CN114361681A

CN114361681A - Method for manufacturing bipolar horizontal battery and bipolar horizontal battery

Info

Publication number: CN114361681A
Application number: CN202011043045.9A
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: 2020-09-28
Filing date: 2020-09-28
Publication date: 2022-04-15

Abstract

The present application relates to a method of manufacturing a bipolar horizontal battery and a bipolar horizontal battery. The method comprises the following steps: providing a battery cell of a horizontal battery; placing the battery core as an embedded part into an injection mold; forming a battery shell in an injection mold in an injection molding manner, so that the battery shell surrounds the battery core and is combined into a whole, wherein a circulating channel is formed between the battery core and the battery shell for electrolyte to flow through; respectively installing a top cover and a bottom cover on the top surface and the bottom surface of the battery shell and sealing the top cover and the bottom cover, so that a sealed space is formed inside the battery shell for storing electrolyte; and injecting an electrolyte into the battery case. The horizontal battery manufactured according to the method not only can directly, conveniently and stably fix the battery core and the battery shell together, but also is beneficial to conveniently and effectively realizing the sealing between the battery cells of the battery core.

Description

Method for manufacturing bipolar horizontal battery and bipolar horizontal battery

Technical Field

The present disclosure relates to the field of batteries, and more particularly, to a method for manufacturing a horizontal battery and a horizontal battery manufactured by the same.

Background

In the modern society, batteries have been widely used in various fields. The types of batteries are also varied depending on the application. Among them, a horizontal battery, which is one of the stack type batteries, is generally used as a large-capacity battery because it can include a plurality of cells, and is applicable to starting of automobiles, ships, construction machines, airplanes, locomotives, and the like, and also to various fields such as energy storage, backup power, forklifts, and the like.

The existing horizontal battery manufacturing process is as follows: the method comprises the steps of respectively manufacturing a battery core (a plurality of single battery clusters formed by stacking and fixing a bipolar plate, a positive single plate, a negative electrode plate, a diaphragm and the like) and a battery shell (also called a battery jar) of the horizontal battery, then assembling and fixing the battery core in the battery shell, then installing a top cover on the top of the battery shell, sealing the joint of the top cover and the battery shell, and finally injecting electrolyte into the battery shell, thereby forming the complete battery.

However, this process of manufacturing a horizontal battery has at least the following disadvantages:

first, sealing between the individual cells of the battery cell is not easily accomplished. Since the individual cells of the battery are connected in series, they must be connected by means of conductors (e.g. wires) or by welding, but at the same time do not allow the electrolyte to flow between the individual cells. Therefore, it is generally necessary to design a special structure to seal the battery cells and prevent the occurrence of liquid leakage or gas leakage between the battery cells.

Secondly, the mounting and fixing structure between the battery cell and the battery case is complicated, and a special structure for fitting each other needs to be designed between the battery cell and the battery case to ensure that the battery cell and the battery case are firmly fitted and fixed together, and positive and negative terminals can be led out from the battery cell to the outside of the battery case. The design of the matching structure increases the manufacturing cost of the whole battery; also, since an additional step is required to combine the battery cell and the battery case, the complexity of processes and processes is increased.

Disclosure of Invention

One technical problem to be solved by the present application is to overcome at least one of the above-mentioned deficiencies in the prior art, and to provide a method for manufacturing a bipolar horizontal battery, according to which the horizontal battery can be manufactured such that a battery cell and a battery case are directly, conveniently and stably fixed together, and also facilitate the convenient and effective sealing between the battery cells of the battery cell.

Another technical problem that this application will solve is to provide a horizontal battery, its simple, the lower, the suitable mass production of manufacturing process of not only manufacturing process, manufacturing cost, the leakproofness between each battery monomer of this battery is good moreover, can prevent effectively that the liquid or gas channeling phenomenon from taking place between each battery monomer to the fixed mode of battery core and battery case is simple, convenient the realization.

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

in brief, the method of manufacturing a bipolar horizontal battery provided by the present application is based on the idea that: the manufacturing method comprises the steps of firstly completing the manufacturing of the battery core, after the battery core is completed, placing the battery core as an embedded part into an injection mold for forming a battery shell, and then performing injection molding in the mold to form the battery shell, so that the battery shell is directly combined with the battery core into a whole after being formed. More specifically, the battery case is integrated with the battery cell at both ends (i.e., portions of the battery cell where the bus bars are formed) so that the positive and negative terminals of the battery can be drawn out from the bus bars, while both sides of the battery cell and the battery case are spaced apart from each other so that a circulation passage through which the electrolyte flows is formed. Then, a top cover and a bottom cover are respectively arranged at the top end and the bottom end of the combination body of the battery shell and the battery core (namely, the top cover and the bottom cover are respectively arranged at the upper edge and the lower edge of the battery shell) and are sealed, and then electrolyte is injected to form the complete battery.

A first aspect of the present application is to provide a method of manufacturing a bipolar horizontal battery according to the above inventive concept, including the steps of:

(a) providing a battery cell of a horizontal battery;

(b) placing the battery core as an embedded part into an injection mold;

(c) forming a battery shell in the injection mold in an injection manner, enabling the battery shell to surround the battery core and be combined into a whole, wherein a circulating channel is formed between the battery core and the battery shell for electrolyte to flow through;

(d) respectively installing a top cover and a bottom cover on the top surface and the bottom surface of the battery shell and sealing the top cover and the bottom cover, so that a sealed space is formed inside the battery shell for storing electrolyte; and

(e) injecting an electrolyte into the battery case.

In embodiments provided herein, the step (a) comprises:

(a1) providing a frame, a plurality of bipolar plates, a plurality of positive unipolar plates, and a plurality of negative unipolar plates;

(a2) stacking the bipolar plates, the positive single-pole plates and the negative single-pole plates in the frame to form a plurality of single batteries, wherein the metal leading-out ends of the positive single-pole plates and the metal leading-out ends of the negative single-pole plates face the outside;

(a3) installing a pressure cover plate on the top of the frame to fix the bipolar plates, the positive monopolar plates and the negative monopolar plates in the frame; and

(a4) and welding the metal leading-out ends of the positive single-pole plates and the metal leading-out ends of the negative single-pole plates respectively to form a bus bar, and leading out positive and negative terminals from the bus bar.

Preferably, the frame is foldable and comprises a bottom support panel and foldable wings on either side of the bottom support panel, the foldable wings being foldable to be generally perpendicular to the bottom support panel.

In the step (a2), the bipolar plates, the positive unipolar plates, and the negative unipolar plates are placed on the bottom support plate, and the foldable wing plate is folded to a position substantially perpendicular to the bottom support plate, or the foldable wing plate is first folded to a position substantially perpendicular to the bottom support plate, and then the bipolar plates, the positive unipolar plates, and the negative unipolar plates are placed on the bottom support plate, so that the bipolar plates, the positive unipolar plates, and the negative unipolar plates are positioned on the bottom support plate and between the foldable wing plates.

The specific structure and stacking manner of the bipolar plates, the positive monopolar plates and the negative monopolar plates are not the focus of the present application, and those skilled in the art can use bipolar plates, positive monopolar plates and negative monopolar plates with suitable structures and stack them in a suitable manner to form a plurality of battery cells, for example, the structure and stacking manner of the bipolar plates, positive monopolar plates and negative monopolar plates disclosed in chinese patent application CN202010353387.4 can be used.

Preferably, a plurality of through holes through which an electrolyte flows are formed in the bottom support plate of the frame and/or the foldable wing plate, and in the step (e), the electrolyte is introduced into the respective battery cells through the plurality of through holes.

Preferably, the foldable wing plate and the pressure cover plate can be provided with clamping structures; in step (a3), the pressure cover plate is placed on top of the frame and the clamping structure is clamped, so that the bipolar plates and the positive and negative unipolar plates are fixed in the frame in a self-locking manner. The clamping structure comprises a hook arranged on the pressure cover plate and a cover closing window which is arranged on the foldable wing plate and can be matched with the hook; in step (a3), the plurality of bipolar plates and the plurality of positive and negative unipolar plates are elastically deformed by applying pressure to the pressure cover plate so that the hooks enter the capping windows of the foldable wing plates, and then the application of pressure is stopped, at which time the plurality of bipolar plates and the plurality of positive and negative unipolar plates are restored by elastic deformation so that the hooks are firmly snapped into the capping windows. The fixing mode is simple and convenient to operate, and the fixing mode is very stable and not easy to loosen after being fixed.

