CN117543756A

CN117543756A - Battery charging and discharging method and device, electronic equipment and medium

Info

Publication number: CN117543756A
Application number: CN202311477755.6A
Authority: CN
Inventors: 刘璐; 方嘉琳; 李素丽
Original assignee: Zhuhai Cosmx Battery Co Ltd
Current assignee: Zhuhai Cosmx Battery Co Ltd
Priority date: 2023-11-07
Filing date: 2023-11-07
Publication date: 2024-02-09

Abstract

The application provides a battery charging and discharging method, a device, an electronic device and a medium, comprising the following steps: performing a first number of charge and discharge operations on the target battery based on the first charge and discharge strategy; acquiring the current capacity loss change rate of the target battery under the first number of charge and discharge; if the current capacity loss change rate is smaller than a first threshold value, repeatedly executing the steps of executing a first number of charge and discharge on the target battery based on a first charge and discharge strategy; otherwise, based on each positive electrode potential of the target battery under the current first number of charge and discharge, acquiring the current limiting potential of the positive electrode of the target battery; and taking the improvement strategy as a current first charge-discharge strategy, and repeatedly executing the steps of executing the first number of charge-discharge operations on the target battery based on the first charge-discharge strategy. The scheme can delay the irreversible capacity loss change rate of the battery, thereby prolonging the service life of the battery.

Description

Battery charging and discharging method and device, electronic equipment and medium

Technical Field

The present disclosure relates to the field of battery technologies, and in particular, to a method and an apparatus for charging and discharging a battery, an electronic device, and a medium.

Background

The battery is used as a green energy source and is widely applied to various industries, such as the fields of lithium ion batteries, computers, mobile phones and the like.

In the related art, a battery is charged based on a predetermined charge rate, and when the voltage of the battery reaches a predetermined cutoff voltage or a predetermined cutoff current, the charging is stopped, and then the discharging is performed, and the above-described process is repeatedly performed to realize the charging and discharging of the battery.

However, in practical applications, in order to increase the energy density of the battery, a higher upper limit voltage is usually set for charging, so that the positive electrode potential of the battery is higher, and thus, the positive electrode potential is closer to the limiting potential of the positive electrode material of the battery, and as the battery ages, the positive electrode potential value gradually increases, and the limiting potential also decreases. Therefore, in the related art, the situation that the positive electrode potential is greater than the limiting potential occurs, and when the positive electrode potential of the battery is greater than the limiting potential, the positive electrode material is subjected to phase change, and the stability of the positive electrode structure is damaged by the phase change, so that the irreversible capacity loss of the battery is increased, the available capacitance cliff type of the battery is reduced, and the service life of the battery is shortened.

Disclosure of Invention

The embodiment of the application provides a battery charging and discharging method, device, electronic equipment and medium, and aims to solve the problem that the service life of a battery is short due to the fact that irreversible capacity loss of the battery changes rapidly in related technologies.

In a first aspect, the present application provides a method for charging and discharging a battery, including: performing a first number of charge and discharge operations on the target battery based on the first charge and discharge strategy; for each charge and discharge, acquiring the positive electrode potential of the target battery when the target battery is fully charged and the first discharge capacity of the target battery; acquiring the current capacity loss change rate of the target battery under the first number of times of charge and discharge based on the first discharge capacity of the target battery under the current first number of times of charge and discharge and the first discharge capacity of the target battery under the previous first number of times of charge and discharge; if the current capacity loss change rate is smaller than a first threshold value, repeatedly executing the steps of executing a first number of charge and discharge on the target battery based on a first charge and discharge strategy; otherwise, acquiring the current limiting potential of the positive electrode of the target battery based on the positive electrode potential of the target battery under the condition of charging and discharging for each first number of times; and taking the improvement strategy as a current first charge-discharge strategy, and repeatedly executing the steps of executing the first number of charge-discharge operations on the target battery based on the first charge-discharge strategy.

In some embodiments, after the performing the first number of charge and discharge operations on the target battery based on the first charge and discharge strategy, the method further includes: acquiring a second discharge capacity of the current first number of charge and discharge of the target battery, wherein the second discharge capacity is the last charge and discharge of the current first number of charge and discharge of the target battery; the obtaining the current capacity loss change rate of the target battery based on the first discharge capacity of the target battery under the current first number of charge and discharge and the first discharge capacity of the target battery under the previous first number of charge and discharge comprises the following steps: the method comprises the steps of taking the difference between a second discharge capacity after the current first-number charge and discharge and a first discharge capacity of the first charge and discharge in the current first-number charge and discharge, dividing the difference by the first discharge capacity of the first charge and discharge in the current first-number charge and discharge, and obtaining the capacity loss rate under the current first-number charge and discharge; and acquiring the capacity loss change rate based on the current capacity loss rate under the first number of charge and discharge and the capacity loss rate under the previous first number of charge and discharge.

In some embodiments, the first charging strategy includes discharging the target battery based on a first discharge rate; the obtaining the second discharge capacity of the last charge and discharge of the current first number of charge and discharge of the target battery includes: performing primary charge and discharge on a target battery based on a second charge and discharge strategy, and acquiring a second discharge capacity of the target battery; the second charge-discharge strategy includes discharging the target battery based on a second discharge rate; the second discharge magnification is smaller than the first discharge magnification.

