KR102000539B1 - Method of Manufacturing Electrode Plate Using Unit Electrode Sheet Including Coating Portions Having Different Size from One Another - Google Patents

Abstract

A method of manufacturing an electrode plate for a secondary battery, comprising the steps of: (a) preparing a unit electrode sheet including a first coating portion, a second coating portion, and a non-coated uncoated portion on at least one surface of a unit current collector sheet; And (b) a step of notching the non-coated portion in the shape of a first electrode tab and a second electrode tab, the non-coated portion being located between the first coated portion and the second coated portion, And second coating portions are different in area from each other.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an electrode plate for a secondary battery using a unit electrode sheet including coating portions having different areas,

The present invention relates to a method of manufacturing an electrode plate for a secondary battery using a unit electrode sheet including coating portions having different areas.

Due to the rapid increase in the use of fossil fuels, the demand for the use of alternative energy or clean energy is increasing. As a part of this, the most active field of research is electric power generation and storage.

At present, a typical example of an electrochemical device utilizing such electrochemical energy is a secondary battery, and the use area thereof is gradually increasing.

The secondary battery is classified into a cylindrical battery and a prismatic battery in which the electrode assembly is housed in a cylindrical or rectangular metal can according to the shape of the battery case, and a pouch-shaped battery in which the electrode assembly is housed in a pouch-shaped case of an aluminum laminate sheet .

The electrode assembly incorporated in the battery case is a charge / dischargeable power generating element formed of a laminate structure of a positive electrode / separator / negative electrode. The electrode assembly is composed of a jelly-roll type in which a separator is interposed between a positive electrode and a negative electrode coated with an active material, Sized positive and negative electrodes are stacked in a stacked state in a state in which a separator is interposed therebetween.

A full cell or anode / separator / cathode / separator / separator / separator / cathode assembly having a positive electrode / separator / negative electrode structure with a constant unit size, which is a progressive structure of a jelly- A stack / folding type electrode assembly having a structure in which a bicell having a positive (negative) electrode structure is folded by using a continuous long separating film has been developed.

Further, in order to improve the processability of the conventional stacked electrode assembly and meet the demands of various types of secondary batteries, a lamination / stacked electrode structure in which unit cells alternately laminated and laminated are laminated Assemblies have also been developed.

On the other hand, in recent years, the design of the electronic device itself is a very important factor in selecting the product of the consumer, and the electronic device is gradually becoming smaller and thinner depending on the taste of the consumer. Accordingly, in order to minimize the unnecessary waste of the internal space of the electronic device, the lithium secondary battery is also required to be downsized and thinned, and the shape of the lithium secondary battery also needs to be variously implemented according to the shape of the electronic device.

Reflecting this trend, a step-like battery was developed as a lithium secondary battery mounted on the curved portion of the device. In order to manufacture a step-like battery, it is essential to manufacture and laminate electrode plates or unit cells having different areas. In order to manufacture an electrode plate or a unit cell having different areas, a collector sheet and a metal mold for manufacturing each electrode plate or a unit cell are required, so that the manufacturing process becomes complicated, the cost of the raw material increases, There is a problem of rising.

Therefore, even if an electrode plate or a unit cell having a different area is manufactured, there is a high need for a technique capable of reducing the manufacturing cost while simplifying the manufacturing process.

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.

The inventors of the present application have conducted intensive research and various experiments, and have found that, as will be described later, the unit electric collector sheet is provided with a first coating portion, a second coating portion, and a non- In manufacturing the sheet, the non-coated portion is located between the first coated portion and the second coated portion, and when the areas of the first coated portion and the second coated portion are different from each other, the manufacturing process can be simplified and the manufacturing cost can be reduced And have completed the present invention.

Accordingly, a method of manufacturing an electrode plate for a secondary battery according to the present invention includes:

(a) fabricating a unit electrode sheet including a first coating portion, a second coating portion, and a non-coated uncoated portion on at least one side of a unit current collector sheet; And

(b) notching the non-coated portion in a shape of a first electrode tab and a second electrode tab; Wherein the uncoated portion is located between the first coating portion and the second coating portion, and the areas of the first coating portion and the second coating portion are different from each other.

Here, the first coating portion and the second coating portion refer to a coating portion of an electrode mixture containing an electrode active material, and the electrode includes a cathode and an anode.

The unit current collector sheet means a current collector sheet corresponding to the unit electrode sheet immediately before the electrode plate is produced through notching.

