阅读说明：本技术 胶纸、极耳及电池 (Adhesive tape, tab and battery ) 是由 林文荣 李素丽 李俊义 徐延铭 于 2021-09-27 设计创作，主要内容包括：本发明提供了一种胶纸、极耳及电池。其中,所述胶纸包括第一胶层和第二胶层,所述第一胶层包括第一子胶层,所述第二胶层设于所述第一胶层上,所述第一子胶层的软化温度低于第一预设温度。这样,通过降低所述第一子胶层的软化温度,可以使得所述胶纸在热封的过程中较早软化,在实现密封的同时,可以使密封体内部不会因高温而过度膨胀,提高热封过程的安全性。(The invention provides gummed paper, a tab and a battery. Wherein, the adhesive tape includes first glue film and second glue film, first glue film includes first sub-glue film, the second glue film is located on the first glue film, the softening temperature of first sub-glue film is less than first preset temperature. Like this, through reducing the softening temperature of first sub-glue film, can be so that the adhesive tape softens earlier at the in-process of heat-seal, when realizing sealed, can make the inside excessive expansion because of high temperature of sealing, improves the security of heat-seal process.)

1. The utility model provides a gummed paper, its characterized in that, gummed paper includes first glue film and second glue film, first glue film includes first sub-glue film, the second glue film is located on the first glue film, the softening temperature of first sub-glue film is less than first predetermined temperature.

2. The gummed paper of claim 1, wherein the softening temperature of the first sub-gum layer is 90 ℃ to 130 ℃; and/or the first sub-adhesive layer comprises at least one of ethylene modified polymer, propylene modified polymer and ethylene-propylene blending modified polymer.

3. Gummed paper as in claim 1, characterized in that the softening temperature of said second layer of glue is lower than a second preset temperature.

4. Gummed paper as in claim 3, characterized in that the softening temperature of the second gummed layer is comprised between 100 ℃ and 160 ℃; and/or the second subbing layer comprises an olefin modified polymer or a blend of a polyolefin and an olefin modified polymer, the olefin modified polymer comprises at least one of an ethylene modified polymer, a propylene modified polymer and a butylene modified polymer, and the polyolefin comprises at least one of polyethylene, polypropylene and polybutylene.

5. The gummed paper of claim 1, wherein the first glue layer further comprises a second sub-glue layer, the second sub-glue layer is arranged between the first sub-glue layer and the second glue layer, and the first sub-glue layer, the second sub-glue layer and the second glue layer are sequentially stacked;

the softening temperature of the second sub-adhesive layer is higher than that of the first sub-adhesive layer and also higher than that of the second adhesive layer.

6. The gummed paper of claim 5, wherein the softening temperature of the second sub-gum layer is 150 ℃ to 200 ℃; and/or the second sub-adhesive layer comprises at least one of propylene copolymer, propylene homopolymer, butylene copolymer and styrene copolymer.

7. Gummed paper as in claim 1, wherein the gummed paper has a thickness of 30 to 300 μ ι η.

8. A tab, which is characterized by comprising an electric conductor and tab glue, wherein the tab glue is the adhesive paper according to any one of claims 1-7;

the electric conductor comprises a first surface and a second surface which are opposite to each other in the thickness direction, the tab glue is arranged on each of the first surface and the second surface, the first glue layer is arranged on the surface of the electric conductor, and at least part of the first sub-glue layer is in contact with the surface of the electric conductor.

9. The tab as claimed in claim 8, wherein the conductor portion is wrapped by the tab compound, and both ends of the conductor in the length direction protrude from the tab compound.

10. The tab as claimed in claim 8, wherein the electrical conductor includes first and second sides opposite in width; locate the utmost point ear of first surface glue including protrusion in the first part of first side and protrusion in the second part of second side is located the utmost point ear of second surface glue including protrusion in the third part of first side and protrusion in the fourth part of second side, the first part with the third part meets, the second part with the fourth part meets.

11. A battery comprising a positive electrode tab and a negative electrode tab, wherein the positive electrode tab and/or the negative electrode tab comprises the tab according to any one of claims 8 to 10.

