A pretreatment system for lithium battery recycling

Abstract

The utility model proposes a pretreatment system for lithium battery recycling, including: an insulation box, a cutting device, a vibrating screen device, a spray pipeline and a component recovery device; the insulation box is used to provide a constant temperature closed environment for the lithium battery to stabilize the state of the contents of the lithium battery; the vibrating screen device is arranged outside the insulation box, and the vibrating screen device is used to drive the contents of the lithium battery to flow out of the notch of the lithium battery; the cutting device is arranged inside the insulation box, and the spray pipeline is arranged around the outer periphery of the cutting device, and the spray pipeline is used to clean the lithium battery after being processed by the vibrating screen device; the component recovery device is connected to the discharge port of the insulation box to extract and purify the contents of the lithium battery. The utility model pre-treats and separates the liquid or easily liquefied organic or inorganic substances in the lithium battery while ensuring that the outer shell of the lithium battery, the internal diaphragm, the positive and negative electrodes, etc. are relatively intact, thereby laying a foundation for the subsequent battery classification, repair and recycling, and thus improving the economic benefits of the entire lithium battery recycling.

Description

Technical Field

[0001] The utility model belongs to the technical field of lithium battery recycling, and in particular relates to a pretreatment system for lithium battery recycling. Background Art

[0002] Lithium battery energy storage is an electrochemical energy storage technology. Battery energy storage has more advantages in scalability, service life, flexibility, etc. Its use is not limited by geographical conditions, and it can also be used as an auxiliary facility for the power grid. Therefore, the world is currently actively developing lithium battery energy storage technology. With the promotion and application of energy storage and electric vehicles, the advent of the power battery retirement cycle, a large number of waste power batteries face recycling and treatment problems. If they cannot be effectively recycled and treated, it will not only cause a waste of resources, but also cause certain pollution to the environment.

[0003] Lithium battery recycling mostly uses airflow gravity separation method, which grinds the battery into small powders and separates different components by gravity. However, this method cannot recycle undamaged recyclable parts separately during use. After these parts are crushed and ground, it is more difficult to separate the components later. On the other hand, the more components in the mixture, the greater the energy consumption during separation.

[0004] However, some components can be repaired and reused, while direct crushing and recycling will cause energy loss. Moreover, the more mixed components there are, the more difficult it is to control the purity of the separated components. The highly active components are more likely to cause environmental pollution or explosion. How to improve the economic effect of the entire lithium battery recycling is an important research direction for lithium battery recycling. Utility Model Content

[0005] In order to solve the problem that the prior art described in the background technology cannot recycle undamaged parts separately, the utility model proposes the following technical solution:

[0006] A pretreatment system for lithium battery recycling, comprising: an insulation box, a cutting device, a vibrating screen device, a spray pipeline and a component recovery device; the interior of the insulation box is respectively connected to the spray pipeline and the exhaust gas treatment device, and the insulation box is used to provide a constant temperature closed environment for the lithium battery to stabilize the state of the contents of the lithium battery; the vibrating screen device is arranged on the outside of the insulation box, and the vibrating screen device is used to drive the contents of the lithium battery to flow out of the notch of the lithium battery; the cutting device is arranged in the insulation box, the spray pipeline is arranged around the outer periphery of the cutting device, and the spray pipeline is used to clean the lithium battery after being processed by the vibrating screen device; the component recovery device is connected to the discharge port of the insulation box to extract and purify the contents of the lithium battery.

[0007] Furthermore, the pretreatment system also includes an inert gas generator; the inert gas generator is connected to the incubator, and the inert gas generator is used to dry and activate the lithium battery after the lithium battery is cleaned.

[0008] Furthermore, the exhaust gas treatment equipment includes: a blower, an exhaust duct, an absorption device and a purification device; the blower is connected to the input port of the insulation box; the input end of the exhaust duct is respectively connected to the exhaust port of the insulation box and the exhaust port of the component recovery device, and the output end of the exhaust duct is connected to the absorption device; the output port of the absorption device is connected to the input port of the purification device.

[0009] Furthermore, an alkaline solution is provided in the absorption device, and an aqueous solution is provided in the purification device.

