KR102444732B1 - Cathode material and method for manufacturing cathode material - Google Patents

Abstract

The present invention relates to a method for manufacturing a positive electrode material using lithium hydroxide and NCM as raw materials. Specifically, the method includes: a base material forming step (S100) of dissolving lithium hydroxide powder (111) in a solvent (112) to form mixed melt (110) of a slurry state; a precursor mixing step (S200) of mixing a precursor (120) with the mixed melt after the base material forming step; and a sintering step (S300) of heat-treating and drying the precursor after the precursor mixing step.

Description

{Cathode material and method for manufacturing cathode material}

The present invention relates to a method for manufacturing a cathode material using lithium hydroxide and NCM as raw materials.

Patent Inventions 001 to 004 present inventions disclosed prior to application that are technically similar to the present invention.

US 10-1633638 B1 (June 21, 2016) US 10-2043711 B1 (November 06, 2019) US 10-2021-0071853 A (June 16, 2021) US 10-2169707 B1 (October 19, 2020)

The present invention relates to a method for manufacturing a cathode material using lithium hydroxide and NCM as raw materials.

The present invention relates to a method for reproducing a cathode, and specifically, a base material forming step (S100) of dissolving lithium hydroxide powder 111 in a solvent 112 to form a mixed melt 110 in a slurry state; After the base material forming step, a precursor mixing step (S200) of mixing the precursor 120 in the mixed lysate; After the precursor mixing step, a sintering step of heat-treating and drying the precursor (S300); consists of a time-series step including.

The present invention relates to a method for reproducing a cathode, and in the invention presented above, the step of forming a base material includes a solvent input step of supplying a solvent to the mixing chamber 210 (S110); After the solvent injection step, a powder supply step of supplying lithium hydroxide powder to the mixing chamber (S130); A stirring dissolution step (S140) of stirring and dissolving the solvent and the solute by the stirring means (220) during the powder supply step; After the stirring and dissolution step, the discharging step (S170) of discharging the slurried mixed lysate 110 from the mixing chamber; consists of a step further comprising.

The present invention relates to a method for reproducing a cathode, and in the invention presented above, an addition step (S150) of adding a dopant after the grinding step or during the precursor mixing step;

The present invention relates to a method for reproducing a cathode, and in the invention presented above, the precursor mixing step includes a precursor input step (S210) of continuously and uniformly introducing a precursor; It consists of a step including; an application step (S220) of applying the mixed lysate to the surface of the precursor.

The present invention relates to a method for reproducing a cathode, and in the invention presented above, the sintering step includes a primary heat treatment step (S310) of heating the precursor mixture to a set temperature range and set time by a heating furnace (510); After the primary heating step, the secondary heat treatment step (S320) of heating in a set temperature range and a set time; consists of a step including.

The present invention relates to a cathode material, and consists of a cathode material manufactured by the method presented above.

Due to the present invention, it is possible to efficiently prevent a phenomenon in which a part of the lithium hydroxide powder is solidified in the process of storing and transporting raw materials required for manufacturing the cathode material.

In addition, as the ratio in which a plurality of raw materials constituting the cathode material are mixed with each other is maximized, the efficiency of the cathode material finally manufactured may be improved.

1 is a photograph of a mixed solution in which lithium hydroxide powder of the present invention is dissolved in a solvent.
2 is a detailed photograph of the calcined cathode material of the present invention.
Figure 3 is a flow chart of the cathode material manufacturing step of the present invention.

Hereinafter, the most preferred embodiment of the present invention will be described in detail in order to be described in detail enough to be easily practiced by those of ordinary skill in the art to which the present invention pertains.

The numbers cited in the examples below are not limited only to the objects of reference, and may be applied to all examples. An object that exhibits the same purpose and effect as the configuration presented in the embodiment corresponds to an equivalent replacement object. The higher-level concept presented in the examples includes sub-concept objects that are not described.

[Example 1-1] The present invention relates to a method for producing a cathode material, and a base material forming step (S100) of dissolving lithium hydroxide powder 111 in a solvent 112 to form a mixed melt 110 in a slurry state (S100) ; After the base material forming step, a precursor mixing step (S200) of mixing the precursor 120 in the mixed lysate; After the precursor mixing step, a sintering step of heat-treating and drying the precursor (S300); consists of a time-series step including.

[Example 1-2] The present invention relates to a method for producing a cathode material, and in Example 1-1, the precursor powder includes NCM powder.

The present invention (Examples 1-1 and 1-2) relates to a method for manufacturing a cathode material used in a battery of a secondary battery. Conventional cathode materials were produced unit by unit (lot) by a number of separate procedures. Therefore, it was difficult to secure the homogeneity of the product for each unit, and the continuity of production could not be secured.

However, in the present invention, since the cathode material is continuously produced and the production process is simplified, it is possible to secure high productivity and to ensure homogenization of product quality.

