JP2012004059A - Battery electrode plate manufacturing method and manufacturing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a battery electrode plate without producing an excess electrode material portion which lowers the safety of an electrode plate and without disposing of the excess portion.SOLUTION: A removal mechanism 20 comprises a bobbin holder 26 for holding a thread 25, a tensile force control mechanism 28 for controlling the tensile force of the thread 25, an intermediate holder 27, and a recovery unit 29 for recovering a removed excess portion in the width direction, 3a. The thread 25 of the removal mechanism 20 abuts on the side of a collector 2 at an angle of less than 90 degrees with respect to the plane of the collector 2, and its component force in the horizontal direction of compressive force toward the inside is set to a value greater than 0.1 [kgf] but not large enough to cause wrinkles or breakage in an electrode plate 21 depending on a material of the collector. The excess portion in the width direction, 3a, is thereby peeled off and then recovered by the recovery unit 29 for reuse. The excess portion in the width direction, 3a, of an electrode plate 1 is removed and recovered through the removal mechanism 20, whereby an electrode plate 21 is obtained.

Description

  The present invention relates to a battery electrode plate manufacturing method and a manufacturing apparatus.

  In recent years, lithium secondary batteries are used for power storage facilities, high-function terminals, and the like, and therefore, higher capacities are desired. For this purpose, it is an object to provide a battery electrode plate having a uniform thickness so as to hold a large amount of active material in a limited volume and not to leave a space.

  As a conventional battery electrode plate manufacturing method, the electrode material 3 is formed into a sheet by a pair of rolls 4 and 5 shown in FIG. 4 and then transferred to the traveling current collector 2 by the roll 6 to manufacture the electrode plate 1. A method to do this has been proposed (Patent Document 1).

  The manufactured electrode plate 1 is rolled to an appropriate density and then cut into a width used in an actual battery by using a slitter to obtain a plurality of hoops (band-like plates). In general, cutting by a slitter shown in FIG. 5 is used, and an electrode plate drawn out from the wide electrode plate 7 after rolling is cut into a slit 8 through some guide rolls and wound around a winding portion. Thus, narrow electrode plates 9a and 9b are formed (see, for example, Patent Document 2).

  At this time, only the hoops satisfying a predetermined weight, thickness, and width are used as the positive and negative plates of the battery, and those that do not satisfy the requirements are discarded.

Japanese Patent No. 2869156 Japanese Patent No. 2008-176939

  However, in the conventional manufacturing method as shown in FIG. 4, the electrode material 3 is applied to the end of the current collector width by using the current collector 2 without loss in order to reduce material loss. Therefore, the width of the sheet-like electrode material 3 formed by a roll needs to be slightly wider than the width of the traveling current collector 2. As shown in FIG. 6, the finished electrode plate 1 is in a state in which the electrode material 3 protrudes to a portion where the current collector 2 is not in the center in the cross section in the width direction.

  Since the protruding part of the electrode material 3 is fragile, the subsequent negative electrode plate / positive electrode plate / separator is wound to form a battery, so that the material is likely to fall off and scatter, causing a short circuit failure. Therefore, the electrode plate 1 after transfer having a shape as shown in FIG. 7 in the cross section in the width direction is cut by a slitting process and divided into a waste end portion 10 and a narrow electrode plate portion 11, and the narrow electrode plate The part 11 is sent to the assembly process, and the waste end part 10 is discarded.

  The present invention solves the above-mentioned problems of the prior art, and can be manufactured without producing an excessive electrode material portion that can cause a significant decrease in safety on the electrode plate and without discarding the waste end portion. It aims at providing the manufacturing method of a battery electrode plate which can be performed.

  In order to achieve the above object, a method for manufacturing a battery electrode plate according to the present invention includes an electrode on one or both surfaces of a current collector plane that travels from an unwinding portion to a winding portion. A method of manufacturing a battery electrode plate to which a material is attached, comprising a thread abutting on both sides of a current collector on both sides in the width direction, and an angle formed between the current collector plane and the thread is 15 degrees or more and less than 90 degrees A certain removing mechanism is provided in the running path of the current collector, and an excess portion of the electrode material adhering in the electrode plate width direction on the side surface of the current collector is removed by the removing mechanism.

