CN218548507U - Roll up core and battery - Google Patents

Abstract

The embodiment of the application provides a roll up core and battery, wherein, this roll up core is including rolling up core body, first tie coat and second tie coat, the adhesion force of first tie coat is greater than the adhesion force of second tie coat, the first surface and the second surface of second tie coat all have adhesion force, first tie coat with roll up core body and bond, the first surface of second tie coat with the surface bonding of first tie coat, the second surface of second tie coat is used for rolling up core with the adventitia and bonds. Through set up the different two-layer tie coat of adhesion force between rolling up the core body and rolling up the core adventitia, and the great first tie coat of adhesion force bonds with rolling up the core body, the less second tie coat of adhesion force bonds first tie coat and roll up the core adventitia, compare in the correlation technique with the less second tie coat of adhesion force (like the hot melt adhesive) directly bonding in rolling up the core, can improve the adhesion force between rolling up core and the roll core adventitia, thereby when physical abuse has been reduced, roll up the core and roll up the risk of the relative displacement that the core adventitia takes place, the safety in utilization of battery is improved.

Description

Roll up core and battery

Technical Field

The application relates to the technical field of batteries, in particular to a battery and electronic equipment.

Background

When a lithium battery winding core is packaged, hot melt adhesive is generally required to be adhered between the winding core and an aluminum plastic film so as to fix the relative position of the winding core and the aluminum plastic film. Because the hot melt adhesive is direct to paste with rolling up the core, in the hot melt adhesive melting and solidification process, the stress that the hot melt adhesive produced can all be applied to rolling up the core, and this probably leads to the cracked risk that reaches the core damage of pole piece.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a roll up core, including rolling up core body, first tie coat and second tie coat, the adhesion force of first tie coat is greater than the adhesion force of second tie coat, the first surface of second tie coat bonds and the second surface all has the adhesion force, first tie coat with roll up the core body and bond, the first surface of second tie coat with the surface bonding of first tie coat, the second surface of second tie coat be used for with roll up the core adventitia and bond.

Optionally, the core body includes a winding tail end, the first adhesive layer includes a first region and a second region, the first region is bonded to the winding tail end, and the second region is bonded to the core body.

Optionally, the second adhesive layer is located within the first region at a projected area of the first adhesive layer.

Optionally, the second adhesive layer is located within the area where the first adhesive layer is located in the projection area of the first adhesive layer.

Optionally, the projected area of the second adhesive layer on the jellyroll partially overlaps the projected area of the first adhesive layer on the jellyroll body. Optionally, the winding ending end is located on a first side surface of the winding core body, and the first side surface is parallel to a surface where the tab of the winding core body is located.

Optionally, the second surface of the second adhesive layer has a greater adhesion than the first surface of the second adhesive layer.

Optionally, the second surface of the second adhesive layer has an adhesion force greater than 0.1 newtons per square millimeter and less than or equal to 1.2 newtons per square millimeter, and the first surface of the second adhesive layer has an adhesion force greater than 0.1 newtons per square millimeter and less than or equal to 0.8 newtons per square millimeter.

Optionally, the width of the first adhesive layer is 50% to 80% of the width of the winding core body, and the length of the first adhesive layer is 50% to 90% of the length of the winding core body.

Optionally, the width of the second adhesive layer is 30% to 60% of the width of the first adhesive layer, and the length of the second adhesive layer is 50% to 130% of the length of the first adhesive layer. Optionally, the first adhesive layer is single-sided adhesive tape, and the second adhesive layer is hot melt adhesive.

In a second aspect, an embodiment of the present application further provides a battery, including the above roll core, and further including a roll core outer film, where the roll core outer film forms an accommodating cavity, and the roll core is located in the accommodating cavity;

the first surface of the second bonding layer is bonded with the surface of the first bonding layer, and the second surface of the second bonding layer is bonded with the outer film of the winding core.

