JP2012079630A - Recovery method of valuables from lithium ion secondary battery and recovered material having valuables - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recovery method of valuables which can recover the valuables such as cobalt and nickel from a lithium ion secondary battery with high recovery rate as well as an easy process.SOLUTION: A recovery method of valuables from a lithium ion secondary battery comprises: a roasting step to obtain a roasted material by roasting the lithium ion secondary battery at 400°C or higher; a crushing step to obtain a crushed material by hitting and crushing the roasted material; and a screening step to obtain a recovered material where the crushed material is sieved to over-sized material and under-sized material.

Description

  The present invention relates to a valuable product from a lithium ion secondary battery that can recover valuable materials such as cobalt and nickel from a defective product generated in the manufacturing process, equipment used, and a lithium ion secondary battery that is discarded with the life of the battery. The present invention relates to a method for recovering a product, and a recovered product containing a valuable material obtained by the recovery method.

Lithium-ion secondary batteries are lighter, higher-capacity, and higher-electromotive force secondary batteries than conventional lead-acid batteries and nickel-cadmium secondary batteries, and are used as secondary batteries for personal computers, electric vehicles, portable devices, etc. Has been. Valuables such as cobalt and nickel are used for the positive electrode of the lithium ion secondary battery as lithium cobaltate (LiCoO ₂ ), a ternary positive electrode material (LiNi _x Co _y Mn _z O _{2 (x + y + z)} ), and the like. Yes.

  Lithium ion secondary batteries are expected to continue to be used in the future, so defective products generated during the manufacturing process, used equipment, and lithium ion secondary batteries that are discarded due to battery life, etc., cobalt, nickel, etc. From the viewpoint of resource recycling, it is desired to collect valuable resources.

Therefore, as a method of recovering valuable materials, primary lithium secondary batteries are primarily roasted at a temperature of 350 ° C. or higher, then crushed by a shearing type crusher, and then crushed material is sieved, and further, the sieve Secondary roasting, treatment with acid, pH is adjusted to 4-5.5 while blowing oxidizing gas into this treatment liquid, filtration is performed, alkali is added to the filtrate, and the precipitate is recovered by filtration. A method to do this has been proposed (Patent Document 1).
Also proposed is a cobalt recovery method in which used lithium secondary batteries are roasted at a temperature of 350 ° C or higher, then crushed by a shearing crusher, the crushed material is sieved, and the screen is magnetically sorted. (Patent Document 2).
However, in these proposed technologies, in the crushing process, valuable materials such as cobalt and nickel and other metals such as iron are not crushed to a sufficiently separable state in the subsequent screening process. Therefore, valuable materials such as cobalt and nickel remain on the sieve after the sieve selection. As a result, there is a problem that the recovery rate of valuable materials in the recovered material obtained under the sieve is lowered. In addition, since iron etc. are contained on the sieve, it is not economical to collect valuable materials from the sieve because more processes are required. Further, when a shearing type crusher is used, iron with small generated particles is mixed into the recovered material under the sieve. Since both iron and cobalt are magnetically deposited, when the magnetic separation of cobalt is performed after sorting, iron is also collected at the same time, and there is a problem that iron is mixed as an impurity in the collected material.

  Accordingly, there is a need for a method for recovering valuable materials such as cobalt and nickel from a lithium ion secondary battery at a high recovery rate and having a simple process, and a recovered material containing valuable materials obtained by the recovery method. This is the current situation.

JP-A-7-207349 JP 7-245126 A

  An object of the present invention is to solve the above-described problems and achieve the following objects. That is, the present invention includes a valuable material recovery method capable of recovering valuable materials such as cobalt and nickel from a lithium ion secondary battery at a high recovery rate and having a simple process, and a valuable material obtained by the recovery method. The purpose is to provide recovered materials.