  Moreover, the horizontal component force which compresses the collector side surface with which the thread | yarn of a removal mechanism contact | abuts inward from the both ends of the width direction is larger than 0.1 [kgf], and it is an electrode plate according to the material of a collector. Set to a value that does not cause wrinkles or tears, remove the excess part of the electrode material, and recover the removed electrode material by means of collecting the excess part of the electrode material removed from the electrode plate provided in the removal mechanism And re-use.

  The battery electrode plate manufacturing apparatus is a battery electrode plate manufacturing apparatus in which an electrode material is attached to one or both of the front and / or back of the current collector plane running from the unwinding unit to the winding unit. , Reusing the yarn that is in contact with the side surface of the current collector from both ends in the width direction and the angle between the current collector plane and the current collector plane is 15 degrees or more and less than 90 degrees and the electrode material in the electrode plate width direction Therefore, it has a means for recovering an excess portion of the electrode material removed by the yarn, and is provided with a removal mechanism provided in the running path of the current collector.

  According to the above apparatus and method, in the electrode plate in which the electrode material is adhered to the traveling current collector plane, the excess portion of the electrode material at both ends in the width direction of the electrode plate is removed by the removing mechanism, and the excess portion is removed. Battery electrode plates can be manufactured by recovery and reuse.

  According to the present invention, an excess electrode material portion that can cause a significant reduction in safety is generated on the electrode plate in a state where the electrode material adheres to either or both of the front surface and the back surface of the current collector. There is an effect that it is possible to manufacture a battery electrode plate without any of them.

The schematic block diagram which shows the manufacturing method of the battery electrode plate in embodiment of this invention. The enlarged view which shows the outline of the removal mechanism in this embodiment In the present embodiment, (a) is the force applied to the battery electrode plate of the yarn used in the removal mechanism, (b) is the range of the electrode plate to be good, (c) is the electrode material to be removed from the extreme end of the current collector Figure explaining Schematic configuration diagram showing a conventional method for producing a battery electrode plate by roll transfer Schematic configuration diagram showing a conventional method for manufacturing a battery electrode plate with slits A perspective view showing an electrode plate in which the electrode material is wider than the current collector The figure explaining the electrode plate processing in which the electrode material is wider than the current collector

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing a method for manufacturing a battery electrode plate in an embodiment of the present invention. Here, components having functions corresponding to the constituent members described with reference to FIG.

  As shown in FIG. 1, the current collector 2 attached to the unwinding 22 is held by a roll 16 in the first application section, and the electrode material 3 is transferred to one surface between the roll 14 and dried. Pass the furnace 17 through. Further, the electrode plate 3 is transferred to the other surface between the rolls 14 in the second application section and passed through the drying furnace 19, and then the electrode plate 1 is obtained. The electrode plate 1 is converted into an electrode plate 21 through a removing mechanism 20 and then wound up by a winding device 23.

  The rolls 13b and 14 are arranged in parallel so as to form a predetermined gap between their outer peripheries, and have a function of adjusting the thickness of the electrode material 3 discharged from the extrusion die 13a and passing through the gap. Yes.

  The peeling roll 15 is a means for providing an intermittent portion having a predetermined length and interval in the coating film of the electrode material 3, and may perform a function of removing a part of the coating film even if the shape changes. A part of the peeling roll 15 has a convex shape, and the peeling roll 15 is arranged in parallel so as to form a predetermined gap between the convex part, the roll 14, and the outer periphery of each other. Remove.

  Moreover, the roll 16 is arrange | positioned in parallel so that a predetermined | prescribed gap may be formed between the outer periphery of the roll 14, and the thickness was adjusted to the collector 2 which drive | works the roll 14 and the roll 16 on one direction. It has a function of transferring the electrode material 3.

  The width of the film-like electrode material 3 formed by the rolls 13b and 14 is, for example, in order to prevent a portion without the electrode material 3 from occurring in the width direction of the current collector 2 due to meandering of the current collector 2. When the meandering control range during travel of the current collector 2 is 1 [mm], it is desirable that the current collector 2 is set wider by 1 [mm] or more than the width of the current collector 2.

  On the surfaces of the rolls 13b and 14, a resin containing a material having high releasability typified by silicon and fluorine and a composite metal object impregnated and containing these components (for example, nickel plating containing fluorine) are included. Can be used.