In the embodiment of this application, roll up core including rolling up core body, first tie coat and second tie coat, the adhesion force of first tie coat is greater than the adhesion force of second tie coat, the first surface of second tie coat bonds and the second surface all has the adhesion force, first tie coat with roll up the core body and bond, the first surface of second tie coat with the surface bonding of first tie coat, the second surface of second tie coat be used for with roll up the core adventitia and bond. Through set up first tie coat and second tie coat at roll core body and roll up between the core adventitia, and the adhesion stress of first tie coat is greater than the adhesion stress of second tie coat, compare in the correlation technique with the less second tie coat of adhesion stress (like the hot melt adhesive) directly bond in rolling up the core, can improve the adhesion stress between core and the roll core adventitia, thereby when having reduced physical abuse, roll up the risk of the relative displacement that core and roll core adventitia took place, improve the safety in utilization of battery.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the description of the embodiments of the present application will be briefly described below, and it is obvious that the drawings in the description below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings may be obtained according to these drawings without inventive labor.

FIG. 1 is a schematic view of a core of the related art;

fig. 2 is a first schematic structural diagram of a winding core according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a core according to an embodiment of the present application;

fig. 4 is a third structural schematic diagram of the winding core provided in the embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which this application belongs. The terms "first," "second," and the like, as used herein do not denote any order, quantity, or importance. But merely serve to distinguish between different components. Also, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships are changed accordingly.

In order to effectively prevent the phenomenon of displacement of the winding core and the possible problem of short circuit when the battery is influenced by external forces such as collision, extrusion, falling and the like, in the related art, as shown in fig. 1, a layer of hot melt adhesive is usually adhered between the winding core and the aluminum plastic film shell wrapped on the outer layer of the winding core so as to fix the relative positions of the winding core and the aluminum plastic film shell wrapped on the outer layer of the winding core. However, directly paste hot melt adhesive and book core, in the hot melt adhesive melting or solidification process, the produced stress of hot melt adhesive can all be applied to the book core, and this probably leads to the cracked risk that damages of core and book core of pole piece.

In order to solve the above problems, the winding core and the battery provided by the present application will be described in detail by specific embodiments with reference to the accompanying drawings.

Referring to fig. 2 to 4, the core 10 includes a core body 11, a first adhesive layer 12 and a second adhesive layer 13, the adhesive force of the first adhesive layer 12 is greater than the adhesive force of the second adhesive layer 13, both the first surface and the second surface of the second adhesive layer 13 have adhesive force, the first adhesive layer 12 is adhered to the core body 11, the first surface of the second adhesive layer 13 is adhered to the surface of the first adhesive layer 12, and the second surface of the second adhesive layer 13 is adhered to an outer film of the core.

The embodiment of the application is suitable for the battery with the winding core 10. Wherein, roll up the core adventitia and understand to be used for wrapping up core 10 casing to play the effect of protection internal electrode, isolated external environment, roll up the core adventitia and for example can be plastic-aluminum membrane shell body, roll up core 10 and be located the holding chamber that is formed by plastic-aluminum membrane shell body. The first adhesive layer 12 and the second adhesive layer 13 may partially overlap, and the second adhesive layer 13 may also completely overlap the first adhesive layer 12, which is not limited in this embodiment.

In the present embodiment, the determination of the magnitude of the adhesive force between the two adhesive layers is performed by bonding the first adhesive layer 12 and the second adhesive layer 13 to the surface of the core, and then pulling the first adhesive layer 12 and the second adhesive layer 13 with the same force, whereby the adhesive force of the adhesive layer which is easily peeled off is small. In contrast to the related art in which the adhesive layer is directly bonded between the core and the core outer film, the adhesive layer is peeled off from the core surface when the outer film is peeled off. In the present embodiment, when the core outer film is peeled off after the first adhesive layer 12 is additionally bonded between the second adhesive layer 13 and the surface of the core 10, the first adhesive layer 12 is not peeled off from the surface of the core 10, but peeled off between the second adhesive layer 13 and the first adhesive layer 12. Further, it can also be said that the adhesion of the second surface of the first adhesive layer 12 to the surface of the core is greater than the adhesion of the first surface of the second adhesive layer 13 to the first adhesive layer 12.

In the embodiment of the application, through set up the two-layer tie coat that the adhesion force is different between rolling up core body 11 and the roll core adventitia, and the great first tie coat 12 of adhesion force bonds with rolling up core body, the less second tie coat 13 of adhesion force bonds first tie coat 12 and roll core adventitia, compare in the correlation technique with the less second tie coat 12 of adhesion force (like the hot melt adhesive) directly bond in rolling up core 10, can improve the adhesion force between roll core 10 and the roll core adventitia, thereby when physical abuse has been reduced, roll core 10 and the risk of the relative displacement that rolls up the core adventitia and take place, the safety in utilization of battery is improved.

In an alternative embodiment, the core body 11 includes a winding tail end 111, the first adhesive layer 12 includes a first area 121 and a second area 122, the first area 121 being bonded to the winding tail end 111, and the second area 122 being bonded to the core body 11.

Wherein, roll up core 10 before the encapsulation, need to roll up the winding ending end of core 10 and carry out ending processing to the stability of core 10 is rolled up in the protection, prevents to scatter. At present, the ending mode of the winding core 10 mostly adopts direct ending of hot melt adhesive, and when the temperature of the battery rises to a preset temperature, the solid hot melt adhesive is converted into liquid which can flow and has certain viscosity, so that the winding core 10 and the aluminum plastic film outer shell are relatively fixed while ending treatment is carried out on the winding core 10; in addition, as shown in fig. 1, the ending mode of the winding core 10 can also adopt ending glue for ending treatment, and the hot melt glue is adhered to the winding core 10 beside the ending glue. No matter which mode of adopting above-mentioned, because the hot melt adhesive with roll up core 10 direct contact to the hot melt adhesive with roll up the outmost mass flow body of core body 10 or insulating coating direct contact, when the physics is abused, cause easily to roll up and take place relative displacement between core 10 and the roll core adventitia, thereby influence the safety in utilization of battery.

In this embodiment, the first adhesive layer 12 may be a finishing adhesive for finishing the winding finishing end 111 of the winding core body 11, and the second adhesive layer 13 is bonded to the surface of the first adhesive layer 12, and directly bonded to the winding core body 11 through the first adhesive layer 12 having a large adhesive force, and the second adhesive layer 13 having a small adhesive force is bonded to the first adhesive layer 12, so as to improve the stability between the winding core 10 and the winding core outer film.

In an alternative embodiment, the first adhesive layer 12 is adhered to the surface of the winding core body 11, specifically, the first area 121 of the first adhesive layer 12 is adhered to the winding tail end 111, the second area 122 of the first adhesive layer 12 is adhered to the winding core body 11, that is, a step is formed between the first area 121 and the second area 122, and the first area 121 is higher than the second area 122 by a height difference, that is, the height of the stacked piece formed by the positive electrode sheet, the separator and the negative electrode sheet.

In a specific implementation, as shown in fig. 2, the second adhesive layer 13 is located within the second region 122 in the projected area of the first adhesive layer 12.

It will be appreciated that the first region 121 of the first adhesive layer is adhered to the winding end, and the area of the second adhesive layer adhered to the surface of the first adhesive layer is smaller than the area of the first adhesive layer and smaller than the area of the second region 122.

In this embodiment, the first bonding layer 12 with a large bonding force is bonded to the winding core body 11, and the second bonding layer 13 with a small bonding force is completely located in the second region 122 of the first bonding layer 12, so that the second bonding layer does not directly contact with the outermost current collector or the outermost insulating coating of the winding core body 11, and further, the bonding force between the first bonding layer 12 and the outer film of the winding core is improved, and the risk of relative displacement between the winding core body 10 and the outer film of the winding core is reduced.

In another alternative embodiment, as shown in FIG. 3, the second region 122 of the first adhesive layer 12 is adhered to the jellyroll body 11, and the winding tail end 111 covers the first region 121 of the first adhesive layer 12, i.e., no step is formed between the first region 121 and the second region 122, and the first region 121 and the second region 122 are at the same height.

In a specific implementation, the second adhesive layer is located within the area of the first adhesive layer in the projection area of the first adhesive layer.

In another alternative embodiment, the projected area of the second adhesive layer 13 onto the jellyroll body 11 partially overlaps the projected area of the first adhesive layer 12 onto the jellyroll body 11.

