阅读说明：本技术 一种锂离子动力软包电池t型极耳及电池的制作方法 (Lithium ion power soft package battery T-shaped tab and manufacturing method of battery ) 是由 马华 马遂杰 暴旭 于 2020-12-14 设计创作，主要内容包括：本发明提供了一种锂离子动力软包电池T型极耳及电池的制作方法,首先通过叠片/卷绕方式,使正极片、负极片、隔膜堆叠包裹,形成芯包,再通过压紧机构将端部箔材缓慢压紧,接下来通过激光焊接把“T型”极耳与箔材焊接在一起,然后贴保护胶带,之后入壳进行热挤压封装,完成电池装配。本发明所述的锂离子动力软包电池T型极耳及电池的制作方法,简化了制作工艺,同时大大提高了电池的过流能力,在减小电池长度方向的尺寸的同时,对于电池的性能、安全均无影响,达到了提升体积能量密度的目的。(The invention provides a T-shaped tab of a lithium ion power soft package battery and a manufacturing method of the T-shaped tab of the lithium ion power soft package battery. The manufacturing method of the T-shaped tab of the lithium ion power soft package battery and the battery simplifies the manufacturing process, greatly improves the overcurrent capacity of the battery, reduces the size of the battery in the length direction, has no influence on the performance and safety of the battery, and achieves the purpose of improving the volume energy density.)

1. The utility model provides a lithium ion power laminate polymer battery T type utmost point ear which characterized in that: the tab adhesive comprises a first base material, tab adhesives and a second base material, wherein the first base material and the second base material are of a planar structure, one or more layers of tab adhesives are compounded in the middle of the front side and the back side of the first base material respectively, one end of the first base material is vertically connected with the middle of the second base material, the connecting part of the second base material with the first base material is removed from the plane of the second base material, and the rest parts are tab welding areas.

2. The T-shaped tab of the lithium-ion power soft package battery according to claim 1, characterized in that: one end of the first base material is vertically connected with the middle part of the second base material through a welding process.

3. The T-shaped tab of the lithium-ion power soft package battery according to claim 1, characterized in that: the tab glue is made of PP material.

4. The manufacturing method of the lithium ion power soft package battery is characterized by comprising the following steps:

s1, forming a core package by winding or laminating pole pieces and diaphragms required by the battery, wherein the end part of the core package is made of a foil material;

s2, stacking and compacting the foil at the end of the core bag by adopting a vertical one-step welding method, and welding the tabs on the foil of the core bag;

s3, placing the processed core packet into an aluminum plastic film packaging shell;

and S4, performing heat sealing on the core package and the to-be-packaged part of the battery to complete battery assembly.

5. The manufacturing method of the lithium ion power soft package battery according to claim 4, characterized in that: in step S2, the specific method of "vertical one-time welding" is: and the top foil is stacked and compressed along the length direction of the battery by using a compressing mechanism, the compressing degree is ensured not to damage active substances and a diaphragm area by a limiting mode, and then the tabs of the positive plate and the tabs of the negative plate are welded on the compressed foil surface by laser welding.

6. The manufacturing method of the lithium ion power soft package battery according to claim 5, characterized in that: the pressing mechanism comprises an air cylinder, a pressing block is arranged on one side of the air cylinder, and the air cylinder pushes the pressing block to stack the top foil along the length direction of the battery and slowly press the top foil.

7. The manufacturing method of the lithium ion power soft package battery according to claim 5, characterized in that: the specific limiting mode is that a limiting block is arranged at the operation end point of the air cylinder to limit the stroke of the air cylinder.

8. The manufacturing method of the lithium ion power soft package battery according to claim 5, characterized in that: and (4) after the tab in the step (S3) is welded on the foil, sticking an adhesive tape on the outside of the welding surface, and enabling the adhesive tape to wrap the edge of the tab.

Technical Field

The invention belongs to the technical field of power batteries, and particularly relates to a T-shaped tab of a lithium ion power soft package battery and a manufacturing method of the battery.

