Upper cover assembly, single cell and large-capacity battery

Abstract

The present invention discloses a top cover assembly, a single cell, and a large-capacity battery. The top cover assembly includes two poles and a gas port located between the two poles. The improvement is that it also includes a cover body and two hollow members disposed on the cover body. Both ends of the hollow members are open. The two poles are insulated from the cover body and pass through their respective hollow members, and the poles and hollow members are insulated from each other. During operation, only the portion of the hollow member on each single cell away from the cover body and the area corresponding to the corresponding first through hole on the outer shell need to be sealed and connected. This ensures the sealing of the large-capacity battery outer shell and solves the problem of cold welding or even impossible welding that may occur when directly laser welding the outer shell and the single cell upper cover.

Description

Technical Field

[0001] The present invention belongs to the field of batteries, and in particular relates to an upper cover assembly, a single cell and a large-capacity battery. Background Art

[0002] There are differences among the individual cells in existing battery modules, resulting in poor uniformity of the individual cells in the battery module, which in turn directly leads to limited cycle life of the battery module. Therefore, how to improve the uniformity of the individual cells in the battery module has become the focus and difficulty of research in this field.

[0003] In order to solve the above problems, the related art proposes a large-capacity battery, such as Figure 1 and 2 The large-capacity battery comprises a housing 1 and a plurality of single cells 2; the multiple single cells are placed in parallel in the housing 1, and a first through hole 3 is provided on the top plate of the housing 1 corresponding to the pole of each single cell 2, for allowing the pole of the single cell to extend out of the housing 1; the housing 1 is provided with at least one shared chamber 4 communicating with the inner cavity of each single cell 2;

[0004] like Figure 1 As shown, if there is only one shared chamber 4, when it is used to communicate with the electrolyte area in the inner cavity of each single battery 2, the electrolyte of each single battery can be shared; Figure 2 As shown, when it is used to communicate with the gas area in the inner cavity of each single cell, it can be used to achieve gas balance in each single cell.

[0005] like Figure 3 As shown, if there are two shared chambers 4, one of them is used to realize electrolyte sharing among the single cells, and the other is used to realize gas balance among the single cells.

[0006] The shared chamber 4 allows each single cell to be in at least one of a unified electrolyte environment and a gas balance environment, thereby ensuring the uniformity of each single cell and improving the performance and cycle life of the large-capacity battery.

[0007] In order to prevent the shared chamber from being completely isolated from the external environment, the sealing performance of the housing 1 is particularly important.

[0008] After the multiple cells 2 are grouped, each first through hole 3 on the housing 1 and the corresponding upper cover assembly of the cell 2 need to be sealed and welded to ensure the sealing at that location. The current method is to weld the housing and the upper cover assembly of the cell by laser welding in the surrounding area corresponding to each first through hole 3 ( Figure 1 The circle at A is the welding track).

[0009] However, when mass-producing large-capacity batteries, due to the existence of processing errors and assembly errors, if it is necessary to ensure that the bottoms of each single cell are at the same level, the tops of each single cell (i.e., the upper cover assembly) will have uneven heights, resulting in gaps between the upper cover assembly and the outer shell of individual single cells in some large-capacity batteries. As a result, there may be cold welds between the outer shell and the upper cover assembly during laser welding, or even problems with welding being impossible, which affects the yield of large-capacity batteries. Summary of the Invention

[0010] In order to solve the problem that there is a gap between the upper cover assembly and the outer shell of the single cell of the existing large-capacity battery, which may cause a cold weld between the outer shell and the upper cover assembly during laser welding, or even the problem that welding cannot be performed, the present invention provides an upper cover assembly on the one hand.

[0011] The upper cover assembly includes two poles and a gas port located between the two poles; the improvement is that it also includes a cover body and two hollow components arranged on the cover body;

[0012] Both ends of the hollow member are open;

[0013] The two poles are both insulated from the cover plate body and are passed through the corresponding hollow components, and insulation is maintained between the poles and the hollow components.

[0014] The present invention provides two hollow components on the cover body of the single cell. When multiple single cells are grouped and placed in a large-capacity battery housing, regardless of whether there is a gap between the housing and the upper cover assembly of each single cell, or whether the gap sizes are different, during operation, it is only necessary to seal and connect the portion of the hollow component on each single cell away from the cover body and the area corresponding to the corresponding first through hole on the housing, thereby ensuring the sealing of the large-capacity battery housing and solving the problem of cold welding or even failure to weld that may occur when the housing and the upper cover of the single cell are directly laser-welded in the existing solution.

