JP2007311280A - Manufacturing method of electrode plate for secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-quality and high-density electrode plate for a nonaqueous secondary battery by suppressing crease, disconnection and warpage of the electrode plate by pressing after removing an active material mix non-application region. <P>SOLUTION: In this manufacturing method of this electrode plate for a secondary battery, a positive electrode mix coating 2 is applied in a discontinued form in the longitudinal direction of a strip-like collector 1 and dried in a state where non-application regions 3 are left at both ends in the width direction of the strip-like collector 1, and then the electrode plate is pressed to a predetermined thickness with at least the non-application regions 3 at both ends in the width direction of the strip-like collector 1 removed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a secondary battery electrode plate having a high-density electrode active material layer in a non-aqueous secondary battery represented by a lithium ion battery.

In recent years, lithium secondary batteries, which are widely used as power sources for portable electronic devices, use a carbonaceous material capable of occluding and releasing lithium for the negative electrode, and a composite oxidation of lithium and a transition metal such as LiCoO _{2 for} the positive electrode. In this way, secondary batteries with high potential and high discharge capacity have been realized. However, with the recent increase in functionality of electronic devices and communication devices, higher capacities are desired. ing.

  Here, as an electrode plate for realizing a high-capacity battery, both a positive electrode plate and a negative electrode plate are coated with a mixture paint obtained by coating each constituent material on both sides of the current collector, and at least the width of the current collector In order to form an uncoated portion where no mixture paint is applied at both ends in the direction and increase the mixture density of the coated portion after drying, a method of compressing to a specified thickness by press working or the like is used. At this time, the mixture density is increased by filling with a larger amount of active material and pressing, thereby enabling a further increase in capacity.

However, in order to increase the active material density of the electrode plate, a larger pressure is required during press working, and wrinkles and cracks may occur at the boundary between the coated and uncoated parts of the mixture paint during press working. Furthermore, there is a problem that warping and cutting of the electrode plate occur.
Therefore, in order to reduce the distortion of the electrode plate such as undulations and wrinkles, as shown in FIG. 7, the electrode active material formed on the end portion in the width direction (Y-axis direction) of the positive electrode plate 31 is not coated. A method has been proposed in which a slit 33 parallel to the width direction of the current collector 32 is formed in the current collector 32 in the region 34 (see, for example, Patent Document 1).

  Further, in order to prevent the generation of wrinkles and cracks in the electrode plate, as shown in FIG. 8A, the positive electrode mixture or the negative electrode is applied to the current collector 41 with the uncoated portion 41a left on one side edge portion. In the electrode plate to which the mixture is applied, the region to be the uncoated portion 41a of the current collector 41 is formed in a state in which it is more easily stretched than the region to be the coated portion 42, or irregularities are formed or peeled from the uncoated portion 41a. After the tape is applied and applied, a method is proposed in which the application portion 42 is compression-molded by press rollers 43a and 43b as shown in FIG.

Further, in order to prevent the electrode plate from being cut or wrinkled, as shown in FIG. 9, when the electrode plate 53 in which the active material layer 54 is intermittently formed on the current collector 55 is pressed, The movable layer 58 is configured so that the outer tube 57 of the press roller 51 can be eccentric with respect to the shaft 59, and the upper press when pressing the portion where the active material layer 54 is formed as shown in FIG. The gap between the roller 51 and the lower press roller 52 is A1, and the upper press roller 51 and the lower press roller 52 are pressed when the portion where the active material layer 54 is not formed as shown in FIG. 9B. When the gap between the rollers is set to B1, the thickness of the current collector 55 is set to A1> B1 ≧ the current collector 55, whereby the upper press roller 51 is pressed when the current collector 55 portion where the active material layer 54 is not formed is pressed. And the lower press roller 52 are current collectors 55 How to configure so as not to contact it has been proposed (e.g., see Patent Document 3).
JP 2000-208129 A JP 2000-251942 A Japanese Patent Laid-Open No. 10-228897

  However, in the above-described prior art of Patent Document 1, since a long strip-shaped current collector is used, slitting both ends of the strip-shaped current collector over a long length deteriorates the strength of the electrode plate. The electrode plate meanders during processing, and the mixture is removed, making it difficult to perform slit processing.

