阅读说明：本技术 一种避免电芯叠片叠反的生产工艺 (Production process for preventing cell lamination from being overlapped ) 是由 曹礼 周玲 李雄成 于 2021-09-30 设计创作，主要内容包括：本发明公开一种避免电芯叠片叠反的生产工艺,该生产工艺包括以下步骤：步骤1)、将正极片和负极片分别进行一次裁切得到具有正极焊接留白区的正极片和负极焊接留白区的负极片；其中,使正极焊接留白区和负极焊接留白区的尺寸不同；步骤2)、将一次裁切后的正极片和负极片分别进行叠片,确认叠片是否存在异常,若无异常,将正极焊接留白区和负极焊接留白区再次进行二次裁切,并使正极焊接留白区和负极焊接留白区的尺寸相同,再进行极耳焊接。本发明可直观的将叠片叠反电芯挑出,避免不良品流出,避免发生电芯燃烧现象,提升产品安全系数。(The invention discloses a production process for avoiding cell lamination from being overlapped, which comprises the following steps: step 1), respectively cutting the positive plate and the negative plate for one time to obtain the positive plate with a positive electrode welding blank area and the negative plate with a negative electrode welding blank area; wherein, the sizes of the anode welding blank area and the cathode welding blank area are different; and 2) respectively laminating the positive plate and the negative plate which are cut once, determining whether the lamination is abnormal, if not, cutting the positive welding blank area and the negative welding blank area for the second time again, enabling the sizes of the positive welding blank area and the negative welding blank area to be the same, and then welding a tab. The invention can visually pick out the lamination reverse battery cell, avoid the outflow of defective products, avoid the phenomenon of battery cell combustion and improve the product safety coefficient.)

1. The production process for avoiding the cell lamination from being overlapped is characterized by comprising the following steps of:

step 1), respectively cutting the positive plate and the negative plate for one time to obtain the positive plate with a positive electrode welding blank area and the negative plate with a negative electrode welding blank area; wherein, the sizes of the anode welding blank area and the cathode welding blank area are different;

and 2) respectively laminating the positive plate and the negative plate which are cut once, determining whether the lamination is abnormal, if not, cutting the positive welding blank area and the negative welding blank area for the second time again, enabling the sizes of the positive welding blank area and the negative welding blank area to be the same, and then welding a tab.

2. The production process for avoiding cell lamination stacking according to claim 1, wherein: in the step 1), making the sizes of the anode welding blank area and the cathode welding blank area different comprises:

the width W1 of the anode welding blank area is larger than the width W2 of the cathode welding blank area, and the height H1 of the anode welding blank area is smaller than the height H2 of the cathode welding blank area; or

The width W1 of the welding blank area of the positive electrode is less than the width W2 of the welding blank area of the negative electrode, and the height H1 of the welding blank area of the positive electrode is greater than the height H2 of the welding blank area of the negative electrode.

3. The production process for avoiding cell lamination stacking according to claim 1, wherein: in step 2), the method for confirming whether the lamination has the abnormality comprises the following steps:

and during lamination, if the size of at least one pole piece is different from the sizes of other laminations, determining that the lamination is abnormal, otherwise, determining that no abnormality exists.

4. The production process for avoiding cell lamination stacking according to claim 3, wherein: the finding that at least one pole piece has a size different from the other lamination sizes includes:

the cathode plate is mistakenly stacked on the cathode plate, and due to the size difference of the cathode plate and the anode plate, a producer can find the abnormally stacked cathode plate immediately by visual observation; or

The negative plate is mistakenly stacked on the positive plate, and due to the size difference of the negative plate and the positive plate, a producer can immediately find the abnormally stacked negative plate by visual inspection.

5. The production process for avoiding cell lamination stacking according to claim 1, wherein: in the step 2), if the lamination is determined to be abnormal, picking out the abnormal pole piece and re-laminating.

6. The production process for avoiding cell lamination stacking according to claim 2, wherein:

the width W1 of the tab is less than or equal to that of the positive electrode welding blank area is less than or equal to 1/2 of the pole piece width; and/or

The width W2 of the tab is less than or equal to that of the negative electrode welding blank area is less than or equal to 1/2 of the pole piece width.

7. The production process for avoiding cell lamination stacking according to claim 2 or 6, wherein:

the height H1 of the welding blank area of the positive electrode is more than or equal to 5mm and less than or equal to 30 mm; and/or

The height H2 of the welding blank area of the negative electrode is less than or equal to 5mm and less than or equal to 30 mm.

