JPH10223264A - Deactivating method of used lithium-cobalt secondary battery and cobalt recovering method from used lithium -cobalt secondary battery using the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new variable recovering method, in which a used lithium secondary battery is completely deactivated, dried, heated, crushed, then cobalt variables are physically separated by the difference of particle size and specific gravity or the like, and in addition magnetic property is given to the cobalt variables by a chemical operation, and by utilizing the magnetic property, the cobalt valuables are separated and recovered. SOLUTION: A battery containing cobalt is opened and immersed in a solution, or opened in the solution, and an organic solvent containing an electrolyte in the battery is leached out into the solution. The battery is taken out of the solution, heated, then crushed, and crushed material is sieved, and minus sieve mainly containing cobalt is recovered. Preferably, the crushed material is sieved, that minus sieve has the particle size 5 times or less the maximum particle size of an active material raw material or the crushed active material of the deactivated battery.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for inactivating a used lithium-cobalt secondary battery and a method for recovering cobalt from a used lithium-cobalt secondary battery using the same.

[0002]

2. Description of the Related Art A lithium secondary battery is known as a lightweight and high-capacity battery. For example, lithium cobaltate containing cobalt, which is a valuable metal, is used for the positive electrode active material, and carbon powder is used for the negative electrode active material. Both active materials are mixed with an organic or inorganic binder and N-methyl-2-pyrrolidone as a solvent to form a mixture, and then the positive electrode active material is coated on aluminum foil and the negative electrode active material is coated on copper foil. It becomes a positive electrode and a negative electrode. As a film for separating the positive and negative electrodes, for example, an organic polymer film such as a porous polypropylene film is used. Further, the electrolyte is filled with an organic solvent that does not contain active hydrogen, such as diethyl carbonate and propylene carbonate containing, for example, lithium 6-fluorophosphate, and the positive electrode serves as an aluminum current collector, and the negative electrode serves as a nickel conductor. It is connected and hermetically filled in a metal container mainly composed of iron.

[0003] Deactivate a used lithium secondary battery,
Then, collecting the valuable resources is extremely important from the viewpoint of effective use of resources and prevention of environmental pollution by mere disposal. 6-346160 ". According to the method, (1) the used battery is fired,
(2) crushing, (3) sieving to a specified particle size or less, and separating desired components.

[0004]

However, according to this method, the charged battery is directly baked at a high temperature.
There is a danger of explosion due to evaporation of the internal organic electrolyte and rapid expansion of the internal volume.

If the container of the charged battery is simply opened to avoid this, heat is generated due to a short-circuit current or the like, which is not suitable for actual application. In other words, there are many known methods for recovering valuable resources from used temporary batteries and secondary batteries other than lithium secondary batteries, but even if they are directly applied to used lithium secondary batteries, the safety of operation can be improved. It causes problems from the viewpoints of economy and economy, etc., and is difficult to apply as it is.

On the other hand, a report that a lithium-manganese secondary battery is treated with dilute sulfuric acid and lithium is recovered as a valuable resource [Komazawa et al., Journal of Chemical Engineering, 15, 857 (198)
9) ". However, in this report, the target object was lithium, which did not include cobalt to be recovered according to the present invention.

[0007]

[Purpose] The purpose of the present invention is to physically inactivate a used lithium secondary battery, dry it, heat it, and pulverize it, and then physically separate it according to the difference in particle size and specific gravity. It is an object of the present invention to provide a novel valuable resource recovery method in which magnetism is imparted to cobalt valuables by operation, and the cobalt valuables are separated and recovered using the magnetism.

[0008]

The present invention is configured as described below to achieve the above object. [Battery inactivation step] The organic solvent containing the electrolyte in the battery is leached into the solution by immersing the cobalt-containing battery in the solution after opening the battery or by opening the battery in the solution. It is characterized by the following.

The addition of an electrolyte to the solution in advance has the effect of suppressing the heat generation of the battery, since the discharge proceeds rapidly when the battery has a voltage as described later. The electrolyte to be added is not particularly limited, but it is preferable to use an aqueous solution containing at least one selected from inorganic salts such as sodium chloride, sodium sulfate and ammonium sulfate. It is effective to add 0.001 to 1.0% by weight of the electrolyte.