In some embodiments, the target battery includes a positive electrode, a negative electrode, and an auxiliary electrode connected between the positive and negative electrodes; before the first number of charging and discharging operations are performed on the target battery based on the first charging and discharging strategy, the method further comprises: performing charging for a first duration on a positive electrode and an auxiliary electrode of the target battery based on a first charging current; and performing charging for a first duration on an auxiliary electrode and a negative electrode of the target battery based on a first charging current to plate the auxiliary electrode such that a potential of the auxiliary electrode is a reference potential; the step of obtaining the positive electrode potential of the target battery when the target battery is fully charged for each charge and discharge includes: for each charge and discharge, a first voltage between a positive electrode and an auxiliary electrode of the target battery when the target battery is fully charged is obtained, and the positive electrode potential of the target battery is obtained based on the first voltage and the potential of the auxiliary electrode.

In some embodiments, the method of claim 1, the obtaining the current limiting potential of the positive electrode of the target battery based on the positive electrode potentials of the target battery at the first number of charge and discharge times, comprises: and taking the maximum potential of all the current positive electrode potentials under the first quantity of charge and discharge as the current limiting potential.

In some embodiments, the improvement strategy comprises: charging the target battery based on a first charging rate until the positive electrode potential of the target battery is not less than the current limiting potential, or the charging current of the target battery reaches the current cut-off current, or the voltage of the target battery reaches the current cut-off voltage, stopping charging, and discharging based on a first discharging rate; and if the positive electrode potential of the target battery is not smaller than the current limiting potential, the cut-off current is regulated or the cut-off voltage is reduced based on a first step length, and the regulated cut-off current is used as the current cut-off current or the regulated cut-off voltage is used as the current cut-off voltage.

In some embodiments, the improvement strategy comprises: charging the target battery based on a first charging rate, and stopping charging if the positive electrode potential of the target battery is not less than the current limiting potential; acquiring the current charging capacity of the target battery; and after standing for a first time period, repeatedly executing the step of charging the target battery based on the first charging multiplying power until the ratio of the current charging capacity to the first charging capacity of the target battery is smaller than a second threshold value, stopping charging, and discharging the target battery based on the first discharging multiplying power.

In some embodiments, the improvement strategy comprises: charging the target battery based on the current first charging rate, obtaining the positive electrode potential of the target battery, stopping charging if the positive electrode potential is not smaller than the limiting potential or the positive electrode potential reaches the cut-off voltage, and discharging based on the first discharging rate; and if the positive electrode potential is not smaller than the limiting potential when the charging is stopped, regulating the first charging rate based on the second step length, and taking the regulated first charging rate as the current first charging rate.

In a second aspect, the present application provides a charge and discharge device for a battery, including: the first charge-discharge module is used for executing a first number of charge-discharge operations on the target battery based on a first charge-discharge strategy; for each charge and discharge, acquiring the positive electrode potential of the target battery when the target battery is fully charged and the first discharge capacity of the target battery; the acquisition module is used for acquiring the current capacity loss change rate of the target battery based on the first discharge capacity of the target battery under the current first number of charge and discharge and the first discharge capacity of the target battery under the previous first number of charge and discharge; the processing module is used for repeatedly executing the steps of executing the first number of charge and discharge on the target battery based on the first charge and discharge strategy if the current capacity loss change rate is smaller than a first threshold value; the processing module is also used for acquiring the current limiting potential of the positive electrode of the target battery based on the positive electrode potential of the target battery under the condition of charging and discharging for each first number of times; and taking the improvement strategy as a current first charge-discharge strategy, and repeatedly executing the steps of executing the first number of charge-discharge operations on the target battery based on the first charge-discharge strategy.

In a third aspect, the present application provides an electronic device, comprising: a processor, and a memory communicatively coupled to the processor; the memory stores computer-executable instructions; the processor executes computer-executable instructions stored in the memory to implement the method as described above.

In a fourth aspect, the present application provides a computer readable storage medium having stored therein computer executable instructions which when executed by a processor are adapted to carry out the method as described above.

In the battery charging and discharging method, device, electronic equipment and medium, a first number of times of charging and discharging are performed on a target battery based on a first charging and discharging strategy, for each charging and discharging, the positive electrode potential of the target battery when the target battery is fully charged and the first discharging capacity of the target battery are obtained, the current capacity loss change rate of the target battery is obtained based on the first discharging capacity of the target battery under the current first number of times of charging and discharging and the first discharging capacity of the target battery under the previous first number of times of charging and discharging, when the current capacity loss change rate is not smaller than a first threshold value, the current limiting potential of the positive electrode of the target battery is obtained based on each positive electrode potential of the target battery under the current first number of times of charging and discharging, the improvement strategy is taken as a first charging strategy, and the steps of performing the first number of times of charging and discharging on the target battery based on the first charging and discharging strategy are repeatedly performed. According to the scheme, whether the current positive electrode potential of the battery is larger than the current limiting potential is monitored through the capacity loss change rate, and an improvement strategy is executed when the current positive electrode potential is larger than the current limiting potential, so that damage to a positive electrode structure is reduced, irreversible capacity loss of the battery is not increased any more, and the service life of the battery can be prolonged.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the embodiments of the application and together with the description, serve to explain the principles of the embodiments of the application.

