WO2022082952A1

WO2022082952A1 - Battery protection circuit board and manufacturing method therefor

Info

Publication number: WO2022082952A1
Application number: PCT/CN2020/134486
Authority: WO
Inventors: 向付羽; 邓先友; 刘金峰; 张河根; 王荧
Original assignee: 深南电路股份有限公司
Priority date: 2020-10-20
Filing date: 2020-12-08
Publication date: 2022-04-28
Also published as: CN114390778A

Abstract

A battery protection circuit board and a manufacturing method therefor. The battery protection circuit board comprises a battery protection hard board and a battery protection soft board, and the battery protection hard board is connected to the battery protection soft board by means of a flexible substrate (P); the battery protection soft board comprises a first copper layer (1) and a second copper layer (2) located at two opposite sides of the flexible substrate (P); the battery protection hard board comprises a third copper layer (3) and a fourth copper layer (4) located at two opposite sides of the flexible substrate (P), and a hard board protection layer (P1) located on the other side of the fourth copper layer (4) with respect to the flexible substrate (P); the first copper layer (1) and the third copper layer (3) are provided on the same side of the flexible substrate (P), wherein a connector pad is provided on the first copper layer (1), and a component pad is provided on the third copper layer (3). The present method can achieve one-time solder printing on the connector pad and the component pad of the battery protection circuit board.

Description

A kind of battery protection circuit board and its manufacturing method

【Technical field】

The invention relates to the field of battery protection, in particular to a battery protection circuit board and a manufacturing method thereof.

【Background technique】

The battery protection board is an integrated circuit board that protects the rechargeable battery. The protection function of the battery is usually completed by the protection circuit board and other current devices. The voltage and the current of the charging and discharging loop can be controlled instantly to control the on-off of the current loop. The so-called battery protection is overcharge protection, overdischarge protection, overcurrent, short circuit protection and ultra-high temperature charge and discharge protection. The battery protection board is the safety guarantee for the mobile phone battery and even the entire mobile phone. With the commercial use of 5G, it brings users a faster Internet experience and more intelligent applications, and the hardware cost of mobile phones is gradually increasing. Reflected in the battery module, the battery protection circuit board mostly adopts a flexible and rigid combination board, that is, the battery protection circuit board is divided into a hard board area connected to the battery, and a flexible board area that can be bent freely. connected.

In the prior art, since the pads of the soft board connector and the pads of the hard board components are not on the same side or the pads of the soft and hard board are designed on the same side, there is a height difference between the soft board area and the hard board area, and the expansion and contraction do not match. As a result, the battery protection circuit board cannot be assembled by brushing tin at one time.

[Content of the invention]

The present application provides a battery protection circuit board and a manufacturing method thereof, which solves the problem that the battery protection circuit board cannot be tin brushed at one time due to the height difference between the soft board connector pad and the hardware component pad in the prior art.

In order to solve the above problems, the present application provides a battery protection circuit board, the battery protection circuit board includes a battery protection hard board and a battery protection soft board, and the battery protection hard board and the battery protection soft board are connected through a flexible substrate; The board includes a first copper layer and a second copper layer located on opposite sides of the flexible substrate; the battery protection hard board includes a third copper layer and a fourth copper layer located on opposite sides of the flexible substrate, and the fourth copper layer is located on the opposite side. The hard board protective layer on the other side of the flexible substrate; the first copper layer and the third copper layer are arranged on the same side of the flexible substrate, wherein the first copper layer is provided with connector pads, and the third copper layer is provided with element device pads.

Wherein, the second copper layer of the battery protection soft board and the fourth copper layer of the battery protection hard board are arranged on the same side of the flexible substrate.

The thicknesses of the first copper layer and the third copper layer are the same, and the thicknesses of the second copper layer and the fourth copper layer are the same.

Wherein, the battery protection soft board also includes a soft board protective layer, the soft board protective layer is located on the side of the second copper layer away from the flexible substrate, the soft board protective layer includes a thermosetting adhesive layer and a reinforcing film layer; the battery protection hard board includes Hard board protective layer, the hard board protective layer includes a first hard board protective layer and a second hard board protective layer; the first hard board protective layer is located on the other side of the fourth copper layer relative to the flexible substrate; the second hard board protection layer The layer includes a fifth copper layer and a sixth copper layer on opposite sides on the other side of the first rigid board protective layer relative to the fourth copper layer.

