CN120237354A

CN120237354A - A large capacity battery and a manufacturing method thereof

Info

Publication number: CN120237354A
Application number: CN202311827969.1A
Authority: CN
Inventors: 陈孟奇; 雷政军
Original assignee: Shuang'ao Energy Storage Technology Xi'an Co ltd
Current assignee: Shuang'ao Energy Storage Technology Xi'an Co ltd
Priority date: 2023-12-28
Filing date: 2023-12-28
Publication date: 2025-07-01

Abstract

The present invention discloses a large-capacity battery and a manufacturing method thereof. The large-capacity battery comprises a cylinder, N cover plate assemblies, N electrode assemblies, a heat transfer tube and an electrolyte, wherein N is greater than or equal to 2. The N electrode assemblies with the cover plate assemblies are installed in a cylinder, and the N electrode assemblies of the large-capacity battery are in an electrolyte system, which not only ensures that the battery has a large capacity, but also avoids the problem of a reduced cycle life of the battery module due to the consistent consumption of electrolyte and lithium ions in each single cell in the existing battery module. At the same time, the present invention can directly transfer the temperature of each electrode assembly to an external temperature control device through a heat transfer tube, thereby reducing the problem that overheating of the electrode assembly will affect the performance of the large-capacity battery. More importantly, the probability of thermal runaway is reduced by directly controlling the temperature of each electrode assembly.

Description

High-capacity battery and manufacturing method thereof

Technical Field

The invention belongs to the field of batteries, and particularly relates to a high-capacity battery and a manufacturing method thereof.

Background

In recent years, lithium ion batteries are increasingly widely used, and are important for energy storage systems such as hydraulic power generation, thermal power generation, wind power generation, solar power generation and the like, as well as electric tools, electric bicycles, electric motorcycles, electric automobiles, special equipment, special aerospace and the like.

In order to meet the use scene of large capacity, the existing battery with large capacity is to form a battery module by combining a plurality of finished single batteries in parallel, series or series-parallel. The battery modules connected in series may increase the total voltage, and the battery modules connected in parallel may increase the total capacity.

However, in the above manner, the individual battery cells in the existing battery module have differences, so that the consumption of the electrolyte and the lithium ions of the individual battery cells are different after the battery module is operated for a period of time, and the uniformity of the individual battery cells is poor, so that the cycle life of the battery module is directly limited, and on the premise of ensuring large capacity, the improvement of the uniformity of the individual battery cells in the battery module becomes important and difficult for research in the field.

Disclosure of Invention

The invention provides a high-capacity battery, which aims to solve the problem of poor uniformity of each single battery in the existing battery module.

The high-capacity battery comprises a cylinder, N cover plate components, N electrode components, a heat transfer pipe and electrolyte, wherein N is more than or equal to 2, and the upper end of the cylinder is open;

Each cover plate component comprises a cover plate body, and a positive pole column and a negative pole column which are fixed on the cover plate body in an insulating way;

The N electrode assemblies are uniformly arranged in the airtight box body along the first direction of the cylinder body, the upper part of each electrode assembly corresponds to one cover plate assembly, the positive plate and the negative plate of each electrode assembly are respectively and electrically connected with the positive pole post and the negative pole post on the cover plate assembly, the positive pole posts on each cover plate assembly are electrically connected to form a total positive pole terminal, the negative pole posts on each cover plate assembly are electrically connected to form a total negative pole terminal, the total positive pole terminal and the total negative pole terminal are in heat exchange with an external temperature control device through at least one heat transfer pipe, and electrolyte is contained in the airtight box body.

According to the high-capacity battery, the N electrode assemblies are placed in the cylinder with the upper end being open, the open end of the cylinder is sealed by the N cover plate assemblies, and all the electrode assemblies are located in one electrolyte system, so that the problem that the consumption of electrolyte and lithium ions of all the single batteries in the existing battery module is different is solved, the service life of the high-capacity battery is ensured, the electrode assemblies are located in one air pressure system, the problem that the performance of the battery module is affected due to the fact that the internal pressure of all the single batteries is different after all the single batteries run for a period of time is solved compared with the existing battery module, meanwhile, the probability that the thermal runaway problem occurs due to the fact that the air pressure in one single battery is too large in the existing battery module is solved, and the safety of the high-capacity battery is improved.