Specific embodiments thereof have been shown by way of example in the drawings and will herein be described in more detail. These drawings and the written description are not intended to limit the scope of the inventive concepts of the embodiments in any way, but rather to illustrate the concepts of the embodiments of the present application to those skilled in the art by reference to the specific embodiments.

Fig. 1 is a schematic flow chart of a battery charging and discharging method according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a battery in an example;

FIG. 3 is a schematic cross-sectional view of the battery of the example of FIG. 2;

fig. 4 is a flow chart of another method for charging and discharging a battery according to an embodiment of the present disclosure;

FIG. 5 is a schematic diagram showing the relationship between the charge-discharge cycle and the capacity loss rate of the target batteries 1-7;

fig. 6 is a schematic structural diagram of a battery charging and discharging device according to an embodiment of the present disclosure;

fig. 7 is a schematic structural diagram of an electronic device according to a third embodiment of the present application.

Specific embodiments thereof have been shown by way of example in the drawings and will herein be described in more detail. These drawings and the written description are not intended to limit the scope of the inventive concepts in any way, but to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments.

Detailed Description

Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples are not representative of all implementations consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present application as detailed in the accompanying claims.

It should be noted that the brief description of the terms in the present application is only for convenience in understanding the embodiments described below, and is not intended to limit the embodiments of the present application. Unless otherwise indicated, these terms should be construed in their ordinary and customary meaning.

The terms first, second and the like in the description and in the claims and in the above-described figures are used for distinguishing between similar or similar objects or entities and not necessarily for describing a particular sequential or chronological order, unless otherwise indicated (Unless otherwise indicated). It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application are, for example, capable of operation in sequences other than those illustrated or otherwise described herein.

Furthermore, the terms "comprise" and "have," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a product or apparatus that comprises a list of elements is not necessarily limited to those elements expressly listed, but may include other elements not expressly listed or inherent to such product or apparatus. The term "circuitry" as used in this application refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and/or software code that is capable of performing the function associated with that element.

However, in practical applications, in order to increase the energy density of the battery, a higher upper limit voltage is usually set for charging, so that the positive electrode potential of the battery is higher, and thus, the positive electrode potential is closer to the limiting potential of the positive electrode material of the battery, and as the battery ages, the positive electrode potential value gradually increases, and the limiting potential also decreases. Therefore, in the related art, the situation that the positive electrode potential is greater than the limiting potential occurs, and when the positive electrode potential of the battery is greater than the limiting potential, the positive electrode material is subjected to phase change, and the stability of the positive electrode structure is damaged by the phase change, so that the irreversible loss of the battery is increased, the available capacitance cliff of the battery is reduced, and the service life of the battery is shortened.

In view of this, in the method for charging and discharging a battery provided in the embodiment of the present application, a first charging and discharging strategy of an operating system is executed to perform a first number of charging and discharging operations on the battery, and whether the current positive electrode potential of the battery is greater than the current limiting potential is monitored by the capacity loss change rate, if so, an improvement strategy is executed to control the positive electrode potential of the battery to be less than the limiting potential, so that damage to the positive electrode structure can be reduced, and irreversible capacity loss of the battery is not increased any more, thereby improving the service life of the battery.

The technical scheme of the present application and the technical scheme of the present application are described in detail below with specific examples. The following embodiments may be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments. In the description of the present application, the terms are to be construed broadly in the art, unless explicitly stated or defined otherwise. Embodiments of the present application will be described below with reference to the accompanying drawings.

Example 1

Fig. 1 is a schematic flow chart of a battery charging and discharging method provided in an embodiment of the present application, and an execution body of the method may be a battery charging and discharging device, where the charging and discharging device may be implemented in a hardware manner or may be implemented in a hardware-in-software manner. As shown in fig. 1, the method includes:

S101, performing a first number of charge and discharge on a target battery based on a first charge and discharge strategy; for each charge and discharge, acquiring the positive electrode potential of the target battery when the target battery is fully charged and the first discharge capacity of the target battery;

s102, acquiring a capacity loss change rate of the target battery under the current first number of times of charge and discharge based on the first discharge capacity of the target battery under the current first number of times of charge and discharge and the first discharge capacity of the target battery under the previous first number of times of charge and discharge;

s103, if the current capacity loss change rate is smaller than a first threshold value, repeatedly executing the steps of executing a first number of charge and discharge on the target battery based on a first charge and discharge strategy;

s104, otherwise, acquiring the current limiting potential of the positive electrode of the target battery based on the positive electrode potential of the target battery under the condition of charging and discharging for a first number of times; and taking the improvement strategy as a current first charge-discharge strategy, and repeatedly executing the steps of executing the first number of charge-discharge operations on the target battery based on the first charge-discharge strategy.

