Title of Invention: Battery assembly including battery cells capable of simultaneous addition of mechanical pressure and magnetic pressure
Technical field
[One]
This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0014017 filed on February 01, 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 battery assembly including a battery cell capable of simultaneous addition of mechanical pressure and magnetic pressure.
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, by the pressurization, the gap between each component of the electrode assembly inside the battery cell is as compactly contacted as possible, so that the energy density of the battery can be increased, and it is possible to suppress the generation of gas and the growth of lithium dendrites during the subsequent charging and discharging process. , Life performance is also excellent. This is particularly noticeable in lithium metal batteries using lithium metal as a negative electrode active material.
[9]
Meanwhile, the process of pressing the battery cell during the manufacturing process has been performed using a pressing jig, but the pressing during operation of the battery cell has to be limitedly pressed by a battery module case or the like in which the battery cell is embedded. Accordingly, there has been a practical limit to improvement in gas generation and lithium dendrite growth during operation of the battery cell.
[10]
Accordingly, there is a high need for a technology capable of exhibiting more excellent performance by increasing the pressing force by more effectively pressing the battery cells even during operation.
Detailed description of the invention
Technical challenge
[11]
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.
[12]
The present invention provides a battery assembly capable of applying a mechanical pressing force and a magnetic pressing force by a magnet to the battery cells, thereby further improving the pressing force applied to the battery cells and providing a more uniform pressing force, thereby improving battery performance. It aims to improve.
[13]
In addition, the present invention, the battery assembly itself can be a battery module, since it is not necessary to manufacture an additional battery module, it is an object to increase the efficiency in the process.
Means of solving the task
[14]
Therefore, the present invention,
[15]
As a battery assembly capable of pressurizing battery cells,
[16]
The battery assembly,
[17]
A plurality of battery cells;
[18]
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
[19]
Including; a driving unit for moving the pressing unit to pressurize the plurality of battery cells by the pressing plate,
[20]
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,
[21]
Among the plurality of pressure plates, a pair of pressure plates positioned at the outermost sides of each other includes magnets having opposite polarities facing each other, and the other surfaces of the pair of pressure plates except the inner surface facing the battery cells A battery assembly is provided in which a shielding film is formed on a portion exposed to the outside.
[22]
Hereinafter, the present invention will be described in more detail to aid understanding of the present invention.
[23]
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.
[24]
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.
[25]
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.
[26]
The battery cell may have a thin plate shape, and the type thereof is not limited, but in detail, the battery cell may be a pouch-type battery cell requiring steady pressurization due to large external deformation during operation of the battery.
[27]
Meanwhile, according to the present invention, the pressing unit simultaneously serves to pressurize while supporting a plurality of battery cells.
[28]
With such a structure, in the present invention, while mechanical pressure can be performed on a plurality of battery cells, the volume of the entire battery assembly can be minimized.
[29]
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.
[30]
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
[31]
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.
[32]
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.
[33]
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 one side must be fixed in order to transmit the pressing force. Accordingly, in this case, while all the pressing plates are movable, one outermost pressing plate may be arbitrarily fixed, but the outermost pressing plate on one side may be in a non-movable form.
[34]
Accordingly, in the battery assembly according to the present invention, all of the plurality of pressure plates may be in a form in which the rest of the pressure plates except for one pressure plate positioned at the outermost side of one side are movable.
[35]
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.
[36]
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.
[37]
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.
[38]
Accordingly, the pressing frames according to the present invention include an upper pressing frame located in a direction in which the electrode terminals of the battery cells protrude, and a lower pressing frame in parallel with the upper pressing frame and located in a direction opposite to the direction in which the electrode terminals protrude. can do.
[39]
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.
[40]
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.
[41]
The shape of the upper pressing frame and the lower pressing frame is not limited as long as it is a structure connecting the pressing plates, but since the upper pressing frame is located in the direction in which the electrode terminals protrude, electrical connection between the electrode terminals can be smoothly performed thereafter. It is more preferable that the portion where the electrode terminals are located has an open shape.
