CN113078324B

CN113078324B - Method for manufacturing bipolar battery, bipolar plate and unipolar plate thereof

Info

Publication number: CN113078324B
Application number: CN202011195672.4A
Authority: CN
Inventors: 郭晓锋; 张才勇
Original assignee: Yidewei Energy Technology Jiangsu Co ltd
Current assignee: Yidewei Energy Technology Jiangsu Co ltd
Priority date: 2020-01-03
Filing date: 2020-10-30
Publication date: 2022-12-13
Anticipated expiration: 2040-10-30
Also published as: CN213042923U; WO2021136015A1; CN113078324A; WO2021136013A1; CN113078325A

Abstract

The present application provides a method of manufacturing a bipolar battery and bipolar and unipolar plates thereof. One of the methods of manufacturing a bipolar plate for a bipolar battery includes the steps of: prefabricating a plurality of metal wires; arranging a plurality of metal wires in an injection mold to be used as injection molding inserts; performing injection molding in an injection mold to form a current collector, wherein the formed current collector comprises a plurality of metal wires, a plurality of cross rods formed in a plastic cavity and a frame, and the current collector comprises a first section and a second section which are separated by a separation sealing part; after the injection molding is finished, jacking the current collector and enabling the current collector to leave the injection mold; and wrapping or coating the negative electrode active substance and the positive electrode active substance on the first section and the second section of the current collector respectively, thereby forming the negative electrode plate and the positive electrode plate respectively. The method has the advantages of simple process, high efficiency, low cost and suitability for large-scale production, and the bipolar plate manufactured by the method is suitable for forming a large-capacity battery.

Description

Method for manufacturing bipolar battery, bipolar plate and unipolar plate thereof

Technical Field

The present application relates to a method of manufacturing a battery, and more particularly, to a method of manufacturing a bipolar battery, and a bipolar plate and a unipolar plate thereof.

Background

In the modern society, batteries are widely applied to various fields, such as electronic watches, and electric automobiles, and the batteries are required to be used for power supply. Although the various types of batteries vary greatly in size, the internal structure is very similar. Generally, a battery includes a case, an electrode plate (also referred to as a pole piece) disposed inside the case, an electrolyte, and a tab, a tab paste, and the like located outside the case. Batteries can be classified into a winding type battery in which a pole piece is disposed inside a battery case in a winding manner and a stacking type battery in which a pole piece is disposed inside a battery case in a stacking/stacking manner, depending on the arrangement of the pole piece inside the battery.

In a stacked battery, a plurality of battery cells (also referred to as battery cells) each including a positive electrode plate, a negative electrode plate, and a separator therebetween are generally included. The same-polarity polar plates in the single lattices (namely the battery monomers) are connected in parallel, and the battery capacity is determined by the size, the parallel connection quantity and the like of the polar plates; the positive and negative poles of the adjacent battery cells are connected in series, and the total voltage of the battery is determined by the number of the battery cells connected in series. The electrode plate is composed of a current collector and an active material thereon. For example, the positive electrode plate is formed by coating a positive electrode active material on a current collector, and the negative electrode plate is formed by coating a negative electrode active material on a current collector.

The stack type battery may be classified into a unipolar battery and a bipolar battery according to whether positive and negative electrode plates of the battery share a current collector. In a unipolar battery, the current collectors of the positive and negative electrode plates are separate, that is, the current collectors of the positive and negative electrode plates are two separate parts. The positive and negative plates of one single cell and the positive and negative plates of the other single cell in the unipolar battery are isolated from each other, and must be connected in series by additional welding, so that the process is complex and the reliability is poor. In the bipolar battery, the positive and negative plates share the same current collector, and the positive and negative plates sharing the same current collector are respectively located in different battery units. Therefore, it realizes the series connection between different battery cells by means of the current collectors without additional welding. Compared with a unipolar battery, the bipolar battery is more convenient and reliable to realize series connection.

However, conventionally, a metal plate is generally used as a current collector in the manufacture of a bipolar battery, and positive and negative electrode active materials are applied to both the front and back surfaces of the metal plate current collector to form a positive electrode plate and a negative electrode plate (the whole of which is a bipolar plate). The anode and the cathode of the bipolar plate are separated by the current collector and are positioned in two adjacent battery monomers, and the current collector plays a role of connecting the two adjacent battery monomers in series. The bipolar battery manufactured by this method is not suitable for a large-capacity battery due to its structural limitation (each unit battery has only one positive electrode plate and one negative electrode plate). In addition, the method has more complex manufacturing process and lower efficiency, and is not suitable for large-scale production.

Disclosure of Invention

One of the technical problems to be solved by the present application is to overcome the above-mentioned deficiencies in the prior art, and to provide at least one method for manufacturing a bipolar plate of a bipolar battery, which is simple in process, high in efficiency, low in cost, and suitable for mass production, and the bipolar plate manufactured by the method is suitable for forming a large-capacity battery.

Another object of the present invention is to provide a method for manufacturing at least one unipolar plate (including a positive unipolar plate and a negative unipolar plate) of a bipolar battery, which is similar to the above-described method, and thus is also simple in process, efficient, low in cost, suitable for mass production, and the unipolar plate manufactured according to the method is suitable for forming a large-capacity battery.

A further object of the present invention is to provide at least one method for producing a bipolar battery, which is suitable for producing a bipolar battery using bipolar plates and unipolar plates (i.e., positive unipolar plates and negative unipolar plates) produced by the method of the present application. According to the method, the battery with large capacity can be manufactured, the process is simple (the series connection of different battery monomers is not required to be realized by welding), the manufactured battery has good quality, the phenomena of liquid leakage, liquid channeling and the like can be effectively prevented, and the service life is long.

Meanwhile, the application also provides the bipolar plate of the bipolar battery, the unipolar plate and the bipolar battery manufactured according to the method.

The technical solution adopted in the present application is specifically described below. Before the technical solutions are explained in detail, the inventive concepts of the present application are briefly explained as follows:

in short, the current collector with a plate-shaped structure of the bipolar battery in the prior art is replaced by the current collector with a plate-shaped structure formed by metal wires, plastic transverse ribs and frames, and the current collector with the plate-shaped structure is formed in an injection molding mode. That is, a plurality of metal wires are prefabricated and arranged in parallel in a mold as an injection insert, and the mold has cavities in different directions (for example, perpendicular to the metal wires) from the metal wires and cavities at the periphery, and the plastic in these cavities can form non-metal rods (i.e., plastic transverse ribs) (hereinafter referred to as "transverse rods") and frames during injection molding. After injection molding, the cross bars and the frames are fixed together with the metal wires to form a grid-shaped current collector. The injection molding mode has simple process and convenient manufacture and is suitable for batch production. It should be noted that the focus of the present application is to provide the concept of the manufacturing method, and the specific mold structure can be designed by those skilled in the art according to actual needs, so that the present application is not described in detail.

After forming a grid-shaped current collector, wrapping or coating a negative electrode active substance and a positive electrode active substance at two ends of the current collector so as to respectively form a negative plate and a positive plate of the bipolar plate; or the current collector is integrally wrapped or coated with a negative electrode active substance or a positive electrode active substance, so that a negative monopolar plate or a positive monopolar plate is formed.

In the process of manufacturing the battery, the negative single-pole plate, the positive single-pole plate and the corresponding bipolar plate are selected and stacked according to a certain rule (see details below), so that the positive plate and the negative plate of each bipolar plate are respectively positioned in different battery cells, and the series connection among different battery cells can be directly realized. Also, a plurality of such plate stacks (separated by separators) may be included within each cell. Thus, the capacity of the battery can be greatly expanded.

Method for producing bipolar plates for bipolar batteries

According to the present application, a method of manufacturing a bipolar plate for a bipolar battery is provided, comprising the steps of:

(a) Prefabricating a plurality of metal wires;

(b) Arranging the plurality of metal wires in a substantially parallel, spaced apart relationship and with a portion thereof in an injection mold as an injection insert, the plurality of metal wires extending in a first direction, the injection mold having therein a plastic cavity extending in a second direction different from the first direction and a plastic cavity at a periphery;

(c) And performing injection molding in an injection mold to form a current collector, wherein the formed current collector comprises the part of the plurality of metal wires, which is positioned in the injection mold, a plurality of cross rods and a frame, which are formed in the plastic cavity. The plurality of cross bars extend along the second direction so as to intersect with the plurality of metal wires and be fixed together; and wherein along the first direction, the current collector comprises a first segment and a second segment separated by a separation seal;

(d) After the injection molding is finished, jacking the current collector and moving the current collector by a fixed step length so as to draw the next part of the plurality of metal wires into the injection mold;

(e) Repeating steps (c) and (d) to produce a plurality of said current collectors connected together;

(f) Separating a plurality of the current collectors connected together; and

(g) And respectively wrapping or coating a negative electrode active substance and a positive electrode active substance on the first section and the second section of each current collector so as to respectively form a negative plate and a positive plate.

In the above method, the length of the wire prepared in step (a) may be several times, several tens of times, several hundreds of times or even several thousands of times the length of the final bipolar plate, and the specific length can be determined by the specific needs of those skilled in the art. The length of the wire thus enables continuous injection moulding as described in step (d). It is understood that such continuous injection molding can greatly improve the efficiency of the injection molding operation.

Then, in step (f), the plurality of sequentially connected current collectors are separated into a plurality of individual current collectors by cutting. The specific cutting tool and cutting method may be known in the art (e.g., a cutting machine that can be used to cut metal, etc.). In step (g), the negative electrode active material and the positive electrode active material may be coated or coated on the current collector by methods known in the art, which are not described herein.

Another method of fabricating a bipolar plate for a bipolar battery according to the present application includes the steps of:

A. prefabricating a plurality of metal wires;

B. disposing the plurality of metal wires substantially in parallel and spaced apart from one another in an injection mold as an injection insert, the plurality of metal wires extending in a first direction, the injection mold having therein a plastic cavity extending in a second direction different from the first direction and a plastic cavity at a periphery;

C. performing injection molding in an injection mold to form a current collector, wherein the formed current collector comprises the plurality of metal wires, a plurality of cross rods formed in the plastic cavity and a frame, and the plurality of cross rods extend along a second direction so as to intersect with the plurality of metal wires and be fixed together; and wherein along the first direction, the current collector comprises a first segment and a second segment separated by a separation seal;

D. after the injection molding is finished, jacking the current collector and enabling the current collector to leave the injection mold; and

E. wrapping or coating a negative electrode active material and a positive electrode active material on the first segment and the second segment of the current collector, respectively, to constitute a negative electrode plate and a positive electrode plate, respectively.

In contrast to the above-described method, in this method the wire is cut to a length suitable for forming the bipolar plate prior to injection molding. That is, the plurality of wires prefabricated in step a have a length suitable for constituting the bipolar plate, and the subsequent steps of cutting and separating the current collector are omitted. Accordingly, the current collector of each bipolar plate is formed separately. This method is also simple.

In both of the above methods, preferably, the separation seal portion includes two sealing stages spaced apart from each other. These sealing lands are also formed during the injection molding process.

In the subsequent manufacture of the cell, after the bipolar plate is mounted to the cell casing and the cell top cover is closed, the two sealing lands are pressed to form two sealing walls. The sealing wall is connected with the inner wall of the battery jar in the battery shell in a sealing way, a glue injection groove is formed between two adjacent sealing walls, and the glue injection groove is communicated with a glue groove positioned between the battery top cover and the inner wall of the battery jar, so that resin glue can be injected through the glue groove. The structure can effectively realize the sealing between the adjacent battery monomers and prevent the liquid leakage or gas leakage between the adjacent battery monomers. If necessary, three or more sealing lands may be formed even more, thereby more effectively ensuring complete sealing between the adjacent battery cells.

