JP2006318672A - Manufacturing methods of electrode and battery, and manufacturing device of electrode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an electrode, a manufacturing method of a battery, and a manufacturing device of an electrode with reliability improved by preventing a protruded object such as an active material from penetrating a separator to cause physical short circuiting. <P>SOLUTION: An electrode layer 120 provided at a collector 110 is pressurized by a first roll 221. After that, an exposed area 100B where the collector layer 110 is exposed without the electrode layer 120 formed is pressurized by a second roll 231 with a smaller diameter than the first roll 221 at a pressure of 10 N/cm or more and 20 N/cm or less. The protruded object like the active material adhered to a non-pressurized area not pressurized by the first roll 221 is crushed without fail and a height of the protruded object is lowered. A slanted part with a tapered slope is desired to be put at either end in a width direction of the second roll 221. Pure water as an example as cooling liquid is desired to be sealed inside the second roll 221. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrode manufacturing method in which an electrode layer containing an active material is formed on a part of a current collector, a battery manufacturing method using the method, and an electrode manufacturing apparatus used in the method.

  In recent years, many portable electronic devices such as a camera-integrated VTR (video tape recorder), a mobile phone, or a notebook computer have appeared, and their size and weight have been reduced. Batteries used as portable power sources for these electronic devices, particularly secondary batteries, are actively used as key devices for research and development aimed at improving energy density. Among them, non-aqueous electrolyte secondary batteries (for example, lithium ion secondary batteries) can provide a larger energy density than conventional lead batteries and nickel cadmium batteries, which are conventional aqueous electrolyte secondary batteries. Considerations are being made in various directions.

In a lithium ion secondary battery, a pair of electrodes in which an electrode layer containing an active material is formed on a current collector are stacked or wound with a separator in between to form an electrode body, and the electrode body is enclosed in a can or the like There are various shapes such as a cylindrical shape and a square shape. In the manufacturing process of such a lithium ion secondary battery, if the thickness of the electrode body is too large, it may become defective when inserted into a can or the like. Therefore, conventionally, after forming the electrode layer on a part of the current collector, the electrode layer is heated and pressurized by a press facility, and the electrode layer is compressed to reduce the thickness of the electrode (for example, (See Patent Document 1.)
JP-A-5-129020

  However, in the conventional press facility, as shown in FIG. 12, since a large roll 431 having a diameter of 500 mm or more is used, a portion about several mm from the step 300C at the end of the electrode layer 320 on the current collector 310 is used. Was not pressurized and was in an unpressurized region 300D. As a result, the height of protrusions such as active materials attached to the non-pressurized region 300D remains unreduced, and when the electrode body is constructed, the protrusions penetrate the separator and cause a physical short circuit. There was a problem of doing.

  The present invention has been made in view of such problems, and the object thereof is to prevent protrusions such as an active material from penetrating the separator and causing a physical short circuit, thereby improving reliability. An electrode manufacturing method, a battery manufacturing method, and an electrode manufacturing apparatus used in the method are provided.

  An electrode manufacturing method according to the present invention is for manufacturing an electrode in which an electrode layer containing an active material is formed on a part of a current collector, and the electrode layer provided on the current collector is pressurized by a first roll. After pressing the electrode layer with the first roll after the step, the region of the current collector that is exposed without the electrode layer being formed is 10 N / cm by the second roll having a smaller diameter than the first roll. And a step of pressurizing at a pressure of 20 N / cm or less.

  A method of manufacturing a battery according to the present invention is a method of manufacturing a battery in which a pair of electrodes in which an electrode layer containing an active material is formed on a part of a current collector is disposed with a separator interposed therebetween. After pressing at least one of the electrode layers provided on the current collector with the first roll, a region of the current collector that is exposed without the electrode layer being formed has a diameter smaller than that of the first roll. It is formed by pressurizing with a second roll having a pressure of 10 N / cm or more and 20 N / cm or less.

  An electrode manufacturing apparatus according to the present invention manufactures an electrode in which an electrode layer containing an active material is formed on a part of a current collector, and the electrode layer provided on the current collector is added by a first roll. The first pressurizing part to be pressed and the electrode pressed by the first pressurizing part, the region of the current collector that is exposed without forming the electrode layer is a second having a diameter smaller than that of the first roll. And a second pressurizing unit that pressurizes with a roll at a pressure of 10 N / cm or more and 20 N / cm or less.

  In the electrode manufacturing method of the present invention, after the electrode layer provided on the current collector is pressed by the first roll, the region of the current collector that is exposed without being formed is the first layer. The second roll having a smaller diameter than the roll is pressurized at a pressure of 10 N / cm or more and 20 N / cm or less.

  In the battery manufacturing method of the present invention, after at least one of the pair of electrodes is manufactured by the electrode manufacturing method of the present invention, the pair of electrodes are arranged with a separator in between.

  In the electrode manufacturing apparatus of the present invention, after the electrode layer provided on the current collector is pressed by the first roll in the first pressurizing unit, the second pressurizing unit applies the first pressurizing unit. About the pressed electrode, the area | region exposed without forming an electrode layer among electrical power collectors is pressurized by the pressure of 10 N / cm or more and 20 N / cm or less with the 2nd roll which has a diameter smaller than a 1st roll. Is done.

  According to the method for manufacturing the electrode of the present invention, the method for manufacturing the battery of the present invention, or the apparatus for manufacturing the battery of the present invention, the electrode layer provided on the current collector is pressurized by the first roll, and then the current collector In the first roll, the region exposed without forming the electrode layer is pressed with a pressure of 10 N / cm or more and 20 N / cm or less by a second roll having a smaller diameter than the first roll. Therefore, it is possible to reliably crush the protrusions such as the active material attached to the area that has not been pressurized, thereby reducing the height of the protrusions. Therefore, it is possible to prevent the protrusions from penetrating the separator and form a physical short when the electrode body is configured, thereby improving the reliability.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the figure, each component schematically shows the shape, size, and arrangement relationship to the extent that the present invention can be understood, and is different from the actual size.

  FIG. 1 shows a cross-sectional structure of a secondary battery manufactured by an electrode manufacturing apparatus according to an embodiment of the present invention. The secondary battery 10 is a so-called cylindrical type, and has an electrode body 20 inside a battery can 11 having a substantially hollow cylindrical shape. The battery can 11 is made of, for example, iron (Fe) plated with nickel (Ni), and has one end closed and the other end open. Inside the battery can 11, a pair of insulating plates 12 and 13 are arranged perpendicular to the winding peripheral surface so as to sandwich the electrode body 20.

  At the open end of the battery can 11, a battery lid 14, a safety valve mechanism 15 provided inside the battery lid 14 and a heat sensitive resistance element (Positive Temperature Coefficient; PTC element) 16 are interposed via a gasket 17. It is attached by caulking, and the inside of the battery can 11 is sealed. The battery lid 14 is made of, for example, the same material as the battery can 11. The safety valve mechanism 15 is electrically connected to the battery lid 14 via the heat sensitive resistance element 16, and the disk plate 15A is reversed when the internal pressure of the battery exceeds a certain level due to an internal short circuit or external heating. Thus, the electrical connection between the battery lid 14 and the electrode body 20 is cut off. When the temperature rises, the heat sensitive resistance element 16 limits the current by increasing the resistance value and prevents abnormal heat generation due to a large current. The gasket 17 is made of, for example, an insulating material, and asphalt is applied to the surface.

  The electrode body 20 is formed by laminating and winding a positive electrode 21 and a negative electrode 22 with a separator 23 interposed therebetween, and a center pin 24 made of stainless steel or the like is inserted in the center. The positive electrode 21 is a positive electrode current collector made of, for example, an aluminum foil, and an electrode layer containing a positive electrode active material such as a lithium-containing compound, and the negative electrode 22 is made of, for example, a negative electrode current collector made of copper foil or the like. The body is provided with an electrode layer containing a negative electrode active material such as a carbon material capable of inserting and extracting lithium. The separator 23 is made of, for example, a porous film such as polypropylene, and the separator is impregnated with an electrolytic solution in which an electrolyte salt such as a lithium salt is dissolved in a non-aqueous solvent such as carbonate. Yes. A positive electrode lead 25 made of aluminum (Al) or the like is connected to the positive electrode 21 of the electrode body 20, and a negative electrode lead 26 made of nickel or the like is connected to the negative electrode 22. The positive electrode lead 25 is electrically connected to the battery lid 14 by being welded to the safety valve mechanism 15, and the negative electrode lead 26 is welded to and electrically connected to the battery can 11.

  FIG. 2 shows the overall configuration of an electrode manufacturing apparatus used for manufacturing the secondary battery 10 shown in FIG. This electrode manufacturing apparatus is for performing pressure treatment on the positive electrode 21 and the negative electrode 22, and includes, for example, an unwinding section 210, a first pressure section 220, a second pressure section 230, and a winding section. It is divided into 240 four-stage routes. In addition, you may provide a guide roll, a support member, etc. which are not shown in these each part.

  As shown in FIG. 3, the positive electrode 21 and the negative electrode 22 are obtained by intermittently forming the electrode layer 120 on a part of the current collector 110. That is, a plurality of electrode regions 100A in which the electrode layer 120 is formed is provided on the current collector 110, and the region between the plurality of electrode regions 100A is not formed with the electrode layer 120 and is collected. It is an exposed region 100B where the body 110 is exposed. On the boundary line between the electrode region 100A and the exposed region 100B, a step 100C having a height of about 200 μm, for example, is generated. Further, a protrusion 130 such as an active material is attached to the exposed region 100B.

  The unwinding section 210 is a path for unwinding the current collector 110 provided with the electrode layer 120 from the unwinding roll 211.

  The first pressure unit 220 is a path for pressing the electrode layer 120 provided on the current collector 110 with the first roll 221. For example, two first rolls 221 are arranged one above the other so that the current collector 110 provided with the electrode layer 120 can be sandwiched therebetween.

  Note that the first pressurizing unit 220 may selectively pressurize only the electrode layer 120 by controlling the pressure of the first roll 221, or the entire current collector 110 provided with the electrode layer 120. You may make it pressurize.

  The first roll 221 is made of, for example, metal. The diameter of the first roll 221 is preferably 500 mm or more, for example. This is because the electrode layer 120 and the first roll 221 can be brought into surface contact, and damage to the electrode layer 120 and the current collector 110 can be reduced. In addition, since the pressure of up to 1 t is applied to the first roll 221, the strength of the first roll 221 can be ensured by setting the diameter of the first roll 221 to 500 mm or more.

  The pressure by the first roll 221 is preferably set to 3 kN / cm or more and 6.4 kN / cm or less, for example. This is because if it is smaller than 3 kN / cm, the electrode layer 120 cannot be sufficiently pressurized, and if it is larger than 6.4 kN / cm, the current collector 110 may be broken.

  The second pressurizing unit 230 causes the exposed region 100 </ b> B of the electrode pressurized by the first pressurizing unit 210 to be 10 N / cm or more and 20 N / cm or less by the second roll 231 having a smaller diameter than the first roll 221. Pressurize with pressure. Thereby, in this electrode manufacturing apparatus, the protrusion 130 such as the active material attached to the area that is not pressed by the first roll 221 in the exposed area 100B is reliably crushed, and the height of the protrusion 130 is increased. It can be reduced.

  The second roll 231 is made of, for example, hard chrome (Cr) plated metal. Specifically, the diameter of the second roll 231 is preferably, for example, 100 mm or less, but is desirably large enough to ensure strength. On the other hand, if it is larger than 100 mm, the area not pressed by the first roll 221 cannot be pressed by the second roll 231.

  As shown in FIG. 4, the second roll 231 is disposed so as to overlap the fixed roll 232, and the cylinder 233 is connected to both ends via a connecting member 233 </ b> A. The second roll 231 is driven by the air pressure of the cylinder 233. An electrode is sandwiched between 231 and the fixed roll 232 so that pressure can be applied. The pressure by the second roll 231 is 10 N / cm or more and 20 N / cm or less as described above. This is because if it is less than 10 N / cm, the height of the protrusion 130 cannot be sufficiently reduced, and if it is greater than 20 N / cm, the pressing effect is reduced by bending of the second roll 231.

  Note that the second pressurizing unit 230 may selectively pressurize only the exposed region 100B by controlling the pressure of the second roll 221 by the cylinder 233, or the current collector 110 provided with the electrode layer 120. You may make it pressurize the whole.

  FIG. 5 illustrates a cross-sectional configuration of the second roll 231 in the width direction. It is preferable that the 2nd roll 231 has the inclination part 231A which gave the taper inclination to the width direction both ends. This is because even when the second roll 231 is bent, the second roll 231 can be uniformly pressed in the width direction, and the current collector 110 can be prevented from being wrinkled. The amount of inclination t of the inclined portion 231A is preferably 20 μm or more and 30 μm or less, for example. This is because a higher effect can be obtained.

  In addition, it is preferable that the cooling liquid 234 is sealed inside the second roll 231. Since the first pressurizing unit 220 pressurizes the electrode while applying heat, the second roll 231 absorbs the heat of the electrode and the temperature rises. At the end in the width direction of the second roll 231, radiant heat is emitted from the end surface, so the temperature is low, and temperature unevenness occurs at the center and the end in the width direction. As a result, a difference appears in the thermal expansion amount between the center portion in the width direction and the end portion, and the thermal expansion amount in the center portion in the width direction becomes larger than the end portion (thermal expansion amount: center portion> end portion). The pressure may not be transmitted uniformly in the width direction. However, by sealing the coolant 234 inside the second roll 231, it is possible to eliminate temperature unevenness between the central portion and the end portion in the width direction of the second roll 231. Therefore, the amount of thermal expansion of the second roll 231 can be made uniform in the width direction, and the protrusions 130 such as the active material adhering to the area not pressurized by the first roll 221 can be crushed uniformly.

  As the cooling liquid 234, for example, pure water is preferable. This is because pure water does not contain impurities, so the quality can be maintained for a long period of time and it can be handled without maintenance. Moreover, it is because it can prevent effectively that rust generate | occur | produces in the 2nd roll 231 inside.

  The fixed roll 232 shown in FIGS. 2 and 4 is made of resin, for example. As with the second roll 231, the fixed roll 232 preferably has a cooling liquid 234 such as pure water sealed therein.

  The winding unit 240 illustrated in FIG. 2 is a path for winding the electrode pressurized by the second pressure unit 230 around the winding roll 241.

  FIG. 6 shows the flow of an electrode manufacturing method using such an electrode manufacturing apparatus, and FIG. 7 shows the process. First, in order to form the positive electrode 21, the electrode layer 120 is formed on a part of the current collector 110. Next, the current collector 110 provided with the electrode layer 120 is placed on the unwinding section 210 and unwound from the unwinding roll 211, and the electrode layer 120 is pressurized by the first roll 221 in the first pressurizing section 220 ( Step S101). At this time, as shown in FIG. 7A, when the height of the step 100C is 200 μm and the diameter of the first roll 221 is 500 mm, a portion of the exposed region 100B that is about 4 mm from the step 100C is the first roll 221. No pressure is applied, and the unpressurized region 100D is obtained.

  Subsequently, the exposed region 100B of the electrode pressurized by the first pressure unit 220 is pressurized by the second pressure unit 240 at a pressure of 10 N / cm or more and 20 N / cm or less by the second roll 231 (step S102). . As a result, as shown in FIG. 7B, the protrusion 130 such as the active material attached to the unpressurized region 100D that has not been pressurized by the first roll 221 in the exposed region 100B is reliably crushed. Thus, the height of the protrusion 130 is reduced.

  After that, the electrode pressurized by the second pressure unit 230 is wound around the winding roll 241 in the winding unit 240. Thus, the positive electrode 21 is formed. The negative electrode 22 is formed in the same manner as the positive electrode 21.

  After forming the positive electrode 21 and the negative electrode 22, the positive electrode lead 25 is attached to the current collector 110 of the positive electrode 21 by welding or the like, and the negative electrode lead 26 is attached to the current collector 110 of the negative electrode 22 by welding or the like. Subsequently, the positive electrode 21 and the negative electrode 22 are laminated and wound with the separator 23 interposed therebetween, and then cut at an appropriate position to produce the electrode body 20.

  After producing the electrode body 20, the electrode body 20 is sandwiched between the pair of insulating plates 12 and 13, the negative electrode lead 26 is welded to the battery can 11, and the positive electrode lead 25 is welded to the safety valve mechanism 15. The battery can 11 is accommodated in the battery can 11, and the electrolytic solution is injected into the battery can 11 and impregnated in the separator 23. After that, the battery lid 14, the safety valve mechanism 15, and the heat sensitive resistance element 16 are fixed to the opening end of the battery can 11 by caulking the gasket 17 therebetween. Thereby, the secondary battery 10 shown in FIG. 1 is completed.

  As described above, in the present embodiment, after the electrode layer 120 provided on the current collector 110 is pressurized by the first roll 221, the exposed region 100 </ b> B is changed to the second roll 231 having a smaller diameter than the first roll 221. Since the pressure is applied at a pressure of 10 N / cm or more and 20 N / cm or less, the protrusions such as the active material attached to the unpressurized region 100D that is not pressurized by the first roll 221 in the exposed region 100B. 130 can be crushed reliably and the height of the protrusion 130 can be reduced. Therefore, when the electrode body 20 is configured, it is possible to prevent the protrusion 130 from penetrating the separator 23 and cause a physical short circuit, thereby improving the reliability.

  In particular, since the tapered portions 231A are provided at both ends in the width direction of the second roll 231, even when bending of the second roll 231 occurs, the second roll 231 is uniform in the width direction. Can be pressurized. Therefore, the local pressure applied by the bending of the second roll 231 can be eliminated, and the current collector 110 can be prevented from being wrinkled.

  In addition, since the coolant 234 is sealed inside the second roll 231, temperature unevenness between the center portion and the end portion in the width direction of the second roll 231 can be eliminated. Therefore, the amount of thermal expansion of the second roll 231 is made uniform in the width direction, and the protrusion 130 such as an active material attached to the non-pressurized region 100D that has not been pressurized by the first roll 221 can be uniformly crushed. it can.

  Further, specific embodiments of the present invention will be described in detail.

Example 1
The positive electrode 21 described in the above embodiment was manufactured. An electrode layer 120 containing lithium / cobalt composite oxide (LiCoO ₂ ) as a positive electrode active material was formed on a part of a current collector 110 made of an aluminum foil having a thickness of 20 μm.

  After the electrode layer 120 was formed on a part of the current collector 110, pressure treatment was performed using the electrode manufacturing apparatus shown in FIG. At that time, after the electrode layer 120 was pressurized by the first roll 221 having a diameter of 500 mm, a pressure of 20 N / cm was applied to the exposed region 100B by the second roll 231 having a diameter of 100 mm. In addition, pure water was sealed in the second roll 231 as the cooling liquid 234.

  As Comparative Example 1 with respect to Example 1, the second roll is made of resin, and except that no pressure is applied by the second roll by not providing a cylinder (0 N / cm). In the same manner as in Example 1, a positive electrode was formed.

  Moreover, as Comparative Example 2 with respect to Example 1, a positive electrode was formed in the same manner as in Example 1 except that the pressure applied by the second roll was 25 N / cm.

(Example 2)
A positive electrode 21 was formed in the same manner as in Example 1 except that inclined portions 231A were provided at both ends in the width direction of the second roll 231 and the inclined amount t of the inclined portion 231A was 20 μm.

(Example 3)
The positive electrode 21 was formed in the same manner as in Example 2 except that the cooling liquid 234 was not sealed in the second roll 231.

  With respect to the positive electrodes of Examples 1 and 2 and Comparative Examples 1 and 2 thus obtained, the height of the protrusions in the exposed region and the presence or absence of wrinkles on the current collector were examined. The obtained results are shown in Table 1.

  In addition, about the wrinkle of an electrical power collector, it was set as (circle) when wrinkles generate | occur | produced, and when it did not occur. Regarding the height judgment of the protrusions, ○ is satisfied when all of the average value is 10 μm or less, the maximum value is less than 19 μm, and the standard deviation σ is 4.5 or less, and when one or two are satisfied, Δ is not satisfied. When it was, it was set as x.

  In addition, for Example 2 and Comparative Example 1, the relationship between the height of the protrusion from the exposed region boundary line and its height was examined. The results are shown in FIGS. 8 and 9, respectively.

  Furthermore, for Examples 2 and 3, the relationship between the number of continuous treatments and the change in surface temperature in the width direction of the second roll 231 was examined. The results are shown in FIG. 10 and FIG. In addition, it was 74 degreeC when the temperature of the electrode layer 120 in the entrance of the 2nd roll 231 was measured.

  As can be seen from Table 1, in Example 1, the height of the protrusions was higher than in Comparative Example 1 in which no pressure was applied by the second roll and in Comparative Example 2 in which the pressure applied by the second roll was 25 N / cm. Was reduced. On the other hand, in Comparative Examples 1 and 2, the maximum heights of the protrusions were 37 μm and 22 μm, respectively, exceeding the separator thickness of 20 μm.

  That is, if the electrode layer 120 is pressed by the first roll 221 and then the exposed region 100B is pressed by the second roll 231 at a pressure of 20 N / cm or less, the first roll 221 in the exposed region 100B is applied. It was found that the protrusions such as the active material adhering to the unpressurized region 100D that was not pressed can be reliably crushed and the height of the protrusions can be reduced.

  Comparing Example 1 and Example 2, in Example 2 in which the second roll 231 is provided with the inclined portion 231A, the average value of the height of the protrusion is higher than that in Example 1 in which the inclined portion 231A is not provided. , The maximum value and the standard deviation σ were both improved, and the current collector 110 was not wrinkled. That is, if the second roll 231 is provided with the inclined portion 231A, even when the second roll 231 is bent, the second roll 231 can be uniformly pressed in the width direction, and the current collector 110 can be pressed. It was found that wrinkles can be prevented from occurring.

  As can be seen from FIGS. 8 and 9, in Example 2, there was no protrusion exceeding 20 μm in height in the exposed region 100 </ b> B. On the other hand, in Comparative Example 1, protrusions having a height of more than 20 μm are concentrated in a region within 4 mm from the boundary line between the electrode region 100A and the exposed region 100B, and this region is the first roll. It was an unpressurized area 100D that was not pressurized by.

  Furthermore, as can be seen from FIGS. 10 and 11, in Example 2 in which the cooling liquid 234 was sealed inside the second roll 231, there was no temperature unevenness between the central portion and the end portion in the width direction. On the other hand, in Example 3 in which the cooling liquid 234 was not sealed, the temperature difference between the central portion and the end in the width direction increased with the increase in the number of continuous treatments, and the temperature unevenness of 13.9 ° C. with 600 continuous treatments. Has occurred. That is, it has been found that if the cooling liquid 234 is sealed inside the second roll 231, temperature unevenness between the center portion and the end portion in the width direction of the second roll 231 can be eliminated.

(Examples 4 to 9)
A positive electrode 21 was formed in the same manner as in Example 1 except that the pressure applied by the second roll 231 and the inclination amount t of the inclined portion 231A were changed as shown in Table 2. The ninth embodiment is the same as the second embodiment.

  Thus, about the positive electrode 21 of Examples 4-9 obtained, the height of the protrusion in the exposure area | region 100B and the presence or absence of the wrinkle of the electrical power collector 110 were investigated. The obtained results are shown in Table 2 together with the results of Comparative Example 1.

  As can be seen from Table 2, in Examples 4 to 9, the height of the protrusions was reduced as compared with Comparative Example 1 in which no pressure was applied by the second roll. That is, if the electrode layer 120 is pressed by the first roll 221 and then the exposed region 100B is pressed by the second roll 231 at a pressure of 10 N / cm or more and 20 N / cm or less, the pressure is applied by the first roll 221. It was found that the protrusions such as the active material attached to the unpressurized region 100D that were not made can be reliably crushed and the height of the protrusions can be reduced.

  Further, when Examples 4 and 5 are compared with Examples 6 to 9, in Examples 6 to 9 in which the inclination amount t of the inclined portion 231A is 20 μm or more and 30 μm or less, the current collector 110 was not wrinkled. In contrast, in Examples 4 and 5 in which the thickness was less than 20 μm, the current collector 110 was wrinkled. That is, it was found that the wrinkles of the current collector 110 can be suppressed by setting the amount of inclination t of the inclined portion 231A to 20 μm or more and 30 μm or less.

  As the negative electrode 22, an electrode layer 120 containing a carbon material as a negative electrode active material was formed on a part of a current collector 110 made of a copper foil having a thickness of 15 μm, and pressure treatment was performed in the same manner as in the above example. However, the same results as in the above example were obtained.

  Although the present invention has been described with reference to the embodiments and examples, the present invention is not limited to the above embodiments and examples, and various modifications can be made. For example, in the above-described embodiments and examples, the case where both the positive electrode 21 and the negative electrode 22 are manufactured by the electrode manufacturing method of the present invention and the battery manufacturing apparatus of the present invention has been described. You may make it manufacture at least one of 22 with the manufacturing method of the electrode of this invention, and the manufacturing apparatus of the battery of this invention.

  Further, for example, in the above-described embodiments and examples, the configuration of the electrode manufacturing apparatus has been specifically described, but the configuration of the electrode manufacturing apparatus is not limited to the above-described embodiments and examples. For example, a feeding part for adjusting the tension of the electrode may be provided between the unwinding part 210 and the first pressure part 220.

  Furthermore, for example, in the above-described embodiments and examples, the case where the electrode body 20 has a structure in which the positive electrode 21 and the negative electrode 22 are stacked and wound is described. However, the electrode body 20 is formed by folding the positive electrode 21 and the negative electrode 22. It may be rolled up or stacked.

  In addition, for example, in the above embodiments and examples, the cylindrical secondary battery has been described, but the present invention can also be applied to secondary batteries of other shapes.

  Furthermore, for example, in the above-described embodiments and examples, the case where the secondary battery 10 is manufactured by the battery manufacturing apparatus of the present invention has been described. However, the present invention is not necessarily limited thereto. It is also possible to manufacture a primary battery having a similar structure.

  In addition, for example, in the above-described embodiments and examples, the case where an electrolytic solution that is a liquid electrolyte is used as a solvent has been described. However, another electrolyte may be used instead of the electrolytic solution. Other electrolytes include, for example, a gel electrolyte in which an electrolyte is held in a polymer compound, a solid electrolyte having ionic conductivity, a mixture of a solid electrolyte and an electrolyte, or a solid electrolyte and a gel electrolyte. And a mixture thereof.

  Note that various polymer compounds can be used for the gel electrolyte as long as it absorbs the electrolyte and gels. Examples of such a polymer compound include a fluorine-based polymer compound such as polyvinylidene fluoride or a copolymer of vinylidene fluoride and hexafluoropropylene, an ether-based polymer such as polyethylene oxide or a crosslinked product containing polyethylene oxide. A molecular compound, polyacrylonitrile, etc. are mentioned. In particular, a fluorine-based polymer compound is desirable from the viewpoint of redox stability.

  As the solid electrolyte, for example, an organic solid electrolyte in which an electrolyte salt is dispersed in a polymer compound having ion conductivity, or an inorganic solid electrolyte made of ion conductive glass or ionic crystals can be used. At this time, as the polymer compound, for example, an ether polymer compound such as polyethylene oxide or a crosslinked product containing polyethylene oxide, an ester polymer compound such as polymethacrylate, an acrylate polymer compound alone or mixed, Alternatively, it can be used by copolymerizing in the molecule. As the inorganic solid electrolyte, lithium nitride, lithium iodide, or the like can be used.

  Furthermore, for example, in the above embodiments and examples, the case where lithium is used as the electrode reactant has been described. However, other group 1 elements in the long-period periodic table such as sodium (Na) or potassium (K) are used. The present invention can also be applied to the case of using a group 2 element in a long-period periodic table such as magnesium or calcium (Ca), or other light metal such as aluminum, or lithium or an alloy thereof, Similar effects can be obtained. At that time, a negative electrode active material, a positive electrode active material, a solvent, or the like that can occlude and release the electrode reactant is selected according to the electrode reactant.

It is sectional drawing showing the structure of the secondary battery manufactured with the manufacturing apparatus of the electrode which concerns on one embodiment of this invention. It is a figure showing the whole structure of the manufacturing apparatus of the electrode which concerns on one embodiment of this invention. It is sectional drawing which expands and represents a part of positive electrode and negative electrode which are press-processed with the manufacturing apparatus of the electrode shown in FIG. It is a side view showing the structure of the 2nd roll shown in FIG. It is sectional drawing showing the structure of the 2nd roll shown in FIG. It is a figure showing the flow of the manufacturing method of the electrode using the manufacturing apparatus of the electrode shown in FIG. It is a figure showing the manufacturing method of the electrode shown in FIG. 6 in order of a process. In Example 2 of this invention, it is a figure showing the relationship between the generation | occurrence | production position from the exposure area | region boundary line of a protrusion, and its height. In the comparative example 1 of this invention, it is a figure showing the relationship between the generation | occurrence | production position from the exposure area | region boundary line of a protrusion, and its height. In Example 2 of this invention, it is a figure showing the result of the relationship between the number of continuous processes, and the change of the surface temperature in the width direction of a 2nd roll. In Example 3 of this invention, it is a figure showing the result of the relationship between the number of continuous processes, and the change of the surface temperature in the width direction of a 2nd roll. It is sectional drawing for demonstrating the problem of the conventional press equipment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Battery can, 12, 13 ... Insulation board, 14 ... Battery cover, 15 ... Safety valve mechanism, 16 ... Heat sensitive resistance element, 17 ... Gasket, 20 ... Electrode body, 21 ... Positive electrode, 22 ... Negative electrode, 23 ... Separator, 24 ... Center pin, 25 ... Positive electrode lead, 26 ... Negative electrode lead, 100A ... Electrode region, 100B ... Exposed region, 100C ... Step, 100D ... Unpressurized region, 110 ... Current collector, 120 ... Electrode layer, 210 ... Winding Exit part 211 ... Unwinding roll 220 ... 1st pressurizing part 221 ... 1st roll 230 ... 2nd pressurizing part 231 ... 2nd roll 231A ... Inclining part 234 ... Cooling liquid 240 ... Winding Take-up part, 241 ... winding roll, t ... inclination amount.

Claims (5)

A method for producing an electrode in which an electrode layer containing an active material is formed on a part of a current collector,
Pressing the electrode layer provided on the current collector with a first roll;
After pressurizing the electrode layer with the first roll, a region of the current collector that is exposed without the electrode layer being formed is 10N by a second roll having a smaller diameter than the first roll. Pressurizing at a pressure of not less than / cm and not more than 20 N / cm. A battery manufacturing method in which a pair of electrodes in which an electrode layer containing an active material is formed on a part of a current collector is disposed with a separator interposed therebetween,
After pressing an electrode layer provided on the current collector with a first roll on at least one of the pair of electrodes, a region of the current collector that is exposed without forming the electrode layer, A method for producing a battery, characterized by forming by pressing with a second roll having a diameter smaller than that of the first roll at a pressure of 10 N / cm or more and 20 N / cm or less. An electrode manufacturing apparatus in which an electrode layer containing an active material is formed on a part of a current collector,
A first pressurizing unit that pressurizes an electrode layer provided on the current collector with a first roll;
About the electrode pressurized by the first pressurizing unit, a region of the current collector that is exposed without forming the electrode layer is formed by a second roll having a diameter smaller than that of the first roll by 10 N / An electrode manufacturing apparatus comprising: a second pressurizing unit configured to pressurize at a pressure of cm or more and 20 N / cm or less.   The electrode manufacturing apparatus according to claim 3, wherein the second roll has inclined portions with tapered inclinations at both ends in the width direction. The electrode manufacturing apparatus according to claim 3, wherein the second roll has a cooling liquid sealed therein.

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