In this embodiment, the target battery includes, but is not limited to, a lithium ion battery. The first charging and discharging strategy can be used for charging and discharging based on the charging and discharging strategy under the normal working system when the first charging and discharging strategy is initially charged. By way of example, normal operating regimes may include: charging the target battery based on a first charging rate until the target battery is full; and discharging the target battery based on the first discharging multiplying power until the voltage of the target battery reaches a first preset voltage. Different working modes can be set based on a State of Charge (SOC), for example, when the SOC is smaller than a first value, the target battery is charged based on a first charging rate, and when the SOC is not smaller than the first value, the target battery is charged based on a second charging rate, and the first discharging rate is larger than the second discharging rate; and discharging the target battery based on the first discharge rate. The first charge rate and the first discharge rate may be specifically set based on parameters such as the rated capacity of the target battery. When the charging and discharging are performed based on the first charging rate, a constant-current charging mode, a constant-voltage charging mode, a constant-current charging mode and a constant-voltage charging mode can be adopted, and the specific form is not limited in the embodiment. Taking a constant-current and constant-voltage charging mode as an example, constant-current charging is firstly based, when the target battery reaches a preset voltage, constant-voltage charging is switched to, and when the charging current reaches the cut-off current, the target battery is fully charged.

It should be noted that, in some examples, after the target battery is fully charged, the target battery may still stand for a period of time, and after standing, the target battery is discharged based on the first discharge rate, so that polarization generated in the charging process of the target battery can be reduced. Other charging strategies in the following examples may also be performed after the charging is performed fully as described above, and then the charging is performed for a period of time, which will not be described in detail in the following embodiments.

The first number in this embodiment may be set based on the actual parameters of the battery, and the smaller the first number is, the higher the detection accuracy is, so that the current state of the positive electrode potential can be rapidly identified. However, too small a first number may increase the computational throughput, which may burden the main body of the method, for example, 50 times.

S101 further includes acquiring, for each charge and discharge, the positive electrode potential of the target battery when the target battery is fully charged and the first discharge capacity of the target battery. Wherein the accuracy of the positive electrode potential detection directly affects the subsequent judgment result. In practical applications, the positive electrode and the negative electrode of the target battery are polarized, and the polarization affects the potentials of the positive electrode and the negative electrode, that is, the potential of the negative electrode is not zero and can change, so that the positive electrode potential obtained based on the voltage of the target battery may be inaccurate.

To this end, in some examples, a target battery includes a positive electrode, a negative electrode, and an auxiliary electrode connected between the positive electrode and the negative electrode, and on the basis of this, the obtaining, for each charge and discharge in S101, a positive electrode potential of the target battery when fully charged includes:

for each charge and discharge, a first voltage between a positive electrode and an auxiliary electrode of the target battery when the target battery is fully charged is obtained, and the positive electrode potential of the target battery is obtained based on the first voltage and the potential of the auxiliary electrode.

In this example, the auxiliary electrode is an electrode of known potential and close to ideal unpolarized, and substantially no current passes through the auxiliary electrode for determining the potential of the electrode under investigation. Specifically, the substrate of the auxiliary electrode may be graphite, copper, platinum, or other metals, and the auxiliary electrode is formed by electroplating, and fig. 2 is a schematic structural diagram of a battery in an example, as shown in fig. 2, where the battery includes a winding core and a separator, and the winding core includes a positive plate, a negative plate, and an auxiliary plate disposed between the positive plate and the negative plate, and fig. 3 is an exemplary schematic sectional diagram of the battery in the example of fig. 2, and as shown in fig. 3, the auxiliary plate may be disposed at a third fold of the winding core and located at a 1/2 arc of the length of the winding core. The auxiliary electrode is arranged, and the reference potential is provided through the auxiliary electrode, so that the accuracy of the obtained positive electrode potential can be improved.

Based on the above examples, in some examples, before the performing the first number of charge and discharge operations on the target battery based on the first charge and discharge policy, the method further includes: performing charging for a first duration on a positive electrode and an auxiliary electrode of the target battery based on a first charging current; and performing charging for a first duration on the auxiliary electrode and the negative electrode of the target battery based on the first charging current to plate the auxiliary electrode such that the potential of the auxiliary electrode is a reference potential.

In practical application, the electroplated layer outside the auxiliary electrode gradually fades along with the progress of the battery reaction, so that the electroplating of the auxiliary electrode is carried out once before the target battery is charged and discharged for the first number of times based on the first charging and discharging strategy every time, the auxiliary electrode can be protected, and the accuracy of the potential of the auxiliary electrode can be improved.