In each bipolar plate formed by the method, two ends of the plurality of metal wires exceed the frame to form a first exceeding part adjacent to the first section and a second exceeding part adjacent to the second section, wherein the first exceeding part is provided with a first end sealing part, and the second exceeding part is provided with a second end sealing part. These seals can be formed directly during the injection molding process.

As an example of the present application, the bipolar plate is formed as a first bipolar plate in which the first end seal includes only one seal land and the second end seal includes two seal lands spaced apart from each other.

As another example of the present application, the bipolar plate is formed as a second bipolar plate in which the first end seal includes two seal lands spaced apart from each other and the second end seal includes only one seal land.

As yet another embodiment of the present application, the bipolar plate formed is a third bipolar plate in which the first end seal includes only one seal land and the second end seal also includes only one seal land.

As yet another embodiment of the present application, the bipolar plate formed is a fourth bipolar plate in which the first end seal includes two seal lands spaced apart from each other and the second end seal also includes two seal lands spaced apart from each other. Such a bipolar plate can effectively achieve sealing at both ends thereof.

Method for producing a unipolar plate of a bipolar battery

According to the present application, there is provided a method of manufacturing a unipolar plate of a bipolar battery, similar to the first method of manufacturing a bipolar plate of a bipolar battery described above, including the steps of:

(a) Prefabricating a plurality of metal wires;

(b) Arranging the plurality of metal wires in a substantially parallel, spaced apart manner and with a portion thereof located in an injection mold as an injection insert, the plurality of metal wires extending in a first direction, the injection mold having therein a plastic cavity extending in a second direction different from the first direction and a plastic cavity located at a periphery;

(c) Performing injection molding in an injection mold to form a current collector, wherein the formed current collector comprises a part of the plurality of metal wires in the injection mold, a plurality of cross bars formed in the plastic cavity and a frame, and the plurality of cross bars extend along the second direction so as to intersect with the plurality of metal wires and be fixed together;

(f) Separating a plurality of said current collectors joined together; and

(g) And coating or coating a negative electrode active substance or a positive electrode active substance on each current collector to form a negative unipolar plate or a positive unipolar plate.

On each formed current collector, two ends of the multiple metal wires exceed the frame to form a first exceeding part and a second exceeding part, wherein a first end sealing part is formed on the first exceeding part, and a second end sealing part is formed on the second exceeding part; and wherein one of the first end seal and the second end seal comprises one seal land and the other spaced apart two seal lands; the plurality of wires extend from the first end seal or the second end seal including the two seal stages for conducting electrical current.

In this method, the length of the metal wire prefabricated in the step (a) may be several times, several tens of times, several hundreds of times or even several thousands of times of the length of the final unipolar plate, and the specific length may be determined by those skilled in the art according to specific needs. Such wire lengths enable continuous injection molding as described in step (d). The continuous injection molding can greatly improve the efficiency of injection molding operation.

According to another method of manufacturing a unipolar plate of a bipolar battery provided by the present application, similarly to the second method of manufacturing a bipolar plate of a bipolar battery described above, specifically, it includes the steps of:

A. prefabricating a plurality of metal wires;

C. performing injection molding in an injection mold to form a current collector, wherein the formed current collector comprises the plurality of metal wires, a plurality of cross rods formed in the plastic cavity and a frame, and the plurality of cross rods extend along a second direction so as to intersect with the plurality of metal wires and be fixed together;

E. the current collector is respectively wrapped or coated with a negative electrode active substance or a positive electrode active substance to form a negative unipolar plate or a positive unipolar plate,

the two ends of the multiple metal wires exceed the frame to form a first exceeding part and a second exceeding part, a first end sealing part is formed on the first exceeding part, and a second end sealing part is formed on the second exceeding part; and wherein, one of the first end seal and the second end seal comprises one seal land, the other spaced apart two seal lands; the plurality of wires extend from the first end seal or the second end seal including the two seal stages for conducting electrical current. The first and second seal portions may each be formed during an injection molding process.

Unlike the above-described methods, this method cuts the wire to a length suitable for forming the unipolar plates prior to injection molding. That is, the plurality of wires prepared in step a have a length suitable for forming the unipolar plate, and the subsequent steps of cutting and separating the current collector are omitted. Accordingly, each unipolar plate is formed separately. This method is also simple.

In the above embodiment, the length of the excess portion (i.e., the exposed wire) of the wire of the positive unipolar plate or the negative unipolar plate beyond the first end seal or the second end seal is 3 to 10mm for cast-welding to the bus bar.

Preferably, in the unipolar plate and the bipolar plate formed according to the above-described method, each of the two spaced-apart sealing lands has a width in the first direction of 2 to 20mm and a gap therebetween of 0.5 to 5mm; wherein said gap can be used for filling with resin glue, thereby effectively achieving sealing. Each of the sealing stages extends in the second direction and is formed with elastic through-holes near both ends thereof. The resilient through-hole may be formed together during the injection molding process. The elastic through hole can improve the sealing contact capacity between the sealing platform and the battery jar.

In the above method, the material for injection molding may be any one of ABS, PP, PVC, PE, PS, PBT, PTFE, PET and RPET, and may also be any one of silicone rubber, ethylene propylene diene monomer, butadiene rubber, styrene butadiene rubber, isoprene rubber, fluororubber, or EPE or EPP or EPVC or EVA or EPS or EPER or EPU or EUF or EPF foamed material, or any one of foamed ethylene propylene diene monomer rubber, foamed styrene butadiene rubber, foamed chloroprene rubber or foamed silicone rubber.

Preferably, in a third direction perpendicular to the first and second directions, the sealing station has a top and a bottom, the top extending 0.2-3 mm beyond the top of the rim to accommodate the membrane when assembled; the bottom is 0.05-1 mm lower than the bottom of the frame to accommodate the coated paper. When assembled, the sealing platform can be compressed by 0.05-3 mm to form a sealing wall.

In the above embodiments, the cross section of the metal wire and the cross bar (also called plastic cross bar) can be round, prismatic or square. When designing the die cavity, the design can be carried out according to the shapes and the sizes of the cross sections of the metal wires and the cross bars.

In the above embodiment, the distance between the plurality of wires is 2-20mm, and the distance between the plurality of cross bars is 2-30mm. The first direction and the second direction may be perpendicular to each other or may form an angle. In a preferred embodiment of the present application, the first direction and the second direction are perpendicular to each other.

In the above embodiment, in the shaped current collector, the wire passes through the cross bar (for example, a cross rib made of plastic) whose thickness is greater than the dimension of the wire in the third direction by 0.05 to 2mm and whose bottom is lower than the bottom of the frame by 0.01 to 2mm, so as to fix the wire.

Method for manufacturing bipolar battery

According to the method for manufacturing the bipolar battery provided by the application, the method can be used for manufacturing the bipolar battery comprising two or more battery units. The details are as follows.

According to a first method of manufacturing a bipolar battery, a bipolar battery including two battery cells is manufactured. The method comprises the following steps:

(1) Providing a shell, a first battery cell and a second battery cell, wherein the shell is provided with a through groove for accommodating the first battery cell and the second battery cell, and the first battery cell and the second battery cell are fixed into a whole and are electrically connected with each other;

(2) Installing the first battery cell and the second battery cell in the through groove of the shell, and sealing the shell; and

(3) And injecting electrolyte into the through groove.

The first and second battery cells comprise a positive single-pole plate, a negative single-pole plate and a fourth bipolar plate manufactured by the method of the application; wherein the fourth bipolar plate comprises a positive plate and a negative plate; and wherein the negative plate and the positive monopolar plate of the fourth bipolar plate are contained in a first cell and the positive plate and the negative monopolar plate of the fourth bipolar plate are contained in a second cell.

It should be noted that only the plate configuration of one cell (including the positive electrode, the negative electrode and the separator therebetween) within each battery cell is described herein. In an actual battery product, there are many such battery cells within each battery cell. That is, the battery includes a plurality of positive unipolar plates, a plurality of negative unipolar plates, and a plurality of fourth bipolar plates. In the first battery unit, a plurality of positive single polar plates, a plurality of negative polar plates of a fourth bipolar plate and a diaphragm positioned between the positive single polar plates and the negative polar plates are arranged; in the second cell, there are a plurality of positive plates of the fourth bipolar plate, a plurality of negative unipolar plates, and a separator therebetween. Because of this, the battery is suitable for a large-capacity battery, while the battery is small in volume and lateral dimension.

According to a second method of manufacturing a bipolar battery provided by the present application, a bipolar battery including three battery cells is manufactured. The method comprises the following steps:

(1) Providing a shell and a first battery monomer, a second battery monomer and a third battery monomer, wherein the shell is internally provided with a through groove for accommodating the first battery monomer, the second battery monomer and the third battery monomer which are fixed into a whole and are electrically connected in sequence;

(2) Installing the first, second and third battery cells in the through groove of the shell, and sealing the shell; and

(3) And injecting an electrolyte into the through groove.

The first, second and third battery cells include a positive monopolar plate, a negative monopolar plate, a first bipolar plate and a second bipolar plate manufactured by the method of the present application;

the first bipolar plate comprises a positive plate and a negative plate, and the second bipolar plate comprises a positive plate and a negative plate; and is provided with

Wherein the positive single electrode plate and the negative electrode plate of the second double electrode plate are included in a first battery cell; the positive plate of the second bipolar plate and the negative plate of the first bipolar plate are contained in a second battery cell; the positive plate and the negative unipolar plate of the first bipolar plate are included in a third battery cell.

Also, only the plate configuration of one cell (including the positive and negative electrodes and the separator therebetween) within each cell is described herein. In an actual battery product, there are many such battery cells within each battery cell. That is, the battery includes a plurality of positive unipolar plates, a plurality of negative unipolar plates, a plurality of first bipolar plates, and a plurality of second bipolar plates. In the first battery unit, a plurality of positive single-pole plates, a plurality of negative plates of the second double-pole plate and a diaphragm positioned between the positive single-pole plates and the negative plates of the second double-pole plate are arranged; the second battery unit is internally provided with a plurality of positive plates of the second double-pole plate, negative plates of the first double-pole plate and a diaphragm positioned between the positive plates and the negative plates; within the third cell there is a plurality of positive plates of the first bipolar plate, negative unipolar plates and a separator therebetween. Because of this, the battery is suitably made into a large-capacity battery.

According to a third method of manufacturing a bipolar battery provided by the present application, it is used to manufacture a bipolar battery including four battery cells. The method comprises the following steps:

(1) Providing a shell and a first battery cell, a second battery cell, a third battery cell and a fourth battery cell, wherein the shell is internally provided with a through groove for accommodating the first battery cell, the second battery cell, the third battery cell and the fourth battery cell, and the first battery cell, the second battery cell, the third battery cell and the fourth battery cell are fixed into a whole and are electrically connected in sequence;

(2) Installing the first, second, third and fourth battery cells in the through groove of the shell, and sealing the shell; and

(3) And injecting electrolyte into the through groove.

Wherein the first, second, third and fourth cells comprise a positive monopolar plate, a negative monopolar plate, a first bipolar plate, a second bipolar plate and a third bipolar plate manufactured according to the method of the present application;

the first bipolar plate comprises a positive plate and a negative plate, the second bipolar plate comprises a positive plate and a negative plate, and the third bipolar plate comprises a positive plate and a negative plate; and is

Wherein the positive single electrode plate and the negative electrode plate of the second double electrode plate are included in a first battery cell; the positive plate of the second bipolar plate and the negative plate of the third bipolar plate are contained in a second cell; the positive plate of the third bipolar plate and the negative plate of the first bipolar plate are contained in a third cell; the positive plate and the negative plate of the first bipolar plate are contained in a fourth battery cell.

