End plate assembly, shell for high-capacity battery and high-capacity battery

Abstract

The utility model belongs to the field of batteries, and particularly relates to an end plate assembly, a shell for a high-capacity battery and the high-capacity battery. The technical problem that an existing high-capacity battery end plate assembly is complex in structure and assembly is solved. The end plate assembly comprises a first end plate, a second end plate and a first supporting rib which are integrally arranged; a first through hole is formed in the first end plate, and the first end plate is used for being matched with an explosion venting mechanism fixed at the first through hole to seal the open end of a gas chamber, the open end of an electrolyte sharing chamber and the open end of a cylinder of the high-capacity battery; the second end plate is parallel to the first end plate; the first supporting rib is fixed between the first end plate and the second end plate, and a gas channel is formed between the second end plate and the first end plate; the gas inlet end of the gas channel is communicated with a gas chamber of the high-capacity battery, and the gas outlet end is communicated with the first through hole; in the height direction of the first end plate, the gas inlet end of the gas channel is higher than the gas outlet end. The end plate assembly is simple in structure, convenient to machine and low in cost.

Description

Technical Field

[0001] The utility model belongs to the field of batteries, and in particular relates to an end plate assembly, a shell for a large-capacity battery, and a large-capacity battery. Background Art

[0002] Currently, many single cells are connected in parallel or in series on the market to form large-capacity batteries (also called battery modules or battery packs).

[0003] However, the individual cells in existing large-capacity batteries are different from each other. Due to the existence of the barrel effect, they are often affected by the cell with the worst performance, which greatly limits the capacity limit and cycle times of the entire large-capacity battery. Therefore, how to improve the uniformity of each cell in a large-capacity battery has become the focus and difficulty of research in this field.

[0004] In order to solve the above problems, CN220797038U discloses a large-capacity battery, such as Figure 1 The large-capacity battery includes a shell and a plurality of single cells; the plurality of single cells are placed in parallel in the shell, and a through hole is provided on the top plate 01 of the shell corresponding to the pole of each single cell for the pole of the single cell to extend out of the shell; each pole of the single cell extends out of the through hole and the shell area corresponding to the through hole is fixedly sealed with the shell of the single cell.

[0005] The bottom plate 02 of the housing is provided with an electrolyte sharing chamber ( Figure 1 The electrolyte sharing chamber is located inside the outer shell, and the position indicated by reference numeral 12 is a port of the electrolyte sharing chamber. The electrolyte sharing chamber is connected to the electrolyte area of ​​the inner cavity of each single cell. Through the electrolyte sharing chamber, each single cell can be placed in a unified electrolyte environment, thereby ensuring the uniformity of the electrolyte in each single cell and improving the performance and cycle life of large-capacity batteries.

[0006] The top plate 01 of the housing is provided with a gas chamber, which can be connected to the gas area of ​​the inner cavity of each single cell to achieve gas balance of each single cell, further improving the performance and cycle life of large-capacity batteries. The gas chamber can also be used as an explosion relief channel. When any single cell has thermal runaway, the thermal runaway smoke in the inner cavity of the single cell enters the gas chamber and breaks through the explosion relief mechanism set at either end of the gas chamber and is discharged.

[0007] In order to ensure that the electrolyte in the inner cavity of the shell is not affected by the external environment, the sealing of the shell is particularly important.

[0008] In the above patent, the outer shell is composed of a cylinder assembly (including a cylinder and a gas chamber and an electrolyte shared chamber) and an end plate assembly seal-welded at both ends thereof, a through hole is opened in the area opposite to the end plate assembly and the gas chamber, and the explosion relief mechanism is seal-welded to the end plate assembly area around the through hole.

[0009] In the above-mentioned large-capacity battery, since through holes need to be opened on the two side areas of the outer shell top plate 01, the size of the gas chamber arranged in the middle of the outer shell top plate 01 is limited in the y direction (the width direction of the cylinder), which leads to the area of ​​the end plate assembly facing the gas chamber being insufficient in the y direction, making it difficult to install the explosion relief mechanism.

[0010] In order to solve this problem, Chinese patent CN221041321 U discloses an end plate assembly, including a first end plate and a second end plate; the first end plate is provided with a first through hole, and the first end plate is used to cooperate with the explosion relief mechanism fixed at the first through hole to seal the gas chamber open end, the electrolyte shared chamber open end and the cylinder open end of the large-capacity battery; the second end plate is parallel to the first end plate and there is a gap between the two, and the gap serves as a second channel; the air inlet end of the second channel is used to communicate with the gas chamber of the large-capacity battery, and the air outlet end is connected to the first through hole. In this patent, the problem of the explosion relief mechanism being difficult to install is overcome by adjusting the fixing area of ​​the explosion relief mechanism from the area of ​​the end plate assembly directly facing the gas chamber open end to the electrolyte shared chamber open end with a larger area or the end plate assembly area between the gas chamber open end and the electrolyte shared chamber open end.

[0011] However, in this patent, the first end plate and the second end plate are connected by screws, and a plurality of gaskets 03 are provided to ensure a gap between the two, making the entire end plate assembly and assembly more complicated. Summary of the invention

[0012] The utility model aims to provide an end plate assembly, a shell for a large-capacity battery and a large-capacity battery, so as to overcome the technical problems of the existing large-capacity battery end plate assembly structure and complicated assembly.