Preferably, the bipolar plate includes a negative electrode plate, a positive electrode plate, and a separation seal therebetween, which are integrally formed. Since the negative and positive plates of each bipolar plate will be located in different cells, respectively, the separation seal between the two plates helps to achieve isolation between the different cells (see CN202010353387.4 for details).

Preferably, the frame comprises a plurality of sections with gaps between the sections; in the step (a2), the negative electrode plate and the positive electrode plate of each bipolar plate are respectively located at two different but adjacent sections of the frame, and the positive monopolar plate and the negative monopolar plate are respectively located at two outermost sections of the frame, so that in each section of the frame, the negative electrode plate of one bipolar plate and the positive electrode plate or the positive monopolar plate of the other bipolar plate form a single cell, or the positive electrode plate of one bipolar plate and the negative electrode plate or the negative monopolar plate of the other bipolar plate form a single cell, and a gap is formed between the single cells.

For example, for a battery having only two cells, the frame includes two sections. In one section, the negative plate of a bipolar plate and the positive plate form a single battery (separated by a diaphragm); in another section, the positive and negative unipolar plates of the bipolar plate form a single cell (separated by a separator in the middle). Similarly, if the battery has three cells, the frame includes three sections. In one section, the negative plate of a bipolar plate and the positive plate form a single battery (separated by a diaphragm); in the second section, the positive plate of the bipolar plate forms a cell (separated by a separator) with the negative plate of the other bipolar plate; in a third section, the positive plate of the further bipolar plate and the negative unipolar plate form one cell (separated in the middle by a separator). If the battery has more than three battery cells, the bipolar plate, the positive monopolar plate and the negative monopolar plate are also stacked in a similar manner. See in particular the disclosure of chinese patent application CN 202010353387.4.

It should be noted that only the plate configuration of one cell (including the positive electrode, the negative electrode and the separator therebetween) in each battery cell is described herein. In an actual battery product, there are many such battery cells within each battery cell.

Preferably, in the step (c), the gaps between the battery cells are filled with the molten plastic so that partition walls are formed between the adjacent battery cells after cooling to separate the adjacent battery cells. Because the molten plastic has better fluidity, the gaps among the battery monomers can be fully filled, and the formed partition wall can effectively realize the isolation among the battery monomers and prevent the liquid leakage or the gas leakage among the battery monomers.

Preferably, in the step (c), the battery case is combined with the bus bars of the battery cell at both ends thereof, and the circulation passage is formed between both sides of the battery cell and the respective inner walls of the battery case for circulation of the electrolyte. Wherein the width of the circulating channel is 0.5-20 mm. The circulating channel with the width can ensure that the electrolyte can smoothly circulate in the circulating channel, does not cause overlarge integral space of the battery, and is favorable for ensuring the compactness of the structure of the battery. Those skilled in the art can design the width of the circulation channel within the above range according to the overall size of the battery and the flow rate of the electrolyte to be circulated when designing the battery. Preferably, the width of the circulation channel is 2-10 mm. For example, the width of the circulation channel may be 4mm, 6mm or 8 mm. The circulation channel within the above size range can effectively achieve the smooth circulation of the electrolyte therein and the minimization of the overall size of the battery.

In the embodiment of the present application, a plurality of relief valve mounting seats are disposed on the outer side of the top cover, and in the step (d), a relief valve is mounted on each relief valve mounting seat; and (d) forming a groove matched with the side wall of the battery shell on the inner side of the top cover, and matching the groove with the side wall of the battery shell and sealing the groove and the side wall of the battery shell in step (d).

Preferably, the upper end of the sidewall of the battery case has a thickness smaller than that of the sidewall main body, the upper end is inserted into the groove of the top cap to form a seal, and the outer surface of the sidewall main body is flush with the outer surface of the top cap. This kind of structure not only helps realizing forming effectual, firm sealed between the lateral wall of battery case and the top cap to prevent that electrolyte from revealing, make the whole surperficial level of battery moreover.

In an embodiment of the present application, the bottom cover has a plurality of apertures thereon, and in the step (e), the electrolyte is injected into the battery case through the plurality of apertures; a groove fitted with the side wall of the battery case is formed at the inner side of the bottom cover, and in the step (d), the groove is fitted with the side wall of the battery case and sealed.

Preferably, the lower ends of the side walls of the battery case have a thickness smaller than that of the side wall main body, the lower ends are inserted into the grooves of the bottom cover to form a seal, and the outer surfaces of the side wall main bodies are flush with the outer surface of the bottom cover. This structure not only helps realizing forming effective, firm sealed between the lateral wall of battery shell and the bottom to prevent the electrolyte to reveal, make the whole surperficial level of battery moreover.

A second aspect of the present application is also to provide a method of manufacturing a bipolar horizontal battery according to the above inventive concept, including:

(i) providing a battery core; and

(ii) and placing the battery core as an embedded part into an injection mold, and performing injection molding in the injection mold to form a battery shell, so that the battery shell and the battery core are combined into a whole, and a circulating channel is formed between the battery shell and the battery core to allow electrolyte to flow through.

In an embodiment of the present application, the method further includes:

(iii) respectively installing a top cover and a bottom cover on the top surface and the bottom surface of the battery shell and sealing the top cover and the bottom cover, so that a sealed space is formed inside the battery shell for storing electrolyte; and

(iv) and injecting electrolyte into the battery shell, and forming a battery finished product.

In an embodiment of the present application, the battery core includes a plurality of battery cells, each of the battery cells having a gap therebetween; in the step (ii), the gaps between the battery cells are filled with the molten plastic, so that partition walls are formed between the adjacent battery cells after cooling to separate the adjacent battery cells. Due to the flowable nature of the molten plastic, it is able to adequately fill the gaps between the cells. Therefore, the partition wall can form good sealing among the battery cells, so that electrolyte is effectively prevented from flowing between different battery cells, leaking and the like.

A third aspect of the present application is to provide a bipolar horizontal battery manufactured according to the above-described method.

A fourth aspect of the present application is to provide a bipolar horizontal battery, including: the battery core comprises a plurality of battery single cells, and a gap is formed between the battery single cells; and the battery shell is integrated with the battery core in an injection molding mode, and a circulation channel is formed between the battery shell and the battery core for electrolyte to flow through.

In the embodiments of the present application, the width of the circulation channel is 0.5 to 20 mm. The circulating channel with the width can ensure that the electrolyte can smoothly circulate in the circulating channel, does not cause overlarge integral space of the battery, and is favorable for ensuring the compactness of the structure of the battery. Those skilled in the art can design the width of the circulation channel within the above range according to the overall size of the battery and the flow rate of the electrolyte to be circulated when designing the battery. Preferably, the width of the circulation channel is 2-10 mm. For example, the width of the circulation channel may be 4mm, 6mm or 8 mm. The circulation channel within the above size range can effectively achieve the smooth circulation of the electrolyte therein and the minimization of the overall size of the battery.

The bipolar horizontal battery also comprises partition walls which are integrally formed with the battery shell in the injection molding process and are positioned in gaps among the battery single cells, so that the adjacent battery single cells are isolated. The partition wall can form good sealing among the battery monomers, so that electrolyte is effectively prevented from channeling, leaking and the like among different battery monomers.

In the examples provided in this application: the battery cell includes a frame, a plurality of bipolar plates, a plurality of positive unipolar plates, a plurality of negative unipolar plates, and a pressure cover plate. And a plurality of through holes for electrolyte to flow are formed on the bottom surface and the side surface of the frame, so that the electrolyte can enter each single battery through the through holes.

Preferably, the frame and the pressure cover plate are provided with clamping structures which can be matched with each other, so that the bipolar plates and the positive and negative unipolar plates are fixed in the frame in a self-locking manner by means of the clamping structures. The clamping structure comprises a hook arranged on the pressure cover plate and a cover closing window arranged at the top of the frame and matched with the hook. In the manufacturing process, the plurality of bipolar plates, the plurality of positive single-pole plates and the plurality of negative single-pole plates are elastically deformed by applying pressure to the pressure cover plate, so that the hooks enter the cover closing windows of the foldable wing plates, then the application of pressure is stopped, and the plurality of bipolar plates, the plurality of positive single-pole plates and the plurality of negative single-pole plates are elastically deformed and restored at the moment, so that the hooks are firmly clamped in the cover closing windows. The fixing mode is very stable, the operation is simple and convenient, and the fixing mode is very stable and not easy to loosen.

