Title of invention: pressurization jig including magnet and battery module including same
Technical field
[One]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0014016 filed on February 1, 2019, and all contents disclosed in the documents of the Korean patent application are included as part of this specification.
[2]
The present invention relates to a pressing jig including a magnet and a battery module including the same.
Background
[3]
In general, a cell refers to an electrochemical cell that supplies an electric potential between at least one set of terminals and a device including a set of cells. The terminals of the cell may be electrically connected to a direct current load, for example, to provide energy or voltage to the load. Cells include dry cells, wet cells (eg, lead-acid cells), and other devices that convert commonly chemically available electromotive force into electric current.
[4]
Among these batteries, a secondary battery is manufactured by making an electrode assembly having a three-layer structure of a positive electrode plate/separator/cathode plate or a multilayer structure of five or more layers of a positive plate/separator/cathode plate/separator/anode plate, and accommodating such an electrode assembly in a pouch. The secondary battery is also referred to as a pouch-type secondary battery.
[5]
The characteristic of the secondary battery is that it can be recharged after use, and its capacity is not infinite, but it is possible to repeatedly use the same battery by performing the discharge treatment in reverse to a certain extent. In other words, a secondary battery is a battery capable of charging and discharging, unlike a primary battery that cannot be charged, and is widely used in the field of advanced electronic devices such as mobile phones, notebook computers, and camcorders. In particular, lithium secondary batteries have a higher energy density per unit weight compared to other secondary batteries such as conventional lead storage batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries, and thus increase in use. It is an active trend.
[6]
A lithium-based oxide is used as a positive electrode active material used in such a lithium secondary battery, and a carbon material is used as a negative electrode active material. A predetermined area by stacking a positive electrode plate with a positive electrode tab on a positive electrode current collector on which a positive electrode active material was formed using such an active material, a negative electrode plate provided with a negative electrode tab on the negative electrode current collector on which the negative electrode active material was formed, and a separator interposed between the positive electrode plate and the negative electrode plate. In the case of manufacturing an electrode assembly of, receiving such an electrode assembly in a pouch, injecting an electrolyte into the pouch through an opening on one side of the pouch, sealing the opening, charging and discharging, an aging process, and a degas process The manufacturing of the pouch-type battery cell is completed by performing an activation process including a process of removing a part of the pouch surface where gas is collected.
[7]
On the other hand, when the pouch of the pouch-type battery cell is filled with an electrolyte, both sides of the pouch itself are convex to the outside, so a pressurizing operation of pressing both sides of the pouch of the battery cell is required to increase the capacity of the battery. In other words, since the capacity of the battery can be increased only when the electrolyte solution filled in the pouch of the battery cell is spread evenly, it is necessary to pressurize the battery cell to spread the electrolyte evenly.
[8]
In addition, the pressurization makes the gap between the components of the electrode assembly inside the battery cell as compact as possible to increase the capacity of the battery, and it is possible to suppress the growth of lithium dendrites generated in the subsequent charging and discharging process. It also becomes excellent. This is particularly noticeable in lithium metal batteries using lithium metal as a negative electrode active material.
[9]
On the other hand, in order to pressurize the battery cells, the battery cells have been pressurized by using a pressing jig.
[10]
However, there is a limit to pressurization simply by mechanical pressure, and thus, there has been a limit to improving capacity and life performance.
[11]
Accordingly, there is a high need for a technology capable of exhibiting more excellent performance by increasing the pressing force by pressing the battery cells more effectively.
Detailed description of the invention
Technical challenge
[12]
An object of the present invention is to solve the problems of the prior art and technical problems that have been requested from the past.
[13]
An object of the present invention is to further improve the pressing force applied to the battery cells by including a magnet in a pressing jig for applying mechanical pressing force to the battery cells, and to improve battery performance by providing a more uniform pressing force.
