Laminated battery and manufacturing method thereof

Abstract

The invention relates to the technical field of batteries, in particular to a laminated battery and a manufacturing method thereof.The laminated battery comprises a positive plate and a negative plate which are arranged at an included angle, the positive plate and the negative plate are alternately folded in a reciprocating mode to form a columnar laminated structure, and each plate layer of the negative plate is provided with a negative tab connecting part integrally formed with the negative plate; each sheet layer of the positive plate is provided with a positive tab connecting part which is integrally formed with the positive plate, and each positive tab connecting part and each negative tab connecting part are positioned on the same side of the laminated structure. The positive tab connecting parts and the negative tab connecting parts are positioned on the same side of the lamination structure, and a non-energy storage structure protruding out of the lamination structure is only formed on one side of the lamination structure, so that the energy density of the lamination battery is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a laminated battery and a manufacturing method thereof. Background Art

[0002] Laminated batteries refer to automotive lithium batteries that use the lamination process. Laminated batteries have higher energy density, more stable internal structure, higher safety, more stable expansion force, smaller internal resistance and longer cycle life, and have been widely used.

[0003] At present, when a laminated battery is produced, the separated positive and negative electrodes need to be alternately stacked by a laminating machine, and the production efficiency is low. The Chinese invention patent with the publication number CN118136914A discloses a laminated battery and a laminated battery manufacturing method thereof, which is to place one of the positive electrode sheet and the negative electrode sheet vertically or obliquely on the other, and alternately fold the positive electrode sheet and the negative electrode sheet, so that each positive electrode active material unit on the positive electrode sheet and each negative electrode active material unit on the negative electrode sheet are alternately stacked to form a laminated structure, which reduces the requirements for the alignment and stacking process of each electrode sheet and improves the production efficiency of the laminated battery; however, each positive electrode ear connection part and each negative electrode ear connection part are respectively located on the adjacent two sides of the laminated structure, and the positive electrode ear connection part and the negative electrode ear connection part will increase the width of the adjacent two sides of the laminated structure respectively, and the positive electrode ear connection part and the negative electrode ear connection part cannot store energy, which will cause the non-energy storage structure of the laminated battery to occupy an increased space, thereby reducing the energy density of the laminated battery. Summary of the invention

[0004] The technical problem to be solved by the present invention is that in the current laminated battery, the positive electrode ear connection part and the negative electrode ear connection part are respectively located on both sides of the battery cell, forming a non-energy storage structure on both sides of the laminated structure, resulting in a low energy density of the laminated battery.

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a laminated battery, comprising a positive electrode sheet and a negative electrode sheet arranged at an angle, wherein the positive electrode sheet and the negative electrode sheet are folded back and forth alternately to form a laminated structure, and each layer of the negative electrode sheet has a negative electrode ear connection portion integrally formed with the negative electrode sheet; each layer of the positive electrode sheet has a positive electrode ear connection portion integrally formed with the positive electrode sheet, and each of the positive electrode ear connection portions and each of the negative electrode ear connection portions are located on the same side of the laminated structure.

[0006] As a preferred solution, each fold line of the positive electrode sheet located on the first side of the laminate structure is defined as a first fold line, and each fold line of the positive electrode sheet located on the second side of the laminate structure is defined as a second fold line;

[0007] The portion of each sheet layer of the positive electrode sheet close to each first fold line, or the portion of each sheet layer of the positive electrode sheet close to each second fold line protrudes to the outside of the laminated structure and forms each positive electrode tab connection portion, and each positive electrode tab connection portion has a notch;

[0008] Each of the negative electrode ear connecting parts is located in each of the notches.

[0009] As a preferred solution, each of the negative electrode ear connecting portions is arranged at a fold line of the negative electrode sheet close to the notch.

[0010] As a preferred embodiment, the positive electrode sheet comprises a first flexible base strip and a plurality of positive electrode active material units arranged on the first flexible base strip at intervals along the length direction of the first flexible base strip, and each fold line of the positive electrode sheet is located between two adjacent positive electrode active material units;

[0011] The negative electrode sheet comprises a second flexible base strip and a plurality of negative electrode active material units arranged on the second flexible base strip at intervals along the length direction of the second flexible base strip, and each fold line of the negative electrode sheet is located between two adjacent negative electrode active material units.

[0012] As a preferred solution, the surface of the negative electrode sheet and / or the positive electrode sheet is covered with an insulating film.

