Waste lithium battery disassembling method

Abstract

The invention discloses a method for disassembling a waste lithium battery. The method comprises the following steps: S1, discharging the waste lithium battery; s2, carrying out voltage testing on the lithium battery subjected to discharging treatment; s3, performing puncture treatment on the lithium battery which is qualified in the voltage test; s4, disassembling the battery subjected to puncture treatment to form a waste material and a battery cell 13; s5, waste materials generated in the disassembling process are subjected to recycling treatment; s6, core pushing treatment is carried out on the disassembled lithium battery, shell pressing recovery treatment is carried out on waste materials such as shells disassembled from the lithium battery, the waste materials are temporarily stored in a shell temporary storage box 20, and disassembled roll cores 13 enter a roll core temporary storage bin 16 to be temporarily stored; and step S7, manually separating positive and negative pole pieces and a diaphragm from the temporarily stored roll core 13. According to the invention, the waste lithium battery can be accurately disassembled to respectively obtain positive and negative pole pieces, diaphragms and shells, and the subsequent treatment process of further sorting positive and negative pole powder and copper and aluminum is simplified.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery disassembly, and in particular to a method for disassembling waste lithium batteries. Background Art

[0002] In the prior art, the disassembly methods of waste lithium batteries are usually manual disassembly and mechanical crushing. During the manual disassembly process, the electrolyte in the waste lithium batteries is likely to flow out, and the volatilization of the electrolyte will produce irritating gases. Long-term manual inhalation of the irritating gases produced by the volatilization of the electrolyte will seriously damage the health of the body, and the manual disassembly efficiency is low. Conventional mechanical crushing will produce a large amount of toxic gases and dust, causing pollution to the environment.

[0003] In the prior art, waste lithium batteries are discharged before being disassembled. During the batch discharging process, the power in the batteries may not be completely discharged. In addition, during the disassembly process, once sparks generated during the cutting process come into contact with the electrolyte, the battery cells in the battery may ignite, thereby causing a fire. Therefore, there are certain safety hazards in the existing disassembly process of waste lithium batteries. Summary of the invention

[0004] The present invention proposes a method for disassembling waste lithium batteries, which can achieve accurate disassembly of waste lithium batteries on the basis of avoiding manual disassembly, obtain complete positive and negative electrode sheets, and collect and process the electrolyte to avoid its influence on the subsequent sorting process. At the same time, the method of directly crushing and sorting lithium batteries is not used, the loss of black powder is reduced, the recycling process is simplified, the grade of black powder recovery is improved, the economic benefits are increased, the recycling cost is reduced, and the effect of efficient and green disassembly of lithium batteries is achieved.

[0005] The technical solution of the present invention is achieved in this way:

[0006] A method for disassembling waste lithium batteries, comprising:

[0007] Step S1, discharging the waste lithium battery;

[0008] Step S2, performing a voltage test on the lithium battery after the discharge process;

[0009] Step S3, puncturing the lithium battery that has passed the voltage test;

[0010] Step S4, disassembling the punctured battery to form waste materials and battery cells;

[0011] Step S5, recycling the waste generated during the disassembly process;

[0012] Step S6, the disassembled lithium battery is subjected to core pushing treatment, the shell and other waste materials of the disassembled lithium battery are subjected to shell compression recovery treatment and temporarily stored in the shell temporary storage box, and the disassembled core is temporarily stored in the core temporary storage warehouse;

[0013] In step S7, the temporarily stored winding core can be manually separated into positive and negative electrode sheets and separators.

[0014] Preferably, the steps of step S1 are specifically as follows:

[0015] Connect the discharge meter to the positive and negative poles of the battery cell to consume the remaining power of the battery cell in the form of heat energy. The voltage is required to be less than 1V during the discharge process.

[0016] Preferably, the steps of step S2 are specifically as follows:

[0017] Use a voltage detector to test the voltage, use a positioning push rod to fix the discharged battery cell at the set position, and connect the copper plate at the output end of the voltage detector to the battery cell ear end to test the residual voltage of the battery cell.