  In addition, as a roll, a SUS roll is regularly grooved or blasted and coated with a highly releasable material represented by silicon or fluorine, and a circumferential surface is provided so that a smooth surface can be obtained. Removability typified by silicon or fluorine is caused by material that has been processed and the surface coated with a material having high releasability regularly or randomly on a partial surface, or small cracks that occur when chrome plating is applied. After a high material is melted and applied, a material in which the surface is polished and a surface on which a material having a high releasability is randomly applied is partially exposed can be used.

  The material of the peeling roll 15 can be SUS polished, chrome plated, or nickel plated. For example, the roll 16 may be SUS polished, chrome plated, or nickel plated.

  The drying furnace 17 and the drying furnace 19 have a function of removing moisture from the coating film, and hot air, far infrared, middle infrared, electromagnetic induction heating, or the like can be used as a method.

  In addition, the same roll as each roll of a 1st application part is used for each roll of a 2nd application part, and the function is also the same. However, as for the peeling roll 15, when the length of the intermittent portion is different between the front and back of the electrode plate, the length of the convex portion changes accordingly.

  The removal mechanism 20 has a function of removing the electrode material 3 excessively attached in the width direction of the current collector 2 by the transfer operation described above.

  The take-up 23 has a function of taking up the manufactured electrode plate 21.

  FIG. 2 is an enlarged view showing an outline of the removal mechanism of the present embodiment. The removal mechanism 20 of FIG. 2 includes a thread 25, a thread winding holder 26 that can hold the thread 25 at an angle with respect to the electrode plate 1 (21), a tension control mechanism 28 that controls the tension of the thread 25, It comprises an intermediate holder 27 that holds the thread 25 between the electrode plate 1 (21) and the tension control mechanism 28, and a recovery device 29 that recovers the excess 3a in the width direction of the removed electrode material.

  The electrode plate 1 that has passed through the drying furnace 19 can be passed through the removing mechanism 20 to form the electrode plate 21 from which the excess 3a in the width direction of the electrode material 3 of the electrode plate 1 has been removed and collected. The removal mechanism 20 has a thread winding holder 26 above the electrode plate 1 (21), and a thread 25 hung from the thread winding holder 26 extends downward. The thread 25 is in contact with the end in the width direction of the electrode plate 21, The tension is controlled by the tension adjusting mechanism 28 via the intermediate holder 27. It can be used when the material of the thread 25 of the removal mechanism 20 is a natural fiber such as hemp, cotton, wool, or silk, or an artificial fiber such as nylon or polyester.

  The width direction surplus 3a of the electrode plate 1 peeled off by the thread 25 is recovered by the recovery device 29, and the recovered width direction surplus 3a is weighed and charged when the electrode material 3 is blended again. Will be reused. Thereby, a material utilization rate improves markedly. As a system of the recovery device 29, a vacuum system such as a vacuum cleaner, an electrostatic system, a system in which a solution component is adsorbed to powder by a vapor and dropped can be used.

  The transfer of the electrode material 3 in the method for manufacturing the battery electrode plate of this embodiment shown in FIG. 1 was tested as follows.

  In a state where the roll 13b and the roll 14 of the first application unit are rotated, a certain amount of the electrode material 3 is supplied to the surface of the transfer source roll 13b. And it adjusts so that it may become predetermined thickness with the gap between the roll 13b and the roll 14, and also peels the film-form electrode material 3 on the roll 14 intermittently using the roll 14 and the peeling roll 15 To do. After the film-like electrode material 3 is transferred onto the current collector 2 running on the roll 16, this is passed through a drying furnace 17, and the surface of the electrode plate 1 is produced. Thereafter, the back surface of the electrode plate 1 is produced in the second application part by the same method as that for the front surface.

  In the first and second application portions, the diameter of the roll 13b is 300 [mm], the width is 300 [mm], the diameter of the roll 14 is 300 [mm], the width is 300 [mm], and the diameter of the peeling roll 15 is 300 [mm], the width was 300 [mm], the diameter of the roll 16 was 300 [mm], and the width was 300 [mm]. Further, the peeling roll 15 was provided with one convex portion having a width of 300 [mm], a circumferential length of 10 [mm], and a height of 1 [mm] on the outer peripheral portion of the roll. The coating width was determined by the width of the discharge port slit of the extrusion die 13a and was set to 122 [mm].