In order to open a used battery, a fixed or mounted battery is opened by a cutting machine, a crusher, drilling with a drill, piercing a nail, or the like. It is desirable to operate. If the opening is too small, the organic electrolyte in the battery is unlikely to diffuse out of the system from the opening, and the amount of heat stored in the battery is undesirably large. Therefore, in the case of a cylindrical battery, the opening is opened in a direction perpendicular to the columnar portion, and the size of the aperture is 1/1 / the diameter of the battery.
It is preferably 5/4/4, and the opening is desirably penetrated. Immediately after the opening, the opening may be immersed in the solution filled in the discharge vessel or may be immersed in the solution from the beginning.
The solution may be an aqueous solution, a non-aqueous solution or a mixture thereof, but preferably has a large heat capacity and is nonflammable, and water is best in consideration of economy.

An open battery generates heat when left in the air for discharge and ignites organic substances inside, which is dangerous. However, when the battery is thrown into a solution, especially in water, the heat is moderated and the organic solvent containing the electrolyte is removed. , And separate and float on the surface of the aquarium from within the battery. The generation of heat is milder in the presence of the electrolyte than in the case where only the solution is used. However, even in the case where only the solution is used, the heat generation of the battery is moderated by inserting the open battery. This is because lithium salts and the like are eluted from the inside of the battery, resulting in a system containing an electrolyte and a discharge tank becoming a conductive system. That is, the electrolyte containing the electrolyte of the used battery only needs to be mixed into the discharge vessel to some extent without newly preparing an electrolyte. Therefore, the amount of the electrolyte to be added is sufficiently smaller than the amount of the electrolyte required in the ordinary electrolytic reaction. [Heating Step of Deactivated Battery] Next, the deactivated battery obtained in this manner is taken out of the solution, heated and crushed, and the crushed material is sieved under a screen mainly containing cobalt. , But it is also possible to grind before heating.

The inactivated battery is preferably at 200 ° C.
It is obtained by heating to 400 ° C. That is, the main object is to heat the active material binder so as to eliminate or reduce the effect of the active material binder, thereby drying the object and facilitating the pulverizing step. In addition, the polypropylene membrane which is the separation membrane of both electrodes, the organic solvent which has not been removed in the inactivation step of the battery, the electrolyte and the like volatilize or burn,
It is removed by decomposition. The optimal heating temperature depends on the materials used in the battery. Under normal heating conditions, heating below 200 ° C is not sufficient, but most of the materials used in batteries are decomposed below 200 ° C. If this is the case, or if heating is performed under reduced pressure, it is possible to produce an inert battery even with heating at 200 ° C. or lower.

If the heating temperature is set to 400 ° C. or higher, the heating temperature is temporarily set to 400 ° C. due to combustion of organic substances and the like in the battery.
Although the temperature may be higher than or equal to ° C, the rapid oxidation reaction increases the degree of oxidation of the target cobalt valuables, and the subsequent operation of imparting magnetism becomes complicated. Also, when the temperature in the open system is high, when the degree of oxidation of cobalt is high, when aluminum is in the form of an oxide,
In a state where aluminum is completely ionized, the system loses its reducing ability, so that in the step of imparting magnetism to be described later, magnetism cannot be achieved unless aluminum is newly added to the solution. From this, it can be concluded that it is preferable to set the maximum temperature for magnetizing to about 400 ° C.

From the above, the heating temperature is desirably 200 to 400 ° C. for facilitating the pulverizing treatment by volatilization and decomposition of the organic matter and facilitating the provision of magnetism described later. The heating time is appropriately selected depending on the treatment amount and equipment, but in order to achieve the purpose of this step,
It is desirable to heat for about 0.5 to 3 hours.