[0013] A method for manufacturing the above-mentioned laminated battery comprises the following steps:

[0014] Step S1, manufacturing a positive electrode sheet with a positive electrode tab connection portion and a negative electrode sheet with a negative electrode tab connection portion;

[0015] Step S2, placing one of the positive electrode sheet and the negative electrode sheet on the other at an angle, and adjusting the placement positions of the positive electrode sheet and the negative electrode sheet so that the directions of the positive electrode tab connection parts and the negative electrode tab connection parts are the same;

[0016] Step S3, folding the positive electrode sheet and the negative electrode sheet alternately and reciprocally, and stacking the positive electrode sheet and the negative electrode sheet into a laminate structure, so that each positive electrode tab connection portion and each negative electrode tab connection portion are located on the same side of the laminate structure.

[0017] As a preferred solution, step S1 includes:

[0018] Step S11, preparing a first flexible base strip and a second flexible base strip;

[0019] Step S12, processing a positive electrode active material unit and a negative electrode active material unit on the first flexible base strip and the second flexible base strip respectively;

[0020] Step S13, cutting the first flexible base strip into positive electrode sheets with positive electrode tab connecting portions; cutting the second flexible base strip into negative electrode sheets with negative electrode tab connecting portions.

[0021] As a preferred solution, in step S13, cutting the second flexible base strip into a negative electrode sheet with a negative electrode ear connecting portion comprises: cutting the edge of the second flexible base strip in the length direction, cutting a plurality of lugs arranged at intervals along the length direction of the second flexible base strip from the edge of the second flexible base strip, wherein every two negative electrode active material units have one lug, and each lug is located at the interval between two adjacent negative electrode active material units;

[0022] In the step S3, when folding the negative electrode sheet, each lug is folded in half at the middle part, and each lug is folded into two negative electrode lug connecting parts.

[0023] As a preferred embodiment, in step S12, the positive electrode active material units processed on the first flexible base strip have the following arrangement rule: two positive electrode active material units form a group of positive electrode units, a plurality of groups of positive electrode units are evenly spaced in the length direction of the first flexible base strip, and the first flexible base strip between two adjacent groups of positive electrode units is defined as a first connecting portion;

[0024] In the step S13, cutting the first flexible base strip into a positive electrode sheet with a positive electrode tab connection portion includes: cutting a notch in the first connection portion;

[0025] In the step S3, when folding the positive electrode sheet, the first connecting portion is folded in half at the middle of each first connecting portion, and each first connecting portion is folded into two positive electrode ear connecting portions;

[0026] When the negative electrode sheet is folded, each negative electrode ear connecting portion is located in each notch.

[0027] As a preferred solution, the first flexible base strip between two positive electrode units in the same group of positive electrode units is defined as a second connecting portion, and a width of the second connecting portion is smaller than a width of the first connecting portion.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The laminated battery of the present invention comprises a positive electrode sheet and a negative electrode sheet arranged at an angle, the positive electrode sheet and the negative electrode sheet are folded back and forth alternately to form a laminated structure, each sheet layer of the negative electrode sheet has a negative electrode ear connection portion integrally formed with the negative electrode sheet; each sheet layer of the positive electrode sheet has a positive electrode ear connection portion integrally formed with the positive electrode sheet, each positive electrode ear connection portion and each negative electrode ear connection portion are located on the same side of the laminated structure, and a non-energy storage structure protruding outside the laminated structure is formed only on one side of the laminated structure, thereby improving the energy density of the laminated battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of a laminated battery of the present invention;

[0031] Figure 2 A schematic diagram of the structure of the second flexible base strip after the negative electrode active material is processed;

[0032] Figure 3 It is a schematic diagram of the structure of the first flexible base strip after processing the positive electrode active material;

[0033] Figure 4 Schematic diagram of the structure of the negative electrode sheet;

[0034] Figure 5 It is a schematic diagram of the structure of the positive electrode;

[0035] Figure 6 A schematic diagram of the stacking method of the negative electrode sheet and the positive electrode sheet;

[0036] In the figure, 1. stacked structure, 2. negative electrode sheet, 21. negative electrode ear connection part, 22. lug, 3. positive electrode sheet, 31. positive electrode ear connection part, 32. first fold line, 33. second fold line, 34. notch, 4. positive electrode active material unit, 5. negative electrode active material unit, 6. first flexible base strip, 61. first connection part, 62. second connection part, 7. second flexible base strip. DETAILED DESCRIPTION

[0037] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0038] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, which are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the "first" information may also be referred to as the "second" information, and similarly, the "second" information may also be referred to as the "first" information.

[0039] like Figures 1 to 6As shown, the laminated battery of the present invention comprises a positive electrode sheet 3 and a negative electrode sheet 2 arranged at an angle, the positive electrode sheet 3 and the negative electrode sheet 2 are folded back and forth alternately to form a laminated structure 1, the laminated structure 1 is columnar, each sheet layer of the negative electrode sheet 2 has a negative electrode ear connection portion 21 integrally formed with the negative electrode sheet 2; each sheet layer of the positive electrode sheet 3 has a positive electrode ear connection portion 31 integrally formed with the positive electrode sheet 3, and each positive electrode ear connection portion 31 and each negative electrode ear connection portion 21 are located on the same side of the laminated structure 1. Since each positive electrode ear connection portion 31 and each negative electrode ear connection portion 21 are located on the same side of the laminated structure 1, a non-energy storage structure protruding from the laminated structure 1 is formed only on one side of the laminated structure 1, thereby improving the energy density of the laminated battery.

[0040] In this embodiment, the positive electrode sheet 3 and the negative electrode sheet 2 are arranged vertically, and each fold line of the positive electrode sheet 3 located on the first side of the laminate structure 1 is defined as a first fold line 32, and each fold line of the positive electrode sheet 3 located on the second side of the laminate structure 1 is defined as a second fold line 33; the portion of each sheet layer of the positive electrode sheet 3 close to each first fold line 32, or the portion of each sheet layer of the positive electrode sheet 3 close to each second fold line 33 protrudes to the outside of the laminate structure 1 and forms each positive electrode ear connection portion 31. To ensure that the positive electrode ear connection portion 31 and the negative electrode ear connection portion 21 are located on the same side of the laminate structure 1, at least one side of each positive electrode ear connection portion 31 has a gap with the outside of the positive electrode sheet 3, and the gap forms an accommodating space for accommodating the negative electrode ear connection portion 21, and each negative electrode ear connection portion 21 is respectively located in each gap.

[0041] In this embodiment, Figure 6 As shown, the positive electrode sheet 3 is arranged left to right in the length direction, and the negative electrode sheet 2 is arranged front to back in the length direction, the first fold line 32 is located on the left side of the laminate structure 1, and the second fold line 33 is located on the right side of the laminate structure 1, and the positive electrode ear connection portion 31 is arranged at the first fold line 32, and the positive electrode ear connection portion 31 protrudes to the left outside the left side of the positive electrode sheet 3, and the rear side of the positive electrode ear connection portion 31 has a notch 34, and the negative electrode ear connection portion 21 is arranged in the notch 34, and the negative electrode ear connection portion 21 and the positive electrode ear connection portion 31 are both located on the left side of the laminate structure 1. In other embodiments of the present invention, both the negative electrode ear connection portion 21 and the positive electrode ear connection portion 31 can be arranged on the right side of the laminate structure 1. In this case, the positive electrode ear connection portion 31 is arranged at the second fold line 33, and the negative electrode ear connection portion 21 is arranged on the right side of the negative electrode sheet 2. In other embodiments of the present invention, the arrangement of the positive electrode ear connection portion 31 and the negative electrode ear connection portion 21 can also be exchanged, and the negative electrode ear and the positive electrode ear connection portion 31 can be arranged on the front or rear side of the laminate structure 1.

[0042] In this embodiment, each negative electrode ear connection portion 21 is arranged at the fold line of the negative electrode sheet 2 near the notch 34. Specifically, in this embodiment, the fold line of the negative electrode sheet 2 includes a front fold line and a rear fold line, the rear fold line is close to the notch 34, the negative electrode ear connection portion 21 is arranged at the rear fold line, and the negative electrode ear connection portion 21 protrudes to the left outside the negative electrode sheet 2. In this embodiment, the negative electrode ear connection portions 21 of two adjacent sheet layers of the negative electrode sheet 2 are arranged in one piece; in other embodiments of the present invention, a negative electrode ear connection portion 21 can be separately arranged on each sheet layer of the negative electrode sheet 2.

