Battery cell and battery pack

Abstract

The utility model provides a battery cell and a battery pack. The battery cell comprises a shell, and at least one end of the shell is provided with a cover plate assembly; the pole group is arranged in the shell, at least one end of the pole group is provided with a pole lug, and the pole lug is connected with the cover plate assembly; the tab comprises a vertical extension part extending from the end face of the pole group to the cover plate assembly, the cover plate assembly comprises a pole welding table extending from the end face of the cover plate assembly to the pole group, and the vertical extension part is connected with the pole welding table. According to the battery cell, the pole group is matched with the shell, the tabs of the pole group are vertically led out, the problem that the tabs in an original structure are prone to wrinkling and tearing is solved, meanwhile, the tabs at the ends of the pole group are directly connected with the pole welding table of the cover plate assembly, end plates in the original structure are omitted, the number of overall parts is reduced, and the cost is reduced. And the number of parts is reduced, so that the internal space of the shell 1 is saved, and the capacity of the battery cell is further improved.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and in particular to a battery cell and a battery pack. Background Art

[0002] As lithium-ion battery technology matures, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields, and the requirements for the performance and safety of lithium-ion batteries are increasing. Lithium cells are the core components of battery pack safety and assembly, and their structural design is crucial to cell safety.

[0003] There are a large number of structural parts in the existing battery cells, which occupy a large space and have a great impact on the capacity of the battery cells, which is specifically reflected in the following aspects: First, the existing battery cells mostly use the connecting plate process, which leads to more parts and relatively complex process; second, if the direct welding process is adopted, the pole ear generally needs to adopt C-type or S-type bending, which will increase the length of the pole ear and increase the risk of wrinkles and tears; third, the existing blade battery cell positive electrode must adopt an end plate structure, which adds a part, and the process flow and cost will increase accordingly.

[0004] Therefore, it is necessary to design a battery cell to solve the above problems. Utility Model Content

[0005] In view of this, in order to overcome the defects of the prior art, the utility model provides a battery cell and a battery pack, which effectively solves the problem that the existing battery cells have a large number of structural parts, occupy a large space, and have a great impact on the capacity of the battery cells.

[0006] According to the first aspect of the utility model, a battery cell is provided, wherein the battery cell includes a shell, at least one end of the shell is provided with a cover plate assembly; a pole group is arranged inside the shell, at least one end of the pole group is provided with a pole ear, and the pole ear is connected to the cover plate assembly; the pole ear includes a vertical extension portion extending from the end face of the pole group toward the cover plate assembly, the cover plate assembly includes a pole column welding base extending from the end face of the cover plate assembly toward the pole group, and the vertical extension portion is connected to the pole column welding base.

[0007] Preferably, the pole lug further comprises a connecting platform portion, the connecting platform portion comprises a first platform surface and a second platform surface facing away from each other, the first platform surface is connected to the end surface of the pole group, and the second platform surface is provided with the vertical extension portion.

[0008] Preferably, the vertical extension portion divides the second table surface into a first inclined surface and a second inclined surface, the end of the pole welding platform is close to the second inclined surface, and the pole welding platform is welded to the vertical extension portion.

[0009] Preferably, a length of the second inclined surface in the first direction is smaller than a length of the first inclined surface in the first direction.

[0010] Preferably, the cover plate assembly further comprises a plate body and a pole body, the pole body passes through the plate body, and the pole body is connected to the pole lug through the pole welding platform.

[0011] Preferably, the pole welding platform is formed as an L-shaped component, and the pole welding platform includes a horizontal plate portion connected to the vertical extension portion and a vertical plate portion connected to the pole body, and the horizontal plate portion is perpendicular to the vertical plate portion.

[0012] Preferably, the length of the transverse plate portion in the second direction is greater than the length of the vertical extending portion in the second direction.

[0013] Preferably, the battery cell further comprises a side plate and mylar, wherein the mylar is arranged on the outer periphery of the electrode group, and the side plate is arranged between the shell and the mylar.