[Pulverizing and Classifying Process of Inactivated Battery] A battery from which most of organic components and binders are decomposed and removed by this heat treatment is relatively different from a cobalt valuable component which is liable to be powdery. It is composed of an aluminum foil and a copper foil that are hard to be crushed, powdered carbon as a negative electrode active material, an aluminum conductor, a ferromagnetic nickel conductor, and an outer can containing iron as a main component. These pulverizations can be processed by a pulverizer such as a VM mill using a rotating blade.
S Z8801 standard sieve (hereinafter abbreviated as "standard sieve") is screened through a 1 mm sieve to select. The particle size component of about 1 mm or more on the sieve obtained here is mainly composed of aluminum foil, copper foil, and a piece of an outer can mainly composed of iron, and hardly contains cobalt valuables. Therefore, components under about 1 mm below the sieve are further selected by a standard sieve of 250 μm, and components on the standard sieve of 250 μm are again processed by a VM mill and selected by a standard sieve of 250 μm. The obtained component under the standard sieve of 250 μm can be used as a raw material in a refining process known as a valuable metal containing cobalt.

Here, the standard sieve 1 mm and the standard sieve 25
The reason why it is preferable to use 0 μm will be described.
At present, the 50% average particle size of carbon powder and other negative electrode active materials and cobalt oxide and other positive electrode active materials of industrially produced lithium secondary batteries is approximately 5 to 50 μm.
m, and the maximum particle size (maximum particle size) is generally 100 ~
200 μm.

However, secondary particles, which are aggregates of a plurality of particles, are generated in the inactivated active material after the battery pulverization due to the heat treatment of the active material or the remaining binder.
In the case where the particle size (particle size) of the cobalt valuables to be recovered includes a large one, or when the particle size of the active material used in the battery is larger than the above, the standard sieve is 1 m as the first step.
It is considered that it is necessary to select a sieve having a mesh size larger than m, and to use a standard sieve having a mesh size larger than 250 μm, for example, a standard sieve having a mesh size of 300 to 500 μm as a second step. Therefore, the size of the standard sieve used in the second step should be less than 5 times the maximum particle size of the active material of the battery or the secondary particles. It is desirable from the viewpoint of efficiently collecting valuable resources. Here, for the measurement of the maximum particle size, the particle size at the time of 90% accumulation by laser diffraction can be adopted.

From the above, as a first step, the standard sieve of 1 mm is pulverized so as to become pieces of aluminum foil, copper foil, and an outer can. By doing so, the cobalt valuables content of the components under the standard sieve of 1 mm increases.

Next, as a second step, the components under the sieve are further converted to components under a standard sieve of 250 μm to become components composed of powdery materials of approximately 350 μm or less, so that cobalt valuables are efficiently recovered. Things.

If the opening of the standard sieve in the first stage is too large, a component containing almost no cobalt valuables on the sieve can be obtained. It is not preferable because it is mixed. Therefore, before the first step, a step of sieving the mesh with a size larger than that of the standard sieve in the first step may be added to efficiently remove substances other than the cobalt valuables.

In order to further increase the cobalt content of the final product obtained by such a mechanical sorting method, after the above-mentioned pulverization, a wind separator (classifier) or a crusher equipped with a blower, for example, a pin mill is used. Processing is more effective.

Copper foil and aluminum foil can be easily separated as relatively large pieces by a pin mill which is a crusher equipped with an air classifier or a blower. With only a VM mill and a sieve treatment, the powdered carbon contained in the valuables is difficult to be separated because the particle size range is almost equal to the cobalt valuables. Carbon powder (specific gravity: 1.5 to 2.
2), as the aluminum foil or copper foil flies far away, as can be seen from cobalt (II) oxide (specific gravity: 6.5), cobalt oxide (III) (specific gravity: 4.3 to 4.9), etc. This is because cobalt valuables have a higher specific gravity than carbon powder, and therefore are likely to fall immediately below, and thus can be easily separated from carbon and the like.