Means for solving the problems are as follows. That is,
<1> A roasting step of roasting a lithium ion secondary battery at a roasting temperature of 400 ° C. or higher to obtain a roasted product,
A pulverizing step of pulverizing the roasted product by hitting to obtain a pulverized product;
Sieving the pulverized material into a sieve and a sieve, and a sieve sorting step for obtaining a recovered material containing the valuable material under the sieve. It is a collection method.
<2> The method for recovering valuable materials from the lithium ion secondary battery according to <1>, wherein the roasting temperature is 650 ° C to 800 ° C.
<3> The method for recovering a valuable material from a lithium ion secondary battery according to any one of <1> to <2>, wherein the particle size of the recovered material obtained in the sieve selection step is 1 mm or less. .
<4> The pulverization step is a step of pulverizing the roasted product by striking with a rotating impactor and passing the screen having a mesh size of 5 mm to 20 mm after the striking to obtain a pulverized product from <1> to <3> The method for recovering valuable materials from the lithium ion secondary battery according to any one of 3).
<5> The method for recovering a valuable material from a lithium ion secondary battery according to any one of <1> to <4>, wherein the valuable material is at least one of cobalt and nickel.
<6> A recovered material containing a valuable material obtained by the method for recovering a valuable material from a lithium ion secondary battery according to any one of <1> to <5>.

  According to the present invention, the conventional problems can be solved, valuable materials such as cobalt and nickel can be recovered from the lithium ion secondary battery at a high recovery rate, and a valuable material recovery method with a simple process, and A recovered material containing a valuable resource obtained by the recovery method can be provided.

FIG. 1 is a graph showing the cumulative mass ratio of the collected material on each sieve and under the sieve at each roasting temperature. FIG. 2 is a graph showing the relationship between the roasting temperature and the recovery rates of cobalt and nickel in Comparative Example 1 and Examples 1-8. FIG. 3 is a graph showing the impurity content in the recovered materials of Examples 5 to 8 and Comparative Example 2. FIG. 4 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 1. FIG. 5 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 2. FIG. 6 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 3. FIG. 7 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 4. FIG. 8 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 5. FIG. 9 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 6. FIG. 10 is a graph showing the content ratios of various metals in the collected material under each sieve and under the sieve in Example 7. FIG. 11 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 8. FIG. 12 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 9. FIG. 13 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Example 10. FIG. 14 is a graph showing the content ratios of various metals in the collected material on each sieve and under the sieve in Comparative Example 1. FIG. 15 is a graph showing the content ratios of various metals in the collected material under each sieve and under the sieve in Comparative Example 2. FIG. 16 is a photograph of a pulverized product obtained by pulverization by impact. FIG. 17 is a photograph of a crushed material obtained by shearing.

(Recovery method of valuable materials from lithium ion secondary batteries and recovered materials containing valuable materials)
The method for recovering valuable materials from the lithium ion secondary battery of the present invention includes at least a roasting step, a pulverization step, and a sieve selection step in this order, and further includes other steps as necessary.
The recovered material containing the valuable material of the present invention is obtained by the method for recovering the valuable material from the lithium ion secondary battery of the present invention.

<Roasting process>
The roasting step is not particularly limited as long as it is a step of obtaining a roasted product by roasting a lithium ion secondary battery at a roasting temperature of 400 ° C. or higher, and can be appropriately selected according to the purpose.

-Lithium ion secondary battery-
The lithium ion secondary battery is not particularly limited and may be appropriately selected depending on the purpose. For example, a defective lithium ion secondary battery generated in the process of manufacturing a lithium ion secondary battery, used equipment Examples thereof include a lithium ion secondary battery that is discarded due to a defect, a life of a device used, a used lithium ion secondary battery that is discarded due to a life.

There is no restriction | limiting in particular as a material of the said lithium ion secondary battery, a shape, a structure, and a magnitude | size, According to the objective, it can select suitably.
Examples of the lithium ion secondary battery include a positive electrode, a negative electrode, a separator, an electrolyte solution containing an electrolyte and an organic solvent, and a battery case that houses the positive electrode, the negative electrode, the separator, and the electrolyte solution. The ones provided are listed.

