KR102261691B1 - Irregular Battery Cell with Transformable Structure - Google Patents

Abstract

The present invention includes two or more electrode assemblies each including a positive electrode, a negative electrode, and a separator, a non-aqueous electrolyte, and a battery case accommodating the electrode assemblies together with the electrolyte; Two or more unit cells having a structure in which electrode assemblies are independently accommodated and sealed together with an electrolyte in the battery case, and the battery case are positioned between the unit cells in an extended state and pivotally rotated and/or bent It provides a battery cell, characterized in that it is composed of a variable-type part of the structure.

Description

Irregular Battery Cell with Transformable Structure

The present invention relates to an amorphous battery cell having a structure that can be deformed.

With the increase in technology development and demand for mobile devices, the demand for secondary batteries is also rapidly increasing. Among them, lithium secondary battery cells with high energy density and operating voltage and excellent preservation and lifespan characteristics are used in various electronic products as well as various mobile devices. It is widely used as an energy source for

Lithium secondary battery cells are largely classified into cylindrical battery cells, prismatic battery cells, pouch-type battery cells, etc. according to their appearance, and can be classified into lithium ion battery cells, lithium ion polymer battery cells, lithium polymer battery cells, etc. according to the type of electrolyte. also classified.

Due to the recent trend toward miniaturization of mobile devices, the demand for thin prismatic batteries and pouch-type battery cells is increasing.

In general, a pouch-type battery cell refers to a battery in which an electrode assembly and an electrolyte are sealed inside a pouch-type case of a laminate sheet including a resin layer and a metal layer. The electrode assembly accommodated in the battery case has a structure of a jelly-roll type (winding type), a stack type (stacking type), or a complex type (stacking/folding type).

1 schematically shows the structure of a battery cell including a jelly roll-type electrode assembly.

Referring to FIG. 1 , the battery cell 11 includes an electrode assembly 2 , electrode leads 4 and 5 protruding from one end of the electrode assembly 2 , and a battery case accommodating the electrode assembly 3 . (3) is included. In such a battery cell 1, the battery case 3 is sealed in a state in which the electrode assembly 2 is embedded in the battery case 3 together with the electrolyte, and thus has a plate-shaped structure as a whole.

However, recently, a high-capacity secondary battery system is required in order to secure the maximum available time by using a battery cell and a trend change of a slim type or various designs.

Accordingly, by combining and arranging a plurality of battery cells, a battery pack having a high capacity and a specific shape may be configured.

However, while a battery pack requires a plurality of battery cells, since a series of manufacturing processes of accommodating the electrode assembly in the battery case and injecting the electrolyte solution must be applied to each of the plurality of battery cells, a battery using a plurality of battery cells It takes a long time to manufacture the pack, and the manufacturing cost is also very high.

Moreover, since the battery pack has a structure in which a plurality of battery cells are arranged and stacked, it is not easy to be disposed in a narrow space or a space in which curves and curves are formed because of the large volume due to the battery case and separate fastening members of the battery cells , the electrical connection between the battery cells is very complicated.

Therefore, there is a high need for a battery cell that has a simple manufacturing process and a high capacity, and can be installed in devices of various designs.

An object of the present invention is to solve the problems of the prior art as described above and the technical problems that have been requested from the past.

Specifically, an object of the present invention is to embed two or more electrode assemblies together with an electrolyte in a battery case to realize high capacity and to greatly reduce manufacturing time and cost, and to change the shape to correspond to the shape of various devices. It is to provide a battery cell capable of

The battery cell according to the present invention for achieving this object includes two or more electrode assemblies each including a positive electrode and a negative electrode and a separator, a non-aqueous electrolyte, and a battery case accommodating the electrode assemblies together with the electrolyte therein. there is;

Two or more unit cells having a structure in which electrode assemblies are independently accommodated and sealed together with an electrolyte in the battery case, and the battery case are positioned between the unit cells in an extended state and pivotally rotated and/or bent It is characterized in that it is composed of a variable-type part of the structure.

That is, since the battery cell according to the present invention has a structure in which two or more electrode assemblies are each independently accommodated in one battery case, high capacity is possible, and the manufacturing cost and manufacturing time of the battery cell compared to the capacity can be greatly reduced. can

In addition, since the battery cell can be deformed in shape to correspond to the internal structure of the device through the deformable part, it is possible to maximize the use of the internal space of the device.

Accordingly, the battery case may be a pouch-type battery case that is easily deformable, and more specifically, may be formed of a laminate sheet including a resin layer and a metal layer.

The battery case is composed of a case body having two or more mounting parts in which each of the electrode assemblies are accommodated, and a cover extending from one end of the case body or made of an independent member with respect to the case body, and the battery The case may have a structure in which the case body and at least a portion of the cover are heat-sealed and coupled to each other while the cover is in close contact with the case body.

The specific structure of the mounting part may be a structure that is depressed downward or upward from the case body in a shape corresponding to the electrode assembly. That is, the mounting part has a structure that covers the remaining surfaces except for the upper surface of the electrode assembly in a state in which the electrode assembly is mounted, and the cover may be heat-sealed and sealed to the case body in the state in which the electrode assembly is mounted.

The case body may include a first fusion part extending between the mounting parts; and second fusion parts extending outwardly from the ends of each of the mounting parts except for the first fusion part.