Specifically, the procedure is largely composed of a base material forming step, a precursor mixing step, and a firing step. In the base material forming step, lithium hydroxide powder and a solvent are mixed to obtain a viscous mixed melt, and the mixed melt is present in a slurry state. The precursor is added to the mixed lysate and stirred at the same time to apply the mixed lysate to the outside of the precursor.

The mixed lysate applied to the precursor separates the solvent in the sintering step, and as a result, it is possible to secure the precursor mixture 130 in a form in which lithium hydroxide of a certain thickness is coated on the outside of the precursor. The precursor mixture can be secured as a product of the cathode material 140 through the procedure of the firing step.

The precursor of the present invention uses an NCM precursor, which may take various ratios of nickel, cobalt, and manganese as needed.

[Example 2-1] The present invention relates to a method for producing a cathode material, and in Example 1-1, the step of forming a base material includes a solvent input step of supplying a solvent to the mixing chamber 210 (S110); After the solvent injection step, a powder supply step of supplying lithium hydroxide powder to the mixing chamber (S130); A stirring dissolution step (S140) of stirring and dissolving the solvent and the solute by the stirring means (220) during the powder supply step; After the stirring and dissolution step, the discharging step (S170) of discharging the slurried mixed melt 110 from the mixing chamber; consists of a time series step including.

[Example 2-2] The present invention relates to a method for producing a cathode material, and in Example 2-1, after the solvent injection step, a first temperature maintaining step (S120) of maintaining the solvent temperature at a set temperature; a second temperature maintaining step of maintaining the temperature of the mixed melt during the stirring and dissolution step (S150); After the second temperature maintaining step, the viscosity measuring step (S160) of measuring the viscosity of the slurry; consists of a step including.

[Example 2-3] The present invention relates to a method for producing a cathode material, and in Example 2-1, a pulverizing step of pulverizing lithium hydroxide pellets 101 by a pulverizer 310 before the powder supply step. (S131); After the pulverization step, the classifying step (S132) of sorting only the size selected by the classifier 320 of the pulverized lithium hydroxide powder; consists of a step including a step.

[Example 2-4] The present invention relates to a method for producing a cathode material, and in Example 2-1, the pulverizing step includes forming a particle size of lithium hydroxide in a size of 1 to 7 micrometers; do.

[Example 2-5] The present invention relates to a method for producing a cathode material, and in Example 2-1, the solvent is formed of water 112a or an organic solvent 112b.

[Example 2-6] The present invention is an invention for a method for producing a cathode material, and in Example 1-1, the slurry step includes forming the temperature of the solvent at a temperature of 0 to 100 degrees Celsius. .

[Example 2-7] The present invention relates to a method for producing a cathode material, and in Example 2-6, the organic solvent is gasoline, benzene, toluene, butanol, hexane, thinner, methylene chloride, etheracetone, It includes; that is formed with any one selected from hydrogen fluoride.

The present invention (Examples 2-1 to 2-7) embodies the hair regeneration step. The hair regeneration step aims to completely dissolve lithium hydroxide in a solvent.

The base material consists of a solvent and a solute (lithium hydroxide powder). That is, lithium hydroxide powder is dissolved in a solvent to exist in the form of a slurry. Since it is intended for continuous production, it must be dissolved as quickly as possible. To implement this, the distilled water contained in the mixing chamber is maintained at 50 degrees Celsius, lithium hydroxide powder is put into the mixing chamber, and stirred to dissolve it quickly.

Lithium hydroxide powder should be homogeneously dissolved, and undissolved content should not remain. to implement this. The lithium hydroxide powder is pulverized by a pulverizer, and only the size selected by the classifier is put into the mixing chamber. The particle size of the lithium hydroxide powder selected by the classifier is selected to be 1 to 7 micrometers. That is, the size of the particle size implements a critical condition that satisfies the dissolution condition at a temperature of 50 degrees Celsius of distilled water. The solvent may be substituted with an organic solvent other than distilled water, and when dissolved in an organic solvent, the size of the lithium hydroxide powder and the temperature of the solvent may be applied differently.

During the dissolution process, the dissolution temperature must be kept constant in order to minimize the change of the solute (lithium hydroxide powder) due to dissolution. That is, it is preferable that the temperature of the solvent and the solute accommodated in the chamber are kept constant during the input process. Accordingly, the first temperature maintaining step and the second temperature maintaining step are necessary.

The first temperature maintaining step and the second temperature maintaining step are performed by the heating device 230 of the mixing chamber, and the heating device is controlled by the chamber temperature control device 240 .

Lithium hydroxide is supplied in the form of pellets, which must be pulverized to a certain size. It is pulverized to a predetermined size by the pulverizer, and the pulverized lithium hydroxide powder is selected in size by a classifier. The classifier is preferably distinguished by a cyclone classifier. If necessary, it can be substituted with a classifier that exhibits the same purpose and effect.