According to the conventional electrode plate manufacturing method, only one type of electrode plate having the same area of the coating portion from one unit electrode sheet can be manufactured. In the case of a general secondary battery using only one type of electrode plate having substantially the same area, it was effective to manufacture the electrode plate by such a manufacturing method.

However, in the case of a step-like secondary battery, two or more electrode plates having different areas are required. Therefore, when only one kind of electrode plate having the same area from one unit electrode sheet is produced, necessary manufacturing equipment is increased, There is a problem that various kinds of sheets are required and manufacturing cost increases.

Specifically, in order to produce one kind of electrode plate, a mold of a coating apparatus for applying an electrode active material is required, and a notching die is required according to the area of the coating portion and the size of the electrode tab. Further, The size of the unit collector sheet varies depending on the area of the area. Therefore, in order to manufacture two types of electrode plates having different areas, the production cost of the mold and the notching mold of the coating apparatus is doubled, the period for manufacturing such a mold is also longer, As a result, the manufacturing cost of the electrode plate is remarkably increased.

According to the manufacturing method of the present invention, two types of electrode plates having different areas can be manufactured by using one unit current collector sheet, so that only one kind of mold of the coating apparatus and a notching mold are required, The manufacturing cost of the mold can be reduced to half, and the production cost of the unit current collector sheet is not limited to the step-type secondary battery, The manufacturing cost of the secondary battery can be reduced to the level.

It is not possible to form three or more coating portions having different areas on the unit current collector sheet. However, in this case, the arrangement of the coating portions and the non-coating portions becomes complicated, and the notching process becomes complicated, And the process efficiency may be lowered.

Meanwhile, in the above-described manufacturing method, a double-sided electrode plate on which electrode active materials are applied on both sides of a unit current collector sheet as well as a single-sided electrode plate on which electrode active material is applied to only one side of the unit current collector sheet can be manufactured.

In one specific example, the unit electrode sheet including the first coating portion, the second coating portion and the non-coated portion may be manufactured on both sides of the unit current collector sheet in the process (a).

In the case of manufacturing the double-sided electrode plate, the first coating portion, the second coating portion, and the non-coated portion are symmetrically positioned on both sides of the unit current collector sheet to increase the efficiency in performing a process such as notching, .

In one specific example, in the step (b), the first electrode tab may be formed in a structure extending from the current collector of the first coating portion, and the second electrode tab may be formed in a structure extending from the second coating portion .

Thus, the process of welding the electrode tab and the current collector can be omitted through the structure in which the electrode tab extends from the collector of the coating portion, and the electrical resistance at the connection portion between the electrode tab and the current collector can be reduced.

The first coating unit and the second coating unit may have a structure in which the lengths of the first and second coating units are equal to each other and the widths thereof are different from each other when the relatively long sides of the unit current collector sheet are transversely shortened and the short sides thereof are longitudinal.

When the lengths of the first coating part and the second coating part are the same, it is possible to vary the area by adjusting the width of the first coating part and the second coating part, Therefore, the manufacturing process can be simplified.

In one specific example, the process (a) may comprise the following (a1) to (a3):

(a1) preparing an electrode sheet by applying an electrode active material to a current collector sheet so that the structure of the unit electrode sheet including the first coating portion, the second coating portion and the non-coated portion is formed in at least two units, and drying the electrode active material;

(a2) rolling the electrode sheet; And

(a3) slitting the rolled electrode sheet in unit electrode sheet units.

At this time, the electrode sheet refers to a sheet having a structure in which each unit electrode sheet is manufactured through slitting and includes two or more unit electrode sheets in one repeating unit.

In the case where the first coating portion and the second coating portion are separately formed and separately formed, the uncoated portion should be positioned between the first coating portion and the second coating portion. In this case, the collector sheet may be wasted by the area of the non- In addition, since a single application must be further performed in the coating process, the manufacturing process can be complicated.

Thus, in one specific example, in the process (a1), the electrode sheet has the same length as the first coating portion and the second coating portion, and the width of the first coating portion and the width of the second coating portion are And a third coating portion having a horizontal length of a combined size.

Further, in the step (a3), the third coating part may be slitted to form the first coating part and the second coating part of different unit electrode sheets.

In this case, since the first coating portion and the second coating portion of the different unit electrode sheets can be formed by one slitting, the number of times of slitting can be reduced, and the manufacturing cost can be reduced.