The cover is configured to cover the upper front surface of the case body, and a recessed mounting part and a first fusion part and a second fusion part which are the remaining areas that are not recessed are formed on the upper front surface of the case body, and the cover is the upper front surface of the case body When positioned in the, the first fusion portion and the second fusion portion except for the mounting portion are in close contact with the cover, and accordingly, their contact surfaces may be heat-sealed and sealed, respectively.

In this case, when the first fusion part is thermally fused while the case body and the cover are in close contact, the deformable part of the battery cell is formed.

As such, the heat-sealed deformable part is formed between unit cells sealed by a cover with an electrode assembly embedded in each mounting part, and the unit cells are rotated or bent around the deformable part to change the overall shape of the battery cell. can be deformed.

After the first fusion part is heat-sealed with the cover to form a deformable part, the first fusion part may be configured to have a relatively thin thickness so that the deformable part is easily deformed, and in detail, to have a thickness of 50% to 90% compared to the thickness of the second fusion part. can

When the thickness of the first fusion part is less than 50% of the thickness of the second fusion part, the first fusion part may be broken from the second fusion part in the thermal fusion process, and defects such as swells or wrinkles may occur, and , the mechanical rigidity of the variable type part, on which the heat bonding of the first fusion part and the cover has been completed, is also very weak, so that the battery case may be damaged by cracks originating from the swells or wrinkles formed in the deformable part during movement such as rotation or bending. Therefore, it is not advisable

On the other hand, when the thickness of the first fusion part exceeds 90% of the thickness of the second fusion part, the first fusion part and the cover are excessively hardened by heat, and rotation or bending of the deformable part is not easy. don't

The width of the first fusion part may be configured flexibly in response to a desired size and shape change of the battery cell, but it is not only possible to rotate or bend the deformable part, but is also selected within a range that does not significantly increase the overall volume of the battery cell. Preferably, it may be 10% to 100% of the width of one mounting part in detail.

The deformable part also includes two or more reinforcement members formed on one surface of the first fusion part facing the cover and extending from an end of the first fusion part adjacent to the mounting part to the other end adjacent to another mounting part. can

The reinforcing member is a member that provides resistance to the deformable part when the deformable part is deformed and maintains the shape of the deformable part after deformation. It is possible to prevent the deformable or deformable part from being restored again.

In one specific example, the reinforcing member may be a plate-shaped plate or a metal plate having a honeycomb structure, and an electrically insulating film may be attached to a surface thereof.

In another example, the reinforcing member is a metal plate, and an electrically insulating film is attached to a surface thereof,

In order to have rigidity in oblique bending, it may have a structure extending from the end of the first fusion part in an 'X' shape on a plane to the other end direction adjacent to another mounting part.

This structure provides an advantage of easily maintaining the bent shape of the deformable part while maintaining a portion thereof when the reinforcing member is bent obliquely.

Alternatively, the reinforcing member may be a metal plate, an electrically insulating film is attached to its surface, and may have a structure in which a concave-convex structure recessed across a central portion is formed to facilitate vertical bending.

Accordingly, the reinforcing member may be relatively easily deformed through the concave-convex portion having a relatively thin thickness, and the stress applied to the deformable portion may be relieved by that amount.

The thickness of the reinforcing member may be 100% to 1000% of the thickness of the first fusion part.

When the thickness of the reinforcing member is less than 100% of the thickness of the first fusion part, sufficient rigidity and resistance to deformation cannot be provided to the deformable part, so it is difficult to expect a desired effect, and 1000% compared to the thickness of the first fusion part %, not only is it not easy to heat-seal the third sealing scheduled part, but also may cause defects such as a step difference on the outer surface of the battery cell, which is not preferable.

The material of the metal plate constituting the reinforcing member is not particularly limited, but may be one or more selected from lead, copper, and aluminum having excellent ductility.

The second fusion parts may be heat-sealed while the case body is in close contact with the cover to form outer periphery sealing parts of the battery cell.

Here, in each of the electrode assemblies, electrode leads may protrude to the outside of the battery case through at least one of the outer circumferential sealing parts.

In one specific example, in the electrode assemblies, their electrode leads may protrude through different outer circumferential sealing parts.

Accordingly, in the battery cell having the above structure, the electrode leads of each of the electrode assemblies can protrude in different directions, and the electrical connection structure of each of the electrode assemblies can be independently configured.

For example, one electrode assembly may be electrically connected to an electric device at one side of the battery cell, and another electrode assembly may be electrically connected to another electric device at the other side of the battery cell.

Each of these electrode assemblies may include a pair of electrode leads, that is, a positive electrode lead and a negative electrode lead, and these electrode leads may have a structure in which they protrude side by side from one end of the electrode assembly.

Alternatively, the electrode assemblies may have a structure in which their electrode leads each protrude through the same outer circumferential sealing part.

The battery cell having the above structure has an advantage in that it is easy to electrically connect the electrode assemblies to each other since the electrode leads of each of the electrode assemblies protrude in the same direction.

At this time, each of the electrode assemblies includes a pair of electrode leads, that is, a positive electrode lead and a negative electrode lead, and the structure or electrode leads in which these electrode leads protrude side by side from one end of the electrode assembly are formed at both ends of the electrode assembly. Each may have a protruding structure.