[0010] Furthermore, one end of the input port in the absorption device is deep below the liquid surface of the alkaline solution, and one end of the output port of the absorption device is located above the liquid surface of the alkaline solution; one end of the input port of the purification device is deep below the liquid surface of the aqueous solution.

[0011] Furthermore, a solenoid valve is provided at the input end of the exhaust pipe.

[0012] Beneficial effects: The utility model pre-treats and separates liquid or easily liquefied organic or inorganic matter in lithium batteries while ensuring that the outer shell of the lithium battery, the internal diaphragm, the positive and negative electrodes, etc. are relatively intact, thereby laying the foundation for subsequent battery classification, repair and recycling, and further improving the economic benefits of the entire lithium battery recycling. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a flow chart of a pretreatment method for lithium battery recycling according to an embodiment of the utility model;

[0014] Figure 2 The figure is a schematic diagram of the structure of a pretreatment system for lithium battery recycling according to an embodiment of the utility model. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solution and advantages of the present application clearer, the present invention will be described in further detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0016] It should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this patent and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this patent.

[0017] Figure 1 The present invention is a flowchart of a pretreatment method for recycling lithium batteries according to an embodiment of the present invention.

[0018] Reference Figure 1 According to an embodiment of the present invention, a pretreatment method for lithium battery recycling includes:

[0019] S000, discharging the lithium battery.

[0020] Specifically, in this step, the residual power in the lithium battery is discharged by using a dedicated discharge device to avoid accidents during subsequent processing. After the lithium battery is discharged, the operator places it in a closed environment with a constant temperature for further processing.

[0021] S010. A notch is formed on the surface of the lithium battery in a closed environment at a constant temperature.

[0022] Specifically, in this step, in order to maintain the physical state of the contents of the lithium battery (such as electrolyte solution, current collector, etc.), a device with a constant temperature function such as an incubator 1 is used to create a constant temperature closed environment for the recycling of lithium batteries in advance. In this closed environment, the temperature is set to any value between 20° and 45°. In addition, in the process of notching the surface of the lithium battery, the exhaust gas generated by the lithium battery needs to be processed to prevent accidents during the notching of the surface of the lithium battery. For the convenience of description, the following closed environment is described using the incubator 1 as an example.

[0023] Preferably, in this embodiment, the notch opened on the surface of the lithium battery is located on any narrow surface of the lithium battery, and the width of the notch is between 1 mm and 2 mm, so as to facilitate subsequent recycling and repair. After the notch opening operation is completed, the lithium battery is fixed in the thermal insulation box 1 with the notch facing downward, so as to ensure that the contents of the lithium battery can fully flow out.

[0024] S020. Perform vibration screening on the lithium battery and collect the contents of the lithium battery.

[0025] Specifically, in this step, the operator oscillates the incubator 1 through the vibrating device 3, so that the contents of the lithium battery (such as electrolyte solution, positive electrode, negative electrode, separator and current collector, etc.) flow out of the lithium battery. In the above process, the contents of the lithium battery flow into the component recovery device 5 below the incubator 1 with the action of the oscillating device.

[0026] S030. Clean the lithium battery and recover the cleaning fluid.

[0027] Specifically, in this step, the volume ratio of ethanol in the cleaning liquid is between 0% and 10%, which is determined according to the type of lithium battery. Since part of the battery content is dissolved by the cleaning liquid during the cleaning process, the cleaning liquid effectively adsorbs and precipitates volatile organic matter, inorganic salts or acidic substances in the process, so the cleaning liquid in the process also needs to be recycled and processed.

[0028] S040, Recycling and repairing lithium batteries with complete performance.

[0029] Specifically, after the lithium battery is cleaned, it is necessary to perform a drying and deactivation treatment. During this process, the cleaning pipeline 4 inside the insulated box 1 needs to be cleaned twice. Among them, the cleaning pipeline 4 includes a first branch and a second branch, the first branch is located on the inner surface of the top cover of the insulated box 1, and the second branch is located on the outer peripheral surface of the cutting device 2. Specifically, after the vibrating screen equipment stops starting, the first branch and the second branch respectively spray cleaning fluid into the interior of the lithium battery, thereby cleaning the remaining contents inside the lithium battery. During the first cleaning process, the second branch stops after 2 minutes to 5 minutes, and the first branch 41 stops spraying after 30 seconds to 2 minutes. Among them, the two branches start spraying at the same time, and the concentration of ethanol in the cleaning fluid of the two branches is equal, both 0% to 10%.