Background

The lithium ion power soft package battery is generally structurally composed of a core package, a tab, a protective adhesive tape, an aluminum plastic film and the like. Firstly, stacking and wrapping the positive plate, the negative plate and the diaphragm in a lamination/winding mode to form a core package, welding and forming the foil reserved at the end part by pre-welding (ultrasonic welding), then cutting the foil (enabling the end surface of the foil to be neat and facilitating main welding), then performing main welding (welding the lug on the foil by ultrasonic/laser), and finally performing hot extrusion packaging to complete battery assembly. The battery structure was analyzed, and the length thereof was defined as the battery body length + the soldering region length × 2+ the package region length × 2. Wherein the body length is dependent on the battery capacity/energy design; the length of the packaging area depends on the requirement of packaging strength; the length of the welding area is used for connecting the main body and the packaging area. Under the currently generally adopted process method, all connections of the welding part of the battery in the length direction are horizontal connections, and the required length space is large. For example, a VDA310 type cell has a single side weld zone of about 8mm space length and 16mm total sides. The volume of the existing battery is large, the energy storage is small, and the volume energy density of the battery is small.

Disclosure of Invention

In view of this, the invention aims to provide a T-shaped tab of a lithium ion power soft package battery, so as to solve the problems of small volume energy density and unstable overcurrent capacity of the existing battery.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

the utility model provides a lithium ion power laminate polymer battery T type utmost point ear, includes a substrate, utmost point ear glue and No. two substrates, and a substrate and No. two substrates are planar structure, and the middle part of a substrate tow sides is compound one deck or multilayer utmost point ear glue respectively, and the one end of a substrate is connected with the middle part of No. two substrates is perpendicular, detach the coupling part with a substrate on No. two substrate planes, and the rest part is utmost point ear welding area.

Furthermore, one end of the first base material is vertically connected with the middle of the second base material through a welding process.

Furthermore, the tab glue is made of PP material.

Compared with the prior art, the T-shaped tab of the lithium ion power soft package battery has the following advantages:

(1) according to the T-shaped tab of the lithium ion power soft package battery, the welding area is changed from horizontal to vertical, and the length is changed by the thickness, so that the space length of the welding area is reduced by about 5mm from one side, the length of the whole battery is reduced by about 10mm, and the volume energy density of the battery is greatly improved.

(2) The T-shaped tab of the lithium ion power soft package battery has the advantages that the area of the welding part is larger than that of the existing plane-type tab, the VDA310 battery is taken as an example, the length of the welding part is unchanged, the width can be increased from 4mm to about 8mm, the welding area can be doubled, and the overcurrent capacity of the battery is greatly improved.

The invention also aims to provide a manufacturing method of the lithium ion power soft package battery, which aims to solve the problems of large battery volume, small energy storage, small battery volume energy density and weak battery overcurrent capacity.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a manufacturing method of a lithium ion power soft package battery comprises the following steps:

s1, forming a core package by winding or laminating pole pieces and diaphragms required by the battery, wherein the end part of the core package is made of a foil material;

s2, stacking and compacting the foil at the end of the core bag by adopting a vertical one-step welding method, and welding the tabs on the foil of the core bag;

s3, placing the processed core packet into an aluminum plastic film packaging shell;

and S4, performing heat sealing on the core package and the to-be-packaged part of the battery to complete battery assembly.

Further, in step S2, the specific method of the "vertical one-time welding" includes: and the top foil is stacked and compressed along the length direction of the battery by using a compressing mechanism, the compressing degree is ensured not to damage active substances and a diaphragm area by a limiting mode, and then the positive electrode lug and the negative electrode lug are welded on the compressed foil surface by laser welding.

Furthermore, the pressing mechanism comprises an air cylinder, a pressing block is arranged on one side of the air cylinder, and the air cylinder pushes the pressing block to stack the top foil along the length direction of the battery and slowly press the top foil.

Furthermore, the specific method of the limiting mode is that a limiting block is arranged at the operation end point of the cylinder to limit the stroke of the cylinder.

Further, after the tab in step S3 is welded to the foil, an adhesive tape is attached to the outside of the welding surface, and the adhesive tape is wrapped around the edge of the tab.

Compared with the prior art, the manufacturing method of the lithium ion power soft package battery has the following advantages:

(1) according to the manufacturing method of the lithium ion power soft package battery, firstly, the positive plate, the negative plate and the diaphragm are stacked and wrapped in a lamination/winding mode to form a core package, foil materials at the end parts are slowly compressed through a compression mechanism, then T-shaped tabs and the foil materials are welded together through laser welding, then a protective adhesive tape is pasted, and then the battery is placed into a shell for hot extrusion packaging, so that the battery assembly is completed, the manufacturing process is simplified, the overcurrent capacity of the battery is greatly improved, the size of the battery in the length direction is reduced, the performance and the safety of the battery are not affected, and the purpose of improving the volume energy density is achieved.

(2) The manufacturing method of the lithium ion power soft package battery adopts a vertical one-step welding mode, improves the processing technology of the foil at the end part of the core cladding, cancels pre-welding, changes stacking and pressing into stacking and pressing, simplifies the technological process, greatly improves the working efficiency, reduces the production cost and saves social resources.

