CN114361637A - Method for separating electrode material and foil of lithium battery - Google Patents

Abstract

The invention provides a method for separating an electrode material and a foil of a lithium battery, which comprises the following steps: and mixing the positive pole piece and/or the negative pole piece with the ball-milled beads, vibrating and roasting in sections, and separating to obtain a positive pole material and/or a negative pole material, and an aluminum foil and/or a copper foil. The invention adopts a simple method to effectively separate the anode/cathode material and the foil, can obtain electrode materials with different grades, has controllable aluminum and/or copper impurity content, and has the advantages of safe and environment-friendly whole recovery process, simple process, low energy consumption, good economy and the like.

Description

A kind of separation method of lithium battery electrode material and foil material

technical field

The invention relates to the field of processing and recycling of waste materials of lithium ion batteries, in particular to a method for separating electrode materials and foils of lithium batteries.

Background technique

Thanks to the advantages of high voltage, high energy density, and good cyclability, lithium-ion batteries have been widely used in mobile smart terminals, small electric equipment, grid energy storage, and electric vehicles. According to statistics, in 2019 alone, my country produced as many as 15.72 billion lithium-ion batteries. As the use of lithium-ion batteries increases, so does their retirement. It is estimated that between 2017 and 2030, more than 11 million tons of decommissioned lithium-ion batteries are expected to be produced globally.

Li, Ni, Co, Mn, Fe, Cu, Al and other metals are used in lithium-ion batteries, and decommissioned lithium-ion batteries are rich and valuable technical deposits. The recycling of lithium-ion batteries has important economic and environmental significance.

After the waste lithium-ion battery is subjected to pretreatment such as discharge and disassembly, a positive/negative electrode material containing foil is obtained. For the separation of positive/negative electrode materials and foils, there are mainly alkaline solution dissolution method, organic solvent dissolution method, and high temperature pyrolysis. The alkaline solution dissolution method has serious exothermic heat, the reaction is not easy to control, and hydrogen is generated, and at the same time, the equipment is seriously corroded, and the processing cost is high. The organic solvent dissolution method has serious solvent volatilization, poor recycling and toxic. Pyrolysis at high temperature has high energy consumption and produces a large amount of harmful waste gas containing fluorine, which is easy to cause secondary pollution.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned problems of separating positive/negative electrode materials and foils in the prior art, the present invention provides a method for separating lithium battery electrode materials and foils.

In order to achieve the above purpose, an embodiment of the present invention provides a method for separating a lithium battery electrode material and a foil material. The separating method includes the following steps:

S1: Mix the primary positive pole piece and/or negative pole piece obtained after the dismantling of the retired lithium battery with ball mill beads, and bake and vibrate to obtain the primary recovered positive pole material and/or negative pole material, the secondary positive pole piece and/or respectively. or negative pole piece;

S2: mixing the secondary positive pole piece and/or the negative pole piece with the ball mill beads, roasting and vibrating to obtain the secondary recycled positive pole material and/or negative pole material, and the tertiary positive pole piece and/or the negative pole piece respectively;

S3: Mixing the tertiary positive pole piece and/or the negative pole piece with the ball mill beads, roasting and vibrating, to obtain the tertiary recovered positive pole material and/or negative pole material, and the quaternary positive pole piece and/or the negative pole piece respectively;

S4: Mix the quaternary positive pole piece and/or the negative pole piece with the ball mill beads, bake and vibrate, and obtain the quaternary recycled positive electrode material and/or negative electrode material, waste aluminum foil and/or copper foil, respectively.

Further, in the step S1, the mass ratio of the first-stage positive pole piece and/or the negative pole piece mixed with the ball mill beads is 1:1-10.

Further, in the step S1, the roasting temperature is 100-150° C., the roasting time is 2-30 min, and the vibration frequency of the ball milling bead is 20-300 times/min.

Further, in the step S2, the mass ratio of the secondary positive pole piece and/or the negative pole piece mixed with the ball mill beads is 1:5-12.

