Waste battery discharging and electrolyte recycling method and recycling equipment

Abstract

The invention provides a waste battery discharging and electrolyte recycling method. The waste battery discharging and electrolyte recycling method comprises the following steps: discharging a waste battery through a discharger; heating a positive current collector and a negative current collector of the waste battery through a heater; and the negative pressure recoverer is connected with the safety valve of the waste battery, so that the electrolyte of the waste battery is recovered. The waste battery discharge and electrolyte recovery equipment provided by the invention comprises a discharger, a heater and a negative pressure recoverer. According to the waste battery discharging and electrolyte recycling method and recycling equipment provided by the invention, the positive current collector and the negative current collector of the waste battery are heated by the heater, so that the heat of the heater can be directly conducted to the current collectors through the pole columns, and the electrolyte in the waste battery is heated more uniformly and quickly; and therefore, the production efficiency of electrolyte recovery and the recovery efficiency of the electrolyte are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of recycling of waste batteries, and in particular to a method and equipment for discharging waste batteries and recycling electrolytes. Background Art

[0002] Power batteries in new energy vehicles are currently the core products in the battery field. With the continuous development of the new energy vehicle industry, the recycling of power batteries is also an important issue that needs to be solved urgently. When the power battery reaches the end of its service life, it needs to be retired and enter the battery recycling market for recycling and reuse. Among them, for some power batteries that meet the usage conditions in some scenarios, they can be used at a lower level and applied to new fields; while for power batteries that no longer meet the usage standards, they need to be disassembled to extract the effective materials for recycling and reuse, so as to minimize the pollution caused by the scrapping of power batteries to the environment.

[0003] Currently, the recycling of waste power batteries in the industry is mainly divided into three methods: dry recycling, wet recycling, and physical recycling. For these three recycling methods, it is necessary to discharge the waste power batteries first, and then crush them to recover the high-valence metal elements in the waste power batteries. Currently, for the recycling of electrolytes in the industry, generally, the waste power batteries are soaked in salt water for discharging, and then the batteries are crushed and burned. The electrolytes in the waste batteries are recovered by collecting the volatilized gas after combustion and condensing the gas. There are the following problems with this method of recycling electrolytes: 1. When the waste power batteries enter the transportation and storage processes, due to the presence of electrolytes inside, they are prone to problems such as short circuits and thermal runaway; 2. When using salt water soaking for discharging, since the remaining power of each waste power battery is not fixed, in order to ensure that all discharges are completed, the power batteries need to be soaked for a long time, resulting in low efficiency and inconsistent discharge results in the discharging step. Moreover, the waste power batteries are prone to breakage and leakage during the soaking process, thus polluting the soaking solution.

[0004] In Chinese Patent Publication No. CN109346739B, a device and method for recycling lithium-ion battery electrolytes are provided. In its recycling device, the heating device is attached to the lithium-ion battery, and the heating device heats the lithium-ion battery through the outer shell of the lithium-ion battery. This heating method not only has low efficiency, but also the internal heat of the lithium-ion battery is uneven. For small-sized lithium-ion batteries, the attachment method can be used for heating, but for large-sized or lithium-ion batteries with a large electrolyte capacity, using this heating method either cannot achieve the full recovery of the electrolyte, and there will be residual electrolyte in the lithium-ion battery; or the heating is slow and the heating is uneven, resulting in low recycling efficiency.

[0005] In Chinese Patent Publication No. CN116053635B, a method for recycling lithium-ion battery electrolyte is provided. In this recycling method, a lithium battery is placed in a vacuum chamber with a set temperature, and the temperature of the vacuum chamber is adjusted to reach the set temperature. In this method, the cost of recycling the electrolyte of lithium batteries is extremely high. First, a vacuum chamber capable of accommodating lithium batteries in batches needs to be prepared, and then, the temperature inside the vacuum chamber also needs to be adjustable. The above two points have significantly increased the cost of electrolyte recycling and are not conducive to the popularization and promotion of this method.

[0006] Therefore, how to effectively recycle the electrolyte in waste power batteries and how to improve the recycling production efficiency of waste power batteries and the electrolyte recycling efficiency are all problems that urgently need to be solved in the battery recycling industry. Summary of the Invention

[0007] The purpose of the present invention is to solve the problems in the recycling process of existing waste power batteries, where the internal electrolyte is prone to short circuit and thermal runaway. When using the method of soaking in brine for discharging to recycle the electrolyte, the recycling time is long and the efficiency is low. When using a vacuum device for recycling, the equipment cost is high and it occupies a large space, resulting in high recycling costs and being not conducive to popularization. The present invention provides a method for discharging and recycling the electrolyte of waste batteries.

[0008] The technical solution adopted by the present invention to solve its technical problems is: A method for discharging and recycling the electrolyte of waste batteries includes: discharging the waste battery through a discharger; heating the positive current collector and the negative current collector of the waste battery through a heater, connecting the two ends of the heater to the positive electrode terminal and the negative electrode terminal of the waste battery respectively. The positive electrode terminal transfers the heat of the heater to the positive current collector of the waste battery, and the negative electrode terminal transfers the heat of the heater to the negative current collector of the waste battery, so that the electrolyte inside the waste battery is heated and vaporized; connecting a negative pressure recycler to the safety valve of the waste battery; recycling the electrolyte of the waste battery.

