阅读说明：本技术 一种用于Degas封装的上封头、下封头及用其提高Degas封装可靠性的方法 (Upper end socket and lower end socket for Degas packaging and method for improving Degas packaging reliability by using upper end socket and lower end socket ) 是由 谢水军 张衡 孟旭 刘宝来 郑义 陶胜 于 2021-06-24 设计创作，主要内容包括：本发明属于电池制造技术技术领域,公开了一种用于Degas封装的上封头、下封头,包括：上封头和下封头均设有槽口,上封头槽口设有蘑菇型头部,下封头槽口设有T字型头部；蘑菇型头部、T字型头部均由软性材料制成。同时公开了用设有蘑菇型头部的上封头和设有T字型头部的下封头提高Degas封装可靠性的方法,包括：在封装过程中通过上封头和下封头挤压去除两层铝塑复合膜间的封装区域内的游离电解液,再通过抽真空、加温、加压完成Degas封装。这种设有蘑菇型头部的上封头和设有T字型头部的下封头配合使用能够将封装区的电解液有效去除,保证封装的可靠性。(The invention belongs to the technical field of battery manufacturing, and discloses an upper end socket and a lower end socket for Degas packaging, which comprise: the upper sealing head and the lower sealing head are both provided with notches, the notches of the upper sealing head are provided with mushroom-shaped heads, and the notches of the lower sealing head are provided with T-shaped heads; the mushroom-shaped head and the T-shaped head are made of soft materials. Simultaneously, the method for improving the Degas packaging reliability by using the upper end socket with the mushroom-shaped head and the lower end socket with the T-shaped head is disclosed, and comprises the following steps: and in the packaging process, the free electrolyte in the packaging area between the two layers of aluminum-plastic composite films is removed through the extrusion of the upper end enclosure and the lower end enclosure, and the Degas packaging is completed through the steps of vacuumizing, heating and pressurizing. The upper end socket with the mushroom-shaped head and the lower end socket with the T-shaped head are matched to use, so that electrolyte in a packaging area can be effectively removed, and the packaging reliability is guaranteed.)

1. An upper end enclosure and a lower end enclosure for Degas packaging are characterized in that the upper end enclosure and the lower end enclosure are both provided with notches, the notches of the upper end enclosure are provided with mushroom-shaped heads, and the notches of the lower end enclosure are provided with T-shaped heads; the mushroom-shaped head and the T-shaped head are both made of soft materials.

2. A closure according to claim 1, wherein the upper and lower closure slots are located in the middle of the end surface and are one of T-shaped and vertical strips.

3. A closure according to claim 1, wherein the mushroom head has a square bottom, a height equal to the depth of the upper closure groove, a width equal to the width of the upper closure groove, a semicircular top, and a diameter of the arc surface equal to the width of the upper closure.

4. A closure according to claim 1, wherein the height of the bottom of the T-shaped head is the same as the depth of the slot of the lower closure, the width of the bottom is the same as the width of the slot of the lower closure, and the width of the top is the same as the width of the lower closure.

5. A closure according to claim 1, wherein the soft material comprises one or more of silicone, rubber.

6. A seal head according to claim 1, characterized in that the connection part of the mushroom-shaped head and the seal head is fixedly connected with the outer side of the connection part of the T-shaped head and the seal head through a high temperature resistant adhesive tape.

7. A method for improving the reliability of Degas packaging by using the upper head and the lower head as claimed in claim 1, wherein the method comprises: and in the packaging process, the free electrolyte in the packaging area between the two layers of aluminum-plastic composite films is removed through the extrusion of the upper end enclosure and the lower end enclosure, and the Degas packaging is completed through the steps of vacuumizing, heating and pressurizing.

8. The method according to claim 7, wherein the Degas pumping packaging vacuum degree is 75-100KPa under negative pressure, the pressure of the pressing plate is 0.1-0.6MPa, and the vacuum pumping holding time is 2-8 s.

