JP2015076278A - Device for producing slurry for electrode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for producing a slurry for an electrode, capable of easily adjusting a viscosity of a slurry for an electrode to a target value.SOLUTION: A production device 1 is a device for producing a slurry for an electrode, which produces a slurry for an electrode using a solvent and a raw material including a powder material and a paste material. The production device 1 includes: an input reception part 11 for receiving at least one of inputs of a density of the powder material for each lot of the powder material, a DBP oil absorption amount of the powder material for each lot of the powder material, and a viscosity of the paste material for each lot of the paste material; a calculation part 13 preliminary holding a target value of a viscosity of the slurry for an electrode, and calculating a dilution amount of the raw material by the solvent for adjusting a viscosity of the slurry for an electrode to a target value according to at least one of a density of the powder material, a DBP oil absorption amount of the powder material, and a viscosity of the paste material, the inputs of which have been received by the input reception part 11; and a dilution part 20 preparing the slurry for an electrode by diluting the raw material with the solvent at the dilution amount calculated by the calculation part 13.

Description

  The present invention relates to an electrode slurry manufacturing apparatus.

  Conventionally, as a technique for manufacturing an electrode of a power storage device, for example, a powdery lithium transition metal composite oxide, a binder, and a conductive additive are diluted with a solvent to prepare a slurry, and the slurry is coated on a metal. A technique for producing a positive electrode of a secondary battery by applying and drying the film on the substrate is known (for example, see Patent Document 1). In the technique described in Patent Document 1, after spray-drying a transition metal compound or the like, a lithium compound is added and mixed, the mixture is fired, and then pulverized and classified to obtain a powdered lithium transition metal composite oxide. To manufacture.

JP 2007-5238 A

  By the way, various physical property values of powder materials such as lithium transition metal composite oxides vary from lot to lot. Therefore, the viscosity of the slurry prepared by mixing the powder material and a paste material such as a binder and diluting with a solvent may also vary due to variations in the physical properties of the powder material. . When the viscosity of the slurry varies, the quality of the power storage device obtained using the slurry may also vary. Although it is possible to finely adjust the viscosity of the slurry by actually measuring the viscosity of the prepared slurry and adjusting the dilution amount based on the measured viscosity, this increases labor costs and processing time. There is a problem of doing.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide an apparatus for producing an electrode slurry that can easily adjust the viscosity of the electrode slurry to a target value.

  In order to solve the above-mentioned problems, an electrode slurry manufacturing apparatus according to the present invention is an electrode slurry manufacturing apparatus that manufactures an electrode slurry using a raw material including a powder material and a paste material and a solvent. An input receiving unit for receiving at least one of the density of the powder material for each lot of the body material, the DBP (dibutyl phthalate) oil absorption amount, and the viscosity of the paste material for each lot of the paste material; and the viscosity of the slurry for the electrode To hold the target value in advance and set the viscosity of the electrode slurry to the target value based on at least one of the density of the powder material, the DBP oil absorption amount, and the viscosity of the paste material that has been input by the input receiving unit. A calculation unit that calculates the dilution amount of the raw material with the solvent of the electrode, and the electrode slurry by diluting the raw material with the solvent of the dilution amount calculated by the calculation unit Comprising a Seisuru preparation unit.

  According to the present invention, based on at least one of the density of the powder material for each lot, the DBP oil absorption amount, and the viscosity of the paste material for each lot, the dilution amount for setting the viscosity of the electrode slurry to the target value is Calculated by the calculation unit, the raw material is diluted with the diluted amount of the solvent to prepare an electrode slurry. Therefore, even if the density of the powder material for each lot, the DBP oil absorption amount, and the viscosity of the paste material for each lot vary, it is possible to always adjust the viscosity of the prepared electrode slurry to the target value. Since the calculation of the dilution amount is automatically executed by the calculation unit, it is not necessary to actually measure the viscosity of the prepared slurry, and the viscosity of the slurry can be easily finely adjusted.

  The input receiving unit includes a reading unit that reads an information code representing at least one of the density of the powder material for each lot of the powder material, the DBP oil absorption, and the viscosity of the paste material for each lot of the paste material. Is preferred. In this case, the input of information to the input receiving unit becomes simpler and the convenience can be improved.