The present invention also provides a unit electrode sheet capable of producing two electrode plates by notching,

Wherein the unit electrode sheet includes a first coating portion, a second coating portion, and an uncoated non-coated portion in which an electrode active material is coated on at least one surface of the unit current collector sheet, the non-coated portion including a first coating portion and a second coating And the first coating portion and the second coating portion may have a different area from each other.

In one specific example, the non-coated portion is notched in the shape of a first electrode tab and a second electrode tab, and the first electrode tab is formed to have a structure extending from the current collector of the first coated portion, The tab may be formed in a structure extending from the current collector of the second coating portion.

The first electrode tab and the second electrode tab can be manufactured from the non-coated portion, so that it is not necessary to form two uncoated portions for producing the electrode tab, and the current collector sheet can be saved.

The present invention also provides an electrode sheet capable of producing a plurality of unit electrode sheets by slitting,

The electrode sheet may have a structure including two or more units of the unit electrode sheet. The unit electrode sheet may include a first coating portion coated with an electrode active material on at least one surface of the unit current collector sheet, And an uncoated uncoated portion, wherein the uncoated portion is positioned between the first coated portion and the second coated portion, and the first coated portion and the second coated portion may have a different area from each other.

In one specific example, the electrode sheet has a length equal to that of the first coating portion and the second coating portion, and has a width of the first coating portion and a width of the second coating portion, 3 coating. ≪ / RTI >

The present invention also provides an electrode plate for a secondary battery, manufactured by the above method, having a size corresponding to the first coating portion or the second coating portion, wherein the electrode plate for a secondary battery of a size corresponding to the first coating portion, And the electrode plate for a secondary battery of a size corresponding to the second coating portion.

Hereinafter, other components of the secondary battery will be described.

The positive electrode may be prepared, for example, by applying a positive electrode mixture mixed with a positive electrode active material, a conductive material and a binder to a positive electrode collector, and if necessary, a filler may further be added to the positive electrode mixture.

The cathode current collector is generally formed to a thickness of 3 to 201 탆 and is not particularly limited as long as it has high conductivity without causing chemical change in the battery. For example, stainless steel, aluminum, nickel, titanium , And a surface treated with carbon, nickel, titanium or silver on the surface of aluminum or stainless steel can be used. Specifically, aluminum can be used. The current collector may have fine irregularities on the surface thereof to increase the adhesive force of the cathode active material, and various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric are possible.

The cathode active material may be, for example, a layered compound such as lithium cobalt oxide (LiCoO ₂ ) or lithium nickel oxide (LiNiO ₂ ) or a compound substituted with one or more transition metals; Lithium manganese oxides such as Li _{1 + x} Mn _{2 -x} O ₄ (where x is 0 to 0.33), LiMnO ₃ , LiMn ₂ O ₃ , LiMnO ₂ and the like; Lithium copper oxide (Li ₂ CuO ₂ ); Vanadium oxides such as LiV ₃ O ₈ , LiV ₃ O ₄ , V ₂ O ₅ and Cu ₂ V ₂ O ₇ ; A Ni-site type lithium nickel oxide expressed by the formula LiNi _1-x M _x O ₂ (where 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, and Zn, or Ta, x = 0.01 ~ 0.1 Im) or Li ₂ Mn ₃ MO ₈ (where, M = Fe, Co, 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; Fe ₂ (MoO ₄ ) ₃ , and the like. However, the present invention is not limited to these.

The conductive material is usually added in an amount of 1 to 30% by weight based on the total weight of the positive electrode material mixture containing the positive electrode 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 contained in the positive electrode is added to the binder in an amount of 1 to 30% by weight, based on the total weight of the mixture containing the positive electrode active material, as a component that assists in bonding between the active material and the conductive material and bonding to the current collector. 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-butadiene rubber, fluorine rubber, various copolymers and the like.

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

On the other hand, the negative electrode may be manufactured by applying a negative electrode mixture containing a negative electrode active material, a conductive material, and a binder to a negative electrode collector, and a filler or the like may further be optionally included.

The negative electrode current collector is not particularly limited as long as it has electrical conductivity without causing a chemical change in the battery. For example, the negative electrode current collector may be formed on the surface of copper, stainless steel, aluminum, nickel, titanium, sintered carbon, Carbon, nickel, titanium, silver or the like, an 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.

In the present invention, the thickness of the anode current collector may be the same within the range of 3 to 201 [mu] m, but may have different values depending on the case.

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, and Bi ₂ O ₅ ; Conductive polymers such as polyacetylene; Li-Co-Ni-based materials and the like can be used.

