KR20200127791A - Method of building content library of cathode active material, and analyzing method using the same - Google Patents

Abstract

Provided are a method for constructing a composition library of a cathode active material capable of quickly analyzing composition of a real-time transition metal, and/or composition of real-time transition metal and alkali metal in a cathode active material of a secondary battery at low cost, and a method for analyzing a cathode active material using the same. The method for constructing a composition library of a cathode active material may comprise the processes of: forming plasma by irradiating a laser to a sample; measuring a spectral line by light emitted from the plasma; obtaining transition metal peak intensity data of the sample from the spectral line; and constructing a transition metal composition library by linking the transition metal peak intensity data and transition metal composition ratio data obtained in advance of the sample.

Description

A method for constructing a composition library of a positive electrode active material, and a method for analyzing the composition of a positive electrode active material using the same {METHOD OF BUILDING CONTENT LIBRARY OF CATHODE ACTIVE MATERIAL, AND ANALYZING METHOD USING THE SAME}

A method for constructing a composition library of a positive electrode active material, and a method for analyzing the composition of a positive electrode active material using the same.

Recently, interest in the development of eco-friendly energy production technology and energy storage devices has been increasing to cope with problems such as global warming and environmental pollution.

As one of the above examples, lithium secondary batteries have developed into small IT-based technologies such as notebook computers and mobile phones, and their application range is rapidly expanding to mid- to large-sized devices such as electric vehicles, power tools, and electric motorcycles.

As a method of analyzing the specific composition of the positive electrode active material of such a lithium secondary battery, an inductively coupled plasma (ICP) analysis method is mainly used. When using the ICP analysis method, the amount of metals, such as lithium, and transition metals such as nickel, cobalt, and manganese in the positive electrode active material can be analyzed. However, the ICP analysis method has a problem that a high cost is required to analyze the composition of the positive electrode active material, such as a long pretreatment time and a high vacuum state is required.

Accordingly, there is a need to develop an analysis method capable of rapid composition analysis at low cost in order to meet the direction of cost reduction such as diversification of raw materials for secondary batteries, process improvement, and yield improvement.

To provide a method for constructing a composition library of a positive electrode active material that can provide rapid real-time composition analysis results at low cost, and a method for analyzing the composition of a positive electrode active material using the same.

According to an embodiment, a plasma is formed by irradiating a laser to a sample, measuring a spectral line by light emitted from the plasma, obtaining transition metal peak intensity data (data) of the sample from the spectral line, There is provided a method for constructing a composition library of a positive electrode active material, including the process of constructing a transition metal composition library by linking the transition metal peak intensity data and the transition metal composition ratio data already obtained of the sample.

The step consisting of the plasma formation and the spectral line detection process is repeatedly performed at least 100 cycles, and the transition metal peak intensity data is calculated by calculating an average of the transition metal peak intensity information (datum) each obtained from the measured spectral line for each cycle. (data) can be calculated.

From the spectral line, 1 to 6 peaks corresponding to the transition metal to be analyzed are specified in the order of decreasing size from largest to smallest, and the average of the intensities of the specified peaks is calculated to calculate transition metal peak intensity information (datum). can do.

The transition metal peak intensity data may include nickel peak intensity data, cobalt peak intensity data, manganese peak intensity data, or a combination thereof.

The already obtained transition metal composition ratio data may be data obtained using at least one of an Induced Coupled Plasma (ICP) analysis method and a Laser-Induced Breakdown Spectroscopy (LIBS) analysis method.

The transition metal composition ratio data already obtained may include molar ratio data of at least two of nickel, cobalt, and manganese.

The sample may be represented by the following formula (1).

[Formula 1]

Me _a (Ni _x Co _y Mn _z ) Q _b T _d O _2(1-e) (OH) _e

In Formula 1 to Formula 2,

Me is at least one metal selected from Li, Na, K, Rb, Cs,

T is at least one metal selected from Al, Pb, Na, Mg, Fe, Cr, Zn,

Q is one or more nonmetals selected from Group 15 to Group 17 elements,

0≤a≤1.5, 0≤b≤10 ^-3 , 0≤d≤10 ^-3 , 0≤x≤1, 0≤y≤1, 0≤z≤1, x+y+z=1, e Is 0 or 1.

The sample includes a first sample and a second sample having different transition metal composition ratios, and each independently for the first sample and the second sample to form the plasma, measure the spectral line, and obtain the transition metal peak intensity data , And a process of constructing a transition metal composition library of the positive active material may be performed.

The sample may have a pellet shape.

The time from the laser irradiation point to the point of measurement of the spectral line may be greater than 0 and less than or equal to 2 μs.

The plasma formation and the spectral line measurement may be performed in an inert gas atmosphere.

The inert gas may include helium gas.

The alkali metal peak intensity data of the sample is further obtained from the spectral line, and the alkali metal composition library is constructed using the alkali metal peak intensity data and the established transition metal composition library. .

The process of constructing the alkali metal composition library is to specify the transition metal peak intensity data linked with the transition metal composition ratio data (data) already obtained in the transition metal composition library, and the sum of the specified transition metal peak intensity data It may include a process of calculating the ratio of the alkali metal peak intensity data to.

The process of constructing the alkali metal composition library may further include a process of calculating a reference variable (R _{alkali = c} ) by substituting a reference alkali metal composition ratio (C) to the calculated first parameter (R _alkali ). have.

The process of constructing the alkali metal composition library may further include a process of calculating a second parameter (R _alkali / R _{alkali = c} ) by dividing the first parameter (R _alkali ) by the calculated reference parameter. have.

The alkali metal is lithium, and the reference alkali metal composition ratio (C) may be 1.0.

The sample includes a third sample and a fourth sample having different alkali metal composition ratios, and each independently for the third sample and the fourth sample, the plasma formation, the spectral line measurement, and the alkali metal peak intensity data acquisition , And the process of building an alkali metal composition library of the positive electrode active material may be performed.

Meanwhile, as a method of analyzing the composition of the positive electrode active material for which the composition ratio of the transition metal is unknown using the method for constructing the composition library of the positive electrode active material described above,

By irradiating a laser to the positive electrode active material to form a plasma, measuring a spectral line by light emitted from the plasma, and substituting the transition metal peak intensity data of the positive electrode active material obtained from the spectral line into the transition metal composition library There is provided a method for analyzing a composition of a positive electrode active material, including the process of deriving data on a composition ratio of a transition metal of the positive electrode active material.

Alternatively, as a method of analyzing the composition of the positive electrode active material of unknown alkali metal composition ratio by using the above-described method for constructing a composition library of the positive electrode active material,

The positive electrode active material is irradiated with a laser to form a plasma, a spectral line by light emitted from the plasma is measured, and the alkali metal peak intensity data of the positive electrode active material obtained from the spectral line is substituted into the alkali metal composition library, and the There is provided a method for analyzing a composition of a positive electrode active material, including the process of deriving an alkali metal composition ratio of the positive electrode active material.