The order of progress of the heating step, pulverization and classification step is not particularly limited. For example, by crushing the inactivated battery with a VM mill and then heating it, it is possible to easily remove organic substances and the like in the battery and shorten the heating time. The crushing device used may be of one type. [Step of Applying Magnetism to Cobalt Valuables] The above-mentioned separated material having an improved content of cobalt valuables by the above pulverization and air classification is used as a raw material in a refining process known as a valuable metal containing cobalt as described above. However, it is possible to further improve the content of the cobalt valuables by reducing the collected cobalt valuables, imparting magnetism to the cobalt valuables, and recovering the cobalt valuables exhibiting magnetism by magnetic force. Is also possible.

Generally, metallic cobalt is a ferromagnetic material,
Neither of the oxides, cobalt (II) oxide and cobalt oxide (II, III), exhibit normal magnetism at ambient temperature. Therefore, by reducing the recovered cobalt valuables in an acid or alkali aqueous solution, magnetism is imparted to the cobalt valuables, and the cobalt valuables exhibiting magnetism are recovered, thereby further increasing the content of the cobalt valuables. It is to improve.

It should be noted that the expression of the magnetism here means that the magnetism can be selected by a magnetic separator. The cobalt valuables separated in the heating step, the pulverizing step, and the classifying step are oxides, and are antiferromagnetic and insensitive to magnets. Therefore, in order to recover the cobalt valuables in this step, first, pieces of the outer can, which are mainly composed of iron, and nickel pieces constituting the conductor are removed by magnetic force in the pulverizing step and the separating step.

Next, in order to magnetize the remaining cobalt valuables that do not show magnetism, it is necessary to reduce them. In this reduction reaction, it seems that cobalt does not need to be completely reduced to a metallic state.

That is, while the cobalt valuables separated by the above-mentioned heating step, pulverizing step, and sieve are immersed in an aqueous alkali solution, for example, an aqueous caustic soda solution, and an amphoteric metal, for example, aluminum is added to this system in powder form, alumina When dissolved as sodium, it generates hydrogen and reduces cobalt oxide. Here, since the battery uses an aluminum foil, it is reduced only by immersing the above-mentioned valuables in an alkaline aqueous solution, for example, a caustic soda aqueous solution without adding aluminum, but by reducing cobalt valuables. For efficient magnetization, aluminum,
In particular, it is desirable to add a powder.

On the other hand, as a system for reducing cobalt valuables, cobalt valuables are immersed in an acid such as an aqueous hydrochloric acid solution.
It is also possible to add zinc or aluminum powder to reduce the cobalt oxide to make it magnetic. However, since cobalt oxide is slightly eluted into this system, it is preferable to add an amphoteric metal to the aqueous alkali solution from the viewpoint of recovery of cobalt valuables.

The thus obtained magnetic cobalt-containing material having magnetic properties is filtered, washed with water, dried, and recovered as a valuable material having an increased cobalt content by a magnetic force, and subjected to a refining process known as a valuable metal containing cobalt. Can be.
In addition, when magnetically separating cobalt valuables, it is not always necessary to carry out in a dry state, but it is also possible to carry out in a state of being dispersed in a solution. In that case, after washing by filtration, it may be dispersed in a solution, separated by magnetic force, dried and adjusted.

In addition to the above-described reduction method in an aqueous solution, for example, cobalt valuables are heated to 500 to 900 ° C. in an inert gas stream, for example, a nitrogen gas stream, or the opening of the battery is made extremely small. Or heat-treated, or covered with carbon powder, fired, and allowed to cool, resulting in magnetism. However, since it becomes necessary to add a heating step after the pulverization and separation steps, in these cases, the temperature at the time of heating the deactivated battery is set to a higher temperature, and magnetism is imparted to the cobalt valuables from the beginning, and thereafter, After increasing the cobalt content by the pulverization and separation steps, the step of imparting magnetism is omitted, and the cobalt valuables that have already developed magnetism are recovered by magnetic force, thereby further improving the content of the cobalt valuables. Becomes possible.

[0031]

According to the above configuration, the present invention operates as follows. That is, the used battery is opened under the controlled condition, and when the battery has a voltage, the battery is also discharged, so that the used battery is easily inactivated.

Further, the deactivated battery is pulverized by a heating step and a pulverizing step, and is separated by wind power, thereby separating and recovering a valuable material having an improved content of cobalt valuable material. Further, by applying a magnetizing treatment to the separated and recovered cobalt valuables, the cobalt valuables are selectively separated and recovered by the magnetic force, and the recovery efficiency is improved.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to examples, but the present invention is not limited to only examples. [Example 1] Opening-discharge test A set of 30 used cylindrical lithium-cobalt batteries having a diameter of 26 mm and a length of 64 mm was tested. The used battery was fixed in water, and a column having a diameter of 10 mm was passed through a columnar portion using a remotely operable drill. The battery was immediately charged into a discharge vessel, and the water temperature and the state of the system after 30 minutes were observed (Table 1).

The amounts of the water for discharge and the aqueous solution of the electrolyte were all 10 L. The electrolyte solution was 10 L of water, (A) no electrolyte, (B) NaCl, (C) Na ₂ SO ₄ , (D) (N)
H ₄₎ respectively ₂ SO ₄ obtained by dissolving a 10 g, and (used by each 5g dissolved e) and Na ₂ SO ₄ and (NH _{4) 2} SO _4. Gas was generated from the opening of the charged battery, and at the same time, oily organic substances having organic odor separated and floated on the surface of the aqueous solution. The generation of gas was intense in the initial stage when a battery opened to a water-only system was introduced, and was severely generated in a battery whose opening did not penetrate the battery. Furthermore, as the number of inputs increased, the evolution of gas gradually became more gradual. The temperature of the system 30 minutes after the completion of the charging of the 30 batteries is the initial water temperature 7
With respect to ° C, the temperature rose as follows, but fell almost to the outside temperature in 2 hours after the introduction. Table 1 shows the effect of adding the electrolyte.

[0035]

[Table 1] [Example 2] Opening-discharge test A solution obtained by adding 0.5 L of the residual solution of (a) described in Example 1 to 50 L of water was used as an electrolyte, and the used battery used in Example 1 was used. 150 opening-discharge tests were performed. The temperature of the system rose to 25 ° C., but no other abnormalities were observed as in Example 1. [Example 3] Opening-discharge test Cylindrical battery used in Example 1 and a length of 50 mm and a width of 32
A rectangular battery having a thickness of 13 mm and a thickness of 13 mm was cooled and opened in the atmosphere. The batteries both generated heat and a gaseous substance was ejected from the opening to determine that the battery was dangerous. Immediately upon exposure to water, gas evolution became mild and the exothermic reaction became mild. Example 4 Heating of Contents of Inactivated Battery Contents of a battery obtained by inactivating a cylindrical lithium-cobalt battery having a diameter of 26 mm and a length of 64 mm using an aqueous NaCl solution according to the method described in Example 1. Only 3 each
A set of 0 pieces is placed in a muffle furnace in an air atmosphere and placed at 200 ° C. to 250 ° C. for 1 hour, 300 ° C. for 1 hour,
Heating was performed at 00 ° C for 1 hour, 500 ° C for 1 hour, and 1000 ° C for 1 hour.

When the heating temperature reaches 250 to 300 ° C.,
Generation of acid gas was observed, and when the temperature reached 400 ° C., a second gas generation was observed. When heated in a single step to a temperature of 400 ° C. or higher, organic substances were ignited, the temperature inside the furnace rose rapidly, and the generation of cracked gas increased. Heating temperature is 6
When the temperature reached 60 ° C. or higher, gas generation was recognized because the aluminum foil in the system was dissolved and scattered.

Therefore, when heating to a temperature of 400 ° C. or more, the temperature program is set to (a) from normal temperature to 300 ° C.
The maximum temperature is reached after executing a stepwise heating program of (b) holding at 300 ° C. for 1 hour, (c) subsequently raising the temperature to 400 ° C., and (d) holding at 400 ° C. for 1 hour. Thus, it was found that it was necessary to control the rapid decomposition of organic substances and the like. According to this operation program,
Even if it is ignited, it is only temporary and there is no operational problem.

When heated and cooled to 400 ° C. or higher in an open furnace as described in Example 4, non-magnetic cobalt valuables and magnetic cobalt valuables are sometimes obtained. . And it discovered that when nonmagnetic cobalt valuables were obtained, it would be difficult to impart magnetism to the cobalt valuables. [Example 5] Heating of deactivated batteries In accordance with the method described in Example 1, ten cylindrical lithium-cobalt batteries each having a diameter of 26 mm and a length of 64 mm prepared using an aqueous NaCl solution were deactivated, and 10 of each were air-conditioned. It was placed in an atmosphere muffle furnace and heated to a maximum temperature of 300 ° C and 400 ° C. Example 4 heating program according to maximum temperature
The temperature raising program described in (a) to (b) or (a) to (d) was used. That is, the temperature is maintained at 200 ° C. to 250 ° C. for 1 hour and the temperature is raised to 300 ° C. and maintained for 1 hour, or the temperature is maintained at 200 ° C. to 250 ° C. for 1 hour, and the temperature is raised to 300 ° C. and maintained for 1 hour. The temperature was raised to ° C. and maintained for 1 hour. In all cases, generation of acidic gas was observed at a furnace temperature of 250 to 300 ° C., but no oxidation reaction such as combustion was observed. Example 6 Pulverization of Heated Material About 30 cells heated at 200 to 250 ° C. prepared in Example 4 were pulverized by a VM mill and fractionated by a standard sieve of 1 mm and 250 μm.
Table 2 shows the results measured with CP (manufactured by Seiko Denshi Kogyo KK).
Shown in In addition, the amount of carbon was boiled for 15 minutes.
The weight of the dried product was taken as the weight. Next, sample N in Table 2
O. 3 was weighed, and the composition of metals and the like after purification by magnetic separation is shown in Table 3. In Table 2, 1mm>A> 250μ
m means that the component A is 250 μm below a 1 mm standard sieve.
It indicates that it is on the m sieve.

[0039]

[Table 2]

[0040]

[Table 3] [Examples 7-1 to 3] Particle size distribution and quality of Co [Example 7-1] 80 used cylindrical batteries (diameter 13 mm, length 64 mm) were opened according to the conditions of Example 1,
After heating at 240 ° C. for 3 hours, the mixture was allowed to cool, and then pulverized by a VM mill and then a vibro mill. The composition obtained by sizing the pulverized product with a standard sieve having a sieve of 2 mm was measured (the measuring method is the same as that in Example 6; the same applies hereinafter). Table 4 shows the results of the above 2 mm sieve (1) and the below 2 mm sieve (2).

[0041]

[Table 4] [Example 7-2] 2 m of the standard sieve obtained in Example 7-1 (2)
Table 5 shows the results obtained by sizing 488 g of the sample under the m sieve with a standard sieve having different openings. A component having a particle size range of 500 μm or less sieved with a standard sieve opening and having a cobalt content of 2
0% or more.

[0042]

[Table 5] Example 7-3 Effect of Wind Separation The sample of Example 7-1 (2) was placed on a pin mill equipped with a blower at the outlet, and a portion having a large specific gravity (a portion collected immediately below the outlet) was collected. The results of the analysis are shown in Table 6. Wind separation increased the cobalt content to 36.8%.

[0043]

[Table 6] [Examples 8-1 and 2-2] Magnetization reaction The cobalt valuables obtained by the operations of Examples 1 and 7-3 did not show magnetism. The present inventors succeeded in expressing magnetism to the outside world by applying the following treatment to the cobalt valuables. Example 8-1 Expression of Magnetization by Alkali Sample Heated to 200 to 250 ° C. in Example 4, 300 ° C.
The sample heated to 400 ° C. and the sample heated to 400 ° C. were crushed by the VM mill used in Example 6, and none of the samples showed magnetism.