[0013] The utility model provides an end plate assembly in a first aspect, which is special in that: it comprises a first end plate, a second end plate and a first supporting rib; the first end plate, the second end plate and the first supporting rib are an integral part, and can be integrally processed and formed by an aluminum extrusion process;

[0014] A first through hole is formed on the first end plate, and the first end plate is used to cooperate with the explosion relief mechanism fixed at the first through hole to seal the open end of the gas chamber, the open end of the electrolyte shared chamber and the open end of the cylinder of the large-capacity battery;

[0015] The second end plate is parallel to the first end plate;

[0016] The first supporting rib is fixed between the first end plate and the second end plate so as to form a gap between the second end plate and the first end plate as a gas passage;

[0017] The gas inlet end of the gas channel is used to communicate with the gas chamber of the large-capacity battery, and the gas outlet end is communicated with the first through hole; in the height direction of the first end plate, the gas inlet end of the gas channel is higher than the gas outlet end.

[0018] The utility model fixes a first supporting rib between the first end plate and the second end plate to form a gap between the second end plate and the first end plate as a gas passage; compared with the method of using screws and gaskets, the structure of the end plate assembly of the utility model is simpler, and is easy to process, with lower cost, and at the same time has higher structural stability.

[0019] Furthermore, the above-mentioned end plate assembly has two first support ribs, each of which extends along the height direction of the first end plate, and the two first support ribs are arranged along the width direction of the first end plate, and a gas channel is formed between the second end plate, the first end plate and the two first support ribs.

[0020] Furthermore, the end plate assembly further includes a third end plate that is closely attached to the inner surface of the second end plate. By adding the third end plate, on the one hand, by adjusting the size of the third end plate along the x direction (the arrangement direction of the single cells, which is also the length direction of the shell and the cylinder), all the single cells can be clamped in the x direction to improve the stability of each single cell in the inner cavity of the shell, and it can also prevent each single cell from swelling, which may lead to the problem of reduced cycle performance of large-capacity batteries; on the other hand, the third end plate can further reduce the impact of thermal runaway smoke in the gas channel on the outermost single cell.

[0021] Furthermore, a second through hole is provided on the first end plate, and the second through hole is arranged facing the large-capacity battery gas chamber.

[0022] Furthermore, the utility model designs different first end plates for cylinder assemblies of different structures (different cylinder assemblies have electrolyte sharing chambers of different structures);

[0023] For the cylinder assembly structure which is integrally formed with the bottom plate of the shell, or a pipe section is arranged outside the bottom plate of the shell to form a liquid channel as a shared chamber for the electrolyte, the corresponding first end plate structure is as follows:

[0024] The first end plate includes a first sub-end plate, a second sub-end plate and a third sub-end plate;

[0025] The first sub-end plate is used to seal the open end of the gas chamber of the large-capacity battery;

[0026] The second sub-end plate is used for the open end of the electrolyte sharing chamber of the large sealed capacity battery;

[0027] The third sub-end plate is located between the first sub-end plate and the second sub-end plate and is connected to the first sub-end plate and the second sub-end plate, and is used to seal the open end of the cylinder;

[0028] The first through hole is opened on at least a portion of the third sub-end plate and the second sub-end plate.

[0029] Furthermore, on the yz plane, the orthographic projection of the second end plate is located on the third sub-end plate, and the projection area is less than or equal to the area of ​​the third sub-end plate, so as to prevent the second end plate from blocking the first through hole.

[0030] For the cylinder assembly structure in which a support is provided between the lower cover plate of the single cell and the bottom plate of the cylinder to form a liquid channel as an electrolyte shared chamber, the corresponding first end plate structure is as follows:

[0031] The first end plate includes a first sub-end plate and a fourth sub-end plate;

[0032] The first sub-end plate is used to seal the open end of the gas chamber of the large-capacity battery;

[0033] The fourth sub-end plate is used to simultaneously seal the open end of the electrolyte sharing chamber of the large-capacity battery and the open end of the large-capacity battery cylinder;

[0034] The first through hole is opened in the fourth sub-end plate area.

[0035] The second aspect of the utility model also provides a large-capacity battery housing, which is special in that it includes a barrel assembly and at least one of the above-mentioned end plate assemblies;

[0036] The barrel assembly includes a barrel and a gas chamber and an electrolyte shared chamber;

[0037] The two opposite ends of the cylinder are open ends; the top plate of the cylinder is provided with avoidance holes corresponding to the polarity terminals of the single cells for the polarity terminals of the single cells to extend out;

[0038] The gas chamber is a gas passage arranged on the top plate of the cylinder and extending along the length direction of the cylinder;

[0039] The electrolyte sharing chamber is a liquid channel arranged on the bottom plate of the cylinder and extending along the length direction of the cylinder;

[0040] The end plate assembly is sealed at the open end of the cylinder, and simultaneously seals the open end of the gas chamber and the open end of the electrolyte shared chamber of the large-capacity battery.

[0041] The third aspect of the utility model also provides a large-capacity battery, which is special in that it includes a shell and a plurality of single cells arranged in the shell in the same direction;

[0042] The outer shell is the outer shell for the above-mentioned large-capacity battery;

[0043] The polarity terminals of each single battery extend out of the corresponding avoidance hole, and the top plate area of ​​the cylinder corresponding to the avoidance hole is fixedly sealed with the single battery shell;

[0044] The gas chamber covers the gas port of each single cell;

[0045] The inner cavity of the electrolyte sharing chamber is connected with the inner cavity of each single battery;

[0046] The explosion relief mechanism is fixed in the first end plate area around the first through hole to seal the first through hole.