[0009] In one embodiment, the step of connecting a negative pressure recycler to the safety valve of the waste battery and recycling the electrolyte of the waste battery includes: covering the waste battery with a heat preservation sleeve outside; opening the safety valve of the waste battery and inserting the suction pipe of the negative pressure recycler into the safety valve; the vacuum pump of the negative pressure recycler provides suction pressure for the suction pipe; the suction pipe sucks the electrolyte of the waste battery to the condensation device.

[0010] In one embodiment, in the step of sucking the electrolyte of the waste battery to the condensation device by the suction pipe, it includes: first condensation, the electrolyte of the waste battery passes through the first condensation pipe of the condensation device for the first condensation, and the electrolyte is collected and drained into the recovery tank; the condensation temperature of the first condensation pipe of the condensation device is 5°C - 15°C.

[0011] In one embodiment, in the step of sucking the electrolyte of the waste battery to the condensation device by the suction pipe, it further includes: second condensation, after the electrolyte of the waste battery passes through the first condensation pipe of the condensation device, it then enters the second condensation pipe for the second condensation, and the electrolyte is collected and drained into the recovery tank; the condensation temperature of the second condensation pipe of the condensation device is -10°C - 0°C.

[0012] In one embodiment, it further includes adjusting the working state of the heater according to the working state of the negative pressure recovery device, including: detecting the temperature of the waste battery; determining the working state category of the negative pressure recovery device; adjusting the working state of the heater according to the working state category of the negative pressure recovery device.

[0013] In one embodiment, the working state category of the negative pressure recovery device is determined according to the temperature of the waste battery, and the working state category of the negative pressure recovery device includes: the first working state, the temperature of the waste battery is less than 100°C, and the negative pressure recovery device does not suck the electrolyte of the waste battery; the second working state, the temperature of the waste battery is between 100°C - 150°C, and the negative pressure recovery device sucks the electrolyte of the waste battery at the first pressure; the third working state, the temperature of the waste battery is greater than 150°C, and the negative pressure recovery device sucks the electrolyte of the waste battery at the second pressure.

[0014] In one embodiment, the first pressure is 35 - 45 kpa; the second pressure is 10 - 30 kpa.

[0015] In one embodiment, adjusting the working state of the heater according to the working state category of the negative pressure recovery device includes: the first heating state, when the working state of the negative pressure recovery device is in the first working state, the heater heats the waste battery at the first temperature; the second heating state, when the working state of the negative pressure recovery device is in the second working state, the heater heats the waste battery at the second temperature; the third heating state, when the working state of the negative pressure recovery device is in the third working state, the heater stops heating the waste battery.

[0016] In one embodiment, the first temperature is 100°C - 135°C; the second temperature is 130°C - 150°C.

[0017] In one embodiment, the step of discharging the waste battery by the discharger includes: connecting two ends of the discharger to the positive electrode terminal and the negative electrode terminal of the waste battery respectively, so as to form a discharge circuit between the discharger and the waste battery; detecting the voltage of the discharge circuit to obtain a discharge voltage; when the discharge voltage is less than 2V, disconnecting the discharger from the waste battery.

[0018] In one embodiment, in the step of discharging the waste battery by the discharger, the heater recovers the heat energy generated by the discharger.

[0019] The beneficial effects of a method for discharging a waste battery and recovering an electrolyte provided by the present invention are as follows: discharging the waste battery by a discharger, and heating the positive current collector and the negative current collector of the waste battery by a heater, with two ends of the heater being connected to the positive electrode terminal and the negative electrode terminal of the waste battery respectively, so that the heat of the heater can be directly conducted to the current collector through the electrode terminal, thereby making the heating of the waste battery faster and more uniform, making the electrolyte in the waste battery heated more uniformly and quickly, and further improving the production efficiency of recovering the electrolyte of the waste battery and the recovery efficiency of the electrolyte of the waste battery.

[0020] The present invention also provides a device for discharging a waste battery and recovering an electrolyte, which is applicable to the method for discharging a waste battery and recovering an electrolyte as described above, and includes: a heater disposed at a heating station, including a heat source, a first heating end and a second heating end that are connected to the heat source for heat conduction; when the waste battery is at the heating station, the first heating end is in heat conduction connection with the positive electrode terminal of the waste battery, and the second heating end is in heat conduction connection with the negative electrode terminal of the waste battery; and a negative pressure recovery device disposed at the heating station, including a suction pipe, a condensation device connected to the suction pipe, and a vacuum pump that provides a suction pressure for the suction pipe, when the waste battery is at the heating station, the suction pipe is inserted into the safety valve of the waste battery.

[0021] In one embodiment, the discharger includes a discharge resistor, a positive electrode access end and a negative electrode access end that are electrically connected to the discharge resistor. When the waste battery is at the discharge station, the positive electrode access end is electrically connected to the positive electrode terminal of the waste battery, and the negative electrode access end is electrically connected to the negative electrode terminal of the waste battery.

[0022] In one embodiment, the discharge resistor of the discharger is in contact with the heat source of the heater, and the heat source absorbs the heat generated by the discharge resistor.

[0023] In one embodiment, it further includes a station switching platform for supporting the waste battery and driving the waste battery to move at the discharging station and the heating station.

[0024] In one embodiment, the condensation device of the negative pressure recoverer includes a first condensing pipe connected to the suction pipe, a second condensing pipe connected to the first condensing pipe, and a recovery tank connected to the second condensing pipe.

[0025] In one embodiment, the heater further includes a heat preservation sleeve disposed at the heating station and sleeved outside the waste battery.

