A battery

Abstract

The application discloses a battery, comprising a bottom shell and a core package, the bottom shell is formed with a mounting cavity; the core package comprises a tab and a bare cell, the tab has opposite first and second ends, the first end of the tab is connected with the bottom shell and located in the mounting cavity, and the second end of the tab extends out of the mounting cavity and is connected with the bare cell. Compared with the prior art, the bottom shell and the tab are welded together first, and then the tab and the bare cell are connected, which simplifies the assembly process, does not affect the production process of the bare cell while welding the tab and the bottom shell, and after the bare cell is prepared, it is directly connected with the tab, and only one time of folding the tab can make the bare cell completely embedded in the mounting cavity, avoiding damage caused by multiple times of folding, and improving the overall stability and service life of the battery. At the same time, compared with multiple times of folding, one time of folding saves the space in the bottom shell, can install a larger volume of bare cell, and improves the energy density of the battery.

Description

Technical Field

[0001] This application relates to the field of new energy battery technology, and in particular to a battery. Background Technology

[0002] Lithium-ion batteries are the core power unit in portable electronic devices and the new energy field, and their energy density and structural efficiency directly affect the performance of end products. Currently, square hard-shell batteries are widely used due to their high mechanical strength and convenient assembly. Their structure includes a metal bottom shell, a cover plate, and built-in bare cells, with the cells electrically connected to the shell via tabs. Traditional assembly processes require step-by-step operations: first, the bare cell tabs are welded to metal conductors (such as nickel sheets); then, the entire assembly is placed into the bottom shell; and finally, the conductors are welded to the pads on the inner wall of the bottom shell for secondary fixation.

[0003] The above-mentioned process has significant bottlenecks: First, space utilization is limited, and the tabs need to be bent through multiple redundant sections, which increases the ineffective space inside the bottom shell, compresses the volume of the bare cells, and restricts the improvement of battery energy density; Second, reliability risks are prominent, and repeated bending can easily cause tab breakage or poor welding, and the additional welding process increases the complexity of the manufacturing process. Utility Model Content

[0004] In view of the shortcomings of the prior art, this application provides a battery that can simplify the assembly process, optimize the spatial layout and improve the connection reliability.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] A battery includes a bottom casing and a core pack, the bottom casing forming a mounting cavity; the core pack includes tabs and bare cells, the tabs having opposing first and second ends, the first end of the tabs being connected to the bottom casing and located within the mounting cavity, and the second end of the tabs extending out of the mounting cavity and connected to the bare cells.

[0007] In one embodiment, the bottom shell includes a main body and a welding part, the welding part is connected to the main body and protrudes from the main body, and the electrode lug is connected to the welding part.

[0008] In one embodiment, the welding part has a fixing groove, and the electrode tab is at least partially inserted into the fixing groove.

[0009] In one embodiment, the bottom shell includes a first side and a second side adjacent to each other in its circumference, the area of ​​the first side being smaller than the area of ​​the second side, and the tab being connected to the first side.

[0010] In one embodiment, the tab includes a first connecting portion, a bending portion, and a second connecting portion. The first connecting portion and the second connecting portion are respectively connected to opposite ends of the bending portion. The first connecting portion is connected to the bottom shell, and the second connecting portion is used to connect to the bare battery cell. The bending portion extends in a bent or flexed manner along the length direction of the tab.

[0011] In one embodiment, the bent portion is located inside the bottom shell.

[0012] In one embodiment, there are multiple electrodes connected to the same side of the bottom shell, or multiple electrodes connected to opposite sides of the bottom shell.

[0013] In one embodiment, along the length direction of the electrode tab, the length of the electrode tab is L1, the length of the electrode tab inside the bottom shell is L2, and the length of the bottom shell is L3, where L1 > L3 > L2, and 0.75L3 > L2; and / or

[0014] Along the width direction of the electrode tab, the length of the electrode tab is L4, and the length of the bottom shell is L5, wherein L4 < 0.5L5.

[0015] In one embodiment, the bottom shell is made of metal, and the thickness of the bottom shell is 0.05mm to 0.6mm.

[0016] In one embodiment, the bottom shell includes a bottom surface, a first side surface, and a second side surface. The bottom surface is connected to the first side surface at opposite ends along its length direction, and the bottom surface is connected to the second side surface at opposite ends along its width direction. The bottom surface, the first side surface, and the second side surface enclose the mounting cavity, and the electrode tab is connected to the first side surface.

[0017] The beneficial effects of this application are as follows: This application provides a battery, including a bottom shell and a core pack, wherein the bottom shell forms an mounting cavity; the core pack includes tabs and bare cells, the tabs having opposing first and second ends, the first end of the tabs being connected to the bottom shell and located within the mounting cavity, and the second end of the tabs extending out of the mounting cavity and connected to the bare cells. Compared with the prior art, this application first welds the bottom shell and the tabs together, and then connects the tabs and the bare cells. This operational sequence simplifies the assembly process. While welding the tabs and the bottom shell, the production process of the bare cells is not affected. Once the bare cells are ready, they are directly connected to the tabs, and only one fold is needed to fully embed the bare cells into the mounting cavity, avoiding damage caused by multiple folds and improving the overall stability and lifespan of the battery. At the same time, one fold saves space within the bottom shell compared to multiple folds, allowing for the installation of larger bare cells and increasing the battery energy density. In addition, this design reduces the number of steps in the assembly process, lowers production costs, improves production efficiency, ensures the reliability and safety of the battery during long-term use, and further meets the market demand for high-performance batteries. Attached Figure Description

[0018] Figure 1 A schematic diagram of the structure of a bottom shell according to this application is shown;

[0019] Figure 2 A cross-sectional schematic diagram of a bottom shell according to this application is shown;

[0020] Figure 3 It shows Figure 2 Enlarged view of point A in the image;

[0021] Figure 4 Another cross-sectional schematic diagram of a bottom shell according to this application is shown;

[0022] Figure 5 It shows Figure 4 Enlarged view of point B in the image;

[0023] Figure 6 This invention provides a schematic cross-sectional view of a bare battery cell during installation.

[0024] Figure 7 A top view schematic diagram of a bottom shell according to this application is shown;

[0025] Reference numerals: 1. Bottom shell; 11. Main body; 111. First side surface; 112. Second side surface; 113. Bottom surface; 12. Welding part; 121. Fixing groove; 13. Mounting cavity;

[0026] 2. Tab; 21. First connecting part; 22. Bending part; 23. Second connecting part; 3. Bare battery cell. Detailed Implementation

[0027] In this application, the terms "set up," "equipped with," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0028] The terms “center,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0030] See Figure 1 This application provides a battery including a bottom shell 1 and a core pack. The bottom shell 1 has a mounting cavity 13. The core pack includes tabs 2 and bare cells 3. The tabs 2 have opposing first and second ends. The first end of the tabs 2 is connected to the bottom shell 1 and located in the mounting cavity 13. The second end of the tabs 2 extends out of the mounting cavity 13 and is connected to the bare cells 3.

[0031] In practical applications, the tab 2 has a first end and a second end along its length. First, the first end is connected to the bottom shell 1. At this time, the second end of the tab 2 extends out of the mounting cavity 13. Then, the bare cell 3 is connected to the second end of the tab 2. The tab 2 is then folded over so that the bare cell 3 is folded into the mounting cavity 13. The bare cell 3 is located inside the bottom shell 1 and is electrically connected to the bottom shell 1 through the tab 2, thus forming a complete battery structure.

[0032] Compared to existing technologies, this application first welds the bottom shell 1 and the tab 2 together, and then connects the tab 2 to the bare cell 3. This operational sequence simplifies the assembly process. While welding the tab 2 and the bottom shell 1, the production process of the bare cell 3 is not affected. Once the bare cell 3 is ready, it is directly connected to the tab 2. Furthermore, only one fold of the tab 2 is needed to fully embed the bare cell 3 into the mounting cavity 13, avoiding damage caused by multiple folds and improving the overall stability and lifespan of the battery. Simultaneously, a single fold saves space within the bottom shell 1 compared to multiple folds, allowing for the installation of a larger bare cell 3 and increasing the battery's energy density. In addition, this design reduces the number of steps in the assembly process, lowers production costs, improves production efficiency, ensures the reliability and safety of the battery during long-term use, and further meets the market's demand for high-performance batteries.

[0033] See again Figure 1 The bottom shell 1 includes a first side 111 and a second side 112 that are adjacent to each other along its circumference. The area of ​​the first side 111 is smaller than the area of ​​the second side 112. The tab 2 is connected to the first side 111.

[0034] In practical applications, the bottom shell 1 usually adopts a rectangular structure. The first side 111 and the second side 112 correspond to the short side and long side of the bottom shell 1, respectively. The electrode 2 is connected to the first side 111, which corresponds to the end of the bare cell 3 along its length direction.

[0035] The bare cell 3 is usually a wound or laminated cell. Taking the laminated cell as an example, in the laminated cell, although each electrode is independent, in order to obtain good current distribution and low resistance, the foil edges of all electrodes of the same polarity (usually located on both sides of the stack length direction) are usually aligned and welded (or ultrasonically welded) to one or more common tabs 2. These tabs 2 are naturally located at both ends of the stack length direction.

[0036] Therefore, connecting the tab 2 to the first side 111 of the base shell 1 not only facilitates the connection of the bare cell 3 along its length to the tab 2, but also ensures the optimization of the current path, reduces internal resistance, and improves the energy density and charge / discharge efficiency of the battery.

[0037] See again Figure 1 The bottom shell 1 also includes a bottom surface 113, with a first side surface 111 connected to each of the opposite ends of the bottom surface 113 along its length direction, and a second side surface 112 connected to each of the opposite ends of the bottom surface 113 along its width direction. The bottom surface 113, the first side surface 111, and the second side surface 112 enclose and form a mounting cavity 13, and the electrode ear 2 is connected to the first side surface 111.

[0038] In practical applications, the bottom surface 113, the first side surface 111, and the second side surface 112 enclose a mounting cavity 13 with one end open. The tab 2 is connected to the first side surface 111 and extends out from the opening of the mounting cavity 13. The bare cell 3 is connected to the end of the tab 2 that extends out of the mounting cavity 13. After the bare cell 3 and the tab 2 are connected, the tab 2 is bent so that the bare cell 3 flips into the mounting cavity 13 from the opening, ensuring that the bare cell 3 is stably embedded without damaging the internal structure, further improving the convenience of assembly and the overall performance of the battery.

[0039] See Figure 2 The bottom shell 1 includes a main body 11 and a welding part 12. The welding part 12 is connected to the main body 11 and protrudes from the main body 11. The electrode tab 2 is connected to the welding part 12.

[0040] In practical applications, to improve battery convenience and reduce resistance, the bottom shell 1 is usually made of a relatively thin thickness. When the tabs 2 are welded to the bottom shell 1, the high temperature generated during welding may cause the bottom shell 1 to deform or decrease in strength. Therefore, this application provides a welding part 12 to locally increase the thickness of the bottom shell 1. The protruding welding part 12 design effectively isolates the effects of high temperature, protects the structural integrity of the main body 11, ensures a firm weld, and does not affect the overall performance of the bottom shell 1. Thus, while ensuring battery safety, welding efficiency is improved. The tight connection between the tabs 2 and the welding part 12...

[0041] See Figure 3 The welding part 12 has a fixing groove 121, and the electrode 2 is at least partially inserted into the fixing groove 121.

[0042] In practical applications, during welding, the tab 2 is inserted into the fixing groove 121. The fixing groove 121 limits the relative position of the tab 2 and the welding part 12, and ensures that the tab 2 will not shake during welding, thereby improving the accuracy and stability of welding, reducing welding defects, and further improving the overall reliability and service life of the battery.

[0043] See Figure 4 and Figure 5 The tab 2 includes a first connecting part 21, a bending part 22 and a second connecting part 23. The two ends of the bending part 22 are respectively connected to the first connecting part 21 and the second connecting part 23. The first connecting part 21 is connected to the bottom shell 1, and the second connecting part 23 is used to connect the bare battery cell 3. The bending part 22 extends or bends along the length direction of the tab 2.

[0044] In practical applications, the tab 2 needs to be bent before assembly. The first connecting part 21 is connected to the bottom shell 1, and the second connecting part 23 is connected to the bare cell 3. The design of the bending part 22 allows the tab 2 to be bent into place in one go, improving bending efficiency, avoiding fatigue damage caused by multiple bends, ensuring the stability and reliability of the tab 2 connection, extending battery life, and improving overall assembly efficiency.

[0045] See again Figure 5 The bent portion 22 is located inside the bottom shell 1. In practical applications, the bent portion 22 of the tab 2 should be located inside the bottom shell 1, so that when the tab 2 is bent, the bent portion 22 of the tab 2 will not be exposed, thus avoiding affecting the overall assembly of the battery.

[0046] In one embodiment, there can be multiple electrodes 2 connected to the same side of the bottom shell 1, or multiple electrodes 2 connected to opposite sides of the bottom shell 1 respectively.

[0047] In practical applications, tab 2 is typically divided into positive tab 2 and negative tab 2. Positive tab 2 connects to the positive terminal of bare cell 3, and negative tab 2 connects to the negative terminal of bare cell 3, ensuring a clear current transmission path and reducing the risk of internal short circuits. Both tabs 2 can be connected to the same side of the bottom shell 1, which helps reduce the volume occupied by the bottom shell 1, allowing for the adaptation of larger bare cells 3 and improving battery energy density. If the tabs 2 are connected to opposite sides of the bottom shell 1, it helps to balance the current distribution, reduce the risk of local overheating, and enhance battery safety.

[0048] See again Figure 4 Along the length direction of the tab 2, the length of the tab 2 is L1, the length of the tab 2 inside the bottom shell 1 is L2, the length of the bottom shell 1 is L3, L1>L3>L2, 0.75L3>L2.

[0049] In practical applications, the length L2 of the tab 2 within the base shell 1 needs to be precisely controlled to ensure that the tab 2 does not occupy excessive space after bending. L2 should only cover the necessary current conduction area to avoid redundancy of the tab 2 within the base shell 1. Therefore, the length of L2 is limited to less than 0.75L3, which ensures current transmission efficiency while effectively utilizing the space in the base shell 1. For example, L2 can be 0.7L3, 0.65L3, 0.6L3, 0.55L3, etc., and the specific value can be adjusted according to actual assembly requirements.

[0050] Meanwhile, the tab 2 needs to be reserved outside the bottom shell 1, so L3 is smaller than L1, to ensure that there is still enough space to connect the bare chip after the tab 2 goes out of the bottom shell 1.

[0051] See Figure 6After the bare cell 3 is bent once by the tab 2, it is installed into the bottom shell 1. At this time, the length of L1-L2 should be less than or equal to L3 to ensure that the length of the tab 2 after bending can be accommodated by the bottom shell 1.

[0052] See Figure 7 Along the width direction of the tab 2, the length of the tab 2 is L4, and the length of the bottom shell 1 is L5, where L4 < 0.5L5.

[0053] To describe clearly, Figure 6 The X direction indicates the width direction of tab 2. In practical applications, when the positive and negative tabs 2 need to be mounted on the same side, the bottom shell 1 should have a sufficient width L5 to ensure that the tabs 2 arranged side by side (L4) will not interfere with each other, while facilitating assembly operations, avoiding the risk of short circuits caused by insufficient spacing between tabs 2, and improving the reliability and safety of battery assembly. Therefore, the value of L4 should comprehensively consider the number of tabs 2 and the width of the bottom shell 1 to ensure that there is an appropriate gap between tabs 2. For example, L4 can be 0.4L5, 0.3L5, 0.2L5, 0.1L5, etc.

[0054] In one embodiment, the bottom shell 1 is made of metal, and the thickness of the bottom shell 1 is 0.05mm to 0.6mm.

[0055] In practical applications, the bottom shell 1 is responsible for transmitting the current of the bare battery cell 3 to the outside, so the bottom shell 1 needs to be made of a conductive material, such as metal.

[0056] It should be noted that material thickness refers to the nominal thickness of the raw material. Limiting the material thickness to between 0.05mm and 0.6mm allows for lightweight design while ensuring sufficient mechanical strength and conductivity. For example, the material thickness can be 0.1mm, 0.2mm, 0.3mm, etc., and the specific value needs to be determined based on the battery capacity and structural strength requirements.

[0057] In one embodiment, the length of the bottom shell 1 can be 5mm to 100mm, the width can be 5mm to 100mm, and the thickness can be 1mm to 20mm. In this case, the length of the tab 2 can be 1mm to 50mm, the width can be 1mm to 20mm, and the thickness can be 0.03mm to 0.5mm.

[0058] In practical applications, the dimensions of the bottom shell 1 need to be flexibly adjusted according to the overall battery design to ensure the matching degree between the tab 2 and the bottom shell 1, optimize the current transmission path, and improve battery performance. The thickness of the tab 2 needs to balance conductivity and flexibility, avoiding excessive thickness that affects assembly or excessive thinness that leads to breakage. For example, when the length of the bottom shell 1 is 100mm and the width is 50mm, the length of the tab 2 can be 20mm, the width 10mm, and the thickness 0.1mm. This ensures both conductivity and ease of assembly and structural stability. Through precise design, space utilization can be maximized, improving the overall battery efficiency.

[0059] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0060] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0061] The above description is only a specific embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A battery, characterized in that, include: The bottom shell has a mounting cavity. The core package includes tabs and bare cells. The tabs have opposing first and second ends. The first end of the tab is connected to the bottom shell and located within the mounting cavity. The second end of the tab extends out of the mounting cavity and is connected to the bare cells.

2. The battery according to claim 1, characterized in that, The bottom shell includes a main body and a welding part. The welding part is connected to the main body and protrudes from the main body. The electrode lug is connected to the welding part.

3. The battery according to claim 2, characterized in that, The welding part has a fixing groove, and the electrode tab is at least partially inserted into the fixing groove.

4. The battery according to claim 1, characterized in that, The bottom shell includes a first side and a second side adjacent to each other along its circumference, the area of ​​the first side being smaller than the area of ​​the second side, and the tab being connected to the first side.

5. The battery according to claim 1, characterized in that, The tab includes a first connecting part, a bending part, and a second connecting part. The first connecting part and the second connecting part are respectively connected to opposite ends of the bending part. The first connecting part is connected to the bottom shell, and the second connecting part is used to connect the bare battery cell. The bending part extends or bends along the length direction of the tab.

6. The battery according to claim 5, characterized in that, The bent portion is located inside the bottom shell.

7. The battery according to any one of claims 1 to 5, characterized in that, The number of electrodes is multiple, and the multiple electrodes are connected to the same side of the bottom shell, or the multiple electrodes are respectively connected to opposite sides of the bottom shell.

8. The battery according to any one of claims 1 to 5, characterized in that, Along the length direction of the electrode tab, the length of the electrode tab is L1, the length of the electrode tab inside the bottom shell is L2, the length of the bottom shell is L3, L1 > L3 > L2, 0.75L3 > L2; and / or Along the width direction of the electrode tab, the length of the electrode tab is L4, and the length of the bottom shell is L5, wherein L4 < 0.5L5.

9. The battery according to any one of claims 1 to 5, characterized in that, The bottom shell is made of metal, and the thickness of the bottom shell is 0.05mm to 0.6mm.

10. The battery according to any one of claims 1 to 5, characterized in that, The bottom shell includes a bottom surface, a first side surface, and a second side surface. The bottom surface is connected to the first side surface at opposite ends along its length direction, and the bottom surface is connected to the second side surface at opposite ends along its width direction. The bottom surface, the first side surface, and the second side surface together form the mounting cavity, and the electrode tab is connected to the first side surface.

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