[0030] During the first cleaning process, when the second branch 42 stops spraying, the second cleaning begins. The second cleaning ends after only the first branch 41 sprays the cleaning solution containing ethanol for 5 seconds, and the second branch does not spray, so as to provide an environment for the rapid drying of the lithium battery. After the second cleaning, hot air is blown into the incubator 1 for 20 minutes, and the hot air is simultaneously blown into the inert gas for 10 minutes to passivate the inner and outer surfaces of the lithium battery.

[0031] The inert gas includes but is not limited to helium, neon or nitrogen. After drying, the lithium battery only has the outer shell and the positive electrode material, negative electrode material and diaphragm inside. If the electrical performance is found to be intact, it can be directly recycled for repair; if the electrical performance is found to be incomplete, it will be further recycled.

[0032] At this point, the pretreatment of the outer shell of the lithium battery is completed. Among them, the test involves separate performance tests of each component such as the positive electrode and the negative electrode, including but not limited to tests such as electrochemical performance, thermal stability, conductivity, etc. that are required after conventional battery production. The specific process flow of the relevant tests is a mature existing technology and will not be repeated here.

[0033] S050, extracting and purifying the content with the cleaning solution, so as to recover the components of each layer after standing and stratifying.

[0034] Specifically, in this step, the contents flowing out of the notch of the lithium battery and the cleaning liquid flowing out from the lithium battery contain a large amount of high-value metal substances, and the surfaces of the graphite and other substances flowing out will adsorb some of the metal components. During the cleaning process, the cleaning liquid flows into the component recovery device 5 along with the discharge port of the thermal insulation box 1, and the cleaning liquid and the contents are stirred and mixed together after the component recovery device 5 is started. In this process, the metal components adsorbed by graphite and other substances are extracted by the cleaning liquid to improve the recovery rate. Preferably, in this step, an additional spraying device can be provided in the component recovery device 5 to clean the cleaning liquid adhering to the inner wall of the component recovery device 5 during the stirring process.

[0035] After static precipitation, each component is layered in the component recovery device 5. The components of each layer are specifically solid graphite in the bottom layer, water-soluble salt in the middle layer, and organic matter in the upper layer. The operator recycles each layer through the corresponding process to achieve the maximum effect of lithium battery recycling. At this point, the recovery pretreatment of the contents of the lithium battery is completed.

[0036] In order to further describe the utility model, different types of lithium batteries are selected to illustrate the entire pre-recycling method. Wherein, when the cleaning liquid is ethanol, the volume percentage of ethanol is 10%.

[0037] Example 1: Recycling pretreatment of soft-pack ternary lithium batteries.

[0038] The soft-pack ternary lithium battery is fully discharged using a dedicated charging and discharging device. The temperature in the insulation layer box is set to 45°C to create a closed constant temperature environment, and the waste gas in the insulation box 1 is treated by the waste gas recovery equipment. Each soft-pack ternary lithium battery in the insulation box 1 is placed vertically inside the insulation box 1, and is punctured by the cutting device 2 in the insulation box 1 to open a 1mm wide notch on the narrow side of the bottom of each soft-pack ternary lithium battery.

