Method for adjusting particle size of lithium peroxide and method for producing lithium oxide having adjusted particle size

Abstract

To provide a method for producing lithium oxide, capable of adjusting a particle size and shape of the lithium oxide.SOLUTION: The present invention provides a method for producing lithium oxide using a two-step lithium hydroxide wet conversion method. In a first phase, when the lithium hydroxide is reacted with hydrogen peroxide water to synthesize Li2O2 as an intermediate material, a particle size and shape of the lithium oxide can be controlled in a production process by adjusting a tip speed of an agitator in a reactor. In a second phase, Li2O having the same shape as the intermediate product Li2O2 is synthesized, although a diameter of Li2O2 is reduced by about 10-40% during conversion of the intermediate product Li2O2 into Li2O.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a new method for producing lithium oxide. The degree of the grain size can be controlled during the manufacturing process. This relates to lithium oxide having a controlled degree of oxidation. [Background technology]

[0002] Recently, expensive high-purity lithium oxide (Li 2 O) Synthesis of Lithium-Rich Transition Metal Oxides Used as a raw material. Lithium-rich transition metal oxides are not suitable for lithium-ion batteries. Positive electrode additive for improving reverse capacity (or overvoltage inhibitor), LIC (Lithium ion Highly reactive lithium capacitor and anode material lithiation treatment Lithium-rich metal oxides are made by mixing metal oxides and lithium oxide. After mixing, the mixture is heat-treated in an inert atmosphere to synthesize the material.

[0003] Conventionally, several methods for producing lithium oxide are known. The humidifier is heated to 250℃ or higher in a dry atmosphere. 2 O and CO 2 Adjust the amount of metallic lithium This method has the advantage of being fast, but it is difficult to produce a liquid. Li is adsorbed in the reaction crucible and reacts to produce H 2 O and CO 2 A process of adjusting This has the following disadvantages.

[0004] The method of producing lithium oxide by decomposing lithium hydroxide requires heating at 700°C or higher under vacuum. Lithium hydroxide is decomposed according to the following reaction formula at 200 to 300°C under high or low temperature vacuum. This was decomposed to give liquid lithium hydroxide, which was then decomposed again to give lithium oxide.

[0005] LiOH-H 2 O(s)->LiOH(s);2LiOH(L)->Li 2 O(s)+ H 2 O(g) or 2LiOH(s) -> Li 2 O(s)+H 2 O(g)

[0006] When the reaction is carried out at a temperature of 700°C or higher, the reaction is fast, but the liquid Li is adsorbed in the reaction crucible and CO 2 The disadvantage is that it is difficult to control the When the reaction is carried out at 0°C, a low reaction temperature is required. However, it has the disadvantage that a high degree of vacuum is required.

[0007] The method for producing lithium oxide by the lithium hydroxide wet conversion method is as follows at room temperature: This gave lithium peroxide, which was then decomposed again to give lithium oxide.

[0008] 2LiOH-xH 2 O(s) -> Li 2 O 2 (s);Li 2 O 2 (s) -> Li 2 O( s)+1 / 2O 2 (g)

[0009] This method has the advantage of requiring a low reaction temperature, but 2 O 2 , MeOH, etc. However, the disadvantage is that multiple reagents are required.

[0010] In the method of producing lithium oxide by the lithium carbonate decomposition method, the reaction formula Li 2 CO 3(s)- >Li 2 O(s)+CO 2 (g) Lower PCO 2 At temperatures above 900°C in an atmosphere The reaction proceeds smoothly and the raw material costs are low. However, the reaction rate is slow and it is difficult to use in practice. However, the disadvantage is that high temperatures of over 1200°C are required to achieve this.

[0011] The method for producing lithium oxide by the lithium nitrate decomposition method is as follows: 3 (s)- >Li 2 O(s)+2NO 2 (g) + 1 / 2O 2 (g) React at temperatures above 900°C The advantage is that the reaction rate is fast, but the raw materials are expensive and a NOx removal process is required. This has the following disadvantages.

