Method, system and equipment for recovering working voltage of lithium-rich manganese-based positive electrode and medium

Abstract

The invention discloses a lithium-rich manganese-based positive electrode working voltage recovery method, system and device and a medium, and is applied to the field of lithium batteries. The method provided by the invention comprises the following steps: judging whether the working voltage of a lithium battery corresponding to a lithium-rich manganese-based positive electrode is smaller than the preset working voltage of the lithium battery, and if so, performing a plurality of rounds of first charging operation on the current lithium battery by adopting a first charging parameter after the current lithium battery finishes discharging; charging the current lithium battery to a first preset voltage by each round of first charging operation, and carrying out a plurality of rounds of second charging operation on the current lithium battery by adopting a second charging parameter; each round of second charging operation charges the current lithium battery to a second preset voltage; and discharging the current lithium battery to a third preset voltage by adopting a preset discharge parameter, and detecting the working voltage of the current lithium battery to determine whether the working voltage of the lithium battery is recovered or not. According to the invention, the damaged structure of the lithium-rich manganese-based positive electrode material after long circulation can be recovered, so that the working voltage of the lithium battery is improved.

Description

Technical Field

[0001] The present application relates to the field of lithium batteries, and in particular to a method, system, device and medium for recovering the working voltage of a lithium-rich manganese-based positive electrode. Background Art

[0002] As oil resources become increasingly scarce, energy reforms in the transportation sector are proceeding in an orderly manner. Electric vehicles using power lithium batteries are the mainstream choice among many types of new energy vehicles. As one of the core components of electric vehicles, the energy density of power lithium batteries determines the endurance of the entire vehicle. Only a high enough energy density can eliminate the technical barriers established by the "mileage anxiety" problem. Among them, the capacity of the positive electrode material is the key part that limits the capacity density of power lithium batteries.

[0003] In recent years, lithium-rich manganese-based positive electrode materials can theoretically achieve the construction of 500Wh / kg high energy density battery cells due to their ultra-high discharge specific capacity. However, lithium-rich manganese-based positive electrode materials will have the problem of discharge voltage decay during the cycle process, which is not conducive to the energy density and battery management system of power lithium batteries. A lot of research attempts have been carried out at home and abroad, including doping, surface coating, and composition regulation of lithium-rich manganese-based positive electrode materials. Although these works have alleviated the problem of voltage decay during the cycle to a certain extent, they are often achieved at the expense of ultra-high discharge capacity, which is also not conducive to the improvement of energy density.

[0004] In view of the above technology, seeking a method to restore the operating voltage of lithium-rich manganese-based lithium batteries is an urgent problem to be solved by technicians in this field. Summary of the invention

[0005] The purpose of this application is to provide a method, system, device and medium for recovering the working voltage of a lithium-rich manganese-based positive electrode. The method provided in this application can restore the damaged structure of the lithium-rich manganese-based positive electrode material after a long cycle, thereby increasing the working voltage of the lithium battery corresponding to the lithium-rich manganese-based positive electrode.

[0006] In order to solve the above technical problems, the present application provides a method for recovering the working voltage of a lithium-rich manganese-based positive electrode, comprising:

[0007] Determine whether the current operating voltage of the lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than the preset operating voltage U of the lithium battery, and if so, let the lithium battery stand for a first time t1 after the current lithium battery is discharged;

[0008] Determine a first preset voltage U1, a second preset voltage U2, and a third preset voltage U3;

[0009] Performing several rounds of first charging operations on the current lithium battery using the first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to a first preset voltage U1 and standing for a second time t2;

[0010] Determine the second charging parameter D2 based on the judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and use the second charging parameter D2 to perform several rounds of second charging operations on the current lithium battery; each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3;

[0011] The current lithium battery is discharged to a third preset voltage U3 using a preset discharge parameter D3 and left to stand for a fourth time t4, and then the current working voltage of the current lithium battery is detected to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored.

[0012] Preferably, detecting the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored includes:

[0013] Detect the current working voltage of the current lithium battery to determine the current voltage recovery value;

[0014] If the current voltage recovery value is less than the preset percentage value of the loss voltage, it is determined that the working voltage of the lithium-rich manganese-based positive electrode has not been recovered, and the process jumps again to the step of performing several rounds of first charging operations on the current lithium battery using the first charging parameter D1 at the preset temperature;

[0015] When the current voltage recovery value is not less than a preset percentage value of the loss voltage, it is determined that the working voltage of the lithium-rich manganese-based positive electrode has been recovered.

[0016] Preferably, it also includes:

[0017] If the first preset voltage U1 is equal to the second preset voltage U2, the first charging parameter D1 is configured as a constant first preset charging current value and the preset discharging parameter D3 is configured as a constant first preset discharging current value;

[0018] Furthermore, the second charging parameter D2 is used to perform several rounds of second charging operations on the current lithium battery, including:

[0019] The current lithium battery is subjected to several rounds of second charging operations using a target charging voltage value determined based on the first preset voltage U1 and the preset voltage increase value. Each round of second charging operations includes charging the current lithium battery to the second preset voltage U2, wherein the first preset voltage U1 and the target charging voltage value are both within the preset voltage range.

[0020] Preferably, it also includes:

[0021] If the target charging voltage value determined based on the first preset voltage U1 and the preset voltage increase value is greater than the upper limit value within the preset voltage range, the upper limit value is determined as the target charging voltage value.

[0022] Preferably, it also includes:

[0023] If the first preset voltage U1 is not equal to the second preset voltage U2, the first charging parameter D1 is configured as a constant second preset charging current value, the second charging parameter D2 is configured as a constant third preset charging current value, and the preset discharge parameter D3 is configured as a constant preset discharge current value; wherein the second preset charging current value, the third preset charging current value, and the preset discharge current value are all equal.

[0024] Preferably, before determining whether the current operating voltage of the lithium battery is less than the preset operating voltage U of the lithium battery, the method further includes:

[0025] Determine whether the lithium battery has undergone a preset number of charge and discharge cycles;

[0026] If so, the step of determining whether the current operating voltage of the lithium battery is less than the preset operating voltage U of the lithium battery is triggered.

[0027] Preferably, the preset temperature range is 20°C-55°C.