[0026] The beneficial effects of the waste battery discharging and electrolyte recovery device provided by the present invention are as follows: It includes a discharger for discharging the waste battery, and a heater. The first heating end of the heater is directly connected to the positive electrode terminal of the waste battery through heat conduction, so that the positive electrode terminal can directly transfer heat to the positive current collector. The second heating end of the heater is directly connected to the negative electrode terminal of the waste battery through heat conduction, so that the negative electrode terminal can directly transfer heat to the negative current collector. Thus, the current collector in the waste battery can be quickly heated, and it can also ensure that the inside of the waste battery is heated more uniformly, and the electrolyte vaporizes more quickly and uniformly. Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the description of the embodiments of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 It is a flowchart of a method for discharging a waste battery and recovering electrolyte provided by the first embodiment of the present invention; Figure 2 It is Figure 1 The sub-step flowchart of step S100 shown in Figure 3 It is Figure 1 The sub-step flowchart of step S120 shown in Figure 4 It is Figure 3 The sub-step flowchart of step S124 shown in Figure 5 It is Figure 1 The sub-step flowchart of step S130 shown in Figure 6 It is Figure 5 The sub-step flowchart of step S133 shown in Figure 7 It is a flowchart of sub-steps of step S124 in a method for discharging waste batteries and recovering electrolyte provided by the second embodiment of the present invention; Figure 8 It is a three-dimensional structural schematic diagram of a waste battery applicable to be recovered by a waste battery discharging and electrolyte recovery device provided by the present invention; Figure 9 It is a three-dimensional structural schematic diagram of a waste battery discharging and electrolyte recovery device provided by the present invention at the discharging station; Figure 10 It is a three-dimensional structural schematic diagram of a waste battery discharging and electrolyte recovery device provided by the present invention at the heating station; Figure 11 It is a front view of a waste battery discharging and electrolyte recovery device provided by the present invention.

[0029] Explanation of reference numerals: Waste battery discharging and electrolyte recovery device; Heater, 11 - First heating end, 12 - Second heating end, 13 - Heat source; Negative pressure recovery device, 21 - Suction pipe, 22 - Condensing device, 221 - First condensing pipe, 222 - Second condensing pipe, 223 - Recovery tank, 23 - Vacuum pump; Discharger, 31 - Positive electrode access terminal, 32 - Negative electrode access terminal, 33 - Discharge resistor; 40 - Station switching platform, 50 - Waste battery, 51 - Positive electrode terminal, 52 - Negative electrode terminal, 53 - Safety valve. Detailed implementation manners

[0030] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In the description of the present invention, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0032] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] The first embodiment See Figure 1-6 , which is a flowchart of a method for discharging waste batteries and recovering electrolytes provided by the first embodiment of the present invention.

[0034] See Figure 1 , the method for discharging waste batteries and recovering electrolytes provided by the first embodiment of the present invention includes the following steps: S100: Discharge the waste battery through a discharger. In this step S100, first perform a discharging operation on a single waste battery. After ensuring that the voltage of the waste battery is lower than the set value, then recover the electrolyte in the waste battery.

[0035] S110: Heat the positive current collector and the negative current collector of the waste battery through a heater. In step S110, connect the two ends of the heater to the positive terminal post and the negative terminal post of the waste battery respectively. The positive terminal post transfers the heat of the heater to the positive current collector of the waste battery, and the negative terminal post transfers the heat of the heater to the negative current collector of the waste battery, so that the electrolyte in the waste battery is heated and vaporized. In step S110, complete the heating of the interior of the waste battery that has already been discharged through the heater, so that the electrolyte located inside the battery is heated and vaporized, and then the recovery operation of the vaporized electrolyte is realized.

[0036] S120: Connect a negative pressure recovery device to the safety valve of the waste battery to recover the electrolyte of the waste battery. This step S120 and step S110 are synchronized in time, that is, while the heater heats the waste battery, the negative pressure recovery device recovers the electrolyte of the waste battery. In step S120, recover the electrolyte that has been heated and vaporized in the waste battery through the negative pressure recovery device, and directly open an opening at the safety valve of the waste battery, and complete the efficient recovery of the electrolyte through the connected negative pressure recovery device.

[0037] S130: Adjust the working state of the heater according to the working state of the negative pressure recovery device. This step S130 is carried out synchronously with step S110 and step S120, and in step S130, adjust the working state of the heater according to different working states of the negative pressure recovery device.

[0038] Please refer to Figure 2 , step S100 further includes the following steps: S101: Connect both ends of the discharger to the positive and negative electrode posts of the waste battery respectively, so as to form a discharge circuit between the discharger and the waste battery. In step S101, the positive terminal of the discharger needs to be fixedly connected to the positive electrode post of the waste battery, and the negative terminal of the discharger needs to be fixedly connected to the negative electrode post of the waste battery, so as to form a stable discharge circuit between the discharger and the waste battery, and the residual power inside the waste battery is exhausted through the discharger. The electrical connection between the discharger and the waste battery can be completed manually or by a robotic arm, and is not limited in this step. In this step S101, as the waste battery discharges continuously, the temperature of the discharger will rise. At this time, the heat energy generated by the discharger will be absorbed by the heater. That is, in step S101, the heater synchronously recovers the heat energy generated by the discharger due to the discharge operation of the waste battery.

[0039] S102: Detect the voltage of the discharge circuit to obtain the discharge voltage. In the discharge circuit connected between the discharger and the waste battery, the voltage of the discharge circuit is always detected by a voltmeter, and the discharge voltage on the discharge circuit can be obtained in real time. By monitoring the discharge voltage in this discharge circuit, it is judged whether step S100 is completed.

