Method for recycling waste battery

Abstract

The present invention relates to a method for recycling a waste battery. The method for recycling a waste battery according to an embodiment of the present invention comprises the steps of: preparing an Acidithiobacillus strain; mixing the Acidithiobacillus strain with a waste battery; and obtaining a metal salt from the waste battery.

Description

How to Recycle Waste Batteries

[0001] The present invention relates to a method for recycling waste batteries.

[0002] The increasing use of electronic devices such as electric vehicles and smartphones has led to growing interest in the reuse and recycling of waste batteries. Waste batteries contain heavy metals such as lithium, nickel, cobalt, and lead, as well as hazardous chemicals. If disposed of without proper treatment, they can cause environmental pollution. Furthermore, the metals contained in waste batteries, such as lithium, nickel, and cobalt, possess significant economic value, making their recovery essential.

[0003] Prior art document, Korean Patent Publication No. 10-1149762, discloses a method for recovering valuable metals from a battery pack.

[0004] The purpose of the present invention is to provide a method for recycling waste batteries that can efficiently recover resources such as valuable metals from waste batteries.

[0005] In addition, the metal salt obtained through the present invention can be utilized as a material for manufacturing a precursor for a secondary battery active material.

[0006] Additionally, the present invention is environmentally friendly.

[0007] Additionally, the present invention is economical.

[0008] A method for recycling a waste battery according to an embodiment of the present invention comprises the steps of preparing an Acidithiobacillus strain, mixing the Acidithiobacillus strain with a waste battery, and obtaining a metal salt from the waste battery.

[0009] The step of preparing the above Acidithiobacillus strain may include a step of applying a magnetic field to the above Acidithiobacillus strain.

[0010] The step of obtaining a metal salt from the waste battery may include a step of applying a magnetic field to the Acidithiobacillus strain and the waste battery.

[0011] The step of preparing the above Acidithiobacillus strain may include a step of applying far-infrared rays to the above Acidithiobacillus strain.

[0012] The step of obtaining a metal salt from the waste battery may include a step of applying far-infrared rays to the Acidithiobacillus strain and the waste battery.

[0013] The above Acidithiobacillus strain may include at least one of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans.

[0014] The above-mentioned waste battery includes a positive electrode active material, and the obtained metal salt may include at least one of Li, Al, Ni, and Co.

[0015] A method for producing a precursor for a secondary battery active material according to an embodiment of the present invention comprises the steps of preparing a metal salt and the steps of producing a precursor for a secondary battery active material using the metal salt. Here, the metal salt is a metal salt obtained by the method of claim 1.

[0016] A method for recycling waste batteries according to an embodiment of the present invention can efficiently recover resources such as valuable metals from waste batteries.

[0017] In addition, the metal salt obtained through the present invention can be utilized as a material for manufacturing a precursor for a secondary battery active material.

[0018] Additionally, the present invention is environmentally friendly.

[0019] Additionally, the present invention is economical.

[0020] Figure 1 is a flowchart of a method for recycling waste batteries according to an embodiment of the present invention.

[0021] Hereinafter, preferred embodiments of the present invention will be described with reference to the attached drawings. However, the embodiments of the present invention may be modified in various ways, and the scope of the present invention is not limited to the embodiments described below. Furthermore, the embodiments of the present invention are provided to more fully explain the present invention to those of ordinary skill in the art.

[0022]

[0023] A method for recycling a waste battery according to an embodiment of the present invention comprises the steps of preparing an Acidithiobacillus strain, mixing the Acidithiobacillus strain with a waste battery, and obtaining a metal salt from the waste battery.

[0024]

[0025] In the step of preparing the above Acidithiobacillus strain, the Acidithiobacillus strain is known to be an acid-oxidizing bacterium that grows well in an acidic environment of about pH 1 to 2 and obtains energy by oxidizing minerals such as iron or sulfur. In the present invention, the above Acidithiobacillus strain may include at least one of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. For reference, Acidithiobacillus ferrooxidans has been deposited with the Korea Research Institute of Bioscience and Biotechnology (KCTC) under resource number KCTC 4516, and Acidithiobacillus thiooxidans has been deposited with the Korea Research Institute of Bioscience and Biotechnology (KCTC) under resource number KCTC 4515.

[0026] This step may include culturing the Acidithiobacillus strain. The culturing method in this step may be performed using a general method for culturing the strain in a medium in the relevant field. At this time, it is preferable to treat the pH of the medium to 1 to 3.5 and supply metal salts such as Fe, S, Mg, K, and Ca to the medium due to the characteristics of the Acidithiobacillus strain. In one embodiment, the medium may contain sulfuric acid or sulfate. This allows the culturing to be performed more effectively.

