CN117673633A

CN117673633A - Upper cover assembly, single battery and high-capacity battery

Info

Publication number: CN117673633A
Application number: CN202310662887.XA
Authority: CN
Inventors: 陈孟奇; 刘毅; 党恒
Original assignee: Shaanxi Olympus Power Energy Co Ltd
Current assignee: Shaanxi Olympus Power Energy Co Ltd
Priority date: 2023-06-06
Filing date: 2023-06-06
Publication date: 2024-03-08

Abstract

The invention discloses an upper cover assembly, a single battery and a high-capacity battery. The upper cover assembly comprises two polar posts and a gas port positioned between the two polar posts; the improved structure is characterized by further comprising a cover plate body and two hollow components arranged on the cover plate body; both ends of the hollow member are open; the two poles are insulated from the cover plate body, and penetrate through the corresponding hollow members, and insulation is kept between the poles and the hollow members. During operation, only the hollow components on each single battery are required to be sealed and connected with the part of the cover plate body far away from the hollow components and the corresponding area of the first through hole corresponding to the hollow components on the housing, so that the tightness of the housing of the high-capacity battery is ensured, and the problem that the housing and the upper cover plate of the single battery can be directly welded by the laser welding is solved.

Description

Upper cover assembly, single battery and high-capacity battery

Technical Field

The invention belongs to the field of batteries, and particularly relates to an upper cover assembly, a single battery and a high-capacity battery.

Background

The uniformity of each single battery in the battery module is poor due to the fact that the single batteries in the battery module are different, and the cycle life of the battery module is directly limited, so that the uniformity of each single battery in the battery module is improved, and the focus and difficulty of research in the field are achieved.

In order to solve the above-described problems, the related art proposes a large-capacity battery including a case 1 and a plurality of unit cells 2 as illustrated in fig. 1 and 2; a plurality of single batteries are placed in the shell 1 in parallel, and a first through hole 3 for the single battery pole to extend out of the shell 1 is formed in the top plate of the shell 1 corresponding to the pole of each single battery 2; the shell 1 is provided with at least one sharing cavity 4 communicated with the inner cavity of each single battery 2;

as shown in fig. 1, if the sharing chamber 4 is one, when it is used to communicate with the electrolyte area in the inner cavity of each single battery 2, the electrolyte sharing of each single battery can be realized; as shown in fig. 2, when it is used to communicate with the gas zone in the inner cavity of each cell, it can be used to achieve gas balance of each cell.

As shown in fig. 3, if the number of the sharing chambers 4 is two, one of them is used to realize the electrolyte sharing of the unit cells, and the other is used to realize the gas balance of each unit cell.

Through the sharing chamber 4, each single battery can be at least in one of a unified electrolyte environment and a gas balance environment, so that the uniformity of each single battery is ensured, and the performance and the cycle life of the high-capacity battery are improved.

The tightness of the housing 1 is particularly important in order to avoid that the shared chamber remains completely isolated from the environment.

After the plurality of unit cells 2 are grouped, each first through hole 3 on the housing 1 and the upper cover assembly of the unit cell 2 corresponding to the first through hole need to be sealed and welded to ensure the sealing performance at the position. The current method is that the upper cover assembly of the outer shell and the single battery is welded by adopting a laser welding mode in the peripheral area corresponding to each first through hole 3 (the circle at a in fig. 1 is a welding track).

However, when mass-producing large-capacity batteries, if the bottoms of the individual battery cells are required to be kept at the same horizontal plane due to the existence of machining errors and assembly errors, the top of each individual battery cell (i.e., the upper cover assembly) may have uneven height, so that gaps exist between the upper cover assemblies and the outer shells of the individual battery cells in some large-capacity batteries, and there may be a false welding or even a problem that welding cannot be performed between the outer shells and the upper cover assemblies during laser welding, and the yield of the large-capacity batteries is affected.

Disclosure of Invention

In order to solve the problem that a gap exists between an upper cover component and a shell of a single battery of the existing high-capacity battery, so that virtual welding or even welding cannot exist between the shell and the upper cover component during laser welding, the invention provides the upper cover component.

The upper cover assembly comprises two polar posts and a gas port positioned between the two polar posts; the improved structure is characterized by further comprising a cover plate body and two hollow components arranged on the cover plate body;

both ends of the hollow member are open;

the two poles are insulated from the cover plate body, and penetrate through the corresponding hollow members, and insulation is kept between the poles and the hollow members.