In addition, the heat transfer pipe arranged at the total positive electrode terminal and the total negative electrode terminal can directly transfer the temperature of each electrode assembly to an external temperature control device, so that the problem that the performance of the high-capacity battery is affected due to overheat of the electrode assemblies is solved, more importantly, the probability of thermal runaway is reduced due to direct temperature control of each electrode assembly, and meanwhile, the heat transfer pipe can directly heat each electrode assembly to control the water content in the electrode assembly when the high-capacity battery is manufactured.

Further, in order to ensure that the cover plate assembly can be reliably welded at the open end of the cylinder, the tightness of the sealing box body is ensured, meanwhile, short circuit risks possibly existing in mutual contact after bulge occurs in the operation process of each electrode assembly are avoided, the cylinder is provided with N-1 first partition plates at intervals along the first direction, the cylinder is divided into N placement areas of the electrode assemblies, and the N placement areas are communicated with each other.

Further, in order to solve the problem that after the cover plate assembly is placed due to the fact that the cover plate assembly is placed when the cover plate bodies and/or the open ends of the placement areas are processed, the upper surface of the cover plate body is uneven, a circle of flexible gaskets are arranged on the cover plate body of the cover plate assembly, which is close to the peripheral edges, the end faces of the open ends of the placement areas are stepped faces, a first face of each stepped face is welded with the cover plate body, a second face of each stepped face is matched with the corresponding flexible gasket, and the first face is located above the second face.

Further, the positive electrode column and the negative electrode column are respectively provided with a groove or a through hole for clamping the heat transfer tube.

Further, in order to simultaneously consider the heat transfer efficiency of the heat transfer pipe while ensuring the reliability of the installation, the heat transfer pipe is an aluminum water-cooled pipe, and in order to ensure the safety, insulation is required between the aluminum water-cooled pipe and the groove, or between the aluminum water-cooled pipe and the through hole.

Further, the explosion venting part is arranged on the closed box body. Through setting up this let out and explode portion can in time release thermal runaway flue gas when thermal runaway takes place for the large capacity battery, avoid more serious accident to take place.

Further, the sealed box body is provided with a liquid injection and exchange interface. The liquid filling and changing interface is arranged, so that liquid filling in the initial stage of the battery is facilitated, and meanwhile, the interface can be utilized to ensure the cycle life of the high-capacity battery in a mode that the capacity of the battery is attenuated to a certain degree, and the capacity of the high-capacity battery can be improved or maintained by supplementing electrolyte or lithium supplement additive or integrally replacing the electrolyte.

Further, in order to improve the cycle life of the high-capacity battery, the high-capacity battery further comprises at least one second baffle and an upper sealing cover, the second baffle is vertically arranged in the cylinder, a cavity with an open upper end is formed between the second baffle and the side wall of the cylinder, the cavity is communicated with the placement area, the upper open end of the cavity is sealed through the upper sealing cover, and electrolyte is contained in the cavity.

Further, the first direction side wall and the second direction side wall of the cylinder are provided with reinforcing ribs in hollow structures. The strength of the cylinder is improved by additionally arranging the reinforcing ribs, and meanwhile, the reinforcing cavity with the hollow structure can be used as an air cooling channel and a liquid cooling channel, so that the temperature control capability of the high-capacity battery can be improved.

Another aspect of the present invention provides a method for manufacturing the above-mentioned high-capacity battery, comprising the steps of:

Preparation of cell units

Connecting the cover plate assembly and the electrode assembly into a battery cell unit by utilizing a welding mode;

mounting the battery cell unit and forming a sealed box

Placing N electric core units into the cylinder from the open end of the cylinder, and then sealing and fixing the cover plate component in each electric core unit on the open end of the cylinder in a welding mode, wherein the cylinder and the N cover plate components form a sealed box;

Mounting heat transfer tube

At least one heat transfer tube is matched with the heat transfer tube;

Dewatering

Heating each electrode assembly by using a heat transfer tube to reduce the water content in the electrode assembly;

assembly of a total positive terminal and a total negative terminal

All positive pole posts are electrically connected to form a total positive pole terminal, and all negative pole posts are electrically connected to form a total negative pole terminal;

Injecting liquid, forming and aging.