[42]
Accordingly, the upper pressing frame may be formed in the shape of two or more bars having a structure parallel to each other, and electrode terminals of the battery cells may be exposed between these bars.
[43]
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.
[44]
Meanwhile, as described above, according to the present invention, since the battery assembly has a compact structure and the battery cells must be pressed between a pair of pressure plates positioned at the outermost sides of both sides, the pressure plates are pressed while being connected to the pressure frames. It should be possible to move in both directions and horizontal directions.
[45]
Accordingly, a specific member or device for moving the pressing plates may be formed on the pressing frames, and as an example, a structure such as a rail may be formed, and a structure in which the pressing plates can be moved and fixed. Ramen is not limited.
[46]
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.
[47]
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.
[48]
On the other hand, according to the present invention, the battery assembly includes a magnet in a form having opposite polarities facing each other, and mechanical pressure according to the movement of the pressing part by the driving part with respect to the battery cell, and apart from this, the battery cell also by the magnetism of the magnet. Pressurization of the fields can be made at the same time.
[49]
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.
[50]
In addition, a magnet may be included in all of the pressing plates in a form having opposite polarities facing each other.
[51]
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.
[52]
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.
[53]
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.
[54]
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.
[55]
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.
[56]
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. .
[57]
In this structure, the pressing force due to the magnetism may be determined by Gaussian of the magnets included in the pressing plates.
[58]
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.
[59]
On the other hand, the battery cell included in the battery assembly according to the present invention is not limited, and 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. are possible. However, the volume change due to charging and discharging of the battery cells is large, and the growth of lithium dendrites is mainly a problem. This problem is solved by pressing the battery cells more strongly through the mechanical pressing force by the pressing unit and additional pressing through the magnet. A lithium ion battery, a lithium polymer battery, a lithium ion polymer battery, or a lithium metal ion battery using a lithium metal as a negative electrode active material, or a negative electrode current collector without a negative electrode active material, which can be effectively solved. It may be a lithium free ion battery constituting the negative electrode, and more specifically, a lithium metal ion battery.
[60]
Meanwhile, since the battery assembly of the present invention includes a magnet therein, a shielding film is further included in order to minimize the influence of the magnet on a device to be assembled later.
[61]
Accordingly, the shielding film formed to shield the magnetism of the magnet included in the battery assembly, like the magnet, is formed on the pressure plates located at the outermost sides of both sides.
[62]
However, in the formation position, for the shielding function of the magnet, a shielding film is formed on the other surfaces except for the inner surface facing the battery cells, on the exposed portion to the outside.
[63]
In addition, even when magnets are included in all of the pressing plates with opposite polarities facing each other, a shielding film is formed on the surfaces exposed to the outside on the other surfaces of the pressing plates except for the surfaces facing the battery cells. That is, a shielding film may be formed on the upper portions of the pressing plates in the intermediate position.
[64]
The shape of the shielding film is not limited, but it is preferable to have a light fiber shape so as to minimize an increase in weight of the entire battery assembly.
[65]
Specifically, the shielding film is not limited as long as it is a material having a shielding function, for example, superconducting materials such as Fe, Fe-Si, Cu, and perm Alloy (permalloy), Permendur (Mu), Moly-Permalloy (Moly-Permalloy), MnZn ferrite (ferrite), NiZn ferrite, CuZn ferrite, Garnet (garnet) The material may be mixed or may have a structure in which Cu, which is a superconducting material, is partially or entirely coated on a polymer fiber made of a polyester-based material by electroless plating.
[66]
By including the shielding film as described above, the battery assembly according to the present invention can be continuously applied mechanically and magnetically during the operation of the battery cells. While minimizing the problems such as, it is possible to minimize problems that may affect other components by the shielding film.
[67]
The battery assembly itself may be a battery module, and in this case, the pressing unit and the driving unit may be a module case itself in which a plurality of battery cells are embedded.
[68]
Meanwhile, other components required for the battery module, for example, detailed structures such as an external terminal, may include all conventionally known components.
Brief description of the drawing
[69]