[0039] After the notch is opened on the surface of the soft-pack ternary lithium battery, the vibration screening device 3 is turned on for ten minutes, and the liquid organic matter, part of the inorganic salt and the acidic substance in the soft-pack ternary lithium battery flow into the component recovery device 5 through the discharge port of the insulation box 1. After the vibration screening is completed, the soft-pack ternary lithium battery is cleaned, wherein the volume ratio of ethanol in the cleaning liquid used is 10%. After cleaning for ten minutes, the first branch 41 of the top cover of the insulation box 1 is opened to spray the ethanol solution for 5 seconds, nitrogen is introduced for 5 minutes and a 45° hot air purge is set for 5 minutes at the same time, the soft-pack ternary lithium battery is dried and deactivated, and the soft-pack ternary lithium battery with complete electrical performance is recovered. The component recovery device 5 is turned on to mix and stir the substances of each component and the recovered cleaning liquid, and after ten minutes, the mixture inside is left to stand and stratify, and the components of each layer are recovered in turn. Among them, the bottom layer is graphite and solid electrolyte EC, the middle layer is an aqueous solution (mainly lithium salt, a small amount of nickel cobalt manganese salt), and the upper layer is organic matter, such as DMC, PC (PG), etc. The materials of each component will be further deeply recovered later.

[0040] Example 2: Recycling pretreatment of aluminum shell ternary lithium batteries.

[0041] The aluminum shell ternary lithium battery is fully discharged using a dedicated charging and discharging device. The temperature in the insulation layer box is set to 20°C to create a closed constant temperature environment, and the waste gas in the insulation box 1 is treated by the waste gas recovery equipment. Each aluminum shell ternary lithium battery in the insulation box 1 is placed vertically inside the insulation box 1, and is punctured by the cutting device 2 in the insulation box 1 to open a 1mm wide notch on the narrow side of the bottom of each aluminum shell ternary lithium battery.

[0042] After the notch is opened on the surface of the aluminum shell ternary lithium battery, the vibration screening device 3 is turned on for thirty minutes, and the liquid organic matter, some inorganic salts and acidic substances in the aluminum shell ternary lithium battery flow into the component recovery device 5 through the discharge port of the insulation box 1. After the vibration screening is completed, the aluminum shell ternary lithium battery is cleaned, wherein the clean cleaning liquid used is water. After five minutes of cleaning, the first branch 41 is opened in the insulation box 1 to spray ethanol for 10 seconds, helium is introduced for 10 minutes, and a 20° hot air purge is set for 5 minutes at the same time, the aluminum shell ternary lithium battery is dried and deactivated, and the aluminum shell ternary lithium battery with complete electrical performance is recovered. The component recovery device 5 is turned on to mix and stir the substances of each component and the recovered cleaning liquid, and after twenty minutes, the mixture inside is left to stand and stratify, and the components of each layer are recovered in turn. Among them, the bottom layer is graphite and solid electrolyte EC, the middle layer is an aqueous solution (mainly lithium salt, a small amount of nickel cobalt manganese salt), and the upper layer is organic matter, such as DMC, PC, etc. The substances of each component are further recovered in depth later.

[0043] Example 3: Recycling pretreatment of steel-cased lithium iron phosphate batteries.

[0044] The steel-shelled ternary lithium iron phosphate battery is fully discharged using a dedicated charging and discharging device. The temperature in the insulation layer box is set to 25°C to create a closed constant temperature environment, and the waste gas in the insulation box 1 is treated by the waste gas recovery equipment. Each steel-shelled ternary lithium iron phosphate battery in the insulation box 1 is placed vertically inside the insulation box 1, and is punctured by the cutting device 2 in the insulation box 1 to open a notch with a width of 2 mm on the narrow side of the bottom of each steel-shelled ternary lithium iron phosphate battery.

[0045] After the notch is opened on the surface of the steel shell iron phosphate ternary lithium battery, the vibration screening device 3 is turned on for fifteen minutes, and the liquid organic matter, some inorganic salts and acidic substances in the steel shell iron phosphate ternary lithium battery flow into the component recovery device 5 through the discharge port of the insulation box 1. After the vibration screening is completed, the steel shell iron phosphate ternary lithium battery is cleaned, wherein the cleaning liquid used is water. After five minutes of cleaning, the first branch 41 is opened in the insulation box 1 to spray ethanol for 8 seconds. Helium is introduced for 10 minutes and a 20° hot air purge is set for 5 minutes at the same time to dry and deactivate the steel shell iron phosphate ternary lithium battery, and the steel shell iron phosphate ternary lithium battery with complete electrical performance is recovered. The component recovery device 5 is turned on to mix and stir the substances of each component and the recovered cleaning liquid, and after twenty minutes, the mixture inside is left to stand and stratify, and the components of each layer are recovered in turn. Among them, the bottom layer is graphite and solid electrolyte EC, the middle layer is an aqueous solution (mainly lithium salt, a small amount of nickel cobalt manganese salt), and the upper layer is organic matter, such as DMC, DEC, MA, etc. The materials of each component will be further deeply recovered later.