9. The method as claimed in claim 7, wherein the heating temperature is 140-200 ℃, the sealing pressure is 0.1-0.6MPa, and the sealing time is 2-8 s.

10. The method of claim 7, wherein the aluminum-plastic composite film comprises one or more of a PP aluminum-plastic film and a PE aluminum-plastic film.

Technical Field

The invention belongs to the technical field of battery manufacturing, and particularly relates to an upper end socket and a lower end socket for Degas packaging and a method for improving the Degas packaging reliability by using the upper end socket and the lower end socket.

Background

The lithium ion battery has the characteristics of diversified sizes, light weight and the like, the aluminum-plastic composite film is mainly used as a shell for packaging, and the safety performance and the service performance of the battery core are directly determined by the good hot-press packaging of the aluminum-plastic composite film. And the qualified difficulty of hot-press packaging is obviously higher than that of top sealing and side sealing due to the unique characteristic that the Degas packaging after liquid injection is influenced by electrolyte during packaging. How to ensure that the package is acceptable in the presence of the electrolyte is a challenge to the industry.

The existing packaging technology mainly has the following problems: at present, Degas packaging is mostly carried out by using upper and lower flat seal heads with the width of 4-5mm, free electrolyte in a packaging area is pumped out by vacuumizing, and under the condition that the amount of free electrolyte is large, the electrolyte is accumulated in the packaging area to absorb the heat of the seal heads, so that the uniform fusion of two layers of aluminum-plastic composite films is influenced, finally, the poor molten glue or the insufficient packaging strength after packaging is caused, and the leakage safety accident is formed.

Disclosure of Invention

The invention aims to provide a method for improving the reliability of a Degas package aiming at the problems in the prior art.

The purpose of the invention can be realized by the following technical scheme:

the upper end enclosure and the lower end enclosure are both provided with notches, the notches of the upper end enclosure and the lower end enclosure are provided with mushroom-shaped heads, the notches of the lower end enclosure are provided with T-shaped heads, and the mushroom-shaped heads and the T-shaped heads are made of soft materials.

Preferably, the upper end socket slot and the lower end socket slot are positioned in the middle of the end face and are in one of a T shape and a vertical strip shape.

Further preferably, the depth of the groove is 1-5mm, and the width of the groove is 1-3 mm.

Preferably, the bottom 4 of the mushroom-shaped head is square, the height of the mushroom-shaped head is equal to the depth of the groove of the upper sealing head, the width of the mushroom-shaped head is equal to the width of the groove of the upper sealing head, the top 3 of the mushroom-shaped head is semicircular, and the diameter of the cambered surface of the mushroom-shaped head is equal to the width of the upper sealing head.

Preferably, the height of the bottom of the T-shaped head is the same as the depth of the groove of the lower end socket, the width of the bottom 6 is the same as the width of the groove of the lower end socket, and the width of the top 5 is the same as the width of the lower end socket.

Preferably, the soft material comprises one or more of silica gel and rubber.

The arc-shaped soft material can be matched with the plane soft material, and free electrolyte in the packaging area is effectively extruded from the point and the surface, so that the packaging is not influenced by the electrolyte.

Preferably, the joint of the mushroom-shaped head and the end enclosure is fixedly connected with the outer side of the joint of the T-shaped head and the end enclosure through a high-temperature-resistant adhesive tape.

A method for improving the reliability of a Degas package by using an upper head and a lower head comprises the following steps: and in the packaging process, the free electrolyte in the packaging area between the two layers of aluminum-plastic composite films is removed through the extrusion of the upper end enclosure and the lower end enclosure, and the Degas packaging is completed through the steps of vacuumizing, heating and pressurizing.

Preferably, the vacuum degree of the Degas pumping and packaging is 75-100KPa under negative pressure, the pressure of a pressing plate is 0-0.6MPa, and the vacuumizing retention time is 2-8 s.

Preferably, the heating temperature is 140-.

Preferably, the aluminum-plastic composite film comprises one or more of a PP aluminum-plastic film and a PE aluminum-plastic film.