Wherein, the battery protection soft board further includes at least one via hole, and the via hole in the soft board area penetrates the first copper layer, the flexible substrate and the second copper layer.

Wherein, the battery protection hard board further includes at least one via hole, the via hole in the hard board area penetrates the third to sixth copper layers, and between the third and sixth copper layers includes a flexible substrate, a fourth copper layer layer, the first hard board protective layer, the fifth copper layer, the second hard board protective layer.

The present application also provides a method for making a battery protection circuit board, including: providing a battery protection hard board and a battery protection soft board; making a first copper layer and a second copper layer on the opposite sides of the battery protection soft board, A third copper layer and a fourth copper layer are made on the opposite sides of the protection hard board; the battery protection soft board and the battery protection hard board are butt-assembled, so that the first copper layer and the third copper layer are arranged on the same layer.

Among them, the connector pads are fabricated on the first copper layer, the component pads are fabricated on the third copper layer, and the connector pads and the component pads are brushed with tin once.

Wherein, the step of assembling the battery protection soft board and the battery protection hard board so that the first copper layer and the third copper layer are arranged on the same layer includes: docking and assembling the second copper layer and the fourth copper layer.

Wherein, a soft board protective layer is made on the surface of the second copper layer away from the first copper layer; the soft board protective layer includes a thermosetting adhesive layer and a reinforcing film layer; the surface of the fourth copper layer is made away from the third copper layer. The board protective layer, the hard board protective layer at least includes a first hard board protective layer and a second hard board protective layer and a fifth copper layer and a sixth copper layer.

The beneficial effects of the present application are as follows: the present application provides a battery protection circuit board and a manufacturing method thereof, the battery protection circuit board includes a battery protection hard board and a battery protection soft board, the third copper layer of the battery protection hard board and the battery protection soft board The first copper layer of the board is arranged on the same layer, and the first copper layer and the third copper layer can be tin brushed once, avoiding multiple tin brushing of multiple connector pads and device pads.

【Description of drawings】

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the drawings that are used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a schematic structural diagram of an embodiment of a battery protection circuit board in the prior art;

FIG. 2 is a schematic structural diagram of an embodiment of a battery protection circuit board of the present application;

3 is a schematic flowchart of an embodiment of a method for manufacturing a battery protection circuit board of the present application;

FIG. 4 is a schematic flowchart of another embodiment of the method for fabricating a battery protection circuit board of the present application.

【Detailed ways】

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that if there are directional indications (such as up, down, left, right, front, back, etc.) involved in the embodiments of the present invention, the directional indications are only used to explain a certain posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly.

In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for the purpose of description, and should not be construed as indicating or implying Its relative importance or implicitly indicates the number of technical features indicated. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In addition, the technical solutions between the various embodiments can be combined with each other, but must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that the combination of such technical solutions does not exist. , is not within the scope of protection required by the present invention.

Please refer to FIG. 1 . FIG. 1 is a schematic structural diagram of an embodiment of a battery protection circuit board in the prior art. As shown in Figure 1, the left side is the hard board area of the battery protection circuit board, and the right side is the soft board area of the battery protection circuit board. Wherein, the hard board area and the soft board area are connected by a flexible substrate.

The flexible board area includes a first copper layer 1, a flexible substrate P, and a second copper layer L2. The first copper layer 1 and the second copper layer 2 are located on the upper and lower sides of the flexible substrate. The soft board area also includes a first soft board protective layer C1 and a second soft board protective layer C2, the first soft board protective layer C1 is located on the surface of the first copper layer 1 away from the flexible substrate P, and the second soft board protective layer is located far away from the flexible board P. The surface of the second copper layer 2 of the substrate P.

The hard board area includes a third copper layer 3 , a first hard board protective layer P1 , a fourth copper layer 4 , a flexible substrate P, a fifth copper layer 5 , a second hard board protective layer P2 , and a sixth copper layer 6 . The fourth copper layer 4 and the fifth copper layer 5 are located on the upper and lower sides of the flexible substrate 1 , and the first hard board protective layer P1 and the second hard board protective layer P2 are respectively located on the fourth copper layer 4 and the fifth copper layer 5 The third copper layer 3 and the sixth copper layer 6 are respectively located on the surfaces of the first hard board protective layer P1 and the second hard board protective layer P2.

