KR20160049709A - Apparatus Transferring Battery Cell - Google Patents

Abstract

The present invention relates to a battery cell transfer apparatus having a belt allowing a battery cell to be transferred while being seated in a process of manufacturing a plate-shaped battery cell capable of being charged/discharged. The belt of the battery cell transfer apparatus comprises: at least two fixing bars for separating a space in which a battery cell is seated; and a guide member for fixing the location of the battery cell; and at least one vacuum pad which is formed on the upper side of the belt facing one side of the battery cell, is absorbed in and adhered to one side of the seated battery cell, and fixes the battery cell at a right place. The battery cell transfer apparatus of the present invention can precisely realize the appearance of a battery cell by basically preventing the battery cell from moving in a transfer process, thereby enhancing process efficiency.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a battery cell transfer device.

As technology development and demand for mobile devices are increasing, the demand for batteries as energy sources is rapidly increasing, and accordingly, a lot of researches on batteries capable of meeting various demands have been conducted.

In recent years, there has been a growing interest in environmental issues, and as a result, electric vehicles (EVs) and hybrid electric vehicles (HEVs), which can replace fossil-fueled vehicles such as gasoline vehicles and diesel vehicles, And the like. Although a nickel metal hydride (Ni-MH) secondary battery is mainly used as a power source for such an electric vehicle (EV) and a hybrid electric vehicle (HEV), a lithium secondary battery having a high energy density, a high discharge voltage, Research is being actively carried out, and some are commercialized.

Furthermore, in recent years, due to the miniaturization and diversification of such secondary batteries, various forms of secondary batteries are required to be realized according to the internal usage environment of external devices.

However, since the battery cells of various shapes are required to be highly accurate, the battery cells that are seated on the belt during the process of manufacturing the battery cells may flow in a minute flow, There arises a problem that one end is turned off.

Accordingly, there is a high need for a battery cell transfer device capable of stably performing necessary shape processing even when the battery cell is moved during the manufacturing process of the battery cell.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

It is an object of the present invention to provide a method of manufacturing a battery cell in which a separate vacuum pad is formed on a belt on which a battery cell is placed to prevent the battery cell from flowing during the transfer, The shape of the battery cell can be formed at an accurate position.

It is still another object of the present invention to provide a hot press having a specific structure capable of stably pressing the outer surface of a battery cell having variously shaped recesses.

In order to accomplish the above object, according to the present invention, there is provided a battery cell transferring apparatus comprising a battery cell having a belt which is conveyed while a battery cell is placed in a process of manufacturing a charge / A transfer device, comprising:

At least two fixing bars for defining a space in which the battery cell is seated;

A guide member for fixing the position of the battery cell; And

At least one vacuum pad formed on an upper surface of the belt facing one surface of the battery cell, the at least one vacuum pad sucked on one surface of the mounted battery cell to fix the battery cell in place;

.

That is, the vacuum pad is adsorbed on one surface of the battery cell to fix the battery cell, thereby preventing the battery cell from flowing during the battery cell manufacturing process. In addition, even when a recess is formed in a certain portion of the battery case using a hot press described below, it is possible to perform accurate shape processing.

The battery case of the battery cell is not particularly limited, but may be at least one selected from the group consisting of a laminate sheet including a resin layer and a metal layer, and a rectangular metal can. In consideration of the weight of the secondary battery itself, it is preferable to use a battery case made of a laminate sheet.

In one preferred example, the laminate sheet may have a laminated structure of an outer resin layer, an air and moisture barrier metal layer, and a heat-sealable inner resin layer.

The battery case may have a structure in which an outer circumferential portion of the electrode assembly receiving portion is thermally fused in a state in which the electrode assembly is embedded. In a specific example, the electrode assembly may have a winding structure, a stack structure, a stack / And a laminate / stack type structure.

For reference, the structures of the stacked type, the stacked / folded type, and the lamination / stacked type will be described in detail as follows.

First, the electrode assembly of the stacked structure is manufactured by coating each electrode collector with an electrode material mixture, drying and pressing, and then cutting the electrode assembly into a predetermined size corresponding to the positive electrode plate and the negative electrode plate between the positive electrode plate and the negative electrode plate, And then a separator is interposed therebetween and then laminated.