[0015] Furthermore, in order to facilitate processing and manufacturing, the above-mentioned hollow component is integrally formed on the cover body.

[0016] Furthermore, in order to avoid the problem of thermal runaway of each single battery due to excessively high local temperature of the pole, a through groove for clamping the heat transfer tube is opened on the above-mentioned pole.

[0017] Furthermore, in order to improve the operability and adaptability of the sealing and fixing between the hollow component and the shell on each single battery, a portion of the above-mentioned hollow component away from the cover body can be bent for welding and sealing with the peripheral area of ​​the first through hole on the large-capacity battery shell.

[0018] Furthermore, a buffer deformation groove is provided on the side wall of the hollow member. This buffer deformation groove not only provides a certain deformation margin during sealing and fixing, which can be used to compensate for the problem of excessive or insufficient gap between the shell and the single battery, but also compensates for the coaxial deviation between the single battery terminal and the corresponding first through hole. At the same time, when the large-capacity battery is subjected to external force or self-vibration, the buffer deformation groove itself has a certain buffering effect, ensuring the reliability of sealing and fixing.

[0019] Furthermore, the outer surface of the pole is engraved with knurling, which is provided for the purpose of ensuring that when insulating glue is poured between the pole and the cover body, or between the pole and the hollow component, the insulating glue can be stably adhered and solidified therein.

[0020] A second aspect of the present invention provides a single cell battery comprising an outer casing, an upper cover assembly, a lower cover assembly, and an electrode assembly. The improvement is that the upper cover assembly utilizes the upper cover assembly provided in the first aspect. This upper cover assembly is used to ensure good sealing between the cells within the outer casing and the external environment when assembling large-capacity batteries with a shared chamber, using the hollow components of the upper cover assembly within each cell.

[0021] Furthermore, to enable the cells to be assembled into a large-capacity battery sharing electrolyte, the lower cover assembly is equipped with a sealing mechanism that can be opened by the action of electrolyte or external force. The lower cover assembly with a sealing mechanism ensures that the cells themselves are well sealed when not assembled into a large-capacity battery. When a large-capacity battery is assembled, the sealing mechanism can be opened, allowing the electrolyte areas within the individual cells to communicate.

[0022] Furthermore, the gas port in the upper cover assembly is an explosion venting portion, so after forming a large-capacity battery, the shared chamber can be used as an explosion venting channel.

[0023] Furthermore, the gas port in the above-mentioned upper cover assembly is a sealing mechanism, which can be opened under the action of electrolyte or external force. The upper cover assembly with a sealing mechanism is designed to ensure that the single cell itself has good sealing properties when a large-capacity battery is not assembled. When a large-capacity battery needs to be assembled, the sealing mechanism can be opened, and the shared chamber can connect the gas areas in the inner cavity of each single cell, so that each single cell is in a gas balance state.

[0024] A third aspect of the present invention provides a large-capacity battery, comprising a housing and a plurality of single cells; the plurality of single cells are arranged side by side and integrally disposed within the housing; a shared chamber is disposed on the top of the housing;

[0025] The portion of the hollow component on the single battery away from the cover body is sealed and connected to the area corresponding to the first through hole on the shell; the pole of the single battery extends out of the shell.

[0026] The present invention installs the single cells side by side in the shell, ensuring that the poles of the single cells can extend out of the first through holes on the corresponding shells, and seals the shell and the upper cover assembly of the single cells through a hollow component, thereby ensuring the sealing of the large-capacity battery. In addition, the shared chamber in the large-capacity battery places the single cells in a unified electrolyte environment or gas balance environment, thereby ensuring the uniformity of the single cells and improving the performance and cycle life of the large-capacity battery.

[0027] Furthermore, based on the large-capacity battery of the third aspect, when the gas port on the single cell is a through hole, the shared chamber is integrally formed on the top of the shell, and the shared chamber is connected to the gas area of ​​each single cell through the through hole of each single cell.

[0028] Furthermore, based on the large-capacity battery of the third aspect, when the gas port on the single cell is an explosion vent, the shared chamber is integrally formed on the top of the shell, and the shared chamber covers the explosion vent of each single cell to ensure that the smoke from thermal runaway of the single cell breaks through the explosion vent and is discharged through the gas chamber.