Technical Field

The invention relates to the technical field of batteries, in particular to gummed paper, a tab and a battery.

Background

In the lithium ion battery structure, the tab is a metal conductor that leads out the positive and negative electrodes from the battery cell, and the tab is generally composed of a metal conductor and tab glue. In the process of assembling the battery, the tab glue can seal the gap between the metal conductor and the aluminum-plastic film, so that the battery is packaged.

At present, when a lithium ion battery is charged and discharged under the conditions of high current, high voltage or high temperature, a large amount of heat is often generated, the decomposition and vaporization degree of the electrolyte inside the battery is increased, and combustible gases are generated and cannot be discharged in time, so that accidents such as fire, smoke, even explosion and the like of the battery can be caused.

It can be seen that the safety of the prior art battery is low.

Disclosure of Invention

The embodiment of the invention mainly aims to provide gummed paper, a tab and a battery, and aims to solve the technical problem of low battery safety in the prior art.

In order to achieve the above object, in a first aspect, an embodiment of the present invention provides a gummed paper, where the gummed paper includes a first gummed layer and a second gummed layer, the first gummed layer includes a first sub-gummed layer, the second gummed layer is disposed on the first gummed layer, and a softening temperature of the first sub-gummed layer is lower than a first preset temperature.

Optionally, the softening temperature of the first sub-adhesive layer is 90 ℃ to 130 ℃; and/or the first sub-adhesive layer comprises at least one of ethylene modified polymer, propylene modified polymer and ethylene-propylene blending modified polymer.

Optionally, the softening temperature of the second glue layer is lower than a second preset temperature.

Optionally, the softening temperature of the second glue layer is 100 ℃ to 160 ℃; and/or the second subbing layer comprises an olefin modified polymer or a blend of a polyolefin and an olefin modified polymer, the olefin modified polymer comprises at least one of an ethylene modified polymer, a propylene modified polymer and a butylene modified polymer, and the polyolefin comprises at least one of polyethylene, polypropylene and polybutylene.

Optionally, the first adhesive layer further includes a second sub-adhesive layer, the second sub-adhesive layer is disposed between the first sub-adhesive layer and the second adhesive layer, and the first sub-adhesive layer, the second sub-adhesive layer and the second adhesive layer are sequentially stacked;

the softening temperature of the second sub-adhesive layer is higher than that of the first sub-adhesive layer and also higher than that of the second adhesive layer.

Optionally, the softening temperature of the second sub-adhesive layer is 150 ℃ to 200 ℃; and/or the second sub-adhesive layer comprises at least one of propylene copolymer, propylene homopolymer, butylene copolymer and styrene copolymer.

Optionally, the thickness of the tab glue is 30 μm to 300 μm.

In a second aspect, an embodiment of the present invention provides a tab, including an electrical conductor and tab glue, where the tab glue is the gummed paper provided in the first aspect;

the electric conductor comprises a first surface and a second surface which are opposite to each other in the thickness direction, the tab glue is arranged on each of the first surface and the second surface, the first glue layer is arranged on the surface of the electric conductor, and at least part of the first sub-glue layer is in contact with the surface of the electric conductor.

Optionally, the electric conductor part is wrapped by the tab glue, and two ends of the electric conductor in the length direction protrude out of the tab glue.

Optionally, the electrical conductor comprises a first side and a second side opposite in the width direction; locate the utmost point ear of first surface glue including protrusion in the first part of first side and protrusion in the second part of second side is located the utmost point ear of second surface glue including protrusion in the third part of first side and protrusion in the fourth part of second side, the first part with the third part meets, the second part with the fourth part meets.

In a third aspect, the embodiment of the present invention further provides a battery, which includes a positive electrode tab and a negative electrode tab, where the positive electrode tab and/or the negative electrode tab includes the tab provided in the second aspect.

