CN111584920B

CN111584920B - Preparation method of special-shaped battery

Info

Publication number: CN111584920B
Application number: CN202010392365.9A
Authority: CN
Inventors: 谢红斌; 张加亮
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2020-05-11
Filing date: 2020-05-11
Publication date: 2021-11-16
Anticipated expiration: 2040-05-11
Also published as: CN111584920A

Abstract

The application relates to a preparation method of a special-shaped battery, which comprises the following steps: providing a substrate unit, wherein the substrate unit comprises a positive plate, a negative plate and a diaphragm which are arranged in a laminated mode, the diaphragm is arranged between the positive plate and the negative plate, and the substrate unit has a first direction and a second direction which are perpendicular to each other. The substrate unit is cut so that the substrate unit includes at least a first substrate and a second substrate, the first substrate and the second substrate being arranged in a first direction, the first substrate and the second substrate being different in size in a second direction. And winding the second substrate around the first substrate by taking the second direction as an axis to form the battery core. The second substrate is wound around the first substrate, so that the cutting times in the cell preparation process are reduced, the burr generation probability is reduced, and the risk of short circuit in the special-shaped battery is reduced. The positive plate and the negative plate are continuous on the sides of the two ends of the first direction of the battery cell, the space utilization rate is improved, the energy density is ensured, the capacitance is increased, the shape diversification is realized, and the preparation efficiency is improved.

Description

Preparation method of special-shaped battery

Technical Field

The application relates to the technical field of batteries, in particular to a preparation method of a special-shaped battery.

Background

The conventional special-shaped battery is formed by combining a plurality of batteries, the space utilization rate is low, and the battery management is complex due to the plurality of batteries.

Disclosure of Invention

The embodiment of the application provides a preparation method of a special-shaped battery, which aims to solve the technical problem that the special-shaped battery is low in space utilization rate after a plurality of batteries are combined.

A preparation method of the special-shaped battery comprises the following steps:

providing a substrate unit, wherein the substrate unit comprises a positive plate, a negative plate and a diaphragm which are arranged in a laminated manner, the diaphragm is arranged between the positive plate and the negative plate, and the substrate unit is provided with a first direction and a second direction which are perpendicular to each other;

cutting the substrate unit so that the substrate unit includes at least a first substrate and a second substrate connected to each other, the first substrate and the second substrate being arranged in the first direction, the first substrate and the second substrate being different in size in the second direction; and

and winding the second substrate around the first substrate by taking the second direction as an axis to form the battery core.

According to the preparation method of the special-shaped battery, the positive plate, the diaphragm and the negative plate are arranged in a laminated mode to prepare the substrate unit. And cutting the substrate unit to enable the substrate unit to at least comprise a first substrate and a second substrate, wherein the first substrate and the second substrate are arranged along the first direction of the substrate unit, and the sizes of the first substrate and the second substrate in the second direction are different. And winding the second substrate around the first substrate by taking the second direction as an axis to obtain the electric core of the special-shaped battery. The second substrate is wound around the first substrate, so that the cutting times in the cell preparation process are reduced, the burr generation probability is reduced, and the risk of short circuit in the special-shaped battery is reduced. The second substrate winds around the first substrate, so that the positive plate and the negative plate are continuous on the side faces of the two ends of the electric core in the first direction, the space utilization rate of the special-shaped battery is improved, the energy density of the special-shaped battery is guaranteed, the capacitance of the special-shaped battery is increased, the shape diversification of the special-shaped battery is realized, and meanwhile, the preparation efficiency of the special-shaped battery is improved.

In one embodiment, in the step of cutting the substrate unit, the substrate unit further includes a third substrate connected to the first substrate, and the third substrate is spaced apart from the second substrate.

In one embodiment, the third substrate is aligned with the first substrate along the first direction, the second substrate and the third substrate are aligned along the second direction, and the second substrate and the third substrate are different in size in the first direction.

In one embodiment, the distance between the second substrate and the third substrate in the second direction is 0-0.1 mm.

In one embodiment, the step of winding the second substrate around the first substrate to form a cell further includes:

and winding the third substrate around the first substrate by taking the second direction as an axis.

In one embodiment, after the step of cutting the substrate unit and before the step of winding the second substrate around the first substrate to form a cell, the method further includes the following steps:

and welding a tab on one side of the first substrate along the second direction.