There is no restriction | limiting in particular as said positive electrode, According to the objective, it can select suitably, For example, the positive electrode provided with the electrical power collector which consists of aluminum foil, and the positive electrode material provided on the said electrical power collector is mentioned. It is done.
The positive electrode material is not particularly limited as long as it contains valuable materials, and can be appropriately selected according to the purpose.For example, the positive electrode material includes at least a composite oxide containing valuable materials, and if necessary, a conductive agent and And a positive electrode material containing a binder resin.
Examples of the valuable materials include cobalt and nickel.
Examples of the composite oxide include lithium cobaltate (LiCoO ₂ ), lithium cobalt nickelate (LiCo _1/2 Ni _1/2 O ₂ ), and LiNi _x Co _y Mn _z O _{2 (x + y + z)} .

-Roasting-
The roasting is not particularly limited as long as the roasting temperature is 400 ° C. or higher, and can be appropriately selected according to the purpose.
By performing the roasting at a roasting temperature of 400 ° C. or higher, the current collector (for example, aluminum foil) to which the positive electrode material containing a valuable material is adhered is easily melted and separated from the positive electrode material. Become. Therefore, the positive electrode material is finely pulverized by the pulverization in the pulverization step, and the positive electrode material containing valuable materials and iron such as the current collector and the battery case can be highly selected by a sieve.
On the other hand, when the roasting temperature is less than 400 ° C., the current collector is hardly melted, and as a result, the recovery rate of the valuables is lowered.
Here, the roasting temperature refers to the temperature of the lithium ion secondary battery during roasting. The roasting temperature can be measured by inserting a thermometer such as a couple or thermistor into the lithium ion secondary battery being roasted.

  The roasting temperature of the roasting is not particularly limited as long as it is 400 ° C or higher, and can be appropriately selected according to the purpose, but is preferably 650 ° C to 800 ° C, and more preferably 700 ° C to 800 ° C. When the roasting temperature is less than 400 ° C., the recovery rate of valuable materials such as cobalt and nickel is lowered. When the roasting temperature exceeds 800 ° C., it may be impossible to recover a desired valuable material by melting the battery case constituent material.

  There is no restriction | limiting in particular as roasting time, Although it can select suitably according to the objective, 1 minute-5 hours are preferable, within 2 hours are more preferable, and within 1 hour are especially preferable. The roasting time may be a roasting time for the current collector and the positive electrode material to reach a desired temperature, and the holding time may be short. When the roasting time is within the particularly preferable range, it is advantageous in terms of cost for roasting.

  There is no restriction | limiting in particular as said roasting method, According to the objective, it can select suitably, For example, performing using a roasting furnace is mentioned. Examples of the roasting furnace include a rotary kiln, a fluidized bed furnace, a tunnel furnace, a batch furnace such as a muffle, a cupola, and a stalker furnace.

There is no restriction | limiting in particular as atmosphere used for the said baking, According to the objective, it can select suitably, For example, air atmosphere, oxidizing atmosphere, inert atmosphere, reducing atmosphere etc. are mentioned. The atmosphere is preferably aerated during roasting.
Here, the air atmosphere (air atmosphere) means an atmosphere using air (air) in which oxygen is 21% by volume and nitrogen is 78% by volume.
The oxidizing atmosphere means an atmosphere containing 1% by mass to 21% by mass of oxygen in an inert atmosphere such as nitrogen or argon, and an atmosphere containing 1% by mass to 5% by mass of oxygen is preferable.
The inert atmosphere means an atmosphere made of nitrogen or argon.
The reducing atmosphere means an atmosphere containing CO, H ₂ , H ₂ S, SO ₂ and the like in an inert atmosphere such as nitrogen or argon.
Among these, an air atmosphere (air atmosphere) is preferable in terms of easy control of the furnace atmosphere.

<Crushing process>
The pulverization step is not particularly limited as long as it is a step of pulverizing the roasted product by hitting to obtain a pulverized product, and can be appropriately selected according to the purpose.

-Grinding-
The pulverization is not particularly limited as long as it is pulverization by impact, and can be appropriately selected according to the purpose.
Examples of the method of performing the impact include a method of hitting the roasted material with a rotating impactor (beater), and for example, it can be performed with a hammer crusher or the like. Further, there is a method of hitting the roasted material with a ball of ceramic or the like, which can be performed by a ball mill or the like. Moreover, it can carry out by grind | pulverizing with the biaxial crusher with a short blade width and the blade span which grind | pulverizes by compression.
The positive electrode material containing the valuable material separated from the current collector by the roasting is finely pulverized by performing the pulverization by the blow, while iron such as the current collector and the battery case is pulverized too much. As a result, the valuables and the iron are divided into particle sizes that can be highly sorted by a sieve.