The invention provides gummed paper, a tab and a battery. Wherein, the adhesive tape includes first glue film and second glue film, first glue film includes first sub-glue film, the second glue film is located on the first glue film, the softening temperature of first sub-glue film is less than first preset temperature. Like this, through reducing the softening temperature of first sub-glue film, can be so that the adhesive tape softens earlier at the in-process of heat-seal, when realizing sealed, can make the inside excessive expansion because of high temperature of sealing, improves the security of heat-seal process.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a gummed paper provided by the present invention;

fig. 2 is a schematic structural diagram of a tab provided by the present invention;

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a cross-sectional view taken along line B-B of FIG. 2;

fig. 5 is a flowchart of a method for manufacturing a tab according to the present invention.

Description of reference numerals:

10. an electrical conductor; 20. gummed paper/tab gum; 21. a first sub-adhesive layer; 22. a second sub-adhesive layer; 23. a second adhesive layer; 11. a tab projecting portion; 12. and E, tab welding part.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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 invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

Referring to fig. 1, an embodiment of the invention provides a gummed paper 20.

The adhesive tape 20 comprises a first adhesive layer and a second adhesive layer 23, wherein the first adhesive layer comprises a first sub adhesive layer 21, the second adhesive layer 23 is arranged on the first adhesive layer, and the softening temperature of the first sub adhesive layer 21 is lower than a first preset temperature.

In the embodiment of the invention, the softening temperature is the temperature at which the adhesive layer reaches a set value under a certain condition, and the first preset temperature can be set to be lower. Like this, in the heat-seal process, when the inside temperature of seal risees gradually, first sub glue film 21 can soften earlier to make the inside gaseous exhaust because of high temperature produces of seal, avoid the seal because of gaseous overexpansion explosion even, improve the security of heat-seal process.

Optionally, the softening temperature of the first sub-adhesive layer 21 is 90 ℃ to 130 ℃; and/or, the first sub-adhesive layer 21 includes at least one of an ethylene modified polymer, a propylene modified polymer, and an ethylene-propylene blending modified polymer.

In this embodiment, the first sub-adhesive layer 21 may be a high molecular polymer layer with a low softening temperature. Alternatively, the first sub-bondline 21 may have a melt index of 7g/10min to 12g/10min, which is used to characterize the viscous flow properties of the bondline in the molten state. Alternatively, the crystallinity of the first sub-paste layer 21 may be 35% to 65%, which is used to represent the proportion of the crystalline region in the second paste layer 23. Optionally, the thickness of the first glue layer 21 is 10 μm to 100 μm.

In particular, the modification method of the ethylene modified polymer, the propylene modified polymer or the ethylene-propylene blend modified polymer may be graft modification. Specifically, the graft modification may be graft modification of maleic anhydride and the like, or graft modification of acrylic acid and the derivative thereof, or graft modification of maleic anhydride and the like and graft modification of acrylic acid and the derivative thereof may be mixed. The graft ratio of the graft modification may be 0.3% to 1.2%, which may be determined according to the actual situation, and the embodiment of the present invention is not limited herein.

Optionally, the softening temperature of the second glue layer 23 is lower than the second preset temperature.

In this embodiment, the temperature can set up lowerly in advance to the second, and like this, at the heat-seal in-process, the shorter time of heating can reach the softening temperature of second glue film 23 to accomplish the melting heat-seal between second glue film 23 and the seal, reduced the heat-seal time, not only improved heat-seal efficiency, still reduced the required energy consumption of heat-seal.

It should be noted that the first preset temperature and the second preset temperature may be the same or different, and are determined according to actual situations, and the embodiment of the present invention is not limited herein.

In this embodiment, optionally, the softening temperature of the second adhesive layer 23 is 100 ℃ to 160 ℃; and/or, second bondline 23 comprises an olefin-modified polymer comprising at least one of an ethylene-modified polymer, a propylene-modified polymer, and a butylene-modified polymer, or a blend of a polyolefin comprising at least one of polyethylene, polypropylene, and polybutylene, and an olefin-modified polymer.

In this embodiment, the second adhesive layer 23 may be a polymer layer with a low softening temperature. Alternatively, the second glue layer 23 may have a melt index of 7g/10min to 12g/10min and a crystallinity of 40% to 65%. Optionally, the thickness of the second glue layer 23 is 10 μm to 100 μm.

