Battery

Abstract

The present invention relates to the technical field of new energy batteries, and discloses a battery, which comprises: a battery cell assembly, which comprises a battery cell body and a tab, and the tab is arranged on at least one end of the battery cell body along a first direction; the connecting piece is arranged on one side of the battery cell body in the first direction and comprises a first area and a second area, the first area is used for being connected with a material plate, the first area is arranged on the edge of the second area in the second direction, and the tab is wound from the battery cell body to one side, deviating from the battery cell body in the first direction, of the second area; at least one part of the tab covers and is connected to the surface, deviating from the battery cell body, of the second region, and one part of the tab is located on at least one side of the connecting piece in the second direction; wherein the tab and the first region are not completely overlapped in the third direction. According to the invention, the risk of cutting the tab by the first area can be reduced, so that the overcurrent capability between the tab and the battery cell body is ensured, and the possibility of abnormal heating of the tab caused by current transmission blocking is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy batteries, and in particular to a battery. Background Art

[0002] In traditional battery manufacturing, the tabs are typically welded to the connector tabs by securing them to the underside of the tabs. This creates a large vertical gap between the tabs and the battery cell assembly, leading to low internal battery space utilization and limiting energy density. To improve vertical space utilization, the tabs are currently bent over the tabs for welding. However, this structural arrangement compromises current transmission between the tabs and the battery cell assembly, causing the tabs to heat up and even triggering thermal runaway. Summary of the Invention

[0003] The purpose of the present invention is to provide a battery that can reduce the risk of tabs being cut and improve the safety of the battery.

[0004] In order to achieve the above object, the present invention provides a battery comprising:

[0005] A battery cell assembly comprising a battery cell body and a tab, wherein the tab is arranged on at least one end of the battery cell body along a first direction;

[0006] a connecting piece disposed on one side of the cell body along the first direction, the connecting piece comprising a first region and a second region, the first region being disposed on an edge of the second region in the second direction, the tab extending from the cell body to a side of the second region facing away from the cell body along the first direction, at least a portion of the tab covering and connected to a surface of the second region facing away from the cell body, and a portion of the tab being located on at least one side of the connecting piece along the second direction;

[0007] Wherein, the tab and the first region do not completely overlap in the third direction;

[0008] The first direction, the second direction, and the third direction intersect with each other.

[0009] The present invention provides a battery, which has the following advantages compared with the prior art:

[0010] The battery of the present invention includes a cell assembly and a connecting piece, a cell body and a tab arranged on the cell body, the connecting piece includes a second area and a first area arranged on the second area, the first area and the tab are arranged on the same side of the second area, and the first area and the tab do not completely overlap, which can reduce the overlapping area of ​​the tab and the first area, reduce the contact area between the tab and the first area, and even make the first area and the tab spaced apart and not in contact with each other, thereby reducing the risk of the first area cutting the tab, thereby ensuring the overcurrent capacity between the tab and the cell body, reducing the possibility of abnormal heating of the tab due to obstruction of current transmission, and thus reducing the occurrence of thermal runaway of the battery and improving the safety of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Schematic diagram of the internal structure of a battery according to an embodiment of the present invention.

[0012] Figure 2 yes Figure 1 Enlarged schematic diagram of point A in the middle.

[0013] Figure 3 yes Figure 1 Cross-sectional view at CC.

[0014] Figure 4 yes Figure 3 Enlarged schematic diagram of point E in the middle.

[0015] Figure 5 It is a schematic diagram of the internal structure of a battery according to another embodiment of the present invention.

[0016] Figure 6 yes Figure 5 Enlarged schematic diagram of point B in the middle.

[0017] Figure 7 yes Figure 5 Cross-sectional view at DD in the middle.

[0018] Figure 8 yes Figure 7 Enlarged schematic diagram of point F in the middle.

[0019] Figure 9 yes Figure 7 An enlarged schematic diagram of the first zone of another embodiment at F in the middle.

[0020] Figure 10 It is a schematic structural diagram of a connecting piece according to an embodiment of the present invention.

[0021] Figure 11 yes Figure 10 Enlarged schematic diagram of point G in FIG.

[0022] In the figure, 1, battery cell assembly; 2, connecting piece; 11, battery cell body; 12, tab; 21, second area; 22, first area; 211, tab connection part; 212, pole connection part; Z, first direction; Y, second direction; X, third direction. DETAILED DESCRIPTION

[0023] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0024] In the description of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" and the like, 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 the present invention and simplify the description. They are not intended to 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 limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0026] Furthermore, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0027] For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] A battery according to an embodiment of the present invention includes a battery cell assembly 1 and a connecting sheet 2 .