In this embodiment, through setting up second tie coat 13 part and bonding in first tie coat 12, compare in the correlation technique with the less second tie coat 12 of adhesion force (like the hot melt adhesive) directly bond in rolling up core 10, can improve the adhesion force between core 10 and the core adventitia that rolls up to when the physics abuses, roll up core 10 and the risk of the relative displacement who rolls up the core adventitia and take place, improve the safety in utilization of battery.

It should be understood that, as shown in fig. 4, the first adhesive sub-layer 12 may comprise a first adhesive sub-layer and a second adhesive sub-layer, the first adhesive sub-layer is adhered to the core body 11, the second adhesive sub-layer comprises a first area 121 and a second area 122, the first area 121 is adhered to the winding tail end 111, and the second area 122 is adhered to the core body 11, because the second adhesive sub-layer has the same function and the same structure as the first adhesive layer 12 in the above embodiments, the second adhesive sub-layer 12 can also achieve all the technical effects of the above embodiments related to the first adhesive layer, and the description thereof is omitted.

In a specific implementation, one end of the second adhesive layer 13 is adhered to the first sub-adhesive layer, and the other end of the second sub-adhesive layer 12 is adhered to the second sub-adhesive layer.

It will be appreciated that in the case where the first sub-adhesive layer and the second sub-adhesive layer are separated by a relatively large distance, a partial area (between the ends) of the second adhesive layer 13 is directly adhered to the core body 11. In an alternative embodiment, the width of the second adhesive layer 13 is smaller than the width of the first adhesive layer 12, wherein the width of the second adhesive layer 13 is the dimension of the edge of the second adhesive layer 13 along the winding direction of the winding core body 11, and the width of the first adhesive layer 12 is the dimension of the edge of the first adhesive layer 12 along the winding direction of the winding core body 11

In another alternative embodiment, the length of the second adhesive layer 13 is less than the length of the first adhesive layer 12.

The length of the second adhesive layer 13 is the dimension of the other side provided with respect to the width of the second adhesive layer 13, and the length of the first adhesive layer 12 is the dimension of the other side provided with respect to the width of the first adhesive layer 12.

In another alternative embodiment, the length of second adhesive layer 13 is greater than the length of first adhesive layer 12

During concrete implementation, before roll up core 10 and encapsulate, need not to roll up core 10 through ending to glue and receive the tail end and carry out the ending and handle, still need seal and fixed processing to the both ends of rolling up core 10, to this conventional processing, the this embodiment is not repeated. Therefore, the length of the ending glue on the winding core 10 should be smaller than the length of the winding core body 11, namely, the length of the first bonding layer 12 should be smaller than the length of the winding core body 11, the second bonding layer 13 used for bonding the winding core body 11 and the outer film of the winding core can extend to the two ends of the winding core 10 on the side of the partial length.

In an alternative embodiment, the winding end 111 is located on the first side 112 of the core body 11, and the first side 112 is parallel to the tab 113 of the core body 11.

In an alternative embodiment, the width of the first adhesive layer 12 is 50% to 80% of the width of the first side, and the length of the first adhesive layer 12 is 50% to 90% of the length of the first side. It should be understood that the width of the first side surface is the dimension of the edge of the first side surface along the winding direction of the winding core body 11.

In this embodiment, the width of the first adhesive layer 12 is greater than 50% of the width of the first side surface, and the length of the first adhesive layer 12 is greater than 50% of the length of the first side surface, so as to improve the adhesive strength of the first adhesive layer 12 on the winding core body 11, and also provide an adhesive position for the second adhesive layer 13 adhered to the first adhesive layer 12, and in addition, if the width and the length of the first adhesive layer 12 on the first side surface are both too large (for example, the width is greater than 80% and the length is greater than 90%), a process problem is easily caused, and the adhesive paper is adhered, wrinkled, rolled and the like.

In an alternative embodiment, the width of the second adhesive layer 13 is 30% to 60% of the width of the first adhesive layer 12, and the length of the second adhesive layer is 50% to 130% of the length of the first adhesive layer.

In an alternative embodiment, the adhesion of the second surface of the second adhesive layer 13 is greater than the adhesion of the first surface of the second adhesive layer 13.