[0046] Figure 2 The figure is a schematic diagram of the structure of a pretreatment system for lithium battery recycling according to an embodiment of the utility model.

[0047] Reference Figure 2 Another object of the utility model is to propose a pretreatment system applied to the above-mentioned pretreatment method, comprising: an insulation box 1, a cutting device 2, a vibrating screen device 3, a spray pipeline 4 and a component recovery device 5. The interior of the insulation box 1 is respectively connected to the spray pipeline 4 and the exhaust gas treatment device, and the insulation box 1 is used to provide a constant temperature closed environment for the lithium battery to stabilize the state of the contents of the lithium battery. The vibrating screen device 3 is arranged on the outside of the insulation box 1, and the vibrating screen device 3 is used to drive the contents of the lithium battery to flow out of the notch of the lithium battery. The cutting device 2 is arranged in the insulation box 1, and the spray pipeline 4 is arranged around the outer periphery of the cutting device 2, and the spray pipeline 4 is used to clean the lithium battery after being treated by the vibrating screen device 3. The component recovery device 5 is connected to the unloading buckle of the insulation box 1 to extract and purify the contents of the lithium battery.

[0048] Furthermore, the pretreatment system also includes an inert gas generator 7. The inert gas generator 7 is connected to the interior of the incubator 1. After the lithium battery in the incubator 1 is cleaned, the inert gas generator 7 delivers an inert gas of a set temperature into the incubator 1. The spray pipeline includes a first branch 41 located on the top cover of the incubator and a second branch 42 located on the periphery of the cutting device 2. During the cleaning process, the first branch 41 and the second branch 42 work together. The first branch 41 is mainly used to clean the inner wall of the incubator and prevent gas from overflowing, and the second branch 42 is mainly used to clean the inside of the lithium battery.

[0049] Specifically, the exhaust gas treatment equipment includes: a blower 61, an exhaust pipe 62, an absorption device 63 and a purification device 64. The blower 61 is connected to the input port of the incubator 1 through the blowing pipe, thereby driving the gas flow inside the incubator 1. The input port of the exhaust pipe 62 is respectively connected to the input port of the exhaust port of the incubator and the exhaust port of the component recovery device 5, and the output end of the exhaust pipe 62 is connected to the input port of the absorption device 63. The output port of the absorption device 63 is connected to the input port of the purification device 64. Furthermore, each input end of the exhaust pipe 62 is provided with a solenoid valve 621, and each solenoid valve 321 is opened alternately. After the pretreatment starts, the solenoid valve 621 located in a section of the exhaust pipe 62 connected to the exhaust port of the incubator 1 is continuously opened until the operator completes the recovery and repair of the lithium battery with complete performance. When the operator completes the recovery and repair of lithium batteries with complete performance, the solenoid valve 621 located at a section of the exhaust pipe 62 connected to the exhaust port of the incubator 1 is closed, and the battery valve 621 located at a section of the exhaust pipe 62 connected to the exhaust port of the component recovery device 5 is opened, so as to continuously treat the waste gas generated during the pretreatment process.

[0050] Among them, an alkaline solution is provided in the absorption device 63, and an aqueous solution is provided in the purification device 64. The solutes of the alkaline solution include but are not limited to alkaline substances such as sodium hydroxide, potassium hydroxide or sodium bicarbonate. The absorption device 63 and the purification device 64 are both dual-port devices, wherein one end of the input port of the absorption device 63 is deep below the liquid surface of the alkaline solution, and the output port of the absorption device 63 is located above the liquid surface of the alkaline solution. One end of the input port of the purification device 64 is deep below the liquid surface of the aqueous solution, and the output port of the purification device 64 is located above the liquid surface of the aqueous solution. When the exhaust gas in the insulation box 1 is treated, the blower 61 continuously supplies air to drive the exhaust gas in the insulation box 1 to be input into the absorption device 63, and the exhaust gas reacts with the alkaline solution in the absorption device 63 to remove harmful substances in the exhaust gas.