8. The production process for avoiding cell lamination stacking according to claim 2, wherein: the width W1 of the positive electrode welding blank area is more than or equal to 5mm, and the width W2 of the negative electrode welding blank area is more than or equal to 10 mm.

9. The production process for avoiding cell lamination stacking according to claim 2 or 8, wherein: the height H1 of the positive electrode welding blank area is more than or equal to 5mm, and the height H2 of the negative electrode welding blank area is more than or equal to 10 mm.

10. The production process for avoiding cell lamination stacking according to claim 1, wherein: in the step 2), after secondary cutting, the width of the anode welding blank area and the width of the cathode welding blank area are 10-80 mm; the height of the anode welding blank area and the height of the cathode welding blank area are 5-15 mm.

Technical Field

The invention belongs to the technical field of battery cells, and particularly relates to a production process for preventing battery cell lamination from being overlapped.

Background

Nowadays, with the progress and development of society and science and technology, green and high-efficiency secondary batteries are vigorously developed in various countries. As a novel secondary battery, the lithium ion battery has the advantages of high energy density, large output power, high average output voltage, environmental friendliness, long cycle life, good safety performance and the like, and people have increasingly wide application to the lithium ion secondary battery.

The lithium ion secondary rechargeable battery consists of a battery cell and a protective circuit board. When the battery core is laminated, the pole pieces are subjected to die cutting according to the size design of the battery core before lamination, the die-cut pole pieces are mainly foil blanks in the welding area of the main pole piece and the pole lugs and are mainly used for subsequent pole lug welding, the battery pole pieces are divided into positive and negative poles, and the width/height of the blank blanks of the foils of the positive and negative pole pieces in the conventional design are designed to be the same specification, as shown in fig. 1.

However, in the process of implementing the technical solution of the invention in the embodiments of the present application, the inventors of the present application find that the above-mentioned technology has at least the following technical problems: during lamination, the phenomenon of pole piece lamination reversal/lamination overlapping is easy to occur due to manual discharging and reverse discharging/equipment faults, the number of layers of the battery cell lamination is too large, workers cannot recognize badly by naked eyes due to the fact that the width/height of the left blank of the positive pole piece and the width/height of the left blank of the negative pole piece are consistent, defective products easily flow out, and the phenomenon of combustion after battery formation charging is caused, so that serious safety accidents are caused.

Disclosure of Invention

In view of the problems existing in the related art, an object of the application is to provide a production process for avoiding cell lamination reversal, which solves the technical problems that in the prior art, due to manual emptying, reversal/equipment failure is caused, the phenomenon of pole piece lamination reversal/overlapping easily occurs, due to the fact that the blank widths/heights of positive and negative pole pieces are consistent, the number of cell lamination layers is too large, workers cannot recognize badly by naked eyes, defective products easily flow out, and combustion phenomenon occurs after cell formation charging, and major safety accidents are caused.

In order to achieve the above object, the present application provides the following technical solutions:

a production process for avoiding cell lamination stacking comprises the following steps:

step 1), respectively cutting the positive plate and the negative plate for one time to obtain the positive plate with a positive electrode welding blank area and the negative plate with a negative electrode welding blank area; wherein, the sizes of the anode welding blank area and the cathode welding blank area are different;

and 2) respectively laminating the positive plate and the negative plate which are cut once, determining whether the lamination is abnormal, if not, cutting the positive welding blank area and the negative welding blank area for the second time again, enabling the sizes of the positive welding blank area and the negative welding blank area to be the same, and then welding a tab.

Further, in the production process for avoiding the cell lamination from being stacked, in step 1), the step of making the sizes of the anode welding blank area and the cathode welding blank area different includes:

the width W1 of the anode welding blank area is larger than the width W2 of the cathode welding blank area, and the height H1 of the anode welding blank area is smaller than the height H2 of the cathode welding blank area; or

The width W1 of the welding blank area of the positive electrode is less than the width W2 of the welding blank area of the negative electrode, and the height H1 of the welding blank area of the positive electrode is greater than the height H2 of the welding blank area of the negative electrode. In the above case, the width W1 of the positive electrode welding blank region is not greater than the width W2 of the negative electrode welding blank region, and the height H1 of the positive electrode welding blank region is greater than the height H2 of the negative electrode welding blank region, because the whole positive electrode blank is wider and taller than the negative electrode, when the negative electrode is stacked inside the positive electrode sheet, the positive electrode blank completely covers the positive electrode sheet, which is not easily detected, and therefore, the width W1 of the positive electrode welding blank region must be wider or shorter or taller or shorter than the width W2 of the negative electrode welding blank region, and the height H1 of the positive electrode welding blank region must be less than the height H2 of the negative electrode welding blank region.