In one specific example, the separation membrane may be a polyolefin-based film commonly used in the art, and may be, for example, high density polyethylene, low density polyethylene, linear low density polyethylene, ultra high molecular weight polyethylene, polypropylene, polyethylene terephthalate polyethyleneterephthalate, polybutyleneterephthalate, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyetheretherketone, A sheet made of at least one selected from the group consisting of polyethersulfone, polyphenylene oxide, polyphenylenesulfrode, polyethylene naphthalene, and mixtures thereof.

The separation membrane may be made of the same material but is not limited thereto and may be made of materials different from each other depending on safety, energy density, and overall performance of the battery cell.

The pore size and porosity of the separation membrane are not particularly limited, but the porosity may be in the range of 10 to 95% and the pore size (diameter) may be 0.1 to 50 탆. When the pore size and porosity are 0.1 μm or less and 10% or less, respectively, it acts as a resistive layer. If the pore size and porosity are more than 50 μm and 95%, it is difficult to maintain the mechanical properties.

The electrolyte solution may be a non-aqueous electrolyte containing a lithium salt, and the non-aqueous electrolyte containing a lithium salt is composed of a non-aqueous electrolyte and a lithium salt. Non-aqueous organic solvents, organic solid electrolytes, inorganic solid electrolytes, The present invention is 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 -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 derivatives, Tetrahydrofuran derivatives, ether, 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 acid 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 substance that is soluble in the nonaqueous electrolyte and includes, 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 carboxylate lithium, lithium tetraphenylborate, and imide.

The nonaqueous electrolyte may contain, for the purpose of improving charge / discharge characteristics, flame retardancy, etc., for example, pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, glyme, N, N-substituted imidazolidine, ethylene glycol dialkyl ether, ammonium salt, pyrrole, 2-methoxyethanol, aluminum trichloride and the like may be added have. 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.

In one specific _{example, LiPF 6, LiClO 4, LiBF} 4, LiN (SO 2 CF 3) 2 , such as a lithium salt, a highly dielectric solvent of DEC, DMC or EMC Fig solvent cyclic carbonate and a low viscosity of the EC or PC of And then adding it to a mixed solvent of linear carbonate to prepare a lithium salt-containing nonaqueous electrolyte.

The present invention provides a battery pack including such a stepped secondary battery, and further provides a device including such a battery pack as a power source.

The device may be, for example, a notebook computer, a netbook, a tablet PC, a mobile phone, MP3, a wearable electronic device, a power tool, an electric vehicle (EV), a hybrid electric vehicle (HEV) , A plug-in hybrid electric vehicle (PHEV), an electric bike (E-bike), an electric scooter (E-scooter), an electric golf cart, However, the present invention is not limited thereto.

The structure and manufacturing method of such a device are well known in the art, so a detailed description thereof will be omitted herein.

As described above, the method according to the present invention can manufacture electrode plates having different areas by using one unit electrode sheet, simplifying the manufacturing process and reducing manufacturing cost.

1 is a schematic view showing a process of manufacturing a unit electrode sheet using a general electrode sheet;
FIG. 2 is a schematic view showing a process of manufacturing an electrode plate by exciting a unit electrode sheet manufactured by slitting the electrode sheet of FIG. 1;
3 is a schematic view illustrating a process of manufacturing a unit electrode sheet using an electrode sheet according to an embodiment of the present invention;
FIG. 4 is a schematic view showing a process of manufacturing an electrode plate by notching a unit electrode sheet manufactured by slitting the electrode sheet of FIG. 3;
5 is a schematic view illustrating a process of manufacturing a unit electrode sheet using an electrode sheet according to another embodiment of 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.

FIG. 1 schematically shows a process of manufacturing a unit electrode sheet using a general electrode sheet.

1, the electrode sheet 100 includes five coating portions 111, 112, 113, 114, and 115 and five uncoated portions 121, 122, 123, and 124 on the current collector sheet 101 , 125).

The collector sheet 101 is longer than the transverse length and the collector sheet 101, the coating portions 111, 112, 113, 114 and 115 and the non-coated portions 121, 122, 123, The vertical length L1 is the same.

The coating unit 111, the non-coating unit 121, the coating unit 112, the non-coating unit 122, the coating unit 113, the non-coating unit 123, An uncoated portion 114, a coated portion 115, and a non-coated portion 125 are sequentially positioned.

