JP2007335181A - Manufacturing method and device for nonaqueous electrolyte secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid filling method that contributes to improve battery quality and productivity in a nonaqueous electrolyte filling step which are deteriorated due to high density of an active material and an increase in tension at a positive-electrode plate, a negative-electrode plate, and a separator along with the trend of high capacity. <P>SOLUTION: A manufacturing method for a nonaqueous electrolyte secondary battery is composed of a first step for decompressing the inside of a chamber 10 storing a battery container 15, into which an electrode group 16 is inserted, for a fixed period of time by using a vacuum pump 1; a second step in which a gas injection opening/closing valve 6 is opened so as to inject gas soluble in a nonaqueous electrolyte from a gas canister 3 into the chamber 10, a decompression opening/closing valve 4 is closed after a fixed period of time, and the gas injection opening/closing valve 6 is closed after a fixed period of time; a third step for filling the nonaqueous electrolyte into the battery container 10 by using a liquid-filling pump 7 and a liquid-filling nozzle 8; and subsequently, a fourth step in which the battery container is decompressed by using the vacuum pump 1 and the inside of the battery container is returned to an atmospheric pressure after the elapse of a fixed period of time, so as to feed the battery container 15 to the next step. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention provides a method for producing a non-aqueous electrolyte secondary battery capable of efficiently and efficiently injecting a non-aqueous electrolyte into a non-aqueous electrolyte secondary battery capable of achieving high output and high capacity, and its The present invention relates to a manufacturing apparatus.

  In recent years, portable and cordless electronic devices such as AV devices or personal computers and portable communication devices have been rapidly promoted. As power sources for driving these electronic devices, rapid charging is possible and volume energy density and Non-aqueous electrolyte secondary batteries represented by lithium secondary batteries are becoming mainstream as batteries that have both high weight energy density, small size, light weight, and high capacity and can be charged and discharged. Along with the diversification of electronic equipment used, high capacity is required, so the density of the active material is increased, the tightness of the positive electrode plate, the negative electrode plate, and the separator is increased, and accordingly the time for the nonaqueous electrolyte to penetrate is increased. Came to be.

As shown in FIG. 8 for improving productivity, a battery container 106 in which an electrode group 107 is inserted is housed in a chamber 101, and a funnel-like shape capable of collecting a predetermined amount of nonaqueous electrolyte on the battery container 106. The liquid reservoir 102 is attached. Using a liquid injection pump 103, a nonaqueous electrolytic solution is supplied to the liquid storage container 102 and once collected, and the vacuum pump 104 is driven to bring the chamber 101 into a vacuum atmosphere. Remove air from the liquid. Further, a method has been proposed in which the inside of the chamber 101 is once opened to the atmosphere, then pressurized using the pressurizing pump 105, and the nonaqueous electrolytic solution is permeated using the pressure difference between the upper and lower portions of the nonaqueous electrolytic solution. (For example, refer to Patent Document 1).
Japanese Patent Laid-Open No. 7-99050

  However, in the above-described prior art of Patent Document 1, as the capacity increases, the degree of tightness between the positive electrode plate and the negative electrode plate constituting the electrode group and the separator interposed therebetween increases the density of the active material. As time elapses, the time for the nonaqueous electrolyte to permeate becomes longer, and the time for maintaining the vacuum state is extended to promote the permeation of the nonaqueous electrolyte. As a result, the volatilization amount of the non-aqueous electrolyte solution is increased, resulting in variations in the non-aqueous electrolyte solution amount, resulting in increased battery capacity variation.

  The present invention has been made in view of the above-described conventional problems, and after depressurizing the inside of the battery container and replacing the inside of the battery container with a gas that can be dissolved in the non-aqueous electrolyte, the non-aqueous electrolyte is injected, and the battery container It is an object of the present invention to provide a method for manufacturing a non-aqueous electrolyte secondary battery and a manufacturing apparatus therefor, which remove gas that can be dissolved in the remaining non-aqueous electrolyte.