Further, in the production process for avoiding the cell lamination from being stacked, in step 2), the method for determining whether the lamination is abnormal includes:

and during lamination, if the size of at least one pole piece is different from the sizes of other laminations, determining that the lamination is abnormal, otherwise, determining that no abnormality exists.

Further, the finding that the size of at least one pole piece is different from the sizes of other pole pieces in the production process for avoiding the cell lamination from being overlapped comprises:

the cathode plate is mistakenly stacked on the cathode plate, and due to the size difference of the cathode plate and the anode plate, a producer can find the abnormally stacked cathode plate immediately by visual observation; or

The negative plate is mistakenly stacked on the positive plate, and due to the size difference of the negative plate and the positive plate, a producer can immediately find the abnormally stacked negative plate by visual inspection.

Further, in the production process for avoiding the cell lamination from being stacked reversely, in the step 2), if the lamination is determined to be abnormal, the abnormal pole piece is picked out and re-stacked, so that the risk of combustion/short circuit caused by the reverse stacking of the positive pole piece and the negative pole piece is avoided.

Further, the production process for avoiding the cell lamination from being overlapped,

the width W1 of the tab is less than or equal to that of the positive electrode welding blank area is less than or equal to 1/2 of the pole piece width; and/or

The width W2 of the tab is less than or equal to that of the negative electrode welding blank area is less than or equal to 1/2 of the pole piece width. The width of the welding blank area of the anode and the cathode is small, so that secondary cutting is not easy to perform; the width of the welding blank area of the anode and the cathode is larger, which is not beneficial to the stacking of the pole pieces.

Further, the production process for avoiding the cell lamination from being overlapped,

the height H1 of the welding blank area of the positive electrode is more than or equal to 5mm and less than or equal to 30 mm; and/or

The height H2 of the welding blank area of the negative electrode is less than or equal to 5mm and less than or equal to 30 mm. The height of the welding blank area of the anode and the cathode is small, so that secondary cutting is not easy to perform; the height of the welding blank area of the anode and the cathode is larger, which is not beneficial to the stacking of the pole pieces.

Further, the production process for avoiding the cell lamination from being overlapped,

the width W1 of the positive electrode welding blank area is more than or equal to 5mm, and the width W2 of the negative electrode welding blank area is more than or equal to 10 mm.

Further, the production process for avoiding the cell lamination from being overlapped,

the height H1 of the positive electrode welding blank area is more than or equal to 5mm, and the height H2 of the negative electrode welding blank area is more than or equal to 10 mm.

Further, in the production process for avoiding the cell lamination from being stacked, in the step 2), after secondary cutting, the width of the positive electrode welding blank area and the width of the negative electrode welding blank area are 10-80 mm; the height of the anode welding blank area and the height of the cathode welding blank area are 5-15 mm. The widths of the positive electrode welding blank area and the negative electrode welding blank area are mainly determined according to the widths of welding lugs, the heights of the positive electrode welding blank area and the negative electrode welding blank area are mainly determined by the design of an electric core, and the width of a top seal edge of an aluminum plastic shell is reserved during packaging.

The technical scheme provided by the application can achieve the following beneficial effects: the die cutting process designs the welding blank areas of the positive and negative pole pieces into different height/width designs, the difference between the positive and negative pole pieces can be distinguished visually by naked eyes, when the pole piece reflection phenomenon occurs in the lamination, the abnormity of the battery cell can be immediately identified, the abnormal battery cell is picked out for repair, the welding blank area cutting is carried out again after the lamination process is completed, the blank width/height is designed for the theoretical design of the battery cell, the normal welding of the battery cell is not influenced, the phenomenon of battery cell burning/short circuit caused by the reflection of the laminated pole piece is effectively avoided, and the safety and reliability of products are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of a pole piece structure to be laminated after die cutting by a conventional process;

FIG. 2 is one of the schematic structural diagrams of pole pieces to be laminated after one-time cutting by the process of the present application;

FIG. 3 is a second schematic diagram of the pole piece structure to be laminated after one cutting by the process of the present application;

in the figure: 1-positive plate, 2-negative plate, 3-positive electrode welding blank area, and 4-negative electrode welding blank area.

Detailed Description

The embodiment of the application provides a production process for avoiding the cell lamination from being stacked, and solves the technical problems that in the prior art, when the lamination is performed, the phenomenon of pole piece lamination reversal/lamination is easy to occur due to the fact that manual discharging is performed and equipment faults occur, the blank width/height of positive and negative pole pieces is consistent, the number of layers of the cell lamination is too many, workers cannot recognize badly by naked eyes, defective products are easy to flow out, and the phenomenon of combustion occurs after the cell formation charging, so that major safety accidents are caused.