[0027] This step can be performed in a rotary shaker, rotating the medium at 100 to 200 rpm during the incubation period. Additionally, the incubation temperature can be 35°C or lower, preferably 20 to 30°C.

[0028] The conditions for the above cultivation may vary depending on the type of strain. For Acidithiobacillus ferrooxidans, the pH of the medium may be adjusted to 1.5 to 2 and the culture may be conducted for 5 days. For Acidithiobacillus thiooxidans, the pH of the medium may be adjusted to a higher pH of 2.5 to 3.5 and the culture may be conducted for 7 days or more, preferably 20 days or more.

[0029] In one embodiment, this step may include applying a magnetic field to the Acidithiobacillus strain. This may further enhance the metal extraction efficiency of the Acidithiobacillus strain. The method of applying the magnetic field is not particularly limited, and may be performed by applying direct current or alternating current to a solenoid coil or a Helmholtz coil. This step may be performed continuously while culturing the Acidithiobacillus strain. The magnetic field (magnetic flux density) applied in this step may be 100 mT or less, and preferably 1 to 5 mT.

[0030] In another embodiment, this step may include applying far-infrared rays to the Acidithiobacillus strain. This can further enhance the metal extraction efficiency of the Acidithiobacillus strain. The method for applying the far-infrared rays is not particularly limited, and an LED lighting device emitting far-infrared wavelengths (having a peak wavelength of 5 to 15 µm) can be used. This step may be performed continuously while culturing the Acidithiobacillus strain.

[0031]

[0032] Next, a step of mixing the above Acidithiobacillus strain with a spent battery is performed.

[0033] The above-mentioned spent battery is a concept that includes a battery, a crushed battery, a part of the contents of a battery, a positive or negative electrode active material, an electrolyte, etc., and may be in various phases such as a solid, a liquid, a slurry, etc., and may be in the form of crushed particles or powder. The present invention extracts metals using an Acidithiobacillus strain, and is useful regardless of the phase or shape of the spent battery. However, the present invention is more effective in extracting Li, Al, Ni, and Co among the metals contained in the battery, and therefore the spent battery may contain Li, Al, Ni, and Co metals, and preferably may contain a positive electrode active material. In addition, in order to increase the efficiency of the reaction, the spent battery may be in the form of a powder, and most preferably, the positive electrode active material may be separated from a current collector. However, the present invention is not limited thereto.

[0034]

[0035] Next, a step of obtaining a metal salt from the waste battery is performed. This step may include a step of contacting the Acidithiobacillus strain with the waste battery, allowing the Acidithiobacillus strain to extract a metal salt from the waste battery, and a step of recovering the extracted metal salt.

[0036] First, the step of extracting the metal salt can be carried out by bringing the Acidithiobacillus strain into contact with the spent battery in various ways. A culture medium containing the Acidithiobacillus strain can be poured onto the spent battery, or the spent battery can be placed in a medium or culture medium in which the Acidithiobacillus strain has been cultured. At this time, the concentration of the spent battery can be 1 to 5 g / 100 ml relative to the total components contained in the medium.

[0037] This step can be performed under conditions of 20 to 30°C, and the period is not particularly limited.

[0038] In one embodiment, this step may include applying a magnetic field to the Acidithiobacillus strain and the spent battery. This may further enhance the metal salt extraction efficiency of the Acidithiobacillus strain. The method of applying the magnetic field is not particularly limited, and may be performed by applying direct current or alternating current to a solenoid coil or a Helmholtz coil. This step may be performed continuously while extracting the metal. The magnetic field (magnetic flux density) applied in this step may be 100 mT or less, and preferably 1 to 5 mT.

[0039] In another embodiment, this step may include applying far-infrared rays to the Acidithiobacillus strain and the spent battery. This can further enhance the metal salt extraction efficiency of the Acidithiobacillus strain. The method for applying the far-infrared rays is not particularly limited, and an LED lighting device emitting far-infrared wavelengths (having a peak wavelength of 5 to 15 µm) can be used. This step may be performed continuously while extracting the metal salt.

[0040] The metal salt extracted in this step may include at least one of Li, Al, Ni, and Co. In addition, the metal salt may be a sulfate, and may include at least one of LiNaSO4, NiSO4, MnSO4, CoSO4, and Al2(SO4)3.