[0040] S103: When the discharge voltage is less than 2V, disconnect the discharger from the waste battery. When the discharge voltage on the discharge circuit detected by the voltmeter in the discharge circuit is lower than 2V, the discharger will give a prompt, and the positive terminal of the discharger will be separated from the positive electrode post of the waste battery. At the same time, the negative terminal of the discharger will be separated from the negative electrode post of the waste battery, so that the discharger is completely separated from the waste battery, and the discharge operation is completed.

[0041] Please refer to Figure 3 , step S120 further includes the following steps: S121: Wrap a heat-insulating sleeve outside the waste battery. In step S121, after the waste battery is heated, wrap a heat-insulating sleeve outside the waste battery, and then separate the electrode posts of the waste battery from the heater. This heat-insulating sleeve is used to keep the temperature of the waste battery within the temperature range we set, or to slow down the temperature reduction inside the waste battery as much as possible, so that the waste battery can still maintain a temperature suitable for electrolyte vaporization inside even without heating, which is convenient for the continuous output of the electrolyte.

[0042] S122: Open the safety valve of the waste battery and insert the suction pipe of the negative pressure recovery device into the safety valve. In step S122, the negative pressure recovery device is connected through the safety valve, which is an inherent component of the waste battery, and the connection with the negative pressure recovery device is achieved. The safety valve on the waste battery is first opened or destroyed to form a valve port connected to the inside of the waste battery, so that the suction pipe of the negative pressure recovery device can be completely connected to the valve port of the safety valve, and the suction pipe surrounds and seals the valve port of the waste battery.

[0043] S123: The vacuum pump of the negative pressure recovery device provides suction pressure for the suction pipe. After ensuring that step S122 is completed, the vacuum pump of the negative pressure recovery device starts to work, so that the negative pressure recovery device and the waste battery are both in a negative pressure state, thereby providing power for the discharge of the electrolyte in the waste battery.

[0044] S124: The suction pipe sucks the electrolyte of the waste battery to the condensation device. When the vacuum pump in the negative pressure recovery device starts to work, the waste battery is sealed and connected with the suction pipe of the negative pressure recovery device, thereby forming a negative pressure environment. The heated and vaporized electrolyte in the waste battery is discharged from the waste battery as the negative pressure continues to increase, and is guided to the condensation device for condensation operation along the guidance of the suction pipe, thereby realizing the recovery of the electrolyte in the waste battery.

[0045] See also Figure 4 , step S124 further includes the following steps: S1241: First condensation, the electrolyte of the waste battery is condensed for the first time through the first condenser tube of the condensation device, and the electrolyte is collected and merged into the recovery tank. In step S1241, after the electrolyte heated and vaporized in the waste battery is guided into the condensation device along the suction pipe of the negative pressure recovery device, it enters the first condenser tube in the condensation device for the first condensation recovery. In the first condenser tube, the high-temperature electrolyte undergoes the first condensation operation. The temperature in the first condenser tube is set between 5°C and 15°C, which can perform the first condensation recovery on the high-temperature vaporized electrolyte. The first condenser tube collects the condensed electrolyte and stores it in the recovery tank.

[0046] See also Figure 5 , step S130 further includes the following steps: S131: Detect the temperature of the used battery; in step S110, when the heater heats the used battery, step S130 starts synchronous work, and the temperature of the used battery is detected in real time by the thermometer, and the working state of the negative pressure recovery device is judged by the temperature. In step S131, the temperature detection of the used battery is divided into three different temperature sections, the first temperature section is less than 100°C, the second temperature section is between 100°C-150°C, and the third temperature section is greater than 150°C. The three different temperature sections are used to judge the different working states of the negative pressure recovery device.

[0047] S132: Determine the working state category of the negative pressure recovery device; determine the working state of the negative pressure recovery device based on the different temperatures of the waste batteries detected and collected in step S131. Due to the different temperatures of the waste batteries, the recovery of the electrolyte is in different recovery states. The working state of the negative pressure recovery device determines the efficiency and speed of the electrolyte recovery.

[0048] Among them, the working states of the negative pressure recovery device include the following categories: The first working state: the temperature of the waste battery is less than 100°C, and the negative pressure recovery device does not suck the electrolyte of the waste battery. When the negative pressure recovery device is in the first working state, the temperature of the waste battery is less than 100°C, and the degree of vaporization of its internal electrolyte is insufficient to meet the suction standard. At this time, the negative pressure recovery device does not start the recovery of the internal electrolyte of the waste battery to increase the rapid increase of the internal temperature of the waste battery. Moreover, when the temperature detects that the temperature of the waste battery is lower than 100°C due to the suction of the negative pressure recovery device, the negative pressure recovery device will also be turned off to increase the temperature inside the waste battery.

[0049] The second working state: the temperature of the waste battery is between 100°C and 150°C, and the negative pressure recovery device sucks the electrolyte of the waste battery at the first pressure. When the negative pressure recovery device is in the second working state, the temperature of the waste battery is higher than 150°C, and its internal electrolyte begins to gradually vaporize, and the recovery of the electrolyte can start. At this time, the negative pressure recovery device starts to suck and recover the internal electrolyte of the waste battery at the first pressure. At this time, the first pressure is between 35 - 45 kPa, and this first pressure is adjusted according to the different temperatures of the waste battery. The higher the temperature, the lower the pressure. That is, when the detected temperature of the waste battery is 100°C, the first pressure is 45 kPa, and when the detected temperature of the waste battery is 150°C, the first pressure is 35 kPa. This first pressure provides sufficient pressure inside the waste battery so that the vaporized electrolyte inside can be quickly discharged.