Also, only the plate configuration of one cell (including the positive and negative electrodes and the separator therebetween) within each cell is described herein. In a practical battery product, there are many such battery cells within each cell. That is, the battery includes a plurality of positive unipolar plates, a plurality of negative unipolar plates, a plurality of first bipolar plates, a plurality of second bipolar plates, and a plurality of third bipolar plates. In the first battery unit, a plurality of positive single-pole plates, a plurality of negative plates of the second double-pole plate and a diaphragm positioned between the positive single-pole plates and the negative plates of the second double-pole plate are arranged; the second battery unit is internally provided with a plurality of positive plates of a second bipolar plate, a plurality of negative plates of a third bipolar plate and a diaphragm positioned between the positive plates and the negative plates; in the third cell unit, a plurality of positive plates of the third bipolar plate, a plurality of negative plates of the first bipolar plate and a diaphragm positioned between the positive plates and the negative plates; the fourth battery cell has a positive electrode plate including a plurality of the first bipolar plates, a negative electrode plate including a plurality of the negative unipolar plates, and a separator interposed therebetween.

According to a fourth method of manufacturing a bipolar battery provided by the present application, it is used to manufacture a bipolar battery including four or more (i.e., at least five) battery cells. The method comprises the following steps:

(1) Providing a shell and N battery monomers which are fixed into a whole and electrically connected in sequence, wherein N is greater than 4, and a through groove for accommodating the N battery monomers is formed in the shell;

(2) Installing the N battery monomers in the through groove of the shell, and sealing the shell; and

(3) And injecting an electrolyte into the through groove (10').

The N battery cells comprise a positive single-pole plate, a negative single-pole plate, a first bipolar plate, a second bipolar plate and a third bipolar plate which are manufactured according to the method;

Wherein the positive single electrode plate and the negative electrode plate of the second double electrode plate are included in a first battery cell; the positive plate of the second bipolar plate and the negative plate of the first of the third bipolar plates are contained in a second cell; the positive plate of the first said third bipolar plate and the negative plate of the second third bipolar plate are contained in a third cell, arranged in this way \8230; the positive plate of the (N-2) th third bipolar plate and the negative plate of the first bipolar plate are contained in the (N-1) th cell; the positive plate and the negative unipolar plate of the first bipolar plate are included in the nth battery cell. Namely, the middle battery cell adopts the third bipolar plate, and the battery cells at two sides adopt the first bipolar plate and the second bipolar plate.

That is, for a battery including more than four battery cells, the plate types of the first and second cells in the order number are identical to the plate types of the first and second cells of the four battery cells, the plate types of the first and second cells in the order number are also identical to the plate types of the first and second cells in the order number, and the plate types of the first and second cells in the order number are all third bipolar plates.

Also, only the plate configuration of one cell (including the positive electrode, the negative electrode, and the separator therebetween) within each cell is described herein. In an actual battery product, there are many such battery cells in each battery cell. That is, the battery includes a plurality of positive unipolar plates, a plurality of negative unipolar plates, a plurality of first bipolar plates, a plurality of second bipolar plates, and a plurality of third bipolar plates. In the first battery unit, a plurality of positive single-pole plates, a plurality of negative plates of the second double-pole plate and a diaphragm positioned between the positive single-pole plates and the negative plates of the second double-pole plate are arranged; the second battery unit is internally provided with a plurality of positive plates of a second bipolar plate, a plurality of negative plates of a third bipolar plate and a diaphragm positioned between the positive plates and the negative plates; in a third battery cell, the battery comprises a plurality of positive plates of the first third bipolar plate, a plurality of negative plates of the second third bipolar plate and separators located between the positive plates and the negative plates of the second third bipolar plate, wherein the separators are 8230; the (N-1) th battery cell comprises a plurality of positive plates of the (N-2) th third bipolar plates, a negative plate of the first bipolar plate and a diaphragm positioned between the positive plates and the negative plate; the nth battery cell includes a plurality of positive plates of the first bipolar plate, a plurality of negative unipolar plates, and a separator interposed therebetween.

As can be seen from the above description, when manufacturing bipolar batteries including different numbers of battery cells, the corresponding bipolar plates and positive and negative single plates are selected according to the above rules and arranged according to the rules. For how to mount and fix the bipolar plate, the positive and negative single plates and the diaphragm to constitute the battery cells (and make the electrical connection between the battery cells (realized by the wires inside the bipolar plate, as described above)), see the related contents described in the patent application CN 202011043045.9. The skilled person can also carry out this according to his knowledge. The other steps of manufacturing the above batteries are basically the same, except that the arrangement rules of the bipolar plates and the positive and negative single plates thereof are different due to the different number of the single batteries. Also, the structure of the case of these batteries is similar from the viewpoint of the structure of the battery that is constructed. Therefore, the structure common to these batteries is described below. Of course, the sizes of the battery case and the battery top cover may also vary according to the number of the battery cells. This is not the focus of the invention and is therefore not described in detail.

In the above method for manufacturing a battery provided in the present application, the step includes mounting a battery top cover on the top of the case, and sealing the battery top cover with the case.

In an embodiment of the present application, it is preferable that the housing has a substantially U-shaped cross section, and includes two opposite parallel side walls and a bottom wall connecting the two side walls and the bottom wall, the two side walls and the bottom wall defining the through groove, and an opening formed at the top. The housing may also be formed by injection molding.

In each of the above embodiments, the battery further comprises a battery top cover. Preferably, in the step (2), the battery top cover is fixed in the opening of the shell in an elastic clamping manner. For example, two parallel grooves are formed on two side walls of the shell close to the top, the battery further comprises two wedge-shaped strips which can be inserted into the grooves, and two sides of the battery top cover are provided with inverses matched with the two wedge-shaped strips, so that the battery top cover is fixed in the opening and self-locking is realized through the matching of the wedge-shaped strips and the inverses.

In the method for manufacturing the battery provided by the application, each sealing platform is elastically deformed under the pressure of the battery top cover, so that the sealing walls of each battery monomer are formed, and a glue injection groove is formed between every two adjacent sealing walls.

In each of the above-described cells provided by the present application, the housing is generally U-shaped in cross section and includes two opposing parallel side walls and a bottom wall connecting the two, the side walls and the bottom wall defining the through slot and forming an opening at the top.

As an embodiment of the present application, two parallel grooves are formed on two side walls of the housing near the top, and tenons that can be inserted into the grooves are formed on two sides of the battery top cover, so that the battery top cover is fixed in the opening by means of the cooperation of the tenons and the grooves and self-locking is realized. Particularly, when the installation during the battery top cap, through applying external force, make the battery top cap push down polar plate and diaphragm together, when setting for the position, release external force, the sealed platform of diaphragm and polar plate is bounce-back, and the tenon of battery top cap gets into in the recess of casing and realizes the auto-lock to guarantee that the polar plate is under pressure state all the time. After the battery jar is locked with the battery cover, a U-shaped groove is formed and is communicated with the glue injection groove, a three-dimensional glue wall is formed after glue injection, each monomer forms an independent closed space, and short-circuit discharge caused by electrolyte or gas communication due to unreliable sealing among single cells (battery monomers) is effectively prevented.

As another embodiment of the present application, two parallel grooves are formed on two side walls of the housing near the top, the battery further comprises two wedge-shaped strips which can be inserted into the grooves, and two mating recesses are formed on two sides of the battery top cover, so that the battery top cover is fixed in the opening and self-locking is realized by means of the mating of the wedge-shaped strips and the recesses. The battery top cover of this structure is mounted in a similar manner to the above-described embodiment, and thus self-locking is achieved in a similar manner. Particularly, when the installation during the battery top cap, through applying external force, make the battery top cap push down polar plate and diaphragm together, when arriving the settlement position, release external force, the sealed platform of diaphragm and polar plate is bounce-back, and the back-off of battery top cap gets into the wedge block and the auto-lock of battery jar to guarantee that the polar plate is in under the pressure state all the time. This approach is more convenient to process than the above embodiments.

In the above embodiment, each sealing platform is elastically deformed under the pressure of the battery top cover, so as to form the sealing walls of each single battery, and a glue injection groove is formed between two adjacent sealing walls for injecting resin glue, so that a good sealing effect is achieved.

According to the method for manufacturing the bipolar plate of the bipolar battery, compared with the prior art, the method has the following advantages that:

(1) The grid-shaped current collector is adopted, the grid-shaped current collector is formed by injection molding, then the positive plate and the negative plate are respectively formed at the two ends of the current collector, and the middle part of the current collector is separated by the separation sealing part, so that the method has the advantages of simple process, high efficiency, low cost and suitability for large-scale production, and the manufactured bipolar plate is suitable for forming a large-capacity battery.

(2) Because the manufactured bipolar plate is provided with the separation sealing part between the positive plate and the negative plate, when the bipolar plate is used for forming a battery, the sealing between adjacent battery monomers can be realized, the phenomena of liquid channeling and gas channeling between different battery monomers are prevented, and the service life of the battery is prolonged.

(3) When the bipolar plate manufactured by the method is used for forming a battery, the positive plate and the negative plate are respectively arranged in different battery monomers, so that the electric connection between the adjacent battery monomers is directly realized through the metal wire, processes such as welding and the like are omitted, the manufacturing is convenient, and the method is suitable for batch production.

The method for manufacturing a unipolar plate of a bipolar battery according to the present application has similar technical effects to those of the above-described method for manufacturing a bipolar plate of a bipolar battery with respect to the prior art.

The method of manufacturing a bipolar battery provided herein is suitable for manufacturing a bipolar battery using bipolar plates and unipolar plates (i.e., positive unipolar plates and negative unipolar plates) manufactured according to the method of the present application. Such batteries using plates of grid-like current collectors can be constructed with many stacks within each cell, and are therefore suitable for making large capacity batteries. And because the steps of realizing series connection and the like through welding are omitted, the process is simpler, the production cost is saved, the manufactured battery has good sealing performance, short-circuit discharge caused by electrolyte or gas series connection due to unreliable sealing can be effectively prevented, the phenomena of liquid leakage, liquid channeling and the like are effectively avoided, and the service life of the battery is prolonged.

Drawings

In order to more clearly illustrate the embodiments of the present application and the advantageous technical effects thereof, the following detailed description of the embodiments of the present application is made with reference to the accompanying drawings.