[0029] A fourth aspect of the present invention provides a large-capacity battery comprising a housing and a plurality of single cells; the plurality of single cells are arranged side by side and integrally disposed within the housing; a shared chamber is provided at the bottom of the housing for connecting the electrolyte areas of the single cells;

[0030] The portion of the hollow component on the single battery away from the cover body is sealed and connected to the area corresponding to the first through hole on the shell; the pole of the single battery extends out of the shell.

[0031] A fifth aspect of the present invention provides a large-capacity battery, comprising a housing and a plurality of single cells; the plurality of single cells are arranged side by side and integrally disposed within the housing; the gas port in the upper cover assembly of the single cells is a through hole;

[0032] The housing is provided with two shared chambers, one of which is integrally formed at the bottom of the housing and is used to connect the electrolyte areas of the inner cavities of the individual cells; the other shared chamber is integrally formed at the top of the housing and is used to connect the gas areas of the inner cavities of the individual cells;

[0033] The portion of the hollow component on the single battery away from the cover body is sealed and connected to the area corresponding to the first through hole on the shell; the pole of the single battery extends out of the shell.

[0034] A sixth aspect of the present invention provides a large-capacity battery, comprising a housing and a plurality of single cells; the plurality of single cells are arranged side by side and integrally disposed within the housing; the gas vents on the single cells serve as explosion vents;

[0035] The housing is provided with two shared chambers, one of which is integrally formed at the bottom of the housing and is used to connect the electrolyte areas of the inner cavities of each single cell; the other shared chamber is integrally formed at the top of the housing and covers the explosion vents of each single cell to ensure that the smoke from thermal runaway of the single cell breaks through the explosion vent and is discharged through the shared chamber;

[0036] The portion of the hollow component on the single battery away from the cover body is sealed and connected to the area corresponding to the first through hole on the shell; the pole of the single battery extends out of the shell.

[0037] Furthermore, in order to reduce the problem of thermal runaway of each single cell due to excessively high local temperature of the pole, a heat transfer tube is mounted on the poles of each single cell with the same polarity in the large-capacity batteries of the third to sixth aspects above. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the first structural form of a large-capacity battery proposed in the related art of the background technology;

[0039] Figure 2 A schematic diagram of the second structural form of a large-capacity battery proposed in the related art of the background technology;

[0040] Figure 3 A schematic diagram of the third structural form of a large-capacity battery proposed in the related art of the background technology;

[0041] Figure 4 A schematic structural diagram of the upper cover assembly provided in Example 1;

[0042] Figure 5 A cross-sectional view of a hollow component provided with a buffer deformation groove;

[0043] Figure 6 This is a schematic diagram of the structure of a single battery with an explosion venting portion provided on the upper cover assembly in Example 2;

[0044] Figure 7 A schematic diagram of the structure of a single battery with a sealing mechanism provided on the upper cover assembly in Example 2;

[0045] Figure 8 Schematic diagram of a large-capacity battery in Example 3;

[0046] Figure 9 Schematic diagram of the structure of the housing in Example 3;

[0047] Figure 10 This is a schematic structural diagram of the first cover plate in Example 3;

[0048] Figure 11 Schematic diagram of the structure of the U-shaped shell in Example 3;

[0049] Figure 12 A schematic diagram of the structure of a single battery with a sealing mechanism provided on the lower cover assembly in Example 5;

[0050] Figure 13 Schematic diagram of a large-capacity battery in Example 6;

[0051] Figure 14 Schematic diagram of the structure of the housing in Example 6;

[0052] Figure 15 Schematic diagram of the structure of the U-shaped shell in Example 6;

[0053] Figure 16 This is a schematic structural diagram of the second cover plate in Example 6;

[0054] Figure 17 Schematic diagram of the large-capacity battery structure in Example 7;

[0055] Figure 18 Schematic diagram of the structure of the large-capacity battery housing in Example 7.

[0056] The reference numerals are as follows:

[0057] 1-shell, 11-cylinder, 12-first cover, 13-second cover, 14-U-shaped shell, 15-third cover, 16-fourth cover, 2-single battery, 3-first through hole, 4-shared chamber, 5-upper cover assembly, 51-cover body, 52-pole, 521-pole adapter, 522-through groove, 53-hollow member, 54-gas port, 55-buffer deformation groove, 56-sealing mechanism, 57-explosion venting part, 6-outer cylinder, 7-lower cover assembly. DETAILED DESCRIPTION

[0058] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in the embodiments. Obviously, the embodiments described are only some embodiments, not all embodiments. Based on the following embodiments, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this invention.