[0029] The battery cell assembly 1 includes a battery cell body 11 and a tab 12 . The tab 12 is disposed on at least one end of the battery cell body 11 along a first direction X.

[0030] The battery cell body 11 includes a separator and two electrodes of opposite polarity, namely a positive electrode and a negative electrode. The cell body 11 operates by the movement of metal ions between the positive and negative electrodes. The cycle of the cell body 11 is the process of metal ions moving from the positive electrode to the negative electrode and then from the negative electrode to the positive electrode. The electrode includes a current collector and an active material layer, with the active material layer coated on the surface of the current collector. The tabs serve as the current output terminals of the cell and are either integrally connected to the positive or negative electrode or connected separately. The connection between the active material layer on the current collector and the tab is at the base of the tab. If the electrode is a positive electrode, the current collector can be made of aluminum, and the active material layer can be made of materials such as lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. If the electrode is a negative electrode, the current collector can be made of copper, and the active material layer can be made of materials such as carbon or silicon.

[0031] In this embodiment, the height direction of the battery housing is the first direction X, the width direction of the battery housing is the second direction Y, and the length direction of the battery housing is the third direction X. The first direction X, the second direction Y, and the third direction X intersect in pairs and are set to be perpendicular to each other in this embodiment, which means that the angle is 85° to 95°.

[0032] The battery cell assembly 1 and the connecting piece 2 are both arranged in the battery casing.

[0033] The battery cell assembly 1 also includes tabs 12, which are electrically connected to the electrode sheets. The positive tab 12 is electrically connected to the positive electrode sheet, and the negative tab 12 is electrically connected to the negative electrode sheet. The battery cell body 11 is charged and discharged through the positive and negative tabs 12. The tabs 12 are components formed by stacking and connecting the areas of the electrode sheets that are not coated with the positive active material layer, and are used to connect to the battery's poles.

[0034] The connecting piece 2 is arranged on one side of the battery cell body 11 along the first direction X. The connecting piece 2 includes a second area 21 and a first area 22. The first area 22 is used to connect to the material plate. The first area 22 is arranged on the edge of the second area 21 in the second direction Y. The pole tab 12 is wound from the battery cell body 11 to the side of the second area 21 away from the battery cell body 11 along the first direction X. At least a portion of the pole tab 12 covers and is connected to the surface of the second area 21 away from the battery cell body 11. A portion of the pole tab 12 is located on at least one side of the connecting piece 2 along the second direction Y.

[0035] Please refer to Figure 10 and Figure 11 The connection piece 2 is provided to facilitate the connection of the tab 12 to the pole, so that external equipment can be electrically connected to the battery housing through the pole. For the connection of the tab 12 and the pole of different polarities, a connection piece 2 is usually provided respectively.

[0036] In this embodiment, according to Figure 1In the viewing direction shown, the connecting piece 2 is arranged above the battery cell body 11. In order to improve the space utilization of the battery in the height direction, the tab 12 is bent from between the connecting piece 2 and the battery cell body 11 through one side of the connecting piece 2 to the top of the connecting piece 2, and the tab 12 covering the top of the connecting piece 2 is welded to the upper surface of the connecting piece 2.

[0037] The second area 21 is the main body of the connecting piece 2 , and the first area 22 is the material point on the connecting piece 2 , which is the structure remaining when the connecting piece 2 is cut out and used to connect the material plates.

[0038] The tab 12 and the first region 22 do not completely overlap in the third direction X.

[0039] Incomplete overlap may be partial overlap between the tab 12 and the first region 22. Figure 5 and Figure 6 Alternatively, the tab 12 and the first region 22 may be spaced apart from each other in the third direction X. Figure 1 and Figure 2 .

[0040] Due to manufacturing process limitations, before the connecting tab 2 is completely cut from the sheet, a material point exists on the outer edge of the connecting tab 2. This point, also known as the first region 22 in this embodiment, is the location for connection to the sheet. In the prior art, this point is completely covered by the tab 12, which can easily damage the tab 12, affecting the current transmission performance between the tab 12 and the battery cell assembly 1, causing the tab 12 to heat up, and even triggering thermal runaway of the battery.