Means of solving the task
[14]
Therefore, the present invention,
[15]
As a pressurizing jig that performs pressurization of the battery cell,
[16]
A plurality of pressure plates positioned at the outermost edge of the plurality of battery cells and between them to separate a space in which the plurality of battery cells are contained, and pressurize the plurality of battery cells; And pressing frames connecting the pressing plates to each other at the upper and lower portions of the plurality of pressing plates, and
[17]
All of the plurality of pressing plates, or the remaining pressing plates excluding only one pressing plate located at the outermost side of one side, can be moved in a pressing direction and a horizontal direction while being connected to the pressing frames,
[18]
A pair of pressing plates positioned at the outermost sides of the plurality of pressing plates are provided with a pressing jig including magnets having opposite polarities facing each other.
[19]
Hereinafter, the present invention will be described in more detail to aid understanding of the present invention.
[20]
The terms or words used in the specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventor may appropriately define the concept of terms in order to describe his own invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of ​​the present invention based on the principle that there is.
[21]
The terms used in the present specification are only used to describe exemplary embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.
[22]
In the present specification, terms such as "comprises", "includes" or "have" are intended to designate the presence of implemented features, numbers, steps, components, or a combination thereof, and one or more other features or It is to be understood that the possibility of the presence or addition of numbers, steps, elements, or combinations thereof is not preliminarily excluded.
[23]
According to the present invention, the pressing unit simultaneously serves to pressurize while supporting a plurality of battery cells embedded in the pressing jig.
[24]
With such a structure, in the present invention, the pressing jig can minimize the volume while mechanically pressing the plurality of battery cells.
[25]
On the contrary, if a support member is to be included separately from the pressure plates, the volume increases by that amount, which is not preferable.
[26]
Therefore, in the pressurization part, the plurality of pressurization plates must be present at the outermost so that the battery cells are not exposed to the outside while separating the space in which the battery cells are built, the number of the plurality of pressurization plates is the number of the plurality of battery cells. Always one more than
[27]
In addition, in order to perform the above function, at least some of the pressing plates must be movable, and in this case, movable pressing plates among the pressing plates may be determined according to the position of the driving unit moving the pressing unit.
[28]
For example, when the driving unit is formed to press a pair of pressing plates located on both sides and located at the outermost side in a direction facing each other, all of the pressing plates may be movable in the pressing direction and the horizontal direction.
[29]
On the other hand, when the driving unit is located on one side and formed to press the battery cells in one direction, the outermost pressing plate on the opposite side of the driving unit to be transmitted must be fixed. Therefore, in this case, while all the pressing plates are movable, one outermost pressing plate may be arbitrarily fixed, or the outermost pressing plate on one side may be in a non-movable form.
[30]
Accordingly, in the pressing jig according to the present invention, all of the plurality of pressing plates may be in a form in which the remaining pressing plates except for one pressing plate positioned at the outermost side of one side can be moved.
[31]
In addition, the pressing plates may have a plate shape corresponding to the shape of the battery cells without bending so that a uniform pressing force can be applied to the entire battery cells, and may be made of a material having a certain rigidity and a predetermined thickness.
[32]
Meanwhile, the pressing unit further includes pressing frames that support and connect the plurality of pressing plates while being able to contain a plurality of battery cells.
[33]
The pressing frame may have a structure connecting the pressing plates at the upper and lower portions of the plurality of pressing plates in order to solidify the plurality of pressing plates.
[34]
Therefore, when the battery cells are embedded, the pressing frames according to the present invention are parallel to the upper pressing frame and the upper pressing frame located in a direction in which the electrode terminals of the battery cells protrude, and in a direction opposite to the direction in which the electrode terminals protrude. It may include a lower pressure frame located.
[35]
By including the upper base frame and the lower base frame as described above, the pressure plates can receive force from the driving unit as a whole.
[36]
Here, a direction in which the electrode terminal protrudes is referred to as an upper direction and a direction opposite to the direction in which the electrode terminal protrudes is referred to as a lower direction in the upper and lower portions.
[37]
The shape of the upper pressing frame and the lower pressing frame is not limited as long as it has a structure connecting the pressing plates, but the upper pressing frame is located in the direction in which the electrode terminals of the battery cells to be built are protruding, so that the electrical connection between the electrode terminals afterwards It is more preferable that the portion where the electrode terminals are located has an open shape so that it can be performed smoothly.