According to one embodiment, the method of constructing a composition library of a positive electrode active material serves as a basis for quickly analyzing the composition of a positive electrode active material for a secondary battery at low cost in real time, thereby contributing to improving the yield and process of the secondary battery.

1 schematically shows a step consisting of plasma formation and a spectral line measurement process in a method of constructing a cathode active material composition library according to an embodiment,
2 is a graph showing the wavelength-intensity of the measured spectral lines,
3 is a graph showing the wavelength-intensity change of the measured spectral lines according to the time change from the point of time of laser irradiation to the point of measurement of the spectral line,
FIG. 4 is a graph showing the (arithmetic) average value of the atomic percent information (datum) of Ni, Co, and Mn accumulated as the cycle increases while increasing the number of steps performed by plasma formation and spectroscopic measurement to 150 cycles. ,
5 is a graph showing an example in which transition metal peak intensity data and transition metal composition ratio data are linked,
6 is a three-dimensional graph schematically showing an alkali metal composition library constructed from a change in peak intensity according to a molar ratio of an alkali metal (Li) within a composition ratio of a transition metal (Ni, Co, Mn),
7 is a graph showing the yz plane of FIG. 6,
8 is a graph showing the relationship between the molar ratio of lithium and R _Li /R _(Li=1) for various NCM-based lithium compounds.

Hereinafter, embodiments will be described in detail so that those of ordinary skill in the art can easily implement them. However, it may be implemented in various different forms and is not limited to the embodiments described herein.

In the drawings, the thicknesses are enlarged to clearly express various layers and regions. The same reference numerals are assigned to similar parts throughout the specification. When a part of a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the case where the other part is "directly above", but also the case where there is another part in the middle. Conversely, when one part is "directly above" another part, it means that there is no other part in the middle.

As a method of analyzing the composition of existing materials, an Inductively Coupled Plasma (ICP) analysis method is widely used. However, the ICP method requires a pretreatment process because the material must be dissolved over a long period of time, as well as a long pretreatment time. In addition, since the ICP method must be performed under specific pressure conditions such as high vacuum, it is difficult to meet the measurement conditions. Finally, since ICP analysis measures the composition of the pretreated material, it is difficult to grasp the composition of the material to be measured in real time or near real time.

On the other hand, it may be considered to use a laser-induced breakdown spectroscopy (LIBS) analysis method as another method for solving the above-described limitations of the ICP analysis method. In this case, plasma is generated through laser irradiation, and by analyzing the peak intensity, peak area, and peak wavelength of the spectral line by the light emitted from the generated plasma, unlike the ICP analysis method, real-time elements of the material to be measured are not required. It has been found that types, and ratios, etc. can be obtained.

However, the peak intensity, peak area, etc. of the spectral line measured by the LIBS analysis method may appear differently depending on the physical properties of the material to be measured, plasma generation conditions, crystal structure, etc. even if the material is the same. This phenomenon is known as the matrix effect of the LIBS analysis method.

Therefore, as a result of researching a method that can analyze the composition of the material to be measured in real time using the LIBS analysis method, the researchers found that when building a standardized composition library for the material to be measured, the result of real-time composition analysis while minimizing the matrix effect described above. It was found that can be obtained, and the present invention was completed.

A method of constructing a composition library of a positive electrode active material according to an exemplary embodiment may include a process of constructing a composition library of constituents contained in a positive electrode active material sample. The constituents may be metal, or may be a non-metal including elements from Groups 15 to 17 such as carbon, nitrogen, phosphorus, and fluorine.

For example, the sample may be a metal oxide or a metal hydroxide containing at least two or more of nickel, cobalt, manganese and other inevitable impurities.

For example, the sample may be a metal oxide or metal hydroxide containing nickel, cobalt, and manganese and other unavoidable impurities.

For example, the sample may be a raw material for a waste anode containing alkali metal, nickel, cobalt, and manganese and other inevitable impurities, and/or a recycled positive electrode active material, or a recycled positive electrode active material precursor.

For example, the sample may be represented by Formula 1 below.

[Formula 1]

Me _a (Ni _x Co _y Mn _z ) Q _b T _d O _2(1-e) (OH) _e

In Formula 1 to Formula 2,

Me is at least one metal selected from Li, Na, K, Rb, Cs,

T is at least one metal selected from Al, Pb, Na, Mg, Fe, Cr, Zn,

Q is one or more nonmetals selected from Group 15 to Group 17 elements,

0≤a≤1.5, 0≤b≤10 ^-3 , 0≤d≤10 ^-3 , 0≤x≤1, 0≤y≤1, 0≤z≤1, x+y+z=1, e Is 0 or 1.

The constituents that make up Formula 1 are as follows, respectively.

Among the above constituents, Me is an alkali metal that plays a role of a carrier in a secondary battery, or a combination thereof, specifically Li, Na, K, or a combination thereof, and more specifically, includes Li can do.

Among the constituents, Ni, and/or Co and/or Mn is oxygen (O ₂ , when e=0 in Formula 1) to enable electrochemical activity of the positive electrode active material through insertion and/or removal of the alkali metal. Together, it may constitute a predetermined crystal structure.

The T may be an impurity derived from a material of the positive electrode plate bonded to the positive electrode active material, and Q may be a non-metallic impurity belonging to a group 15 to 17 element.

A method of constructing a composition library of a positive electrode active material according to an embodiment may include at least constructing a composition library of the transition metal.

In this case, the method of constructing a composition library of the positive electrode active material is to form a plasma by irradiating a laser to a sample to be measured, measuring a spectral line by light emitted from the plasma, and measuring a transition metal peak of the sample from the spectral line. It may be performed, including the process of constructing a transition metal composition library by acquiring intensity data and linking the transition metal peak intensity data with the transition metal composition ratio data obtained already of the sample.

FIG. 1 schematically shows a step of forming a plasma and measuring a spectral line in a method of constructing a composition library of a positive active material according to an embodiment, and FIG. 2 is a graph showing the wavelength-intensity of measured spectral lines.

The step according to FIG. 1 may be performed using at least some of the aforementioned LIBS analysis methods. The LIBS analysis method used in one embodiment may include a process of obtaining radiation emitted by a plasma formed by concentrating a strong laser pulse on a sample surface, and measuring a spectral line obtained from the radiation.

In one embodiment, in the plasma formation process, a strong laser pulse is first concentrated on the sample surface for a short moment to cause ablation of the sample surface, through which the sample surface is vaporized, ionized, and atomized to form plasma. During the plasma formation process, a so-called laser-induced material breakdown occurs. The formed plasma diffuses and cools very quickly, and the excited atoms, ions, and molecular components generated in the plasma after cooling transmit radiation (heat, light, or a combination thereof) that characterizes the elemental composition of the material in the vaporized sample. Radiate.

