Heating equipment for realizing ultrafast recovery and regeneration of retired lithium ion battery key material

Abstract

The utility model discloses heating equipment for realizing ultrafast recovery and regeneration of a key material of a retired lithium ion battery, and belongs to the field of recovery and regeneration of lithium ion batteries. The heating equipment comprises a furnace body, a sample transmission device and a heating device; the heating device is positioned in the furnace chamber; the sample transmission device is arranged at the lower part of the furnace body; one side of the furnace body is a sample inlet, and the other side of the furnace body is a sample outlet; the furnace body is provided with an air inlet and an air outlet. The device can realize rapid structure repair of the retired positive electrode material, significantly reduce the time cost and energy loss in the material regeneration process, and also can realize large-scale preparation of kilogram-level or above.

Description

TECHNICAL FIELD

[0001] The application relates to a heating device for realizing superfast recycling and regeneration of key materials of retired lithium ion batteries, and belongs to the field of lithium ion battery recycling and regeneration. BACKGROUND

[0002] Compared with other traditional batteries, lithium ion batteries provide higher volumetric energy density (320-450 Wh / L), power output (more than 300 W / kg) and cycle stability (nearly 2000 cycles). Therefore, the field of electric vehicles using lithium ion batteries as energy storage units is booming. According to relevant forecasts, among different types of electric vehicles, pure electric vehicles account for a dominant position, accounting for about two-thirds of the registration quantity of new electric vehicles. The production of electric vehicles has increased significantly from 100,000 in 2010 to 11.26 million in 2020. It is predicted that the global production of electric vehicles will reach 21.5 million by 2030. The service life of lithium ion batteries is usually 5-10 years. Therefore, after the use stage, a large number of retired lithium ion batteries will enter the solid waste treatment stage. It is predicted that up to 4 million tons of retired lithium ion batteries based on electric vehicles will be generated in the next 20 years. A large number of retired lithium ion batteries bring many environmental and economic challenges. Therefore, efficient and sustainable recycling of key components of retired lithium ion batteries is imminent.

[0003] Compared with traditional pyrometallurgical and hydrometallurgical recycling of key materials of lithium ion batteries, direct regeneration is considered to be a more sustainable and more economical recycling mode. By repairing the structure of the positive electrode material of the retired lithium ion battery, the regenerated fresh positive electrode material is put into use. However, the existing direct recycling methods except the solid phase sintering method are difficult to realize large-scale production in the industry. The solid phase method strategy reported at present often needs a long time (6-10 hours) to heat the sample for a long time. The rapid Joule heating method can greatly shorten the regeneration time to seconds, but the existing Joule heating device can only realize the preparation of kilograms in the laboratory scale, and cannot realize the mass production in the industry. CONTENT OF THE UTILITY MODEL

[0004] In view of this, the application provides a heating device for realizing superfast recycling and regeneration of key materials of retired lithium ion batteries, and the main purpose is to solve the technical problems of complicated repair method of retired materials, long time and large batch production.

[0005] The application provides a heating device for realizing super-fast recycling and regeneration of key materials of retired lithium ion batteries. The heating device comprises a sample inlet, a super-fast sample transmission device, a furnace cavity, a heating device, an air inlet, an air outlet, an air path, and a sample outlet. The sample inlet is used for loading samples, and the samples are transmitted in the furnace cavity. The speed of the super-fast sample transmission device and the sintering temperature of the heating device can be adjusted. The air inlet, the air path, and the air outlet are connected to form a gas exchange unit, which is used for replacing the internal atmosphere of the furnace cavity. After the samples are sintered, they are taken out from the sample outlet.

[0006] The application provides a heating device for realizing super-fast recycling and regeneration of key materials of retired lithium ion batteries. The heating device comprises a furnace body, a sample transmission device, and a heating device.

[0007] The heating device and the sample transmission device are located in the furnace cavity.

[0008] One side of the furnace body is the sample inlet, and the other side is the sample outlet.

[0009] The furnace body is provided with the air inlet and the air outlet.