In S102, the current capacity loss change rate of the target battery is obtained based on the first discharge capacity of the target battery under the current first number of charge and discharge and the first discharge capacity of the target battery under the previous first number of charge and discharge. It can be understood that the current capacity change rate characterizes the rate of change of the capacity loss under the current first number of charge and discharge, and that the larger the rate of change of the capacity loss, the more likely the structure of the positive electrode is damaged, and conversely, the more stable the positive electrode is. For a specific acquisition method, in one example, after the performing, based on the first charge-discharge policy, a first number of charge-discharge operations on the target battery, the method further includes:

Acquiring a second discharge capacity of the current first number of charge and discharge of the target battery, wherein the second discharge capacity is the last charge and discharge of the current first number of charge and discharge of the target battery;

s102 may include:

the method comprises the steps of taking the difference between a second discharge capacity after the current first-number charge and discharge and a first discharge capacity of the first charge and discharge in the current first-number charge and discharge, dividing the difference by the first discharge capacity of the first charge and discharge in the current first-number charge and discharge, and obtaining the capacity loss rate under the current first-number charge and discharge;

and acquiring the capacity loss change rate based on the current capacity loss rate under the first number of charge and discharge and the capacity loss rate under the previous first number of charge and discharge.

The present example provides a method of calculating a rate of change of capacity loss. An exemplary description will be made below in connection with an actual scenario. Setting a first number of charge and discharge for n and a first number of current mth week, wherein each first discharge capacity is C in turn _m1 、C _m2 、C _m3 …C _mn . Then obtaining a second discharge capacity Bm under the n+1th charge-discharge, wherein the second discharge capacity between 1 and m weeks is sequentially B ₁ 、B ₂ ……B _m The current calculation formula of the capacity loss rate is:

Loss _m ＝(C _m1 -B _m )/C ₁

current rate of change of capacity loss

Δε＝(Loss _n -Loss _n-1 )/(Loss _n-1 -Loss _n-2 )

In this embodiment, if the rate of change of the capacity loss does not exceed the first threshold, it indicates that the current positive electrode of the battery does not exceed the limiting potential, and charging of the target battery may be continued based on the first charging policy. Otherwise, if the change rate of the capacity loss exceeds the first threshold, the current capacity loss exceeds the normal battery loss, and therefore the positive electrode structure of the battery may be damaged. In general, the inversion problem of the target battery does not occur when the target battery is charged and discharged a first number of times in the first few weeks, and thus the target battery can start to acquire the capacity loss change rate after the 2 nd first number of times of charging based on the first charge and discharge strategy.

The method for obtaining the second discharge capacity may include multiple methods, and as an implementation manner, the method may perform charging and discharging on the target battery based on the first charging policy, where the first charging and discharging policy may perform discharging on the target battery based on the first discharging magnification, so as to obtain the second discharge capacity.

As another implementation manner, the obtaining the second discharge capacity of the last charge and discharge of the current first number of charge and discharge of the target battery includes: performing primary charge and discharge on a target battery based on a second charge and discharge strategy, and acquiring a second discharge capacity of the target battery; the second charge-discharge strategy includes discharging the target battery based on a second discharge rate; the second discharge magnification is smaller than the first discharge magnification.

In practical application, the smaller the discharge rate is, the longer the discharge time is, the lighter the polarization phenomenon of the electrode is, and the battery can discharge more capacity, so that the influence of the polarization of the battery on the discharge capacity can be reduced, and the accuracy of the obtained second discharge capacity can be improved in the embodiment.

In S104, a current limiting potential of the positive electrode of the target battery is obtained based on each positive electrode potential of the target battery in each first number of charge and discharge. And then, taking the improvement strategy as a first charging strategy, and repeatedly executing the steps of executing the first number of charging and discharging on the target battery based on the first charging and discharging strategy.

As an example, S104 may include: and taking the maximum potential of all the current positive electrode potentials under the first quantity of charge and discharge as the current limiting potential. For example, the first number is n, if 3 cycles are performed, the current charge and discharge times are 3n, and the positive electrode potential is V in turn ₁ 、V ₂ 、V ₂ ……V _3n ，V _max ＝Max(V ₁ 、V ₂ 、V ₂ ……V _3n )。

The flow of the present embodiment will be exemplarily described below: fig. 4 is a flow chart of another method for charging and discharging a battery according to an embodiment of the present application, as shown in fig. 4, in which a target battery is charged and discharged based on a first charging strategy under an initial operating system, and then after each execution of a first number of charging and discharging operations, a capacity loss change rate is detected once, and if the capacity loss change rate is smaller than a first threshold, it indicates that an anode potential of the target battery in the first number of charging and discharging operations is smaller than a limiting potential, charging may be continued based on a current first charging and discharging strategy. If the capacity loss change rate is not smaller than the first threshold, indicating that the positive electrode potential of the target battery is larger than the limiting potential in the first number of times of charging and discharging, obtaining the current limiting potential, taking the improvement strategy as a first charging and discharging strategy, carrying out the first number of times of charging and discharging on the target battery based on the improvement strategy, and controlling the positive electrode potential to be smaller than the limiting potential through the improvement strategy. And then executing the first number of charge and discharge, detecting the current capacity loss change rate, if the capacity loss change rate is not smaller than a first threshold value, indicating that the current limiting potential is smaller than the potential detected in the previous week, and needing to return to the current limiting potential again.

The improvement strategy may include a variety of strategies, and will be described by way of example.