[0041]

[0042] After the metal salt extraction is completed, a step may be performed to separate and recover the metal salt from the medium or solvent. This step may be performed using various methods used in the relevant field to recover specific metal salts, and is not particularly limited. For example, this step may be performed using electrolytic precipitation, solvent extraction, or other methods.

[0043]

[0044] The metal salt recovered through the present invention can be used as a material for manufacturing a precursor for a positive electrode active material or a negative electrode active material of a secondary battery. For example, if the spent battery used in the present invention is a positive electrode active material, the metal salt recovered through the present invention can be used as a material for manufacturing a precursor for the positive electrode active material.

[0045]

[0046] A method for producing a precursor for a secondary battery active material according to an embodiment of the present invention comprises the steps of preparing a metal salt and the steps of producing a precursor for a secondary battery active material using the metal salt. Here, the metal salt is a metal salt obtained by the method of claim 1.

[0047]

[0048] The step of preparing the above metal salt may include the previously described waste battery recycling method, and the above metal salt is a metal salt obtained by the previously described waste battery recycling method.

[0049]

[0050] The step of preparing a precursor for a secondary battery active material using the above metal salt may be a method commonly used in the relevant field. For example, this step may be performed according to a co-precipitation method. More specifically, this step may include a step of mixing the metal salt with a sulfate and a sodium hydroxide solution. In this step, the sulfate may be at least one of nickel sulfate, manganese sulfate, and cobalt sulfate, and may vary depending on the active material to be prepared. In this step, the pH of the metal salt solution may be adjusted to about 11 using the sodium hydroxide solution, and the reaction may be performed for about 24 hours to produce a metal composite hydroxide. Next, the metal composite hydroxide may be filtered, washed, and dried to prepare a precursor powder. The precursor prepared through this step may have the following chemical formula.

[0051] [Chemical Formula 1]

[0052] [Ni 1-x Co x Mn x ](OH)2

[0053] [Chemical Formula 2]

[0054] [Ni 1-x Co x Al x ](OH)2

[0055]

[0056] Example: Extraction of metals from waste batteries

[0057] Example 1: Spent batteries were prepared by physically separating the positive electrode material (NCA, Lithium Nickel Cobalt Aluminum Oxide, LiNiCoAlO2) powder from coin cell batteries. Acidithiobacillus strain used was Acidithiobacillus ferrooxidans (Resource Number: KCTC 4516) purchased from the Korea Research Institute of Bioscience and Biotechnology (KCTC). For culture, the Acidithiobacillus ferrooxidans was placed in a Erlenmeyer flask with 9K Medium (Medium Contents (g / L): FeSO4·7H2O 44.7, (NH4)2SO4 3.0, K2HPO4 0.5, MgSO4·7H2O 0.5, KCl 0.1, and Ca(NO3)2 0.01) to adjust the initial pH to 1.8. Next, the Erlenmeyer flask was cultured for 5 days at 160 rpm and 25°C in a rotary shaker while irradiating far-infrared rays. Here, the far-infrared rays were irradiated using an LED light having a peak wavelength of 85.61% within the range of 4 to 20 µm. Next, the previously prepared spent battery (positive electrode material powder) was added to the above-mentioned Erlenmeyer flask at a concentration of 3 g / 100 ml, and the metal was extracted for 4 days while rotating at 160 rpm while irradiating with far-infrared rays. The far-infrared rays were irradiated in the same manner as during microbial culture.

[0058]

[0059] Example 2: The same spent battery as in Example 1 was prepared. Acidithiobacillus strain used was Acidithiobacillus thiooxidans (Resource Number: KCTC 4515) purchased from the Korea Research Institute of Bioscience and Biotechnology (KCTC). For cultivation, the Acidithiobacillus thiooxidans was placed in an Erlenmeyer flask using DSM 71 Medium (Medium Contents (g / L): Sulfur 10, (NH4)2SO4 0.5, K2HPO4 0.25, MgSO4·7H2O 0.25, and CaCl2·2H2O 0.02) with an initial pH adjusted to 3.0. Next, the Erlenmeyer flask was cultured for 21 days at 160 rpm and 25°C while applying a magnetic field in a rotary shaker. Here, the magnetic field was a direct current magnetic field of 3 mT (30 Oe) applied using a solenoid coil. Next, the previously prepared spent battery (positive electrode material powder) was added to the Erlenmeyer flask at a concentration of 3 g / 100 ml, and the metal was extracted for 1 day while applying a magnetic field. The magnetic field was applied in the same manner as during microbial culture.