[0010] Optionally, the transmission mode of the sample transmission device comprises at least one of a track, a roller, a screw, and a stainless steel rod.

[0011] In the application, the sample transmission device is a super-fast sample transmission device, which can realize fast transmission of samples. The transmission can be completed in 10 seconds to 10 minutes.

[0012] Optionally, the sample inlet is used for loading samples, and the samples are transmitted in the furnace cavity by the sample transmission device and taken out from the sample outlet after sintering.

[0013] Optionally, the heating device is fixed on the inner wall of the furnace body. The fixing mode can be a conventional and general fixing mode, such as bolt connection.

[0014] In the application, the heating device and the sample transmission device are located in the furnace cavity, and their positions in the furnace body are not strictly limited. That is, as long as the heating device can provide the function of heating and the sample transmission device can transmit samples, their positions in the furnace body can be flexibly set according to actual needs.

[0015] As a specific embodiment, the heating device is arranged at the upper part of the furnace body.

[0016] As a specific embodiment, the sample transmission device is arranged at the lower part of the furnace body.

[0017] Optionally, the heating device is selected from at least one of a joule heating device, an electromagnetic heating device, an infrared heating device, and a resistance wire heating device.

[0018] Optionally, the gas inlet communicates with the gas outlet to form a gas exchange unit for replacing the atmosphere inside the furnace cavity.

[0019] Optionally, the gas inlet communicates with the gas cylinder through the gas path.

[0020] Optionally, the gas type includes but is not limited to nitrogen, argon, nitrogen-hydrogen mixed gas, and argon-hydrogen mixed gas.

[0021] Optionally, the conveying speed of the sample conveying device ranges from 0.1 to 20 m / min, and the temperature of the heating device ranges from 500 to 1400 DEG C. The speed of the sample conveying device and the sintering temperature of the heating device can be adjusted according to actual needs.

[0022] Optionally, the conveying speed of the sample conveying device ranges from 0.2 to 20 m / min.

[0023] Optionally, the size of the furnace body is 1.0-10.0 m x 0.5-3.0 m x 0.5-3.0 m. The size of the furnace body can be flexibly matched according to the amount of the key material of the retired lithium ion battery to be processed.

[0024] Optionally, the size of the furnace body is 1.0-4.0 m x 0.5-3.0 m x 0.5-3.0 m.

[0025] In the present application, the method for using the heating device includes: setting the conveying speed of the sample conveying device, the temperature of the heating device, introducing the non-active atmosphere into the furnace cavity through the gas inlet of the gas cylinder, discharging through the gas outlet, then filling the retired lithium iron phosphate positive material powder into the sample inlet, conveying in the furnace cavity through the sample conveying device, and taking out the sample from the sample outlet after sintering.

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] (1) Compared with the traditional solid-phase sintering equipment for the key material of the retired lithium ion battery, the present application can realize faster material heating, and the time cost is greatly shortened.

[0028] (2) Compared with the traditional Joule heating device, the present application can realize mass production, and the yield is greatly improved.

[0029] (3) The heating device provided by the present application can realize rapid structure repair of the retired positive material, significantly reduce the time cost and energy loss of the material regeneration process, and also realize mass production of more than one kilogram. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1A structural diagram of the heating equipment for achieving ultrafast recycling and regeneration of key materials from retired lithium-ion batteries, provided in this application;

[0031] Figure 2 A schematic diagram of the heating device for achieving ultra-fast recycling and regeneration of key materials from retired lithium-ion batteries, as provided in this application;

[0032] Figure 3 The first charge-discharge curves of a lithium iron phosphate half-cell assembled from the retired lithium iron phosphate cathode material provided in this application and the lithium iron phosphate cathode material repaired by heating equipment.

[0033] Figure 1 The accompanying diagram is labeled as follows:

[0034] 1. Furnace body; 2. Sample transfer device; 3. Heating device

[0035] 4. Sample inlet; 5. Sample outlet; 6. Air inlet

[0036] 7. Air outlet; 8. Air passage; 9. Air cylinder

[0037] 10, Sample Detailed Implementation

[0038] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0039] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0040] Unless otherwise specified, all test methods are standard and all instrument settings are those recommended by the manufacturer.

