Battery cell and battery module

Abstract

The utility model relates to the technical field of lithium batteries, in particular to a battery cell and a battery module. The battery cell comprises a pole group, a pole group protection structure, a pole lug and a cover plate assembly; the pole group protection structure comprises a first protection plate; the first protection plate is arranged at the end part of the pole group and covers the end surface of the pole group; a through hole is formed in the first protection plate; and the tabs led out from the pole group pass through the through holes and are fixed with the cover plate assembly. According to the battery cell and the battery module provided by the invention, the problems that in the process of pressing the cover plate of the existing battery cell into the shell, the end part of the pole group is often crushed by the end plate, so that the diaphragm is broken, or the tab is inversely inserted into the pole group to cause short circuit and the like are solved.

Description

Technical Field

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

[0002] Lithium-ion batteries are currently widely used in various fields such as transportation power supply, electric energy storage power supply, new energy energy storage power supply, aerospace and military industry due to their large capacity, high operating voltage, strong charge retention ability and long cycle life.

[0003] like Figure 4 and Figure 5 As shown in the figure, a bare lithium-ion battery cell is usually composed of a cover plate (with integrated pole, explosion-proof valve, injection hole, etc.), a shell, an end plate (pole ear protection support), an insulating film, a pole group, etc. The insulating film wrapped outside the pole group plays an insulating and protective role.

[0004] In actual production, after the pole tabs are welded to the pole posts on the cover plate, the cover plate needs to be assembled and welded to the shell. However, in the process of pressing the cover plate into the shell, the pole group ends are often crushed by the end plate, causing the diaphragm to rupture, or the pole tabs are inserted into the pole group backwards, causing short circuits, which seriously affect the production yield and the overall safety performance of the battery cell. Utility Model Content

[0005] The purpose of the present application is to provide a battery cell and a battery module, thereby solving the problems that, during the process of pressing the cover plate of the existing battery cell into the shell, the end of the electrode group is often crushed by the end plate, causing the diaphragm to rupture, or the electrode ear is inserted inverted into the electrode group, causing a short circuit.

[0006] According to the first aspect of the present application, a battery cell is provided, which includes a pole group, a pole group protection structure, a pole ear and a cover plate assembly; the pole group protection structure includes a first protective plate; the first protective plate is arranged at the end of the pole group and covers the end surface of the pole group; the first protective plate is provided with a through hole; the pole ear led out from the pole group passes through the through hole and is fixed to the cover plate assembly.

[0007] In any of the above technical solutions, further, the first protection plate includes a main board and a bending portion connected to the periphery of the main board; the main board is fixed to the end surface of the pole group, and the bending portion is fixed to the side surface of the pole group.

[0008] In any of the above technical solutions, further, the main board is a rectangular plate; the main board is fixed to the end surface of the pole group by hot melt, or the main board is fixed to the end surface of the pole group by glue; the bending portion is fixed to the side surface of the pole group by hot melt, or the bending portion is fixed to the side surface of the pole group by glue.

[0009] In any of the above technical solutions, further, the pole group protection structure also includes a second protection plate; the second protection plate is attached to the first protection plate, and the first protection plate and the second protection plate are both insulating plates; the perforation penetrates the first protection plate and the second protection plate at the same time.

[0010] In any of the above technical solutions, further, the second protective plate is fixed to the first protective plate by hot melting, or the second protective plate is fixed to the first protective plate by adhesive bonding.

[0011] In any of the above technical solutions, further, the thickness of the first protective plate is 0.3 mm to 0.5 mm.

[0012] In any of the above technical solutions, further, the thickness of the second protective plate is 0.08mm-0.12mm.

[0013] In any of the above technical solutions, further, the battery cell also includes an insulating film; the insulating film is coated on the electrode group and the electrode group protection structure, and the top opening of the insulating film is fixed to the bottom of the cover plate.