[0047] Furthermore, a sealing sheet is fixed to the first end plate area around the second through hole to seal the second through hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a structural schematic diagram of a large-capacity battery in the background technology;

[0049] Figure 2 It is a schematic diagram of a partial structure explosion of another large-capacity battery in the background technology;

[0050] Figure 3 This is a schematic diagram of the structure of a cylinder assembly of a large-capacity battery in Example 1;

[0051] Figure 4 It is a partial structural schematic diagram of another cylinder assembly of a large-capacity battery in Example 1 (the cylinder bottom plate and the electrolyte share a chamber);

[0052] Figure 5 It is a partial structural schematic diagram of a cylinder assembly of a large-capacity battery in Example 1 (cylinder top plate and gas chamber);

[0053] Figure 6 This is a schematic structural diagram of the end plate assembly in Example 1 from a first viewing angle;

[0054] Figure 7 This is a schematic structural diagram of the end plate assembly in Example 1 from a second viewing angle;

[0055] Figure 8 This is a schematic structural diagram of the end plate assembly in Example 1 from a third viewing angle;

[0056] Fig. 9 This is a schematic structural diagram of the end plate assembly in Example 1 from a fourth viewing angle;

[0057] Fig.10 This is a schematic diagram of the structure of a large-capacity battery in Example 1;

[0058] Fig.11 Schematic diagram of the local explosion structure of a large-capacity battery in Example 1 Figure 1 ;

[0059] Fig.12 Schematic diagram of the local explosion structure of a large-capacity battery in Example 1 Figure 2 ;

[0060] Fig.13 It is a structural schematic diagram of the end plate assembly in Example 2;

[0061] Fig.14 This is a schematic diagram of the structure of a cylinder assembly of a large-capacity battery in Example 3;

[0062] Fig.15 This is a schematic structural diagram of another cylinder assembly of a large-capacity battery in Example 3;

[0063] Fig.16 This is a schematic diagram of the structure of the end plate assembly in Example 3;

[0064] Fig.17 This is a schematic diagram of the structure of a large-capacity battery in Example 3;

[0065] The accompanying drawings in the figure are marked as follows:

[0066] 01. Shell top plate; 02. Shell bottom plate; 03. Gasket;

[0067] 1. Cylinder assembly; 11. Cylinder; 111. Cylinder bottom plate; 112. Cylinder top plate; 12. Electrolyte shared chamber; 13. Gas chamber; 2. End plate assembly; 21. First end plate; 211. First sub-end plate; 212. Second sub-end plate; 213. Third sub-end plate; 22. Second end plate; 23. First supporting rib; 3. Explosion relief mechanism; 4. Sealing plate; 5. Avoidance hole; 6. Support block; 7. First hole; 8. Insulating support rod; 9. First through hole; 10. Second through hole; 15. Third end plate; 16. Second supporting rib; 17. Third supporting rib; 18. Fourth sub-end plate; 19. Gas channel. DETAILED DESCRIPTION

[0068] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the utility model, but not all of them. Based on the embodiments of the utility model, all other embodiments obtained by ordinary persons in the field without creative work should fall within the scope of protection of the utility model.

[0069] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0070] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "top, bottom" etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first, second, third, fourth, etc." are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0071] The utility model provides an end plate assembly suitable for a large-capacity battery. Such a large-capacity battery comprises an outer shell and a plurality of parallel-connected single cells arranged in the outer shell; the inner cavity of each single cell comprises an electrolyte region and a gas region.

[0072] The housing includes a barrel assembly and first and second end plate assemblies.

[0073] The cylinder assembly includes a cylinder and a gas chamber and an electrolyte shared chamber;

[0074] The two opposite ends of the cylinder are open ends, and the top plate of the cylinder is provided with avoidance holes corresponding to the polarity terminals of the single cells for the polarity terminals of the single cells to extend out;

[0075] The gas chamber is arranged on the top plate of the cylinder, extends along the length direction of the cylinder, and covers the gas openings on the tops of the individual cells in the large-capacity battery.

[0076] It should be noted that the gas port here includes the following two meanings:

[0077] 1) The gas port is a through hole directly opened on the upper cover plate of the single cell and penetrating the inner cavity of the single cell;

[0078] At this time, the inner cavity of the gas chamber is connected with the gas area of ​​the inner cavity of each single cell through the gas port. The gas chamber serves as a gas sharing chamber for each single cell. Based on the gas chamber, the gas areas of each single cell can be connected to achieve gas balance, so that the gas of each single cell is shared to ensure the consistency of each single cell, which improves the cycle life of the large-capacity battery to a certain extent; when any single cell has thermal runaway, the smoke in the inner cavity of the single cell enters the gas chamber and is discharged through the gas chamber, thereby improving the safety of the large-capacity battery.

[0079] 2) The gas port is an explosion vent or explosion-proof port provided on the upper cover plate of the single cell, and an explosion vent membrane is provided at the explosion vent or explosion-proof port;

[0080] At this time, the gas chamber is used as an explosion-proof passage. When the explosion-proof membrane at the gas port of any single battery is broken by the inner cavity smoke, the inner cavity smoke of the single battery is discharged through the gas chamber, thereby improving the safety of the large-capacity battery.

[0081] The electrolyte sharing chamber is arranged on the bottom plate of the cylinder, extends along the length direction of the cylinder, and is communicated with the electrolyte area of ​​the inner cavity of each single battery.

[0082] It should be noted here that:

[0083] 1. The electrolyte sharing chamber is an electrolyte containing chamber. After it is connected with the electrolyte area of ​​each single cell inner cavity, it is necessary to ensure that the electrolyte in the entire large-capacity battery does not contact the external environment. By sealing and covering the first end plate assembly and the second end plate assembly at the two opposite open ends of the cylinder (the open ends of the electrolyte sharing chamber and the gas chamber must be sealed at the same time), the electrolyte in the large-capacity battery can be prevented from contacting the external environment.