According to the invention, two hollow members are arranged on the cover plate body of the single battery, when a plurality of single batteries are put into the high-capacity battery shell in groups, no matter whether gaps exist between the shell and the upper cover component of each single battery or the sizes of the gaps are different, only the part, far away from the cover plate body, of the hollow member on each single battery is required to be in sealing connection with the corresponding area of the first through hole corresponding to the hollow member on the shell during operation, so that the tightness of the high-capacity battery shell is ensured, and the problem that the virtual welding possibly even the welding cannot be realized when the shell and the upper cover plate of the single battery are directly welded by laser in the prior art is solved.

Further, for convenient processing and manufacturing, the hollow member is integrally formed on the cover plate body.

Further, in order to avoid the problem that the local temperature of the pole is too high to cause thermal runaway of each single battery, the pole is provided with a through groove for clamping the heat transfer pipe.

Further, in order to improve the operability and the suitability of sealing and fixing between the hollow member and the housing on each single battery, a part of the hollow member, which is far away from the cover plate body, can be bent for welding and sealing with the peripheral area of the first through hole on the high-capacity battery housing.

Further, a buffer deformation groove is formed in the side wall of the hollow member. The buffer deformation groove not only provides a certain deformation allowance for sealing and fixing, but also can be used for compensating the problem of overlarge or overlarge gap between the shell and the single battery, and can also compensate the coaxiality deviation of the single battery pole and the corresponding first through hole; meanwhile, when the large-capacity battery is subjected to external force or vibration, the buffer deformation groove has a certain buffer function, so that the reliability of sealing and fixing is ensured.

Further, knurling is carved on the outer surface of the pole. The purpose of this knurling setting is: when insulating glue is poured between the pole and the cover plate body and between the pole and the hollow member, the insulating glue can be stably attached and solidified in the insulating glue.

A second aspect of the present invention provides a unit cell including an outer can, an upper cap assembly, a lower cap assembly, and an electrode assembly; the improvement is that the upper cover assembly adopts the upper cover assembly provided in the first aspect. The upper cover assembly is adopted to ensure good sealing performance between the single battery and the external environment in the shell through the hollow component of the upper cover assembly in each single battery when the large-capacity battery with the shared cavity is assembled.

Further, in order to enable the unit cell to constitute a large-capacity cell sharing an electrolyte, a sealing mechanism is provided on the lower cap assembly, and the sealing mechanism can be opened by the electrolyte or an external force. The lower cover component with the sealing mechanism is used for providing good sealing performance for the single batteries when the large-capacity batteries are not assembled, and the sealing mechanism can be opened when the large-capacity batteries are required to be assembled, so that electrolyte areas in inner cavities of the single batteries are communicated.

Further, the gas port in the upper cover assembly is an explosion venting part, so that the shared chamber can be used as an explosion venting channel after the high-capacity battery is formed.

Further, the gas port in the upper cover assembly is a sealing mechanism, the sealing mechanism can be opened under the action of electrolyte or external force, the upper cover assembly with the sealing mechanism is used for enabling the single batteries to have good sealing performance when the large-capacity batteries are not assembled, and when the large-capacity batteries are required to be assembled, the sealing mechanism can be opened, and the sharing cavity can be used for communicating the gas areas of the inner cavities of the single batteries, so that the single batteries are in a gas balance state.

A third aspect of the present invention provides a high-capacity battery including a case and a plurality of unit cells; the plurality of single batteries are arranged side by side and integrally arranged in the shell; the top of the shell is provided with a sharing cavity;

the part, far away from the cover plate body, of the hollow component on the single battery is in sealing connection with the corresponding area of the first through hole on the shell; the pole of the single battery extends out of the shell.

According to the invention, each single battery is arranged in the shell side by side, so that the polar posts of each single battery can extend out of the first through holes on the corresponding shell, the shell and the upper cover assembly of the single battery are connected in a sealing way through the hollow member, the tightness of the large-capacity battery is ensured, each single battery is in a uniform electrolyte environment or a gas balance environment through the shared cavity in the large-capacity battery, the uniformity of each single battery is ensured, and the performance and the cycle life of the large-capacity battery are improved.

Further, on the basis of the large-capacity battery in the third aspect, when the gas port on the single battery is a through hole, the sharing chamber is integrally formed at the top of the shell, and the sharing chamber is communicated with the gas area of each single battery through the through hole of each single battery.