[0014] In any of the above technical solutions, further, the battery cell also includes an end plate and an insulating film; the end plate is arranged on the top of the pole group protection structure and is surrounded by the pole ear; the cover plate assembly is arranged on the top of the end plate, and the cover plate assembly includes a pole, a connecting piece, a top cover sheet, an upper plastic part and a lower plastic part; the pole passes through the lower plastic part, the top cover sheet, the upper plastic part and the connecting piece in sequence; the pole ear led out from the pole group is fixed to the pole; the insulating film is coated on the pole group and the end plate, and the top opening of the insulating film is fixed to the lower plastic part or the end plate.

[0015] According to a second aspect of the present application, a battery module is provided, comprising the battery cell as described above.

[0016] The battery cell of the present application includes a pole group, a pole group protection structure, a pole ear and a cover plate assembly. The pole group protection structure includes a first protection plate; the first protection plate is arranged at the end of the pole group and covers the end surface of the pole group; the first protection plate is provided with a through hole; the pole ear led from the pole group passes through the through hole and is fixed to the cover plate assembly.

[0017] According to the above technical features, the beneficial effects of this application are:

[0018] The battery cell of the present application adds a pole group protection structure, and the first protection plate of the pole group protection structure covers the end face of the pole group. When the cover plate is pressed into the shell, the first protection plate can effectively protect the end face of the pole group, thereby reducing the risk of the pole group being crushed by the cover plate / end plate, and reducing the risk of the pole ear being inserted upside down into the interior of the pole group.

[0019] 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

[0020] 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.

[0021] Figure 1 A schematic diagram showing the overall cross-sectional structure of a battery cell according to an embodiment of the present application;

[0022] Figure 2 A schematic diagram showing the installation of a pole group protection structure according to an embodiment of the present application;

[0023] Figure 3 A schematic diagram showing a pole group protection structure according to an embodiment of the present application;

[0024] Figure 4 A schematic diagram showing the overall structure of a battery cell in the prior art is shown;

[0025] Figure 5 The figure shows a schematic diagram of the overall cross-sectional structure of a battery cell in the prior art.

[0026] Icons: 100-pole group; 200-pole group protection structure; 201-first protection plate; 2011-main board; 2012-bending part; 202-second protection plate; 203-tape; 204-perforation; 300-pole ear; 400-end plate; 500-cover plate assembly; 501-pole column; 502-connector; 503-top cover plate; 504-upper plastic part; 505-lower plastic part; 600-insulating film; 700-shell. DETAILED DESCRIPTION

[0027] 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.

[0028] 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.

[0029] 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.

[0030] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more items.

[0031] 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.

[0032] 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.

[0033] The terms used herein are only used to describe various examples and are not used to limit the present disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms "include", "comprise" and "have" list the stated features, quantities, operations, components, elements and / or their combinations that exist, but do not exclude the existence or addition of one or more other features, quantities, operations, components, elements and / or their combinations.

[0034] 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.

[0035] 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.

[0036] Lithium-ion batteries are currently widely used in various fields such as transportation power supply, electric energy storage power supply, new energy energy storage power supply, aerospace and military industry due to their large capacity, high operating voltage, strong charge retention ability and long cycle life.

[0037] like Figure 4 and Figure 5 As shown, in the prior art, a bare lithium-ion battery cell is usually composed of a cover plate assembly 500 (with integrated pole 501, explosion-proof valve, injection hole, etc.), a shell 700, an end plate 400 (pole ear protection support), an insulating film 600, a pole group 100, etc. The pole group 100 is wrapped with an insulating film 600 to provide insulation protection.

[0038] In actual production, after the pole tab 300 is welded to the pole post 501 on the cover plate, the cover plate assembly 500 needs to be assembled and welded to the housing 700. However, in the process of pressing the cover plate assembly 500 into the housing 700, the end of the pole group 100 is often crushed by the end plate 400, resulting in diaphragm rupture, or the pole tab 300 is inserted into the pole group 100 backwards, resulting in a short circuit, etc., which seriously affects the production yield and the overall safety performance of the battery cell.