[0084] 2. At least one of the first end plate assembly and the second end plate assembly is the end plate assembly described in the present invention.

[0085] 3. The electrolyte sharing chamber described here is a liquid channel extending along the length direction of the shell and located between the bottom plate of the shell and each single cell. The liquid channel can be integrally formed with the bottom plate of the shell, or formed by arranging a pipe section outside the bottom plate of the shell, or by arranging a support between the lower cover plate of the single cell and the bottom plate of the cylinder.

[0086] The utility model comprises an end plate assembly including a first end plate and a second end plate, wherein a first through hole is provided on the first end plate, and the first end plate is used to cooperate with an explosion relief mechanism fixed at the first through hole to seal the open end of the gas chamber, the open end of the electrolyte shared chamber and the open end of the cylinder of the large-capacity battery; the second end plate is parallel to the first end plate; a first supporting rib is provided between the first end plate and the second end plate to form a gap therebetween as a gas passage; an air inlet end of the gas passage is used to communicate with the gas chamber of the large-capacity battery, and an air outlet end is communicated with the first through hole; in the height direction of the first end plate, the air inlet end of the gas passage is higher than the position of the air outlet end; when any single cell battery has thermal runaway, the smoke in the inner cavity of the single cell battery enters the gas chamber and the gas passage in turn, and is discharged by pushing open the explosion relief mechanism fixed at the first through hole of the first end plate.

[0087] For electrolyte sharing chambers of different structures, the structures of the corresponding end plate assemblies are slightly different, which are described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0088] For ease of description, in the following embodiments, the length direction of the cylinder is defined as the x direction, the width direction of the cylinder is defined as the y direction, and the height direction of the cylinder is defined as the z direction.

[0089] Example 1

[0090] The end plate assembly 2 of this embodiment is suitable for a large-capacity battery having the following electrolyte sharing chamber 12 structure:

[0091] The first structure, such as Figure 3 , which is a schematic diagram of the structure of a cylinder assembly 1 of such a large-capacity battery, a liquid channel extending along the x direction is formed on the cylinder bottom plate 111 as an electrolyte shared chamber 12. The cylinder bottom plate 111 is formed by convexly protruding in a direction away from the cylinder top plate 112, and can be formed directly on the cylinder bottom plate 111 by using an aluminum extrusion process.

[0092] The second structure, such as Figure 4 As shown, it is a schematic diagram of the partial structure of a cylinder assembly 1 of such a large-capacity battery; a tube segment extending along the x direction and having a square or circular cross-section is fixed on the outer surface of the cylinder bottom plate 111 (the inner cavity of the tube segment serves as the electrolyte shared chamber 12); through holes are opened in the tube wall and the cylinder bottom plate 111; the electrolyte shared chamber 12 is connected with the electrolyte area of ​​the inner cavity of each single battery through the through hole.

[0093] The two ends of the electrolyte shared chamber 12 in the above two structures located in the yz plane are open ends.

[0094] The gas chamber 13 of the large-capacity battery can adopt the following structural forms:

[0095] The first structure, such as Figure 3 As shown, a second channel extending along the x direction is provided on the cylinder top plate 112 ; the second channel can be directly formed on the cylinder top plate 112 by using an aluminum extrusion process, wherein the second channel protrudes in a direction away from the cylinder bottom plate 111 .

[0096] The second structure, such as Figure 5 As shown, a pipe section with a square or circular cross-section is fixed on the outer surface of the cylinder top plate 112 (the inner cavity of the pipe section serves as the gas chamber 13); through holes are opened in the pipe wall and the cylinder top plate 112.

[0097] The two ends of the gas chamber 13 in the above two structures located on the yz plane are open ends.

[0098] like Figures 6 to 9 The figure is a schematic diagram of the structure of the end plate assembly 2 of this embodiment, which includes a first end plate 21 and a second end plate 22 which are parallel to each other, and a first support rib 23 is arranged between the first end plate 21 and the second end plate 22 to form a gas channel 19. It can be seen from the figure that this embodiment includes two first support ribs 23, which extend along the z direction and are arranged in the y direction, and a gas channel 19 is formed between the first end plate 21, the second end plate 22 and the two first support ribs 23. In the z direction, the size of the two first support ribs 23 is the same as that of the second end plate 22, and the gas channel 19 extends along the z direction, with the upper end port serving as the gas inlet end of the gas channel 19 and the lower end port serving as the gas outlet end of the gas channel 19, which is connected to the first through hole 9 provided on the first end plate 21.

[0099] In some other embodiments, one or more first supporting ribs 23 may be provided between the first end plate 21 and the second end plate 22 , as long as a structurally stable gap is formed between the first end plate 21 and the second end plate 22 as the gas channel 19 .

[0100] When one first supporting rib 23 is used, the first supporting rib 23 may extend along the z direction and, in the y direction, may be located in the middle of the end plate 21 and the second end plate 22. However, compared with this embodiment, its structural stability is relatively weak.

[0101] When more than two first support ribs 23 are used, the first support ribs 23 can extend along the z direction and be arranged at equal intervals in the y direction. Compared with the present embodiment, the first support ribs 23 have higher structural strength, but the processing cost is higher.

[0102] In this embodiment, the end plate assembly 2 is an integral part, that is, the first end plate 21, the second end plate 22 and the first supporting rib 23 are an integral part, which can be integrally processed and formed by aluminum extrusion technology. Compared with separate parts, it has a stable structure and a lower processing cost.

