CN220585450U

CN220585450U - Single battery and preparation device thereof

Info

Publication number: CN220585450U
Application number: CN202322215026.5U
Authority: CN
Inventors: 悦彦排
Original assignee: China Aviation Lithium Battery Co Ltd
Current assignee: China Aviation Lithium Battery Co Ltd
Priority date: 2023-08-17
Filing date: 2023-08-17
Publication date: 2024-03-12
Anticipated expiration: 2033-08-17

Abstract

The utility model relates to the technical field of batteries, and provides a single battery and a preparation device thereof. The single battery includes: the battery cell assembly comprises at least one battery cell, the battery cell comprises a battery cell main body and a tab part led out from the battery cell main body, the tab part is electrically connected with the cover plate assembly, and the tab part comprises a plurality of layers of tab parts; the electrode lugs which are overlapped in multiple layers in the electrode lug parts are folded at the position close to the side wall of one side of the battery core main body along the thickness direction of the battery core main body to form a folded surface; along the direction deviating from the furling surface, the lug in the range of 0% -10% of the lug is in a straightening state in the direction of the battery cell main body pointing to the cover plate component, and the rest lug forms a C-shaped structure which protrudes towards the battery cell main body. The single battery can improve the shape of the lug part between the cover plate component and the battery cell main body by optimizing the structure, and reduce the possibility that the lug part is reversely inserted into the battery cell main body so as to improve the structural performance and the safety performance of the single battery cell.

Description

Single battery and preparation device thereof

Technical Field

The utility model relates to the technical field of batteries, in particular to a single battery and a preparation device thereof.

Background

At present, laminated and wound type battery cell assemblies are commonly adopted in the battery cell manufacturing industry. In order to ensure small battery impedance, the lug parts of the battery cells in the battery cell assembly are designed into multi-lug structures, and the multi-layer lug is connected with the cover plate assembly through a welding process. After the cover plate assembly is connected with the battery cell assembly, the battery cell assembly needs to be bent relative to the cover plate assembly so as to facilitate the assembly of the battery cell assembly into the housing.

It is noted that in the process of bending the tab portion relative to the cover plate assembly, multiple tab shapes are generated under the influence of folding force of multiple layers of tab portions in the tab portion, and an S-shaped shape or a scattered unordered shape is common, however, the tab in the S-shaped shape or the scattered unordered shape is inserted into the battery cell main body, and at this time, the negative tab contacts with the positive tab to cause a short circuit or the positive tab contacts with the negative tab to cause a short circuit.

Disclosure of Invention

The utility model provides a single battery and a preparation device thereof, wherein the single battery can improve the shape of a pole lug part between a cover plate component and a battery core main body by optimizing the structure of the single battery, reduce the possibility that the pole lug part is reversely inserted into the battery core main body, and improve the structural performance and the safety performance of the single battery core.

In order to achieve the above purpose, the present utility model provides the following technical solutions:

according to a first aspect of the present utility model, there is provided a unit cell comprising: the battery cell comprises a battery cell main body and a tab part led out from the battery cell main body, wherein the tab part is electrically connected with the cover plate assembly, and the tab part comprises a plurality of layers of stacked tab parts; the electrode lugs which are overlapped in multiple layers in the electrode lug parts are folded at the position close to the side wall of one side of the battery core main body along the thickness direction of the battery core main body to form a folded surface; along deviating from draw in the face direction, 0% -10% within range's of utmost point ear is in the electric core main part is directional the apron subassembly direction is in the state of flare-out, just the utmost point ear that remains in the utmost point ear forms C shape structure, C shape structure protrusion is to electric core main part.

According to a second aspect of the present utility model, there is provided a device for manufacturing a single battery provided in any of the first aspects, the device having a first station and a second station, the first station being configured to fold and form tab portions in a cell assembly in the single battery, so as to fold and form a folded surface at a position close to a side wall of one side of the cell main body, where the tab portions are stacked in multiple layers; the second station is arranged on one side of the first station, the second station is used for connecting the folded and molded lug parts with the cover plate assembly and bending the lug parts relative to the cover plate assembly, so that the lug parts in the range of 0% -10% in the lug parts are controlled to be in a straightening state along the direction away from the folding surface, the battery cell main body points to the direction of the cover plate assembly, and the rest lug parts in the lug parts are controlled to form a C-shaped structure, and the C-shaped structure protrudes towards the battery cell main body.

It should be noted that, in the single battery provided by the application, the lug of the battery cell is folded to the side wall of one side close to the battery cell main body, and from the folded surface of the lug, the lug in the range of 0% -10% close to the folded surface is in a straightened state, so that the lug is prevented from being redundant between the cover plate component and the battery cell component, and the lug in the residual region can be guaranteed to form a C-shaped structure. Notably, the tab forming the C-shaped structure extends smoothly from the cell body to the cover assembly, so that the tab is prevented from being in an "S" shape and a "random" shape. Accordingly, the single battery provided by the application can reduce the possibility of occurrence of the condition that the lug part is reversely inserted into the main body of the battery cell and short circuit is caused, and even avoid occurrence of the phenomenon that the lug part is reversely inserted into the main body of the battery cell, so that the structural performance and the safety performance of the single battery are improved.

Drawings

For a better understanding of the present disclosure, reference may be made to the embodiments illustrated in the following drawings. The components in the drawings are not necessarily to scale and related elements may be omitted in order to emphasize and clearly illustrate the technical features of the present disclosure. In addition, the relevant elements or components may have different arrangements as known in the art. Furthermore, in the drawings, like reference numerals designate identical or similar parts throughout the several views. Wherein:

Fig. 1 is a schematic view of a part of a structure of a single battery according to an embodiment of the present disclosure;

fig. 2, 3, and 4 to 5 are schematic views of structural changes of the single battery in fig. 1 during preparation;

fig. 6 is a flowchart of a method for preparing a single battery according to an embodiment of the present application;

fig. 7 is a schematic structural diagram of a single battery provided in an embodiment of the present application when being unfolded;

fig. 8 is a schematic view of a part of a first station in a device for preparing a single battery according to an embodiment of the present application;

fig. 9 is a second schematic structural diagram of a first station in the apparatus for preparing a single battery according to the embodiment of the present application;

fig. 10 is a third schematic structural diagram of a second station in the apparatus for manufacturing a single battery according to the embodiment of the present application.