In one embodiment, the tabs comprise a positive tab and a negative tab, the positive tab is located on the positive plate, and the negative tab is located on the negative plate.

and welding tabs on the same side of the first substrate and the second substrate.

In one embodiment, the tabs comprise a positive tab and a negative tab; in the step of winding the second substrate around the first substrate to form the battery cell, the positive electrode tabs are overlapped, and the negative electrode tabs are overlapped.

In one embodiment, the step of providing a substrate unit comprises:

coating an anode active substance on an aluminum foil to prepare the anode plate, coating a cathode active substance on a copper foil to prepare the cathode plate, and laminating the anode plate, the diaphragm and the cathode plate to prepare the substrate unit.

In one embodiment, after the step of winding the second substrate around the first substrate to form the battery cell, the method further includes the following steps:

and placing the electric core into an aluminum plastic film to obtain the special-shaped battery.

Drawings

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

Fig. 1 is a perspective view of a special-shaped battery provided in an embodiment;

fig. 2 is a perspective view of the anisotropic battery shown in fig. 1, in which an aluminum plastic film is removed;

FIG. 3 is an enlarged view of the part A of the special-shaped battery shown in FIG. 2;

FIG. 4 is a flow chart of an embodiment of a method for manufacturing a shaped battery;

fig. 5 is a flow chart for preparing a special-shaped battery according to another embodiment;

FIG. 6 is a flow chart illustrating the process of manufacturing a shaped battery according to yet another embodiment;

FIG. 7 is a schematic view of a substrate unit provided in one embodiment;

FIG. 8 is a schematic view of a substrate unit according to another embodiment;

FIG. 9a is a schematic view of a substrate unit provided in one embodiment after being diced;

FIG. 9b is a schematic view of a substrate unit provided in another embodiment after being diced;

fig. 10 is a schematic view of the substrate unit and tab shown in fig. 9;

fig. 11 is a perspective view of the substrate unit of fig. 10 wound to form a cell in one embodiment;

fig. 12 is a perspective view of the substrate unit of fig. 10 wound to form a cell in another embodiment;

FIG. 13 is a schematic view of the substrate unit of FIG. 9 after placement of tabs;

fig. 14 is a perspective view of the substrate unit shown in fig. 13 wound and clad with an aluminum plastic film to form a shaped battery.

Detailed Description

To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present application are illustrated in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

As used herein, "terminal device" refers to a device capable of receiving and/or transmitting communication signals including, but not limited to, devices connected via any one or more of the following connections:

(1) via wireline connections, such as via Public Switched Telephone Network (PSTN), Digital Subscriber Line (DSL), Digital cable, direct cable connections;

(2) via a Wireless interface means such as a cellular Network, a Wireless Local Area Network (WLAN), a digital television Network such as a DVB-H Network, a satellite Network, an AM-FM broadcast transmitter.

A terminal device arranged to communicate over a wireless interface may be referred to as a "mobile terminal". Examples of mobile terminals include, but are not limited to, the following electronic devices:

(1) satellite or cellular telephones;

(2) personal Communications Systems (PCS) terminals that may combine cellular radiotelephones with data processing, facsimile, and data Communications capabilities;

(3) radiotelephones, pagers, internet/intranet access, Web browsers, notebooks, calendars, Personal Digital Assistants (PDAs) equipped with Global Positioning System (GPS) receivers;

(4) conventional laptop and/or palmtop receivers;

(5) conventional laptop and/or palmtop radiotelephone transceivers, and the like.

As shown in fig. 1, in an embodiment, a special-shaped battery 10 is provided, which can be applied to an electronic device to supply power to the electronic device. The shape of the shaped battery 10 may be L-shaped, T-shaped, or other shapes, and is not particularly limited herein. It can be understood that, electronic components are arranged in the electronic device, the space reserved for the battery is not necessarily regular square, and the shape of the special-shaped battery 10 can be designed according to the shape of the space reserved for the battery in the electronic device, so that the special-shaped battery 10 can be accommodated in the electronic device, and the space inside the electronic device is effectively utilized. Compared with the square battery with a regular shape, the special-shaped battery 10 effectively utilizes the space in the electronic equipment, and has a larger volume than the square battery with a regular shape which can be accommodated by the electronic equipment, so that the electric capacity of the special-shaped battery 10 is larger than the square battery with a regular shape which can be accommodated by the electronic equipment. In the present application, the irregular shaped battery 10 will be described in detail as an example of an L-shaped battery.