[0060]

[0061] Example 3: The same spent battery as in Example 1 was prepared. The Acidithiobacillus strain was prepared by mixing 3.5 ml each of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans of Examples 1 and 2. For cultivation, the mixed microorganism was placed in a medium (Medium Contents (g / L): Sulfur 5, (NH4)2SO4 4.0, K2HPO4 0.5, MgSO4·7H2O 0.5, KCl 0.1, Ca(NO3)2 0.01, FeSO4·7H2O 22.1 and CaCl2·2H2O 0.13) with an initial pH adjusted to 1.5 and placed in an Erlenmeyer flask. Next, the above-mentioned Erlenmeyer flask was cultured for 7 days at 160 rpm and 25°C while applying a magnetic field in a rotary shaker. Next, the previously prepared spent battery (positive electrode material powder) was added to the Erlenmeyer flask at a concentration of 3 g / 100 ml, and the metal was extracted for 4 days.

[0062]

[0063] Example 4: The same procedure as Example 3 was followed, except that a magnetic field was applied during cultivation and metal extraction. The magnetic field irradiation conditions were the same as in Example 2.

[0064]

[0065] Comparative Example 1: Metal was extracted in the same manner as in Example 1, except that far-infrared rays were not applied in the microbial culture and metal extraction process.

[0066]

[0067] Comparative Example 2: Metals were extracted in the same manner as in Example 2, except that no magnetic field was applied during the microbial culture and metal extraction process and metal extraction was performed for 4 days.

[0068]

[0069] Experimental Example: Measurement of Leached Metal Concentration by Inductively Coupled Plasma Optical Emission Spectroscopy

[0070] The concentration of metals leached from the media from which metal extraction was completed in Examples 1 to 3 and Comparative Examples 1 and 2 was analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). The analysis was performed using an iCAP 7400DUO (manufactured by Thermo Fisher Scientific) with an RF generator of 1150 W, 27.12 MHz, and a wavelength range of 166-847 nm. The analysis results are shown in Table 1 below.

[0071] Distinction ConditionsLi (ppm)Example 1A. Ferro + Far Infrared 185.100Example 2A. Thio + Magnetic Field 834.2Example 3A. Ferro -A. Thio 2065Example 4A. Ferro -A. Thio + Magnetic Field 2212Comparative Example 1A. Ferro 171.200Comparative Example 2A. Thio 451.080

[0072] Referring to Table 1, it can be seen that the yield of Li is high in the examples in which metal extraction was performed under far-infrared or magnetic field conditions. In addition, it can be seen that Examples 3 and 4 in which Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans were used together have significantly higher Li extraction efficiency than other examples and comparative examples.

[0073]

[0074] The present invention is not limited to the above-described embodiments and the attached drawings, but is intended to be defined by the appended claims. Therefore, those skilled in the art will appreciate that various substitutions, modifications, and alterations may be made without departing from the technical spirit of the present invention as defined in the claims, and such modifications are also within the scope of the present invention.

[0075]

[0076]

Claims

1. Step of preparing Acidithiobacillus strain; A step of mixing the above Acidithiobacillus strain with a waste battery, and Comprising a step of obtaining a metal salt from the above-mentioned waste battery, How to recycle used batteries.

2. In paragraph 1, The step of obtaining a metal salt from the waste battery includes a step of applying a magnetic field of 100 mT or less to the Acidithiobacillus strain and the waste battery. How to recycle used batteries.

3. In paragraph 1, The step of obtaining a metal salt from the waste battery includes a step of applying far-infrared rays to the Acidithiobacillus strain and the waste battery. How to recycle used batteries.

4. In paragraph 1, The above Acidithiobacillus strain comprises at least one of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. How to recycle used batteries.

5. In paragraph 1, The above-mentioned waste battery contains a positive electrode active material, The obtained metal salt contains at least one of Li, Al, Ni and Co. How to recycle used batteries.

6. In paragraph 1, The step of preparing the above Acidithiobacillus strain includes a step of culturing at 35°C or lower. How to recycle used batteries.

7. In paragraph 1, The above metal salt can be used as a precursor for manufacturing a positive electrode active material. How to recycle used batteries.

8. Steps for preparing metal salts and It includes a step of manufacturing a precursor for a secondary battery active material using the above metal salt, The above metal salt is a metal salt obtained by the method of claim 1. Method for manufacturing a precursor for a secondary battery active material.

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