(3) According to the manufacturing method of the lithium ion power soft package battery, the adhesive tape is pasted outside the welding surface, the edges of the tabs are wrapped by the adhesive tape, the aluminum plastic film is physically isolated from the metal sheets of the positive and negative tabs, and the aluminum plastic film is effectively protected.

(4) According to the manufacturing method of the lithium ion power soft package battery, in the process of stacking and compressing the foils, a limiting mode is adopted, so that active substances (pole pieces) and diaphragm areas are not damaged, and the quality of the battery is effectively guaranteed.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic view of a tab structure in the prior art;

fig. 2 is a schematic diagram of a T-shaped tab of a lithium-ion power soft package battery according to an embodiment of the invention;

FIG. 3 is a schematic view of a vertical one-time weld according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a lithium-ion power soft package battery according to an embodiment of the invention;

fig. 5 is a cross-sectional view of a lithium-ion power soft package battery according to an embodiment of the invention;

fig. 6 is an enlarged view of a portion a in fig. 5.

Description of reference numerals:

1-substrate No. one; 2, pole lug glue; 3-substrate number two; 4-tab welding area; 5-a separator; 6, positive plate; 7-negative pole piece; 8-foil material; 9-a welding area; 10-a core pack body; 11-a housing; 12-L type utmost point ear.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used 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," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The utility model provides a lithium ion power laminate polymer battery T type utmost point ear, as shown in figure 2, including a substrate 1, utmost point ear glue 2 and No. two substrates 3, a substrate 1 and No. two substrates 3 are planar structure, the middle part of a substrate 1 tow sides compound one deck or multilayer utmost point ear glue 2 respectively, the one end of a substrate 1 is passed through welding or the middle part of butt fusion technology and is connected perpendicularly with No. two substrates 3, detach the coupling part with a substrate 1 on No. two substrates 3 planes, the remaining part is utmost point ear welding area 4. Thereby ensuring the stability and the overcurrent capacity of the whole structure.

The first substrate 1 and the second substrate 3 are metal sheets, and in one or more embodiments, the metal sheets are made of aluminum or copper nickel plating, and the thickness of the metal sheets ranges from 0.2mm to 0.6 mm.

The tab glue 2 is pp adhesive; the thickness range of the tab glue 2 is 0.1-0.2 mm, the width is 8-12 mm, and the length of the tab glue 2 is 6-10 mm larger than that of the first base material 1; the edge of the tab glue 2 is 1mm away from the edge of the first substrate 1.

As shown in fig. 1 and fig. 2, in the T-shaped tab structure, the welding area is changed from "horizontal" to "vertical" and the length is changed by thickness, the tab of the soft-package battery in the industry at present is generally "planar", as shown in fig. 1, the distance between the edge of the tab glue in the prior art and the edge of the base material is 6mm, in this embodiment, the distance between the edge of the tab glue 2 and the edge of the base material 1mm, so that the spatial length of the tab welding area 4 is reduced by about 5mm on one side, and the overall battery length is reduced by about 10mm (on one side, i.e., "positive side or negative side", and on both sides, i.e., "positive side + negative side; taking a VDA310 type battery as an example, the length is reduced from 309mm to 299mm, and the volumetric energy density is improved by about 3.2%, which is calculated as follows:

the energy density increasing ratio is E/x y 299/(E/x y 309) -1, where E is the battery energy, x is the battery thickness, and y is the battery width, the above formula is substituted with the values, i.e., x is 11, y is 100, the formula is substituted with the values, and the calculation process is: the energy density increase ratio is E/11 × 100 × 299/(E/11 × 100 × 309) -1 ≈ 3.2%.

The T-shaped tab structure of the lithium ion power soft package battery has the advantages that the area of the welding part is larger than that of the existing plane-type tab, the VDA310 type battery is taken as an example, the length of the welding part is unchanged, the width can be increased to about 8mm from 4mm, the welding area can be doubled, and the overcurrent capacity of the battery is greatly improved.

A method for manufacturing a lithium ion power soft package battery, as shown in fig. 3 to 5, includes the following steps:

s1, forming a core package by winding or laminating pole pieces and diaphragms required by the battery, wherein the end part of the core package is made of a foil material;

the specific method for winding to form the core package comprises the following steps: the negative plate 7, the diaphragm 5 and the positive plate 6 are stacked in sequence by using a winding machine, and the ending adhesive tape is pasted after the negative plate, the diaphragm and the positive plate are rotated for a certain number of turns (the number of the rotation turns is selected according to the actual requirement of the battery), so that a core package is formed, the end part of the core package is made of a foil material 8, and the positive pole lug and the negative pole lug are both in a T-shaped lug structure.