In order to solve the problem of crosstalk, the technical scheme in the embodiment of the present application has the following general idea:

step 1), respectively cutting the positive plate and the negative plate for one time to obtain the positive plate with a positive electrode welding blank area and the negative plate with a negative electrode welding blank area; wherein, the sizes of the anode welding blank area and the cathode welding blank area are different;

and 2) respectively laminating the positive plate and the negative plate which are cut once, determining whether the lamination is abnormal, if not, cutting the positive welding blank area and the negative welding blank area for the second time again, enabling the sizes of the positive welding blank area and the negative welding blank area to be the same, and then welding a tab.

Can audio-visually fold the lamination and turn over electric core and choose out through above-mentioned step, avoid the defective products to flow out, avoid taking place electric core burning phenomenon, promote product factor of safety.

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

In the description of the present application, unless explicitly stated or limited otherwise, the terms "first", "second", "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "plurality" means two or more; the terms "connected," "secured," and the like are to be construed broadly and unless otherwise stated or indicated, and for example, "connected" may be a fixed connection, a removable connection, an integral connection, or an electrical connection; "connected" may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In the description of the present application, it should be understood that the term "and/or" used in the present application is only one kind of association relationship describing the associated object, and means that there may be three kinds of relationships, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

In the description of the present application, it should be understood that the terms "upper" and "lower" used in the description of the embodiments of the present application are used in a descriptive sense only and not for purposes of limitation. In addition, in this context, it will also be understood that when an element is referred to as being "on" or "under" another element, it can be directly on "or" under "the other element or be indirectly on" or "under" the other element via an intermediate element. The present application is described in further detail below with reference to specific embodiments and with reference to the attached drawings.

As shown in fig. 2 to 3, a production process for preventing cell lamination from being stacked includes the following steps:

step 1), respectively cutting the positive plate 1 and the negative plate 2 for one time to obtain the positive plate 1 with a positive electrode welding blank area 3 and the negative plate 2 with a negative electrode welding blank area 4; wherein, the sizes of the anode welding blank area 3 and the cathode welding blank area 4 are different;

and 2) respectively laminating the positive plate 1 and the negative plate 2 which are cut once, determining whether the lamination is abnormal, if not, cutting the positive welding blank area 3 and the negative welding blank area 4 for the second time again, enabling the sizes of the positive welding blank area 3 and the negative welding blank area 4 to be the same, and then welding a tab.

Further, in the production process for avoiding the cell lamination from being stacked, in step 1), the step of making the sizes of the positive electrode welding blank area 3 and the negative electrode welding blank area 4 different includes:

the width W1 of the anode welding blank area 3 is larger than the width W2 of the cathode welding blank area 4, and the height H1 of the anode welding blank area 3 is smaller than the height H2 of the cathode welding blank area 4; or

The width W1 of the welding blank region 3 of the positive electrode is less than the width W2 of the welding blank region 4 of the negative electrode, and the height H1 of the welding blank region 3 of the positive electrode is more than the height H2 of the welding blank region 4 of the negative electrode. In this case, the width W1 of the positive electrode welding blank region 3 is not greater than the width W2 of the negative electrode welding blank region 4, and the height H1 of the positive electrode welding blank region 3 is not greater than the height H2 of the negative electrode welding blank region 4, because the whole positive electrode blank is wider and higher than the negative electrode in the above case, when the negative electrode is stacked inside the positive electrode sheet 1, the positive electrode blank completely covers the positive electrode sheet 1, which is not easily detected, and therefore, the width W1 of the positive electrode welding blank region 3 is not greater than the width W2 of the negative electrode welding blank region 4, and the height H1 of the positive electrode welding blank region 3 is not greater than the height H2 of the negative electrode welding blank region 4.

Further, in the production process for avoiding the cell lamination from being stacked, in step 2), the method for determining whether the lamination is abnormal includes:

and during lamination, if the size of at least one pole piece is different from the sizes of other laminations, determining that the lamination is abnormal, otherwise, determining that no abnormality exists.

Further, the finding that the size of at least one pole piece is different from the sizes of other pole pieces in the production process for avoiding the cell lamination from being overlapped comprises:

the positive plate 1 is stacked on the negative plate 2 by mistake, and due to the size difference of the positive plate and the negative plate, a producer can find the abnormally stacked positive plate 1 immediately by visual observation; or

The negative electrode plate 2 is erroneously stacked on the positive electrode plate 1, and due to the size difference between the negative electrode plate and the positive electrode plate, a manufacturer can immediately find the abnormally stacked negative electrode plate 2 by visual observation.