[0041] Through such a structure, the overlapping area between the pole tab 12 and the first zone 22 can be reduced, the contact area between the pole tab 12 and the first zone 22 can be reduced, and even the first zone 22 and the pole tab 12 are spaced apart and not in contact with each other, thereby reducing the risk of the first zone 22 cutting the pole tab 12, thereby ensuring the current flow capacity between the pole tab 12 and the battery body 11, reducing the possibility of abnormal heating of the pole tab 12 due to obstruction of current transmission, and thus reducing the occurrence of battery thermal runaway and improving battery safety.

[0042] In some embodiments, please refer to Figure 7 and Figure 8 The tab 12 and the first region 22 partially overlap in the third direction X. The distance a between the tab 12 and the first region 22 in the third direction X is a mm, satisfying: 0.5≤a≤8. Preferably, a can be 0.2, 0.5, 1, 2.5, 4.1, 6, 8, 8.3, etc.

[0043] Due to process reasons, the first region 22 has more burrs on its structure than the second region 21. When a meets the above range, it can ensure the current carrying capacity of the tab 12 while reducing the risk of the tab 12 being cut. If the value is too small, the size of the tab 12 is small, and the connection area between the tab 12 and the connecting piece 2 and the connection area between the tab 12 and the battery body 11 is also small, affecting the current carrying performance of the tab 12. If the value is too large, the overlap between the tab 12 and the first region 22 in the third direction X will increase, increasing the possibility of contact and causing the tab 12 to be scratched and worn by the first region 22.

[0044] When measuring dimension a, you can use a common length measuring tool, such as a ruler or tape measure.

[0045] When measuring a, the end of the tab 12 close to the first region 22 in the third direction X is used as the reference edge. The distance between the edge of the end of the first region 22 covered by the tab 12 in the third direction X and the reference edge is measured using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the overlapping distance a mm between the tab 12 and the first region 22 in the third direction X.

[0046] The distance between the second area 21 in the third direction X is b mm, satisfying: 0.02≤a / b≤0.3. Optionally, a / b can be 0.01, 0.02, 0.15, 0.27, 0.3, 0.4, etc.

[0047] When a / b falls within the above range, the manufacturing difficulty of the connecting piece 2 is not too high, and the risk of the tab 12 being cut is reduced. If the value is too small, the processing difficulty of the connecting piece 2 increases, and it is difficult to control the manufacturing quality of the connecting piece 2, resulting in a decline in the manufacturing quality of the connecting piece 2, thereby affecting the current carrying capacity of the connecting piece 2. If the value is too large, the overlap between the tab 12 and the first region 22 in the third direction X increases, increasing the possibility of contact, resulting in an increased risk of the tab 12 being scratched and worn by the first region 22.

[0048] In addition, the distance b mm of the second area 21 in the third direction X also satisfies: 15≤b≤55. Optionally, b can be 12, 15, 20, 34, 50, 55, 60, etc.

[0049] When b satisfies the above range, it can ensure the welding area with the tab 12 and the current capacity between the connecting piece 2 and the tab 12, and also make the manufacturing difficulty of the connecting piece 2 not too high.

[0050] When measuring dimension b, you can use a common length measuring tool, such as a ruler or tape measure.

[0051] When measuring b, take the connecting piece 2 and use a length measuring tool to measure the distance between the two ends of the second area 21 in the third direction X. Measure multiple times and take the average value to obtain the distance b mm of the second area 21 in the third direction X.

[0052] The distance between the tabs 12 in the third direction X is c mm, satisfying: 0.05≤a / c≤0.3. Optionally, a / c can be 0.036, 0.05, 0.1, 0.21, 0.24, 0.3, 0.312, etc.

[0053] When a / c falls within the above range, the current carrying capacity of the tab 12 is ensured while reducing the risk of the tab 12 being cut. If the value is too small, the size of the tab 12 is reduced, and the connection area between the tab 12 and the connecting piece 2 and the cell body 11 is also reduced, affecting the current carrying performance of the tab 12. If the value is too large, the overlap between the tab 12 and the first region 22 in the third direction X increases, increasing the likelihood of contact and leading to an increased risk of scratching and abrasion of the tab 12 by the first region 22.

[0054] In addition, the distance between the tabs 12 in the third direction X is c mm, satisfying: 15≤c≤85. Optionally, c can be 11, 15, 20, 38, 41, 57, 66, 72, 80, 85, 88, etc.

[0055] When c satisfies the above range, the current carrying capacity will not be affected due to the size of the tab 12 being too small, nor will the overlapping size with the first area 22 be increased due to the size of the tab 12 being too large, thereby reducing the risk of the tab 12 being cut by the first area 22.

[0056] When measuring dimension c, you can use a common length measuring tool, such as a ruler or tape measure.

