Battery cell

Abstract

The utility model provides a battery cell and relates to the technical field of batteries. The battery cell comprises a fixing assembly and a plurality of pole groups, any pole group comprises a positive tab and a negative tab, the plurality of pole groups are arranged along the length direction of the pole groups, the fixing assembly is arranged between any two adjacent pole groups, and two opposite surfaces of the two adjacent pole groups are attached to the fixing assembly; the fixing assembly comprises an accommodating space, the positive tab in one of two adjacent pole groups and the negative tab in the other pole group extend into the accommodating space, and the positive tab and the negative tab extending into the accommodating space are connected. Every two adjacent pole groups can be connected through the corresponding fixing assembly, 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 particularly 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, with the increase in the length of the electric core, the length of the electrode assembly of the electric core also increases, which increases the risks of wrinkling, deformation, layer displacement, and fracture of the electrode assembly, and raises the defective rate of the electric core. Summary of the Utility Model

[0004] In view of this, the present application provides an electric core to solve the problem that with the increase in the length of the electric core, the increase in the length of the electrode assembly increases the risks of wrinkling, deformation, layer displacement, and fracture of the electrode assembly, and raises the defective rate of the electric core.

[0005] The present application provides an electric core, which includes a fixing component and a plurality of electrode assemblies. Any one of the electrode assemblies includes a positive electrode tab and a negative electrode tab. The plurality of electrode assemblies are arranged along the length direction of the electrode assembly, and the fixing component is arranged between any two adjacent electrode assemblies. Two opposite surfaces of two adjacent electrode assemblies are both attached to the fixing component;

[0006] The fixing component includes an accommodation space. The positive electrode tab in one of the two adjacent electrode assemblies and the negative electrode tab in the other electrode assembly both extend into the accommodation space, and the positive electrode tab and the negative electrode tab extending into the accommodation space are connected.

[0007] Preferably, the fixing component includes two fixing members. Each fixing member includes a fitting plane and a receiving groove. The receiving groove is recessed from the fitting plane into the interior of the fixing member. Both ends of the receiving groove are open in the length direction. The two fitting planes are attached to each other, and the two receiving grooves enclose the accommodation space.

[0008] Preferably, the fixing member further includes a limiting plane. The limiting plane is located at the bottom of the receiving groove. The two limiting planes included in the two fixing members are parallel to each other, and the distance between the two limiting planes is greater than 2 mm and less than 6 mm.

[0009] Preferably, the sum of the thickness of the positive electrode tab and the thickness of the negative electrode tab is a predetermined size, and half of the difference between the distance between the two limiting planes and the predetermined size is greater than 0.5 mm.

[0010] Preferably, the battery cell includes a support plate, a positive electrode cover plate, and a negative electrode cover plate. The 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 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.

[0011] Preferably, the fixing member includes a first plane and a second plane that face away from each other in the length direction. Two first planes in the two fixing members are attached to one electrode group, and two second planes in the two fixing members are attached to the other electrode group.

[0012] Preferably, the battery cell further includes side plates. Two side plates are correspondingly provided for each electrode group. Two surfaces of the electrode group that face away from each other in the width direction are respectively attached to the two side plates.

[0013] Preferably, the battery cell further includes a housing and an insulating film. The insulating film covers the plurality of electrode groups and the 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.

[0014] 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. The two first explosion-proof valves are respectively arranged on the first mounting opening and the second mounting opening.

[0015] Preferably, the battery cell further includes two second explosion-proof valves. The housing is provided with two third mounting openings. The two second explosion-proof valves are arranged on the two third mounting openings.

[0016] In the battery cell of the present application, the battery cell includes a fixing assembly and a plurality of electrode groups. Any electrode group includes a positive electrode tab and a negative electrode tab. The plurality of electrode groups are arranged along the length direction of the electrode group. A fixing assembly is arranged between any two adjacent electrode groups. Two surfaces of two adjacent electrode groups that face each other are respectively attached to the fixing assembly. The fixing assembly includes a receiving space. The positive electrode tab in one electrode group and the negative electrode tab in the other electrode group among two adjacent electrode groups both extend into the receiving space. The positive electrode tab and the negative electrode tab extending into the receiving space are connected. Through the fixing assembly, two adjacent electrode groups can be connected, and further, the plurality of electrode groups can be connected. In this way, by using a plurality of electrode groups with smaller lengths to replace one electrode group with a larger length, the length of a single electrode group is smaller, reducing the risks of the electrode group having wrinkles, deformation, layer displacement, and fracture, thereby reducing the defective rate of the battery cell. Description of the Drawings

[0017] 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 should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other relevant drawings can also be obtained based on these drawings.

[0018] Figure 1 Schematic diagram of the three-dimensional structure of the battery cell showing the embodiments of the present utility model;

[0019] Figure 2 Exploded view of the battery cell showing the embodiments of the present utility model;

[0020] Figure 3 Schematic diagram of the planar structure of the battery cell showing the embodiments of the present utility model;

[0021] Figure 4 Show Figure 3 Cross-sectional view obtained by cutting the battery cell in along A-A';

[0022] Figure 5 Show Figure 3 Cross-sectional view obtained by cutting the battery cell in along B-B';

[0023] Figure 6 Cross-sectional view showing the location of the fixing component of the battery cell;

[0024] Figure 7 Schematic diagram of the structure of the second support plate;

[0025] Figure 8 Exploded view of the fixing component;

[0026] Figure 9 Schematic diagram of the planar structure of the fixing component.

[0027] Icon: 1 - electrode group; 11 - positive electrode tab; 12 - negative electrode tab; 2 - insulating film; 3 - support plate; 31 - first through hole; 4 - fixing component; 41 - fixing piece; 411 - fitting plane; 412 - accommodation groove; 413 - first plane; 414 - second plane; 415 - limiting plane; 42 - accommodation space; 51 - positive electrode cover plate; 52 - negative electrode cover plate; 61 - first explosion-proof valve; 62 - second explosion-proof valve; 7 - side plate; 8 - housing; L1 - length direction; L2 - width direction; L3 - thickness direction. Detailed implementation manners

[0028] The following specific embodiments are provided to assist the reader in obtaining a comprehensive understanding of the methods, apparatuses, and / or systems described herein. However, after understanding the disclosure of this application, various changes, modifications, and equivalents of the methods, apparatuses, and / or systems described herein will be apparent. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein, but rather changes that will be apparent after understanding the disclosure of this application may be made, except for operations that must occur in a specific order. Additionally, descriptions of features known in the art may be omitted for increased clarity and conciseness.

[0029] The features described herein may be implemented in different forms and should not be construed as 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, apparatuses, and / or systems described herein that will be apparent after understanding the disclosure of this application.

[0030] Throughout the specification, when an element (such as a layer, region, or substrate) is described as being "on" another element, "connected to" another element, "coupled to" another element, "above" another element, or "covering" another element, it may be directly "on," "connected to," "coupled to," "above," or "covering" the other element, or there may be one or more other elements intervening therebetween. In contrast, when an element is described as being "directly on" another element, "directly connected to" another element, "directly coupled to" another element, "directly above" another element, or "directly covering" another element, there may be no other elements intervening therebetween.

[0031] 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.

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

[0033] 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 include 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 flipped, 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 orientations 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 in other orientations), and the spatial relationship terms used herein will be interpreted accordingly.

[0034] 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 existence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0035] Due to manufacturing techniques and / or tolerances, variations in the shapes shown in the figures may occur. Accordingly, the examples described herein are not limited to the specific shapes shown in the figures, but include changes in shape 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 this application. Additionally, although the examples described herein have a variety of configurations, other configurations are possible as will be apparent after understanding the disclosure of this application.

[0037] The following will be combined with Figures 1 to 9 to describe the battery cells of this 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.

[0038] As Figures 1 to 6As shown, the battery cell includes a fixing component 4 and a plurality of electrode groups 1. Any one of the electrode groups 1 includes a positive electrode tab 11 and a negative electrode tab 12. The plurality of electrode groups 1 are arranged along the length direction L1 of the electrode group 1. A fixing component 4 is provided between any two adjacent electrode groups 1, and the two opposite surfaces of two adjacent electrode groups 1 are both attached to the fixing component 4. The fixing component 4 includes an accommodation space 42. 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 both extend into the accommodation space 42, and the positive electrode tab 11 and the negative electrode tab 12 extending into the accommodation space 42 are connected. The fixing component 4 can connect two adjacent electrode groups 1, and further connect a 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 risk of the electrode group 1 wrinkling, deforming, delaminating, and breaking, thereby reducing the defective rate of the battery cell.

[0039] In the embodiments of the present application, as Figure 5 , Figure 6 , Figure 8 and Figure 9 shown, 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, and both ends of the receiving groove 412 in the length direction L1 are open. The two fitting planes 411 are attached, and the two receiving grooves 412 enclose the accommodation space 42. Both ends of the accommodation space 42 in the length direction L1 are open, 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 accommodation space 42. The positive electrode tab 11 and the negative electrode tab 12 are welded, and the welding point of the positive electrode tab 11 and the negative electrode tab 12 is located in the accommodation space 42. In this way, the two fixing components 4 can protect the connection part of the positive electrode tab 11 and the negative electrode tab 12, avoiding damage to the connection part of the positive electrode tab 11 and the negative electrode tab 12 due to impact. At the same time, the fixing component 4 is formed by assembling two fixing members 41, which is convenient for installing the two fixing members 41 after welding the positive electrode tab 11 and the negative electrode tab 12.

[0040] As Figure 6 shown, the fixing member 41 includes a first plane 413 and a second plane 414 that are opposite to each other in the length direction L1. The two first planes 413 of the two fixing members 41 are attached to the same electrode group 1, and the two second planes 414 of the two fixing members 41 are attached to another electrode group 1. The fixing component 4 is formed by assembling two fixing members 41, which makes it possible to install the two fixing members 41 after welding the positive electrode tab 11 and the negative electrode tab 12, improving the convenience of welding the positive electrode tab 11 and the negative electrode tab 12.

[0041] As Figure 5 and Figure 8As shown, the fixing member 41 further includes a limiting plane 415 located at the bottom of the receiving groove 412. The two limiting planes 415 included in the two fixing members 41 are parallel, and the distance b between the two limiting planes 415 is greater than 2 mm and less than 6 mm, which makes the limiting space have a sufficiently large size in the thickness direction L3 so that the limiting space can accommodate the positive electrode tab 11 and the negative electrode tab 12.

[0042] In addition, the sum of the thickness of the positive electrode tab 11 and the thickness of the negative electrode tab 12 is a predetermined size a, and half of the difference between the distance b between the two limiting planes 415 and the predetermined size a is greater than 0.5 mm, that is, (b - a) / 2 > 0.5 mm. In this way, it can be ensured that there is a moving distance between the fixing member 41 and the positive electrode tab 11 and the negative electrode tab 12, thereby preventing the fixing member 41 from rubbing against the positive electrode tab 11 and the negative electrode tab 12.

[0043] In the embodiment of the present application, the battery cell further includes side plates 7. Two side plates 7 are correspondingly arranged for each electrode group 1. The two surfaces of the electrode group 1 facing away from each other in the width direction L2 are respectively attached to the two side plates 7. Through the two side plates 7, the two sides of the electrode group 1 in the width direction L2 can be protected.

[0044] Furthermore, the battery cell further includes a housing 8 and an insulating film 2. The insulating film 2 covers a plurality of electrode groups 1 and a plurality of side plates 7, and the housing 8 covers the insulating film 2, thereby realizing insulation between the electrode group 1 and the housing 8.

[0045] In the embodiment of the present application, as Figure 2 、 Figure 3 and Figure 7 shown, the battery cell includes a support plate 3, a positive electrode cover plate 51, and a negative electrode cover plate 52. 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. 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. A first through hole 31 is formed in the support plate 3. The negative electrode tab 12 of the electrode group 1 close to the negative electrode cover plate 52 passes through the first through hole 31 and is connected to the negative electrode cover plate 52. When the electrode group 1 is inserted into the housing, the plurality of electrode groups 1 can be pushed into the housing 8 by pushing the support plate 3, ensuring balanced thrust when the electrode group 1 is inserted into the housing. Optionally, the first support plate 3 and the support plate 3 can be fixed to the electrode group 1 by bonding, hot melting, etc.

[0046] In the embodiment of the present application, as Figure 2 and Figure 4 shown, the battery cell includes two first explosion-proof valves 61. The positive electrode cover plate 51 includes a first installation opening, and the negative electrode cover plate 52 includes a second installation opening. The two first explosion-proof valves 61 are respectively arranged on the first installation opening and the second installation opening. When thermal runaway occurs, gas can be discharged through the two first explosion-proof valves 61.

[0047] Further, the battery cell further includes two second explosion-proof valves 62. Two third mounting openings are formed in the middle of the housing 8, and the two second explosion-proof valves 62 are disposed on the two third mounting openings. Two openings are provided at positions of the insulating film 2 corresponding to the two second explosion-proof valves 62, which can facilitate the discharge of gas during thermal runaway. During thermal runaway, as Figure 4 shown, the gas in the middle of the battery cell can be quickly discharged through the two second explosion-proof valves 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 the two second explosion-proof valves 62, the exhaust efficiency can be improved, the airway travel can be shortened, and thus the safety of the battery cell can be enhanced.

[0048] Preferably, the two second explosion-proof valves 62 are respectively disposed on both sides of the housing 8 in the width direction L2, and the positions of the two second explosion-proof valves 62 correspond to both ends of the same fixing component 4 in the thickness direction L3.

[0049] Optionally, the number of the electrode groups 1 in the battery cell can be selected according to requirements, such as two, three, four or more. Taking the number of the electrode groups 1 being two as an example, at this time, the battery cell includes four side plates 7 and one fixing component 4. The four side plates 7 are divided into two groups, and the two groups of side plates 7 are respectively disposed on the two electrode groups 1. The fixing component 4 is disposed between the two electrode groups 1 and is attached to the two electrode groups 1, and the positions of the two second explosion-proof valves 62 correspond to both ends of the fixing component 4 in the thickness direction L3.

[0050] The battery cell of the present application replaces one electrode group 1 with a larger length with multiple electrode groups 1 with smaller lengths. The length of a single electrode group 1 is smaller, which reduces the risk of the electrode group 1 wrinkling, deforming, delaminating, and breaking, thereby reducing the defective rate of the battery cell.

[0051] 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 it; 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 recorded 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 fixing component and a plurality of pole groups. Any one of the pole groups includes a positive electrode tab and a negative electrode tab. The plurality of pole groups are arranged along the length direction of the pole groups. The fixing component is disposed between any two adjacent pole groups, and two surfaces of two adjacent pole groups facing each other are respectively adhered to the fixing component; The fixing component includes an accommodation space. The positive electrode tab in one of two adjacent pole groups and the negative electrode tab in the other pole group both extend into the accommodation space, and the positive electrode tab and the negative electrode tab extending into the accommodation space are connected.

2. The battery cell according to claim 1, characterized in that, The fixing component includes two fixing members. The fixing member includes a fitting plane and a receiving groove. The receiving groove is recessed from the fitting plane into the interior of the fixing member. Both ends of the receiving groove in the length direction are open, and the two fitting planes are adhered to each other, and the two receiving grooves enclose the accommodation space.

3. The battery cell according to claim 2, characterized in that, The fixing member further includes a limiting plane. The limiting plane is located at the bottom of the receiving groove. The two limiting planes included in the two fixing members are parallel to each other, and the distance between the two limiting planes is greater than 2 mm and less than 6 mm.

4. The battery cell according to claim 3, characterized in that, The sum of the thickness of the positive electrode tab and the thickness of the negative electrode tab is a predetermined dimension, and half of the difference between the distance between the two limiting planes and the predetermined dimension is greater than 0.5 mm.

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

6. The battery cell according to claim 2, wherein The fixing member includes a first plane and a second plane facing away from each other in the length direction. The two first planes in the two fixing members are adhered to one pole group, and the two second planes in the two fixing members are adhered to another pole group.

7. The battery cell according to claim 5, characterized in that, The battery cell further includes side plates. Two side plates are correspondingly arranged for each pole group, and two surfaces of the pole group facing away from each other in the width direction are respectively adhered to the two side plates.

8. The battery cell according to claim 7, characterized in that, The battery cell further includes a housing and an insulating film. The insulating film covers the plurality of pole groups and the side plates, the housing covers the insulating film, and the positive electrode cover plate and the negative electrode cover plate are respectively disposed at two ends of the housing in the length direction.

9. The battery cell according to claim 8, wherein, The battery cell includes two first explosion-proof valves. The positive electrode cover plate includes a first installation opening, the negative electrode cover plate includes a second installation opening, and the two first explosion-proof valves are respectively disposed on the first installation opening and the second installation opening.

10. The battery cell according to claim 8, characterized in that, The battery cell further includes two second explosion-proof valves. The housing is provided with two third installation openings, and the two second explosion-proof valves are disposed on the two third installation openings.

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