In another specific example, a portion where the electrode lead of one electrode assembly and the electrode lead of another electrode assembly adjacent to the electrode assembly are electrically connected may be located between the cover inside the deformable part and the first fusion part.

In this structure, since the electrode leads of the electrode assembly are connected between the first fusion part and the cover, when the deformable part is rotated or bent, the combined electrode leads can also be rotated or bent together, and the electrical connection structure between the electrode assemblies is Since it is not formed outside the battery cell, the battery cell may have a more compact structure.

Among the outer peripheral sealing parts, the remaining outer peripheral sealing parts to which the electrode leads do not protrude may be bent in the direction of the mounting part.

On the other hand, in one specific example, the battery cell,

n (n≥2) electrode assemblies include n unit cells connected to each other by deformable parts,

Based on the first unit cell, each of the second to nth unit cells is rotated by 0 degrees to 180 degrees by the deformable parts, and/or in the nth unit cell direction with respect to the first unit cell. A bent structure can be achieved.

That is, the battery cell according to the present invention has a structure in which a plurality of electrode assemblies are accommodated in one battery case, and may include a plurality of unit cells that can be used as an independent power source in a single battery cell, and thus a large-capacity battery Cell manufacturing can be greatly simplified.

In addition, the battery cell can diversify the overall shape of the battery cell by deforming the deformable part formed between the unit cells, and accordingly, the battery cell can be arranged to correspond to spaces of various structures.

For example, when a vertical structure is formed in a space for battery cells to be disposed, the deformable part between the unit cells is vertically bent, so that one unit cell and another unit cell are perpendicular to each other and disposed in the space. it can be

In addition, in the battery cell of the present invention, since the n-th unit cells can independently supply power to different electrical devices, power can be supplied to a plurality of electrical devices through one battery cell, and such electrical connection Through this, it has the advantage of being able to diversify the utilization of the battery cell.

For example, in a battery cell, one unit cell is used as a main power source of an electric device, and another unit cell is used as an auxiliary power source when the main power is cut off to extend the available time of the electric device, or A unit cell supplies power to a system built in an electric device, and another unit cell may be utilized in a form of supplying power to the electric device itself.

In the n-th unit cells, adjacent unit cells from the first unit cell to the n-th unit cell may be connected in series and/or in parallel to each other.

In such a battery cell, the electrode assembly is a jelly-roll type electrode assembly having a structure in which a separation sheet is interposed between a positive electrode sheet and a negative electrode sheet, and the unit cell is a plate-shaped ) structure, and the anode lead and the cathode lead of the electrode assembly may have a structure protruding side by side from one end of the electrode assembly, or a structure protruding from both ends of the electrode assembly, respectively.

The present invention also provides a method for manufacturing the battery cell.

The method is specifically,

(a) the process of mounting each of the electrode assemblies to the mounting parts of the battery case;

(b) injecting an electrolyte into each mounting part;

(c) forming an outer periphery sealing part by attaching the case body and the cover of the battery case and heat-sealing the second fusion parts; and

(d) forming a deformable part by heat-sealing the first fusion part;

includes

The process of injecting the electrolyte may be performed simultaneously, and in some cases, a method of injecting the electrolyte through one mounting part and injecting the electrolyte into another mounting part through the first fusion part may be used.

The method according to the present invention consists of a simple process of mounting a plurality of electrode assemblies in one battery case and then sealing them, so that the manufacturing time and cost of the battery cell can be significantly reduced.

In the present invention, the type of the battery cell is not particularly limited, but as a specific example, a lithium ion (Li-ion) secondary battery, lithium polymer (Li-polymer) having advantages such as high energy density, discharge voltage, output stability, etc. ) may be a secondary battery, or a lithium secondary battery such as a lithium ion polymer (Li-ion polymer) secondary battery.

In general, a lithium secondary battery is composed of a positive electrode, a negative electrode, a separator, and a lithium salt-containing non-aqueous electrolyte.

The positive electrode, for example, is prepared by coating a mixture of a positive electrode active material, a conductive material, and a binder on a positive electrode current collector and/or an extended current collector and then drying, and, if necessary, further adding a filler to the mixture do.

The positive electrode current collector and/or the extended current collector is generally made to have a thickness of 3 to 500 micrometers. The positive electrode current collector and the extended current collector are not particularly limited as long as they have high conductivity without causing a chemical change in the battery, and for example, stainless steel, aluminum, nickel, titanium, sintered carbon, or aluminum. A stainless steel surface treated with carbon, nickel, titanium, silver, or the like may be used. The positive electrode current collector and the extended current collector may form fine irregularities on the surface thereof to increase the adhesive force of the positive electrode active material, and various forms such as films, sheets, foils, nets, porous bodies, foams, and nonwovens are possible.