1 is a plan view of a battery assembly showing a state before the battery cells are pressed according to an embodiment of the present invention;
[70]
2 is a plan view of the battery assembly showing a state in which the battery cells of the battery assembly of FIG. 1 are pressed;
[71]
3 is a top view of the battery assembly of FIG. 2;
[72]
4 is a plan view of a battery assembly according to another embodiment of the present invention;
[73]
5 is a plan view of a battery assembly according to another embodiment of the present invention;
[74]
6 is a plan view of a battery assembly showing a state in which battery cells are pressed according to an embodiment of the present invention;
[75]
7 is a top view of the battery assembly of FIG. 6;
Mode for carrying out the invention
[76]
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.
[77]
FIG. 1 is a plan view of a battery assembly in a state before the battery cells are pressed according to an embodiment of the present invention, and FIG. 2 is a plan view of the battery assembly in a state in which the battery cells are pressed, and FIG. A top view of the battery assembly is shown.
[78]
1 to 3, the battery assembly 100,
[79]
A plurality of battery cells 111, 112, 113;
[80]
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;
[81]
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.
[82]
It will be described in more detail below.
[83]
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.
[84]
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.
[85]
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.
[86]
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.
[87]
Meanwhile, according to the present invention, while the battery assembly 100 has a compact structure, the battery cells 111, 112, 113 must be pressed between a pair of pressing plates 121 and 124 located at the outermost sides of both sides. Meanwhile, 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 connected to the pressing frames in the pressing direction and the horizontal direction. Make it possible to move (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 battery assembly 100 in a pressed state as shown in FIG. 2. .
[88]
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.
[89]
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.
[90]
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.
[91]
Meanwhile, the battery assembly 100 according to the present invention includes a pair of pressure plates 121 and 124 positioned at the outermost sides of the plurality of pressure plates 121, 122, 123, 124 so that opposite polarities face 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.
[92]
In such a structure, the plurality of battery cells (111, 112, 113) built between the pressure plates (121, 124) located at the outermost are applied by the magnets (171, 172), so the driving unit In addition to the mechanical pressure caused by the movement of the 160, magnetic pressure may be simultaneously performed.
[93]
In addition, the battery assembly 100, the magnets 171, 172 on the outermost pressing plates 121, 124 based on the pressing direction and the horizontal direction of the battery cells 111, 112, 113 Shielding films 181 and 182 having a magnetic shielding function are further included in order to shield the magnetism of the device.
[94]
At this time, the shielding layers 181 and 182 are formed on the remaining surfaces except for the inner surface facing the battery cells 111 and 113, respectively. Accordingly, when viewed from the top as shown in FIG. 3, the outermost pressing plates 121 and 124 are covered by the shielding films 181 and 182.
[95]
The shielding layers 181 and 182 have a structure in which a polymer fiber made of a polyester-based material is partially or entirely coated with a superconducting material.
[96]
Therefore, since the battery assembly 100 continues to pressurize the battery cells 111, 112, and 113 by magnetism along with mechanical pressure even during operation of the battery, the effect of suppressing lithium dendrites can be maintained. In addition to improving the lifetime performance of the fields 111, 112, 113, the bar includes shielding films 181 and 182 having a shielding function so that other components are not affected by the magnets 171 and 172. Also, safety can be secured.
[97]
Meanwhile, in FIGS. 4 and 5, plan views of battery assemblies 200 and 300 according to still another exemplary embodiment of the present invention are shown.
[98]
First, referring to Figure 4, compared to Figure 2, the difference in that the magnets (271, 272) are attached to the inner surface facing the battery cells (211, 213) at the outermost pressure plates (221, 224) Have.
[99]
Referring to FIG. 5, compared to FIG. 2, the battery assembly 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.
[100]
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 units 361 and 362, the pressing plates 321, 322, 323, and 324 move left and right, and the battery cells 311, 312, 313 becomes a compact battery assembly 300 in a pressurized state.
[101]
6 and 7 are plan views of battery assemblies 200 and 300 according to still another embodiment of the present invention.
[102]
Referring to FIG. 6, compared to FIG. 2, in the battery assembly 400, all the pressing plates 421, 422, 423, 424 are made of magnets, so that the pressing force can be further improved, and the shielding films 481, 482, 483, 484 are formed on the remaining surfaces except for the surface facing the battery cells 411, 412, 413, respectively. Accordingly, referring to FIG. 7, the pressing plates 421, 422, 423, and 424 are covered by the shielding films 481, 482, 483, and 484.
[103]
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.
[104]
On the other hand, since the following examples are only to confirm the effect of the pressurization by the magnet, it was performed on one battery cell.
[105]