Further, on the basis of the large-capacity battery in the third aspect, when the gas port on the single battery is the explosion venting part, the sharing chamber is integrally formed at the top of the shell, and the sharing chamber covers the explosion venting part of each single battery, so that the gas chamber is used for discharging after the explosion venting part is broken by the thermal runaway flue gas of the single battery.

A fourth aspect of the present invention provides a high-capacity battery including a case and a plurality of unit cells; the plurality of single batteries are arranged side by side and integrally arranged in the shell; the bottom of the shell is provided with a sharing cavity for communicating the electrolyte areas of the single batteries;

A fifth aspect of the present invention provides a high-capacity battery including a case and a plurality of unit cells; the plurality of single batteries are arranged side by side and integrally arranged in the shell; the gas port in the upper cover component of the single battery is a through hole;

the shell is provided with two sharing chambers, one sharing chamber is integrally formed at the bottom of the shell and is used for communicating electrolyte areas of the inner cavities of all the single batteries; the other sharing chamber is integrally formed at the top of the shell and is used for communicating the gas areas of the inner cavities of the single batteries;

A sixth aspect of the present invention provides a high-capacity battery including a case and a plurality of unit cells; the plurality of single batteries are arranged side by side and integrally arranged in the shell; the gas port on the single battery is an explosion venting part;

the shell is provided with two sharing chambers, one sharing chamber is integrally formed at the bottom of the shell and is used for communicating electrolyte areas of the inner cavities of all the single batteries; the other sharing chamber is integrally formed at the top of the shell and covers the explosion venting part of each single battery so as to ensure that the smoke gas in thermal runaway of the single battery is discharged through the sharing chamber after bursting the explosion venting part;

Further, in order to reduce the problem of thermal runaway of each single battery caused by the local overhigh temperature of the pole, the pole with the same polarity on each single battery in the large-capacity batteries in the third to sixth aspects is clamped with a heat transfer pipe.

Drawings

Fig. 1 is a schematic diagram of a first morphological structure of a high-capacity battery according to the related art;

fig. 2 is a schematic diagram of a second morphology and structure of a high-capacity battery according to the related art;

fig. 3 is a schematic diagram of a third morphology and structure of a high-capacity battery according to the related art;

fig. 4 is a schematic structural view of the upper cover assembly provided in embodiment 1;

FIG. 5 is a cross-sectional view of a hollow member provided with a buffer deformation groove;

fig. 6 is a schematic diagram of a unit cell structure of the upper cover assembly of embodiment 2 provided with an explosion venting portion;

fig. 7 is a schematic view of a unit cell structure in which a sealing mechanism is provided to the upper cover assembly in embodiment 2;

fig. 8 is a schematic view of a large-capacity battery in example 3;

fig. 9 is a schematic structural view of the case in embodiment 3;

fig. 10 is a schematic structural view of a first cover plate in embodiment 3;

fig. 11 is a schematic structural view of the U-shaped housing in embodiment 3;

fig. 12 is a schematic view showing the structure of a single cell in which the lower cap assembly is provided with a sealing mechanism in embodiment 5;

fig. 13 is a schematic view of a large-capacity battery in example 6;

fig. 14 is a schematic structural view of the case in embodiment 6;

fig. 15 is a schematic structural view of a U-shaped housing in embodiment 6;

fig. 16 is a schematic structural view of a second cover plate in embodiment 6;

fig. 17 is a schematic view showing the structure of a large-capacity battery in example 7;

fig. 18 is a schematic structural view of a high-capacity battery case in example 7.

The reference numerals are as follows:

1-shell, 11-barrel, 12-first apron, 13-second apron, 14-U-shaped casing, 15-third apron, 16-fourth apron, 2-battery cell, 3-first through-hole, 4-sharing cavity, 5-upper cover subassembly, 51-apron body, 52-utmost point post, 521-utmost point post adapter, 522-logical groove, 53-cavity component, 54-gas mouth, 55-buffering deformation groove, 56-sealing mechanism, 57-let out and explode portion, 6-urceolus, 7-lower cover subassembly.

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" should be construed broadly in this disclosure unless otherwise specifically indicated and defined, such as: can be fixedly connected, detachably connected or integrally connected: it may also be a mechanical connection, an electrical connection, or a direct connection, or may be indirectly connected through an intermediate medium, or may be a 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 upper cover component in the invention is as follows:

the invention redesigns the upper cover component structure of the single battery, wherein the upper cover component comprises a cover plate body, two polar posts and two hollow components corresponding to the two polar post positions; one end of the hollow component is used for being in sealing connection with a region corresponding to the first through hole corresponding to the hollow component on the high-capacity battery shell, and the other end of the hollow component is in sealing connection with an upper cover component of the single battery, so that the problem that the two components are in cold joint or can not be welded when in laser fusion welding due to overlarge gaps between the shell and the upper cover components of the single batteries in some high-capacity batteries caused by processing errors and assembly errors in the mass production process of the high-capacity batteries is solved.

The area corresponding to the first through holes is a peripheral area corresponding to any one of the first through holes on the outer surface of the shell; or the corresponding area of the first through hole is the wall of the first through hole.

The upper cover component and the upper cover component used by the prior commercial square lithium ion battery are basically similar in structure and manufacturing process, and the difference is that:

two hollow components are required to be arranged on the cover plate body, and insulation between the hollow components and the pole is required to be maintained;

the pole is longer than the pole in the existing commercial square lithium ion battery, the pole can be processed to the required length during processing, the pole is also consistent with the length of the existing commercial square lithium ion pole, a pole adapter is added in a laser welding mode on the basis, and the purpose is that the pole can extend out of a large-capacity battery shell when the pole is assembled into the large-capacity battery.

The hollow member is a thin-walled tubular structure and can be respectively connected with the upper cover plate of the single battery and the shell of the high-capacity battery in a sealing way by adopting a bonding, riveting or welding mode. The horizontal cross section of the hollow member may be a rectangular or circular ring, and for a better fit with the first through hole and the pole shape, the hollow member is generally circular in cross section.

The upper cap assembly, the unit cell using the upper cap assembly, and the large-capacity battery will be specifically described with reference to several embodiments.

Example 1

As shown in fig. 4 and 8, the upper cover assembly 5 in the present embodiment includes a cover body 51, two poles 52, and a gas port 54 disposed on the cover body 51 and located between the two poles 52; two hollow members 53 are integrally formed on the cover plate body 51, and two ends of each hollow member are open; the two poles 52 are insulated from the cover plate body 51, and extend out of the high-capacity battery shell after passing through the corresponding hollow members 53, and the poles 52 are insulated from the hollow members 53; the hollow member 53 may be bent outwardly away from the cover body and sealingly connected to a peripheral region of the housing 1 corresponding to the first through hole 3.

The insulation between the two poles 52 and the cover plate body 51 and the insulation between the poles 52 and the hollow member 53 may be made by casting insulation glue or providing an insulation glue sleeve.

There are many ways of sealing the connection, for example: bonding, riveting, etc.; however, the bonding reliability is poor compared with the welding method, and the caulking method is inconvenient for assembly, so that the hollow member and the housing are generally connected in a sealing manner by welding.

In addition to integrally forming the hollow member to the cover body, in some other embodiments, the hollow member may be welded to the cover body, but this is relatively cumbersome and inefficient to manufacture.

In some other embodiments, if the portion of the hollow member 53 away from the cover body is not bent, but the end of the hollow member 53 away from the cover body is directly welded to the housing 1, the laser welding cannot be adopted, which may make the reliability and the sealing performance of the welded portion relatively weak.

In addition, the following optimizations may also be made to the upper cover assembly in this embodiment:

1. in order to avoid the problem of thermal runaway of each single battery caused by the excessively high local temperature of the pole 52, a through groove 522 for clamping the heat transfer tube is formed in the portion of the pole 52 extending out of the housing 1.

The cross section of the through groove 522 may be designed in a U-shape or a C-shape. The C-shaped through groove is provided with natural tension at the opening, so that the heat transfer pipe is convenient to install, and meanwhile, the heat transfer pipe is more tightly clamped in the through groove, so that the heat transfer effect of the heat transfer connecting piece and the heat transfer pipe is better, and the C-shaped through groove is selected as the section of the through groove in the embodiment.

2. As shown in fig. 5, the side wall of the hollow member 53 of the present embodiment is further provided with a buffer deformation groove 55. The buffer deformation groove 55 not only provides a certain deformation allowance for sealing and fixing, but also can be used for compensating the problem of being unfavorable for welding caused by overlarge gap between the shell and the single battery, and can also compensate the coaxiality deviation of the single battery pole and the corresponding first through hole; meanwhile, when the large-capacity battery is subjected to external force or vibration, the buffer deformation groove has a certain buffer function, so that the reliability of sealing and fixing is ensured.

3. In this embodiment, the outer surface of the pole may be further engraved with knurling, and when the insulating glue is poured between the pole and the cover plate body and between the pole and the hollow member, the insulating glue can be stably attached and cured therein.

In some other embodiments, instead of self-assembling the cap assembly 5, it is also possible to use welding two hollow members to the existing cap assembly, and to make the post of the final cap assembly extendable, a post adapter 521 may be added to the existing post 52 of the final cap assembly by screwing or welding to ensure that the post 52 extends out of the housing 1. The horizontal section of the pole adapter 521 may be cylindrical or square.

If a self-capping assembly is used, the post 52 may be directly formed with a through slot 522;

if a finished cap assembly is used, a through slot 522 may be formed in the pole adapter 521.

Example 2

The embodiment provides a single battery 2, the specific structure of which is shown in fig. 6 to 8, comprising an outer cylinder 6, an upper cover assembly 5, a lower cover assembly 7 and an electrode assembly;

the outer cylinder 6 is open up and down, the upper cover component 5 and the lower cover component 7 are fixed at the upper and lower open ends of the outer cylinder 6 in a welding mode, so that a sealed single battery cavity is formed, the electrode component is arranged in the single battery cavity, and the electrode component is connected with a pole in the upper cover component 5; electrolyte is arranged in the inner cavity of the single battery 2.

The upper cover assembly 5 in this embodiment adopts the same structure as in embodiment 1.

As shown in fig. 6, the gas port 52 may be a venting portion 57 of a unit cell, which may be a venting membrane or a venting valve. As shown in fig. 7, the gas port 52 may also be a sealing mechanism 56, and the sealing mechanism 56 is opened by the electrolyte or by an external force to form a through hole. The form of this sealing mechanism 56 can be found in particular in patent CN218525645U.

The structure of the single battery is similar to that of a commercial square lithium ion battery, and the difference is that a hollow member needs to be added in the upper cover assembly, and when the single battery of the embodiment is actually manufactured, two modes exist:

mode one: the improvement can be carried out on a commercially available square lithium ion battery, namely, two hollow members are directly welded on an upper cover assembly in the commercially available square lithium ion battery in a welding mode, and insulation is ensured between the pole and the hollow members by pouring insulating glue or arranging an insulating glue sleeve. However, this approach requires labor and time, and is inefficient.

Mode two: the upper cover component of the single battery needs to be manufactured again, namely, the upper cover component needs to be integrally formed with two hollow components, insulation is ensured between the pole and the hollow components by casting insulating glue or arranging an insulating glue sleeve, and a sealing mechanism is needed to be adopted for a gas port of the upper cover component under some conditions. Other parts of the single battery can be consistent with those of the commercial square lithium ion battery, and the assembly process of the single battery is basically the same as that of the commercial square lithium ion battery.

Example 3

In this embodiment, as shown in fig. 8 and 9, there is provided a large-capacity battery including a case 1, N unit cells 2 having the same structure as that of embodiment 2, N being 2 or more; the N single batteries 2 are arranged side by side and integrally arranged in the shell 1; the top of the shell 1 is provided with a sharing chamber 4; the hollow member 53 of the upper cover assembly 5 in the single battery 2, which is far away from the cover plate body, can be bent outwards and welded with the peripheral area corresponding to the first through hole 3 on the shell 1 in a sealing way; the poles of the unit cells 2 protrude from the housing 1, and insulation is maintained between the poles and the hollow member 53.

It should be noted that: in this embodiment, in order to ensure the workability of welding and the reliability after welding between the housing of the large-capacity battery and the hollow member, the housing of the unit battery is made of an aluminum material, and therefore, the hollow member and the housing of the large-capacity battery are also made of an aluminum material.

In this embodiment, the gas port on the single battery is a sealing mechanism, and the sealing mechanism can be opened under the action of electrolyte or external force, so that the gas area in the inner cavity of the single battery 2 is communicated with the sharing chamber.

It is emphasized that the exhaust valve can be arranged on the shared cavity to periodically exhaust the gas in each single battery, so that a series of problems affecting the comprehensive performance of the large-capacity battery, such as the bulge of the single battery shell, caused by the incapability of exhausting the gas, are avoided. An exhaust valve and an explosion venting membrane can be arranged on the gas chamber 8, or only the exhaust valve can be arranged; the exhaust valve can be opened manually or automatically, and the exhaust valve is opened periodically to exhaust the gas in each single battery periodically, so that a series of problems affecting the comprehensive performance of the high-capacity battery, such as the bulge of the single battery shell, caused by the incapability of exhausting the gas, are avoided. When setting up and setting up discharge valve and let out the rupture disk simultaneously, discharge valve and let out the rupture disk and be located the both ends of gas chamber, let out the rupture disk and be used for when arbitrary battery cell takes place thermal runaway, thermal runaway flue gas burst let out rupture disk and discharge gas chamber 8 for this kind of large capacity battery has higher security performance.

In order to reduce the problem of thermal runaway caused by overhigh local temperature of the polar posts of all the single batteries on the large-capacity battery, in the embodiment, the polar posts with the same polarity on all the single batteries of the large-capacity battery are clamped with heat transfer pipes.

The housing of the high capacity battery may be constructed in three forms:

1. referring to fig. 9 and 10, the housing 1 includes a cylinder 11, a first cover plate 12, and a second cover plate 13; the top and the bottom of the cylinder 11 are both open, the first cover plate 12 is fixed (welded) on the top of the cylinder 11 in a sealing way, and the second cover plate 13 is fixed (welded) on the bottom of the cylinder 11 in a sealing way;

the first cover plate 12 is integrally formed with a sharing chamber, and two sides of the sharing chamber are divided into 2N first through holes 3,2N and 3 through holes.

2. Referring to fig. 9, 10 and 11, the housing 1 includes a U-shaped case 14, a first cover plate 12, a third cover plate 15 and a fourth cover plate 16; the top, front and rear of the U-shaped housing 14 are open, the first cover plate 12 is sealingly secured (welded) to the top of the U-shaped housing 14, and the third and fourth cover plates 15, 16 are sealingly secured (welded) to the front and rear of the U-shaped housing 14, respectively.

3. Referring to fig. 9, the housing 1 includes a cylinder 11, a third cover 15, and a fourth cover 16; the front part and the rear part of the cylinder 11 are both open, a third cover plate 15 is fixed (welded) on the front part of the cylinder 11 in a sealing way, and a fourth cover plate 16 is fixed (welded) on the rear part of the cylinder in a sealing way;

the top of the cylinder 11 is integrally formed with a sharing chamber, and two sides of the sharing chamber are divided into 2N first through holes 3,2N and 3 first through holes.

In the above three cases, the cylindrical shell 11 and the U-shaped housing 14 may be spliced by welding, or may be integrally formed by casting or stamping, etc., and in order to facilitate processing while ensuring sealability, the embodiment selects an integrally formed manner.

Example 4

Referring to fig. 8, the structure of the large-capacity battery of the present embodiment is substantially identical to that of embodiment 3, except that: the gas port of the single battery is the explosion venting part, the sharing cavity covers the explosion venting part at the moment, and when the single battery is in thermal runaway, the thermal runaway smoke breaks the explosion venting port and can be discharged through the sharing cavity.

Example 5

The embodiment provides a single battery 2, the specific structure of which is shown in fig. 6, 7 and 12, comprising an outer cylinder 6, an upper cover assembly 5, a lower cover assembly 7 and an electrode assembly;

In this embodiment, a sealing mechanism is disposed on the lower cover assembly. The sealing mechanism 56 is opened by the electrolyte or by an external force to form a through hole. The form of this sealing mechanism 56 can be found in particular in patent CN218525645U.

The structure of the single battery is similar to that of a commercial square lithium ion battery, and the difference is that a hollow member needs to be added in an upper cover assembly, and a sealing mechanism needs to be added on a lower cover assembly, so that when the single battery in the embodiment is actually manufactured, two modes exist:

mode one: the improvement can be carried out on a commercially available square lithium ion battery, namely, two hollow members are directly welded on an upper cover assembly in the commercially available square lithium ion battery in a welding mode, and insulation is ensured between the pole and the hollow members by pouring insulating glue or arranging an insulating glue sleeve. Then, the lower cover assembly is perforated, and then a sealing mechanism is arranged at the opening, however, the method is labor-consuming and time-consuming, and has low efficiency.

Mode two: the upper cover component of the single battery needs to be manufactured again, namely, the upper cover component needs to be integrally formed with two hollow components, and insulation is kept between the pole and the hollow components by pouring insulating glue or arranging an insulating glue sleeve; the lower cover assembly also needs to be manufactured again, namely, a sealing mechanism is arranged on the lower cover assembly; in some cases it may also be desirable to employ a sealing mechanism for the gas port of the upper lid assembly.

Other parts of the single battery can be consistent with those of the commercial square lithium ion battery, and the assembly process of the single battery is basically the same as that of the commercial square lithium ion battery.

Example 6

As shown in fig. 13, the large-capacity battery structure of the present embodiment is basically identical to that of embodiment 3, and only one shared chamber is provided, except that: the single cell adopts the structure of example 5; the sharing cavity is arranged at the bottom of the shell and is used for communicating the electrolyte areas of the inner cavities of all the single batteries. Since each unit cell shares the electrolyte, a plurality of unit cells need to be arranged in parallel in this embodiment.

When the sealing mechanism 56 on the lower cover assembly of each single battery is opened under the action of electrolyte or external force, the electrolyte area of each single battery is communicated with the shared chamber, so that each single battery is in a common electrolyte system, and the performance and the cycle life of the high-capacity battery are improved.

The housing of the high capacity battery may be constructed in three forms:

1. referring to fig. 14 and 16, the housing 1 includes a cylinder 11, a first cover plate 12, and a second cover plate 13; the top and the bottom of the cylinder 11 are both open, the first cover plate 12 is fixed (welded) on the top of the cylinder 11 in a sealing way, and the second cover plate 13 is fixed (welded) on the bottom of the cylinder 11 in a sealing way;

the first cover plate 12 is provided with 2N first through holes 3, and the second cover plate 13 is integrally formed with a shared chamber.

2. Referring to fig. 14 and 15, the housing 1 includes a U-shaped shell 14, a first cover plate 12, a third cover plate 15, and a fourth cover plate 16; the top, front and rear of the U-shaped housing 14 are open, the first cover plate 12 is sealingly secured (welded) to the top of the U-shaped housing 14, and the third and fourth cover plates 15, 16 are sealingly secured (welded) to the front and rear of the U-shaped housing 14, respectively.

The first cover plate 12 is provided with 2N first through holes 3, and a shared chamber is integrally formed on the bottom of the u-shaped housing 14.

3. Referring to fig. 14, the housing 1 includes a cylinder 11, a third cover 15, a fourth cover 16; the front part and the rear part of the cylinder 11 are both open, a third cover plate 15 is fixed (welded) on the front part of the cylinder 11 in a sealing way, and a fourth cover plate 16 is fixed (welded) on the rear part of the cylinder in a sealing way;

the top of barrel 11 is provided with 2N first through-holes 3, and barrel 11 bottom integrated into one piece has a sharing cavity.

In the above three cases, the cylindrical body 11 and the U-shaped housing 14 may be joined together by welding, or may be integrally formed by casting or stamping, etc., and for convenience of processing while ensuring sealability, an integrally formed method is generally selected.

Example 7

As shown in fig. 17, in this embodiment, based on embodiment 6 (in which electrolyte can be shared), a sharing chamber 4 is added to the top of the housing; that is to say that the large-capacity battery of the present embodiment has two shared chambers 4 thereon.

When the gas port 54 in the upper cover assembly 5 of the single battery 2 is the sealing mechanism 56, the sealing mechanism is opened under the action of electrolyte or external force, so that the gas area in the inner cavity of the single battery 2 is communicated with the additionally-arranged shared chamber.

When the gas port 54 in the upper cover assembly 5 of the unit battery 2 is the explosion venting portion, the sharing chamber covers the explosion venting portion of each unit battery 2 to ensure that the gas generated by the thermal runaway of the unit battery is exhausted through the additionally-arranged sharing chamber after the explosion venting port is broken.

The housing of the high capacity battery may be constructed in three forms:

1. referring to fig. 18, the housing 1 includes a cylinder 11, a first cover plate 12, a second cover plate 13; the top and the bottom of the cylinder 11 are both open, the first cover plate 12 is fixed (welded) on the top of the cylinder 11 in a sealing way, and the second cover plate 13 is fixed (welded) on the bottom of the cylinder 11 in a sealing way;

referring to fig. 10, the first cover plate 12 is provided with 2N first through holes 3 and integrally formed with a shared chamber, and referring to fig. 16, the second cover plate 13 is also integrally formed with a shared chamber.

2. Referring to fig. 18, the housing 1 includes a U-shaped shell 14, a first cover plate 12, a third cover plate 15, and a fourth cover plate 16; the top, front and rear of the U-shaped housing 14 are open, the first cover plate 12 is sealingly secured (welded) to the top of the U-shaped housing 14, and the third and fourth cover plates 15, 16 are sealingly secured (welded) to the front and rear of the U-shaped housing 14, respectively.

Referring to fig. 10, the first cover plate 12 is provided with 2N first through holes 3 and integrally formed with a shared chamber, and referring to fig. 15, the bottom of the u-shaped housing 14 is also integrally formed with a shared chamber.

3. Referring to fig. 18, the housing 1 includes a cylinder 11, a third cover 15, a fourth cover 16; the front part and the rear part of the cylinder 11 are both open, a third cover plate 14 is fixed (welded) on the front part of the cylinder 11 in a sealing way, and a fourth cover plate 16 is fixed (welded) on the rear part of the cylinder in a sealing way;

the top of the cylinder 11 is provided with 2N first through holes 3 and integrally formed with a shared chamber, and the bottom of the cylinder 11 is also integrally formed with a shared chamber.

Claims

1. An upper cover assembly comprises two polar posts and a gas port positioned between the two polar posts; the novel cover plate is characterized by also comprising a cover plate body and two hollow members arranged on the cover plate body;

both ends of the hollow member are open;

2. The cover assembly of claim 1, wherein the hollow member is integrally formed with the cover body.

3. An upper cover assembly according to claim 2, wherein the pole is provided with a through slot for clamping the heat transfer tube.

4. A cap assembly according to any one of claims 1 to 3, wherein a portion of the hollow member remote from the cap body is pliable for welding sealing with a peripheral region of the first through-hole in the high capacity battery housing.

5. The cover assembly of claim 4, wherein the hollow member side wall is provided with a buffer deformation groove.

6. The cap assembly of claim 4, wherein the outer surface of the post is knurled.

7. A single battery comprises a cylinder body, an upper cover assembly, a lower cover assembly and an electrode assembly; the cover assembly according to any one of claims 1 to 6.

8. A cell according to claim 7, wherein the lower cap assembly is provided with a sealing mechanism which can be opened by the action of an electrolyte or an external force.

9. A single cell according to claim 7 or 8, wherein the gas port in the upper cap assembly is a venting portion.

10. A cell according to claim 7 or 8, wherein the gas port in the cap assembly is a sealing mechanism which can be opened by the action of an electrolyte or an external force.

11. A high capacity battery characterized by: comprising a housing and a plurality of the cells of claim 7; the plurality of single batteries are arranged side by side and integrally arranged in the shell; the top of the shell is provided with a sharing cavity;

12. The high-capacity battery as claimed in claim 11, wherein the gas ports of the single cells are through holes, the sharing chamber is integrally formed at the top of the housing, and the sharing chamber is communicated with the gas areas of the single cells through the through holes of the single cells.

13. The high-capacity battery as claimed in claim 11, wherein the gas port on the single battery is a venting portion, the sharing chamber is integrally formed at the top of the housing, and the sharing chamber covers the venting portion of each single battery to ensure that the gas chamber is exhausted after the thermal runaway flue gas of the single battery breaks through the venting portion.

14. A high capacity battery characterized by: comprising a housing and a plurality of the cells of claim 8; the plurality of single batteries are arranged side by side and integrally arranged in the shell; the bottom of the shell is provided with a sharing cavity for communicating the electrolyte areas of the single batteries;

15. A high capacity battery characterized by: comprising a housing and a plurality of the cells of claim 8; the plurality of single batteries are arranged side by side and integrally arranged in the shell; the gas port of the single battery is a through hole;

16. A high capacity battery characterized by: comprising a housing and a plurality of the cells of claim 8; the plurality of single batteries are arranged side by side and integrally arranged in the shell; the gas port on the single battery is an explosion venting part,

17. A high capacity cell as claimed in any one of claims 11 to 16, wherein said poles of the same polarity of each cell are clamped with heat transfer tubes.