[0012] The method for producing lithium oxide from metallic lithium, the method for decomposing lithium hydroxide, The lithium decomposition method and the lithium nitrate decomposition method are carried out at temperatures above the melting points of the raw materials. Therefore, lithium oxide is synthesized in the form of giant lumps regardless of the particle size of the raw powder. In order to use it as a raw material for the synthesis of lithium-rich transition metal oxides, The lithium oxide lumps produced need to be crushed and classified. Also, the particle size needs to be adjusted. Therefore, powder loss occurs during the grinding / classification process, and there is a difficulty in having to block the atmosphere. Furthermore, the final particle size of the powders produced in this way is very difficult to control. stomach. Summary of the Invention [Problem to be solved by the invention]

[0013] The present inventors have found that in order to improve the reaction yield in the synthesis reaction, the shape of lithium oxide is spherical and the particle size is small. It is preferable that the diameter distribution is uniform, and it is possible to adjust the average diameter ratio of lithium oxide to metal oxide. It was found that the particle size of the lithium oxide produced was very important. We have developed a method for producing lithium oxide that is processable. [Means for solving the problem]

[0014] In this invention, a two-step lithium hydroxide wet conversion process is used to produce lithium oxide. In the first step, lithium hydroxide is reacted with hydrogen peroxide to produce Li 2 O 2 of In the second step, the synthesized Li 2 O 2 is decomposed at high temperature in an inert atmosphere to produce lithium oxide (Li 2 O). 1st stage: 2LiOH-xH 2 O+H 2 O 2 ->Li 2 O 2 +yH 2 O, x is an integer greater than or equal to 0 number. 2nd stage: Li 2 O 2 ->Li 2 O+1 / 2O 2 (g)

[0015] In the second step, the intermediate product Li 2 O 2 Li 2 Li during conversion to O 2 O 2 The diameter of Although it is reduced by about 40%, the Li has the same shape as the intermediate product. 2 O is synthesized. Therefore, , spherical Li 2 The target diameter of O is Li 2 O 2The particle size of the intermediate material can be controlled. can. [Brief description of the drawings]

[0016] [Figure 1] 1 is a flow chart of a two-step process of the present invention. [Diagram 2] 1 is a SEM photograph of the Li2O2 powder produced according to the present invention. [Diagram 3] 1 shows a graph of the relationship between particle size of Li2O2 produced by the present invention and linear velocity of a reactor. [Figure 4] 1 shows a graph of the relationship between particle size of Li2O2 produced by the present invention and linear velocity of a reactor. [Diagram 5] 1 shows a graph of the relationship between particle size of Li2O2 produced by the present invention and linear velocity of a reactor. [Figure 6] 1 is a SEM photograph of Li2O produced according to the present invention. [Figure 7] 1 shows the XRD result of the Li2O powder produced according to the present invention. [Figure 8] 1 shows the XRD result of the Li2O powder produced according to the present invention. [Figure 9] 1 shows the XRD result of the Li2O powder produced according to the present invention. [Figure 10] 1 shows the XRD result of the Li2O powder produced according to the present invention. [Figure 11] 1 shows a graph of the relationship between particle size of Li2O produced by the present invention and linear velocity of a reactor. [Figure 12] 1 shows a graph of the relationship between particle size of Li2O produced by the present invention and linear velocity of a reactor. [Figure 13] 1 shows a graph of the relationship between particle size of Li2O produced by the present invention and linear velocity of a reactor. [Figure 14] 1 is a SEM photograph of the Li2O powder produced according to the present invention. [Figure 15] 1 is a SEM photograph of the Li2NiO2 powder produced according to the present invention. [Figure 16]FIG. 2 is a charge / discharge relationship diagram of three coin cells manufactured according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] In the present invention, lithium oxide is produced by a two-step lithium hydroxide wet conversion process. In the first step, lithium oxide produces lithium peroxide, which is then decomposed by oxygen in the second step. The lithium oxide particles that are produced have the same shape as the intermediate lithium peroxide particles. The shape of the powder is the same as that of the powder, but the grain size is about 50 to 80%, preferably about 60 to 75%, or more preferably about 50 to 80%. More preferably, the particle size of the lithium peroxide is reduced by about 65 to 70%. The shape, size, particle size, or diameter of lithium oxide can be controlled to obtain a desired shape, size, particle size, or diameter. The diameter can be obtained.