[0018] Preferably, the steps of step S3 are specifically as follows:

[0019] After the battery cell is fixed to the set position below the puncturing knife by the positioning push rod 2, the puncturing knife moves down to the top of the battery cell and cuts the outer shell of the battery cell according to the set depth to complete the puncturing action; after the puncturing action is completed, the battery cell is pushed out of the puncturing station and transported forward to the shaping station by the belt conveyor equipment 1. The side shaping push rod and the top shaping push rod on the shaping station squeeze the battery cell from the side and top at the same time to complete the shaping process.

[0020] Preferably, the steps of step S4 are specifically as follows:

[0021] The tab end of the battery cell is taken as the A side, the opposite side of the tab end is taken as the B side, and the left or right side of the battery cell is taken as the C side. During the disassembly process, the A side is cut first, then the B side is cut after cutting the A side, and finally the C side is cut.

[0022] Preferably, the A surface, the B surface and the C surface may be cut by pressing, grinding or sawing.

[0023] Preferably, in step S5, the waste materials to be collected include the completely cut A and B surfaces, and the debris generated when cutting the C surface.

[0024] Preferably, the steps of step S6 are specifically as follows:

[0025] Positioning push rod three fixes the battery cell after three-side cutting. The core pushing plate separates the core and the shell under the push of the discharging push rod. Positioning push rod three fixes the two sides of the battery cell. The core pushing plate pushes the core out from side A or side B. The core pushed out from the core pushing station is transported to the core storage box for closed treatment through belt conveyor equipment two. The shell coming out of the core pushing processing station is transported to the shell pressing station by belt conveyor equipment two. When it reaches the set position, positioning push rods four on both sides fix the shell. A shell pressing push rod is provided above this position to flatten the shell, reduce the volume of the shell, and transport it to the shell storage box through the conveyor belt.

[0026] Preferably, in step S7, during the separation process, the core does not come into direct contact with the staff, and the process is carried out in a glove box.

[0027] Preferably, in the above-mentioned steps S3, S4 and S6, during the treatment process where waste gas may be generated and electrolyte volatilization may occur, closed treatment and inert gas protection are required, that is, each workstation is equipped with nitrogen nozzles and detection equipment such as temperature sensors and oxygen sensors. When risks such as abnormal ignition temperature occur, the sensor transmits a signal to the central control room, and the nitrogen nozzle can be automatically opened to spray nitrogen to the abnormal temperature location.

[0028] Beneficial effects:

[0029] The present invention can accurately disassemble waste lithium batteries to obtain positive and negative electrode sheets, diaphragms and shells respectively, thereby simplifying the subsequent processing process of further sorting positive and negative electrode powders and copper and aluminum;

[0030] The present invention uses automatic disassembly equipment to disassemble waste lithium batteries, and its disassembly efficiency is much higher than manual disassembly and safety is also higher;

[0031] The present invention can perform closed treatment on the links that may generate waste gas, making the disassembly process safer and more environmentally friendly;

[0032] Compared with direct crushing and sorting, the precise disassembly method of the present invention has a simpler process, a higher product quality, and generates almost no dust during the disassembly process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 Schematic diagram of a method for disassembling waste lithium batteries according to an embodiment of the present invention Figure 1 ;

[0035] Figure 2 Schematic diagram of a method for disassembling waste lithium batteries according to an embodiment of the present invention Figure 2 ;

[0036] Figure 3 Schematic diagram of a method for disassembling waste lithium batteries according to an embodiment of the present invention Figure 3 ;

[0037] Figure 4 Schematic diagram of a method for disassembling waste lithium batteries according to an embodiment of the present invention Figure 4 ;

[0038] Figure 5 is a schematic diagram of a battery cell structure according to a method for disassembling a waste lithium battery according to an embodiment of the present invention;

[0039] Figure 6 The present invention is a flowchart of a method for disassembling waste lithium batteries according to an embodiment of the present invention.