The bipolar plates, the positive single-pole plates and the negative single-pole plates are stacked in the frame and fixed by the pressure cover plate to form the battery cells, and the metal leading-out ends of the positive single-pole plates and the metal leading-out ends of the negative single-pole plates face to the outside and are respectively welded to form a busbar. The bus bars may be further drawn out from both ends of the battery case to constitute positive and negative terminals of the battery. The specific structure and stacking manner of the bipolar plates, the positive monopolar plates and the negative monopolar plates are not the focus of the present application, and those skilled in the art can use bipolar plates, positive monopolar plates and negative monopolar plates with suitable structures and stack them in a suitable manner to form a plurality of battery cells, for example, the structure and stacking manner of the bipolar plates, positive monopolar plates and negative monopolar plates disclosed in chinese patent application CN202010353387.4 can be used.

Preferably, the bipolar plate comprises a negative plate, a positive plate and a separation sealing part between the negative plate and the positive plate which are formed into a whole; the frame comprises a plurality of sections with gaps between the sections; the negative plate and the positive plate of each bipolar plate are respectively positioned in two different but adjacent sections of the frame, and the positive single-pole plates and the negative single-pole plates are respectively positioned in two outermost sections of the frame, so that in each section of the frame, the negative plate of one bipolar plate and the positive plate or the positive single-pole plate of the other bipolar plate form a single battery cell, or the positive plate of one bipolar plate and the negative plate or the negative single-pole plate of the other bipolar plate form a single battery cell, and gaps are formed among the single battery cells, so that partition walls are formed in the gaps in the process of injection molding of the shell. In principle, the number of sections of the frame is designed according to the number of battery cells. That is, for example, for a battery having three cells, the frame should also have three sections. For the stacking manner of the upper bipolar plate, the positive monopolar plate and the negative monopolar plate in each section, refer to the above-mentioned description, and refer to the contents of chinese patent application CN 202010353387.4. And are not described in detail herein.

In the above embodiment, the bipolar horizontal battery further comprises: a bottom cover disposed on a bottom surface of the battery case, wherein: the bottom cover is provided with a plurality of orifices which respectively correspond to the plurality of battery monomers and are used for injecting electrolyte. I.e., how many cells in total, there are openings in the bottom cover so that electrolyte can be injected into each cell. And, the inner side of the said bottom cap is formed with the recess cooperating with sidewall of the said battery casing; and wherein a junction of the battery case and the bottom cover is hermetically coupled.

According to the method for manufacturing the bipolar horizontal battery provided by the application, compared with the prior art, the following technical effects are achieved:

(1) because the battery shell and the battery core are formed into a whole in an injection molding mode, molten plastic can flow into gaps among the battery monomers of the battery core in the injection molding process, and partition walls are formed among the battery monomers, so that sealing among the battery monomers can be effectively realized, and leakage of electrolyte and liquid channeling among different battery monomers are avoided.

(2) The battery shell and the battery core are formed into a whole in an injection molding mode, so that the battery core and the battery shell can be directly, conveniently and stably fixed together, the step of assembling the battery core and the battery shell in the prior art is omitted, the process is simplified, the product quality is improved, and the battery shell is very suitable for batch production.

According to the bipolar horizontal battery provided by the application, because the battery shell and the battery core are molded into a whole by injection, and the battery monomers form the partition wall, the sealing performance between the battery monomers is good, the liquid leakage or the gas leakage phenomenon between the battery monomers can be effectively prevented, the fixing mode of the battery core and the battery shell is simple and convenient to realize, and the overall strength of the combined battery is greatly improved and very stable compared with the bonding structure in the CN202010353387.4 Chinese patent application.

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. 1 is a perspective view of a bipolar horizontal battery (finished product) made according to the method provided herein;

fig. 2A is a front view of a battery cell of the battery shown in fig. 1, fig. 2B is a sectional view a-a of fig. 2A, and fig. 2A, 2B collectively show a product (battery cell) formed in step (a);

fig. 3A to 3C are schematic views (i.e., products formed through steps (B) and (C)) of the battery case after the battery cell shown in fig. 2A and 2B is injection-molded, wherein fig. 3A is a front view of the battery case (including the battery cell), fig. 3B is a sectional view of B-B of fig. 3A, and fig. 3C is a sectional view of C-C of fig. 3A;

fig. 4A to 4E are schematic views after further mounting a top cap and a bottom cap on the battery cell and the battery case shown in fig. 3A to 3C (i.e., the product formed at step (d)); fig. 4A is a front view of the battery case after the top cap and the bottom cap are assembled, fig. 4B is a sectional view taken along line D-D of fig. 4A, fig. 4C is a sectional view taken along line E-E of fig. 4A, fig. 4D is an enlarged view taken along line D of fig. 4B, and fig. 4E is an enlarged view taken along line E of fig. 4B;

fig. 5A and 5B show the frame of the battery cell (i.e., the frame used in step (a 1)) in the embodiment shown in fig. 1-4E before folding, wherein fig. 5A is a front view of the frame in the state before folding, and fig. 5B is a top view of fig. 5A;

fig. 6A is a front view of the frame shown in fig. 5A and 5B after being folded, and fig. 6B is a left view of fig. 6A, which together show the frame after being folded.

FIGS. 7A-7B illustrate one embodiment of a bipolar plate for the cell in the embodiment of FIGS. 1-4E, where FIG. 7A shows a top view of the bipolar plate and FIG. 7B is a cross-sectional view F-F of FIG. 7A;

fig. 8A-8B illustrate an embodiment of a positive or negative unipolar plate of the battery cell of the embodiment of fig. 1-4E, wherein fig. 8A illustrates a top view of the positive or negative unipolar plate and fig. 8B is a bottom view of fig. 8A;

fig. 9A shows a front view of the bipolar plate (i.e., the bipolar plate of fig. 7A and 7B) and the positive and negative unipolar plates (the positive or negative unipolar plates of fig. 8A and 8B) in the cell core of the embodiment of fig. 1-4E, after stacking, and fig. 9B is an enlarged view at I of fig. 9A;

fig. 10A is a top view of a pressure cap plate (i.e., the pressure cap plate used in step (a 3)) of the battery cell in the embodiment shown in fig. 1-4E, and fig. 10B is a left side view of fig. 10A;

fig. 11A, 11B show a structure (structure formed by step (a 3)) in which a bipolar plate (shown in fig. 7A, 7B) and a positive and negative unipolar plate (shown in fig. 8A, 8B) are stacked and fixed on a folded frame, wherein fig. 11A is a front view of the structure and fig. 11B is a left side view of fig. 11A; unlike fig. 2A, 2B, in fig. 11A, 11B, the metal terminals of the positive and negative unipolar plates have not been welded into a bus bar (i.e., step (a4) is not performed);

fig. 12A, 12B illustrate the structure of a top cap of the battery shown in fig. 1, wherein fig. 12A is a bottom view of the top cap, and fig. 12B is a sectional view H-H of fig. 12A;

fig. 13A and 13B illustrate a structure of a bottom cover of the battery shown in fig. 1, wherein fig. 13A is a top view of the bottom cover, and fig. 13B is a cross-sectional view I-I of fig. 13A;

FIGS. 14A and 14B illustrate another bipolar horizontal battery (finished product) made according to the method provided herein, which includes four battery cells; wherein fig. 14A is a sectional view taken along J-J of fig. 14B, and fig. 14B is a top view of the battery;

fig. 15A and 15B illustrate a structure of a battery cell and a battery case (i.e., not including a top cover and a bottom cover) in the embodiment shown in fig. 14A and 14B, wherein fig. 15A is a cross-sectional view taken along K-K of fig. 15B, and fig. 15B is a top view of the structure;

fig. 16A, 16B show the structure of the battery cell in the embodiment shown in fig. 14A, 14B, in which fig. 16A is a front view of the battery cell, and fig. 16B is a sectional view taken along L-L of fig. 16B;

fig. 17A and 17B illustrate a stacked structure of a bipolar plate, a positive monopolar plate, and a negative monopolar plate in the battery cell in the embodiment shown in fig. 16A and 16B, in which fig. 17A is a front view of the stacked structure, fig. 17B is a left side view of fig. 17, and fig. 17C to 17G are partially enlarged views at I, II, III, IV, and V in fig. 17A, respectively, illustrating a connection structure between the battery cells.