[0043] In this embodiment, the positive electrode sheet 3 includes a first flexible base strip 6 and a plurality of positive electrode active material units 4 arranged on the first flexible base strip 6 at intervals along the length direction of the first flexible base strip 6. The positive electrode active material is a positive electrode paste, which is coated on the first flexible base strip 6. After the positive electrode paste is cured, it is stably connected to the first flexible base strip 6; each fold line of the positive electrode sheet 3 is located between two adjacent positive electrode active material units 4, thereby ensuring that the positive electrode sheet 3 is easy to bend and saving the amount of positive electrode paste. The negative electrode sheet 2 includes a second flexible base strip 7 and a plurality of negative electrode active material units 5 arranged on the second flexible base strip 7 at intervals along the length direction of the second flexible base strip 7. Each fold line of the negative electrode sheet 2 is located between two adjacent negative electrode active material units 5. The negative electrode active material is a negative electrode paste, which is coated on the second flexible base strip. Among them, the first flexible base strip 6 and the second flexible base strip 7 are both metal foils with good conductivity.

[0044] In this embodiment, in order to achieve insulation between the positive electrode sheet and the negative electrode sheet, the surface of the negative electrode sheet 2 and / or the positive electrode sheet 3 is covered with an insulating film. Specifically, the insulating film can be covered on both the front and back sides of the positive electrode sheet 3 in advance, or on both the front and back sides of the negative electrode sheet 2. When the insulating film is covered on the positive electrode sheet 3, it covers the area except the positive electrode tab connection portion 31; when the insulating film is covered on the negative electrode sheet 2, it covers the area except the negative electrode tab connection portion 21.

[0045] An embodiment of the method for manufacturing the laminated battery comprises the following steps:

[0046] Step S1, manufacturing a positive electrode sheet 3 and a negative electrode sheet 2;

[0047] Step S2, integrally forming a positive electrode tab connection portion 31 and a negative electrode tab connection portion 21 on the positive electrode sheet 3 and the negative electrode sheet 2;

[0048] Step S3, placing one of the positive electrode sheet 3 and the negative electrode sheet 2 on the other at an angle, and adjusting the placement positions of the positive electrode sheet 3 and the negative electrode sheet 2 so that the directions of the positive electrode tab connecting portions 31 and the negative electrode tab connecting portions 21 are the same;

[0049] Step S4, folding the positive electrode sheet 3 and the negative electrode sheet 2 alternately and reciprocally, and stacking the positive electrode sheet 3 and the negative electrode sheet 2 into a laminate structure 1, so that each positive electrode tab connection portion 31 and each negative electrode tab connection portion 21 are located on the same side of the laminate structure 1.

[0050] Wherein, step S1 comprises:

[0051] Step S11, preparing a first flexible base strip 6 and a second flexible base strip 7; the first flexible base strip 6 or the second flexible base strip 7 can be made of a roll or a cut sheet;

[0052] Step S12, processing the positive electrode active material unit 4 and the negative electrode active material unit 5 on the first flexible base strip 6 and the second flexible base strip 7, respectively. In this embodiment, the positive electrode active material unit 4 is processed on the surface of the first flexible base strip 6 by applying the positive electrode paste, and the negative electrode active material unit 5 is processed on the surface of the second flexible base strip 7 by applying the negative electrode paste. To ensure the compactness of the positive electrode active material unit 4 and the negative electrode active material unit 5, after the positive electrode paste is solidified, the positive electrode active material unit 4 and the negative electrode active material unit 5 are compacted by rolling.

[0053] Step S13 , cutting the first flexible base strip 6 into positive electrode sheets 3 with positive electrode tab connecting portions 31 ; and cutting the second flexible base strip 7 into negative electrode sheets 2 with negative electrode tab connecting portions 21 .

[0054] To facilitate the processing of the negative electrode ear connection portion 21, in step S13, cutting the second flexible base strip 7 into a negative electrode sheet 2 with a negative electrode ear connection portion 21 includes: cutting the edge of the second flexible base strip 7 in the longitudinal direction, cutting out a plurality of lugs 22 arranged at intervals along the longitudinal direction of the second flexible base strip 7 at the edge of the second flexible base strip 7, with one lug 22 for every two negative electrode active material units 5, and each lug 22 is located at the interval between two adjacent negative electrode active material units 5; in step S3, when folding the negative electrode sheet 2, folding it in half at the middle of each lug 22, and folding each lug 22 into two negative electrode ear connections 21.