  Moreover, in the prior art of patent document 2, it is necessary to pre-process both ends of a strip | belt-shaped electrical power collector by methods, such as annealing processing, uneven | corrugated formation, and tape sticking, etc., and it will take time and cost increase in pre-processing. .

  Furthermore, in the prior art of Patent Document 3, the effect of stress relaxation can be expected with respect to the uncoated portion formed by applying the belt-shaped current collector in the longitudinal direction intermittently, but the effect of stress relaxation can be expected. For the coated portion, such stress relaxation effect cannot be expected, and there is a problem that wrinkles and cracks, warping and cutting of the electrode plate occur.

  The present invention has been made in view of the above-described conventional problems, and the longitudinal direction of the current collector while leaving uncoated areas of the positive electrode mixture paint or the negative electrode mixture paint at both ends in the width direction of the belt-like current collector For secondary batteries that are pressed to a predetermined thickness with the uncoated areas removed at least at both ends in the width direction of the electrode plate that has been applied intermittently or applied to the entire surface and dried at least in the width direction. It aims at providing the manufacturing method of an electrode plate.

In order to achieve the above object, the method for producing an electrode plate for a non-aqueous secondary battery according to the present invention includes:
An active material comprising at least a lithium-containing composite oxide, a positive electrode mixture paint obtained by kneading and dispersing a conductive material and a water-insoluble polymer binder in a dispersion medium, or an active material comprising at least lithium and a non-active material A negative electrode mixture paint obtained by kneading and dispersing a water-soluble polymer binder with a dispersion medium is applied to a strip-like current collector intermittently or on the entire surface, and after drying, an active material layer is formed in the longitudinal direction of the current collector. A method of manufacturing an electrode plate for a secondary battery that presses and slits the formed electrode plate, while leaving an uncoated region of the positive electrode mixture paint or negative electrode mixture paint at both ends in the width direction of the current collector A positive or negative electrode mixture paint is applied intermittently or over the entire surface in the longitudinal direction of the current collector, and pressed to a predetermined thickness with at least uncoated areas at both ends in the width direction of the dried electrode plate removed. It is characterized by processing Than is.

  According to the method for producing an electrode plate for a secondary battery of the present invention, the method for producing the electrode plate for a non-aqueous secondary battery of the present invention includes a positive electrode mixture paint or a negative electrode compound at both ends in the width direction of the belt-like current collector. With the mixture paint applied intermittently or over the entire surface in the longitudinal direction of the current collector while leaving the uncoated area of the current collector, the uncoated areas at both ends in the width direction of the dried electrode plate are removed. When the active material mixture application area is pressed in the width direction of the electrode plate by pressing to a predetermined thickness, the stress applied to the current collector in this area and the unapplied area of the active material mixture are pressed. It is possible to apply a uniform pressure only to the active material mixture application region without causing a difference in stress from the stress applied to the current collector in this region (equal to almost none). Occurs during press processing of electrode plates applied to Wrinkles, cut, to suppress warpage or the like, it is possible to obtain a high-density electrode plate with high quality. Further, a high-capacity secondary battery can be realized by using this high-quality and high-density electrode plate.

In the first invention of the present invention, a positive electrode mixture paint obtained by kneading and dispersing at least an active material comprising a lithium-containing composite oxide, a conductive material and a water-insoluble polymer binder in a dispersion medium, or at least lithium. A negative electrode mixture paint obtained by kneading and dispersing an active material made of a material that can be held and a water-insoluble polymer binder in a dispersion medium is applied intermittently or over the entire surface of the belt-shaped current collector, and then collected after drying. A method for producing an electrode plate for a secondary battery in which an electrode plate having an active material layer formed in the longitudinal direction of the body is pressed and slit processed, and a positive electrode mixture paint or a negative electrode compound is formed on both ends of the current collector in the width direction. The positive electrode mixture paint or the negative electrode mixture paint is applied intermittently or over the entire surface in the longitudinal direction of the current collector while leaving the uncoated area of the agent paint, and at least the widthwise ends of the dried electrode plate are not applied. With the area removed, the When the active material mixture application area is pressed in the width direction of the electrode plate, the stress applied to the current collector in this area and the unapplied area of the active material mixture are pressed. There is no stress difference from the stress applied to the current collector in this area (equal to almost none), and uniform pressure can be applied only to the active material mixture application area. It is possible to suppress warping and the like.

