Battery cell

Abstract

The utility model provides a battery cell and relates to the technical field of batteries. The battery cell comprises a first supporting plate, a fixing assembly and a plurality of pole groups, the pole groups are arranged in the length direction of the pole groups, each pole group comprises a positive tab and a negative tab, and the positive tabs and the negative tabs are located on the two sides of the pole groups in the length direction respectively; first supporting plates are arranged on the two opposite surfaces of every two adjacent pole groups, the positive tab in one pole group of every two adjacent pole groups is connected with the negative tab in the other pole group, and every two adjacent first supporting plates are attached to the two sides, in the length direction, of the fixing assembly respectively. Every two adjacent pole groups can be connected through the corresponding fixing assembly and the corresponding first supporting plate, and then the multiple pole groups are connected. Therefore, a plurality of pole groups with relatively small lengths are used for replacing a pole group with relatively large length, and the length of a single pole group is relatively small, so that the risks of wrinkling, deformation, layer channeling and breakage of the pole groups are reduced, and the reject ratio of the battery cells is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and in particular to an electric core. Background Art

[0002] With the increasing maturity of lithium-ion battery technology, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields. As an important part of the electric core, the electrode assembly directly affects the quality of the electric core.

[0003] With the optimization of the electric core structure, electric cores with larger lengths have emerged. However, as the length of the electric core increases, the length of the electrode assembly of the electric core also increases, which increases the risks of the electrode assembly wrinkling, deforming, delaminating, and breaking, and the defective rate of the electric core rises. Utility Model Content

[0004] In view of this, the present application provides an electric core to solve the problem that as the length of the electric core increases, the length of the electrode assembly increases, which increases the risks of the electrode assembly wrinkling, deforming, delaminating, and breaking, and the defective rate of the electric core rises.

[0005] The present application provides an electric core, which includes a first support plate, a fixing component, and a plurality of electrode assemblies. The plurality of electrode assemblies are arranged along the length direction of the electrode assembly. The electrode assembly includes a positive electrode tab and a negative electrode tab, and the positive electrode tab and the negative electrode tab are respectively located on both sides of the electrode assembly in the length direction;

[0006] The first support plates are arranged on two opposite surfaces of two adjacent electrode assemblies. The positive electrode tab in one of the two adjacent electrode assemblies is connected to the negative electrode tab in the other electrode assembly. The two adjacent first support plates are respectively attached to both sides of the fixing component in the length direction.

[0007] Preferably, the electric core includes a second support plate, a positive electrode cover plate, and a negative electrode cover plate. The second support plate is connected to the electrode assembly close to the negative electrode cover plate. The negative electrode tab in the electrode assembly close to the negative electrode cover plate passes through the second support plate and is connected to the negative electrode cover plate. The positive electrode tab in the electrode assembly close to the positive electrode cover plate is connected to the positive electrode cover plate.

[0008] Preferably, the fixing component includes two fixing members. The fixing member includes a fitting plane and a receiving groove. The fitting plane is perpendicular to the thickness direction of the electrode assembly. The receiving groove is recessed from the fitting plane into the interior of the fixing member, and both ends of the receiving groove are open in the length direction;

[0009] The two fitting planes are fitted together, and the two receiving grooves enclose a receiving space. The positive electrode tabs in one of the adjacent pole groups and the negative electrode tabs in the other adjacent pole group extend into the receiving space.

[0010] Preferably, a part of the positive electrode tab in one of the adjacent pole groups and a part of the negative electrode tab in the other adjacent pole group are stacked along the thickness direction.

[0011] Preferably, the battery cell further includes two side plates which are spaced apart along the width direction of the pole group. Any one of the pole groups is attached to the two side plates respectively on the two sides facing away from each other in the width direction.

[0012] Preferably, the battery cell further includes a housing and an insulating film. The insulating film covers the plurality of pole groups and the two side plates, the housing covers the insulating film, and the positive electrode cover plate and the negative electrode cover plate are respectively arranged at both ends of the housing in the length direction.

[0013] Preferably, the battery cell includes two first explosion-proof valves. The positive electrode cover plate includes a first mounting opening, the negative electrode cover plate includes a second mounting opening, and the two first explosion-proof valves are respectively arranged on the first mounting opening and the second mounting opening.

[0014] Preferably, the battery cell further includes a second explosion-proof valve. The housing includes two first plates and two second plates. The two first plates are both perpendicular to the thickness direction, and the two second plates are both perpendicular to the width direction. Each of the first plates is connected to the two second plates respectively at both ends in the width direction.

