CN114079125A - Battery cell, manufacturing method thereof, battery and electronic equipment - Google Patents

Abstract

The present disclosure provides a battery cell and a manufacturing method thereof, a battery, and an electronic device. The manufacturing method of the battery core includes: by removing the moisture in the bare battery core, performing hot pressing treatment on the bare battery core after removing the moisture, immersing the bare battery core after the hot pressing treatment in the electrolyte, and absorbing the electrolyte solution. The bare cell is subjected to injection molding, so that the surface of the bare cell inhaled with the electrolyte is covered with the injection molding material to obtain a finished cell. During the injection molding process, the amount of injection molding material can be controlled, so that the formed injection molding film for encapsulating the bare cell has a smaller size, so that the finished cell has a smaller size, which is beneficial to the structural design of the battery.

Description

Cell and method of making the same, battery, and electronic equipment

technical field

The present disclosure relates to the technical field of electronic devices, and in particular, to a battery cell and a manufacturing method thereof, a battery, and an electronic device.

Background technique

At present, the bare cell is hermetically packaged by using a prefabricated encapsulation film or an encapsulation case, so as to isolate the bare cell from the outside world. For example, the lithium-ion bare cell is hermetically packaged using a prefabricated aluminum-plastic film or aluminum case.

However, using the above method to encapsulate the bare cell, the size of the package structure is large, resulting in a large size of the finished cell, which is not conducive to the structural design of the battery.

SUMMARY OF THE INVENTION

The present disclosure provides an improved battery cell and a manufacturing method thereof, a battery, and an electronic device.

According to a first aspect of the embodiments of the present disclosure, there is provided a method for manufacturing a battery cell, the method comprising:

Remove moisture from bare cells;

Hot-pressing the bare cells after removing moisture;

Immerse the hot-pressed bare cell in the electrolyte;

Injection molding is performed on the bare cell inhaled with the electrolyte, so that the surface of the bare cell inhaled with the electrolyte is covered with an injection molding material to obtain a finished cell.

Optionally, the bare cell includes a cell body and a tab, and the tab is connected to the cell body; and performing injection molding on the bare cell inhaled with the electrolyte includes:

Injection processing is performed on the battery core body and part of the tabs close to the battery core body that have absorbed the electrolyte, so that the surface of the battery core body and the part of the tab surface are covered by the injection molding material.

Optionally, the tabs are connected to the top surface of the battery core body; the injection molding material covering the surface of the battery core body and part of the surface of the electrode tabs forms an injection molding film; wherein,

The thickness range of the injection film covering the front and back of the battery core body is 20um-130um respectively;

The thickness of the injection-molded film covering the side of the cell body is 20um-1000um;

The thickness of the injection film covering the top surface and the bottom surface of the battery core body is respectively 50um-2000um.

Optionally, the injection molding process on the bare cell that inhales the electrolyte includes:

Using a transparent injection molding material, an injection molding process is performed on the bare cell inhaling the electrolyte, so that the surface of the bare cell inhaling the electrolyte is covered by the transparent injection molding material.

Optionally, the transparent injection molding material includes at least one of the following: polymethyl methacrylate, polystyrene, polycarbonate, styrene-methyl methacrylate copolymer, polypropylene, polyethylene terephthalate glycol esters.

Optionally, the removal of moisture in the bare cell includes:

Vacuum baking is performed on the bare cell, so that the moisture content in the bare cell after vacuum baking is less than or equal to 150 ppm.

Optionally, the hot-pressing treatment of the bare cell after removing moisture includes:

The bare cell after removing moisture is subjected to hot pressing treatment in an anhydrous environment, and the conditions of the hot pressing treatment include: a hot pressing temperature range of 70°C-100°C and a hot pressing pressure range of 0.6Mpa-2.0Mpa.

Optionally, immersing the hot-pressed bare cell in the electrolyte includes:

The hot-pressed bare cell is immersed in the electrolyte, the immersion time ranges from 12h to 30h, and the immersion temperature ranges from 15°C to 45°C.

According to a second aspect of the embodiments of the present disclosure, there is provided a battery cell manufactured according to any one of the methods described in the first aspect above.

According to a third aspect of the embodiments of the present disclosure, a battery is provided, including the battery cell described in the second aspect.

According to a fourth aspect of the embodiments of the present disclosure, an electronic device is provided, including the battery described in the third aspect.

The technical solutions provided by the present disclosure have at least the following beneficial effects:

In the embodiment of the present disclosure, by removing the moisture in the bare cell, hot-pressing the bare cell after removing the moisture, immersing the bare cell after the hot-pressing treatment in the electrolyte, and immersing the bare cell in the electrolyte The injection molding process is carried out, so that the surface of the bare cell inhaled with the electrolyte is covered with the injection molding material to obtain a finished cell. During the injection molding process, the amount of injection molding material can be controlled, so that the formed injection molding film for encapsulating the bare cell has a smaller size, thereby making the finished cell have a smaller size, which is beneficial to the structural design of the battery.

Description of drawings

FIG. 1 is a flowchart of a method for manufacturing a battery cell according to an exemplary embodiment;

FIG. 2 is a schematic diagram illustrating a method for fabricating a battery cell according to an exemplary embodiment.

Detailed ways

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. Where the following description refers to the drawings, the same numerals in different drawings refer to the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present disclosure as recited in the appended claims.

The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to limit the present disclosure. Unless otherwise defined, technical or scientific terms used in this disclosure should have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. As used in this disclosure and in the claims, "first," "second," and similar terms do not denote any order, quantity, or importance, but are merely used to distinguish the various components. Likewise, "a" or "an" and the like do not denote a quantitative limitation, but rather denote the presence of at least one. Unless stated otherwise, words like "including" or "comprising" mean that the elements or items appearing before "including" or "including" encompass the elements or items listed after "including" or "including" and their equivalents, and Other elements or objects are not excluded. "Connected" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

As used in this disclosure and the appended claims, the singular forms "a," "the," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It will also be understood that the term "and/or" as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

FIG. 1 is a flowchart of a method for manufacturing a battery cell according to an exemplary embodiment. Referring to FIG. 1 , the method includes steps 101 to 104 .

In step 101, the moisture in the bare cell is removed.

There is moisture in the bare cells, and moisture will affect the use of the cells. When making cells, the moisture in the bare cells must first be removed.

In some embodiments, the bare cells may be vacuum baked to remove moisture from the bare cells.

The experimental data show that when the moisture content in the bare cell after vacuum baking is less than or equal to 150ppm, the performance of the fabricated cell is stable.

In step 102, a hot pressing process is performed on the bare cell after removing the moisture.

Some bare cells include pole pieces and separators. The purpose of hot pressing the bare cell after removing the moisture is to fully bond the pole piece and the separator in the bare cell.

In some embodiments, the bare cell after removing moisture can be subjected to hot pressing treatment in an anhydrous environment, and the conditions of the hot pressing treatment include: a hot pressing temperature range of 70°C-100°C, and a hot pressing pressure range of 0.6Mpa-2.0 Mpa.

In step 103, the hot-pressed bare cell is immersed in the electrolyte.

For a lithium-ion battery, the electrolyte includes a solvent, a solute and an additive. For example, the solvent may include at least one of the following: EC (Ethyl cellulose ethoce, ethyl cellulose), PC (Polycarbonate, polycarbonate), DMC (Dimethyl Carbonate, Dimethyl carbonate), EMC (Epoxy Molding Compound, epoxy resin molding compound); the solute may include lithium salt, such as LiPF ₆ ; the additive may include at least one of the following: FEC (Fluoroethylenecarbonate, fluoroethylene carbonate), VC ( Vinylene Carbonate, vinylene carbonate), PS (Polystyrene, polystyrene).

When making a lithium ion cell, the hot-pressed lithium ion bare cell can be immersed in a corresponding electrolyte.

In some embodiments, the hot-pressed bare cell can be immersed in the electrolyte solution, the soaking time range is 12h-30h, and the soaking temperature range is 15°C-45°C.

Using the above soaking conditions, the bare cell can absorb sufficient electrolyte.

The soaking conditions can be set according to parameters such as the type of bare cell and the type of electrolyte.

In step 104, an injection molding process is performed on the bare cell inhaled with the electrolyte, so that the surface of the bare cell inhaled with the electrolyte is covered with an injection molding material to obtain a finished cell.

After the injection molding is completed, an injection molding film is formed on the surface of the bare cell, and the bare cell is sealed and encapsulated by the injection film.

In the traditional process of using aluminum-plastic film to encapsulate lithium-ion bare cells, the aluminum-plastic film is folded in half, the lithium-ion bare cell is placed in the space formed by the folded aluminum-plastic film, and then the three sides are sealed. Fold the two sides after sealing to reduce the space occupied by the cells. Due to the structures such as tabs on the top, it is inconvenient to fold the upper sealing edge. The top sealing structure occupies a large space, which in turn leads to a large space occupied by the battery cell, which is not conducive to the structural design of the battery.

When using the method provided by the embodiment of the present disclosure to manufacture the battery cell, the amount of injection molding material can be controlled, so that the formed injection molding film for packaging the bare battery cell has a smaller size, so that the finished battery cell has a smaller size, which is beneficial to the battery structural design.

The experimental results show that, compared with the traditional process for packaging the bare cell, the use of the injection molding process in the present disclosure to package the bare cell reduces the height of the top sealing structure of the cell and reduces the top sealing of the cell The space occupied by the structure. The height of the top seal when using the traditional process for sealing is more than 2.5mm, while the height of the top seal when using the injection molding process in the embodiment of the present disclosure is less than 2mm, and the height of the top seal is significantly reduced.

The bare cell includes a pole piece and a diaphragm. After the injection molding, the diaphragm is completely adhered by the injection film, and the problem of short circuit caused by the shrinkage of the diaphragm will not occur, which improves the safety performance of the cell.

In some embodiments, the bare cell includes a cell body and a tab, and the tab is connected to the cell body. The battery core body and part of the electrode tabs close to the battery core body can be injection-molded, so that the surface of the battery core body and part of the electrode lug surface are covered by the injection molding material.

The tabs can be fixed on the cell body.

The injection mold formed of injection material can strictly seal the battery cell body and part of the tabs.

In some embodiments, the bare cell includes a cell body and a tab, and the tab is connected to the top surface of the cell body. The injection molding material covering the surface of the bare cell inhaling the electrolyte forms an injection molding film, and the thickness of the injection mold can be designed as required. The tabs can be fixed on the top surface of the cell body.

For example, the thickness of the injection film covering the front and back of the cell body is 20um-130um respectively; the thickness of the injection film covering the side of the cell body is 20um-1000um; the thickness of the injection film covering the cell body is 20um-1000um; The thickness range of the top and bottom injection films is 50um-2000um respectively.

In some embodiments, a transparent injection molding material may be used to perform injection molding treatment on the bare cell inhaled with the electrolyte, so that the surface of the bare cell inhaled with the electrolyte is covered by the transparent injection molding material.

The transparent injection molding material covering the surface of the bare cell forms a transparent injection molding film. The bare cell is sealed and packaged with a transparent injection film, so that the final product cell has a transparent appearance, and the user can directly observe the internal structure of the cell.

In some embodiments, there are many suitable transparent injection molding materials, for example, the transparent injection molding materials may include at least one of the following: polymethyl methacrylate, polystyrene, polycarbonate, styrene-methyl methacrylate Copolymer, polypropylene, polyethylene terephthalate.

The above are only examples of transparent injection molding materials, and any applicable transparent injection molding materials can be used.

Exemplarily, FIG. 2 is a schematic diagram of a method for manufacturing a battery cell according to an exemplary embodiment, and the method for manufacturing a battery cell shown in FIG. 2 includes the following steps:

In the first step, the moisture in the bare cell is removed to obtain an anhydrous bare cell.

In the second step, in anhydrous equipment or workshop, a hot-pressing mold is used to heat-press the anhydrous bare cell, so that the pole piece and the diaphragm of the anhydrous bare cell are fully fitted.

In the third step, the hot-pressed bare cell is immersed in the electrolyte, so that the bare cell absorbs the electrolyte.

The fourth step is to place the bare cell inhaled with the electrolyte in the injection molding equipment, use the injection molding material to perform injection molding on the bare cell, and encapsulate the bare cell through the formed injection film to obtain a finished cell.

In the embodiment of the present disclosure, by removing the moisture in the bare cell, hot-pressing the bare cell after removing the moisture, immersing the bare cell after the hot-pressing treatment in the electrolyte, and immersing the bare cell in the electrolyte The injection molding process is carried out, so that the surface of the bare cell inhaled with the electrolyte is covered with the injection molding material to obtain a finished cell. During the injection molding process, the amount of injection molding material can be controlled, so that the formed injection molding film for encapsulating the bare cell has a smaller size, so that the finished cell has a smaller size, which is beneficial to the structural design of the battery.

It should be noted that the accompanying drawings are used to illustrate the fabrication method of the chip, and the thickness and size of each structure are not limited.

An embodiment of the present disclosure also provides a battery cell, which is manufactured according to the method provided by the above-mentioned embodiments of the present disclosure.

The battery cell has the characteristics that the package structure occupies a small space, which is beneficial to the structural design of the battery. The diaphragm in the cell is completely adhered by the injection film, and there is no problem of short circuit caused by the internal shrinkage of the diaphragm, which improves the safety performance of the cell. When the transparent injection molding material is used for injection molding, the produced cell has a transparent encapsulation layer, which has a transparent appearance effect, and the user can directly observe the internal structure of the cell.

The embodiments of the present disclosure also provide a battery, including the battery cells provided by the above-mentioned embodiments of the present disclosure.

Based on the advantages of the cell, the battery made of the cell also has many advantages.

Specifically, the battery cell provided by the embodiment of the present disclosure has the advantages of a small size occupied by the packaging structure, so the battery made of the battery cell has the advantages of large design space, and various structural designs can be carried out; the battery cell provided by the embodiment of the present disclosure has the advantages of It has the advantages of high safety performance, so the battery made of the battery cell has the advantages of high safety performance and long service life.

The embodiments of the present disclosure also provide an electronic device, including the batteries provided by the above-mentioned embodiments of the present disclosure.

There are many advantages to batteries based on them, as do electronic devices that include them.

There are many kinds of electronic devices, such as mobile phones, tablet computers, wearable devices, etc.

Other embodiments of the present disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common general knowledge or techniques in the technical field not disclosed by this disclosure . The specification and examples are to be regarded as exemplary only, with the true scope and spirit of the disclosure being indicated by the following claims.

It is to be understood that the present disclosure is not limited to the precise structures described above and illustrated in the accompanying drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims (11)

1. a manufacturing method of electric core, is characterized in that, described method comprises: Remove moisture from bare cells; Hot-pressing the bare cells after removing moisture; Immerse the hot-pressed bare cell in the electrolyte; Injection molding is performed on the bare cell inhaled with the electrolyte, so that the surface of the bare cell inhaled with the electrolyte is covered with an injection molding material to obtain a finished cell. 2 . The manufacturing method according to claim 1 , wherein the bare cell comprises a cell body and a tab, and the tab is connected to the cell body; the pair of inhaling the electrolyte solution Bare cells are injection-molded, including: Perform injection molding on the battery cell body and part of the tabs near the cell body that absorb the electrolyte, so that the surface of the cell body and the part of the tab surface are covered with the injection molding material. 3 . The manufacturing method according to claim 2 , wherein the tab is connected to the top surface of the battery core body; the injection molding covering the surface of the battery core body and the part of the electrode lug surface is 3 . The material forms an injection-molded film; wherein, The thickness range of the injection film covering the front and back of the battery core body is 20um-130um respectively; The thickness of the injection film covering the side surface of the battery core body is 20um-1000um; The thickness of the injection film covering the top surface and the bottom surface of the cell body is respectively 50um-2000um. 4. The manufacturing method according to claim 1 , wherein the injection molding process is performed on the bare cells sucked into the electrolyte, comprising: Using a transparent injection molding material, an injection molding process is performed on the bare cell inhaling the electrolyte, so that the surface of the bare cell inhaling the electrolyte is covered by the transparent injection molding material. 5. The manufacturing method according to claim 4, wherein the transparent injection molding material comprises at least one of the following: polymethyl methacrylate, polystyrene, polycarbonate, styrene-methyl methacrylate Copolymer, polypropylene, polyethylene terephthalate. 6. The manufacturing method according to claim 1, wherein the removing moisture in the bare cell comprises: Vacuum baking is performed on the bare cell, so that the moisture content in the bare cell after vacuum baking is less than or equal to 150 ppm. 7. The manufacturing method according to claim 1, wherein the hot-pressing treatment of the bare cell after removing moisture comprises: The bare cell after removing moisture is subjected to hot pressing treatment in an anhydrous environment, and the conditions of the hot pressing treatment include: a hot pressing temperature range of 70°C-100°C, and a hot pressing pressure range of 0.6Mpa-2.0Mpa. 8. The manufacturing method according to claim 1, wherein the step of immersing the hot-pressed bare cell in the electrolyte comprises: The hot-pressed bare cell is immersed in the electrolyte, the immersion time ranges from 12h to 30h, and the immersion temperature ranges from 15°C to 45°C. 9 . A battery cell, characterized in that, the battery core is manufactured according to the method of any one of claims 1-8. 10. A battery, characterized by comprising the battery cell of claim 9. 11. An electronic device, comprising the battery of claim 10.

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