Battery, battery pack and electric equipment
By designing the folding ears and expanding welding zones in the bare cell structure, the problem of poor heat dissipation of existing square shell batteries is solved, significantly reducing the risk of thermal runaway.
Patent Information
- Application Number
- CN202420577695.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-25
- Publication Date
- 2025-06-10
- Estimated Expiration
- 2034-03-25
AI Technical Summary
The electrode welding structure of existing square shell batteries leads to poor heat dissipation effect, which in turn increases the risk of thermal runaway.
A bare electric core structure is designed, wherein the electrode ear includes a base section and a folded section, and the welding area is located at the folded section extends along the length of the electrode, so that the folded welding area is parallel to the first side of the electrode sheet, thereby enlarging the heat dissipation area of the electrode ear.
By expanding the heat dissipation area of the extreme ear, the probability of thermal runaway is reduced and the heat dissipation effect of the battery is improved.
Smart Images
Figure CN222966294U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, and particularly to a battery, a battery pack and an electrical equipment. Background Art
[0002] With the continuous popularization of electric vehicles, the battery pack is a core component of electric vehicles. Among them, the square shell battery is a very common type of battery and is widely used in electric vehicles. In the existing structure of the square shell battery, the electrode tabs on the stacked or soft-wound battery cores are stacked and then laser welded to the electrode posts. General welding will extend along the width direction of the electrode tab, the welding area is small, and the adjustment space is small. After the electrode tabs are welded, the structure is tightly fitted, which is not conducive to heat dissipation.
[0003] Therefore, a new technical solution is needed in this field to solve the above problems. Summary of the Utility Model
[0004] To solve the technical problem that the electrode tabs in the battery pack in the prior art cannot dissipate heat effectively. In a first aspect, the utility model provides a battery, including a housing; a bare battery core, the bare battery core is installed in the housing, the bare battery core includes electrode plates and electrode tabs extending from the first side of the electrode plates; the electrode tabs include a base section and a folded section, the welding area is located in the folded section and extends along the length direction of the electrode tab, and the length direction after the folded section is folded is parallel to the first side; a cover plate, the cover plate is provided with electrode posts; the folded section is connected to the electrode posts.
[0005] In an optional technical solution of the utility model, the electrode plates include a positive electrode plate and a negative electrode plate, the positive electrode plate and the negative electrode plate respectively extend positive electrode tabs and negative electrode tabs, and the folding directions of the folded sections of the positive electrode tab and the negative electrode tab are opposite.
[0006] In an optional technical solution of the utility model, the welding area is located in the middle of the width direction of the electrode tab.
[0007] In an optional technical solution of the utility model, the length of the welding area is 1.2 times to 3 times the width of the electrode tab.
[0008] In an optional technical solution of the utility model, the width of the welding area is 1 / 10 to 1 / 3 of the width of the electrode tab.
[0009] In an optional technical solution of the utility model, the electrode tab is welded to a connecting piece, and the electrode post (31) is welded to the connecting piece.
[0010] In an optional technical solution of the utility model, the battery includes a plurality of bare battery cores.
[0011] In an optional technical solution of the utility model, the cover plate further includes an explosion-proof valve and / or a liquid injection hole.
[0012] In a second aspect, the present utility model further provides a battery pack, which includes a plurality of the above-mentioned batteries.
[0013] In a third aspect, the present utility model further provides an electrical equipment, which includes the above-mentioned battery pack. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The preferred embodiments of the present utility model will be described below with reference to the drawings, in which:
[0015] Figure 1 is an exploded view of the structure of the battery provided by the present utility model;
[0016] Figure 2 is a schematic diagram of the bare cell structure of the battery provided by the present utility model;
[0017] Figure 3 for the present utility model Figure 2 is a partial enlarged view of the bare cell in the present utility model;
[0018] Figure 4 is a schematic diagram of the side structure of one kind of tab of the battery provided by the present utility model;
[0019] Figure 5 is a schematic diagram of the side structure of another kind of tab of the battery provided by the present utility model;
[0020] Figure 6 is a schematic diagram of the structure of one kind of electrode plate of the battery provided by the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] The preferred embodiments of the present utility model will be described below with reference to the drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principle of the present utility model and are not intended to limit the protection scope of the present utility model.
[0022] It should be noted that in the description of the present utility model, the terms indicating the direction or positional relationship such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the direction or positional relationship shown in the drawings. This is only for convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0023] In addition, it should be noted that in the description of the present utility model, unless otherwise clearly specified and defined, the terms "installation", "setting", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, indirectly connected through an intermediate medium, or the communication inside two components. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0024] As Figures 1 to 3 shown, the present utility model provides a battery, including: a housing 1 of the battery; a bare battery cell 2 that can be installed in the housing 1, the bare battery cell 2 including a pole piece 21 and a tab 22 extending from a first side 211 of the pole piece 21; the tab 22 extends outward from the first side 211 of the pole piece 21, the tab 22 includes a base section 221 and a folded section 222, a welding area 2221 is located in the folded section 222 and extends along the length direction of the tab 22, and the length direction of the folded section 222 after folding is parallel to the first side 211; a cover plate 3, and a pole column 31 is provided on the cover plate 3; the pole column 31 is connected to the bare battery cell 2 through the folded section 222 of the tab 22.