[0040] In the figure,

[0041] 1. Voltage detector; 2. Battery cell; 3. Positive electrode tab; 4. Negative electrode tab; 5. Positioning push rod one; 6. Copper plate; 7. Positioning push rod two; 8. Piercing knife; 9. Side shaping push rod; 10. Positioning push rod three; 11. Push core plate; 12. Discharging push rod; 13. Winding core; 14. Belt conveyor equipment two; 15. Belt conveyor equipment one; 16. Winding core temporary storage box; 17. Shell pressing station; 18. Positioning push rod four; 19. Shell pressing push rod; 20. Shell temporary storage box; 21. Top shaping push rod. DETAILED DESCRIPTION

[0042] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0043] According to an embodiment of the present invention, a method for disassembling waste lithium batteries is provided.

[0044] like Figure 1-Figure 6 As shown, in this optional embodiment, the method for disassembling waste lithium batteries according to an embodiment of the present invention includes:

[0045] Step S1, discharging the waste lithium battery;

[0046] Step S2, performing a voltage test on the lithium battery after the discharge process;

[0047] Step S3, puncturing the lithium battery that has passed the voltage test;

[0048] Step S4, disassembling the punctured battery to form waste materials and battery cells 13;

[0049] Step S5, recycling the waste generated during the disassembly process;

[0050] Step S6, the disassembled lithium battery is subjected to core pushing processing, the shell and other waste materials of the disassembled lithium battery are subjected to shell compression recovery processing and temporarily stored in the shell temporary storage box 20, and the disassembled winding core 13 is temporarily stored in the winding core temporary storage bin 16;

[0051] In step S7, the temporarily stored winding core 13 can be manually separated into positive and negative electrode sheets and separators.

[0052] In this optional embodiment, the steps of step S1 are specifically as follows:

[0053] The waste lithium battery can be discharged using a high current discharge method. The high current discharge method is similar to the voltage detection method. The discharger is connected to the positive electrode tab 3 and the negative electrode tab 4 of the battery cell 2 to consume the remaining power of the battery cell 2 in the form of heat energy. The voltage during the discharge process is required to be lower than 1V, that is, the lithium battery voltage after discharge is lower than 1V.

[0054] In this optional embodiment, the steps of step S2 are specifically as follows:

[0055] Use the voltage detector 1 to detect the voltage, use the positioning push rod 5 device to fix the discharged battery cell 2 at the set position, connect the copper plate 6 at the output end of the voltage detector 1 with the ear end of the battery cell 2 to test the residual voltage of the battery cell 2. The purpose of the voltage test link is to exclude the battery cells whose voltage rises to more than 1V after the discharge treatment, so as to avoid the danger of short circuit in the subsequent disassembly process.

[0056] In this optional embodiment, the steps of step S3 are specifically as follows:

[0057] After the battery cell 2 is fixed to the set position below the puncturing knife 8 by the positioning push rod 27, the puncturing knife 8 moves down to the top of the battery cell 2, cuts the outer shell of the battery cell 2 according to the set depth, and completes the puncturing action; after completing the puncturing action, the battery cell 2 is pushed out of the puncturing station and transported forward to the shaping station by the belt conveyor equipment 15. The side shaping push rod 9 and the top shaping push rod 21 on the shaping station squeeze the inside of the battery cell 2 from the side and the top at the same time to complete the shaping process, and the gasified electrolyte and a part of the liquid electrolyte are squeezed out by the puncturing method. At the same time, the lithium battery that is bulging or has changed shape after discharge is regularized to make its shape more regular and easier to disassemble later. When the lithium battery that has passed the voltage test is punctured, only the outer shell of the lithium battery is punctured during the puncturing process.

[0058] In this optional embodiment, the steps of step S4 are specifically as follows:

[0059] The tab end of the battery cell 2 is taken as the A side, the opposite side of the tab end is taken as the B side, and the left or right side of the battery cell 2 is taken as the C side. During the disassembly process, the A side is cut first, then the B side is cut, and finally the C side is cut. The purpose of cutting the C side is to make the subsequent core pushing process smoother. Therefore, when cutting the C side, it is not necessary to cut the C side completely.

[0060] In this optional embodiment, the A surface, the B surface and the C surface may be cut by pressing, grinding or sawing.