The connector pads in the soft board area can be arranged on the first copper layer 1 in the soft board area on the second copper layer 2, and the component pads in the hard board area are arranged on the third copper layer 3 and the sixth copper layer 6 . Taking one side as an example, when the connector pads are arranged on the first copper layer 1 and the component pads are arranged on the third copper layer 3, it can be seen from FIG. The disks are arranged on the same side, but due to the different thicknesses of the hard board protective layer in the hard board area and the soft board protective layer in the soft board area, the first copper layer 1 provided with the connector pads and the component pads provided with the There is a height difference in the third copper layer 3, so that it is impossible to brush tin on the connector pads and the component pads once. When the connector pads are arranged on the second copper layer 2 and the component pads are arranged on the third copper layer 3, the connector pads and the component pads are not on the same side, and the connector pads and components cannot be soldered. The plate is tin brushed once.

As can be seen from Figure 1, in the prior art, the hard board area of the battery protection board adopts a top-bottom symmetrical structure, and the soft board area also adopts a top-bottom symmetrical structure, and the connector pads are arranged on the outermost copper layer of the soft board area. On the surface, the component pads are arranged on the outermost copper layer of the hard board area. Due to the height difference between the soft board area and the hard board area, and the mismatch between the expansion and contraction of the soft board protective layer and the hard board protective layer, the connection is caused. The copper layers of the connector pads and the component pads are not on the same plane, so it is impossible to brush the connector pads and component pads of the battery protection circuit board once.

The present application provides a battery protection circuit board. Please refer to FIG. 2 , which is a schematic structural diagram of an embodiment of the battery protection circuit board of the present application. The battery protection circuit board of the present application includes a battery protection soft board and a battery protection hard board. Wherein, the battery protection soft board and the battery protection hard board are connected through a flexible substrate P. As shown in FIG. 2 , the battery protection flexible board is an area on the right side including the first copper layer 1 , the flexible substrate P, and the second copper layer 2 . The battery protection hard board on the left side includes a third copper layer 3, a flexible substrate P, a fourth copper layer 4, a first hard board protective layer P1, a fifth copper layer 5, a second hard board protective layer P2 and a sixth copper layer 6 area.

Specifically, the first copper layer 1 and the second copper layer 2 are located on opposite sides of the flexible substrate of the battery protection flexible board. The third copper layer 3 and the fourth copper layer 4 are located on opposite sides of the flexible substrate of the battery protection hard board, and the hard board protection layer is located on one side of the fourth copper layer 4 away from the flexible substrate.

In this embodiment, the first copper layer 1 of the battery protection soft board and the third copper layer 3 of the battery protection hard board are disposed on the same side of the flexible substrate P. As shown in FIG. Specifically, the thicknesses of the first copper layer 1 and the third copper layer 3 are the same.

In this embodiment, connector pads are formed on the surface of the first copper layer 1 of the battery protection soft board, and component pads are formed on the surface of the third copper layer 3 of the battery protection hard board.

Preferably, the component pads are used to connect the battery of the mobile phone, and the connector pads are used to connect various parts in the mobile phone.

Preferably, a soft board protective layer C1 is provided on the surface of the second copper layer 2 of the battery protection soft board away from the first copper layer 1 , and the soft board protective layer includes a thermosetting adhesive layer and a reinforcing film layer, wherein the reinforcing film layer can be FR4, SUS steel sheet, PI, etc.

Preferably, a hard board protective layer is provided on the surface of the fourth copper layer 4 that is far from the third copper layer 3 of the battery protection hard board. The hard board protective layer includes a first hard board protective layer P1 and a second hard board protective layer P2. The thickness of the hard board protective layer P1 is greater than the thickness of the soft board protective layer C1. The first hard board protective layer P1 is a polystyrene colloid, and in other embodiments, it can also be other materials, which is not limited here. The surface of the first hard board protective layer P1 away from the fourth copper layer 4 is provided with a fifth copper layer 5, and the surface of the fifth copper layer 5 away from the first hard board protective layer is provided with a second hard board protective layer P2. A sixth copper layer 6 is provided on the surface of the board protection layer P2 away from the fifth copper layer 5 .

Preferably, a green oil protective layer is further provided on the surfaces of the first copper layer 1 provided with the connector pads and the third copper layer 3 provided with the component pads.

Preferably, a white oil protective layer is provided on the surface of the soft board protective layer C1, and a green oil protective layer is provided on the surface of the sixth copper layer 6 on the surface of the hard board protective layer.