Further, in the step S2, the calcination temperature is 150-200° C., the vibration frequency of the ball milling bead is 60-300 times/min, and the calcination time is 5-60 min.

Further, in the step S3, the mass ratio of the tertiary positive pole piece and/or the negative pole piece mixed with the ball mill beads is 1:10-20.

Further, in the step S3, the roasting temperature is 200-250° C., the vibration frequency of the ball milling bead is 20-200 times/min, and the roasting time is 2-40 min.

Further, in the step S4, the mass ratio of the four-stage positive pole piece and/or the negative pole piece mixed with the ball mill beads is 1:5-25.

Further, in the step S4, the roasting temperature is 250-350° C., the vibration frequency of the ball milling bead is 30-200 times/min, and the roasting time is 1-20 min.

Further, the material of the ball grinding beads in the step S1 is one or more of zirconia, aluminum oxide, polyurethane, and stainless steel, and the material of the ball grinding beads in the step S2 is one or more of zirconia, aluminum oxide, and stainless steel. In the step S3, the material of the ball grinding beads is one or both of zirconia and aluminum oxide, and the material of the ball grinding beads in the step S4 is zirconia.

In the present invention, the positive pole piece and/or the negative pole piece obtained after the dismantling of the decommissioned lithium battery is mixed with the ball mill beads, and then calcined in sections while vibrating, so that the ball mill ball bounces and fully contacts the positive pole piece and/or the negative pole piece, The positive electrode material and/or the negative electrode material are separated from the aluminum foil and/or the copper foil by the mechanical force generated when the two are in contact.

The above-mentioned scheme of the present invention has the following beneficial effects:

1) the described separation method of the above-mentioned scheme of the present invention is to mix the positive pole piece and/or the negative pole piece with ball mill beads, vibrate again, the method for subsection roasting, obtain different grades of reclaimed material in sections: one level, two levels The aluminum content in the recycled positive electrode material is 0; the copper content in the primary and secondary recycled negative electrode materials is 0; the aluminum content in the tertiary recycled positive electrode material is 10 ppm, the copper content in the tertiary recycled negative electrode material is 10 ppm, and the fourth recycled positive electrode material is contained. The content of aluminum in the middle is 100ppm, and the content of copper in the fourth-stage recovery negative electrode material is 30ppm;

2) the present invention mixes the positive pole piece and/or the negative pole piece with the ball mill beads, vibrates again, and the method for subsection roasting reduces the processing cost, and simultaneously avoids the use of the existing lye, organic solvent, high temperature pyrolysis technology. damage to the environment and humans.

Description of drawings

FIG. 1 is a process flow diagram of a method for separating positive/negative electrode materials and foil materials of a lithium battery according to an embodiment of the present invention.

Detailed ways

In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, the following will be described in detail with reference to the accompanying drawings and specific embodiments.

Unless otherwise defined, all technical terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments, and are not intended to limit the protection scope of the present invention. Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention are all It can be purchased from the market or can be prepared by existing methods.

In view of the existing problems, the present invention provides a method for separating lithium battery electrode material and foil material.

As shown in FIG. 1 , an embodiment of the present invention provides a process flow diagram of a method for separating a lithium battery electrode material and a foil material.

Example 1

Take used lithium-ion batteries, clean their casings, and dry them completely at 20°C. The dried waste lithium-ion battery is disassembled in a protective atmosphere to obtain an outer casing and a battery core pack, and the battery core pack is arbitrarily cut into pieces to obtain a mixed sheet containing positive/negative electrode materials and foil.