Compared with the prior art, in order to keep smaller consistency difference of each single battery in the initial state of the battery module, the manufacturing process of the high-capacity battery needs to perform capacity-sorting operation on each single battery.

In addition, the invention can heat each electrode assembly through the heat transfer pipe, control the water content of each electrode assembly, avoid the damage to the battery caused by hydrofluoric acid generated after water contacts with electrolyte, compared with the traditional vacuum baking mode, the water removing mode does not need a special vacuum baking box, reduces the manufacturing cost of the high-capacity battery, and simultaneously improves the manufacturing efficiency of the high-capacity battery.

Drawings

Fig. 1 is a schematic diagram of the structure of a large-capacity battery according to embodiment 1;

FIG. 2 is a schematic view of the structure of the large-capacity battery with the barrel removed;

fig. 3 is a schematic diagram of a high-capacity battery according to embodiment 1;

FIG. 4 is a schematic structural view of a cylinder;

FIG. 5 is a schematic view of a cover plate assembly with a flexible gasket;

Fig. 6 is a partial structural view of the cylinder.

The reference numerals are as follows:

1-barrel, 2-apron subassembly, 3-electrode assembly, 4-heat transfer pipe, 5-apron body, 6-positive pole, 7-negative pole, 8-total positive pole, 9-total negative pole, 10-recess, 11-through-hole, 12-first baffle, 13-area of placing, 14-let out and explode portion, 15-annotate the liquid interface, 16-second baffle, 17-upper closing cap, 18-cavity, 19-flexible packing ring, 20-step face, 21-first face, 22-second face.

Detailed Description

The technical solutions of the embodiments will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only some embodiments, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden, are within the scope of the present invention based on the following examples.

Meanwhile, it should be noted that the positional or positional relationship indicated by the terms "top, bottom, inner and outer" and the like herein are based on the positional or positional relationship shown in the drawings, and are merely for convenience of description, and are not intended to indicate or imply that the apparatus or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the technical solution. Furthermore, the terms "first, second, or third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The terms "mounted, connected, and coupled" as used herein, unless otherwise specifically indicated and defined, shall be construed broadly and include, for example, any fixed, removable, or integral connection, either mechanical, electrical, or direct, or indirect via an intermediary, or any communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

The basic design idea of the invention is as follows:

The N electrode assemblies with the cover plate assemblies are arranged in the cylinder body to form a large-capacity battery, and the N electrode assemblies of the large-capacity battery are positioned under an electrolyte system, so that the large-capacity battery is ensured to have larger capacity, and the problem that the cycle life of the battery module is reduced due to the fact that electrolyte and lithium ions in each single battery are consumed consistently in the conventional battery module is solved.

Example 1

As shown in fig. 1, the high-capacity battery of the embodiment includes a cylinder 1, N cover plate assemblies 2, N electrode assemblies 3, a heat transfer tube 4, and an electrolyte, where N is greater than or equal to 2, in the embodiment, n=10, and of course, the number of N may be increased according to actual situations;

The upper end of the cylinder body 1 is open, and the cylinder body 1 can be manufactured by casting, stamping, extruding or 3D printing;

The N cover plate assemblies 2 are uniformly fixed at the open end of the cylinder 1 along the first direction of the cylinder, so that a closed box body is formed;

Specifically, the width of the N cover plate assemblies 2 and the dimension of the open end of the cylinder 1 in the first direction are adapted, and the length of the cover plate assemblies 2 and the dimension of the open end of the cylinder 1 in the second direction are adapted, so that the N cover plate assemblies 2 can seal the cylinder 1. The cover plate assembly 2 can be fixed at the open end of the cylinder body 1 in a welding mode or in a sealing glue and screw fixing mode, but the operation of the fixing and sealing mode is simpler than the operation of the fixing and sealing mode in the latter welding mode, and the sealing performance and the reliability are higher.

The first direction is the longitudinal direction of the cylinder, i.e., the X direction in fig. 1, and the second direction is the width direction of the cylinder, i.e., the Y direction in fig. 1.