In an alternative embodiment, the second surface of the second adhesive layer 13 has an adhesive force greater than 0.1 newtons per square millimeter and less than or equal to 1.2 newtons per square millimeter, and the first surface of the second adhesive layer 13 has an adhesive force greater than 0.1 newtons per square millimeter and less than or equal to 0.8 newtons per square millimeter

In an alternative embodiment, the first adhesive layer 12 may be single-sided adhesive paper, and the second adhesive layer 13 may be hot melt adhesive.

The single-sided gummed paper can be high molecular polymer plastics, such as: polyethylene terephthalate PET, polyimide PI, and the like. The hot melt adhesive is used as a plastic adhesive, the physical state of the hot melt adhesive changes along with the temperature change within a certain temperature range, the chemical properties of the hot melt adhesive are unchanged, and the hot melt adhesive is non-toxic and tasteless and belongs to an environment-friendly chemical product.

During concrete implementation, single face adhesive tape pastes in rolling up core body 11, and the hot melt adhesive is located single face adhesive tape and rolls up between the core adventitia, and when battery temperature riseed to preset temperature, solid-like hot melt adhesive changed into can flow and have the liquid of certain viscidity to bond single face adhesive tape and roll up the core adventitia, and then carry out relatively fixed between core body 11 and the core adventitia of rolling up. Because the great single face adhesive tape of adhesion strength and the direct contact of rolling up core body 11, compare in the correlation technique, the hot melt adhesive is directly pasted on rolling up core body 11, and its adhesion strength is bigger.

The application still provides a battery, including as above roll up core 10, still include to roll up the core adventitia, roll up the core adventitia and form the holding chamber, roll up core 10 and be located the holding chamber, the first surface of second tie coat 13 bonds with the surface of first tie coat 12, the second surface of second tie coat 13 bonds with roll up the core adventitia. Since the technical solution of this embodiment includes all technical solutions of the above embodiments, at least all technical effects of the above embodiments can be achieved, and details are not repeated here.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (12)

1. The utility model provides a roll up core, its characterized in that, includes roll up core body, first tie coat and second tie coat, the adhesion force of first tie coat is greater than the adhesion force of second tie coat, the first surface and the second surface of second tie coat all have the adhesion force, first tie coat with roll up core body and bond, the first surface of second tie coat with the surface bonding of first tie coat, the second surface of second tie coat be used for with roll up the core adventitia and bond.

2. The winding core of claim 1, wherein the core body includes a winding tail end, and wherein the first adhesive layer comprises a first region bonded to the winding tail end and a second region bonded to the core body.

3. The winding core of claim 2, wherein the second adhesive layer is located within the second area at a projected area of the first adhesive layer.

4. The winding core of claim 2, wherein the second adhesive layer is located within the area of the first adhesive layer at the projected area of the first adhesive layer.

5. The winding core of claim 2, wherein a projected area of the second adhesive layer on the core partially overlaps a projected area of the first adhesive layer on the core body.

6. The winding core according to claim 2, wherein the winding tail end is located on a first side surface of the winding core body, and the first side surface is parallel to a surface where the tab of the winding core body is located.

7. The winding core of claim 1, wherein the second surface of the second adhesive layer has a greater adhesion than the first surface of the second adhesive layer.

8. The winding core of claim 7, wherein the second surface of the second adhesive layer has an adhesive force of greater than 0.1 newtons per square millimeter and less than or equal to 1.2 newtons per square millimeter, and the first surface of the second adhesive layer has an adhesive force of greater than 0.1 newtons per square millimeter and less than or equal to 0.8 newtons per square millimeter.

9. The winding core of claim 8, wherein the first adhesive layer has a width of 50% to 80% of the width of the core body and a length of 50% to 90% of the length of the core body.

10. The winding core of claim 9, wherein the width of the second adhesive layer is 30% to 60% of the width of the first adhesive layer and the length of the second adhesive layer is 50% to 130% of the length of the first adhesive layer.

11. The winding core according to claim 1, wherein the first adhesive layer is single-sided adhesive paper and the second adhesive layer is hot melt adhesive.

12. A battery, comprising the winding core according to any one of claims 1 to 11, and further comprising a winding core outer film forming a receiving cavity, the winding core being located in the receiving cavity;

the first surface of the second bonding layer is bonded with the surface of the first bonding layer, and the second surface of the second bonding layer is bonded with the outer film of the winding core.

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