The laser suitable for the purpose of the present invention may use ruby, Nd:YAG as a solid laser, and may use CO ₂ , N ₂ and excimer lasers as gas lasers, but specific types of lasers are not necessarily limited thereto.

The radiated light emitted from the plasma is sent to a detection means such as a photo detector using a light transmission means such as a lens or an optical fiber. Although the detection means is not particularly limited, for example, a charged coupled device or the like may be mentioned.

Thereafter, the light detected by the detection means is spectroscopic using a spectroscopic means such as a spectroscope, so that the spectral line of the radiation emitted from the plasma can be measured. As shown in FIG. 2, the measured spectral line may have a peak corresponding to a specific wavelength region corresponding to a component. In FIG. 2, a specific wavelength region corresponding to the constituent component is a material-specific property and has already been determined. In addition, the number of the specific wavelength region, and/or the intensity of the peak, and/or the number of peaks are different depending on the type of constituent.

The spectroscopy means is not particularly limited, but a multi-channel high-resolution spectrometer may be mentioned, for example.

Meanwhile, the method of constructing a composition library of a positive electrode active material according to an embodiment is a method for minimizing the matrix effect that appears when using the LIBS analysis method, and may be performed by controlling predetermined conditions when performing the step according to FIG. 1.

The predetermined conditions include, for example, the physical state of the sample to be measured, the atmosphere, the energy of the laser to be irradiated, the size of the laser spot on the surface of the sample to be measured, and the time from the point of laser irradiation to the point of detection of the spectral line. (Delay time), etc. are mentioned.

In one embodiment, the physical state of the sample may be a phase, size, shape, or the like of the sample. In one embodiment, a pellet-shaped sample having a solid phase may be used to maintain the strength, shape, and density of the sample at a predetermined level. When the sample has a pellet shape having a solid phase, since the deviation of the detected spectral line compared to the liquid phase and/or powder shape is small, the reliability of the composition library to be constructed can be improved.

In one embodiment, the atmosphere is not particularly limited as long as it does not react with the constituents in the positive electrode active material and can help rapid cooling of the plasma during the step according to FIG. 1, but may be an inert gas atmosphere. .

The inert gas may include, for example, helium, neon, argon, krypton, xenon, radon, or a combination thereof, and may include, for example, helium.

When the step according to FIG. 1 is performed in an inert gas atmosphere, it is possible to suppress unexpected chemical and/or optical reactions of constituents in the positive electrode active material.

For example, when the positive electrode active material contains aluminum, there is a concern that aluminum may self-absorb light emitted from the plasma and amplify itself. However, when the step according to FIG. 1 is performed in an inert gas atmosphere, for example, a helium gas atmosphere, it is possible to reduce the emission time of the emitted light by rapidly cooling the formed plasma, thereby suppressing and/or preventing the self absorption by aluminum. can do.

In one embodiment, the laser energy is not particularly limited as long as the sample surface is energy equal to or higher than a predetermined output required to form a plasma by abrasion by a laser, but is preferably within a range of more than 0 and 25 mJ or less.

The manner in which the sample is ablated by the laser differs depending on the characteristics of the sample, but if the energy of the laser is too small, abrasion does not occur and only the surface is heated, and if too large, only the vaporization process occurs. Thus, when the energy of the laser is in the above range, a laser induced plasma can be formed.

In one embodiment, the size of the laser spot refers to the size of a portion where the laser irradiated to the sample to be measured actually contacts the sample to be measured, and as the size of the laser spot increases, the area of the sample surface that is ablated by the laser increases.

In one embodiment, the size of the laser spot may be variously adjusted under conditions independent of the aforementioned laser energy, or may be expressed as a predetermined parameter in relation to the aforementioned laser energy. In one embodiment the parameter may be expressed, for example, as the laser energy divided by the size of the laser spot.

For example, the sample to be measured may have different appropriate laser energy and/or laser spot size depending on factors such as volume ratio, compound density, loading level, etc. occupied by the positive electrode active material in the sample. Therefore, using the above parameters, the volume ratio of the sample to be measured, Laser irradiation at a precise level is possible considering volume factors according to the density of the composite material and the loading level.

In addition, when the parameters are linked with a transition metal composition library and an alkali metal composition library to be described later, quantitative analysis may be performed on the state of charge of a sample to be measured having a specific parameter.

In one embodiment, the time from the time of laser irradiation to the time of measurement of the spectral line (hereinafter, referred to as a delay time) is a condition related to the kind of measurable components in the sample. Each component in the sample has a different plasma cooling rate. For example, it is known that a group 15 to 17 element such as carbon, nitrogen, phosphorus, fluorine, etc. has a higher plasma cooling rate than other constituents (eg, alkali metal, transition metal, etc.) due to high ionization energy. Accordingly, the delay time can be variously adjusted according to the type of the element to be analyzed in consideration of the presence of the above-described group 15 to 17 element. For example, if you want to analyze all the impurities of the sample by including the above-described group 15 to 17 elements in the analysis target, for example, more than 0 2 μs or less, more than 0 1.5 μs or less, for example, more than 0 1.4 μs Hereinafter, it may be adjusted to more than 0 and not more than 1.3 μs, more than 0 and not more than 1.2 μs, more than 0 and not more than 1.1 μs, for example, more than 0 and less than 1 μs.

Alternatively, a delay time shorter than the above-described delay time, such as more than 0 and 0.5 μs or less, for example, in order to exclude impurities such as the above-described group 15 to 17 element from the analysis object and to more specifically measure the composition of the main metal element of the positive electrode active material. It may be adjusted to more than 0 and not more than 0.4 μs, for example, more than 0 and not more than 0.3 μs, for example, more than 0 and not more than 0.2 μs, for example, more than 0 and not more than 0.1 μs.

3 is a graph showing a change in wavelength-intensity of analyzed spectral lines according to a time change from the time of laser irradiation to the time of analysis of the spectral line. The laser formation and spectroscopic analysis of FIG. 3 were performed in a helium atmosphere.

3, when the delay time is 1 μs and 0.7 μs, the peak intensity of the spectral line is insignificant, but when the delay time is 0.3 μs and 0.1 μs, the peak intensity of the spectral line is 1 μs. , It is confirmed that it appears significantly larger than the case of 0.7 μs.

Considering that the spectral lines of carbon and phosphorus appear over the wavelength range of about 200 nm to 250 nm, and the spectral lines of fluorine appear over the wavelength range of about 650 nm to 800 nm, the delay time is reduced as shown in FIG. If adjusted to 0.5 μs or less, it can be confirmed that the actual composition of the sample can be more accurately measured in consideration of the presence of components included in the sample.

Meanwhile, in an exemplary embodiment, a process of acquiring transition metal peak intensity data of the sample from a spectral line measured using a spectral means may be included.

In one embodiment, the process of obtaining the transition metal peak intensity data includes extracting peaks of a specific wavelength region corresponding to a component (eg, transition metal, alkali metal, or a combination thereof) from the measured spectral line, and It may be performed including a process of obtaining transition metal peak intensity data by processing the intensity of the peaks.