[0014] Preferably, a distance between the pole body and the first end of the shell in the third direction is smaller than a distance between the pole body and the second end of the shell in the third direction.

[0015] According to a second aspect of the present invention, a battery pack is provided, wherein the battery pack comprises the battery cell as described above.

[0016] According to the battery cell of the utility model, the pole ear of the pole group is vertically led out through the cooperation of the pole group and the shell, thereby avoiding the problem that the pole ear in the original structure is prone to wrinkles and tears. At the same time, the pole ear at the end of the pole group is directly connected to the pole welding base of the cover plate assembly, eliminating the end plate in the original structure, reducing the overall number of parts and the number of assembly steps. Due to the reduction in the number of parts, the space inside the shell 1 is also saved, thereby increasing the capacity of the battery cell.

[0017] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 An exploded view of a battery cell according to an embodiment of the present utility model is shown;

[0020] Figure 2 Another exploded view of a battery cell according to an embodiment of the present utility model is shown;

[0021] Figure 3 A schematic structural diagram of a cover plate assembly according to an embodiment of the utility model is shown;

[0022] Figure 4 A front view of a battery cell according to an embodiment of the utility model is shown;

[0023] Figure 5 The embodiment according to the utility model is shown Figure 4 A cross-sectional view at AA;

[0024] Figure 6 The embodiment according to the utility model is shown Figure 5 An enlarged schematic diagram of the structure at C;

[0025] Figure 7 A side view of a battery cell according to an embodiment of the present utility model is shown;

[0026] Figure 8 The embodiment according to the utility model is shown Figure 7 Cross-sectional view at BB.

[0027] Figure markings: 1-shell; 101-first end; 102-second end; 2-pole group; 3-pole ear; 301-vertical extension portion; 302-connecting platform; 303-first table; 304-first inclined plane; 305-second inclined plane; 306-second table; 4-cover plate assembly; 5-pole welding platform; 501-horizontal plate portion; 502-vertical plate portion; 6-plate body; 7-pole body; 8-side plate; 9-mylar; 10-weld mark; S1-first direction; S2-second direction; S3-third direction. DETAILED DESCRIPTION

[0028] The following specific embodiments are provided to help the reader obtain a comprehensive understanding of the methods, devices and / or systems described herein. However, after understanding the disclosure of the present application, various changes, modifications and equivalents of the methods, devices and / or systems described herein will be apparent. For example, the order of operations described herein is merely an example, and is not limited to the order set forth herein, but in addition to the operations that must occur in a particular order, changes that will be apparent after understanding the disclosure of the present application may be made. In addition, in order to improve clarity and brevity, descriptions of features known in the art may be omitted.

[0029] The features described herein may be implemented in different forms and should not be interpreted as being limited to the examples described herein. Rather, the examples described herein have been provided only to illustrate some of the many possible ways of implementing the methods, devices and / or systems described herein that will be apparent after understanding the disclosure of the present application.

[0030] Throughout the specification, when an element (such as a layer, a region, or a substrate) is described as being “on”, “connected to”, “bound to”, “over”, or “covering” another element, it may be directly “on”, “connected to”, “bound to”, “over”, or “covering” another element, or one or more other elements may be present between them. In contrast, when an element is described as being “directly on”, “directly connected to”, “directly bound to”, “directly over”, or “directly covering” another element, there may be no other elements present between them.

[0031] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more items.

[0032] Although terms such as "first," "second," and "third" may be used herein to describe various members, components, regions, layers, or portions, these members, components, regions, layers, or portions are not limited by these terms. Rather, these terms are only used to distinguish one member, component, region, layer, or portion from another member, component, region, layer, or portion. Therefore, without departing from the teachings of the examples described herein, the first member, component, region, layer, or portion referred to may also be referred to as the second member, component, region, layer, or portion.