[0018] In the first step, lithium hydroxide dissociates in aqueous solution to produce lithium ions, which It reacts with hydrogen peroxide to produce lithium peroxide (Li 2 O 2 ) and then precipitates. During lithium oxide synthesis, the collision rate and collision energy between the particles are adjusted to produce It is possible to control the particle size of lithium peroxide particles. The collision energy between particles is It changes depending on the internal shape of the vessel, the flow phenomenon of the reactants, the movement speed of the solution, etc. and is the driving force behind this. The TIP VELOCITY of the agitator can be adjusted by defining it as follows: Cut.

[0019] Tip velocity:V_tip=2pi×R_impeller*(RPM) / 60

[0020] The lithium oxide production process of the present invention comprises the following wet reaction of lithium hydroxide as a raw material and an inert atmosphere. It includes a two-step reaction of vapor and high-temperature decomposition. 1st stage: 2LiOH-xH 2 O+H 2 O 2 ->Li 2 O 2 +yH 2 O, x is an integer greater than or equal to 0 number. 2nd stage: Li 2 O 2 ->Li 2 O+1 / 2O 2 (g)

[0021] A flow chart of the two-step process of the present invention is shown in FIG.

[0022] At each stage, atmospheric moisture and CO 2 To prevent contamination by toxic substances and promote material conversion, It is preferred to maintain an active atmosphere.

[0023] 1) Stage 1-1) Mixing of raw materials In this stage, lithium hydroxide monohydrate or a lithium raw material containing lithium hydroxide is mixed with a peroxide. Mix lithium hydroxide and hydrogen peroxide. The theoretical reaction ratio of lithium hydroxide and hydrogen peroxide is: The hydrogen peroxide equivalent ratio is 2:1, but this ratio can be adjusted to improve the reaction yield. The preferred reaction equivalence ratio is 4:1 to 1:1 of lithium hydroxide to hydrogen peroxide. obtain.

[0024] As the starting material, lithium hydroxide monohydrate (LiOH-H 2 O), lithium hydroxide Lithium hydroxide anhydrate (LiOH) or lithium hydroxide polyhydrate (LiOH-xH 2 Use O In order to improve the reaction yield, it is preferable to use anhydrous lithium hydroxide. It is nice.

[0025] Hydrogen peroxide is dissolved in water (H 2 O 2 -zH 2 O, z are integers of 0 or more) can be used. To improve the reaction yield, it is better to use pure hydrogen peroxide, but it is necessary to take into account storage and safety. For all the above reasons it is preferable to use a 35% strength aqueous solution.

[0026] 1-2) Precipitation of intermediate materials and particle size control by reactor impeller agitation Reactor configuration, internal baffles and impeller configuration and dimensions The Li generated can be controlled by adjusting the impeller speed, reactor temperature, etc. 2 O 2 middle The material size can be adjusted. Generally, as the impeller speed increases, the size of the particles increases. The average size decreases and the particles form closer to spherical in shape.

[0027] The higher the reactor temperature, the larger the average particle size becomes and the shape changes from spherical to irregular. The lower the reactor temperature, the smaller the average particle size and the more spherical the particle shape becomes. Change.

[0028] The reaction time is at least 1 minute after the raw materials are added, and preferably 30 to 90 minutes. The temperature does not necessarily need to be adjusted, but it should be within the range of 30 to 60°C in order to adjust the reaction rate. It is preferable to regulate.

[0029] During the synthesis of lithium peroxide, the collision rate and collision energy between the generated particles are adjusted to control the amount of generated It is possible to control the particle size of the lithium peroxide particles. The collision energy between the particles is It varies depending on the internal shape of the reactor, the flow phenomenon of the reactants, the movement speed of the solution, etc. The tip velocity of the agitator is defined as the variable to be adjusted as follows: can be done.

[0030] Tip velocity:V_tip=2pi×R_impeller*(RPM) / 60

[0031] In the above formula, pi means the constant of the circumference of a circle (3.141592...), and R_impellor means the means the radius of the agitator blade and RPM means the revolutions per minute of the agitator blade.

[0032] In the present invention, R_impellor is limited by the reactor shape and the range of motion of the motor. Normally, engineers consider the motor specifications to match the target tip velocity. The value can be determined by:

[0033] In the present invention, the tip speed of the agitator is in the range of 0.2 m / sec. to 20 m / sec., preferably The range is usually 1m / sec. to 10m / sec.