As shown in fig. 1 and 2, in an embodiment, the special-shaped battery 10 includes a battery core 20, an aluminum plastic film 30 wrapping the battery core 20, and tabs 200. The aluminum-plastic film 30 wraps the battery core 20, so that the shape of the battery core 20 can be fixed, and the battery core 20 is isolated from the external environment, thereby preventing the electric leakage of the special-shaped battery 10 in the use process, and simultaneously preventing the pollution of the battery core 20 to objects in contact with the battery core. The battery cell 20 is provided therein with a positive electrode tab 110, a separator 120, and a negative electrode tab 130 (shown in fig. 7). The number of the positive electrode plates 110 may be one or more, the number of the negative electrode plates 130 is equal to that of the positive electrode plates 110, and the positive electrode plates 110 and the negative electrode plates 130 are separated by the separator 120 to avoid a chemical reaction between the positive electrode plates 110 and the negative electrode plates 130. It can be understood that the surface of the battery cell 20 is separated from the aluminum plastic film 30 by the diaphragm 120, so as to avoid the leakage of electricity from the battery cell 20 and the contamination of external objects. The tabs 200 include a positive tab 210 and a negative tab 220. The positive tab 210 is connected to the positive plate 110, and the negative tab 220 is connected to the negative plate 130. In one embodiment, the positive tab 210 is welded to the positive plate 110, and the negative tab 220 is welded to the negative plate 130. In another embodiment, the positive tab 210 and the positive plate 110 and the negative tab 220 and the negative plate 130 are connected by other methods, which are not limited herein.

As shown in fig. 1, in one embodiment, the shaped battery 10 has two perpendicular X, Y and Z directions. The length direction of the irregular-shaped battery 10 is set along the Y direction, the width direction is set along the X direction, and the thickness direction is set along the Z direction. In one embodiment, the shaped battery 10 includes a first surface 11 and a second surface 12 disposed opposite each other, and a first side 13 and a second side 14 disposed opposite each other. The first side 13 is connected to one ends of the first surface 11 and the second surface 12, and the second side 14 is connected to the other ends of the first surface 11 and the second surface 12. The first surface 11 and the second surface 12 are substantially parallel, the first surface 11 and the second surface 12 define a thickness of the shaped battery 10, the first side 13 and the second side 14 are substantially parallel, and the first side 13 and the second side 14 define a length of the shaped battery 10. The shaped battery 10 also includes a third side 15, a fourth side 16, and a fifth side 17. The third side 15, the fourth side 16 and the fifth side 17 are substantially parallel. The third side 15 and the fourth side 16 are located on the same side of the shaped cell 10 and the fifth side 17 is located on the other side of the shaped cell 10. There is a height difference between the third side 15 and the fourth side 16 such that the distance between the third side 15 and the fifth side 17 is greater than the distance between the fourth side 16 and the fifth side 17, thereby causing the shaped battery 10 to assume an L-shape. The third side 15 and the fifth side 17 define the width of the profiled cell 10.

As shown in fig. 2 and 3, in one embodiment, the positive electrode sheet 110, the separator 120, and the negative electrode sheet 130 are stacked in the longitudinal direction, i.e., the Y direction, of the irregular battery 10, i.e., near the first side 13 and the second side 14, i.e., the positive electrode sheet 110, the separator 120, and the negative electrode sheet 130 have a cross section near the first side 13 and the second side 14. It is understood that the positive electrode tab 110, the separator 120, and the negative electrode tab 130 are disposed like a laminated paper sheet near the first side 13 and the second side 14, and the side formed by the positive electrode tab 110, the separator 120, and the negative electrode tab 130 disposed in a lamination is approximately equal to the area of the first side 13 and the second side 14. The positive electrode tab 210 and the negative electrode tab 220 are respectively connected to the positive electrode sheet 110 and the negative electrode sheet 130 at the first side surface 13; alternatively, the positive and

negative electrode tabs

210 and 220 are connected to the positive and

negative electrode tabs

110 and 130, respectively, at the second side 14. It can be understood that, due to the cross section of the positive electrode tab 110 and the negative electrode tab 130 near the first side surface 13 and the second side surface 14, the positive electrode tab 210 and the negative electrode tab 220 can extend between the positive electrode tab 110 and the negative electrode tab 130 which are stacked, so that the positive electrode tab 210 can be welded to the positive electrode tab 110, and the negative electrode tab 220 can be welded to the negative electrode tab 220. It is understood that the step of welding the positive electrode tab 210 and the negative electrode tab 220 with the positive electrode sheet 110 and the negative electrode sheet 130 is prior to the step of wrapping the battery cell 20 with the aluminum plastic film 30.