Optionally, the first adhesive layer further includes a second sub-adhesive layer 22, the second sub-adhesive layer 22 is disposed between the first sub-adhesive layer 21 and the second adhesive layer 23, and the first sub-adhesive layer 21, the second sub-adhesive layer 22 and the second adhesive layer 23 are sequentially stacked; the softening temperature of the second sub-adhesive layer 22 is higher than the softening temperature of the first sub-adhesive layer 21 and also higher than the softening temperature of the second adhesive layer 23.

In this embodiment, as shown in fig. 1, the adhesive paper 20 has a three-layer structure, which specifically includes a first sub-adhesive layer 21, a second sub-adhesive layer 22, and a second adhesive layer 23, which are sequentially stacked to form the adhesive paper 20. Alternatively, the first adhesive layer 21, the intermediate layer 23, and the second adhesive layer 23 may be sequentially bonded and laminated.

The second sub-adhesive layer 22 may serve as an intermediate skeleton layer to provide an integral mechanical support for the adhesive paper 20. Since the softening temperature of the second sub-adhesive layer 22 is higher than the softening temperature of the first sub-adhesive layer 21 and higher than the softening temperature of the second adhesive layer 23, when the heating temperature reaches the softening temperature of the second adhesive layer 23 during the heat-sealing process, the second sub-adhesive layer 22 is not softened, so that the stability of the adhesive tape 20 can be improved.

In this embodiment, optionally, the softening temperature of the second sub-adhesive layer 22 is 150 ℃ to 200 ℃; and/or the second subbing layer 22 comprises at least one of propylene copolymer, propylene homopolymer, butylene copolymer and styrene copolymer.

In the embodiment, the melt index of the second sub-adhesive layer 22 may be 3g/10min to 7g/10min, and the crystallinity may be 55% to 85%. Optionally, the thickness of the second sub-adhesive layer 22 is 10 μm to 100 μm.

Optionally, the adhesive paper 20 has a thickness of 30 μm to 300 μm.

The embodiment of the invention also provides a tab. As shown in fig. 2 to 4, the tab includes an electrical conductor 10 and tab glue, where the tab glue is a gummed paper 20 provided in an embodiment of the present invention, and is hereinafter referred to as tab glue 20. The electric conductor 10 comprises a first surface and a second surface which are opposite to each other in the thickness direction, the first surface and the second surface are both provided with tab glue 20, the first glue layer is arranged on the surface of the electric conductor 20, and at least part of the first sub-glue layer 21 is in contact with the surface of the electric conductor 20.

Note that, as shown in fig. 2, the a-a direction is the width direction of the conductor 10, the B-B direction is the length direction of the conductor 10, and as shown in fig. 3 and 4, the C-C direction is the thickness direction of the conductor 10. The first surface may be understood as an upper surface as shown in fig. 3 and 4, and the second surface may be understood as a lower surface as shown in fig. 3 and 4.

In this embodiment, the first sub-adhesive layer 21 can be used as a metal-philic layer, the second adhesive layer 23 can be used as a heat sealing layer, and the second adhesive layer 23 is heat sealed with a battery case (mainly referred to as an aluminum plastic film) to seal the battery. In the heat-seal process, the inside temperature of battery risees gradually, and first sub glue film 21 can soften earlier to expose the micropore on electric conductor 10 surface, make the inside gas that produces because of the electrolyte liquefaction of battery can be followed the micropore in time gets rid of, reduces the expanded degree of battery, reduces the risk that the battery was fired on, was smoked even exploded, and then improves the security of battery.

In a specific implementation, the electrical conductor 10 and the tab glue 20 may be bonded by at least one bonding method including, but not limited to, high-frequency welding and hot-press bonding, which may be determined according to practical situations, and the embodiment of the present invention is not limited herein.

It should be noted that, in this embodiment, the tab includes all technical features of the adhesive tape provided in the above embodiment, and can achieve all beneficial effects that can be achieved by the adhesive tape in the above embodiment, and specific reference may be made to the explanation of the above embodiment, and details are not described here again.