The processing of the extracted peaks is a process of calculating transition metal peak intensity information (datum) by selectively averaging the intensity of the extracted peaks, a process of calculating transition metal peak intensity data by averaging the transition metal peak intensity information, or Combinations of these may be included. The process of processing the extracted peaks can be performed using a computer, a server, or a known calculation means equipped with other calculation functions.

First, the process of selectively averaging the intensity of the peak is as follows.

In one embodiment, the spectral line is different depending on the constituents, but may generally have several peaks. In this case, extracting and calculating all peaks corresponding to the constituent components may cause an error to increase when considering different intensities of each peak.

Accordingly, in one embodiment, peaks corresponding to constituents (eg, transition metals, alkali metals, or a combination thereof) from the spectral line are 1 to 6 peaks in the order of decreasing size from largest to small, for example 2 To 6, for example, 3 to 6, for example 4 to 6, for example 5 to 6, and calculating the average (e.g. arithmetic mean) of the intensity of the specified peaks to calculate the component (e.g., Transition metal, alkali metal, or a combination of these) peak intensity information (datum) can be calculated. However, the process of selectively averaging the intensity of the peak may be omitted depending on the type of constituents.

Next, a method of averaging the transition metal peak intensity information is as follows.

Peak intensity information of constituents (eg, transition metal, alkali metal, or a combination thereof) is the result of performing one cycle of the steps shown in FIG. 1 (plasma formation and emission line analysis) for the sample, as described above. Even if conditions are controlled, errors can occur every step of the way. Therefore, after repeating the above-described steps shown in FIG. 1 for more than a predetermined number of repetitions, the average of the obtained constituents (e.g., transition metal, alkali metal, or a combination thereof) for peak intensity information (datum) By calculating the arithmetic mean), it is possible to derive peak intensity data of components (eg, transition metals, alkali metals, or combinations thereof) having relatively high accuracy.

The component (e.g., transition metal, alkali metal, or a combination thereof) The component (e.g., transition metal, alkali metal, or a combination thereof) used in the peak intensity information averaging method peak intensity information The selective averaging process may be performed, but the average (eg, arithmetic average) of all peaks corresponding to constituents (eg, transition metal, alkali metal, or a combination thereof) may be calculated without the selective averaging process.

The predetermined number of repetitions indicates the accuracy of component (eg, transition metal, alkali metal, or a combination thereof) peak intensity information (eg, peak intensity information of transition metal, alkali metal, non-metal, etc. obtained from a spectral line). It can be variously adjusted to increase, but for example at least 20 cycles or more, for example 30 cycles or more, for example 40 cycles or more, for example 50 cycles or more, for example 60 cycles or more, for example 70 cycles Or more, for example at least 80 cycles, for example at least 90 cycles, for example at least 100 cycles, for example at least 110 cycles, for example at least 120 cycles, for example at least 130 cycles, for example at least 140 cycles , For example, 150 cycles or more can be performed.

By repeating the above steps for at least 100 cycles on the same sample, the average (e.g., arithmetic average) of the peak intensity information (datum) of 100 or more components obtained is calculated to calculate more accurate peak intensity data (data). You can do it.

FIG. 4 is a graph showing the (arithmetic) average value of atomic% data of Ni, Co, and Mn accumulated as the cycle increases while increasing the number of steps performed by plasma formation and spectroscopic measurement to 150 cycles. 4 is a result of performing the above process under conditions of 12.5 mJ laser energy, helium atmosphere, and a delay time of 0.3 μs for a sample found to be Li(Ni _0.693 Co _0.204 Mn _0.103 )O ₂ as a result of ICP measurement.

Referring to FIG. 4, it can be seen that as the cycle increases, the arithmetic average values of the accumulated atomic% data of Ni, Co, and Mn converge to a predetermined atomic %, and specifically, from 100 cycles or more, each of 71 atomic %, It can be seen that the patterns converge to 20 atomic% and 9 atomic%. It can be seen that the value of the converged atomic% is similar to that of the composition obtained using the ICP analysis method within an error range.

Therefore, as shown in FIG. 4, it can be seen that when the steps disclosed in FIG. 1 are repeated at least 100 cycles or more for the same sample, peak intensity data with high accuracy can be obtained in real time.

The component peak intensity data obtained through the above-described processing process may include at least transition metal peak intensity data. In one embodiment, the transition metal peak intensity data may include nickel peak intensity data, cobalt peak intensity data, manganese peak intensity data, or a combination thereof.

Thereafter, the component (eg, transition metal, alkali metal, or a combination thereof) peak intensity data obtained through the above processing process is calculated as the composition ratio of the previously obtained component (eg, transition metal, alkali metal, or a combination thereof) of the sample. Constituent components (eg, transition metal, alkali metal, or a combination thereof) composition library are constructed by interworking with the data.

In one embodiment, the composition ratio data of the already obtained constituents (eg, transition metal, alkali metal, or a combination thereof) is determined by analyzing the sample by Induced Coupled Plasma (ICP) analysis, laser-induced breakdown spectroscopy (Laser- Induced Breakdown Spectroscopy, LIBS) may be composition ratio data obtained as a result of analysis using at least one of the analysis methods.

In one embodiment, it is preferable to use the component composition ratio data obtained by using the ICP analysis method as the component data already obtained in order to verify between the data measured by different measurement methods. However, one embodiment is not necessarily limited thereto.

In one embodiment, the already obtained component composition ratio data may include the already obtained transition metal composition ratio data. For example, the already obtained transition metal composition ratio data may include molar ratio data of at least two of nickel, cobalt, and manganese.

In one embodiment, the linkage between the above-described component peak intensity data and the previously obtained component composition ratio data may include a process of storing the aforementioned component peak intensity data corresponding to the previously obtained component composition ratio data. For example, when the composition ratio of the transition metal already obtained using the ICP analysis method for the sample according to FIG. 4 is Co:Ni:Mn = 0.693:0.204:0.103, the peak intensity of Co to the obtained composition ratio of Co, Ni, Mn The data, the peak intensity data of Ni, and the peak intensity data of Mn may be linked and stored, respectively. The linked data may be stored in a known storage means having a storage function, such as a computer, a server, or an external storage medium.

Meanwhile, in one embodiment, the sample includes a first sample and a second sample having different compositional composition ratios, and each independently for the first sample and the second sample, the plasma formation, the spectral line measurement, the The process of obtaining component peak intensity data and constructing a component composition library of the positive active material may be performed.

For example, by repeating the above-described process for various samples having different transition metal composition ratios, such as NCM111, NCM433, NCM424, NCM523, NCM622, NCM514, NCM811, etc., transition metal peak intensity data for various transition metal composition ratios can be obtained. Interlocked transition metal composition library can be constructed.