[0033] For ease of description, spatial relational terms such as "above", "upper", "below", and "lower" may be used herein to describe the relationship of one element to another element as shown in the accompanying drawings. Such spatial relational terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. For example, if the device in the accompanying drawings is turned over, an element described as being "above" or "upper" relative to another element will subsequently be "below" or "lower" relative to the other element. Therefore, the term "above" includes both "above" and "below" orientations depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relational terms used herein will be interpreted accordingly.

[0034] The terms used herein are only used to describe various examples and are not used to limit the examples. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms "include", "comprising" and "having" list the existence of the stated features, quantities, operations, components, elements and / or their combinations, but do not exclude the existence or addition of one or more other features, quantities, operations, components, elements and / or their combinations.

[0035] Variations in the shapes shown in the drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the drawings but include variations in shapes that occur during manufacturing.

[0036] The features of the examples described herein may be combined in various ways that will be apparent after understanding the disclosure of the present application. In addition, although the examples described herein have various configurations, other configurations are possible as will be apparent after understanding the disclosure of the present application.

[0037] According to a first aspect of the present invention, a battery cell is provided, such as Figures 1 to 8 As shown, the battery cell can be used in electric vehicles and energy storage fields, and the battery cell includes a shell 1 and a pole group 2.

[0038] In the following description, reference will be made to Figures 1 to 8 The detailed structure of the shell 1 and the electrode group 2 of the battery cell is specifically described. In addition, in the description of the embodiment, three directions are also involved, namely the first direction S1, the second direction S2 and the third direction S3. The first direction S1 can be understood as Figure 5 The second direction S2 can be understood as the bottom-to-top direction in Figure 5 From right to left, the first direction S1 is perpendicular to the second direction S2; the third direction S3 can be understood as Figure 8 In addition, if Figure 5 and Figure 8 As shown in FIG. 1 , the positive and negative electrode structures of the battery cell are the same, so in the following description, Figure 5 and Figure 8 The right side of the diagram describes an example.

[0039] like Figure 1 , Figure 2 , Figure 5 and Figure 6As shown, at least one end of the shell 1 is provided with a cover assembly 4. Preferably, in the embodiment, both ends of the shell 1 are provided with a cover assembly 4, that is, the shell 1 and the cover assembly 4 provided at both ends can form a symmetrical structure. The pole group 2 is arranged inside the shell 1, and at least one end of the pole group 2 is provided with a pole ear 3, and the pole ear 3 is connected to the cover assembly 4. Preferably, in the embodiment, both ends of the pole group 2 are provided with a pole ear 3. Since the pole ear 3 is directly connected to the cover assembly 4, there is no need to install the end plate in the original structure, thereby saving the internal space of the shell 1, and then a pole group with larger capacity and larger volume can be installed, thereby improving the capacity of the battery cell. The positive and negative poles (both ends of the shell 1) of the battery cell are directly connected to the cover assembly 4 through the pole ear 3, which reduces the number of parts. Due to the reduction of the process flow, the cost will be reduced accordingly, and the space occupied is small, further improving the capacity of the battery cell.

[0040] like Figure 1 , Figure 2 , Figure 5 and Figure 6 As shown, in the embodiment, the pole lug 3 includes a vertical extension portion 301 extending from the end face of the pole group 2 toward the cover plate assembly 4, and the cover plate assembly 4 includes a pole column welding platform 5 extending from the end face of the cover plate assembly 4 toward the pole group 2. The vertical extension portion 301 is connected to the pole column welding platform 5, and the connection method can be welding to achieve direct connection between the pole lug 3 and the cover plate assembly 4. The vertical extension portion 301 of the pole lug 3 is vertically led out and does not need to be bent (the shape commonly used before is C-shaped or S-shaped bending), so the length of the pole lug 3 is reduced, and the risk of wrinkles and tears in the pole lug 3 is avoided. The vertical extension portion 301 is directly connected to the pole column welding platform 5, and the connecting piece in the original structure is cancelled, which further saves the space of the battery cell.