The beneficial effects of this embodiment are: by setting the soft board protective layer on the surface of the second copper layer of the battery protection soft board away from the first copper layer provided with the connector pads, and by setting the battery protection hard board away from the component soldering The surface of the fourth copper layer of the third copper layer of the disk is provided with a hard board protective layer, so that the first copper layer provided with the connector pads and the third copper layer provided with the component pads are on the same copper layer. The structure of the battery protection circuit board provided in this embodiment can perform tin brushing on the pads of the battery protection circuit board once.

In this embodiment, the battery protection flexible board includes at least one through hole, and the through hole of the battery protection flexible board penetrates the first copper layer 1 , the flexible board substrate, and the second copper layer 2 in the flexible board area.

Preferably, the battery protection hard board includes at least one via hole, and the via hole in the hard board area penetrates all the dielectric layers between the third copper layer 3 to the sixth copper layer 6, and specifically, penetrates through the third copper layer in the hard board area. Copper layer 3 , flexible substrate, fourth copper layer 4 , first hard board protective layer P1 , fifth copper layer 5 , second hard board protective layer P2 , sixth copper layer 6 .

Preferably, a green oil protective layer is provided on the surface of the first copper layer 1, the third copper layer 3 and the via hole. A green oil protective layer is arranged on the surface of the sixth copper layer 6 and the via hole.

The beneficial effect of this embodiment is: by setting the via holes in the battery protection soft board area and the battery protection hard board area respectively, the battery protection circuit board has both soft board characteristics and hard board characteristics, without changing the flexible and rigid board. Under the characteristic, the connector pads and the component pads of the battery protection circuit board are arranged on the same copper layer, so that it is convenient to brush tin at one time.

The present application also provides a method for manufacturing a battery protection circuit board, as shown in FIG. 3 , which is a schematic flowchart of an embodiment of the method for manufacturing a battery protection circuit board of the present application. Specifically include:

Step S31: Provide a battery protection hard board and a battery protection soft board.

The battery protection soft board and the battery protection hard board are connected by a flexible substrate. Preferably, the flexible substrate is a PI substrate with bendable properties.

Step S32 : forming a first copper layer and a second copper layer on opposite sides of the battery protection soft board, and forming a third copper layer and a fourth copper layer on the opposite sides of the battery protection hard board.

The battery protection soft board includes a flexible substrate and a first copper layer and a second copper layer on opposite sides of the flexible substrate. The battery protection hard board includes a flexible substrate, a third copper layer and a fourth copper layer on opposite sides of the flexible substrate, and a hard board protection layer on the other side of the fourth copper layer relative to the flexible substrate.

Preferably, the battery protection soft board further includes a soft board protective layer, and the soft board protective layer is located on the other side of the second copper layer relative to the flexible substrate.

Step S33 : assembling the battery protection hard board and the battery protection soft board, so that the first copper layer and the third copper layer are arranged on the same layer.

Assemble the battery protection hard board and the battery protection soft board to form a complete battery protection circuit board. Wherein, the process of docking and assembling the battery protection hard board and the battery protection soft board also includes: docking and assembling the flexible substrate of the battery protection soft board and the battery protection hard board, and assembling the second copper layer of the battery protection soft board. Butt assembly with the fourth copper layer of the battery protection hard board.

The connector pads are made on the first copper layer of the battery protection soft board, and the component pads are made on the second copper layer of the battery protection hard board.

In this embodiment, the thicknesses of the first copper layer and the second copper layer are the same, and the thicknesses of the first hard board protective layer and the flexible board protective layer are different.

Optionally, after the battery protection hard board and the battery protection soft board are butted and assembled, tin brushing is performed on the connector pads of the first copper layer and the component pads of the third copper layer.

Optionally, a soft board protective layer is made on the surface of the second copper layer of the battery protection soft board, and the soft board protective layer includes a soft board protective glue layer and a soft board cover film layer.

Optionally, a hard board protective layer is made on the surface of the fourth copper layer of the battery protection hard board, and the hard board protective layer includes a first hard board protective layer and a second hard board protective layer, and the opposite sides of the second hard board protective layer. the fifth copper layer and the sixth copper layer. Wherein, the first hard board protective layer is arranged adjacent to the fourth copper layer, the fifth copper layer is made on the first hard board layer, the second hard board protective layer is made on the surface of the fifth copper layer, and the second hard board protection layer is formed on the surface of the fifth copper layer. A sixth copper layer is made on the surface of the layer.