[0028] In order to solve the above problems, the present application also provides a lithium-rich manganese-based positive electrode working voltage recovery system, comprising:

[0029] A judgment module, used to judge whether the current working voltage of the lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than the preset working voltage U of the lithium battery, and if so, to stand for a first time t1 after the current lithium battery is discharged;

[0030] A determination module, used to determine a first preset voltage U1, a second preset voltage U2 and a third preset voltage U3;

[0031] A first operating module, used to perform several rounds of first charging operations on the current lithium battery using a first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to a first preset voltage U1 and standing for a second time t2;

[0032] A second operation module, used to determine a second charging parameter D2 based on a judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and perform several rounds of second charging operations on the current lithium battery using the second charging parameter D2; each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3;

[0033] The third operation module is used to discharge the current lithium battery to a third preset voltage U3 using a preset discharge parameter D3, and stand for a fourth time t4, and then detect the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored.

[0034] To solve the above problems, the present application also provides an electronic device, including a memory for storing a computer program;

[0035] A processor is used to implement the steps of the above-mentioned method for restoring the working voltage of the lithium-rich manganese-based positive electrode when executing a computer program.

[0036] To solve the above problems, the present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned lithium-rich manganese-based positive electrode working voltage recovery method are implemented.

[0037] The present application provides a method for recovering the working voltage of a lithium-rich manganese-based positive electrode, comprising: determining whether the current working voltage of a lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than a preset working voltage U of the lithium battery, and if so, standing for a first time t1 after the current lithium battery is discharged; determining a first preset voltage U1, a second preset voltage U2, and a third preset voltage U3; performing several rounds of first charging operations on the current lithium battery using a first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to the first preset voltage U1 and standing for a second time t2; determining a second charging parameter D2 based on a judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and performing several rounds of second charging operations on the current lithium battery using the second charging parameter D2; each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3; discharging the current lithium battery to the third preset voltage U3 using a preset discharge parameter D3 and standing for a fourth time t4, and then detecting the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored. The method provided in the present application can restore the structure of the lithium-rich manganese-based positive electrode material in the lithium battery that has been damaged after a long cycle, thereby restoring the working voltage of the lithium-rich manganese-based positive electrode, that is, increasing the working voltage of the lithium battery corresponding to the lithium-rich manganese-based positive electrode. The present application has simple steps and is easy to operate. It can be implemented in a battery management system, which is conducive to the commercial use of lithium-rich manganese-based lithium batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0039] Figure 1 A flow chart of a method for restoring the working voltage of a lithium-rich manganese-based positive electrode provided in an embodiment of the present application;

[0040] Figure 2 A diagram showing changes in unit cell parameters in a lithium-rich manganese-based positive electrode material provided in an embodiment of the present application;

[0041] Figure 3 The process flow provided for the embodiments of the present application;

[0042] Figure 4 A comparison chart of the button-type battery operating voltage restored by the constant voltage method provided in the embodiment of the present application and the button-type battery operating voltage in Comparative Example 1;

[0043] Figure 5 A schematic diagram of restoring the working voltage of a soft-pack battery using a constant voltage method provided in an embodiment of the present application;

[0044] Figure 6 A comparison chart of the working voltage of a soft-pack battery restored by a constant current method provided in an embodiment of the present application and the working voltage of a soft-pack battery in Comparative Example 2;

[0045] Figure 7 A schematic diagram of restoring the working voltage of a button cell using a constant current method provided in an embodiment of the present application;

[0046] Figure 8 An overall flow chart of a method for restoring the working voltage of a lithium-rich manganese-based positive electrode provided in an embodiment of the present application;

[0047] Fig. 9 A module diagram of a lithium-rich manganese-based positive electrode working voltage recovery system provided in an embodiment of the present application;

[0048] Fig.10 A structural diagram of an electronic device provided in another embodiment of the present application. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0050] The core of this application is to provide a method, system, equipment and medium for recovering the working voltage of a lithium-rich manganese-based positive electrode.

[0051] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0052] As energy issues are increasingly valued, energy revolutions have been launched in all walks of life. In the field of transportation, the new energy vehicle industry is also undergoing high-quality development. Despite this, the often-mentioned "mileage anxiety" problem is still a technical barrier that prevents consumers from choosing electric vehicles. The endurance of electric vehicles depends on the energy density of power batteries. Among them, the capacity of the positive electrode material is a key part of determining the energy density of power lithium batteries, and the energy density that traditional layered materials can provide is close to the limit. Since its discovery, lithium-rich manganese-based positive electrode materials have attracted much attention from researchers. This is because they have an ultra-high discharge specific capacity (>250mAh / g), which can theoretically achieve the construction of 500Wh / kg high energy density batteries. This feature makes lithium-rich manganese-based materials gradually become an ideal choice for positive electrode materials for power batteries.

[0053] It is generally believed that there is a two-phase structure in lithium-rich manganese-based positive electrode materials, that is, the lithium-rich phase of Li2MnO3 is dispersed in the traditional layered structure LiTMO2 layered phase. Because of this, lithium-rich manganese-based positive electrode materials also have a unique energy storage mechanism. During the first charging process, when the charging voltage is below 4.45V, Li + Ni in the LiTMO2 layered phase is released from the positive electrode material 2+ 、Co 3+ The ions are oxidized to Ni 3+ and Co 4+ This process is the same as that of traditional layered oxide positive electrode materials; when the charging voltage exceeds 4.45V, the lithium-rich phase of Li2MnO3 is activated, and the lattice oxygen is oxidized to generate O2, which is Li + The continued release of Li provides charge compensation. After the first cycle of charge and discharge, due to the loss of lattice oxygen, the released Li + It is impossible to completely embed back into the structure, resulting in a large loss of discharge capacity in the first cycle. At the same time, as the cycle progresses, the discharge voltage of the lithium-rich manganese-based positive electrode material continues to decrease, which in turn causes a decrease in the energy density of the constructed battery. Therefore, developing an effective method to solve the voltage decay problem is a necessary means to promote the application of lithium-rich manganese-based positive electrode materials in the field of power lithium batteries.

[0054] The explanation for the voltage decay of lithium-rich manganese-based cathode materials is mainly that the migration of transition metal ions during the cycle causes an irreversible phase transition. However, the root cause of this phase change is the activation of lattice oxygen. At present, the solution to voltage decay often focuses too much on transition metal ions, lacking effective measures directly targeting lattice oxygen. In addition, the doping and coating methods proposed today will have a certain degree of influence on the redox of lattice oxygen in lithium-rich manganese-based cathode materials, inevitably damaging the ultra-high capacity of lithium-rich manganese-based cathode materials. In the final analysis, the working voltage of the electrode material is closely related to its own structure. The voltage decay of lithium-rich manganese-based cathode materials indicates that its own crystal structure has degraded. At present, some research has been conducted on the recovery of the working voltage of lithium-rich manganese-based cathode materials by adjusting the crystal structure. For example, the lithium-rich manganese-based cathode material after cycling is heated at an appropriate temperature to return the lattice oxygen framework that was originally in a metastable state to a steady state, the overall structure is restored, and its discharge voltage is restored accordingly. However, this method involves high-temperature treatment, which causes serious damage to battery components such as electrolytes and diaphragms, and cannot be implemented in a battery system.

[0055] Therefore, it is necessary to study a new idea and simple solution for lattice oxygen framework recovery, so that the degraded crystal structure of lithium-rich manganese-based positive electrode materials can return to a steady state after long cycles, and then restore the attenuated discharge voltage of lithium-rich manganese-based lithium batteries, so as to cope with the shortcomings of current technology and solve or alleviate the problems caused by voltage attenuation.

[0056] Therefore, the present application provides a method for recovering the working voltage of a lithium-rich manganese-based positive electrode to solve the above problems. Figure 1 A flow chart of a method for restoring the working voltage of a lithium-rich manganese-based positive electrode provided in an embodiment of the present application, as shown in the figure, includes the following process:

[0057] S10: Determine whether the current operating voltage of the lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than the preset operating voltage U of the lithium battery. If so, let the current lithium battery stand for a first time t1 after the discharge is completed.

[0058] In a specific embodiment, after a lithium battery has been used for a period of time, it will be worn out, and the internal chemical structure of the lithium battery, that is, the lithium-rich manganese-based positive electrode material will change, and the operating voltage will decrease. After the lithium battery has worked for a period of time, it is determined whether the current operating voltage of the lithium battery is less than the original preset operating voltage U of the lithium battery. If it is less than, it means that the chemical structure inside the lithium battery has changed. At this time, the lithium battery is discharged and left to stand for a first time t1 after discharge to allow the lithium battery to be in a stable state.

[0059] Among them, the current working voltage needs to be detected. The preset working voltage U is related to the model, manufacturer, and size of the battery. The first static time t1 is also related to the temperature and state. This application is not limited and can be set according to actual conditions.

[0060] S11: Determine a first preset voltage U1, a second preset voltage U2, and a third preset voltage U3.

[0061] In a specific embodiment, the chemical structure in the lithium battery changes differently according to different currents and voltages. The present application determines three voltages, namely, a first preset voltage U1, a second preset voltage U2, and a third preset voltage U3, according to the corresponding relationship between the required changes and the voltages.

[0062] Among them, as a preference, the first preset voltage U1 is any value between 3.2V and 4.4V (relative to lithium potential), the second preset voltage U2 is any value between 3.4V and 4.4V (relative to lithium potential), and the third preset voltage U3 is any value between 2.0V and 3.0V (relative to lithium potential).

[0063] S12: performing several rounds of first charging operations on the current lithium battery using the first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to a first preset voltage U1 and standing for a second time t2.

[0064] In a specific embodiment, the first charging parameter D1 is used to perform several rounds of first charging operations on the current lithium battery within a preset temperature range, wherein each round of the first charging operation charges the current lithium battery to a first preset voltage U1, and leaves it to rest for a second time t2. The preset temperature is an optimal environment. After all, the efficiency of battery charging and discharging and the internal chemical structure are all related to the temperature. The preset temperature in the embodiment of the present application is only a preferred method to reduce resource waste and detection time, which can be 20°C to 55°C. The first charging parameter D1 is used to charge the current lithium battery, charge the current lithium battery to a first preset voltage U1, and leave it to rest for a second time t2, in order to cause the chemical structure of the lithium battery to undergo the first change and be in a stable state. The purpose of performing several rounds of the first charging operation on the current lithium battery is that it is impossible to guarantee a single recovery process, and the working voltage of the lithium battery will return to the state of the preset working voltage, so several rounds of overall recovery operations are required.

[0065] It should be noted that the first charging parameter D1 can be a voltage parameter or a current parameter, which is not limited in this application. At the same time, the second preset time t2 can be 2 to 5 minutes, which is not limited in this application and can be set according to user needs.

[0066] S13: Determine the second charging parameter D2 based on the judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and use the second charging parameter D2 to perform several rounds of second charging operations on the current lithium battery; each round of second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3.

[0067] In a specific embodiment, the second charging parameter D2 is determined according to the result of judging whether the first preset voltage U1 and the second preset voltage U2 are equal, that is, the second charging parameter D2 includes two different charging parameters, and the corresponding charging parameter is determined according to whether they are equal at present, and the current lithium battery is subjected to several rounds of second charging operation according to the currently determined second charging parameter D2; each round of second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3; the purpose is to make the chemical structure of the lithium battery undergo a second change and be in a stable state. Among them, the purpose of several rounds is that the working voltage of the lithium battery cannot be guaranteed to be restored to the state of the preset working voltage U in one recovery process, so several rounds of overall recovery operation are required.

[0068] It should be noted that the second charging parameter D2 can be a voltage parameter or a current parameter, which is not limited in this application. At the same time, the third preset time is not limited in this application and can be set according to the needs of the user.

[0069] S14: Discharge the current lithium battery to a third preset voltage U3 using a preset discharge parameter D3, and leave it alone for a fourth time t4, and then detect the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored.

[0070] In a specific embodiment, the lithium battery performs normal discharge operation through the preset discharge parameter D3, and stands still for a fourth time t4. After the lithium battery is fully discharged and in a stable state, the current working voltage of the current lithium battery is detected to determine whether the working voltage of the lithium-rich manganese-based positive electrode, that is, the lithium battery, has recovered to the value of the preset working voltage U.

[0071] As a preferred embodiment, the preset discharge parameter D3 is a current parameter, which is any value in the range of 0.01C to 10C. Then, the third preset voltage U3 is any value in the range of 2.0V to 3.0V (relative to lithium potential), and the standing time is 2 to 5 minutes.

[0072] The lithium battery used in this application is preferably a lithium-rich manganese-based lithium battery, which is characterized by comprising a positive electrode, a negative electrode, a separator and an electrolyte, and the positive electrode material of the lithium-rich manganese-based lithium battery contains a lithium-rich manganese-based positive electrode material. The chemical formula of the lithium-rich manganese-based positive electrode material is Li 1+α Ni x Coy Mn z M d O2; wherein 0<α≤0.2, 0.1<x<0.5, 0≤y<0.3, 0.5≤z<0.9, 0≤d≤0.5, wherein M is one or more of iron, aluminum, vanadium, zirconium, titanium, tin, magnesium, molybdenum and niobium. The negative electrode material comprises one or more of lithium metal negative electrode, graphite negative electrode, silicon carbon negative electrode, lithium carbon negative electrode and other negative electrode materials for lithium ion batteries. The diaphragm is selected from the Celgard series. The electrolyte is selected to be 1mol / L, and LiPF6 is in EC:DMC=3:7.

[0073] The principle of the method of the present application is to use an electrochemical method to restore the disordered structure of the lithium-rich manganese-based positive electrode material after cycling, thereby restoring its operating voltage. Figure 2 The present invention provides the changes in the unit cell parameters obtained by refining the unit cell parameters of the lithium-rich manganese-based positive electrode material through GSAS and other related crystal structure refinement software. When the original material is charged and discharged for one cycle in the high voltage range (>4.5V, relative to lithium potential), the unit cell parameters (a, c) both increase; when the recovery working voltage provided by the present application is used, it can be seen that the unit cell parameters (a, c) both decrease with the increase in the number of cycles, indicating that the present application can achieve structural recovery of the lithium-rich manganese-based positive electrode material after cycling.

[0074] The present application provides a method for recovering the working voltage of a lithium-rich manganese-based positive electrode, comprising: determining whether the current working voltage of a lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than a preset working voltage U of the lithium battery, and if so, standing for a first time t1 after the current lithium battery is discharged; determining a first preset voltage U1, a second preset voltage U2, and a third preset voltage U3; performing several rounds of first charging operations on the current lithium battery using a first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to the first preset voltage U1 and standing for a second time t2; determining a second charging parameter D2 based on a judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and performing several rounds of second charging operations on the current lithium battery using the second charging parameter D2; each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3; discharging the current lithium battery to the third preset voltage U3 using a preset discharge parameter D3 and standing for a fourth time t4, and then detecting the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored. The method provided in this application can restore the damaged structure of the lithium-rich manganese-based positive electrode material in the lithium battery after a long cycle, thereby restoring the working voltage of the lithium-rich manganese-based positive electrode, that is, increasing the working voltage of the lithium battery. The application has simple steps and is easy to operate. It can be implemented in a battery management system, which is conducive to the commercial use of lithium-rich manganese-based lithium batteries.

[0075] Based on the above embodiment, as a preferred embodiment, detecting the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored includes:

[0076] Detect the current working voltage of the current lithium battery to determine the current voltage recovery value;

[0077] If the current voltage recovery value is less than the preset percentage value of the loss voltage, it is determined that the working voltage of the lithium-rich manganese-based positive electrode has not been recovered, and the process jumps again to the step of performing several rounds of first charging operations on the current lithium battery using the first charging parameter D1 at the preset temperature;

[0078] When the current voltage recovery value is not less than a preset percentage value of the loss voltage, it is determined that the working voltage of the lithium-rich manganese-based positive electrode has been restored.

[0079] In a specific embodiment, the stabilized lithium battery is tested and a voltage recovery value after the test is obtained. If the recovery value is less than a preset percentage value of the loss voltage, it is determined that the working voltage of the currently tested lithium-rich manganese-based positive electrode has not been recovered, and it is necessary to restart the voltage recovery process, that is, jump again to the step of performing several rounds of first charging operations on the current lithium battery using the first charging parameter D1 at a preset temperature. If the current voltage recovery value is not less than a preset percentage value of the loss voltage, it is determined that the working voltage of the lithium-rich manganese-based positive electrode has been recovered, and the lithium battery corresponding to the lithium-rich manganese-based positive electrode starts to work normally.

[0080] Among them, the preset percentage can be 50% as the most preferred one, the loss voltage is the difference between the preset working voltage U and the detected working voltage, and the voltage recovery value is the difference between the lithium battery working voltage detected after a voltage recovery process and the lithium battery working voltage detected initially.

[0081] The embodiment of the present application detects the voltage of the lithium battery after the recovery process to determine whether it meets the requirements, thereby further improving the working voltage recovery process of the lithium battery.

[0082] Based on the above embodiment, as a preferred embodiment, it also includes:

[0083] If the first preset voltage U1 is equal to the second preset voltage U2, the first charging parameter D1 is configured as a constant first preset charging current value and the preset discharging parameter D3 is configured as a constant first preset discharging current value;

[0084] Furthermore, the second charging parameter D2 is used to perform several rounds of second charging operations on the current lithium battery, including:

[0085] The current lithium battery is subjected to several rounds of second charging operations using a target charging voltage value determined based on the first preset voltage U1 and the preset voltage increase value. Each round of second charging operations includes charging the current lithium battery to the second preset voltage U2, wherein the first preset voltage U1 and the target charging voltage value are both within the preset voltage range.

[0086] If the target charging voltage value determined based on the first preset voltage U1 and the preset voltage increase value is greater than the upper limit value within the preset voltage range, the upper limit value is determined as the target charging voltage value.

[0087] In a specific embodiment, Figure 3 As shown on the left, D1 is the first charging parameter, I1 is the first preset charging current value, D2 is the second charging parameter, I2 is the voltage or current parameter corresponding to the second charging parameter in the current state, D3 is the preset discharge parameter, I3 is the preset discharge current value, U1 is the first preset voltage, U2 is the second preset voltage, and U3 is the third preset voltage. If the first preset voltage U1 is equal to the second preset voltage U2, the method for restoring the voltage of the lithium battery is called the constant voltage method. At this time, the first charging parameter D1 is the first preset charging current value I1, and the preset discharge parameter D3 is the constant preset discharge current value I3. At this time, the voltage of the lithium battery is at the first preset voltage U1. At the same time, the second charging parameter D2 is used to perform several rounds of second charging operations on the current lithium battery, including using the target charging voltage value determined based on the first preset voltage U1 and the preset voltage increase value to perform several rounds of second charging operations on the current lithium battery. Each round of second charging operation includes charging the current lithium battery to the second preset voltage U2, wherein the first preset voltage U1 and the target charging voltage value are both within the preset voltage range.

[0088] For example: during the first round of the second charging operation, the first preset voltage U1 (that is, the second preset voltage U2) is used to charge the lithium battery; during the second round of the second operation, the first preset voltage U1+the preset voltage determination value is used to charge the lithium battery; during the third round of the second charging operation, the first preset voltage U1+the two preset voltage determination values ​​are used to charge the lithium battery, that is to say: the voltage of each round of the second charging operation is increased by a preset voltage determination value compared with the voltage of the previous round of the second charging operation.

[0089] Among them, as a preferred embodiment, the first preset voltage U1 and the second preset voltage U2 can be any value between 3.2V and 4.4V, the preset voltage determination value is 0.1V, the corresponding third time t3 is preferably 10 to 240 hours, and the first preset charging current value I1 is 0.01C to 10C.

[0090] Among them, it should be emphasized that if the target charging voltage value determined based on the first preset voltage U1 and the preset voltage increase value is greater than the upper limit value within the preset voltage range, the upper limit value is determined as the target charging voltage value, that is, the target charging voltage value determined by the first preset voltage U1 and the preset voltage increase value must meet the requirements within the preset voltage range. If it is greater than the upper limit value within the preset voltage range, the upper limit value is determined as the target charging voltage value so that the second charging operation can be charged through the upper limit value.

[0091] Among them, as a preferred embodiment, the preset voltage range is 3.0~4.0V.

[0092] The present application determines the type of the corresponding second charging parameter and the cycle process of the second charging parameter through the magnitude relationship between the first preset voltage U1 and the second preset voltage U2.

[0093] Based on the above embodiment, as a preferred embodiment, it also includes:

[0094] If the first preset voltage U1 is not equal to the second preset voltage U2, the first charging parameter D1 is configured as a constant second preset charging current value, the second charging parameter D2 is configured as a constant third preset charging current value, and the preset discharge parameter D3 is configured as a constant preset discharge current value; wherein the second preset charging current value, the third preset charging current value, and the preset discharge current value are all equal.

[0095] In a specific embodiment, Figure 3 As shown on the right, D1 is the first charging parameter, I1 is the second preset charging current value, D2 is the second charging parameter, I2 is the third preset charging current value, D3 is the preset discharge parameter, I3 is the preset discharge current value, U1 is the first preset voltage, U2 is the second preset voltage, and U3 is the third preset voltage. If the first preset voltage U1 is not equal to the second preset voltage U2, the lithium battery voltage recovery method is changed to a constant current method, at which time the first charging parameter D1 is configured as a constant second preset charging current value I1, the second charging parameter D2 is configured as a constant third preset charging current value I2, and the preset discharge parameter D3 is configured as a constant preset discharge current value I3; wherein the second preset charging current value I1, the third preset charging current value I2, and the preset discharge current value I3 are all equal.

[0096] Among them, as a preference, the second preset charging current value I1 is 0.01C~10C, the third preset charging current I2 is 0.01C~10C, and the corresponding static stabilization time is 2~5min. The embodiment of the present application is only one way that can be implemented, but it is not limited to only this way, and can be set according to the needs of the user.

[0097] Based on the above embodiment, as a preferred embodiment, before determining whether the current operating voltage of the lithium battery is less than the preset operating voltage of the lithium battery, the method further includes:

[0098] Determine whether the lithium battery has undergone a preset number of charge and discharge cycles;

[0099] If so, the step of determining whether the current operating voltage of the lithium battery is less than the preset operating voltage U of the lithium battery is triggered.

[0100] In a specific embodiment, as a preference, after the lithium battery performs a preset number of charge and discharge cycles, the relationship between the current operating voltage of the lithium battery and the preset operating voltage U is determined, thereby reducing waste of resources.

[0101] Among them, as a preferred embodiment, the preset number of cycles is 500 times.

[0102] Lithium-rich manganese-based lithium batteries can be divided into button cells and soft-pack batteries, wherein both button cells and soft-pack batteries can adopt the constant current method and constant voltage method in the above embodiments.

[0103] The steps of constructing the battery system of the button battery include: selecting lithium-rich manganese-based positive electrode material Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O2 was prepared with conductive carbon black and polyvinylidene fluoride in a mass ratio of 8:1:1, dispersed in N-methylpyrrolidone to form a uniform slurry, and evenly coated on the surface of aluminum foil to obtain a button battery electrode. The coating thickness was 300 μm and the single-sided active material loading was 5 mg / cm 2 ; 100μm thick metallic lithium was selected as the negative electrode material; 1 mol / L LiPF6 ethylene carbonate (EC) and dimethyl carbonate (DMC) solution was selected as the electrolyte, in which the volume ratio of EC to DMC was 1:1; a 16μm thick diaphragm was selected; and button cells were assembled in a glove box filled with argon.

[0104] The steps of constructing the battery system of the soft pack battery include: selecting lithium-rich manganese-based material Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O2 was used as the positive electrode material. It was prepared with conductive carbon black and polyvinylidene fluoride in a mass ratio of 8:1:1, dispersed in N-methylpyrrolidone to form a uniform slurry, and evenly coated on both sides of the aluminum foil to obtain the positive electrode sheet of the soft-pack battery. The active material loading on one side was 10 mg / cm 2 , cold pressed density is 2.2mg / cm 3The size of the pole piece is 72mm×62mm, and the length of the pole piece and the pole ear is 30mm; G49 graphite is selected as the negative electrode material, and it is mixed with conductive carbon black and SBR / CMC binder in a certain proportion to form a uniform slurry, which is evenly coated on the double-sided copper foil soft-pack battery negative electrode piece, the pole piece size is 74mm×64mm, and the length of the pole piece and the pole ear is 20mm; 1mol / L LiPF6 ethylene carbonate (EC) and dimethyl carbonate (DMC) solution are selected as the electrolyte, in which the volume ratio of EC to DMC is 1:1; a diaphragm with a thickness of 16μm is selected; aluminum pole ears and copper-plated nickel pole ears are selected as the external pole ears of the positive and negative electrodes of the soft-pack battery; an aluminum-plastic film with a thickness of 113μm is selected as the outer skin of the soft-pack battery; 1Ah soft-pack batteries are assembled in a clean room.

[0105] Among them, in comparative example 1, the assembly process used by the lithium-rich manganese-based lithium battery button cell is consistent with the above construction process, and the charge and discharge cycle is carried out in the voltage range of 2.0-4.8V at a constant current of 0.1C. Comparative example 2: The assembly process used by the 1Ah lithium-rich manganese-based lithium battery soft pack battery is consistent with the above construction process, and the charge and discharge cycle is carried out in the voltage range of 2.0-4.55V at a constant current of 0.1C.

[0106] In summary, the constant voltage method is used to restore the working voltage of the button battery, which is specifically implemented as follows:

[0107] 1. The assembled lithium-rich manganese-based lithium button cell was tested for charge and discharge cycle performance using an electrochemical testing instrument. The button cell was left to stand for 12 hours before the test. The test temperature was 25°C, the charge cut-off voltage was 4.8V (relative to lithium potential), the discharge cut-off voltage was 2.0V (relative to lithium potential), and constant current charge and discharge cycles were performed at a rate current of 0.1C to obtain battery A.

[0108] 2. After 5 cycles, the operating voltage of the monitored battery A is lower than the preset operating voltage setting value, and it is determined that the voltage of the battery A needs to be restored.

[0109] 3. Battery A was charged to 3.6V at a constant current rate of 0.1C and allowed to stand for 3 minutes to obtain battery B.

[0110] 4. Then, battery B was charged at a constant voltage of 3.6 V for 96 hours to obtain battery C.

[0111] 5. Battery C was discharged at a constant current rate of 0.1C to 2V. Battery C was left standing for 3 minutes to obtain Battery D.

[0112] 6. It is determined whether the battery D has only recovered less than 50% of the lost working voltage value, which is less than the preset value, and further voltage recovery operation is required.

[0113] 7. Repeat steps 3 to 6 until the operating voltage of battery D returns to the preset operating voltage value, wherein the constant voltage charging voltage increases by 0.1V each time within the range of 3.0V to 4.0V.

[0114] 8. Cycle performance test: The lithium-ion battery D is charged and discharged at a constant current rate of 0.1C, with a charge cut-off voltage of 4.8V and a discharge cut-off voltage of 2V.

[0115] The method is used to restore the working voltage of the lithium-rich manganese-based lithium battery button cell. The comparison with the working voltage of the button cell in Comparative Example 1 is shown in Figure 4 .

[0116] Correspondingly, based on the above embodiments, the constant voltage method is used to restore the working voltage of the soft-pack battery, which is specifically implemented as follows:

[0117] 1. The charge and discharge cycle performance of the above-assembled lithium-rich manganese-based lithium battery was tested using an electrochemical testing instrument. The soft-pack battery needed to be left to stand for 12 hours before the test. The test temperature was 25°C, the charge cut-off voltage was 4.55V (relative to lithium potential), the discharge cut-off voltage was 2.0V (relative to lithium potential), and constant current charge and discharge cycles were performed at a rate current of 0.1C to obtain battery A.

[0118] 2. After 5 cycles, the working voltage of the monitored battery A is lower than the preset working voltage setting value, and it is determined that the voltage of battery A needs to be restored.

[0119] 3. Battery A was charged to 4.2V at a constant current rate of 0.1C and allowed to stand for 3 minutes to obtain battery B.

[0120] 4. Then, battery B was charged at a constant voltage of 4.2 V for 96 hours to obtain battery C.

[0121] 5. After leaving battery C to stand for 3 minutes, discharge battery C at a constant current of 0.1C to 2V to obtain battery D.

[0122] 6. It is found that battery D has only recovered less than 50% of the lost working voltage value, which is less than the preset value, and further voltage recovery operation is required.

[0123] 7. Cycle performance test: The lithium-ion battery D is charged and discharged at a constant current rate of 0.1C, with a charge cut-off voltage of 4.55V and a discharge cut-off voltage of 2V. The operating voltage of the lithium-rich manganese-based lithium battery after voltage recovery operation is as follows: Figure 5 shown.

[0124] In summary, the constant current method is used to restore the working voltage of the soft-pack battery, which is specifically implemented as follows:

[0125] 1. The charge and discharge cycle performance of the above-assembled lithium-rich manganese-based lithium battery was tested using an electrochemical testing instrument. The soft-pack battery needed to be left to stand for 12 hours before the test. The test temperature was 25°C, the charge cut-off voltage was 4.55V (relative to lithium potential), the discharge cut-off voltage was 2.0V (relative to lithium potential), and constant current charge and discharge cycles were performed at a rate current of 0.1C to obtain battery A.

[0126] 2. After 50 cycles, the operating voltage of the monitored battery A is lower than the set value of the preset operating voltage, and it is determined that the voltage of the battery A needs to be restored.

[0127] 3. Using the constant current charging method, charge battery A to 4.15V (relative to lithium potential) at a rate current of 0.1C, let it stand for 3 minutes, and obtain battery B.

[0128] 4. Using the constant current discharge method, discharge battery B at a rate current of 0.1C to 2.0V (relative to lithium potential), let it stand for 3 minutes, and obtain battery C.

[0129] 5. It is found that the battery C has only recovered less than 50% of the lost working voltage value, which is less than the preset value, and further voltage recovery operation is required.

[0130] 6. Repeat steps 2 to 5 for a total of 50 times until the operating voltage of battery C returns to the preset operating voltage value.

[0131] 7. Cycle performance test: The lithium-ion battery D is charged and discharged at a constant current rate of 0.1C for 50 cycles. The charge cut-off voltage is 4.55V and the discharge cut-off voltage is 2V.

[0132] The method is used to restore the working voltage of the lithium-rich manganese-based lithium battery soft pack battery, and the comparison with the working voltage of the soft pack battery in Comparative Example 2 is shown in Figure 6 .

[0133] Correspondingly, based on the above embodiments, the constant current method is used to restore the working voltage of the button battery, which is specifically implemented as follows:

[0134] 1. The charge and discharge cycle performance of the above-assembled lithium-rich manganese-based lithium battery was tested using an electrochemical testing instrument. The button cell was left to stand for 12 hours before the test. The test temperature was 25°C, the charge cut-off voltage was 4.8V (relative to lithium potential), the discharge cut-off voltage was 2.0V (relative to lithium potential), and constant current charge and discharge cycles were performed at a rate current of 0.2C to obtain battery A.

[0135] 2. After 50 cycles, the operating voltage of the monitored battery A is lower than the set value of the preset operating voltage, and it is determined that the voltage of the battery A needs to be restored.

[0136] 3. Using the constant current charging method, charge battery A at a rate current of 0.2C to 3.95V (relative to lithium potential), let it stand for 3 minutes, and obtain battery B.

[0137] 4. Using the constant current discharge method, discharge battery B at a rate current of 0.2C to 2.0V (relative to lithium potential), let it stand for 3 minutes, and obtain battery C.

[0138] 5. It is found that the battery C has only recovered less than 50% of the lost working voltage value, which is less than the preset value, and further voltage recovery operation is required.

[0139] 6. Repeat steps 2 to 5 for a total of 50 times until the operating voltage of battery C returns to the preset operating voltage value.

[0140] 7. Cycle performance test: The lithium-ion battery D was charged and discharged at a constant current rate of 0.2C for 50 cycles, with a charge cut-off voltage of 4.8V and a discharge cut-off voltage of 2V. The working voltage of the lithium-rich manganese-based lithium battery after voltage recovery operation is as follows: Figure 7 shown.

[0141] It should be noted that the specific values ​​of voltage, temperature, current, etc. provided in the above embodiments are all achievable embodiments, but the present application is not limited to only this embodiment and can be set according to the needs of the user.

[0142] The present application provides a method for recovering the working voltage of a lithium-rich manganese-based positive electrode, comprising: determining whether the current working voltage of a lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than a preset working voltage U of the lithium battery, and if so, standing for a first time t1 after the current lithium battery is discharged; determining a first preset voltage U1, a second preset voltage U2, and a third preset voltage U3; performing several rounds of first charging operations on the current lithium battery using a first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to the first preset voltage U1 and standing for a second time t2; determining a second charging parameter D2 based on a judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and performing several rounds of second charging operations on the current lithium battery using the second charging parameter D2; each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3; discharging the current lithium battery to the third preset voltage U3 using a preset discharge parameter D3, and standing for a fourth time t4, and then detecting the current working voltage of the current lithium battery to determine whether the working voltage of the lithium battery has been restored. According to the relationship between the first preset voltage U1 and the second preset voltage U2, this application determines two methods for restoring the working voltage of the lithium-rich manganese-based positive electrode, the constant voltage method and the constant current method. Both the constant voltage method and the constant current method can restore the structure of the lithium-rich manganese-based positive electrode material in the lithium battery that has been damaged after a long cycle, thereby restoring the working voltage of the lithium-rich manganese-based positive electrode, that is, increasing the working voltage of the lithium battery. Among them, the steps of this application are simple and easy to operate. It can be implemented in the battery management system, which is conducive to the commercial use of lithium-rich manganese-based lithium batteries.

[0143] At the same time, based on the above embodiments, the overall flow chart of a method for restoring the working voltage of a lithium-rich manganese-based positive electrode provided in the embodiment of the present application is as follows: Figure 8 As shown, the following process is included:

[0144] After the battery is finished working, it is determined whether the voltage needs to be restored. If so, there are two methods, the constant voltage method and the constant current method. If not, the battery works; the constant voltage method first requires constant current charging (that is, the first charging parameter D1 charging in the text), and then requires constant voltage charging (that is, the second charging parameter D2 charging in the text), and then requires constant current discharge (that is, preset discharge parameter D3 discharge), and performs a charge and discharge cycle. Finally, it is necessary to determine whether the voltage is restored. If it is restored, the battery works. If it is not restored, it returns to the selection step of the constant voltage method or the constant current method; the constant current method first requires constant current charging (that is, the first charging parameter D1 in the text), and then requires constant current charging (that is, the second charging parameter charging D2 in the text), and then requires constant current discharge (that is, preset discharge parameter discharge D3), and performs a charge and discharge cycle. Finally, it is necessary to determine whether the voltage is restored. If it is restored, the battery works. If it is not restored, it returns to the selection step of the constant voltage method or the constant current method.

[0145] In the above embodiments, the method for recovering the working voltage of a lithium-rich manganese-based positive electrode is described in detail, and the present application also provides an embodiment corresponding to a device for recovering the working voltage of a lithium-rich manganese-based positive electrode. It should be noted that the present application describes the embodiments of the device part from two perspectives, one is based on the perspective of functional modules, and the other is based on the perspective of hardware.

[0146] Fig. 9 A module diagram of a lithium-rich manganese-based positive electrode working voltage recovery system provided in an embodiment of the present application includes:

[0147] A judgment module 11 is used to judge whether the current working voltage of the lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than a preset working voltage U of the lithium battery, and if so, the lithium battery is left standing for a first time t1 after the current lithium battery is discharged;

[0148] A determination module 12, used to determine a first preset voltage U1, a second preset voltage U2 and a third preset voltage U3;

[0149] A first operating module 13, configured to perform several rounds of first charging operations on the current lithium battery using a first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to a first preset voltage U1 and standing for a second time t2;

[0150] The second operation module 14 is used to determine the second charging parameter D2 based on the judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and perform several rounds of second charging operations on the current lithium battery using the second charging parameter D2; each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3;

[0151] The third operating module 15 is used to discharge the current lithium battery to a third preset voltage U3 using a preset discharge parameter D3, and stand for a fourth time t4, and then detect the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored.

[0152] Since the embodiments of the apparatus part correspond to the embodiments of the method part, please refer to the description of the embodiments of the method part for the embodiments of the apparatus part, which will not be repeated here.

[0153] Fig.10 A structural diagram of an electronic device provided in another embodiment of the present application, such as Fig.10 As shown, the electronic device includes: a memory 20 for storing a computer program;

[0154] The processor 21 is used to implement the steps of the method for restoring the working voltage of the lithium-rich manganese-based positive electrode mentioned in the above embodiment when executing the computer program.

[0155] The electronic device provided in this embodiment may include but is not limited to a smart phone, a tablet computer, a laptop computer or a desktop computer.

[0156] Among them, the processor 21 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 21 can be implemented in at least one hardware form of a digital signal processor (DSP), a field-programmable gate array (FPGA), and a programmable logic array (PLA). The processor 21 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a central processing unit (CPU); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 21 may be integrated with a graphics processing unit (GPU), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 21 may also include an artificial intelligence (AI) processor, which is used to process computing operations related to machine learning.

[0157] The memory 20 may include one or more computer-readable storage media, which may be non-transitory. The memory 20 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In this embodiment, the memory 20 is at least used to store the following computer program 201, wherein the computer program is loaded and executed by the processor 21, and the steps related to the recovery of the working voltage of the lithium-rich manganese-based positive electrode disclosed in any of the aforementioned embodiments can be implemented. In addition, the resources stored in the memory 20 may also include an operating system 202 and data 203, etc., and the storage method may be short-term storage or permanent storage. Among them, the operating system 202 may include Windows, Unix, Linux, etc.

[0158] In some embodiments, the electronic device may further include a display screen 22 , an input / output interface 23 , a communication interface 24 , a power source 25 , and a communication bus 26 .

[0159] Those skilled in the art will understand that Fig.10 The structure shown in the figure does not constitute a limitation on the electronic device, and may include more or fewer components than shown in the figure.

[0160] The electronic device provided in the embodiment of the present application includes a memory and a processor. When the processor executes the program stored in the memory, it can implement the following method: a method for recovering the working voltage of a lithium-rich manganese-based positive electrode.

[0161] Finally, the present application also provides an embodiment corresponding to a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps recorded in the above method embodiment are implemented.

[0162] It is understandable that if the method in the above embodiment is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program code.

[0163] The above is a detailed introduction to a lithium-rich manganese-based positive electrode working voltage recovery method, system, equipment and medium provided by the present application. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can refer to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. 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.

[0164] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A method for restoring the working voltage of a lithium-rich manganese-based positive electrode, characterized in that: include: Determine whether the current operating voltage of the lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than the preset operating voltage U of the lithium battery, and if so, let the current lithium battery stand for a first time t1 after the discharge is completed; Determine a first preset voltage U1, a second preset voltage U2, and a third preset voltage U3; Performing several rounds of first charging operations on the current lithium battery using the first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to the first preset voltage U1 and standing for a second time t2; Determine a second charging parameter D2 based on a judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and perform several rounds of second charging operations on the current lithium battery using the second charging parameter D2; each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3; The current lithium battery is discharged to the third preset voltage U3 using the preset discharge parameter D3, and is left standing for a fourth time t4, and then the current working voltage of the current lithium battery is detected to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored.

2. The method for restoring the working voltage of a lithium-rich manganese-based positive electrode according to claim 1, characterized in that: Detecting the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored includes: Detect the current working voltage of the current lithium battery to determine the current voltage recovery value; If the current voltage recovery value is less than the preset percentage value of the loss voltage, it is determined that the working voltage of the lithium-rich manganese-based positive electrode has not been recovered, and the process jumps back to the step of performing several rounds of first charging operations on the current lithium battery using the first charging parameter D1 at the preset temperature; When the current voltage recovery value is not less than the preset percentage value of the loss voltage, it is determined that the working voltage of the lithium-rich manganese-based positive electrode has been recovered.

3. The method for restoring the working voltage of a lithium-rich manganese-based positive electrode according to claim 2, characterized in that: Also includes: If the first preset voltage U1 is equal to the second preset voltage U2, the first charging parameter D1 is configured as a constant first preset charging current value and the preset discharging parameter D3 is configured as a constant first preset discharging current value; Furthermore, the second charging parameter D2 is used to perform several rounds of second charging operations on the current lithium battery, including: A plurality of rounds of second charging operations are performed on the current lithium battery using a target charging voltage value determined based on the first preset voltage U1 and a preset voltage increase value, and each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2, wherein the first preset voltage U1 and the target charging voltage value are both within a preset voltage range.

4. The method for restoring the working voltage of a lithium-rich manganese-based positive electrode according to claim 3, characterized in that: Also includes: If the target charging voltage value determined based on the first preset voltage U1 and the preset voltage increase value is greater than the upper limit value within the preset voltage range, the upper limit value is determined as the target charging voltage value.

5. The method for restoring the working voltage of a lithium-rich manganese-based positive electrode according to claim 2, characterized in that: Also includes: If the first preset voltage U1 is not equal to the second preset voltage U2, the first charging parameter D1 is configured as a constant second preset charging current value, the second charging parameter D2 is configured as a constant third preset charging current value, and the preset discharge parameter D3 is configured as a constant preset discharge current value; wherein the second preset charging current value, the third preset charging current value, and the preset discharge current value are all equal.

6. The method for restoring the working voltage of a lithium-rich manganese-based positive electrode according to claim 1, characterized in that: Before determining whether the current operating voltage of the lithium battery is less than the preset operating voltage U of the lithium battery, the method further includes: Determine whether the lithium battery has undergone a preset number of charge and discharge cycles; If so, the step of determining whether the current operating voltage of the lithium battery is less than the preset operating voltage U of the lithium battery is triggered.

7. The method for restoring the working voltage of a lithium-rich manganese-based positive electrode according to any one of claims 1 to 6, characterized in that: The preset temperature range is 20°C-55°C.

8. A lithium-rich manganese-based positive electrode working voltage recovery system, characterized in that: include: A judgment module, used to judge whether the current working voltage of the lithium battery corresponding to the lithium-rich manganese-based positive electrode is less than the preset working voltage U of the lithium battery, and if so, to stand for a first time t1 after the current lithium battery is discharged; A determination module, used to determine a first preset voltage U1, a second preset voltage U2 and a third preset voltage U3; A first operating module, configured to perform several rounds of first charging operations on the current lithium battery using a first charging parameter D1 within a preset temperature range; each round of the first charging operation includes charging the current lithium battery to the first preset voltage U1 and standing for a second time t2; a second operation module, configured to determine a second charging parameter D2 based on a judgment result of whether the first preset voltage U1 and the second preset voltage U2 are equal, and perform several rounds of second charging operations on the current lithium battery using the second charging parameter D2; each round of the second charging operation includes charging the current lithium battery to the second preset voltage U2 and standing for a third time t3; The third operation module is used to discharge the current lithium battery to the third preset voltage U3 using the preset discharge parameter D3, and stand for a fourth time t4, and then detect the current working voltage of the current lithium battery to determine whether the working voltage of the lithium-rich manganese-based positive electrode is restored.

9. An electronic device, characterized in that: comprising a memory for storing a computer program; A processor, configured to implement the steps of the method for restoring the working voltage of a lithium-rich manganese-based positive electrode as described in any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, the steps of the method for recovering the working voltage of the lithium-rich manganese-based positive electrode according to any one of claims 1 to 7 are implemented.

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