The reference numerals are explained as follows:

100. a cover plate assembly; 200. a cell assembly; 210. a battery cell; 211. a cell body; 212. a tab portion; 300. a connecting sheet; 1. a carrier assembly; 11. a first loading table; 12. a second bearing table; 121. a receiving groove; 122. a welding port; 2. a shaping assembly; 21. a welding port; 3. a connection assembly; p, a first bearing surface; q, the second bearing surface.

Detailed Description

The technical solutions in the exemplary embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings in the exemplary embodiments of the present disclosure. The example embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the present disclosure, and it is therefore to be understood that various modifications and changes may be made to the example embodiments without departing from the scope of the present disclosure.

In the description of the present disclosure, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance unless explicitly specified or limited otherwise; the term "plurality" refers to two or more than two; the term "and/or" includes any and all combinations of one or more of the associated listed items. In particular, references to "the/the" object or "an" object are likewise intended to mean one of a possible plurality of such objects.

Unless specified or indicated otherwise, the terms "connected," "fixed," and the like are to be construed broadly and are, for example, capable of being fixedly connected, detachably connected, or integrally connected, electrically connected, or signally connected; "coupled" may be directly coupled or indirectly coupled through intermediaries. The specific meaning of the terms in the present disclosure may be understood by those skilled in the art according to the specific circumstances.

Further, in the description of the present disclosure, it should be understood that the terms "upper", "lower", "inner", "outer", and the like, as described in the example embodiments of the present disclosure, are described with the angles shown in the drawings, and should not be construed as limiting the example embodiments of the present disclosure. It will also be understood that in the context of an element or feature being connected to another element(s) "upper," "lower," or "inner," "outer," it can be directly connected to the other element(s) "upper," "lower," or "inner," "outer," or indirectly connected to the other element(s) "upper," "lower," or "inner," "outer" via intervening elements.

In a first aspect, embodiments of the present application provide a battery cell. Fig. 1 is a schematic diagram of a part of a structure of a single battery according to an embodiment of the present application. As shown in the structure of fig. 1, the unit cell includes: the battery cell assembly 100 and the battery cell assembly 200, wherein the battery cell assembly 200 comprises at least one battery cell 210, the battery cell 210 comprises a battery cell main body 211 and a tab part 212 led out from the battery cell main body 211, the tab part 212 is electrically connected with the battery cell assembly 100, and the tab part 212 comprises a plurality of layers of stacked tab parts; in the thickness direction of the battery cell main body 211, the multi-layer stacked tabs in the tab portion 212 are folded at a position close to one side wall of the battery cell main body 211 to form a folded surface; along the direction away from the furling surface, 0% -10% of the lugs in the lug 212 are in a straightened state in the direction that the battery cell main body 211 points to the cover plate assembly 100, and the rest lugs in the lug 212 form a C-shaped structure, and the C-shaped structure protrudes towards the battery cell main body 211.

It should be appreciated that the "straightened state" may be a fully or approximately vertical state, with the tabs being generally vertical, along the direction of the cell body 211 toward the cover assembly 100; in the C-shaped structure, each pole piece has an arc-shaped state, and there may be a difference in bending angle of each tab.

It should be noted that, in the single battery provided in this embodiment of the present application, the tab portion 212 of the battery cell 210 is folded to a side wall near the battery cell main body 211, and from the folded surface of the tab portion 212, the tab portion 212 is in a straightened state within a range of 0% -10% near the folded surface, so as to avoid redundant excessive tab portion 212 between the cover plate assembly 100 and the battery cell assembly 200, and further ensure that the tab portion 212 forms a C-shaped structure in the remaining region. It should be noted that, the tab forming the C-shaped structure extends from the cell main body 211 to the cover plate assembly 100 smoothly, so that the possibility of the tab 212 in the S-shaped state and the "disordered" state can be reduced, and even the tab 212 is prevented from being inserted into the cell main body 211. Accordingly, the single battery provided by the embodiment of the application can improve the structural performance and the safety performance of the single battery.

It is noted that the cell main body 211 includes a negative electrode sheet, a positive electrode sheet, and a separator, wherein the separator separates the positive electrode sheet and the negative electrode sheet to avoid occurrence of a short circuit. Taking a negative plate as an example, the negative plate comprises a foil and an active substance coated on at least one side of the foil, and an uncoated part of the foil forms a tab. In the wound or stacked battery cell main body 211, a plurality of layers of tabs drawn from the negative electrode sheet form a tab portion 212 having a negative polarity, and similarly, a plurality of layers of tabs drawn from the positive electrode sheet form a tab portion 212 having a positive polarity.

Fig. 2, 3 to 4 are schematic views of structural changes of the single battery in fig. 1 during preparation. Referring to the structure shown in fig. 2-5, in one embodiment, tab portion 212 includes multiple stacked tabs. As shown in fig. 2, the multiple layers of tabs in the tab portion 212 are stacked in sequence along the thickness direction of the battery cell 210, after the multiple layers of tabs are folded, the tab portion 212 forms the form shown in fig. 3, and the folded surface is located at the bottom of the tab portion 212 in fig. 3; after the tab 212 is folded, as indicated by the arrow in fig. 4, the cell main body 211 may be folded along the arrow, so that a portion of the tab is matched between the cover assembly 100 and the cell main body 211 to form a C-shaped structure.

Of course, when forming the C-shaped structure, the tab portion 212 may also be bent relative to the cell main body 211, which is not described herein.

In a preferred embodiment, the tab 212 is in a straightened state within 0% -20% of the tab near the furled surface, so as to better avoid redundancy of the tab 212 between the cover plate assembly 100 and the battery cell assembly 200, and further improve the success rate of forming a C-shaped structure by the tab in the remaining area, so as to improve the structural performance and the safety performance of the single battery.

In one embodiment, with continued reference to the structure shown in fig. 2-5, tab portion 212 leads out of cell body 211 from the middle of cell body 211 to one side wall of cell body 211 in the thickness direction of cell body 211. It should be understood that the thickness direction of the cell body 211 is parallel to the arrangement direction of the two large faces within the cell 210.

In the present embodiment, tab 212 is led out only in a partial region of cell main body 211 in the thickness direction of cell main body 211. Illustratively, tab portion 212 leads from a half of the area of cell body 211, and the tab within tab portion 212 is gathered from the middle of cell 210 toward the side wall, forming a gathered surface near the side wall. Notably, the structure in this embodiment of the present application may facilitate the folding operation of the multiple layers of tabs in the tab portion 212, so as to improve the structural form of the tab portion 212 after folding, and improve the structural performance of the single battery.

In one embodiment, please continue with the structure shown in fig. 1, the cells210 has a thickness D; along the thickness direction of the battery cell 210, the dimension of the root position of the electrode lug part 212, from which the battery cell main body 211 is led out, is D/2; the distance between the cell main body 211 and the cover plate assembly 100 is H; h ² +(D/2) ² ＝P ² The method comprises the steps of carrying out a first treatment on the surface of the The length of the part of the lug forming the C-shaped structure between the battery cell main body 211 and the cover plate assembly 100 is L, and P is less than or equal to L and less than D/2+H.

Tab portion 212 is formed from multiple layers of tabs that are gathered together, each layer having approximately the same length. It should be noted that, in the present embodiment, the length of the portion of the tab between the battery core main body 211 and the cover plate assembly 100 is L, P is less than or equal to L < D/2+H, wherein the tab 212 is led out from approximately half of the battery core main body 211 and is folded toward one side of the battery core main body 211, so that the P value can be calculated by using the pythagorean theorem through D/2 and H, and the value of L is greater than or equal to the value P calculated by the pythagorean theorem, so as to ensure the bending effect of the tab 212.

It should be appreciated that the closer the value of L is to the P tab, the better the folding effect is to ensure the bending effect of the tab 212, and improve the structural performance of the cell. Moreover, since tab portion 212 includes multiple layers of tabs, L is generally less than D/2+H.

If L is greater than P, it will cause excessive redundancy of the tab portion 212 between the cover assembly 100 and the battery cell main body 211, which will easily cause the pole piece in the tab portion 212 to be reversely inserted into the battery cell main body 211, so as to cause short circuit.

In one embodiment, please continue with the structure shown in fig. 1, the distance H between the cell body 211 and the cover assembly 100 is greater than 0 and less than 5mm; the thickness D of the battery cell 210 is 10mm or more ² And less than or equal to 35mm ² . It should be understood that the distance H is a dimension value of the cover assembly 100 after the housing is buckled, i.e. the height of the assembled battery cell after lamination. In the free state (i.e., not assembled), the distance between the cell body 211 and the cover assembly 100 may be greater, about 0mm to about 5mm, where 0mm is excluded and 5mm is excluded.

It should be noted that, according to the values of H and D, the P value may be calculated to correct whether the margin of the tab portion 212 between the cell main body 211 and the cover assembly 100 is sufficient.

In a preferred embodiment, the distance H between the cell body 211 and the cap plate assembly 100 is 2mm or more and 3mm or less.

Fig. 5 is a schematic diagram of a structural variation of the battery cell in fig. 1 during manufacturing, please refer to the structure shown in fig. 5 with continued reference to fig. 1-4, before the battery cell main body 211 is bent relative to the cover assembly 100 into the structure shown in fig. 1, as shown in fig. 5, a large-surface placement direction of the battery cell main body 211 is substantially parallel to the cover assembly 100, and after the tab portion 212 is connected to the cover assembly 100, a portion of the tab portion extends beyond the cover assembly 100. Illustratively, as shown in FIG. 7, tab portions 212 of each cell 210 may be provided 1mm to 2mm beyond the width of the cover body of cover assembly 100.

In one embodiment, pole pieces positioned near the side walls of cell 210 at pole ears 212 form a gathering surface, and the root position of the pole piece forming the gathering surface has a spacing of 0-2 mm from the side wall of cell 210 near it.

It should be noted that, the structure in this embodiment can promote the success rate of bending and forming the C-shaped structure of the tab portion 212, avoid the folded surface from being far away from the side wall of the battery cell 210, and prevent the pole piece from being able to be straightened within the range of 0% -10% in the tab portion 212, and further avoid the transition bending and forming the S-shaped structure of the tab portion 212 during the process of folding the tab portion 212, so that the structural performance of the single battery can be ensured.

In specifically setting the value of the pitch in the present embodiment, the pitch may be set to one of the following values.

0.01mm、0.1mm、0.2mm、0.3mm、0.4mm、0.5mm、0.6mm、0.7mm、0.8mm、0.9mm、1.0mm、1.1mm、1.2mm、1.3mm、1.4mm、1.5mm、1.6mm、1.7mm、1.8mm、1.9mm、2.0mm。

In one embodiment, the fold surface is in the same plane as the side wall of the cell 210 to ensure that when the tab portion 212 is folded, the tab portion 212 forms a C-shaped structure to a greater extent, avoiding the fold surface from being too far from the side wall of the cell 210, resulting in transitional bending of the tab portion 212 and formation of an S-shaped structure during the folding of the tab portion 212.

In one embodiment, with continued reference to the structure shown in fig. 1-5, the cell assembly 200 includes two cells 210, with the two cells 210 stacked in the thickness direction of the cells 210, and the tab 212 within at least one cell 210 has a C-shaped structure.

It should be noted that, when the number of the battery cells 210 in the battery assembly is plural, the energy density of the single battery can be improved to improve the structural performance thereof.

In one embodiment, with continued reference to the configuration shown in fig. 1, the tabs 212 in both cells 210 have a C-shaped configuration, and the C-shaped configuration in one cell 210 is counter to the direction of protrusion of the C-shaped configuration in the other cell 210.

It should be noted that, this structure arrangement can be convenient for the connection operation of two electric cores 210 and the cover plate body, and can be convenient for buckle electric core main body 211 to all form the tab portion 212 of two electric cores 210 into the C-shaped structure.

In one embodiment, the single battery provided in the embodiments of the present application further includes a connection piece 300, and the tab portion 212 is connected to the cover assembly 100 through the connection piece 300, so as to adapt to the situation of multiple battery cells 210, and facilitate the layout of the tab portion 212 inside the housing.

In a specific embodiment, when a plurality of cells 210 are included in a single battery, the tab portion 212 of each cell 210 is connected to the connection piece 300, and the connection piece 300 is connected to the cover assembly 100, or after the tab portions 212 of the same polarity in two cells 210 are connected to each other by using the same connection piece 300, the cover assembly 100 is connected.

In one embodiment, in the single battery provided in the embodiments of the present application, the cover assembly 100 includes a cover body and a pole, the pole is disposed on the cover body, and the pole ear 212 in the battery cell 210 is connected to the pole, so as to connect the external structure and the battery cell 210 through the pole.

It should be noted that, the cover assembly 100 may further include a lower plastic, an upper plastic or other sealing member, wherein the lower plastic is disposed on the side of the cover body facing the battery cell 210, and the pole is exposed on the surface of the lower plastic to connect to the pole ear 212; the upper plastic is disposed on the side of the cover body facing away from the battery cell 210, and the pole is exposed on the surface of the upper plastic. It should be appreciated that the width dimension of the lower plastic is not necessarily the same as the cover body, and that the cover body is referenced when the tab 212 is set to be outside the dimension of the cover assembly 100 when not bent.

It is noted that each cell 210 includes a positive polarity tab 212 and a negative polarity tab 212, and that tabs 212 of the same polarity in both cells 210 may be connected by the same connection tab 300, and the tabs in the cap assembly 100 may be connected by the connection tab 300. In other words, the pole connected to positive polarity tab 212 has positive polarity and the pole connected to negative polarity tab 212 has negative polarity.

In one embodiment, in each cell 210, positive polarity tab portion 212 and negative polarity tab portion 212 exit from the same side of cell body 211 and are spaced apart. It should be appreciated that in this embodiment, tab portions 212 are cut to optimize the spatial layout of tab portions 212 of different polarities within the housing to improve space utilization within the housing and to improve the energy density of the cell.

In a second aspect, an embodiment of the present application further provides a method for preparing a single battery. Fig. 6 is a flowchart of a method for preparing a single battery according to an embodiment of the present application. Referring to the structure shown in fig. 6 in conjunction with fig. 1 to 5, the method for preparing a single cell is used to prepare a single cell according to any of the above-mentioned first aspects. The preparation method comprises the following steps:

step S102: the cover plate assembly 100 is connected with the lug 212 extending from the battery core main body 211 in the battery core 210 in the battery core assembly 200 so as to enable the multi-layer overlapped lugs in the lug 212 to be folded at a position close to the side wall of one side of the battery core main body 211 along the thickness direction of the battery core main body 211 to form a folded surface;

step S104: the tab portions 212 are bent so as to control tabs in a range of 0% -10% of the tab portions 212 to be in a straightened state in a direction of the cell main body 211 pointing to the cover plate assembly 100 along a direction deviating from the folded surface, and the remaining tab portions in the tab portions 212 are controlled to form a C-shaped structure, wherein the C-shaped structure protrudes toward the cell main body 211.

It should be noted that, in the process of preparing the single battery, step S102 needs to be performed first, to fold the tab portion 212 in the battery cell assembly 200, and then to connect the cover assembly 100 with the tab portion 212 extending from the battery cell main body 211; after the tab portion 212 is connected to the cover plate assembly 100, step S104 is performed to bend the tab portion 212, so as to control 0% -10% of the tab portions 212 to be in a straightened state in the direction of the battery cell main body 211 pointing to the cover plate assembly 100 along the direction away from the folded surface, and control the remaining tab portions in the tab portion 212 to form a C-shaped structure, where the C-shaped structure protrudes toward the battery cell main body 211.

It should be noted that, in the single battery prepared by applying the preparation method provided by the embodiment of the present application, the tab portion 212 of the battery cell 210 is folded to a side wall close to the battery cell main body 211, and from the folded surface of the tab portion 212, the tab portion 212 is in a straightened state within a range of 0% -10% close to the folded surface, so as to avoid excessive redundancy of the tab portion 212 between the cover plate assembly 100 and the battery cell assembly 200, and further ensure that the tab portion 212 forms a C-shaped structure in the remaining region. The C-shaped tab is smoothly extended from the cell main body 211 to the cap plate assembly 100, so that the possibility that the tab portion 212 is in an S-shaped state and a random state can be reduced, and even the tab portion 212 is prevented from being inserted into the cell main body 211. Accordingly, the preparation method can improve the structural performance and the safety performance of the single battery.

In one embodiment, before executing step S102, the preparation method provided in the embodiment of the present application further includes:

step S1022: determining a length L of a portion of the multilayer tab of tab portion 212 between cell body 211 and cover assembly 100;

step S1024: the multiple layers of tabs in tab portion 212 are held and folded at a predetermined folding surface as shown in fig. 2 and 3.

It should be appreciated that if the value of L is too large, it will cause the tab portion 212 to be too redundant between the cover assembly 100 and the battery cell main body 211, which is very likely to cause the tab portion 212 to be reversely inserted into the battery cell main body 211, so as to cause short circuit; if the value of L is too small, the length of the tab portion 212 between the cover assembly 100 and the battery cell main body 211 is too short, and when the battery cell main body 211 is bent relative to the cover assembly 100, the bending amount of the tab portion 212 is insufficient, so that the battery cell main body 211 cannot be bent in place, and the tab portion 212 is torn, thereby affecting the structural performance of the battery cell. Therefore, before the battery cell is prepared, the length L of the portion of the tab 212 between the cell main body 211 and the cover plate assembly 100 needs to be determined, so as to ensure the bending effect of the tab 212 and improve the structural performance of the battery cell.

In one embodiment, in step S1022, the method of determining the length L of the portion of the multilayer tab 212 between the cell body 211 and the cap plate assembly 100 comprises:

After the tab portion 212 is bent, the distance between the cell main body 211 and the cover plate assembly 100 is H, the thickness of the cell 210 is D, and H is combined ² +(D/2) ² ＝P ² Calculating a numerical value P;

and determining L according to the preset value that P is less than or equal to L and less than D/2+H.

It should be noted that, in the present embodiment, the length of the portion of the tab between the battery core main body 211 and the cover plate assembly 100 is L, P is less than or equal to L < D/2+H, wherein the tab 212 is led out from approximately half of the battery core main body 211 and is folded toward one side of the battery core main body 211, so that the P value can be calculated by using the pythagorean theorem through D/2 and H, and the value of L is greater than or equal to the value P calculated by the pythagorean theorem, so as to ensure the bending effect of the tab 212.

It should be noted that if L is too much greater than P, it will cause the tab portion 212 to be too much redundant between the cover assembly 100 and the battery cell main body 211, which is very easy to cause the pole piece in the tab portion 212 to be reversely inserted into the battery cell main body 211, so as to cause short circuit.

In one embodiment, the cell assembly 200 includes two cells 210, the two cells 210 are sequentially arranged along the thickness direction of the cells 210, and the tab portion 212 in each cell 210 is connected to the cover assembly 100; before performing step S102 to connect cover assembly 100 with tab portion 212 of cell assembly 200 extending from cell body 211 of cell 210, the method further includes:

The space S between the two cell main bodies 211 is preset such that the space S between the two cell main bodies 211 exceeds the width of the cover plate body in the cover plate assembly 100 by 2mm to 4mm.

It should be noted that, after connecting the battery cell 210 and the cover plate assembly 100 and before bending the tab portion 212, the distance between the two battery cell main bodies 211 needs to be larger than the width of the cover plate assembly 100, so as to prevent the top of the battery cell main body 211 from being damaged by the cover plate assembly 100 during assembly. Accordingly, redundancy of 2 mm-4 mm is set in the embodiment of the application, so that when the lug part 212 is folded, excessive redundant lug parts 212 cannot exist between the battery cell main body 211 and the cover plate assembly 100, the lug part 212 is folded to form a C-shaped structure, the lug part 212 is prevented from being reversely inserted into the battery cell main body 211, and the structural performance of a single battery can be improved.

Exemplary: the width of the cover body is 36mm, and the initial design gives a spacing S of 44mm between the two cells 210 before bending (in the horizontal direction), where S is 8mm more than the width of the cover body. After the single battery prepared by the size is assembled, the redundancy of the lug 212 is too long, and the reverse insertion proportion of the lug in the lug 212 is more than 3%. After the spacing S is changed to 40mm, at this time, S is 4mm more than the width of the cover plate body, and the tab reverse insertion ratio in the tab portion 212 is reduced to about 1%.

In one embodiment, after bending tab portion 212, the C-shaped structures in one cell 210 are counter-oriented to the protruding direction of the C-shaped structures in the other cell 210.

In a third aspect, embodiments of the present application provide a device for manufacturing a single battery. Fig. 8 is a schematic view of a part of a first station in a device for preparing a single battery according to an embodiment of the present application; fig. 9 is a second schematic structural diagram of a first station in the apparatus for preparing a single battery according to the embodiment of the present application; fig. 10 is a third schematic structural diagram of a second station in the apparatus for manufacturing a single battery according to the embodiment of the present application. Referring to the structures shown in fig. 8 to 10 in conjunction with fig. 1 to 7, the apparatus for preparing a single battery according to the embodiment of the present application is used for preparing a single battery according to any of the foregoing first aspect. The preparation device of the single battery is provided with a first station and a second station, wherein the first station is used for folding and forming the lug parts 212 in the battery cell assembly 200 in the single battery so as to fold and form folding surfaces at the positions of the side walls of one side close to the battery cell main body 211 of the multi-layer stacked lug in the lug parts 212; the second station is arranged at one side of the first station, and is used for connecting the folded and molded lug 212 with the cover plate assembly 100 and bending the lug 212 relative to the cover plate assembly 100 so as to control the lug in the range of 0% -10% in the lug 212 to be in a straightening state in the direction of the cell main body 211 pointing to the cover plate assembly 100 along the direction deviating from the folded surface, and controlling the rest lugs in the lug 212 to form a C-shaped structure, wherein the C-shaped structure is convex to the cell main body 211.

Specifically, when the apparatus for manufacturing a single battery provided in the embodiments of the present application is applied, in the first station, the multiple stacked tabs in the tab portion 212 need to be folded at a position close to a side wall of the battery core main body 211 to form a folded surface; afterwards, the cell assembly 200 needs to be moved to a second station, so that the cover plate assembly 100 is connected with the tab portion 212 extending from the cell main body 211, then, the tab portion 212 needs to be bent at the second station, so that the tab within the range of 0% -10% in the tab portion 212 is controlled to be in a straightened state in the direction of the cell main body 211 pointing to the cover plate assembly 100, and the remaining tab in the tab portion 212 is controlled to form a C-shaped structure, and the C-shaped structure is protruded to the cell main body 211.

It should be noted that, in the single battery obtained by applying the preparation apparatus provided by the embodiment of the present application, the tab portion 212 of the battery cell 210 is folded to a side wall close to the battery cell main body 211, and from the folded surface of the tab portion 212, the tab portion 212 is in a straightened state within a range of 0% -10% close to the folded surface, so as to avoid redundant excessive tab portion 212 between the cover plate assembly 100 and the battery cell assembly 200, and further ensure that the tab portion 212 forms a C-shaped structure in the remaining region. The C-shaped tab is smoothly extended from the cell main body 211 to the cap plate assembly 100, so that the possibility that the tab portion 212 is in an S-shaped state and a random state can be reduced, and even the tab portion 212 is prevented from being inserted into the cell main body 211. Accordingly, the preparation method can improve the structural performance and the safety performance of the single battery.

It should be noted that, the preparation device of the single battery provided by the embodiment of the application can realize automatic preparation operation of the single battery, improve preparation efficiency and reduce preparation cost; meanwhile, the device for manufacturing the single battery provided by the embodiment of the application can improve the success rate of forming the C-shaped structure between the cover plate assembly 100 and the battery cell main body 211 by the lug 212 after bending, so that the product yield is improved, and the structural performance and the safety performance of the single battery are improved.

In one embodiment, please continue to refer to the structure shown in fig. 8 and fig. 9, the preparation apparatus provided in the embodiment of the present application includes a carrying component 1 and a shaping component 2, where the carrying component 1 and the shaping component 2 are disposed at a first station, and the first station includes:

the bearing assembly 1 comprises a first bearing table 11 and a second bearing table 12, the second bearing table 12 is positioned on one side of the first bearing table 11, the first bearing table 11 is provided with a first bearing surface P for bearing the battery cell main body 211, the second bearing table 12 is provided with a second bearing surface Q for bearing the lug part 212, and the first bearing surface P and the second bearing surface Q are positioned on the same side of the bearing assembly 1;

the shaping assembly 2 includes a tab shaping pressing plate movably disposed on one side of the second carrying platform 12, where the tab shaping pressing plate is used to form a pressing limiting space with the second carrying surface Q to shape the tab 212.

Referring to the structure shown in fig. 8 and 9, in the embodiment of the present application, before the tab portion 212 is shaped by pressing, the battery cell main body 211 may be disposed on the first bearing surface P of the first bearing table 11, and at the same time, the tab portion 212 of the battery cell 210 is disposed on the second bearing surface Q of the second bearing table 12. As shown in fig. 2, before the multiple tabs of tab 212 are pressed together, a gap exists between the tabs, and the thickness of tab 212 is approximately 1/2 of the thickness of cell 210; as shown in fig. 3, after the lamination and folding, there is no gap between the laminated tabs, and at this time, the thickness of the tab 212 is the physical thickness of the multi-layer tab.

For example, if the tab shaping pressing plate is located at the top of the battery cell 210, as shown in fig. 9, the tab portions 212 are distributed at 1/2 of the lower portion of the battery cell main body 211 before lamination, and after lamination, the tab portions 212 are distributed at the bottom of the battery cell 210 in a concentrated manner; each layer of pole lugs is in a parallel state with each layer of pole pieces in the battery cell main body 211 before lamination, and each layer of pole lugs is concentrated at the bottom of the battery cell 210 and is parallel with the bottom of the battery cell main body 211 after lamination. It should be appreciated that the pole piece in pole ear 212 proximate second bearing surface Q generally forms a furled surface; after bending tab portion 212, the bottom of cell body 211 forms the side wall of cell body 211 with the folded surface in the above configuration.

It is noted that ultrasonic welding may be used to attach tab portion 212 to the bonded tab portion 212, thereby facilitating attachment of tab portion 212 to other structures.

It should be understood that in this embodiment, the first carrying platform 11 and the second carrying platform 12 may be independent structures, for example, the second carrying platform 12 is detachably connected with respect to the first carrying platform 11, or the second carrying platform 12 and the first carrying platform 11 are two structures separately provided, and after assembly, the two structures are fixed in relative positions; alternatively, the first loading table 11 and the second loading table 12 may be provided as a unitary structure.

When the first carrying platform 11 and the second carrying platform 12 are specifically arranged, the height difference between the first carrying surface P and the second carrying surface Q needs to be considered, so as to optimize the folded tab portion 212, and facilitate the formation of a C-shaped structure when the tab in the tab portion 212 is bent.

In one embodiment, please continue to refer to the structure shown in fig. 8 and 9, the second bearing surface Q is provided with a receiving groove 121 for receiving the connecting piece 300, and a space M is provided between the top of the receiving groove 121 and the first bearing surface P, where the space M is between-1 mm and 2mm.

It should be understood that when the size of the space M is 0-2 mm, the top of the accommodating groove 121 exceeds the first bearing surface P; when the distance M is-1 mm to 0, the top of the accommodating groove 121 is located below the first bearing surface P.

It should be noted that, the shape of the accommodating groove 121 is adapted to the shape of the connecting piece 300, so that the connecting piece 300 can be prevented from moving relative to the tab 212 during the welding operation, and thus, the connection position of the connecting piece 300 and the tab 212 can be ensured to be accurate, so as to improve the yield of the welded product.

Illustratively, the thickness of the connecting piece 300 is 0.5mm to 1mm, and the recess depth of the receiving recess 121 may be greater than 1mm. Of course, the depth of the accommodating groove 121 may be smaller than the thickness of the connecting piece 300, which will not be described in detail.

Referring to the structure shown in fig. 8, after the battery cell 210 is placed on the carrier assembly 1, the bottom of the battery cell main body 211 is placed on the first carrier surface P, and since the connecting piece 300 is disposed in the accommodating groove 121, the bottom pole piece of the tab portion 212 is mounted on the connecting piece 300 or the top of the accommodating groove 121. Specifically, when the top of the connecting piece 300 does not exceed the top of the accommodating groove 121 (i.e., the second bearing surface Q), the folded surface of the tab portion 212 is located on the second bearing surface Q; when the top of the connection piece 300 exceeds the groove top of the receiving groove 121, the folded surface of the part of the tab portion 212 corresponding to the connection piece 300 is located on the top surface of the connection piece 300, and the rest is located on the second carrying surface Q. It should be noted that the height difference between the top of the accommodating groove 121 and the second carrying surface Q cannot be too large, so that the folded tab portion 212 cannot effectively form a C-shaped structure in the subsequent bending operation.

It should be noted that, in this embodiment, the connection piece 300 is pre-disposed at the bottom of the folded surface of the tab portion 212, so that multiple layers of tabs in the tab portion 212 are connected with the connection piece 300 after being folded, so as to improve the assembly efficiency between the two, and improve the connection effect between the tab portion 212 and the connection piece 300, so that the tab portion 212 can effectively form a C-shaped structure after being subsequently folded.

It is noted that after connecting tab 300 is connected to tab 212, cell 210 is connected to cover assembly 100 via connecting tab 300. It should be understood that, taking fig. 8 and fig. 9 as an example, when the unit battery includes a plurality of battery cells 210, the tab portions 212 with the same polarity in the plurality of battery cells 210 may be connected through the connecting sheet 300, and then the cover plate assembly 100 is uniformly connected through the connecting sheet 300, so as to reduce the assembly difficulty of the unit battery and improve the assembly efficiency.

For example, when the assembly device of the single battery provided in the embodiment of the application is applied, when the size of the interval M is controlled to be-1 mm-2 mm, the height difference between the bottom of the battery cell main body 211 and the connecting sheet 300 can be adjusted from 5.4mm to 2mm after the battery cell 210 is connected with the connecting sheet 300, and the proportion of the tab portion 212 being reversely inserted into the battery cell main body 211 is reduced from 0.66% to 0.1%.

In one embodiment, please continue to refer to the structure shown in fig. 8 and 9, the tab shaping platen is provided with a welding port 21, and the welding port 21 communicates with the holding-limiting space. Notably, the weld 21 is used to correspond to the overlapping portion of tab portion 212 and tab 300 so that the weld head can extend into from weld interface 21 and weld tab portion 212 and tab 300 disposed under the tab shaping platen.

In a particular embodiment, the size of the weld 21 is smaller than the size of the tab 300.

It should be noted that this configuration allows the tab shaping platen to effectively compress the overlapping portions of tab 300 and tab 212, thereby improving the welding effect.

It is noted that, when the size of the weld 21 is set, it is also possible to set: the welding opening 21 of the lug shaping pressing plate is larger than the welding head so that the welding head stretches into the welding opening 21 to weld.

In one embodiment, a welding port 122 is arranged on the side, facing away from the second bearing surface Q, of the second bearing table 12, and the welding port 122 is communicated with the accommodating groove 121; the holding limiting space includes a receiving groove 121.

It is noted that welding from both sides is required for the overlapping portion of tab 300 and tab 212 to ensure stability of the connection of tab 300 to tab 212. With continued reference to the structure shown in fig. 8 and 9, the welding opening 122 of the second carrying platform 12 is aligned with the welding opening 21 of the tab shaping platen.

When the welding port 122 of the second carrying platform 12 is aligned with the welding port 21 of the tab shaping platen, the welding head of the welding device may extend into the welding port 122 of the second carrying platform 12, and the connecting piece 300 and the tab 212 are welded from below the connecting piece 300; additional welding heads may extend from the welding port 21 of the tab shaping platen and weld tab 212 and tab 300 from above tab 212.

In one embodiment, a welding assembly is also included that is capable of extending from weld interface 21 and/or weld port 122 into the hold-down spacing to weld tab portion 212 to connection tab 300. It should be appreciated that the weld assembly includes a weld head that may extend into weld 21 and/or weld 122 to weld tab 212 and bond pad 300.

In one embodiment, the tab shaping platen is magnetically affixed to the second carrier 12. It will be appreciated that the tab shaping platen is fixed relative to the second carrier 12 by magnetic attraction and the tab 212 is shaped and retracted by the magnetic attraction.

It should be noted that, the manner of magnetic attraction fixation between the tab shaping pressing plate and the second carrying platform 12 is simple and easy to implement, and can improve shaping efficiency of the tab 212, so as to improve preparation efficiency of the single battery and reduce preparation cost.

Specifically, before ultrasonic welding, the tab portion 212 is pressed by the tab shaping pressing plate in this embodiment, and the tab portion 212 is shaped by the magnetic attraction between the tab shaping pressing plate and the second carrying table 12.

In a specific embodiment, the tab shaping platen is embedded with a first magnet, and the second carrier 12 is embedded with a second magnet, where the first magnet and the first magnet can be magnetically fixed.

Of course, the tab shaping pressing plate may be further disposed on a driving member, and the tab shaping pressing plate is driven by the driving member to move relative to the second bearing table 12, and the driving member is used for controlling the pressing force of the tab shaping pressing plate relative to the second bearing surface Q, which is not described in detail.

In order to more clearly understand the preparation device of the single battery provided in the embodiment of the present application, a specific operation example of the preparation device is now provided.

1. The tab 300 is placed on the second carrier 12, specifically, the tab 300 is placed in the receiving groove 121, either manually or by an apparatus.

2. The manual or equipment places the cell body 211 on the first carrier 11 and the tab 212 moves with the cell body 211 directly above the tab 300.

3. The manual or equipment tab shaping pressing plate is placed on the bearing assembly 1, and the tab shaping pressing plate and the second bearing table 12 are attracted by means of the attraction force of the magnet to shape the tab 212. Specifically, the shaping press block is located directly above the lug 212, and the magnets are embedded in the lug shaping press plate and the second bearing table 12 at two ends of the lug shaping press plate and the second bearing table 12.

It should be noted that, during the whole row process of the tab portion 212, the cell 210 shaping platen may be further used to press the cell main body 211, so as to shape the cell main body 211, and even improve the shaping effect of the tab shaping platen on the tab portion 212, so as to prevent the cell main body 211 from moving during the shaping process of the tab portion 212.

For example, the shaping platen of the battery cell 210 may be driven by the pressing mechanism to move relative to the second carrying platform 12, and after the pressing mechanism starts the pressing action, the spring above the shaping platen of the battery cell 210 connected by the pressing mechanism is compressed to a fixed deformation, so as to perform a better shaping function on the battery cell main body 211.

When welding tab portion 212 and connecting piece 300, welding may be performed by a welder, where the welding head of the welder extends into weld 21 or weld 122 to perform the welding operation. It should be appreciated that the mobile operation of the welder may be accomplished manually or by equipment.

After the welding is completed, the pressing mechanism is lifted back, the shaping pressing plate of the battery cell 210 is lifted back, the lug shaping pressing plate is taken away manually or by equipment, and the battery cell 210 is taken away manually or by equipment.

In one embodiment, referring to the structure shown in fig. 10, the second station includes a connection assembly 3, the connection assembly 3 is used for connecting the tab portion 212 after the shaping of the first station with the cover plate assembly 100, and the connection assembly 3 is used for bending the tab portion 212 so as to control the tab portion in the range of 0% -10% of the tab portions 212 to be in a straightened state in the direction of the battery cell main body 211 pointing to the cover plate assembly 100 along the direction deviating from the furling surface, and the remaining tab portions in the tab portions 212 are controlled to form a C-shaped structure, wherein the C-shaped structure is convex to the battery cell main body 211.

It should be noted that, when the tab portion 212 of the battery cell 210 is shaped at the first station and welded with the connecting piece 300, the connecting piece 300 is connected with the cover plate assembly 100 by the connecting assembly 3, and the connecting assembly 3 bends the tab portion 212, so as to realize automatic preparation of the single battery, improve the preparation efficiency, and reduce the preparation cost.

It should be noted that, in the process of connecting tab portion 212 and connecting piece 300 by connecting component 3, it is necessary to weld cell 210 and cover plate by using a laser, and then a rubberizing process is performed, and then a core assembling process (i.e. a process of bending tab portion 212 in the above-mentioned scheme) is performed.

For example, as shown in fig. 10, when two electric cells 210 are provided in the battery, the two electric cells 210 need to be turned by 90 ° manually or by means of a device (such as the connection assembly 3 in fig. 10) at the time of the battery cell assembly, so that 2 electric cells 210 are combined together. It is noted that, as shown in fig. 10, the cell main body 211 is bent along the direction indicated by the arrow, so that the tab portion 212 forms a C-shaped structure.

It is noted that after the battery cell main body 211 is sealed in the case, the bending position of the tab portion 212 is not pressed down to be inserted into the half battery cell main body 211, so that the safety performance of the battery can be ensured.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the utility model disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the utility model following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. The specification and example embodiments are to be considered exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It is to be understood that the present disclosure is not limited to the precise arrangements and instrumentalities shown in the drawings, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A single cell, characterized by comprising: the battery cell comprises a battery cell main body and a tab part led out from the battery cell main body, wherein the tab part is electrically connected with the cover plate assembly, and the tab part comprises a plurality of layers of stacked tab parts; the electrode lugs which are overlapped in multiple layers in the electrode lug parts are folded at the position close to the side wall of one side of the battery core main body along the thickness direction of the battery core main body to form a folded surface; along deviating from draw in the face direction, 0% -10% within range's of utmost point ear is in the electric core main part is directional the apron subassembly direction is in the state of flare-out, just the utmost point ear that remains in the utmost point ear forms C shape structure, C shape structure protrusion is to electric core main part.

2. The unit cell according to claim 1, wherein the tab portion leads out of the cell main body from a middle portion of the cell main body to a side wall of the cell main body in a thickness direction of the cell main body.

3. The cell of claim 2, wherein the thickness of the cell is D; the size of the root position of the electrode lug part, which is led out of the battery cell main body, is D/2 along the thickness direction of the battery cell; the distance between the battery cell main body and the cover plate component is H; h ² +(D/2) ² ＝P ² ；

The length of the part of the lug forming the C-shaped structure between the battery cell main body and the cover plate component is L, and P is less than or equal to L and less than D/2+H.

4. The cell of claim 3, wherein a distance H between the cell body and the cap assembly is greater than 0 and less than 5mm; the thickness of the battery core is D, is larger than or equal toAt 10mm ² And less than or equal to 35mm ² 。

5. The unit cell according to any one of claims 2 to 4, wherein a pole piece located at a position of the pole ear portion close to a side wall of the battery cell forms the folded surface, and a root position of the pole piece forming the folded surface has a spacing from the side wall of the battery cell close thereto, the spacing being 0 to 2mm.

6. The cell of claim 5, wherein the biasing surface is coplanar with a sidewall of the cell.

7. The battery cell of any one of claims 1-4, wherein the cell assembly comprises two cells stacked in a thickness direction of the cells, and wherein a tab portion within at least one of the cells has the C-shaped configuration.

8. The cell of claim 7, wherein the tab portions in both of the cells have the C-shaped configuration, and wherein the C-shaped configuration in one of the cells is in opposition to the direction of projection of the C-shaped configuration in the other cell.

9. The cell defined in any one of claims 1-4, further comprising a connection tab, wherein the tab portion connects the cover assembly via the connection tab.

10. The cell of any one of claims 1-4, wherein the tab portion comprises a positive tab portion and a negative tab portion, the positive tab portion and the negative tab portion being drawn from the same side of the cell body and disposed in a spaced apart relationship.

11. A device for preparing a single battery according to any one of claims 1 to 10, wherein the device is provided with a first station and a second station, and the first station is used for gathering and forming lug parts in a battery cell assembly in the single battery so as to gather and form gathering surfaces at positions of the lug parts, which are overlapped in multiple layers, close to one side wall of the battery cell main body; the second station is arranged on one side of the first station, the second station is used for connecting the folded and molded lug parts with the cover plate assembly and bending the lug parts relative to the cover plate assembly, so that the lug parts in the range of 0% -10% in the lug parts are controlled to be in a straightening state along the direction away from the folding surface, the battery cell main body points to the direction of the cover plate assembly, and the rest lug parts in the lug parts are controlled to form a C-shaped structure, and the C-shaped structure protrudes towards the battery cell main body.

12. The apparatus for preparing a single battery according to claim 11, comprising a carrying assembly and a shaping assembly, the carrying assembly and the shaping assembly being disposed at the first station, wherein:

the bearing assembly comprises a first bearing table and a second bearing table, the second bearing table is positioned on one side of the first bearing table, the first bearing table is provided with a first bearing surface for bearing the battery cell main body, the second bearing table is provided with a second bearing surface for bearing the tab part, and the second bearing surface and the first bearing surface are positioned on the same side of the bearing assembly;

the shaping assembly comprises a lug shaping pressing plate, the lug shaping pressing plate is movably arranged on one side of the second bearing table, and the lug shaping pressing plate is used for forming a pressing limiting space with the second bearing surface so as to shape the lug.

13. The device for preparing a single battery according to claim 12, wherein the second bearing surface is provided with a containing groove for containing the connecting sheet, a space is arranged between the groove top of the containing groove and the first bearing surface, and the size of the space is-1 mm-2 mm.

14. The device for manufacturing a single battery according to claim 13, wherein the tab shaping pressing plate is provided with a welding port, and the welding port is communicated with the holding limiting space.

15. The device for preparing a single battery according to claim 14, wherein a welding port is arranged on one side of the second bearing table, which is away from the second bearing surface, and the welding port is communicated with the accommodating groove; the holding limiting space comprises the accommodating groove.

16. The apparatus according to claim 14 or 15, further comprising a welding assembly capable of extending into the holding-down spacing space from the welding port to weld the tab portion and the connecting piece.

17. The apparatus for manufacturing a single battery according to any one of claims 12 to 15, wherein the tab shaping pressing plate is magnetically fixed to the second carrying table.

18. The device for manufacturing a single battery according to claim 17, wherein the tab shaping pressing plate is embedded with a first magnet, the second bearing table is embedded with a second magnet, and the first magnet can be magnetically fixed.

19. The apparatus of any one of claims 12-15, wherein the shaping assembly further comprises a driving member coupled to the tab shaping platen for driving the tab shaping platen to move relative to the second bearing surface.

20. The device for preparing a single battery according to any one of claims 11 to 15, wherein the second station comprises a connecting component for connecting the tab portion shaped by the first station with the cover plate component, and the connecting component is used for bending the tab portion so as to control the tab portion in the range of 0% -10% to be in a straightened state in the direction of the battery core main body pointing to the cover plate component along the direction deviating from the furling surface, and control the remaining tab portion in the tab portion to form a C-shaped structure, and the C-shaped structure is protruded to the battery core main body.