  It is preferable that the density of the powder material received by the input receiving unit is a tap density. The tap density is a parameter that particularly strongly affects the viscosity of the slurry. Therefore, by using the tap density as the density of the powder material, the viscosity of the prepared electrode slurry can be adjusted to the target value with higher accuracy.

  According to the present invention, the viscosity of the electrode slurry can be easily adjusted to the target value.

It is a schematic diagram which shows the structure of a manufacturing apparatus. It is a graph which shows the relationship between the tap density of powder material, and the viscosity of the slurry for electrodes of a predetermined solid content rate. It is a graph which shows the relationship between the viscosity of paste material, and the viscosity of the slurry for electrodes of a predetermined | prescribed solid content rate. It is a graph which shows the relationship between the viscosity of the slurry for electrodes of a predetermined | prescribed solid content rate, and the solid content rate of the slurry for electrodes at the time of completion. It is a graph which shows the relationship between the oil absorption amount of an active material, and the viscosity of the slurry for electrodes of a predetermined solid content rate. It is a graph which shows the relationship between the viscosity of paste material, and the viscosity of the slurry for electrodes of a predetermined | prescribed solid content rate. It is a graph which shows the relationship between the viscosity of the slurry for electrodes of a predetermined | prescribed solid content rate, and the solid content rate of the slurry for electrodes at the time of completion. It is a schematic diagram which shows the measurement process of the density of powder material.

  Hereinafter, a preferred embodiment of an electrode slurry manufacturing apparatus according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic diagram illustrating a configuration of an apparatus 1 for producing an electrode slurry SL according to an embodiment of the present invention. The manufacturing apparatus 1 shown in the figure is an apparatus for manufacturing an electrode slurry SL using a raw material including a powder material P and a paste material B and a solvent S. The electrode slurry SL manufactured by the manufacturing apparatus 1 is used to manufacture an electrode of a power storage device such as a secondary battery by being coated on the surface of a metal foil such as aluminum or copper.

  The powder material P is, for example, an active material. The active material may be either a positive electrode active material or a negative electrode active material. The powder material P may contain a conductive additive such as carbon black and acetylene black. Examples of the positive electrode active material include composite oxide, metallic lithium, and sulfur. The composite oxide includes at least one of manganese, nickel, cobalt, iron, and aluminum and lithium.

  Examples of the negative electrode active material include graphite, highly oriented graphite, carbon such as mesocarbon microbeads, hard carbon, and soft carbon, alkali metals such as lithium and sodium, metal compounds, silicon-based materials such as Si and SiOx, Sn , Sn-based materials such as SnOx, boron-added carbon and the like.

  The paste material B is, for example, a binder. Examples of the binder include PVdF (polyvinylidene fluoride), PTFE (polytetrafluoroethylene), SBR (styrene / butadiene rubber), NBR (nitrile / butadiene rubber), CMC (carboxymethylcellulose), polyacrylic acid, polyamideimide, and polyimide. Etc. The solvent S may be an organic solvent such as NMP (N-methylpyrrolidone), methanol, methyl isobutyl ketone, or water.

  The manufacturing apparatus 1 illustrated in FIG. 1 includes an input receiving unit 11 that receives at least one input of density of raw materials, DBP oil absorption, and viscosity, and dilution of raw materials based on information received by the input receiving unit. The calculation part 13 which calculates quantity, and the dilution part 20 which dilutes a raw material with the solvent S of the dilution amount calculated by the calculation part 13 are provided.

  The input receiving unit 11 is a part that receives at least one of the density of the powder material P for each lot, the DBP oil absorption amount, and the viscosity of the paste material B for each lot. The input receiving unit 11 includes, for example, a reading unit 12 that reads an information code C that represents at least one of the density of the powder material P for each lot, the DBP oil absorption amount, and the viscosity of the paste material B for each lot. For example, the reading unit 12 decodes the acquired image information, such as a scanner or a camera for acquiring image information, and the density of the powder material P included in the information code C, the DBP oil absorption amount. Or it is comprised by the information read-out part etc. which read the viscosity of the paste material B, etc. As the information code C, for example, a QR code (registered trademark) or a barcode can be used. The information code C is printed on, for example, a delivery specification DS for each lot of the powder material P or the paste material B.

