JP5206186B2 - Inspection system for inspecting materials for active materials for secondary batteries - Google Patents

Description

  The present invention relates to an inspection system for inspecting a material of an active material for a secondary battery.

The active material for a lithium ion secondary battery is usually produced through a plurality of steps such as coprecipitation, pressing, filtration, mixing, pulverization, drying, stirring, addition, firing, and particle size adjustment. Each step is either a batch or continuous process. A defective product may be generated in such a process, and it is necessary to inspect it. As a method for inspecting an active material for a secondary battery, a method of inspecting whether or not it is appropriate by measuring and evaluating PH by mixing lithium manganese complex oxide, which is an active material for a secondary battery, with an oxidizing aqueous solution (Patent Document 1).
JP 2005-326191 A

  However, in Patent Document 1, since an inspection is performed by mixing a lithium manganese complex oxide in an oxidizing aqueous solution, it cannot be used as an active material for a lithium ion secondary battery after the inspection.

  Therefore, an object of the present invention is to provide a non-destructive inspection system, and to provide a secondary battery active material inspection system that can be used as a secondary battery active material even after the inspection. It is.

An inspection system for inspecting a material of an active material for a secondary battery according to the present invention for solving the above problems is characterized by the following configuration. A vibration means for vibrating the material of the active material for a secondary battery Ru is high density, irradiating means for irradiating light to the densified material, the light emitted by said irradiation means, said high-density A light receiving means for receiving reflected light or transmitted light emitted from the converted material and outputting a signal based on the received light; a calculating means for calculating a color value from the signal; and a color calculated by the calculating means Value is compared with a color value calculated by a good product in advance, and whether the calculated color value is a value within a specified range based on the color value by the good product, Determining means for determining whether the material is non-defective.

  According to the present invention, since the pretreatment for densifying the material of the active material for the secondary battery can be performed, and the inspection can be performed by the color value obtained by irradiating the pretreatment, the material of the active material for the secondary battery Is not wasted.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments to which the invention is applied will be described with reference to the accompanying drawings. However, the inspection system of the present invention is not limited to the following embodiments. In the accompanying drawings, each component is exaggerated for clarity of explanation. In the drawings, the same elements are denoted by the same reference numerals, and the description of the same elements is omitted in the specification.

(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of an inspection system for an active material for a secondary battery in the first embodiment of the present invention. FIG. 2A is a plan view of the inspection system shown in FIG. 2B to 2D are plan views of the inspection system having a different arrangement from that in FIG. 2A. That is, it shows the difference in the means for densifying the material of the active material for the secondary battery, the difference in the irradiation route at the time of irradiation, and the difference in whether reflected light or transmitted light is received as the secondary light. Here, it demonstrates mainly using FIG. 2A.

  As shown in FIG. 1, the secondary battery active material inspection system of the present embodiment includes a hopper 1, a hopper discharge port 2, a measurement tube 3, a discharge valve 4, a pressing guide 5, an incident window 6, an observation window 7, A cylindrical lower portion 8, an outlet tube 9, a light source 10, a spectroscope 11, an imaging device 12, a measurement chamber 13, a defective product recovery valve 14, a defective product recovery tray 15, and an external computer 19 are provided. For example, the image sensor 12 is a color CCD image sensor 12, and the external electronic computer 19 is a personal computer.

  The hopper 1 is connected to the measurement pipe 3 via the hopper discharge port 2. At the lower part of the measurement pipe 3, the outlet pipe 9 and the defective product collection tray 15 are respectively connected via the discharge valve 4 and the defective product collection valve 14. Are connected to each other, and these function as conveying means. The transport means is used in a series of processes from the step of increasing the density by compressing the material of the active material for the secondary battery to the end of the inspection after the step of determining whether or not it is a non-defective product. Convey material material. The material of the secondary battery active material is put into the hopper 1 by an inspector. The hopper discharge port 2 may have a valve function between the measurement tube 3. The operation of the discharge valve 4 and the defective product recovery valve 14 is performed by an inspector. The charging of the active material for the secondary battery and the operation of the valve may be automatically controlled by another system.

  After completion of the inspection, the conveying means also has a function of separating non-defective products or defective products into different systems as shown in FIG. In the process after the inspection is completed, first, the discharge valve 4 is opened, and then the material of the active material for the secondary battery is closed through the outlet pipe 9 if it is a non-defective product, and then the discharge valve 4 is transported to the next process. The valve 4 is opened and conveyed to the defective product collection tray 15.

  The pressing guide 5, the incident window 6, and the observation window 7 are installed in the measuring tube 3, and function as a densification means by compressing the material of the active material for the secondary battery. The pressing guide 5 is fixed between the measurements 3 and functions as a guide in which the entrance window 6 is movable. The incident window 6 has a convex shape and functions as a compression means for pressing the material of the active material for the secondary battery in the measurement tube 3 along the pressing guide. The incident window 6 is preferably transparent in order to make light incident from a light source 10 described later and irradiate the material of the active material for the secondary battery. The observation window 7 may be fixed to the measurement tube 3. Similarly to the incident window 6, the observation window 7 is preferably transparent in order to transmit secondary light from the material of the active material for the secondary battery.

  The positions where the pressing guide 5, the entrance window 6, and the observation window 7 are installed in the measurement tube 3 differ depending on whether reflected light is used as secondary light or transmitted light is used. As shown in FIG. 2A, when reflected light is used as the secondary light, the incident window 6 and the observation window 7 can be installed at an arbitrary angle that is not a straight line. When transmitted light is used as the secondary light, as shown in FIG. 2B, the pressing guide 5a, the incident window 6a, and the observation window 7a can be installed on a straight line. As shown in FIG. 2C, when the reflected light is used as the secondary light, the light source 10 and the color CCD image sensor 12 can be installed on the observation window 7b side. In this case, since the entrance window 6b has only the compression function of the entrance window of FIGS. 2A and 2B, it does not have to be a transparent material. Furthermore, as shown in FIG. 2D, when the reflected light is used as the secondary light and the light source 10 and the color CCD image sensor 12 are installed on the observation window 7c side, the pressing guide 5c is installed on the measuring tube 3 and has a convex shape. The density may be increased by pressing the observation window 7c along the pressing guide 5c and compressing the material of the active material for the secondary battery. As described above, various installations can be appropriately set according to the space of the equipment.

  The densification means closes the discharge valve 4 and presses the incident window 6 along the pressing guide 5 while the measuring tube 3 is sufficiently filled up to the hopper discharge port 2 with the material of the secondary battery active material. Densify. The densification means densifies the material of the active material for the secondary battery by compacting and smoothing the material of the active material for the secondary battery. This measure increases the reproducibility of the color measurement. In addition, even if light is applied to the secondary battery active material by the irradiation means described later without increasing the density by compacting and smoothing, the secondary battery active material from the secondary battery active material is not received by the light receiving means. It was difficult to calculate the color value from the information of the secondary light by the calculation means without sufficiently receiving the secondary light.

  The densification means may be densified by compressing it with another compression device, a compacting jig, or a material for an active material for a secondary battery in a measuring tube, and observing it in an observation window or a compact receiver. .

Although depending on the material type of the active material for the secondary battery, the color measurement can be performed with high accuracy and reproducibility by setting the density to, for example, 1 to 5 g / cm ³ by the densification means.

  When the material of the secondary battery active material is compressed and densified by the densification means, it is preferable to form a pellet with a thickness of about 10 mm or less and an applied pressure of 1 to 1000 MPa. In the present embodiment, when glass made of the entrance window 6 and the observation window 7 are used, the pressure applied when compressing and densifying the material of the active material for the secondary battery is 1 to 1, considering the device strength. It is preferable to set to 100 MPa. In addition to this value, in order to perform color measurement with high accuracy and reproducibility, the applied pressure can be appropriately set in consideration of the entire system apparatus.

  The light source 10 functions as an irradiation unit. An irradiation means irradiates light to the material of the active material for secondary batteries. The light intensity and wavelength by the irradiating means can be arbitrary, but it is preferable to use one that is suitable for the light receiving means or the calculating means.

  The irradiating means may irradiate light in a specific wavelength region by providing a spectroscope upstream of the material of the secondary battery active material using, for example, a commercially available light. Here, the wavelength of the irradiation means is preferably 200 to 900 nm, and more preferably 300 to 800 nm. By using light of 300 to 800 nm, a commercially available color CCD image sensor can be used as a light receiving means described later, which is advantageous in terms of cost.

  The color CCD image sensor 12 functions as a light receiving means for photographing the secondary battery active material through the observation window 7. The light receiving means receives secondary light emitted from the material of the secondary battery active material. Secondary light is light in which light (primary light) irradiated from the irradiation means is reflected, refracted or transmitted by the material of the active material for the secondary battery, and indicates reflected light, refracted light or transmitted light.

  Whether the material of the active material for the secondary battery that has been compacted and smoothed, the irradiation means, and the light receiving means are installed in a position where the transmitted light is collected as the secondary light or the color is collected by the reflected light Can be selected as appropriate. Preferably, the reflected light is received from the viewpoint of reproducibility.

  The color CCD image sensor 12 is composed of a plurality of pixels, and an output signal is position information of each pixel and color information such as RGB and CMY of the pixel. Such information is sent to an external electronic computer 19 connected by a known wired or wireless method. Based on such information, the external electronic computer 19 calculates information by secondary light from the material of the secondary battery active material as a color value.

  The light receiving unit needs to include a light receiving element having sensitivity in a wavelength region that can cover the wavelength region of light from the irradiation unit or the spectroscope after the irradiation unit. If the irradiating means irradiates light of 200 to 900 nm, it is preferable that the light receiving means also has sensitivity in the wavelength region of 200 to 900 nm.

  An external electronic computer (such as a personal computer (PC)) 19 functions as a calculation unit that calculates a color value based on information of photographing data photographed by the color CCD image sensor. Specifically, it is a calculation program system incorporated in the external electronic computer 19, and calculates information by the secondary light from the material of the active material for the secondary battery output from the color CCD image sensor as the color value. It is.

  The color value is expressed as a color system such as an RGB color system or an XYZ color system. The color value preferably includes all of the hue value, the lightness value, and the chroma value. For example, the color value may be digitized into L * a * b * color system color coordinates that are a color space defined by JIS Z 8729. preferable.

  The measurement chamber 13 has a function for eliminating the influence of an external light source during color measurement. In the measurement chamber 13, a pressing guide 5, an incident window 6, an observation window 7, a cylindrical lower part 8, a light source 10, a spectroscope 11, and a color CCD image sensor 12 are provided. However, a part or all of the measuring tube 3, a part or all of the cylindrical lower part 8, and the discharge valve 4 may not be provided in the measuring chamber 13.

  By providing the irradiating means and the light receiving means in the measurement chamber in which the external light is blocked, the influence of the external light can be reduced, and the color measurement of the material of the active material for the secondary battery can be performed with high accuracy and reproducibility. .

  The external electronic computer (such as a personal computer (PC)) 19 further functions as a determination unit that determines whether the material of the secondary battery active material to be inspected is a non-defective product based on the calculated color value. Specifically, the determination program system is incorporated in the external electronic computer 19. The external electronic computer 19 has a calculation program system and a determination program system. However, the external electronic computer 19 may be incorporated in different external electronic computers 19, and in this case, they may be interconnected by wireless or wired communication. good.

  The determination program system of the external electronic computer 19 includes a color value based on secondary light information emitted by the material of the secondary battery active material calculated by the calculation program system, and a good secondary battery active material obtained in advance. It is determined whether or not it is a non-defective product by comparing the color value of the material.

  The determination criteria for the non-defective product by the determining means are performed using a database of non-defective products and defective products based on the correlation between the color value and the battery characteristic evaluation that are built in advance. Battery characteristic evaluation is evaluation of the performance as a secondary battery, and the performance of the secondary battery generally includes output, density, life, stability, use environment, charge / discharge rate, cost, and the like.

  Specifically, depending on whether the L value, a value, and b value, which are the color values of the L * a * b * color system outputted from the calculation means, are within a prescribed range of non-defective products. Judge whether it is a non-defective product.

  Each of these components is connected by a transport unit and may be provided as a part of the transport unit. Further, the irradiation unit, the light receiving unit, and / or the calculating unit may be provided in one apparatus. For example, a light source may be attached to a color CCD image camera, and an RGB value or a Lab value may be output as an output signal by incorporating a calculation program in advance. Each of these components may be connected by wired or wireless mutual communication means in order to be controlled and managed by the inspection system. Further, the inspector may transport the material of the active material for the secondary battery to each component without using the transport means. Control and management of each component may also be assisted by another system or inspector.

  In the inspection system for the active material for the secondary battery according to the present embodiment configured as described above, a non-defective product or a defective product is used as the active material for the secondary battery based on the color measurement value obtained by photographing with the color CCD image sensor 12. It is determined whether there is any.

  A specific inspection processing procedure will be described in detail.

  FIG. 3 is a flowchart showing an inspection process of the inspection system for the active material for the secondary battery shown in FIGS. As described above, in the secondary battery active material inspection system according to the present embodiment, whether the active material for the secondary battery is a non-defective product or a defective product based on the color measurement values obtained by the color CCD image sensor 12. Is determined.

  As shown in FIGS. 1 and 2, in the secondary battery active material inspection system of the present embodiment, first, the discharge valve 4 is closed (S101). In the present embodiment, by closing the discharge valve 4, the material of the active material for the secondary battery does not flow below the discharge valve 4.

  Next, the material of the secondary battery active material is supplied to the hopper 1 (S102). The supplied material of the active material for the secondary battery stays in the measuring tube 3 through the hopper discharge port 2. Depending on the supply amount, the active material for the secondary battery that stays in the measuring tube 3 gradually increases, and is placed above the pressing guide 5, the incident window 6, and the observation window 7. While the secondary battery active material is below the hopper discharge port 2, the supply of the secondary battery active material is stopped (S103). That is, at this time, the space between the hopper discharge port 2 and the discharge valve 4 in the measurement tube 3 is filled with the active material for the secondary battery.