The electrode assembly of the stack / folding type structure includes two or more unit cells having a structure in which an anode and a cathode face each other and in which two or more electrode plates are stacked, and the unit cells are wound in one non- Or by bending the separation film to a size of the unit cell and interposing it between the unit cells.

The electrode assembly of the lamination / stacked structure is obtained by coating each metal current collector with an electrode mixture, drying, pressing and cutting to a predetermined size, sequentially separating the negative electrode from the lower portion, And a separator is laminated thereon.

In one specific example, the battery cell may have a structure in which an engraved groove is formed in a part thereof. The battery cell having such a structure has a structure in which a recess is formed in a necessary shape in a battery case according to an internal environment when the battery cell is mounted on an external device, The electrode assembly corresponding portion is a unit cell (a full cell of a unit cell of a unit size, a separator / cathode structure or a bicell of a structure of a cathode / a separator / a cathode / a separator / Is removed by the depth of the groove. For example, in the electrode assembly in which ten unit pieces are stacked, the grooved portion is formed by stacking eight unit pieces.

In some cases, on the contrary, it may be formed in a structure in which the battery cell has a protruding relief shape.

The battery cell may have a structure in which the electrode terminals protrude in one direction or in opposite directions.

In one specific example, the belt may be formed in two or more rows in the vertical direction with respect to the electrode terminals of the battery cell.

In the above structure, the vacuum pad may be formed in each of the facing portions where the belt and the battery cell are in contact with each other.

In a specific example, the size of the vacuum pad is formed to be 10 to 50% of the width of the battery cell, and is formed at a portion spaced within a range of 3 to 30 mm from the upper or lower end with respect to the long axis of the battery cell Lt; / RTI >

The vacuum pad may be formed on a virtual vertical line passing through the center of the battery cell in a direction parallel to the electrode terminal of the battery cell.

The present invention includes the battery cell transfer apparatus and a battery cell manufacturing apparatus including a hot press for heating and pressing the battery cell transferred from the battery cell transfer apparatus.

According to the present invention, the hot press is provided with a plurality of recesses corresponding to the outer surface of the battery cell having the depressed grooves formed therein, The upper surface of the battery cell and the groove can be pressed and heated at the same time by forming a protruding pressing portion of the same shape.

In some cases, as described above, in the case of a structure in which a protruding relief is formed on the battery cell, a groove having a corresponding shape may be formed in the hot press.

The present invention provides a battery cell manufactured using the battery cell transfer device. The battery cell may be a lithium secondary battery having a structure in which a nonaqueous electrolyte solution containing a lithium salt is impregnated in an electrode assembly having a separator interposed between an anode and a cathode.

Generally, the positive electrode of such a secondary battery is prepared, for example, by applying a positive electrode mixture containing a positive electrode active material on a positive electrode collector and then drying the positive electrode mixture. The positive electrode mixture may contain a binder, A filler, and the like may be optionally included.

The cathode current collector generally has a thickness of 3 to 500 mu m. Such a positive electrode current collector is not particularly limited as long as it has high conductivity without causing chemical change in the battery, and may be formed of a material such as stainless steel, aluminum, nickel, titanium, sintered carbon, or a surface of aluminum or stainless steel Treated with carbon, nickel, titanium, silver or the like may be used. The positive electrode current collector may have fine unevenness formed on the surface thereof to increase the adhesive force of the positive electrode active material as in the case of the negative electrode current collector. Alternatively, the positive electrode current collector may have various properties such as a film, sheet, foil, net, porous body, Form is possible.

The cathode active material is a material capable of causing an electrochemical reaction. Examples of the lithium transition metal oxide include lithium cobalt oxide (LiCoO ₂ ) containing two or more transition metals and substituted with one or more transition metals, lithium Layered compounds such as nickel oxide (LiNiO ₂ ); Lithium manganese oxide substituted with one or more transition metals; Formula _{LiNi 1-y M y O 2} ( where, M = Co, Mn, Al , Cu, Fe, Mg, B, Cr, Zn or Ga and Lim, 0.01≤y≤0.7 include one or more elements of the element) A lithium nickel-based oxide represented by the following formula: _{Li 1 + z Ni 1/3 Co 1/3} Mn 1/3 O 2, Li 1 + z Ni 0.4 Mn 0.4 Co 0.2 O 2 , such as _{Li 1 + z Ni b Mn c} Co 1- (b + c + d _{) M d O (2-e} ) A e ( where, -0.5≤z≤0.5, 0.1≤b≤0.8, 0.1≤c≤0.8, 0≤d≤0.2 , 0≤e≤0.2, b + c + d <1, M = Al, Mg, Cr, Ti, Si or Y, and A = F, P or Cl; lithium nickel cobalt manganese composite oxide; And the formula _{Li 1 + x M 1-y} M 'y PO 4-z X z ( wherein, M = a transition metal, preferably Fe, Mn, Co or Ni, M' = Al, Mg or Ti, X = F, S or N, and -0.5? X? +0.5, 0? Y? 0.5, and 0? Z? 0.1), but the present invention is not limited thereto.