Description of reference numerals:

100-bipolar horizontal battery

10-a battery cell; 1-a frame; 2-a bipolar plate; 3-positive single-pole plate; 4-a negative monopolar plate; 5-a pressure cover plate; 11. 12-bottom support plate, foldable wing plate of frame 1; 111. 112-through holes on the bottom support plate and the foldable wing plate; 13-a section of the frame 1; 14-gaps between segments; 21. 22-negative and positive plates of the bipolar plate 2; 31. 41-metal leading-out ends of the positive and negative

unipolar plates

3, 4; 101-a battery cell; 32. 42-bus bar formed by metal leading-out ends 31, 41 of the positive and negative

unipolar plates

3, 4;

20-a battery case; 201-upper end of the side wall; 202-a sidewall body; 203-lower end of side wall

30-a top cover; 301-air release valve mounting seat; 302-a bleed valve; 303-groove

40-bottom cover; 401-orifice; 402-groove

6-partition walls between the battery cells;

p-circulation channel

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 embodiments, a person skilled in the art may make various modifications and changes, and all technical solutions obtained by equivalent changes are within the scope of protection of the present application.

In general, the invention of the present application includes two aspects: a method of manufacturing a bipolar horizontal battery 100 and a bipolar horizontal battery 100 manufactured according to the method.

Referring to fig. 1, a bipolar horizontal battery 100 according to the present application generally includes four main portions, a battery cell 10, a battery case 20, a top cover 30, and a bottom cover 40. Wherein the battery cell 10 is located inside the battery case 20 (therefore, the portion in fig. 1 is cited as a dotted line); the top cap 30 and the bottom cap 40 are mounted on the top and the bottom of the battery case 20, respectively, and the joints with the battery case 20 are sealed, so that a sealed space is formed inside the battery case 20 for the electrolyte to flow therein. As shown in fig. 1, the top cover 30 has a relief valve 302 thereon for discharging exhaust gas. Positive and

negative terminals

33 and 43 are formed at both ends of the battery case 20 to be externally connected to the battery cell 10.

In the prior art, when manufacturing a horizontal battery, a battery core and a battery case are generally manufactured respectively, the battery core is then assembled into the battery case and fixed, a top cover is then installed on the top of the battery case and sealed, and finally, an electrolyte is injected into the battery case to form a complete battery. This manufacturing method is disadvantageous in that it is disadvantageous to achieve sealing between the respective battery cells of the battery core, which are connected in series by means of a conductor (e.g., a wire), and thus easily causes a leakage phenomenon at the connection, and makes the assembly structure of the battery core and the battery case complicated.

The application adopts a brand new invention concept: the manufacturing method comprises the steps of firstly completing the manufacturing of the battery core, then placing the battery core as an embedded part into an injection mold for forming the battery shell after the battery core is completed, and then forming the battery shell in the mold in an injection molding mode, so that the battery shell is directly combined with the battery core into a whole during injection molding. The structure not only can strengthen the sealing between each battery monomer of the battery core in an injection molding mode, but also reduces the assembling procedures between the battery core and the battery shell and optimizes the production process, thereby reducing the production cost and being beneficial to large-scale production.

Specifically, the method of manufacturing a bipolar horizontal battery 100 as provided herein generally includes the steps of:

(a) a battery cell 10 (shown in fig. 2A, 2B) providing a horizontal battery;

(b) placing the battery core 10 as an embedded part into an injection mold (the injection mold is not shown, and the specific mold structure and size can be designed by those skilled in the art according to the shape and size of the battery core, the number of battery cells, the shape and size of the battery case to be formed, etc.);

(c) forming a battery case 20 by injection molding (e.g., injecting molten plastic) in the injection mold such that the battery case 20 surrounds the battery cell 10 and is integrated with the battery cell 10 (as shown in fig. 3A-3C), wherein a circulation channel P is formed between the battery cell 10 and the battery case 20 for electrolyte to flow therethrough;

(d) a top cover 30 and a bottom cover 40 (shown in fig. 4A-4E) are respectively mounted on the top surface and the bottom surface of the battery case 20 and sealed (a specific sealing manner can be a conventional heat sealing or glue sealing manner), so that a sealed space is formed inside the battery case 20 for storing electrolyte; and

(e) electrolyte is injected into the battery case 20, thereby constituting a complete battery. The electrolyte can be injected by a method known in the art, and is not described herein.

Step (a)

In a preferred embodiment of the present application, the step (a) (i.e., the step of providing (manufacturing) the battery cell of the horizontal battery) includes:

(a1) providing a frame 1 (as shown in fig. 5A, 5B, 6A, 6B), a plurality of bipolar plates 2 (as shown in fig. 7A, 7B), a plurality of positive unipolar plates 3, and a plurality of negative unipolar plates 4 (as shown in fig. 8A, 8B, the positive and negative unipolar plates are similar in appearance and constitute different plates only because the active material (i.e., positive polarity active material or negative polarity active material) coated on the surfaces thereof is different, as described in chinese patent application No. CN 202010353387.4);

(a2) stacking the bipolar plates 2, the positive unipolar plates 3, and the negative unipolar plates 4 in the frame 1 (see the U-shaped structure shown in fig. 6A and 6B) to form a plurality of battery cells 101 (see fig. 9A and 9B), with the metal terminals 31 of the positive unipolar plates 3 and the metal terminals 41 of the negative unipolar plates 4 facing outward (see fig. 2A and 2B);

(a3) mounting a pressure cover plate 5 (shown in fig. 10A and 10B) on top of the frame 1 to fix the plurality of bipolar plates 2, the plurality of positive unipolar plates 3, and the plurality of negative unipolar plates 4 in the frame 1, thereby forming a structure shown in fig. 11A and 11B; and

(a4) the metal lead-out terminal 31 of the positive monopolar plate 3 and the metal lead-out terminals 41 of the plurality of negative monopolar plates 4 shown in fig. 11A and 11B are welded to form the bus bars 32 and 42 shown in fig. 2A and 2B, respectively, and the positive and negative terminals are led out from the bus bars 32 and 42. In the finished battery, the positive and negative terminals are exposed from the top of the battery case 20 for external connection.

The following will specifically explain the steps (a1) - (a 4).

Referring to fig. 5A, 5B, preferably, the frame 1 provided in step (a1) is a frame that can be folded, generally comprising three major parts: a bottom support plate 11 and foldable wings 12 located on both sides of said bottom support plate 11. As shown in fig. 5A and 5B, before folding, the entire frame 1 has a substantially flat plate shape; as best seen in fig. 5A, notches 15 are formed at the junctions of the bottom support plate 11 and the foldable wings 12 at both sides to facilitate folding. As shown in fig. 6A and 6B, the foldable wing plate 12 can be folded to be substantially perpendicular to the bottom support plate 11 to form a substantially U-shaped structure to facilitate placement of the plurality of bipolar plates 2, the plurality of positive unipolar plates 3, and the plurality of negative unipolar plates 4 in the U-shaped cavity. As shown in fig. 5A, 5B, 6A and 6B, a plurality of through

holes

111 and 121 through which an electrolyte flows are formed in the bottom support plate 11 of the frame 1 and/or the foldable flap 12, and in the step (e), the electrolyte is introduced into the respective battery cells through the plurality of through

holes

111 and 121.

Preferably, the bipolar plate 2, the positive monopolar plate 3, and the negative monopolar plate 4 provided in step (a) are the bipolar plate, the positive monopolar plate, and the negative monopolar plate disclosed in chinese patent application No. CN 202010353387.4. For example, as shown in fig. 7A and 7B, the bipolar plate 2 includes a negative electrode plate 21, a positive electrode plate 22 and a separation seal 23 therebetween, which are integrally formed. The separation seal portion 23 helps to achieve sealing between the different battery cells 101.

In the step (a2), the plurality of bipolar plates 2, the plurality of positive unipolar plates 3, and the plurality of negative unipolar plates 4 are placed on the bottom support plate 11, and the foldable wing plate 12 is folded to a position substantially perpendicular to the bottom support plate 11, or the foldable wing plate 12 is first folded to a position substantially perpendicular to the bottom support plate 11, and then the plurality of bipolar plates 2, the plurality of positive unipolar plates 3, and the plurality of negative unipolar plates 4 are placed on the bottom support plate 11, so that the plurality of bipolar plates 2, the plurality of positive unipolar plates 3, and the plurality of negative unipolar plates 4 are positioned on the bottom support plate 11 between the foldable wing plates 12.

Preferably, the frame 1 provided in step (a1) comprises a plurality of sections 13, each section 13 having a gap 14 therebetween. In the embodiment shown in fig. 5A, 5B, 6A, 6B, the frame 1 comprises two sections 13. In practice, the number of segments 13 of the frame 1 may be determined according to the number of the battery cells 101, and generally, the number of segments 13 may be the same as the number of the battery cells 101, so that the plate in one segment 13 constitutes one battery cell 101, as described in detail below.