[0059] At the same time, it should be noted that the terms "top, bottom, inner, and outer" used herein to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the technical solution. Furthermore, the terms "first, second, or third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0060] Unless otherwise specified or limited, the terms "mounted, connected, and connected" in this disclosure should be understood broadly. For example, they may refer to fixed, removable, or integral connections. They may also refer to mechanical, electrical, or direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this disclosure.

[0061] The basic design idea of ​​the upper cover assembly in the present invention is:

[0062] The present invention redesigns the structure of the upper cover assembly of the single cell battery, which includes a cover plate body, two poles, and two hollow components corresponding to the positions of the two poles; one end of the hollow component is used to be sealed and connected to the area corresponding to the corresponding first through hole on the large-capacity battery shell, and the other end is sealed and connected to the upper cover assembly of the single cell battery, thereby solving the problem of excessive gap between the shell and the upper cover assembly of each single cell of some large-capacity batteries caused by processing errors and assembly errors during the mass production of large-capacity batteries, resulting in poor welding or failure to weld the two during laser welding.

[0063] The area corresponding to the first through hole is the peripheral area on the outer surface of the housing corresponding to any one of the first through holes; or the area corresponding to the first through hole is the wall of the first through hole.

[0064] The structure and manufacturing process of the upper cover assembly of the present invention are basically similar to those of the upper cover assembly used in existing commercially available square lithium-ion batteries. The differences are:

[0065] Two hollow components need to be set on the cover body, and the hollow components need to be insulated from the poles;

[0066] The pole needs to be longer than the pole in the existing commercially available square lithium-ion battery. It can be processed to the required length during processing, or it can be the same length as the existing commercially available square lithium-ion pole. On this basis, a pole adapter is added by laser welding. The purpose is to enable the pole to extend out of the large-capacity battery shell when assembled into a large-capacity battery.

[0067] The hollow member is generally a thin-walled, tubular structure that can be sealed to the upper cover of the single cell and the outer casing of the large-capacity battery by bonding, riveting, or welding. The horizontal cross-section of the hollow member can be rectangular or circular. To better match the shape of the first through-hole and the terminal, the hollow member cross-section is typically circular.

[0068] The following describes in detail the upper cover assembly, the single cell using the upper cover assembly, and the large-capacity battery in combination with several embodiments.

[0069] Example 1

[0070] like Figure 4 and Figure 8 As shown, in this embodiment, the upper cover assembly 5 includes a cover body 51, two poles 52 and a gas port 54 arranged on the cover body 51 and located between the two poles 52; two hollow components 53 are integrally formed on the cover body 51, and both ends of the hollow components are open; the two poles 52 are insulated from the cover body 51, and extend out of the large-capacity battery shell after passing through their respective corresponding hollow components 53, and insulation is maintained between the poles 52 and the hollow components 53; the part of the hollow component 53 away from the cover body can be bent outward and sealed and connected to the peripheral area corresponding to a first through hole 3 on the shell 1.

[0071] The insulation between the two poles 52 and the cover body 51 and between the poles 52 and the hollow member 53 can be maintained by pouring insulating glue or providing an insulating rubber sleeve.

[0072] There are many ways to seal the connection, such as bonding, riveting, etc. However, compared with welding, bonding has poor reliability and riveting is not convenient for assembly. Therefore, welding is usually used to seal the hollow component to the shell.

[0073] In addition to integrally forming the hollow component on the cover body, in some other embodiments, the hollow component can be fixed to the cover body by welding. However, compared with the integral molding method, this method is more complicated to process and less efficient.

[0074] In some other embodiments, if the portion of the hollow component 53 away from the cover body is not bent, but the end of the hollow component 53 away from the cover body is directly welded to the outer shell 1, laser welding cannot be used, which may make the reliability and sealing of the welding part relatively weak.

[0075] In addition, the upper cover assembly of this embodiment can also be optimized as follows:

[0076] 1. In order to prevent the problem of thermal runaway of each battery cell due to local overheating of the pole 52, the portion of the pole 52 extending out of the housing 1 is provided with a through slot 522 for clamping a heat transfer tube.

[0077] The cross section of the through groove 522 can be designed to be U-shaped or C-shaped. Since the C-shaped through groove has natural tension at the opening, it is convenient for installing the heat transfer tube and helps to more tightly clamp the heat transfer tube into the through groove, thereby improving the heat transfer effect between the heat transfer connector and the heat transfer tube. Therefore, in this embodiment, the C-shaped cross section is selected as the through groove.