[0041] The pole lug 3 of the battery cell is led out vertically, which avoids the risk of wrinkles and tears on the pole lug 3. At the same time, the pole lug 3 at the end of the pole group 2 is directly connected to the pole welding base 5 of the cover plate assembly 4, which reduces the overall number of parts, reduces the assembly steps, saves space inside the shell 1, and improves the capacity of the battery cell.

[0042] Preferably, if Figure 5 and Figure 6 As shown, in the embodiment, the pole tab 3 may further include a connecting platform 302, and the connecting platform 302 and the vertical extension portion 301 together constitute the pole tab 3. The connecting platform 302 includes a first platform 303 and a second platform 306 facing each other, the first platform 303 is connected to the end surface of the pole group 2, and the connection method may be welding, and the second platform 306 is provided with a vertical extension portion 301. The length of the connecting platform 302 in the first direction S1 is relatively long, so that the pole tab 3 can be stably arranged on the end surface of the pole group 2, and the welding operation is also convenient.

[0043] Preferably, if Figure 5 and Figure 6 As shown, in the embodiment, the vertical extension portion 301 divides the second platform 306 into a first inclined surface 304 and a second inclined surface 305, the end of the pole welding platform 5 is close to the second inclined surface 305, and the pole welding platform 5 is welded to the vertical extension portion 301. The vertical extension portion 301 divides the connecting platform 302 into two parts, wherein the part where the second inclined surface 305 is located is used to accommodate the end of the pole welding platform 5, and the part where the second inclined surface 305 is located can be understood as a clamping position, which is convenient for welding the pole welding platform 5 and the vertical extension portion 301. The arrangement of the first inclined surface 304 and the second inclined surface 305 can make the vertical extension portion 301 not easy to bend, and can further reduce the weight while making the vertical extension portion 301 have sufficient strength.

[0044] Preferably, if Figure 5 and Figure 6 As shown, in the embodiment, the length of the second inclined surface 305 in the first direction S1 is less than the length of the first inclined surface 304 in the first direction S1. Since the length of the end of the pole welding platform 5 in the first direction S1 is shorter, the length of the second inclined surface 305 in the first direction S1 can match the length of the end of the pole welding platform 5 in the first direction S1, which is convenient for welding.

[0045] Preferably, if Figures 3 to 6 As shown, in the embodiment, the cover plate assembly 4 may further include a plate body 6 and a pole body 7, the pole body 7 penetrates the plate body 6, and the pole body 7 is connected to the pole ear 3 through the pole welding platform 5. The plate body 6 may be, for example, a bare aluminum plate, which plays a role of conducting and connecting. The pole body 7 is used to conduct current and connect the battery cell.

[0046] Preferably, if Figures 3 to 6 As shown, in the embodiment, the pole welding platform 5 is formed as an L-shaped component, and the pole welding platform 5 includes a horizontal plate portion 501 connected to the vertical extension portion 301 and a vertical plate portion 502 connected to the pole body 7, and the horizontal plate portion 501 is perpendicular to the vertical plate portion 502. The L-shaped pole welding platform 5 can be connected to the vertical extension portion 301 at the same time, and can also be connected to the bottom surface of the pole body 7 close to the pole group 2, and the connection method can be welding. The L-shaped pole welding platform 5 saves the internal space of the housing 1 and reduces the overall weight while meeting the connection requirements.

[0047] Preferably, if Figures 3 to 6 As shown, in the embodiment, the length of the transverse plate portion 501 in the second direction S2 is greater than the length of the vertical extension portion 301 in the second direction S2. Since the pole lug 3 includes the second inclined surface 305 and sufficient space needs to be reserved for other components, the length of the transverse plate portion 501 needs to be greater than the length of the vertical extension portion 301, which is also convenient for subsequent welding.

[0048] Preferably, if Figure 1 and Figure 2 As shown, in an embodiment, the battery cell may further include a side plate 8 and mylar 9, wherein the mylar 9 is disposed on the periphery of the pole group 2, and the side plate 8 is disposed between the housing 1 and the mylar 9. The mylar 9 may cover the periphery of the pole group 2, mainly as an isolation layer, a protective layer, and an electrolyte impregnation layer. The mylar 9 may be a polyester film. The side plate 8 is disposed on the side of the pole group 2 to protect the side of the battery cell.