The first-stage negative pole piece and zirconia ball grinding beads are mixed according to the mass ratio of 1:10, and then calcined at a temperature of 150 ℃ in the first interval for 30 min, and vibrated at a frequency of 300 times/min to separate the negative electrode material from the copper foil to obtain Primary recovery of negative electrode materials and secondary negative electrode plates;

The secondary negative pole piece and zirconia ball grinding beads are mixed according to the mass ratio of 1:12, and then roasted at a temperature of 200 ° C in the second interval for 60 min, and vibrated at a frequency of 200 times/min to separate the negative electrode material from the copper foil to obtain Secondary recovery of negative electrode materials and tertiary negative pole pieces;

The tertiary negative pole piece and the zirconia ball grinding beads are mixed according to the mass ratio of 1:20, and then roasted at a temperature of 250 ℃ in the third interval for 40 minutes, and vibrated at a frequency of 200 times/min at the same time, and the negative electrode material was separated from the copper foil to obtain three. Recycled negative electrode material and four-stage negative pole piece;

The fourth-stage negative pole piece and zirconia ball grinding beads were mixed according to the mass ratio of 1:25, and then roasted at a temperature of 350 ° C in the fourth interval for 20 min, and vibrated at a frequency of 200 times/min at the same time, and the negative electrode material was separated from the copper foil to obtain four. Advanced recycling of anode materials and scrap copper foil.

Table 1 Example 1 of the present invention obtains the copper content in the recovered negative electrode material

Example 2

Take used lithium-ion batteries, clean their casings, and dry them completely at 20°C. The dried waste lithium-ion battery is disassembled in a protective atmosphere to obtain an outer casing and a battery core pack, and the battery core pack is arbitrarily cut into pieces to obtain a mixed sheet containing positive/negative electrode materials and foil.

Mix the first-stage positive/negative electrode mixed pole piece with zirconia or stainless steel ball mill beads in a mass ratio of 1:5, and then bake for 15 minutes at a temperature of 125 °C in the first interval, while vibrating at a frequency of 150 times/min to make the positive electrode material and the The negative electrode material is separated from the aluminum foil and the copper foil, respectively, to obtain a first-level positive/negative electrode mixed material and a second-level positive/negative electrode mixed pole piece;

The secondary positive/negative electrode mixed pole piece is mixed with zirconia and stainless steel ball mill beads in a mass ratio of 1:10, and then calcined at a temperature of 175°C for 30 minutes in the second interval, while vibrating at a frequency of 150 times/min, so that the positive electrode material and the The negative electrode material is separated from the aluminum foil and the copper foil, respectively, to obtain a secondary positive/negative electrode mixed material and a tertiary positive/negative electrode mixed pole piece;

The three-stage positive/negative electrode mixed pole piece is mixed with zirconia and alumina ball grinding beads according to the mass ratio of 1:15, and then calcined at the third interval temperature of 225 ° C for 20 minutes, while vibrating at a frequency of 100 times/min to make the positive electrode The material and the negative electrode material are separated from the aluminum foil and the copper foil, respectively, to obtain a tertiary positive/negative electrode mixed material and a quaternary positive/negative electrode mixed pole piece;

The four-stage positive/negative mixed pole piece is mixed with zirconia and alumina ball grinding beads in a mass ratio of 1:20, and then roasted at a temperature of 275 ° C in the fourth interval for 10 minutes, while vibrating at a frequency of 100 times/min to make the positive electrode material. and the negative electrode material are separated from aluminum foil and copper foil, respectively, to obtain four-level positive/negative electrode mixed material and waste positive/negative electrode mixed polar piece;

Example 3

Take used lithium-ion batteries, clean their casings, and dry them completely at 20°C. The dried waste lithium-ion battery is disassembled in a protective atmosphere to obtain an outer casing and a battery core pack, and the battery core pack is arbitrarily cut into pieces to obtain a mixed sheet containing positive/negative electrode materials and foil.