5 is a graph showing an example in which transition metal peak intensity data and transition metal composition ratio data are linked.

5 shows nickel obtained by changing x, y, z from 0 to 1, respectively, under the assumption that x+y+z=1 for a sample having a composition ratio known as Li(Ni _x Co _y Mn _z )O ₂ The transition metal composition library was constructed by linking the peak intensity data of each of, cobalt and manganese with the composition ratio, and then the constructed transition metal composition library was output as a graph for nickel and manganese. Other conditions are as follows.

-Laser energy: 12.5 mJ,

-Atmosphere: Helium atmosphere

-Delay time: 0.3 μs

-Plasma formation and emission ray analysis number of repeated trials: 100 cycles

-5 to 6 peak intensities are optionally averaged

5, for each of nickel and manganese, the relative peak intensity data according to the known composition ratio (x-axis) are as recorded in the squares, and the trend line connecting them is exponential or logarithmic, not a straight line. It can be seen that it is a logarithmic curve. In this way, a transition metal composition library can be constructed by linking transition metal peak intensity data for various samples having different transition metal composition ratios.

When using the constructed transition metal composition library, it is possible to analyze the composition of the positive electrode active material in real time by a simple method even if the LIBS analysis method is used.

Specifically, the method of analyzing the composition of the positive electrode active material of which the composition ratio of the transition metal is unknown by using the method of constructing the composition library of the positive electrode active material is to form a plasma by irradiating a laser to the positive electrode active material, and It may be performed including a process of measuring light rays and substituting transition metal peak intensity data of the positive electrode active material obtained from the spectral line into the transition metal composition library to derive the transition metal composition ratio data of the positive electrode active material.

That is, when using a transition metal composition library constructed according to an embodiment, the transition metal peak intensity data of the positive electrode active material of which the composition ratio of the transition metal is not known is simply substituted into the transition metal composition library using a simple measurement method such as LIBS analysis. Just by doing that, it is possible to easily derive real-time transition metal composition ratio data of the positive electrode active material.

Meanwhile, the method for constructing a composition library of the positive active material described above may further include a process of constructing an alkali metal composition library based on the constructed transition metal composition library.

In the case of an alkali metal, for example lithium, which is widely used as a carrier for a secondary battery, the sensitivity to the LIBS analysis method is very high compared to other transition metals, as can be seen in FIG. 2. Specifically, when the LIBS analysis method is applied, the amount of light emitted from the plasma is very sensitive to the change in the content of the alkali metal, and accordingly, the alkali metal peak intensity data obtained even with the change in the content of the alkali metal can be greatly changed. The sensitivity of the alkali metal to the LIBS analysis method may cause errors in the alkali metal peak intensity data.

However, in the method for constructing a composition library of a positive electrode active material according to an embodiment, considering the sensitivity to the LIBS analysis method of the alkali metal, a transition metal composition library of an alkali metal is constructed using the transition metal composition library constructed through the above method. . Therefore, the constructed transition metal composition library of alkali metals significantly reduces the error compared to the case where the transition metal composition library is not referenced, and may exhibit an accuracy consistent with the composition obtained by a known method such as ICP analysis within an error range.

In one embodiment, the process of constructing the alkali metal composition library may include a process of further obtaining alkali metal peak intensity data of the sample from the spectral line.

In the process of acquiring the alkali metal peak intensity data of the sample, the peaks in a specific wavelength region corresponding to the alkali metal are extracted from the measured spectral line, and the intensity of the extracted peaks is calculated as in the above-described transition metal peak intensity data acquisition process. It can be carried out including a process of obtaining the alkali metal peak intensity data by processing.

The processing of the extracted peaks is a process of calculating alkali metal peak intensity information (datum) by selectively averaging the intensity of the extracted peaks as in the above-described transition metal peak intensity data acquisition process, and averaging alkali metal peak intensity information. Transition metal peak intensity data may be calculated, or a combination thereof may be included. Detailed description of each process is the same as described above, and thus will be omitted.

Thereafter, the transition metal peak intensity data linked with the transition metal composition ratio data (data) already obtained is specified, and a first parameter that is the ratio of the alkali metal peak intensity data to the sum of the specified transition metal peak intensity data Perform the process of calculating (R _alkali ).

The first parameter may be expressed by Equation 1 below.

[Equation 1]

R _alkali represents the ratio of the alkali metal peak intensity data to the sum of the specified transition metal peak intensity data, I _transition represents the transition metal peak intensity data, and I _alkali represents the obtained alkali metal peak intensity data.

In one embodiment, a relationship between the transition metal peak intensity data derived from the above-described transition metal composition ratio data and the alkali metal peak intensity data may be defined using the first parameter (R _alkali ).

Meanwhile, in the process of constructing the alkali metal composition library in one embodiment, a reference variable (R _{alkali = c} ) by substituting a reference alkali metal composition ratio (C) to the first parameter (R _alkali ) represented by Equation 1 It may further include a process of calculating.

The reference alkali metal composition ratio (C) is at least more than 0 mol, for example, may be arbitrarily selected within a range of more than 0 mol ratio and not more than 1.5 mol ratio.

In one embodiment, the reference parameter (R _{alkali = c} ) refers to a parameter when the alkali metal composition ratio is fixed to a specific composition ratio (C) in the above-described first parameter (R _alkali ). The reference variable The reference variable (R _{alkali = c} ) has the following significance in detail.

During the process of constructing the composition library of the positive electrode active material, in principle, in order to find out the composition ratio of the alkali metal using the obtained transition metal composition ratio data, in principle, the relationship between the composition ratio data of the transition metal and the composition ratio data of all alkali metals should be checked.

However, the present inventors use an electrochemical method to desorb a predetermined amount (α, where α is the same or less molar ratio than the reference composition ratio C) from the alkali metal composition ratio having the reference composition ratio (C) in the positive electrode active material. If the composition ratio is adjusted such that the (C-α), the reference variable (R _{= alkali c)} to the ratio of the change in aspect (R _{= c- alkali} α) of the reference variable, regardless of the transition metal composition ratio changes in, the composition ratio of the alkali metal I found it dependent only on change.

That is, by calculating the arbitrary ratio of the first parameter (R _alkali) for setting a first reference variable (R _{alkali = c),} as described above, and the reference variable (R _{alkali = c),} the transition metal composition ratio and Can obtain independent "alkali metal peak intensity data according to alkali metal composition ratio change".

Therefore, it is not necessary to build a separate library for all the transition metal composition ratio data for the change pattern according to the above-described reference variable (R _{alkali = c} ) and all alkali metal composition ratios (C), and accordingly, it is possible to build a library more easily and quickly. Do.

As described above, in the process of constructing the alkali metal composition library in one embodiment, the second parameter (R _alkali / R _{alkali = c} ) is divided by dividing the first parameter (R _alkali ) by the calculated reference parameter. It may further include a process of calculating.

That is, the second parameter may be expressed by Equation 2 below.

