CN213636222U

CN213636222U - Lithium battery negative pole tab

Info

Publication number: CN213636222U
Application number: CN202023219166.2U
Authority: CN
Inventors: 张华生
Original assignee: Dongguan Huachuang New Power Co ltd
Current assignee: Dongguan Huachuang New Power Co ltd
Priority date: 2020-12-28
Filing date: 2020-12-28
Publication date: 2021-07-06
Anticipated expiration: 2030-12-28

Abstract

The utility model relates to a lithium cell technical field discloses a lithium cell negative pole utmost point ear, including negative pole auricle, the hot melt of negative pole auricle upper and lower both sides middle part has utmost point ear to glue, negative pole auricle includes weld part and contact site, utmost point ear glues inside PP layer, functional layer and the PP layer down of still including, the weld part upper surface is provided with a plurality of welding wire. The utility model discloses in, through be provided with a plurality of welding wire at the weld part upper surface, when needs external output wire, take the electric iron to do the preheating to the weld part of battery, after preheating a period, then heat the welding wire with the electric iron, with the supplementary welding wire melt shaping of flatiron, be convenient for connect output wire, the weld part top is provided with the arc chamfer, the sharpness of strap edges and corners has been reduced, the ability of impaling of strap to utmost point ear gum and plastic-aluminum membrane CPP layer has been reduced, the possibility of the aluminium lamination contact in strap and the plastic-aluminum membrane has further been reduced, the security of soft-packing lithium cell has further been improved.

Description

Lithium battery negative pole tab

Technical Field

The utility model belongs to the technical field of the lithium cell, specifically be a lithium cell negative pole utmost point ear.

Background

A "lithium battery" is a type of battery using a nonaqueous electrolyte solution with lithium metal or a lithium alloy as a positive/negative electrode material. Because the chemical characteristics of lithium metal are very active, the requirements on the environment for processing, storing and using the lithium metal are very high. With the development of scientific technology, lithium batteries have become the mainstream. Lithium batteries can be broadly classified into two types: lithium metal batteries and lithium ion batteries. Lithium ion batteries do not contain lithium in the metallic state and are rechargeable. The fifth generation lithium metal battery of rechargeable battery was born in 1996, and the safety, specific capacity, self-discharge rate and cost performance ratio of the rechargeable battery are all superior to those of a lithium ion battery, namely a tab, which is a raw material of a lithium ion polymer battery product;

the tab glue for the lithium battery tab in the prior art is usually of a single-layer structure, so that when the flexible package lithium ion battery is packaged, the outer surface layer of the tab glue and the heat seal layer of the aluminum plastic film are fused together and are difficult to separate. If the packaging defective products appear, the winding core in the soft-packaging lithium ion battery is difficult to recover in a undamaged way, and secondary packaging cannot be carried out even if the tab glue is melted in a heating way.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a: the lithium battery tab glue aims to solve the problem that the tab glue for the lithium battery tab in the prior art is usually of a single-layer structure, so that when a flexible package lithium battery is packaged, the outer surface layer of the tab glue and a heat sealing layer of an aluminum plastic film are fused together and are difficult to separate. If the encapsulation defective products appear, just hardly can not retrieve the book core inside the soft-packing lithium ion battery undamaged, even melt the utmost point ear glue through the mode of heating, also can't carry out secondary packaging's problem, provide a lithium cell negative pole utmost point ear.

The utility model adopts the technical scheme as follows: the utility model provides a lithium cell negative pole utmost point ear, includes negative pole auricle, negative pole auricle upper and lower both sides middle part hot melt has connect utmost point ear to glue, negative pole auricle includes weld part and contact site, utmost point ear glues inside PP layer, functional layer and the PP layer down of still including, the weld part upper surface is provided with a plurality of welding wire.

In a preferred embodiment, the upper PP layer is located at the outermost layer of the tab glue, the functional layer is located at the bottom of the upper PP layer, and the lower PP layer is located at the bottom of the lower PP layer.

In a preferred embodiment, the negative electrode tab is nickel-plated copper, which has higher stability than a pure copper tab and lower resistance than a pure nickel tab.

In a preferred embodiment, the upper PP layer, the functional layer and the lower PP layer are all 0.07mm thick.

