A method and system for deep discharge safety passivation of waste power batteries

Abstract

The present invention discloses a method for safe deep discharge passivation of waste power batteries, comprising the following steps: performing appearance cleaning on the waste power batteries to obtain cleaned waste power batteries; performing preliminary discharge on the cleaned waste power batteries after drying to obtain preliminary discharged waste power batteries; performing forced discharge passivation on the preliminary discharged waste power batteries until the safety passivation cut-off condition is reached, thereby completing the deep discharge safe passivation of the waste power batteries. The present invention also discloses a system for implementing the method for safe deep discharge passivation of waste power batteries. The method of the present invention realizes the safe deep discharge passivation of waste power batteries, and improves the economic efficiency of battery positive electrode recycling and the safety of the recycling process.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery recycling, and in particular relates to a method and system for deep discharge safety passivation of waste power batteries. Background Art

[0002] As the market size of power battery vehicles based on lithium iron phosphate battery systems gradually expands, battery safety recycling has gradually become the focus of the industry. As the next generation of lithium iron phosphate cathode recycling technology, deep discharge is more economical, efficient, and green than the existing salt water discharge process.

[0003] However, there is great uncertainty in the recycling products and recycling safety during deep discharge between different battery batches. Excessive deep discharge will not only lead to the loss of the final recycling products, but also may cause safety risks.

[0004] Therefore, there is an urgent need for a method to deeply discharge waste power batteries and safely passivate them. Summary of the invention

[0005] One of the purposes of the present invention is to provide a deep discharge safety passivation method for waste power batteries, which divides different passivation reaction intervals by the battery deep discharge curve, and then calibrates the safe passivation target area by characterizing the chemical reactions of the battery positive electrode in different reaction intervals, extracts the change law between the reactants and the electrochemical characteristics from the specific electrochemical reaction characteristics, and establishes a deep discharge safety passivation control model for waste power batteries. The battery safe passivation interval is controlled by the model, and the generation of reactants is controlled to a certain extent, thereby improving the economy and safety of battery positive electrode recovery.

[0006] A second object of the present invention is to provide a system for implementing the deep discharge safety passivation method of waste power batteries.

[0007] The present invention provides a method for deep discharge safety passivation of waste power batteries, comprising the following steps:

[0008] S1. Cleaning the appearance of the used power battery to obtain the cleaned used power battery;

[0009] S2. The cleaned used power battery is dried and then initially discharged to obtain a preliminarily discharged used power battery;

[0010] S3. Perform forced discharge passivation on the initially discharged used power batteries until the safety passivation cut-off conditions are met, thus completing the deep discharge safety passivation of the used power batteries.

[0011] Step S1 specifically includes: cleaning the appearance of the used power battery by a cleaning mechanism, filtering the sewage or waste gas formed after cleaning, and recycling and reusing the cleaned used power battery.

[0012] Step S2 specifically includes: drying the cleaned used power battery and then using an external load circuit to discharge the battery to a cut-off voltage of 2V to obtain a preliminarily discharged used power battery; the discharge rate range is 0.5C~4C.

[0013] Step S3 is specifically as follows: using an external power source to perform forced discharge passivation on the preliminarily discharged used power battery, controlling the discharge process to reach the safe passivation cut-off condition, and completing deep discharge safe passivation of the used power battery; the discharge rate range is 0.05C~0.5C; and forced discharge is achieved by a switching power supply.

[0014] The control of the discharge process to achieve the safe passivation cut-off condition is achieved by the following steps:

[0015] S11. Collect the voltage and power values ​​of the positive and negative electrodes of the waste power battery, draw the electrochemical curve of the negative electrode of the waste power battery, and obtain the electrochemical characteristic of the battery;

[0016] S12. Based on the electrochemical characteristic quantity of the battery obtained in step S11, a curve of the change in power and the electrochemical characteristic quantity of the battery is drawn as a training data set;

[0017] S13. Based on a data-driven approach, including but not limited to CNN and its variants, RNN and its variants, genetic algorithms and other deep learning or meta-heuristic algorithm frameworks, construct an initial safety passivation condition judgment model; using the training data set obtained in step S12, the initial safety passivation condition judgment model is trained to obtain a safety passivation condition judgment model;

[0018] S14. According to step S13, a safety passivation condition judgment model is obtained to perform actual deep discharge safety passivation of the waste power battery.

