Battery cell structure and battery module
By opening welding holes on the cover, the pole ear is directly connected to the pole base, which solves the problem of difficult operation and high cost after the capacity of the single battery cell is increased, and realizes efficient production and low-cost battery cell structure.
Patent Information
- Application Number
- CN202422516062.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-17
- Publication Date
- 2025-09-30
- Estimated Expiration
- 2034-10-17
AI Technical Summary
In the prior art, the increase in the capacity of a single cell leads to an increase in the number of electrode layers, which makes the equipment for the folding and joining process difficult to operate, resulting in low production efficiency, low yield and high cost.
The cover plate is used to open the welding hole, and the pole ear is connected to the pole base through the welding hole, eliminating the folding and core closing process, and the pole ear is directly fixed to the pole base.
It improves production efficiency, reduces equipment development costs, and enhances the safety of the battery cell structure and connection reliability.
Smart Images
Figure CN223401844U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, and in particular to a battery core structure and a battery module. Background Art
[0002] As a new type of clean and renewable secondary energy, lithium-ion batteries have the advantages of high energy density, low self-discharge, good safety and rate performance. They have been widely used in various fields of life and production such as consumer electronics, electric vehicles, aerospace, medical equipment, energy storage, etc.
[0003] As the capacity of single-cell batteries continues to increase, the number of battery pole sheets is generally over 100. Typically, two pole groups are stacked separately, then the two poles are combined into a core using a connecting piece. Finally, the other end of the connecting piece is laser welded to the pole base to achieve electrical connection. However, when combining two poles into a core, due to the length of the battery cell (the combined length of the two pole groups is over 1 meter), the folding and joining process is difficult to operate, resulting in extremely low production efficiency and yield, and high equipment development costs. Utility Model Content
[0004] The purpose of the utility model is to provide a battery core structure and a battery module, which can save the process of folding and closing the core, improve efficiency and reduce cost.
[0005] To achieve this purpose, the present invention adopts the following technical solutions:
[0006] A battery cell structure, comprising:
[0007] A cover plate, wherein the cover plate is provided with a welding hole;
[0008] A pole assembly, comprising a pole body and a pole base, wherein the pole body is passed through the cover plate, the pole base is electrically connected to the pole body, and along the thickness direction of the cover plate, the pole base partially blocks the welding hole;
[0009] The pole group structure includes two pole group components, each of which includes a pole lug and a pole group body. The pole lugs of the same pole of the two pole group components constitute a pole lug group. The two pole lugs of the pole lug group pass through the welding hole and are fixedly connected to the side of the pole base facing away from the pole group body.
[0010] As an optional solution to the above-mentioned battery cell structure, the pole base is arranged on the side of the cover plate facing the pole group body, and the two pole tabs of the pole tab group pass through the welding hole through the gap between the pole base and the welding hole.
[0011] As an optional solution to the above-mentioned battery cell structure, the cover plate further includes a sealing plate, which is arranged in the welding hole to cover the pole base.
[0012] As an optional solution to the above-mentioned battery core structure, the cover plate is provided with a fixing groove, the sealing plate is arranged in the fixing groove and fixedly connected to the cover plate, and the welding hole is provided on the bottom surface of the fixing groove.
[0013] As an optional solution to the above-mentioned battery cell structure, along the stacking direction of the two electrode group components, the two electrode tabs of the electrode tab group are arranged at intervals, and the two electrode tabs of the electrode tab group pass through the welding hole from opposite sides of the electrode base.
[0014] As an optional solution to the above-mentioned battery cell structure, a retaining rib is provided on the side of the pole base facing away from the pole group body, and the two pole tabs of the pole tab group are respectively connected to the areas of the pole base located on both sides of the retaining rib.
[0015] As an optional solution to the above-mentioned battery core structure, the electrode group structure further includes an insulating film, and the insulating film is coated outside the two groups of the electrode group components.
[0016] As an optional solution to the above-mentioned battery cell structure, the battery cell structure includes two groups of pole assemblies, the pole group structure includes two groups of tab groups, the cover plate has two welding holes, and the two groups of pole assemblies, the two welding holes and the two groups of tab groups are arranged in a one-to-one correspondence.
[0017] As an optional solution to the above-mentioned battery cell structure, the battery cell structure includes a shell and an end plate, the pole group structure is arranged in the shell, the cover plate and the end plate are respectively arranged on opposite sides of the shell, and an explosion-proof valve is provided on the end plate.
[0018] A battery module comprises the battery cell structure, wherein a plurality of the battery cell structures are connected in series or in parallel.