[38]
Accordingly, the upper pressurizing frame may be formed in a shape of two or more bars having a structure parallel to each other, and electrode terminals of battery cells to be built later may be exposed between these bars.
[39]
On the other hand, since the lower pressurizing frame needs to form a space in which battery cells can be embedded together with the pressurizing plates, the lower pressurizing frame may have a single plate shape so that the battery cells can be stably seated.
[40]
Meanwhile, as described above, according to the present invention, since the pressing jig has a compact structure in a state in which the battery cells are embedded thereafter, the battery cells must be pressed between a pair of pressing plates located at the outermost sides of both sides. They must be able to move in a pressing direction and a horizontal direction while being connected to the pressing frames.
[41]
Accordingly, a specific member or device for allowing the pressing plates to move may be formed in the pressing frames, and as an example, a structure such as a rail may be formed. Of course, it is not limited as long as it is a structure capable of moving and fixing the pressure plates.
[42]
The driving unit is not limited as long as it is a structure capable of moving the pressing unit described above. For example, the driving unit may be present on one side or both sides, and may be a structure connected to a pressure plate existing at the outermost side of one or both sides, and the shape thereof is in the form of a pressure plate or a pressure rod, but is not limited.
[43]
As described above, if the driving part is formed on one side, the outermost pressing plate opposite to the direction in which the driving part is formed should be fixed, and if the driving part is formed on both sides, all the pressing plates may be movable.
[44]
On the other hand, according to the present invention, the pressing jig includes a magnet on the outermost pressing plates with opposite polarities facing each other, and mechanical pressure according to the movement of the pressing unit by the driving unit with respect to the battery cell, and separately, It has a structure that can simultaneously pressurize battery cells even by the magnetism of magnets having different polarities.
[45]
Specifically, according to the present invention, a pair of pressing plates positioned at the outermost sides of the plurality of pressing plates may include magnets having opposite polarities facing each other.
[46]
In addition, a magnet may be included in all of the pressing plates in a form having opposite polarities facing each other.
[47]
That is, it may be included only at the outermost sides of both sides, or may be included in all the pressing plates as a whole, but at this time, the magnets may be included in a form in which opposite polarities face each other.
[48]
Here, the facing form means that when one side is included in the form of N/S, the other side is included in the form of N/S, so that S on one side and N on the other side face each other.
[49]
Accordingly, since the attractive force by the magnet of the opposite polarity can be applied to the plurality of battery cells built between the press plates including the magnet, the pressurization by the magnet can be simultaneously performed.
[50]
In this way, the inventors of the present application are able to increase the pressing force on the battery cells more than when the pressurization by magnetic in addition to the mechanical pressurization is carried out at the same time. It was confirmed that more excellent battery performance was exhibited by means of the above.
[51]
In this case, the shape in which the magnet is included is not limited, and for example, some or all of the pressure plates may be made of magnets, and the magnets may be attached to the inner surface or both surfaces of the pressure plates facing the battery cells. Specifically, the outermost pressing plates may be attached to the inner surfaces of the pressing plates, and the pressing plates in the middle position may be attached to both sides.
[52]
At this time, the area including the magnet is not limited, but in order to apply a pressing force to the entire battery cell so that there is no deviation of the pressing force inside the battery cell, it is preferable that the area is equal to or larger than the area of ​​the battery cell to be built. .
[53]
In this structure, the magnetic pressing force may be determined by Gaussian of magnets of different polarities included in the pressing plates.
[54]
When the magnet is included as described above, even a little magnetic pressure is generated, but the magnetic pressure is performed at the same time as the mechanical pressure. It is preferably Gauss or more, or more preferably 3000 Gauss or more. And, it is preferable that it is 7000 gauss or less, 6000 gauss or less, or 5000 gauss or less, and it is because the Gauss range of the magnet that can be manufactured by the present technology is at most 7000 gauss, and easily 5000 gauss or less.