[0034] In the present invention, the tip speed is inversely proportional to the size of the particles produced, which means that the faster the tip speed, the greater the particle size. This means that the particle size can be smaller.

[0035] 1-3) Collection and drying of produced slurry precipitate The impeller in the reactor stirs the intermediate material to produce a slurry. Separate the liquid from the solids by allowing it to settle, passing it through a filter, or by centrifugation. The recovered solution was an aqueous solution of lithium hydroxide in which an excess amount of lithium was dissolved. The recovered Li can be used to produce lithium compounds. 2 O 2 The solids were dried in vacuum. The surface adsorbed water can be dried by this method.

[0036] Li produced in the above step 2 O 2 The particles are nearly or almost spherical, or spherical The particle size of the lithium peroxide produced is in the range of 1 μm to 130 μm, preferably 5 The range is from 50 μm to 50 μm.

[0037] 2) Stage 2-1) Heat treatment in an inert atmosphere The solids produced in step 1) are Li 2 O 2 Inert atmosphere or vacuum atmosphere At high temperatures, Li 2 The conversion temperature is 300° C. or higher, preferably 350° C. to 400° C. The conversion time (reaction time) varies depending on the conversion temperature (reaction temperature). The conversion time and the conversion temperature are inversely proportional. It means that the longer the conversion time, the lower the conversion temperature can be. is 10 minutes or more, preferably 30 minutes or more, even more preferably 1 hour or more, more specifically The conversion time is 30 minutes to 3 hours, or 1 hour to 2 hours. When the conversion temperature is 420°C, the conversion time is 3 0 minutes or more is preferable.

[0038] The particle shape of the lithium oxide produced is lithium peroxide particles, which are intermediate products of step 1. The particle size (particle size, diameter) is about 50 to 80%, preferably The amount of the oxidized carbon generated in this step is reduced to about 60 to 75%, and more preferably to about 65 to 70%. The particle size of lithium oxide is given by the following formula: (Lithium oxide particle size) = a × exp(b × Tip velocity), a and b are the process constant (wherein a and b are engineering constants, 20 <a<60であり、 -0.3 <b<-0.1である) can be determined by

[0039] In the above formula, a is the effect of tip velocity on particle size in terms of energy. This parameter explains the number of collisions and the effect of the tip velocity. The higher the energy, the larger the value. The a value is the number of baffles given to the particle size, and the baffle cutoff It may be a parameter of area effect, and the detailed values ​​are various such as viscosity of the solution, particle size, temperature, etc. The process conditions may vary depending on various factors. The value of a can be determined within the above range.

[0040] b shows the effect of tip velocity on particle size and particle crushing and regrowth activity. A parameter that explains the activation energy. The detailed values ​​depend on the defect energy of the particles, recrystallization energy, etc. This can vary depending on a variety of factors, such as the concentration of, temperature, type of material, and impurity content. A person skilled in the art can determine the b value within the above range by taking into account such process conditions. do.

[0041] 2-2) Li 2 O Powder Collection and Packaging Converted Li 2 O is nitrogen-filled and vacuum-packed to prevent atmospheric deterioration. It is possible. Especially Li 2 O is the mixture of atmospheric moisture and CO 2 At the same time, when contacted, lithium hydroxide and Since it can be converted to lithium carbonate, care must be taken when storing it.

[0042] Li produced in the above step 2 O particles are nearly spherical, nearly spherical, or spherical. The particle size of the lithium oxide is in the range of 1 μm to 100 μm, preferably 5 μm to 5 0 μm range.