[0103] In order to ensure that all the smoke caused by thermal runaway enters the gas channel 19, in the y direction, the distance between the two first support ribs 23 is preferably larger than the size of the gas chamber 13, that is, the size of the air inlet end of the gas channel 19 is larger than the size of the air outlet end of the gas chamber 13; when any single cell experiences thermal runaway, the smoke in the inner cavity of the single cell enters the gas chamber, and after being ejected from the gas chamber, all of the smoke can enter the gas channel 19, push open the explosion relief mechanism fixed at the first through hole of the first end plate and be discharged.

[0104] The end plate assembly 2 of this embodiment is used to be fixed on one of the open ends of the above-mentioned cylinder assembly 1, and cooperates with the explosion relief mechanism 3 fixed at the first through hole 9 to seal the open end of the cylinder 11 while sealing the open ends of the gas chamber 13 and the electrolyte shared chamber 12.

[0105] For the convenience of description, the first end plate 21 is divided into three areas according to different sealing objects, and the three areas are defined as a first sub-end plate 211, a second sub-end plate 212 and a third sub-end plate 213, as shown in FIG. Figure 8 shown.

[0106] The first sub-end plate 211 is used to seal the open end of the gas chamber 13 of the large-capacity battery. The shape of the first sub-end plate 211 is adapted to the shape of the open end of the gas chamber 13. The area of ​​the first sub-end plate 211 can be slightly larger than the area of ​​the open end of the gas chamber 13, and it is fixed to the open end of the gas chamber 13 by fusion welding; the area of ​​the first sub-end plate 211 can also be slightly smaller than the area of ​​the open end of the gas chamber 13, and it is fixed to the open end of the gas chamber 13 by embedding welding.

[0107] The second sub-end plate 212 is used to seal the open end of the electrolyte sharing chamber 12 of the large-capacity battery. The shape of the second sub-end plate 212 is compatible with the shape of the open end of the electrolyte sharing chamber 12. The area of ​​the second sub-end plate 212 can be slightly larger than the area of ​​the open end of the electrolyte sharing chamber 12, and it is fixed to the open end of the electrolyte sharing chamber 12 by fusion welding; the area can also be slightly smaller than the area of ​​the open end of the electrolyte sharing chamber 12, and it is fixed to the open end of the electrolyte sharing chamber 12 by embedding welding.

[0108] The third sub-end plate 213 is used to seal the open end of the cylinder 11 of the large-capacity battery. The shape of the third sub-end plate 213 is adapted to the shape of the open end of the cylinder 11. The area of ​​the third sub-end plate 213 can be slightly larger than the area of ​​the open end of the cylinder 11, and it is fixed to the open end of the cylinder 11 by fusion welding; the area of ​​the third sub-end plate 213 can also be slightly smaller than the area of ​​the open end of the cylinder 11, and it is fixed to the open end of the cylinder 11 by embedding welding.

[0109] It should be noted that, in this embodiment, the first sub-end plate 211, the second sub-end plate 212 and the third sub-end plate 213 are an integral part. In some other embodiments, a split structure can also be adopted. However, compared with the integral structure, firstly, its processing procedure is more complicated. Secondly, because the sub-end plates need to be connected to each other, each connection part is a weak part or a leak-prone point, which leads to weak sealing of the entire outer shell.

[0110] A first through hole 9 is provided in the first end plate 21 area corresponding to the second sub-end plate 212 or the open end of the electrolyte sharing chamber 12. Figure 8 It can be seen that in this embodiment, part of the first through hole 9 is located on the second sub-end plate 212, and the other part is located on the third sub-end plate 213. The explosion relief mechanism 3 is welded at the first through hole 9 (see Fig.10 );

[0111] Combination Fig. 9 It can be seen that the shape of the second end plate 22 of this embodiment is compatible with the shape of the third sub-end plate 213. On the yz plane, the positive projection of the second end plate 22 is located on the third sub-end plate 213, and the projection area is less than or equal to the third sub-end plate 213, avoiding the second end plate 22 from blocking the first through hole 9.

[0112] In some other embodiments, when the second end plate 22 is larger in size along the z direction, fixing it to the third sub-end plate 213 may block the first through hole 9, resulting in the gas channel 19 or the electrolyte shared chamber 12 being unable to communicate with the explosion relief mechanism 3. In order to solve this problem, a through hole or a notch that passes through the first through hole 9 can be opened in the second end plate 22 to ensure that the first through hole 9 is connected to the electrolyte shared chamber 12 or the gas channel 19.

[0113] like Figures 10 to 12, is a schematic diagram of the structure of a large-capacity battery in this embodiment. It can be seen from the figure that the large-capacity battery in this embodiment includes a shell and single cells arranged in the shell.

[0114] The outer shell is composed of the above-mentioned cylinder assembly 1 ( Figure 3 and Figure 4 The barrel assembly 1 shown in the figure and the first end plate assembly and the second end plate assembly covering the left and right open ends of the barrel assembly 1 are composed of; wherein the first end plate assembly adopts the above-mentioned end plate assembly 2 in this embodiment, and the structural form of the second end plate assembly can be similar to the first end plate assembly, except that the second end plate assembly does not have the first through hole 9. In some other embodiments, the second end plate assembly can be a flat plate that matches the shape of the open end of the barrel assembly 1.

[0115] The single cells in this embodiment are square-shell cells, and the number is 13. In other embodiments, the number and shape of the single cells can be adjusted according to actual needs. The inner cavity of each single cell includes an electrolyte area and a gas area.

[0116] Each single battery is arranged in the inner cavity of the cylinder assembly 1 along the x direction, and each single battery polarity terminal extends out of the corresponding avoidance hole 5 as a large-capacity battery polarity terminal. The cylinder top plate 112 area corresponding to the avoidance hole 5 is fixedly sealed with the single battery shell.