  The number of rotations of the rolls 13 b, 14, 15, and 16 in the first application unit was set to a number corresponding to 20 [m / min] in accordance with the traveling speed of the current collector 2. The gap between the roll 13b and the roll 14 is 150 [μm], the gap between the roll 14 and the convex portion of the peeling roll 15 is 150 [μm], and the gap between the roll 14 and the roll 16 is (180 [μm]. μm] = 150 [μm] + the thickness of the current collector 2 30 [μm]). The roll 13b and roll 14 were each baked with silicon on the surface, and the peeling roll 15 and roll 16 were chrome-plated.

  Also in the second application part, the gap between the roll 13b and the roll 14 is 150 [μm], the gap between the roll 14 and the convex part of the peeling roll 15 is 150 [μm], and the roll 14 and the roll The gap between them was set to 150 [μm] + the surface thickness of the electrode plate (120 [μm]). The roll 13b and roll 14 were each baked with silicon on the surface, and the peeling roll 15 and roll 16 were chrome-plated.

  The electrode material 3 has, as a first composition, lithium nickelate (hereinafter referred to as LiNiO2) as an active material, acetylene black as a conductive agent, and polyvinylidene fluoride (as a first binder of a water-insoluble polymer). Hereinafter referred to as PVDF) and n-methyl-2-pyrrolidone (hereinafter referred to as NMP) as a non-aqueous dispersion solvent, and a second composition as an active material. Graphite, sodium carboxymethylcellulose (hereinafter referred to as CMC) as a first binder of a water-soluble polymer, styrene butadiene rubber (hereinafter referred to as SBR) as a second binder, and pure water as a solvent The electrode material of the water-based negative electrode formed by mixing is shown in the following (Table 1). Moreover, the supply amount from the extrusion die at each location was 293 [cc / min].

  In the case of the positive electrode, a solid content concentration of 76 to 86 [wt%] was transferable, and in the case of the negative electrode, a solid content concentration of 66 to 76 [wt%] was transferable. In the present embodiment, the positive electrode plate was manufactured with a solid content concentration of 86 [wt%] by blending the first composition, and the negative electrode plate was manufactured with a solid content concentration of 76 [wt%] by blending the second composition.

3A shows the force applied to the battery electrode plate of the yarn used in the removal mechanism in this embodiment, FIG. 3B shows the range of the electrode plate to be good, and FIG. 3C shows the end of the current collector. It is a figure explaining the electrode material to remove. The horizontal component force 33 of the yarn 25 is equal to or less than the shear fracture stress of the current collector 2 and a load that does not cause buckling of the current collector 2 can be used.
(Equation 1)
H = F × cos θ
Here, H: horizontal component force 33, F: tension 31 of thread 25, θ: angle 32 between pole plate 1 and thread 25
As shown in

  In addition, the tension | tensile_strength to the electrical power collector 2 concerning a running direction in order for the winding 23 to wind up is determined by the allowable tensile stress, the width | variety, and thickness of the electrical power collector 2 to be used. In other words, the current collector 2 is determined by the material and shape of the material, and if it is pulled with a tension exceeding the allowable range, the current collector 2 may be torn, so that it cannot be used beyond the allowable range.

  For this reason, in the embodiment using the removing mechanism 20, the winding tension of the electrode plate 21 taken up by the winding 23 is set in the range of 0.5 to 8.0 [kgf], and the horizontal component force generated by the yarn 25 is used. 33 was changed within the range of 0.1 to 1.5 [kgf], and the state of the electrode plate 21 was confirmed.

  Table 2 shows the results when the wire 25 used had a wire diameter of 1.5 [mm], the material was cotton, and the negative electrode plate (electrode material of the second composition) was removed. The current collector 2 was a copper foil having a width of 120 [mm] and a thickness of 30 [μm].

  In (Table 2), after removing the excess 3a in the width direction of the electrode plate 1 with the yarn 25 of the removing mechanism, the current collector 2 is exposed by 0.01 [mm] or more. Or the excess electrode material 3 is 0.02 [mm] or less (see FIG. 3B).

  In addition, the electrode plate 21 in which the winding deviation has occurred is in a state in which a position deviation of the wound electrode plate 21 has occurred by 1 [mm] or more in the winding 23. If there is a winding deviation, a defect occurs when winding in the assembly process.

  The generation of wrinkles in the electrode plate is a state in which the electrode plate 21 is broken because a force (a horizontal component 33 of the yarn 25) between the electrode plate 21 and the yarn 25 is strong in the width direction of the electrode plate 21.

  The occurrence of indentation into the electrode plate means that in the width direction of the electrode plate 21, the force with which the electrode plate 21 is sandwiched between the threads 25 (the horizontal component 33 of the thread 25) is too strong. This is a state where the electrode plate 21 is indented.

  Yarn breakage is a state in which the tension of the yarn 25 exceeds the breaking stress of the yarn 25 and is torn.

  The occurrence of electrode plate breakage is a state in which the tension of the electrode plate 21 exceeds the breaking stress of the electrode plate 21 and tears.

  In addition, when the angle 32 between the electrode plate 21 and the thread 25 is θ = 90 ° or more, there is a portion that cannot be partially removed. On the other hand, by setting θ to less than 90 °, it was possible to remove all the surplus electrode material 3.

  Specifically, the portion of the electrode plate 21 removed from the endmost portion of the current collector 2 in the electrode material 3 having a thickness of 120 [μm] (see FIG. 3C) is the electrode plate 21 (current collector). 2) When the angle 32 between the thread 25 is θ = 10 °, the removal rate of the electrode material 3 is 0.73 [%], and when θ = 15 ° is 0.48 [%], The ratio in the case of θ = 30 ° is 0.2 [%]. Since the capacity reduction of the removed electrode material 3 is 0.5% or less, from the viewpoint of this capacity, the range of the angle 32 formed by the electrode plate 21 (current collector 2) and the thread 25 is θ = 15 ° or more and less than 90 °.

  Furthermore, the wire 25 used has a wire diameter of 0.75 [mm], the material is cotton, and the results when the negative electrode plate (electrode material of the second composition) is removed are shown in (Table 3). The current collector 2 was a copper foil having a width of 120 [mm] and a thickness of 30 [μm].

  The wire 25 used has a wire diameter of 3.0 [mm], the material is cotton, and the results when the negative electrode plate (electrode material of the second composition) is removed are shown in (Table 4). The current collector 2 was a copper foil having a width of 120 [mm] and a thickness of 30 [μm].

  From the results of (Table 2) to (Table 4) described above, the lower limit is 0.6 [kgf] and the upper limit is the range of winding tension in which a copper foil having a width of 120 [mm] and a thickness of 30 [μm] can travel suitably. It was 7.9 [kgf], and it was found that the range was suitable for use.

  In addition, the lower limit of the horizontal component force 33 that can suitably remove excess electrode material 3 is 0.1 [kgf] regardless of the wire diameter of the yarn 25.

  The upper limit of the horizontal component force 33 is proportional to the diameter of the yarn 25 when the wire diameter of the yarn 25 is 1.5 [mm] or less. On the other hand, when the wire diameter of the thread | yarn 25 exceeded 1.5 [mm], it turned out from the experimental result that the upper limit of the horizontal direction component 33 is 0.8 [kgf].

  There are two failure modes when the upper limit of the horizontal component force 33 is exceeded, and one is when the wire diameter of the yarn 25 is 1.5 [mm] or less, and the yarn 25 sinks into the electrode plate 21. This seems to be because the shear force generated by the horizontal component force 33 generated by the yarn 25 reached the shear fracture stress of the copper foil. Secondly, when the wire diameter of the yarn 25 exceeds 1.5 [mm], electrode plate wrinkles occur. This is presumably because the electrode plate 21 reached the limit stress due to the horizontal component force 33 of the yarn 25 and buckled.

  Next, a result when only the thickness of the current collector 2 is halved without changing other conditions is shown. Here, the wire diameter of the used thread 25 is 1.5 [mm], the material is cotton, and the results when the negative electrode plate (electrode material of the second composition) is removed are shown in (Table 5). The current collector 2 was a copper foil having a width of 120 [mm] and a thickness of 15 [μm].

  Furthermore, Table 6 shows the results when the wire diameter of the used yarn was 3.0 [mm], the material was cotton, and the negative electrode plate (electrode material of the second composition) was removed. A copper foil having a width of 120 [mm] and a thickness of 15 [μm] was used as the current collector.

  Table 7 summarizes the above results.

  (Table 7) shows that the upper limit of the winding tension changes in proportion to the thickness of the copper foil used as the current collector 2, and there is a proportional relationship between the thickness and the upper limit of the winding tension. It was. On the other hand, the lower limit of the winding tension may be 0.6 [kgf] or more regardless of the thickness of the current collector 2.

  Further, the lower limit of the horizontal component force 33 that can suitably remove the excess electrode material 3 is 0.1 [kgf] or more regardless of the wire diameter of the yarn 25. What is the thickness of the copper foil? There is no relationship.

  On the other hand, when the thickness of the copper foil is doubled, the upper limit of the horizontal component force 33 is doubled. For example, when the wire 25 has a wire diameter of 1.5 [mm] and the current collector 2 has a thickness of 15 [μm], the upper limit of the horizontal component force 33 is 0.4 [kgf]. The upper limit of the winding tension is 4.0 [kgf].

  When the wire 25 has the same wire diameter of 1.5 [mm] and the thickness of the current collector 2 is 30 [μm], which is twice the previous thickness, the upper limit of the horizontal component force 33 is 0.8 [ kgf], and the upper limit of the winding tension is almost doubled to 7.9 [kgf].

  This is because the shearing force generated by the yarn 25 is inversely proportional to the area of the side surface of the copper foil with which the yarn 25 is in contact, and the area is reduced by the reduction in the thickness of the copper foil. It seems to reach to. In addition, even in the case of buckling, it seems that, as the shear fracture stress, when the thickness is reduced, the critical stress is reached with a small force, leading to buckling.

  Although the results are omitted, only the thickness of the electrode material 3 is changed, the thickness of the current collector 2 is 30 [μm], the wire diameter of the used thread 25 is 1.5 [mm], the material is cotton, and the negative electrode plate ( When the electrode material of the second composition was removed, the results were exactly the same as in (Table 2). That is, the thickness of the electrode material 3 does not affect the winding tension and the horizontal component force 33.

  Next, as a positive electrode plate in the same manner as the negative electrode plate, the current collector 2 was replaced with an aluminum foil having a thickness of 30 [μm] and a width of 120 [mm], and the results of the same examination as described above were obtained (Table 8) to ( Table 10) shows.

  The wire 25 used has a wire diameter of 0.75 [mm], the material is cotton, and the results when the positive electrode plate (electrode material of the first composition) is removed are shown in (Table 8). The current collector 2 was an aluminum foil having a thickness of 30 [μm] and a width of 120 [mm].

  Further, the yarn 25 used has a wire diameter of 1.5 [mm], a material of cotton, and the result when the positive electrode plate (electrode material of the first composition) is removed is shown in (Table 9). The current collector 2 was an aluminum foil having a thickness of 30 [μm] and a width of 120 [mm].

  The wire 25 used has a wire diameter of 3.0 [mm], a material of cotton, and the results when the positive electrode plate (electrode material of the first composition) is removed are shown in (Table 10). The current collector 2 was an aluminum foil having a thickness of 30 [μm] and a width of 120 [mm].

  Table 11 summarizes the above results.

  As a result of investigating the material of the current collector 2 by changing to aluminum foil, a result similar to that of the copper foil was obtained. The upper limit of the winding tension that can be suitably run is about 3/4 that of the copper foil. Both of the upper limits of the horizontal component force 33 that can suitably remove the electrode material 3 were about ½ of that of the copper foil. The lower limit of the winding tension was 0.6 [kgf], and the lower limit of the horizontal component force 33 was 0.1 [kgf].

  The result of changing the thickness with the positive electrode plate is omitted, but when the thickness is halved, the upper limit of the take-up tension that can travel suitably similarly to the copper foil, the horizontal component force 33 that can suitably remove the electrode material 3 Both upper limits were halved.

  In the positive electrode plate, the lower limit of the range of the horizontal component force 33 of the yarn 25 that can be suitably removed is 0.1 [kgf] or more.

As in this embodiment, the electrode material 3 is
(1) a non-aqueous positive electrode material obtained by kneading and dispersing an active material comprising a lithium-containing composite oxide, a conductive material, and a water-insoluble polymer binder in a non-aqueous dispersion solvent;
(2) A water-based positive electrode material in which an active material comprising a lithium-containing composite oxide, a conductive material, and a water-soluble polymer binder are kneaded and dispersed in an aqueous dispersion solvent,
(3) A negative electrode material obtained by kneading and dispersing an active material capable of holding at least lithium and a water-soluble polymer binder in an aqueous dispersion solvent,
Can be suitably used.

  Next, in order to compare the effects, using one of the examples as an example, the electrode plate 21 from which the excess 3a in the width direction of the electrode material 3 of the electrode plate 1 is removed is manufactured using the removal mechanism 20 of the present embodiment, and the other is used. As a comparative example, an electrode plate was manufactured by the same method as the conventional manufacturing method described in Patent Documents 1 and 2. In addition, each material used for the comparative example used the completely same thing as an Example.

  Then, using these electrode plates, evaluation was performed based on the number of short-circuit defects and the material utilization rate when 1000 batteries were used.

  In the examples and comparative examples, the positive electrode plate was manufactured with a solid content concentration of 86 [wt%] by blending the first composition, and the negative electrode plate was manufactured with a solid content concentration of 76 [wt%] by blending the second composition.

The material utilization rate is
(Equation 2)
Material utilization rate [%] = (Materials and parts used as electrode plates) ÷ (All input materials and parts) x 100
It is represented by

  The results are shown in (Table 12).

  In the comparative example, a small amount of short circuit failure due to metal burrs at the time of slitting occurred, and the material utilization rate was worse than that of the example.

  The method and apparatus for manufacturing a battery electrode plate according to the present invention may cause a significant reduction in safety on the electrode plate in which an electrode material is attached to either or both of the front surface and the back surface of the current collector. It is possible to obtain a battery electrode plate that does not generate excessive electrode material, and is useful for the production of battery electrode plates such as non-aqueous or aqueous secondary batteries and lithium batteries. The present invention can also be applied to a method for manufacturing an electric double layer capacitor, a display dielectric layer, etc. formed by mixing with a solvent or the like.

DESCRIPTION OF SYMBOLS 1, 21 Electrode plate 2 Current collector 3 Electrode material 3a Surplus in width direction 4, 5, 6 Roll 7 Wide electrode plate 8 Slit 9a, 9b Narrow electrode plate 10 Disposal end 11 Narrow electrode plate 13a Extrusion die 13b , 14, 16 Roll 15 Peeling roll 17, 19 Drying furnace 20 Removal mechanism 22 Unwinding 23 Winding 25 Thread 26 Thread winding holder 27 Intermediate holder 28 Tension control mechanism 29 Recovery device 31 Tension 32 Angle 33 Horizontal component force

Claims (4)

A method for producing a battery electrode plate in which an electrode material is adhered to one or both of the front and / or back of a current collector plane running from an unwinding part to a winding part,
A removal mechanism that includes a thread that contacts the current collector side surface from both side ends in the width direction, and an angle formed by the current collector plane and the thread is 15 degrees or more and less than 90 degrees. A method for manufacturing a battery electrode plate, comprising: removing an excess portion of the electrode material attached in the electrode plate width direction on the side surface of the current collector by the removing mechanism.   The electrode plate according to the material of the current collector has a horizontal component force greater than 0.1 [kgf] for compressing the current collector side surface with which the yarn of the removing mechanism abuts from both side ends in the width direction. 2. The method for manufacturing a battery electrode plate according to claim 1, wherein a surplus portion of the electrode material is removed by setting to a value that does not cause wrinkles or tears.   The battery electrode plate according to claim 1 or 2, wherein the removed electrode material is collected and reused by means for collecting an excess portion of the electrode material removed from the electrode plate provided in the removing mechanism. Method. In the battery electrode plate manufacturing apparatus in which the electrode material is attached to either the front or the back of the current collector plane running from the unwinding unit to the winding unit or both surfaces,
The yarn that is in contact with the side surface of the current collector from both side ends in the width direction and that forms an angle of 15 degrees or more and less than 90 degrees with the current collector plane, and the excess portion of the electrode material in the electrode plate width direction are re-reused. A battery electrode plate comprising: a removing mechanism provided in a traveling path of the current collector; and means for recovering an excess portion of the electrode material removed by the thread. Manufacturing equipment.

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