  The density of the powder material P received by the input receiving unit 11 is, for example, a tap density. The number of taps when measuring the tap density is not particularly limited, but is, for example, 250 times. Further, as the density of the powder material P, a bulk density obtained by measuring the volume without tapping after the powder material P is put in the container may be used. In addition, as the density of the powder material P, the powder material P is put into a liquid in which the powder material P is insoluble, and the volume of the powder material P is calculated based on the rise of the liquid level of the liquid. You may use the density obtained by dividing the mass of the powder material P thrown into the liquid by the calculated volume.

  The calculation unit 13 is a part that calculates the dilution amount of the raw material by the solvent S. The calculation unit 13 holds in advance a target value of the viscosity of the electrode slurry SL in a storage unit such as a memory (not shown). Then, the calculation unit 13 calculates the dilution amount based on at least one of the density of the powder material P, the DBP oil absorption amount, and the viscosity of the paste material B that are input by the input reception unit 11. The calculation unit 13 can be physically configured by, for example, a microprocessor and a memory. A specific method for calculating the dilution amount will be described later.

  The dilution unit 20 is a part that prepares the electrode slurry SL by diluting the raw material with the amount of the solvent S calculated by the calculation unit 13. The dilution unit 20 includes, for example, a solvent storage tank 21, a powder material storage tank 22, a paste material storage tank 23, a mixing tank 24, valves 25A to 25C, and a control unit 27. The solvent storage tank 21 is a container for storing the solvent S. The powder material storage tank 22 is a container for storing the powder material P. The paste material storage tank 23 is a container for storing the paste material B. The mixing tank 24 mixes the powder material P stored in the powder material storage tank 22 and the paste material B stored in the paste material storage tank 23, and adds the solvent S stored in the solvent storage tank 21. A container for dilution.

  The valves 25 </ b> A to 25 </ b> C are respectively provided on pipes 26 </ b> A to 26 </ b> C extending from the solvent storage tank 21, the powder material storage tank 22, and the paste material storage tank 23 to the mixing tank 24. By opening and closing the valves 25A to 25C, the solvent S and the powder material supplied from the solvent storage tank 21, the powder material storage tank 22 and the paste material storage tank 23 to the mixing tank 24 via the pipes 26A to 26C. The supply amounts of P and paste material B are adjusted.

  The control unit 27 is a part that controls opening and closing of the valves 25 </ b> A to 25 </ b> C according to the dilution amount calculated by the calculation unit 13. The control unit 27 may control the valves 25 </ b> A to 25 </ b> C so that all the amounts of the solvent S, the powder material P, and the paste material B supplied to the mixing tank 24 are variable. Alternatively, the control unit 27 controls the valve 25A so that only the amount of the solvent S is variable according to the dilution amount, and the amount of the powder material P and the paste material B is the density of the powder material P, DBP oil absorption The valves 25B and 25C may be controlled to be constant regardless of the amount and the viscosity of the paste material B.

  The manufacturing apparatus 1 configured as described above operates as follows. First, the reading unit 12 of the input receiving unit 11 reads the information code C printed on the delivery specification DS for each lot of at least one of the powder material P and the paste material B. The input receiving unit 11 decodes the information code C and reads at least one information of the density of the lot of the powder material P, the DBP oil absorption amount, and the viscosity of the lot of the paste material B. The input reception unit 11 outputs the read tap density, DBP oil absorption amount, or viscosity information to the calculation unit 13.

  The calculation unit 13 calculates the dilution amount based on at least one of the density of the lot of the powder material P, the DBP oil absorption amount, and the viscosity of the lot of the paste material B read by the input reception unit 11. The control unit 27 of the dilution unit 20 opens and closes the valves 25 </ b> A to 25 </ b> C based on the dilution amount calculated by the calculation unit 13. The solvent S, the powder material P, and the paste material B are supplied to the mixing tank 24 from the solvent storage tank 21, the powder material storage tank 22, and the paste material storage tank 23, respectively, according to opening and closing of the valves 25A to 25C. . In the mixing tank 24, the powder material P and the paste material B are mixed and further diluted with the solvent S, whereby the electrode slurry SL is manufactured. The manufactured electrode slurry SL is discharged from the mixing tank 24 to the subsequent stage.