The positive active material may _{include a layered compound such as lithium cobalt oxide (LiCoO 2} ), lithium nickel oxide (LiNiO ₂ ), or a compound substituted with one or more transition metals; Lithium manganese oxides such as Formula Li _1+x Mn _2-x O ₄ (where x is 0 to 0.33), LiMnO ₃ , LiMn ₂ O ₃ , and LiMnO _{2 ;} lithium copper oxide (Li ₂ CuO ₂ ); vanadium oxides such as LiV ₃ O ₈ , LiFe ₃ O ₄ , V ₂ O ₅ , and Cu ₂ V ₂ O _{7 ;} Ni site-type lithium nickel oxide represented by the formula LiNi _1-x M _x O ₂ (wherein M = Co, Mn, Al, Cu, Fe, Mg, B or Ga, and x = 0.01 to 0.3); Formula LiMn _2-x M _x O ₂ (where M = Co, Ni, Fe, Cr, Zn or Ta and x = 0.01 to 0.1) or Li ₂ Mn ₃ MO ₈ (where M = Fe, Co, lithium manganese composite oxide represented by Ni, Cu or Zn; _{LiMn 2} O _{4 in} which a part of Li in the formula is substituted with an alkaline earth metal ion; disulfide compounds; And the like Fe ₂ (MoO _{4) 3,} but is not limited to these.

The conductive material is typically added in an amount of 1 to 30% by weight based on the total weight of the mixture including the positive active material. Such a conductive material is not particularly limited as long as it has conductivity without causing a chemical change in the battery. For example, graphite such as natural graphite or artificial graphite; carbon black, such as carbon black, acetylene black, Ketjen black, channel black, furnace black, lamp black, and summer black; conductive fibers such as carbon fibers and metal fibers; metal powders such as carbon fluoride, aluminum, and nickel powder; conductive whiskeys such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; A conductive material such as a polyphenylene derivative may be used.

The binder is a component that assists in bonding between the active material and the conductive material and bonding to the current collector, and is typically added in an amount of 1 to 30% by weight based on the total weight of the mixture including the positive active material. Examples of such binders include polyvinylidene fluoride, polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene , polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butyrene rubber, fluororubber, various copolymers, and the like.

The filler is optionally used as a component for inhibiting the expansion of the positive electrode, and is not particularly limited as long as it is a fibrous material without causing a chemical change in the battery. For example, an olipine-based polymer such as polyethylene or polypropylene; A fibrous material such as glass fiber or carbon fiber is used.

The negative electrode is manufactured by coating and drying the negative electrode active material on the negative electrode current collector and/or the extended current collector, and if necessary, the above-described components may be optionally further included.

The negative current collector and/or the extended current collector is generally made to have a thickness of 3 to 500 micrometers. Such a negative current collector and/or extended current collector is not particularly limited as long as it has conductivity without causing chemical change in the battery, and for example, copper, stainless steel, aluminum, nickel, titanium, fired carbon, Copper or stainless steel surface-treated with carbon, nickel, titanium, silver, etc., aluminum-cadmium alloy, etc. may be used. In addition, like the positive electrode current collector, the bonding force of the negative electrode active material may be strengthened by forming fine irregularities on the surface, and may be used in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a non-woven body.

Examples of the negative electrode active material include carbon such as non-graphitizable carbon and graphitic carbon; Li _x Fe ₂ O ₃ (0≤x≤1), Li _x WO ₂ (0≤x≤1), Sn _x Me _1-x Me' _y O _z (Me: Mn, Fe, Pb, Ge; Me' : metal composite oxides such as Al, B, P, Si, elements of Groups 1, 2, and 3 of the periodic table, halogen; 0 < x ≤ 1; 1 ≤ y ≤ 3; 1 ≤ z ≤ 8); lithium metal; lithium alloy; silicon-based alloys; tin-based alloys; SnO, SnO ₂ , PbO, PbO ₂ , Pb ₂ O ₃ , Pb ₃ O ₄ , Sb ₂ O ₃ , Sb ₂ O ₄ , Sb ₂ O ₅ , GeO, GeO ₂ , Bi ₂ O ₃ , Bi ₂ O ₄ , and metal oxides such as _{Bi 2} O _{5 ;} conductive polymers such as polyacetylene; A Li-Co-Ni-based material or the like can be used.

The separator is interposed between the anode and the cathode, and an insulating thin film having high ion permeability and mechanical strength is used. The pore diameter of the separator is generally 0.01 to 10 micrometers, and the thickness is generally 5 to 300 micrometers. As such a separation membrane, For example, olefin polymers, such as chemical-resistant and hydrophobic polypropylene; A sheet or nonwoven fabric made of glass fiber or polyethylene is used. When a solid electrolyte such as a polymer is used as the electrolyte, the solid electrolyte may also serve as a separator.

The electrolyte may be a lithium salt-containing non-aqueous electrolyte, and includes a non-aqueous electrolyte and a lithium salt. As the non-aqueous electrolyte, a non-aqueous organic solvent, an organic solid electrolyte, an inorganic solid electrolyte, etc. are used, but are not limited thereto.

Examples of the non-aqueous organic solvent include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma -Butyl lactone, 1,2-dimethoxy ethane, tetrahydroxy franc, 2-methyl tetrahydrofuran, dimethyl sulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane , acetonitrile, nitromethane, methyl formate, methyl acetate, phosphoric acid triester, trimethoxymethane, dioxolane derivative, sulfolane, methyl sulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbo An aprotic organic solvent such as a nate derivative, a tetrahydrofuran derivative, ether, methyl pyropionate, or ethyl propionate may be used.

Examples of the organic solid electrolyte include polyethylene derivatives, polyethylene oxide derivatives, polypropylene oxide derivatives, phosphoric acid ester polymers, poly agitation lysine, polyester sulfide, polyvinyl alcohol, polyvinylidene fluoride, A polymer containing an ionic dissociation group or the like can be used.