The first-stage positive electrode piece is mixed with zirconia and polyurethane ball grinding beads in a mass ratio of 1:1, and then baked at a temperature of 100 °C in the first interval for 7.5 minutes, while vibrating at a frequency of 75 times/min to separate the positive electrode material from the aluminum foil. , to obtain primary recycled positive electrode material and secondary positive electrode sheet;

The secondary positive pole piece and the alumina ball grinding beads were mixed according to the mass ratio of 1:5, and then roasted at a temperature of 150 ° C in the second interval for 15 min, while vibrating at a frequency of 75 times/min to separate the positive electrode material from the aluminum foil to obtain two. Grade recycling cathode material and tertiary cathode plate;

The tertiary positive pole piece is mixed with zirconia or alumina ball grinding beads according to the mass ratio of 1:10, and then roasted at a temperature of 200 ℃ in the third interval for 10 minutes, while vibrating at a frequency of 50 times/min to separate the positive electrode material from the aluminum foil , to obtain tertiary recycled cathode materials and quaternary cathode plates;

The fourth-stage positive pole piece and the zirconia ball grinding beads were mixed according to the mass ratio of 1:15, and then roasted at a temperature of 250 ° C in the fourth interval for 5 min, and at the same time, the positive electrode material was separated from the aluminum foil by vibrating at a frequency of 50 times/min. Grade recycling cathode material and waste aluminum foil;

Table 3 Example 3 of the present invention obtains the aluminum content in the recovered positive electrode material

Table 4 Example 3 of the present invention obtains the recovery rate of the recovered positive electrode material

Comparative Example 1

Take used lithium-ion batteries, clean their casings, and dry them completely at 20°C. The dried waste lithium-ion battery is disassembled in a protective atmosphere to obtain an outer casing and a battery core pack, and the battery core pack is arbitrarily cut into pieces to obtain a mixed sheet containing positive/negative electrode materials and foil.

The first-stage negative pole piece and zirconia ball grinding beads are mixed according to the mass ratio of 1:10, and then calcined at a temperature of 150 ℃ in the first interval for 30 min, and vibrated at a frequency of 300 times/min to separate the negative electrode material from the copper foil to obtain Primary recovery of negative electrode materials and secondary negative electrode plates;

The secondary negative pole piece and zirconia ball grinding beads are mixed according to the mass ratio of 1:12, and then roasted at a temperature of 150 ° C in the first interval for 60 min, and vibrated at a frequency of 200 times/min to separate the negative electrode material from the copper foil to obtain Secondary recovery of negative electrode materials and tertiary negative pole pieces;

The tertiary negative pole piece and zirconia ball grinding beads were mixed according to the mass ratio of 1:20, and then roasted at a temperature of 150 ° C in the first interval for 40 min, and vibrated at a frequency of 200 times/min at the same time, and the negative electrode material was separated from the copper foil to obtain three. Recycled negative electrode material and four-stage negative pole piece;

The fourth-stage negative pole piece and zirconia ball grinding beads are mixed according to the mass ratio of 1:25, and then roasted at a temperature of 150 ° C in the first interval for 20 min, and vibrated at a frequency of 200 times/min at the same time, and the negative electrode material is separated from the copper foil to obtain four. Advanced recycling of anode materials and scrap copper foil.

Table 5 Comparative Example 1 of the present invention obtains the copper content in the recovered negative electrode material

Table 6 Comparative Example 1 of the present invention obtains the recovery rate of the recovered negative electrode material

Comparative Example 2

Take used lithium-ion batteries, clean their casings, and dry them completely at 20°C. The dried waste lithium-ion battery is disassembled in a protective atmosphere to obtain an outer casing and a battery core pack, and the battery core pack is arbitrarily cut into pieces to obtain a mixed sheet containing positive/negative electrode materials and foil.

The first-stage negative pole piece and zirconia ball grinding beads are mixed according to the mass ratio of 1:10, and then calcined at a temperature of 150 ℃ in the first interval for 30 min, and vibrated at a frequency of 300 times/min to separate the negative electrode material from the copper foil to obtain Primary recovery of negative electrode materials and secondary negative electrode plates;

The secondary negative pole piece and zirconia ball grinding beads are mixed according to the mass ratio of 1:12, and then roasted at a temperature of 200 ° C in the second interval for 60 min, and vibrated at a frequency of 200 times/min to separate the negative electrode material from the copper foil to obtain Secondary recovery of negative electrode materials and tertiary negative pole pieces;