[0078] 2. If Figure 5As shown, in this embodiment, a buffer deformation groove 55 is further provided on the side wall of the hollow member 53. This buffer deformation groove 55 not only provides a certain deformation margin for sealing and fixing, which can be used to compensate for the problem of welding problems caused by excessive gaps between the housing and the single battery, but also compensates for the coaxial deviation between the single battery terminal and the corresponding first through hole. At the same time, when the large-capacity battery is subjected to external forces or self-vibration, the buffer deformation groove itself has a certain buffering effect, ensuring the reliability of sealing and fixing.

[0079] 3. In this embodiment, the outer surface of the pole can also be engraved with knurling, so that when the insulating glue is poured between the pole and the cover body, and between the pole and the hollow component, the insulating glue can be stably adhered and solidified therein.

[0080] In some other embodiments, in addition to making a self-made upper cover assembly 5, two hollow components may be welded to an existing finished upper cover assembly. To allow the pole of the finished upper cover assembly to extend, a pole adapter 521 may be added to the existing pole 52 of the finished upper cover assembly by screw connection or welding to ensure that the pole 52 can extend out of the housing 1. The horizontal cross-section of the pole adapter 521 may be cylindrical or square.

[0081] If a self-made upper cover assembly is used, a through slot 522 can be directly opened on the pole 52;

[0082] If a finished upper cover assembly is used, a through slot 522 may be provided on the pole adapter 521 .

[0083] Example 2

[0084] This embodiment provides a single battery 2, the specific structure of which is as follows Figures 6 to 8 As shown, it includes an outer cylinder 6, an upper cover assembly 5, a lower cover assembly 7 and an electrode assembly;

[0085] The outer cylinder 6 is open at both the top and bottom. The upper cover assembly 5 and the lower cover assembly 7 are fixed to the upper and lower open ends of the outer cylinder 6 by welding, thereby forming a closed single cell cavity. The electrode assembly is installed in the cavity of the single cell, and the electrode assembly is connected to the pole in the upper cover assembly 5; the electrolyte is provided in the cavity of the single cell 2.

[0086] The upper cover assembly 5 in this embodiment adopts the same structure as that in the first embodiment.

[0087] like Figure 6 As shown, the gas port 52 may be the explosion relief portion 57 of the single cell, and the explosion relief portion may be an explosion relief membrane or an explosion relief valve. Figure 7As shown, the gas port 52 may also be a sealing mechanism 56, which is opened by the electrolyte or an external force to form a through hole. The form of the sealing mechanism 56 can be specifically referred to patent CN218525645U.

[0088] The structure of this single cell is similar to that of commercially available square lithium-ion batteries, except that a hollow component needs to be added to the upper cover assembly. There are two ways to actually manufacture the single cell of this embodiment:

[0089] Method 1: Improvements can be made to commercially available prismatic lithium-ion batteries by welding two hollow components directly to the upper cover assembly. Insulation between the terminal and the hollow components is then ensured by pouring insulating adhesive or installing insulating rubber sleeves. However, this method is labor-intensive and time-consuming, resulting in low efficiency.

[0090] Method 2: You can assemble the cells yourself. The top cover assembly of the cells will need to be remade. Specifically, two hollow components will need to be integrally formed on the top cover assembly. Insulation between the terminal and the hollow component will be ensured by pouring insulating glue or installing insulating rubber sleeves. In some cases, the gas port of the top cover assembly will need to be sealed. The other components of the cells can be consistent with commercially available prismatic lithium-ion batteries, and the assembly process is basically the same as for commercially available prismatic lithium-ion batteries.

[0091] Example 3

[0092] This embodiment provides a large capacity battery, such as Figure 8 and Figure 9 As shown, the large-capacity battery includes a shell 1, N single cells 2 with the same structure as in Example 2, where N is greater than or equal to 2; the N single cells 2 are arranged side by side and as a whole are arranged inside the shell 1; a shared chamber 4 is provided on the top of the shell 1; the portion of the hollow component 53 of the upper cover assembly 5 in the single cell 2 away from the cover body can be bent outward and sealed and welded to the surrounding area corresponding to a first through hole 3 on the shell 1; the pole of the single cell 2 extends out of the shell 1, and the pole and the hollow component 53 are kept insulated.

