pressed.

Specifically, after obtaining the plurality of second composite units 2001, the plurality of second composite units 2001 are sequentially stacked, and the stacked plurality of second composite units 2001 are hot-pressed by a hot-pressing apparatus, thereby obtaining a battery core.

The present example also provides a battery cell that is fabricated by the lamination method of the first embodiment, or a battery cell that is fabricated by the lamination method of the second embodiment.

The embodiment also provides a battery, which includes the battery cell 400, where the battery cell 400 is the battery cell described above.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims (12)

1. A method of laminating, comprising:

step A1: unreeling the negative material belt (100) and the diaphragm material belt (200) and carrying out thermal compounding to obtain a first compound material belt (1000);

step A2: cutting the first composite strip (1000) to obtain a plurality of first composite units (1001);

step A3: a plurality of positive electrode sheets (301) are sequentially stacked on a plurality of first composite units (1001).

2. A lamination method according to claim 1, wherein in step a2, said first composite unit (1001) comprises a negative electrode sheet (101) and two layers of separator (201), said negative electrode sheet (101) and said separator (201) having the same width.

3. The lamination process according to claim 1 or 2, characterized in that said step a3 comprises:

step A31: and the positive electrode material belt (300) is subjected to die cutting or roll cutting to obtain a plurality of positive electrode sheets (301).

4. The lamination method according to claim 1 or 2, further comprising:

step A4: and hot-pressing the plurality of first composite units (1001) and the positive electrode sheets (301) stacked in sequence.

5. A method of laminating, comprising:

step B1: unreeling the negative material belt (100) and the diaphragm material belt (200) and carrying out thermal compounding to obtain a first compound material belt (1000);

step B2: cutting the positive electrode material belt (300) to obtain a plurality of positive electrode sheets (301);

step B3: thermally compounding the first composite material belt (1000) and the plurality of positive plates (301) to obtain a second composite material belt (2000);

step B4: -cutting said second composite strip (2000) and obtaining a plurality of second composite units (2001);

step B5: -stacking a plurality of said second composite units (2001).

6. A lamination method according to claim 5, wherein, in said step B4, said second composite unit (2001) comprises a negative electrode sheet (101), a positive electrode sheet (301) and a separator (201), said negative electrode sheet and said separator having the same width.

7. A lamination method according to claim 5 or 6, wherein said second composite unit (2001) comprises a negative plate (101), a positive plate (301) and two layers of separator (201), two layers of said separator (202) being respectively located on both sides of said negative plate (101).

8. The lamination method according to claim 5 or 6, wherein said step B2 comprises:

step B21: the positive electrode material belt (300) is subjected to die cutting or roll cutting to obtain a plurality of positive electrode sheets (301).

9. The lamination method according to claim 5 or 6, wherein said step B4 comprises:

step B41: the second composite strip (2000) is die-cut or roll-cut to obtain a plurality of second composite units (2001).

10. The lamination method according to claim 5 or 6, further comprising:

step B6: hot-pressing a plurality of said second composite units (2001) stacked one on top of the other.

11. A cell, characterized in that it is manufactured by the lamination process according to any one of claims 1 to 4 or in that it is manufactured by the lamination process according to any one of claims 1 to 5.

12. A battery, characterized by comprising a cell (400), wherein the cell (400) is the cell of claim 11.

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