In the step (a2), the negative electrode plate 21 and the positive electrode plate 22 of each bipolar plate 2 are respectively located at two different but adjacent sections 13 of the frame 1, and the positive unipolar plates 3 and the negative unipolar plates 4 are respectively located at two outermost sections of the frame 1, so that in each section of the frame 1, the negative electrode plate 21 of one bipolar plate 2 and the positive electrode plate 22 or the positive unipolar plate 3 of another bipolar plate 2 form one cell 101, or the positive electrode plate 22 of one bipolar plate 2 and the negative electrode plate 21 or the negative unipolar plate 3 of another bipolar plate 2 form one cell 101, with a gap 14 between each cell 101.

For example, in the embodiment shown in fig. 5A, 5B, 6A, 6B, the frame 1 comprises two sections 13, so that it is suitable to be made as a battery with two battery cells. The bipolar plate 2, the positive monopolar plate 3, and the negative monopolar plate 4 may now be stacked in the manner shown in fig. 9A and 9B. Referring to fig. 9B (enlarged view at I of fig. 9A), the negative plate 21 of the bipolar plate 2 and the positive monopolar plate 3 form one cell (separated by a separator in the middle), i.e., the left cell 101 in fig. 9A, which accordingly will be located in the left section 13 of the frame 1; the positive plate 22 of the bipolar plate 2 and the negative unipolar plate 4 form another cell (separated in the middle by a separator), namely the cell 101 on the right in fig. 9B, which accordingly will be located in the section 13 on the right of the frame 1. It should be noted that only the plate configuration of one cell (including the positive electrode, the negative electrode and the separator therebetween) in each battery cell is described herein. In an actual battery product, there are many such battery cells within each battery cell, as shown in fig. 9A.

Similarly, if the battery has three cells, the frame correspondingly includes three sections. In one section, the negative plate of a bipolar plate and the positive plate form a single battery (separated by a diaphragm); in the second section, the positive plate of the bipolar plate forms a cell (separated by a separator) with the negative plate of the other bipolar plate; in a third section, the positive plate of the further bipolar plate and the negative unipolar plate form one cell (separated in the middle by a separator). If the cell has more than three (e.g., four, see later examples) cells, the bipolar plate, the positive unipolar plate, and the negative unipolar plate are also stacked in a similar fashion (see later examples of fig. 14A-17G for details).

Incidentally, the specific structure and stacking manner of the bipolar plate 2, the positive monopolar plate 3, and the negative monopolar plate 4 are not the focus of the present application, and those skilled in the art can use bipolar plates, positive monopolar plates, and negative monopolar plates of suitable structures and stack them in a suitable manner to form a plurality of battery cells, for example, the structures of the bipolar plate, the positive monopolar plate, and the negative monopolar plate and the stacking manner thereof disclosed in chinese patent application No. CN202010353387.4 can be used.

Preferably, in step (a3), the frame 1 and the pressure deck 5 are fixed together by their own structure. For example, in the embodiment of the present application, the frame 1 and the pressure cover plate 3 are provided with clamping structures that can be engaged with each other, so that the bipolar plates 2 and the positive and negative

unipolar plates

3 and 4 are fixed in the frame 1 in a self-locking manner by means of the clamping structures. The clamping structure comprises a hook 51 (see fig. 10A and 10B) arranged on the pressure cover plate 5, and a cover closing window 122 (see fig. 5B and 6B) arranged at the top of the frame 1 and capable of being matched with the hook 51.

More specifically, in step (a3), after the pressure cover plate 5 is placed on top of the stack of the plurality of bipolar plates 2, positive monopolar plates 3 and negative monopolar plates 4 within the frame 1, the plurality of bipolar plates 2, positive monopolar plates 3 and negative monopolar plates 4 are elastically deformed by applying pressure to the pressure cover plate 5 so that the hooks 51 enter the close-cover windows 122 of the foldable wing plates 12, and then the application of pressure is stopped, at which time the plurality of bipolar plates, positive monopolar plates and negative monopolar plates are restored from the elastic deformation so that the hooks 51 are firmly snapped into the close-cover windows 122. The self-locking fixing mode is simple and convenient to operate, and is very stable and not easy to loosen after being fixed.

As for the step (a4), the

metal terminals

31 and 41 of the positive and negative

unipolar plates

3 and 4 are respectively welded to form the bus bars, and the positive and negative terminals are led out from the bus bars, which may be performed according to a conventional technique in the art. And are not described in detail herein.

Steps (b) and (c)

The present application focuses on the concept of integrating a battery cell and a battery core by injection molding, rather than on a specific mold design. Therefore, how the mold design is performed is not described in detail in this application. Those skilled in the art will design the mold specifically according to the shape and size of the battery cell, the number of the battery cells, and the shape and size of the battery case to be formed.

In step (b), the battery cell 10 manufactured in step (a) is placed in a suitable injection mold as an embedded part.

And (c) injecting molten plastic into the injection mold, so that the molten plastic flows to surround the battery core 10, cooling and then opening the mold, thereby obtaining a structure in which the battery case 20 and the battery core 10 are combined into a whole. More specifically, in the step (C), the mold is designed such that the battery case 20 is combined with the bus bars 32, 42 of the battery cell 10 at both ends thereof, and the circulation passage P is formed between both sides of the battery cell 10 and the respective inner walls of the battery case 20 for the circulation of the electrolyte (see fig. 3B, 3C, 4B, 4C).

In the embodiment of the present application, the width of the circulation path P is 0.5 to 20 mm. The circulating channel with the width can ensure that the electrolyte can smoothly circulate in the circulating channel, does not cause overlarge integral space of the battery, and is favorable for ensuring the compactness of the structure of the battery. The width of the circulation path P can be designed by those skilled in the art within the above range according to the overall size of the battery and the flow rate of the electrolyte to be circulated when specifically designed. Preferably, the width of the circulation channel is 2-10 mm. For example, the width of the circulation channel may be 4mm, 6mm or 8 mm. The circulation channel within the above size range can effectively achieve the smooth circulation of the electrolyte therein and the minimization of the overall size of the battery.

Since the molten plastic has good fluidity, in the step (C), the molten plastic can sufficiently fill the gaps 14 between the respective battery cells 101, so that the partition walls 6 (see fig. 3C and 4C) are formed between the adjacent battery cells 101 after cooling, and the partition walls 6 can effectively separate the adjacent battery cells 101 to prevent electrolyte from flowing between the different battery cells.

Step (d)

In the step (d), the top cover 30 and the bottom cover 40, which are prepared in advance, are mounted on the top surface and the bottom surface of the battery case 20, respectively, and sealed to form the structure shown in fig. 4A to 4E, so that a sealed space is formed inside the battery case 20 for storing the electrolyte. The top cover 30 and the bottom cover 40 can be formed by a process known in the art, and the top cover 30 and the bottom cover 40 can be sealed with the battery case 20 by a conventional heat sealing or glue sealing method, which is not described in detail herein.

Referring to fig. 12A, 12B, the structure of the top cover 30 is shown. In which fig. 12A is a bottom view of the top cover 30 and fig. 12B is a sectional view H-H of fig. 12A. A plurality of relief valve mounting seats 301 are provided on the outer side of the top cover 30, and in the step (d), a relief valve 302 is mounted on each relief valve mounting seat 301. The number of the air release valve mounting seats 301 needs to be equal to the number of the battery cells, so that each battery cell has a corresponding air release valve in the finished battery, thereby enabling exhaust gas to be discharged. In the embodiment shown in fig. 12A and 12B, two air release valve mounting seats 301 are provided on the top cover 30, so that the top cover 30 is suitable for two-cell batteries.

Further, as shown in fig. 12A, the inner side of the top cover 30 is formed with a groove 303 which is fitted with the side wall of the battery case 20, and in the step (d), the groove 303 is fitted with the side wall of the battery case 20 and sealed.

Specifically, referring to fig. 3B, the upper end 201 of the sidewall of the battery case 20 has a thickness smaller than the sidewall body 202; referring again to fig. 4B and 4D, the upper end 201 is inserted into the groove 303 of the top cap 30 to form a seal, and the outer surface of the sidewall body 202 is flush with the outer surface of the top cap 30. This kind of structure not only helps realizing forming effectual, firm sealed between the lateral wall of battery case and the top cap to prevent that electrolyte from revealing, make the whole surperficial level of battery moreover.