[55]
Meanwhile, the present invention also provides a battery module in which a plurality of battery cells are embedded in the pressing jig and inserted into the module case in a pressed state.
[56]
That is, the pressing jig is inserted into the battery module as a whole, so that the pressing of the battery cell can be continued even while the battery module is operating.
[57]
At this time, the battery cells built in the pressurization jig may have a thin plate shape, and the type thereof is not limited, but in detail, it may be a pouch-type battery cell that requires more steady pressurization due to a large amount of external deformation during operation of the battery. .
[58]
In addition, the type is not limited, for example, a lithium ion battery, a lithium polymer battery, a lithium ion polymer battery, a lithium metal ion battery, a lithium free ion battery, etc., but charging and discharging of the battery cell Due to the large volume change, the growth of lithium dendrites is mainly a problem.Si and Si, which can effectively solve this problem by pressing the battery cells more strongly through additional pressurization through a magnet at the same time as the mechanical pressurization by the pressurization unit / Or a lithium ion battery, a lithium polymer battery, a lithium ion polymer battery in which Sn is applied to the negative electrode, or a lithium metal ion battery using lithium metal as the negative electrode active material, or a lithium-free ( free) an ion battery, and more specifically, a lithium metal ion battery.
[59]
In addition, the module case is a plate or box shape capable of completely blocking a pressure jig in which a plurality of battery cells are built in by mechanically combining the lower module case in the form of a box with an open upper part and the lower module case. It may include an upper module case.
[60]
The lower module case and the upper module case are not limited to the above shape as long as the press jig in which the battery cells are embedded can be completely blocked from the outside, and various structures are of course possible.
[61]
In this way, the reason why the module case blocks the pressure jig from the outside is to solve a problem in which the magnet included in the pressure jig may affect other configurations of the device in which the battery module is mounted thereafter.
[62]
Accordingly, the module case may further include a shielding material or a shielding film having a magnetic shielding function to shield the magnetism of the magnet included in the pressing jig.
[63]
Here, when the module case is made of a shielding material, the shielding material is not limited as long as it has a magnetic shielding function, and may be, for example, a polyester-based material. In this case, the module case may be manufactured in the form of a conventionally known module case having a certain thickness so as to have a certain rigidity.
[64]
Meanwhile, when the module case includes a shielding film, the shielding film may be attached to the entire inner or outer surface of the module case. Of course, of course, it may be attached to both surfaces of the inner and outer surfaces of the module case.
[65]
In this case, the shape of the shielding film is not limited, but since it is a form attached to the module case, it is not necessary to have rigidity, and it is preferable that the shielding film is in a light fiber form so as to minimize an increase in weight of the entire module case. Do.
[66]
Specifically, the shielding film is not limited as long as it is a material having a shielding function, and may be, for example, a nonwoven fabric made of a polyester-based material.
[67]
Further, the shielding film may have a structure in which a conductive material is partially or entirely coated on a nonwoven fabric made of a polymer having a shielding function, for example, a polyester-based material as described above.
[68]
In the case where the shielding film is attached to the module case, the module case may be made of a conventionally known material, and thus a detailed description thereof will be omitted.
[69]
In the battery module structured as described above, since the mechanical pressurization and magnetic pressurization of the battery cells are continued even during operation of the battery, the effect of suppressing lithium dendrites can be sustained, thereby improving the life performance of the battery cells. In addition, safety can be ensured because it is possible to prevent the influence of magnets on other components that may occur.
[70]
Meanwhile, other components of the module case, for example, detailed structures such as an external terminal, may include all of the conventionally known components.
Brief description of the drawing
[71]
1 is a plan view of a pressing jig showing a state before being pressed in a state in which a battery cell is embedded according to an embodiment of the present invention;
[72]
2 is a plan view of a pressing jig showing a state in which the battery cells are pressed in FIG. 1;
[73]
Figure 3 is a top view of Figure 2;
[74]
4 is a perspective view of a module case according to an embodiment of the present invention;
[75]
5 is a top view showing a battery cell pressurizing jig inserted into the lower module case of FIG. 4;
[76]
6 is a plan view of a pressing jig showing a pressed state in a state in which a battery cell is embedded according to another embodiment of the present invention;
[77]
7 is a plan view of a pressing jig showing a pressed state in a state in which a battery cell is embedded according to an embodiment of the present invention.