  As described above, according to the manufacturing apparatus 1 of the present embodiment, based on at least one of the density of the powder material P for each lot, the DBP oil absorption amount, and the viscosity of the paste material B for each lot, A dilution amount for setting the viscosity of the slurry SL to the target value is calculated by the calculation unit 13, and the raw material is diluted with the solvent S of this dilution amount to prepare the electrode slurry SL. Therefore, even if the density of the powder material P for each lot, the DBP oil absorption amount, and the viscosity of the paste material B for each lot vary, the viscosity of the prepared electrode slurry SL can always be adjusted to the target value. . Since the calculation of the dilution amount is automatically executed by the calculation unit 13, it is not necessary to actually measure the viscosity of the prepared electrode slurry SL, and the viscosity of the electrode slurry SL can be easily finely adjusted.

  The input receiving unit 11 includes a reading unit 12 that reads an information code C representing at least one of the density of the powder material P for each lot, the DBP oil absorption amount, and the viscosity of the paste material B for each lot. With this configuration, it is easier to input information to the input receiving unit 11, and convenience is improved.

  When the density of the powder material P received by the input receiving unit 11 is a tap density, the tap density is a parameter that particularly strongly affects the viscosity of the electrode slurry SL. By using the tap density, the viscosity of the prepared electrode slurry SL can be adjusted to the target value with higher accuracy.

(Example of how to calculate dilution amount)
An embodiment of a method for calculating the dilution amount by the calculation unit 13 will be described. In the present embodiment, the electrode slurry SL manufactured by the manufacturing apparatus 1 is a positive electrode slurry. The powder material P contains nickel cobalt lithium manganate as an active material and carbon black as a conductive additive. Paste material B contains PVdF as a binder. The solvent S contains NMP (N-methylpyrrolidone).

Prior to calculating the dilution amount, the relationship between the tap density of the powder material P and the viscosity of the slurry having a predetermined solid content ratio obtained by mixing the powder material P having the tap density with the paste material B is examined in advance. deep. FIG. 2 is an example of the relationship between the tap density of the powder material P and the viscosity of the slurry having a predetermined solid content (70% by weight). The horizontal axis represents the tap density (unit: g / cm ³ ) of the powder material P. The vertical axis represents the viscosity (unit: cP) of a slurry having a predetermined solid content (70% by weight). In FIG. 2, the viscosity of the paste material B is fixed at 1000 cP. The five points on FIG. 2 are plots of the results obtained by actually measuring the viscosity of the slurry diluted with the tap density of the powder material P in five ways to obtain a predetermined solid content (70% by weight). It is. The straight line in FIG. 2 is an approximate straight line showing the relationship between the tap density of the powder material P and the viscosity of the slurry having a predetermined solid content ratio, which is obtained from five actually measured values. If the tap density of the powder material P is x and the viscosity of the slurry having a predetermined solid content is y, it can be approximated as y = -11650x + 32881.

Similarly, prior to the calculation of the dilution amount, the relationship between the viscosity of the paste material B and the viscosity of the slurry having a predetermined solid content obtained by mixing the paste material B having the viscosity with the powder material P is examined in advance. deep. FIG. 3 is an example of the relationship between the viscosity of the paste material B and the viscosity of the slurry having a predetermined solid content (70% by weight). The horizontal axis represents the viscosity (unit: cP) of the paste material B. The vertical axis represents the viscosity (unit: cP) of a slurry having a predetermined solid content (70% by weight). In FIG. 3, the tap density of the powder material P is fixed at 2.3 g / cm ³ . The five points on FIG. 3 are obtained by actually measuring the viscosity of the slurry diluted so that the paste material B has a predetermined solid content (70% by weight) by changing the viscosity of the paste material B in five ways, and plotting the results. . The straight line of FIG. 3 shows the approximate straight line which shows the relationship between the viscosity of the paste material B and the viscosity of the slurry of a predetermined solid content rate obtained from five kinds of measured values. If the viscosity of the paste material B is x and the viscosity of the slurry having a predetermined solid content is y, it is approximated as y = 3.183x + 2842.1.