Referring to fig. 13A, 13B, the structure of the bottom cover 40 is shown. Fig. 13A is a top view of the bottom cover 40, and fig. 13B is a cross-sectional view taken along line I-I of fig. 13A. As shown in fig. 13A and 13B, a groove 402 is formed on the inner side of the bottom cover 40 to be engaged with the sidewall of the battery case 20, and in the step (d), the groove 402 is engaged with the sidewall of the battery case 20 and sealed.

Specifically, referring to fig. 3B, the lower end 203 of the side wall of the battery case 20 has a smaller thickness than the side wall main body 202, and referring to fig. 4B and 4E, the lower end 203 is inserted into the groove 402 of the bottom cover 40 to form a seal, and the outer surface of the side wall main body 202 is flush with the outer surface of the bottom cover 40. This structure not only helps realizing forming effective, firm sealed between the lateral wall of battery shell and the bottom to prevent the electrolyte to reveal, make the whole surperficial level of battery moreover.

Step (e)

As shown in fig. 13A, 13B, the bottom cover 40 has a plurality of apertures 401 thereon, and in the step (e), the electrolyte is injected into the battery case 20 through the plurality of apertures 401. The injection method can be the prior art and is not detailed here.

Described from another perspective, a method of manufacturing a bipolar horizontal battery 100 according to the present application includes the steps of:

(i) providing a battery cell 10 (e.g., a battery cell 10 of the prior art); and

(ii) the battery core 10 is placed into an injection mold as an embedded part, a battery shell 20 is formed in the injection mold through injection molding, the battery shell 20 and the battery core 10 are combined into a whole, and a circulation channel P is formed between the battery shell and the battery core for electrolyte to flow through.

The method further comprises the following steps:

(iii) respectively installing and sealing a top cover 30 and a bottom cover 40 on the top surface and the bottom surface of the battery case 20, thereby forming a sealed space inside the battery case 20 for storing electrolyte; and

(iv) electrolyte is injected into the battery case 20, and a battery finished product is formed.

Referring to fig. 2A, in the above embodiment, the battery cell 10 includes a plurality of battery cells 101, and a gap 14 is provided between each of the battery cells 101; in the step (ii), the gaps 14 between the battery cells 101 are filled with the molten plastic, so that partition walls 6 (see fig. 4C) are formed between the adjacent battery cells 101 after cooling to separate the adjacent battery cells 101. Since the partition walls 6 are formed of the molten plastic, the molten plastic has good fluidity and can sufficiently permeate and flow into the gaps 14, and therefore, the partition walls 6 formed of the molten plastic can form good seals between the battery cells 101, thereby effectively preventing the electrolyte from flowing between different battery cells, leaking, and the like.

The present application also includes a bipolar horizontal battery 100 manufactured according to the above-described method.

A bipolar horizontal battery 100 according to the present application includes: a battery core 10 including a plurality of battery cells 101, each of the battery cells 101 having a gap 14 therebetween; and a battery case 20 integrally formed with the battery cell 10 by injection molding, and having a circulation passage P formed therebetween for the circulation of an electrolyte. The width of the circulation passage P is 0.5-20 mm. The circulating channel with the width can ensure that the electrolyte can smoothly circulate in the circulating channel, does not cause overlarge integral space of the battery, and is favorable for ensuring the compactness of the structure of the battery. Those skilled in the art can design the width of the circulation channel within the above range according to the overall size of the battery and the flow rate of the electrolyte to be circulated when designing the battery. Preferably, the width of the circulation channel is 2-10 mm. For example, the width of the circulation channel may be 4mm, 6mm or 8 mm. The circulation channel within the above size range can effectively achieve the smooth circulation of the electrolyte therein and the minimization of the overall size of the battery.

Referring to fig. 3C and 4C, the bipolar horizontal battery 100 further includes partition walls 6 integrally formed with the battery case 20 during the injection molding process and located in the gaps 14 between the battery cells 101, so as to separate the adjacent battery cells 101. Such partition walls 6 formed of molten plastic can form a good seal between the respective battery cells 101, thereby effectively preventing electrolyte from leaking, channeling, etc. between different battery cells.

Preferably, as shown in fig. 2A and 2B, the battery cell 10 includes a frame 1, a plurality of bipolar plates 2, a plurality of positive unipolar plates 3, a plurality of negative unipolar plates 4, and a pressure cover plate 5. As shown in fig. 5A, 5B, 6A, and 6B, a plurality of through

holes

111 and 121 through which an electrolyte flows are formed in the bottom surface and the side surface of the frame 1, so that the electrolyte flows into the battery cells 101 through the plurality of through

holes

111 and 121. A plurality of bipolar plates 2, a plurality of positive unipolar plates 3, and a plurality of negative unipolar plates 4 are stacked in the frame 1 (as shown in fig. 6A and 6B), and fixed by the pressure cover 5 to form the plurality of battery cells 101, and the metal lead-out terminal 31 of the positive unipolar plate 3 and the metal lead-out terminal 41 of the negative unipolar plate 4 face the outside to be welded, respectively, thereby forming

busbars

32 and 42. The positive and negative terminals of the battery may be further led out from the bus bars 32, 42.

Preferably, referring to fig. 7A and 7B, the bipolar plate 2 includes a negative electrode plate 21, a positive electrode plate 22 formed as a single body, and a separation seal 23 therebetween, wherein the separation seal 23 is used for electrically isolating different battery cells. As shown in fig. 5A, 5B, 6A, 6B, the frame 1 includes a plurality of sections 13, with gaps 14 between the sections 13. Wherein the negative plate 21 and the positive plate 22 of each bipolar plate 2 are respectively located at two different but adjacent sections 13 of the frame 1, and the positive unipolar plates 3 and the negative unipolar plates 4 are respectively located at two outermost sections 13 of the frame 1, such that in each section of the frame 1, the negative plate 21 of one bipolar plate 2 and the positive plate 22 or the positive unipolar plate 3 of another bipolar plate 2 form one cell, or the positive plate 22 of one bipolar plate 2 and the negative plate 21 or the negative unipolar plate 3 of another bipolar plate 2 form one cell 101. In short, as will be understood by those skilled in the art, as shown in fig. 9B, (one unit of) each cell is composed of positive and negative plates (and a separator therebetween). It should be noted that only the plate configuration of one cell (including the positive electrode, the negative electrode and the separator therebetween) in each battery cell is described herein. In an actual battery product, there are many such battery cells within each battery cell, as shown in fig. 9A. Since the specific structure of the battery cell is not the focus of the present application, it is not described herein in detail. See the disclosure of chinese patent application CN202010353387.4 for details.

In the above-described embodiment, the battery cells 101 have the gaps 14 therebetween (the gaps between the sections 13 of the frame 1 correspond to the gaps between the finally formed battery cells 101), so that the partition walls 6 are formed in the gaps 14 during the injection molding of the housing. Since the partition walls 6 are formed of the molten plastic, they can sufficiently occupy the gaps 14 between the respective battery cells 101, and thus can effectively separate the adjacent battery cells 101, preventing electrolyte from flowing between the different battery cells.

Referring to fig. 4A, 4B, in the embodiment of the present application, the bipolar horizontal battery 100 further includes: a top cover 30 provided on the top surface of the battery case 20, and a bottom cover 40 provided on the bottom surface of the battery case 20.

Regarding the specific structure of the top cover 30, reference can be made to fig. 12A, 12B, which are a bottom view of the top cover 30 and a sectional view H-H of fig. 12A, respectively. A plurality of air release valve mounting seats 301 are arranged on the outer side of the top cover 30, and an air release valve 302 can be mounted on each air release valve mounting seat 301. The number of the air release valve mounting seats 301 needs to be equal to the number of the battery cells, so that each battery cell has a corresponding air release valve in the finished battery, thereby enabling exhaust gas to be discharged. In the embodiment shown in fig. 12A and 12B, two air release valve mounting seats 301 are provided on the top cover 30, so that the top cover 30 is suitable for two-cell batteries.

Further, as shown in fig. 12A, the inner side of the top cover 30 is formed with a groove 303 that fits with the side wall of the battery case 20, and this groove 303 fits with the side wall of the battery case 20. Specifically, referring to fig. 3B, the upper end 201 of the sidewall of the battery case 20 has a thickness smaller than the sidewall body 202; referring again to fig. 4B and 4D, the upper end 201 is inserted into the groove 303 of the top cap 30 to form a seal, and the outer surface of the sidewall body 202 is flush with the outer surface of the top cap 30. This kind of structure not only helps realizing forming effectual, firm sealed between the lateral wall of battery case and the top cap to prevent that electrolyte from revealing, make the whole surperficial level of battery moreover.