[0093] It should be noted that in this embodiment, in order to ensure the operability and reliability of welding between the shell of the large-capacity battery and the hollow component after welding, since the shells of the single cells are all made of aluminum, the hollow component and the shell of the large-capacity battery are also made of aluminum.

[0094] In this embodiment, the gas port on the single cell is a sealing mechanism, which can be opened under the action of electrolyte or external force, thereby allowing the gas area in the inner cavity of the single cell 2 to communicate with the shared chamber.

[0095] It should be emphasized that an exhaust valve can be set on the shared chamber to regularly discharge the gas in each single cell, thereby avoiding a series of problems that affect the comprehensive performance of large-capacity batteries, such as bulging of the single cell shell due to the inability to discharge gas. An exhaust valve and an explosion-proof membrane can also be set on the gas chamber 8, or only an exhaust valve can be set; the exhaust valve can be opened manually or automatically, and the exhaust valve can be opened regularly to regularly discharge the gas in each single cell, thereby avoiding a series of problems that affect the comprehensive performance of large-capacity batteries, such as bulging of the single cell shell due to the inability to discharge gas. When an exhaust valve and an explosion-proof membrane are set at the same time, the exhaust valve and the explosion-proof membrane are located at both ends of the gas chamber. The explosion-proof membrane is used to prevent the thermal runaway smoke from breaking through the explosion-proof membrane and discharging from the gas chamber 8 when thermal runaway occurs in any single cell, so that such large-capacity batteries have higher safety performance.

[0096] In order to reduce the problem of thermal runaway caused by excessively high local temperatures at the poles of each single cell in a large-capacity battery, in this embodiment, heat transfer tubes are mounted on poles with the same polarity on each single cell of the large-capacity battery.

[0097] The shell of a large-capacity battery can be constructed in the following three forms:

[0098] 1. See Figure 9 and Figure 10 The housing 1 includes a cylinder 11, a first cover plate 12, and a second cover plate 13; the top and bottom of the cylinder 11 are both open, the first cover plate 12 is sealed and fixed (welded) to the top of the cylinder 11, and the second cover plate 13 is sealed and fixed (welded) to the bottom of the cylinder 11;

[0099] A shared cavity and 2N first through holes 3 are integrally formed on the first cover plate 12 , and the 2N first through holes 3 are arranged on both sides of the shared cavity.

[0100] 2. See Figure 9 、 Figure 10 as well as Figure 11 The outer shell 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 shell 14 are all open, the first cover plate 12 is sealed and fixed (welded) to the top of the U-shaped shell 14, and the third cover plate 15 and the fourth cover plate 16 are sealed and fixed (welded) to the front and rear of the U-shaped shell 14 respectively.

[0101] A shared cavity and 2N first through holes 3 are integrally formed on the first cover plate 12 , and the 2N first through holes 3 are arranged on both sides of the shared cavity.

[0102] 3. See Figure 9The housing 1 includes a cylinder 11, a third cover plate 15, and a fourth cover plate 16; the front and rear of the cylinder 11 are open, the third cover plate 15 is sealed and fixed (welded) to the front of the cylinder 11, and the fourth cover plate 16 is sealed and fixed (welded) to the rear of the cylinder;

[0103] A shared cavity and 2N first through holes 3 are integrally formed on the top of the cylinder 11 , and the 2N first through holes 3 are arranged on both sides of the shared cavity.

[0104] In the above three types of shells, the cylinder 11 and the U-shaped shell 14 can be spliced ​​together by welding, or can be integrally formed by casting or stamping. In order to facilitate processing while ensuring sealing, this embodiment chooses the integral forming method.

[0105] Example 4

[0106] See also Figure 8 The large-capacity battery structure of this embodiment is basically the same as that of Example 3, with the difference being that the gas port of the single cell is the explosion vent, and the shared chamber covers the explosion vent. When thermal runaway occurs in the single cell, the thermal runaway smoke breaks through the explosion vent and can be discharged through the shared chamber.

[0107] Example 5

[0108] This embodiment provides a single battery 2, the specific structure of which is as follows Figure 6 、 Figure 7 as well as Figure 12 As shown, it includes an outer cylinder 6, an upper cover assembly 5, a lower cover assembly 7 and an electrode assembly;

[0109] The outer cylinder 6 is open at both the top and bottom. The upper cover assembly 5 and the lower cover assembly 7 are fixed to the upper and lower open ends of the outer cylinder 6 by welding, thereby forming a closed single cell cavity. The electrode assembly is installed in the cavity of the single cell, and the electrode assembly is connected to the pole in the upper cover assembly 5; the electrolyte is provided in the cavity of the single cell 2.