[0061] In this optional embodiment, in step S5, the waste materials to be collected include the completely cut A and B surfaces, and the debris generated when cutting the C surface.

[0062] In this optional embodiment, the steps of step S6 are specifically as follows:

[0063] The positioning push rod three 10 fixes the battery cell 2 after three-side cutting, and the core pushing plate 11 separates the core 13 from the shell under the push of the discharge push rod 12. The positioning push rod three 10 fixes the two sides of the battery cell 2, and the core pushing plate 11 pushes the core 13 out from the A side or the B side. The core 13 pushed out from the core pushing station is transported to the core storage box 16 for sealing treatment through the belt conveyor equipment 2 14, and the shell coming out of the core pushing processing station is transported to the shell pressing station 17 by the belt conveyor equipment 2 14. When it reaches the set position, the positioning push rods four 18 on both sides fix the shell. A shell pressing push rod 19 is provided above this position, which can flatten the shell to reduce the volume of the shell, and transport it to the shell storage box 20 through the conveyor belt.

[0064] In this optional embodiment, in step S7, during the separation process, the winding core 13 does not come into direct contact with the staff, and the process is carried out in a glove box.

[0065] In this optional embodiment, in the above-mentioned steps S3, S4 and S6, in the process where waste gas may be generated and electrolyte volatilization may occur, closed treatment and inert gas protection are required to avoid the risks of waste gas discharge and excessive electrolyte concentration leading to fire and explosion. That is, each workstation is equipped with nitrogen nozzles and detection equipment such as temperature sensors and oxygen sensors. When risks such as abnormal ignition temperature occur, the sensor transmits a signal to the central control room, and the nitrogen nozzle can be automatically opened to spray nitrogen to the abnormal temperature.

[0066] In order to facilitate understanding of the above technical solutions of the present invention, the above technical solutions of the present invention are further described below through a number of specific embodiments.

[0067] Embodiment 1

[0068] 10 used lithium batteries were discharged by high current discharge until the battery voltage was 500mV;

[0069] The lithium battery after discharge treatment is subjected to voltage test. Because the voltage of the lithium battery will rise after discharge, the battery after discharge is subjected to voltage test to further confirm that the battery voltage has reached the requirement. The unqualified battery will be treated as NG battery and handled separately.

[0070] Lithium batteries that pass the voltage test are punctured to collect the electrolyte and straighten the bulged and deformed batteries into a regular shape. This process requires airtight treatment and nitrogen protection.

[0071] The batteries that have been punctured enter the disassembly phase. First, the tab end, i.e., side A, is disassembled, followed by side B, and finally side C. All three sides are cut using pressure cutting. The disassembled waste will fall into the waste collection equipment. This process requires closed treatment and nitrogen protection.

[0072] After disassembly, the core is pushed, the shell is compressed and recovered, and the core is stored in the core temporary storage warehouse. This process requires closed treatment and nitrogen protection;

[0073] The temporarily stored core reels can be manually separated into positive and negative electrode sheets and separators. The core reels can be placed in a closed environment, such as a glove box, and the positive and negative electrode sheets and separators can be manually separated.

[0074] Embodiment 2

[0075] A method for dismantling waste lithium batteries of the present invention comprises the following steps:

[0076] 10 used lithium batteries were discharged by high current discharge until the battery voltage reached 500mV.

[0077] The lithium battery after discharge treatment is subjected to voltage test. Because the voltage of the lithium battery will rise after discharge, the battery after discharge is subjected to voltage test to further confirm that the battery voltage has reached the requirement. The unqualified battery will be treated as NG battery and handled separately.

[0078] Lithium batteries that pass the voltage test are punctured to collect the electrolyte and straighten the bulged and deformed batteries into a regular shape. This process requires airtight treatment and nitrogen protection.

[0079] The batteries that have been punctured enter the disassembly phase. First, the tab end, i.e., side A, is disassembled, followed by side B, and finally side C. All three sides are cut using saws. The disassembled waste will fall into the waste collection equipment. This process requires closed treatment and nitrogen protection.