The mixed melt should be applied to the outer surface of the precursor with a uniform thickness, and thus the mixed melt should maintain a constant viscosity by combustion. To implement this, the viscosity of the mixed melt dissolved by the viscometer 330 is measured in real time, and a constant viscosity is continuously maintained.

The stirring means consists of a stirring shaft 222 driven by a stirring motor 221 and a stirring blade 223 formed on the stirring shaft, and the stirring blade is characterized in that it is formed in plurality.

[Example 3-1] The present invention relates to a method for producing a cathode material, and in Example 2-1, an addition step of adding a dopant (S150) after the pulverization step or during the precursor mixing step (S150). It consists of time-series steps.

[Example 3-2] The present invention relates to a method for producing a cathode material, and in Example 3-1, the dopant is formed of zirconium or alumina; includes.

[Example 3-3] The present invention relates to a method for producing a cathode material, and in Example 3-1, the amount of the dopant is 0.3 to 0.8% by weight based on the total weight of lithium hydroxide and the precursor.

The present invention (Examples 3-1 to 3-3) specifies the addition of a dopant. Addition of a dopant affects the charge/discharge efficiency of the battery. The dopant may be added in the process of producing the mixed lysate or may be added in the process of producing the precursor mixture.

Specifically, the dopant is made of zirconium or alumina, and 0.3 to 0.8% is added based on the weight of lithium hydroxide and the precursor. The normal numerical range has a critical meaning obtained from the result of the charge/discharge test of the finally completed cathode material.

In the dopant input process, the dopant is accommodated in the dopant container 410 , and the received dopant is introduced into the mixing chamber or the heating furnace in an amount set through a fixed-quantity feeder.

[Example 4-1] The present invention relates to a method for producing a cathode material, and in Example 1-1, the precursor mixing step includes a precursor input step (S210) of continuously and uniformly introducing a precursor; It consists of a time-sequential step including; an application step (S220) of applying a mixed lysate to the surface of the precursor.

[Example 4-2] The present invention relates to a method for producing a cathode material, and in Example 4-1, 200 wt% of the precursor is added based on 100 wt% of the base material.

[Example 4-3] The present invention relates to a method for producing a cathode material, and in Example 4-1, a second supply step (S211) of quantitatively supplying a precursor during the precursor input step (S211).

[Example 4-4] The present invention relates to a method for producing a cathode material, and in Example 4-1, after the stirring step, a drying step (S230) in which a drying process is performed simultaneously; includes.

The present invention (Examples 4-1 to 4-4) specifies the precursor mixing step. The precursor mixing step refers to a process in which the precursor in powder form is put into the mixed melt in the form of a slurry and mixed to apply the mixed melt to the surface of the precursor.

A precursor is introduced into the mixing chamber, and a predetermined amount of the injected precursor is continuously supplied. The supplied precursor is stirred and mixed by a stirring means, and the mixed lysate is uniformly applied to the surface of the precursor. The precursor is accommodated in a separate precursor container, and the precursor is supplied to the mixing chamber through a quantitative supply. After the stirring step, when the set time elapses, the solvent is discharged to the outside of the mixing chamber through the drying step.

The precursor is preferably supplied in the same weight ratio or twice the weight ratio of the mixed lysate part, which can ensure a constant coating thickness for the precursor having a particle diameter of 5 to 15 micrometers.

[Example 5-1] The present invention relates to a method for producing a cathode material, and in Example 1-1, in the firing step, the precursor mixture is heated by a heating furnace 510 to a set temperature range and set time. primary heat treatment step (S310); After the primary heating step, the secondary heat treatment step (S320) of heating in a set temperature range and a set time; consists of a step including.

[Example 5-2] The present invention relates to a method for producing a cathode material, and in Example 5-1, during the first heat treatment step and the second heat treatment step, the gas for discharging the gas inside the heating furnace to the outside Discharge step (S330); consists of a step including.

[Example 5-3] The present invention relates to a method for producing a cathode material, and in Example 5-1, during the first heat treatment step and the second heat treatment step, air input for introducing dry air into the heating furnace Step (S340); consists of steps including.

[Example 5-4] The present invention relates to a method for producing a cathode material, and in Example 5-3, before the air input step, a water removal step (S350) of removing moisture in the air; including done in steps

The present invention (Examples 4-1 to 4-4) specifies the firing step. The precursor mixture is produced as a cathode material through a plurality of heat treatment steps. In each of the plurality of heat treatment steps, heat is applied to the precursor mixture for a set temperature and time.

The precursor mixture is moved inside the furnace for continuous production. That is, the heat treatment step is implemented during the moving process.