  On the other hand, when crushing by shearing using a biaxial shearing crusher having a blade width of 10 mm and a long blade span as described in JP-A-7-207349 and JP-A-7-245126, the positive electrode material is It is hard to be crushed finely. In addition, the cutting surface of the battery casing extends, and a part of the positive electrode material containing the valuable material remains on the sieve. As a result, the recovery rate of the valuable material in the recovered material obtained under the sieve is lowered.

In addition, there exists a clear difference as shown in FIG. 16 and FIG.
In pulverization by striking, the powdery positive electrode material is removed from the battery case (housing) of the lithium ion secondary battery by striking, and the housing becomes a size that is easy to sort in a large state of several mm. As a result, the recovery rate of valuable materials by sieving increases.
On the other hand, in the crushing by shearing, the casing cutting surface extends to take in the positive electrode material existing inside the casing. From this, the recovery rate of the valuables in the positive electrode material when sieving is lowered.

  The peripheral speed of the rotating body that gives the impact is not particularly limited and can be appropriately selected according to the purpose, but is preferably 6 m / second to 100 m / second, more preferably 20 m / second to 70 m / second, 30 m / second to 50 m / second is particularly preferable. If the peripheral speed is less than 6 m / sec, the positive electrode material may not be finely pulverized, and if it exceeds 100 m / sec, it may be excessively pulverized. It is advantageous that the positive electrode material can be finely pulverized when the peripheral speed is within the particularly preferable range.

  The pulverization time is not particularly limited and may be appropriately selected depending on the purpose. The treatment time per kg of the lithium ion secondary battery is preferably 1 second to 30 minutes, more preferably 2 seconds to 10 minutes, 3 seconds to 5 minutes is particularly preferable. If the pulverization time is less than 1 second, it may not be pulverized, and if it exceeds 30 minutes, it may be excessively pulverized.

In the hitting, in the case of a method of hitting the roasted material with a rotating hitter (beater) (for example, a method using a hammer crusher), it is preferable to pass a screen and obtain a pulverized product after the hitting. .
There is no restriction | limiting in particular as an opening of the said screen, Although it can select suitably according to the objective, 5 mm or more is preferable, 5 mm-20 mm are more preferable, 10 mm-20 mm are especially preferable. If the opening of the screen is less than 5 mm, it may be excessively pulverized and iron may be mixed into the recovered material on the sieve. If it exceeds 20 mm, the battery will not be pulverized and the recovery rate of the positive electrode material will decrease. There are things to do.

The pulverization may be dry pulverization or wet pulverization.
The wet pulverization can be performed using water, an organic solvent, or the like.
Examples of the water include acidic water, neutral water, and alkaline water.
Examples of the organic solvent include alcohol solvents, glycol solvents, glycol ether solvents, and the like. Examples of the alcohol solvent include methanol, ethanol, propanol, isopropanol, butanol, 2-butanol, tert-butanol, and the like. Examples of the glycol solvent include ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol. Examples of the glycol ether solvent include ethylene glycol methyl ether, propylene glycol methyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol propyl ether, diethylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, and dipropylene glycol. Propyl ether, Dipropylene glycol butyl ether, Triethylene glycol methyl ether, Triethylene glycol ethyl ether, Triethylene glycol propyl ether, Triethylene glycol butyl ether, Tripropylene glycol methyl ether, Tripropylene glycol ethyl ether, Tripropylene group Call propyl ether, tripropylene glycol butyl ether.