[0055] To facilitate the processing of the positive electrode ear connection portion 31, in step S12, the positive electrode active material units 4 processed on the first flexible base strip 6 have the following arrangement rule: two positive electrode active material units 4 are used as a group of positive electrode units, multiple groups of positive electrode units are evenly spaced in the length direction of the first flexible base strip 6, and the first flexible base strip 6 between two adjacent groups of positive electrode units is defined as the first connection portion 61;

[0056] In step S13, cutting the first flexible base strip 6 into the positive electrode sheet 3 with the positive electrode tab connection portion 31 includes: cutting a notch 34 in the first connection portion 61;

[0057] In step S3, when folding the positive electrode sheet 3, each first connecting portion 61 is folded in half at the middle thereof, and each first connecting portion 61 is folded into two positive electrode tab connecting portions 31;

[0058] When the negative electrode sheet 2 is folded in step S3, each negative electrode tab connection portion 21 is located in each notch 34. In this embodiment, the notch 34 is arranged at the rear end of the positive electrode tab connection portion 31, so that the negative electrode tab connection portion 21 can be just arranged at the fold line of the negative electrode sheet 2, and the negative electrode tab connection portion 21 and the positive electrode tab connection portion 31 will not interfere with each other during the folding process of the negative electrode sheet 2 and the positive electrode sheet 3.

[0059] In other embodiments of the present invention, the notch 34 can be set in the middle of the first fold line 32, and the negative electrode ear connection part 21 can be set in the middle of each sheet layer of the negative electrode sheet 2. When the positive electrode sheet 3 and the negative electrode sheet 2 are folded, the negative electrode ear connection part 21 is inserted into each notch 34.

[0060] In this embodiment, the first flexible base strip 6 between two positive electrode units in the same group of positive electrode units is defined as the second connecting portion 62, and the width of the second connecting portion 62 is smaller than the width of the first connecting portion 61, further reducing the occupied area of ​​the non-energy storage unit.

[0061] In this embodiment, the width of the first flexible base band is the width of two positive electrode sheets 3, and the first flexible base band is cut into two positive electrode sheets 3 while the positive electrode ear connecting portion 31 is cut out; the width of the second flexible base band is the width of two negative electrode sheets 2, and the second flexible base band is cut into two negative electrode sheets 2 while the negative electrode ear connecting portion 21 is cut out, thereby improving the processing efficiency of the negative electrode sheets 2 and the positive electrode sheets 3.

[0062] Before step S2 , an insulating film is attached to the surface of the positive electrode sheet 3 and / or the negative electrode sheet 2 .

[0063] In summary, the laminated battery of the present invention comprises a positive electrode sheet 3 and a negative electrode sheet 2 arranged at an angle, the positive electrode sheet 3 and the negative electrode sheet 2 are folded back and forth alternately into a columnar laminated structure 1, and each layer of the negative electrode sheet 2 has a negative electrode ear connection portion 21 integrally formed with the negative electrode sheet 2; each layer of the positive electrode sheet 3 has a positive electrode ear connection portion 31 integrally formed with the positive electrode sheet 3, and each positive electrode ear connection portion 31 and each negative electrode ear connection portion 21 are located on the same side of the laminated structure 1, and only a non-energy storage structure protruding from the laminated structure 1 is formed on one side of the laminated structure 1, thereby improving the energy density of the laminated battery; moreover, the laminated battery manufacturing method of the present invention can efficiently process the above-mentioned laminated battery.

[0064] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A laminated battery, characterized in that: The invention comprises a positive electrode sheet (3) and a negative electrode sheet (2) arranged at an angle, wherein the positive electrode sheet (3) and the negative electrode sheet (2) are folded back and forth alternately to form a laminate structure (1), and each sheet layer of the negative electrode sheet (2) has a negative electrode ear connection portion (21) integrally formed with the negative electrode sheet (2); each sheet layer of the positive electrode sheet (3) has a positive electrode ear connection portion (31) integrally formed with the positive electrode sheet (3), and each positive electrode ear connection portion (31) and each negative electrode ear connection portion (21) are located on the same side of the laminate structure (1).

2. The laminated battery according to claim 1, characterized in that: defining each fold line of the positive electrode sheet (3) located on a first side of the laminate structure (1) as a first fold line (32), and each fold line of the positive electrode sheet (3) located on a second side of the laminate structure (1) as a second fold line (33); A portion of each sheet layer of the positive electrode sheet (3) close to each first fold line (32), or a portion of each sheet layer of the positive electrode sheet (3) close to each second fold line (33) protrudes to the outside of the laminated structure (1) and forms each positive electrode ear connecting portion (31), and each positive electrode ear connecting portion (31) has a notch (34); Each of the negative electrode tab connecting portions (21) is located in each of the notches (34).