In some examples, the improvement policy may include:

charging the target battery based on a first charging rate until the positive electrode potential of the target battery is not less than the current limiting potential, or the charging current of the target battery reaches the current cut-off current, or the voltage of the target battery reaches the current cut-off voltage, stopping charging, and discharging based on a first discharging rate;

and if the positive electrode potential of the target battery is not smaller than the current limiting potential, the cut-off current is regulated or the cut-off voltage is reduced based on a first step length, and the regulated cut-off current is used as the current cut-off current or the regulated cut-off voltage is used as the current cut-off voltage.

The off-current in this example means that in constant-voltage charging, the charging current becomes gradually smaller, and charging is not performed when it is as small as a predetermined current value, which is the off-current. Also, in the constant voltage charging process, the charging voltage is gradually increased, and when the charging voltage reaches a predetermined voltage value, the charging is stopped, and the predetermined voltage value is the off-voltage. And charging the target battery based on the first charging rate, if the charging current reaches the current cut-off current or the charging voltage reaches the current cut-off voltage, the current target battery is fully charged, the charging can be stopped at the moment, and the scene also shows that the current positive electrode voltage does not exceed the limit voltage. If the positive electrode potential of the target battery is not less than the current positive electrode potential, stopping charging, and the scene also shows that the positive electrode potential reaches the limiting potential on the premise that the target battery is not fully charged. In practical application, when the constant voltage is charged, the smaller the off current is, the smaller the chargeable capacitance is, and the higher the positive voltage is, otherwise, the lower the positive voltage is. The positive electrode voltage of the target battery is controlled to be less than the limit voltage by increasing the cutoff current or decreasing the cutoff voltage in this example.

For example, the current vmax=4.85V, the off-current is I _Z =0.05a, the first step is 0.05V. Begin to execute the improvement strategy based on the first charging rate CH ₁ Charging the target battery if the current positive electrode potential V _C Stopping charging when the voltage is more than or equal to 4.85V and based on the first charging multiplying power CH ₁ Discharging to a first preset voltage to finish discharging. And increase the off-current to I _Z =0.055A as the present off current. Then based on the first charging rate CH ₁ Charging the target battery if the current positive electrode potential V is still detected _C Stopping charging if the voltage is more than or equal to 4.85V, continuing to increase the cut-off current, and repeatedly executing the charging based on the first charging multiplying power CH ₁ Charging the target battery until the current I is the current _C ＝I _Z when=0.070A, V _C <4.85V. The charging and discharging may be continuously performed based on the current off-current until the first number of charging and discharging is performed.

In this example, the positive electrode voltage of the target battery is controlled to be less than the limit voltage by increasing the off-current, and the stability of the positive electrode is further improved, thereby prolonging the service life of the battery.

In other examples, the step of charging and discharging the target battery based on the improvement policy until the repair completion condition of the target battery is reached, repeatedly performing a first number of charges and discharges on the target battery based on the first charge and discharge policy, includes:

Charging the target battery based on a first charging rate, and stopping charging if the positive electrode potential of the target battery is not less than the current limiting potential; acquiring the current charging capacity of the target battery;

and after standing for a first time period, repeatedly executing the step of charging the target battery based on the first charging multiplying power until the ratio of the current charging capacity to the first charging capacity of the target battery is smaller than a second threshold value, stopping charging, and discharging the target battery based on the first discharging multiplying power.

In this example, the charging capacity refers to the capacity of the target battery when the target battery is charged, and due to phenomena such as polarization of the target battery, some reversible capacity loss occurs in the target battery, the polarization of the battery after a period of rest is reduced or eliminated, and then the positive electrode potential is reduced, and the capacity loss generated by the positive electrode potential being greater than the limiting potential is irreversible, so that the positive electrode potential is reduced by means of rest, the reversible capacity loss is eliminated, and then the step of charging the target battery is repeatedly performed until the ratio of the current charging capacity to the first charging capacity is less than the second threshold.

For example, V _C When the charging capacity is not smaller than Vmax, stopping charging and obtaining the current charging capacity C _a1 After standing for 0.2h, the battery is based on the first charging multiplying power CH again ₁ Charging if V _C Not less than Vmax, stopping charging again, and obtaining the current charging capacity C _a2 After standing for 0.2h, repeating the process based on the first charging rate CH ₁ Charging until the nth charge, obtaining the current charge capacity C _an And C _an /C _a1 This also indicates that the target cell is substantially saturated and then based on the first discharge rate DH ₁ And performing discharge.

This example is through keeping stand the depolarization to the target battery after charging for the positive pole potential reduces, then can charge partial electric capacity again like this, and therefore this example can guarantee that the positive pole potential of target battery is less than the limiting potential, can also improve the energy density of battery simultaneously.

In still other examples, S104 may include:

charging the target battery based on the current first charging rate, obtaining the positive electrode potential of the target battery, stopping charging if the positive electrode potential is not smaller than the limiting potential or the positive electrode potential reaches the cut-off voltage, and discharging based on the first discharging rate;

and if the positive electrode potential is not smaller than the limiting potential when the charging is stopped, regulating the first charging rate based on the second step length, and taking the regulated first charging rate as the current first charging rate.