The conductive material is usually added in an amount of 1 to 30% by weight based on the total weight of the mixture including the cathode active material. Such a conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes 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 fiber and metal fiber; Metal powders such as carbon fluoride, aluminum, and nickel powder; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Conductive materials such as polyphenylene derivatives and the like can be used.

The binder is a component which assists in bonding of the active material and the conductive material and bonding to the current collector, and is usually added in an amount of 1 to 30% by weight based on the total weight of the mixture containing the cathode 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 butylene rubber, fluorine rubber, and various copolymers.

The filler is optionally used as a component for suppressing the expansion of the electrode, and is not particularly limited as long as it is a fibrous material without causing any chemical change in the battery. Examples of the filler include olefin-based polymerizers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

The negative electrode is prepared, for example, by applying a negative electrode mixture containing a negative electrode active material on a negative electrode collector and then drying the same. The negative electrode mixture may contain a conductive material, a binder, a filler, May be included.

The negative electrode collector is generally made to have a thickness of 3 to 500 mu m. The negative electrode current collector is not particularly limited as long as it has high conductivity without causing chemical change in the battery. Examples of the negative electrode current collector include copper, stainless steel, aluminum, nickel, titanium, sintered carbon, copper or stainless steel Surface-treated with carbon, nickel, titanium, silver or the like, aluminum-cadmium alloy, or the like can be used. In addition, like the positive electrode collector, fine unevenness can be formed on the surface to enhance the bonding force of the negative electrode active material, and it can be used in various forms such as films, sheets, foils, nets, porous bodies, foams and nonwoven fabrics.

The negative electrode active material may include, for example, carbon such as non-graphitized carbon or graphite 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 complex oxides such as Al, B, P, Si, Group 1, Group 2, Group 3 elements of the periodic table, Halogen, 0 < x &lt; Lithium metal; Lithium alloy; Silicon-based alloys; Tin alloy; _{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, Bi ₂ O ₅ and the like; Conductive polymers such as polyacetylene; Li-Co-Ni-based materials and the like can be used.

The binder, the conductive material, and the components added as needed are the same as those in the anode.

In some cases, a filler may be optionally added as a component to suppress the expansion of the negative electrode. Such a filler is not particularly limited as long as it is a fibrous material without causing a chemical change in the battery, and examples thereof include olefin polymers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

In addition, other components such as a viscosity adjusting agent, an adhesion promoter and the like may be further included as a selective or a combination of two or more.

The viscosity modifier may be added up to 30% by weight based on the total weight of the negative electrode mixture as a component for adjusting the viscosity of the electrode mixture so that the mixing process of the electrode mixture and the coating process on the current collector may be easy. Examples of such viscosity modifiers include carboxymethylcellulose, polyvinylidene fluoride and the like, but are not limited thereto. In some cases, the above-described solvent may play a role as a viscosity adjusting agent.

The adhesion promoter may be added in an amount of 10% by weight or less based on the binder, for example, oxalic acid, adipic acid, Formic acid, acrylic acid derivatives, itaconic acid derivatives, and the like.

The separation membrane 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 mu m, and the thickness is generally 5 to 300 mu m. Such separation membranes include, for example, olefinic polymers such as polypropylene, which are chemically resistant and hydrophobic; A sheet or nonwoven fabric made of glass fiber, polyethylene or the like is used. When a solid electrolyte such as a polymer is used as an electrolyte, the solid electrolyte may also serve as a separation membrane.

The lithium salt-containing nonaqueous electrolyte solution is composed of an electrolyte solution and a lithium salt. As the electrolyte solution, a nonaqueous organic solvent, an organic solid electrolyte, and an inorganic solid electrolyte may be used.