Examples of the inorganic solid electrolyte include Li ₃ N, LiI, Li ₅ NI ₂ , Li ₃ N-LiI-LiOH, LiSiO ₄ , LiSiO ₄ -LiI-LiOH, Li ₂ SiS ₃ , Li ₄ SiO ₄ , Nitrides, halides, sulfates, etc. of Li such as Li ₄ SiO ₄ -LiI-LiOH, Li ₃ PO ₄ -Li ₂ S-SiS _{2 and the like may be used.}

The lithium salt is a material easily soluble in the non-aqueous electrolyte, for example, LiCl, LiBr, LiI, LiClO ₄ , LiBF ₄ , LiB ₁₀ Cl ₁₀ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , LiAsF _{6, LiSbF 6, LiAlCl 4,} CH 3 SO 3 Li, CF 3 SO 3 Li, (CF 3 SO 2) 2 NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenyl borate and imide have.

In addition, for the purpose of improving charge/discharge characteristics, flame retardancy, etc. in the nonaqueous electrolyte, for example, pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, n-glyme, hexaphosphate triamide, Nitrobenzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N,N-substituted imidazolidines, ethylene glycol dialkyl ethers, ammonium salts, pyrrole, 2-methoxyethanol, aluminum trichloride, etc. may be added. have. In some cases, in order to impart incombustibility, a halogen-containing solvent such as carbon tetrachloride and ethylene trifluoride may be further included, and carbon dioxide gas may be further included to improve high temperature storage characteristics, and FEC (Fluoro-Ethylene) Carbonate), PRS (Propene Sultone), etc. may be further included.

In one specific example, LiPF ₆ , LiClO ₄ , LiBF ₄ , LiN(SO ₂ CF ₃ ) ₂ Lithium salt such as a cyclic carbonate of EC or PC and a low-viscosity solvent of DEC, DMC or EMC A lithium salt-containing non-aqueous electrolyte may be prepared by adding it to a mixed solvent of linear carbonate.

The present invention also provides a battery pack including one or more battery cells and one or more devices using the battery pack as a power source.

The device may be, for example, a mobile electronic device, a wearable electronic device, an unmanned aerial vehicle, or an electric bicycle, but is not limited thereto.

As described above, the battery cell according to the present invention has a structure in which two or more electrode assemblies are each independently accommodated in a single battery case, and thus not only high capacity, but also manufacturing cost and manufacturing time can be greatly reduced. have.

In addition, since the shape of the battery cell can be changed in response to the internal structure of the device through the deformable part, it can be used in response to the design of various devices.

1 is an exploded perspective view of a battery cell according to the prior art;
2 is an exploded perspective view of a battery cell according to an embodiment of the present invention;
Fig. 3 is a schematic plan view of the case body;
4 is a schematic plan view of a battery cell;
5 is a schematic diagram showing a shape deformation process of a battery cell;
6 is a schematic diagram showing the structures of a battery cell with a deformed shape;
7 is a schematic diagram showing other structures of a battery cell with a deformed shape;
8 is a schematic diagram showing other structures of a battery cell with a deformed shape;
9 is a schematic plan view of a battery cell according to another embodiment of the present invention;
10 is a schematic plan view of a battery cell according to another embodiment of the present invention;
11 is a schematic plan view of a battery cell according to another embodiment of the present invention;
12 is a schematic plan view of a case body constituting a battery cell according to another embodiment of the present invention;
13 is a schematic plan view of a case body constituting a battery cell according to another embodiment of the present invention.

Hereinafter, although described with reference to the drawings according to the embodiment of the present invention, this is for easier understanding of the present invention, and the scope of the present invention is not limited thereto.

2 is an exploded perspective view of a battery cell according to an embodiment of the present invention is schematically shown, FIG. 3 is a schematic plan view of the case body, and FIG. 3 is a schematic plan view in which the case body and the cover are combined. is shown.

Referring to these drawings together, the battery cell 100 includes a first electrode assembly 120 , a second electrode assembly 122 , an electrolyte (not shown), and a battery case 110 .

Each of the first electrode assembly 120 and the second electrode assembly 122 is a jelly-roll type electrode assembly having a structure in which a separation sheet is interposed between the positive electrode sheet and the negative electrode sheet.

The first electrode assembly 120 includes a positive electrode lead 120a and a negative electrode lead 120b, and the second electrode assembly 122 includes a positive electrode lead 122a and a negative electrode lead 122b, and these electrode leads Reference numerals 120a, 120b, 122a, and 122b protrude side by side from one end of the first electrode assembly 120 and the second electrode assembly 122 .

The battery case 110 extends from one end of the case body 112 and the case body 112 in which the first electrode assembly 120 and the second electrode assembly 122 are accommodated, and the upper part of the case body 112 . A cover 114 having a size corresponding to the area is included. Here, although the structure in which the cover 114 extends from one end of the case body 112 is shown in FIG. 2 , the cover 114 made of an independent member with respect to the case body 112 is also within the scope of the present invention. included, of course.

The case body 112 is formed with a first mounting part 140 in which the first electrode assembly 120 is accommodated and a second mounting part 142 in which the second electrode assembly 122 is mounted.