[0015] A third mounting opening is formed in one of the second plates. An end portion of one of the fixing components faces the third mounting opening, and the second explosion-proof valve is arranged on the third mounting opening.

[0016] Preferably, the thickness of the first support plate is greater than 0.3 mm and less than 1 mm;

[0017] And / or, the thickness of the second support plate is greater than 0.3 mm and less than 1 mm.

[0018] Preferably, the thickness of the side plate is greater than 0.3 mm and less than 0.8 mm.

[0019] In the battery cell of the present application, the battery cell includes a first support plate, a fixing component, and a plurality of electrode groups. The plurality of electrode groups are arranged along the length direction of the electrode group. The electrode group includes a positive electrode tab and a negative electrode tab, and the positive electrode tab and the negative electrode tab are respectively located on both sides of the electrode group in the length direction. First support plates are provided on both surfaces of two adjacent electrode groups facing each other. The positive electrode tab in one of the two adjacent electrode groups is connected to the negative electrode tab in the other electrode group, and the two adjacent first support plates are respectively attached to both sides of the fixing component in the length direction. The fixing component and the first support plate can connect two adjacent electrode groups, and further connect the plurality of electrode groups. In this way, by replacing one electrode group with a large length with a plurality of electrode groups with a small length, the length of a single electrode group is small, reducing the risk of the electrode group wrinkling, deforming, delaminating, and breaking, thereby reducing the defective rate of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0021] Figure 1 Schematic perspective view of the battery cell showing the embodiments of the present utility model;

[0022] Figure 2 Exploded view of the battery cell showing the embodiments of the present utility model;

[0023] Figure 3 Schematic plan view of the battery cell showing the embodiments of the present utility model;

[0024] Figure 4 Showing Figure 3 The cross-sectional view obtained by cutting the battery cell in along A - A';

[0025] Figure 5 Showing Figure 4 The enlarged view of part B in ;

[0026] Figure 6 Schematic diagram showing the gas flow direction inside the housing during thermal runaway;

[0027] Figure 7 Schematic diagram showing the structure of the second support plate;

[0028] Figure 8 Exploded view showing the fixing component;

[0029] Figure 9 Schematic plan view showing the fixing component.

[0030] Icon: 1 - electrode group; 11 - positive tab; 12 - negative tab; 2 - first support plate; 21 - first through - hole; 3 - second support plate; 31 - second through - hole; 4 - fixing component; 41 - fixing piece; 411 - fitting plane; 412 - receiving groove; 413 - first plane; 414 - second plane; 42 - receiving space; 51 - positive cover plate; 52 - negative cover plate; 521 - second mounting opening; 61 - first explosion - proof valve; 62 - second explosion - proof valve; 7 - side plate; 8 - housing; 81 - first plate; 82 - second plate; 83 - third mounting opening; 9 - insulating film; L1 - length direction; L2 - width direction; L3 - thickness direction. Detailed implementation manners

[0031] The following detailed implementation manners are provided to help readers obtain a comprehensive understanding of the methods, devices, and / or systems described herein. However, after understanding the disclosure of this application, various changes, modifications, and equivalents of the methods, devices, and / or systems described herein will be obvious. For example, the order of operations described herein is merely exemplary and is not limited to the order set forth herein. Rather, changes that will be obvious after understanding the disclosure of this application can be made, except for operations that must occur in a specific order. In addition, descriptions of features known in the art may be omitted for the sake of clarity and conciseness.

[0032] The features described herein can be implemented in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein are provided only to illustrate some of the many possible ways of implementing the methods, devices, and / or systems described herein that will be obvious after understanding the disclosure of this application.

[0033] Throughout the specification, when an element (such as, a layer, a region, or a substrate) is described as "on" another element, "connected to" another element, "bonded to" another element, "above" another element, or "covering" another element, it can be directly "on" another element, "connected to" another element, "bonded to" another element, "above" another element, or "covering" another element, or there can be one or more other elements between them. In contrast, when an element is described as "directly on" another element, "directly connected to" another element, "directly bonded to" another element, "directly above" another element, or "directly covering" another element, there can be no other elements between them.

[0034] As used herein, the term "and / or" includes any one of the listed related items and any combination of any two or more of them.

[0035] Although terms such as "first", "second", and "third" may be used herein to describe various components, elements, regions, layers, or sections, these components, elements, regions, layers, or sections are not limited by these terms. Rather, these terms are only used to distinguish one component, element, region, layer, or section from another. Thus, a first component, element, region, layer, or section described herein could also be termed a second component, element, region, layer, or section without departing from the teachings of the examples.

[0036] For ease of description, spatial relationship terms such as "above", "upper", "below", and "lower" may be used herein to describe the relationship of one element to another as shown in the figures. Such spatial relationship terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, an element described as "above" or "upper" relative to another element will then be "below" or "lower" relative to the other element. Thus, the term "above" includes both the orientation of "above" and "below" depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or at other orientations), and the spatial relationship terms used herein will be interpreted accordingly.

[0037] The terms used herein are for the purpose of describing various examples only and are not intended to limit the disclosure. Unless the context clearly dictates otherwise, the singular forms are also intended to include the plural forms. The terms "comprises", "comprising", and "having" list the stated features, quantities, operations, components, elements, and / or combinations thereof that exist, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0038] Due to manufacturing techniques and / or tolerances, variations in the shapes shown in the figures may occur. Thus, the examples described herein are not limited to the specific shapes shown in the figures, but include changes in shape that occur during manufacturing.

[0039] 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.

[0040] The following will be combined with Figures 1 to 9 to describe the battery cell of the present application. In Figures 1 to 9 the length direction L1, width direction L2, and thickness direction L3 of the electrode group are perpendicular to each other in pairs.

[0041] As shown Figures 2 to 6 in the figure, the battery cell includes a first support plate 2, a fixing component 4 and a plurality of electrode groups 1. The plurality of electrode groups 1 are arranged along the length direction L1. The electrode group 1 includes a positive electrode tab 11 and a negative electrode tab 12. The positive electrode tab 11 and the negative electrode tab 12 are respectively located on both sides of the electrode group 1 in the length direction L1. First support plates 2 are provided on two opposite surfaces of two adjacent electrode groups 1. The positive electrode tab 11 in one electrode group 1 and the negative electrode tab 12 in the other adjacent electrode group 1 are connected. The two adjacent first support plates 2 are respectively attached to both sides of the fixing component 4 in the length direction L1. The fixing component 4 and the first support plate 2 can connect two adjacent electrode groups 1, and further connect the plurality of electrode groups 1. In this way, by using a plurality of electrode groups 1 with smaller lengths to replace one electrode group 1 with a larger length, the length of a single electrode group 1 is smaller, reducing the risks of wrinkles, deformation, layer displacement and fracture of the electrode group 1, thereby reducing the defect rate of the battery cell.

[0042] As shown Figure 5 in the figure, a first through hole 21 is formed in the first support plate 2, so that the positive electrode tab 11 or the negative electrode tab 12 can pass through the first through hole 21, facilitating the connection between the positive electrode tab 11 and the negative electrode tab 12. The positive electrode tabs 11 and the negative electrode tabs 12 between the electrode groups 1 are directly welded without the need to additionally provide structural components for connection, reducing the internal resistance of the battery cell and the manufacturing cost of the battery cell at the same time.

[0043] In an embodiment of the present application, as shown Figure 5 in Figure 8 and Figure 9 the figure, the fixing component 4 includes two fixing members 41. The fixing member 41 includes a fitting plane 411 and a receiving groove 412. The fitting plane 411 is perpendicular to the thickness direction L3. The receiving groove 412 is recessed from the fitting plane 411 into the interior of the fixing member 41. The two ends of the receiving groove 412 are open in the length direction L1. The two fitting planes 411 are attached, and the two receiving grooves 412 enclose a receiving space 42. The two ends of the receiving space 42 are open in the length direction L1, so that the positive electrode tab 11 in one of the two adjacent electrode groups 1 and the negative electrode tab 12 in the other electrode group 1 can extend into the receiving space 42, and the positive electrode tab 11 and the negative electrode tab 12 are welded. The welding position of the positive electrode tab 11 and the negative electrode tab 12 is located in the receiving space 42. In this way, the two fixing components 4 can protect the connection position of the positive electrode tab 11 and the negative electrode tab 12, avoiding damage to the connection position of the positive electrode tab 11 and the negative electrode tab 12 due to impact.

[0044] Preferably, the positive electrode tab 11 and the negative electrode tab 12 are horizontally welded, so that a part of the positive electrode tab 11 in one of the adjacent two electrode groups 1 and a part of the negative electrode tab 12 in the other electrode group 1 are stacked along the thickness direction L3 of the electrode group 1. In this way, the space occupied by the positive electrode tab 11 and the negative electrode tab 12 in the length direction L1 can be reduced, thereby increasing the space that the electrode group 1 in the housing 8 can occupy, and thus increasing the capacity density of the battery cell.

[0045] In addition, the fixing member 41 includes a first plane 413 and a second plane 414 that face away from each other in the length direction L1. The two first planes 413 of the two fixing members 41 are attached to the same first support plate 2, and the two second planes 414 of the two fixing members 41 are attached to another first support plate 2. The fixing assembly 4 is assembled by two fixing members 41, which enables the two fixing members 41 to be installed after the positive electrode tab 11 and the negative electrode tab 12 are welded, improving the convenience of welding the positive electrode tab 11 and the negative electrode tab 12.

[0046] In the embodiment of the present application, as Figure 2 and Figure 7 shown, the battery cell includes a second support plate 3, a positive electrode cover plate 51, and a negative electrode cover plate 52. The positive electrode tab 11 in the electrode group 1 close to the positive electrode cover plate 51 is connected to the positive electrode cover plate 51. The second support plate 3 is connected to the electrode group 1 close to the negative electrode cover plate 52. A second through hole 31 is formed in the second support plate 3. The negative electrode tab 12 of the electrode group 1 close to the negative electrode cover plate 52 passes through the second through hole 31 and is connected to the negative electrode cover plate 52. When inserting the electrode group 1 into the housing, the second support plate 3 can be pushed to insert multiple electrode groups 1 into the housing 8, ensuring balanced thrust when the electrode group 1 is inserted into the housing. Optionally, the first support plate 2 and the second support plate 3 can be fixed to the electrode group 1 by bonding, hot melting, etc.

[0047] Optionally, the thickness of the first support plate 2 is greater than 0.3 mm and less than 1 mm; for example, the thickness of the first support plate 2 can be 0.35 mm, 0.4 mm, 0.5 mm, 0.7 mm, 0.9 mm, or 0.95 mm, etc.; the thickness of the second support plate 3 is greater than 0.3 mm and less than 1 mm. For example, the thickness of the second support plate 3 can be 0.35 mm, 0.45 mm, 0.55 mm, 0.6 mm, 0.8 mm, or 0.95 mm, etc. By setting the first support plate 2 and the second support plate 3 to the above thicknesses, while ensuring that the first support plate 2 and the second support plate 3 have sufficient strength, the space occupied by the first support plate 2 and the second support plate 3 can be reduced, so that the space that the electrode group 1 can occupy is increased.

[0048] Preferably, the thickness of the first support plate 2 is equal to the thickness of the second support plate 3.

[0049] Further, the battery cell further includes two side plates 7. The two side plates 7 are spaced apart along the width direction L2 of the electrode group 1. Each side of the electrode group 1 facing away from each other in the width direction L2 is respectively attached to the two side plates 7. That is to say, the two side plates 7 can protect both sides of the whole formed by multiple electrode groups 1 in the width direction L2, reducing the number of side plates 7 and simplifying the process of assembling the battery cell.

[0050] Preferably, the thickness of the side plate 7 is greater than 0.3 mm and less than 0.8 mm. For example, the thickness of the side plate 7 can be 0.35 mm, 0.4 mm, 0.5 mm, 0.65 mm or 0.7 mm, etc. By setting the side plate 7 to the above thickness, while ensuring that the side plate 7 has sufficient strength, the space occupied by the side plate 7 can be reduced, so that the space that the electrode group 1 can occupy is increased.

[0051] In addition, the battery cell further includes a housing 8 and an insulating film 9. The insulating film 9 covers multiple electrode groups 1 and two side plates 7, and the housing 8 covers the insulating film 9. The positive electrode cover plate 51 and the negative electrode cover plate 52 are respectively arranged at both ends of the housing 8 in the length direction L1.

[0052] In the embodiments of the present application, as Figure 1 、 Figure 2 、 Figure 3 and Figure 6 shown, the battery cell includes two first explosion-proof valves 61. The positive electrode cover plate 51 includes a first mounting opening, and the negative electrode cover plate 52 includes a second mounting opening 521. The two first explosion-proof valves 61 are respectively arranged on the first mounting opening and the second mounting opening 521. When thermal runaway occurs, gas can be discharged through the first explosion-proof valves 61.

[0053] Further, the battery cell further includes a second explosion-proof valve 62. The housing 8 includes two first plates 81 and two second plates 82. Both of the two first plates 81 are perpendicular to the thickness direction L3, and both of the two second plates 82 are perpendicular to the width direction L2. Each end of any one of the first plates 81 in the width direction L2 is respectively connected to the two second plates 82. A third mounting opening 83 is formed on one of the second plates. The fixing component 4 faces the third mounting opening 83 at the end in the width direction L2. The second explosion-proof valve 62 is arranged on the third mounting opening 83. An opening is provided at the position of the insulating film 9 corresponding to the second explosion-proof valve 62, which can facilitate the discharge of gas during thermal runaway. When thermal runaway occurs, as Figure 6 shown, the gas in the middle of the battery cell can be quickly discharged through the second explosion-proof valve 62, and the gas on both sides can be quickly discharged through the two first explosion-proof valves 61. Through the cooperation of the two first explosion-proof valves 61 and one second explosion-proof valve 62, the exhaust efficiency can be improved, the airway travel can be shortened, and thus the safety of the battery cell can be improved.

[0054] Optionally, the number of the pole groups 1 in the battery cell can be selected according to requirements, such as two, three, four or more. Taking the number of the pole groups 1 being two as an example, at this time, the battery cell includes two first support plates 2 and a fixing component 4. The two first support plates 2 are respectively arranged on two opposite surfaces of the two pole groups 1, the fixing component 4 is arranged between the two first support plates 2 and is in contact with the two first support plates 2, and the position of the second explosion-proof valve 62 corresponds to one end of the fixing component 4 in the thickness direction L3.

[0055] The battery cell of the present application replaces one pole group 1 with a relatively large length with multiple pole groups 1 with relatively small lengths. The length of a single pole group 1 is relatively small, reducing the risks of the pole group 1 wrinkling, deforming, layer shifting, and breaking, thereby reducing the defective rate of the battery cell.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery cell, characterized in that, The battery cell includes a first support plate, a fixing component, and a plurality of electrode groups. The plurality of electrode groups are arranged along the length direction of the electrode groups. The electrode group includes a positive electrode tab and a negative electrode tab. The positive electrode tab and the negative electrode tab are respectively located on two sides of the electrode group in the length direction. The first support plates are arranged on two opposite surfaces of two adjacent electrode groups. The positive electrode tab in one of the two adjacent electrode groups is connected to the negative electrode tab in the other electrode group. The two adjacent first support plates are respectively attached to two sides of the fixing component in the length direction.

2. The battery cell according to claim 1, wherein, The battery cell includes a second support plate, a positive electrode cover plate, and a negative electrode cover plate. The second support plate is connected to the electrode group close to the negative electrode cover plate. The negative electrode tab in the electrode group close to the negative electrode cover plate passes through the second support plate and is connected to the negative electrode cover plate. The positive electrode tab in the electrode group close to the positive electrode cover plate is connected to the positive electrode cover plate.

3. The cell according to claim 2, wherein The fixing component includes two fixing members. The fixing member includes a fitting plane and a receiving groove. The fitting plane is perpendicular to the thickness direction of the electrode group. The receiving groove is recessed from the fitting plane into the interior of the fixing member. The two ends of the receiving groove are open in the length direction. The two fitting planes are attached to each other. The two receiving grooves enclose a receiving space. The positive electrode tab in one of the two adjacent electrode groups and the negative electrode tab in the other electrode group extend into the receiving space.

4. The cell according to claim 3, wherein A part of the positive electrode tab in one of the two adjacent electrode groups and a part of the negative electrode tab in the other electrode group are stacked along the thickness direction.

5. The battery cell according to claim 3, characterized in that The battery cell further includes two side plates. The two side plates are arranged at intervals along the width direction of the electrode group. Both sides of any electrode group facing away from each other in the width direction are respectively attached to the two side plates.

6. The battery cell according to claim 5, wherein, The battery cell further includes a housing and an insulating film. The insulating film covers the plurality of electrode groups and the two side plates. The housing covers the insulating film. The positive electrode cover plate and the negative electrode cover plate are respectively arranged at two ends of the housing in the length direction.

7. The battery cell according to claim 2, wherein, The battery cell includes two first explosion-proof valves. The positive electrode cover plate includes a first mounting opening. The negative electrode cover plate includes a second mounting opening. The two first explosion-proof valves are respectively arranged on the first mounting opening and the second mounting opening.

8. The cell according to claim 6, wherein The battery cell further includes a second explosion-proof valve. The housing includes two first plates and two second plates. Both of the two first plates are perpendicular to the thickness direction. Both of the two second plates are perpendicular to the width direction. Both ends of any first plate in the width direction are respectively connected to the two second plates. A third mounting opening is formed in one of the second plates. An end of one of the fixing components in the width direction faces the third mounting opening. The second explosion-proof valve is arranged on the third mounting opening.

9. The battery cell according to claim 2, wherein The thickness of the first support plate is greater than 0.3 mm and less than 1 mm. And / or, the thickness of the second support plate is greater than 0.3 mm and less than 1 mm.

10. The battery cell according to claim 5, wherein, The thickness of the side plate is greater than 0.3 mm and less than 0.8 mm.

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