[0057] When measuring c, the distance between the two ends of the tab 12 in the third direction X is measured using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the distance c mm of the tab 12 in the third direction X.

[0058] In some embodiments, please refer to Figure 3 and Figure 4 The tab 12 and the first region 22 are spaced apart in the third direction X.

[0059] The first area 22 and the tab 12 are spaced apart and do not contact each other, which significantly reduces the risk of the first area 22 cutting the tab 12, thereby ensuring the overcurrent capacity between the tab 12 and the battery body 11, reducing the possibility of abnormal heating of the tab 12 due to obstruction of current transmission, and thus reducing the occurrence of battery thermal runaway and improving battery safety.

[0060] The distance between the tab 12 and the first region 22 in the third direction X is d mm, satisfying: 0.2≤d≤12. Optionally, d can be 0.1, 0.2, 1, 2.8, 4.7, 6, 8.4, 10, 11.3, 12, 12.5, etc.

[0061] When d falls within the above range, the tab 12 will not be too small, ensuring the current carrying capacity of the tab 12, while also reducing the risk of the tab 12 being cut. If the value is too small, the tab 12 will be smaller, and the connection area between the tab 12 and the connecting piece 2 and the cell body 11 will also be smaller, affecting the current carrying performance of the tab 12. If the value is too large, the tab 12 will be closer to the first region 22, increasing the risk of the tab 12 being cut.

[0062] When measuring dimension d, you can use a common length measuring tool, such as a ruler or tape measure.

[0063] When measuring d, the edge of the first region 22 close to the tab 12 in the third direction X is used as the reference edge. The distance between the edge of the tab 12 close to the first region 22 in the third direction X and the reference edge is measured using a length measuring tool. Multiple measurements are taken and the average value is taken to obtain the spacing distance d mm between the tab 12 and the first region 22 in the third direction X.

[0064] The second zone 21 includes a pole tab connection portion 211 and a pole column connection portion 212. At least a portion of the pole tab 12 covers and is connected to the pole tab connection portion 211. One end of the pole tab connection portion 211 in the third direction X is connected to the pole column connection portion 212. The first zone 22 is arranged on at least one side of the pole column connection portion 212 along the second direction Y.

[0065] The tab connection portion 211 is used to be covered by the tab 12 and welded to the tab 12, while the post connection portion 212 is used to connect to the post. In this embodiment, two tab connection portions 211 are provided, and one post connection portion 212 is provided. This is because two battery cell assemblies 1 are provided in this embodiment, and the tab 12 of each battery cell assembly 1 is connected to a tab connection portion 211. In other embodiments, other numbers of tab connection portions 211 may also be provided.

[0066] The distance between the tab connection portion 211 and the tab connection portion 211 in the second direction Y is e mm, satisfying: 5≤e≤24. Optionally, e can be 3, 5, 8, 11, 15, 17, 20, 24, 25, etc.

[0067] When e satisfies the above range, the current flow capacity between the tab 12 and the connecting piece 2 can be guaranteed while reducing the risk of the tab 12 being cut. If the value is too small, the size of the tab connection portion 211 is too small, and the connection area between the tab 12 and the battery cell body 11 is also small, which affects the current flow performance of the tab 12. If the value is too large, the overall size of the tab 12 is large, which will bring the tab 12 closer to the first area 22, increasing the risk of the tab 12 being cut.

[0068] When measuring dimension e, you can use a common length measuring tool, such as a ruler or tape measure.

[0069] When measuring e, take the connecting piece 2 and use a length measuring tool to measure the distance between the two ends of the tab connection part 211 in the second direction Y. Measure multiple times and take the average value to obtain the distance e mm of the tab connection part 211 in the second direction Y.

[0070] The overlapping distance between the second region 21 and the tab 12 in the third direction X is f mm, satisfying: 15≤f≤55. Optionally, f can be 13, 15, 20, 36, 49, 50, 55, 57, etc.

[0071] When f satisfies the above range, the second region 21 and the tab 12 can have a sufficient welding area, thereby ensuring the flow capacity between the connecting piece 2 and the tab 12.

[0072] When measuring dimension f, you can use a common length measuring tool, such as a ruler or tape measure.

[0073] When measuring f, first confirm the overlapping area between the tab 12 and the second region 21, and use a length measuring tool to measure the distance between the two ends of the overlapping area in the third direction X. Measure multiple times and take the average value to obtain the overlapping distance f mm between the second region 21 and the tab 12 in the third direction X.

[0074] In some embodiments, please refer to Figure 8 The first area 22 is located outside the second area 21 , and the first area 22 is located at the end edge of the second area 21 in the second direction Y.