[0080] After disassembly, the core is pushed, the shell is compressed and recovered, and the core is stored in the core temporary storage warehouse. This process requires closed treatment and nitrogen protection;

[0081] The temporarily stored core reels can be manually separated into positive and negative electrode sheets and separators. The core reels can be placed in a closed environment, such as a glove box, and the positive and negative electrode sheets and separators can be manually separated.

[0082] Embodiment 3

[0083] A method for dismantling waste lithium batteries of the present invention comprises the following steps:

[0084] 10 used lithium batteries were discharged by high current discharge until the battery voltage reached 1V.

[0085] The lithium battery after discharge treatment is subjected to voltage test. Because the voltage of the lithium battery will rise after discharge, the battery after discharge is subjected to voltage test to further confirm that the battery voltage has reached the requirement. The unqualified battery will be treated as NG battery and handled separately.

[0086] Lithium batteries that pass the voltage test are punctured to collect the electrolyte and straighten the bulged and deformed batteries into a regular shape. This process requires airtight treatment and nitrogen protection.

[0087] The batteries that have been punctured enter the disassembly phase. First, the tab end, i.e., side A, is disassembled, followed by side B, and finally side C. Sides A and B are cut by pressing, and side C is cut by sawing. The disassembled waste will fall into the waste collection equipment. This process requires closed treatment and nitrogen protection.

[0088] After disassembly, the core is pushed, the shell is compressed and recovered, and the core is stored in the core temporary storage warehouse. This process requires closed treatment and nitrogen protection;

[0089] The temporarily stored core reels can be manually separated into positive and negative electrode sheets and separators. The core reels can be placed in a closed environment, such as a glove box, and the positive and negative electrode sheets and separators can be manually separated.

[0090] Embodiment 4

[0091] A method for dismantling waste lithium batteries of the present invention comprises the following steps:

[0092] 10 used lithium batteries were discharged by high current discharge until the battery voltage reached 1V.

[0093] The lithium battery after discharge treatment is subjected to voltage test. Because the voltage of the lithium battery will rise after discharge, the battery after discharge is subjected to voltage test to further confirm that the battery voltage has reached the requirement. The unqualified battery will be treated as NG battery and handled separately.

[0094] Lithium batteries that pass the voltage test are punctured to collect the electrolyte and straighten the bulged and deformed batteries into a regular shape. This process requires airtight treatment and nitrogen protection.

[0095] The batteries that have been punctured enter the disassembly phase. First, the tab end, i.e., side A, is disassembled, followed by side B, and finally side C. All three sides are cut by grinding. The disassembled waste will fall into the waste collection equipment. This process requires closed treatment and nitrogen protection.

[0096] After disassembly, the core is pushed, the shell is compressed and recovered, and the core is stored in the core temporary storage warehouse. This process requires closed treatment and nitrogen protection;

[0097] The temporarily stored core reels can be manually separated into positive and negative electrode sheets and separators. The core reels can be placed in a closed environment, such as a glove box, and the positive and negative electrode sheets and separators can be manually separated.

[0098] As can be seen from the table below, the discharge method has little effect on the final product. Different discharge methods will affect the shape of the battery, but the present invention adds a puncture and shaping step, which greatly reduces the effect of different discharge methods on the shape of the battery. However, the battery may experience a voltage rebound after high current discharge, which can be avoided by adjusting the discharge voltage. From the cutting method point of view, three-sided pressing will cause the pressed surface of the core to deform, while sawing and grinding will produce a lot of waste chips. If the concentration of aluminum chips in the waste chips is high, there will be a risk of explosion. Therefore, use sawing or grinding as little as possible.

[0099] Overall, pressing cutting on the A and B sides and sawing on the C side are more efficient and safer, and the core integrity is higher.

[0100]

[0101] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for dismantling waste lithium batteries, characterized in that: include: Step S1, discharging the waste lithium battery; Step S2, performing a voltage test on the lithium battery after the discharge process; Step S3, puncturing the lithium battery that has passed the voltage test; Step S4, disassembling the punctured battery to form waste materials and battery cells (13); Step S5, recycling the waste generated during the disassembly process; Step S6, the disassembled lithium battery is subjected to core pushing treatment, the shell and other waste materials of the disassembled lithium battery are subjected to shell compression recovery treatment and temporarily stored in the shell temporary storage box (20), and the disassembled winding core (13) is temporarily stored in the winding core temporary storage bin (16); In step S7, the temporarily stored winding core (13) can be manually separated into positive and negative electrode sheets and separators.