[0041] Example 1

[0042] like Figure 1 The diagram shows the structural design of a heating device for ultrafast recycling and regeneration of key materials from retired lithium-ion batteries. It includes a furnace body 1, a sample transfer device 2, and a heating device 3. Both the heating device 3 and the sample transfer device 2 are located within the furnace cavity. In this embodiment, the sample transfer device 2 is positioned at the lower part of the furnace body 1, and the heating device 3 is positioned at the upper part of the furnace body. The heating device 3 is fixed to the inner wall of the furnace body 1. A sample inlet 4 is located on the left side of the furnace body 1, and a sample outlet 5 is located on the right side of the furnace body 1. The furnace body 1 has an air inlet 6 and an air outlet 7. The air inlet 6 connects to a gas passage 8 and the air outlet 7 to form a gas exchange unit. The air inlet 6 is connected to a gas cylinder 9 via the gas passage 8. Sample 10 is filled into the sample inlet 4 and transferred within the furnace cavity via the sample transfer device 2. After sintering, the sample 10 is removed from the sample outlet 5.

[0043] Figure 2A schematic diagram of the device for the heating equipment, in which the ultrafast sample transfer device can complete the transfer in 10 seconds to 10 minutes.

[0044] Example 2: Repairing lithium iron phosphate cathode material

[0045] Collection of retired lithium iron phosphate cathode material: After the retired lithium iron phosphate battery is discharged, the package is opened, the cathode sheet is collected, and the surface residual electrolyte is washed away using ethanol and deionized water. After the active material is separated from the current collector, it is ground into powder to obtain the retired (waste) lithium iron phosphate cathode material.

[0046] Repair of retired lithium iron phosphate: 31.6 g of retired lithium iron phosphate cathode material powder is uniformly mixed with 1.47 g (about 20% iron atomic ratio) of lithium carbonate by 300 revolutions per minute for 4 hours. The mixture is placed in a stainless steel crucible, and the heating equipment of Example 1 is used. The size of the furnace body 1 is 100 cm x 50 cm x 50 cm. The sample transfer device 2 is pushed by a stainless steel rod, and the transfer speed is set to 2 m / min. The heating device 3 is a resistance wire heating device, and the temperature is set to 1000°C. The gas cylinder 9 introduces non-active atmosphere argon into the inside of the furnace cavity through the gas inlet 6, so that the sample passes through the ultrafast heating device in 30 seconds. The sample is taken out from the sample outlet 5, and the recovery of the retired lithium iron phosphate is completed.

[0047] Example 3: Repairing lithium iron phosphate cathode material

[0048] Collection of retired lithium iron phosphate cathode material: After the retired lithium iron phosphate battery is discharged, the package is opened, the cathode sheet is collected, and the surface residual electrolyte is washed away using ethanol and deionized water. After the active material is separated from the current collector, it is ground into powder to obtain the retired (waste) lithium iron phosphate cathode material.

[0049] Repair of retired lithium iron phosphate: 3160 g of retired lithium iron phosphate cathode material powder is uniformly mixed with 147 g (about 20% iron atomic ratio) of lithium carbonate by 400 revolutions per minute for 6 hours. The mixture is placed in a stainless steel crucible, and the heating equipment of Example 1 is used. The size of the furnace body 1 is 2 m x 1 m x 1 m. The sample transfer device 2 is a track, and the transfer speed is set to 2 m / min. The heating device 3 is an infrared heating device, and the temperature is set to 1100°C. The gas cylinder 9 introduces non-active atmosphere argon into the inside of the furnace cavity through the gas inlet 6, so that the sample passes through the ultrafast heating device in 60 seconds. The sample is taken out from the sample outlet 5, and the recovery of the retired lithium iron phosphate is completed.