In an alternative embodiment, the softening temperature of the second adhesive layer 23 is lower than the second preset temperature. In the heat-seal process, the shorter time of heating can reach the softening temperature of second glue film 23 to accomplish the melting heat-seal between second glue film 23 and the battery case, reduced encapsulation time between utmost point ear and the battery case, and reduced encapsulation temperature between utmost point ear and the battery case, and then improved the generation efficiency of battery, reduced the production energy consumption of battery simultaneously.

Optionally, the electric conductor 10 is partially wrapped by the tab glue 20, and both ends of the electric conductor 10 in the length direction protrude from the tab glue 20.

In this embodiment, as shown in fig. 2 and fig. 3, a part of the middle of the conductive body 10 is wrapped by the tab glue 20, that is, the tab glue 20 is disposed on the surface of the part along the width direction and the thickness direction, so that the tab glue 20 can seal all gaps between the tabs and the battery case, and further improve the sealing effect of the battery.

In this embodiment, the tab glue 20 may divide the electric conductor 10 into a tab protruding portion 11 and a tab welding portion 12, and the tab protruding portion 11 and the tab welding portion 12 are fixedly connected. In an alternative embodiment, the tab protruding portion 11 and the tab welding portion 12 are fixedly connected by a connection method including, but not limited to, ultrasonic welding, laser welding, arc welding and riveting, in this embodiment, the tab protruding portion 11 and the tab welding portion 12 may be made of different conductive materials or the same conductive material. In another alternative embodiment, the tab protruding portion 11 and the tab welding portion 12 are an integrated electrical conductor. The conductive material includes, but is not limited to, at least one of aluminum, nickel, copper, aluminum nickel alloy, aluminum silver alloy, nickel silver alloy, zinc copper alloy, copper silver alloy, nickel-plated copper, and nickel-plated aluminum.

Optionally, the conductive body 10 includes a first side and a second side opposite in the width direction; locate the tab glue 20 of first surface including protrusion in the first part of first side and protrusion in the second part of second side is located the tab glue 20 of second surface including protrusion in the third part of first side and protrusion in the fourth part of second side, the first part with the third part meets, the second part with the fourth part meets.

It should be noted that the first side may be understood as a left side as shown in fig. 3, and the second side may be understood as a right side as shown in fig. 3. The tab compound 20 provided on the first surface may be understood as a tab compound 20 on the upper side of the dotted line as shown in fig. 3, the first portion may be understood as a portion on the left side of the tab compound 20 which is not covered with the electrical conductor 10, and the second portion may be understood as a portion on the right side of the tab compound 20 which is not covered with the electrical conductor 10. The tab compound 20 provided on the second surface may be understood as a tab compound 20 on the lower side of the dotted line as shown in fig. 3, the third portion may be understood as a portion on the left side of the tab compound 20 which is not covered with the electrical conductor 10, and the fourth portion may be understood as a portion on the right side of the tab compound 20 which is not covered with the electrical conductor 10.

In this embodiment, after the tab glue 20 is disposed on the upper surface of the electric conductor 10 and the tab glue 20 is disposed on the lower surface of the electric conductor 10, the tab glue protruding from both sides of the electric conductor 10 in the width direction can be connected in a hot-pressing manner, so that the tab glue 20 can seal all gaps between the tabs and the battery case, and the sealing effect of the battery is further improved.

The embodiment of the invention also provides a battery, which comprises a positive plate and a negative plate, wherein the positive plate and/or the negative plate comprises the tab.

It should be noted that, in this embodiment, the battery includes all technical features of the tab provided in the above embodiment, and can achieve all beneficial effects that can be achieved by the tab in the above embodiment, and specific reference may be made to the explanation of the above embodiment, which is not described herein again.

Referring to fig. 5, an embodiment of the present invention further provides a method for manufacturing a tab.