Referring to fig. 13A and 13B, a detailed structure of the bottom cover 40 can be seen, wherein fig. 13A is a top view of the bottom cover 40, and fig. 13B is a cross-sectional view taken along line I-I of fig. 13A. As shown in fig. 13A and 13B, the bottom cover 40 has a plurality of apertures 401 corresponding to the plurality of battery cells 101, respectively, for injecting the electrolyte. In fig. 13A, 13B, the bottom cover 40 has two apertures 401 therein, and thus the bottom cover 40 is adapted to two-cell batteries.

Further, as shown in fig. 13A and 13B, a groove 402 to be fitted to the side wall of the battery case 20 is formed on the inner side of the bottom cover 40, and the groove 402 is fitted to the side wall of the battery case 20.

Specifically, referring to fig. 3B, the lower end 203 of the side wall of the battery case 20 has a smaller thickness than the side wall main body 202, and referring to fig. 4B and 4E, the lower end 203 is inserted into the groove 402 of the bottom cover 40 to form a seal, and the outer surface of the side wall main body 202 is flush with the outer surface of the bottom cover 40. And, at the junction of the battery case 20 and the bottom cover 40 (i.e., outside the above-described sealed portion), further sealing connection is performed. The specific sealing mode can adopt glue sealing or plastic sealing in the prior art. This structure not only helps realizing forming effective, firm sealed between the lateral wall of battery shell and the bottom to prevent the electrolyte to reveal, make the whole surperficial level of battery moreover.

The embodiment shown in fig. 1 to 13B as described above is an embodiment having two battery cells. As previously mentioned, the number of cells may be any number. In order to more fully explain the technical solution of the present invention, an embodiment having four battery cells is described below with reference to fig. 14A to 17G.

Wherein fig. 14A is a cross-sectional view of a battery having four battery cells, taken along J-J of fig. 14B, showing the internal structure of the battery; fig. 14B is a top view of the battery. As can be seen from fig. 14A, 14B, in this embodiment, the structures of the battery cell 10, the battery case 20, the top cover 30 and the bottom cover 40 are similar to the corresponding structures of the aforementioned two battery cells, with the main difference that:

four air release valve mounting seats 301 are arranged on the top cover 30, so that four air release valves 302 can be mounted on the top cover, one air release valve 302 corresponds to one battery cell, and therefore, gas generated in any battery cell 101 can be discharged in time when the gas reaches the valve opening pressure, and the battery is prevented from bulging.

Similarly, the bottom cover 40 has four apertures 401 thereon, and thus the electrolyte can be injected into the four battery cells 101 through the four apertures 401, respectively.

Fig. 15A and 15B illustrate the structure of the battery cell and the battery case (i.e., without the top cover and the bottom cover) in the embodiment shown in fig. 14A and 14B, wherein fig. 15B is a top view of the structure and fig. 15B is a cross-sectional view taken along K-K of fig. 15A. As can be seen from fig. 15A, 15B, a partition wall 6 is formed between any two adjacent battery cells 101. These partition walls 6 can effectively separate the adjacent battery cells 101, and prevent electrolyte from flowing between the different battery cells.

Fig. 16A and 16B show the structure of the battery cell 10 in the embodiment shown in fig. 14A and 14B, in which fig. 16A is a front view of the battery cell, and fig. 16B is a sectional view taken along L-L of fig. 16B. Fig. 16A, 16B, in this embodiment the frame 1 has four sections 13, three gaps 14 being formed between the four sections 13, and partition walls 6 being formed between the gaps 14.

Fig. 17A is similar to fig. 9A and shows a stacked structure of bipolar plates, positive unipolar plates, and negative unipolar plates in the battery cell in the embodiment shown in fig. 16A, 16B, and fig. 17B is a left side view of fig. 17. Fig. 17C to 17G are partially enlarged views of fig. 17A at positions I, II, III, IV, and V, respectively, showing a connection structure between the battery cells.

Referring to fig. 17C, which shows a partial structure of the left side of the first unit cell 101 (counted from the left end in the figure), it can be seen that (one unit of) the unit cell is composed of the positive electrode plate 3 and the negative electrode plate 21 (in the figure, "indicates" this is negative, the same below) of the first bipolar plate 2, and the separator 35 located therebetween, and the metal leading end 31 of the positive electrode plate 3 faces outward for welding into a bus bar. Slightly inside the metal terminal 31, there is a sealing land 34, which sealing land 34 is formed integrally with the battery case 20 during the injection molding process, thereby achieving a better seal.

Referring to fig. 17D, the structure of the junction of the first battery cell 101 and the second battery cell 101 (counted from the left end in the figure) is shown. As can be seen from the figure, the second battery cell 101 (one unit thereof) is composed of the positive electrode plate 22 (in the figure, "(+)" indicates that this is a positive electrode, the same applies hereinafter) of the first bipolar plate 2, the negative electrode plate 21 of the second bipolar plate 2, and the separator 35 interposed therebetween. Between the two unit cells 101, there is a separation seal 23 (i.e., the separation seal 23 formed on the bipolar plate 2 between the negative and

positive electrode plates

21 and 22 described above). The partition sealing part 23 is integrally formed with the partition wall 6 during injection molding, thereby better achieving sealing between the battery cells 101.

Referring to fig. 17E and 17F, the structure of the junction of the second and third battery cells 101 and the structure of the junction of the third and fourth battery cells 101 are shown (counted from the left end of the figure), respectively. As can be seen from fig. 17E, (a unit of) the third battery cell 101 is constituted by the positive electrode plate 22 of the second bipolar plate 2 and the negative electrode plate 21 of the third bipolar plate 2 described above with the separator 35 interposed therebetween. As can be seen from fig. 17F, (a unit of) the fourth battery cell 101 is constituted by the positive electrode plate 22 and the negative electrode plate 4 of the third bipolar plate 2 with the separator 35 interposed therebetween.

Referring to fig. 17G, the structure of the right end of the fourth battery cell 101 is shown, wherein the metal terminal 41 of the negative unipolar plate 4 faces the outside for welding into a bus bar. Slightly inside the metal terminals 41, there is a sealing land 44, which sealing land 44 is formed integrally with the battery case 20 during injection molding, thereby achieving better sealing.

It is understood by those skilled in the art that the above-mentioned embodiment with two or four battery cells is only for illustrating the technical solutions of the present application, and is not intended to limit the protection scope of the present application. According to the inventive concept provided in the present application, a person skilled in the art can design a technical solution of a battery including any number of battery cells, and refer to the disclosure of chinese patent application No. CN 202010353387.4.

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 horizontal battery (100), comprising the steps of:

(a) providing a cell (10) of a horizontal battery;

(b) placing the battery core (10) as an embedded part into an injection mold;

(c) forming a battery shell (20) in the injection mold in an injection manner, enabling the battery shell (20) to surround the battery core (10) and combining the battery shell and the battery core into a whole, wherein a circulating channel (P) is formed between the battery core (10) and the battery shell (20) for electrolyte to flow through;

(d) respectively installing and sealing a top cover (30) and a bottom cover (40) on the top surface and the bottom surface of the battery shell (20), so that a sealed space is formed inside the battery shell (20) for storing electrolyte; and

(e) injecting an electrolyte into the battery case (20).

2. The method of claim 1, wherein step (a) comprises:

(a1) providing a frame (1), a plurality of bipolar plates (2), a plurality of positive unipolar plates (3), and a plurality of negative unipolar plates (4);

(a2) stacking the bipolar plates (2), the positive unipolar plates (3), and the negative unipolar plates (4) in the frame (1) to form a plurality of battery cells (101), with the metal lead-out terminals (31) of the positive unipolar plates (3) and the metal lead-out terminals (41) of the negative unipolar plates (4) facing outward;

(a3) mounting a pressure cover plate (5) on the top of the frame (1) to fix the bipolar plates (2), the positive unipolar plates (3) and the negative unipolar plates (4) in the frame (1); and

(a4) and (3) respectively welding the metal leading-out ends (31) of the positive single-pole plates (3) and the metal leading-out ends (41) of the negative single-pole plates (4) to form bus bars (32, 42), and leading out positive and negative terminals from the bus bars (32, 42).