Mode for carrying out the invention
[78]
Hereinafter, the present invention will be described in more detail with reference to the drawings according to an embodiment of the present invention, but the scope of the present invention is not limited thereto.
[79]
FIG. 1 is a plan view of a pressing jig in a state before being pressurized in a state in which battery cells are embedded according to an embodiment of the present invention, and FIG. 2 is a plan view of a pressing jig in a state in which battery cells are pressed, 3 is a top view of the pressing jig.
[80]
1 to 3, the pressing jig 100,
[81]
It is located at the outermost edge of the plurality of battery cells (111, 112, 113) and between them, separating the space in which the plurality of battery cells (111, 112, 113) are built, and performing pressurization on them. Including a plurality of pressing plates (120: 121, 122, 123, 124), and pressing frames (130: 131, 132) connecting the pressing plates (121, 122, 123, 124) to each other at the top and bottom Pressing unit;
[82]
In order to pressurize the battery cells 1111, 112, 113 with the pressing plates 121, 122, 123, 124, a driving unit 160 for substantially moving the pressing unit is included.
[83]
It will be described in more detail below.
[84]
The pressing frames 130 (131, 132) support and connect the pressing plates 121, 122, 123, 124 while being able to house the battery cells 111, 112, 113.
[85]
At this time, the pressing frame 130 is the pressing plates 121, 122, 123 in the upper and lower portions of the pressing plates 121, 122, 123, 124 in order to solidify the plurality of pressing plates 121, 122, 123, 124. As a structure connecting the, 124, by including the upper pressing frame 131 and the lower pressing frame 132, the pressing plates can receive force from the driving unit as a whole.
[86]
The upper pressing frame 131 is located in the direction in which the electrode terminals 111b of the battery cells 111, 112, 113 protrude, and thus, as in FIG. 3, the electrode terminals 111b are located. It consists of two or more bars so that the part can be opened in an open shape, and the electrode terminals 111b of the battery cells 111, 112, and 113 are exposed between these bars. Although not shown in the drawing, the electrode terminals 111b exposed as described above are connected to each other by a single lead so as to match their polarity at the top. That is, the negative terminals are connected to the negative terminals by one lead, and the positive terminals are connected to the positive terminals by one lead.
[87]
On the other hand, the lower pressurization frame 132 is formed in a plate shape because a space in which the battery cells 111, 112 and 113 can be embedded together with the pressurization plates 121, 122, 123, 124.
[88]
On the other hand, according to the present invention, the pressing jig 100 has a compact structure in a state in which the battery cells are embedded, and between the pair of pressing plates 121 and 124 located at the outermost sides of both sides, the battery cells 111 and 112 On the other hand, the pressing of the 113 must be made, and since the driving unit 160 is included on one side, one pressing plate 121 located at the outermost side of one side is fixed, and the remaining pressing plates 122, 123, 124 are attached to the pressing frames. It allows movement in the pressing direction and horizontal direction while connected (marked with an arrow). Therefore, as shown in Figure 1, after the battery cells (111, 112, 113) are embedded in each position, when mechanical pressure is performed in the direction of the arrow by the driving unit 160, except for the outermost pressure plate 121 on one side. As the pressure plates 122, 123, 124 move in the direction of the outermost pressure plate 121 on one side, the battery cells 111, 112, 113 become a compact pressure jig 100 in a pressed state as shown in FIG. 2. .
[89]
In this way, in order to move and fix the pressing plates 121, 122, 123, 124, the pressing plates 121, 122, 123, 124 are moved and fixed to the pressing frames 130 (131, 132). Devices 131a and 131b such as rails are formed.
[90]
The pressure plates 121, 122, 123, 124 have no bends and have a plate shape corresponding to the shape of the battery cells so that a uniform pressing force can be applied to the entire battery cells 111, 112, 113, and have a certain rigidity. It consists of a material and a predetermined thickness.
[91]
The driving unit 160 has a structure capable of moving the pressing unit described above, and has a structure connected to the pressing plate 124 located at the outermost side of the other side, and has a shape of a pressing rod. The driving unit 160 moves the pressing plates 121, 122, 123, 124.
[92]
Meanwhile, the pressing jig 100 according to the present invention includes a pair of pressing plates 121 and 124 located at the outermost sides of the plurality of pressing plates 121, 122, 123, 124 so that opposite polarities are opposite to each other. It includes magnets 171 and 172. Specifically, all or part of the pair of pressing plates 121 and 124 positioned at the outermost side may be formed of magnets 171 and 172. At this time, the sizes of the magnets 171 and 172 are larger than the size of the battery cells 111 and 113 facing them.
[93]
In this structure, the plurality of battery cells 111, 112, 113 built between the pressure plates 121 and 124 positioned at the outermost side are formed by magnets 171 and 172 facing the opposite polarity. Since the attractive force is applied, in addition to mechanical pressure according to the movement of the driving unit 160, pressurization by magnetic may be simultaneously performed.
[94]
On the other hand, such a pressing jig 100 is inserted into the module case in a state in which a plurality of battery cells 111, 112, 113, 114, 115 are embedded to constitute a battery module.
[95]
4 illustrates a module case 200 in which the pressing jig 100 is embedded according to an exemplary embodiment, and FIG. 5 is a top view of the lower module case 210 in which the pressing jig 100 is embedded. It is shown schematically.
[96]
First, referring to FIG. 4, the module case 200 includes a box-shaped lower module case 210 having an open upper portion and a plurality of battery cells mechanically coupled to the lower module case 210. It includes a plate-shaped upper module case 220 that can completely block the pressed jig from the outside.
[97]
Moreover, the module case 200 further includes a shielding film 230 having a magnetic shielding function so as to shield the magnetism of the magnet included in the pressing jig 100 over the entire inner surface of the module case.
[98]
At this time, the shielding film 230 has a structure in which a conductive material 232 is partially coated on a nonwoven fabric 231 made of a polyester-based material.
[99]
A battery module 300 is manufactured by inserting a pressurizing jig 100 having a plurality of battery cells 111, 112, and 113 built-in and pressed into the module case 200.
[100]
Specifically, the pressing jig 100 is inserted into the lower module case 210 and the upper module case 220 is combined to manufacture a battery module.
[101]
Therefore, since such a battery module continues to pressurize the battery cells 111, 112, and 113 by magnetism as well as mechanical pressure during operation of the battery, the effect of suppressing lithium dendrites can be sustained, so that the battery cells 111 The module case 200 including a shielding film 230 having a shielding function so that other components are not affected by magnets included in the pressing jig 100, as well as improving the life performance of the 112 and 113 Safety can also be secured by using.
[102]
On the other hand, the module case and the battery module shown in FIGS. 3 and 4 are schematically illustrated to show the characteristics according to the present invention, and detailed additional components constituting the module case may include all of the conventionally known ones. .
[103]
6 is a plan view of a pressing jig in a state in which battery cells are embedded according to another embodiment of the present invention.
[104]
Referring to FIG. 6, compared to FIG. 2, the pressing jig 300 includes the pressure plates 321, 324 located at the outermost sides with respect to the horizontal direction of the moving direction of the battery cells 311, 312, 313. There are driving parts 361 and 362 in the form of pressure rods with a structure connected to both sides.
[105]
Since the driving parts 361 and 362 exist on both sides to perform pressing on both sides, all the pressing plates 321, 322, 323, 324 move in the pressing direction and the horizontal direction while being connected to the pressing frames 331, 332 This is possible (marked with an arrow). That is, when mechanical pressure is performed in a direction facing each other by the driving parts 361 and 362, the pressure plates 321, 322, 323, and 324 move left and right, and the battery cells 311, 312, 313) can be pressurized.
[106]
Finally, FIG. 7 shows a plan view of a pressing jig in a state in which battery cells are embedded according to another embodiment of the present invention.