The tertiary negative pole piece and the zirconia ball grinding beads are mixed according to the mass ratio of 1:20, and then roasted at a temperature of 250 ℃ in the third interval for 40 minutes, and vibrated at a frequency of 200 times/min at the same time, and the negative electrode material was separated from the copper foil to obtain three. Recycled negative electrode material and four-stage negative pole piece;

The fourth-stage negative pole piece and zirconia ball grinding beads were mixed according to the mass ratio of 1:25, and then roasted at a temperature of 250 ° C in the third interval for 20 min, while vibrating at a frequency of 200 times/min, and the negative electrode material was separated from the copper foil to obtain four. Advanced recycling of anode materials and scrap copper foil.

Table 7 Comparative Example 2 of the present invention obtains the copper content in the recovered negative electrode material

Table 8 Comparative Example 2 of the present invention obtains the recovery rate of the recovered negative electrode material

Comparative Example 3

Take used lithium-ion batteries, clean their casings, and dry them completely at 20°C. The dried waste lithium-ion battery is disassembled in a protective atmosphere to obtain an outer casing and a battery core pack, and the battery core pack is arbitrarily cut into pieces to obtain a mixed sheet containing positive/negative electrode materials and foil.

The first-stage positive electrode piece is mixed with zirconia and polyurethane ball grinding beads in a mass ratio of 1:1, and then baked at a temperature of 100 °C in the first interval for 7.5 minutes, while vibrating at a frequency of 75 times/min to separate the positive electrode material from the aluminum foil. , to obtain primary recycled positive electrode material and secondary positive electrode sheet;

The secondary positive pole piece and the alumina ball grinding beads are mixed according to the mass ratio of 1:5, and then roasted at a temperature of 100 ° C in the first interval for 15 minutes, while vibrating at a frequency of 75 times/min to separate the positive electrode material from the aluminum foil to obtain two. Grade recycling cathode material and tertiary cathode plate;

The tertiary positive pole piece is mixed with zirconia or alumina ball grinding beads in a mass ratio of 1:10, and then roasted at a temperature of 100 ℃ in the first interval for 10 minutes, while vibrating at a frequency of 50 times/min to separate the positive electrode material from the aluminum foil , to obtain tertiary recycled cathode materials and quaternary cathode plates;

The fourth-stage positive pole piece and zirconia ball grinding beads were mixed according to the mass ratio of 1:15, and then roasted at a temperature of 100 ° C in the first interval for 5 minutes, and at the same time, the positive electrode material was separated from the aluminum foil by vibration at a frequency of 50 times/min. Grade recycling cathode material and waste aluminum foil;

Table 9 Comparative example 3 of the present invention obtains the aluminum content in the recovered positive electrode material

Table 10 Comparative Example 3 of the present invention obtains the recovery rate of the recovered positive electrode material

Comparative Example 4

This example is a comparative example. Take used lithium-ion batteries, clean their casings, and dry them completely at 20°C. The dried waste lithium-ion battery is disassembled in a protective atmosphere to obtain an outer casing and a battery core pack, and the battery core pack is arbitrarily cut into pieces to obtain a mixed sheet containing positive/negative electrode materials and foil.

The first-stage positive electrode piece is mixed with zirconia and polyurethane ball grinding beads in a mass ratio of 1:1, and then baked at a temperature of 100 °C in the first interval for 7.5 minutes, while vibrating at a frequency of 75 times/min to separate the positive electrode material from the aluminum foil. , to obtain primary recycled positive electrode material and secondary positive electrode sheet;

The secondary positive pole piece and the alumina ball grinding beads were mixed according to the mass ratio of 1:5, and then roasted at a temperature of 150 ° C in the second interval for 15 min, while vibrating at a frequency of 75 times/min to separate the positive electrode material from the aluminum foil to obtain two. Grade recycling cathode material and tertiary cathode plate;