[Equation 2]

For example, if the alkali metal is lithium and the reference alkali metal composition ratio (C) is 1.0, the reference parameter is expressed as R _{Li = 1.0} , and the second parameter accordingly may be expressed as R _Li / R _{Li = 1.0} . have.

For example, in the case of the first parameter represented by Equation 1, even if the value of the alkali metal satisfies a predetermined composition ratio (C), the R _alkali metal due to the matrix effect of LIBS described above according to the composition ratio of transition metals The values of _=c may be different. Therefore, there is a limitation in constructing all alkali metal composition libraries for different transition metal composition ratios, and it may be difficult to compare/analyze various samples having different transition metal composition ratios in one graph.

However, as described above, the researchers calculated the reference variable by substituting the case where the alkali metal value has a predetermined composition ratio (C) into the first parameter, and using this to calculate the rate of change of the first parameter relative to the reference variable. When expressed as R (that is, to have the relationship of Equation 2 described above), it was found that the second parameter appears to be identical to each other regardless of the type and composition ratio of the transition metal.

That is, in the process of building an alkali metal composition library according to an embodiment, the relationship between the transition metal peak intensity data and the alkali metal peak intensity data is defined using the above-described first parameter, and the reference alkali metal composition ratio (C) is determined. By dividing by the substituted reference variable, it is possible to calculate a second parameter that can express the types and composition ratios of various transition metals in one graph regardless of the matrix effect.

Meanwhile, in one embodiment, the sample includes a third sample and a fourth sample having different alkali metal composition ratios, and each independently for the third sample and the fourth sample, the plasma formation, the spectral line measurement, the Alkali metal peak intensity data may be obtained, and a process of constructing an alkali metal composition library of the positive electrode active material may be performed.

For example, R _Li values according to various lithium composition ratios are calculated by repeating the above process for various samples having the same transition metal composition ratio but different lithium composition ratios, and this is substituted as the case of the reference lithium composition ratio (eg 1.0 mol). Thus, R _{Li = 1.0} values are calculated, and R _{L /} R _{Li = 1.0} can be calculated using this.

The calculated values of R _Li , R _{Li = 1.0} , R _{L /} R _{Li = 1.0} may be stored in a known information storage means having an information storage function, such as a computer, server, and external storage medium, whereby the positive electrode active material Li composition library of can be built.

Hereinafter, an example of the calculation process and analysis method of the above-described first and second parameters will be described with reference to FIGS. 6 to 8.

6 is a three-dimensional graph schematically showing an alkali metal composition library constructed from a change in peak intensity according to a molar ratio of an alkali metal (Li) within a composition ratio of a transition metal (Ni, Co, Mn). In FIG. 6, the x-axis represents the molar ratio of lithium to the total composition ratio of the transition metals (Ni, Co, Mn), the y-axis represents the content ratio of transition metals (Ni, Co, Mn), and the z-axis represents the aforementioned first parameter (R _Li ) respectively.

For example, when the sample is an NCM-based lithium compound as shown in FIG. 6, first, the above-described first parameter may be calculated according to Equation 1-1 below.

[Equation 1-1]

In Equation 1, R _Li represents the ratio of the alkali metal peak intensity data to the sum of the specified transition metal peak intensity data, I _Ni , I _Co , and I _Mg represent the specified nickel, cobalt, and manganese peak intensity data, respectively, I _Li refers to the obtained lithium peak intensity data, respectively.

Thereafter, the case where the molar ratio of lithium is 1.0 is substituted for the first parameter to calculate the reference variable (R _{Li = 1.0} ), and then the second parameter (R _Li / R _{Li = 1.0} ) can be calculated.

7 is a graph showing the yz plane of FIG. 6. In FIG. 7, the y-axis represents the molar ratio of nickel, which is one of the transition metals, to the total transition metal, and the z-axis represents the reference variable (R _{Li =1.0} ) respectively.

Referring to FIG. 7, as the molar ratio of nickel to the total transition metal increases, the reference variable (R _{Li = 1.0} ) shows an outline of a graph of an increasing aspect. The shape of the graph shown in FIG. 7 may vary as the reference lithium composition ratio with respect to the total transition metal composition ratio is changed. For example, the graph outline of FIG. 7 may represent a graph outline on the yz plane intersecting the long sides of each of the three parallel triangles of FIG. 6 as the reference lithium composition ratio gradually decreases from 1.0 mol, and the reference variable accordingly It can be seen that the change pattern of (R _{alkali = 1.0-k} ) is also smaller than the above-described reference variable (R _{Li = 1.0} ).

On the other hand, Figure 7 shows the reference variable (R _{Li = 1.0} ) for the molar ratio of nickel to the entire transition metal, but the graph remodeling shown in Figure 7 shows the molar ratio of cobalt to the entire transition metal or the mole ratio of manganese to the entire transition metal. It is the same even if it is represented by a graph.

8 is a graph showing the relationship between the molar ratio of lithium and R _Li /R _(Li=1) for various NCM-based lithium compounds.

Other conditions for calculating FIG. 8 are as follows.

-Laser energy: 12.5 mJ,

-Atmosphere: Helium atmosphere

-Delay time: 0.3 μs

-Plasma formation and emission line analysis repetitions: 25 cycles

-Selectively average 5 to 6 peak intensities for Ni, Mn and Co and 3 peak intensities for Li

The significance of the second parameter according to an embodiment is that the result of the change in the composition ratio of lithium can be summarized in one formula using the first parameter and the reference parameter, regardless of the composition ratio of the transition metal. Therefore, when the second parameter according to an embodiment is used, as shown in FIG. 8, the distribution of various NCM-based lithium compounds according to the composition ratio of lithium can be expressed in the form of a two-dimensional graph, regardless of the composition ratio of the transition metal.

In addition, referring to FIG. 8, R _Li / R _{(Li = 1)} for various NCM-based lithium compounds is as recorded, and when connecting them with a trend line, it is exponential or logarithmic rather than a straight line. You can predict that it will be a curve.

When constructing an alkali metal composition library using the constructed transition metal composition library as described above, real-time composition analysis of an alkali metal sensitive to the LIBS analysis method can be more easily performed.

Specifically, a method of analyzing the composition of a positive electrode active material with an unknown alkali metal composition ratio using a method of constructing a composition library of a positive electrode active material using a method of constructing a composition library of a positive electrode active material includes forming a plasma by irradiating a laser to the positive electrode active material. And measuring a spectral line by light emitted from the plasma, and substituting the alkali metal peak intensity data of the positive electrode active material obtained from the spectral line into the alkali metal composition library to derive the alkali metal composition ratio of the positive electrode active material. You can do it.

That is, in the case of using an alkali metal composition library constructed according to an embodiment, the alkali metal peak intensity data of the positive electrode active material of which the alkali metal composition ratio obtained by using the LIBS analysis method is unknown can be simply substituted into the alkali metal composition library. It is possible to easily derive real-time alkali metal composition ratio data of the positive electrode active material.