[0049] Preferably, if Figure 7 and Figure 8 As shown, in the embodiment, the distance between the pole body 7 and the first end 101 of the shell 1 in the third direction S3 is less than the distance between the pole body 7 and the second end 102 of the shell 1 in the third direction S3. The pole body 7 is arranged close to the first end 101 of the shell 1 in the third direction S3. The two ends of the shell 1 in the third direction S3 are the first end 101 and the second end 102, respectively, and the first end 101 and the second end 102 are arranged opposite to each other. The pole body 7 is arranged close to the first end 101, which is convenient for subsequent connection with adjacent cells to form a battery pack.

[0050] Preferably, if Figure 8 As shown, in the embodiment, when welding the pole lug 3 and the pole welding platform 5, the welding mark 10 in the figure is located close to the pole body 7, which is convenient for welding.

[0051] Through the cooperation of the pole group and the shell, the pole ear of the pole group is vertically led out of the battery cell, thereby avoiding the problem of wrinkles and tears of the pole ear in the original structure. At the same time, the pole ear at the end of the pole group is directly connected to the pole welding base of the cover plate assembly, eliminating the end plate in the original structure, reducing the overall number of parts and the number of assembly steps. Due to the reduction in the number of parts, the space inside the shell 1 is also saved, thereby increasing the capacity of the battery cell.

[0052] In addition, according to the second aspect of the present invention, a battery pack is provided, which includes the battery cell described above. Since the battery pack uses the battery cell described above and each battery cell can increase capacity, the overall capacity of the battery pack is increased, thereby increasing the battery life.

[0053] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A battery cell, characterized in that: The battery cell comprises: A shell, wherein at least one end of the shell is provided with a cover plate assembly; A pole group is arranged inside the shell, at least one end of the pole group is provided with a pole ear, and the pole ear is connected to the cover plate assembly; The pole lug includes a vertical extension portion extending from the end surface of the pole group toward the cover plate assembly, and the cover plate assembly includes a pole welding platform extending from the end surface of the cover plate assembly toward the pole group, and the vertical extension portion is connected to the pole welding platform.

2. The battery cell according to claim 1, characterized in that: The pole lug further includes a connecting platform portion, which includes a first platform and a second platform facing away from each other, the first platform is connected to the end surface of the pole group, and the second platform is provided with the vertical extension portion.

3. The battery cell according to claim 2, characterized in that: The vertical extension portion divides the second table surface into a first inclined surface and a second inclined surface, an end of the pole welding platform is close to the second inclined surface, and the pole welding platform is welded to the vertical extension portion.

4. The battery cell according to claim 3, characterized in that: The length of the second inclined surface in the first direction is smaller than the length of the first inclined surface in the first direction.

5. The battery cell according to claim 1, characterized in that: The cover plate assembly further comprises a plate body and a pole body, wherein the pole body penetrates the plate body, and the pole body is connected to the pole ear through the pole welding platform.

6. The battery cell according to claim 5, characterized in that: The pole welding platform is formed as an L-shaped member, and includes a horizontal plate portion connected to the vertical extension portion and a vertical plate portion connected to the pole body, wherein the horizontal plate portion is perpendicular to the vertical plate portion.

7. The battery cell according to claim 6, characterized in that: The length of the transverse plate portion in the second direction is greater than the length of the vertical extension portion in the second direction.

8. The battery cell according to claim 1, characterized in that: The battery core further includes a side plate and mylar, wherein the mylar is arranged on the outer periphery of the electrode group, and the side plate is arranged between the shell and the mylar.

9. The battery cell according to claim 5, characterized in that: The distance between the pole body and the first end of the shell in the third direction is smaller than the distance between the pole body and the second end of the shell in the third direction.

10. A battery pack, characterized in that: The battery pack comprises the battery cell according to any one of claims 1 to 9.

Images