The tertiary positive pole piece is mixed with zirconia or alumina ball grinding beads in a mass ratio of 1:10, and then baked at a temperature of 200 ℃ in the third interval for 10 minutes, and vibrates at a frequency of 50 times/min to separate the positive electrode material from the aluminum foil. , to obtain tertiary recycled cathode materials and quaternary cathode plates;

The fourth-stage positive pole piece and zirconia ball grinding beads were mixed according to the mass ratio of 1:15, and then roasted at a temperature of 200 ° C in the third interval for 5 minutes, and at the same time, the positive electrode material was separated from the aluminum foil by vibrating at a frequency of 50 times/min. Grade recycling cathode material and waste aluminum foil;

Table 11 Comparative Example 4 of the present invention obtains the aluminum content in the recovered positive electrode material

Table 12 Comparative Example 4 of the present invention obtains the recovery rate of the recovered positive electrode material

The above are the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. It should be regarded as the protection scope of the present invention.

Claims (10)

1. A method for separating an electrode material and a foil of a lithium battery is characterized by comprising the following steps:

s1: mixing a primary positive pole piece and/or a primary negative pole piece obtained after disassembly of a retired lithium battery with ball-milled beads, roasting and vibrating to respectively obtain a primary recovered positive pole material and/or a primary recovered negative pole material, and a secondary positive pole piece and/or a secondary negative pole piece;

s2: mixing the secondary positive pole piece and/or the secondary negative pole piece with the ball-milled beads, roasting and vibrating to respectively obtain a secondary recovered positive pole material and/or a secondary recovered negative pole material, and a tertiary positive pole piece and/or a tertiary negative pole piece;

s3: mixing the three-stage positive pole piece and/or negative pole piece with the ball-milled beads, roasting and vibrating to respectively obtain a three-stage recovered positive pole material and/or negative pole material, and a four-stage positive pole piece and/or negative pole piece;

s4: and mixing the four-stage positive pole piece and/or negative pole piece with the ball-milled beads, roasting and vibrating to respectively obtain four-stage recycled positive pole material and/or negative pole material, waste aluminum foil and/or copper foil.

2. The separation method according to claim 1, wherein the mass ratio of the primary positive electrode sheet and/or negative electrode sheet to the ball-milled beads in the step S1 is 1: 1 to 10.

3. The separation method as claimed in claim 1, wherein the calcination temperature in step S1 is 100-150 ℃, the calcination time is 2-30min, and the vibration frequency of the ball milling beads is 20-300 times/min.

4. The separation method according to claim 1, wherein the mass ratio of the secondary positive electrode sheet and/or negative electrode sheet mixed with the ball-milled beads in the step S2 is 1: 5 to 12.

5. The separation method as claimed in claim 1, wherein the calcination temperature in step S2 is 150 ℃ to 200 ℃, the vibration frequency of the ball milling beads is 60-300 times/min, and the calcination time is 5-60 min.

6. The separation method according to claim 1, wherein the mass ratio of the three-stage positive electrode sheet and/or negative electrode sheet to the ball-milled beads in the step S3 is 1: 10 to 20.

7. The separation method as claimed in claim 1, wherein the calcination temperature in step S3 is 200-250 ℃, the vibration frequency of the ball-milling beads is 20-200 times/min, and the calcination time is 2-40 min.

8. The separation method according to claim 1, wherein the mass ratio of the four-stage positive electrode sheet and/or negative electrode sheet to the ball-milled beads in the step S4 is 1: 5 to 25.

9. The separation method as claimed in claim 1, wherein the calcination temperature in step S4 is 250-350 ℃, the vibration frequency of the ball-milling beads is 30-200 times/min, and the calcination time is 1-20 min.

10. The separation method according to claim 1, wherein the ball milling beads in the step S1 are made of one or more of zirconia, alumina, polyurethane and stainless steel, the ball milling beads in the step S2 are made of one or more of zirconia, alumina and stainless steel, the ball milling beads in the step S3 are made of one or more of zirconia and alumina, and the ball milling beads in the step S4 are made of zirconia.

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