In a preferred embodiment, the upper PP layer is a polyethylene melting point of 140 degrees celsius, the functional layer is a polyvinylidene fluoride melting point of 170 degrees celsius, the lower PP layer is a polytrifluoroethylene melting point of 190 degrees celsius, and when the tab is packaged, the packaging temperature is only required to be set above the melting point of the upper PP layer and below the melting point of the functional layer. When the upper PP layer is molten, the functional layer is still solid due to the fact that the packaging temperature does not reach the melting point of the functional layer. If the top seal defective products appear after the encapsulation is finished, the packaging film and the winding core can be rapidly separated after the melting of the top seal area at the same temperature as the temperature when the pole lugs are encapsulated, the separated winding core structure is not damaged, the upper PP layer of the pole lug glue is peeled off, but the functional layer still has a complete structure, and the sealing performance of the secondary encapsulation of the flexible package lithium ion battery can be ensured.

In a preferred embodiment, the top of the welding part is provided with an arc-shaped chamfer, so that the sharpness of the edge of the metal belt is reduced, the piercing capability of the metal belt on the tab glue and the CPP layer of the aluminum plastic film is reduced, the possibility of the contact of the metal belt and the aluminum layer in the aluminum plastic film is further reduced, and the safety of the flexible package lithium battery is further improved.

To sum up, owing to adopted above-mentioned technical scheme, the beneficial effects of the utility model are that:

1. the utility model discloses in, utmost point ear glue is inside still to include PP layer, functional layer and lower PP layer, goes up the PP layer and is 140 degrees centigrade for the polyethylene melting point, and the functional layer is 170 degrees centigrade for the polyvinylidene fluoride melting point, and lower PP layer is 190 degrees centigrade for the polytrifluoroethylene melting point, only need when encapsulation utmost point ear department with the encapsulation temperature set up on the melting point on last PP layer, under the melting point of functional layer can. When the upper PP layer is molten, the functional layer is still solid due to the fact that the packaging temperature does not reach the melting point of the functional layer. If the top seal defective products appear after the encapsulation is finished, the packaging film and the winding core can be rapidly separated after the melting of the top seal area at the same temperature as the temperature when the pole lugs are encapsulated, the separated winding core structure is not damaged, the upper PP layer of the pole lug glue is peeled off, but the functional layer still has a complete structure, and the sealing performance of the secondary encapsulation of the flexible package lithium ion battery can be ensured.

2. The utility model discloses in, through be provided with a plurality of welding wire at the weld part upper surface, when needs external output wire, take the electric iron to do the preheating to the weld part of battery, after preheating a period, then heat the welding wire with the electric iron, with the supplementary welding wire melt shaping of flatiron, be convenient for connect output wire, the weld part top is provided with the arc chamfer, the sharpness of strap edges and corners has been reduced, the ability of impaling of strap to utmost point ear gum and plastic-aluminum membrane CPP layer has been reduced, the possibility of the aluminium lamination contact in strap and the plastic-aluminum membrane has further been reduced, the security of soft-packing lithium cell has further been improved.

Drawings

Fig. 1 is a schematic diagram of a structure of a lithium battery negative electrode tab of the present invention;

fig. 2 is a top view of a negative electrode tab of a lithium battery according to the present invention;

fig. 3 is the utility model relates to a material picture that utmost point ear glued in lithium cell negative pole utmost point ear.

The labels in the figure are: 1-negative pole lug, 2-lug glue, 3-welding part, 4-contact part, 5-welding wire, 6-upper PP layer, 7-functional layer and 8-lower PP layer.

Detailed Description

To make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the embodiments of the present invention are combined to clearly and completely describe the technical solution in the embodiments of the present invention, and obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