When these relationships are integrated, an equation for calculating the viscosity of the slurry having a predetermined solid content ratio based on the tap density of the powder material P and the viscosity of the paste material B is obtained as the following equation (1). .
η ₁ = −α (ρ _A −ρ _A0 ) + β (η _B −η _B0 ) + η ₀ (1)

In Formula (1), η ₁ is the viscosity of the slurry having a predetermined solid content rate, η ₀ is the median value of the viscosity of the slurry having the predetermined solid content rate, α is a coefficient related to the tap density of the powder material P, and β is the paste material Coefficient of viscosity of B, ρ _A is the tap density of the powder material P for each lot, ρ _A0 is the median value of the tap density of the powder material P, η _B is the viscosity of the paste material B for each lot, η _B0 is This is the median viscosity of the paste material B. In the case of the above-described embodiment, for example, if η ₀ = 6056, α = 1650, β = 3.183, ρ _A0 = 2.3, and η _B0 = 1000, the viscosity η ₁ of the slurry having a predetermined solid content is reduced to the powder. It can be calculated based on the tap density ρ _A of the body material P and the viscosity η _B of the paste material B.

The calculation unit 13 thus calculates the viscosity η ₁ of the slurry having a predetermined solid fraction, and then dilutes the slurry having the predetermined solid fraction with the viscosity η ₁ to finally obtain the viscosity of the electrode slurry SL. Is calculated as a target value.

  FIG. 4 is an example of the relationship between the viscosity of a slurry having a predetermined solid content rate (70 wt%) and the solid content rate at a target viscosity (5000 cP). The horizontal axis represents the viscosity of the slurry having a predetermined solid content (70% by weight). The vertical axis represents the solid content ratio at the target viscosity (5000 cP). The 10 points on FIG. 4 indicate the solid content required to obtain the target viscosity (5000 cP) for the slurry diluted to the predetermined solid content (70 wt%) plotted in FIGS. 2 and 3. The results are plotted. The straight line in FIG. 4 is an approximate straight line showing the relationship between the viscosity of a slurry having a predetermined solid content rate (70 wt%) and the solid content rate at a target viscosity (5000 cP), obtained from 10 actually measured values. When the viscosity of the slurry having a predetermined solid content (70 wt%) is x and the solid content at the target viscosity (5000 cP) is y, y = −0.00096x + 74.95122 is approximated.

From this result, an equation for calculating the solid fraction necessary for obtaining the electrode slurry having the target viscosity based on the viscosity η ₁ of the slurry having the predetermined solid fraction is obtained as the following equation (2). It is done.
M = −γ (η ₁ −η) + M ₁ (2)

In the formula (2), M is a solid content rate required to obtain an electrode slurry having a target viscosity, M ₁ is a solid content rate of a slurry having a predetermined solid content rate, and η ₁ is a viscosity of the slurry having a predetermined solid content rate. , Η is a target viscosity of the electrode slurry SL finally obtained, and γ is a coefficient related to the viscosity. In the case of the above-described embodiment, for example, if M ₁ = 70, η = 5000, and γ = 0.00096, the solid fraction required to obtain the electrode slurry with the target viscosity is the viscosity of the slurry with a predetermined solid fraction. It can be calculated based on η ₁ .

By such a method, the calculation unit 13 can calculate the dilution amount (solid content ratio) of the solvent S based on the tap density ρ _A of the powder material P and the viscosity η _B of the paste material B.

(Another example of how to calculate the dilution amount)
In the above embodiment, the dilution amount is calculated based on the tap density of the powder material P, which is the viscosity of the lot of the paste material B. However, instead of using the density of the powder material P, another index indicating a correlation with the density is used. It may be used. For example, DBP oil absorption can be used. The DBP oil absorption is a physical property value having a negative correlation with the tap density.

  Hereinafter, another example of the calculation method of the dilution amount by the calculation unit 13 will be described. In the present embodiment, the electrode slurry SL manufactured by the manufacturing apparatus 1 is a negative electrode slurry. The powder material P contains natural graphite which is an active material. Paste material B contains a CMC aqueous solution that is a thickener. The solvent S contains water. As the material of the electrode slurry SL, in addition to the powder material P, the paste material B, and the solvent S described above, SBR that exhibits properties as a liquid is used.