[0050] The third working state: the temperature of the waste battery is greater than 150°C, and the negative pressure recovery device sucks the electrolyte of the waste battery at the second pressure. When the negative pressure recovery device is in the third working state, the temperature of the waste battery is higher than 150°C, and its internal temperature is too high. At this time, the negative pressure recovery device sucks the electrolyte of the waste battery at the second pressure. The second pressure is between 10 - 30 kPa, and as the detected temperature of the waste battery is higher, this second pressure gradually decreases.

[0051] S133: Adjust the operating state of the heater according to the operating state category of the negative pressure recovery device. In step S132, the operating state category of the negative pressure recovery device is judged based on the detected temperature of the waste battery. In step S133, the operating state of the heater is adjusted according to the operating state category of the negative pressure recovery device to ensure a safe, stable and efficient process during the electrolyte recovery of the waste battery.

[0052] Please refer to Figure 6 , step S133 further includes the following steps: S1331: First heating state. When the operating state of the negative pressure recovery device is in the first operating state, the heater heats the waste battery at the first temperature. In step S1331, when the operating state of the negative pressure recovery device is in the first operating state, the detected temperature of the waste battery is lower than 100 °C. At this time, the negative pressure recovery device does not aspirate the electrolyte, and the temperature of the waste battery cannot reach the aspirable temperature. Therefore, the heater quickly heats the waste battery at the first temperature. The first temperature is generally controlled between 100 °C and 135 °C, and the first temperature is determined by the operating temperature of the recovery environment. Generally, the lower the operating temperature, the higher the first temperature, so that the waste battery can quickly heat up to the electrolyte aspiration standard.

[0053] S1332: Second heating state. When the operating state of the negative pressure recovery device is in the second operating state, the heater heats the waste battery at the second temperature. In step S1332, when the operating state of the negative pressure recovery device is in the second operating state, the detected temperature of the waste battery is between 100 °C and 150 °C. At this time, the negative pressure recovery device aspirates the electrolyte, and the temperature of the waste battery will decrease as the electrolyte is aspirated. In order to ensure that the temperature of the waste battery can always be between 100 °C and 150 °C, the heating temperature of the heater needs to increase compared to the first heating state. At this time, the heater heats at the second temperature. The second temperature is generally controlled between 130 °C and 150 °C. The second temperature is higher than the first temperature and generally increases by 10 °C - 50 °C based on the first temperature to compensate for the heat taken away by the rapid aspiration of the negative pressure recovery device, so that the temperature of the waste battery can always be between 100 °C and 150 °C during the electrolyte aspiration process.

[0054] S1333: Third heating state. When the operating state of the negative pressure recovery device is in the third operating state, the heater stops heating the waste battery. In step S1333, when the operating state of the negative pressure recovery device is in the third operating state, the temperature of the waste battery is greater than 150 °C. At this time, to ensure the safe recovery of the electrolyte of the waste battery, the heater stops heating the waste battery, and with the continuous suction pressure of the negative pressure recovery device, quickly takes away the temperature inside the waste battery, so that the waste battery will not get out of control.

[0055] The present invention provides a method for discharging and recovering electrolyte of waste batteries. A heater is used to heat the positive current collector and the negative current collector of the waste batteries. The two ends of the heater are respectively connected to the positive electrode pole and the negative electrode pole of the waste batteries, so that the heat of the heater can be directly transferred to the current collector through the poles. The heating of the waste batteries is faster and more uniform, and the electrolyte in the waste batteries is heated more uniformly and faster, thereby improving the production efficiency of the electrolyte recovery of the waste batteries and improving the electrolyte recovery efficiency of the waste batteries.

[0056] Second embodiment See also Figure 7 , is a sub-flow chart of step S124 in a method for discharging a waste battery and recovering an electrolyte provided in the second embodiment of the present invention. The difference between the second embodiment of the present invention and the first embodiment is that the method for discharging a waste battery and recovering an electrolyte provided in this embodiment, in step S124, further includes the following steps: S1242: Second condensation, the electrolyte of the waste battery passes through the first condensation tube of the condensation device, and then enters the second condensation tube for the second condensation, and the electrolyte is collected and merged into the recovery tank. In step S1242, the vaporized electrolyte that has not been condensed after passing through the first condensation tube will enter the second condensation tube with the action of the vacuum pump of the negative pressure recovery device, and the second condensation recovery will be carried out in the second condensation tube. In the second condensation tube, the vaporized electrolyte after cooling is subjected to the second condensation operation. The temperature in the second condensation tube is set between -10℃-0℃, and the electrolyte after cooling can be subjected to the second condensation recovery. The second condensation tube collects the condensed electrolyte into the recovery tank for storage. After passing through the first condensation tube and the second condensation tube, most of the vaporized electrolyte discharged from the waste battery will be condensed and recovered.

[0057] In this embodiment, a second condenser is arranged after the first condenser, that is, when the vaporized electrolyte is condensed, a second condensation operation is added, and the condensation temperature of the second condensation operation is lower than the condensation temperature of the first condensation operation, so that the recovery efficiency of the electrolyte is higher, and the difference between the amount of recovered electrolyte and the amount of weight loss of the waste battery is smaller, that is, less liquid evaporates.

[0058] Third embodiment See also Figure 8-11 , is a waste battery discharge and electrolyte recovery device 100 provided in the third embodiment of the present invention. The waste battery discharge and electrolyte recovery device 100 provided in the present invention is applicable to the waste battery discharge and electrolyte recovery method mentioned above.

[0059] like Figure 8As shown, it is a schematic three-dimensional structure diagram of a waste battery 50 applicable to the waste battery discharging and electrolyte recovery device 100 provided by the present invention. The waste battery 50 has a casing, and a positive electrode terminal 51 and a negative electrode terminal 52 are provided at one end of the casing. A safety valve 53 is provided between the positive electrode terminal 51 and the negative electrode terminal 52. In the waste battery discharging and electrolyte recovery device 100 provided by the present invention, the heater 10 is directly connected to the positive electrode terminal 51 and the negative electrode terminal 52 of the waste battery 50 to conduct heat, so that the heat can directly reach the current collector inside the casing of the waste battery 50, and the purpose of heating the electrolyte inside the waste battery 50 is achieved by the heat generation of the current collector, thereby making the electrolyte of the waste battery 50 more evenly heated and heated more quickly.

[0060] As Figure 9 and Figure 10 shown, it is a schematic three-dimensional structure diagram of the waste battery discharging and electrolyte recovery device 100 provided by the present invention when it is in the discharging station or the heating station.

[0061] The waste battery discharging and electrolyte recovery device 100 provided by the present invention includes a discharger 30 arranged at the discharging station, a heater 10 and a negative pressure recovery device 20 arranged at the heating station. Among them, the discharger 30 is used to perform a discharging operation on the waste battery 50 that needs electrolyte recovery, ensuring that the waste battery 50 is in a fully discharged state when it is in the heating station to ensure the safety of electrolyte recovery. The discharger 30 is used before the waste battery 50 is heated and can discharge the electric quantity in the waste battery 50 to a safe value. The heater 10 includes a heat source 13, a first heating end 11 and a second heating end 12 that are connected to the heat source 13 for heat conduction; when the waste battery 50 is in the heating station, the first heating end 11 is in heat conduction connection with the positive electrode terminal 51 of the waste battery 50, and the second heating end 12 is in heat conduction connection with the negative electrode terminal 52 of the waste battery 50. The heat source 13 of the heater 10 can directly transfer heat to the positive electrode terminal 51 and the negative electrode terminal 52 of the waste battery 50 through the first heating end 11 and the second heating end 12, and transfer it to the positive current collector inside the waste battery 50 through the positive electrode terminal 51 and to the negative current collector inside the waste battery 50 through the negative electrode terminal 52. This heating method of directly conducting heat to the current collector through the electrode terminal has higher heating efficiency and shorter time to reach the preset temperature. In this embodiment, the heat source 13 of the heater 10 is a heat-conducting oil pipe.

[0062] Moreover, the heater 10 provided by the present invention further includes a heat preservation sleeve (not shown in the figure) disposed on the heating station and sleeved outside the waste battery 50. When the waste battery 50 is disposed on the heating station, the heat preservation sleeve can be wrapped outside the waste battery 50. On the one hand, the heat preservation sleeve is used to keep the waste battery 50 warm to quickly increase the temperature inside the waste battery 50; on the other hand, the heat preservation sleeve is used to wrap the waste battery 50 to isolate the waste battery 50 from the outside during the heating stage and the electrolyte suction process, improve the safety factor and reduce potential safety hazards.

[0063] Using the method of the first embodiment of the present invention, the equipment 100 of this embodiment is used to recover the electrolyte from the bare battery. After discharging the bare battery first, then heating it, the bare battery is heated to 130 °C, which takes 1 hour and 31 minutes. After heating, the electrolyte of the bare battery is suctioned. The entire electrolyte suction process takes 3 hours and 54 minutes. The weight loss of the bare battery after completing the electrolyte suction and the weight of the electrolyte solvent after suction differ by 24 grams. During this electrolyte recovery process, no heat preservation sleeve was installed on the bare battery during either the heating process or the electrolyte recovery process.

[0064] Using the method of the first embodiment of the present invention, the equipment 100 of this embodiment is used to recover the electrolyte from the bare battery. After discharging the bare battery first, then heating it, and a heat preservation sleeve is installed during the heating process and the suction process. The bare battery is heated to 121 °C, which takes 1 hour and 15 minutes. The entire electrolyte suction process takes 3 hours and 20 minutes. The weight loss of the bare battery after completing the electrolyte suction and the weight of the electrolyte solvent after suction differ by 32 grams.

[0065] Using the method of the first embodiment of the present invention, the equipment 100 of this embodiment is used to recover the electrolyte from the bare battery. After discharging the bare battery first, then heating it, and a heat preservation sleeve is installed during the heating process and the suction process. The bare battery is heated to 128 °C, which takes 1 hour and 22 minutes. The entire electrolyte suction process takes 2 hours and 45 minutes. The weight loss of the bare battery after completing the electrolyte suction and the weight of the electrolyte solvent after suction differ by 38 grams.

[0066] During the above three processes of recovering the electrolyte from the bare battery, it can be clearly seen that during the heating and suction processes of the waste battery, adding a heat preservation sleeve can effectively shorten the heating and suction time of the battery, thereby improving the efficiency of recovering the electrolyte from the waste battery. At the same time, the higher the heating and suction temperature of the waste battery, the lower the recovery rate. Because after the electrolyte is heated to a high temperature and recovered using the method of the first embodiment, the vaporized electrolyte is not sufficiently condensed, resulting in a large difference in the number of grams between the weight loss of the bare battery after suction and the weight of the electrolyte solvent after suction. Therefore, after completing the first condensation, performing a second condensation operation will significantly reduce the difference in the number of grams between the weight loss of the bare battery after suction and the weight of the electrolyte solvent after suction, so as to improve the electrolyte recovery rate.

[0067] As Figure 9 shown, the negative pressure recovery device 20 located at the heating station includes a suction pipe 21, a condensation device 22 connected to the suction pipe 21, and a vacuum pump 23 that provides suction pressure for the suction pipe 21. The vacuum pump 23 provides power for the entire negative pressure recovery device 20, facilitating the rapid discharge of the electrolyte from the used battery 50. The condensation device 22 is used to condense the vaporized electrolyte drawn out of the used battery 50, thereby condensing the vaporized electrolyte again to form a liquid solvent and collecting the liquid solvent. When the used battery 50 is at the heating station, the suction pipe 21 is inserted into the safety valve 53 of the used battery 50, and a negative pressure suction force is provided for the suction pipe 21 through the vacuum pump 23, so that the vaporized electrolyte in the used battery 50 can enter the suction pipe 21 along with the safety valve 53 and enter the condensation device 22.

[0068] Specifically, in the discharge and electrolyte recovery device 100 for used batteries provided by the present invention, the condensation device 22 of the negative pressure recovery device 20 includes a first condensation pipe 221 connected to the suction pipe 21, a second condensation pipe 222 connected to the first condensation pipe 221, and a recovery tank 223 connected to the second condensation pipe 222. The first condensation pipe 221 performs the first condensation operation on the vaporized electrolyte, and the second condensation pipe 222 performs the second condensation operation on the vaporized electrolyte. The electrolyte solvent condensed after the two condensation operations enters the recovery tank 223.

[0069] As Figure 9 shown, it is a schematic three-dimensional structure diagram of the discharge and electrolyte recovery device 100 for used batteries when it is at the discharge station. The discharger 30 is used to perform a discharging operation on the used battery 50 that requires electrolyte recovery, ensuring that the used battery 50 is in a fully discharged state when it is at the heating station to ensure the safety of electrolyte recovery. The discharger 30 can be used before the used battery 50 is heated to discharge the power in the used battery 50 to a safe value.

[0070] As Figure 11 shown, the discharger 30 includes a discharge resistor 33, a positive electrode access terminal 31 and a negative electrode access terminal 32 that are electrically connected to the discharge resistor 33. When the used battery 50 is at the discharge station, the positive electrode access terminal 31 is electrically connected to the positive electrode terminal 51 of the used battery 50, and the negative electrode access terminal 32 is electrically connected to the negative electrode terminal 52 of the used battery 50. As Figure 10 shown, the positive electrode access terminal 31 and the negative electrode access terminal 32 of the discharger 30 are respectively electrically connected to the positive electrode terminal 51 and the negative electrode terminal 52 of the used battery 50 to form a discharge circuit. During the discharging process, the discharge resistor 33 continuously generates heat.

[0071] Furthermore, as Figure 9 orFigure 10 As shown, the discharge resistor 33 of the discharger 30 is in contact with the heat source 13 of the heater 10. When the waste battery 50 is at the discharge station, the discharge resistor 33 generates heat during the discharge process of the waste battery 50, and the heat source 13 of the heater 10 absorbs the heat generated by the discharge resistor 33.

[0072] Furthermore, as Figure 9 or Figure 10 shown, the discharging and electrolyte recovery device 100 for waste batteries provided by the present invention further includes a station switching platform 40 that supports the waste battery 50 and drives the waste battery 50 to move between the discharge station and the heating station. The station switching platform 40 is used for switching the station of the waste battery 50 to facilitate the rapid and efficient recovery of the electrolyte of the waste battery 50.

[0073] The first heating end 11 of the heater 10 of the discharging and electrolyte recovery device 100 for waste batteries provided by the present invention is directly connected to the positive electrode post 51 of the waste battery 50 by heat conduction, so that the positive electrode post 51 can directly transfer heat to the positive current collector. The second heating end 12 of the heater 10 is directly connected to the negative electrode post 52 of the waste battery 50 by heat conduction, so that the negative electrode post 52 can directly transfer heat to the negative current collector, thereby quickly heating the current collector in the waste battery 50, and ensuring more uniform heating inside the waste battery 50, and more rapid and uniform vaporization of the electrolyte.

[0074] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for discharging waste batteries and recovering electrolyte, characterized in that, Including: Discharging the waste battery through a discharger; Heating the positive current collector and the negative current collector of the waste battery through a heater, connecting both ends of the heater to the positive terminal post and the negative terminal post of the waste battery respectively, the positive terminal post transferring the heat of the heater to the positive current collector of the waste battery, and the negative terminal post transferring the heat of the heater to the negative current collector of the waste battery, so that the electrolyte in the waste battery is heated and vaporized; Connecting a negative pressure recycler to the safety valve of the waste battery to recover the electrolyte of the waste battery.

2. The method for discharging waste batteries and recovering electrolytes according to claim 1, characterized in that, The connecting a negative pressure recycler to the safety valve of the waste battery to recover the electrolyte of the waste battery includes: Wrapping a heat preservation sleeve outside the waste battery; Opening the safety valve of the waste battery and inserting the suction pipe of the negative pressure recycler into the safety valve; The vacuum pump of the negative pressure recycler provides suction pressure for the suction pipe; The suction pipe sucks the electrolyte of the waste battery to the condensation device.