[0043] Hereinafter, the present invention will be described in more detail with reference to the following examples. The present invention is presented as an example only and is not intended to be limiting of the present invention. is defined solely by the scope of the claims which follow. EXAMPLES

[0044] Example 1 Reagent-grade lithium hydroxide monohydrate (98%, Morita Chemical) 3 kg, hydrogen peroxide solution (Morita Chemical) 3.4 kg of 34.5%) was mixed in the reactor. Inside the reactor, four rectangular baffles were installed. The reactor rotor was constructed with a double structure. The mechanical impeller rotation speed was 150 The reaction was carried out for 1 hour while rotating at ~750 rpm. An ivory-colored slurry of about 1.2 kcal was obtained. g was collected and dried in a cone-type filter equipped with a metal filter. The solids and liquids were separated by passing the wet Li 2 O 2 1.7 kg of powder and aqueous solution 4.7 kg was recovered. Wet Li 2 O 2 Powder was stored in a vacuum drying oven at 130℃ for 3 hours. , dried Li 2 O 2 1.2 kg of powder was recovered. XRD phase analysis showed that Li 2 O 2 9 8.5%, Li 2 CO 3 1.3%, LiOH-H 2 The analysis was O 0.2%. Li 2 CO 3 is atmospheric CO during transport and XRD measurement. 2 It is presumed to have been generated by

[0045] Recovered Li 2 O 2 The SEM photograph of the powder is shown in Figure 2. As shown, as the RPM increased, the particle size decreased. Average particle size D50 is about 50±20μm at 150rpm, about 30±15μm at 500rpm, and about 750rpm. It was measured to be about 20±10 μm.

[0046] Example 2 Reagent-grade lithium hydroxide monohydrate (98%, Morita Chemical) 5.2 kg, hydrogen peroxide solution (Morita Chemical, 34.5%) 6.0 kg was mixed in the reactor. Inside the reactor, four rectangular batches were placed. The reactor rotor was constructed with a double structure. The mechanical impeller rotation speed was 1 The mixture was allowed to react for 1 hour while rotating at 50 to 750 rpm. An ivory-colored slurry of about 11 .2 kg was collected and a cone-type filter d The solids and liquids were separated by passing the mixture through a ryer. 2 O 2 2.5 kg of powder, and We collected 8.7 kg of wet Li and aqueous solution. 2 O 2 The powder was dried in a vacuum oven at 130°C for 3 hours. After storage for a short time, the dried Li 2 O 2 2.1 kg of powder was recovered. XRD phase analysis showed that Li 2 O 2 98.5%, Li 2 CO 3 1.3%, LiOH-H 2 O was analyzed as 0.2%. .

[0047] Li produced by the synthesis methods of Examples 1 and 2 2 O 2 The particle size and linear velocity of the reactor during the synthesis reaction The relationship is summarized in the table below.

[0048] [Table 1]

[0049] Based on the values ​​in the above table, the Li produced by the synthesis methods of Examples 1 and 2 2 O 2 The grain size and The relationship between the linear velocity of the reactor during the synthesis reaction is shown in the graph of FIG.

[0050] Example 3 Reagent-grade lithium hydroxide monohydrate (98%, Morita Chemical) 30 kg, hydrogen peroxide solution (Morita Chemical) The synthesis reactor contained 4 rectangular baffles. The reactor rotor was constructed with a double structure. The mechanical impeller rotation speed was set at 15 The mixture was allowed to react for 1 hour while rotating at 0 to 500 rpm. An ivory-colored slurry of about 12. 7 kg was collected and a cone-type filter dr with a metal filter attached was used. The solids and liquids were separated by passing the wet Li 2 O 2 14 kg of powder, and water 48 kg of solution was recovered. Wet Li 2 O 2 The powder was stored in a vacuum drying oven at 130°C for 3 hours. After drying, 2 O 2 12.7 kg of powder was recovered. XRD phase analysis showed that Li 2 O 2 The analysis showed it to be over 98.5%.

[0051] Li produced by the synthesis method of Example 3 2 O2 Relationship between particle size and linear velocity of the reactor during synthesis reaction The roles are summarized in the table below.

[0052] [Table 2]

[0053] Based on the values ​​in the above table, the Li produced by the synthesis method of Example 3 2 O 2 Grain size and synthetic reaction The relationship between the time and the linear velocity of the reactor is shown graphically in FIG.

[0054] Analysis of the results of Examples 1 to 3 As a result of analyzing the data from Examples 1 to 3, the tip velocity was determined regardless of the reactor size. ity and Li 2 O 2 It has been found that the average particle size D50 of the powder has the following relationship:

[0055] [Table 3]

[0056] Based on the figures in the table above, Li 2 O 2 The relationship between particle size and linear velocity of the reactor during synthesis reaction is shown in Fig. This is shown in graph 5.