  Prior to the calculation of the dilution amount, the relationship between the DBP oil absorption amount of the powder material P and the viscosity of the slurry having a predetermined solid content ratio obtained by mixing the powder material P having the DBP oil absorption amount with the paste material B is previously determined. Check it out. FIG. 5 is an example of the relationship between the DBP oil absorption amount of the powder material P and the viscosity of the slurry having a predetermined solid content rate (60 wt%). The horizontal axis represents the DBP oil absorption (unit: ml / 100 g) of the powder material P. The vertical axis represents the viscosity (unit: cP) of a slurry having a predetermined solid content (60% by weight). In FIG. 5, the viscosity of the paste material B is fixed at 3700 cP. The five points on FIG. 5 are obtained by plotting the viscosity of the slurry diluted to a predetermined solid content (60 wt%) by changing the DBP oil absorption amount of the powder material P in five ways. Is. The straight line in FIG. 5 is an approximate straight line showing the relationship between the DBP oil absorption amount of the powder material P and the viscosity of the slurry having a predetermined solid content, obtained from five actual measurement values. If the DBP oil absorption amount of the powder material P is x and the viscosity of the slurry having a predetermined solid content is y, it is approximated as y = 134.82x-1223.5.

  Similarly, prior to the calculation of the dilution amount, the relationship between the viscosity of the paste material B and the viscosity of the slurry having a predetermined solid content obtained by mixing the paste material B having the viscosity with the powder material P is examined in advance. deep. FIG. 6 is an example of the relationship between the viscosity of the paste material B and the viscosity of the slurry having a predetermined solid content (60% by weight). The horizontal axis represents the viscosity (cP) of the paste material B. The vertical axis represents the viscosity (cP) of the slurry having a predetermined solid content (60% by weight). In FIG. 6, the DBP oil absorption amount of the powder material P is fixed at 54 ml / 100 g. The five points on FIG. 6 are obtained by plotting the results obtained by actually measuring the viscosity of the slurry diluted to have a predetermined solid content (60 wt%) by changing the viscosity of the paste material B in five ways. . The straight line of FIG. 6 shows the approximate straight line which shows the relationship between the viscosity of the paste material B and the viscosity of the slurry of a predetermined solid content rate obtained from five kinds of measured values. If the viscosity of the paste material B is x and the viscosity of the slurry having a predetermined solid content is y, it is approximated as y = 1.8395x−826.67.

When these relationships are integrated, an equation for calculating the viscosity of the slurry having a predetermined solid content based on the DBP oil absorption amount of the powder material P and the viscosity of the paste material B is obtained as the following equation (3). It is done.
η ₁ = α (V _A −V _A0 ) + β (η _B −η _B0 ) + η ₀ (3)

In Formula (3), η ₁ is the viscosity of the slurry having a predetermined solid content rate, η ₀ is the median value of the viscosity of the slurry having the predetermined solid content rate, α is a coefficient related to the DBP oil absorption amount of the powder material P, and β is the paste Coefficient related to viscosity of material B, _VA is DBP oil absorption amount of powder material P for each lot, V _A0 is median value of DBP oil absorption amount of powder material P, η _B is viscosity of paste material B for each lot, η _B0 is the median value of the viscosity of the paste material B. In the case of the above-described embodiment, for example, if η ₀ = 6018, α = 135, β = 1.84, V _A0 = 54, η _B0 = 3700, the viscosity η ₁ of the slurry having a predetermined solid content is set to the powder material. It can be calculated based on the DBP oil absorption _{VA of} P and the viscosity η _B of the paste material B.

The calculation unit 13 thus calculates the viscosity η ₁ of the slurry having a predetermined solid fraction, and then dilutes the slurry having the predetermined solid fraction with the viscosity η ₁ to finally obtain the viscosity of the electrode slurry SL. Is calculated as a target value.

  FIG. 7 is an example of the relationship between the viscosity of a slurry having a predetermined solid content rate (60 wt%) and the solid content rate at a target viscosity (4000 cP). The horizontal axis represents the viscosity of the slurry having a predetermined solid content (60% by weight). The vertical axis represents the solid content rate at the target viscosity (4000 cP). The 10 points on FIG. 7 indicate the solid content rate required to obtain the target viscosity (4000 cP) for the slurry diluted to the predetermined solid content rate (60 wt%) plotted in FIGS. 5 and 6. The results are plotted. The straight line in FIG. 7 is an approximate straight line showing the relationship between the viscosity of a slurry having a predetermined solid content rate (60 wt%) and the solid content rate at a target viscosity (4000 cP), which is obtained from 10 actually measured values. If the viscosity of the slurry having a predetermined solid content (60% by weight) is x and the solid content at the target viscosity (4000 cP) is y, then y = −0.00066x + 625.4694.

From this result, an equation for calculating the solid content necessary for obtaining the electrode slurry having the target viscosity based on the viscosity η ₁ of the slurry having the predetermined solid content is obtained as the following equation (4). It is done.
M = −γ (η ₁ −η) + M ₁ (4)

In the formula (4), M is a solid fraction necessary for obtaining a slurry for an electrode having a target viscosity, M ₁ is a solid fraction of a slurry having a predetermined solid fraction, and η ₁ is a viscosity of the slurry having a predetermined solid fraction. , Η is a target viscosity of the electrode slurry SL finally obtained, and γ is a coefficient related to the viscosity. In the case of the above-described embodiment, for example, if M ₁ = 60, η = 4000, and γ = 0.00066, the solid content rate required to obtain the electrode slurry with the target viscosity is the viscosity of the slurry with the predetermined solid content rate. It can be calculated based on η ₁ .

By such a method, the calculation unit 13 can calculate the dilution amount (solid content ratio) of the solvent S based on the DBP oil absorption amount V _A of the powder material P and the viscosity η _B of the paste material B.

(Modification)
The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the input receiving unit 11 may be provided with an input device such as a keyboard instead of the reading unit 12, and the operator may input the density of the powder material P or the viscosity of the paste material B using the input device.

  Further, the density of the powder material P or the viscosity of the paste material B received by the input receiving unit 11 may be information for each lot provided by the manufacturer of the powder material P or the paste material B, or the manufacturing apparatus 1. The operator who manufactures the slurry SL for electrodes may be measured.

  An example of a method for measuring the density of the powder material P will be described with reference to FIG. FIG. 8 is a schematic diagram showing an actual measurement process of the density of the powder material P.

  In this method, an operator extracts a part of the powder material P from the lot, and puts the extracted powder material P into the liquid L in which the powder material P is insoluble. When the powder material P is introduced into the liquid L, the liquid level of the liquid L rises from the original liquid level F1 to a new liquid level F2. Based on the rise in the liquid level, the volume of the powder material P is calculated. By dividing the mass of the powder material P charged in the liquid L by the calculated volume, the density of the powder material P can be calculated.

  DESCRIPTION OF SYMBOLS 1 ... Manufacturing apparatus, 11 ... Input reception part, 12 ... Reading part, 13 ... Calculation part, 20 ... Dilution part, B ... Paste material, C ... Information code, P ... Powder material, S ... Solvent, SL ... For electrodes slurry.

Claims (3)

An apparatus for producing a slurry for an electrode that produces a slurry for an electrode using a raw material and a solvent including a powder material and a paste material,
An input receiving unit that receives at least one of the density of the powder material for each lot of the powder material, the DBP oil absorption amount, and the viscosity of the paste material for each lot of the paste material;
Preliminarily holding a target value of the viscosity of the electrode slurry, based on at least one of the density of the powder material, the DBP oil absorption amount, and the viscosity of the paste material received by the input receiving unit, A calculation unit for calculating a dilution amount of the raw material with the solvent for setting the viscosity of the electrode slurry to the target value;
A dilution unit for preparing the electrode slurry by diluting the raw material with the solvent in the amount of dilution calculated by the calculation unit;
An apparatus for producing an electrode slurry.   The input receiving unit reads an information code indicating at least one of the density of the powder material for each lot of the powder material, the DBP oil absorption amount, and the viscosity of the paste material for each lot of the paste material The apparatus for producing a slurry for an electrode according to claim 1, comprising:   The apparatus for producing an electrode slurry according to claim 1 or 2, wherein the density of the powder material received by the input receiving unit is a tap density.

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