Further, in the production process for avoiding the cell lamination from being stacked, in the step 2), if the lamination is determined to be abnormal, the abnormal pole piece is picked out and the lamination is performed again, so that the combustion/short circuit risk caused by the stacking of the positive pole piece and the negative pole piece 2 is avoided.

Further, the production process for avoiding the cell lamination from being overlapped,

the width W1 of the tab is less than or equal to that of the positive electrode welding blank area 3 is less than or equal to that of 1/2 pole pieces; and/or

The width W2 of the pole lug is less than or equal to that of the negative electrode welding blank area 4 is less than or equal to 1/2 pole piece width. The width of the welding blank area 4 of the anode and the cathode is small, so that secondary cutting is not easy to perform; the width of the welding blank area 4 of the positive electrode and the negative electrode is larger, which is not beneficial to the stacking of the pole pieces.

Further, the production process for avoiding the cell lamination from being overlapped,

the height H1 of the anode welding blank region 3 is less than or equal to 5mm and less than or equal to 30 mm; and/or

The height H2 of the cathode welding blank area 4 is less than or equal to 5mm and less than or equal to 30 mm. The height of the welding blank area 4 of the anode and the cathode is small, so that secondary cutting is not easy to perform; the height of the welding blank area 4 of the positive electrode and the negative electrode is larger, which is not beneficial to the stacking of the pole pieces.

Further, the production process for avoiding the cell lamination from being overlapped,

the width W1 of the positive electrode welding blank zone 3 is more than or equal to 5mm, and the width W2 of the negative electrode welding blank zone 4 is more than or equal to 10 mm.

Further, the production process for avoiding the cell lamination from being overlapped,

the height H1 of the positive electrode welding blank zone 3 is more than or equal to 5mm, and the height H2 of the negative electrode welding blank zone 4 is more than or equal to 10 mm.

Further, in the production process for avoiding the cell lamination from being stacked, in the step 2), after secondary cutting, the width of the anode welding blank area 3 and the width of the cathode welding blank area 4 are 10-80 mm; the height of the anode welding blank area 3 and the height of the cathode welding blank area 4 are 5-15 mm. The widths of the anode welding blank region 3 and the cathode welding blank region 4 are mainly determined according to the widths of welding lugs, the heights of the anode welding blank region 3 and the cathode welding blank region 4 are mainly determined by the design of an electric core, and the width of a top sealing edge of an aluminum plastic shell is reserved during packaging.

The following is described in connection with specific example 1: as shown in fig. 1, in this embodiment, after the positive electrode sheet 1 and the negative electrode sheet 2 are cut once, the width W1 of the positive electrode welding blank region 3 is 50mm, the width W2 of the negative electrode welding blank region 4 is 40mm, the height H1 of the positive electrode welding blank region 3 is 15mm, the height H2 of the negative electrode welding blank region 4 is 30mm, positive and negative electrode lamination is performed respectively, if an abnormally sized electrode sheet is found in the lamination process, the abnormally sized electrode sheet is picked out and re-laminated, if an abnormally sized electrode sheet is not found in the lamination process, secondary cutting is performed, the widths of the positive electrode welding blank region 3 and the negative electrode welding blank region 4 after secondary cutting are 30mm, and the heights of the positive electrode welding blank region 3 and the negative electrode welding blank region 4 are 15 mm.

The following is described in connection with specific example 2: as shown in fig. 2, in this embodiment, after the positive electrode sheet 1 and the negative electrode sheet 2 are cut once, the width W1 of the positive electrode welding blank region 3 is 30mm, the width W2 of the negative electrode welding blank region 4 is 35mm, the height H1 of the positive electrode welding blank region 3 is 20mm, the height H2 of the negative electrode welding blank region 4 is 10mm, positive and negative electrode lamination is performed respectively, if an abnormally sized electrode sheet is found in the lamination process, the abnormally sized electrode sheet is picked out and re-laminated, if an abnormally sized electrode sheet is not found in the lamination process, secondary cutting is performed, the widths of the positive electrode welding blank region 3 and the negative electrode welding blank region 4 after secondary cutting are 25mm, and the heights of the positive electrode welding blank region 3 and the negative electrode welding blank region 4 are 8 mm.

Variations and modifications to the above-described embodiments may also occur to those skilled in the art, which fall within the scope of the invention as disclosed and taught herein. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious improvement, replacement or modification made by those skilled in the art based on the present invention is within 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.