The widths of the coating portions 111, 112, 113, 114 and 115 are equal to the width W1 and the widths of the non-coating portions 121, 122, 123, 124 and 125 are equal to the width W2.

When the electrode sheet 100 having such a structure is slit along the perforated lines A1, A2, A3, and A4 displayed on the right ends of the non-printed portions 121, 122, 123, and 124, And each unit electrode sheet includes one coating portion and one plain portion.

FIG. 2 schematically shows a process of manufacturing an electrode plate by notching a unit electrode sheet produced by slitting the electrode sheet of FIG. 1.

2, the unit electrode sheet 151 includes one coating portion 111 and a non-coated portion 121. The coated portion 111 is positioned on the left side and the non-coated portion 121 is positioned on the right side .

The uncoated portion 121 of the unit electrode sheet 151 was notched in the shape of the electrode tab 121a by using a notching mold to produce the electrode plate 151a. The electrode tab 121a is formed so as to extend from the current collector of the coating portion 111.

FIG. 3 schematically shows a process of manufacturing a unit electrode sheet using an electrode sheet according to an embodiment of the present invention.

Referring to FIG. 3, the electrode sheet 200 is constructed so that three unit electrode sheets can be manufactured by slitting the unit electrode sheet 251 as a basic unit, and the first coating portions 232, 233, 241, 242, which are relatively small in area, and second coating portions 221, 222, 223 and uncoated portions 231, 232, 233, 241, 242 which are relatively small in area.

The current collector sheet 201 is longer than the width and length of the current collector sheet 201 and the first and second coating portions 211, 212, 213, 221, 222, 223 and the non- 233, 241, and 242 have the same longitudinal length L1.

The first coating part 211, the non-coating part 231, the second coating part 221, the non-coating part 241, the first coating part 212, and the non-coating part 211 are formed on the current collector sheet 201 from left to right. The first coating part 232, the second coating part 222, the non-coating part 242, the first coating part 213, the non-coating part 233, and the second coating part 223.

The first coated portions 211, 212 and 213 have the same lateral length W1 and the second coated portions 221, 222 and 223 have the same lateral width W3. The uncoated portions 231, 232 and 233 The transverse lengths are the same as W2, and the widths of the plain portions 241 and 242 are equal to W4.

Three electrode unit sheets similar to the unit electrode sheet 251 can be produced by slitting the electrode sheet 200 along the perforated lines B1, B2, B3 and B4, and the plain sheets 241, Removed.

FIG. 4 schematically shows a process of manufacturing an electrode plate by notching a unit electrode sheet manufactured by slitting the electrode sheet of FIG. 3.

4, the unit electrode sheet 251 includes a first coating portion 211, a second coating portion 221, and a non-coating portion 231, and includes a first coating portion 211, The second coating portion 221 is located on the right side and the non-coated portion 231 is positioned between the first coating portion 211 and the second coating portion 221.

The uncoated portion 231 of the unit electrode sheet 251 is notched in the shape of the two electrode tabs 231a and 231b using the notched mold so that the electrode plate 251a having the size corresponding to the first coating portion 211 And an electrode plate 251b having a size corresponding to the second coating portion 221 were manufactured.

The electrode tab 231a is formed to extend from the current collector of the first coating portion 211 and the electrode tab 231b is formed to extend from the current collector of the second coating portion 221. [

4, only one type of electrode plate 151a can be manufactured by unifying one unit electrode sheet 151. Therefore, in order to manufacture two types of electrode plates having different areas, The manufacturing cost of the mold of the apparatus and the notching mold is doubled, the period for producing such a mold is longer, and the manufacturing cost of the unit current collector sheet is also increased. As a result, .

In contrast, since the unit electrode sheet 251 can produce two types of electrode plates 251a and 251b having different areas by notching, only one kind of the mold of the coating apparatus and the notching mold are required, It is possible to reduce the manufacturing period of the mold by half and to reduce the manufacturing cost of the mold by half compared to the conventional method and the manufacturing cost of the unit current collector sheet is also reduced by the step- But can be reduced to the manufacturing cost of a general-purpose secondary battery.

In addition, the unit electrode sheet 151 can manufacture only one electrode tab 121a from one uncoated portion 121. In contrast, the unit electrode sheet 251 can be manufactured from one uncoated portion 231, The tabs 231a and 231b can be manufactured, and the amount of the current collector sheets to be discarded after notching can be reduced.

5, a process of fabricating a unit electrode sheet using an electrode sheet according to another embodiment of the present invention is schematically shown.