[0019] Beneficial effects of the utility model:
[0020] The utility model provides a battery cell structure and battery module. In this battery cell structure, two sets of electrode group assemblies can be stacked, and then the same-pole tabs of the two sets of electrode group assemblies are passed through the welding holes and fixed to the side of the electrode base facing away from the electrode group body. This not only eliminates the process of folding the core, but also reduces the difficulty of fixing the tabs to the electrode base, thereby improving efficiency and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is an exploded view of the battery cell structure provided by the present utility model;
[0022] Figure 2 yes Figure 1 A partial enlarged view of point A in the middle;
[0023] Figure 3This is a structural diagram of the cover plate and pole assembly provided by the utility model;
[0024] Figure 4 It is a structural schematic diagram of the end plate provided by the utility model.
[0025] In the picture:
[0026] 1. Shell;
[0027] 2. Cover plate; 21. Welding hole; 22. Sealing plate; 23. Fixing groove; 24. Liquid injection hole;
[0028] 3. Pole assembly; 31. Pole body; 32. Pole base; 33. Rebar;
[0029] 4. Pole group structure; 41. Pole group assembly; 411. Pole lug; 412. Pole group body;
[0030] 5. End plate; 51. Explosion-proof valve. DETAILED DESCRIPTION
[0031] The following describes in detail embodiments of the present invention. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention.
[0032] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and 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 this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.
[0033] Unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," and "fixed" should be interpreted broadly. For example, they may refer to fixed or removable connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on specific circumstances.
[0034] Unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first feature being in direct contact with the second feature, or may include the first feature being in contact with the second feature through another feature between them instead of being in direct contact. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.
[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings and through specific implementation methods.
[0036] As a new type of clean and renewable secondary energy, lithium-ion batteries have the advantages of high energy density, low self-discharge, good safety and rate performance. They have been widely used in various fields of life and production such as consumer electronics, electric vehicles, aerospace, medical equipment, energy storage, etc.
[0037] This embodiment provides a battery module, including multiple battery cell structures, and according to the parameters required by the battery module, such as output voltage and capacity, the multiple battery cell structures are electrically connected in parallel or in series. Figure 1 As shown, the battery cell structure includes a shell 1, a cover plate 2 and a pole group structure 4. The pole group structure 4 is arranged in the shell 1. The cover plate 2 is fixedly connected to the shell 1 to provide a closed space with a certain structural strength for the pole group structure 4. The shell 1 is filled with electrolyte, and the cover plate 2 is provided with a pole assembly 3 connected to the pole group structure 4, so as to draw out the current inside the battery cell to supply power to other power-consuming structures.
[0038] As the capacity of single cells continues to increase, the number of electrode layers in the electrode assembly structure 4 is generally over 100. To facilitate electrode stacking, two electrode assembly structures 4 are usually first used to separate the layers, and then the two electrodes are combined into a core using a connecting piece. Finally, the other end of the connecting piece is laser welded to the electrode base 32 to achieve electrical connection.
[0039] However, when the two pole groups are combined to form a core, since the battery cell is long and the total length of the two pole groups is more than 1 meter, the equipment for the folding and combining process is difficult to operate, the production efficiency is extremely low, the yield is low, and the equipment development cost is very high.
[0040] like Figures 1 to 3As shown, in order to solve the above problems, in the battery cell structure provided by this embodiment, the cover plate 2 is provided with a welding hole 21, the pole assembly 3 includes a pole body 31 and a pole base 32, the pole body 31 is passed through the cover plate 2, and the pole base 32 is electrically connected to the pole body 31. Along the thickness direction of the cover plate 2, the pole base 32 blocks part of the welding hole 21; the pole group structure 4 includes two groups of pole group assemblies 41, the pole group assembly 41 includes a pole ear 411 and a pole group body 412, and the same-pole pole ears of the two pole group assemblies 41 constitute a pole ear group, and the two pole ears 411 of the pole ear group pass through the welding hole 21 and are fixedly connected to the side of the pole base 32 away from the pole group body 412.
[0041] In this cell structure, two sets of electrode group assemblies 41 can be stacked, and then the same-pole tabs 411 of the two sets of electrode group assemblies 41 are passed through the welding holes 21 and, after being bent, fixed to the side of the pole base 32 facing away from the pole group body 412, so that the current generated by the pole group assemblies 41 can be drawn out through the pole base 32 and the body. Connecting the same-pole tabs 411 of the two sets of electrode group assemblies 41 through the pole base 32 not only eliminates the process of folding and closing the core, but also reduces the difficulty of fixing the tabs 411 to the pole base 32, thereby improving efficiency and reducing costs.