The first mounting part 140 is recessed downward from a part of the case body 112 in a shape corresponding to the first electrode assembly 120 , and the second mounting part 142 is the first mounting part 140 from one side of the first mounting part 140 . In a shape corresponding to the second electrode assembly 122 , it is recessed downward from a portion of the case body 112 .

The case body 112 is outwardly formed from the ends of each of the mounting parts except for the first fusion part 132 and the first fusion part 132 extending between the first mounting part 140 and the second mounting part 142 . It includes extended second fusion portions 134a, 134b, 134c, and 134d.

Reinforcing members (132a, 132b) extending from the end of the first fusion part 132 adjacent to the first fusion part 132 to the second mount part 142 and from the end of the first fusion part 132 to the other end direction adjacent to the first fusion part 132. this is fitted

The reinforcing members 132a and 132b have an outer surface surrounded by an insulating film, and during thermal fusion, the insulating film attached to the surface of the reinforcing members 132a and 132b is formed by the first fusion bonding portion 132 and the cover 114 . It can be heat-sealed between them.

The cover 114 is heat-sealed while in close contact with the first fusion part 132 and the second fusion parts 134a, 134b, 134c, and 134d formed on the upper portion of the case body 112, and the battery cell 100 is The deformable part 200 is formed in a region where the first fusion part 132 and the cover 114 are thermally fused, and the second fusion parts 134a, 134b, 134c, 134d and the cover 114 are thermally fused. The outer peripheral sealing portions (210a, 210b, 220a, 220b, 230a, 230b) are formed.

Accordingly, the battery cell 100 has a structure in which the first electrode assembly 120 and the second electrode assembly 122 are accommodated and sealed independently of each other together with the electrolyte in the battery case 110, and the variable type part ( 200), including the first unit cell 10 and the second unit cell 20 in which the first electrode assembly 120 is accommodated, and the second unit cell 20 and the first unit cell 10 ) between the deformable portion 200 is formed.

The reinforcing members 132a and 132b constitute a skeleton of the deformable part 200 between the first unit cell 10 and the second unit cell 10, so that the deformable part 200 is desired by gravity or other external force. to prevent deformation into shape.

That is, the reinforcing members 132a and 132b serve to provide resistance to the deformable parts 132a and 132b and maintain the shape of the deformable parts 132a and 132b after deformation.

The outer peripheral sealing parts (210a, 210b, 220a, 220b, 230a, 230b) are respectively extended from the front sealing parts (210a, 210b), the front sealing parts (210a, 210b) and formed on the side of the battery cell (100) It is formed at a position opposite to the side sealing parts 230a and 230b and the front sealing parts 210a and 210b, and includes rear sealing parts 220a and 220b extending between the side sealing parts 230a and 230b. do.

In the first unit cell 10, the anode lead 120a and the cathode lead 120b of the first electrode assembly 120 protrude side by side through the front sealing part 210a, and the second unit cell 20 is The anode lead 122a and the cathode lead 122b of the second electrode assembly 122 protrude side by side through another front sealing part 210b.

Accordingly, in the battery cell 100 shown in FIG. 4 , the electrode leads 120a, 120b, 122a, and 122b of the first unit cell 10 and the second unit cell 20 protrude side by side in the same direction. consists of structure.

The side sealing parts 230a and 230b are respectively bent in the indentation direction of the first mounting part 140 and the second mounting part 142 based on the reference lines A and A'.

As shown in FIGS. 5 to 8 , the battery cell 100 according to the present invention is a battery cell through the deformable part 200 formed between the first unit cell 10 and the second unit cell 20 . (100) may be transformed into various shapes from the basic shape (a) in which the first unit cell 10, the second unit cell 20, and the deformable part 200 are horizontal to each other.

First, referring to FIGS. 5 and 6 , in the battery cell 100 , in the basic form (a), the deformable part 200 is a part thereof in the direction of the second unit cell 20 with respect to the first unit cell 10 . may be bent downward to be transformed into a structure (b) including a slope.

When the deformable portion 200 is further bent from the structure (b), as in the structure (c), the first unit cell 10 and the second unit cell 20 are deformable to form a right angle to each other. In addition, from the structure (c), the deformable part 200 is vertically deformed with respect to the first unit cell 10 so that the first unit cell 10 and the second unit cell 20 form a step difference with each other (d) may be transformed into

Here, it should be noted that, in the battery cell 100 according to the present invention, the reinforcing members 132a and 132b provide a load to the deformable parts 132a and 132b to maintain the shape of the deformable deformable parts 132a and 132b. do.

Referring to FIG. 7 , in the battery cell 100 , in the basic form (a), the deformable part 200 is partially bent upward in the direction of the second unit cell 20 with respect to the first unit cell 10 to make the first battery cell 100 . When the first unit cell 10 and the second unit cell 20 can be transformed into a structure (e) at right angles to each other, and the deformable part 200 is further bent from the structure (d), the structure (f) and Similarly, the upper surface of the first unit cell 10 and the upper surface of the second unit cell 20 are in close contact with each other, it is possible to deform.

Of course, the battery cell 100 can be bent at any angle within the bending angle of the deformable part 200 from the structure (a) to the structure (f) to change the shape of the battery cell 100 , of course. .

8 schematically shows a structure in which the deformable part is deformed in a battery cell including three unit cells.