In this embodiment, by arranging the first copper layer on which the connector pads are formed and the third copper layer on which the component pads are formed on the same surface, the connector pads and the component pads are on the same copper layer. layer, so that the component pads and connector pads are brushed once, avoiding the process of brushing the pads of the battery protection board multiple times.

This embodiment also provides another method for fabricating a battery protection circuit board, as shown in FIG. 4 , which is a schematic flowchart of another embodiment of the method for fabricating a battery protection circuit board of the present application. Specifically include:

Step S41 : providing a flexible substrate, and forming a first copper layer and a second copper layer on the opposite sides of the flexible substrate respectively.

Wherein, the flexible substrate, the first copper layer and the second copper layer together constitute a battery protection flexible board. In this embodiment, a hard board protective layer is formed on the surface of the battery protection soft board, so that the soft board becomes a hard board. In this embodiment, a hard board protective layer is selected to be made on the copper surface of one side of the battery protection soft board, so that the battery protection hard board forms an asymmetric structure,

Step S42 : forming a first hard board protective layer on the surface of the second copper layer, and performing slit processing at predetermined positions of the first hard board protective layer to form a hard board area with a hard board protective layer and no hard board protection layer of the flex board area.

In step S42, the first hard board protective layer is a fluidized adhesive layer, which is formed on the surface of the second copper layer by means of coating and photo-development. A slit is made at a predetermined position of the first hard board protective layer, and the first hard board protective layer is torn off to one side along the predetermined position to form a hard board protective area with a hard board protective layer and a hard board protective layer without a hard board protective layer. the soft board area.

In this embodiment, a third copper layer can also be formed on the surface of the first hard board protective layer, and a second hard board protective layer can be formed on the surface of the third copper layer to further protect the battery protection circuit board in the hard board area. The material of the hard board protective layer is polystyrene colloid. In this embodiment, a fourth copper layer may also be formed on the surface of the second hard board protective layer.

In this embodiment, a soft board protective layer can also be made on the surface of the second copper layer in the soft board area, the thickness of the soft board protective layer is thinner than that of the first hard board protective layer, and the soft board protective layer includes soft board glue layer and the soft board film layer, the soft board glue layer and the soft board film layer overlap with the first hard board glue layer.

Step S43 : forming connector pads on the soft board area on the surface of the first copper layer, and forming component pads on the hard board area on the first copper layer.

Step S44 : brushing tin on the first copper layer once.

The beneficial effect of this embodiment is: by making a hard board protective layer on one side of the flexible substrate, the battery protection circuit board has asymmetric hard board area and soft board area, and by making components on the surface of the first copper layer on the same side Pads and connector pads, and brush tin on the connector pads and component pads on the surface of the ground and copper layer, thus saving the need for the connector pads connected to the mobile phone and the component pads connected to the battery. The process of brushing tin twice. And the battery protection circuit board formed by the battery protection circuit board provided in this embodiment has the characteristics of a soft board and a hard board at the same time.

The above descriptions are only the embodiments of the present application, and are not intended to limit the scope of patent protection of the present application. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present application, or directly or indirectly applied to other related The technical field is similarly included in the scope of patent protection of this application.

Claims

A battery protection circuit board, characterized in that the battery protection circuit board comprises a battery protection hard board and a battery protection soft board,

The battery protection hard board is connected with the battery protection soft board through a flexible substrate;

The battery protection soft board includes a first copper layer and a second copper layer located on opposite sides of the flexible substrate;

The battery protection hard board includes a third copper layer and a fourth copper layer located on opposite sides of the flexible substrate, and a hard board protection layer located on the other side of the fourth copper layer relative to the flexible substrate;

The first copper layer and the third copper layer are arranged on the same side of the flexible substrate, wherein a connector pad is arranged on the first copper layer, and a component is arranged on the third copper layer pad.
The battery protection circuit board according to claim 1, wherein,

The second copper layer of the battery protection soft board and the fourth copper layer of the battery protection hard board are arranged on the same side of the flexible substrate.
The battery protection circuit board according to claim 2, wherein,

The first copper layer and the third copper layer have the same thickness, and the second copper layer and the fourth copper layer have the same thickness.
The battery protection circuit board according to claim 1, wherein,