As shown in fig. 5, the method for manufacturing the tab includes:

step 501, forming a conductor;

step 501, forming tab glue; the tab glue comprises a first glue layer and a second glue layer, and the first glue layer comprises a first sub-glue layer;

step 501, arranging the tab glue on two opposite surfaces in the thickness direction of the electric conductor to obtain a tab; the first adhesive layer is arranged on the surface of the electric conductor, at least part of the first sub adhesive layer is in contact with the surface of the electric conductor, the second adhesive layer is arranged on one side of the first adhesive layer, which is back to the electric conductor, and the softening temperature of the first sub adhesive layer is lower than a first preset temperature.

In a specific implementation, the electric conductor may be an electric conductor subjected to an activation treatment and a passivation treatment.

The activation treatment is to perform operations such as polishing, ultrasonic cleaning, alkali washing, acid washing and the like on the electric conductor to be treated so as to remove oil stains and oxide layers on the surface of the electric conductor, so that the surface roughness of the electric conductor is in a first preset range. The first predetermined range may be 0.2 μm to 2.5 μm, which may be determined according to practical situations, and the embodiment of the present invention is not limited herein.

The passivation treatment can be carried out by using one or more of chromate passivation treatment, trivalent chromium passivation treatment, zirconate passivation, titanate passivation and molybdate passivation on the electric conductor to be treated so as to form a passivation film which is resistant to acid-base corrosion and oxidation and can be effectively bonded, sealed and attached with tab glue on the surface of the electric conductor, wherein the thickness of the passivation film is within a second preset range. The second predetermined range may be 1nm to 35nm, which may be determined according to practical situations, and the embodiment of the present invention is not limited herein.

The tab glue can be prepared by laminating and bonding the first glue layer and the second glue layer and carrying out surface treatment on the tab glue. The polar functional group and the surface tension of the high molecular polymer of each adhesive layer in the tab adhesive can be enhanced by carrying out surface treatment, the joint sealing property of the first sub adhesive layer and the surface of the electric conductor in the tab adhesive is improved, and the heat-seal sealing property between the second adhesive layer and the battery shell of the tab adhesive can also be improved.

The surface treatment may be one or more of corona treatment, chemical treatment, photochemical treatment. Wherein, the technological parameters of the corona treatment are as follows: the voltage can be 10KV to 30KV, the frequency can be 10kHz to 25kHz, and the electrode gap in corona treatment can be 1mm to 2.5 mm. The chemical treatment may be a strong oxidation treatment using potassium permanganate or a soaking treatment using a potassium dichromate-sulfuric acid mixed solution. The photochemical treatment may be irradiation with ultraviolet light having a wavelength of 190nm to 400 nm. The specific treatment method and process parameters of the surface treatment can be determined according to actual conditions, and the embodiment of the invention is not limited herein. Optionally, the surface tension of the tab glue after surface treatment can be 30N/m and less than or equal to 70N/m.

The utmost point ear that obtains is made to this embodiment, the softening temperature of first sub glue film is lower, at the in-process that the inside temperature of battery risees gradually, first sub glue film can soften earlier to expose the micropore on electric conductor surface for the inside gas that produces because of electrolyte liquefaction of battery can be followed the micropore in time gets rid of reduces the expanded degree of battery, reduces the risk that the battery is fired, is smoked even explosion, and then improves the security of battery.

It should be noted that the tab manufactured in this embodiment includes all technical features of the tab provided in the above embodiment, and all beneficial effects that can be achieved by the tab in the above embodiment can be achieved.

For ease of understanding, several examples of embodiments of the present invention and comparative examples are described herein.

Example 1

The thickness of the electric conductor is 0.1mm, the width is 8mm, and the lug welding part and the lug extending part of the electric conductor are both aluminum metal.