Examples of the non-aqueous organic solvent include N-methyl-2-pyrrolidinone, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, gamma -Butyrolactone, 1,2-dimethoxyethane, tetrahydroxyfuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,3-dioxolane, formamide, dimethylformamide, dioxolane , Acetonitrile, nitromethane, methyl formate, methyl acetate, triester phosphate, trimethoxymethane, dioxolane derivatives, sulfolane, methylsulfolane, 1,3-dimethyl-2-imidazolidinone, propylene carbonate Nonionic organic solvents such as tetrahydrofuran derivatives, ethers, methyl pyrophosphate, ethyl propionate and the like can be used.

Examples of the organic solid electrolyte include a polymer electrolyte such as a polyethylene derivative, a polyethylene oxide derivative, a polypropylene oxide derivative, a phosphate ester polymer, an agitation lysine, a polyester sulfide, a polyvinyl alcohol, a polyvinylidene fluoride, A polymer containing an ionic dissociation group and the like may 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 and sulfates of Li such as Li ₄ SiO ₄ -LiI-LiOH and Li ₃ PO ₄ -Li ₂ S-SiS ₂ can be used.

The lithium salt is a material that is readily 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 2) 2 NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenyl borate and imide.

For the purpose of improving the charge / discharge characteristics and the flame retardancy, the electrolytic solution is preferably mixed with an organic solvent such as pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, glyme, Benzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N, N-substituted imidazolidines, ethylene glycol dialkyl ethers, ammonium salts, pyrrole, 2-methoxyethanol, . In some cases, halogen-containing solvents such as carbon tetrachloride and ethylene trifluoride may be further added to impart nonflammability. In order to improve the high-temperature storage characteristics, carbon dioxide gas may be further added. FEC (Fluoro-Ethylene Carbonate, PRS (Propene sultone), and the like.

The present invention also provides a battery module including the battery cell as a unit cell, and a battery pack including the battery module.

The battery pack may be used as a power source for devices requiring high temperature stability, long cycle characteristics, and high rate characteristics.

Preferred examples of the device include a notebook, a mobile phone, a PDP, a PMP, an MP3 player, a DSC (digital still camera), a DVR, a smart phone, a GPS system, a camcorder, an electric vehicle, a hybrid electric vehicle, Apparatus, and the like, but is not limited thereto.

As described above, in the case of using the battery cell transferring apparatus according to the present invention, it is possible to fundamentally prevent the flow of the battery cell in the process of transferring the battery cell, have.

In addition, when the hot press according to the present invention is used, the battery cell having grooves of various shapes and sizes can be produced by effectively pressing and heating.

1 is a schematic diagram of a conventional conventional battery cell conveying apparatus;
2 is a perspective view of a refuge battery cell including a stacked electrode assembly according to the present invention;
3 is a schematic view of a battery cell transferring device according to the present invention;
4 is a perspective view of a hot press according to the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited by the scope of the present invention.

2 is a perspective view of a pouch battery including a stacked electrode assembly according to the present invention.

Referring to these figures, the battery cell 100 includes an electrode assembly 120 including an anode, a cathode, and a separator disposed between the anode and the cathode, and the electrode tabs 121 are welded to the two electrode leads 122 to be exposed to the outside of the battery case 110.

The battery case 110 is made of a soft packaging material such as an aluminum laminate sheet and includes a case body 111 including a concave shaped storage portion 113 on which the electrode assembly 120 can be placed, And a lid 112 to which one side is connected.

The electrode assembly 120 used in the battery cell 100 may have a jelly-roll structure other than the stacked structure. The stacked electrode assembly 120 includes a plurality of electrode tabs 121 welded to the electrode leads 122. The electrode leads 122 are electrically connected to the battery case 110 by insulation The film 123 is attached to the upper and lower surfaces.

FIG. 3 schematically shows a battery cell transfer device according to the present invention, and FIG. 4 schematically shows a perspective view of a hot press device according to the present invention.