[0057] Example 4-Li 2 O 2 Li 2 Conversion to O Dried Li 2 O 2 10 g of the powder was placed in an alumina crucible and heated to 425°C in a nitrogen atmosphere. The powder was then exposed to the furnace for 7 hours. 2 6.5 g of O was obtained.

[0058] Manufactured Li 2 The shape of the LiO was observed by SEM.2 O's SE The M image shows the shape of a sphere as shown in FIG.

[0059] Dried Li 2 O 2 10 g of the powder was placed in an alumina crucible and heated to 400°C in a nitrogen atmosphere. Expose in furnace for 1 hour and 30 minutes to Li 2 O. A total of 91.2% was converted, with some LiOH The recovered Li 2 O was 6.8g.

[0060] The XRD results of the recovered powder were as shown in FIG.

[0061] Dried Li 2 O 2 10 g of the powder was placed in an alumina crucible and heated to 600°C in a nitrogen atmosphere. Expose in furnace for 1 hour and 30 minutes to Li 2 The recovered Li was converted to O. 2 O was 6.5g. Ta.

[0062] The XRD results of the produced powder are shown in FIG.

[0063] Dried Li 2 O 2 10 g of the powder was placed in an alumina crucible and heated to 700°C in a nitrogen atmosphere. Expose in furnace for 14 hours to Li 2 The recovered Li was converted to O. 2 O was 6.5g.

[0064] Dried Li 2 O 2 10 g of the powder was placed in an alumina crucible and heated to 750°C in a nitrogen atmosphere. Expose to Li in a furnace for 12 hours. 2 The recovered Li was converted to O. 2 O was 6.5g.

[0065] Dried Li 2 O 2 10 g of the powder was placed in an alumina crucible and heated to 425°C in a nitrogen atmosphere. Exposed in a furnace for 3 hours, then exposed at 950°C for 1 hour to Li 2 Converted to O. Li 2 O was 6.5g.

[0066] Dried Li 2 O 2 10 g of the powder was placed in an alumina crucible and heated to 425°C in a nitrogen atmosphere. The Li was then exposed to a furnace for 3 hours and then to 950°C for 2 hours. 2 Converted to O. Li 2 O was 6.5g.

[0067] Dried Li 2 O 2 500 g of the powder was placed in an alumina crucible and then heated to 425°C in a nitrogen atmosphere. Li was exposed to a gas furnace for 3 hours. 2 The recovered powder was 320 g.

[0068] Dried Li 2 O 2 10 g of powder was placed in an alumina crucible and heated in an electric furnace at 600°C for 1 Exposure time 30 minutes Li 2 High purity oxygen (99.98%) 200cc / m The powder was collected in 6 It was .5g.

[0069] The XRD results of the produced powder are shown in FIG.

[0070] Dried Li 2 O 2 10 g of powder was placed in an alumina crucible and heated in an electric furnace at 600°C for 1 Exposure time 30 minutes Li 2High purity oxygen (99.98%) 500cc / m The powder was collected in 6 It was .5g.

[0071] The XRD results of the produced powder are shown in FIG.

[0072] The Li produced in Example 4 2 O 2 and Li 2 Particle size of O and linear velocity of the reactor during synthesis reaction The relationship between the degree is summarized in the table below.

[0073] [Table 4]

[0074] Based on the figures in the table above, Li 2 Figure 1 shows the relationship between the particle size of O and the linear velocity of the reactor during the synthesis reaction. The graph in Figure 13 shows the relationship between tip velocity and lithium oxide. The following equation is obeyed, so the particle size of lithium oxide can be adjusted by adjusting the tip velocity. (Lithium oxide particle size) = a x exp(b x Tip velocity) city), a and b are process constants

[0075] a and b are engineering constants and can be obtained as experimental values ​​using equipment.

[0076] Example 5-Li 2 Synthesis of lithium-rich transition metal oxide using O as raw material 20g of NiO and Li produced 2 Mix 8.85g of O in a small mixer for 5 minutes. The mixed powder was exposed to a nitrogen atmosphere furnace at 700°C for 12 hours to obtain Li 2 NiO 2 The synthesized powder weighed 28.86 g.