2. A method for dismantling waste lithium batteries according to claim 1, characterized in that: The steps of step S1 are as follows: The discharge instrument is connected to the positive electrode tab (3) and the negative electrode tab (4) of the battery cell (2) to consume the remaining power of the battery cell (2) in the form of heat energy. The voltage during the discharge process is required to be less than 1V.

3. A method for dismantling waste lithium batteries according to claim 1, characterized in that: The steps of step S2 are as follows: A voltage detector (1) is used to perform voltage detection, a positioning push rod (5) device is used to fix the discharged battery cell (2) at a set position, and the residual voltage of the battery cell (2) is tested by connecting the copper plate (6) at the output end of the voltage detector (1) to the tab end of the battery cell (2).

4. A method for dismantling waste lithium batteries according to claim 1, characterized in that: The steps of step S3 are as follows: After the battery cell (2) is fixed to a set position below the puncturing knife (8) by the second positioning push rod (7), the puncturing knife (8) moves down to the top of the battery cell (2) and cuts the outer shell of the battery cell (2) according to the set depth to complete the puncturing action; after the puncturing action is completed, the battery cell (2) is pushed out of the puncturing station and transported forward to the shaping station by the first belt conveyor device (15), and the side shaping push rod (9) and the top shaping push rod (21) on the shaping station respectively squeeze the inside of the battery cell (2) from the side and the top at the same time to complete the shaping process.

5. A method for dismantling waste lithium batteries according to claim 1, characterized in that: The steps of step S4 are as follows: The tab end of the battery cell (2) is taken as the A side, the opposite side of the tab end is taken as the B side, and the left or right side of the battery cell (2) is taken as the C side. During the disassembly process, the A side is cut first, and then the B side is cut after the A side is cut, and finally the C side is cut.

6. A method for dismantling waste lithium batteries according to claim 5, characterized in that: The A surface, the B surface and the C surface may be cut by pressing, grinding or sawing.

7. A method for dismantling waste lithium batteries according to claim 5, characterized in that: In step S5, the waste materials to be collected include the completely cut A and B surfaces, and the debris generated when cutting the C surface.

8. A method for dismantling waste lithium batteries according to claim 1, characterized in that: The steps of step S6 are as follows: The positioning push rod three (10) fixes the battery core (2) after three-side cutting, and the core push plate (11) separates the core (13) from the shell under the push of the discharge push rod (12). The positioning push rod three (10) fixes the two side surfaces of the battery core (2), and the core push plate (11) pushes the core (13) out from the A side or the B side. The core (13) pushed out from the core pushing station is transported to the core temporary storage box (16) for sealing treatment through the belt conveyor device two (14). The shell coming out of the core pushing processing station is transported to the shell pressing station (17) by the belt conveyor device two (14). When it reaches the set position, the positioning push rods four (18) on both sides fix the shell. A shell pressing push rod (19) is provided above this position to flatten the shell to reduce the shell volume, and then transport it to the shell temporary storage box (20) through the conveyor belt.

9. A method for dismantling waste lithium batteries according to claim 1, characterized in that: In step S7, during the separation process, the winding core (13) does not come into direct contact with the staff, and the process is carried out in a glove box.

10. The method for dismantling waste lithium batteries according to claim 1, characterized in that: In the above-mentioned steps S3, S4 and S6, during the treatment process where waste gas may be generated and electrolyte volatilization may occur, closed treatment and inert gas protection are required, that is, each workstation is equipped with nitrogen nozzles and detection equipment such as temperature sensors and oxygen sensors. When risks such as abnormal ignition temperature occur, the sensor transmits a signal to the central control room, and the nitrogen nozzle can be automatically opened to spray nitrogen to the abnormal temperature.

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