[0051] In summary, the utility model pre-treats and separates liquid or easily liquefied organic or inorganic matter in lithium batteries by ensuring that the outer shell of the lithium battery, the internal diaphragm, the positive and negative electrodes, etc. are relatively intact, thereby laying the foundation for subsequent battery classification, repair and recycling, and further improving the economic benefits of the entire lithium battery recycling.

[0052] The above description is of certain embodiments of the invention. Other embodiments are within the scope of the following claims.

[0053] The terms "exemplary," "example," and the like used throughout this specification mean "used as an example, instance, or illustration" and do not mean "preferred" or "advantageous" over other embodiments. The detailed description includes specific details for the purpose of providing an understanding of the described techniques. However, these techniques can be implemented without these specific details. In some instances, in order to avoid obscuring the concepts of the described embodiments, well-known structures and devices are shown in block diagram form.

[0054] The optional implementation modes of the embodiments of the utility model are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the utility model are not limited to the specific details in the above implementation modes. Within the technical concept of the embodiments of the utility model, the technical scheme of the embodiments of the utility model can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the embodiments of the utility model.

[0055] The above description of the contents of this specification is provided to enable any person of ordinary skill in the art to implement or use the contents of this specification. Various modifications to the contents of this specification will be apparent to those of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of protection of the contents of this specification. Therefore, the contents of this specification are not limited to the examples and designs described herein, but are consistent with the widest range of principles and novel features disclosed herein.

Claims

1. A pretreatment system for lithium battery recycling, characterized in that: include: An insulation box (1), a cutting device (2), a vibrating screen device (3), a spray pipeline (4) and a component recovery device (5); the interior of the insulation box (1) is respectively connected to the spray pipeline (4) and the exhaust gas treatment device (6); the insulation box (1) is used to provide a constant temperature closed environment for the lithium battery to stabilize the state of the contents of the lithium battery; the vibrating screen device (3) is arranged outside the insulation box (1), and the vibrating screen device (3) is used to drive the contents of the lithium battery to flow out of the notch of the lithium battery; the cutting device (2) is arranged in the insulation box (1), the spray pipeline (4) is arranged around the outer periphery of the cutting device (2), and the spray pipeline (4) is used to clean the lithium battery after being treated by the vibrating screen device (3); the component recovery device (5) is connected to the discharge port of the insulation box (1) to extract and purify the contents of the lithium battery.

2. A pretreatment system for lithium battery recycling according to claim 1, characterized in that: The pretreatment system further comprises an inert gas generator (7); the inert gas generator (7) is connected to the heat preservation box (1), and the inert gas generator (7) is used to dry and activate the lithium battery after the lithium battery is cleaned.

3. A pretreatment system for lithium battery recycling according to claim 2, characterized in that: The exhaust gas treatment equipment (6) comprises: a blower (61), an exhaust pipe (62), an absorption device (63) and a purification device (64); the blower (61) is connected to the input port of the insulation box (1); the input end of the exhaust pipe (62) is respectively connected to the exhaust port of the insulation box (1) and the exhaust port of the component recovery device (5), and the output end of the exhaust pipe (62) is connected to the absorption device (63); the output port of the absorption device (63) is connected to the input port of the purification device (64).

4. A pretreatment system for lithium battery recycling according to claim 3, characterized in that: The absorption device (63) is provided with an alkaline solution, and the purification device (64) is provided with an aqueous solution.

5. A pretreatment system for lithium battery recycling according to claim 4, characterized in that: One end of the input port in the absorption device (63) is located below the liquid surface of the alkaline solution, and one end of the output port of the absorption device (63) is located above the liquid surface of the alkaline solution; one end of the input port of the purification device (64) is located below the liquid surface of the aqueous solution.

6. A pretreatment system for lithium battery recycling according to claim 3, characterized in that: The input end of the exhaust pipe (62) is provided with a solenoid valve (621).

Images