As described above, in the method for constructing a composition library of a positive electrode active material according to an embodiment, a transition metal composition library and/or an alkali metal composition library can be constructed through the above-described process, and when each constructed composition library is used, the composition ratio It is possible to analyze the composition ratio of alkali metals and/or transition metals in real time of various cathode active materials for which are unknown.

Therefore, the composition analysis method using the composition library of the positive electrode active material constructed as described above can be utilized for the composition analysis of the already completed positive electrode active material, as well as the real-time composition analysis of the waste positive electrode raw material and/or recycled positive electrode active material, It may even be used throughout the manufacturing process of a positive electrode active material for a secondary battery.

For example, when used in a manufacturing process of a secondary battery positive electrode active material, for example, a manufacturing process of a secondary battery positive electrode active material using a waste positive electrode raw material, the composition ratio of the components in the waste positive electrode raw material can be grasped in real time. Therefore, it is possible to quickly calculate the amount of precursor that needs to be added to the waste anode material to match the target lithium and/or transition metal composition, and accordingly, the waste anode material is separately dissolved in an acid to create a new precursor. A new positive electrode active material can be manufactured just by adding and firing. Therefore, when the above-described composition analysis method is used, it is possible to improve the yield and process of the secondary battery.

Hereinafter, through verification examples, the LIBS analysis and ICP analysis results of the positive electrode active material of which the composition ratio is unknown using the composition library of the positive electrode active material constructed according to the exemplary embodiment and the error thereof will be compared and described. However, the technical features of the present invention are not limited by the following verification examples.

Verification Example 1: Analysis of the composition of waste anode raw materials using a cathode active material composition library

Waste anode material 1 (obtained from Sungil Hitech) is physically crushed and filtered to prepare waste anode sample 1 in powder form.

LIBS real-time analysis was performed on the prepared waste anode sample 1 under the following conditions to obtain peak intensity data of lithium, nickel, cobalt, and manganese, respectively.

-Laser energy: 12.5 mJ

-Atmosphere: Helium atmosphere

-Delay time: 0.3 μs

-No repetition of plasma formation and emission line analysis

-Selectively average 5 to 6 peak intensities for Ni, Mn and Co and 3 peak intensities for Li

Thereafter, the obtained lithium, nickel, cobalt, and manganese peak intensity data were substituted into the transition metal composition library and the alkali metal composition library of the positive electrode active material constructed through the above method to derive the composition ratio of lithium, nickel, cobalt, and manganese. And the results are shown in Table 1.

Meanwhile, the composition ratio of lithium, nickel, cobalt, and manganese was determined by performing ICP analysis using an ICP-MS inductively coupled plasma mass spectrometer (Perkin-Elmer, NexION 350D) on the solution of the above-described waste anode material 1 in nitric acid. And the results are shown in Table 1 below.

- LIBS ICP error lithium 0.73 0.66 0.07 nickel 35.8 40.5 4.7 cobalt 38.4 33.9 4.5 manganese 25.8 21.3 4.5

Referring to Table 1, it can be seen that the LIBS real-time analysis result using the constituent composition library of the constructed positive electrode active material substantially coincided with the ICP analysis result, and in particular, the error of lithium was very low, less than 0.1.

Considering the fact that the waste anode material further contains various impurities derived from the anode plate in addition to nickel, cobalt, and manganese, the error (about 5) between the results of the real-time LIBS analysis and the results of the ICP analysis is considered to be acceptable.

Verification Example 2: Analysis of the composition of the recycled positive electrode active material extracted from precursor 1

Waste anode material 2 (obtained from Sungil Hitech) with a different initial composition ratio of lithium, nickel, cobalt, and manganese from the aforementioned waste anode material 1 was subjected to the same method as in Verification Example 1 to prepare waste anode powder. . By forcibly desorbing lithium from the prepared waste anode powder using a chemical reaction, a waste anode sample 2 having a molar ratio of lithium close to zero was prepared.

Thereafter, after dissolving the prepared waste anode sample 2 in nitric acid, the composition ratio of lithium, nickel, cobalt, and manganese of the waste anode sample 2 is derived by performing ICP analysis on the solution through the same procedure as in Verification Example 1 described above.

Based on the composition ratio of lithium, nickel, cobalt, and manganese in the derived waste anode sample 2, Ni(OH) ₂ was additionally added to the aforementioned waste anode raw material 2 so that Ni/(Ni+Co+Mn)=0.88. , Physically pulverized and then filtered to prepare precursor 1.

Thereafter, the prepared precursor 1 was subjected to LIBS analysis and ICP analysis in the same manner as in Verification Example 1 described above, and the results are shown in Table 2.

- LIBS ICP error lithium 0.035 0.034 0.001 nickel 89.3 87.8 1.5 cobalt 7.83 10.3 2.47 manganese 2.88 1.89 0.99

Referring to Table 2, the LIBS real-time analysis result using the constituent composition library of the positive electrode active material was very consistent with the ICP analysis result.In particular, the error of lithium was 0.001, and the errors of nickel, cobalt, and manganese were all less than 2.5. From the results of Table 2, it can be seen from the results of Table 2 that when the composition library of the constructed positive active material is used, the composition ratio in real time during the manufacturing process of the positive active material using the LIBS analysis method can be identified.

Verification Example 3: Analysis of the composition of the recycled positive electrode active material extracted from the precursor 2

In place of the waste anode material 2, the same procedure as in Verification Example 2 was used, except that the waste anode material 3 (obtained from Sungil Hitech) was used with a different initial composition ratio of lithium, nickel, cobalt, and manganese from the waste anode material 1 to 2. Then, precursor 2 is prepared.

Thereafter, LIBS and ICP were each performed in the same manner as in Verification Example 1 for the prepared precursor 2, and the results are shown in Table 3.

- LIBS ICP error lithium 0.029 0.034 0.005 nickel 90.5 88.3 2.2 cobalt 6.95 10.3 3.35 manganese 2.58 1.48 1.1

Referring to Table 3, the LIBS real-time analysis result using the constituent composition library of the positive active material was very consistent with the analysis result by ICP, and it can be seen that it exhibits a similar aspect to that of Verification Example 2.

In addition, from the results of Tables 2 and 3, using a library of constituent components of the positive electrode active material constructed for a high nickel-based positive electrode active material of about 80 atomic% or more and/or a precursor for preparing the same, a relatively accurate real-time using LIBS analysis method It can be seen that the composition ratio can be determined.

Verification Example 4: Analysis of the composition of recycled positive electrode active material

Instead of the waste anode material 3, the waste anode material 4 (obtained from Seongil Hightech) is used, and the target composition ratio between the transition metals is Ni:Co, and the composition ratio of lithium, nickel, cobalt, and manganese is different from that of the waste anode material 1 to 3. :Mn = 70:20:10, except for mixing Ni (OH) ₂ , Mn (OH) ₂ , Co (OH) ₂ in the above-described waste anode raw material 4, the same process as in the above verification example 3 Then, precursor 3 is prepared.