Referring to fig. 1-3, a lithium battery negative pole tab comprises a negative pole tab 1, the negative pole tab 1 is nickel-plated with copper, and has higher stability compared with a pure copper tab, and has lower resistance compared with a pure nickel tab, tab glue 2 is hot-melted in the middle of the upper side and the lower side of the negative pole tab 1, the negative pole tab 1 comprises a welding part 3 and a contact part 4, the top of the welding part 3 is provided with an arc chamfer, the sharpness of a metal strip corner is reduced, the piercing capability of the metal strip on the tab glue and an aluminum plastic film CPP layer is reduced, the possibility of the metal strip contacting an aluminum layer in the aluminum plastic film is further reduced, the safety of a soft package lithium battery is further improved, the tab glue 2 further comprises an upper PP layer 6, a functional layer 7 and a lower PP layer 8, the upper surface of the welding part 3 is provided with a plurality of welding wires 5, the upper PP layer 6 is located on the outermost layer of, the lower PP layer 8 is located at the bottom of the lower PP layer 8, the thicknesses of the upper PP layer 6, the functional layer 7 and the lower PP layer 8 are all 0.07mm, the melting point of polyethylene on the upper PP layer 6 is 140 ℃, the melting point of polyvinylidene fluoride on the functional layer 7 is 170 ℃, the melting point of polytrifluoroethylene on the lower PP layer 8 is 190 ℃, and when the lug is packaged, the packaging temperature is only required to be set above the melting point of the upper PP layer 6 and below the melting point of the functional layer 7. When the upper PP layer 6 melts, the functional layer 7 remains solid as the encapsulation temperature has not yet reached the melting point of the functional layer 7. If the top sealing defective products appear after the encapsulation is finished, the packaging film and the winding core can be rapidly separated after the melting of the top sealing area at the same temperature as the temperature when the pole lugs are encapsulated, the structure of the separated winding core is not damaged, the upper PP layer 6 of the pole lug glue is peeled off, but the functional layer 7 still has a complete structure, and the sealing performance of the secondary encapsulation of the flexible packaging lithium ion battery can be ensured.

The utility model discloses lithium battery negative pole utmost point ear, utmost point ear glue 2 inside still include PP layer 6, functional layer 7 and PP layer 8 down, go up PP layer 6 and be 140 degrees centigrade for the polyethylene melting point, functional layer 7 is 170 degrees centigrade for the polyvinylidene fluoride melting point, and lower PP layer 8 is 190 degrees centigrade for the polytrifluoroethylene melting point, only need when encapsulation utmost point ear department with the encapsulation temperature set up on the melting point of last PP layer 6, under the melting point of functional layer 7 can. When the upper PP layer 6 melts, the functional layer 7 remains solid as the encapsulation temperature has not yet reached the melting point of the functional layer 7. If the top sealing defective products appear after the packaging is finished, the packaging film and the winding core can be quickly separated after the top sealing area is melted at the same temperature as that of the packaging of the tabs, the structure of the separated winding core is not damaged, the upper PP layer 6 of tab glue is stripped, but the functional layer 7 still has a complete structure, and the sealing performance of the secondary packaging of the flexible packaging lithium ion battery can be ensured;

the utility model discloses lithium cell negative pole utmost point ear, through be provided with a plurality of welding wire 5 at 3 upper surfaces of weld part, when needs external output wire, take the electric iron to do the preheating to the weld part 3 of battery, after preheating a period, then heat welding wire 5 with the electric iron, with 5 melt shaping of auxiliary welding wire of flatiron, be convenient for connect output wire, 3 tops of weld part are provided with the arc chamfer, the sharpness of strap edges and corners has been reduced, the impaling ability of strap to utmost point ear gum and plastic-aluminum membrane CPP layer has been reduced, the possibility of the aluminium lamination contact in strap and the plastic-aluminum membrane has further been reduced, the security of soft-packing lithium cell has further been improved.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims

1. The utility model provides a lithium cell negative pole utmost point ear, includes negative pole utmost point ear piece (1), its characterized in that: utmost point auricle (1) upper and lower both sides middle part hot melt has utmost point ear glue (2), utmost point auricle (1) of negative pole includes welding part (3) and contact site (4), utmost point ear glue (2) inside still includes PP layer (6), functional layer (7) and PP layer (8) down, welding part (3) upper surface is provided with a plurality of welding wire (5).

2. The negative electrode tab for a lithium battery as claimed in claim 1, wherein: go up PP layer (6) and be located utmost point ear glue (2) outwardly, functional layer (7) are located PP layer (6) bottom, PP layer (8) are located PP layer (8) bottom down.

3. The negative electrode tab for a lithium battery as claimed in claim 1, wherein: the negative pole lug (1) is plated with nickel copper.

4. The negative electrode tab for a lithium battery as claimed in claim 1, wherein: the thicknesses of the upper PP layer (6), the functional layer (7) and the lower PP layer (8) are all 0.07 mm.

5. The negative electrode tab for a lithium battery as claimed in claim 1, wherein: the upper PP layer (6) is made of polyethylene with a melting point of 140 ℃, the functional layer (7) is made of polyvinylidene fluoride with a melting point of 170 ℃, and the lower PP layer (8) is made of polytrifluoroethylene with a melting point of 190 ℃.

6. The negative electrode tab for a lithium battery as claimed in claim 1, wherein: and an arc-shaped chamfer is arranged at the top of the welding part (3).