  In the second aspect of the present invention, the positive electrode mixture paint or the negative electrode mixture paint is applied to the belt-like current collector, and the region including the sagging portion of the mixture paint at both ends in the width direction of the dried electrode plate Is applied to the current collector in the region when the region where the coating thickness of the active material mixture is constant is pressed in the width direction of the electrode plate, and the active material mixture When the sagging region where the coating thickness of the material is reduced is pressed, a uniform pressure can be applied only to the active material mixture coating region without causing a stress difference with the stress applied to the current collector in this region, It is possible to further enhance the effect of suppressing wrinkles, cutting, warping and the like that occur during pressing.

  In the third invention of the present invention, after pressing once with the uncoated area left at both ends in the width direction of the electrode plate, the uncoated area is removed and pressed to a predetermined thickness, Even when multiple pressing operations are performed, during the pressing process that is applied to the uncoated and coated areas of the active material mixture in the width direction of the electrode plate before the electrode plate is subjected to large stress due to the multiple pressing operations. Since the effect of suppressing wrinkles, cutting, warping, etc. that occur during press working can be obtained by relaxing the difference in stress state of the material, that is, relaxing between the differences in small stress state, the electrode plate is made more dense Is possible.

  In the fourth invention of the present invention, a press machine provided with a slitter was used to slit the uncoated areas at both ends of the electrode plate, thereby pressing the electrode plate to increase the density. It is possible to simplify the process of slitting to a specified width later.

  Below, an example of the manufacturing method of the electrode plate for secondary batteries in this invention is shown. First, the positive electrode active material, conductive material, and binder are placed in an appropriate dispersion medium, mixed and dispersed by a dispersing machine such as a planetary mixer, and adjusted to an optimum viscosity for application to a strip-shaped current collector. Kneading was performed to prepare a positive electrode mixture paint. Examples of active materials for positive electrode mixture paints include lithium cobaltate and modified products thereof (such as lithium cobaltate in which aluminum or magnesium is dissolved), lithium nickelate and modified products thereof (partially nickel is substituted with cobalt) And composite oxides such as lithium manganate and modified products thereof.

  As the conductive material at this time, for example, carbon black such as acetylene black, ketjen black, channel black, furnace black, lamp black and thermal black, and various graphites may be used alone or in combination.

  As the binder for the positive electrode mixture paint at this time, for example, polyvinylidene fluoride (PVdF), a modified polyvinylidene fluoride, polytetrafluoroethylene (PTFE), a rubber particle binder having an acrylate unit, or the like is used. In this case, an acrylate monomer or an acrylate oligomer into which a reactive functional group is introduced can be mixed in the binder.

  Next, the active material and binder for the negative electrode mixture paint are placed in an appropriate dispersion medium, mixed and dispersed by a dispersing machine such as a planetary mixer, and adjusted to the optimum viscosity for application to the current collector. Kneading was performed to prepare a negative electrode mixture paint. As an active material for the negative electrode mixture paint, various natural graphites, artificial graphite, silicon-based composite materials such as silicide, and various alloy composition materials can be used.

  Various binders such as PVDF and modified products thereof can be used as the binder for the negative electrode mixture paint at this time. From the viewpoint of improving lithium ion acceptability, styrene-butadiene copolymer rubber particles (SBR). In addition, it can be said that it is more preferable to use a cellulose resin such as carboxymethyl cellulose (CMC) in combination or a small amount thereof in the modified product.

  FIG. 1A is a plan view showing a state in which a mixture paint made of an active material of an electrode plate in one embodiment of the present invention is applied, and FIG. 1B is an active state of the electrode plate in the same embodiment. It is sectional drawing which shows the state which applied the mixture paint which consists of a substance. In the method for producing an electrode plate for a secondary battery of the present invention, as shown in FIG. 1A, the positive electrode plate or the negative electrode plate uses the positive electrode mixture paint and the negative electrode mixture paint produced as described above. The positive electrode mixture paint or the negative electrode mixture paint is intermittently applied and dried in the longitudinal direction of the belt-like current collector 1 with the uncoated regions 3 left at both ends in the width direction of the belt-like current collector 1. Thus, an electrode plate 4 in which an active material layer 2 was formed on a strip-shaped current collector 1 was produced.