3. The method of claim 2, wherein,

the frame (1) is foldable and comprises a bottom support plate (11) and foldable wings (12) positioned at two sides of the bottom support plate (11), wherein the foldable wings (12) are foldable to be approximately vertical to the bottom support plate (11);

in the step (a2), the bipolar plates (2), the positive unipolar plates (3), and the negative unipolar plates (4) are placed on the bottom support plate (11), and the foldable wing plate (12) is folded to a position substantially perpendicular to the bottom support plate (11), or the foldable wing plate (12) is first folded to a position substantially perpendicular to the bottom support plate (11), and then the bipolar plates (2), the positive unipolar plates (3), and the negative unipolar plates (4) are placed on the bottom support plate (11), so that the bipolar plates (2), the positive unipolar plates (3), and the negative unipolar plates (4) are positioned on the bottom support plate (11) between the foldable wing plates (12).

4. The method of claim 2, wherein,

the bipolar plate (2) comprises a negative plate (21), a positive plate (22) and a separation sealing part (23) positioned between the negative plate and the positive plate which are formed into a whole;

the frame (1) comprises a plurality of segments (13), each segment (13) having a gap (14) between them;

in the step (a2), the negative plate (21) and the positive plate (22) of each bipolar plate (2) are respectively located at two different but adjacent sections (13) of the frame (1), and the positive unipolar plates (3) and the negative unipolar plates (4) are respectively located at two outermost sections of the frame (1), so that in each section of the frame (1), the negative plate (21) of one bipolar plate (2) and the positive plate (22) of the other bipolar plate (2) or the positive unipolar plate (3) form one cell (101), or the positive plate (22) of one bipolar plate (2) and the negative plate (21) or the negative unipolar plate (4) of the other bipolar plate (2) form one cell (101), and gaps (14) are formed between the cells (101).

5. The method according to claim 4, wherein in step (c), the gaps (14) between the battery cells (101) are filled with molten plastic such that upon cooling partition walls (6) are formed between adjacent battery cells (101) to isolate adjacent battery cells (101).

6. The method according to claim 2, wherein, in the step (c), the battery case (20) is combined with the bus bars (32, 42) of the battery core (10) at both ends thereof, and the circulation channel (P) is formed between both sides of the battery core (10) and the respective inner walls of the battery case (20) for circulation of the electrolyte.

7. A method as claimed in claim 6, wherein the width of the circulation channel (P) is 0.5-20 mm.

8. The method of claim 1, wherein,

a plurality of air release valve mounting seats (301) are arranged on the outer side of the top cover (30), and in the step (d), an air release valve (302) is mounted on each air release valve mounting seat (301);

the inner side of the top cover (30) is formed with a groove (303) which is fitted with the side wall of the battery case (20), and in the step (d), the groove (303) is fitted with the side wall of the battery case (20) and sealed.

9. The method of claim 8, wherein the upper end (201) of the sidewall of the battery case (20) has a thickness smaller than the sidewall body (202), the upper end (201) is inserted into the groove (303) of the top cap (30) to form a seal, and the outer surface of the sidewall body (202) is flush with the outer surface of the top cap (30).

10. The method according to claim 1, wherein the bottom cover (40) has a plurality of apertures (401) thereon, and in the step (e), the electrolyte is injected into the battery case (20) through the plurality of apertures (401);

the inner side of the bottom cover (40) is formed with a groove (402) to be fitted with the side wall of the battery case (20), and in the step (d), the groove (402) is fitted with the side wall of the battery case (20) and sealed.

11. The method of claim 10, wherein the lower end (203) of the sidewall of the battery case (20) has a thickness smaller than the sidewall body (202), the lower end (203) is inserted into the groove (402) of the bottom cover (40) to form a seal, and the outer surface of the sidewall body (202) is flush with the outer surface of the bottom cover (40).

12. A method according to claim 3, wherein a plurality of through holes (111, 121) for the circulation of an electrolyte are formed in the bottom support plate (11) of the frame (1) and/or the foldable flap (12), and in the step (e), the electrolyte is made to enter the respective battery cells (101) through the plurality of through holes (111, 121).

13. A method of manufacturing a bipolar horizontal battery (100), comprising:

(i) providing a battery cell (10); and

(ii) the battery core (10) is placed into an injection mold as an embedded part, a battery shell (20) is formed in the injection mold in an injection molding mode, the battery shell (20) and the battery core (10) are combined into a whole, and a circulation channel (P) is formed between the battery shell and the battery core for electrolyte to circulate.

14. The method of claim 13, further comprising:

(iii) respectively installing and sealing a top cover (30) and a bottom cover (40) on the top surface and the bottom surface of the battery shell (20), so that a sealed space is formed inside the battery shell (20) for storing electrolyte; and

(iv) and injecting electrolyte into the battery shell (20) and forming a battery finished product.

15. The method of claim 13, wherein,

the battery core (10) comprises a plurality of battery single bodies (101), and a gap (14) is formed between each battery single body (101);

in the step (ii), the gaps between the battery cells (101) are filled with the molten plastic, so that partition walls (6) are formed between the adjacent battery cells (101) after cooling to separate the adjacent battery cells (101).

16. A bipolar horizontal battery (100) manufactured according to the method of any one of claims 1-15.

17. A bipolar horizontal battery (100) comprising:

a battery core (10) including a plurality of battery cells (101), each of the battery cells (101) having a gap (14) therebetween;

a battery case (20) which is formed integrally with the battery cell (10) by injection molding and between which a circulation passage (P) is formed for the circulation of an electrolyte;

the bipolar horizontal battery (100) further comprises partition walls (6) which are integrally formed with the battery shell (20) in the injection molding process and located in gaps (14) between the battery single bodies (101), so that the adjacent battery single bodies (101) are isolated.

18. The bipolar horizontal battery (100) according to claim 17, wherein: the battery core (10) comprises a frame (1), a plurality of bipolar plates (2), a plurality of positive single-pole plates (3), a plurality of negative single-pole plates (4) and a pressure cover plate (5);

the bipolar plates (2), the positive single-pole plates (3) and the negative single-pole plates (4) are stacked in the frame (1) and fixed by the pressure cover plate (5) to form the battery cells (101), and

the metal lead-out terminal (31) of the positive monopolar plate (3) and the metal lead-out terminal (41) of the negative monopolar plate (4) face the outside to be welded, respectively, thereby forming bus bars (32, 42).

19. The bipolar horizontal battery (100) according to claim 18, wherein: the bipolar plate (2) comprises a negative plate (21), a positive plate (22) and a separation sealing part (23) positioned between the negative plate and the positive plate which are formed into a whole; the frame (1) comprises a plurality of segments (13), each segment (13) having a gap (14) between them;

wherein the negative plate (21) and the positive plate (22) of each bipolar plate (2) are respectively located in two different but adjacent sections (13) of the frame (1), and the positive unipolar plates (3) and the negative unipolar plates (4) are respectively positioned at two sections at the outermost side of the frame (1), so that in each section of the frame (1) the negative plate (21) of one bipolar plate (2) forms a cell with the positive plate (22) or positive single plate (3) of the other bipolar plate (2), or the positive plate (22) of one bipolar plate (2) and the negative plate (21) or the negative unipolar plate (4) of the other bipolar plate (2) form a single battery cell (101), and the gaps (14) are arranged among the single battery cells (101), so that partition walls (6) are formed in the gaps (14) during injection molding of the battery case (20).

20. The bipolar horizontal battery (100) according to claim 17, wherein the width of the circulation channel (P) is 0.5-20 mm.

21. The bipolar horizontal battery (100) according to claim 17, further comprising: a bottom cover (40) provided to a bottom surface of the battery case (20), wherein:

the bottom cover (40) is provided with a plurality of orifices (401) corresponding to the plurality of battery units (101) respectively for injecting electrolyte;

the inner side of the bottom cover (40) is formed with a groove (402) matched with the side wall of the battery shell (20); and is

Wherein a junction of the battery case (20) and the bottom cover (40) is hermetically connected.

22. The bipolar horizontal battery (100) according to claim 21, wherein the lower end (203) of the side wall (201) of the battery case (20) has a thickness smaller than that of the side wall main body (202), the lower end (203) is inserted into the groove (402) of the bottom cover (40) to form a seal, and the outer surface of the side wall main body (202) is flush with the outer surface of the bottom cover (40).

23. The bipolar horizontal battery (100) according to claim 18, wherein a plurality of through holes (111, 121) for the circulation of the electrolyte are formed on the bottom and the side of the frame (1) so that the electrolyte enters the battery cells (101) through the plurality of through holes (111, 121).