Referring to FIG. 5 together with FIGS. 3 and 4, the electrode sheet 200a is formed by slitting so that three unit electrode sheets 251 as shown in FIG. 4 can be manufactured. (200).

The electrode sheet 200a includes the first coating portion 211, the second coating portion 223, the third coating portions 261 and 262 and the non-coated portions 231 and 232, Is longer than the width.

The first coated portion 211, the non-coated portion 231, the third coated portion 261, the non-coated portion 232, the third coated portion 262, and the uncoated portion 261 are formed on the collector sheet 201a from left to right. The second coating portion 233, and the second coating portion 223 in this order.

The first coating portion 211, the second coating portion 223 and the non-coating portions 231, 232 and 233 of the electrode sheet 200a are formed on the first coating portions 211, 212 and 213 of the electrode sheet 200, The second coating portions 221, 222, and 223 and the non-coated portions 231, 232, and 233.

The collector sheet 201a, the first, second and third coating portions 211, 223, 261 and 262 and the non-coated portions 231, 232 and 233 have the same longitudinal length L1. The first coated portion 211 has a width of W1, the second coated portion 223 has a width of W3, and the non-coated portions 231, 232, and 233 have the same width of W2. The third coating portions 261 and 262 have a width W5 that is a sum of the width W1 of the first coating portion 211 and the width W3 of the second coating portion 223.

When the electrode sheet 200a is slit along the perforated lines C1 and C2, three unit electrode sheets can be manufactured in the same manner as the unit electrode sheet 251 of FIG.

3, it is possible to simplify the slitting process because three unit electrode sheets 251 can be manufactured by two slits only when compared with the electrode sheet 200 of FIG. 3, 241 and 242 can be saved, so that the manufacturing cost can be reduced.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Claims (16)

A method of manufacturing an electrode plate for a secondary battery,
(a) fabricating a unit electrode sheet including a first coating portion, a second coating portion, and a non-coated uncoated portion on at least one side of a unit current collector sheet; And
(b) notching the non-coated portion in a shape of a first electrode tab and a second electrode tab;
Lt; / RTI &gt;
The uncoated portion is located between the first coating portion and the second coating portion, and the areas of the first coating portion and the second coating portion are different from each other,
The process (a) comprises the following (a1) to (a3):
(a1) preparing an electrode sheet by applying an electrode active material to a current collector sheet so that the structure of the unit electrode sheet including the first coating portion, the second coating portion and the non-coated portion is formed in at least two units, and drying the electrode active material;
(a2) rolling the electrode sheet; And
(a3) slitting the rolled electrode sheet in unit electrode sheet units. The method according to claim 1, wherein a unit electrode sheet including a first coating portion, a second coating portion, and a non-coated portion is formed on both sides of the unit current collector sheet in the step (a). The method according to claim 2, wherein the first coating portion, the second coating portion, and the non-coating portion are symmetrically located on both sides of the unit current collector sheet. The method of claim 1, wherein, in step (b), the first electrode tab is formed to extend from the current collector of the first coating part, and the second electrode tab is formed to extend from the second coating part . The method according to claim 1, wherein the first coating portion and the second coating portion have the same longitudinal lengths (L1) and different widths (W1, W3). delete 2. The method of claim 1, wherein in step (a1)
Wherein the electrode sheet has a length L1 equal to the first coating portion and the second coating portion and a length W1 of the combined length of the first coating portion's lateral length W1 and the second coated portion's lateral length W3 RTI ID = 0.0 &gt; W1 + W3. &Lt; / RTI &gt; The method according to claim 1, wherein in the step (a3), the third coating part is slitted to form a first coating part and a second coating part of different unit electrode sheets. A method for manufacturing an electrode sheet, comprising the steps of rolling and slitting an electrode sheet including a first coating portion, a second coating portion, and an uncoated non-coated portion in which an electrode active material is applied on at least one surface of a unit current collector sheet,
Wherein the uncoated portion is located between the first coating portion and the second coating portion, the areas of the first coating portion and the second coating portion are different from each other,
A unit electrode sheet capable of manufacturing two types of electrode plates having different areas by notching. 10. The plasma display panel of claim 9, wherein the non-coated portion is formed in a shape of a first electrode tab and a second electrode tab, the first electrode tab is formed to extend from a current collector of the first coated portion, And the tab is formed in a structure extending from the current collector of the second coating portion. delete delete delete delete delete delete

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