Referring to FIG. 8 , the battery cell 100a is each of the second unit cell 20a and the third unit cell 30a with respect to the first unit cell 10a so as to be easily embedded inside the cylindrical structure 1000 . It is rotated by these deformable parts 200a and 200b. Therefore, the battery cell 100a according to the present invention is deformed through the deformable parts 200a and 200b, and has a structure in which the space is narrow and is easily mounted in a space including a curved line rather than a flat plate type.

Meanwhile, FIG. 9 schematically shows a battery cell according to another embodiment of the present invention.

Referring to FIG. 9 , each of the first electrode assembly 410 and the second electrode assembly 420 includes positive leads 412 and 422 and negative leads 414 and 424 , and positive leads 412 and 422 . ) and the negative leads 414 and 424 have a structure protruding from both ends of the electrode assemblies 410 and 420, respectively.

Here, the anode lead 412 of the first electrode assembly 410 and the cathode lead 424 of the second electrode assembly 420 are electrically connected between the cover that is inside the deformable part 402 and the first fusion part. The furnace is positioned together with a reinforcing member (not shown), and the negative lead 414 of the first electrode assembly 410 protrudes to the outside of the battery cell 400 through the side sealing part 404, and the second electrode assembly The positive lead 422 of 420 protrudes to the outside of the battery cell 400 through another side sealing part 406 .

In the battery cell of this structure, since the electrode leads of the electrode assembly are connected between the first fusion part and the cover, when the deformable part is rotated or bent, the combined electrode leads are also rotated or bent together to serve as a reinforcing member. Also, since the electrical connection structure between the electrode assemblies is not formed outside the battery cell, it can have a more compact structure.

Unlike this, FIG. 10 schematically shows a structure of a battery cell in which electrode leads protrude through different outer circumferential sealing parts.

Referring to FIG. 10 , each of the first electrode assembly 510 and the second electrode assembly 520 includes positive electrode leads 512 and 522 and negative electrode leads 514 and 524 , and positive electrode leads 512 and 522 and The negative leads 512 and 522 have a structure protruding from both ends of the electrode assemblies 510 and 520 , respectively.

Here, the positive lead 512 of the first electrode assembly 510 protrudes to the outside through the first front sealing part 504a, and the negative lead 514 is externally through the first rear sealing part 504b. The anode lead 522 of the second electrode assembly 520 protrudes to the outside through the second front sealing part 506a, and the cathode lead 524 of the second electrode assembly 520 is the second It protrudes to the outside through the rear sealing part 506a.

In this structure, the cover and the case body are formed of independent members, and thus the electrode leads may protrude through all the outer circumferential sealing parts.

Similarly, FIG. 11 schematically shows another structure of a battery cell in which electrode leads protrude through different outer circumferential sealing parts.

Referring to FIG. 11 , each of the first electrode assembly 610 and the second electrode assembly 620 includes positive electrode leads 612 and 622 and negative electrode leads 614 and 724 , and positive electrode leads 612 and 622 and The negative leads 612 and 622 have a structure that protrudes side by side from one end of the electrode assemblies 610 and 620, respectively.

Here, the positive lead 612 and the negative lead 614 of the first electrode assembly 610 protrude side by side through the rear sealing part 604, and the positive lead 622 of the second electrode assembly 620. and the negative lead 624 protrude side by side through the front sealing part 606 to the outside.

12 and 13 are schematic plan views of case bodies constituting a battery cell according to still other embodiments of the present invention.

First, referring to FIG. 12 , the basic structure of the case body 700 is the same as that of the case body 112 shown in FIG. 3 , but the first fusion part 702 is first fused in the shape of an 'X' in plan view. Reinforcing members 710 and 712 having a structure extending from an end of the portion 702 toward the other end adjacent to another mounting portion are mounted.

The reinforcing members 710 and 712 include a metal plate and an electrical insulating film attached to the surface of the metal plate, and the insulating film may be thermally fused between the first fusion part 702 and the cover.

13 shows a reinforcing member having a different structure from this. Referring to FIG. 10 , the reinforcing member 810 has a concave-convex structure 812 that is recessed in a shape crossing the center to facilitate vertical bending.

In this structure, the stress applied to the deformable part of the battery case may be relieved while the reinforcing member 810 is easily deformed around the concave-convex structure 812 having a relatively thin thickness.

Those of ordinary skill in the art to which the present invention pertains will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

Claims (27)