[0117] The single cell polarity terminal described here can be a single cell pole. If, in order to avoid the single cell pole being unable to smoothly extend out of the avoidance hole 5 as a polarity terminal or the height of the single cell pole extending out of the avoidance hole 5 does not meet the set requirements, a pole adapter can also be connected to the single cell pole, and the overall structure of the single cell pole and the pole adapter can be used as the single cell polarity terminal.

[0118] The gas chamber 13 covers the gas port at the top of each single cell in the large-capacity battery; the electrolyte sharing chamber 12 is connected to the electrolyte area of ​​the inner cavity of each single cell.

[0119] As can be seen from the figure, Figures 10 to 12 The barrel assembly 1 shown is Figure 3 Slightly different, Figures 10 to 12 The barrel assembly 1 shown in Figure 3 On the basis of the barrel assembly 1 shown, support blocks are respectively provided in the outer areas of the barrel bottom plate 111 on both sides of the electrolyte sharing chamber 12, and the support blocks extend along the x direction (the support block 6 and the barrel assembly 1 can be an integral part). As can be seen from the figure, a first hole 7 is provided on the support block along the x direction. Figure 3 The barrel assembly 1 shown, Figures 10 to 12The bottom of the barrel 11 of the barrel assembly 1 shown has a larger dimension in the y direction, so it has better stability when placed. At the same time, an insulating support rod 8 with a length greater than the barrel 11 and a cross-section that matches the cross-section of the first hole 7 can be inserted into the first hole 7 of the support block, and ensure that both ends of the insulating support rod 8 extend out of the end surface of the barrel 11. When a large-capacity battery with such a barrel assembly 1 is assembled into an energy storage device, the two ends of the insulating support rod 8 can be used as a support part and fixed to the support frame of the energy storage box, which is simple and convenient to operate, and can also improve the stability of such a large-capacity battery in the energy storage box.

[0120] The end plate assembly 2 is fixed to the open end of the cylinder assembly 1, and cooperates with the explosion relief mechanism 3 to seal the open end of the cylinder 11 while sealing the open ends of the gas chamber 13 and the electrolyte shared chamber 12. The gas chamber 13 and the electrolyte shared chamber 12 are connected through the gas channel 19 on the end plate assembly 2. When any single cell has thermal runaway, the smoke in its cavity rushes out from the gas port, and will pass through the gas chamber 13 and the gas channel 19 in turn, break open the explosion relief mechanism 3 and be discharged from the explosion relief mechanism 3. A hollow component with an explosion relief membrane at one end can be used as the explosion relief mechanism 3.

[0121] When the gas chamber 13 is used as an explosion relief channel, the first through hole 9 is located in the first end plate 21 area opposite to the open end of the electrolyte shared chamber 12. The first through hole 9 also serves as an operating port of the unpacking device. The unpacking device extends into the electrolyte shared chamber 12 through the first through hole 9 to unpack each single battery, so that the electrolyte shared chamber 12 and the electrolyte area of ​​the inner cavity of each single battery are connected (specifically, when unpacking, the unpacking device extends into the electrolyte shared chamber 12 through the first through hole 9 to open the sealing film sealed at the opening of the lower cover plate of each single battery. The specific sealing film can be the sealing film disclosed in Chinese patents CN218525645U and CN218525614U). In addition, the first through hole 9 can also be used as a liquid injection port. After the electrolyte area of ​​the inner cavity of each single battery is connected to the electrolyte shared chamber 12, the electrolyte can be injected into the inner cavity of each single battery and the electrolyte shared chamber 12 again through the first through hole 9 to ensure the continuity of the electrolyte. After the injection is completed, the explosion relief mechanism 3 is sealed and welded to the second sub-end plate 212 and the third sub-end plate 213 around the first through hole 9. Compared with the first through hole 9, the operation port or the injection port of the package opening device respectively provided in the end plate assembly 2, the overall structural strength of the end plate assembly 2 is higher, the structure is simple, and it is easy to process.

[0122] A second through hole 10 can also be opened in the first end plate 21 area corresponding to the open end of the gas chamber 13. After liquid is injected through the second through hole 10, the continuity of the electrolyte in the electrolyte sharing chamber 12 and the inner cavity of each single cell can be ensured. After the injection is completed, the sealing sheet 4 is sealed in the first sub-end plate 211 and the partial area of ​​the third sub-end plate 213 around the second through hole 10.

[0123] When the gas chamber 13 is used as a gas sharing chamber, in this embodiment, a second through hole 10 can be opened in the first end plate 21 area corresponding to the open end of the gas chamber 13. Fig.12 It can be seen that in this embodiment, the second through hole 10 is located on a part of the first sub-end plate 211 and the third sub-end plate 213, and the second through hole 10 is used as a liquid injection port. Electrolyte can be injected into the gas chamber 13 through the second through hole 10 to dissolve the sealing film sealed at the top opening of each single battery (the sealing film disclosed in Chinese patents CN218525645U and CN218525614U can be used. When injecting liquid, the entire large-capacity battery can be inverted to allow the sealing film to fully dissolve), so that the gas chamber 13 and the inner cavity of each single battery are connected; at the same time, after the large-capacity battery is placed upright, after injecting liquid through the second through hole 10, the continuity of the electrolyte in the electrolyte sharing chamber 12 and the inner cavity of each single battery can be ensured. After the injection is completed, the sealing sheet 4 is sealed in the first sub-end plate 211 and the third sub-end plate 213 around the second through hole 10.