As shown in fig. 2, each cover plate assembly 2 comprises a cover plate body 5, and a positive electrode post 6 and a negative electrode post 7 which are fixed on the cover plate body in an insulating manner, and the cover plate assemblies are similar to the upper cover assemblies of the square single lithium batteries of the commercial products in structure, and are different from the upper cover assemblies of the square single lithium batteries of the commercial products in that the cover plate assemblies are not provided with explosion venting films and liquid injection parts, and of course, the cover plate assemblies which are customized by manufacturers of the standard parts of the finished products of the upper cover assemblies and cancel the explosion venting films and the liquid injection parts can be selected to be used as the cover plate assemblies of the invention, and when the cover plate assemblies are customized in batches, the price of the cover plate assemblies is possibly lower than that of the standard parts of the finished products of the existing upper cover assemblies.

N electrode assemblies 3 are uniformly arranged in the sealed box body along the first direction of the cylinder body, the upper part of each electrode assembly 3 corresponds to one cover plate assembly 2, the positive plate and the negative plate of each electrode assembly 3 are respectively and electrically connected with the positive post and the negative post on the cover plate assembly, the electrode assemblies 3 are made of multiple layers of electrode plates in a winding or lamination mode, and each layer of electrode plate comprises the positive plate, the diaphragm and the negative plate.

The positive pole 6 on each cover plate component 2 is electrically connected to form a total positive pole terminal 8, the negative pole 7 on each cover plate component is electrically connected to form a total negative pole terminal 9, the total positive pole terminal 8 and the total negative pole terminal 9 exchange heat with an external temperature control device through at least one heat transfer pipe 4, and electrolyte is contained in the closed box.

The total positive electrode terminal and the total negative electrode terminal can be formed in the following three modes;

1. All positive pole posts 6 can be electrically connected through a plurality of first cables to form a total positive pole terminal 8, and all negative pole posts 7 can be electrically connected through a plurality of second cables to form a total negative pole terminal 9;

2. all positive electrode posts 6 are electrically connected through a plurality of first electric connection plates to form a total positive electrode terminal 8, and all negative electrode posts 7 are electrically connected through a plurality of second electric connection plates to form a total negative electrode terminal 9;

3. All positive poles 6 are electrically connected through a first electrical connection plate with the length corresponding to the length of the cylinder body to form a total positive pole terminal 8, and all negative poles 7 are electrically connected through a second electrical connection plate with the length corresponding to the length of the cylinder body to form a total negative pole terminal 9;

In order to achieve both conductivity and mountability, the first electric connection plate is made of an aluminum plate or a copper plate with low price and good flexibility.

The heat transfer tube can be specifically manufactured by the following modes:

1. An aluminum pipe is bent into a U-shaped structure, two parallel pipe sections are used for being respectively matched with a total positive electrode terminal 8 and a total negative electrode terminal 9, so that heat exchange between each electrode assembly and an external temperature control device is achieved, a liquid inlet and a liquid outlet of the aluminum pipe are positioned on the same side, a transmission medium in the aluminum pipe can be water, insulating oil or fluorinated liquid, and the two aluminum pipes can also be respectively matched with the total positive electrode terminal and the total negative electrode terminal.

2. Two cored heat pipes are respectively matched with a total positive terminal 8 and a total negative terminal 9, so that heat exchange between each electrode assembly and an external temperature control device is realized, the cored heat pipes are evaporation-condensation type heat exchange equipment, and heat transmission is realized by means of state change of working media in the pipes.

Since the heat transfer effect of the cored heat pipe is affected by the length of the cored heat pipe, the use of the cored heat pipe is limited when the number of electrode assemblies in a large-capacity battery is large (i.e., when the length of the large-capacity battery is long), in this embodiment, an aluminum pipe is preferably selected as the heat transfer pipe, and if insulation between the heat transfer pipe and the post can be effectively ensured, water may be preferable as a heat transfer medium flowing in the aluminum pipe from the viewpoints of heat transfer efficiency, cost, and the like.