In this example, the positive electrode potential of the target battery is not less than the limiting potential, the charging is stopped, the discharging is performed based on the first discharging magnification, the current first charging magnification is adjusted to be low, the charging is performed based on the first charging magnification after the adjustment in next charging, the polarization phenomenon of the battery is reduced by reducing the charging magnification, so that more capacity can be charged, and the capacity density of the target battery is improved.

For example, when the capacity loss change rate is detected to be higher than the first threshold value, the current vmax=4.55v, the second step length 2%ch1, the current first charging rate is 4.9C, the target battery is charged based on the first charging rate being 4.9C, if V _C Not less than Vmax, the charging is stopped, and the discharging is performed based on the first charging magnification DH 1. Regulating the first charging rate to 4.8C, then charging based on 4.8C, if V _C And stopping charging and discharging based on the first charging rate DH1, wherein Vmax is not smaller. And (3) regulating the first charging multiplying power to 4.7 ℃ again, and repeatedly executing the process until V when the first charging multiplying power is regulated to 4.2 DEG C _C Less than Vmax, then the target battery continues to be discharged based on 4.2C.

In the example, the target battery is charged in a manner of decreasing the first charging rate, so that the positive voltage of the target battery is controlled to be smaller than the limit voltage, and meanwhile, the polarization of the electrode can be reduced, and the energy density of the target battery is improved.

The present embodiment will be exemplarily described below in connection with actual scenes: in order to test the effect of the solution of the embodiment, the same target battery 1-7 is used as a test sample, and different charge and discharge methods are respectively adopted to test the sample, which is specifically as follows:

first, the plating of the auxiliary electrode is completed. The method comprises the following steps: the positive electrode and the auxiliary electrode of the target battery 1-5 are respectively charged, the charging current is 20 mu A, the charging time period is 5h, and the negative electrode and the auxiliary electrode of the target battery 1-5 are respectively charged, the charging current is 20 mu A, and the charging time period is 5h.

Then, for the target battery 1-5, charge and discharge are cycled 50 times (a first number of 50) based on the first charge and discharge strategy under the current operation system including: at a first charging rate CH ₁ Constant current charging is carried out by the method of the invention, the charging is carried out to 4.4V, the constant voltage charging is carried out, when the charging current reaches the cut-off current of 0.05A, the charging (full charging) is stopped, and the method of the invention is carried out, and the method of the invention is characterized in that t ₁ After=10 min, at a first discharge rate DC ₁ The target battery was discharged to 3V by =0.7c, and the discharge was stopped. Acquiring the positive voltage V of the target battery 1-3 when charging is stopped for 1-50 times ₁ 、V ₂ ......V ₅₀ First discharge capacity C of 1-50 times ₁ 、C ₂ ......C ₅₀ 。

Next, the capacity loss change rate of the target battery 1-5 is acquired, specifically including: discharging the target battery 1-3 based on a second charge-discharge strategy, specifically constant-current charging to full charge at a first charge rate ch1=5c, and a second discharge rate DC ₂ =0.04C to 3V, and the second discharge magnification B1 of the target battery 1-3 is acquired, respectively. The capacity loss change rate of each target battery is not acquired before the 3 rd first number of charge and discharge. At the time of the 3 rd first number of charge and discharge, i.e., at the time of 100-150 charge and discharge, the charge and discharge is performed based on the formula Δε= (Loss _n -Loss _n-1 )/(Loss _n-1 -Loss _n-2 ) Acquiring the current capacity loss change rate delta epsilon < 1 of each target battery, repeatedly executing the electroplating of the auxiliary electrode and the circulation based on the first charge-discharge strategy under the current working systemAnd (3) charging and discharging for 50 times, wherein after the mth 50 times of charging and discharging, delta epsilon of the target battery 1-3 is more than or equal to 1, which indicates that the positive electrode voltage of the target battery 1-3 is larger than the limit voltage. Acquiring the limit voltage V in the mth 50-th charge and discharge of the target battery 1-3 _max ＝Max(V ₁ 、V ₂ 、V ₂ ……V _n )＝4.55V。