[0077] The shape of the mixture was spherical as shown in Figure 14. In particular, the spherical shape shown in Figure 14 Lithium ion implanted on the NIO surface 2 It was confirmed that the O derivatives were uniformly distributed.

[0078] Li synthesized after heat treatment at high temperature 2 NiO 2 The shape of the was as shown in FIG. As shown in Fig. 15, a spherical Li 2 NiO 2 is formed, and unreacted NiO and Li 2 O is observed I couldn't.

[0079] Manufactured Li 2 NiO 2 CR2032 coin cells are manufactured using The characteristics were evaluated. The electrodes were coated on a 14 mm thick aluminum sheet. The thickness of the coating layer was 50-80 μm.

[0080] The electrode slurry is Li 2 NiO 2 :Denka Black (DB): PvdF = 85:10 The electrode is vacuum dried and then pressed to give the final coating. The thickness of the coating layer was 40 to 60 μm. The electrolyte was LiP in EC:EMC=1:2 solvent. F 6 The salt was dissolved in an organic solution at a concentration of 1M.

[0081] The manufactured coin cells were tested at 4.25~3.0V with 0.1C-rate and 1% C The cells were charged and discharged in C / CV mode. The charge and discharge curves of the three coin cells are shown in Figure 16.

[0082] A total of three charge / discharge tests were conducted, with each test showing identical results.

[0083] 1 Red: The average electrochemical characteristics of the coin cells are charge capacity 389.88mAh / g and discharge capacity 130.99mAh / g, irreversible capacity 258.88mAh / g, reversible efficiency 33.60% was measured. 2 Green: The average electrochemical characteristics of the coin cells are charge capacity 388.19mAh / g and discharge capacity 130.82mAh / g, irreversible capacity 257.38mAh / g, reversible efficiency 33.70% was measured.

[0084] Example 6 NiO 100g and the newly developed Li 2 Mix 41.2g of O in a small mixer for 10 minutes. The mixed powder was exposed to a nitrogen atmosphere furnace at 700°C for 12 hours to obtain Li 2 NiO 2 The synthesized powder was collected in an amount of 140 g.

[0085] 100g of NiO and Li purchased as a comparison material 2 O 41.2g using a small mixer The mixed powder was exposed to a nitrogen atmosphere furnace at 700°C for 12 hours. Li 2 NiO 2 The synthesized powder was collected in an amount of 140 g.

[0086] The results of particle size analysis of the powder produced are as follows. The grain size increased by 4.1 μm, and both Dmin. and Dmax increased. This is because the LNO synthesis process The product developed was intended to promote the sintering effect.

[0087] [Table 5]

[0088] XRD was measured for phase analysis of the produced powder, and the phase analysis was performed based on the measured results. The results are shown in Table 6 below. As shown in the results, when the developed product was used, the LNO phase fraction It was confirmed that the content of NiO increased by 3.6 wt%, and the content of residual NiO decreased by 2.7 wt%. was created.

[0089] [Table 6]

[0090] The amount of residual lithium in the powder produced was measured by neutralization titration. The measured LiOH content As shown in Table 7 below, the new product reduced the amount by 58.2%. 2 CO 3 Content depends on air exposure was deemed degenerative.

[0091] [Table 7]

[0092] The recovered powder was used as a raw material to manufacture CR2032 coin cells, and their electrochemical properties were evaluated. The Li produced 2 NiO 2 After induced crushing, it is passed through #325 mesh to remove impurities. The electrodes were coated on 14 mm thick aluminum sheets. The thickness of the coating layer was 50 to 80 μm. The electrode slurry was Li 2 NiO 2 : Denka Black (DB): PvdF = 85:10:5 wt% mixed and manufactured The electrodes are vacuum dried and then pressed, with the final coating thickness being 40-60μm. The electrolyte was LiPF in EC:EMC=1:2 solvent.6 The salt was dissolved at 1M concentration. The manufactured coin cells were charged at 0.1C-rate in the range of 4.25~3.0V. The battery was charged and discharged in CC / CV mode under 1% conditions.

[0093] As a result, the developed product has a charge capacity of 2.7%, a discharge capacity of 3.6%, and an irreversible capacity of 2.2%. The above results show that the LNO synthesis rate has increased due to the development of a new product with improved reaction rate. This was because.