-Crushed product-
There is no restriction | limiting in particular as a magnitude | size of the said ground material, Although it can select suitably according to the objective, 0.0075 mm-50 mm are preferable, 0.025 mm-20 mm are more preferable, 0.075 mm-5 mm are especially preferable. preferable. If the size is less than 0.0075 mm, dust may be generated, and it may be necessary to take measures against dust. If the size exceeds 50 mm, the battery is not sufficiently crushed, and impurities and the positive electrode material are sieved. In some cases, the recovery rate of the valuables may be reduced. When the size is within the particularly preferable range, it is advantageous in that the positive electrode material can be easily separated by sieving.
Here, the size of the pulverized product is determined by sieving with a test sieve.

  When the wet pulverization is performed in the pulverization, the pulverized product may be dried to remove volatile components.

<Screening process>
The sieving selection step is not particularly limited as long as it is a step of sieving the pulverized product and selecting it on a sieve and under a sieve to obtain a recovered material containing valuables under the sieve, depending on the purpose. It can be selected appropriately.

-Sieving-
There is no restriction | limiting in particular as said sieving, According to the objective, it can select suitably, For example, it can carry out using a vibration sieve, a multistage vibration sieve, a cyclone, the standard sieve of JISZ8801, etc.
There is no restriction | limiting in particular as opening of the mesh of a sieve, Although it can select suitably according to the objective, 0.025 mm-2 mm are preferable, 0.025 mm-1.5 mm are more preferable, 0.075 mm- 1 mm is particularly preferable. When the mesh opening is less than 0.025 mm, the recovery rate of the valuables under the sieve may be reduced. When the mesh size exceeds 2 mm, iron scraps and the like are mixed under the sieve and further sorted. A process may be required. When the mesh opening is within the particularly preferable range, it is advantageous in that the recovery rate of the valuable material is improved.

  The sieving may be dry or wet.

On the sieve selected by the sieving, iron, aluminum and the like are mainly contained as iron scraps and aluminum foil, and the positive electrode material is mainly contained under the sieve.
The sieving is usually performed while shaking the sieve, in other words, applying vibration to the sieve. For example, even if cobalt is wrapped in iron scrap or aluminum foil in the pulverized product, it is wrapped by vibration. Since the cobalt can be separated from iron scraps and aluminum foil, the positive electrode material finely pulverized by the pulverization step is sorted under a sieve with high efficiency.

In the sieving selection step, the sieving may be further sieved.
Here, in the sieving selection step, when further sieving the sieving, the sieving on the first sieving is referred to as the first sieving, and the sieving is referred to as the first sieving, The top of the sieve when the first sieve is further sieved is called the second sieve, and the sieve is called the second sieve.
By further sieving the first sieving material, the carbon that is the material of the negative electrode is moved under the second sieving material, and the recovered material containing the valuable material remaining on the second sieving material is used. The carbon can be separated.
In the case of further sieving the first sieve, a multistage sieve can be used in the sieve sorting step. In addition, the first sieve and the second sieve can be sieved again.
There is no restriction | limiting in particular as an opening of the sieve screen at the time of further sieving the said 1st sieve bottom, Although it can select suitably according to the objective, 0.0075 mm-0.3 mm are preferable. 0.025 mm to 0.15 mm is more preferable, and 0.025 mm to 0.075 mm is particularly preferable. If the mesh opening is less than 0.0075 mm, the particle size may be too small to make separation difficult, and if it exceeds 0.3 mm, the recovery rate of the valuables may be reduced. . When the mesh opening is within the particularly preferred range, it is advantageous in that the amount of the valuable material lost when the sieve is removed can be reduced as much as possible.

  The particle size of the recovered material under the sieving (first sieving) obtained in the sieving selection step is not particularly limited and can be appropriately selected according to the purpose. This is preferable from the viewpoint of increasing the separation efficiency between the battery case material and the valuables. Examples of the method for setting the particle size to 1 mm include sieving with a sieve having an opening of 1 mm.

In the method of recovering valuable materials from the lithium ion secondary battery, it is not necessary to perform a secondary roasting step or a magnetic force selection step after the sieve selection step, and the process is simple and has a high recovery rate. Valuables such as cobalt and nickel can be recovered.
On the other hand, in the inventions described in JP-A-7-207349 and JP-A-7-245126, a secondary roasting process and a magnetic screening process are necessary after the screening process, and many processes are required. In addition, the recovery rate of valuable materials such as cobalt and nickel is not as high as the present invention.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples.