[106]
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.
[107]
Li metal having a thickness of 50 μm was used as the cathode.
[108]
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.
[109]

[110]
A battery assembly was prepared in the form as shown in FIG. 4 so that three battery cells prepared in Preparation Example can be embedded to perform pressurization. Neodymium magnets having a magnetic force of 2000 gauss (area and thickness control) were attached to the pressure plates on both sides of the battery cell so that opposite polarities face each other.
[111]
Prepare a non-woven polyester fiber fabric (TORAY, TETORON), and immerse the polyester fiber in a copper sulfate (CuSO 4 ) immersion solution containing Cu as a superconductor, and add formaldehyde as a reducing agent to the non-woven fabric. Cu was coated with electroless plating to prepare a shielding film.
[112]
The shielding film was attached to the pressing plates as shown in FIG. 4.
[113]
In addition, mechanical pressure (pressing pressure: 0.80 Mpa) was performed.
[114]

[115]
In Example 1, pressurization was performed on the battery cell in the same manner as in Example 1, except that neodymium magnets having a magnetic force of 3500 Gauss were attached so that opposite polarities were opposite to each other.
[116]

[117]
In Example 1, pressurization was performed on the battery cell in the same manner as in Example 1, except that neodymium magnets having a magnetic force of 5000 Gauss were attached so that opposite polarities were opposite to each other.
[118]

[119]
In Example 1, the pressing of the battery cell was performed in the same manner as in Example 1, except that the platens of the battery assembly were made of neodymium magnets having a magnetic force of 3500 Gauss as shown in FIG. .
[120]

[121]
The battery cell prepared in Preparation Example 1 was prepared to prepare a battery assembly in the form as shown in FIG. 4 (there is one built-in battery cell), and neither a magnet was attached nor a separate mechanical pressure was performed.
[122]

[123]
In Example 1, without attaching a magnet, only mechanical pressure (pressing pressure: 2.00 Mpa) to the battery cell was performed.
[124]

[125]
The battery cells of the battery assemblies according to Examples 1 to 4 and Comparative Examples 1 to 2 were charged at 0.2C to 4.25V/50mA under a constant current/constant voltage (CC/CV) condition at 25 °C, and then constant current (CC). As a condition, discharge at 0.5C to 3 V as 1 cycle, and 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. Shown in.
[126]
[Table 1]
[127]
* The total pressing force is the sum of the mechanical pressing force by measuring the pressing force by Gauss with a Gauss meter.
[128]
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.
[129]
In addition, when comparing Comparative Example 2 with Example 1, it can be seen that the total pressing force applied was the same, but the increase in the cell thickness of Example 1 in which the pressing by a magnet was performed was small and the life characteristics 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.
[130]
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
[131]
The battery assembly according to the present invention, by including a magnet, can be applied not only to mechanical pressure to the battery cells, but also to apply magnetic pressure, further improving the pressing force applied to the battery cells, and providing a more uniform pressing force. By providing, the battery performance can be improved.
[132]
In addition, the battery assembly according to the present invention includes a shielding film capable of shielding magnetism so as not to affect other configurations of devices including the same, and thus safety can also be secured by solving problems that may be caused by magnetism. .
Claims
[Claim 1]
A battery assembly capable of pressurizing a battery cell, wherein the battery assembly comprises: a plurality of battery cells; 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 top and bottom of the pressing plates, and a driving unit for moving the pressing unit to press the plurality of battery cells with the pressing plates, and the All of the plurality of pressure plates, or the rest of the pressure plates excluding only one pressure plate located at the outermost side of one side, can be moved in the pressure direction and horizontal direction while being connected to the pressure frames, and are located at the outermost sides of both sides of the plurality of pressure plates. A pair of pressurizing plates that have opposite polarities to each other includes a magnet, and the remaining surfaces of the pair of pressurizing plates except the inner surface facing the battery cells are formed with a shielding film on the exposed area. There, the battery assembly.
[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. Containing, battery assembly.
[Claim 3]
The battery assembly 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 battery assembly of claim 2, wherein the lower pressing frame has a single plate shape.
[Claim 5]
The method of claim 1, wherein a magnet is included in all the pressing plates in a form having opposite polarities facing each other, and a shielding film is formed on the surfaces exposed to the outside on the other surfaces of the pressing plates except for the surfaces facing the battery cells. The battery assembly.
[Claim 6]
The battery assembly according to claim 1 or 5, wherein the magnet is formed on some or all of the pressure plates.
[Claim 7]
The battery assembly according to claim 1 or 5, wherein the magnet is attached to the inner surface or both surfaces of the pressure plates facing the battery cells.
[Claim 8]
The battery assembly 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 battery assembly according to claim 1 or 5, wherein the battery assembly is simultaneously mechanically pressurized according to movement of the pressurizing unit by the driving unit and pressurized by magnets of different polarities with respect to the plurality of battery cells.
[Claim 10]
The battery assembly according to claim 9, wherein the magnetic pressing force is determined by Gaussian of magnets included in the pressing plates.
[Claim 11]
The battery assembly according to claim 10, wherein the Gauss is 2000 Gauss or more.
[Claim 12]
The battery assembly according to claim 11, wherein the Gauss is 2000 to 7000 Gauss.
[Claim 13]
The battery assembly of claim 1, wherein the plurality of battery cells are lithium metal ion batteries.
[Claim 14]
The battery assembly according to claim 1 or 5, wherein the shielding film has a structure in which a polymer fiber made of a polyester-based material is partially or entirely coated with a superconducting material.
[Claim 15]
The battery assembly of claim 1, wherein the battery assembly is a battery module.