[0025] For the bare battery cell 2 of the battery of the present utility model, the extended tab 22 is folded along the first side 211, and the folding angle is half of the included angle between the extending direction and the first side. After the tab 22 is folded, a crease is formed, and the base section 221 and the folded section 222 are respectively located on both sides of the crease: the base section 221 is located on the side of the crease close to the pole piece 21 and is connected to the pole piece 21, and the folded section 222 is located on the side of the crease far from the pole piece 21. In this way, because the folding angle is half of the extending angle, the length direction of the folded section 222 after folding will be parallel to the first side 211. It should be noted that the parallel mentioned here is not strictly parallel in the mathematical sense, but from the perspective of actual setting, it is basically parallel or approximately parallel, so that the length direction of the folded section 222 after folding and the extending direction of the straight line where the first side 211 of the pole piece 21 is located are basically kept consistent, that is, both should be included in the parallel mentioned in the present utility model.
[0026] Specifically, as Figures 1 to 3 shown, the pole piece 21 of the bare battery cell 2 forms a multi-layer structure by winding or stacking, and multiple positive tabs or negative tabs extend from the same corresponding positions of the positive electrode plate or the negative electrode plate of the multi-layer bare battery cells 2; the multiple positive tabs or the multiple negative tabs are stacked on top of each other, and the multiple positive tabs or the multiple negative tabs at the base section 221 are bundled to the same position to form a tab bundle 22, and a folded with an inclination angle is performed from the end of the tab bundle 22, so that the length direction of the folded section 222 is parallel to the first side 211 of the pole piece 21, and the formed crease divides the base section 221 and the folded section 222.
[0027] The welding area 2221 will be welded along the length direction of the tab 22, such that the extending direction of the welding area 2221 is consistent with the length direction of the tab 22; it is clear that since the welding area 2221 is located in the folding section 222 and along [the relevant direction], the direction of the welding area 2221 after folding can be parallel to the first side 211 of the electrode tab 21. In this way, for a generally arranged terminal 31, the welding area 2221 can face the terminal 31.
[0028] According to the battery provided in the above solution of the present utility model, after the battery is bent, the tabs avoid being closely attached to each other, expanding the heat dissipation area of the tabs and reducing the probability of thermal runaway.
[0029] For a conventional bare battery cell 2, each electrode tab 21 and the tab 22 on the electrode tab 21 are formed by cutting the same foil material; in this way, the final shape of the foil material is a special-shaped polygon with one or more long strip small rectangular tabs 22 extending from a large rectangle. Specifically, usually, for a stacked bare battery cell 2, the positive electrode tab and the negative electrode tab are respectively stacked by multiple foil materials, and there is one tab 22 extending from each foil material; while for a wound bare battery cell 2, as Figure 6 shown, its positive electrode tab and negative electrode tab respectively have only one foil material, and there are multiple tabs 22 extending from this foil material. When this foil material is wound around the winding center, the multiple tabs 22 correspond to each other at the same position, forming a multi-layer state of the tabs 22.
[0030] The welding area 2221 is located in the middle of the width direction of the tab 22; in this way, the connection effect between the multi-layer tabs 22 is better, and at the same time, the connection of the welding area 2221 can also be stable enough.
[0031] Due to the difference in the distance from the center of the tab 22 when it converges, the lengths of the base segments 221 of the tabs 22 in different layers will be different.
[0032] As a specific embodiment of the present utility model, as Figure 4 shown, before the folding section 222 is folded, ultrasonic welding is performed on the multi-layer tabs 22, and the folding section 222 of the tab 22 will be welded separately. The welding process of this solution has a lower difficulty and higher reliability.
[0033] As a specific embodiment of the present utility model, as Figure 5 shown, after the folding section 222 is folded, ultrasonic welding is performed on the multi-layer tabs 22, and the folding section 222 and the base segment 221 will be welded together at the overlapping part of the two, that is, the triangular area shown as Figure 5 shown. In this case, the folded part will not be able to be opened, and the structure is more stable.
[0034] Optionally, the folding sections 222 of the positive tab and the negative tab are folded in opposite directions. As Figure 1As shown, under this solution, taking a square shell battery as an example, when the positive and negative electrode posts 31 of the square shell battery are located at the symmetric two ends of the same side, the folding directions of the folding sections of the positive electrode tab and the negative electrode tab of the battery in the present invention are opposite. After the positive and negative electrode tabs are folded, they are respectively opposite to the positive and negative electrode posts, and it is easier to realize the connection between the electrode tabs 22 and the electrode posts 31: the positions where the positive and negative electrode tabs extend from the positive and negative electrode plates can also be symmetric to each other. Such a setting does not require changing the cutting method of the foil material for manufacturing the electrode plate 21 in the prior art, and only adjusting the subsequent welding steps and processes can form the bare battery cell 2 required by the present invention.