The thickness of the tab glue is 80 μm. The thickness of the first sub-adhesive layer is 20 micrometers, the first sub-adhesive layer is a polyethylene and succinic anhydride melt graft modified polymer, the grafting rate is 1.0%, the softening temperature of the first sub-adhesive layer is 115 ℃, the melt index is 12g/10min, and the crystallinity is 36%. The thickness of the second sub-adhesive layer is 40 micrometers, the second sub-adhesive layer is made of propylene copolymer, the softening temperature of the second sub-adhesive layer is 150 ℃, the melt index of the second sub-adhesive layer is 5g/10min, and the crystallinity of the second sub-adhesive layer is 60%. The thickness of the second glue layer is 20 mu m. The second adhesive layer is an ethylene-propylene copolymerization modified polymer, the softening temperature of the second adhesive layer is 130 ℃, the melt index is 9g/10min, and the crystallinity is 48%.

In this embodiment, the conductor made of aluminum metal is subjected to activation treatment such as polishing, ultrasonic cleaning, alkali washing, and acid washing, so that the roughness of the surface of the conductor reaches 1.3 μm. Then, the conductor was subjected to chromate passivation to obtain an aluminum metal conductor having a passivation film thickness of 13 nm. And carrying out corona treatment on the tab glue so that the surface dyne value of the tab glue reaches 56 mN/m. And attaching the treated electric conductor and the tab glue through high-frequency welding to prepare the tab.

Example 2

The thickness of the electric conductor is 0.1mm, the width is 8mm, and the lug welding part and the lug extending part of the electric conductor are both made of nickel metal.

The thickness of the tab glue is 80 μm. The thickness of the first sub-adhesive layer is 20 micrometers, the first sub-adhesive layer is a polymer formed by melt graft modification of polypropylene and isocyanate compounds, the grafting rate is 1.2%, the softening temperature of the first sub-adhesive layer is 130 ℃, the melt index is 10g/10min, and the crystallinity is 40%. The thickness of the second sub-adhesive layer is 50 micrometers, the second sub-adhesive layer is a propylene homopolymer, the softening temperature of the second sub-adhesive layer is 160 ℃, the melt index is 5.2g/10min, and the crystallinity is 68%. The thickness of the second glue layer is 20 mu m. The second adhesive layer is a blending modified polymer of propylene and thermoplastic polyurethane, the softening temperature of the second adhesive layer is 125 ℃, the melt index is 10g/10min, and the crystallinity is 45%.

In this embodiment, the surface roughness of the conductive body made of a nickel metal material is made to reach 0.8 μm by performing activation processing such as polishing, ultrasonic cleaning, alkali washing, and acid washing. And then, passivating the conductor by trivalent chromium salt to obtain the nickel metal conductor with the thickness of a passivation film of 9 nm. And treating the tab glue by a potassium permanganate solution to enable the surface dyne value of the tab glue to reach 44 mN/m. And attaching the treated electric conductor and the tab glue in a hot pressing mode to prepare the tab.

Example 3

The thickness of the electric conductor is 0.1mm, the width is 8mm, and the lug welding part and the lug extending part of the electric conductor are made of nickel metal in an integrated mode.

The thickness of the tab glue is 150 μm. The thickness of the first sub-adhesive layer is 30 micrometers, the first sub-adhesive layer is a polyethylene and acrylic acid melt graft modified polymer, the grafting rate is 1%, the softening temperature of the first sub-adhesive layer is 105 ℃, the melt index is 12g/10min, and the crystallinity is 35%. The thickness of the second sub-adhesive layer is 60 micrometers, the second sub-adhesive layer is a butylene homopolymer, the softening temperature of the second sub-adhesive layer is 165 ℃, the melt index is 4.5g/10min, and the crystallinity is 70%. The thickness of the second glue layer is 60 mu m. The second adhesive layer is an ethylene-propylene copolymerization modified polymer, the softening temperature of the second adhesive layer is 130 ℃, the melt index is 10g/10min, and the crystallinity is 45%.

In this embodiment, the surface roughness of the conductive body made of a nickel metal material is 0.7 μm by performing activation processing such as polishing, ultrasonic cleaning, alkali washing, and acid washing. And then, carrying out chromate passivation treatment on the conductor to obtain the nickel metal conductor with the thickness of a passivation film of 12 nm. And treating the tab glue by a potassium permanganate solution to enable the surface dyne value of the tab glue to reach 46 mN/m. And attaching the treated electric conductor and the tab glue in a high-frequency welding mode to prepare the tab.