[0042] Generally speaking, the electrode assembly 41 includes positive and negative tabs. The positive tabs of the two sets of electrode assembly assemblies 41 of the electrode assembly structure 4 form a positive tab group, and the negative tabs of the two sets of electrode assembly assemblies 41 form a negative tab group. In order to connect both the positive and negative tab groups to the external circuit, the battery cell structure includes two sets of pole assemblies 3. Therefore, the cover plate 2 is provided with two welding holes 21. The two sets of pole assemblies 3, the two welding holes 21, and the two sets of tab groups are arranged in a one-to-one correspondence. In other words, the pole base 32 of one set of pole assemblies 3 is connected to the two positive tabs of the positive tab group, and the pole base 32 of one set of pole assemblies 3 is connected to the two negative tabs of the negative tab group.
[0043] like Figure 2 and Figure 3 As shown, in order to facilitate the injection of electrolyte into the housing 1 , a liquid injection hole 24 is opened on the cover plate 2 , and the liquid injection hole 24 is located between the two welding holes 21 .
[0044] In this embodiment, the cell structure further includes end plates 5. The cover plate 2 and end plates 5 are disposed on opposite sides of the housing 1, and explosion-proof valves 51 are provided on the end plates 5. Because both sets of pole assemblies 3 are disposed on the cover plate 2, the installation of the explosion-proof valves 51 on the end plates 5 enables thermal and electrical separation. When thermal runaway of the cell structure causes the explosion-proof valves 51 to open, the electrical connection structure at the other end is not affected, thus preventing a more serious cascading thermal runaway. This reduces the impact of thermal runaway on the cell and improves the safety of the cell structure.
[0045] It is worth mentioning that the two groups of pole assemblies 3 have the same structure, and the positive and negative pole ears of the pole group assembly 41 are only electrically different, but the structure is also the same. For the sake of convenience of description, this embodiment takes a group of pole assemblies 3 and a group of pole ear groups of the pole group structure 4 as an example for explanation.
[0046] Generally, the tabs 411 are fixed to the pole base 32 by welding, which provides high connection reliability and is easy to operate. The two tabs 411 of the tab assembly pass through the welding holes 21 and are fixedly connected to the side of the pole base 32 facing away from the pole assembly body 412, allowing operators to weld the tabs 411 to the pole base 32 directly from the outside, preventing the pole assembly body 412 from obstructing the tabs 411.
[0047] like Figure 2 and Figure 3 As shown, the pole base 32 is disposed on the side of the cover plate 2 facing the pole group body 412, and the two tabs 411 of the tab group pass through the gap between the pole base 32 and the welding hole 21. This structure ensures that the position where the tabs 411 are welded to the pole base 32 is located within the welding hole 21 and does not protrude from the welding hole 21. This helps to ensure the flatness of the side of the cover plate 2 facing away from the pole group body 412 and also protects the welding position between the tabs 411 and the pole base 32.
[0048] To further protect the tabs 411 and the pole base 32, the cover plate 2 further includes a sealing plate 22, which is disposed within the welding hole 21 to cover the pole base 32. The sealing plate 22 is sealed to the welding hole 21. The sealing plate 22 can shield the tabs 411 and the pole base 32 for protection, and can also seal the cell structure to prevent moisture from entering the housing 1 and electrolyte leakage.
[0049] like Figure 3 As shown, the cover plate 2 is provided with a fixing groove 23, the sealing plate 22 is disposed in the fixing groove 23 and fixedly connected to the cover plate 2, and the welding hole 21 is provided on the bottom surface of the fixing groove 23. The structure of the fixing groove 23 can provide support and position limiting for the sealing plate 22, so that the sealing plate 22 does not contact the pole base 32 and the pole tab 411, thereby avoiding affecting the welding effect of the pole base 32 and the pole tab 411. Moreover, the structure of the fixing groove 23 can also increase the sealing area between the cover plate 2 and the sealing plate 22, thereby improving the sealing effect and sealing reliability.
[0050] In this embodiment, the two pole group bodies 412 are stacked, and along the stacking direction of the two pole group components 41 , the two pole tabs 411 of the pole tab group are spaced apart, and the two pole tabs 411 of the pole tab group pass through the welding hole 21 from opposite sides of the pole base 32 .
[0051] The two tabs 411 pass through the welding holes 21 on opposite sides of the pole base 32, so that the two tabs 411 do not directly contact each other, but are welded to the pole base 32 separately, avoiding mutual interference during welding and affecting the welding effect. The flat surface of the pole base 32 is fully utilized to increase the contact area between the tabs 411 and the pole base 32, thereby improving the connection strength during welding. It is worth noting that the distance between the two tabs 411 of the two sets of pole group bodies 412 is the same as the dimension of the pole base 32 along the stacking direction of the two pole group assemblies 41, so that the two tabs 411 do not need to be bent multiple times, which avoids affecting the performance of the tabs 411.