Compared with the prior art, the invention has the following beneficial effects:

1. the mushroom-shaped head soft material of the upper end socket and the T-shaped head soft material of the lower end socket are matched and extruded, electrolyte in a packaging area is effectively extruded from a point and a surface, and then the Degas packaging is completed by heating and pressurizing, so that the melting of the two layers of aluminum-plastic composite films after packaging is not influenced by the electrolyte, and the packaging quality is also ensured.

2. Through setting up the replaceable soft material head, effectively reduce the use wearing and tearing of metal head, show improvement metal head life, reduce the processing requirement and the cost of head to soft material head can easily be replaced.

Drawings

Fig. 1 is a schematic view of an upper metal head.

Fig. 2 is a schematic view of the lower metal head.

Fig. 3 is a schematic view of a header mushroom type head.

Fig. 4 is a schematic view of a T-shaped head of the lower head.

Fig. 5 is a schematic view of the extrusion of the upper head and the lower head.

In the figure, 1, an upper end enclosure; 2. a lower end enclosure; 3. a mushroom-type head; 31. the top of the mushroom-type head; 32. the bottom of a mushroom-type head; 4. a T-shaped head; 41. the top of the T-shaped head; 42. the bottom of the T-shaped head.

Detailed Description

The following are specific examples of the present invention and further describe the technical solutions of the present invention, but the present invention is not limited to these examples.

Example 1

The middle parts of the end surfaces of the upper end socket 1 and the lower end socket 2 are provided with vertical strip-shaped grooves, the groove depth is 4mm, and the groove width is 2 mm; establish mushroom type head 3 at the head, its top 31 semicircle silica gel diameters are 4mm, establish the T type head 4 at the low head, and the width of the square silica gel of its top 41 is 4mm, and the height is 2 mm.

The packaging material is a PP aluminum plastic film with the thickness of 76mm, the vacuum degree of Degas air extraction packaging is set to be 85KPa under negative pressure, the pressure of a pressing plate is 0.4MPa, and the vacuum extraction retention time is set to be 5 s; the temperature of the upper and lower end socket thermocouples is set to be 160 ℃, the packaging pressure is set to be 0.5MPa, and the packaging time is set to be 6 s. In the automatic mode, actions such as air bag puncture, vacuum pumping, pressing of the cell main body by the pressing plate, hot-pressing and packaging are completed in the sealed cavity, and the extrusion process of the upper end enclosure and the lower end enclosure is shown in fig. 5.

Observing the seal melting glue to be uniform milky white; no swelling at 60 ℃ and 92% relative humidity; the seal is permeated by using a penetrant, and is still kept for 4 hours at the normal temperature of 25 ℃ without penetrating, so that the reliability of the package is shown.

Example 2

The middle parts of the end surfaces of the upper end socket and the lower end socket are provided with vertical strip-shaped grooves, the groove depth is 4mm, and the groove width is 3 mm; the semicircular silica gel diameter of the mushroom-shaped head part arranged on the upper end socket is 4mm, the width of the square silica gel arranged on the top of the T-shaped head part of the lower end socket is 4mm, and the height of the square silica gel is 2 mm.

The packaging material is a PE aluminum plastic film with the thickness of 88mm, the vacuum degree of Degas air extraction packaging is set to be 95KPa under negative pressure, the pressure of a pressing plate is 0.3MPa, and the vacuum extraction retention time is set to be 8 s; the temperature of the upper and lower end socket thermocouples is set to 170 ℃, the packaging pressure is set to 0.4MPa, and the packaging time is set to 6 s. In an automatic mode, actions such as air bag puncture, vacuum pumping, pressing of the cell main body by the pressing plate, hot-pressing packaging and the like are completed in the sealed cavity.

Observing the seal melting glue to be uniform milky white; no swelling at 63 ℃ and 96% relative humidity; the seal is not penetrated by penetrating agent and stands still for 4 hours at the normal temperature of 29 ℃, and the reliability of the package is shown.

Comparative example 1

The upper and lower sealing heads are metal plane sealing heads covered with Teflon adhesive tapes.