[107]
Referring to FIG. 7, compared to FIG. 2, in the pressing jig 400, all of the pressing plates 421, 422, 423, and 424 are made of magnets, so that the pressing force can be further improved.
[108]
Hereinafter, the contents of the present invention will be described in detail through examples, but the following examples are for illustrating the present invention, and the scope of the present invention is not limited thereto.
[109]

[110]
A positive electrode slurry was prepared by mixing 82% by weight of LiNi 0.6 Co 0.2 Mn 0.2 O 2 as a positive electrode active material, 9% by weight of carbon black as a conductive material, and 9% by weight of PVdF as a binder in NMP as a solvent and mixing them. After coating to a thickness of 50 μm on an aluminum current collector of μm, it was dried at 130° C. to prepare a positive electrode.
[111]
Li metal having a thickness of 50 μm was used as the cathode.
[112]
Between the positive electrode and the negative electrode, both sides of a porous polyethylene substrate, a binder (PVdF) and inorganic particles (Al 2 O 3 ) in the form of interposing an SRS separator formed with an organic-inorganic mixed layer mixed in a 2:8 weight ratio, positive electrode/cathode/ A stack cell of the positive electrode was prepared, and an electrolyte solution in which 1M LiPF 6 was dissolved in a carbonate solvent of EC:EMC=1:2 was injected to prepare a 2.1A pouch-type battery cell.
[113]

[114]
A pressurizing jig in the form as shown in FIG. 1 below was prepared, in which three battery cells prepared in Preparation Example were built, and it was built into the battery module case of FIG. 4.
[115]
Neodymium magnets having a magnetic force of 2000 Gauss were attached to the outermost pressing plates of the pressing jig so that the opposite polarities face each other.
[116]
In addition, mechanical pressure (pressing pressure: 0.80 Mpa) was performed on the pressing jig.
[117]

[118]
In Example 1, the pressure on the battery cell was performed in the same manner as in Example 1, except that a neodymium magnet having a magnetic force of 3500 Gauss was attached to the outermost pressing plates of the pressing jig so that the opposite polarities were opposite to each other. .
[119]

[120]
In Example 1, the pressure on the battery cell was performed in the same manner as in Example 1, except that neodymium magnets having a magnetic force of 5000 Gauss were attached to the outermost pressing plates of the pressing jig so that opposite polarities were opposite to each other. .
[121]

[122]
In Example 1, the pressing of the battery cells was performed in the same manner as in Example 1, except that the pressing plates of the pressing jig were made of neodymium magnets having a magnetic force of 3500 Gauss as shown in FIG. 7 so that opposite polarities were made to face each other. .
[123]

[124]
The battery cell prepared in Preparation Example 1 was prepared, and no separate pressurization was performed.
[125]

[126]
In Example 1, without attaching a magnet to the pressing jig, only mechanical pressing (pressing pressure: 2.00 Mpa) to the battery cell was performed.
[127]

[128]
The battery cells according to Examples 1 to 4 and Comparative Examples 1 to 2 were charged in 0.2C to 4.25V/50mA under a constant current/constant voltage (CC/CV) condition at 25°C in a pressurized state in a pressing jig, and then , Discharge at 0.5C to 3 V under constant current (CC) condition as 1 cycle, measure the thickness of one battery cell in 50 cycles, and the capacity retention rate at that time ((50 th capacity/1 st capacity) x 100 ) Is shown in Table 1 below.
[129]
[Table 1]
[130]
* The total pressing force is the sum of the mechanical pressing force by measuring the pressing force by Gauss with a Gauss meter.
[131]
Referring to Table 1, it can be seen that the higher the Gaussian magnet, the higher the pressing force, and the longer the pressing force, the improved life characteristics.
[132]
In addition, when comparing Comparative Example 2 with Example 1, the total pressing force applied was the same, but it can be seen that the life characteristics of Example 1 in which the pressing by a magnet was performed were more excellent. From this, in the case of adding pressure by a magnet, it can be seen that the overall pressure is uniformly applied differently from the mechanical pressure.
[133]
Those of ordinary skill in the field to which the present invention belongs will be able to perform various applications and modifications within the scope of the present invention based on the above contents.
Industrial availability
[134]
The pressurizing jig according to the present invention includes a magnet to not only mechanically press the battery cells, but also to apply a magnetic force, thereby further improving the pressing force applied to the battery cells and providing a more uniform pressing force, thereby improving battery performance. Can be improved.
[135]
In addition, the battery module according to the present invention includes such a pressing jig, but has a structure capable of shielding magnetism so that the magnetism from the pressing jig does not affect other configurations of the device including the same, Safety can also be secured by solving possible problems.
Claims
[Claim 1]
As a pressurizing jig for performing pressurization of the battery cells, the pressurizing jig separates a space in which a plurality of battery cells are placed at the outermost and between the plurality of battery cells, and the plurality of battery cells A plurality of pressing plates for performing pressing; And pressing frames for connecting the pressing plates to each other at the upper and lower portions of the plurality of pressing plates; A pressing jig that can move in a pressing direction and a horizontal direction while being connected to the pressing frames, and a pair of pressing plates positioned at the outermost sides of both sides of the plurality of pressing plates includes magnets in a form having opposite polarities facing each other. .
[Claim 2]
The method of claim 1, wherein the pressing frames include an upper pressing frame located in a direction in which the electrode terminals of the battery cells protrude, and a lower pressing frame located in a direction opposite to the direction in which the electrode terminals protrude. Including, pressing jig.
[Claim 3]
The pressing jig according to claim 2, wherein the upper pressing frame has two or more bar shapes having a structure parallel to each other.
[Claim 4]
The pressing jig of claim 2, wherein the lower pressing frame has a single plate shape.
[Claim 5]
The pressing jig according to claim 1, wherein a magnet is included in all of the pressing plates in a form having opposite polarities facing each other.
[Claim 6]
The pressing jig according to claim 1 or 5, wherein the magnet is formed on some or all of the pressing plates.
[Claim 7]
The pressing jig according to claim 1 or 5, wherein the magnet is attached to an inner surface or both surfaces of the pressing plates facing the battery cells.
[Claim 8]
The pressing jig according to claim 1 or 5, wherein the area including the magnet is equal to or larger than the area of ​​the battery cell.
[Claim 9]
The pressing jig according to claim 1 or 5, wherein the pressing jig is simultaneously mechanically pressed according to the movement of the pressing unit by the driving unit and pressurized by magnets of different polarities.
[Claim 10]
The pressing jig according to claim 9, wherein the magnetic pressing force is determined by Gauss of magnets included in the pressing plates.
[Claim 11]
The pressing jig according to claim 10, wherein the Gauss is 2000 Gauss or more.
[Claim 12]
The pressure jig according to claim 11, wherein the Gauss is 2000 to 7000 Gauss.
[Claim 13]
A battery module in which a plurality of battery cells are embedded in the pressing jig according to claim 1 or 5 and inserted into the module case in a pressed state.
[Claim 14]
The battery module of claim 13, wherein the plurality of battery cells are lithium metal ion batteries.
[Claim 15]
The method of claim 13, wherein the module case comprises a box-shaped lower module case having an open upper part, and mechanically coupled to the lower module case to completely block a pressure jig in which a plurality of battery cells are embedded from the outside. A battery module comprising a plate or box-shaped upper module case.
[Claim 16]
The battery module according to claim 13, wherein the module case is made of a shielding material so as to shield the magnetism of the pressing jig.
[Claim 17]
The battery module of claim 16, wherein the shielding material is a polyester-based material.
[Claim 18]
The battery module according to claim 13, wherein the module case includes a shielding film having a magnetic shielding function.
[Claim 19]
The battery module according to claim 18, wherein the shielding film is attached to the entire inner or outer surface of the module case.
[Claim 20]
19. The battery module of claim 18, wherein the shielding layer has a structure in which a conductive material is partially or entirely coated on a nonwoven fabric made of a polyester-based material.