In the present embodiment, the heat transfer pipe 4 is fitted to the total positive electrode terminal and the total negative electrode terminal in two ways:

as shown in fig. 3, grooves 10 perpendicular to the axial direction of the positive electrode column 6 and the negative electrode column 7 are formed on the positive electrode column 6 and the negative electrode column 7, a heat transfer tube 4 is clamped in the grooves 10 of all the positive electrode column 6 or the grooves 10 of the negative electrode column 7, the cross section of the grooves 10 is preferably C-shaped, and the opening end of the C-shaped has certain flexibility to tightly clamp the heat transfer tube therein;

3. as shown in fig. 1, the positive electrode post 6 and the negative electrode post 7 are respectively provided with a through hole 11, and the heat transfer tube 4 is penetrated through the through holes 11 of all the positive electrode posts 6 or the through holes 11 of all the negative electrode posts 7 through transition fit or interference fit;

In the two modes, the heat transfer tube 4 is easier to install in the groove 10 than in the through hole 11 mode, and the contact area between the heat transfer tube and the pole is larger in the through hole 11 than in the groove 10 mode, so that the heat transfer effect is better.

Since the total positive electrode terminal 8 and the total negative electrode terminal 9 are charged, insulation must be maintained between the heat transfer pipe 4 and the total positive electrode terminal 8 and between the heat transfer pipe 4 and the total negative electrode terminal 9 in order to ensure safety, and the insulation may be performed by oxidizing the heat transfer pipe or by providing an insulating layer in a region where the heat transfer pipe contacts the electrode post.

It should be noted that, as shown in fig. 4, in this embodiment, N-1 first separators 12 are disposed in the cylindrical body 1 at intervals along the first direction, the heights of the first separators 12 are identical to the heights in the cylindrical body 1, the cylindrical body 1 is divided into N electrode assembly placement areas 13, the N placement areas 13 are communicated with each other, and one electrode assembly is disposed between every two adjacent first separators 12.

The first separator 12 is provided for four purposes:

The first partition plate 12 is arranged to facilitate the welding of the cover plate assembly 2 at the open end of the cylinder body 1, and the periphery of each cover plate assembly 12 can be welded with the upper edges of the two side walls of the cylinder body 1 in the first direction and the upper edges of the two adjacent first partition plates 12 to realize fixed sealing, in some other embodiments, the width direction edge of the cover plate assembly 2 can also be directly welded with the upper edges of the two side walls of the cylinder body 1 in the first direction, and then the edges of the two adjacent cover plate assemblies 2 in the length direction are directly welded and sealed, but compared with the case that the first partition plates are arranged for welding and sealing in the embodiment, the welding sealing performance and reliability are higher.

Secondly, the arrangement of the first separator 12 can avoid the problem of short circuit possibly caused by swelling of the two electrode assemblies, so that the safety is higher;

and thirdly, heat of the electrode assembly can be directly transferred to the cylinder body 1 through the first separator 12, so that the heat dissipation effect of the electrode assembly is improved.

Fourth, the arrangement of the first partition plate 12 can improve the overall strength of the cylinder body, so that the pressure bearing capacity of the cylinder body is stronger.

The first separator 12 may be disposed in the cylinder 1 by integral molding, or may be fixed in the cylinder 1 by welding, and from the viewpoint of facilitating processing and cost control, the first separator is disposed in the cylinder by integral molding in this embodiment.

The placement areas 13 may be communicated with each other by forming a channel with a larger caliber at the bottom of each first separator 12 to ensure that each electrode assembly is under one electrolyte system, or forming a plurality of through holes in each first separator 12 to ensure that each electrode assembly is under one electrolyte system.

In order to prevent the thermal runaway of the large-capacity battery under extreme conditions from happening, the thermal runaway flue gas can be timely discharged out of the sealed box body, so that more serious dangerous accidents are avoided, the sealed box body of the large-capacity battery is further provided with the explosion venting part 14, and the explosion venting part 14 can be a commercially available explosion venting valve or an explosion venting film fixedly sealed on a pipe fitting.