When 10 g of this sample was immersed in 100 ml of a 12 to 25% sodium hydroxide aqueous solution, the metallic aluminum present in the system was dissolved, and at this time, hydrogen was generated to reduce cobalt valuables and develop magnetism. In addition, even if the above-mentioned substance which did not express magnetism was heated to 600 ° C. to 1000 ° C., and the heat-treated product was again alkali-treated, no magnetism was exhibited. The amount recovered by magnetic force was 8.2 g. Example 8-2 Expression of Magnetization in Acid Solution 10 g of the sample used in Example 8-1 and ground after heating at 300 ° C. was immersed in a 10% aqueous hydrochloric acid solution or a 13% aqueous sulfuric acid solution to obtain zinc powder. When 0.5 g was added little by little, gas was immediately generated and the cobalt valuables became magnetic. At the same time, cobalt was eluted into the system, and the solution turned pink-violet. The recovered amount by magnetic force was 7.8 g. Example 9 A crucible (crucible) was charged with 10 g of the sample (substance not exhibiting magnetism) heat-treated at 300 ° C. described in Example 8-1.
, And the top was covered with carbon powder, heated for one hour with a burner, and allowed to cool. The sample showed magnetism by this test.

On the other hand, the sample which had been heated and allowed to cool without adding the carbon powder did not show magnetism. [Example 10] Heating of a used battery in an inert gas flow A naturally used battery having a small opening (a diameter of 1/10 of the battery) was heated to 800 ° C for 2 hours in an inert atmosphere. Heated. No organic matter combustion was observed in this system. Next, pulverize with this inactivation battery VM mill,
It was separated under a standard sieve of 1 mm. Table 7 shows the composition of the sample that was pulverized and separated. When 30 g of the separated sample was weighed and sorted by a magnet, 29 g of a magnetic material was obtained.

[0046]

[Table 7]

[0047]

As is apparent from the above, according to the present invention, a used lithium-cobalt secondary battery can be safely and reliably deactivated by discharge, and cobalt valuables can be easily and effectively recovered. You can do it.

That is, a used battery is opened under a controlled condition, and when the battery has a voltage, the battery is also discharged, so that the used battery can be easily deactivated. In addition, after the inactivated battery is pulverized by the heating step and the pulverizing step, it is separated by wind power, whereby a valuable substance having an improved content of cobalt valuable substance can be separated and collected. Further, by performing a process of imparting magnetism to the separated and recovered cobalt valuables, it becomes possible to selectively separate and recover the cobalt valuables by magnetic force, and the recovery efficiency is enhanced, so that the industrial effect is remarkable. .

Claims (8)

[Claims] An organic solvent containing an electrolyte in a battery is leached into a solution by immersing a battery containing cobalt in a solution after opening the battery or by opening the battery in the solution. Used lithium-
A method for inactivating a cobalt secondary battery. 2. The method according to claim 1, wherein an aqueous solution containing at least one selected from sodium chloride, sodium sulfate and ammonium sulfate as an electrolyte is used as the solution. 3. After performing the inactivation according to claim 1 or 2, heating the battery taken out of the solution, pulverizing the battery, sieving the pulverized material, and collecting the material under the sieve. A method for recovering cobalt from used lithium-cobalt secondary batteries. 4. The method for recovering cobalt from a used lithium-cobalt secondary battery according to claim 3, wherein pulverization is performed before heating. 5. The method for recovering cobalt from a used lithium-cobalt secondary battery according to claim 3, wherein the heating is performed so as to eliminate or reduce the effectiveness of the active material binder. 6. The sieving of the pulverized material, wherein the maximum particle size of the active material after the pulverization of the active material or the inactivated battery is 5%.
6. The method for recovering cobalt from a used lithium-cobalt secondary battery according to claim 3, wherein the component is sieved so as to have a content of twice or less. 7. A method of recovering a used lithium-cobalt secondary battery according to claim 3, 4, 5, or 6, wherein cobalt is separated and recovered using wind power. A method for recovering cobalt from used lithium-cobalt secondary batteries. 8. A method for recovering cobalt from a used lithium-cobalt secondary battery according to claim 3, wherein magnetism is imparted to the recovered material, and cobalt is separated and recovered using a magnetic force. A method for recovering cobalt from used lithium-cobalt secondary batteries.