[0124] Example 2

[0125] like Fig.13 As shown, the present embodiment can also add a third end plate 15 on the basis of embodiment 1, and the third end plate 15 is closely attached to the inner surface of the second end plate 22 (the surface of the second end plate 22 close to the single cell is defined as the inner surface). By adjusting the size of the third end plate 15 along the x direction, all single cells are clamped in the x direction, the stability of each single cell in the inner cavity of the shell is improved, and the problem of reducing the cycle performance of the large-capacity battery due to the swelling of each single cell can be prevented. In addition, the use of the third end plate 15 can further avoid the influence of the thermal runaway smoke on the outermost single cell.

[0126] It should be noted that after adding the third end plate 15, it is still necessary to ensure the connectivity of the gas chamber 13, the gas channel 19, the electrolyte shared chamber 12 and the explosion relief mechanism 3. This can be achieved by reducing the size of the third end plate 15 in the z direction so that it does not block the first through hole 9, or by opening a through hole or a gap in the corresponding part of the third end plate 15 and the first through hole 9.

[0127] Example 3

[0128] Different from Embodiment 1 and Embodiment 2, the end plate assembly 2 of this embodiment is suitable for a large-capacity battery having the following electrolyte sharing chamber 12 structure:

[0129] like Fig.14 , which is a schematic diagram of the structure of a cylinder assembly 1 of such a large-capacity battery, at least two second support ribs 16 extending along the x direction are provided on the inner surface of the cylinder bottom plate 111, and the two second support ribs 16 and the cylinder bottom plate 111 area located between the two second support ribs 16 constitute an electrolyte shared chamber 12. The two ends of the electrolyte shared chamber 12 located in the yz plane are open ends.

[0130] like Fig.15 As shown, it is a schematic diagram of the structure of another cylinder assembly 1 of such a large-capacity battery. A support member is provided on the cylinder bottom plate 111. The main part of the support member is a flat plate. The shape and size of the flat plate are adapted to the shape and size of the cylinder bottom plate 111. A third support rib 17 extending along the x direction is provided on the upper surface of the flat plate. There are three third support ribs 17, each of which extends along the x direction. The three third support ribs 17 are evenly arranged along the y direction. An electrolyte sharing chamber 12 is formed between two third support ribs 17. In order to improve the electrolyte sharing effect, a notch is provided on the third support rib 17 located in the middle to ensure that the liquid channels (electrolyte sharing chambers 12) located on both sides thereof are connected to each other.

[0131] The structure of the gas chamber 13 may be the same as that of the first embodiment, and will not be described in detail here.

[0132] like Fig.16 As shown, it is a schematic diagram of the structure of the end plate assembly 2 of this embodiment. Different from the end plate assembly 2 in Embodiment 1, the first end plate 21 of this embodiment is divided into two areas, which are respectively defined as the first sub-end plate 211 and the fourth sub-end plate 18.

[0133] The first sub-end plate 211 is used to seal the open end of the gas chamber 13 of the large-capacity battery. The shape of the first sub-end plate 211 is adapted to the shape of the open end of the gas chamber 13. The area of ​​the first sub-end plate 211 can be slightly larger than the area of ​​the open end of the gas chamber 13, and it is fixed to the open end of the gas chamber 13 by fusion welding; the area of ​​the first sub-end plate 211 can also be slightly smaller than the area of ​​the open end of the gas chamber 13, and it is fixed to the open end of the gas chamber 13 by embedding welding.

[0134] The fourth sub-end plate 18 is used to simultaneously seal the open end of the large-capacity battery cylinder 11 and the open end of the electrolyte shared chamber 12; because the electrolyte shared chamber 12 in this embodiment is located in the cylinder 11, when the fourth sub-end plate 18 is sealed and fixed to the open end of the cylinder 11 of the large-capacity battery, the open end of the electrolyte shared chamber 12 can be sealed at the same time. The shape of the fourth sub-end plate 18 is adapted to the shape of the open end of the cylinder 11, and the area can be slightly larger than the area of ​​the open end of the cylinder 11, and it is fixed to the open end of the cylinder 11 by fusion welding; the area can also be slightly smaller than the area of ​​the open end of the cylinder 11, and it is fixed to the open end of the cylinder 11 by embedding welding.

[0135] It should be noted that, in the present embodiment, the first sub-end plate 211 and the fourth sub-end plate 18 are an integral part. In some other embodiments, a split structure may be adopted. However, compared with the integral structure, firstly, its processing procedure is more complicated. Secondly, since each sub-end plate assembly 2 needs to be connected to each other, each connection part is a weak part or a leak-prone point, which leads to weak sealing of the entire outer shell.

[0136] In this embodiment, a first through hole 9 is provided in the fourth sub-end plate 18, and the first through hole 9 is preferably located in the region of the fourth sub-end plate 18 corresponding to the open end of the electrolyte sharing chamber 12, and the explosion relief mechanism 3 is welded to a part of the region of the fourth sub-end plate 18 around the first through hole 9; when any single cell has thermal runaway, the smoke in its inner cavity rushes out from the gas port, and will pass through the gas chamber 13 and the gas channel 19 in sequence, and break through the explosion relief mechanism 3 and be discharged from the explosion relief mechanism 3. The structure of the gas channel 19 is similar to that of Embodiments 1 and 2, except that in the z direction, the size of the second end plate 22 needs to be smaller than that of the fourth sub-end plate 18 to prevent the second end plate 22 from blocking the first through hole 9.

[0137] When the gas chamber 13 is used as an explosion relief channel, the first through hole 9 can also be used as an operating port of the package opening device and a liquid injection port. When the gas chamber 13 is used as a gas sharing chamber, a second through hole 10 can also be opened in the first end plate 21 area corresponding to the open end of the gas chamber 13. The specific content has been detailed in Example 1 and will not be repeated here.