The specific method for forming the core package by the lamination comprises the following steps: the battery core package is characterized in that the battery core package is formed by stacking a diaphragm 5, a negative plate 7, a diaphragm 5, a positive plate 6, a diaphragm 5 and a negative plate 7 … … in sequence, and sticking a termination adhesive tape after a certain number of layers is achieved (the number of layers is selected according to the actual requirement of the battery), so that a core package (the end part is a positive and negative foil material), wherein a positive electrode lug and a negative electrode lug are both in a T-shaped lug structure as shown in fig. 3.

S2, stacking, pressing and welding the foils at the end part of the core bag by adopting a vertical one-step welding method;

as shown in fig. 3, the structure of the welding part is schematic, and only the negative electrode side is shown, and the positive electrode side is aluminum foil, and the structure is similar to that; in fig. 3, from top to bottom, there are sequentially a separator 5, a negative plate 7 (dark black horizontal line in the figure), a separator 5, a positive plate 6 (light horizontal line in the figure, and short in length), a separator 5, etc., and the top of each negative plate is a reserved optical foil (no active material), the right side of a plurality of foils 8 forms a welding area 9, and the specific method of "vertical one-time welding" is: with "T type" utmost point ear match, use hold-down mechanism to pile up top foil 8 along battery length direction and compress tightly to guarantee through spacing mode that the degree of compressing tightly does not harm active material and diaphragm region, later weld the utmost point ear sheetmetal (anodal utmost point ear and negative pole utmost point ear) in the foil face that compresses tightly through laser welding (once welding).

Preferably, the pressing mechanism is a cylinder and a pressing block, and the cylinder pushes the pressing block to stack the top foil 8 along the length direction of the battery and slowly press the top foil. The compact heap is non-metallic material.

Preferably, the limiting mode is that the limiting block is arranged to limit the stroke of the air cylinder, so that the compressing block stops moving after reaching the target position.

The current commonly used foil welding structure at the end part of the core cladding is 'middle symmetrical secondary welding', and the welding structure aims to ensure that a lug and a packaging surface are in the same plane when the core cladding enters a shell subsequently. During welding, the foil is pressed to the middle layer through the welding head or the pressing mechanism to be pre-welded (primary welding), and then primary welding (secondary welding) is carried out on the foil and the tab metal sheet.

The method of vertical one-time welding is adopted, the large surface of the tab and the packaging surface can be effectively ensured to be in the same plane, meanwhile, pre-welding is cancelled, one-time tab welding is reduced, foil tearing can be effectively reduced, and the stability of the over-current of the battery is greatly improved.

And S3, welding the tabs on the core cladding foil.

And welding the T-shaped lug on the core cladding foil 8 through laser welding in the lug welding area 4.

S4, pasting an adhesive tape on the outside of the welding surface, and enabling the adhesive tape to wrap the edge of the tab;

to utmost point ear edge and plastic-aluminum membrane contact position, paste the protection sticky tape outside the face of weld to wrap up utmost point ear edge, preferred, the sticky tape is the PET sticky tape, and thickness is 30 ~ 50 um. The function of protecting the aluminum-plastic film is achieved, namely the aluminum-plastic film is physically isolated from the metal sheets of the anode lug and the cathode lug.

And S5, placing the processed core package main body 10 into an aluminum plastic film packaging shell 11.

The battery shell 11 is an aluminum-plastic film packaging shell.

And S6, performing heat sealing on the core package and the to-be-packaged part of the battery to complete battery assembly.

And (2) extruding the parts to be packaged together through a heat sealing head (usually special alloy die steel or copper materials) by using packaging equipment, and maintaining at a high temperature (170-210 ℃) for several seconds to melt and bond the PP layer and the tab glue layer of the aluminum plastic film of the parts to be packaged together.

The method cancels the foil pre-welding process at the end part of the core cladding, changes the foil pre-welding process into the top foil stacking and pressing process, and directly carries out main welding with the pole lug, thereby reducing one welding procedure and simplifying the process flow.

The scheme designs a T-shaped tab and core cladding end foil welding structure and a matched manufacturing process method, and reduces the space length of a welding area on the premise of not changing a battery main body and a packaging area, so that the length of a battery is reduced, and the volume energy density of the battery is improved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.