[0039] In view of this, the first aspect of the present application provides a battery cell, thereby solving the problems that the ends of the pole groups are often crushed by the end plates during the process of pressing the cover plates of the existing battery cells into the shell, causing the diaphragm to rupture, or the pole ears are invertedly inserted into the pole groups, causing short circuits.

[0040] Refer to the following Figures 1 to 3 The battery cells described in some embodiments of the present application are described in detail.

[0041] like Figure 1 and Figure 2 As shown, the battery cell of the present application includes an electrode group 100, an electrode group protection structure 200, an electrode ear 300 and a cover plate assembly. Figure 3 As shown, the pole group protection structure 200 includes a first protection plate 201; the first protection plate 201 is arranged at the end of the pole group 100 and covers the end surface of the pole group 100; the first protection plate 201 is provided with a through hole 204; the pole ear 300 led out from the pole group 100 passes through the through hole 204 and is fixed to the cover plate assembly.

[0042] The battery cell of the present application adds a pole group protection structure 200, and the first protection plate 201 of the pole group protection structure 200 covers the end surface of the pole group 100. When the cover plate is pressed into the shell, the first protection plate 201 can effectively protect the end surface of the pole group 100, thereby reducing the risk of the pole group 100 being crushed by the cover plate / end plate 400, and reducing the risk of the pole ear 300 being inserted upside down into the interior of the pole group 100.

[0043] In the embodiment of the present application, in order to make the first protective plate 201 cover a wider range and be fixed more firmly. Figure 2 As shown, the first protection plate 201 may include a main plate 2011 and a bending portion 2012 connected to the periphery of the main plate 2011. The main plate 2011 is fixed to the end surface of the electrode group 100, and the bending portion 2012 is fixed to the side surface of the electrode group 100.

[0044] As an example, Figure 2 and Figure 3 As shown, the main board 2011 is a rectangular plate; the main board 2011 is fixed to the end surface of the electrode group 100 by hot melt, or the main board 2011 is fixed to the end surface of the electrode group 100 by adhesive; the bending portion 2012 is fixed to the side of the electrode group 100 by hot melt, or the bending portion 2012 is fixed to the side of the electrode group 100 by adhesive tape 203.

[0045] In the embodiment of the present application, in order to further improve the protection strength of the electrode group protection structure 200, the electrode group 100 is protected from being crushed. Figure 3 As shown, the pole group protection structure 200 may further include a second protection plate 202 ; the second protection plate 202 is attached to the first protection plate 201 , and the through hole 204 penetrates both the first protection plate 201 and the second protection plate 202 .

[0046] like Figure 3As shown, both the first protection plate 201 and the second protection plate 202 can be die-cut insulating parts. The thickness of the first protection plate 201 can be 0.3 mm to 0.5 mm, and the thickness of the second protection plate 202 can be 0.08 mm to 0.12 mm. In addition, the total thickness of the first protection plate 201 and the second protection plate 202 should be about 0.6 mm or more, so that sufficient strength can be provided to protect the electrode group 100 from being crushed.

[0047] In the embodiment of the present application, as an example, the second protection plate 202 is fixed to the first protection plate 201 by hot melting, or the second protection plate 202 is fixed to the first protection plate 201 by adhesive bonding.

[0048] The following will refer to Figure 1 The overall structure of the battery cell of the present application is described in detail.

[0049] like Figure 1 As shown, the battery cell of the present application further includes an end plate 400 and an insulating film 600. The end plate 400 is arranged on the top of the pole group protection structure 200 and is arranged around the pole ear 300; the cover plate assembly 500 is arranged on the top of the end plate 400, and the cover plate assembly 500 includes a pole 501, a connector 502 (for example, a rivet block), a top cover sheet 503, an upper plastic part 504 and a lower plastic part 505; the pole 501 passes through the lower plastic part 505, the top cover sheet 503, the upper plastic part 504 and the connector 502 in sequence; the pole ear 300 led out from the pole group 100 is fixed to the pole 501; the insulating film 600 is coated on the pole group 100, the pole group protection structure 200 and the end plate 400, and the top opening of the insulating film 600 is fixed to the lower plastic part 505.