As shown in fig. 2 and 3, in one embodiment, the positive electrode sheet 110, the separator 120, and the negative electrode sheet 130 are wound at both ends of the profiled battery 10 in the width direction, i.e., the X direction. It is understood that after the positive electrode sheet 110, the separator 120, and the negative electrode sheet 130 are stacked, winding is performed with the Y direction as an axis such that both ends of the positive electrode sheet 110, the separator 120, and the negative electrode sheet 130 in the Y direction are substantially flush in cross section and both ends in the X direction are in a wound stacked structure. The positive plate 110 and the negative plate 130 which are parallel to the YZ plane are arranged at the two ends of the special-shaped battery 10 in the X direction, so that the sides of the positive plate 110 and the negative plate 130 at the two ends of the X direction are continuous, the space utilization rate of the special-shaped battery 10 is improved, and the capacitance of the special-shaped battery 10 is increased.

As shown in fig. 4, in one embodiment, a method for manufacturing the special-shaped battery 10 is provided, which includes the following steps:

providing a substrate unit 100, wherein the substrate unit 100 comprises a positive plate 110, a negative plate 130 and a diaphragm 120 which are arranged in a laminated manner, the diaphragm 120 is arranged between the positive plate 110 and the negative plate 130, and the substrate unit 100 has a first direction and a second direction which are perpendicular to each other;

cutting the substrate unit 100 such that the substrate unit 100 includes at least a first substrate 101 and a second substrate 102 connected to each other, the first substrate 101 and the second substrate 102 being arranged in a first direction, the first substrate 101 and the second substrate 102 differing in size in a second direction; and

the second substrate 102 is wound around the first substrate 101 with the second direction as an axis to form the battery cell 20.

As shown in fig. 5 and 7, in one embodiment, a positive electrode sheet 110 is prepared by applying a positive electrode active material to an aluminum foil, and a negative electrode sheet 130 is prepared by applying a negative electrode active material to a copper foil. In one embodiment, the positive and negative electrode active materials may be graphite; after the positive electrode active material and the negative electrode active material are respectively coated on the aluminum foil and the copper foil, baking and rolling are carried out, then cutting and tidying are carried out according to the design sizes of the positive electrode sheet 110 and the negative electrode sheet 130, and the positive electrode sheet 110, the diaphragm 120 and the negative electrode sheet 130 are arranged in a mode that the positive electrode sheet 110 and the negative electrode sheet 130 are respectively positioned on two sides of the diaphragm 120, so that the positive electrode sheet 110, the diaphragm 120 and the negative electrode sheet 130 are sequentially stacked and arranged in order, the positive electrode sheet 110, the diaphragm 120 and the negative electrode sheet 130 are formed to be compounded and integrated, and the substrate unit 100 is manufactured. It is understood that the substrate unit 100 includes a positive electrode tab 110, a negative electrode tab 130, and a separator 120, and the separator 120 is located between the positive electrode tab 110 and the negative electrode tab 130.

As shown in fig. 7, in an embodiment, the battery cell 20 is formed by stacking a plurality of substrate units 100, and the number of the substrate units 100 is selected according to the designed thickness of the irregular battery 10. The different substrate units 100 are stacked, and the surfaces of the substrate units 100 positioned at the topmost layer and the bottommost layer are covered with the separator 120 so that the positive electrode tab 110 and the negative electrode tab 130 are isolated from external objects.

In another embodiment, as shown in fig. 8, the battery cell 20 is prepared from a substrate unit 100. The surfaces of both sides of the substrate unit 100 are covered with separators 120 to isolate the positive and

negative electrode tabs

110 and 130 from the outside.