2, the battery cell transfer device includes a pouch-shaped battery cell 100 having electrode terminals 122 formed thereon, a pair of paired battery cells 100 that are moved in one direction in a state where the battery cell 100 is seated, And a guide member 120 for fixing the positions of the belts 30 and 31 and the battery cell 110. [

The belts 30 and 31 are formed in two rows in the vertical direction to the electrode terminals 122 of the battery cells 100 and the battery cells 100 are formed in the two rows of the belts 30 and 31 And is seated in a state of being spread over the upper and lower ends. A plurality of fixing bars 31 for fixing the positions of the battery cells 100 are attached to the belts 30 and 31 in a direction perpendicular to the moving direction of the battery cells 100 The slider 121 of the guide member 120 is drawn out between the electrode terminals 122 of the battery cells 100 to fix the position of the battery cells 100. [

Vacuum pads 300 are formed on the imaginary vertical line A passing through the center of the battery cell 100 in the direction parallel to the electrode terminal 122 of the battery cell 100 on the belts 30 and 31 have. The vacuum pads 300 are formed to have a size of 30% with respect to the width W of the battery cell 100 and have a length L of 10 mm from the upper or lower end of the battery cell 100, Are formed at the spaced apart portions.

Accordingly, in the battery cell manufacturing process, since the back surface of the battery cells 100, which are seated on the upper surface of the belts 30 and 31, is firmly fixed by the vacuum pads 300, Can be stably formed at an accurate position.

The pressurization and heating process of the outer surface of the battery cell 100 is facilitated by the hot press 500 in which the pressing portion 510 having the shape and size corresponding to the outer shape of the battery cell 100 formed with the groove 200 is formed .

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (19)

There is provided a battery cell conveying apparatus comprising a belt which is conveyed in a state in which a battery cell is placed in a process of manufacturing a plate-shaped battery cell capable of charging and discharging,
At least two fixing bars for defining a space in which the battery cell is seated;
A guide member for fixing the position of the battery cell; And
At least one vacuum pad formed on an upper surface of the belt facing one surface of the battery cell, the at least one vacuum pad sucked on one surface of the mounted battery cell to fix the battery cell in place;
The battery cell transferring device comprising: The battery cell conveying apparatus according to claim 1, wherein the battery case of the battery cell comprises a laminate sheet including a resin layer and a metal layer. 3. The battery cell conveying apparatus according to claim 2, wherein the laminate sheet has a laminated structure of an outer resin layer, an air and moisture barrier metal layer, and a heat-sealable inner resin layer. The battery cell transferring apparatus according to claim 2, wherein the battery case has an outer peripheral portion of the electrode assembly receiving portion thermally fused with the electrode assembly being embedded therein. The apparatus of claim 1, wherein the electrode assembly comprises a wrapping structure, a stacking structure, a stacking / folding structure, or a lamination / stacking structure. The battery cell transfer apparatus according to claim 1, wherein the battery cell has a recess formed in a part thereof. The battery cell conveying apparatus according to claim 1, wherein the battery cell has a structure in which electrode terminals protrude in one direction or in an opposite direction. The battery cell conveying apparatus according to claim 1, wherein the belt is formed in two or more rows in a direction perpendicular to the electrode terminals of the battery cell. The battery cell conveying apparatus according to claim 8, wherein the vacuum pads are formed at respective facing portions where the belt and the battery cell contact each other. The apparatus of claim 1, wherein a size of the vacuum pad is 10 to 50% of a width of the battery cell. 2. The battery cell conveying apparatus according to claim 1, wherein the vacuum pads are formed at a position spaced within a range of 5 to 20 mm from an upper end or a lower end with respect to a long axis of the battery cell. The battery cell feeder according to claim 1, wherein the vacuum pad is formed on a virtual vertical line passing through the center of the battery cell in a direction parallel to the electrode terminal of the battery cell. 13. A battery cell manufacturing apparatus comprising: the battery cell conveying device according to any one of claims 1 to 12; and a hot press for heating and pressing the battery cell transferred from the battery cell conveying device. A battery cell characterized by being manufactured using the apparatus according to claim 13. 15. The secondary battery according to claim 14, wherein the battery cell is a lithium secondary battery. 15. A battery module comprising the battery cell according to claim 14 as a unit cell. A battery pack comprising the battery module according to claim 16. A device according to claim 17, wherein the battery pack is used as a power source. 19. The device of claim 18, wherein the device is a notebook, a mobile phone, a PDP, a PMP, an MP3 player, a DSC (Digital Still Camera), a DVR, a smartphone, a GPS system, a camcorder, an electric vehicle, a hybrid electric vehicle, And a power storage device.

Images