[0052] like Figure 3 As shown, a retaining rib 33 is protruded from the side of the pole base 32 facing away from the pole group body 412. The two tabs 411 of the tab group are respectively connected to the areas of the pole base 32 on both sides of the retaining rib 33. The provision of the retaining rib 33 is equivalent to dividing the plane where the pole base 32 and the tabs 411 are welded into two areas, each area being used for welding with a tab 411. The retaining rib 33 can provide a limit for the tabs 411. Even if the tabs 411 are long, the retaining rib 33 can separate the two tabs 411, preventing the two tabs 411 from contacting each other and affecting the welding effect. The retaining rib 33 also serves as a positioning function. The operator only needs to abut the tab 411 against the retaining rib 33. This can not only ensure the welding area, but also avoid consistency problems caused by the unstable welding position of the tabs 411.
[0053] In this embodiment, the two welding holes 21 are located between the pole bodies 31 of the two pole assemblies 3. This structure places the two welding holes 21 relatively close to the middle position, ensuring that the positive and negative tabs of the pole group assembly 41 face the two welding holes 21 and can be directly welded to the pole base 32.
[0054] To prevent the electrode pieces of the electrode assembly 41 from contacting the housing 1 and causing a short circuit, the electrode assembly structure 4 further includes an insulating film that covers the two electrode assembly assemblies 41. The insulating film not only isolates the electrode assembly body 412 from the housing 1, preventing short circuits and ensuring the normal operation of the battery cell structure, but also secures the two electrode assembly assemblies 41, tightly stacking the electrode pieces of the electrode assembly body 412 together, making the electrode assembly body 412 more compact and improving space utilization.
[0055] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there may be changes in the specific implementation methods and application scope. The content of this specification should not be understood as limiting the present invention.
Claims
1. A battery cell structure, characterized in that: include: A cover plate (2), wherein the cover plate (2) is provided with a welding hole (21); A pole assembly (3) comprising a pole body (31) and a pole base (32), wherein the pole body (31) is passed through the cover plate (2), the pole base (32) is electrically connected to the pole body (31), and along the thickness direction of the cover plate (2), the pole base (32) partially blocks the welding hole (21); A pole group structure (4) comprises two pole group assemblies (41), wherein the pole group assemblies (41) comprise pole tabs (411) and pole group bodies (412), the pole tabs of the same pole of the two pole group assemblies (41) forming a pole tab group, and the two pole tabs (411) of the pole tab group pass through the welding hole (21) and are fixedly connected to a side of the pole base (32) facing away from the pole group body (412).
2. The battery cell structure according to claim 1, characterized in that: The pole base (32) is arranged on a side of the cover plate (2) facing the pole group body (412), and the two pole tabs (411) of the pole tab group pass through the welding hole (21) through a gap between the pole base (32) and the welding hole (21).
3. The battery core structure according to claim 1, characterized in that: The cover plate (2) further comprises a sealing plate (22), wherein the sealing plate (22) is arranged in the welding hole (21) to cover the pole base (32).
4. The battery core structure according to claim 3, characterized in that: The cover plate (2) is provided with a fixing groove (23), the sealing plate (22) is arranged in the fixing groove (23) and fixedly connected to the cover plate (2), and the welding hole (21) is provided on the bottom surface of the fixing groove (23).
5. The battery core structure according to claim 1, characterized in that: Along the stacking direction of the two pole group assemblies (41), the two pole tabs (411) of the pole tab group are spaced apart, and the two pole tabs (411) of the pole tab group pass through the welding hole (21) from opposite sides of the pole base (32).
6. The battery cell structure according to claim 1, characterized in that: A retaining rib (33) is protruded from the side of the pole base (32) facing away from the pole group body (412), and the two pole tabs (411) of the pole tab group are respectively connected to areas of the pole base (32) located on both sides of the retaining rib (33).
7. The battery core structure according to claim 1, characterized in that: The pole group structure (4) further comprises an insulating film, wherein the insulating film is coated outside the two pole group components (41).
8. The battery cell structure according to any one of claims 1 to 7, characterized in that: The battery cell structure includes two groups of pole assemblies (3), the pole group structure (4) includes two groups of tab groups, the cover plate (2) is provided with two welding holes (21), and the two groups of pole assemblies (3), the two welding holes (21) and the two groups of tab groups are arranged in a one-to-one correspondence.
9. The battery core structure according to claim 8, characterized in that: The battery cell structure comprises a shell (1) and an end plate (5); the electrode group structure (4) is arranged in the shell (1); the cover plate (2) and the end plate (5) are respectively arranged on opposite sides of the shell (1); and an explosion-proof valve (51) is provided on the end plate (5).
10. A battery module, characterized in that: The battery module comprises a plurality of battery cell structures according to any one of claims 1 to 9, and the plurality of battery cell structures are connected in series or in parallel.