As shown in fig. 9a and 9b, in one embodiment, after one or more stacked substrate units 100 are provided with a membrane 120 on the stacked surface, the substrate units 100 are cut according to design requirements. The substrate unit 100 has a first direction and a second direction perpendicular to each other, the first direction being disposed along the X-axis and the second direction being disposed along the Y-axis. As shown in fig. 9a, in one embodiment, the cut substrate unit 100 includes a first substrate 101 and a second substrate 102, and the first substrate 101 and the second substrate 102 are arranged in a first direction, i.e., an X direction. In the Y direction, the size of the first substrate 101 is larger than that of the second substrate 102. It is understood that the cutting process is to cut a certain area of the substrate unit 100, and the first substrate 101 and the second substrate 102 are integrally formed. A virtual first boundary line L1 exists between the first substrate 101 and the second substrate 102. It is understood that the first dividing line L1 is substantially parallel to the Y-axis, and a height difference exists between the boundary of the first substrate 101 parallel to the first dividing line L1 and the first dividing line L1. The second substrate 102 is wound around the first substrate 101 with the second direction, i.e., the Y-axis, as a rotation axis, to obtain the L-shaped cell 20.

As shown in fig. 9b, in one embodiment, the diced substrate unit 100 includes a first substrate 101, a second substrate 102 and a third substrate 103. The first substrate 101 and the second substrate 102 are arranged in a first direction, i.e., the X direction, the third substrate 103 and the first substrate 101 are arranged in the X direction, and the second substrate 102 and the third substrate 103 are arranged in a second direction, i.e., the Y direction. The dimensions of the second substrate 102 and the third substrate 103 are different in the first direction, i.e., the X direction. In one embodiment, the distance between the second substrate 102 and the third substrate 103 is 0-0.1 mm in the second direction, i.e., the Y direction. A virtual second boundary line L2 exists between the first substrate 101 and the third substrate 103. It is understood that the second boundary line L2 is substantially parallel to the Y-axis, and that there is a height difference between the second boundary line L2 and the first boundary line L1. The second substrate 102 is wound around the first substrate 101, and the third substrate 103 is wound around the first substrate 101 with the second direction, i.e., the Y-axis, as a rotation axis, so that the L-shaped battery cell 20 shown in fig. 11 is obtained.

As shown in fig. 5 and 10, in an embodiment, after the step of cutting the substrate unit 100, before the step of winding the second and

third substrates

102 and 103 around the first substrate 101, a step of providing tabs 200 on the substrate unit 100 is further included. In one embodiment, the tab 200 is disposed on one side of the first substrate 101 in the Y direction, so that the tab 200 can be exposed out of the wound battery cell 20, so that the tab 200 can be electrically connected to an electrical connection point of an electronic device. Specifically, the tabs 200 include a positive tab 210 and a negative tab 220, the positive tab 210 is welded to the positive plate 110, the negative tab 220 is welded to the negative plate 130, and the positive tab 210 and the negative tab 220 are located on the same side of the first substrate 101. As shown in fig. 10 and 11, in an embodiment, the positive electrode tab 210 and the negative electrode tab 220 are both located on one side of the first substrate 101 in the Y direction, and the second substrate 102 and the third substrate 103 are wound around the first substrate 101, so that the battery cell 20 shown in fig. 11 is obtained. In another embodiment, the positive electrode tab 210 and the negative electrode tab 220 are designed to be located on the other side of the first substrate 101 in the Y direction, and then the second substrate 102 and the third substrate 103 are wound around the first substrate 101, so as to obtain the battery cell 20 shown in fig. 12.

As shown in fig. 13, in one embodiment, a positive tab 210 and a negative tab 220 are disposed on one side of the first substrate 101, and the positive tab 210 and the negative tab 220 are disposed on the same side of the second substrate 102 as the first substrate 101 on which the tabs 200 are disposed. It is understood that the positive electrode tab 210 is welded to the positive electrode sheet 110 and the negative electrode tab 220 is welded to the negative electrode sheet 130. As viewed in fig. 13, the positive electrode tab 210 and the negative electrode tab 220 are disposed on the right side of the first substrate 101, and one or more sets of the positive electrode tab 210 and the negative electrode tab 220 are disposed on the right side of the second substrate 102. After the second substrate 102 is wound around the first substrate 101, all the positive tabs 210 are overlapped, and all the negative tabs 220 are overlapped, so as to obtain the battery cell 20 represented as a group of tabs 200 as shown in fig. 11. Because of the plurality of positive electrode tabs 210 and the plurality of negative electrode tabs 220, the positive electrode sheet 110 and the negative electrode sheet 130 are in a parallel connection state, so that the internal resistance value of the special-shaped battery 10 is reduced, and the application of a large-current quick-charging battery is facilitated.