[0110] The upper cover assembly 5 in this embodiment adopts the same structure as that in the first embodiment.

[0111] In this embodiment, a sealing mechanism is provided on the lower cover assembly. The sealing mechanism 56 is opened by the action of electrolyte or external force to form a through hole. The form of the sealing mechanism 56 can be specifically referred to in patent CN218525645U.

[0112] The structure of this single cell is similar to that of commercially available square lithium-ion batteries. The difference is that a hollow component needs to be added to the upper cover assembly and a sealing mechanism needs to be added to the lower cover assembly. There are two ways to actually manufacture the single cell of this embodiment:

[0113] Method 1: Improvements can be made to commercially available prismatic lithium-ion batteries. This involves welding two hollow components directly to the upper cover assembly. Insulation between the terminal and the hollow components is then ensured by pouring insulating adhesive or installing insulating rubber sleeves. A hole is then drilled in the lower cover assembly, and a sealing mechanism is installed at the opening. However, this method is labor-intensive and time-consuming, resulting in low efficiency.

[0114] Method 2: You can assemble the single battery cells yourself. The upper cover assembly of the single battery cells needs to be remade, that is, two hollow components need to be integrally formed on the upper cover assembly, and insulation between the pole and the hollow component is ensured by pouring insulating glue or setting insulating rubber sleeves; the lower cover assembly also needs to be remade, that is, a sealing mechanism is set on the lower cover assembly; in some cases, the gas port of the upper cover assembly also needs to adopt a sealing mechanism.

[0115] The other components of the single cell battery can be consistent with the commercially available square lithium-ion batteries, and the assembly process of the single cell battery is basically the same as that of the commercially available square lithium-ion batteries.

[0116] Example 6

[0117] like Figure 13 As shown, the high-capacity battery structure of this embodiment is basically the same as that of Example 3, with only one shared chamber. The difference is that the single cells adopt the structure of Example 5; the shared chamber is located at the bottom of the housing and is used to connect the electrolyte areas of the individual cells. Because the individual cells share the electrolyte, multiple cells in this embodiment need to be arranged in parallel.

[0118] When the sealing mechanism 56 on the lower cover assembly of each single cell is opened under the action of electrolyte or external force, the electrolyte area of ​​each single cell is connected to the shared chamber, and then each single cell is placed in a common electrolyte system, thereby improving the performance and cycle life of large-capacity batteries.

[0119] The shell of a large-capacity battery can be constructed in the following three forms:

[0120] 1. See Figure 14 and Figure 16 As shown, the housing 1 includes a cylinder 11, a first cover plate 12, and a second cover plate 13; the top and bottom of the cylinder 11 are both open, the first cover plate 12 is sealed and fixed (welded) to the top of the cylinder 11, and the second cover plate 13 is sealed and fixed (welded) to the bottom of the cylinder 11;

[0121] 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 cavity.

[0122] 2. See Figure 14 and Figure 15The outer shell 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 shell 14 are all open, the first cover plate 12 is sealed and fixed (welded) to the top of the U-shaped shell 14, and the third cover plate 15 and the fourth cover plate 16 are sealed and fixed (welded) to the front and rear of the U-shaped shell 14 respectively.

[0123] The first cover plate 12 is provided with 2N first through holes 3 , and a shared cavity is integrally formed on the bottom of the U-shaped shell 14 .

[0124] 3. See Figure 14 The housing 1 includes a cylinder 11, a third cover plate 15, and a fourth cover plate 16; the front and rear of the cylinder 11 are open, the third cover plate 15 is sealed and fixed (welded) to the front of the cylinder 11, and the fourth cover plate 16 is sealed and fixed (welded) to the rear of the cylinder;

[0125] 2N first through holes 3 are provided on the top of the cylinder 11 , and a shared cavity is integrally formed at the bottom of the cylinder 11 .

[0126] In the above three types of housings, the cylinder 11 and the U-shaped shell 14 can be spliced ​​together by welding, or can be integrally formed by casting or stamping. In order to facilitate processing while ensuring sealing, the integral forming method is usually selected.

[0127] Example 7

[0128] like Figure 17 As shown, this embodiment is based on the embodiment 6 (electrolyte can be shared), and a shared chamber 4 is added on the top of the shell; that is, the large-capacity battery of this embodiment has two shared chambers 4.