  FIG. 2A is a plan view showing a state during pressing of the electrode plate in one embodiment of the present invention, and FIG. 2B is a cross-sectional view showing a state during pressing of the electrode plate in the same embodiment. It is. FIG. 4 is a cross-sectional view showing the pressing process of the electrode plate in one embodiment of the present invention. As shown in FIG. The uncoated region 3 of the active material mixture shown in FIG. 1A is removed by the installed slitter unit 13, and the active material layer 2 is formed at both ends in the width direction of the strip-shaped electrode plate 4 as shown in FIG. Then, the electrode plate 4 was pressed by passing the gap between the upper press roller 14 and the lower press roller 15 and winding the strip-shaped electrode plate 4 at the winding portion 16.

  Next, FIG. 5 is a cross-sectional view showing the press working of the electrode plate in another embodiment of the present invention. As shown in FIG. The gap between the roller 14 and the lower press roller 15 was passed, and the belt-like positive electrode plate 4 was wound up by the winding portion 16. Next, the winding portion 16 is reversed, and the belt-shaped electrode plate 4 is reversed and the feeding slitter 17 removes the uncoated region 3 of the active material mixture shown in FIG. As shown in FIG. 5, after the both end portions in the width direction of the belt-like electrode plate 4 are made of the active material layer 2 as shown in FIG. 2A, the gap between the upper press roller 14 and the lower press roller 15 is passed as shown in FIG. The belt-like positive electrode plate 4 was wound up by the reversed unwinding portion 12. Further, the belt-shaped electrode plate 4 is fed out from the unwinding portion 12 that has been normally rotated, passed through the gap between the upper press roller 14 and the lower press roller 15, and the belt-shaped electrode plate 4 is wound up by the winding portion 16. The electrode plate 4 was pressed.

  When the application region of the active material layer 2 is pressed in the width direction of the electrode plate 4 by the manufacturing method of the electrode plate 4, the stress applied to the current collector 1 in this region and the uncoated region 3 of the active material layer 2 Can be applied only to the application region of the active material layer 2 without causing a difference in stress from the stress applied to the current collector 1 in this region (which is almost equal to none). Wrinkles, cutting, warping, etc. that occur during processing can be suppressed.

FIG. 6 is a cross-sectional view showing the slit processing of the electrode plate in one embodiment of the present invention. As the slitter unit 13 shown in FIG. 4 and the slitter 17 shown in FIG. 5, for example, as shown in FIG. A gap between a pair of upper and lower shear blades 22 rotated by the rotary shaft 23 is constituted by a rotary shaft 23 having shear blades 22 installed at both ends of the spacer 21 set to a size necessary for removing the uncoated region 3. By passing the electrode plate 4 through, the uncoated region 3 can be removed. Further, embodiments of the present invention will be described with reference to the drawings.

  First, 100 parts by weight of lithium cobaltate as an active material, 2 parts by weight of acetylene black as a conductive agent with respect to 100 parts by weight of the active material, and 3 parts by weight of polyvinylidene fluoride as a binder with respect to 100 parts by weight of the active material Was mixed with an appropriate amount of N-methyl-2-pyrrolidone in a double-arm kneader to prepare a positive electrode mixture paint.

  Next, as shown in FIGS. 1A and 1B, this positive electrode mixture paint is applied with uncoated regions 3 at both ends in the width direction on the surface of the strip-shaped current collector 1 made of aluminum foil having a thickness of 15 μm. In the remaining state, the strip-shaped current collector 1 is applied and dried intermittently in the longitudinal direction, and then the back surface of the strip-shaped current collector 1 is also coated and dried in the same manner as the front surface. A belt-like positive electrode plate 4 having an active material layer 2 was prepared.