[0019] Step S11 specifically includes the following steps:

[0020] Record the positive and negative electrode voltage values ​​V and the electric quantity Q of the waste power battery during the entire discharge process, and draw the electrochemical curve of the negative electrode of the waste power battery;

[0021] According to the discharge reaction products, the negative electrode electrochemical curve of the power battery deep discharge is divided into 4 intervals: [positive infinity, 2V], [2V, 0V], [0V, -1V], [-1, negative infinity]; among them, above 0V is the working condition detection interval, and below 0V is the core control interval;

[0022] According to the phase change of discharge reactants, the safety passivation cut-off characteristics of waste power batteries are obtained as follows: after the anode copper is precipitated and before the cathode copper is reduced;

[0023] According to the electrochemical curve of the negative electrode of the waste power battery, the battery capacity change dQ, the battery voltage change dV, the change ratio dV / dQ and the change of the change ratio d (dV / dQ) are calculated.

[0024] Step S12 is specifically as follows:

[0025] According to the battery electrochemical characteristic quantity obtained in step S11, a curve of the change of the quantity Q and the battery electrochemical characteristic quantity is drawn;

[0026] According to the safety passivation cut-off characteristics of step S11, the cut-off condition of the battery electrochemical characteristic quantity is obtained, specifically: the corresponding battery electrochemical characteristic quantity is obtained, between the first maximum point after the dV / dQ curve is less than 0V and the second point greater than 0;

[0027] The variation curves of the quantity Q and the electrochemical characteristic quantities of the battery and the corresponding cutoff condition calibration are converted into a data sample set to obtain a training data set.

[0028] Step S14 includes the following steps:

[0029] a. Clean the appearance of the used power batteries to be recycled, discharge them with external loads and external power supplies;

[0030] b. Real-time collection of the positive and negative electrode voltage values ​​V and the power Q of the current waste power battery, and drawing the electrochemical curve of the negative electrode of the waste power battery;

[0031] c. Calculate the electrochemical characteristic quantities of the battery according to the electrochemical curve of the negative electrode of the waste power battery, including the battery capacity change dQ, the battery voltage change dV, the change ratio dV / dQ and the change of the change ratio d (dV / dQ);

[0032] d. According to the electrochemical characteristic quantity of the battery, draw a curve of the change of the quantity Q and the electrochemical characteristic quantity of the battery;

[0033] e. Input the electric quantity Q and the battery electrochemical curve as data sample features into the safety passivation condition judgment model obtained in step S13 to determine whether the safety passivation condition is met. If the safety passivation cut-off condition is met, the waste power battery is controlled to stop discharging and complete the deep discharge safety passivation of the waste power battery; otherwise, return to step b.

[0034] Step S14 is specifically as follows:

[0035] Step a specifically comprises: cleaning the appearance of the used power battery to be recycled by a cleaning mechanism, filtering the sewage or waste gas formed after cleaning, and recycling it to obtain the cleaned used power battery; drying the cleaned used power battery, discharging the battery to a cut-off voltage of 2V using an external load circuit, and then using an external power supply to force discharge passivation of the preliminarily discharged used power battery;

[0036] Step e is specifically as follows: the electric quantity Q and the battery electrochemical curve are input as data sample features into the safety passivation condition judgment model obtained in step S13 to judge whether the safety passivation condition is met. If the safety passivation cut-off condition is met, proceed to the next step; otherwise, return to step b; control the waste power battery to stop discharging, complete the deep discharge safety passivation of the waste power battery, and store the data point of the waste power battery discharged this time as the deep discharge cut-off point of the power battery safety passivation under similar working conditions.

[0037] The present invention also provides a system for implementing the deep discharge safety passivation method for waste power batteries, including a battery cleaning module, a preliminary discharge module, and a deep discharge safety passivation module;

[0038] The battery cleaning module cleans the appearance of the waste power battery to obtain the cleaned waste power battery;

[0039] The preliminary discharge module dries the cleaned waste power battery and then performs preliminary discharge through the preliminary discharge module to obtain a preliminarily discharged waste power battery; the structure used in the preliminary discharge module includes but is not limited to a switching power supply, a MOS tube or a thermal resistor;

[0040] The deep discharge safety passivation module performs forced discharge passivation on the initially discharged used power batteries until the safety passivation cut-off condition is reached, thus completing the deep discharge safety passivation of the used power batteries.

[0041] Beneficial effects of the invention: The invention discloses a process control method and system for deep discharge safety passivation of waste power batteries. The battery can be divided into different passivation reaction intervals through the battery deep discharge curve. The chemical reactions of the battery positive electrode in different reaction intervals are characterized to calibrate the safety passivation target area. The change law between the reactants and the electrochemical characteristics is extracted from the specific electrochemical reaction characteristics. A deep discharge safety passivation control model and method for waste power batteries are established to control the battery safety passivation interval and to control the generation of reactants to a certain extent, thereby improving the economy and safety of battery positive electrode recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic diagram of the process of the present invention;

[0043] Figure 2It is a structural schematic diagram of the system of the present invention;

[0044] Figure 3 Schematic diagram of the electrochemical curve and discharge cut-off interval of the waste power battery in the embodiment of the present invention;

[0045] Figure 4 CV curve of charge and discharge of waste power battery in the embodiment of the present invention;

[0046] Figure 5 The dV / dQ curve of the electrochemical characteristic quantity during the charge and discharge process of the waste power battery in the embodiment of the present invention;

[0047] Figure 6 The open circuit voltage variation curve of the waste power battery during the charging and discharging process in the embodiment of the present invention;

[0048] Figure 7 This is a graph showing the changes in the composition of the positive electrode material during the charge and discharge process of the waste power battery in an embodiment of the present invention;

[0049] Figure 8 This is a physical picture of the positive and negative electrode surfaces of the waste power battery after deep discharge in the embodiment of the present invention; wherein, Figure 8 a is the winding core after forced discharge, Figure 8 b is the positive electrode after forced discharge. Figure 8 c is the negative electrode sheet after forced discharge;

[0050] Fig. 9 It is a reaction interval diagram of the potential characteristic quantity of the waste power battery in the embodiment of the present invention. DETAILED DESCRIPTION

[0051] The present invention provides a method for deep discharge safety passivation of waste power batteries, comprising the following steps:

[0052] S1. Clean the appearance of the used power battery to obtain the cleaned used power battery, specifically:

[0053] The appearance of the used power battery is cleaned by a cleaning mechanism, and the sewage or waste gas formed after cleaning is filtered and recycled to obtain the cleaned used power battery.

[0054] S2. The cleaned used power battery is dried and then preliminarily discharged to obtain a preliminarily discharged used power battery, specifically:

[0055] After the cleaned used power battery is dried, the battery is discharged to a cut-off voltage of 2V using an external load circuit to obtain a preliminarily discharged used power battery; the discharge rate is 0.5C~4C; the load of the external load circuit used includes but is not limited to a switching power supply, a MOS tube or a thermal resistor.

[0056] S3. Perform forced discharge passivation on the initially discharged waste power batteries until the safety passivation cut-off conditions are met, and complete the deep discharge safety passivation of the waste power batteries, specifically:

[0057] Use an external power source to force discharge passivation on the initially discharged waste power batteries, control the discharge process to reach the safe passivation cut-off condition, and complete the deep discharge safety passivation of the waste power batteries; the discharge rate is 0.05C~0.5C; forced discharge is achieved through a switching power supply.

[0058] The control of the discharge process to achieve the safe passivation cut-off condition is achieved by the following steps:

[0059] S11. Collect the voltage and power values ​​of the positive and negative electrodes of the waste power battery, draw the electrochemical curve of the negative electrode of the waste power battery, and obtain the electrochemical characteristic of the battery;

[0060] S12. Based on the electrochemical characteristic quantity of the battery obtained in step S11, a curve of the change in power and the electrochemical characteristic quantity of the battery is drawn as a training data set;

[0061] S13. Based on a data-driven approach, including but not limited to CNN and its variants, RNN and its variants, genetic algorithms and other deep learning or meta-heuristic algorithm frameworks, construct an initial safety passivation condition judgment model; using the training data set obtained in step S12, the initial safety passivation condition judgment model is trained to obtain a safety passivation condition judgment model;

[0062] S14. According to step S13, a safety passivation condition judgment model is obtained to perform actual deep discharge safety passivation of the waste power battery.

[0063] Step S11 specifically includes the following steps:

[0064] Record the positive and negative electrode voltage values ​​V and the electric quantity Q of the waste power battery during the entire discharge process, and draw the electrochemical curve of the negative electrode of the waste power battery;

[0065] According to the discharge reaction products, the negative electrode electrochemical curve of the power battery deep discharge is divided into 4 intervals: [positive infinity, 2V], [2V, 0V], [0V, -1V], [-1, negative infinity]; among them, above 0V is the working condition detection interval, and below 0V is the core control interval;

[0066] According to the phase change of discharge reactants, the safety passivation cut-off characteristics of waste power batteries are obtained as follows: after the anode copper is precipitated and before the cathode copper is reduced;

[0067] According to the electrochemical curve of the negative electrode of the waste power battery, the battery capacity change dQ, the battery voltage change dV, the change ratio dV / dQ and the change of the change ratio d (dV / dQ) are calculated.

[0068] Step S12 is specifically as follows:

[0069] According to the battery electrochemical characteristic quantity obtained in step S11, a curve of the change of the quantity Q and the battery electrochemical characteristic quantity is drawn;

[0070] According to the safety passivation cut-off characteristics of step S11, the cut-off condition of the battery electrochemical characteristic quantity is obtained, specifically: the corresponding battery electrochemical characteristic quantity is obtained, between the first maximum point after the dV / dQ curve is less than 0V and the second point greater than 0;

[0071] The variation curves of the quantity Q and the electrochemical characteristic quantities of the battery and the corresponding cutoff condition calibration are converted into a data sample set to obtain a training data set.

[0072] Step S14 includes the following steps:

[0073] a. Clean the appearance of the used power batteries to be recycled, discharge them with external loads and external power supplies;

[0074] b. Real-time collection of the positive and negative electrode voltage values ​​V and the power Q of the current waste power battery, and drawing the electrochemical curve of the negative electrode of the waste power battery;

[0075] c. Calculate the electrochemical characteristic quantities of the battery according to the electrochemical curve of the negative electrode of the waste power battery, including the battery capacity change dQ, the battery voltage change dV, the change ratio dV / dQ and the change of the change ratio d (dV / dQ);

[0076] d. According to the electrochemical characteristic quantity of the battery, draw a curve of the change of the quantity Q and the electrochemical characteristic quantity of the battery;

[0077] e. Input the electric quantity Q and the battery electrochemical curve as data sample features into the safety passivation condition judgment model obtained in step S13 to determine whether the safety passivation condition is met. If the safety passivation cut-off condition is met, the waste power battery is controlled to stop discharging and complete the deep discharge safety passivation of the waste power battery; otherwise, return to step b.

[0078] Step S14 is specifically as follows:

[0079] Step a specifically comprises: cleaning the appearance of the used power battery to be recycled by a cleaning mechanism, filtering the sewage or waste gas formed after cleaning, and recycling it to obtain the cleaned used power battery; drying the cleaned used power battery, discharging the battery to a cut-off voltage of 2V using an external load circuit, and then using an external power supply to force discharge passivation of the preliminarily discharged used power battery;

[0080] Step e is specifically as follows: the electric quantity Q and the battery electrochemical curve are input as data sample features into the safety passivation condition judgment model obtained in step S13 to judge whether the safety passivation condition is met. If the safety passivation cut-off condition is met, proceed to the next step; otherwise, return to step b; control the waste power battery to stop discharging, complete the deep discharge safety passivation of the waste power battery, and store the data point of the waste power battery discharged this time as the deep discharge cut-off point of the power battery safety passivation under similar working conditions.

[0081] The present invention also provides a system for implementing the deep discharge safety passivation method for waste power batteries, including a battery cleaning module, a preliminary discharge module, and a deep discharge safety passivation module;

[0082] The battery cleaning module cleans the appearance of the waste power battery to obtain the cleaned waste power battery;

[0083] The preliminary discharge module dries the cleaned waste power battery and then performs preliminary discharge through the preliminary discharge module to obtain a preliminarily discharged waste power battery; the structure used in the preliminary discharge module includes but is not limited to a switching power supply, a MOS tube or a thermal resistor;

[0084] The deep discharge safety passivation module performs forced discharge passivation on the initially discharged used power batteries until the safety passivation cut-off condition is reached, thus completing the deep discharge safety passivation of the used power batteries.

[0085] The method of the present invention is further described below in conjunction with an embodiment:

[0086] Two aged batteries from the same batch with similar capacity and internal resistance were selected, and discharged with a current of 1600mA (1C) to a cut-off voltage of 2V. Then, they were discharged with a current of 800mA (0.5C) to a cut-off voltage of 2V using the system proposed in the present invention, and finally discharged with a current of 160mA (0.1C).