Thereafter, LiOH·H ₂ O is added to the prepared precursor 3 and then calcined at a temperature of 800° C. to 950° C. for 12 hours or more to prepare a recycled positive electrode active material according to Verification Example 4.

Then, the manufactured recycled positive electrode active material For each of the LIBS and ICP were performed in the same manner as in Verification Example 1 described above, the results are shown in Table 4.

- LIBS ICP error lithium 1.04 1.08 0.04 nickel 67.6 70.8 3.2 cobalt 19.2 19.7 0.5 manganese 13.2 9.49 3.71

Referring to Table 4, the LIBS real-time analysis result using the constituent composition library of the constructed positive electrode active material substantially coincided with the ICP analysis result, and the error of lithium was less than 0.05, and the error of nickel, cobalt, and manganese was as low as 4 or less. You can see that it appears.

Therefore, it can be confirmed that the real-time composition analysis of the recycled positive electrode active material is possible by using the constructed library of the composition of the positive electrode active material.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims are also present. It belongs to the scope of the invention.

Claims (20)

The sample is irradiated with a laser to form a plasma,
Measuring a spectral line by light emitted from the plasma,
To obtain transition metal peak intensity data (data) of the sample from the transition metal peak intensity information (datum) obtained from the spectral line,
A method for constructing a composition library of a positive electrode active material, comprising the step of constructing a transition metal composition library by linking the transition metal peak intensity data and the transition metal composition ratio data already obtained of the sample. In claim 1,
The step consisting of the plasma formation and the spectral ray detection process is repeatedly performed at least 20 cycles,
To calculate the transition metal peak intensity data (data) by calculating the average of the transition metal peak intensity information (datum) accumulated as the cycle is repeatedly performed, a method for constructing a composition library of a positive electrode active material. In paragraph 2,
The transition metal peak intensity information (datum),
From the spectral line, 1 to 10 peaks corresponding to the transition metal to be analyzed are specified in the order from the largest to the smallest,
To calculate by calculating the average of the intensities of the specified peaks, a method for constructing a composition library of a positive electrode active material. In claim 1,
The transition metal peak intensity data includes nickel peak intensity data, cobalt peak intensity data, manganese peak intensity data, or a combination thereof, a method for constructing a composition library of a positive electrode active material. In claim 1,
The transition metal composition ratio data already obtained is
Data obtained using at least one of an Induced Coupled Plasma (ICP) analysis method and a Laser-Induced Breakdown Spectroscopy (LIBS) analysis method, a method for constructing a composition library of a positive electrode active material. In claim 1,
The transition metal composition ratio data already obtained is
A method for constructing a composition library of a positive electrode active material, comprising data on a molar ratio of at least two of nickel, cobalt, and manganese. In claim 1,
The sample is represented by the following formula (1), a method for constructing a composition library of a positive active material:
[Formula 1]
Me _a (Ni _x Co _y Mn _z ) Q _b T _d O _2(1-e) (OH) _e
In Formula 1 to Formula 2,
Me is at least one metal selected from Li, Na, K, Rb, Cs,
T is at least one metal selected from Al, Pb, Na, Mg, Fe, Cr, Zn,
Q is one or more nonmetals selected from Group 15 to Group 17 elements,
0≤a≤1.5, 0≤b≤10 ^-3 , 0≤d≤10 ^-3 , 0≤x≤1, 0≤y≤1, 0≤z≤1, x+y+z=1, e Is 0 or 1. In claim 1,
The sample includes a first sample and a second sample having different transition metal composition ratios,
A positive electrode for performing the process of forming the plasma, measuring the spectral line, obtaining the transition metal peak intensity data, and building a transition metal composition library of the positive electrode active material independently for each of the first sample and the second sample How to build an active material composition library. In claim 1,
The sample has a pellet shape, a method for constructing a composition library of a positive electrode active material. In claim 1,
A method for constructing a composition library of a positive electrode active material, wherein the time from the laser irradiation time to the spectral line measurement time is more than 0 and less than or equal to 2 μs. In claim 1,
The plasma formation and the spectral line measurement are performed in an inert gas atmosphere, a method for constructing a composition library of a positive electrode active material. In clause 11,
The inert gas contains helium gas, a method for constructing a composition library of a positive electrode active material. In claim 1,
Further obtaining alkali metal peak intensity data of the sample from the spectral line,
A method for constructing a composition library of a positive electrode active material, further comprising a process of constructing an alkali metal composition library using the alkali metal peak intensity data and the constructed transition metal composition library. In claim 13,
The process of building the alkali metal composition library
Specifying the transition metal peak intensity data linked with the transition metal composition ratio data (data) already obtained in the transition metal composition library,
A method for constructing a composition library of a positive electrode active material comprising a process of calculating a first parameter (R _alkali ), which is a ratio of the alkali metal peak intensity data to the sum of the specified transition metal peak intensity data. In clause 14,
The process of building the alkali metal composition library
A method for constructing a composition library of a positive electrode active material further comprising a process of calculating a reference parameter (R _{alkali = c} ) by substituting a reference alkali metal composition ratio (C) to the calculated first parameter (R _alkali ). In paragraph 15,
The process of building the alkali metal composition library
Dividing the first parameter (R _alkali ) by the calculated reference variable and calculating a second parameter (R _alkali /R _{alkali = c} ). In paragraph 15,
The alkali metal is lithium,
The reference alkali metal composition ratio (C) is 1.0, a method for constructing a composition library of a positive electrode active material. In claim 13,
The sample includes a third sample and a fourth sample having different alkali metal composition ratios,
A positive electrode for performing the process of forming the plasma, measuring the spectral line, obtaining the alkali metal peak intensity data, and building an alkali metal composition library of the positive electrode active material independently for each of the third sample and the fourth sample How to build an active material composition library. A method of analyzing a composition of a positive electrode active material with an unknown transition metal composition ratio using the method for constructing a composition library of a positive electrode active material according to any one of claims 1 to 18,
Forming plasma by irradiating a laser to the positive electrode active material,
Measuring a spectral line by light emitted from the plasma,
Substituting the transition metal peak intensity data of the positive electrode active material obtained from the spectral line into the transition metal composition library to derive the transition metal composition ratio data of the positive electrode active material composition analysis method. A method of analyzing a composition of a positive electrode active material with an unknown alkali metal composition ratio using the method for constructing a composition library of a positive electrode active material according to any one of claims 13 to 18,
Forming plasma by irradiating a laser to the positive electrode active material,
Measuring a spectral line by light emitted from the plasma,
Substituting the alkali metal peak intensity data of the positive electrode active material obtained from the spectral line into the alkali metal composition library to derive the alkali metal composition ratio of the positive electrode active material composition analysis method of the positive electrode active material.

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