[0094] [Table 8]

[0095] As can be seen from the coin cell manufacturing experiment, the existing Li 2 Synthesis process of LNO compared to O The conversion rate has increased, and the electrochemical capacity has increased, the residual lithium content has decreased, and the material efficiency has increased. I was able to do it.

Claims

1. A method for adjusting the particle size of lithium peroxide produced by a method of producing lithium peroxide by reacting lithium hydroxide hydrate with hydrogen peroxide in a reactor, The lithium peroxide has a spherical shape. The particle size is determined by adjusting the tip speed of the stirrer inside the reactor. The aforementioned chip speed is given by the following formula: V_tip=2pi×R_impeller*(RPM) / 60 (In the above formula, V-tip is the tip speed, Pi is pi, R-impeller is the radius of the agitator blade, and RPM is the rotations per minute of the agitator blade.) Calculated by, The faster the chip speed, the smaller the average size of the lithium peroxide particles generated. A method for adjusting the particle size of lithium peroxide.

2. The method for adjusting the particle size of lithium peroxide according to Claim 1, wherein the particle size of the lithium peroxide produced is in the range of 1 μm to 130 μm.

3. The method for adjusting the particle size of lithium peroxide according to Claim 1, wherein the equivalent ratio of hydrogen peroxide to lithium hydroxide hydrate is 1:4 to 1:

1.

4. The method for adjusting the particle size of lithium peroxide according to Claim 1, wherein the reaction temperature is in the range of 30 to 60°C, and the reaction time is 1 minute or more, or 30 to 90 minutes.

5. (1) A step of producing lithium peroxide by reacting lithium hydroxide hydrate with hydrogen peroxide; and (2) A method for producing lithium oxide with controlled particle size, comprising the step of producing lithium oxide by high-temperature decomposition of the lithium peroxide in an inert atmosphere, In step (1) above, the particle size of lithium peroxide is determined by adjusting the tip speed of the stirrer inside the reactor. The aforementioned chip speed is given by the following formula: V_tip=2pi×R_impeller*(RPM) / 60 (In the above formula, V-tip is the tip speed, Pi is pi, R-impeller is the radius of the agitator blade, and RPM is the rotations per minute of the agitator blade.) Calculated by, The particle size of lithium oxide produced in step (2) above is given by the following formula: (Lithium oxide particle size) = a × exp(b × V - tip), where a and b are process constants (a and b are engineering constants, where 20 < a < 60 and -0.3 < b < -0.1) Determined by, A method for producing lithium oxide with controlled particle size.

6. The manufacturing method according to claim 5, wherein the particle size of the lithium oxide produced in step (2) is 50 to 80% or 60 to 70% of the lithium peroxide particle size produced in step (1).

7. The manufacturing method according to claim 5, wherein the particle size of the lithium oxide produced in step (2) is 60 to 70% of the particle size of the lithium peroxide produced in step (1).

8. The manufacturing method according to claim 5, wherein in step (1), the tip speed of the stirrer inside the reactor is in the range of 0.2 m / sec. to 20 m / sec.

9. The manufacturing method according to claim 5, wherein the size is in the range of 1 μm to 100 μm.

10. The manufacturing method according to claim 5, wherein the size of the generated particles decreases as the chip speed increases.

11. The manufacturing method according to claim 5, wherein the reaction temperature in step (2) is 300°C or higher.

12. The manufacturing method according to claim 5, wherein the reaction time in step (2) is 10 minutes or more, or 30 minutes to 3 hours.

13. A reaction apparatus for adjusting the particle size of lithium peroxide by reacting lithium hydroxide hydrate with hydrogen peroxide, A reactor containing the lithium hydroxide hydrate and the hydrogen peroxide; Multiple baffles installed inside the reactor; A rotor, which is placed inside the reactor and has a double structure; and The rotor includes a stirrer installed on it, The tip speed of the aforementioned agitator is given by the following formula: V_tip=2pi×R_impeller*(RPM) / 60 (In the above formula, V-tip is the tip speed, Pi is pi, R-impeller is the radius of the agitator blade, and RPM is the rotations per minute of the agitator blade.) Calculated by, A reaction apparatus for adjusting the particle size of lithium peroxide, wherein the average size of the lithium peroxide particles produced decreases as the chipping speed increases.

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