Example 1
A used lithium ion secondary battery for a personal computer was used as the lithium ion secondary battery. Regarding the metal content of the lithium ion secondary battery used, lithium is 2.2% by mass, cobalt is 10.7% by mass, and manganese is 9.9% when the mass of the lithium ion secondary battery is 100% by mass. 93% by mass, nickel was 7.63% by mass, copper was 11.51% by mass, and iron was 18.24% by mass.
-Roasting process-
A lithium ion secondary battery was placed in a muffle furnace (FJ-41, manufactured by Yamato Scientific Co., Ltd.), the roasting temperature was 400 ° C., and the temperature was increased to 400 ° C. at a temperature increase rate of 10 ° C./min. After reaching the temperature, it was baked for 1 hour to obtain a baked product. The atmosphere in the furnace was an air atmosphere.
-Crushing process-
The roasted material obtained by the roasting step was pulverized for 15 seconds at 50 Hz (about 2,500 rpm, peripheral speed 46 m / sec) using a hammer crusher (HC-20, manufactured by Hadano Sangyo Co., Ltd.) to obtain a pulverized product. It was. The screen at this time used an opening of 20 mm. Further, the hammer crusher used this time has a striker size of 50 mm in width, 124 mm in length, and 25 mm in height, and is connected to 20 shafts of the main body.
-Screening process-
The pulverized product obtained by the pulverization step was sieved using sieves having mesh openings of 2.00 mm, 1.00 mm, and 0.60 mm in three stages.

<Evaluation>
After sieving, 2.00 mm sieve top (A), 1.00 mm sieve top (B), 0.6 mm sieve top (C), under sieve (D) (0.6 mm Each sample is taken and measured for mass, dissolved in aqua regia by heating, and analyzed by a high frequency inductively coupled plasma emission spectrometer (iCaP6300, manufactured by Thermo Fisher Scientific Co.) to obtain cobalt and nickel. The recovery rate and the content ratios of various metals recovered were determined. The results are shown in Tables 1-2 and FIGS.

(Examples 2 to 10, Comparative Example 1)
In Example 1, except that the roasting temperature shown in Table 1 and the screen size of the hammer crusher were changed, the roasting step, the pulverizing step, and the sieve sorting step were performed in the same manner as in Example 1, and the sorting was performed. The mass was measured later, and the recovery rate of cobalt and nickel and the content ratios of various metals recovered were determined. A result is shown to Tables 1-2 and FIGS. 1-3, 5-14.

(Comparative Example 2)
In Example 7, instead of the hammer crusher (HC-20, manufactured by Hadano Sangyo Co., Ltd.), a good cutter (UG-102-10-240, manufactured by Ujiie Seisakusho, blade width 10 mm) which is a shear type crusher was used. Except for crushing for 2 seconds, the roasting step, crushing step, and sieve sorting step were performed in the same manner as in Example 7, the mass was measured after sorting, and the recovery rate of cobalt and nickel were further recovered. The content ratio of various metals was determined. The results are shown in Tables 1-2 and FIG.

  Table 1 shows the mass, mass ratio, and integrated mass ratio of the collected material on each sieve after sieve selection and under the sieve. Moreover, the graph of the integrated mass ratio of the collection thing on each sieving in each roasting temperature in FIG. 1 is shown.

As shown in Table 1 and FIG. 1, when the roasting temperature is less than 400 ° C. (Comparative Example 1) compared to the case where the roasting temperature is 400 ° C. or higher (Examples 1 to 10), the sieve (D) It can be seen that the mass of the recovered material is small and is not finely pulverized.

  In Table 2 and FIG. 2, the recovered material that passed through a sieve having a sieve mesh opening of 1.0 mm at each roasting temperature (recovered material on the sieve of 0.6 mm sieve (C) and under sieve (D) The recovery rate of cobalt and the recovery rate of nickel. This recovery rate is a recovery rate when the mass of cobalt and nickel contained in the lithium ion secondary battery used in the experiment is 100%.