In this embodiment, the sealed box of the high-capacity battery is further provided with the liquid filling and changing interface 15, and by setting the liquid filling and changing interface 15 to cooperate with external liquid filling and changing equipment, the liquid filling in the initial stage of the battery is facilitated, and meanwhile, the interface can be utilized to ensure the cycle life of the high-capacity battery in a manner that the capacity of the battery is attenuated to a certain extent by supplementing electrolyte or lithium supplement additive to the high-capacity battery or integrally changing the electrolyte, and the like, so that the capacity can be improved or maintained. It should be noted that the interface needs to be kept in a blocking state during the operation of the battery, so as to ensure the tightness of the high-capacity battery.

Based on the description of the structure of the large-capacity battery, a method for manufacturing the large-capacity battery will be described in detail:

Step 1, preparing an electric core unit

The cover plate component 2 and the electrode component 4 are connected into a cell unit by welding;

step 2, installing the battery cell unit and forming a sealed box body

Placing N electric core units into the cylinder 1 from the open end of the cylinder 1, and then sealing and fixing the cover plate component 2 in each electric core unit on the open end of the cylinder 1 in a welding mode, wherein the cylinder 1 and the N cover plate components 2 form a sealed box;

step 3, installing a heat transfer tube

Two parallel pipe sections of a U-shaped heat transfer pipe 4 are respectively arranged in grooves 10 or through holes 11 of all positive pole columns 6 and all negative pole columns 7;

Step 4, removing water

The heat is transferred to each electrode assembly through the heat transfer pipe to heat, so that the water content in the electrode assembly is controlled to reach a safe limiting value, the damage of hydrofluoric acid generated after water is contacted with electrolyte to a battery is avoided, dynamic nitrogen negative pressure is needed to be provided in the water removal process, and the negative pressure can instantly take away vapor formed by vaporization;

step 5, assembling the total positive terminal and the total negative terminal

All positive poles 6 are electrically connected to form a total positive pole terminal 8, and all negative poles 7 are electrically connected to form a total negative pole terminal 9, wherein the total positive pole terminal 8 is actually the positive pole of the high-capacity battery, and the total negative pole terminal 9 is actually the negative pole of the high-capacity battery;

Step 6, injecting liquid

The electrolyte filling and changing equipment is in butt joint with the electrolyte filling and changing interface, electrolyte is filled into the sealed box body, and the amount of the electrolyte filled needs that the pole piece of each electrode assembly can fully infiltrate the electrolyte;

Step 7, formation

Charging to 3.4V with constant current of 0.1C, charging to current of 0.01C at constant voltage of 3.4V, and standing for 30min;

Discharging to 2.5V at constant current of 0.1C, and standing for 30min;

Then charging to 3.4V with 0.2C constant current, charging to 0.01C current with 3.4V constant voltage, and standing for 30min. The formation process can form a complete SEI film on each electrode assembly in the high-capacity battery, so that the high-capacity battery has more stable circulation capacity;

Step 8, aging

The high-capacity battery is placed for 24 to 72 hours in an environment with the temperature of 40 to 50 ℃, so that the aging treatment of the high-capacity battery is finished, and the manufacturing of the high-capacity battery is finished.

Compared with the prior battery module, the manufacturing process of the high-capacity battery of the invention has smaller consistency phase difference of each single battery when the battery module is in the initial state, and needs to perform capacity separation operation on each single battery, in the invention, a plurality of electrode assemblies are directly arranged in one sealed box body, and each electrolytic assembly is positioned in a unified electrolyte system, so that the capacity-dividing and sorting work is not needed, the capacity of a high-capacity battery is improved, and the manufacturing efficiency of the battery is also improved.

Example 2

The large-capacity battery structure in this embodiment is different from that in embodiment 1 in the following points:

1. As shown in fig. 4, at least one second partition 16 and an upper cover 17 are further disposed in the barrel 1, a chamber 18 with an open upper end can be formed between the second partition 16 and the side wall of the barrel 1, the upper cover 17 is fixed on the top of the chamber 18 by welding, more sufficient electrolyte can be provided in the high-capacity battery in the chamber, and the chamber needs to be communicated with each placement area, so that the design has a certain help to improve the cycle life of the high-capacity battery.

In this embodiment, the upper cover and the cover plate body may be integrally formed, so that the open end of the cylinder and the top of the chamber may be sealed at one time, and the welding process is reduced.

2. As shown in fig. 5 and 6, in order to compensate for the problem that the upper surface of the cover plate body is uneven after the cover plate assembly is placed due to the fact that the cover plate bodies and/or the open ends of each placement area are processed, a circle of flexible gaskets 19 are arranged on the cover plate body 5 of the cover plate assembly 2 near the peripheral edge, the end face of the open end of each placement area 13 is a step face 20, a first face 21 of the step face 20 is welded with the cover plate body 5, a second face 22 of the step face 20 is matched with the flexible gaskets 19, and the first face 21 is located above the second face 22.

3. In this embodiment, the liquid filling and changing interface can be designed as a multifunctional interface, so that the liquid filling and changing interface can be in butt joint with liquid filling and changing equipment, and also can be in butt joint with equipment for providing dynamic nitrogen negative pressure.

4. Because more electrolyte is stored in the large-capacity battery, in order to reduce the probability that the electrolyte can burn in a large area in the box body when thermal runaway occurs, the explosion venting part is preferably arranged at the position of the barrel body close to the bottom in the embodiment, once the electrolyte in the sealed box body can be discharged out of the sealed box body when thermal runaway occurs, and then the thermal runaway flue gas is discharged outwards again, so that the safety of the large-capacity battery can be improved.

5. The first direction side wall and the second direction side wall of the cylinder body 1 are respectively provided with a reinforcing rib with a hollow structure. The strength of the cylinder is improved by additionally arranging the reinforcing ribs, and meanwhile, the reinforcing cavity with the hollow structure can be used as an air cooling channel and a liquid cooling channel, so that the temperature control capability of the high-capacity battery can be further improved.

Claims

1. A high-capacity battery is characterized by comprising a cylinder, N cover plate assemblies, N electrode assemblies, a heat transfer tube and electrolyte, wherein N is more than or equal to 2;

The upper end of the cylinder body is open;

N cover plate components are uniformly fixed at the open end of the cylinder body along the first direction of the cylinder body, so that a closed box body is formed;

The N electrode assemblies are uniformly arranged in the closed box body along the first direction of the cylinder body, the upper part of each electrode assembly corresponds to one cover plate assembly, and the positive electrode plate and the negative electrode plate of each electrode assembly are respectively and electrically connected with the positive electrode post and the negative electrode post on the cover plate assembly;

The positive pole column on each cover plate component is electrically connected to form a total positive pole terminal, and the negative pole column on each cover plate component is electrically connected to form a total negative pole terminal;

electrolyte is contained in the closed box body.

2. A high-capacity battery as set forth in claim 1, wherein said can is provided with N-1 first separators at intervals along said first direction so as to divide the can into N placement areas of the electrode assemblies, and the N placement areas are communicated with each other.

3. The high-capacity battery as claimed in claim 2, wherein a ring of flexible gasket is arranged on the cover plate body of the cover plate assembly near the peripheral edge, the end face of the open end of the placement area is a step face, the first face of the step face is welded with the cover plate body, the second face of the step face is matched with the flexible gasket, and the first face is located above the second face.

4. The high-capacity battery as claimed in claim 2, wherein the positive electrode post and the negative electrode post are respectively provided with a groove or a through hole for clamping the heat transfer tube.

5. The high-capacity battery as recited in claim 4, wherein the heat transfer pipe is an aluminum water-cooled pipe, and insulation is maintained between the aluminum water-cooled pipe and the groove or between the aluminum water-cooled pipe and the through hole.

6. The high-capacity battery as claimed in claim 5, wherein the explosion venting portion is provided on the sealed case.

7. The high-capacity battery as claimed in claim 6, wherein the sealed case is provided with a liquid filling and exchanging interface.

8. A high-capacity battery as in any one of claims 2 to 7, further comprising at least one second separator and an upper cover, wherein the second separator is vertically installed in the cylinder, a chamber with an upper opening is formed between the second separator and the side wall of the cylinder, the chamber is communicated with the placement area, the upper opening end of the chamber is sealed by the upper cover, and electrolyte is contained in the chamber.

9. The high-capacity battery as claimed in claim 8, wherein the first-direction side wall and the second-direction side wall of the cylinder are provided with reinforcing ribs having a hollow structure.

10. A method of manufacturing a high-capacity battery according to claim 1, comprising the steps of: