Pulse type pretreatment method for waste lithium battery pole shank

Abstract

The invention specifically discloses a pulse-type pretreatment method for a waste lithium battery pole shank, which comprises the following steps: at a set pretreatment temperature Temp, performing pulse-type pyrolysis defluorination replacement treatment on the waste lithium battery pole shank, with the total pretreatment time being t minutes, the time of one pulse period being T minutes, and the number of pulse periods being Tnum; wherein one pulse period comprises two steps, the first step is a cracking hydrogen-containing gas defluorination reaction process, and the second step is an inert carrier gas replacement process. According to the application, the defluorination reaction is effectively promoted through the defluorination reaction and carrier gas replacement of the pyrolyzable hydrogen-containing gas of a plurality of pulse periods, so that the rapid reaction generation and rapid removal of gas-phase fluoride are achieved, and in addition, the thermal decomposition of a binder in an electrode active material is enhanced by utilizing a periodic pulse mode, so that the performance of the electrode is improved. And meanwhile, the binding force between the electrode active material and the foil is reduced, and the stripping effect of the electrode active material is improved.

Description

Technical Field

[0001] The present application belongs to the technical field of lithium battery recycling, and in particular relates to a pulse pretreatment method for waste lithium battery cores. Background Art

[0002] Waste lithium-ion batteries contain toxic and harmful substances such as fluorine, organic solvents, and heavy metals, and must be recycled and processed in a standardized manner; at the same time, waste lithium-ion batteries are also valuable "urban mines" that contain metal elements such as lithium, copper, and aluminum, which are of great significance to the realization of closed-loop development of the lithium-ion battery industry chain.

[0003] In the process of recycling and reusing waste lithium batteries, one of the key processes at the front end is the pretreatment of the waste lithium battery core, the purpose of which is to separate the electrode active material from the copper foil and aluminum foil to obtain battery black powder with lower copper and aluminum content.

[0004] At present, the pretreatment method of waste lithium battery cores is generally to achieve the following effects by means of coarse crushing, pyrolysis, fine crushing, and sorting (a combination of screening, air separation, magnetic separation, gravity separation, flotation, etc.): First, the binding force between the electrode active substance and the foil is reduced so that the electrode active substance can be peeled off from the surface of the foil; second, during the pyrolysis process, that is, under certain temperature conditions, the organic solvent, fluorine-free binder, fluorine-containing electrolyte, fluorine-containing binder or additive contained in the lithium battery black powder is promoted to be completely or partially decomposed, and part of the decomposition product is gaseous, and part of the harmful fluorine-containing substances originally contained in the lithium battery black powder are removed through the gas phase; third, during the sorting process, the active substance is separated from the metal copper foil and metal aluminum as much as possible to obtain battery black powder with low copper and aluminum content.

[0005] However, the current methods for pre-processing waste lithium battery cores have the following problems and shortcomings:

[0006] First, the electrode active material and the foil are still tightly bonded, making it difficult to peel off. In the current pretreatment method, the pyrolysis process destroys the viscosity of the binder, thereby reducing the bonding strength between the active material layer and the foil surface; because the electrode preparation process undergoes a rolling operation, the foil surface is roughened during the rolling process, and the electrode active material and the rough surface form a certain bite effect, which prevents the electrode active material from being peeled off from the foil. The pretreatment process can destroy this bite effect to a certain extent. However, on the whole, the current pretreatment method still cannot achieve a good effect of mutual peeling of the electrode active material and the foil.

[0007] Second, the fluorine content in the battery black powder obtained after the pretreatment of the waste lithium battery core is still relatively high. During the pretreatment of the waste lithium battery core, the pyrolysis process is the key step for fluorine removal. Fluorine-containing substances decompose under the action of temperature to generate hydrogen fluoride, which enters the gas phase and is removed. However, the actual pyrolysis defluorination process has a synergistic effect. During the removal process, the generated hydrogen fluoride will also react chemically with the metal elements in the electrode active material to generate more stable metal fluorides due to its high activity. The metal fluorides remain in the battery black powder in the solid phase, resulting in a high fluorine content in the battery black powder.

[0008] Third, the battery black powder obtained after pretreatment of the waste lithium battery core has high copper and aluminum content. With the current pretreatment method, the copper and aluminum content in the battery black powder is generally above 0.5%, which requires copper and aluminum to be removed in the subsequent battery black powder recycling process, reducing economic efficiency.

[0009] Fourth, it brings the problem of impurity removal to the subsequent recycling of battery black powder, which increases the cost. The high fluorine content in battery black powder seriously affects the recovery of valuable elements in the subsequent process, and fluorine enters the gas, liquid and solid phases in the subsequent process, which brings processing difficulties and increases the cost of processing; the high copper and aluminum content in battery black powder reduces the recovery of copper and aluminum metals on the one hand, resulting in value loss. In addition, the subsequent recycling process of battery black powder also requires the removal of copper and aluminum impurities, which increases the cost.

[0010] Therefore, there is an urgent need to develop a waste lithium battery core pretreatment technology that can promote good peeling of electrode active materials and foil, has low fluorine content in battery black powder, and is low-cost, so as to maximize the recycling value of waste lithium batteries. Summary of the invention

[0011] This application is made in view of the above technical problems and aims to provide a pulse pretreatment method for waste lithium battery cores with high defluorination rate, high efficiency and low cost.

[0012] In order to solve the above technical problems, the present application provides a pulse pretreatment method for waste lithium battery cores, the method comprising:

[0013] At the set pretreatment temperature Temp, the waste lithium battery core is subjected to pulsed thermal defluorination and replacement treatment, the total pretreatment time is t minutes, one pulse cycle time is T minutes, the number of pulse cycles is T_num, the pulse cycle time T satisfies: 5 minutes ≤ T ≤ 60 minutes, and the number of pulse cycles T_num satisfies: 2 ≤ T_num ≤ 20;

[0014] Among them, a pulse cycle includes two steps. The first step is the defluorination reaction process of the crackable hydrogen-containing gas. The defluorination reaction time of the crackable hydrogen-containing gas is t1 minutes, and the flow rate of the crackable hydrogen-containing gas is V1 cubic meters / minute. The second step is the inert carrier gas replacement process. The inert carrier gas replacement time is t2 minutes, and the inert carrier gas flow rate is V2 cubic meters / minute. t1 and t2 satisfy: 0.1≤t1 / t2≤10, V1 and V2 satisfy: 1≤(V1*t1) / (V2*t2)≤10.

[0015] In some embodiments, the total pretreatment time t satisfies: 30 minutes ≤ t ≤ 180 minutes, and the pretreatment temperature Temp satisfies: 500°C ≤ Temp ≤ 650°C.

[0016] In some embodiments, the crackable hydrogen-containing gas refers to a mixture of one or more of hydrogen, hydrocarbon organic gas, water vapor, alcohol organic gas, acid organic gas, ester organic gas, and carbonate organic gas; the inert gas refers to a mixture of one or more of nitrogen, helium, and argon.

[0017] Compared with the prior art, the pulse pretreatment method for waste lithium battery cores provided in this application has the following beneficial technical effects:

[0018] (1) The present application uses multiple periodic pulse methods for pretreatment, which can effectively reduce the bonding force between the electrode active material and the foil material, improve the stripping effect of the electrode active material, and make the electrode active material easy to separate from the surface of the lithium battery black powder core material. The copper and aluminum contents in the lithium battery black powder obtained after pretreatment are both less than 0.1%, achieving efficient separation of copper and aluminum in the waste lithium battery core material. That is, in the present application, the pulse method can enhance the thermal decomposition of the binder in the electrode active material. At the same time, the decomposable hydrogen-containing gas can undergo catalytic decomposition at a preset temperature to generate hydrogen atoms to form a reducing atmosphere. The surface of the waste lithium battery core material is affected by the reducing atmosphere, and the bonding force between the electrode active material and the foil surface is greatly weakened;

[0019] (2) The present application effectively promotes the efficient and deep removal of fluorine from lithium battery black powder by performing defluorination treatment and carrier gas replacement treatment of crackable hydrogen-containing gas in each pulse cycle, so that the fluorine content in the pretreated lithium battery black powder is less than 0.05%. In the process of removing fluorine from battery black powder by traditional pyrolysis method, due to the existence of secondary synergistic effect, a competitive reaction of "fixing fluorine" occurs simultaneously during the defluorination process, that is, the hydrogen fluoride gas generated in the defluorination process will also react chemically with the metal elements in the lithium battery black powder to generate solid metal fluorides. The fluorine element that should have been removed is fixed in the lithium battery black powder, making it difficult to remove fluorine from the lithium battery black powder more cleanly and thoroughly; in the present application, through multiple cycles of defluorination reaction process of crackable hydrogen-containing gas and inert carrier gas replacement treatment, the defluorination reaction can be effectively promoted and the fixing fluorine reaction can be inhibited, thereby achieving the implementation effect of rapid reaction generation and rapid removal of gas-phase fluorides, and realizing efficient and deep removal of fluorine from lithium battery black powder;

[0020] (3) This application can help reduce the recycling cost of waste lithium battery cores. In this application, by concentrating and deeply removing fluorine at the front end, the control and management costs of fluorine in the subsequent process can be greatly reduced, and it is also conducive to the efficient recovery of other valuable elements; at the same time, this application achieves a high yield of copper and aluminum through efficient separation of copper and aluminum, that is, reducing the content of copper and aluminum in lithium battery black powder, on the one hand reducing the cost of impurity removal, and on the other hand the direct recovery value of metallic copper and metallic aluminum is higher.

[0021] In summary, the pulse pretreatment method for waste lithium battery cores provided in the present application has the characteristics of high defluorination rate, high efficiency and low cost, and has significant cost advantages compared with existing traditional process methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a process flow chart of the pulse pretreatment method of waste lithium battery cores in this application. DETAILED DESCRIPTION

[0024] "Scope" disclosed in the present application is limited in the form of lower limit and upper limit, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range. The scope limited in this way can be including end values ​​or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a specific parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following scope can be all expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the present application, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0025] refer to Figure 1 As shown, the embodiment of the present application provides a pulse pretreatment method for waste lithium battery cores, the method comprising:

[0026] At the set pretreatment temperature Temp, the waste lithium battery core is subjected to pulsed thermal defluorination and replacement treatment, the total pretreatment time is t minutes, one pulse cycle time is T minutes, the number of pulse cycles is T_num, the pulse cycle time T satisfies: 5 minutes ≤ T ≤ 60 minutes, and the number of pulse cycles T_num satisfies: 2 ≤ T_num ≤ 20;

[0027] Among them, a pulse cycle includes two steps. The first step is the defluorination reaction process of the crackable hydrogen-containing gas. The defluorination reaction time of the crackable hydrogen-containing gas is t1 minutes, and the flow rate of the crackable hydrogen-containing gas is V1 cubic meters / minute. The second step is the inert carrier gas replacement process. The inert carrier gas replacement time is t2 minutes, and the inert carrier gas flow rate is V2 cubic meters / minute. t1 and t2 satisfy: 0.1≤t1 / t2≤10, V1 and V2 satisfy: 1≤(V1*t1) / (V2*t2)≤10.

[0028] Among them, the crackable hydrogen-containing gas refers to one or a mixture of more than one of hydrogen, hydrocarbon organic gas, water vapor, alcohol organic gas, acid organic gas, ester organic gas, and carbonate organic gas; the inert gas refers to one or a mixture of more than one of nitrogen, helium, and argon; the total pretreatment time t satisfies: 30 minutes ≤ t ≤ 180 minutes, and the pretreatment temperature Temp satisfies: 500°C ≤ Temp ≤ 650°C.

[0029] In the embodiment of the present application, at a preset temperature Temp, the introduced decomposable hydrogen-containing gas is catalytically decomposed to release hydrogen atoms, and a defluorination chemical reaction is carried out based on the released hydrogen atoms and the fluorine atoms or metal fluorides produced by the decomposition of the fluorine-containing substances in the waste lithium battery core raw materials, thereby achieving the removal of fluorine in the waste lithium battery core raw materials, wherein:

[0030] The catalytic cracking chemical reaction formula for cracking hydrogen-containing gas is as follows:

[0031] RH(g)=H·(g)+R·(g) (1)

[0032] The chemical reaction formula of defluorination reaction is as follows:

[0033] H·(g)+F·(g)=HF(g) (2)

[0034] H·(g)+OH·(g)+LiF=HF(g)+LiOH (3).

[0035] In the embodiment of the present application, based on multiple periodic pulse modes, the thermal decomposition of the binder in the electrode active material can be enhanced, and the hydrogen atoms generated by the catalytic cracking of the introduced decomposable hydrogen-containing gas at a preset temperature form a reducing atmosphere, so that the surface of the waste lithium battery core material is affected by the reducing atmosphere, and the bonding force between the electrode active material and the foil surface is greatly weakened, thereby reducing the bonding force between the electrode active material and the surface of the waste lithium battery core material, improving the stripping effect of the electrode active material, making the electrode active material easy to separate from the surface of the lithium battery black powder core material, and the copper and aluminum content in the lithium battery black powder obtained after pretreatment can reach less than 0.1%, thereby realizing the efficient separation of copper and aluminum in the waste lithium battery core material; at the same time, multiple cycles of defluorination reaction of decomposable hydrogen-containing gas and inert carrier gas replacement treatment effectively promote the defluorination reaction and inhibit the solid fluorine reaction, thereby achieving the implementation effect of rapid reaction generation and rapid removal of gas-phase fluoride, and realizing efficient and deep removal of fluorine in lithium battery black powder. Therefore, the pulse pretreatment method for waste lithium battery cores provided in the present application has the characteristics of high defluorination rate, high efficiency and low cost, and has significant cost advantages compared with existing traditional process methods.

[0036] Since the hydrogen fluoride gas generated in the defluorination reaction has a high chemical reactivity, it is easy to react with the metal elements in the electrode active material to generate metal fluorides, that is, a "fluorine fixation" side reaction occurs. The chemical reaction formula of the fluorine fixation reaction is as follows:

[0037]

[0038] In formula (4) and formula (5), Me represents metal elements such as Fe, Cu, Al, Ni, Co, and Mn. In order to reduce the occurrence of the "fluorine fixation" side reaction in formula (4) and formula (5), in this embodiment, within one pulse cycle, the defluorination reaction is first carried out, and then the inert carrier gas is used for replacement. The inert carrier gas can quickly remove the HF gas generated by the defluorination reaction process of the decomposable hydrogen-containing gas, and the concentration of the reactants in the "fluorine fixation" reaction is reduced to suppress the occurrence of side reactions; in order to achieve a deep defluorination effect, this embodiment adopts a multiple-cycle enhanced pulse method to remove the fluorine content in the waste lithium battery core raw material step by step, and at the same time, the effect of fully removing the organic solvent and fully decomposing the binder is also achieved simultaneously.

[0039] In this embodiment, each pulse period can be any value between 5-60min, for example, it can be 5min, 10min, 15min, 20min, 25min, 30min, 35min, 40min, 45min, 50min, 55min, 60min, etc., and the number of pulse periods can be any value between 2-20, for example, it can be 2, 5, 8, 11, 14, 17, 20, etc. In practical application, the time of each pulse period needs to be set according to the actual situation. If the time is set too short, it is beneficial to inhibit the solid fluorine reaction in a short time, but the reaction time of the cracked hydrogen-containing gas and the fluorine in the waste lithium battery core raw material is insufficient, and the defluorination effect may be poor; if the time is set too long, the reaction time of the cracked hydrogen-containing gas and the fluorine in the waste lithium battery core raw material is sufficient, but it is not conducive to inhibiting the solid fluorine reaction, and the defluorination effect is also poor; at the same time, if the number of pulse periods is too large, it takes too long, which is not conducive to improving work efficiency, and if the number of pulse periods is too small, it is not conducive to the defluorination effect. Therefore, the time and number of each pulse cycle should be adjusted according to the actual removal effect.

[0040] In some embodiments, the process further includes sorting the waste lithium battery core raw materials after periodic pulse pretreatment to obtain metallic copper, metallic aluminum and lithium battery black powder.

[0041] In the above embodiment, by sorting the waste lithium battery core raw materials after periodic pulse pretreatment, lithium battery black powder, metallic copper and metallic aluminum are finally obtained, thereby achieving efficient separation of fluorine, copper, aluminum and waste lithium battery core raw materials, and providing a guarantee for the subsequent further recycling of lithium battery black powder.

[0042] The following examples describe the disclosure of the present application in more detail, and these examples are merely illustrative, as it will be apparent to those skilled in the art that various modifications and variations within the scope of the disclosure of the present application are possible. Unless otherwise stated, all reagents and raw materials used in the examples are commercially available or synthesized according to conventional methods, and the instruments and equipment used in the examples are commercially available.

[0043] Example 1

[0044] 1) The waste lithium battery is dissected, the pole core is taken out, and 1000 kg of the pole core is sent to a pretreatment reaction device with a preset temperature of Temp = 500 ° C and the first pulse cycle pretreatment is performed. First, water vapor with a flow rate of V1 = 9.6 m3 / min is input into the pretreatment reaction device. The input water vapor fully contacts with the waste lithium battery pole core and performs a defluorination reaction. The defluorination reaction time is t1 = 20 minutes; then the water vapor is stopped, and nitrogen with a flow rate of V2 = 8 m3 / min is switched to be replaced as a carrier gas. The nitrogen replacement time is t2 = 10 minutes. The time of the first pulse cycle is T = t1 + t2 = 30 minutes, which satisfies 5 minutes ≤ T ≤ 60 minutes; the second pulse cycle pretreatment and the third pulse cycle pretreatment are performed in sequence in the same steps, and the waste lithium battery pole core after the pulse pretreatment is cooled to room temperature;

[0045] 2) The cooled waste lithium battery core is sorted into metal copper, metal aluminum and battery black powder, and finally lithium battery black powder, metal copper and metal aluminum are obtained.

[0046] In this embodiment, the number of periodic pulses Tnum=3, satisfying 2≤Tnum≤20; the defluorination reaction time and the inert carrier gas replacement time t1 / t2=2, satisfying 0.1≤t1 / t2≤10; the relationship between the flow rate of the crackable hydrogen-containing gas, the flow rate of the inert carrier gas, the defluorination reaction time and the carrier gas replacement time is: (V1*t1) / (V2*t2)=2.4, satisfying 1≤(V1*t1) / (V2*t2)≤10; the total pretreatment time t=90 minutes, satisfying 30 minutes≤t≤180 minutes.

[0047] Example 2

[0048] 1) Dissect the waste lithium battery, take out the pole core, and send 1000 kg of the pole core into a pretreatment reaction device with a preset temperature of Temp = 600 ° C and perform the first pulse cycle pretreatment. First, input natural gas with a flow rate of V1 = 2.2 m3 / min into the pretreatment reaction device, and the input water vapor fully contacts with the waste lithium battery pole core and performs a defluorination reaction. The defluorination reaction time is t1 = 10 minutes; then stop introducing natural gas, switch to nitrogen with a flow rate of V2 = 4 m3 / min as a carrier gas and replace it. The nitrogen replacement time is t2 = 5 minutes. The time of the first pulse cycle is T = t1 + t2 = 15 minutes, which satisfies 5 minutes ≤ T ≤ 60 minutes; perform the second pulse cycle pretreatment, the third pulse cycle pretreatment and the fourth pulse cycle pretreatment in the same steps, and cool the waste lithium battery pole core after the pulse pretreatment to room temperature;

[0049] 2) The cooled waste lithium battery core is sorted into metal copper, metal aluminum and battery black powder, and finally lithium battery black powder, metal copper and metal aluminum are obtained.

[0050] In this embodiment, the number of periodic pulses Tnum=4, satisfying 2≤Tnum≤20; the defluorination reaction time and the inert carrier gas replacement time t1 / t2=2, satisfying 0.1≤t1 / t2≤10; the relationship between the flow rate of the crackable hydrogen-containing gas, the flow rate of the inert carrier gas, the defluorination reaction time and the carrier gas replacement time is: (V1*t1) / (V2*t2)=1.1, satisfying 1≤(V1*t1) / (V2*t2)≤10; the total pretreatment time t=60 minutes, satisfying 30 minutes≤t≤180 minutes.

[0051] Example 3

[0052] 1) The waste lithium battery is dissected, the pole core is taken out, and 1000 kg of the pole core is sent to a pretreatment reaction device with a preset temperature of Temp = 650 ° C and the first pulse cycle pretreatment is performed. First, a mixed gas with a flow rate of V1 = 38.5m3 / min is input into the pretreatment reaction device, and the mixed gas includes water vapor and natural gas with a volume ratio of 95:5. The input mixed gas is fully in contact with the waste lithium battery pole core and undergoes a defluorination reaction. The defluorination reaction time is t1 = 10 minutes; then the introduction of the mixed gas is stopped, and nitrogen with a flow rate of V2 = 9m3 / min is switched to be replaced as a carrier gas. The nitrogen replacement time is t2 = 5 minutes. The time of the first pulse cycle is T = t1 + t2 = 15 minutes, which satisfies 5 minutes ≤ T ≤ 60 minutes; the second pulse cycle pretreatment, the third pulse cycle pretreatment, the fourth pulse cycle pretreatment and the fifth pulse cycle pretreatment are sequentially performed in the same steps, and the waste lithium battery pole core after the pulse pretreatment is cooled to room temperature;

[0053] 2) The cooled waste lithium battery core is sorted into metal copper, metal aluminum and battery black powder, and finally lithium battery black powder, metal copper and metal aluminum are obtained.

[0054] In this embodiment, the number of periodic pulses Tnum=5, satisfying 2≤Tnum≤20; the defluorination reaction time and the inert carrier gas replacement time t1 / t2=2, satisfying 0.1≤t1 / t2≤10; the relationship between the flow rate of the crackable hydrogen-containing gas, the flow rate of the inert carrier gas, the defluorination reaction time and the carrier gas replacement time is: (V1*t1) / (V2*t2)=8.6, satisfying 1≤(V1*t1) / (V2*t2)≤10; the total pretreatment time t=75 minutes, satisfying 30 minutes≤t≤180 minutes.

[0055] The lithium battery black powder obtained in Examples 1-3 was tested for fluorine, aluminum and copper content, and the test results are shown in Table 1.

[0056] Table 1 Detection results of fluorine, aluminum and copper content of lithium battery black powder in Examples 1-3

[0057] F(％) Al(％) Cu(%) Example 1 0.036 0.073 0.082 Example 2 0.043 0.076 0.085 Example 3 0.027 0.056 0.064

[0058] It can be seen from Table 1 that the fluorine content, aluminum content and copper content in the lithium battery black powder obtained in Example 1, Example 2 and Example 3 are all below 0.1%, indicating that Examples 1-3 all achieve effective separation and removal of fluorine, copper and aluminum in the waste lithium battery core raw materials. Therefore, the pulse pretreatment method provided in the present application can effectively remove the fluorine, copper and aluminum elements in the lithium battery black powder, which reduces the control and treatment costs of fluorine, copper and aluminum in subsequent processes, has the characteristics of high efficiency and low cost, and provides favorable conditions for the subsequent recovery and treatment of lithium battery black powder.

[0059] The above is a detailed introduction to the pulse pretreatment method for waste lithium battery cores provided by the present application. This article uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the core idea of ​​the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A pulse pretreatment method for waste lithium battery cores, characterized in that: The method comprises: At the set pretreatment temperature Temp, the waste lithium battery core is subjected to pulsed thermal defluorination and replacement treatment, the total pretreatment time is t minutes, one pulse cycle time is T minutes, the number of pulse cycles is T_num, the pulse cycle time T satisfies: 5 minutes ≤ T ≤ 60 minutes, and the number of pulse cycles T_num satisfies: 2 ≤ T_num ≤ 20; Among them, a pulse cycle includes two steps. The first step is the defluorination reaction process of the crackable hydrogen-containing gas. The defluorination reaction time of the crackable hydrogen-containing gas is t1 minutes, and the flow rate of the crackable hydrogen-containing gas is V1 cubic meters / minute. The second step is the inert carrier gas replacement process. The inert carrier gas replacement time is t2 minutes, and the inert carrier gas flow rate is V2 cubic meters / minute. t1 and t2 satisfy: 0.1≤t1 / t2≤10, V1 and V2 satisfy: 1≤(V1*t1) / (V2*t2)≤10.

2. The pulse pretreatment method for waste lithium battery cores according to claim 1, characterized in that: The total pretreatment time t satisfies: 30 minutes ≤ t ≤ 180 minutes, and the pretreatment temperature Temp satisfies: 500° C. ≤ Temp ≤ 650° C.

3. The pulse pretreatment method for waste lithium battery cores according to claim 1 or 2, characterized in that: The crackable hydrogen-containing gas refers to one or a mixture of more than one of hydrogen, hydrocarbon organic gas, water vapor, alcohol organic gas, acid organic gas, ester organic gas, and carbonate organic gas; the inert gas refers to one or a mixture of more than one of nitrogen, helium, and argon.

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