In order to achieve the above object, in the method for producing a non-aqueous electrolyte secondary battery of the present invention, a strip-shaped positive electrode plate and a negative electrode current collector in which a positive electrode mixture layer containing at least a positive electrode active material is formed on a positive electrode current collector. A strip-shaped negative electrode plate in which a negative electrode mixture layer containing at least a negative electrode active material is formed on an electric conductor, and an electrode group wound in a spiral shape with a separator interposed therebetween are inserted into a metal battery container, and the battery A non-aqueous electrolyte secondary battery manufacturing method for sealing an opening of a battery container with a sealing body after injecting a non-aqueous electrolyte into the container, the first step of reducing the pressure in the battery container, and A second step of replacing the inside of the battery container with a gas that can be dissolved in the non-aqueous electrolyte; a third step of injecting the non-aqueous electrolyte into the battery container; and the remaining non-water in the battery container. It is characterized by comprising a fourth step of removing gas that can be dissolved in the electrolyte. .

  According to the present invention, after depressurizing the inside of the battery container and replacing it with a gas that can be dissolved in the non-aqueous electrolyte, the non-aqueous electrolyte is injected into the battery container and dissolved in the remaining non-aqueous electrolyte in the battery container. By removing possible gas, it is possible to shorten the time for maintaining and infiltrating a specified amount of nonaqueous electrolyte in a vacuum state for injecting and infiltrating, and increase the volatilization amount of the nonaqueous electrolyte The variation in the amount of the non-aqueous electrolyte caused by this can be suppressed, and the quality and productivity can be improved.

  In the first aspect of the present invention, a strip-like positive electrode plate in which a positive electrode mixture layer containing at least a positive electrode active material is formed on a positive electrode current collector and a negative electrode mixture layer containing at least a negative electrode active material on a negative electrode current collector are formed. A non-aqueous solution in which a non-aqueous electrolyte solution is injected into a battery container by inserting an electrode group formed by winding a strip-shaped negative electrode plate into a metal battery container with a separator interposed therebetween A method for producing an electrolyte secondary battery, wherein a first step of decompressing the battery container, a second step of substituting the inside of the battery container with a gas that can be dissolved in a non-aqueous electrolyte, and then a battery container A non-aqueous electrolyte solution in the atmosphere by comprising a third step of injecting a non-aqueous electrolyte solution into the inside and a fourth step of removing gas that can be dissolved in the non-aqueous electrolyte solution remaining in the battery container. Evaporation of non-aqueous electrolyte without being left in the middle or under reduced pressure for a long time By suppressing the components change in the pouring weight variation and a non-aqueous electrolyte solution with a high instilling accuracy and instilling of securing the components maintain a non-aqueous electrolyte solution is possible.

  In the second invention of the present invention, by using carbon dioxide as a gas that can be dissolved in the nonaqueous electrolyte inside the battery container, the penetration of the nonaqueous electrolyte into the electrode group is promoted and the permeation time is shortened. In addition, carbon dioxide dissolved in the nonaqueous electrolytic solution forms a film, so that reaction unevenness on the electrode plate surface can be suppressed, and battery characteristics can be improved.

  In the third invention of the present invention, in the third step, after injecting the non-aqueous electrolyte into the battery container containing the electrode group, the inside of the battery container is pressurized to thereby convert the non-aqueous electrolyte into the positive electrode. Penetration to the deep part of the composite material layer and the negative electrode composite material layer can be achieved, and variations in battery capacity can be suppressed.

  In the fourth invention of the present invention, in the fourth step, as a method of removing the gas dissolved in the nonaqueous electrolyte remaining in the battery container, the inside of the battery container is reduced in pressure by reducing the pressure in the battery container. It is possible to suppress gas generation during charging by removing moisture contained in the battery.

  In the fifth invention of the present invention, in the fourth step, the non-aqueous electrolyte is further penetrated to the deep part of the positive electrode mixture layer and the negative electrode mixture layer by pressurizing the inside of the battery container with air after decompression. Therefore, variation in battery capacity can be suppressed.

  In a sixth aspect of the present invention, there is provided a chamber for housing a battery container into which an electrode group formed by winding a positive electrode plate and a negative electrode plate in a spiral shape with a separator interposed therebetween, A decompression unit connected to a chamber for exhausting the gas in the chamber and the decompression unit, a decompression on-off valve for opening and closing the decompression unit, a gas cylinder connected to the inside of the battery container and the chamber for replacing the gas in the chamber, and a gas cylinder A gas injection on / off valve for opening and closing the injection of gas to be replaced, a pressurizing unit connected to a chamber for pressurizing the inside of the battery container and the chamber, a pressurizing on / off valve for opening and closing the pressurizing unit, and a battery container A non-aqueous electrolyte secondary battery comprising an injection pump for supplying a non-aqueous electrolyte quantitatively and an injection nozzle for injecting the non-aqueous electrolyte from the injection pump into the battery container A series of works by manufacturing equipment Shortens the injection time, and as a result, improves the productivity and quality by reducing the loss and variation of the non-aqueous electrolyte, and improves the battery characteristics by improving the permeability of the non-aqueous electrolyte. Injection is possible.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. An embodiment shown below shows a manufacturing apparatus for explaining the present invention in detail. The present invention provides a structure and manufacturing apparatus for a cylindrical non-aqueous electrolyte secondary battery. Not specific.

  FIG. 1 is a flowchart of a liquid injection process in the method for manufacturing a nonaqueous electrolyte secondary battery according to an embodiment of the present invention. As shown in FIG. 1, in the first step, the inside of the chamber containing the battery container in which the electrode group is inserted is depressurized for a certain time using a vacuum pump. Next, in the second step, the gas injection on-off valve is opened to inject a gas that can be dissolved in the non-aqueous electrolyte in the chamber, the decompression on-off valve is closed after a certain time, and the gas injection on-off is opened after a certain time. Close the valve.

  Next, in the third step, a non-aqueous electrolyte is injected into the battery container using an injection pump and a nozzle. Next, in the fourth step, the pressure is reduced using a vacuum pump or a pressure pump. After a lapse of a certain time, the pressure is returned to atmospheric pressure, the battery container is taken out, and sent to the next waiting process for permeation.

  FIG. 2 is a schematic view of an apparatus for producing a nonaqueous electrolyte secondary battery (hereinafter referred to as a secondary battery) of the present invention. In FIG. 2, a vacuum pump 1 for depressurization, a pressurization pump 2 for pressurization, and a gas cylinder 3 containing a gas that can be dissolved in a nonaqueous electrolytic solution are connected to a battery container 15 in which an electrode group 16 is inserted. It is connected to the housed chamber 10.

  Further, a pressure reducing on / off valve 4 for opening and closing a vacuum is connected to the vacuum pump 1 connected to the chamber 10, a pressure on / off valve 5 is connected to the pressure pump 2, and a gas injection on / off valve 6 is connected to the gas cylinder 3. Are connected to each other. Further, an injection nozzle 7 for injecting the non-aqueous electrolyte into the battery container 15 accommodated in the chamber 10 is connected to the injection pump 7 for feeding the non-aqueous electrolyte, and the injection pump 7 is non-aqueous. It is connected to a non-aqueous electrolyte tank 9 in which the electrolyte is stored.

  FIG. 7 shows a metal battery container 15 in which the electrode group 16 is inserted. One end of a lead 17 for collecting current is joined to the electrode group 16, and a sealing plate 18 for sealing the battery container 15 is joined to the opposite end of the lead 17 joined to the electrode group 16. .

  Next, the order of injecting the non-aqueous electrolyte into the battery container 15 will be described with reference to FIG. First, in the first step, the battery container 15 in which the electrode group 16 is inserted is housed in the chamber 10, the vacuum pump 1 is driven, and the pressure reducing on-off valve 4 is opened. The air in the chamber 10 and the battery container 15 is removed by opening for a certain time. At that time, it is desirable to remove the space between the positive electrode plate, the negative electrode plate and the separator wound in a spiral shape in the electrode group 16 in the battery container 15 and the air in the gap between the battery container 15 and the electrode group 16.

  Next, in the second step, the gas injection on-off valve 6 is opened, and a dissolvable gas composed of carbon dioxide is injected into the non-aqueous electrolyte into the chamber 10 and the battery container 15 from which air has been removed in the first step. . After a certain time has elapsed, the pressure reducing on / off valve 4 is closed, and a gas that can be dissolved in the nonaqueous electrolyte is further injected into the chamber 10 and the battery container 15, and after a certain time has elapsed, the gas injection on / off valve 6 is closed. Also in this case, it dissolves in the non-aqueous electrolyte up to the space between the positive electrode plate and the negative electrode plate wound in a spiral shape in the electrode group 16 in the battery container 15 and the gap between the battery container 15 and the electrode group 16. It is desirable to ensure a time during which a gas that can be inserted is inserted.

  Thereafter, in the third step, the nonaqueous electrolyte is injected into the battery container 15 from the nonaqueous electrolyte tank 9 through the injection nozzle 8 by the injection pump 7. Thereafter, the pressurization on-off valve 5 is opened, and the inside of the chamber 10 and the battery container 15 is pressurized by the pressurizing pump 2. Accordingly, it is possible to further promote the penetration of the nonaqueous electrolytic solution into the electrode group 16.

  Further, in the fourth step, the vacuum pump 1 is driven and the pressure reducing on-off valve 4 is opened to remove the gas that can be dissolved in the remaining non-aqueous electrolyte in the chamber 10 and the battery container 15. Then, the vacuum pump 1 is stopped, the pressure reducing on-off valve 4 is closed, and the series of steps is completed. Alternatively, in the fourth step, after depressurization, the pressurization pump 2 is further driven to open the pressurization on-off valve 5, the pressurization pump 2 is stopped after a certain period of time, and the pressurization on-off valve 5 is closed. This step is completed. The gas is not limited to carbon dioxide as long as it is a gas that can be dissolved in the non-aqueous electrolyte.

  Next, a method for manufacturing a non-aqueous electrolyte secondary battery and its manufacturing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. EXAMPLES Examples of the present invention will be described in detail below, but these do not limit the present invention.

  As shown in FIG. 7, a general lithium ion secondary battery having a diameter of 18 mm and a height of 65 mm was used. In addition, carbon dioxide is used as a gas that can be dissolved in the nonaqueous electrolytic solution, and the weight of the battery container 15 in which the electrode group 16 is inserted in advance is measured in an uninjected state.

  2, first, in the first step, the battery container 15 in which the electrode group 16 is inserted is housed in the chamber 10, and the state diagram of the pressure in the battery container 15 and the chamber 10 in FIG. 3. As shown in FIG. 4, the pressure reducing on-off valve 4 is opened, and the vacuum pump 1 is used to reduce the pressure at a vacuum degree of −100 kPa for 60 seconds. Next, in the second step, the gas injection on / off valve 6 was opened and carbon dioxide injection was started at 50 Kpa, and after 5 seconds, the pressure reducing on / off valve 4 was closed.

  After a further 60 seconds, the gas injection on-off valve 6 was closed. In the third step, 5.2 g of nonaqueous electrolytic solution was injected into the battery container 15 from the nonaqueous electrolytic tank 9 through the liquid injection nozzle 8 with the liquid injection pump 7. Next, in the fourth step, the pressure reducing on / off valve 4 is opened, the vacuum pump 1 is used to reduce the pressure to -90 Kpa, and after 60 seconds, the vacuum pump 1 is stopped and returned to atmospheric pressure. Closed. Then, the battery container 15 which measured the time for the non-aqueous electrolyte to penetrate into the electrode group 16 and the weight immediately after the completion of the penetration was taken as Example 1.

  As Example 2 of the present invention, a non-aqueous electrolyte was injected in the same manner as Example 1 up to the third step. Thereafter, as shown in the state diagram of the pressure in the battery container 15 and the chamber 10 in FIG. 4, the pressure on-off valve 5 is opened in the fourth step, and air is injected using the pressure pump 2. The pressure was increased to 50 kPa, and after 60 seconds, the pressure pump 2 was stopped and returned to atmospheric pressure, and the pressure on-off valve 5 was closed. Then, the battery container 15 which measured the time for the non-aqueous electrolyte to penetrate into the electrode group 16 and the weight immediately after the completion of the penetration was taken as Example 2.

  As Example 3 of the present invention, carbon dioxide was injected in the same manner as in Example 1 until the second step. Next, as shown in the state diagram of the pressure in the battery container 15 and the chamber 10 in FIG. 5, in the third step, the liquid injection nozzle 8 is inserted into the battery container 15 from the nonaqueous electrolyte tank 9 by the liquid injection pump 7. After injecting 5.2 g of non-aqueous electrolyte, the pressure on / off valve 5 is opened, the pressure pump 2 is used to pressurize the battery container 15 to 50 kPa, and the pressure pump 2 is stopped after 10 seconds. Then, the pressure on-off valve 5 was closed to return to atmospheric pressure.

  Further, in the fourth step, the pressure reducing on / off valve 4 is opened, the pressure is reduced to -90 Kpa using the vacuum pump 1, and after 60 seconds, the vacuum pump 1 is stopped and returned to atmospheric pressure, and the pressure reducing on / off valve 4 is closed. It was. Then, the battery container 15 which measured the time for the non-aqueous electrolyte to penetrate into the electrode group 16 and the weight immediately after the completion of the penetration was taken as Example 3.

  As Example 4 of the present invention, a non-aqueous electrolyte was injected in the same manner as Example 3 up to the third step. Thereafter, as shown in the state diagram of the pressure in the battery container 15 and the chamber 10 in FIG. 6, the pressure reducing on / off valve 4 is opened in the fourth step, and the vacuum pump 1 is used to reduce the pressure to −90 Kpa. 60 seconds later, the vacuum pump 1 is stopped and returned to atmospheric pressure, the pressure reducing on-off valve 4 is closed, the pressure on-off valve 5 is opened, air is injected using the pressure pump 2, and the pressure is increased to 50 kPa. After 60 seconds, the pressurizing pump 2 was stopped and returned to atmospheric pressure, and the pressurizing on-off valve 5 was closed. Then, the battery container 15 which measured the time for the nonaqueous electrolyte to permeate into the electrode group 16 and the weight immediately after the completion of the permeation was defined as Example 4.

(Comparative example)
Injection was performed using an injection apparatus as shown in FIG. The weight of the battery container 106 in which the electrode group 107 is inserted in advance is measured in an uninjected state. A battery container 106 in which an electrode group 107 is inserted is accommodated in the chamber 101, and 5.2 g of a non-aqueous electrolyte is injected into the funnel-shaped liquid reservoir container 102 mounted on the upper part of the battery container 106 by using an injection pump 103. , Collect. The three-way valve 108 for reducing and increasing pressure is closed to the pressure reducing side, and the vacuum pump 104 is driven to reduce the pressure in the chamber 101 to −90 kPa.

  After 120 seconds have elapsed, the vacuum pump 104 is stopped, the pressure-reduction / pressure switching three-way valve 108 is opened to the atmosphere opening side, and the inside of the chamber 101 is once returned to atmospheric pressure. After that, the pressure-reduction / pressure switching three-way valve 108 is closed on the pressure side and pressurized to 50 kPa using the pressure pump 105, and after 60 seconds, the pressure pump 105 is stopped and the pressure-reduction pressure switching three-way valve 108 is opened to the atmosphere open side. Open and return the chamber 101 to atmospheric pressure. Then, the battery container 106 which measured the time which nonaqueous electrolyte solution osmose | permeates in the electrode group 107, and the weight immediately after completion | finish of infiltration was made into the comparative example.

  In order to compare the accuracy in the nonaqueous electrolyte injection time of Examples 1 to 4 and the comparative example and the amount of the nonaqueous electrolyte lost to the apparatus due to adhesion or volatilization during injection, the following evaluation was performed. The results are shown in (Table 1).

  The injection time, the loss amount of the non-aqueous electrolyte, and the variation in the injection amount shown in Table 1 were measured as follows. The time for injecting the liquid was measured as the time of penetration into the electrode group in the battery container. The accuracy of pouring is calculated by adding 5.2 g of the weight of the non-aqueous electrolyte to the weight of the battery container that has been filled with the non-aqueous electrolyte and the weight of the battery container that has not been filled with the non-aqueous electrolyte. The difference from the weight was taken as the injected amount, and the ratio to the injected non-aqueous electrolyte amount was expressed.

  Each example was compared with the 30 battery containers implemented. The amount of loss of the non-aqueous electrolyte is the weight of the non-aqueous electrolyte in addition to the weight of the battery container that has been injected with the non-aqueous electrolyte and the weight of the battery container that has not been injected with the non-aqueous electrolyte. Assuming that the difference from the weight of 5.2 g was added, the comparison was made in each example.

  From the results of (Table 1), Examples 1 to 4 in the liquid injection method of the present invention were able to reduce the liquid injection time and the loss amount and liquid injection amount variation compared to the comparative example. In particular, in Example 3, in addition to the effect of Example 1, it is possible to promote the penetration of the nonaqueous electrolytic solution by adding pressurization after the injection in the third step.

  Also in Example 4, in addition to the effect of Example 3, it is possible to promote the penetration of the non-aqueous electrolyte by adding the pressure after the pressure reduction in the fourth step. In the comparative example, the non-aqueous electrolyte is infiltrated into the battery container only by the pressure difference between the upper and lower sides of the non-aqueous electrolyte, but the air and the non-aqueous electrolyte are not removed because the air in the battery container is not completely removed. It is difficult to proceed with replacement, and it is necessary to wait for penetration by natural replacement.

  As a result, it takes time to complete the permeation, and accordingly, the loss amount of the non-aqueous electrolyte due to volatilization increases, which causes the injection amount to vary. In contrast, the method of the present invention not only removes the air in the battery container, but also substitutes carbon dioxide, which is a gas that can be dissolved in the non-aqueous electrolyte, so that the non-aqueous electrolyte is more contained in the battery container. Penetration and the time until the completion of penetration can be shortened. As a result, variations in loss and liquid injection can be reduced, and quality and productivity can be improved.

  According to the present invention, the replacement of the gas in the battery container and the non-aqueous electrolyte is further promoted by replacing the inside of the battery container in which the electrode group is inserted with a gas that can be dissolved in the non-aqueous electrolyte. The injection time can be shortened, and as a result, the loss amount of the nonaqueous electrolyte and the injection amount variation can be suppressed, which is useful for improving productivity and quality and reducing the manufacturing cost.

Process flowchart showing an embodiment of the present invention The schematic diagram of the manufacturing apparatus which shows embodiment of this invention State diagram of pressure in battery container and chamber in embodiment 1 of the present invention State diagram of pressure in battery container and chamber in embodiment 2 of the present invention State diagram of pressure in battery container and chamber in embodiment 3 of the present invention State diagram of pressure in battery container and chamber in embodiment 4 of the present invention Schematic diagram of the electrode group inserted in the battery container of the present invention Schematic diagram of a conventional injection device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum pump 2 Pressurization pump 3 Gas cylinder 4 Pressure reducing on-off valve 5 Pressurizing on-off valve 6 Gas injection on-off valve 7 Injection pump 8 Injection nozzle 9 Non-aqueous electrolyte tank 10 Chamber 15 Battery container 16 Electrode group 17 Lead 18 Sealing plate

Claims (6)

  Between the strip-shaped positive electrode plate in which the positive electrode mixture layer containing at least the positive electrode active material is formed on the positive electrode current collector and the strip-shaped negative electrode plate in which the negative electrode mixture layer including at least the negative electrode active material is formed on the negative electrode current collector. After inserting a non-aqueous electrolyte into the battery container, the electrode group formed by winding the separator in a spiral shape with a separator interposed between the battery container, and then opening the battery container with a sealing body A non-aqueous electrolyte secondary battery manufacturing method for sealing a battery, wherein a first step of depressurizing the inside of the battery container, and then replacing the inside of the battery container with a gas that can be dissolved in the non-aqueous electrolyte. A second step, a third step of injecting the non-aqueous electrolyte into the battery container, and a fourth step of removing gas that can be dissolved in the non-aqueous electrolyte remaining in the battery container. The manufacturing method of the nonaqueous electrolyte secondary battery characterized by comprising a process.   The method for producing a non-aqueous electrolyte secondary battery according to claim 1, wherein carbon dioxide is used as a gas that can be dissolved in the non-aqueous electrolyte in the battery container.   2. The non-aqueous electrolyte secondary according to claim 1, wherein, in the third step, the inside of the battery container is pressurized after injecting the non-aqueous electrolyte into the battery container containing the electrode group. Battery manufacturing method.   The nonaqueous electrolytic solution according to claim 1, wherein the inside of the battery container is depressurized as a method of removing gas that can be dissolved in the nonaqueous electrolytic solution remaining in the battery container in the fourth step. A method for manufacturing a secondary battery.   The method for producing a non-aqueous electrolyte secondary battery according to claim 1, wherein, as the fourth step, the inside of the battery container is pressurized after decompression. A chamber for storing a battery container in which an electrode group formed by spirally winding a positive electrode plate and a negative electrode plate with a separator interposed therebetween, and exhausting gas in the battery container and the chamber; A pressure reducing part for reducing pressure, a pressure reducing on-off valve for opening and closing the pressure reducing part, a gas cylinder connected to the chamber for replacing the gas in the battery container and the chamber, and injection of gas for replacement from the gas cylinder A gas injection on-off valve that opens and closes the battery, a pressurization unit connected to the chamber for pressurizing the inside of the battery container and the chamber, a pressurization on-off valve for opening and closing the pressurization unit, and non-water in the battery container A non-aqueous electrolyte secondary battery comprising a liquid injection pump for supplying a constant amount of an electrolyte and a liquid injection nozzle for injecting the non-aqueous electrolyte from the liquid injection pump into a battery container Manufacturing equipment.

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