The battery protection soft board further includes a soft board protective layer, the soft board protective layer is located on the side of the second copper layer away from the flexible substrate, and the soft board protective layer includes a thermosetting adhesive layer and a reinforcing layer. film layer;
The battery protection circuit board according to claim 4, wherein,

The soft board protective layer includes a thermosetting adhesive layer and a reinforcing film layer.
The battery protection circuit board according to claim 4, wherein,

The battery protection soft board further includes at least one via hole, and the via hole in the soft board region penetrates the first copper layer, the flexible substrate and the second copper layer.
The battery protection circuit board according to claim 1, wherein,

The battery protection hard board includes a hard board protection layer, and the hard board protection layer is located on one side of the fourth copper layer away from the flexible substrate.
The battery protection circuit board according to claim 1, wherein,

The hard board protective layer includes a first hard board protective layer, a second hard board protective layer,

The first hard board protective layer is located on the other side of the fourth copper layer relative to the flexible substrate; the second hard board protective layer includes a fifth copper layer and a sixth copper layer on opposite sides, on the other side of the first hard board protective layer opposite to the fourth copper layer.
The battery protection circuit board according to claim 7, wherein,

The battery protection hard board further includes at least one via hole, and the via hole in the hard board region penetrates through the third copper layer to the sixth copper layer, and the third copper layer to the sixth copper layer The flexible substrate, the fourth copper layer, the first hard board protective layer, the fifth copper layer, and the second hard board protective layer are included between the layers.
The battery protection circuit board according to claim 4 or claim 7, wherein the thickness of the soft board protection layer of the battery protection soft board is smaller than the thickness of the hard board protection layer of the battery protection hard board.
A manufacturing method of a battery protection circuit board, characterized in that:

Provide battery protection hard board and battery protection soft board;

A first copper layer and a second copper layer are formed on the opposite sides of the battery protection soft board, and a third copper layer and a fourth copper layer are formed on the opposite sides of the battery protection hard board;

The battery protection soft board and the battery protection hard board are butt-assembled, so that the first copper layer and the third copper layer are arranged on the same layer.
The method for manufacturing a battery protection circuit board according to claim 11, wherein:

A connector pad is fabricated on the first copper layer, a component pad is fabricated on the third copper layer, and the connector pad and the component pad are once brushed with tin.
The method for manufacturing a battery protection circuit board according to claim 12, wherein:

After brushing tin on the connector pads and the component pads once, the method further includes: disposing a green oil protection layer on the surface of the tin layer.
The method for manufacturing a battery protection circuit board according to claim 11, wherein the battery protection soft board and the battery protection hard board are butt-assembled, so that the first copper layer is connected to the battery protection hard board. The step of disposing the third copper layer on the same layer includes:

The second copper layer and the fourth copper layer are butt-assembled.
The manufacturing method of the battery protection circuit board according to claim 11, wherein the manufacturing method of the battery protection circuit board further comprises:

A soft board protective layer is formed on the surface of the second copper layer away from the first copper layer; the soft board protective layer includes a thermosetting adhesive layer and a reinforcing film layer.
The method for manufacturing a battery protection circuit board according to claim 15, wherein:

A via hole is formed in the battery protection soft board region, and the via hole in the soft board region penetrates the first copper layer, the flexible substrate and the second copper layer.
The manufacturing method of the battery protection circuit board according to claim 11, wherein the manufacturing method of the battery protection circuit board further comprises:

A hard board protective layer is formed on the surface of the fourth copper layer away from the third copper layer, the hard board protective layer at least includes a first hard board protective layer and a second hard board protective layer and a fifth copper layer and a sixth copper layer.
The method for fabricating a battery protection circuit board according to claim 17, wherein the step of fabricating a hard board protection layer on the surface of the fourth copper layer away from the third copper layer comprises:

A first hard board protective layer, a fifth copper layer, a second hard board protective layer and a sixth copper layer are sequentially formed on the surface of the fourth copper layer.
The method for manufacturing a battery protection circuit board according to claim 18, wherein:

A via hole is formed in the hard board area of the battery protection, and the via hole in the hard board area passes through the third copper layer to the sixth copper layer, and the third copper layer to the sixth copper layer The flexible substrate, the fourth copper layer, the first hard board protective layer, the fifth copper layer, and the second hard board protective layer are included in between.
The method for manufacturing a battery protection circuit board according to claim 11, wherein:

The first copper layer and the third copper layer have the same thickness, and the second copper layer and the fourth copper layer have the same thickness.