In another embodiment, the left side of the first substrate 101 is provided with a positive electrode tab 210 and a negative electrode tab 220, and the left side of the third substrate 103 is provided with a positive electrode tab 210 and a negative electrode tab 220. After the third substrate 103 is wound around the first substrate 101, all the positive tabs 210 are overlapped, and all the negative tabs 220 are overlapped, so as to obtain the battery cell 20 presenting a group of tabs 200 as shown in fig. 12.

As shown in fig. 14, in an embodiment, an aluminum-plastic film 30 is provided, which is pre-punched, and the battery cell 20 is placed in the aluminum-plastic film 30 to obtain the special-shaped battery 10. The aluminum-plastic film 30 wraps the battery cell 20 to isolate the battery cell 20 from the outside, thereby avoiding electric leakage or pollution to external objects.

According to the preparation method of the heteromorphic battery 10, the substrate unit 100 is prepared by laminating the positive electrode sheet 110, the diaphragm 120 and the negative electrode sheet 130. The substrate unit 100 is cut such that the substrate unit 100 includes at least a first substrate 101 and a second substrate 102, the first substrate 101 and the second substrate 102 are arranged along a first direction, i.e., an X direction, of the substrate unit 100, and sizes of the first substrate 101 and the second substrate 102 in a second direction, i.e., a Y direction, are different. And winding the second substrate 102 around the first substrate 101 by taking the second direction, namely the Y axis, as the axis to obtain the battery core 20 of the special-shaped battery 10. The second substrate 102 is wound around the first substrate 101, so that the cutting times in the preparation process of the battery cell 20 are reduced, the burr generation probability is reduced, and the risk of internal short circuit of the special-shaped battery 10 is reduced. The second substrate 102 is wound around the first substrate 101, so that the positive plate 110 and the negative plate 130 are continuous on the sides of the two ends of the electric core 20 in the X direction, the space utilization rate of the special-shaped battery 10 is improved, the energy density of the special-shaped battery 10 is ensured, the electric capacity of the special-shaped battery 10 is increased, the form diversification of the special-shaped battery 10 is realized, and the preparation efficiency of the special-shaped battery 10 is also improved. By arranging the positive pole lug 210 and the negative pole lug 220 on the same side of the first substrate 101 and the second substrate 102, after the second substrate 102 is wound around the first substrate 101, all the positive pole lugs 210 are overlapped, and all the negative pole lugs 220 are overlapped, so that the lugs 200 in different groups are in a parallel state, the internal resistance value is reduced, and the application of a high-current quick-charging battery is facilitated.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The preparation method of the special-shaped battery is characterized by comprising the following steps:

cutting the substrate unit so that the substrate unit includes at least a first substrate and a second substrate connected to each other, and a third substrate connected to the first substrate, the first substrate and the second substrate being arranged in the first direction, the first substrate and the second substrate being different in size in the second direction; the third substrate and the second substrate are arranged at intervals; the third substrate and the first substrate are arranged along the first direction, the second substrate and the third substrate are arranged along the second direction, and the sizes of the second substrate and the third substrate are different in the first direction;

welding tabs on the same side of the first substrate and the second substrate, wherein the tabs comprise a positive tab and a negative tab;

and

and winding the second substrate and the third substrate around the first substrate by taking the second direction as an axis to form a battery cell, wherein the positive pole lugs are overlapped, and the negative pole lugs are overlapped.

2. The method for preparing the special-shaped battery according to claim 1, wherein the distance between the second substrate and the third substrate in the second direction is 0-0.1 mm.

3. The method for preparing the special-shaped battery according to claim 1, wherein after the step of cutting the substrate unit and before the step of winding the second substrate around the first substrate to form a battery cell, the method further comprises the following steps:

4. The method for preparing the special-shaped battery according to claim 3, wherein the tabs comprise a positive tab and a negative tab, the positive tab is positioned on the positive plate, and the negative tab is positioned on the negative plate.

5. The method of claim 1, wherein the step of providing a substrate unit comprises:

6. The method for preparing the special-shaped battery according to claim 1, wherein the step of winding the second substrate around the first substrate to form a battery cell further comprises the following steps: