Specification
Title of Invention: Electrode assembly and manufacturing method thereof
technical field
[One]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0154664 on November 27, 2019, and all contents disclosed in the documents of the Korean patent applications are incorporated as a part of this specification.
[2]
The present invention relates to an electrode assembly and a method for manufacturing the same, and more particularly, to an electrode assembly manufacturing method and manufacturing method that can solve problems occurring when the fixing tape is attached by eliminating the conventional fixing tape. It relates to an electrode assembly that can be manufactured.
[3]
background
[4]
A battery for storing electrical energy may be generally divided into a primary battery and a secondary battery. A primary battery is a disposable consumable battery, whereas a secondary battery is a rechargeable battery manufactured using a material in which oxidation and reduction processes between an electric current and a substance are repeatable. That is, when the reduction reaction of the material is performed by the current, the power is charged, and when the oxidation reaction is performed on the material, the power is discharged. Such charge-discharge can be repeatedly performed.
[5]
Among various types of secondary batteries, lithium secondary batteries are generally manufactured by mounting an electrode assembly in which a positive electrode, a separator, and an anode are stacked in a case, and lithium ions are produced from the lithium metal oxide of the positive electrode to the negative electrode. As the process of intercalation and deintercalation is repeated, charging and discharging of the lithium secondary battery proceeds.
[6]
In the electrode assembly, a predetermined number of unit cells in which a negative electrode, a separator, and a positive electrode are stacked in a predetermined order are stacked or a positive electrode, a separator, and a negative electrode are repeatedly stacked one by one to form one electrode assembly. In addition, the electrode assembly is accommodated in a case such as a cylindrical can or a prismatic pouch and manufactured as a secondary battery.
[7]
On the other hand, as a method of manufacturing the electrode assembly, a winding type manufactured by laminating a separator between the negative electrode and the positive electrode and then winding, cutting to have the required width and length, cutting the negative electrode and the positive electrode, and then the negative electrode and the separator , a stack-and-fold type, which is manufactured by stacking anodes so that they are repeated, and a stack-and-fold type, which are manufactured by placing unit cells side by side on a folding separator and then folding from one side, etc. are known.
[8]
Of the double, stacked electrode assembly, as shown in FIG. 1A in which the conventional manufacturing process is simplified and shown, the positive electrode 2, the separator 1, and the negative electrode 3 are stacked by a predetermined number to form a unit cell (10). After being manufactured, the unit cells 10 are stacked by a predetermined number to manufacture the electrode assembly 100 . For reference, in the electrode assembly shown in FIG. 1A, a monocell in which a separator/anode/separator/cathode is stacked from the bottom is manufactured as a unit cell 10 and a plurality of stacked, separator membranes/ The half-cell 20 stacked in the electrode (cathode or anode)/separator order is placed on the uppermost layer.
[9]
And, when the unit cells 10 are stacked by a predetermined number, the fixing tape 200 is wound around the electrode assembly 100 so that the electrode assembly 100 is fixed (or the side surfaces are on the upper and lower surfaces) to be bound) to bind the unit cells 10 .
[10]
However, in the structure for binding through the fixing tape 200 in this way, as shown in FIG. 1b , the folding and lifting phenomenon of the separator in the conventional electrode assembly structure occurs, the fixing tape 200 is adhered. There may be a problem in that the end of the separation membrane 1 is folded or lifted by the pressure applied when it is made.
[11]
The folding and lifting of the separator 1 may cause contact between the negative electrode 3 and the positive electrode 2 to cause a short circuit.
[12]
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[13]
Accordingly, the main object of the present invention is to provide an electrode assembly capable of eliminating the process of additionally adhering a fixing tape after lamination of the electrode assembly is completed, and a method for manufacturing the same, so as to solve the above-described problems.
[14]
means of solving the problem
[15]
The electrode assembly of the present invention for achieving the object as described above, in the electrode assembly in which the negative electrode, the separator, and the positive electrode are repeatedly stacked, arranged to cover any one of the side surfaces formed by stacking the negative electrode, the separator, and the positive electrode and a film to be used, wherein the film is adhered to the side formed by laminating a negative electrode, a separator, and a positive electrode by an adhesive.
[16]
The film is disposed on each of two opposite sides of the side surfaces formed by stacking the negative electrode, the separator, and the positive electrode.
[17]
The adhesive may be any one selected from a resin having fluidity, a thermosetting adhesive, and a UV curing resin.
[18]
In this case, the film is formed to be longer than the height of the side formed by laminating the negative electrode, the separator, and the positive electrode, and both ends extend from the side and have a folded structure to be adhered to the lowermost layer and the uppermost layer.
[19]
In addition, the present invention additionally provides a manufacturing method capable of manufacturing the electrode assembly having the above configuration.
[20]
The manufacturing method according to the present invention, in the manufacturing method of an electrode assembly in which a negative electrode, a separator, and a positive electrode are repeatedly stacked, a unit cell manufacturing step (S10) of manufacturing a unit cell having a predetermined stacking structure of a negative electrode, a separator, and a positive electrode ; A film insertion step of inserting the film into the mold (S20); a unit cell stacking step of stacking the unit cells in the mold (S30); and an adhesive application step (S40) of applying an adhesive between the unit cells and the film stacked in the mold; It is characterized in that the cell lamination step (S30) and the adhesive application step (40) are repeated.
[21]
In the unit cell manufacturing step (S10), a unit cell is manufactured so that a junction is formed by bonding the ends of the separator to each other, and in the adhesive application step (S40), an adhesive is applied between the junctions of each of the unit cells placed next to each other above and below each other. Apply for injection.
[22]
And, in the unit cell manufacturing step (S10), the unit cell is manufactured as a monocell stacked in the order of separator/cathode/separator/anode or monocell stacked in the order of separator/anode/separator/cathode from the bottom. In addition, the half-cell stacked in the separator/cathode/separator sequence from the bottom or the half-cell stacked in the separator/positive electrode/separator sequence is manufactured as a unit cell separately from the monocell. And, while the unit cell stacking step (S30) is repeatedly performed, the stacking is made with mono cells, when the unit cell stacking step (S30) is finally performed, the stacking is made with half cells.
[23]
The adhesive applied in the adhesive application step (S40) may be any one selected from a resin having fluidity, a thermosetting adhesive, and a UV curing resin.
[24]
When the adhesive is a thermosetting adhesive, the method further includes a heating step (S41) of curing the thermosetting adhesive by applying heat to the mold.
[25]
In addition, when the adhesive is made of a UV curing resin, it further includes a UV irradiation step (S42) of penetrating the film and irradiating ultraviolet rays to the portion to which the adhesive is applied.
[26]
On the other hand, when inserting the film into the mold in the film inserting step (S20), the lower end of the film may be inserted in a folded state such that when the first unit cell is stacked, it is stacked under the lowermost layer of the unit cell. In addition, when the lamination of the last unit cell is completed, the upper end of the film is folded so as to be laminated on the uppermost surface of the uppermost unit cell (S50); may further include.
[27]
Effects of the Invention
[28]
Since the electrode assembly of the present invention having the above technical characteristics is attached to the side of the electrode assembly instead of the fixing tape (because the pressure generated when the fixing tape is attached is removed), it occurs in the conventional structure It is possible to prevent the separation membrane from being folded or lifted.
[29]
In the present invention, since the adhesion with the film is made separately for each unit cell, the adhesion between the unit cell and the film can be made more stably even if no pressure is applied. In particular, since a junction is formed at the end of the unit cell, the movement of individual unit cells is fixed, so the alignment of the entire electrode assembly can also be improved.
[30]
In addition, in the present invention, the upper and lower ends of the film are folded to cover the uppermost and lowermost layers of the electrode assembly, thereby preventing the adhesive from flowing down before curing is made.
[31]
Brief description of the drawing
[32]
1A is a simplified view of a conventional electrode assembly manufacturing process;
[33]
1B is a view showing a state in which folding and lifting phenomena of a separator occur in a conventional electrode assembly structure;
[34]
Figure 2 is a flow chart of the electrode assembly manufacturing method of the present invention.
[35]
3 is a view showing a state in which a negative electrode, a separator, and a positive electrode are laminated in the unit cell manufacturing step to be manufactured as a unit cell;
[36]
4A is a view showing a cross-sectional view (a) of a mold in the method for manufacturing an electrode assembly of the present invention and a state in which a film is attached to the mold (b);
[37]
Figure 4b is a state in which the unit cell is seated between the films in the form shown in Fig. 4a (c), a state in which the glue gun applies an adhesive between the seated unit cell and the film (d) and the next unit cell is added A figure additionally showing the state in which the glue gun applies the adhesive between the unit cell and the film seated with the seated unit (e).
[38]
FIG. 4c is a state in which the top of the film is folded after the uppermost unit cell is seated in the form shown in FIG. 4b (f) and a state in which UV is irradiated into the form to cure the applied adhesive (g) is additionally shown drawn drawing.
[39]
5 is a plan view, a front view, and a left side view of an electrode assembly manufactured by the method of manufacturing an electrode assembly of the present invention;
[40]
Modes for carrying out the invention
[41]
Hereinafter, based on the accompanying drawings, the present invention will be described in detail so that those of ordinary skill in the art can easily implement it. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein.
[42]
In order to clearly describe the present invention, parts irrelevant to the description are omitted, and the same reference numerals are assigned to the same or similar elements throughout the specification.
[43]
Also, the real nameThe terms or words used in the specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and that the inventor may appropriately define the concept of the term in order to best describe his invention. Based on the principle, it should be interpreted as meaning and concept consistent with the technical idea of ​​the present invention.
[44]
The present invention relates to an electrode assembly in which a negative electrode 3, a separator 1, and a positive electrode 2 are repeatedly stacked, and a manufacturing method thereof. Explain.
[45]
[46]
first embodiment
[47]
[48]
The present invention provides a method for manufacturing an electrode assembly as a first embodiment. As described in FIG. 2 showing the sequence of the electrode solvy body manufacturing method according to the present invention, the manufacturing method according to this embodiment is a unit cell manufacturing step (S10), a film insertion step (S20), a unit cell stacking step (S30) ), an adhesive application step (S40), and a film folding step (S50).
[49]
In the unit cell manufacturing step (S10), a unit cell 10 having a predetermined stacked structure of the negative electrode 3, the separator 1, and the positive electrode 2 is manufactured, but the ends of the separator 1 are bonded to each other to form a junction ( 1a) is prepared to form.
[50]
That is, as shown in FIG. 3 showing that the cathode 3, the separator 1, and the anode 2 are stacked to form a unit cell 10, a monocell having a predetermined stacking structure and A half cell is prepared as a unit cell (10). The monocell has a structure in which a separator (1)/anode (2)/separator (1)/cathode (3) is stacked in order from the bottom as shown, or a separator (1)/cathode (3)/ from the bottom The separator (1)/anode (2) may have a stacked structure in the order. In addition, a half cell in which the uppermost electrode (anode or cathode) is removed from the monocell is additionally provided. The half-cell has a structure in which the separator (1)/cathode (3)/separator (1) is stacked in order from the bottom so that the separator (1) is placed on the uppermost layer after lamination of the monocell is completed, or the separator (1)/ It has a structure in which the anode (2)/separator (1) are stacked in the order. Therefore, since the stacking of the half cells is made after the stacking of the monocells is completed, the electrode assembly stacked according to the present invention has a structure in which the separator 1 is placed on the lowermost layer and the uppermost layer.
[51]
On the other hand, the unit cell 10 made of the mono-cell and the half-cell has a structure in which the separator 1 has a larger area than the positive electrode 2 and the negative electrode 3 and the ends protrude from both sides as shown. . In this unit cell manufacturing step (S10), the ends of the separation membranes 1 are bonded to each other to form a junction 1a. The bonding portion 1a does not necessarily have to be formed at all of the protruding ends of the separator 1, but is preferably formed at the ends facing the film 30 when the unit cells 10 are stacked.
[52]
4a to 4c, a cross-sectional view of the form (a), a film attached to the form (b), a unit cell seated between the films (c), a glue gun between the seated unit cell and the film The state of applying this adhesive (d), the next unit cell is additionally seated, and the state that the glue gun applies the adhesive between the seated unit cell and the film (e) are respectively shown.
[53]
Referring to FIGS. 4A to 4C , in the film inserting step S20 , the films 30 are disposed on inner peripheral surfaces of both sides facing each other within the form M. The mold (M) is manufactured to a size that allows the stacking of the unit cells 10 therebetween in a state in which the film 30 is disposed, and has sufficient rigidity.
[54]
The mold (M) may be configured such that the internal space in which the stacking of the unit cells 10 is made to form a hexahedron, a gripper for transporting and stacking the unit cells 10 when the unit cells 10 are stacked; One side or both sides on which the film 30 is not disposed may be provided in an open state so that interference does not occur when the like) is operated.
[55]
And, in the mold (M), between the film 30 and the unit cell 10, the adhesive (A) is placed in a state of being temporarily fixed to the inner circumferential surface of the mold (M) so as to maintain a vertically erected state before being applied. can be That is, tongs, a holder, etc. for temporarily fixing the film 30 may be installed on the form (M), or the film 30 has a weak adhesive force on the surface before being disposed in the form (M). The arrangement may be made in a state in which the adhesive is applied. As for the means for temporarily fixing the film 30 , other known methods may be applied if the film 30 can be easily separated from the inner circumferential surface of the mold M after the production of the electrode assembly is completed.
[56]
In addition, when the adhesive (A) is applied between the film (30) and the unit cell (10), the mold (M) is the glue gun (G) in the vertical direction so that the entry of the glue gun (G) is possible. A slit (not shown) or the like may be formed, or it may have a structure in which the glue gun (G) is slidably mounted in the form (M).
[57]
On the other hand, when inserting the film 30 into the mold M in the film inserting step (S20), the lower end of the film 30 is the lowermost surface of the unit cell 10 when the first unit cells are stacked down. It is preferable to be inserted in a folded state so as to be laminated. The folded part of the film 30 is provided for the purpose of preventing the adhesive (A) from flowing out before it is cured after being applied in the mold (M), and the length of the folded part depends on the amount and state of the adhesive (A) can be determined according to
[58]
In the state where the film 30 is disposed in the mold M and the operation of the glue gun G is prepared, the next unit cell stacking step (S30) is performed. In the unit cell stacking step (S30), the unit cells 10 are stacked in the mold M at a fixed position between the two films 30 . At this time, the unit cell 10 is a mono-cell as described above, but is laminated so that the separator 1 is placed on the lower side.
[59]
Then, an adhesive application step (S40) of applying the adhesive (A) between the unit cells (10) and the film (30) stacked in the mold (M) is performed.
[60]
In this embodiment, two films 30 are inserted so as to abut one by one on both side wall surfaces facing each other in the form M, so that the adhesive A is applied at the same time on each of both side walls of the form M.
[61]
After the film insertion step (S20), the unit cell stacking step (S30) and the adhesive application step (40) are repeated until the stacking of the predetermined unit cells 10 is completed. At this time, the stacking of the unit cells 10 placed on the uppermost layer in the film inserting step (S20) is made of half-cell stacking instead of the mono-cell. When the adhesive application of the half cell is completed (when lamination of the last unit cell is completed), the upper end of the film 30 is folded to be laminated on the uppermost layer surface of the uppermost unit cell 10. A folding step (S50) is performed. The top of the folded film 30 is in close contact with the separator 1 placed on the uppermost layer in the unit cell 10 of the uppermost layer.
[62]
On the other hand, the adhesive (A) used in this embodiment has non-conductivity in order to prevent short circuit, but the type is not limited. Therefore, in the state where the folding step (S50) is completed, curing may not be completed depending on the type of the adhesive (A) injected between the joint portions 1a of each of the unit cells 10 placed next to each other.
[63]
That is, the adhesive (A) applied in this embodiment may be any one selected from a resin having fluidity, a thermosetting adhesive, and a UV curing resin.
[64]
The present invention further provides additional steps for curing the adhesive (A) so that the electrode assembly can be removed from the mold (M) in a state where the adhesion of the film (30) is completed.
[65]
For example, when the adhesive (A) is a thermosetting adhesive, it may further include a heating step (S41) of curing the thermosetting adhesive by applying heat to the mold (M).
[66]
On the other hand, when the adhesive (A) is made of a UV-curing resin, it may further include a UV irradiation step (S42) of penetrating the film 30 and irradiating ultraviolet rays to the portion to which the adhesive is applied.
[67]
In addition, if the film 30 is also made of a non-conductive material, the selection is not limited, but it may be made of a polymer material such as PET (polyethylene terephthalate), which has poor adhesion and good chemical resistance.
[68]
For reference, in the adhesive application step (S40), the glue gun (G) may have a heating function to improve the fluidity of the adhesive, and the heating temperature and spray pressure, etc., depend on the thickness and material of the film 30 or the bonding portion 1a. ) may vary depending on the relative position and size of the At this time, the mold (M) is configured such that the end of the glue gun (G) enters or the glue gun (G) is built-in as described above, and in a state stacked on the mold, a heating step (S41) or a UV irradiation step (S42) Since is made, the adhesion of the film 30 is made in the form (M).
[69]
In addition, the mold (M) is made of a material capable of heat conduction depending on whether the heating step (S41) or the UV irradiation step (S42) is in progress, or a structure that can be irradiated with ultraviolet (UV) to the inside (for example, , a structure made of a transparent material or a structure in which holes through which ultraviolet rays can enter are perforated).
[70]
[71]
second embodiment
[72]
[73]
The present invention provides an electrode assembly that can be manufactured by the manufacturing method according to the first embodiment as a second embodiment.
[74]
The electrode assembly provided in this embodiment is an electrode assembly in which a negative electrode 3, a separator 1, and a positive electrode 2 are repeatedly stacked, and formed by stacking a negative electrode 3, a separator 1, and a positive electrode 2 It includes a film 30 disposed to cover any one of the side surfaces, wherein the film 30 is formed by laminating a negative electrode 3, a separator 1, and a positive electrode 2 by an adhesive (A). It is characterized in that it is attached to the
[75]
That is, referring to FIG. 5 showing a plan view, a front view, and a left side view of an electrode assembly manufactured by the method for manufacturing an electrode assembly of the present invention, the negative electrode 3 and the positive electrode 2 according to the present invention are protruded to one side. It has a negative electrode tab 3a and a positive electrode tab 2a, respectively. The positive electrode tab 2a and the negative electrode tab 3a are configured to protrude opposite to each other, and each side of the electrode assembly including two sides forming a right angle with the side from which the positive electrode tab 2a and the negative electrode tab 3a protrude On Film (30)It has an attached configuration. At this time, the upper end 30a of the film 30 is folded to cover the uppermost surface of the portion where the negative electrode 3, the positive electrode 2, and the separator 1 are stacked, and the lower end 30b of the film 30 ) is folded so as to cover the lowermost surface of the portion where the cathode 3, the anode 2, and the separator 1 are stacked.
[76]
[77]
In the electrode assembly of the present invention having the above technical characteristics, the film 30 is attached to the side of the electrode assembly instead of the fixing tape (because the pressure generated when the fixing tape is attached is removed), the conventional structure It is possible to prevent the folding or lifting of the separation membrane that occurred in the
[78]
In the present invention, since the adhesion with the film 30 is made separately for each unit cell 10, the adhesion between the unit cell 10 and the film 30 can be made more stably even if no pressure is applied. In particular, since the unit cell 10 has a junction portion 1a formed at an end thereof, the movement of the individual unit cells 10 is fixed, so that the alignment of the entire electrode assembly can also be improved.
[79]
In addition, in the present invention, the upper and lower ends of the film 30 are folded to cover the uppermost and lowermost layers of the electrode assembly, thereby preventing the adhesive (A) from flowing down before curing is made.
[80]
In the above, although the present invention has been described with reference to limited examples and drawings, the present invention is not limited thereto, and it is described below with the technical idea of ​​the present invention by those of ordinary skill in the art to which the present invention pertains. Various implementations are possible within the scope of equivalents of the claims to be made.

Claims

[Claim 1]
In an electrode assembly in which a negative electrode, a separator, and a positive electrode are repeatedly stacked, a film disposed to cover any one of the side surfaces formed by stacking a negative electrode, a separator, and a positive electrode; , an electrode assembly, characterized in that the anode is laminated and adhered to the formed side.
[Claim 2]
According to claim 1, wherein the film is an electrode assembly, characterized in that the electrode assembly, characterized in that disposed on each of the two opposite sides of the side formed by stacking the negative electrode, the separator, and the positive electrode.
[Claim 3]
The electrode assembly according to claim 1, wherein the adhesive is any one selected from a resin having fluidity, a thermosetting adhesive, and a UV curing resin.
[Claim 4]
The electrode assembly according to claim 1, wherein the film is formed to be longer than the height of the side surface formed by laminating the negative electrode, the separator, and the positive electrode, and both ends extend from the side and are folded to adhere to the lowermost layer and the uppermost layer. .
[Claim 5]
A method for manufacturing an electrode assembly in which a negative electrode, a separator, and a positive electrode are repeatedly stacked, comprising: a unit cell manufacturing step (S10) of manufacturing a unit cell in which a negative electrode, a separator, and a positive electrode have a predetermined stacking structure; A film insertion step of inserting the film into the mold (S20); a unit cell stacking step of stacking the unit cells in the mold (S30); and an adhesive application step (S40) of applying an adhesive between the unit cells and the film stacked in the mold; A method of manufacturing an electrode assembly, characterized in that the cell lamination step (S30) and the adhesive application step (40) are repeated.
[Claim 6]
[Claim 6] The method of claim 5, wherein in the unit cell manufacturing step (S10), the unit cells are manufactured by bonding the ends of the separator to form a junction, and in the adhesive application step (S40), each of the unit cells placed next to each other above and below each other Method of manufacturing an electrode assembly, characterized in that the coating is applied so that the adhesive is injected between the joints.
[Claim 7]
The method according to claim 6, wherein in the unit cell manufacturing step (S10), a monocell stacked in the order of separator/cathode/separator/anode from the bottom or monocells stacked in the order of separator/anode/separator/cathode to manufacture unit cells A method of manufacturing an electrode assembly, characterized in that.
[Claim 8]
The method according to claim 7, wherein in the unit cell manufacturing step (S10), the half cells stacked in the separator/cathode/separator order from the bottom or the half cells stacked in the separator/anode/separator order are manufactured as unit cells separately from the mono cells. And, while the unit cell stacking step (S30) is repeatedly performed, lamination is made with mono cells, characterized in that when the unit cell stacking step (S30) is finally performed, the stacking is made with half cells A method of manufacturing an electrode assembly.
[Claim 9]
The method of claim 5, wherein the adhesive applied in the adhesive application step (S40) is any one selected from a resin having fluidity, a thermosetting adhesive, and a UV curing resin.
[Claim 10]
The electrode assembly according to claim 9, wherein the adhesive applied in the adhesive application step (S40) is a thermosetting adhesive, and further comprising a heating step (S41) of curing the thermosetting adhesive by applying heat to the mold. manufacturing method.
[Claim 11]
The method according to claim 9, wherein the adhesive applied in the adhesive application step (S40) is made of a UV curing resin, and further comprising a UV irradiation step (S42) of penetrating the film and irradiating ultraviolet rays to the portion to which the adhesive is applied. A method of manufacturing an electrode assembly, characterized in that.
[Claim 12]
The method according to claim 5, wherein when the film is inserted into the mold in the film inserting step (S20), the lower end of the film is inserted in a folded state so as to be stacked under the lowermost layer of the unit cell when the first unit cell is stacked. A method of manufacturing an electrode assembly, characterized in that.
[Claim 13]
13. The method of claim 12, further comprising a folding step (S50) in which the upper end of the film is folded to be stacked on the uppermost surface of the uppermost unit cell when lamination of the last unit cell is completed.