[0129] When the gas port 54 in the upper cover assembly 5 of the single cell 2 is a sealing mechanism 56 , the sealing mechanism is opened under the action of electrolyte or external force, thereby allowing the gas area in the inner cavity of the single cell 2 to communicate with the additional shared chamber.

[0130] When the gas port 54 in the upper cover assembly 5 of the single cell 2 is an explosion vent, the shared chamber covers the explosion vent of each single cell 2 to ensure that the smoke from thermal runaway of the single cell breaks through the explosion vent and is discharged through the added shared chamber.

[0131] The shell of a large-capacity battery can be constructed in the following three forms:

[0132] 1. See Figure 18 The housing 1 includes a cylinder 11, a first cover plate 12, and a second cover plate 13; the top and bottom of the cylinder 11 are both open, the first cover plate 12 is sealed and fixed (welded) to the top of the cylinder 11, and the second cover plate 13 is sealed and fixed (welded) to the bottom of the cylinder 11;

[0133] See also Figure 10 , the first cover plate 12 is provided with 2N first through holes 3 and a shared cavity is integrally formed, see Figure 16 A shared cavity is also integrally formed on the second cover plate 13 .

[0134] 2. See Figure 18 The outer shell 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 shell 14 are all open, the first cover plate 12 is sealed and fixed (welded) to the top of the U-shaped shell 14, and the third cover plate 15 and the fourth cover plate 16 are sealed and fixed (welded) to the front and rear of the U-shaped shell 14 respectively.

[0135] See also Figure 10 , the first cover plate 12 is provided with 2N first through holes 3 and a shared cavity is integrally formed, see Figure 15 The bottom of the U-shaped shell 14 is also integrally formed with a shared chamber.

[0136] 3. See Figure 18 The housing 1 includes a cylinder 11, a third cover plate 15, and a fourth cover plate 16; the front and rear of the cylinder 11 are open, the third cover plate 14 is sealed and fixed (welded) to the front of the cylinder 11, and the fourth cover plate 16 is sealed and fixed (welded) to the rear of the cylinder;

[0137] The top of the cylinder 11 is provided with 2N first through holes 3 and a shared cavity is integrally formed therewith. The bottom of the cylinder 11 is also integrally formed therewith.

[0138] In the above three types of housings, the cylinder 11 and the U-shaped shell 14 can be spliced ​​together by welding, or can be integrally formed by casting or stamping. In order to facilitate processing while ensuring sealing, the integral forming method is usually selected.

Claims

1. A large-capacity battery, characterized in that: The device comprises a housing and a plurality of single cells; the multiple single cells are arranged side by side and integrally arranged inside the housing; a shared chamber is provided on the top of the housing; The single cell includes a barrel, an upper cover assembly, a lower cover assembly and an electrode assembly; The upper cover assembly includes a cover body, two hollow components arranged on the cover body, two poles and a gas port located between the two poles; Both ends of the hollow member are open; The two poles are insulated from the cover body and pass through their respective hollow components, and insulation is maintained between the poles and the hollow components; The portion of the hollow component on the single battery away from the cover body is sealed and welded to the area corresponding to the first through hole on the shell; the pole of the single battery extends out of the shell.

2. A large-capacity battery according to claim 1, characterized in that: The gas openings on the single cells are through holes, the shared chamber is integrally formed on the top of the housing, and the shared chamber is connected to the gas areas of each single cell through the through holes of each single cell.

3. A large-capacity battery according to claim 1, characterized in that: The gas outlet on the single cell is the explosion vent part, and the shared chamber is integrally formed on the top of the shell. The shared chamber covers the explosion vent part of each single cell to ensure that the smoke from thermal runaway of the single cell breaks through the explosion vent part and is discharged through the shared chamber.

4. A large-capacity battery according to any one of claims 1 to 3, characterized in that: A shared chamber is provided at the bottom of the shell for connecting the electrolyte areas of each single battery.

5. A large-capacity battery according to claim 1, characterized in that: A heat transfer tube is mounted on the poles of the same polarity on each single battery.

6. A large-capacity battery according to claim 1, characterized in that: The hollow component is integrally formed on the cover body.

7. A large-capacity battery according to claim 6, characterized in that: The side wall of the hollow component is provided with a buffer deformation groove.

8. A large-capacity battery according to claim 6, characterized in that: The outer surface of the pole is engraved with knurling.

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