3. The method for discharging and electrolyte recovery of a waste battery according to claim 2, wherein In the step of the suction pipe sucking the electrolyte of the waste battery to the condensation device, it includes: The first condensation, the electrolyte of the waste battery undergoes the first condensation through the first condenser tube of the condensation device, and the electrolyte is collected and drained into the recovery tank; the condensation temperature of the first condenser tube of the condensation device is 5°C - 15°C.

4. The method for discharging waste batteries and recovering electrolytes according to claim 3, characterized in that, In the step of the suction pipe sucking the electrolyte of the waste battery to the condensation device, it further includes: The second condensation, after the electrolyte of the waste battery passes through the first condenser tube of the condensation device, it then enters the second condenser tube for the second condensation, and the electrolyte is collected and drained into the recovery tank; the condensation temperature of the second condenser tube of the condensation device is -10°C - 0°C.

5. The method for discharging waste batteries and recovering electrolytes according to claim 1, characterized in that, It further includes adjusting the working state of the heater according to the working state of the negative pressure recycler, including: Detecting the temperature of the waste battery; Determining the working state category of the negative pressure recycler; Adjusting the working state of the heater according to the working state category of the negative pressure recycler.

6. The method for discharging and electrolyte recovery of a waste battery according to claim 5, wherein The working state category of the negative pressure recycler is determined according to the temperature of the waste battery, and the working state category of the negative pressure recycler includes: The first working state, the temperature of the waste battery is less than 100°C, and the negative pressure recycler does not suck the electrolyte of the waste battery; The second working state, the temperature of the waste battery is between 100°C - 150°C, and the negative pressure recycler sucks the electrolyte of the waste battery with the first pressure; The third working state, the temperature of the waste battery is greater than 150°C, and the negative pressure recycler sucks the electrolyte of the waste battery with the second pressure.

7. The method for discharging waste batteries and recovering electrolytes according to claim 6, wherein The first pressure is 35 - 45 kPa; the second pressure is 10 - 30 kPa.

8. The method for discharging waste batteries and recovering electrolyte according to claim 6, characterized in that, The adjusting the working state of the heater according to the working state category of the negative pressure recycler includes: The first heating state, when the working state of the negative pressure recycler is in the first working state, the heater heats the waste battery at the first temperature; The second heating state, when the working state of the negative pressure recycler is in the second working state, the heater heats the waste battery at the second temperature; The third heating state, when the working state of the negative pressure recycler is in the third working state, the heater stops heating the waste battery.

9. The method for discharging waste batteries and recovering electrolyte according to claim 8, characterized in that, The first temperature is 100°C - 135°C; the second temperature is 130°C - 150°C.

10. A method for discharging waste batteries and recovering electrolytes according to claim 1, characterized in that, The step of discharging the waste battery through the discharger includes: Connecting the two ends of the discharger to the positive electrode terminal and the negative electrode terminal of the waste battery respectively, so that a discharge circuit is formed between the discharger and the waste battery; Detecting the voltage of the discharge circuit to obtain the discharge voltage; When the discharge voltage is less than 2V, disconnect the discharger from the waste battery.

11. A method for discharging waste batteries and recovering electrolytes according to claim 10, characterized in that, In the step of discharging the waste battery through the discharger, the heater recovers the heat energy generated by the discharger.

12. A discharging and electrolyte recovery device for waste batteries, applicable to the method for discharging and electrolyte recovery of waste batteries according to any one of claims 1-11, characterized in that, Including: A discharger, arranged at the discharge station, to discharge the waste battery; A heater, arranged at the heating station, including a heat source, a first heating end and a second heating end that are thermally conductive with the heat source; when the waste battery is at the heating station, the first heating end is thermally conductive connected to the positive electrode terminal of the waste battery, and the second heating end is thermally conductive connected to the negative electrode terminal of the waste battery; And a negative pressure recycler, arranged at the heating station, including a suction pipe, a condensation device connected to the suction pipe, and a vacuum pump that provides suction pressure for the suction pipe. When the waste battery is at the heating station, the suction pipe is inserted into the safety valve of the waste battery.

13. The discharge and electrolyte recovery equipment for waste batteries according to claim 12, characterized in that The discharger includes a discharge resistor, a positive electrode access end and a negative electrode access end that are electrically connected to the discharge resistor. When the waste battery is at the discharge station, the positive electrode access end is electrically connected to the positive electrode terminal of the waste battery, and the negative electrode access end is electrically connected to the negative electrode terminal of the waste battery.

14. A discharge and electrolyte recovery device for waste batteries according to claim 13, characterized in that, The discharge resistor of the discharger is in contact with the heat source of the heater, and the heat source absorbs the heat generated by the discharge resistor.

15. A discharging and electrolyte recovery device for waste batteries according to claim 13, characterized in that, It also includes a station switching platform that supports the waste battery and drives the waste battery to move between the discharge station and the heating station.

16. The discharging and electrolyte recovery device for waste batteries according to claim 12, characterized in that, The condensation device of the negative pressure recycler includes a first condensation pipe connected to the suction pipe, a second condensation pipe connected to the first condensation pipe, and a recovery tank connected to the second condensation pipe.

17. A discharge and electrolyte recovery device for waste batteries according to claim 12, characterized in that, The heater also includes a heat preservation sleeve arranged at the heating station and sleeved outside the waste battery.

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