  Further, as shown in FIG. 4, the belt-like positive electrode plate 4 is fed out from the unwinding portion 12 and the slitter portion 13 (see FIG. 6 for details) is used to remove the uncoated region 3 in FIG. 2 (a) and (b), after the active material layer 2 is present at both ends in the width direction of the belt-like positive electrode plate 4, the gap between the upper press roller 14 and the lower press roller 15 is increased. The belt-shaped positive electrode plate 4 having a total thickness of 165 μm was produced by passing the film and winding the belt-shaped positive electrode plate 4 at the winding portion 16.

  The strip-shaped positive electrode plate 4 after pressing was slit to a width suitable for the size of the cylindrical secondary battery having a diameter of 18 mm and a height of 65 mm, thereby obtaining the positive electrode plate for a lithium ion battery of the present invention. In Example 1 above, as the positive electrode plate 4, as shown in FIG. 1A, the active material layer 2 applied intermittently in the longitudinal direction of the positive electrode plate 4 was used, but the present invention is limited to this. Instead, it is also possible to use a material in which the active material layer 2 is coated on the entire surface in the longitudinal direction of the positive electrode plate 4 as shown in FIGS. 3 (a) and 3 (b).

  The strip-like positive electrode plate 4 obtained in Example 1 was not cut during the pressing operation, and no abnormalities such as wrinkles were observed after pressing, and a high-density positive electrode plate 4 could be obtained. Further, the amount of warpage of the positive electrode plate 4 corresponding to both end rows of the positive electrode plate 4 slit to a width suitable for the size of the cylindrical secondary battery having a diameter of 18 mm and a height of 65 mm is measured. As a result, all were 0.5 mm / 1 m or less.

(Comparative Example 1)
On the other hand, as a comparison, the same positive electrode mixture paint as in Example 1 was used, and in the same manner as in Example 1, a belt-like positive electrode plate 4 having a single-sided mixture thickness of 100 μm after drying was produced. By pressing the belt-like positive electrode plate 4 with the uncoated region 3 shown in FIG. 1A left, the belt-like positive electrode plate 4 having a total thickness of 165 μm as shown in FIG. Produced. Further, slitting was performed in the same manner as in Example 1 to obtain a positive electrode plate 4 for a lithium ion battery of Comparative Example 1.

  The strip-like positive electrode plate 4 of Comparative Example 1 is wrinkled at the boundary between the uncoated region 3 and the coated region at both ends during the pressing operation, and when the wrinkle is large, the strip-shaped positive plate starts from this boundary. May occur. In addition, even when cutting does not occur, the positive electrode corresponding to both end rows of the positive electrode plate 4 in which the belt-like electrode plate 4 is slit to a width suitable for the size of the cylindrical secondary battery having a diameter of 18 mm and a height of 65 mm. When the amount of warping of the plate 4 was measured, it was greatly curved as 2 mm to 5 mm / 1 m.

  This is because, although a pressing pressure is applied to the strip-shaped current collector 1 immediately below the coating region via the active material layer 2, no pressing pressure is applied to the strip-shaped current collector 1 in the uncoated region 3. Tensile stress is generated in the longitudinal direction of the strip-shaped current collector 1 in the strip-shaped current collector 1 immediately below the region 3, and as a result, the boundary between the uncoated region 3 and the active material layer 2 that is the coated region is distorted. It is considered that the wrinkles of the strip-like positive electrode plate 4 and the warpage of the positive electrode plate 4 after cutting or slitting occur.

  First, 100 parts by weight of lithium cobaltate as an active material, 3 parts by weight of acetylene black as a conductive agent with respect to 100 parts by weight of active material, and 40 parts by weight of carboxymethyl cellulose as a thickener as a thickener (solid state of CMC) Appropriate amount of 10 parts by weight of an aqueous dispersion of fluororesin copolymer (solid content 40% by weight) as a binder (4 parts by weight in terms of solid content of binder) A positive electrode mixture paint was prepared by stirring and kneading with a double-arm kneader together with water.

  Next, as shown in FIG. 1 (a), in the state where the uncoated regions 3 are left at both ends in the width direction on the surface of the strip-shaped current collector 1 made of 15 μm thick aluminum foil, The belt-shaped current collector 1 is intermittently applied and dried in the longitudinal direction, and then the back surface of the band-shaped current collector 1 is coated and dried in the same manner as the front surface, and the active material layer 2 having a single-sided thickness of 105 μm after drying. A positive electrode plate 4 was prepared.

  Further, as shown in FIG. 5, the belt-like positive electrode plate 4 is sent out from the unwinding portion 12 and passed through the gap between the upper press roller 14 and the lower press roller 15, and the belt-like positive electrode plate 4 is wound at the winding portion 16. I took it. Next, the winding portion 16 is reversed, the belt-like positive electrode plate 4 is sent out from the winding portion 16, and the uncoated region 3 in FIG. 1A is removed by a slitter 17 (see FIG. 6 for details). As shown in (a), after making the both ends of the width direction in the strip | belt-shaped positive electrode plate 4 into the state which consists of the active material layer 2, it passes through the clearance gap between the upper press roller 14 and the lower press roller 15, and the unwinding part 12 Then, the belt-like positive electrode plate 4 was wound up. Further, the belt-like positive electrode plate 4 is fed out from the unwinding portion 12, passed through the gap between the upper press roller 14 and the lower press roller 15, and the belt-shaped positive plate 4 is wound up by the winding portion 16, so that the total thickness becomes 155 μm. A belt-like positive electrode plate 4 was prepared.

  The strip-shaped positive electrode plate after pressing was slit to a width suitable for the size of the cylindrical secondary battery having a diameter of 18 mm and a height of 65 mm, thereby obtaining a positive electrode plate for a lithium ion battery of the present invention. In Example 2 described above, as the positive electrode plate 4, as shown in FIG. 1A, the active material layer 2 applied intermittently in the longitudinal direction of the positive electrode plate 4 was used. However, the present invention is not limited to this. Alternatively, as shown in FIG. 3A, it is possible to use a material in which the active material layer 2 is coated on the entire surface in the longitudinal direction of the positive electrode plate 4.

  The strip-like positive electrode plate 4 obtained in Example 2 was not cut during the pressing operation, and no abnormalities such as wrinkles were observed after pressing, and a high-density positive electrode plate could be obtained. In addition, the amount of warpage of the positive electrode plate 4 corresponding to both end rows of the positive electrode plate 4 slit to a width suitable for the size of the cylindrical secondary battery having a diameter of 18 mm and a height of 65 mm was measured. , Both were 0.5 mm / 1 m or less.

(Comparative Example 2)
On the other hand, as a comparison, the same positive electrode mixture paint as in Example 2 was used, and in the same manner as in Example 2, a belt-like positive electrode plate 4 having a single-sided mixture thickness of 105 μm after drying was produced. The belt-like positive electrode plate 4 having a total thickness of 155 μm was produced by pressing the belt-like positive electrode plate 4 while leaving the uncoated region 3 shown in FIG. Further, slitting was performed in the same manner as in Example 2 to obtain a positive electrode plate 4 for a lithium ion battery of Comparative Example 2.

  Although the belt-like positive electrode plate 4 of Comparative Example 2 did not have a particularly large problem at the time of the first press, it was at the boundary between the uncoated area 3 and the coated area at both ends during the second or third press operation. When wrinkles are generated and the wrinkles are large, the strip-shaped positive electrode plate 4 may be cut from this boundary. In addition, even when cutting does not occur, the positive electrode plate corresponding to both end rows of the positive electrode plate 4 slit to the width suitable for the size of the cylindrical secondary battery having a diameter of 18 mm and a height of 65 mm. When the amount of warpage of No. 4 was measured, it was greatly curved as 3 mm to 7 mm / 1 m.

  This is because, although a pressing pressure is applied to the strip-shaped current collector 1 immediately below the coating region via the active material layer 2, no pressing pressure is applied to the strip-shaped current collector 1 in the uncoated region 3. Is increased, the tensile stress generated in the longitudinal direction of the strip-shaped current collector 1 gradually increases in the strip-shaped current collector 1 immediately below the uncoated region 3. As a result, the uncoated region 3 It is considered that the strain concentrates on the boundary between the active material layer 2 that is the coating region and the positive electrode plate 4 is wrinkled, cut or warped after the slit. As described above, the best mode for carrying out the present invention has been described. In the above embodiment, the embodiment of the positive electrode plate has been described. However, the present invention is not limited to this, and similarly has a high density. It can also be applied when producing a negative electrode plate.

  Further, in the above-described embodiment, the embodiment in which only the uncoated area of the active material mixture on the belt-like current collector is shown, but the present invention is not limited to this, and the application of the active material mixture From the viewpoint of applying a uniform press pressure to the region, it is possible to remove the uncoated region, including the sagging portion of the active material mixture at both ends in the width direction that occurs when the band-shaped current collector is applied and dried. More preferred. From the above results, by using the present invention, wrinkling and cutting of the strip electrode plate and warping of the electrode plate can be suppressed, and a high quality and high density electrode plate for a secondary battery can be obtained.

  The electrode plate for a non-aqueous secondary battery according to the present invention is a positive electrode mixture paint or a negative electrode mixture in the longitudinal direction of the strip current collector in a state where uncoated areas are left at both ends in the width direction of the strip current collector. By applying and drying the paint intermittently, and then pressing to a predetermined thickness in a state where at least the uncoated areas at both ends in the width direction of the belt-like current collector are removed, a high-quality and high-density electrode plate can be obtained. It is useful as a battery for a portable power source and the like for which higher capacity is desired along with the multifunctionalization of electronic devices and communication devices.

(A) The top view which shows the state which apply | coated the mixture coating consisting of the active material of the electrode plate which concerns on one embodiment of this invention, (b) The mixture coating consisting of the active material of the electrode plate which concerns on the embodiment Sectional view showing the state of applying (A) The top view which shows the state at the time of the press of the electrode plate which concerns on one embodiment of this invention, (b) Sectional drawing which shows the state at the time of the press of the electrode plate which concerns on the state of the embodiment (A) The top view of the electrode plate which concerns on another embodiment of this invention, (b) Sectional drawing of the electrode plate which concerns on the embodiment Sectional drawing which shows the press work of the electrode plate which concerns on one embodiment of this invention Sectional drawing which shows the press work of the electrode plate which concerns on another embodiment of this invention Sectional drawing which shows the slit process of the electrode plate which concerns on one embodiment of this invention Conventional electrode plate (A) A plan view showing a conventional electrode plate, (b) a sectional view showing a pressed state of the conventional example (A) Cross-sectional view showing the pressed state of the electrode plate of the conventional example, (b) Cross-sectional view showing another pressed state in the conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Current collector 2 Active material layer 3 Non-application | coating area | region 4 Electrode plate 12 Unwinding part 13 Slitter part 14 Upper press roller 15 Lower press roller 16 Winding part 17 Slitter 21 Spacer 22 Share blade 23 Rotating shaft

Claims (4)

  An active material comprising at least a lithium-containing composite oxide, a positive electrode mixture paint obtained by kneading and dispersing a conductive material and a water-insoluble polymer binder in a dispersion medium, or an active material comprising at least lithium and a non-active material A negative electrode mixture paint obtained by kneading and dispersing a water-soluble polymer binder with a dispersion medium is applied to a strip-like current collector intermittently or on the entire surface, and after drying, an active material layer is formed in the longitudinal direction of the current collector. A method of manufacturing an electrode plate for a secondary battery that presses and slits the formed electrode plate, wherein the positive electrode mixture paint or the negative electrode mixture paint is not applied to both ends of the current collector in the width direction. The positive electrode mixture paint or the negative electrode mixture paint was applied intermittently or over the entire surface in the longitudinal direction of the current collector, leaving at least uncoated areas at both ends in the width direction of the dried electrode plate Press to a predetermined thickness in the state Method for producing a nonaqueous secondary battery electrode plate, characterized by Engineering.   A positive electrode mixture paint or a negative electrode mixture paint is applied to a strip-shaped current collector, and after removing the region including the sagging portion of the mixture paint at both ends in the width direction of the dried electrode plate, it is pressed to a predetermined thickness. The manufacturing method of the electrode plate for non-aqueous secondary batteries of Claim 1 characterized by the above-mentioned.   The non-coated region is removed and pressed to a predetermined thickness after pressing is performed once with the uncoated region left at both ends in the width direction of the electrode plate. A method for producing an electrode plate for an aqueous secondary battery. The method for producing an electrode plate for a non-aqueous secondary battery according to claim 1, wherein uncoated areas at both ends of the electrode plate are slit using a press machine equipped with a slitter.

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