FIG. 1A is a schematic top view of a current collector of a plate of a bipolar battery fabricated according to the method of the present application;

fig. 1B isbase:Sub>A sectional view taken alongbase:Sub>A-base:Sub>A in fig. 1, illustratingbase:Sub>A cross-sectional structure of the current collector;

FIG. 2A is a top view of one plate (first bipolar plate: one seal at the negative plate end (left) and two seals at the positive plate end (right)) of a bipolar battery manufactured according to the method of the present application, the bipolar plate being formed on the basis of the current collectors shown in FIGS. 1A and 1B;

fig. 2B isbase:Sub>A sectional view taken alongbase:Sub>A-base:Sub>A in fig. 2A, showingbase:Sub>A structure ofbase:Sub>A cross section of the first bipolar plate;

FIG. 3A is a top view of another bipolar battery plate made according to the method of the present application (second bipolar plate: two seals are provided at the negative plate end (left side) and one seal is provided at the positive plate end (right side));

fig. 3B isbase:Sub>A sectional view taken alongbase:Sub>A-base:Sub>A in fig. 3A, showingbase:Sub>A structure ofbase:Sub>A cross section of the second bipolar plate;

FIG. 4A is a top view of yet another plate of a bipolar battery made according to the method of the present application (a third bipolar plate having a seal land at both the negative plate end (left side) and the positive plate end (right side));

fig. 4B isbase:Sub>A sectional view taken alongbase:Sub>A-base:Sub>A in fig. 4A, showing the structure ofbase:Sub>A cross section ofbase:Sub>A third bipolar plate;

FIG. 5A is a top view of yet another plate of a bipolar battery made according to the method of the present application (a fourth bipolar plate where both the negative plate end (left side) and the positive plate end (right side) are provided with two seal lands);

figure 5B isbase:Sub>A cross-sectional view taken alongbase:Sub>A-base:Sub>A in figure 5A showing the configuration ofbase:Sub>A cross-section ofbase:Sub>A fourth bipolar plate;

FIG. 6A is a top view of a positive bipolar plate of a bipolar battery made according to the method of the present application;

fig. 6B isbase:Sub>A sectional view taken alongbase:Sub>A-base:Sub>A in fig. 6A, showingbase:Sub>A structure ofbase:Sub>A cross section of the positive monopolar plate;

fig. 7A is a top view of a negative unipolar plate of a bipolar battery fabricated in accordance with the methods of the present application;

fig. 7B isbase:Sub>A sectional view taken alongbase:Sub>A-base:Sub>A in fig. 7A, showing the structure of the cross-section of the negative unipolar plate;

FIG. 8 is a schematic perspective view of one embodiment of a battery made according to the method of the present application;

fig. 9 is a top view of the battery shown in fig. 8, showing the structure of the top of the battery;

fig. 10 is an enlarged sectional view taken alongbase:Sub>A-base:Sub>A in fig. 9, showing the longitudinal internal structure of the battery asbase:Sub>A whole;

fig. 11 is an enlarged sectional view taken along B-B in fig. 10, showing the internal structure of one cell of the battery;

fig. 12A is a schematic front view of each cell in the embodiment (four cells) shown in fig. 8, illustrating the connection of the positive and negative unipolar plates to the three bipolar plates;

fig. 12B is a schematic top view of each battery cell in the embodiment (four battery cells) shown in fig. 8;

fig. 13A and 13B are schematic front and top views of three single cells in an embodiment similar to fig. 12A and 12B; and

fig. 14A and 14B are similar to fig. 12A and 12B, and are schematic front and top views of each of two battery cells in an embodiment.

Description of reference numerals:

1-wire, 2-cross-bar, 3-current collector, 31-first section of current collector 31, 32-second section of current collector, 4-frame, 5-separation seal, 51, 52-seal table; 5' -a first end seal; 5 "-second end seal; 51', 52', 51", 52" -seal land, 6-positive active, 7-positive monopolar plate, 8-negative active, 9-negative monopolar plate, 11-first bipolar plate, 12-second bipolar plate, 13-third bipolar plate, 14-fourth bipolar plate; 111. 121, 131-positive plate; 112. 122, 132-negative plate;

10-shell, 10' -through groove (battery groove), 15-diaphragm, 17-busbar, 20-battery top cover, 30-battery end cover 22-air escape valve, 23-glue groove, 24-liquid injection hole, 25-glue injection groove, 26-wedge-shaped strip, 27-inverted buckle, 28-spacing rib, 29-cover plate, 40-polarity color scale, 31-electrolyte plug, 53-elastic through hole, A-1 st monomer, B-2 nd monomer, C-3 rd monomer and D-4 th monomer; 100-positive terminal, 200-negative terminal.

Detailed Description

Embodiments of the present application are described in detail below with reference to the accompanying drawings. Various aspects of the present application may be more readily understood by reading the following description of the specific embodiments with reference to the accompanying drawings. It should be noted that these examples are merely exemplary, which are only used for explaining and illustrating the technical solutions of the present application, and do not limit the present application. On the basis of these examples, a person skilled in the art may make various modifications and changes, and all the technical solutions obtained by equivalent changes are included in the scope of protection of the present application.

In general, the invention of the present application includes three aspects: (1) a method of manufacturing a bipolar plate for a bipolar battery; (2) A method of manufacturing a unipolar plate (including a positive unipolar plate and a negative unipolar plate) of a bipolar battery; and (3) a method for manufacturing a bipolar battery comprising the bipolar plate and the unipolar plate. The embodiment of the present invention will be specifically described below in three aspects.

Incidentally, since the present application focuses on a method of manufacturing a bipolar battery, and a bipolar plate and a unipolar plate thereof, rather than specific structures of the bipolar battery, the bipolar plate, and the unipolar plate, specific structures of these products are not necessarily described in detail. The specific structure of the bipolar battery, bipolar plate and unipolar plate can be found in the disclosure of CN 202010353387.4.

1Method for manufacturing bipolar plate of bipolar battery

As described above, the present application is conceived to replace a current collector having a plate-like structure of a bipolar battery in the related art with a current collector having a grid-like structure, and to form the current collector having the grid-like structure by injection molding. During injection molding, a plurality of metal wires are adopted as injection molding inserts and are arranged in a mold in parallel. The methods of manufacturing bipolar plates (and unipolar plates) for bipolar batteries can be divided into two types, depending on whether the wire is cut before or after injection molding: namely cutting the metal wire before injection molding and cutting the metal wire after injection molding. The following description is made separately.

According to a first embodiment of a method (cut wire after injection) for manufacturing a bipolar plate for a bipolar battery provided by the present application, the method comprises the steps of:

(a) A plurality of wires 1 are prefabricated.

(b) The plurality of metal wires 1 are arranged substantially in parallel and spaced apart from each other (see fig. 1A) and a part thereof is located in an injection mold (not shown) as an injection insert, the plurality of metal wires 1 extend in a first direction X (i.e., a direction in which electrons flow in a battery product), and the injection mold has therein a plastic cavity extending in a second direction Y different from the first direction X and a plastic cavity located at the periphery (not shown, but the cavity may be designed as needed by those skilled in the art).

(c) Performing injection molding in an injection mold to form a current collector 3 (the injection molding process is common knowledge in the art and is not described herein), where the formed current collector 3 includes a portion of the multiple metal wires 1 located in the injection mold, multiple cross bars 2 formed in a plastic cavity, and a frame 4 (as shown in fig. 1A and 1B). As shown in fig. 1, a plurality of cross bars 2 extend in the second direction Y so as to intersect the plurality of wires 1 and be fixed together; and wherein, along said first direction X, said current collector 3 comprises a first segment 31 and a second segment 32, both separated by a separation seal 5.

(d) After the injection molding is completed, the current collector 3 is jacked up and moved by a fixed step length, so that the next part of the plurality of metal wires 1 is pulled into the injection mold. The step of jacking and moving the current collector may be performed by conventional techniques in the art (e.g., by a robot), and will not be described herein.

(e) Repeating steps (c) and (d) to produce a plurality of said current collectors 3 connected together.

(f) Separating a plurality of said current collectors 3 connected together, an

(g) The first section 31 and the second section 32 of each current collector 3 are respectively wrapped or coated with a negative electrode active material 8 and a positive electrode active material 6, thereby respectively constituting a negative electrode plate and a positive electrode plate. Therefore, the positive electrode plate and the negative electrode plate are formed on the same current collector 3, and are connected in series by a plurality of wires 1, and a separation seal 5 is provided between the wires 1.

In the above step (a), the material, the sectional shape and the size (sectional size and length) of the wire 1 may be selected and set as required by those skilled in the art. For example, for nickel-metal hydride batteries, a nickel material may be selected; for lead acid batteries, lead-tin alloys may be used. The cross-sectional shape of the metal wire can be circular, prismatic and other geometric shapes. The length of the wires may be several times, tens of times, hundreds of times or even thousands of times the length of the final bipolar plate, as determined by the particular needs of those skilled in the art.

The advantage of this method described above is that it enables continuous injection moulding of the current collector as described in step (d). The continuous injection molding can greatly improve the efficiency of injection molding operation, but relatively speaking, the requirement on the automation degree of processing equipment is higher (to realize a series of steps of injection molding, jacking, moving and the like).

According to a second embodiment of another method (cutting the wire before injection molding) for manufacturing a bipolar plate for a bipolar battery provided by the present application, the method comprises the steps of:

A. a plurality of wires 1 are prefabricated such that said wires 1 have a length suitable for constituting a bipolar plate (as shown in fig. 1A, 1B).

B. Arranging the plurality of metal wires 1 in an injection mold in a substantially parallel manner and spaced from each other to form an injection insert, wherein the plurality of metal wires 1 extend along a first direction X, and the injection mold is provided with a plastic cavity extending along a second direction Y different from the first direction X and a plastic cavity (not shown, but the plastic cavity can be designed by the skilled in the art according to needs);

C. performing injection molding in an injection mold to form a current collector 3, wherein the formed current collector 3 comprises the plurality of metal wires 1, a plurality of cross bars 2 formed in the plastic cavity, and a frame 4, and the plurality of cross bars 2 extend along a second direction Y so as to intersect with the plurality of metal wires 1 and be fixed together; and as shown in fig. 1A, 1B, along said first direction X, said current collector 3 comprises a first section 31 and a second section 32, which are separated by a separation seal 5;

D. after the injection molding is finished, jacking up the current collector 3 and enabling the current collector to leave the injection mold; and

E. a negative electrode active material 8 and a positive electrode active material 6 are wrapped or coated on the first segment 31 and the second segment 32 of the current collector, respectively, thereby constituting a negative electrode plate and a positive electrode plate, respectively. Therefore, the positive electrode plate and the negative electrode plate are formed on the same current collector 3, and are connected in series by a plurality of wires 1, and a separation seal portion 5 is provided in a portion where the wires 1 are located.

Unlike the first embodiment, in the second embodiment, the wire is cut into a length suitable for forming the bipolar plate before injection molding, and the subsequent steps of cutting and separating the current collectors, i.e., the current collectors of each bipolar plate are separately formed, are omitted, thereby providing simplicity.

Preferably, referring to fig. 1A, 1B, in the current collector 3 formed in the above two embodiments, the separation seal 5 includes two sealing

lands

51, 52 spaced apart from each other. These sealing lands are also formed during the injection molding process. As shown in fig. 1A and 1B, two ends of the plurality of wires 1 of the current collector 3 exceed the frame 4 to form a first exceeding portion 101 adjacent to the first segment 31 and a second exceeding portion 102 adjacent to the second segment 32, wherein the first exceeding portion 101 is provided with a first end sealing portion 5', and the second exceeding portion 102 is provided with a second end sealing portion 5 ″.

The bipolar plates manufactured according to the method of the present application have four types in total, depending on the number of sealing lands comprised by the first end seal 5' and the second end seal 5 "of the bipolar plate to be formed, as described in detail below.

In one embodiment, the bipolar plate manufactured according to the method of the present application is the first bipolar plate 11. Referring to fig. 2A, 2B, in the first bipolar plate 11, the first end seal 5 'includes only one seal land 51', and the second end seal 5 ″ includes two seal lands 51', 52' spaced apart from each other.

In another embodiment, the bipolar plate manufactured according to the method of the present application is the second bipolar plate 12. Referring to fig. 3A, 3B, in the second bipolar plate 12, the first end seal 5' includes two sealing lands 51', 52' spaced apart from each other, and the second end seal 5 ″ includes only one sealing land 51".

In yet another embodiment, the bipolar plate manufactured according to the method of the present application is a third bipolar plate 13. Referring to fig. 4A, 4B, in the second bipolar plate 13, the first end seal 5 'includes only one seal land 51', and the second end seal 5 ″ also includes only one seal land 51 ″.

In yet another embodiment, the bipolar plate manufactured according to the method of the present application is a fourth bipolar plate 14. Referring to fig. 5A, 5B, in the fourth bipolar plate 14, the first end seal 5' includes two lands 51', 52' spaced apart from one another, and the second end seal 5 "also includes two lands 51", 52 "spaced apart from one another. Namely, the positive plate end and the negative plate end are both provided with two sealing platforms. The structure can effectively realize the sealing between the single battery where the bipolar plate is positioned and the adjacent single battery or the battery edge, and achieve good sealing effect. The second bipolar plate 14 is suitable for use as a plate of a battery including only two cells.

Briefly, structurally, a bipolar plate for a bipolar battery manufactured according to the method of the present application includes a grid-mounted current collector 3 (a composite current collector, including both wire and plastic) as shown in fig. 1A, 1B, positive and negative active materials 6, 8 (see fig. 2A, 2b, 3a, 3b, 4a, 4B) disposed on the current collector 3, a separation seal 5 disposed between the positive and negative

active materials

6, 8, and first and second end seals 5', 5 "disposed at outer ends of the positive and negative active materials. But features of the present application include the following:

(1) The current collector 3 which simultaneously comprises the metal wire 1, the plastic cross rod 2 and the plastic frame 4 is formed in an injection molding mode, and the current collector is a composite current collector.

(2) The current collector 3 is formed with a partition seal 5 at the middle portion and first and second end seal lands 5', 5 ″ at both ends.

Although the negative plate and the positive plate of the bipolar plate share the same current collector, when the bipolar plate is assembled into a battery, the positive plate and the negative plate belong to two adjacent battery cells, and the metal wire 1 without an active substance in the middle realizes the series connection (namely, the electrical connection) of the two cells, so that the bipolar plate bears the electronic conduction between the two cells and does not need additional welding. In the prior art, the serial connection of the monomers needs to weld the positive electrode leading-out end welded into a whole by the previous monomer and the negative electrode leading-out end welded into a whole by the next monomer, so that the process is complex and the reliability is low.

In addition, as described above, the partition seal portion 5 includes the two seal stages 51, 52 spaced apart from each other. After the bipolar plate is mounted to the cell housing and the cell top cover is closed, the two sealing

lands

51, 52 are pressed to form two sealing walls. The sealing wall is connected with the inner wall of the battery jar in the battery shell in a sealing way, the glue injection groove 25 is formed between the two

adjacent sealing walls

51 and 52, the glue injection groove 25 is communicated with the glue groove 23 (namely, the U-shaped groove formed after the battery jar is locked with the battery top cover) between the battery top cover and the inner wall of the battery jar, and therefore resin glue can be injected into the glue groove 23. After glue is poured, a three-dimensional glue wall (namely a sealing wall) is formed, and each monomer forms an independent closed space. The structure can effectively realize the sealing between the adjacent battery monomers and prevent the liquid leakage or gas leakage between the adjacent battery monomers. If necessary, three or more sealing lands may be formed even more, thereby more effectively ensuring complete sealing between adjacent battery cells.

2Method for manufacturing monopolar plate of bipolar battery

Structurally, the unipolar plates (including the positive and negative unipolar plates) fabricated according to the method of fabricating a unipolar plate of a bipolar battery provided herein are similar to the bipolar plates fabricated according to the above-described method. In contrast, only one type of active material (i.e., the positive electrode active material and the negative electrode active material) is provided on the metal wire 1 on the unipolar plate, and accordingly, only both ends thereof are provided with the sealing portions. Therefore, the method for manufacturing the unipolar plate of the bipolar battery is also similar to the method for manufacturing the bipolar plate described above. See below for details.

According to a third embodiment of a method (injection molding and cutting of the wire) for manufacturing a unipolar plate of a bipolar battery provided by the present application, similar to the first embodiment described above, the method includes the steps of:

(a) Prefabricating a plurality of metal wires 1;

(b) Arranging the plurality of metal wires 1 substantially in parallel, spaced apart from each other (i.e., in a manner similar to that shown in fig. 1A) and having a portion thereof as an injection insert in an injection mold, the plurality of metal wires 1 extending in a first direction (e.g., X-direction in fig. 1A), the injection mold having therein a plastic cavity extending in a second direction (e.g., Y-direction in fig. 1A) different from the first direction and a plastic cavity at the periphery;

(c) Performing injection molding in an injection mold to form a current collector 3, wherein the formed current collector 3 comprises a part of the plurality of metal wires 1 in the injection mold, a plurality of cross bars 2 formed in the plastic cavity, and a frame 3, and the plurality of cross bars 2 extend along the second direction Y so as to intersect with the plurality of metal wires 1 and be fixed together;

(d) After the injection molding is finished, jacking the current collector 3 and moving the current collector by a fixed step length so as to draw the next part of the plurality of metal wires 1 into the injection mold;

(e) Repeating steps (c) and (d) to produce a plurality of said current collectors 3 connected together;

(f) Separating a plurality of said current collectors 3 connected together; and

(g) A negative electrode active material 8 or a positive electrode active material 6 is wrapped or coated on each of the current collectors 3, thereby constituting a negative monopolar plate 9 or a positive monopolar plate 7 (see fig. 6A, 6B, 7A, 7B).

Wherein, on each formed current collector 3, both ends of the plurality of wires 1 exceed the frame 4 to form a first excess portion on which a first end sealing portion 5 'is formed and a second excess portion on which a second end sealing portion 5' is formed (see fig. 6A, 6B, 7A, 7B). And wherein one of said first end seal 5' and said second end seal 5 "comprises one sealing land, the other spaced apart two sealing lands; the plurality of wires 1 extend from the first end seal 5' or the second end seal 5 "comprising two sealing stations for conducting electrical current.

For example, in the embodiment shown in fig. 6A, 6B, the first end seal 5' includes two spaced-apart sealing lands 51', 52', and the second end seal 5 "includes one sealing land; a plurality of wires 1 extend from said first end seal 5' comprising two sealing stations. Although fig. 6A, 6B show the positive electrode plate 7, the negative electrode plate 9 may have such a structure. As another example, in the embodiment shown in fig. 7A, 7B, the first end seal 5' includes one land, while the second end seal 5 "includes two spaced lands 51", 52"; a plurality of wires 1 extend from said second end seal 5 "comprising two sealing stations. Also, although fig. 7A and 7B show the negative electrode plate 9, the positive electrode plate 7 may have such a structure.

Similar to the above-described method of manufacturing a bipolar plate, in the above-described step (a), with respect to the material, the sectional shape, and the size (sectional size and length) of the wire 1, those skilled in the art can select and set them as needed. For example, for nickel-metal hydride batteries, nickel materials may be selected; for lead acid batteries, lead-tin alloys may be used. The cross-sectional shape of the metal wire can be round, prismatic, square and other geometric shapes. The length of the wires may be several times, tens of times, hundreds of times or even thousands of times the length of the final bipolar plate, as determined by the specific needs of the skilled person. This method has the advantage of enabling continuous injection molding of the current collector, as described in step (d). The continuous injection molding can greatly improve the efficiency of injection molding operation, but relatively speaking, the requirement on the automation degree of processing equipment is higher (to realize a series of steps of injection molding, jacking, moving and the like). Then, in step (f), the plurality of sequentially connected current collectors are separated into a plurality of individual current collectors by cutting. The specific cutting tool and cutting method may be known in the art (e.g., a cutting machine that can be used to cut metal, etc.). In step (g), the negative electrode active material or the positive electrode active material may be coated or coated on the current collector by methods known in the art, which are not described herein.

According to a fourth embodiment of another method (cutting the wires before injection molding) for manufacturing a unipolar plate of a bipolar battery provided by the present application, similarly to the second embodiment described above, specifically, it includes the steps of:

A. prefabricating a plurality of metal wires 1;

B. arranging the plurality of metal wires 1 in an injection mold in a substantially parallel manner and spaced apart from each other as an injection insert, the plurality of metal wires 1 extending in a first direction (for example, X direction in fig. 1A), the injection mold having therein a plastic cavity extending in a second direction (for example, Y direction in fig. 1A) different from the first direction and a plastic cavity at a periphery;

C. performing injection molding in an injection mold to form a current collector 3, wherein the formed current collector 3 comprises the plurality of metal wires 1, a plurality of cross bars 2 formed in the plastic mold cavity, and a frame 4 (see fig. 6A and 6B), and the plurality of cross bars 2 extend along a second direction so as to intersect with the plurality of metal wires 1 and be fixed together;

D. after the injection molding is finished, jacking the current collector 3 and enabling the current collector to leave the injection mold; and

E. and a negative electrode active material 8 or a positive electrode active material 6 is respectively coated or coated on the current collector 3, so that a negative monopolar plate 9 or a positive monopolar plate 7 is formed.

The unipolar plate manufactured in the fourth embodiment is the same as the unipolar plate manufactured in the third embodiment, in which both ends of the plurality of wires 1 exceed the frame 4 to form a first excess portion on which the first end sealing part 5' is formed and a second excess portion on which the second end sealing part 5 ″ is formed. And wherein one of said first end seal 5' and said second end seal 5 "comprises one sealing land, the other spaced apart two sealing lands; the plurality of wires 1 extend from the first end seal 5' or the second end seal 5 "comprising two sealing stations for conducting electrical current.

For example, in the embodiment shown in fig. 6A, 6B, the first end seal 5' includes two spaced-apart lands 51', 52', and the second end seal 5 "includes one land; a plurality of wires 1 extend from said first end seal 5' comprising two sealing stations. Although fig. 6A, 6B show the positive electrode plate 7, the negative electrode plate 9 may have such a structure. As another example, in the embodiment shown in fig. 7A, 7B, the first end seal 5' includes one land, while the second end seal 5 "includes two spaced lands 51", 52"; a plurality of wires 1 extend from said second end seal 5 "comprising two sealing stations. Also, although fig. 7A and 7B show the negative electrode plate 9, the positive electrode plate 7 may have such a structure.

The fourth embodiment differs from the third embodiment in that the method cuts the wire to a length suitable for forming the unipolar plates prior to injection molding. That is, the plurality of wires prepared in step a have a length suitable for forming the unipolar plate, and the subsequent steps of cutting and separating the current collector are omitted. Accordingly, each unipolar plate is formed separately. This method is also simple.

Preferably, in the bipolar plate and the unipolar plate manufactured according to the above-described method, as shown in fig. 1A, 1B, the distance d1 between the plurality of wires 1 is 2 to 20mm; the distance d2 between the cross rods 2 is 2-30mm; and the first direction X and the second direction Y are substantially perpendicular to each other. I.e. the wires 1 and the cross bar 2 are perpendicular to each other. The current collectors with such a structure and size range facilitate the design and production of the mold.

In the bipolar and unipolar plates manufactured according to the above-described method, as shown in fig. 1A, 1B, each of the two spaced-apart sealing lands (e.g., 51, 52', 51', 52';51", 52") has a width in the first direction X of 2 to 10mm and a gap therebetween of 0.5 to 5mm; wherein the gap is used for filling with resin glue, thereby achieving better sealing. Furthermore, in the above-described embodiment, as shown in fig. 1A, 2A, 3A, 4A, 5A, each of the sealing tables extends in the second direction Y, and is formed with the elastic through-holes 53 near both ends thereof, and the elastic through-holes 53 may be directly formed during the injection molding process, which may be achieved by designing the corresponding mold cores. The elastic through-hole 53 can improve the sealing contact capability between the sealing stage 5 and the battery can 10'.

As shown in fig. 1B, 2B, 3B, 4B, 5B, in a third direction Z perpendicular to the first direction X and the second direction Y, the sealing stages 51, 52;51', 52';51", 52" have a top and a bottom, the top extending 0.5-3 mm beyond the top of the frame 4 to accommodate the membrane when assembled; the bottom is 0.05-1 mm lower than the bottom of the frame to accommodate the coated paper. When assembled, the sealing platform can be compressed by 0.05-3 mm to form a sealing wall.

In the above embodiment, the cross-section of the cross-bar 2 may also be circular, prismatic or square, and the wire 1 passes through the cross-bar 2. The thickness of the cross bar is 0.05-2 mm larger than the dimension of the metal wire 1 along the third direction, and the bottom of the cross bar is 0.01-2 mm lower than the bottom of the frame, so that the metal wire 1 is fixed.