[0087] During the discharge process, the system proposed by the present invention is used to collect the real-time voltage and real-time power value of the positive and negative electrodes of the waste power battery, and to draw the electrochemical curve of the negative electrode of the waste power battery; the battery capacity change dQ, the battery real-time voltage change dV, dQ / dV, d(dQ / dV), etc. in the current state are calculated at intervals of 15 sampling points (15s); the model of the present invention is used to determine whether the safety passivation cut-off condition is reached, and the deep discharge process is controlled until the copper precipitation point of the OCV DQ / DV-Capacity curve is cut off.

[0088] Among them, the electrochemical curve of the waste power battery and the schematic diagram of the discharge cut-off interval are as follows: Figure 3 As shown; the charge and discharge CV curve of the waste power battery is as follows Figure 4As shown in the figure; the electrochemical characteristic dV / dQ curve of the waste power battery during the charging and discharging process is as follows Figure 5 As shown in the figure, the horizontal axis is the capacity of the waste power battery, the vertical axis is the electrochemical characteristic quantity dV / dQ, and the point marked in the figure is the starting point of copper precipitation; the open circuit voltage change curve of the waste power battery during charging and discharging is shown in the figure Figure 6 As shown in the figure, the vertical axis is the open circuit voltage of the waste power battery, and the horizontal axis is the capacity of the waste power battery; the change of the positive electrode material composition during the charge and discharge process of the waste power battery is shown in the figure Figure 7 As shown, the strip Li-Concentration is the lithium content in the positive electrode material, the strip Cu-Concentration is the copper content in the positive electrode material, the horizontal axis Sta represents the positive electrode condition after discharge using the conventional method, and NCu represents the positive electrode condition after discharge using the method of the present invention; the actual surface of the positive and negative electrodes of the waste power battery after charge and discharge is shown in Figure 8 As shown, Figure 8 a is the winding core after forced discharge, Figure 8 b is the positive electrode after forced discharge. Figure 8 c is the negative electrode after forced discharge; the reaction interval diagram of the potential characteristic quantity of the waste power battery is as follows Fig. 9 shown.

Claims

1. A deep discharge safety passivation method for waste power batteries, characterized in that: The following steps are involved: S1. Cleaning the appearance of the used power battery to obtain the cleaned used power battery; S2. The cleaned used power battery is dried and then initially discharged to obtain a preliminarily discharged used power battery; S3. Perform forced discharge passivation on the initially discharged waste power batteries until the safety passivation cut-off condition is reached, completing the deep discharge safety passivation of the waste power batteries; The electrochemical reaction characteristics of the safety passivation cut-off condition of the waste power battery are: after the anode copper is precipitated and before the cathode copper is reduced; Step S3 is implemented by the following steps: S11. Collect the voltage and power of the positive and negative electrodes of the waste power battery, draw the electrochemical curve of the negative electrode of the waste power battery, and obtain the electrochemical characteristics of the battery; the electrochemical characteristics of the battery include the battery capacity change dQ, the battery voltage change dV, the change ratio dV / dQ and the change ratio ; S12. Based on the battery electrochemical characteristic quantity obtained in step S11, a curve of the change in power and the battery electrochemical characteristic quantity is drawn as a training data set; step S12 is specifically as follows: According to the battery electrochemical characteristic quantity obtained in step S11, a curve of the change of the quantity Q and the battery electrochemical characteristic quantity is drawn; According to the electrochemical reaction characteristics of the safety passivation cut-off condition, the cut-off condition of the battery electrochemical characteristic quantity is obtained, specifically: the corresponding battery electrochemical characteristic quantity is obtained, between the first maximum point of the dV / dQ curve after the open circuit voltage is less than 0V and the second point greater than 0; The variation curve of the quantity Q and the electrochemical characteristic quantity of the battery and the corresponding cut-off condition calibration are converted into a data sample set to obtain a training data set; S13 based on a data-driven approach, which includes deep learning or meta-heuristic algorithm framework, to build an initial safety passivation condition judgment model; using the training data set obtained in step S12, the initial safety passivation condition judgment model is trained to obtain a safety passivation condition judgment model; S14. Obtain the safety passivation condition judgment model according to step S13, obtain the change curve of the power Q of the used power battery to be recycled and the electrochemical characteristic quantity of the battery, and input it into the safety passivation condition judgment model obtained in step S13 as the data sample feature to judge whether the safety passivation condition is met. If the safety passivation cut-off condition is met, control the used power battery to stop discharging, and complete the deep discharge safety passivation of the used power battery.