[0050] Test Example 1

[0051] Preparation of lithium iron phosphate positive electrode tab: the repaired lithium iron phosphate of example 1, conductive agent Super P, polyvinylidene fluoride (PVDF) were mixed uniformly in a mass ratio of 8:1:1, then a proper amount of N-methyl pyrrolidone (NMP) solvent was added into the mixing tank and stirred uniformly to obtain active slurry, the active slurry was uniformly scraped on the aluminum current collector with a thickness of 15 microns, the scraping thickness was 200 microns, then the electrode tab coated with slurry was placed in a vacuum drying oven at 105°C overnight, and the electrode tab was pressed into a thickness of 60 microns by an electric roller press, and then cut into small round pieces with a diameter of 10 mm.

[0052] Assembly of lithium iron phosphate half battery: assembled and packaged in the order of stainless steel positive electrode shell, lithium iron phosphate positive electrode tab, separator, lithium negative electrode tab, gasket, spring, stainless steel negative electrode shell to prepare 2032 type button half battery, the dropwise amount of electrolyte is 30 microliters.

[0053] Electrochemical performance test of lithium iron phosphate half battery: the battery tester of Shenzhen Xinweier Electronics Co., Ltd. was used to test the discharge capacity of the battery, the current used for testing was 0.1C, and the voltage range was 2.4 to 4.2V.

[0054] Analysis of the electrochemical performance test results of example 1:

[0055] It can be seen from Figure 3 that the specific capacity of the first circle of the repaired lithium iron phosphate of example 1 is restored to 150.6 mAh / g at low rate (0.1C) charging, and the discharge specific capacity is restored to 150.2 mAh / g. It reaches the discharge standard of commercial lithium iron phosphate positive electrode, which indicates that the damaged structure of the retired lithium iron phosphate has been completely repaired, and the crystal lattice has been lithiated.

[0056] As can be seen from the above, using the heating device of the present application can realize the recycling of retired lithium iron phosphate positive electrode material of more than ten kilograms or even kilograms, and the recycling time can be completed in a short time. The repaired lithium iron phosphate positive electrode material after the heating device can be completely repaired, and reaches the discharge standard of commercial lithium iron phosphate positive electrode.

[0057] The above is only a few embodiments of the present application, and does not limit the present application in any form. Although the above is disclosed as a preferred embodiment, it is not intended to limit the present application. Any skilled person in the art can make some changes or modifications to the above disclosed technical content without departing from the scope of the technical solution of the present application, which are equivalent to equivalent embodiments, and all belong to the scope of the technical solution.

Claims

1. A heating device for realizing ultrafast recycling of key materials of retired lithium-ion batteries, characterized in that, The heating device comprises a furnace body, a sample transmission device and a heating device; The heating device and the sample transmission device are located in a furnace cavity; One side of the furnace body is a sample inlet and the other side is a sample outlet; The furnace body is provided with an air inlet and an air outlet.

2. The heating apparatus of claim 1, wherein The sample transmission device comprises at least one of a caterpillar belt, a roller, a screw rod and a stainless steel rod.

3. The heating apparatus of claim 1, wherein, The sample inlet is used to fill the sample, which is transmitted in the furnace cavity by the sample transmission device and taken out from the sample outlet after sintering.

4. The heating apparatus of claim 1, wherein, The heating device is fixed on the inner wall of the furnace body.

5. The heating apparatus of claim 1, wherein, The heating device is arranged at the upper part of the furnace body. The sample transmission device is arranged at the lower part of the furnace body.

6. The heating apparatus of claim 1, wherein, The heating device is selected from at least one of a Joule heating device, an electromagnetic heating device, an infrared heating device and a resistance wire heating device.

7. The heating apparatus of claim 1, wherein The air inlet, the air path and the air outlet form a gas exchange unit for replacing the atmosphere in the furnace cavity.

8. The heating apparatus of claim 1, wherein, The air inlet is connected with the gas cylinder through the air path.

9. The heating apparatus of claim 1, wherein, The transmission speed of the sample transmission device ranges from 0.1 to 20 m / min, and the temperature of the heating device ranges from 500 to 1400℃.

10. The heating apparatus of claim 1, wherein, The size of the furnace body is 1.0-10.0 m in length, 0.5-3.0 m in width and 0.5-3.0 m in height.

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