[0050] In summary, the implementation methods of this application are as follows:

[0051] The pole group protection structure is die-cut - the pole group protection plate is hot-melted / pasted and fixed - the pole group protection structure is inserted through the pole ear - the pole group protection plate is folded and hot-melted / pasted and fixed to the outer surface of the pole group - the pole group is surrounded by an insulating film - the insulating film is hot-melted to the lower plastic part at the bottom of the cover plate, so that the pole group is wrapped with insulating materials as a whole to improve its insulation effect. At the same time, the pole group protection structure can effectively protect the upper end surface of the pole group, reduce the risk of crushing the pole group when the cover plate is inserted into the shell, and reduce the risk of short circuit caused by the pole ear being inserted into the pole group in reverse.

[0052] The following table is the simulation data of this application:

[0053] Statistical example of the damage rate of the cover plate into the shell pole group %

[0054]

[0055] According to a second aspect of the present application, a battery module is provided, comprising the battery cell as described above.

[0056] 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 has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that any technician familiar with this technical field can still modify the technical solutions recorded in the aforementioned embodiments within the technical scope disclosed in the present application, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be covered by the protection scope of the present application.

Claims

1. A battery cell, characterized in that: The battery cell comprises a pole group, a pole group protection structure, a pole ear and a cover plate assembly; The pole group protection structure includes a first protection plate; The first protection plate is disposed at the end of the electrode group and covers the end surface of the electrode group; The first protective plate is provided with a perforation; The pole lugs led out from the pole group pass through the through holes and are fixed to the cover plate assembly.

2. The battery cell according to claim 1, characterized in that: The first protection plate includes a main board and a bending portion connected to the periphery of the main board; The main board is fixed to the end surface of the pole group, and the bent portion is fixed to the side surface of the pole group.

3. The battery cell according to claim 2, characterized in that: The main board is a rectangular plate; The main board and the end surface of the electrode group are fixed by hot melting, or the main board and the end surface of the electrode group are fixed by gluing; The bent portion is fixed to the side surface of the electrode group by heat melting, or the bent portion is fixed to the side surface of the electrode group by adhesive bonding.

4. The battery cell according to claim 1, characterized in that: The pole group protection structure also includes a second protection plate; The second protection plate is attached to the first protection plate, and both the first protection plate and the second protection plate are insulating plates; The through hole penetrates the first protection plate and the second protection plate at the same time.

5. The battery cell according to claim 4, characterized in that: The second protection plate is fixed to the first protection plate by hot melting, or the second protection plate is fixed to the first protection plate by adhesive bonding.

6. The battery cell according to claim 1, characterized in that: The thickness of the first protection plate is 0.3 mm to 0.5 mm.

7. The battery cell according to claim 4, characterized in that: The thickness of the second protection plate is 0.08 mm-0.12 mm.

8. The battery cell according to claim 1, characterized in that: The battery cell also includes an insulating film; The insulating film is coated on the electrode group and the electrode group protection structure, and the top opening of the insulating film is fixed to the bottom of the cover plate.

9. The battery cell according to claim 1, characterized in that: The battery cell also includes an end plate and an insulating film; The end plate is arranged on the top of the pole group protection structure and surrounds the pole ear; The cover plate assembly is arranged on the top of the end plate, and the cover plate assembly includes a pole, a connector, a top cover sheet, an upper plastic part and a lower plastic part; The pole passes through the lower plastic part, the top cover sheet, the upper plastic part and the connecting part in sequence; The pole lugs led out from the pole group are fixed to the poles; The insulating film is coated on the pole group and the end plate, and the top opening of the insulating film is fixed to the lower plastic part or the end plate.

10. A battery module, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 9.

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