2. The deep discharge safety passivation method for waste power batteries according to claim 1, characterized in that: Step S1 specifically includes: cleaning the appearance of the used power battery by a cleaning mechanism, filtering the sewage or waste gas formed after cleaning, and recycling and reusing the cleaned used power battery.

3. The deep discharge safety passivation method for waste power batteries according to claim 1, characterized in that: Step S2 specifically includes: drying the cleaned used power battery, and then using an external load circuit to discharge the dried used power battery to a cut-off voltage of 2V to obtain a preliminarily discharged used power battery; the discharge rate range is 0.5C~4C.

4. The deep discharge safety passivation method for waste power batteries according to claim 1 is characterized in that: Step S3 is specifically as follows: using an external power source to perform forced discharge passivation on the preliminarily discharged used power battery, controlling the discharge process to reach the safe passivation cut-off condition, and completing deep discharge safe passivation of the used power battery; the discharge rate range is 0.05C~0.5C; and forced discharge is achieved by a switching power supply.

5. The deep discharge safety passivation method for waste power batteries according to claim 1 is characterized in that: Step S11 specifically includes the following steps: Record the positive and negative electrode voltage values ​​V and the electric quantity Q of the waste power battery during the entire discharge process, and draw the electrochemical curve of the negative electrode of the waste power battery; According to the discharge reaction products, the negative electrode electrochemical curve of the power battery deep discharge is divided into 4 intervals: [positive infinity, 2V], [2V, 0V], [0V, -1V], [-1, negative infinity]; among them, above 0V is the working condition detection interval, and below 0V is the core control interval; According to the electrochemical curve of the negative electrode of the waste power battery, calculate the battery capacity change dQ, battery voltage change dV, change ratio dV / dQ and change of the change ratio .

6. The deep discharge safety passivation method for waste power batteries according to claim 1 is characterized in that: Step S14 includes the following steps: a. Clean the appearance of the used power batteries to be recycled, discharge them with external loads and external power supplies; b. Real-time collection of the positive and negative electrode voltage values ​​V and the power Q of the current waste power battery, and drawing the electrochemical curve of the negative electrode of the waste power battery; c. Calculate the electrochemical characteristics of the battery based on the electrochemical curve of the negative electrode of the waste power battery, including the battery capacity change dQ, battery voltage change dV, change ratio dV / dQ and change of the change ratio ; d. According to the electrochemical characteristic quantity of the battery, draw a curve of the change of the quantity Q and the electrochemical characteristic quantity of the battery; e. Input the change curve of the electric quantity Q and the electrochemical characteristic quantity of the battery as the data sample feature into the safety passivation condition judgment model obtained in step S13 to judge whether the safety passivation condition is met. If the safety passivation cut-off condition is met, the waste power battery is controlled to stop discharging and complete the deep discharge safety passivation of the waste power battery; otherwise, return to step b.

7. The deep discharge safety passivation method for waste power batteries according to claim 6 is characterized in that: Step S14 is specifically as follows: Step a specifically comprises: cleaning the appearance of the used power battery to be recycled by a cleaning mechanism, filtering the sewage or waste gas formed after cleaning, and recycling it to obtain the cleaned used power battery; drying the cleaned used power battery, discharging the battery to a cut-off voltage of 2V using an external load circuit, and then using an external power supply to force discharge passivation of the preliminarily discharged used power battery; Step e specifically includes: inputting the change curve of the electric quantity Q and the electrochemical characteristic quantity of the battery as the data sample feature into the safety passivation condition judgment model obtained in step S13 to judge whether the safety passivation condition is met. If the safety passivation cut-off condition is met, proceed to the next step; Otherwise, return to step b; control the used power battery to stop discharging, complete the deep discharge safety passivation of the used power battery, and store the data point of the used power battery discharged this time as the deep discharge cutoff point of the power battery safety passivation under similar working conditions.

8. A system for implementing the deep discharge safety passivation method for waste power batteries according to any one of claims 1 to 7, characterized in that: The system includes a battery cleaning module, a preliminary discharge module, and a deep discharge safety passivation module; The battery cleaning module cleans the appearance of the waste power battery to obtain the cleaned waste power battery; The preliminary discharge module performs preliminary discharge on the cleaned used power battery after drying, thereby obtaining a preliminarily discharged used power battery; the structure used in the preliminary discharge module includes a switching power supply, a MOS tube or a thermal resistor; The deep discharge safety passivation module performs forced discharge passivation on the initially discharged used power batteries until the safety passivation cut-off condition is reached, thus completing the deep discharge safety passivation of the used power batteries.

Images