3. The laminated battery according to claim 2, characterized in that: Each of the negative electrode tab connecting portions (21) is arranged at a fold line of the negative electrode sheet (2) close to the notch (34).

4. The laminated battery according to claim 1, characterized in that: The positive electrode sheet (3) comprises a first flexible base strip (6) and a plurality of positive electrode active material units (4) arranged on the first flexible base strip (6) at intervals along the length direction of the first flexible base strip (6), and each fold line of the positive electrode sheet (3) is located between two adjacent positive electrode active material units (4); The negative electrode sheet (2) comprises a second flexible base strip (7) and a plurality of negative electrode active material units (5) arranged on the second flexible base strip (7) at intervals along the length direction of the second flexible base strip (7), and each fold line of the negative electrode sheet (2) is located between two adjacent negative electrode active material units (5).

5. The laminated battery according to claim 1, characterized in that: The surface of the negative electrode sheet (2) and / or the positive electrode sheet (3) is covered with an insulating film.

6. A method for manufacturing a laminated battery according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step S1, manufacturing a positive electrode sheet (3) with a positive electrode tab connection portion (31) and a negative electrode sheet (2) with a negative electrode tab connection portion (21); Step S2, placing one of the positive electrode sheet (3) and the negative electrode sheet (2) on the other at an angle, and adjusting the placement positions of the positive electrode sheet (3) and the negative electrode sheet (2) so that the orientations of the positive electrode tab connecting portions (31) and the negative electrode tab connecting portions (21) are the same; Step S3, folding the positive electrode sheet (3) and the negative electrode sheet (2) alternately and reciprocally, and stacking the positive electrode sheet (3) and the negative electrode sheet (2) into a laminated structure (1), so that each positive electrode tab connection portion (31) and each negative electrode tab connection portion (21) are located on the same side of the laminated structure (1).

7. The method for manufacturing a laminated battery according to claim 6, characterized in that: The step S1 comprises: Step S11, preparing a first flexible base strip (6) and a second flexible base strip (7); Step S12, processing the positive electrode active material unit (4) and the negative electrode active material unit (5) on the first flexible base strip (6) and the second flexible base strip (7) respectively; Step S13, cutting the first flexible base strip (6) into positive electrode sheets (3) with positive electrode tab connecting portions (31); and cutting the second flexible base strip (7) into negative electrode sheets (2) with negative electrode tab connecting portions (21).

8. The method for manufacturing a laminated battery according to claim 7, characterized in that: In the step S13, cutting the second flexible base strip (7) into a negative electrode sheet (2) with a negative electrode ear connection portion (21) comprises: cutting the edge of the second flexible base strip (7) in the longitudinal direction, cutting out a plurality of lugs (22) arranged at intervals along the longitudinal direction of the second flexible base strip (7) from the edge of the second flexible base strip (7), wherein every two negative electrode active material units (5) have one lug (22), and each lug (22) is located at the interval between two adjacent negative electrode active material units (5); In the step S3, when folding the negative electrode sheet (2), each lug (22) is folded in half at the middle part, so that each lug (22) is folded into two negative electrode lug connecting parts (21).

9. The method for manufacturing a laminated battery according to claim 7, characterized in that: In the step S12, the positive electrode active material units (4) processed on the first flexible base strip (6) have the following arrangement rule: two positive electrode active material units (4) form a group of positive electrode units, a plurality of groups of positive electrode units are evenly spaced in the length direction of the first flexible base strip (6), and the first flexible base strip (6) between two adjacent groups of positive electrode units is defined as a first connecting portion (61); In the step S13, cutting the first flexible base strip (6) into a positive electrode sheet (3) with a positive electrode tab connecting portion (31) comprises: cutting a notch (34) in the first connecting portion (61); In the step S3, when folding the positive electrode sheet (3), each of the first connecting portions (61) is folded in half at the middle thereof, and each of the first connecting portions (61) is folded into two positive electrode tab connecting portions (31); When the negative electrode sheet (2) is folded, each of the negative electrode ear connecting portions (21) is located in each of the notches (34).

10. The method for manufacturing a laminated battery according to claim 9, characterized in that: The first flexible base strip (6) between two positive electrode units in the same group of positive electrode units is defined as a second connecting portion (62), and the width of the second connecting portion (62) is smaller than the width of the first connecting portion (61).

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