[0035] Optionally, the folding sections 222 of the positive electrode tab and the negative electrode tab are folded in the same direction. After folding, the folding sections 222 of the positive and negative electrode tabs face the same direction. Under this solution, the process steps for folding and welding the electrode tabs 22 are simpler. The positive and negative folding and welding devices only need to perform automatic welding in the same operation in sequence.
[0036] The width of the welding area 2221 accounts for 1 / 10 to 1 / 3 of the width of the electrode tab 22. At this width, the connection between the electrode tabs 22 in each layer of the welding area 2221 is stable, and it has a good heat dissipation effect.
[0037] In the solution of the prior art mentioned in the foregoing part, the length of the welding area 2221 is limited by the width of the electrode tab 22, which is likely to cause poor heat dissipation and lead to thermal runaway. In the solution of the present invention, the expandable space of the welding area 2221 is large, and the electrode tabs 22 do not fit tightly, so the heat dissipation effect is better. When the length of the welding area 2221 exceeds 1.2 times the width of the electrode tab 22, the heat dissipation effect has been well improved. Optionally, the welding area 2221 should not exceed 3 times the width of the electrode tab 22 to reduce the waste of the foil material used for cutting.
[0038] Therefore, in an embodiment of the present invention, the length of the welding area 2221 is 1.2 times to 3 times the width of the electrode tab 22.
[0039] In an embodiment of the present invention, the battery includes one or more bare battery cells 2 in a parallel structure, and the folded electrode tabs 22 are connected to the positive and negative electrode posts 31 on the cover plate 3 by welding.
[0040] In an embodiment of the present invention, the electrode tabs 22 on the bare battery cell 2 and the electrode posts 31 on the cover plate 3 are connected by jointly welding to a connecting piece. Especially when multiple bare battery cells 2 are in parallel, the electrode tabs 22 of multiple bare battery cells 2 are jointly welded to the connecting piece, and then the connection is welded to the electrode post 31; or the welded electrode tabs 22 and the electrode post 31 are directly welded. This solution is more suitable when the battery only includes one bare battery cell 2; when only one bare battery cell 2 is arranged in the battery housing 1, the folding sections 222 of the positive and negative electrode tabs are directly welded to the positive and negative electrode posts 31 of the cover plate 3.
[0041] As a specific embodiment of the present utility model, as Figure 1 shown, the battery includes two bare battery cells 2, and the multi-layer tabs 22 of the positive and negative electrodes of the bare battery cells 2 are folded in different directions; at the same time, the folded positive tabs 22 of the two bare battery cells 2 are jointly welded to a connecting piece, and the folded negative tabs 22 are welded to another connecting piece, and these two connecting pieces are respectively connected to the positive and negative electrode posts 31 located on the battery cover 3.
[0042] In an embodiment of the present utility model, as Figure 1 shown, a liquid injection hole 33 and / or an explosion-proof valve 32 are further provided on the cover 3 of the battery. After the battery is filled with liquid, the liquid injection hole 33 is closed to complete the encapsulation; during the use of the battery, when the internal pressure reaches a certain level, the explosion-proof valve 32 will be opened to discharge gas, improving the safety performance of the battery.
[0043] So far, the technical solution of the present utility model has been described in combination with the preferred embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present utility model is obviously not limited to these specific embodiments. Without departing from the principle of the present utility model, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of the present utility model.
Claims
1. A battery, characterized in that: include: Housing (1); A bare battery cell (2), the bare battery cell (2) being installed in the housing (1), the bare battery cell (2) comprising a pole piece (21) and a pole ear (22) extending from a first edge (211) of the pole piece (21); the pole ear (22) comprising a base section (221) and a folded section (222); a welding area (2221) being located in the folded section (222) and extending along the length direction of the pole piece (21); and the length direction of the folded section (222) after folding is parallel to the first edge (211); A cover plate (3), wherein a pole (31) is provided on the cover plate (3); and the folded section (222) is connected to the pole (31).
2. The battery according to claim 1, characterized in that The electrode sheet (21) comprises a positive electrode sheet and a negative electrode sheet, the positive electrode sheet and the negative electrode sheet respectively extend a positive electrode ear and a negative electrode ear, and the folding directions of the folded sections (222) of the positive electrode ear and the negative electrode ear are opposite.
3. The battery according to claim 1, characterized in that The welding area (2221) is located in the middle of the width direction of the pole lug (22).
4. The battery according to claim 1, characterized in that The length of the welding area (2221) is 1.2 to 3 times the width of the pole tab (22).
5. The battery according to claim 1, characterized in that The width of the welding area (2221) is 1 / 10 to 1 / 3 of the width of the pole tab (22).
6. The battery according to claim 1, characterized in that The pole lug (22) is welded to the connecting piece, and the pole column (31) is welded to the connecting piece.
7. The battery according to claim 6, characterized in that The battery comprises a plurality of bare cells (2).
8. The battery according to claim 1, characterized in that The cover plate (3) further comprises an explosion-proof valve (32) and / or a liquid injection hole (33).
9. A battery pack, characterized in that: The invention comprises a plurality of batteries according to any one of claims 1 to 8.
10. An electrical device, characterized in that: include: The battery pack as claimed in claim 9.