Of course, it is also possible that both of the first end seal 5' and the second end seal 5 "comprise two spaced sealing lands (i.e. similar to the structure shown in fig. 2A, 2B, not shown), for example for a battery with only one cell, such positive and negative unipolar plates could be used.

3Method for manufacturing bipolar battery

The method for manufacturing the bipolar battery can be used for manufacturing the bipolar battery comprising two or more than two battery units. For ease of understanding, before specifically describing the method of manufacturing the battery, the structure of the battery manufactured (taking a battery having four battery cells as an example) will be described first.

Referring to fig. 8, a schematic perspective view of a battery having four battery cells manufactured according to a method of the present application is shown. As shown in the drawing, the battery includes a case 10, a battery top cover 20 positioned on the top of the case 10, battery end caps 30 positioned at both ends of the case 10, and electrode plates, separators, electrolytes, etc. positioned in the case 10. Wherein the electrode plates are the positive monopolar plate 7, the negative monopolar plate 9, and one or more of the first bipolar plate 11, the second bipolar plate 12, the third bipolar plate 13, and the fourth bipolar plate 14 manufactured by the method of the present application as described above.

Referring to fig. 9 to 11, a through groove (also referred to as a battery groove) 10' is formed in the case 10 for accommodating a plurality of battery cells. In this embodiment, four battery cells a, B, C and D are included, so the through groove 10' is a battery groove capable of accommodating four battery cells. Accordingly, three sets of partition ribs may be formed in the through groove 10 'of the case, so as to partition the through groove 10' into four partitions (each partition may accommodate one battery cell), and one battery cell is disposed in each partition. Bus bars 17 (see fig. 10) are provided at both ends of the battery container 10', one ends of the bus bars 17 are electrically connected to the exposed wires 1 of the positive and negative unipolar plates 7 and 9, respectively, and the other ends of the bus bars 17 are electrically connected to a positive terminal 100 and a negative terminal 200 (see fig. 10), respectively.

As shown in fig. 11, the housing 10 is generally U-shaped in cross section and includes two opposing

parallel side walls

103, 104 and a bottom wall 104 connecting the two, the two side walls 101, 102 and the bottom wall 103 defining a through slot 10' and forming an opening at the top. The battery top cover 20 is a generally flat plate-like structure that is secured in an opening of the housing 10 by a snap-fit connection (described in more detail below). Two cell end caps 30 are fixed to both end portions of the case 10, respectively.

Referring to fig. 9 to 10, the positive terminal 100 and the negative terminal 200 are respectively provided at both ends of the battery. Each battery monomer is arranged on the battery top cover 20 correspondingly, each monomer is provided with an air release valve 22, the upper part of each air release valve 22 is provided with a cover plate 29, and a rubber groove 23 is arranged between the two sides of the battery top cover 19 in the Y direction and the inner wall of the battery groove 10'. The bottom of the battery jar 10' is provided with a plurality of electrolyte injection holes 24 corresponding to each battery monomer. One side of the battery container 10' is provided with an electrolyte stopper 31. The inner side of the bottom of the battery container 10' and the top of the battery monomer are respectively provided with a layer of diaphragm 15. The two ends of each battery monomer are respectively formed into sealing walls at the two ends by a plurality of upper and lower laminated sealing tables 5, the sealing walls are connected with the inner wall of the through groove 10 'in a sealing manner, a glue injection groove 25 is formed between every two adjacent sealing walls, the glue injection groove 25 is communicated with a glue groove 23 positioned between the battery top cover 20 and the inner wall of the battery groove 10', and therefore resin glue can be injected through the glue groove 23. The structure can effectively realize the sealing between the adjacent battery monomers and prevent the liquid leakage or gas leakage between the adjacent battery monomers.

As previously described, the battery top cover 200 is fixed in the opening 104 of the case 10 by means of elastic snap-fitting. Specifically, referring to fig. 11, as an elastic clamping manner, two

parallel grooves

1031, 1041 are provided at positions close to the top of the two side walls 102, 103 of the housing 10, the battery further includes two wedge-shaped strips 26 that can be inserted into the

grooves

1031, 1041, and the two sides of the battery top cover 200 are provided with the inverse buckles 27 that the two wedge-shaped strips 26 cooperate with each other, so that the battery top cover 200 is fixed in the opening 104 by means of the cooperation of the wedge-shaped strips 26 and the inverse buckles 27 and is self-locked.

It is understood by those skilled in the art that the elastic clamping can be realized in other manners, for example, a tenon can be formed on both sides of the battery top cover 200 and can be inserted into the

grooves

1031, 1041, so that the battery top cover 200 can be fixed in the opening 104 and self-locked by the cooperation of the tenon and the

grooves

1031, 1041.

In the above embodiments, each sealing platform is elastically deformed under the pressure of the top cover 200, so as to form the sealing walls of each battery cell, and the glue injection groove 25 is formed between two adjacent sealing walls. As described above, the glue injection groove 25 is communicated with the glue groove 23 between the battery top cover and the inner wall of the battery groove, so that resin glue can be injected through the glue groove, sealing between adjacent battery cells is effectively achieved, and liquid leakage or gas leakage between the adjacent battery cells is prevented.

For the bipolar battery including four battery cells as described above, the bipolar battery can be manufactured as follows. The method comprises the following steps:

(1) Providing a shell 10 and first, second, third and fourth battery monomers A, B, C and D, wherein the shell 10 is provided with a through groove 10' for accommodating the first, second, third and fourth battery monomers A, B, C and D, and the first, second, third and fourth battery monomers A, B, C and D are fixed into a whole and are electrically connected in sequence;

(2) Installing the first, second, third and fourth battery cells a, B, C and D in the through groove 10' of the housing 10, and sealing the housing 10; and

(3) Electrolyte is injected into the through groove 10'.

The first, second, third and fourth battery cells a, B, C and D include the positive monopolar plate 7, the negative monopolar plate 9, the first bipolar plate 11, the second bipolar plate 12 and the third bipolar plate 13 manufactured by the method of the present application. Referring to fig. 12A and 12B, the first bipolar plate 11 includes a positive plate 111 and a negative plate 112, the second bipolar plate 12 includes a positive plate 121 and a negative plate 122, and the third bipolar plate 13 includes a positive plate 131 and a negative plate 132.

In the specific arrangement (stacking) of the bipolar plate and the positive and negative unipolar plates, see fig. 12A, 12B, such that the negative plates 122 of the positive and second bipolar plates 7, 12 are contained in the first cell a (with a separator disposed therebetween, the same applies below); the positive plate 121 of the second bipolar plate 12 and the negative plate 132 of the third bipolar plate 13 are included in the second cell B; the positive plate 131 of the third bipolar plate 13 and the negative plate 112 of the first bipolar plate 11 are included in a third cell C; the positive electrode plate 111 of the first bipolar plate 11 and the negative monopolar plate 9 are included in the third battery cell D. For clarity, fig. 12A, 12B show only one positive bipolar plate 7, one first bipolar plate 11, one second bipolar plate 12, one third bipolar plate 13, and the negative bipolar plate 9 to illustrate the positional relationship therebetween.

In fact, as shown in fig. 10 and 11, a plurality of the above-mentioned plates may be contained in each battery cell. That is, the battery may include a plurality of positive unipolar plates 7, a plurality of negative unipolar plates 9, a plurality of first bipolar plates 11, a plurality of second bipolar plates 12, and a plurality of third bipolar plates 13. In the first battery cell a, there are a plurality of positive electrode plates 7, a plurality of negative electrode plates 122 of the second bipolar plate 12, and a separator located therebetween; in the second cell B, there are a plurality of positive plates 121 of the second bipolar plate 12, negative plates 132 of the third bipolar plate 13, and separators therebetween; in the third unit cell C, there are a plurality of positive electrode plates 131 of the third bipolar plate 13, a plurality of negative electrode plates 112 of the first bipolar plate 11, and a separator interposed therebetween; the fourth battery cell D includes a positive electrode plate 111 including a plurality of first bipolar plates 11, a plurality of negative monopolar plates 9, and a separator interposed therebetween. Such a structure contributes to the enlargement of the capacity of the battery, and therefore the battery is suitable for a large capacity battery.

Wherein the step (2) includes installing the battery top cap 20 on the top of the case 10 and sealing the battery top cap 20 with the case 10. As mentioned above, the housing 10 is substantially U-shaped in cross section and comprises two opposite

parallel side walls

103, 104 and a bottom wall 105 connecting the two, the two

side walls

103, 104 and the bottom wall 105 defining the through slot 10' and forming an opening at the top. In the step 2, the battery top cover 20 is fixed in the opening of the housing 10 by an elastic clamping manner, and the clamping structure is as described above.

According to another method of manufacturing a bipolar battery provided herein, a battery including three battery cells is manufactured. The method comprises the following steps:

(1) Providing a shell 10 and first, second and third battery monomers A, B and C, wherein the shell 10 is provided with a through groove 10' for accommodating the first, second and third battery monomers A, B and C, and the first, second and third battery monomers A, B and C are fixed into a whole and are electrically connected in sequence;

(2) Mounting the first, second and third battery cells a, B and C in the through groove 10' of the housing 10, and sealing the housing 10; and

(3) Electrolyte is injected into the through groove 10'.

The first, second and third battery cells a, B and C include the positive and negative unipolar plates manufactured by the above method of the present application, and the first and second bipolar plates 11 and 12. The first bipolar plate 11 includes a positive plate 111 and a negative plate 112, and the second bipolar plate 12 includes a positive plate 121 and a negative plate 122.

As shown in fig. 13A, 13B, when the bipolar plate and the positive and negative unipolar plates are specifically arranged (stacked), the following are caused: the positive and negative electrode plates 7 and 122 of the second bipolar plate 12 are included in the first cell a; the positive electrode plate 121 of the second bipolar plate 12 and the negative electrode plate 112 of the first bipolar plate 11 are included in the second battery cell B; the positive electrode plate 111 and the negative electrode plate 9 of the first bipolar plate 11 are included in the third battery cell C. Also, for clarity, only one positive unipolar plate 7, one first bipolar plate 11, one second bipolar plate 12, one negative unipolar plate 9 are shown in fig. 13A, 13B to illustrate the positional relationship therebetween.

In a practical battery product, a plurality of the above-described electrode plates may be included in each battery cell. That is, the battery may include a plurality of positive unipolar plates 7, a plurality of negative unipolar plates 9, a plurality of first bipolar plates 11, and a plurality of second bipolar plates 12. In the first battery cell a, there are a plurality of positive single-electrode plates 7, a plurality of negative electrode plates 122 of the second double-electrode plate, and a separator located therebetween; in the second battery cell B, there are a plurality of positive electrode plates 121 of the second bipolar plate 12, negative electrode plates 112 of the first bipolar plate 11, and separators located therebetween; the third battery cell C includes a positive electrode plate 111 including a plurality of first bipolar plates 11, a plurality of negative monopolar plates 9, and a separator interposed therebetween. Such a structure helps to enlarge the capacity of the battery without making the battery bulky. Also, the step (2) includes mounting the battery top cover 20 on the top of the case 10, and the specific operation is the same as the step (2) in the above method.

According to another method of manufacturing a bipolar battery provided by the present application, a bipolar battery including two battery cells is manufactured. The method comprises the following steps:

(1) Providing a shell 10 and a first battery monomer A and a second battery monomer B, wherein the shell 10 is provided with a through groove 10' for accommodating the first battery monomer A and the second battery monomer B, and the first battery monomer A and the second battery monomer B are fixed into a whole and are electrically connected with each other;

(2) Installing the first and second battery cells a and B in the through groove 10' of the housing 10, and sealing the housing 10; and

(3) Electrolyte is injected into the through groove 10'.

Wherein, the first and the second battery units A and B comprise a positive single polar plate 7, a negative single polar plate 9 and a fourth bipolar plate 14 which are manufactured according to the method of the application; wherein the fourth bipolar plate 14 includes a positive plate 141 and a negative plate 142.

Referring to fig. 14A, 14B, when the bipolar plate and the positive and negative unipolar plates are specifically arranged (stacked), such that: the negative plate 142 and the positive plate 7 of the fourth bipolar plate 14 are included in the first cell a; the negative monopolar plate 9 and the positive plate 141 of the fourth bipolar plate 14 are included in the second cell B. Also, for the sake of clarity, only one positive unipolar plate 7, one fourth bipolar plate 14, and one negative unipolar plate 9 are shown in fig. 14A, 14B to illustrate the positional relationship therebetween.

In a practical battery product, a plurality of the above-described electrode plates may be included in each battery cell. That is, the cell may include a plurality of positive unipolar plates 7, a plurality of negative unipolar plates 9, and a plurality of fourth bipolar plates 14. In the first battery cell a, there are a plurality of positive single polar plates 7, a plurality of negative polar plates 142 of the fourth bipolar plate 14 and a diaphragm located therebetween; in the second cell B, there are a plurality of positive plates 141 of the fourth bipolar plate 14, a plurality of negative unipolar plates 9, and a separator therebetween. The battery with the structure can enlarge the capacity of the battery without excessively increasing the volume of the battery. Also, the step (2) includes mounting the battery top cover 20 on the top of the case 10, and the specific operation is the same as the step (2) in the above method.

One skilled in the art will appreciate that the number of cells can be any number. Therefore, the present application also provides a method of manufacturing a bipolar battery for manufacturing a battery including four or more battery cells. The method comprises the following steps:

(1) Providing a shell 10 and N battery units which are fixed as a whole and electrically connected in sequence, wherein N is greater than 4, and the shell 10 is provided with a through groove 10' for accommodating the N battery units;

(2) Installing the N battery cells in the through groove 10' of the housing 10, and sealing the housing 10; and

(3) Electrolyte is injected into the through groove 10'.

Wherein the N battery cells include the positive monopolar plate 7, the negative monopolar plate 9, and the first bipolar plate 11, the second bipolar plate 12, and the third bipolar plate 13 manufactured according to the above-described method of the present application. The first bipolar plate 11 includes a positive plate 111 and a negative plate 112, the second bipolar plate 12 includes a positive plate 121 and a negative plate 122, and the third bipolar plate 13 includes a positive plate 131 and a negative plate 132.

When the bipolar plate and the positive and negative unipolar plates are specifically arranged (stacked), the following are caused: the positive single-electrode plate 7 and the negative electrode plate 122 of the second double-electrode plate 12 are included in the first cell a; the positive electrode plate 121 of the second bipolar plate 12 and the negative electrode plate 132 of the first third bipolar plate 13 are included in the second cell B; the positive plate 131 of the first said third bipolar plate 13 and the negative plate 132 of the second third bipolar plate 13 are contained in a third cell C, arranged in this way \8230; the (N-2) th positive electrode plate 131 of the third bipolar plate 13 and the negative electrode plate 112 of the first bipolar plate 11 are included in the (N-1) th cell; the positive electrode plate 111 and the negative electrode plate 9 of the first bipolar plate 11 are included in the nth battery cell. Also, a separator is disposed between the monomers. Also, in a practical battery product, a plurality of the above-described electrode plates may be included in each battery cell. Namely:

in the first monomer A, a plurality of positive single-pole plates 7 and a plurality of negative plates 122 of the second double-pole plate 12 are arranged, and the upper, lower, positive and negative poles are overlapped in a staggered way and are separated by a diaphragm 15;

in the second cell B, a positive plate 121 provided with a plurality of second bipolar plates 12 and a negative plate 132 provided with a first plurality of third bipolar plates 13 are alternately stacked with upper and lower positive and negative electrodes being separated by a separator 15 (one set of third bipolar plates 13 in each cell is composed of a plurality of third bipolar plates 13);

in the third cell C, a first group of positive plates 131 of a plurality of third bipolar plates 13 and a second group of negative plates 132 of the third bipolar plates 13 are arranged, and the upper positive electrode, the lower positive electrode and the negative electrode are alternately superposed and separated by a diaphragm 15;

……；

in the (N-1) th single body, an (N-2) th group of positive plates 131 of a plurality of third bipolar plates 13 and a plurality of negative plates 112 of a first bipolar plate 11 are arranged, and the upper positive electrode and the lower positive electrode are overlapped in a staggered mode, and the positive electrode and the negative electrode are separated by a diaphragm 15;

in the nth cell, a positive electrode plate 111 having a plurality of first bipolar plates 11 and a plurality of negative monopolar plates 9 are alternately stacked one on another in a vertical direction and in a vertical direction, and the positive and negative electrodes are separated from each other by a separator 15.

In other words, for a battery including four or more battery cells, the structure is similar to that of four cells. For example, the battery comprises five single bodies, a first single body, a second single body, a fourth single body and a fifth single body, the used polar plates are completely the same as the polar plates of the four single bodies, and only the bipolar plates used by the third single body are the third bipolar plates 3; similarly, for six single cells, the first and second single cells, and the fifth and sixth single cells, the used polar plates are identical to the four single cells, except that the bipolar plates used by the third and fourth single cells are the third bipolar plate 13. That is, for a battery including more than four battery cells, the plate types of the first and second cells in the order are identical to the plate types of the first and second cells of the four battery cells, the plate types of the first and second cells in the order are also identical to the plate types of the first and second cells in the order, and the plate types of the first and second cells between the first and second cells in the order and the second cell in the order are all the third bipolar plates 13.

For how to mount and fix the bipolar plate, the positive and negative single plates and the diaphragm to constitute the battery cells (and make the electrical connection between the battery cells (realized by the wires inside the bipolar plate, as described above)), see the related contents described in the patent application CN 202011043045.9. The skilled person can also carry out this according to his knowledge.

From the foregoing description, one skilled in the art can produce cells comprising any number of cells using the positive and negative unipolar plates and bipolar plates provided herein.

The materials and acronyms used herein are described as follows:

the material for injection molding comprises engineering plastics ABS (terpolymer of acrylonitrile (A), butadiene (B) and styrene (S)), PP (also called polypropylene, belonging to one of plastics), PVC (namely polyvinyl chloride), PE (namely polyethylene, a thermoplastic resin), PS (also called polystyrene, being a thermoplastic plastic), PBT (namely a kind of plastic with polybutylene terephthalate as a main body), PTFE (polytetrafluoroethylene in Chinese, called plastic king), PET (polyethylene terephthalate, called polyester resin) and RPET (commonly-used recycled polyethylene terephthalate).

The rubber for injection molding comprises: silicone rubber, ethylene propylene diene monomer, butadiene rubber, styrene butadiene rubber, isoprene rubber, fluororubber, or the like. The injection molding foaming material comprises: EPE (Expanded polyethylene, which is commonly called pearl cotton), EPP (also called polypropylene Expanded resin), EPVC (E-PVC Expanded cotton), EVA (ethylene-vinyl acetate copolymer and rubber plastic Expanded material made therefrom), EPS (Polystyrene foam Expanded Polystyrene, which is a light polymer), EPU (sponge), EPER (plastic), EUF (plastic), EPF (plastic), and Expanded epdm, expanded styrene butadiene rubber, expanded chloroprene rubber, expanded silicone rubber, etc.

Features of several embodiments and detailed aspects of the present application are summarized above. Numerous and varied changes, substitutions and alterations can be made by those skilled in the art without departing from the spirit and scope of this application, and all such equivalent constructions are intended to be within the scope of this application.

Claims

1. A method of manufacturing a bipolar plate for a bipolar battery, comprising the steps of:

(a) Prefabricating a plurality of metal wires (1);

(b) -arranging the plurality of metal wires (1) substantially parallel, spaced apart from each other and having a portion thereof located in an injection mould as an injection insert, the plurality of metal wires (1) extending in a first direction (X), the injection mould having therein a plastic cavity extending in a second direction (Y) different from the first direction (X) and a plastic cavity located at the periphery;

(c) Performing injection molding in an injection mold to form a current collector (3), wherein the formed current collector (3) comprises a part of the plurality of metal wires (1) located in the injection mold, a plurality of cross rods (2) formed in the plastic mold cavity and a frame (4), and the plurality of cross rods (2) extend along the second direction (Y) so as to intersect with the plurality of metal wires (1) and be fixed together; and wherein, along said first direction (X), said current collector (3) comprises a first section (31) and a second section (32) separated by a separation seal (5);

(d) After the injection molding is finished, jacking up the current collector (3) and moving the current collector by a fixed step length so as to draw the next part of the plurality of metal wires (1) into the injection mold;

(e) Repeating steps (c) and (d) to produce a plurality of said current collectors (3) connected together;

(f) -phase separating a plurality of said current collectors (3) connected together; and

(g) Wrapping or coating a negative electrode active material (8) and a positive electrode active material (6) on the first segment (31) and the second segment (32) of each current collector (3) respectively, thereby forming a negative electrode plate and a positive electrode plate respectively.

2. A method of manufacturing a bipolar plate for a bipolar battery, comprising the steps of:

A. prefabricating a plurality of metal wires (1);

B. -arranging the plurality of metal wires (1) substantially parallel, spaced apart from each other, in an injection mould as an injection insert, the plurality of metal wires (1) extending in a first direction (X), the injection mould having therein a plastic cavity extending in a second direction (Y) different from the first direction (X), and a plastic cavity at the periphery;

C. performing injection molding in an injection mold to form a current collector (3), wherein the formed current collector (3) comprises the plurality of metal wires (1), a plurality of cross bars (2) formed in the plastic cavity and a frame (4), and the plurality of cross bars (2) extend along a second direction (Y) so as to intersect with the plurality of metal wires (1) and be fixed together; and wherein, along said first direction (X), said current collector (3) comprises a first section (31) and a second section (32) separated by a separation seal (5);

D. after the injection molding is finished, jacking up the current collector (3) and enabling the current collector to leave the injection mold; and

E. and respectively wrapping or coating the first section (31) and the second section (32) of the current collector (3) with a negative electrode active substance (8) and a positive electrode active substance (6) so as to respectively form a negative electrode plate and a positive electrode plate.

3. A method according to claim 1 or 2, wherein the separation seal (5) comprises two sealing stations (51, 52) spaced apart from each other.

4. The method according to claim 1 or 2, wherein both ends of the plurality of wires (1) of the current collector (3) exceed the rim (4) to form a first excess portion (101) adjacent to the first section (31) and a second excess portion (102) adjacent to the second section (32), the first excess portion (101) being provided with a first end seal (5') and the second excess portion (102) being provided with a second end seal (5 ").

5. The method according to claim 4, wherein the bipolar plate produced is a first bipolar plate (11), in which first bipolar plate (11) the first end seal (5 ') comprises only one sealing land (51'), the second end seal (5 ") comprising two sealing lands (51", 52 ") spaced apart from each other.

6. The method according to claim 4, wherein the bipolar plate produced is a second bipolar plate (12), in which second bipolar plate (12) the first end seal (5 ') comprises two sealing lands (51 ', 52 ') spaced apart from each other, the second end seal (5 ") comprising only one sealing land (51").

7. The method according to claim 4, wherein the bipolar plate produced is a third bipolar plate (13), in which third bipolar plate (13) the first end seal (5 ') comprises only one seal land (51'), the second end seal (5 ") also comprising only one seal land (51").

8. The method according to claim 4, wherein the bipolar plate produced is a fourth bipolar plate (14), in which fourth bipolar plate (14) the first end seal (5 ') comprises two sealing lands (51 ', 52 ') spaced apart from each other, the second end seal (5 ") also comprising two sealing lands (51", 52 ") spaced apart from each other.

9. The method of claim 3, wherein: each of the two spaced-apart sealing stages has a width in the first direction (X) of 2-20mm and a gap therebetween of 0.5-5 mm; wherein the gap is used for filling resin glue.

10. The method of claim 3, wherein: each of the sealing stages extends in a second direction (Y) and is formed with elastic through-holes (53) near both ends thereof.

11. The method of claim 3, wherein: in a third direction (Z) perpendicular to the first direction (X) and the second direction (Y), the sealing table has a top portion and a bottom portion, the top portion exceeds the top portion of the frame (4) by 0.2-3 mm, and the bottom portion is lower than the bottom portion of the frame (4) by 0.05-1 mm.

12. The method of claim 1 or 2, wherein: the distance (d 1) between the metal wires (1) is 2-20mm, and the distance (d 2) between the cross rods (2) is 2-30mm; the first direction (X) and the second direction (Y) are substantially perpendicular to each other.

13. A method of manufacturing a unipolar plate of a bipolar battery, comprising the steps of:

(a) Prefabricating a plurality of metal wires (1);

(b) The plurality of metal wires (1) are arranged substantially parallel and spaced apart from each other and a part of them is located in an injection mould as an injection insert, the plurality of metal wires (1) extending in a first direction (X), the injection mould having therein a plastic cavity extending in a second direction (Y) different from the first direction (X),

And a plastic cavity located at the periphery;

(c) Performing injection molding in an injection mold to form a current collector (3), wherein the formed current collector (3) comprises a part of the plurality of metal wires (1) located in the injection mold, a plurality of cross bars (2) formed in the plastic cavity and a frame (4), and the plurality of cross bars (2) extend along the second direction (Y) so as to intersect with the plurality of metal wires (1) and be fixed together;

(d) After the injection molding is finished, jacking the current collector (3) and moving the current collector by a fixed step length so as to draw the next part of the plurality of metal wires (1) into the injection mold;

(e) Repeating steps (c) and (d) so as to make a plurality of said current collectors (3) connected together;

(g) Coating or coating a negative electrode active substance (8) or a positive electrode active substance (6) on each current collector (3) so as to form a negative unipolar plate (9) or a positive unipolar plate (7);

wherein, on each formed current collector (3), two ends of the plurality of metal wires (1) exceed the frame (4) to form a first exceeding part and a second exceeding part, the first exceeding part is provided with a first end sealing part (5 '), and the second exceeding part is provided with a second end sealing part (5'); and is provided with

Wherein one of the first end seal (5') and the second end seal (5 ") comprises one sealing land and the other two spaced sealing lands; the plurality of wires (1) extend from the first end seal (5 ') or the second end seal (5') comprising two sealing stations for conducting electrical current.

14. A method of manufacturing a unipolar plate of a bipolar battery, comprising the steps of:

A. prefabricating a plurality of metal wires (1);

C. performing injection molding in an injection mold to form a current collector (3), wherein the formed current collector (3) comprises the plurality of metal wires (1), a plurality of cross bars (2) formed in the plastic cavity and a frame (4), and the plurality of cross bars (2) extend along a second direction (Y) so as to intersect with the plurality of metal wires (1) and be fixed together;

D. after the injection molding is finished, jacking the current collector (3) and enabling the current collector to leave the injection mold; and

E. the current collector (3) is respectively wrapped or coated with a negative electrode active substance (8) or a positive electrode active substance (6) to form a negative unipolar plate (9) or a positive unipolar plate (7),

wherein two ends of the plurality of metal wires (1) exceed the frame (4) to form a first exceeding part and a second exceeding part, a first end sealing part (5 ') is formed on the first exceeding part, and a second end sealing part (5') is formed on the second exceeding part; and is

Wherein one of the first end seal (5') and the second end seal (5 ") comprises one sealing land and the other comprises two spaced sealing lands; the plurality of wires (1) extend from the first end seal (5 ') or the second end seal (5') comprising two sealing stations for conducting electrical current.

15. The method of claim 13 or 14, wherein: each of the two spaced-apart sealing stages has a width in the first direction (X) of 2-20mm and a gap therebetween of 0.5-5 mm; wherein the gap is used for filling resin glue.

16. The method of claim 13 or 14, wherein: each of the sealing stages extends in a second direction (Y) and is formed with elastic through holes (53) near both ends thereof.

17. The method of claim 13 or 14, wherein: in a third direction (Z) perpendicular to the first direction (X) and the second direction (Y), the sealing table has a top portion and a bottom portion, the top portion exceeds the top portion of the frame (4) by 0.2-3 mm, and the bottom portion is lower than the bottom portion of the frame (4) by 0.05-1 mm.

18. The method of claim 13 or 14, wherein: the distance (d 1) between the metal wires (1) is 2-20mm, and the distance (d 2) between the cross rods (2) is 2-30mm; the first direction (X) and the second direction (Y) are substantially perpendicular to each other.

19. A bipolar plate for a bipolar battery manufactured by the method of any one of claims 1 to 12.

20. A unipolar plate of a bipolar battery manufactured by the method of any one of claims 13-18.

21. A method of manufacturing a bipolar battery, comprising:

(1) Providing a shell (10) and a first battery unit (A) and a second battery unit (B), wherein the shell (10) is provided with a through groove (10') for accommodating the first battery unit (A) and the second battery unit (B), and the first battery unit (A) and the second battery unit (B) are fixed into a whole and are electrically connected with each other;

(2) Mounting the first and second battery cells (A, B) in the through groove (10') of the housing (10), and sealing the housing (10); and

(3) Injecting electrolyte into the through groove (10'),

wherein the first and second battery cells (a, B) comprise a positive unipolar plate (7) produced according to the method of any one of claims 13 to 18, a negative unipolar plate (9), and a fourth bipolar plate (14) produced according to the method of claim 8;

wherein the fourth bipolar plate (14) comprises a positive plate (141) and a negative plate (142); and is provided with

Wherein the negative plate (142) and the positive monopolar plate (7) of the fourth bipolar plate (14) are comprised in a first cell (A), and the positive plate (141) and the negative monopolar plate (9) of the fourth bipolar plate (14) are comprised in a second cell (B).

22. A method of manufacturing a bipolar battery, comprising:

(1) Providing a shell (10) and first, second and third battery monomers (A, B and C), wherein the shell (10) is provided with a through groove (10') for accommodating the first, second and third battery monomers (A, B and C), and the first, second and third battery monomers (A, B and C) are fixed into a whole and are electrically connected in sequence;

(2) Mounting the first, second and third battery cells (A, B, C) in the through groove (10') of the housing (10) and sealing the housing (10); and

(3) Injecting electrolyte into the through groove (10'),

wherein the first, second and third battery cells (a, B, C) comprise a positive unipolar plate, a negative unipolar plate manufactured according to the method of any one of claims 13 to 18, a first bipolar plate (11) manufactured according to the method of claim 5, and a second bipolar plate (12) manufactured according to the method of claim 6;

wherein the first bipolar plate (11) comprises a positive plate (111) and a negative plate (112), and the second bipolar plate (12) comprises a positive plate (121) and a negative plate (122); and is

Wherein the positive single-electrode plate (7) and the negative plate (122) of the second double-electrode plate (12) are contained in a first battery cell (A); a positive electrode plate (121) of the second bipolar plate (12) and a negative electrode plate (112) of the first bipolar plate (11) are contained in a second battery cell (B); the positive electrode plate (111) and the negative monopolar plate (9) of the first bipolar plate (11) are contained in a third battery cell (C).

23. A method of manufacturing a bipolar battery, comprising:

(1) Providing a shell (10) and first, second, third and fourth battery monomers (A, B, C and D), wherein the shell (10) is provided with a through groove (10') for accommodating the first, second, third and fourth battery monomers (A, B, C and D), and the first, second, third and fourth battery monomers (A, B, C and D) are fixed into a whole and are electrically connected in sequence;

(2) Mounting the first, second, third and fourth battery cells (A, B, C, D) in the through groove (10') of the housing (10) and sealing the housing (10); and

(3) Injecting electrolyte into the through groove (10'),

wherein the first, second, third and fourth battery cells (a, B, C, D) comprise a positive unipolar plate (7) produced according to the method of any one of claims 13 to 18, a negative unipolar plate (9), and a first bipolar plate (11) produced according to the method of claim 5, a second bipolar plate (12) produced according to the method of claim 6, a third bipolar plate (13) produced according to the method of claim 7;

wherein the first bipolar plate (11) comprises a positive plate (111) and a negative plate (112), the second bipolar plate (12) comprises a positive plate (121) and a negative plate (122), and the third bipolar plate (13) comprises a positive plate (131) and a negative plate (132); and is

Wherein the positive single-electrode plate (7) and the negative plate (122) of the second double-electrode plate (12) are contained in a first battery cell (A); the positive plate (121) of the second bipolar plate (12) and the negative plate (132) of the third bipolar plate (13) are contained in a second cell (B); the positive plate (131) of the third bipolar plate (13) and the negative plate (112) of the first bipolar plate (11) are contained in a third cell (C); the positive electrode plate (111) and the negative monopolar plate (9) of the first bipolar plate (11) are contained in a third battery cell (D).

24. A method of manufacturing a bipolar battery, comprising:

(1) Providing a shell (10) and N battery units which are fixed integrally and electrically connected in sequence, wherein N is greater than 4, and a through groove (10') for accommodating the N battery units is formed in the shell (10);

(2) Mounting the N battery cells in the through groove (10') of the shell (10) and sealing the shell (10); and

(3) Injecting electrolyte into the through groove (10'),

wherein the N battery cells comprise a positive monopolar plate (7), a negative monopolar plate (9) produced according to the method of any one of claims 13 to 18, and a first bipolar plate (11) produced according to the method of claim 5, a second bipolar plate (12) produced according to the method of claim 6, a third bipolar plate (13) produced according to the method of claim 7;

Wherein the positive single-electrode plate (7) and the negative plate (122) of the second double-electrode plate (12) are contained in a first battery cell (A); the positive plate (121) of the second bipolar plate (12) and the negative plate (132) of the first of the third bipolar plates (13) are contained in a second cell (B); the positive plate (131) of the first of said third bipolar plates (13) and the negative plate (132) of the second third bipolar plate (13) are contained in a third cell (C), arranged in such a way; by analogy, the positive plate (131) of the (N-2) th third bipolar plate (13) and the negative plate (112) of the first bipolar plate (11) are contained in the (N-1) th cell; the positive plate (111) and the negative unipolar plate (9) of the first bipolar plate (11) are included in the nth battery cell.

25. The method of any one of claims 21-24, wherein: the step (2) comprises installing a battery top cover (20) on the top of the shell (10) and sealing the battery top cover (20) and the shell (10).

26. The method of claim 25, wherein: the housing (10) is substantially U-shaped in cross section and comprises two opposite parallel side walls (103, 104) and a bottom wall (105) connecting the two side walls (103, 104) and the bottom wall (105) defining the through slot (10') and forming an opening at the top.

27. The method of claim 26, wherein: in the step (2), the battery top cover (20) is fixed in the opening of the shell (10) in an elastic clamping mode.

28. The method of claim 27, wherein: the two parallel grooves (1031, 1041) are arranged on the two side walls (103, 104) of the shell (10) near the top, the battery further comprises two wedge-shaped strips (26) which can be inserted into the grooves (1031, 1041), and the two sides of the battery top cover (20) are provided with inversions (27) matched with the two wedge-shaped strips (26), so that the battery top cover (20) is fixed in the opening by means of the matching of the wedge-shaped strips (26) and the inversions (27) and self-locking is realized.

29. The method of any one of claims 21-24, wherein: each sealing platform is elastically deformed under the pressure action of the battery top cover (20), so that sealing walls of each battery monomer are formed, and a glue injection groove (25) is formed between every two adjacent sealing walls.