The packaging material is a PE aluminum plastic film with the thickness of 86mm, the vacuum degree of Degas air extraction packaging is set to be 95KPa under negative pressure, the pressure of a pressing plate is 0.4MPa, and the vacuum extraction retention time is set to be 4 s; the temperature of the upper and lower end socket thermocouples is set to be 160 ℃, the packaging pressure is set to be 0.5MPa, and the packaging time is set to be 6 s. In an automatic mode, actions such as air bag puncture, vacuum pumping, pressing of the cell main body by the pressing plate, hot-pressing packaging and the like are completed in the sealed cavity.

Observing seal melten gel, wherein local melten gel is missing or is in a pockmark shape; when the temperature is 60 ℃ and the relative humidity is 90%, the individual battery core bulges; the seal is permeated by using a penetrant, and is kept still for 4 hours at the normal temperature of 25 ℃, so that the penetrability of individual cells exists.

Comparative example 2

The upper and lower sealing heads are metal plane sealing heads covered with Teflon adhesive tapes.

The packaging material is a PP aluminum plastic film with the thickness of 87mm, the vacuum degree of Degas air extraction packaging is set to be negative pressure 80KPa, the pressure of a pressing plate is 0.5MPa, and the vacuum extraction retention time is set to be 6 s; the temperature of the upper and lower end socket thermocouples is set to 170 ℃, the packaging pressure is set to 0.4MPa, and the packaging time is set to 7 s. In an automatic mode, actions such as air bag puncture, vacuum pumping, pressing of a pressing plate to extrude the cell main body, hot-pressing packaging and the like are completed in the sealed cavity, and the amount of free electrolyte in the cell is reduced to 0.3 g.

Observing the seal melting glue to be uniform milky white; when the temperature is 62 ℃ and the relative humidity is 91%, individual battery cell bulges; the seal is permeated by a penetrant, and is kept still for 4 hours at the normal temperature of 24 ℃, so that the penetrability of individual cells exists.

Comparative example 3

The upper and lower sealing heads are metal plane sealing heads covered with Teflon adhesive tapes.

The packaging material is a PP aluminum plastic film with the thickness of 91mm, the vacuum degree of Degas air extraction packaging is set to be negative pressure 90KPa, the pressure of a pressing plate is 0.3MPa, and the vacuum extraction retention time is set to be 5 s; the heating temperature of the upper and lower end socket thermocouples is set to 220 ℃, the packaging pressure is set to be 0.4MPa, and the packaging time is set to be 6 s. In an automatic mode, actions such as air bag puncture, vacuum pumping, pressing of the cell main body by the pressing plate, hot-pressing packaging and the like are completed in the sealed cavity.

Observing the seal melting glue to be uniform milky white; no swelling at 63 ℃ and 94% relative humidity; the seal is permeated by using a penetrant, and is kept still for 4 hours at the normal temperature of 26 ℃, so that the penetrability of individual cells exists.

In conclusion, the upper end socket with the mushroom-shaped head and the lower end socket with the T-shaped head are matched for use, so that the electrolyte in the packaging area can be effectively removed, and the packaging reliability is ensured; and the soft material that can conveniently replace has reduced the wearing and tearing of metal head, has reduced the cost. Lowering the amount of free electrolyte inside the cell to lower values or raising the packaging temperature can slightly increase the reliability of the packaging, but the overall result is not as good as in the embodiments within the scope of protection of the present invention.

The technical scope of the invention claimed by the embodiments of the present application is not exhaustive, and new technical solutions formed by equivalent replacement of single or multiple technical features in the technical solutions of the embodiments are also within the scope of the invention claimed by the present application; in all the embodiments of the present invention, which are listed or not listed, each parameter in the same embodiment only represents an example (i.e., a feasible embodiment) of the technical solution, and there is no strict matching and limiting relationship between the parameters, wherein the parameters may be replaced with each other without departing from the axiom and the requirements of the present invention, unless otherwise specified.