阅读说明：本技术 一种软包锂离子电池制作工艺 (Manufacturing process of soft package lithium ion battery ) 是由 冯宇 韩冰 郑开元 纪荣进 郑明清 陈杰 杨山 李载波 于 2019-09-06 设计创作，主要内容包括：本发明提供一种软包锂离子电池制作工艺,包括以下步骤：S1,裸电芯完成卷绕后,在干燥无氧的环境下,将裸电芯放入电解液池中至电解液液平面达到裸电芯的极耳胶位置,浸润时间为10s～2h,其中,电解液的温度维持在20～150℃；S2,将浸润好的裸电芯取出,烘干至裸电芯不再滴电解液且电解液含量满足预设值,烘干温度为20～150℃；S3,烘干完毕后,将裸电芯放入铝塑膜中,先进行顶封,然后同时进行侧封和气袋边封边,完成封装。相比于现有技术,本发明直接将裸电芯置于电解液池中浸润并烘干,且侧封和气袋边封边同时进行,通过改善现有的工艺,大大缩短了静置时间,简化了工序流程,提高了生产效率。(The invention provides a manufacturing process of a soft package lithium ion battery, which comprises the following steps: s1, after the winding of the bare cell is completed, the bare cell is placed into an electrolyte tank in a dry and oxygen-free environment until the electrolyte liquid plane reaches the tab glue position of the bare cell, and the soaking time is 10S-2 h, wherein the temperature of the electrolyte is maintained at 20-150 ℃; s2, taking out the soaked bare cell, and drying until the bare cell does not drip electrolyte any more and the electrolyte content meets a preset value, wherein the drying temperature is 20-150 ℃; s3, after drying, putting the bare cell into the aluminum-plastic film, carrying out top sealing, and then simultaneously carrying out side sealing and edge sealing of the air bag edge to complete packaging. Compared with the prior art, the method has the advantages that the bare cell is directly placed in the electrolyte tank for soaking and drying, the side sealing and the edge sealing of the air bag are simultaneously carried out, the standing time is greatly shortened, the process flow is simplified and the production efficiency is improved by improving the prior art.)

1. A manufacturing process of a soft package lithium ion battery is characterized by comprising the following steps:

s1, after the winding of the bare cell is completed, the bare cell is placed into an electrolyte tank in a dry and oxygen-free environment until the electrolyte liquid plane reaches the tab glue position of the bare cell, and the soaking time is 10S-2 h, wherein the temperature of the electrolyte is maintained at 20-150 ℃;

s2, taking out the soaked bare cell, and drying until the bare cell does not drip electrolyte any more and the electrolyte content meets a preset value, wherein the drying temperature is 20-150 ℃;

s3, after drying, putting the bare cell into the aluminum-plastic film, carrying out top sealing, and then simultaneously carrying out side sealing and edge sealing of the air bag edge to complete packaging.

2. The manufacturing process of the soft package lithium ion battery according to claim 1, wherein in the step S1, the temperature of the electrolyte is maintained at 60-150 ℃.

3. The manufacturing process of the soft package lithium ion battery of claim 1, wherein in the step S1, the bare cell is pre-vacuum baked before being placed in the electrolyte cell.

4. The manufacturing process of the soft package lithium ion battery according to claim 3, wherein the vacuum degree of the vacuum baking is-80 to-100 kPa.

5. The manufacturing process of the soft package lithium ion battery according to claim 1, wherein in the step S2, the drying temperature is 20-80 ℃.

6. The process for manufacturing the soft-packaged lithium ion battery according to claim 1, wherein the steps S2 and S3 are performed in a dry oxygen-free environment.

7. The manufacturing process of the soft package lithium ion battery according to claim 1, wherein in the step S2, the content of the electrolyte meets a preset value of 0-50 g.

8. The manufacturing process of the soft package lithium ion battery according to claim 1, wherein in the step S1, the speed of the bare cell immersed in the electrolyte cell is controlled to be 1-20 cm/S.

9. The manufacturing process of the soft package lithium ion battery according to claim 1 or 6, wherein the dry and oxygen-free environment is an oxygen-free environment with a dew point temperature of less than or equal to-35 ℃.

10. The manufacturing process of the soft package lithium ion battery according to claim 1, wherein after the step of S3 is completed, the manufacturing process further comprises the following steps: and placing the packaged bare cell into formation equipment for formation, then vacuumizing for secondary packaging, and finally performing capacity grading test to complete the manufacture of the battery.

Technical Field

The invention relates to the field of lithium batteries, in particular to a manufacturing process of a soft package lithium ion battery.

Background

The lithium ion battery as a novel secondary battery has the advantages of large energy density and power density, high working voltage, light weight, small volume, long cycle life, good safety, environmental protection and the like, and has wide application prospect in the aspects of portable electric appliances, electric tools, large-scale energy storage, electric traffic power supplies and the like. Lithium ion batteries are mainly classified into cylindrical batteries, square batteries, and pouch batteries according to their shapes, and the cylindrical batteries and the square batteries are also called hard-shell batteries. Compared with a hard-shell battery, the soft-package battery has the characteristics of flexible design, lighter weight, small internal resistance, difficult explosion, more cycle times, high energy density and the like, and therefore the soft-package battery occupies the market in a higher proportion in a short period.

The soft package battery mainly comprises the following process flows: 1) stirring, coating, rolling and cutting; 2) sheet making and winding; 3) forming an aluminum plastic film and packaging by a roll core; 4) a top side sealing process; 5) liquid injection and pre-sealing; 6) a formation step; 7) secondary sealing; 8) and (4) carrying out subsequent procedures such as capacity grading and the like. In the traditional production process, after the battery core top side sealing process is finished, vacuum baking is performed in advance before liquid injection, water content is removed, and then the liquid injection process is performed. However, the standing time is long, so that the production efficiency of the battery is low, too much time is not consumed in standing in actual production, and the short standing time causes insufficient absorption of the electrolyte, so that the performance and the service life of the battery are affected.

In view of the above, it is necessary to provide a technical solution to the above problems.

Disclosure of Invention

The invention aims to: the manufacturing process of the soft package lithium ion battery is provided, the time for soaking the battery core with the electrolyte after the battery core is injected with the electrolyte is shortened by improving the liquid injection process, the process flow is simplified, the packaging time is shortened, and the production efficiency is further improved.

In order to achieve the purpose, the invention adopts the following technical scheme:

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

s1, after the winding of the bare cell is completed, the bare cell is placed into an electrolyte tank in a dry and oxygen-free environment until the electrolyte liquid plane reaches the tab glue position of the bare cell, and the soaking time is 10S-2 h, wherein the temperature of the electrolyte is maintained at 20-150 ℃;

s2, taking out the soaked bare cell, and drying until the bare cell does not drip electrolyte any more and the electrolyte content meets a preset value, wherein the drying temperature is 20-150 ℃;

s3, after drying, putting the bare cell into the aluminum-plastic film, carrying out top sealing, and then simultaneously carrying out side sealing and edge sealing of the air bag edge to complete packaging.

According to the invention, the naked electric core is directly arranged in the electrolyte tank, so that the electrolyte can infiltrate any position of the electric core from the periphery, the naked electric core can fully absorb the electrolyte content which meets the actual requirement of the electrolyte in a short time, and meanwhile, the temperature of the electrolyte can be controlled to be maintained in a high-temperature state, so that the step of high-temperature standing is also completed when the electric core is infiltrated, the subsequent step of high-temperature standing is omitted, and the standing time is greatly shortened. Then the soaked naked electric core is taken out, the naked electric core can be dried by utilizing hot air, the drying is also equivalent to the promotion of the naked electric core to absorb electrolyte again, and the time for the electric core to stand at normal temperature is further shortened. In addition, because naked electric core has accomplished the process of absorbing electrolyte, when putting into the plastic-aluminum membrane naked electric core, can carry out the side seal simultaneously and the bag limit banding, simplified process flow, shortened the encapsulation time. The invention greatly shortens the production time of the battery and improves the production efficiency by improving each procedure.

Preferably, in the step S1, the temperature of the electrolyte is maintained at 60 to 150 ℃. Temperature control in usable temperature controller will electrolyte is between 60 ~ 150 ℃, can promote naked electric core to the absorption of electrolyte and can not influence the performance of electrolyte under this high temperature condition, has also been equivalent to the high temperature process of stewing of accomplishing naked electric core simultaneously, has shortened process time greatly.

Preferably, in the step S1, before the bare cell is placed in the electrolyte bath, vacuum baking is performed in advance. Before naked electric core liquid injection, toast in advance, get rid of remaining moisture in the naked electric core, keep the inside of naked electric core dry, prevent that remaining moisture from influencing the performance and the subsequent formation process of electrolyte.

Preferably, the vacuum degree of the vacuum baking is-80 to-100 kPa.

Preferably, in the step S2, the drying temperature is 20-80 ℃. After naked electric core accomplished the infiltration, a part electrolyte can adhere and leave the electrolyte pond thereupon in naked electric core, and naked electric core has accomplished most electrolyte absorption this moment, and usable hot-blast will be unnecessary electrolyte and blow off, makes it break away from naked electric core, and simultaneously, hot-blast temperature can promote naked electric core and further absorb electrolyte, adopts the hot-blast activity that also can reduce electrolyte effectively of the temperature low point, improves the lock liquid ability of naked electric core. The lower drying temperature is preferably maintained at 20-80 ℃.

Preferably, both steps S2 and S3 are performed in a dry, oxygen-free environment. Because the electrolyte is exposed on the periphery, the electrolyte can be polluted if the peripheral environment of the naked electric core is not strictly controlled in the infiltration process, and the electrolyte infiltrated into the naked electric core can contain a plurality of impurities. In subsequent technological processes such as formation and the like, the requirement on the internal water content is high, and the moisture can promote substances in the electrolyte to react, so that the generation of an SEI film is influenced. Therefore, it is important to ensure the infiltration of the bare cell and the oxygen-free drying environment of the drying process.

Preferably, in the step S2, the content of the electrolyte meets a preset value of 0-50 g. The preset value of the electrolyte can be adjusted according to the model of the battery cell, and the injection amount of different battery cells is different.

Preferably, in the step S1, the speed of the bare cell immersed in the electrolyte tank is controlled to be 1-20 cm/S. When the naked electric core enters the electrolyte tank, the falling speed of the naked electric core needs to be controlled, and the naked electric core enters the electrolyte tank slowly at a constant speed. Falling speed is too fast so that naked electric core does not have to reach the environment in the adaptation electrolyte and just directly soaks wherein, may lead to it to absorb electrolyte not good and inhomogeneous, and slow whereabouts helps naked electric core from interior to exterior fully to absorb electrolyte. More preferably, the speed of the naked battery cell entering the electrolyte tank is 1-10 cm/s.

Preferably, the dry oxygen-free environment is an oxygen-free environment with the dew point temperature of less than or equal to-35 ℃. When the dew point temperature is less than or equal to minus 35 ℃, the water content of the air is low, the air is kept to be infiltrated in the environment, the quality of the electrolyte and the infiltration effect cannot be influenced by the peripheral environment, and the stability of the infiltration process of the bare cell is ensured.

Preferably, after the step of S3 is completed, the method further includes the following steps: and placing the packaged bare cell into formation equipment for formation, then vacuumizing for secondary packaging, and finally performing capacity grading test to complete the manufacture of the battery.

The invention has the beneficial effects that: the invention provides a manufacturing process of a soft package lithium ion battery, which comprises the following steps: s1, after the winding of the bare cell is completed, the bare cell is placed into an electrolyte tank in a dry and oxygen-free environment until the electrolyte liquid plane reaches the tab glue position of the bare cell, and the soaking time is 10S-2 h, wherein the temperature of the electrolyte is maintained at 20-150 ℃; s2, taking out the soaked bare cell, and drying until the bare cell does not drip electrolyte any more and the electrolyte content meets a preset value, wherein the drying temperature is 20-150 ℃; s3, after drying, putting the bare cell into the aluminum-plastic film, carrying out top sealing, and then simultaneously carrying out side sealing and edge sealing of the air bag edge to complete packaging. Compared with the prior art, the bare cell is directly placed in the electrolyte tank for soaking and drying, the subsequent high-temperature standing process is finished by controlling the temperature environment in the electrolyte tank, the normal-temperature standing time is shortened, the side sealing and the edge sealing of the air bag are simultaneously carried out, the process flow is simplified, and the packaging time is shortened. Therefore, the invention greatly shortens the standing time, simplifies the process flow and improves the production efficiency by improving the prior process.

Drawings

FIG. 1 is a process flow diagram of example 1 of the present invention.

Detailed Description

In order to make the technical solutions and advantages of the present invention clearer, the present invention and its advantages will be described in further detail below with reference to the following detailed description and the accompanying drawings, but the embodiments of the present invention are not limited thereto.