and a battery case accommodating the electrode assemblies together with the electrolyte therein;
Two or more unit cells having a structure in which electrode assemblies are independently accommodated and sealed together with an electrolyte in the battery case, and the battery case are positioned between the unit cells in an extended state and pivotally rotated and/or bent It consists of a deformable part of the structure ;
The battery case is composed of a case body in which two or more mounting parts in which each of the electrode assemblies are accommodated, and a cover extending from one end of the case body or made of an independent member with respect to the case body, the case In a state in which the cover is in close contact with the body, at least a portion of the case body and the cover are heat-sealed and coupled to each other;
The case body includes a first fusion part extending between the mounting parts and second fusion parts extending outwardly from the ends of each of the mounting parts except for the first fusion part,
The first fusion part is thermally fused while the case body is in close contact with the cover to form a deformable part;
The deformable part is formed on one surface of the first fusion part facing the cover, and extends from an end of the first fusion part adjacent to the mounting part to the other end adjacent to another mounting part. At least two reinforcement members (reinforcement) comprising; The reinforcing member is a member that provides resistance to the deformable part when the deformable part is deformed and maintains the shape of the deformable part after deformation,
The reinforcing member is a metal plate, an electrically insulating film is attached to its surface, and adjacent to another mounting part from the end of the first fusion part in an 'X' shape on a plane so as to have rigidity in oblique bending. A battery cell, characterized in that it has a structure extending in the direction of the other end. at least two electrode assemblies each including a positive electrode, a negative electrode, and a separator, a non-aqueous electrolyte, and a battery case accommodating the electrode assemblies together with the electrolyte;
Two or more unit cells having a structure in which electrode assemblies are independently accommodated and sealed together with an electrolyte in the battery case, and the battery case are positioned between the unit cells in an extended state and pivotally rotated and/or bent It consists of a deformable part of the structure;
The battery case is composed of a case body in which two or more mounting parts in which each of the electrode assemblies are accommodated, and a cover extending from one end of the case body or made of an independent member with respect to the case body, the case In a state in which the cover is in close contact with the body, at least a portion of the case body and the cover are heat-sealed and coupled to each other;
The case body includes a first fusion part extending between the mounting parts and second fusion parts extending outwardly from the ends of each of the mounting parts except for the first fusion part,
The first fusion part is thermally fused while the case body is in close contact with the cover to form a deformable part;
The deformable part is formed on one surface of the first fusion part facing the cover, and extends from an end of the first fusion part adjacent to the mounting part to the other end adjacent to another mounting part. At least two reinforcement members (reinforcement) comprising; The reinforcing member is a member that provides resistance to the deformable part when the deformable part is deformed and maintains the shape of the deformable part after deformation,
The reinforcing member is a metal plate, and an electrical insulation film is attached to its surface, and a concave-convex structure recessed in a shape crossing the center is formed to facilitate vertical bending. The battery cell according to claim 1 or 2, wherein the battery case is made of a laminate sheet including a resin layer and a metal layer. The battery cell according to claim 1 or 2, wherein the mounting part has a structure that is depressed downward or upward from the case body in a shape corresponding to the electrode assembly. delete delete delete The battery cell according to claim 1 or 2, wherein the reinforcing member is a metal plate having a honeycomb structure. delete delete The battery cell according to claim 1 or 2, wherein the thickness of the reinforcing member is 100% to 1000% of the thickness of the first fusion part. The battery cell according to claim 1 or 2 , wherein the second fusion parts are thermally fused while the case body is in close contact with the cover to form outer periphery sealing parts of the battery cell. The method according to claim 1 or 2, wherein the portion where the electrode lead of one electrode assembly and the electrode lead of another electrode assembly adjacent to the electrode assembly are electrically connected is located between the cover inside the deformable part and the first fusion part. A battery cell, characterized in that. The battery cell according to claim 12, wherein each of the electrode assemblies has electrode leads projecting to the outside of the battery case through at least one of the outer circumferential sealing parts. 15. The battery cell according to claim 14, wherein in the electrode assemblies, their electrode leads each protrude through the same outer circumferential sealing part. 15. The battery cell according to claim 14, wherein in the electrode assemblies, their electrode leads protrude through different outer circumferential sealing parts. The battery cell according to claim 14, wherein, among the sealing parts, the remaining outer peripheral sealing parts from which the electrode leads do not protrude are bent in the direction of the mounting part. The battery cell according to claim 1 or 2 , wherein the first fusion part has a thickness of 50% to 90% compared to the thickness of the second fusion part. The battery cell according to claim 1 or 2 , wherein the width of the first fusion part is 10% to 100% of the width of one of the inner mounting parts. According to claim 1 or 2 , The battery cell,
n (n≥2) electrode assemblies include n unit cells connected to each other by deformable parts,
Based on the first unit cell, each of the second to nth unit cells is rotated by 0 degrees to 180 degrees by the deformable parts, and/or in the nth unit cell direction with respect to the first unit cell. A battery cell, characterized in that it has a bent structure. The battery cell according to claim 20, wherein the n-th unit cells independently supply power to different electric devices. The battery cell according to claim 20, wherein the n-th unit cells are connected in series and/or in parallel with adjacent unit cells from the first unit cell to the n-th unit cell. The method of claim 20, wherein the electrode assembly is a jelly-roll type electrode assembly of a structure wound with a separation sheet interposed between the positive electrode sheet and the negative electrode sheet, and the unit cell is a plate-shaped (plate-) shaped) battery cell, characterized in that it has a structure. As a method for manufacturing the battery cell according to claim 1 or 2,
(a) the process of mounting each of the electrode assemblies to the mounting parts of the battery case;
(b) injecting an electrolyte into each mounting part;
(c) forming an outer periphery sealing part by attaching the case body and the cover of the battery case to close contact, and heat-sealing the second fusion parts; and
(d) forming a deformable part by heat-sealing the first fusion part;
A method comprising a. A battery pack comprising at least one battery cell according to claim 1 or 2 . One or more devices using the battery pack according to claim 25 as a power source. The device of claim 26, wherein the device is a mobile electronic device, a wearable electronic device, an unmanned aerial vehicle, or an electric bicycle.

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