The movement of the precursor mixture is made by the rotation of the heating furnace itself, the precursor mixture is moved by the rotation of the transfer blade 520 inside the heating furnace, or it is accommodated in a container and can be moved by the conveyor 530 .

When the precursor mixture is moved by the self-rotation of the heating furnace, the deflected surface of the protrusion formed inside the precursor mixture exerts a transport force, and the rotation of the heating furnace induces the rotation of the precursor mixture to enable uniform heat treatment.

When the precursor mixture is moved by the rotation of the transfer blade, the heating furnace is fixed, but the precursor mixture is stirred and transferred by the internal transfer blade. The conveying blade forms a deflected angle, thereby exerting a conveying force.

When the precursor mixture is moved by the conveyor, the precursor mixture is accommodated in the container-shaped heating vessel 531, and is transferred along the conveyor and heated.

During the firing process, the solvent of the mixed lysate applied to the surface of the precursor mixture is evaporated and the lithium hydroxide powder is attached to the surface of the precursor.

Gas is filled inside the heating furnace during the heat treatment step, and the gas must be quickly discharged to the outside. Therefore, the heating furnace forms a vent 540 communicating with the outside.

In addition, a gas of a certain temperature must be supplied into the heating furnace, and the gas may be supplied with pure air or nitrogen gas. The gas supplied from the outside must maintain a constant temperature. Accordingly, it is characterized in that the temperature of the gas is completed and supplied to a set value by the temperature control device 550 .

In order to prevent moisture from being included in the input gas, moisture is removed through the dehumidifier 560 . The firing step is performed at 800 to 900 degrees Celsius, preferably drying at 850 degrees Celsius.

In addition, a separate cooling step may be additionally included, and a separate cooling step may be included after the firing process. The cooling step consists of temperature control of the cathode material transferred through the cooling chamber (610). The cooling chamber may implement a cooling temperature and a cooling time in a set stage.

[Example 6-1] The present invention relates to a cathode material, and a cathode material manufactured by any one of the manufacturing methods selected from the examples presented above is presented.

The present invention is a product invention and is characterized in that it is manufactured by a manufacturing method. There is a specificity about the manufacturing method, and the manufacturing method affects the product.

101: lithium hydroxide pellets 110: mixed lysate
111: lithium hydroxide powder 112: solvent
112a: water 112b: organic solvent
120: precursor 130: precursor mixture
140: cathode material 210: mixing chamber
220: stirring means 221: stirring motor
222: stirring shaft 223: stirring blade
230: heating device 240: chamber temperature control device
310: grinder 320: classifier
330: viscosity measuring instrument 410: doping agent container
510: heating furnace 520: transfer blade
530: conveyor 531: heating vessel
540: vent 550: temperature control device
560: dehumidifier 610: cooling chamber

Claims (6)

In the cathode reproduction method,
a base material forming step (S100) of dissolving lithium hydroxide powder 111 in a solvent 112 to form a mixed lysate 110 in a slurry state;
After the base material forming step (S100), a precursor mixing step (S200) of mixing the precursor 120 in the mixed lysate;
After the precursor mixing step (S200), a firing step (S300) of heat-treating and drying the precursor;
The base material forming step (S100) includes a solvent input step (S110) of supplying a solvent to the mixing chamber 210;
After the solvent input step (S110), a powder supply step (S130) of supplying lithium hydroxide powder to the mixing chamber;
Before the powder supply step (S130), a grinding step (S131) of pulverizing the lithium hydroxide pellets 101 by the grinder 310; After the pulverization step (S131), the classifying step (S132) of sorting only the size selected by the classifier 320 of the pulverized lithium hydroxide powder; includes;
The grinding step (S131) includes forming the particle size of lithium hydroxide to a size of 1 to 7 micrometers;
A stirring dissolution step (S140) of stirring and dissolving the solvent and the solute by the stirring means (220) during the powder supply step (S130);
After the stirring and dissolving step (S140), the discharging step (S170) of discharging the slurried mixed lysate 110 from the mixing chamber;
In the precursor mixing step (S200), an addition step of adding a dopant (S150);
The dopant is formed of zirconium or alumina,
The doping agent is added in an amount of 0.3 to 0.8 wt% based on the total weight of lithium hydroxide and the precursor;
delete delete The method according to claim 1,
The precursor mixing step includes a precursor input step (S210) of continuously and uniformly introducing the precursor;
an application step of applying a mixed lysate to the surface of the precursor (S220);
Anode reproduction method comprising a.
The method according to claim 1,
The firing step is a primary heat treatment step (S310) of heating the precursor mixture to a set temperature range and set time by a heating furnace (510);
After the first heat treatment step (S310), a second heat treatment step (S320) of heating in a set temperature range and a set time; cathode reproduction method comprising a.
In the cathode material,
A cathode material manufactured by any one of claims 1, 4, and 5.

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