As shown in Table 2 and FIG. 2, when the roasting temperature is 400 ° C. or higher (Examples 1 to 10), the roasting temperature is less than 400 ° C. (Comparative Example 1), compared with cobalt and nickel. The recovery was very good.
Moreover, as shown in Table 2 and FIG. 2, even when the roasting temperature is sufficiently high (750 ° C. to 800 ° C.), when a hammering crusher (hammer crusher) is used (Examples 7 to 10) Compared with the case of using a shearing crusher (Comparative Example 2), the recovery rate of cobalt and nickel was very excellent.

  FIG. 3 shows the impurity contents in the recovered materials of Examples 5 to 8 and Comparative Example 2. Comparing these, it can be seen that at a roasting temperature of 650 ° C. to 800 ° C., which is a preferred example of the present invention, recovery is performed with more impurities separated than in Comparative Example 2.

In FIGS. 4-15, the graph of the content rate of various metals with respect to the collection thing of each sieve top of Examples 1-10 and Comparative Examples 1 and 2 and a sieve was shown. In addition, the remainder of a graph shows metals and organic substances (mainly carbon) and oxygen other than detection. In addition, the mass ratio (A + B + C + D is 100% of the total mass in Table 1) of each sieve and the sieve below the total amount obtained by adding the sieve and the sieve below the horizontal axis of the graph. Shown in the column.
In Examples 1 to 10 where the roasting temperature is 400 ° C. or higher, the content ratio of iron, copper and aluminum is high on the sieve (A) of the 2.00 mm sieve having a high mass ratio, and cobalt is a valuable material. , The nickel content was very low (almost not contained). On the other hand, in the sieving (D) with a high mass ratio (under sieving of 0.6 mm sieve), the contents of valuable cobalt and nickel were high, and the contents of iron, copper, and aluminum were very low. . That is, valuable metals such as cobalt and nickel were highly separated from other metals such as iron, copper and aluminum.
On the other hand, in the comparative example 1 whose roasting temperature is 300 ° C., on the sieve top (A) of the 2.00 mm sieve having a high mass ratio, the same degree as the sieve below (D) (0.6 mm sieve sieve). Cobalt and nickel, which are valuable materials, were included in the content ratio of. That is, separation of valuable metals such as cobalt and nickel from other metals such as iron, copper, and aluminum was insufficient.

  In Examples 9 and 10, the screen size of the hammer crusher was 5 mm and 10 mm. When the screen size was 5 mm (Example 9) and 10 mm (Example 10), the screen size was 0.6 mm. The amount of iron increased as compared with a screen opening of 20 mm (Example 8). In addition, Examples 8-10 are the same conditions except a screen opening. For this reason, the iron content of the recovered material can be reduced when the screen opening is 10 mm or more.

  The method for recovering valuable materials according to the present invention can recover valuable materials such as cobalt and nickel from a lithium ion secondary battery at a high recovery rate and has a simple process. It can be suitably used for recovery.

Claims (6)

A roasting step of roasting a lithium ion secondary battery at a roasting temperature of 400 ° C. or higher to obtain a roasted product;
A pulverizing step of pulverizing the roasted product by hitting to obtain a pulverized product;
Sieving the pulverized material into a sieve and a sieve, and a sieve sorting step for obtaining a recovered material containing the valuable material under the sieve. Collection method.   The method for recovering valuable materials from a lithium ion secondary battery according to claim 1, wherein the roasting temperature is 650C to 800C.   The method for recovering a valuable material from a lithium ion secondary battery according to any one of claims 1 to 2, wherein the particle size of the recovered material obtained under the sieving step is 1 mm or less.   The pulverization step is a step of pulverizing the roasted product by striking with a rotating striker and passing the screen through a screen having a mesh opening of 5 mm to 20 mm to obtain a pulverized product. A method for recovering valuable materials from the lithium ion secondary battery described.   The method for recovering a valuable material from a lithium ion secondary battery according to any one of claims 1 to 4, wherein the valuable material is at least one of cobalt and nickel.   A recovered material containing a valuable material obtained by the method for recovering a valuable material from a lithium ion secondary battery according to any one of claims 1 to 5.