[0075] In this embodiment, the shape of the first area 22 is a protrusion on the edge of the second area 21. Through such a structure, it is possible to ensure that the connecting piece 2 has a sufficient area, and the connection area between the tab 12 and the connecting piece 2 and the connection area between the tab 12 and the battery body 11 are guaranteed, thereby ensuring the flow capacity between the connecting piece 2 and the tab 12 and reducing the occurrence of problems such as excessive current density and local overheating due to insufficient area.

[0076] The distance between the tabs 12 in the third direction X is c mm, satisfying: 0.05≤a / c≤0.28. Optionally, a / c can be 0.042, 0.05, 0.09, 0.17, 0.21, 0.26, 0.28, 0.29, etc.

[0077] Since the first area 22 is set to a convex shape, it is easy to cut the tab 12. When a / c meets the above range, the risk of cutting the tab 12 is reduced while ensuring the current capacity of the tab 12.

[0078] In some embodiments, please refer to Figure 9 The first area 22 is located in the second area 21 , and the first area 22 is located at the end edge of the second area 22 in the second direction Y.

[0079] In this embodiment, the first region 22 is in the form of a recessed portion on the edge of the second region 21 . This structure can reduce the risk of cutting the tab 12 more than when the first region 22 is in the form of a protrusion.

[0080] The distance between the tabs 12 in the third direction X is c mm, satisfying: 0.07≤a / c≤0.3. Optionally, a / c can be 0.05, 0.07, 0.11, 0.16, 0.21, 0.24, 0.3, 0.35, etc.

[0081] Due to the shape of the recessed portion of the first region 22, although the risk of cutting the tab 12 is reduced, it may also cause material loss in the second region 21 itself, affecting the connection area between the tab 12 and the connecting piece 2 and the connection area between the tab 12 and the battery cell body 11. When a / c meets the above range, while reducing the risk of cutting the tab 12, the current capacity between the tab 12 and the connecting piece 2 can also be guaranteed.

[0082] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A battery, characterized in that: include: A battery cell assembly comprising a battery cell body and a tab, wherein the tab is arranged on at least one end of the battery cell body along a first direction; a connecting piece disposed on one side of the cell body along the first direction, the connecting piece comprising a first region and a second region, the first region being disposed on an edge of the second region in the second direction, the tab extending from the cell body to a side of the second region facing away from the cell body along the first direction, at least a portion of the tab covering and connected to a surface of the second region facing away from the cell body, and a portion of the tab being located on at least one side of the connecting piece along the second direction; Wherein, the tab and the first region do not completely overlap in the third direction; The first direction, the second direction, and the third direction intersect with each other.

2. The battery according to claim 1, wherein: The tab partially overlaps with the first region in the third direction, and the overlapping distance between the tab and the first region in the third direction is a mm, which satisfies the following: 0.5≤a≤8.

3. The battery according to claim 2, wherein: The distance between the second areas in the third direction is b mm, and the following conditions are satisfied: 0.02≤a / b≤0.

3.

4. The battery according to claim 2, wherein: The distance between the tabs in the third direction is c mm, satisfying the following: 0.05≤a / c≤0.

3.

5. The battery according to claim 1, wherein: The tabs are spaced apart from the first region in the third direction.

6. The battery according to claim 5, characterized in that: The spacing distance between the tab and the first region in the third direction is d mm, which satisfies the following: 0.2≤d≤12.

7. The battery according to claim 5, characterized in that: The second region includes a tab connection portion and a pole connection portion, wherein at least a portion of the tab covers and is connected to the tab connection portion, one end of the tab connection portion in the third direction is connected to the pole connection portion, and the first region is provided on at least one side of the pole connection portion in the second direction; The distance between the tab connection portions in the second direction is e mm, satisfying the following: 5≤e≤24.

8. The battery according to claim 5, characterized in that: An overlapping distance between the second region and the tab in the third direction is f mm, satisfying: 15≤f≤55.

9. The battery according to claim 2, characterized in that: The first region is located outside the second region, and the first region is located at an end edge of the second region in the second direction.

10. The battery according to claim 9, characterized in that: The distance between the tabs in the third direction is c mm, satisfying the following: 0.05≤a / c≤0.

28.

11. The battery according to claim 2, characterized in that: The first region is located within the second region, and the first region is located at an end edge of the second region in the second direction.

12. The battery according to claim 9, wherein: The distance between the tabs in the third direction is c mm, satisfying the following: 0.07≤a / c≤0.3.

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