  The active material for the secondary battery existing in a part of the measuring tube 3 by the entrance window 6 and the observation window 7 is compacted and smoothed to increase the density (S104). Step S104 is a stage in which the material of the secondary battery active material is compressed to increase the density. The compaction here is almost synonymous with densification, and this operation increases the reproducibility of the color measurement.

  Color measurement is performed by photographing the active material for the secondary battery compacted in step S104 with the color CCD image sensor 12 (S105). Step S105 is a step of irradiating light on the material of the active material for the secondary battery that has been densified, and a step of receiving reflected light or transmitted light emitted from the material by the irradiated light. The photographing data photographed by the color CCD image sensor may be any of reflection, transmission and refraction by the active material for the secondary battery of the light source 10, but is preferably reflection. Whether it is reflection, transmission, or refraction is determined by the positional relationship among the measurement tube 3, the pressing guide 5, the entrance window 6, the observation window 7, the light source 10, the spectroscope 11, and the color CCD image sensor 12. The analysis of the color measurement result from the obtained photographing data is preferably performed by an external computer connected by a known wired or wireless method from the viewpoint of the certainty of the analysis (S106). Step S106 is a step of calculating a color value from the received light. It is determined whether the active material for the secondary battery is a non-defective product or a defective product from the database of non-defective products and defective products based on the correlation between the color measurement result and the battery characteristic evaluation that is built in advance (S107). In step S107, the calculated color value is collated with a pre-calculated color value by a good product, and depending on whether or not the calculated color value is within a specified range based on the color value by the good product, for the secondary battery. This is a step of determining whether or not the material of the active material is a non-defective product.

  When it is determined that the secondary battery active material is a non-defective product (S108: YES), the defective product recovery valve 14 is closed to prevent the secondary battery active material from entering the defective product recovery tray 15 (S109). Further, the discharge valve 4 is opened, and the secondary battery active material staying in the measuring tube 3 flows to the next step through the branch pipe in the figure (S110). At that time, a part of the active material for the secondary battery may be deformed into a pellet shape by the compacting operation, but it is easily crushed by the kneading operation, which is an essential step in electrode production.

  When the active material for the secondary battery is determined to be defective (S111: NO), the defective product recovery valve 14 is opened (S112). Further, when the discharge valve 4 is opened, the active material for the secondary battery is recovered in the defective product recovery tray 15 (S113).

  The material of the secondary battery active material to be inspected in the inspection system having the above configuration will be described.

  The material of the active material for the secondary battery includes the active material for the secondary battery constituting the positive electrode and the negative electrode for manufacturing the secondary battery, and the active material for the secondary battery generated in the process of manufacturing the active material. It is an intermediate. That is, the material of the secondary battery active material includes a compound or a mixture that omits the starting material generated in the step of manufacturing the final form of the secondary battery active material and the final form of the secondary battery active material. The active material intermediate for secondary batteries is shown.

  The secondary battery active material intermediate is a compound or mixture excluding the starting material produced in the process of producing the secondary battery active material, and is known mixing, crushing, firing, drying, stirring, crushing , Spraying, precipitation, filtration, hydrothermal, dispersion, granulation, centrifugation, washing with water, evaporation, classification, magnetic separation, aging, and the like. Examples of the form of the secondary battery active material intermediate include gas, liquid, sol, gel, solid, and powder.

  When compressed and densified by the densification means, the active material for secondary battery and the active material intermediate for secondary battery are preferably powder, and the particle size thereof is 0.1 to 100 μm. It is preferable. Especially preferably, it is 1-50 micrometers. The particle size referred to here indicates the particle size of the secondary particles. Furthermore, the average particle size of the active material for secondary battery and the active material intermediate for secondary battery is preferably 1 to 20 μm, particularly preferably 2 to 10 μm. Here, the particle size of the secondary particles can be measured by a known laser diffraction / scattering particle size distribution analyzer.

Examples of the active material for a secondary battery include a positive electrode active material for a secondary battery whose composition formula can be expressed as Li _w Ni _x Mn _y Co _z O _{2 + δ} . However, 1.1 <w <1.5, 0.1 <x <0.4, 0.4 <y <0.9, 0 <z <0.2, w + x + y + z = 2, −0.2 <δ <0.2. This is used for a lithium ion secondary battery of a non-aqueous electrolyte secondary battery.

  As preferable conditions for the lithium ion secondary battery, L * a * b * color system color coordinates which are color spaces defined by JIS Z 8729 are 0 <a <10, −1.2 <b <20. Those satisfying 0, 0 <L <30 are preferable. Among the lithium metal elements added excessively with respect to the sum of the molar ratios of the transition metal elements by simultaneously satisfying the L * a * b * color system color coordinates and the composition formula, the lithium metal site Since the excess that does not fit into the transition metal element site in the crystal structure penetrates into the transition metal element site without excess and deficiency, and the average valence of Mn approaches from tetravalent to trivalent, the nonaqueous electrolyte 2 exhibiting a higher discharge capacity. An inspection system for a positive electrode active material for a secondary battery can be provided. The a, b, and L values in the L * a * b * color system color coordinates are preferably 0 <a <10, −1.2 <b <20.0, and 0 <L <30. More preferably, 1.6 <a <8, −1.2 <b <10.0, 10 <L <25, and most preferably 3 <a <6, 2.0 <b <5.0, 15 <L <23. When the measurement result that satisfies the above range condition is obtained by inspection, the active material for the secondary battery is determined as a non-defective product.

  Here, as a synthesis method for obtaining the positive electrode active material for a non-aqueous electrolyte secondary battery, various known methods such as a solid phase method, spray drying, and coprecipitation method may be selected.

  The firing temperature for obtaining the positive electrode active material for a non-aqueous electrolyte secondary battery of the present invention is preferably 700 ° C. or higher and lower than 1000 ° C., more preferably 750 ° C. or higher and lower than 950 ° C. When the firing temperature is less than 700 ° C., the reaction for obtaining the positive electrode active material for a non-aqueous electrolyte secondary battery does not proceed, or it takes an enormous reaction time that is industrially impractical. In addition, when the firing temperature is 1000 ° C. or higher, the reaction proceeds rapidly, it becomes difficult to control the valence of the transition metal element, and some of the compounds essential for the reaction contained in the precursor may volatilize. Therefore, it is difficult to obtain the target positive electrode active material for a nonaqueous electrolyte secondary battery, which is not preferable. A plurality of firing steps may be included in all the steps for obtaining the positive electrode active material for a non-aqueous electrolyte secondary battery of the present invention. In addition, said baking temperature shows the conditions of what is called main baking, and it is not this limitation about temporary baking.

  According to this embodiment, the following effects are produced.

  The material of the active material for the secondary battery is supplied to the inspection system of this embodiment, compressed by the incident window 6 and the observation window 7 to be densified, photographed by the color CCD image sensor 12, and data Non-defective / defective products can be determined by measuring and analyzing the color. Furthermore, according to this embodiment, it is also possible to inspect the firing conditions, pulverization conditions, mixing degree, particle size adjustment conditions, and composition of the active material intermediate for a secondary battery for each step. Therefore, a simple inspection system that can irradiate a substance with light and inspect it by the color of the secondary light from the substance by applying a pretreatment that compresses and densifies the material of the active material for the secondary battery. Can provide. Further, a part of the material of the secondary battery active material may be deformed into a pellet shape by compression, but can be easily crushed by a kneading operation. Therefore, it is possible to provide a non-destructive inspection system that does not waste the material of the active material for the secondary battery. In addition, there is no concern about industrial waste and the cost can be reduced.

(Second Embodiment)
FIG. 4 is a diagram showing a schematic configuration of an inspection system for an active material for a secondary battery in the second embodiment of the present invention.

  In the present embodiment, a spectrophotometer 18 is used instead of the light source and the color CCD image sensor of the first embodiment.

  As shown in FIG. 4, the active material inspection system for a secondary battery according to this embodiment includes a hopper 1, a hopper discharge port 2, a measurement tube 3, a discharge valve 4, a pressing guide 5, an observation window 16, and a green compact receiver 17. , A cylindrical lower part 8, an outlet pipe 9, a measurement chamber 13, a defective product collection valve 14, a defective product collection tray 15, a spectrophotometric measurement probe 18, and an external electronic computer 19. Except for the spectrophotometer 18, the description is omitted because it is the same as that of the first embodiment.

  The spectrophotometric probe 18 functions as an irradiating unit that irradiates the material of the active material for the secondary battery and a light receiving unit that receives reflected light emitted from the irradiating unit. A color measurement result is transmitted from the spectrophotometric probe 18 to the external electronic computer 19.

  In the secondary battery active material inspection system of the present embodiment configured as described above, it is determined by the spectrophotometer whether the secondary battery active material is a non-defective product or a defective product.

  As described above, the described embodiment has the following effects.

  The secondary battery active material is supplied to the inspection system of the present embodiment, compressed by the observation window 16 and the green compact receiver 17, measured by the spectrophotometric probe 18, and colored by an external computer 19. By obtaining, it is possible to determine a non-defective product or a defective product. Further, compared to the first embodiment, the configuration is simple because a spectrophotometer having both an irradiation means and a light receiving means is used, and the measuring instrument that specializes in analyzing light is highly accurate. Measurement is possible.

  Furthermore, according to this embodiment, it is also possible to inspect indirectly the firing conditions, pulverization conditions, mixing degree, particle size adjustment conditions, and composition of the secondary battery active material intermediate.

  In the inspection system for an active material for a secondary battery of the present embodiment, the same processing as the flowchart of the first embodiment shown in FIG.

(Third embodiment)
FIG. 5 is a diagram showing a schematic configuration of an inspection system for an active material for a secondary battery in the third embodiment of the present invention.

  In the present embodiment, a photoelectric colorimeter 20 is used instead of the light source, the color CCD image sensor, and the external electronic calculator 19 of the first embodiment.

  As shown in FIG. 5, the secondary battery active material inspection system according to the present embodiment includes a hopper 1, a hopper discharge port 2, a measurement tube 3, a discharge valve 4, a pressing guide 5, an observation window 16, and a green compact receiver 17. , A cylindrical lower part 8, an outlet pipe 9, a measurement chamber 13, a defective product collection valve 14, a defective product collection tray 15, and a photoelectric colorimeter 20. Since the other than the photoelectric colorimeter 20 is the same as that of the first embodiment, the description thereof is omitted.

  The photoelectric colorimeter 20 is an irradiation means for irradiating the material of the active material for the secondary battery with light, a light receiving means for receiving the reflected light emitted therefrom from the observation window 16, and a calculation means for calculating a color value from the reflected light. And a determination means for determining whether the product is non-defective based on the calculated result.

  In the secondary battery active material inspection system of the present embodiment configured as described above, it is determined whether the active material for the secondary battery is a non-defective product or a defective product by the photoelectric colorimeter.

  As described above, the described embodiment has the following effects.

  By supplying the active material for the secondary battery to the inspection system of the present embodiment, compressing it with the observation window 16 and the compact receiver 17, and measuring and analyzing with the photoelectric colorimeter 20 to obtain the color Good products and defective products can be determined. Further, compared to the first and second embodiments, a more detailed color value can be measured by using the photoelectric colorimeter 20, and a simple and low-cost measurement can be performed by a configuration that does not use an external electronic device.

  Furthermore, according to this embodiment, it is also possible to inspect indirectly the firing conditions, pulverization conditions, mixing degree, particle size adjustment conditions, and composition of the secondary battery active material intermediate.

  In the inspection system for an active material for a secondary battery of the present embodiment, the same processing as the flowchart of the first embodiment shown in FIG.

(Fourth embodiment)
FIG. 6 is a diagram showing a schematic configuration of a secondary battery active material inspection system according to the fourth embodiment of the present invention.

  As shown in FIG. 6, the secondary battery active material inspection system according to this embodiment includes a hopper 1, a hopper discharge port 2, a measurement tube 3, a measurement chamber 13, a photoelectric colorimeter 20, a dust jig 21, and a dust compact. A jig 22, a green compact 23, an observation window 24, a non-defective product collecting valve 25, a defective product collecting valve 26, and a defective product collecting tray 27 are provided.

  An observation window 24 and a photoelectric colorimeter 20 are provided in the measurement chamber 13. However, a part or all of the measurement tube 3 may not be in the measurement chamber 13. The measurement chamber 13 has a function of eliminating the influence of an external light source at the time of color measurement. The compacting jig 21 and the compacting jig 22 constitute a part of the measuring tube 3 and have a function of compacting an active material for a secondary battery that circulates in the measuring tube 3. The hopper discharge port 2 may have a valve function. The photoelectric colorimeter 20 measures the color of the active material for the secondary battery through the observation window 24. By providing the measuring tube 3 with an inclination, the active material for the secondary battery in the tube is circulated from upstream to downstream. Further, instead of the photoelectric colorimeter 20, the light source + color CCD image sensor + external electronic computer used in the first embodiment and the spectrophotometer + external electronic computer used in the second embodiment may be used.

  In the secondary battery active material inspection system of the present embodiment configured as described above, it is determined whether the active material for the secondary battery is a non-defective product or a defective product by the photoelectric colorimeter. Hereinafter, the inspection system for the secondary battery active material according to the present embodiment will be described with reference to FIG.

  FIG. 7 is a flowchart showing an inspection process of the secondary battery active material inspection system shown in FIG. As described above, in the secondary battery active material inspection system according to the present embodiment, the photoelectric color meter 20 performs measurement and color analysis to determine whether the secondary battery active material is a non-defective product or a defective product. The

  As shown in FIG. 7, in the secondary battery active material inspection system of this embodiment, first, the defective product recovery valve 26 is closed (S401), and then the non-defective product recovery valve 25 is opened (S402).

  Next, an active material for a secondary battery is supplied to the hopper 1 (S403). The supplied secondary battery active material flows through the hopper discharge port 2 into the measuring tube 3. In the present embodiment, the non-defective product recovery valve 25 is opened and the defective product recovery valve 26 is closed, whereby the active material for the secondary battery passes through the non-defective product recovery valve 25 without stagnation. By adjusting the speed at which the active material for the secondary battery is supplied to the hopper 1 or the opening of the valve in the hopper discharge port 2, the active material for the secondary battery is adjusted to the measuring tube 3. The speed which distributes inside can be adjusted.

  In a state where the active material for the secondary battery is circulating in the measuring tube 3, the active material for the secondary battery existing in a part of the measuring tube 3 is removed by the compacting jig 21 and the compacting jig 22. Compressed powder, smoothed and densified (S404). Step S404 is a stage where the material of the secondary battery active material is compressed to increase the density. The compaction here is almost synonymous with densification, and this operation increases the reproducibility of the color measurement.

  At the time when the active material for the secondary battery compacted in step S404 circulates in the measuring tube 3 and enters the measurement range of the photoelectric colorimeter 20, the color measurement is performed (S405). Step S405 is a step of irradiating the densified secondary battery active material with light and receiving reflected or transmitted light emitted from the material by the irradiated light. The analysis of the color measurement result from the obtained measurement data is also performed by the photoelectric colorimeter 20 (S406). Step S406 is a step of calculating a color value from the received light. It is determined whether the active material for the secondary battery is a non-defective product or a defective product from a database of non-defective products and defective products based on the correlation between the color measurement result and the battery characteristic evaluation that are built in advance (S407). In step S407, the calculated color value is compared with the color value calculated in advance by the good product, and depending on whether or not the calculated color value is within a specified range based on the color value by the good product, for the secondary battery. This is a step of determining whether or not the material of the active material is a non-defective product.

  When it is determined that the active material for the secondary battery is a non-defective product (S408: YES), the non-defective product recovery valve 25 remains open (S409), and the defective product recovery valve 26 is also kept closed (S410). ). That is, the circulation of the active material for the secondary battery in the measuring tube 3 is maintained and does not stop. At that time, a part of the active material for the secondary battery may be deformed into a pellet shape by the compacting operation, but it is easily crushed by the kneading operation, which is an essential step in electrode production.

  If the active material for the secondary battery is determined to be defective (S411: NO), the non-defective product recovery valve 25 is closed (S412), and the defective product recovery valve 26 is opened (S413). That is, the active material for the secondary battery is collected in the defective product collection tray 27 and is distinguished from the non-defective product.

  These series of operations are continuously performed, and the active material for the secondary battery determined to be a non-defective product flows to the next process.

  As described above, the described embodiment has the following effects.

  The secondary battery active material is supplied to the inspection system of the present embodiment, compressed by the compacting jig 21 and the compacting jig 22, and measured and analyzed by the photoelectric colorimeter 20 to obtain the color. As a result, a non-defective product or a defective product can be determined. Moreover, in addition to the effect of 3rd Embodiment, the active material for secondary batteries can be determined continuously.

  Furthermore, according to this embodiment, it is also possible to inspect indirectly the firing conditions, pulverization conditions, mixing degree, particle size adjustment conditions, and composition of the secondary battery active material intermediate.

(Fifth embodiment)
FIG. 8 is a diagram showing a schematic configuration of a secondary battery active material inspection system according to the fifth embodiment of the present invention.

  As shown in FIG. 8, the secondary battery active material inspection system of the present embodiment includes a photoelectric colorimeter 20, a belt conveyor 28, an active material holding plate 29, a secondary battery active material 30, a dust jig 31, A measurement chamber 32; The light source + color CCD image sensor + external computer used in the first embodiment and the spectrophotometer + external computer used in the second embodiment may be used in place of the photoelectric colorimeter 20.

  FIG. 9 is a flowchart showing the inspection process of the secondary battery active material inspection system shown in FIG. As described above, in the secondary battery active material inspection system according to the present embodiment, the photoelectric color meter 20 performs measurement and color analysis to determine whether the secondary battery active material is a non-defective product or a defective product. The

  As shown in FIG. 9, in the secondary battery active material inspection system of the present embodiment, first, the conveyor 28 is operated (S501), and the secondary battery active material is supplied to the right in FIG. The active material for the secondary battery is moved to (S502).

  The active material for the secondary battery is compacted, smoothed and densified by the compacting jig 31 (S503). Step S503 is a stage in which the material of the active material for the secondary battery is compressed to increase the density. The compaction here is almost synonymous with densification, and this operation increases the reproducibility of the color measurement.

  Measurement is performed when the secondary battery active material compacted in step S503 moves on the conveyor 28 and enters the measurement range of the photoelectric colorimeter 20 (S504). Step S504 is a step of irradiating light on the material of the active material for the secondary battery that has been densified and a step of receiving reflected light or transmitted light emitted from the material by the irradiated light. The analysis of the color measurement result from the obtained measurement data is also performed by the photoelectric colorimeter 20 (S505). Step S505 is a step of calculating a color value from the received light. It is determined whether the product is a non-defective product or a defective product as an active material for the secondary battery from a database of non-defective products and defective products based on the correlation between the color measurement result and the battery characteristic evaluation that has been built in advance (S506). In step S506, the calculated color value is compared with the color value calculated in advance by the non-defective product, and depending on whether or not the calculated color value is within a specified range based on the color value by the non-defective product, for the secondary battery. This is a step of determining whether or not the material of the active material is a non-defective product. A part of the active material for the secondary battery may be deformed into a pellet shape by the compacting operation, but it is easily crushed by the kneading operation, which is an essential step in electrode production.

  When it is determined that the secondary battery active material is a non-defective product (S507: YES), there is no particular additional operation, and the secondary battery active material simply moves on the conveyor 28.

  If the active material for the secondary battery is determined to be defective (S508: NO), the conveyor 28 is stopped (S509), and the cause of the defective product is investigated (S510).

  As described above, the described embodiment has the following effects.

  By supplying the secondary battery active material to the inspection system of the present embodiment, compacting with the compacting jig 31, measuring and analyzing with the photoelectric colorimeter 20 to obtain the color, non-defective / defective product Can be determined. Moreover, in addition to the effect of 3rd Embodiment, the building height which accommodates the whole test | inspection system can be made low.

  Furthermore, according to this embodiment, it is also possible to inspect indirectly the firing conditions, pulverization conditions, mixing degree, particle size adjustment conditions, and composition of the secondary battery active material intermediate.

(Sixth embodiment)
FIG. 10 is a diagram showing a schematic configuration of an inspection system for an active material for a secondary battery in the sixth embodiment of the present invention. FIG. 11 is a plan view of the inspection system of FIG.

  As shown in FIG. 10, the secondary battery active material inspection system of the present embodiment includes a hopper 1, a hopper discharge port 2, a measurement tube 3, a discharge valve 4, an incident window 6, an observation window 7, a cylindrical lower portion 8, An outlet tube 9, a light source 10, a spectroscope 11, a color CCD image sensor 12, a measurement chamber 13, a defective product collection valve 14, a defective product collection tray 15, a vibration unit 33, and an external computer 19 are provided. Here, the spectrophotometer described in the second embodiment may be used in place of the light source 10 + color CCD image sensor 12, and the light source 10 + color CCD image sensor 12 + external electronic calculator 19 is described in the third embodiment. A photoelectric colorimeter 20 may be used.

  The hopper 1 is connected to the measurement pipe 3 via the hopper discharge port 2. At the lower part of the measurement pipe 3, the outlet pipe 9 and the defective product collection tray 15 are respectively connected via the discharge valve 4 and the defective product collection valve 14. Connected. In the measurement chamber 13, an incident window 6, an observation window 7, a light source 10, a spectroscope 11, and a color CCD image sensor 12 are provided. However, a part or all of the measuring tube 3, a part or all of the cylindrical lower part 8, and the discharge valve 4 may not be in the measuring chamber 13.

  The vibration part 33 functions as a vibration means for vibrating the material of the secondary battery active material to increase the density.

  The measurement chamber 13 has a function for eliminating the influence of an external light source during color measurement. The outlet tube 9 has a function of transporting the active material for the secondary battery after the inspection to the next process, and also has a function of separating non-defective products or defective products into different systems as shown in FIG. The wavelength of the light source 10 is preferably 200 to 900 nm, more preferably 300 to 800 nm. The spectroscope 11 has a function of splitting light emitted from the light source 10. The entrance window 6 and the observation window 7 are made of a material that transmits light. The hopper discharge port 2 may have a valve function. The color CCD image sensor 12 photographs the active material for the secondary battery through the observation window 7 and measures the color.

  In the inspection system for the active material for the secondary battery according to the present embodiment configured as described above, a non-defective product or a defective product is used as the active material for the secondary battery based on the color measurement value obtained by photographing with the color CCD image sensor 12. It is determined whether there is any. Hereinafter, the inspection system for the active material for the secondary battery of the present embodiment will be described with reference to FIGS.

  FIG. 12 is a flowchart showing the inspection process of the secondary battery active material inspection system shown in FIGS. As described above, in the secondary battery active material inspection system according to the present embodiment, whether the active material for the secondary battery is a non-defective product or a defective product based on the color measurement values obtained by the color CCD image sensor 12. Is determined.

  As shown in FIG. 10, in the inspection system for an active material for a secondary battery of the present embodiment, first, the discharge valve 4 is closed (S601). In this embodiment, closing the discharge valve 4 prevents the active material for the secondary battery from flowing below the discharge valve 4.

  Next, the secondary battery active material is supplied to the hopper 1 (S602). The supplied secondary battery active material stays in the measuring tube 3 through the hopper discharge port 2. Depending on the supply amount, the active material for the secondary battery staying in the measuring tube 3 gradually increases and reaches the upper part from the entrance window 6 and the observation window 7. While the secondary battery active material is below the hopper discharge port 2, the supply of the secondary battery active material is stopped (S603). That is, at this time, the space between the hopper discharge port 2 and the discharge valve 4 in the measurement tube 3 is filled with the active material for the secondary battery.

  The portion of the measurement tube 3 that is related to color measurement is vibrated to fill the active material for the secondary battery existing in the measurement tube 3 and increase the density (S604). Step S604 is a stage in which the material of the active material for the secondary battery is compressed to increase the density. This operation increases the reproducibility of color measurement.

  Color measurement is performed by photographing the active material for the secondary battery filled in step S604 with the color CCD image sensor 12 (S605). Step S605 is a step of irradiating light on the material of the active material for the secondary battery having a high density, and a step of receiving reflected light or transmitted light emitted from the material by the irradiated light. The photographing data photographed by the color CCD image sensor may be any of reflection, transmission and refraction by the active material for the secondary battery of the light source 10, but is preferably reflection. Whether it is reflection, transmission, or refraction is determined by the positional relationship of the measurement tube 3, the observation window 7, the light source 10, the spectroscope 11, and the color CCD image sensor 12. The analysis of the color measurement result from the obtained photographing data is preferably performed by an external electronic computer connected by a wired or wireless known method from the viewpoint of the certainty of the analysis (S606). Step S606 is a step of calculating a color value from the received light. It is determined whether the active material for the secondary battery is a non-defective product or a defective product from the database of non-defective products and defective products based on the correlation between the color measurement result and the battery characteristic evaluation that are built in advance (S607). In step S607, the calculated color value is compared with the color value calculated in advance according to the non-defective product, and depending on whether the calculated color value is within a specified range based on the color value based on the non-defective product, This is a step of determining whether or not the material of the active material is a non-defective product.

  If it is determined that the secondary battery active material is a non-defective product (S608: YES), the defective product recovery valve 14 is closed to prevent the secondary battery active material from entering the defective product recovery tray 15 (S609). Further, the discharge valve 4 is opened, and the secondary battery active material staying in the measuring tube 3 flows to the next step through the branch pipe in the figure (S610). At that time, a part of the active material for the secondary battery may be deformed into a pellet shape by the compacting operation, but it is easily crushed by the kneading operation, which is an essential step in electrode production.

  When it is determined that the active material for the secondary battery is a defective product (S611: NO), the defective product recovery valve 14 is opened (S612). Further, when the discharge valve 4 is opened, the active material for the secondary battery is recovered in the defective product recovery tray 15 (S613).

  As described above, the described embodiment has the following effects.

  The secondary battery active material is supplied to the inspection system of the present embodiment, a part of the measuring tube 3 is vibrated, the secondary battery active material is filled, and the color CCD image sensor 12 is photographed. Non-defective / defective products can be determined by measuring and analyzing data and obtaining colors. Furthermore, according to this embodiment, it is also possible to inspect indirectly the firing conditions, pulverization conditions, mixing degree, particle size adjustment conditions, and composition of the secondary battery active material intermediate.

Example 1
The specific example of the active material for secondary batteries is demonstrated based on the positive electrode active material E-1 for lithium ion secondary batteries. The active material for a secondary battery according to the present invention is not limited to the positive electrode active material E-1 for a lithium ion secondary battery.

(1) Preparation of positive electrode active material E-1 for lithium ion secondary battery
Nickel (II) sulfate hexahydrate, manganese (II) sulfate tetrahydrate, and cobalt (II) sulfate heptahydrate have a molar ratio of each transition metal element of Ni: Mn: Co = 17: 56: 7. A 2 mol / L aqueous sulfate solution was prepared by weighing and adding to ion exchange water. The temperature of this aqueous sulfate solution was controlled at 25 ° C. and stirred at a constant rate. To this sulfate aqueous solution, a 0.2 mol / L ammonium hydroxide aqueous solution was dropped at a constant rate to adjust the pH value to 7.5. Thereafter, a 0.2 mol / L aqueous ammonium hydroxide solution and a 2 mol / L aqueous sodium carbonate solution were added dropwise at a constant rate while maintaining the pH value at 7.5 to obtain a precipitate A-1. . Precipitate A-1 was washed with ion exchange water and suction filtered to remove excess water. Furthermore, in a dryer maintained at a temperature of 120 ° C., a trace amount of water was removed by evaporation to obtain a composite hydroxide B-1. The composite hydroxide B-1 was calcined in an air atmosphere at a temperature of 500 ° C. and a holding time of 5 hours to obtain a composite oxide C-1. The composite oxide C-1 was subjected to composition analysis by ICP emission spectroscopic analysis and confirmed to be consistent with the charged composition. The mixed oxide powder C-1 and lithium hydroxide monohydrate are mixed and pulverized so that the molar ratio of each element is Li: Ni: Mn: Co = 125: 17: 56: 7. D-1 was obtained. The mixed raw material powder D-1 was held and fired at 900 ° C. for 12 hours in an air atmosphere to obtain positive electrode active material particles E-1 for a lithium ion secondary battery.

(2) Powder X-ray diffraction measurement
With respect to the positive electrode active material particles E-1 for lithium ion secondary batteries obtained in (1), powder X-ray diffraction was measured. The measurement was performed under the following conditions using RU-200 (rotary counter cathode type) manufactured by Rigaku Corporation.

X-ray: CuKα
Voltage-current: 50kV-200mA
Measurement angle range: 2θ = 10-100 °
Step: 0.02 °
Scanning speed: 1 ° / min
The result of the powder X-ray diffraction measurement of the positive electrode active material particle E-1 for a lithium ion secondary battery is shown in FIG. The observed peak was assigned to either Li ₂ MnO ₃ or LiNiO ₂ .

(3) Measurement of color value
When the positive electrode active material E-1 for a lithium ion secondary battery obtained in (1) was measured by the inspection system of the second embodiment described in the present invention, L * which is a color space defined by JIS Z 8729 The color coordinates of the a * b * color system were a = 4.36, b = 2.09, and L = 17.89. The true density was 5 g / cm ³ .

(4) Preparation of lithium ion secondary battery
A positive electrode for a lithium ion secondary battery was obtained by kneading 20 mg of a positive electrode active material E-1 for a lithium ion secondary battery and 12 mg of TAB-2, which is a conductive auxiliary agent / binder, and then forming a pellet.

Molar ratio of ethylene carbonate (EC) and diethyl carbonate (DMC) containing 1.0 M LiPF ₆ as the electrolyte, Li metal as the separator, glass filter paper as the separator, and positive electrode for the lithium ion secondary battery prepared above. A coin-type bipolar cell was prepared using the (1: 2) mixed solution.

(5) Measurement of charge / discharge capacity
After the coin-type bipolar cell was fabricated and 24 hours had passed, a charge / discharge test using constant current and constant voltage charge and constant current discharge was started under the following conditions.
Charging: Charging voltage 4.8V, charging time 8 hours, charging current density 0.2 mA / cm ²
Discharge: Discharge voltage 2.0 V, discharge current density 0.2 mA / cm ²
However, the upper limit voltage was changed to 4.5, 4.6, 4.7 V every 2 cycles as formation, and the test was carried out as the above charge / discharge conditions later. The obtained discharge capacity was 275 mAh / g.

(Example 2)
(1) Preparation of positive electrode active material E-2 for lithium ion secondary battery
The mixed oxide C-1 and lithium hydroxide monohydrate in Example 1 were mixed and pulverized so that the molar ratio of each element was Li: Ni: Mn: Co = 135: 17: 56: 7. The positive electrode active material particle E-2 for lithium ion secondary batteries was obtained by synthesizing in the same procedure as in Example 1.

(2) Measurement of color value
When the positive electrode active material E-2 for a lithium ion secondary battery obtained in (1) was measured by the inspection system according to the second embodiment of the present invention, L * which is a color space defined by JIS Z 8729 The color coordinates of the a * b * color system were a = 2.11, b = −1.10, and L = 19.52. The true density was 5 g / cm ³ .

(3) Preparation of lithium ion secondary battery It produced by the same procedure except having used E-2 as a positive electrode active material for lithium ion secondary batteries.

(4) Measurement of charge / discharge capacity
When measured in the same procedure as in Example 1, the obtained discharge capacity was 256 mAh / g.

(Example 3)
(1) Preparation of positive electrode active material E-3 for lithium ion secondary battery
The composite oxide C-1 and lithium hydroxide monohydrate in Example 1 were mixed and pulverized so that the molar ratio of each element was Li: Ni: Mn: Co = 140: 17: 56: 7. The positive electrode active material particle E-3 for lithium ion secondary batteries was obtained by synthesizing in the same procedure as in Example 1.

(2) Measurement of color value
When the positive electrode active material E-3 for lithium ion secondary battery obtained in (1) was measured by the inspection system of the second embodiment described in the present invention, L * which is a color space defined by JIS Z 8729 The color coordinates of the a * b * color system were a = 1.68, b = −0.95, and L = 19.18. The true density was 5 g / cm ³ .

(3) Creation of lithium ion secondary battery
The same procedure as in Example 1 was used except that E-3 was used as the positive electrode active material for the lithium ion secondary battery.

(4) Measurement of charge / discharge capacity
When measured by the same procedure as in Example 1, the obtained discharge capacity was 245 mAh / g.

Example 4
(1) Preparation of positive electrode active material E-4 for lithium ion secondary battery
The mixed oxide C-1 and lithium hydroxide monohydrate in Example 1 were mixed and pulverized so that the molar ratio of each element was Li: Ni: Mn: Co = 145: 17: 56: 7. The positive electrode active material particle E-4 for lithium ion secondary batteries was obtained by synthesizing in the same procedure as in Example 1.

(2) Measurement of color value
When the positive electrode active material E-4 for lithium ion secondary battery obtained in (1) was measured by the inspection system of the second embodiment described in the present invention, L * which is a color space defined by JIS Z 8729 The color coordinates of the a * b * color system were a = 1.60, b = −0.92, and L = 19.98. The true density was 5 g / cm ³ .

(3) Creation of lithium ion secondary battery
The same procedure as in Example 1 was used except that E-4 was used as the positive electrode active material for the lithium ion secondary battery.

(4) Measurement of charge / discharge capacity
When measured in the same procedure as in Example 1, the obtained discharge capacity was 220 mAh / g.

(Example 5)
(1) Preparation of positive electrode active material E-5 for lithium ion secondary battery
The mixed raw material powder D-1 in Example 1 was synthesized in the same procedure as in Example 1 except that the firing temperature was 700 ° C., to obtain positive electrode active material particles E-5 for a lithium ion secondary battery. .

(2) Measurement of color value
When the positive electrode active material E-5 for lithium ion secondary battery obtained in (1) was measured by the inspection system of the second embodiment described in the present invention, L * which is a color space defined by JIS Z 8729 The color coordinates of the a * b * color system were a = 5.70, b = 5.81, and L = 18.51. The true density was 5 g / cm ³ .

(3) Creation of lithium ion secondary battery
The same procedure as in Example 1 was used except that E-5 was used as the positive electrode active material for the lithium ion secondary battery.

(4) Measurement of charge / discharge capacity
When measured by the same procedure as in Example 1, the obtained discharge capacity was 245 mAh / g.

(Example 6)
(1) Preparation of positive electrode active material E-6 for lithium ion secondary battery
The mixed raw material powder D-1 in Example 1 was synthesized in the same procedure as in Example 1 except that the firing temperature was 1000 ° C., to obtain positive electrode active material particles E-6 for a lithium ion secondary battery. .

(2) Measurement of color value
When the positive electrode active material E-6 for lithium ion secondary battery obtained in (1) was measured by the inspection system of the second embodiment described in the present invention, L * which is a color space defined by JIS Z 8729 The color coordinates of the a * b * color system were a = 2.43, b = −1.20, and L = 18.94. The true density was 5 g / cm ³ .

(3) Creation of lithium ion secondary battery
The same procedure as in Example 1 was used, except that E-6 was used as the positive electrode active material for the lithium ion secondary battery.

(4) Measurement of charge / discharge capacity
When measured by the same procedure as in Example 1, the obtained discharge capacity was 201 mAh / g.

(result)
As shown in Table 1, as shown in Examples 1 to 4 in the production of an active material for a secondary battery, when the ratio of each element of the material of the active material for the secondary battery is different, the L * a * b * system The Lab value of color system color coordinates and the discharge capacity change. Therefore, if it is determined whether or not the material of the active material for the secondary battery is a non-defective product based on a predetermined discharge capacity value, the region of the non-defective product is determined in the L * a * b * color system color coordinate. Can do non-destructive inspections.

  Further, as shown in Examples 1, 5, and 6 in the production of the active material for the secondary battery, the L * a * b * system color system color when the conditions for burning the material of the active material for the secondary battery are different. The Lab Lab value and the discharge capacity change. Therefore, similarly, if it is determined whether or not the material of the active material for the secondary battery is a non-defective product based on a predetermined discharge capacity value, it is determined whether or not it is a non-defective product in the L * a * b * system color system color coordinates. The area can be determined and non-destructive inspection can be done.

  As described above, in the inspection system for the active material for secondary battery in the first to sixth embodiments of the present invention, the density of the material of the active material for secondary battery is increased and the color value is obtained. Can be determined. Furthermore, the firing conditions, pulverization conditions, mixing degree, particle size adjustment conditions, and composition of the active material intermediate for a secondary battery can be inspected for each step. Therefore, by pre-processing to compress and densify the material of the active material for secondary batteries, the light is irradiated on the material, and the secondary light from the material is analyzed and the inspection is performed with the color value obtained Can provide a simple inspection system. Further, a part of the material of the secondary battery active material may be deformed into a pellet shape by compression, but can be easily crushed by a kneading operation. Therefore, it is possible to provide a non-destructive inspection system that does not waste the material of the active material for the secondary battery. In addition, there is no concern about industrial waste and the cost can be reduced.

  It goes without saying that the present invention can be appropriately added, modified, and omitted by those skilled in the art within the scope of the technical idea.

It is a figure which shows schematic structure of the inspection system of the active material for secondary batteries in 1st Embodiment. It is a top view of the inspection system of the active material for secondary batteries in a 1st embodiment. It is a top view of the inspection system of the active material for secondary batteries in a 1st embodiment. It is a top view of the inspection system of the active material for secondary batteries in a 1st embodiment. It is a top view of the inspection system of the active material for secondary batteries in a 1st embodiment. It is a flowchart which shows the test | inspection process of the test | inspection system of the active material for secondary batteries in 1st Embodiment. It is a figure which shows schematic structure of the inspection system of the active material for secondary batteries in 2nd Embodiment. It is a figure which shows schematic structure of the inspection system of the active material for secondary batteries in 3rd Embodiment. It is a figure which shows schematic structure of the inspection system of the active material for secondary batteries in 4th Embodiment. It is a flowchart which shows the test | inspection process of the test | inspection system of the active material for secondary batteries in 4th Embodiment. It is a figure which shows schematic structure of the inspection system of the active material for secondary batteries in 5th Embodiment. It is a flowchart which shows the test | inspection process of the test | inspection system of the active material for secondary batteries in 5th Embodiment. It is a figure which shows schematic structure of the inspection system of the active material for secondary batteries in 6th Embodiment. It is a top view of the test | inspection system of the active material for secondary batteries in 6th Embodiment. It is a flowchart which shows the test | inspection process of the test | inspection system of the active material for secondary batteries in 6th Embodiment. It is a figure which shows the result of the powder X-ray-diffraction measurement of the positive electrode active material particle for secondary batteries.

Explanation of symbols

1 hopper,
2 Hopper outlet 3 Measuring tube,
4 discharge valve,
5 Pressing guide,
6 Entrance window,
7 Observation window,
8 Lower part of cylinder,
9 outlet pipe,
10 light source,
11 Spectrometer,
12 image sensor,
13 Measuring humidity,
14 Defective product recovery valve,
15 Defective product collection tray
17 Green compact receiver,
18 Spectrophotometer,
19 External electronic computer,
20 Photoelectric colorimeter,
28 belt conveyor,
33 Vibrating part.

Claims (6)

A vibration means Ru is densified by vibrating the material of the active material for a secondary battery,
Irradiating means for irradiating the densified material with light;
Light receiving means for receiving reflected light or transmitted light emitted from the densified material by the light irradiated by the irradiation means, and outputting a signal based on the received light;
Calculating means for calculating a color value from the signal;
The color value calculated by the calculation means is compared with the color value calculated by the good product in advance, and whether the calculated color value is a value within a specified range based on the color value by the good product,
Determining means for determining whether or not the material of the active material for the secondary battery is a non-defective product;
Including inspection system. The active material for a secondary battery has a composition formula of LiwNixMnyCozO ₂ + δ,
W, x, y, z and δ in the formula are 1.1 <w <1.5, 0.1 <x <0.4, 0.4 <
Substance satisfying y <0.9, 0 <z <0.2, w + x + y + z = 2, −0.2 <δ <0.2
Inspection system according to claim 1, characterized in that. The inspection system according to claim 1 or 2 , wherein the material of the secondary battery active material is a powdery substance . Vibrating the material of the active material for the secondary battery to increase the density,
Irradiating the increased density material with light;
Reflected or transmitted light emitted from the increased density material by the irradiated light
Receiving light, and
Calculating a color value from the received light;
The calculated color value is collated with a pre-calculated non-defective color value, and the calculated color value
Depending on whether the value is within a specified range based on the color value of the non-defective product, the secondary power
Determining whether the material of the pond active material is a non-defective product,
Including inspection methods . The active material for a secondary battery has a composition formula of LiwNixMnyCozO ₂ + δ,
W, x, y, z and δ in the formula are 1.1 <w <1.5, 0.1 <x <0.4, 0.4 <
The inspection method according to claim 4 , wherein the inspection method satisfies the following conditions: y <0.9, 0 <z <0.2, w + x + y + z = 2, and −0.2 <δ <0.2 . 6. The inspection method according to claim 4, wherein the material of the secondary battery active material is a powdery material.