JP2007173062A - Method and apparatus of producing flat battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus of producing flat batteries which assures batteries of high liquid injection accuracy, by impregnating an electrode assembly placed in a housing case with nonaqueous electrolyte solution, without leaving it standing in the atmosphere or in a depressurized condition over long times, to suppress variation in the amount of liquid injection of the electrolyte solution and component changes in the solution. <P>SOLUTION: When nonaqueous electrolyte solution is sucked or injected in an upper case 1 in which the electrode assembly 2 is placed, the solution is temporarily stored in a syringe 11 for the nonaqueous electrolyte solution sealed with a injection piston 8 at a suction stage A. After it is moved to an injection stage B, the solution is supplied by the injection piston 8 at high accuracy. When the solution comes into contact with an injection guide ring 13, the surface tension of the solution, generated on the electrode assembly 2, is broken and by covering the entire circumference and entire surface, the assembly 2 is covered and the case 1 and the assembly 2 is filled with the solution. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a flat battery and an apparatus for manufacturing the same, which are suitable for quickly impregnating an electrode body with a non-aqueous electrolyte in a case of the flat battery containing the electrode body.

  In recent years, coin-type batteries represented by flat batteries tend to have an increasing demand for long-term reliable coin-type batteries with a 10-year warranty that can withstand harsh environments as the main power source for vehicles and watches. In the manufacturing process of coin-type batteries, it is required to manufacture products with little variation to ensure stable quality of coin-type batteries. Especially, the amount of non-aqueous electrolyte injected is a storage characteristic to ensure long-term storage. The accuracy of the strict injection volume with little variation is required.

  A coin-type battery is prepared by injecting a non-aqueous electrolyte into an upper case that houses an electrode body having a laminated structure of a negative electrode body, a positive electrode body, and a separator, and then covering the upper case with the lower case and covering the opening of the lower case. It is manufactured by caulking and sealing. When the non-aqueous electrolyte is injected into the upper case, it takes time to impregnate the electrode body made of a high-density active material with the non-aqueous electrolyte. Further, if the nonaqueous electrolytic solution is left for a long period of time to impregnate the nonaqueous electrolytic solution, the nonaqueous electrolytic solution evaporates due to vaporization of the nonaqueous electrolytic solution, resulting in variations in the amount of the nonaqueous electrolytic solution and component changes.

As a conventional non-aqueous electrolyte injection method, as shown in FIG. 4, a predetermined amount of non-aqueous electrolyte is supplied to the temporary storage chamber 105 by a metering nozzle 112, and the piston 103 is used as a temporary storage chamber. The upper end of 105 is closed, and the air in the temporary storage chamber 105 is exhausted from the exhaust port 109 at the upper end of the piston 103 to reduce the pressure. Further, the air in the temporary storage chamber 105 and the decompression chamber 104 is exhausted through the exhaust port 106, the inside of the case 101 is decompressed, and the non-aqueous electrolyte is pushed out by the piston 103 inserted into the temporary storage chamber 105. A method of injecting a predetermined amount of non-aqueous electrolyte into the case 101 in the decompression chamber 104 in a decompressed state by passing through the liquid injection tube 102 has been proposed (see, for example, Patent Document 1).
JP 2004-055238 A

  However, in the conventional technique shown in the above-mentioned patent document, when the nonaqueous electrolytic solution is discharged from the liquid injection pipe 102 through the temporary storage chamber 105 as shown in FIG. 4, the nonaqueous electrolytic solution is temporarily stored in the temporary storage chamber 105. And non-aqueous electrolysis of a flat battery having a small diameter due to variations in the non-aqueous electrolyte that is injected to adhere to the surface of the liquid injection tube 102 or to the lower surface wetted surface 111 of the liquid injection nozzle 110. In a small flat battery that requires a small amount of liquid or high accuracy, it has been difficult to inject a small amount or high accuracy.

The present invention has been made in view of the above-described conventional problems, and the nonaqueous electrolyte syringe absorbs itself from the nonaqueous electrolyte tank and injects the nonaqueous electrolyte stored in the nonaqueous electrolyte syringe. By using the same mechanism to absorb and inject nonaqueous electrolyte, external factors such as the nonaqueous electrolyte metering pump used to supply the nonaqueous electrolyte become unnecessary, and the nonaqueous electrolyte metered supply There is no variation in the amount of non-aqueous electrolyte supplied by the pump. In addition, when impregnating the non-aqueous electrolyte into the electrode body housed in the upper case, the non-aqueous electrolyte that has become spherical due to surface tension is broken, and the entire electrode body is covered with the non-aqueous electrolyte. As a result, the non-aqueous electrolyte will not be left for a long time in the atmosphere or under reduced pressure, and variations in the injection volume due to evaporation of the non-aqueous electrolyte and changes in the components of the non-aqueous electrolyte are suppressed. Thus, an object of the present invention is to provide a method for manufacturing a flat battery and a manufacturing apparatus therefor, which ensure high injection accuracy and component maintenance of a nonaqueous electrolyte.

  In order to achieve the above object, the present invention provides an electrode body in which a positive electrode material made of a positive electrode active material and a negative electrode material made of a material capable of holding lithium are stacked with a separator interposed therebetween. A method of manufacturing a flat battery in which a non-aqueous electrolyte is injected after sealing in an upper case having an insulating gasket at the peripheral edge of the part, and the opening of the upper case is sealed with a container-like lower case, the electrode body The non-aqueous electrolyte stored in the non-aqueous electrolyte syringe is stored in the non-aqueous electrolyte syringe after the non-aqueous electrolyte syringe absorbs itself from the non-aqueous electrolyte tank. It is characterized by impregnating the electrode body while pouring and breaking the nonaqueous electrolyte that has become spherical due to surface tension and covering the entire electrode body with the nonaqueous electrolyte.

  According to the present invention, the non-aqueous electrolyte solution in which the upper case containing the electrode body is housed in the airtight chamber and the airtight chamber is depressurized, and then the nonaqueous electrolyte syringe absorbs itself and is stored in the nonaqueous electrolyte syringe. The nonaqueous electrolyte syringe that has become spherical due to the surface tension is broken, and the electrode body is impregnated while covering the entire electrode body with the nonaqueous electrolyte solution. In order to fulfill the role and the role of the liquid injection pump, variations in the supply amount of the non-aqueous electrolyte are suppressed. In addition, since the impregnation time of the nonaqueous electrolyte into the electrode body is completed in a short time, it is not necessary to leave it for a long time in atmospheric pressure or in a reduced pressure state. Variation in the amount can be suppressed. In addition, it is possible to suppress changes in the components of the non-aqueous electrolyte.

  In the first invention of the present invention, a positive electrode material composed of a positive electrode active material, a negative electrode material composed of a material capable of holding lithium as an active material, and an electrode body formed by laminating a separator therebetween are provided in the opening. A method for producing a flat battery, which is stored in an upper case having an insulating gasket at a peripheral edge, and then injected with a non-aqueous electrolyte and seals the opening of the upper case with a container-like lower case, the electrode body The non-aqueous electrolyte stored in the non-aqueous electrolyte syringe is stored in the non-aqueous electrolyte syringe after being stored in the non-aqueous electrolyte syringe by storing the upper case in the air-tight chamber and reducing the pressure of the air-tight chamber. The amount of non-aqueous electrolyte supplied is reduced by breaking the non-aqueous electrolyte that has become spherical due to surface tension and impregnating the electrode body while covering the entire electrode body with the non-aqueous electrolyte. Variations are suppressed and the atmosphere The non-aqueous electrolyte is not exposed to the pressure for several tens of seconds or in a reduced pressure state for a long time, and it prevents the non-aqueous electrolyte from splashing and the non-aqueous electrolyte components from evaporating. It becomes possible to suppress variations in the amount and changes in the components of the non-aqueous electrolyte.

  In the second invention of the present invention, the nonaqueous electrolyte syringe is filled with the nonaqueous electrolyte solution so as not to include air, and the nonaqueous electrolyte solution is injected and impregnated into the electrode body in the upper case. The non-aqueous electrolyte is not exposed to atmospheric pressure, it is possible to suppress the evaporation of the components of the non-aqueous electrolyte, and to suppress variations in the amount of the non-aqueous electrolyte and changes in the components of the non-aqueous electrolyte. .

  In the third invention of the present invention, by adjusting the temperature of the non-aqueous electrolyte in the non-aqueous electrolyte tank and injecting and impregnating the non-aqueous electrolyte into the electrode body in the upper case from the injection nozzle, By maintaining the temperature of the non-aqueous electrolyte at a predetermined temperature, there is an effect of reducing the viscosity of the non-aqueous electrolyte, and the impregnation property to the electrode body can be further improved.

In the fourth invention of the present invention, the nonaqueous electrolyte supplied to the nonaqueous electrolyte storage tank in the nonaqueous electrolyte tank is overflowed and recovered in the nonaqueous electrolyte recovery layer in the nonaqueous electrolyte tank, By always sucking liquid into the non-aqueous electrolyte syringe while keeping the liquid level of the non-aqueous electrolyte in the non-aqueous electrolyte storage tank constant, the mixture of air in the non-aqueous electrolyte syringe is prevented and only the non-aqueous electrolyte is used. By filling it, it becomes possible to ensure high liquid injection accuracy of the non-aqueous electrolyte.

  According to a fifth aspect of the present invention, a positive electrode material and a negative electrode material housed in an upper case on a container, an electrode body laminated with a separator interposed therebetween, an airtight chamber for housing the upper case, and a temperature adjusting unit are provided. An aqueous electrolyte tank, a nonaqueous electrolyte syringe with a liquid injection piston that extrudes the temporarily stored nonaqueous electrolyte, and a nonaqueous electrolyte syringe consisting of an injection pipe and an injection guide ring The non-aqueous electrolyte formed into a spherical shape due to the surface tension on the electrode body is formed by the liquid nozzle, the piston drive section that operates the liquid injection piston, and the pressure adjustment section connected to the airtight chamber. It is possible to impregnate the electrode body while covering the whole electrode body with a non-aqueous electrolyte, suppressing variations in the amount of non-aqueous electrolyte due to adhesion of the non-aqueous electrolyte and evaporation of non-aqueous electrolyte components, Non-aqueous electrolyte amount variation, non It is possible to suppress the change in the components of the electrolyte.

  In the sixth aspect of the present invention, a non-aqueous electrolyte tank provided with a temperature adjustment heater as a temperature adjustment unit and a temperature adjustment controller, a non-aqueous electrolyte storage tank and a non-aqueous electrolyte in the non-aqueous electrolyte tank The temperature adjustment heater and temperature installed in the non-aqueous electrolyte tank are configured by a recovery tank and a supply nozzle connected to the non-aqueous electrolyte storage tank that absorbs the non-aqueous electrolyte into the non-aqueous electrolyte syringe. The temperature of the non-aqueous electrolyte can be controlled by the adjustment controller, and the viscosity of the non-aqueous electrolyte can be lowered to improve the impregnation property to the electrode body.

  In the seventh aspect of the present invention, the outer dimension of the injection guide ring is configured within the range from the outer dimension of the electrode body accommodated in the upper case to the inner diameter dimension of the upper case, and the tip of the injection guide ring Since the inner surface of the electrode has a tapered shape, it becomes a spherical shape due to surface tension on the electrode body, breaks the nonaqueous electrolyte that has spread out so as to protrude from the outer shape of the electrode body, and covers the entire electrode body with the nonaqueous electrolyte. The body can be impregnated, and the non-aqueous electrolyte can be impregnated in a short time without adhering to the injection guide ring.

  In the eighth aspect of the present invention, since the non-aqueous electrolyte syringe has variable means for varying the liquid absorption amount and the liquid injection amount, the amount of the non-aqueous electrolyte solution that has been difficult can be reduced. Various conditions can be changed, and there is no need to manufacture a metering pump or injection mechanism according to a predetermined amount of non-aqueous electrolyte or replacement with a dedicated device.

  In the ninth aspect of the present invention, the non-aqueous electrolyte in the non-aqueous electrolyte storage tank in the non-aqueous electrolyte tank is overflowed so that the liquid level of the non-aqueous electrolyte is always kept constant, and the non-aqueous electrolyte is stored. Since the non-aqueous electrolyte solution is supplied to the non-aqueous electrolyte syringe through a supply nozzle in which the liquid level of the non-aqueous electrolyte connected to the tank is always kept constant, It can be filled with a water electrolyte, and air can be prevented from being mixed during liquid absorption, and a highly accurate nonaqueous electrolyte can be supplied to the nonaqueous electrolyte syringe.

  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, and the present invention specifies the structure and manufacturing apparatus of a flat battery as follows. is not. For example, FIG. 1 is a schematic view of a flat battery manufacturing apparatus showing a state of a liquid absorption stage for absorbing a nonaqueous electrolyte and a liquid injection stage for injecting liquid according to an embodiment of the present invention.

As shown in FIG. 1, in the manufacturing apparatus of the present invention, the liquid absorption stage A for absorbing the nonaqueous electrolyte and the liquid injection stage B for injecting the liquid into the upper case containing the electrode body are separately provided. Liquid absorption and liquid injection are performed only by the non-aqueous electrolyte liquid injection unit 7. The nonaqueous electrolyte solution injection unit 7 includes an airtight chamber 10 that places the upper case 1 in which the electrode group 2 is housed in a reduced pressure state or an atmospheric pressure state, and a nonaqueous electrolyte solution that temporarily stores the nonaqueous electrolyte solution. A non-aqueous electrolyte composed of a syringe 11, an injection piston 8 having an O-ring 5 that extrudes the electrolyte by applying pressure to the non-aqueous electrolyte, an injection pipe 14, and an injection guide ring 13 is discharged. And a liquid injection nozzle 6.

  The liquid injection stage A for injecting a non-aqueous electrolyte includes a non-aqueous electrolyte tank 16, and a non-aqueous electrolyte solution feeding part (not shown) and a non-aqueous electrolyte are provided in the non-aqueous electrolyte tank 16. A non-aqueous electrolyte storage tank 27 connected via the supply pipe 17 and a non-aqueous electrolyte recovery tank 28 for recovering the non-aqueous electrolyte overflowed from the non-aqueous electrolyte storage tank 27 are divided. Further, a temperature adjusting heater 20 for warming the non-aqueous electrolyte is built in the non-aqueous electrolyte tank 16, and the temperature adjusting heater 20 adjusts the temperature by the temperature adjustment controller 18. Further, the non-aqueous electrolyte storage tank 27 is communicated with a supply nozzle 19 that supplies the non-aqueous electrolyte to the non-aqueous electrolyte injection section 7, and the liquid level of the non-aqueous electrolyte in the non-aqueous electrolyte storage tank 27. Is reflected on the liquid level of the non-aqueous electrolyte in the liquid injection nozzle 19.

  Further, the injection pipe 14 of the moved non-aqueous electrolyte injection section 7 is inserted into the injection nozzle 19, and the servo motor 21 is injected via the connecting shaft 25 of the piston drive section 29 that drives the injection piston 8. The structure is connected to the piston 8.

  Next, in the liquid injection stage B for injecting the liquid into the upper case 1 containing the electrode body 2, the base 4 for holding the upper case 1 is installed. The base 4 includes a base 36 and a case holder 37. A ring 15 is fitted, and the airtight chamber 10 of the nonaqueous electrolyte solution injection unit 7 is connected. In addition, a piston drive unit 29 that is connected to the injection piston 8 of the non-aqueous electrolyte injection unit and drives the injection piston 8 and a pressure adjustment unit 26 that adjusts the pressure in the airtight chamber 10 are provided.

  As described above, in the manufacturing apparatus of the present invention, the liquid absorption stage A that absorbs the non-aqueous electrolyte and the liquid injection stage B that injects the liquid into the upper case 1 housing the electrode body 2 are separately provided. This is an apparatus for manufacturing a flat battery in which only the water electrolyte solution injection part 7 absorbs and injects liquid, and this device is used to supply a nonaqueous electrolyte fixed amount used for supplying the nonaqueous electrolyte shown in the conventional method. An external factor such as a pump becomes unnecessary, and variation in the amount of non-aqueous electrolyte supplied by the non-aqueous electrolyte fixed supply pump can be further suppressed, so that high-precision liquid injection is possible.

  In the liquid absorption stage A, the degassed non-aqueous electrolyte sent from the non-aqueous electrolyte feed section (not shown) through the non-aqueous electrolyte supply pipe 17 is transferred to the non-aqueous electrolyte storage tank 27. In order to keep the liquid level of the non-aqueous electrolyte supplied in the supply nozzle 19 constant, the non-aqueous electrolyte storage tank 27 communicated with the supply nozzle 19 is filled with the non-aqueous electrolyte until it overflows, The overflowed non-aqueous electrolyte is recovered in the non-aqueous electrolyte recovery tank 28 and sent to the non-aqueous electrolyte solution feeding section. As a result, the liquid level of the non-aqueous electrolyte in the supply nozzle 19 is always kept constant, and even when the liquid is sucked from the injection pipe 14 of the non-aqueous electrolyte syringe 11, no air biting occurs. The water electrolyte can be filled and stored in the non-aqueous electrolyte syringe 11.

  In addition, when the nonaqueous electrolyte is sucked into the nonaqueous electrolyte syringe 11, the nonaqueous electrolyte is supplied to the nonaqueous electrolyte storage tank 27 from the nonaqueous electrolyte supply pipe 17 faster than the speed at which the nonaqueous electrolyte decreases. Supply. Here, an overflow is detected by a sensor, the non-aqueous electrolyte solution feeding part is stopped, and after the liquid is absorbed by the non-aqueous electrolyte syringe 11, the non-aqueous electrolyte solution feeding part is operated to replenish the non-aqueous electrolyte solution. You may supply.

  Further, the temperature adjustment of the temperature adjustment heater 20 in the non-aqueous electrolyte tank 16 is adjusted by the temperature adjustment controller 18, and the non-aqueous electrolyte is applied to the electrode body 2 in the upper case 1 by the effect of reducing the viscosity of the non-aqueous electrolyte. The temperature of the nonaqueous electrolytic solution that is easily impregnated is adjusted to improve the impregnation property to the electrode body 2.

Here, the non-aqueous electrolyte injection part 7 moved to the liquid absorption stage A is lowered, and the injection pipe 14 is moved from the liquid level of the non-aqueous electrolyte in the supply nozzle 19 connected to the non-aqueous electrolyte storage tank 27. It is inserted deeply, and the injection position of the liquid injection tube 14 is set to be an insertion position that exceeds the amount of non-aqueous electrolyte to be absorbed once in the supply nozzle 19. The nonaqueous electrolyte solution is supplied to the nonaqueous electrolyte storage tank 27 faster than the speed at which the nonaqueous electrolyte solution is reduced when the nonaqueous electrolyte solution is absorbed into the nonaqueous electrolyte syringe 11.

  Next, the liquid injection piston 8 and the piston drive part 29 are connected. The detailed description of the piston drive unit 29 will be described later. The liquid injection piston 8 is positioned at the lower end of the non-aqueous electrolyte syringe 11, and the piston drive unit 29 is moved from the state where there is no space between the tip of the liquid injection piston 8 and the bottom of the non-aqueous electrolyte syringe 11. Operate to raise the injection piston 8. As a result, a predetermined nonaqueous electrolyte, which is the volume secured by the ascending stroke of the injection piston 8 through the injection pipe 14, is temporarily stored in the nonaqueous electrolyte syringe 11 with high accuracy and temporarily stored. After the inside of the syringe 11 is filled with the non-aqueous electrolyte, the non-aqueous electrolyte injection part 7 rises and moves to the original injection stage B.

  In the liquid injection stage B in which the nonaqueous electrolyte liquid injection part 7 moves and injects into the upper case 1 in which the electrode body 2 described in detail later is stored, the upper case 1 in which the electrode body 2 is stored on the base 4. The airtight chamber 10 of the nonaqueous electrolyte syringe 11 is connected, and the airtightness in the airtight chamber 10 is secured by the O-ring 15 fitted to the base 36. Further, a mechanism that can be chucked may be used to hold the upper case 1 on the case holder 37, and it may be held by a permanent magnet or vacuum suction. In the present invention, in order to simplify the structure, the case holder 37 is provided with a circular recess into which the upper case 1 can be fitted, and the case holder 37 is adapted to the type of the upper case 1 so that the manufacturing apparatus of the present invention can be used. Has versatility.

  Next, the piston driving unit 29 is coupled at the upper end of the liquid injection piston 8, and the pressure adjusting unit 26 connected to a vacuum pump (not shown) is connected to the non-aqueous electrolyte syringe 11. In addition, the piston drive unit 29 and the pressure adjustment unit 26 may be configured as the non-aqueous electrolyte solution injection unit 7 provided in the non-aqueous electrolyte syringe 11, and are individually configured in the embodiment of the present invention. The injection piston 8 passes through the center of the non-aqueous electrolyte syringe 11 and has a simple structure in which an O-ring 5 is fitted to the tip of the injection piston 8 so that the injection piston 8 slides up and down. The non-aqueous electrolyte syringe 11 is kept airtight.

  Next, after operating the vacuum pump to depressurize the airtight chamber 10 with the set pressure of the pressure adjusting unit 26, the vertical motion conversion type servo motor 21 in the piston driving unit 29 is operated. Here, since the drive stroke of the servo motor 21 is the same as the stroke of the liquid injection piston 8, high operation accuracy of the drive stroke of the servo motor 21 is essential. In the embodiment of the present invention, the rotation speed of the servo motor 21 is essential. Is converted to digital and the vertical movement of the liquid injection piston 8 is controlled with high accuracy by controlling the rotational speed, thereby adjusting the liquid absorption amount and liquid injection amount of the non-aqueous electrolyte.

  Furthermore, in the embodiment of the present invention, the servo motor 21 is used as the driving unit for the vertical movement of the liquid injection piston 8, but the driving unit using the rotary motion of the plate cam converted into the vertical movement or the driving unit using the air cylinder. The injection ston 8 can be driven up and down by a mechanical mechanism that combines a cam, ball screw, and servo motor, and a wide range of non-aqueous electrolyte amounts that are difficult to achieve by adjusting the stroke of the injection piston 8 alone. It is effective as a variable means to vary the amount of liquid absorption and injection, and it is not necessary to manufacture or replace a metering pump or injection mechanism in accordance with a predetermined amount of non-aqueous electrolyte. effective.

  Next, the piston driving unit 29 is operated to lower the liquid injection piston 8, so that the electrode body 2 housed in the upper case 1 from the liquid injection nozzle 6 is depressurized in the airtight chamber 10 and pressurized by the liquid injection piston 8. The non-aqueous electrolyte is supplied due to the pressure difference, and the injection piston 8 reaches the bottom dead center at the lower limit, and the supply of the non-aqueous electrolyte to the electrode body 2 ends.

  FIG. 2A is a state diagram of the start of injecting a non-aqueous electrolyte into the upper case 1 in which the electrode body 2 is accommodated. As shown in FIG. 2 (a), the non-aqueous electrolyte injected from the injection pipe 14 starts to be injected into the electrode body 2, and the non-aqueous electrolyte becomes spherical on the electrode body 2. As shown in 2 (b), the sphere expands as the amount of injected nonaqueous electrolyte increases, and grows on the electrode body 2 as a sphere larger than the outer shape of the electrode body 2. At this time, due to the surface tension of the nonaqueous electrolytic solution, the spherical shape is maintained without collapsing despite the state of protruding from the electrode body 2.

  Here, the outer dimension of the liquid injection guide ring 13 constituting the liquid injection nozzle 6 is configured to have a diameter larger than the outer dimension of the electrode body 2 and smaller than the inner diameter of the opening of the upper case 1. Since the space between the liquid injection guide ring 13 and the electrode body 2 of the upper case 1 is narrow, the larger spherical non-aqueous electrolyte comes into contact with the liquid injection guide ring 13, as shown in FIG. The non-aqueous electrolyte holding the spherical shape is broken by the surface tension. The non-aqueous electrolyte whose surface tension is once broken is attracted to the inner diameter portion of the injection guide ring 13, and the inner diameter portion of the injection guide ring 13 has a taper shape on the inner surface. Since the tip portion is located in the outer shape portion of the electrode body 2 and the inner diameter portion of the upper case 1, the nonaqueous electrolyte can be quickly poured into the gap between the outer shape portion of the electrode body 2 and the inner diameter portion of the upper case 1. Further, the tip end of the taper shape of the liquid injection guide ring 13 is sharply pointed, and is formed in a shape that does not cause non-aqueous electrolyte amount variation due to adhesion of the non-aqueous electrolyte solution.

  In this way, the non-aqueous electrolyte in a spherical shape is broken by the surface tension on the electrode body 2 so that the entire circumference of the electrode body 2 is covered with the non-aqueous electrolyte, and the pressure is reduced for a certain time. After maintaining the above, the decompression regulator 9 in the pressure adjusting unit 26 is operated to release the atmosphere over a certain period of time. Here, dry air is preferable as the supply air when the atmosphere is opened in a battery using a lithium material, and the airtight chamber 10 can be injected at atmospheric pressure without reducing the pressure.

  Furthermore, one, several, or several tens of these manufacturing apparatuses are arranged as a line, and each manufacturing apparatus injects a non-aqueous electrolyte into the upper case 1 in parallel to increase the processing capacity. Therefore, by using the base 4 as a jig for circulating, it becomes possible to take a line configuration with higher productivity. In addition to a structure in which one case 1 is held on one base 4, a structure in which a plurality of upper cases 1 are held on one large base 4 is also possible.

  As shown in FIG. 3, the upper case 1 that has been injected and impregnated is covered with the lower case 34 by covering the upper case 1, the side surface of the lower case 34 is reduced in diameter, and the opening of the lower case 34 is bent inward. Then, the flat battery 35 with high airtightness is formed.

  Here, the flat battery includes a coin-type primary battery, a coin-type secondary battery, and the like. Here, a coin-type lithium primary battery (hereinafter referred to as a coin-type battery), which is one of the flat batteries, is used. 3 is a cross-sectional view showing the overall structure of FIG. The coin-shaped battery 35 includes a pellet-shaped positive electrode body 30 constituting the electrode body 2, a pellet-shaped negative electrode body 31, and a separator 32 disposed between the positive electrode body 30 and the negative electrode body 31. An upper case 1 that houses a non-aqueous electrolyte (not shown) that moves lithium ions between the electrode body 2 and the electrode body 2, and an upper case that seals a space in which the electrode body 2 of the upper case 1 is housed. 1 comprises an insulating gasket 33 at the peripheral edge of the opening 1 and a lower case 34 that covers and seals the upper case 1. Further, a seal film (not shown) is formed at predetermined positions on the outer peripheral surface of the opening of the upper case 1, the inner peripheral surface of the insulating gasket 33, and the inner peripheral surface of the opening of the lower case 34. And exhibit higher airtightness.

Here, the positive electrode body 30 uses a lithium / cobalt acid compound, but is not limited thereto. For example, any one or more of a lithium composite oxide, a metal sulfide, a metal oxide, a metal selenium compound, and the like are mixed. It can also be used. In addition, the negative electrode body 31 is formed into a pellet by punching plate-like metallic lithium or lithium alloy serving as a negative electrode active material.

  Next, the separator 32 cuts off between the positive electrode body 30 and the negative electrode body 31, and allows lithium ions in the non-aqueous electrolyte to pass through while preventing a short circuit due to contact between both electrode materials. The separator 32 is a non-woven fabric formed of a fiber resin, and has a porosity of 10% to 50% and a thickness of 40 μm to 200 μm. Here, although polyphenylene sulfide is used, it is not limited to this, Polyethylene terephthalate, polyimide, polyamide, etc. are raised, and it is also possible to use any one or more.

  Examples of the non-aqueous electrolyte include EMC, lithium hexafluorophosphate, pentag lime, and tetraglyme, and any one or more of these are used.

  The lower case 34 is a container made of a conductive metal, and serves as an external positive electrode of the coin-type battery 35 by being in contact with the positive electrode body 30. Specifically, a metal container made of stainless steel is used for the lower case 34. However, the present invention is not limited to this. For example, a metal container in which a plurality of metals such as stainless steel, aluminum, and nickel are stacked. Etc. can also be used.

  The upper case 1 is a container made of a conductive metal that houses the electrode body 2, and becomes an external negative electrode of the coin-type battery 35 by being in contact with the negative electrode body 31. The upper case 1 may be a metal container in which a plurality of stainless steel and nickel metals are laminated.

  In addition, the insulating gasket 33 is formed in an annular shape, and is attached so as to be fitted into a gap generated between the lower case 34 and the upper case 1 when the lower case 34 and the upper case 1 are sealed. The gap is sealed. The insulating gasket 33 uses a polypropylene resin, but is not limited thereto, and a phenylene sulfite resin such as a polyether ketone resin, a polyether ether ketone resin, a polyethylene terephthalate resin, or a polyarylate resin is also used. Any one kind or a mixture of two or more kinds may be used.

  A sealing agent (not shown) is applied as a sealing film to the inner peripheral side surface of the lower case 34 and the inner peripheral side surface of the insulating gasket 33, and between the lower case 34 and the upper case 1 and the insulating gasket 33. The tightness of the internal space of the coin-type battery 35 is further enhanced by entering the generated minute gap. Specifically, a fluorine-based resin is used for the sealant, and the above-described fluorine-based resin is dissolved in the solvent for preparing the sealant. Specifically, cyclohexane or the like is used.

  Next, a method of manufacturing a flat battery and an apparatus for manufacturing the flat battery according to an embodiment of the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the nonaqueous electrolyte injection part 7 is moved to the liquid absorption stage A, and the injection pipe 14 at the tip of the nonaqueous electrolyte syringe 11 is connected to the supply nozzle 19 in the nonaqueous electrolyte tank 16. Insert 10mm deeper than the surface of the non-aqueous electrolyte. Next, the piston drive unit 29 is connected to the tip of the liquid injection piston 8. Next, the piston drive unit 29 is operated, and the liquid injection piston 8 located at the bottom dead center is pulled upward by a stroke of 10 mm in the time of 3 seconds, and the temperature adjustment controller 18 in the nonaqueous electrolyte tank 16 is used. 840 mg of non-aqueous electrolyte heated to about 40 ° C. by the temperature adjusting heater 20 whose temperature has been set is sucked into the non-aqueous electrolyte syringe 11 from the injection tube 14.

  Next, the non-aqueous electrolyte injection part 7 filled with the non-aqueous electrolyte in the non-aqueous electrolyte syringe 11 is moved to the injection stage B, and the upper case 1 in which the electrode body 2 is stored is placed on the base 4. After the holding, the airtight chamber 10 of the non-aqueous electrolyte injection unit 7 is connected to the base 4. In addition, the piston drive unit 29 is connected to the tip of the injection piston 8 of the nonaqueous electrolyte injection unit 7, and the pressure adjustment unit 26 is connected to the nonaqueous electrolyte syringe 11.

Next, while operating the vacuum pump and monitoring the pressure reducing pressure gauge 12 in the pressure adjusting unit 26, the pressure inside the airtight chamber 10 is reduced for 5 seconds at the set pressure 10 MPa of the pressure reducing regulator 9, and the piston driving unit 29 is operated. The liquid injection piston 8 was lowered and injected into the electrode body 2 accommodated in the upper case 1 in a time of 1 second.
After the injection, the pressure reduction is continued for 20 seconds, and then the vacuum pump is stopped and the pressure in the airtight chamber 10 is returned to 101.3 MPa which is the atmospheric pressure in 2 seconds. The upper case 1 taken out by opening the airtight chamber 10 was taken as Example 1.

(Comparative Example 1)
For comparison with the first embodiment of the present invention, the upper case 101 in which the electrode body 2 in which the same non-aqueous electrolyte as in the first embodiment is not injected into the apparatus configured as shown in FIG. After being supplied from a metering nozzle 112 connected to a non-aqueous electrolyte metering pump (not shown) in which 840 mg of non-aqueous electrolyte is separately installed in the temporary storage chamber 105, the pressure in the decompression chamber 104 is 10 kPa. The pressure is reduced for 5 seconds, the piston 103 is pushed down, the non-aqueous electrolyte is injected into the upper case 101 from the injection pipe 102 for 1 second, and after the injection is completed, the pressure is reduced for 20 seconds to reduce the pressure. The chamber 104 is returned to a pressure of 101.3 kPa, which is atmospheric pressure. Next, the decompression chamber 104 was opened, and the upper case 101 taken out was used as Comparative Example 1.

  In order to compare the weight of the loss non-aqueous electrolyte as a variation due to adhesion to the manufacturing apparatus or by evaporation during the injection of the same non-aqueous electrolyte in the above examples and comparative examples, each of the 20 upper cases The results of carrying out the following evaluation are shown in (Table 1).

  The variation in the weight of the non-aqueous electrolyte shown in Table 1 depends on the weight of the upper case where the non-aqueous electrolyte has been injected and the weight of the upper case where the non-aqueous electrolyte has not been injected. The difference between the reference weight of the liquid and the weight obtained by adding 840 mg was taken as the weight of the injected non-aqueous electrolyte, and the maximum value was compared with the difference between the minimum values.

  Further, the weight loss of the non-aqueous electrolyte is 840 mg of the reference weight of the non-aqueous electrolyte in addition to the weight of the upper case where the non-aqueous electrolyte is injected and the weight of the upper case where the non-aqueous electrolyte is not injected. The difference between the weight of the added nonaqueous electrolyte and the weight of the injected nonaqueous electrolyte was compared with the difference between the minimum weight of the nonaqueous electrolyte and the reference weight of the supplied nonaqueous electrolyte of 840 mg.

  Also, in order to compare the weight of the nonaqueous electrolyte impregnated in the electrode body within the same injection time as the impregnation weight of the nonaqueous electrolyte, inject the weight of the electrode body before injection and the nonaqueous electrolyte. Air blow was applied to the subsequent electrode body, and the difference from the weight of the electrode body after removing the non-aqueous electrolyte on the surface of the electrode body was compared.

（表１）より明らかなように実施例１による方法は、比較例１と比較して注液時における非水電解液のバラツキ重量も少なく精度が高い製造装置であり、上ケースに高精度な非水電解液の注液ができた。また、非水電解液の基準重量８４０ｍｇに対しても差が小さく、非水電解液の損失重量が少ないことから、非水電解液を精度良く吸い上げ製造装置内に残留なく注液できていることが言え、注液時の非水電解液の飛散や注液後に非水電解液の揮発の少ない製造装置であり、非水電解液の蒸発を抑制できたことで非水電解液の成分のバラツキを抑えることのできる方法である。また、非水電解液の含浸重量を見ても比較例１と実施例１では３０ｍｇもの差があり、非水電解液の温度を上げて粘度が下がり含浸し易くなり、注液ガイドリングによる非水電解液の表面張力を崩し、電極体の全面を覆うことや注液ガイドリングの内面のテーパ形状がさらに非水電解液の切れを良くしたと考えられ、同時間内で実施例１が含浸させるのに充分な機能を発揮していると言える。

As apparent from (Table 1), the method according to Example 1 is a highly accurate manufacturing apparatus with less variation weight of the non-aqueous electrolyte during injection compared to Comparative Example 1, and high accuracy in the upper case. A non-aqueous electrolyte was injected. Moreover, since the difference is small with respect to the reference weight 840 mg of the non-aqueous electrolyte, and the loss weight of the non-aqueous electrolyte is small, the non-aqueous electrolyte can be sucked up accurately and injected into the manufacturing apparatus without residue. However, it is a manufacturing device with less non-aqueous electrolyte volatilization after the injection and non-aqueous electrolyte volatilization after injection. It is a method that can suppress this. Moreover, even if it sees the impregnation weight of a non-aqueous electrolyte, there is a difference of 30 mg between Comparative Example 1 and Example 1, the temperature of the non-aqueous electrolyte increases, the viscosity decreases, and the impregnation becomes easier. It is considered that the surface tension of the aqueous electrolyte is broken, the entire surface of the electrode body is covered, and the tapered shape of the inner surface of the injection guide ring further improves the cutting of the non-aqueous electrolyte. It can be said that it is functioning enough to make it happen.

  Further, it should be noted that the maximum weight of the injected liquid of Comparative Example 1 is increased to 860 mg from the reference weight of 840 mg supplied with the nonaqueous electrolyte. This includes the variation in the amount of non-aqueous electrolyte supplied by the non-aqueous electrolyte constant supply pump, but more than that, the non-aqueous electrolyte remains in the device, and the remaining non-aqueous electrolyte is added. It is considered that the liquid was injected in excess of the weight of the supplied non-aqueous electrolyte. Further, in the comparative example, a variation in the weight of the 100 mg non-aqueous electrolyte occurs with respect to the injection amount of 840 mg, whereas in the manufacturing apparatus of the present invention, it can be suppressed to a very small amount of 5 mg. As described above, in the apparatus of the comparative example, the structure becomes smaller as the weight of the nonaqueous electrolyte to be injected becomes smaller, and further downsizing must be abandoned.

  There are factors that deteriorate the accuracy of liquid injection and the amount of non-aqueous electrolyte loss in the comparative example, and in the manufacturing apparatus according to comparative example 1, the non-aqueous electrolyte fixed amount supply pump is taken into account, and the temporary storage chamber, piston, It is considered that the nonaqueous electrolyte solution adhered and remained on the surface of the path of the water electrolyte solution, resulting in variations in the weight of the injected nonaqueous electrolyte solution. In addition, the surface tension of the non-aqueous electrolyte generated on the lower surface wetted surface of the injection nozzle during impregnation after injection impedes the force that the non-aqueous electrolyte impregnates the electrode body, and the non-aqueous electrolysis that impregnates the electrode body It is thought that the liquid weight was reduced.

  In addition, the nonaqueous electrolyte is likely to overflow on the electrode body so that it can be visually confirmed, and it is visually confirmed that the nonaqueous electrolyte leaks when the cover is covered with the lower case. did it. As a result, there are various troubles such as equipment contamination due to overflowing non-aqueous electrolyte and associated equipment operation troubles, coin-type battery surface contamination due to liquid spillage and quality troubles such as deterioration of battery characteristics due to lack of liquid. It has also been confirmed that this occurs.

  As described above, in Comparative Example 1, the deterioration of the accuracy of the injection that occurs when the injection is performed in a short time brings about a variation in the weight of the non-aqueous electrolyte, and as a result, the amount of the non-aqueous electrolyte is small. Causes shortage of the non-aqueous electrolyte in the coin-type battery, leading to a shortened battery life, and if there is a large amount of the non-aqueous electrolyte, there is a concern that the coin-type battery may swell due to gas generation and the safety may be reduced. . The present invention achieves stable battery life and safety by realizing liquid injection with high accuracy.

  According to the present invention, variation in the amount of non-aqueous electrolyte injected can be minimized, variation can be minimized, and non-aqueous electrolyte can be injected accurately. In addition, various troubles related to non-aqueous electrolyte spillage can be solved, and it has become possible to inject a minute amount of non-aqueous electrolyte, which has been difficult, with high accuracy in a reduced pressure or atmospheric condition. It is useful as a non-aqueous electrolyte method for producing a flat micro battery. Furthermore, since a large amount of non-aqueous electrolyte corresponding to the electrode body can be accommodated in the electrode body that accommodates as much as possible in the battery in order to increase the capacity, the load is high energy density. It is possible to produce a battery that has excellent characteristics and a long shelf life.

The schematic diagram of the manufacturing apparatus of the flat battery which shows the state of the liquid absorption stage which absorbs the nonaqueous electrolyte in embodiment of this invention, and the liquid injection stage which injects (A) State diagram of the start of liquid injection at the time of liquid injection in the embodiment of the present invention, (b) State diagram of a non-aqueous electrolyte that has become spherical due to surface tension at the time of liquid injection, (c) State diagram of the beginning of impregnation during injection Sectional drawing of the coin-type battery in one Embodiment of this invention Schematic diagram showing another conventional electrolyte solution injection device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Upper case 2 Electrode body 4 Base 5 O-ring 6 Injection nozzle 7 Non-aqueous electrolyte injection part 8 Injection piston 9 Decompression regulator 10 Airtight chamber 11 Non-aqueous electrolyte syringe 12 Decompression pressure gauge 13 Injection guide ring 14 Note Liquid pipe 15 O-ring 16 Non-aqueous electrolyte tank 17 Non-aqueous electrolyte supply pipe 18 Temperature adjustment controller 19 Supply nozzle 20 Temperature adjustment heater 21 Servo motor 25 Connecting shaft 26 Pressure adjustment section 27 Non-aqueous electrolyte storage tank 28 Non-aqueous electrolysis Liquid recovery layer 29 Piston drive unit 30 Positive electrode body 31 Negative electrode body 32 Separator 33 Insulating gasket 34 Lower case 35 Coin battery (flat battery)
36 Base 37 Case holder

Claims (9)

  A positive electrode material made of a positive electrode active material, a negative electrode material made of a material capable of holding lithium as an active material, and an electrode body formed by laminating a separator between them, and having an insulating gasket at the periphery of the opening A method for producing a flat battery in which a non-aqueous electrolyte is injected after being accommodated in a case and the opening of the upper case is sealed with a container-like lower case, wherein the upper case containing the electrode body is placed in an airtight chamber. The airtight chamber is depressurized and the nonaqueous electrolyte syringe absorbs itself from the nonaqueous electrolyte tank and injects the nonaqueous electrolyte stored in the nonaqueous electrolyte syringe. A method for producing a flat battery, comprising: breaking a nonaqueous electrolytic solution in a shape and impregnating the electrode body while covering the entire electrode body with the nonaqueous electrolytic solution.   The flat solution according to claim 1, wherein the nonaqueous electrolyte syringe is filled with a nonaqueous electrolyte solution so as not to contain air, and the nonaqueous electrolyte solution is injected and impregnated into an electrode body in the upper case. A manufacturing method of a battery.   The nonaqueous electrolyte solution is injected and impregnated into the electrode body in the case above the injection nozzle while adjusting the temperature of the nonaqueous electrolyte solution in the nonaqueous electrolyte tank. A method for producing a flat battery.   The non-aqueous electrolyte supplied to the non-aqueous electrolyte storage tank in the non-aqueous electrolyte tank is overflowed and recovered by the non-aqueous electrolyte recovery layer in the non-aqueous electrolyte tank. 2. The method for producing a flat battery according to claim 1, wherein the liquid surface of the aqueous electrolyte is sucked into the non-aqueous electrolyte syringe while being kept constant.   A positive electrode material stored in an upper case on the container, a negative electrode material, an electrode body laminated with a separator interposed therebetween, an airtight chamber for storing the upper case, a non-aqueous electrolyte tank equipped with a temperature adjustment unit, and temporarily A non-aqueous electrolyte syringe with a built-in injection piston for extruding the stored non-aqueous electrolyte, an injection nozzle connected to the non-aqueous electrolyte syringe comprising an injection tube and an injection guide ring, and the injection piston An apparatus for manufacturing a flat battery, comprising: a piston driving unit for operating the pressure sensor; and a pressure adjusting unit connected to the airtight chamber.   A non-aqueous electrolyte tank having a temperature adjustment heater and a temperature adjustment controller as a temperature adjustment unit, a non-aqueous electrolyte storage tank, a non-aqueous electrolyte recovery tank, and a non-aqueous electrolyte solution in the non-aqueous electrolyte tank 6. The flat battery manufacturing apparatus according to claim 5, comprising a supply nozzle communicating with the non-aqueous electrolyte storage tank in which the syringe absorbs the non-aqueous electrolyte.   The outer dimension of the liquid injection guide ring is configured within the range from the outer dimension of the electrode body housed in the upper case to the inner diameter dimension of the upper case, and the inner surface of the tip of the liquid injection guide ring has a tapered shape. The flat battery manufacturing apparatus according to claim 5.   6. The flat battery manufacturing apparatus according to claim 5, wherein the non-aqueous electrolyte syringe has variable means for varying the amount of liquid absorbed and the amount of liquid injected. A nonaqueous electrolyte solution that overflows the nonaqueous electrolyte solution in the nonaqueous electrolyte solution tank and keeps the liquid level of the nonaqueous electrolyte solution constant and communicates with the nonaqueous electrolyte solution storage tank. 6. The flat battery manufacturing apparatus according to claim 5, wherein the non-aqueous electrolyte is supplied to the non-aqueous electrolyte syringe through a supply nozzle in which the liquid level is always kept constant. .

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