Comparative example 1

The thickness of the electric conductor is 0.1mm, the width is 8mm, and the lug welding part and the lug extending part of the electric conductor are both aluminum metal. And (3) using a relief printing glue with the thickness of 80 mu m as the tab glue, and attaching the tab glue to the surface of the electric conductor to prepare the tab.

Comparative example 2

The thickness of the electric conductor is 0.1mm, the width is 8mm, and the lug welding part and the lug extending part of the electric conductor are both made of nickel metal. And (3) using a relief printing glue with the thickness of 80 mu m as the tab glue, and attaching the tab glue to the surface of the electric conductor to prepare the tab.

The above-described examples 1 to 3 and comparative examples 1 to 2 were subjected to an electrolyte resistance test, an adhesive strength test, a heat-sealing temperature test, a heat-sealing strength test and an oven temperature storage test.

The electrolyte resistance test means that 10 tabs in the above examples 1 to 3 and comparative examples 1 to 2 are respectively put into an aluminum plastic film bag filled with electrolyte, and the tabs are ensured to be completely immersed by the electrolyte. Sealing the aluminum plastic film bag, storing the aluminum plastic film bag in a constant-temperature oven at 85 ℃ for 48 hours, taking out the sample bag after the test is finished, cleaning the lug, observing whether the lug glue and the electric conductor are layered or not, and confirming the laminating sealing state of the lug after resisting electrolyte.

The adhesion strength test is to test the adhesion strength between the tab and the electrical conductor using a universal tensile testing machine for the tabs in examples 1 to 3 and comparative examples 1 to 2.

The heat-sealing temperature test refers to the temperature required when the heat-sealing compression rate of the tab adhesive is 65% by adopting a seal head to carry out heat sealing on the tabs in the above examples 1-3 and comparative examples 1-2, fixing the unified packaging pressure and packaging time, and testing.

The heat seal strength test refers to heat sealing the tabs in the examples 1 to 3 and the comparative examples 1 to 2 with the aluminum-plastic film of the same specification respectively, performing hard end socket heat seal under the condition that the heat seal thickness retention rate is ensured to be 80%, and testing the heat seal strength of the tabs and the aluminum-plastic film after heat seal.

The furnace temperature storage test refers to that the lugs in the embodiments 1-3 and the comparative examples 1-2 are subjected to welding, sheet making, winding, packaging, baking, formation, sorting, capacity grading and other procedures by adopting the same battery model, the same production line and an operation machine table to prepare the battery, the good full-charge battery is taken to be subjected to a constant temperature furnace temperature storage test at 130 ℃ for 1h, and after the test is finished, the safety condition of the battery and the condition that whether the position of the top seal lug is open or not are confirmed.

The test results are shown in table 1. The electrolyte resistance in table 1 is a test result corresponding to the electrolyte resistance test, the adhesive strength is a test result corresponding to the adhesive strength test, the heat-sealing temperature is a test result corresponding to the heat-sealing temperature test, the heat-sealing strength is a test result corresponding to the heat-sealing strength test, and the furnace temperature result is a test result corresponding to the furnace temperature storage test.

TABLE 1 test results of examples 1-3 and comparative examples 1-2

The electrolyte resistance and the bonding strength in table 1 can be obtained, and the tab provided by the embodiment of the invention can ensure the bonding sealing property and the electrolyte resistance of the tab. The heat-sealing temperature in the table 1 can be obtained, the tab provided by the embodiment of the invention can effectively reduce the heat-sealing temperature, greatly reduce the production energy consumption, shorten the time required by the temperature rise of the end socket and achieve the effect of improving the production efficiency. The heat seal strength in the table 1 can be obtained, and the tab provided by the embodiment of the invention can improve the bonding tightness between the tab and the aluminum plastic film. The furnace temperature results in table 1 can show that the first sub-adhesive layer in the tab provided by the embodiment of the invention is made of a bonding material with a low melting point, so that the safe use of the battery can be ensured.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.