[0138] like Fig.17 As shown, it is a schematic diagram of the structure of the large-capacity battery of this embodiment, including a shell and a plurality of single cells arranged in the shell along the length direction of the shell, wherein the shell includes the above-mentioned barrel assembly 1 ( Fig.14 and Fig.15The barrel assembly 1 is shown, and the first end plate assembly and the second end plate assembly are respectively sealed and fixed to the two opposite open ends of the barrel assembly 1, wherein at least one end plate assembly 2 is the end plate assembly 2 described in this embodiment. The polarity terminals of each single cell extend out of the corresponding avoidance hole 5 as the polarity terminals of the large-capacity battery, and the area of ​​the barrel top plate 112 corresponding to the avoidance hole 5 is fixedly sealed with the shell of the single cell. The gas chamber 13 covers the gas port on the top of each single cell in the large-capacity battery; the electrolyte shared chamber 12 is connected to the electrolyte area of ​​the inner cavity of each single cell.

[0139] The explosion relief mechanism 3 is fixed to the first end plate 21 area around the first through hole 9 to seal the first through hole 9; the sealing sheet 4 is fixed to the first end plate 21 area around the second through hole 10 to seal the second through hole 10. The other end plate assembly 2 can adopt a flat plate structure, which seals the open end of the cylinder 11 while sealing the open end of the gas chamber 13 and the open end of the electrolyte shared chamber 12.

Claims

1. An end plate assembly, characterized in that: It includes a first end plate, a second end plate and at least one first supporting rib; the first end plate, the second end plate and the first supporting rib are an integral part; A first through hole is formed on the first end plate, and the first end plate is used to cooperate with the explosion relief mechanism fixed at the first through hole to seal the open end of the gas chamber, the open end of the electrolyte shared chamber and the open end of the cylinder of the large-capacity battery; The second end plate is parallel to the first end plate; The first supporting rib is fixed between the first end plate and the second end plate, and a gas channel is formed between the second end plate and the first end plate; The gas inlet end of the gas channel is used to communicate with the gas chamber of the large-capacity battery, and the gas outlet end is communicated with the first through hole; in the height direction of the second end plate, the gas inlet end of the gas channel is higher than the gas outlet end.

2. The end plate assembly according to claim 1, characterized in that: It includes two first support ribs, each of which extends along the height direction of the second end plate, and the two first support ribs are arranged along the width direction of the first end plate. A gas channel is formed between the second end plate, the first end plate and the two first support ribs.

3. The end plate assembly according to claim 1, characterized in that: It also includes a third end plate which is closely attached to the inner surface of the second end plate.

4. The end plate assembly according to claim 1, characterized in that: The first end plate is also provided with a second through hole, and the second through hole is arranged facing the large-capacity battery gas chamber.

5. The end plate assembly according to any one of claims 1 to 4, characterized in that: The first end plate includes a first sub-end plate, a second sub-end plate and a third sub-end plate; The first sub-end plate is used to seal the open end of the gas chamber of the large-capacity battery; The second sub-end plate is used for the open end of the electrolyte sharing chamber of the large sealed capacity battery; The third sub-end plate is located between the first sub-end plate and the second sub-end plate and is connected to the first sub-end plate and the second sub-end plate, and is used to seal the open end of the cylinder; The first through hole is opened on at least a portion of the third sub-end plate and the second sub-end plate.

6. The end plate assembly according to claim 5, characterized in that: On the yz plane, the orthographic projection of the second end plate is located on the third sub-end plate, and the projection area is less than or equal to the area of ​​the third sub-end plate.

7. The end plate assembly according to claim 1, characterized in that: The first end plate includes a first sub-end plate and a fourth sub-end plate; The first sub-end plate is used to seal the open end of the gas chamber of the large-capacity battery; The fourth sub-end plate is used to simultaneously seal the open end of the electrolyte sharing chamber of the large-capacity battery and the open end of the large-capacity battery cylinder; The first through hole is opened in the fourth sub-end plate area.

8. A casing for a large-capacity battery, characterized in that: comprising a barrel assembly and at least one end plate assembly according to any one of claims 1 to 7; The barrel assembly includes a barrel and a gas chamber and an electrolyte shared chamber; The two opposite ends of the cylinder are open ends; the top plate of the cylinder is provided with avoidance holes corresponding to the polarity terminals of the single cells for the polarity terminals of the single cells to extend out; The gas chamber is a gas passage arranged on the top plate of the cylinder and extending along the length direction of the cylinder; The electrolyte sharing chamber is a liquid channel arranged on the bottom plate of the cylinder and extending along the length direction of the cylinder; The end plate assembly is sealed at the open end of the cylinder, and simultaneously seals the open end of the gas chamber and the open end of the electrolyte shared chamber of the large-capacity battery.

9. A large capacity battery, characterized in that: It comprises a housing and a plurality of single cells arranged in the housing in the same direction; The outer shell is the outer shell for a large-capacity battery as claimed in claim 8; The polarity terminals of each single battery extend out of the corresponding avoidance hole, and the top plate area of ​​the cylinder corresponding to the avoidance hole is fixedly sealed with the single battery shell; The gas chamber covers the gas port of each single cell; The inner cavity of the electrolyte sharing chamber is connected with the inner cavity of each single battery; The explosion relief mechanism is fixed in the first end plate area around the first through hole to seal the first through hole.

10. The large-capacity battery according to claim 9, characterized in that: A sealing sheet is fixed to the first end plate area around the second through hole to seal the second through hole.

Images