Different improvement strategies are respectively executed for the target battery 1-3, specifically, the improvement strategy 1 is taken as a first charge-discharge strategy, and 50 times of charge-discharge are executed for the target battery 1 based on the first charge-discharge strategy. Wherein improving strategy 1 comprises: the cut-off voltage is reduced to less than the limiting potential, such as by reducing the cut-off voltage to 4.5V. Then based on the first charging rate CH ₁ Charging is carried out by =5c until the positive electrode potential reaches 4.5V, and the charging is stopped based on the first discharge rate DC ₁ Discharge was performed=0.7c. After repeating the charge 50 times, obtaining the capacity loss change rate delta epsilon of the target battery 1 again, if delta epsilon 1 is less than 1, repeating the charge and discharge based on the current improvement strategy, and if delta epsilon 1 is more than or equal to 1, executing a second charge and discharge strategy to obtain the current V _max . The step of performing charge and discharge on the target battery 1 50 times based on the first charge and discharge strategy is then repeated to circulate by adjusting the cutoff voltage based on the current Vmax. Regarding the target battery 2, taking the improvement policy 2 as a first charge-discharge policy, performing 50 times of charge-discharge on the target batteries 2, 3, 4 based on the first charge-discharge policy, the improvement policy 2 including: charging the target battery based on the first charging rate ch1=5c, and if the positive electrode potential V of the target battery 2 is the same _C Stopping charging, obtaining charged charging capacity Ca1, standing for a first time period t1, then charging the target battery based on a first charging rate CH1=5C, standing for a first time period t1, obtaining charging capacity Ca2, and repeating the process until Ca _n Ca1 is less than 1%. Based on the first discharge rate DC ₁ Discharge was performed=0.7c. In the improvement strategy 2 executed on the target battery 2, t1=0.25 h, t1=0.5 h of the target battery 3, and t1=5 h of the target battery 4. Regarding the target battery 5, the improvement policy 3 is taken as a first charge-discharge policy, and charge-discharge is performed on the target battery 5 based on the first charge-discharge policy, wherein the improvement policy 3 includes: in 2% CH1 is a second step length, the target battery 5 is charged by the first charging rate ch1=4.9c, if V is detected _C Not less than Vmax, stopping charging, based on the first discharge rate DC ₁ Discharging with the first charge rate adjusted to 4.8C, and then recharging if V is detected _C Not less than Vmax, stopping charging, based on the first discharge rate DC ₁ The discharge is performed with =0.7c, repeating the charge and discharge until V _C When adjusting to 4.2C, V _C Less than Vmax, no longer turned down, repeated with DC ₁ Charging was performed=0.7c.

For the target battery 6, charge and discharge are cycled based on the first charge and discharge strategy in the operating regime. For the target battery 7, the charge and discharge are circulated based on the first charge and discharge strategy under the operation system, when the larger change rate of the capacity loss is detected, the charge upper limit voltage, that is, the cutoff voltage of the target battery 7 is set to be the theoretical value of 4.39V, and then the charge and discharge are circulated based on the first charge and discharge strategy that the cutoff voltage is 4.39V.

After the test, fig. 5 is a schematic diagram showing the relationship between the charge-discharge cycle and the capacity loss rate of the target battery 1-7, as shown in fig. 5, the capacity loss rate of the target battery 1-5 is far lower than that of the target batteries 6 and 7, wherein the order of the capacity loss rate of the target battery 1-5 from high to low is the target battery 4, the target battery 3, the target battery 2, the target battery 1, and the target battery 5. As shown by test results, the embodiment of the application can delay the attenuation of the capacity loss of the target battery, so that the service life of the target battery can be prolonged.

Example two

Fig. 6 is a schematic structural diagram of a battery charging and discharging device according to an embodiment of the present application, and as shown in fig. 6, the battery charging and discharging device includes:

a first charge-discharge module 61 for performing a first number of charge-discharge operations on the target battery based on a first charge-discharge strategy; for each charge and discharge, acquiring the positive electrode potential of the target battery when the target battery is fully charged and the first discharge capacity of the target battery;

an obtaining module 62, configured to obtain a current capacity loss change rate of the target battery based on a first discharge capacity of the target battery under a current first number of charge and discharge cycles and a first discharge capacity of the target battery under a previous first number of charge and discharge cycles;

a processing module 63, configured to repeatedly execute the step of executing the first number of charging and discharging operations on the target battery based on the first charging and discharging policy if the current capacity loss change rate is less than a first threshold;

the processing module 63 is further configured to obtain a current limiting potential of the positive electrode of the target battery based on each positive electrode potential of the target battery under each first number of charge and discharge cycles if the current capacity loss change rate is not less than a first threshold; and taking the improvement strategy as a current first charge-discharge strategy, and repeatedly executing the steps of executing the first number of charge-discharge operations on the target battery based on the first charge-discharge strategy.

In this embodiment, the first charge-discharge strategy may perform charge-discharge based on the charge-discharge strategy under the normal operation system during initial charge. By way of example, normal operating regimes may include: charging the target battery based on a first charging rate until the target battery is full; and discharging the target battery based on the first discharging multiplying power until the voltage of the target battery reaches a first preset voltage. The first number in this embodiment may be set based on the actual parameters of the battery, and the smaller the first number is, the higher the detection accuracy is, so that the current state of the positive electrode potential can be rapidly identified. However, too small a first number may increase the computational throughput, which may burden the main body of the method, for example, 50 times.

The first charge/discharge module 61 also obtains the positive electrode potential of the target battery when the target battery is fully charged and the first discharge capacity of the target battery for each charge/discharge. Wherein the accuracy of the positive electrode potential detection directly affects the subsequent judgment result. In practical applications, the positive electrode and the negative electrode of the target battery are polarized, and the polarization affects the potentials of the positive electrode and the negative electrode, that is, the potential of the negative electrode is not zero and can change, so that the positive electrode potential obtained based on the voltage of the target battery may be inaccurate.

To this end, in some examples, the target battery includes a positive electrode, a negative electrode, and an auxiliary electrode connected between the positive electrode and the negative electrode, and the battery charging and discharging device may further include: the second charge-discharge module is used for acquiring a second discharge capacity of the last charge-discharge of the current first number of charge-discharge of the target battery after the first number of charge-discharge of the target battery is executed based on the first charge-discharge strategy;

the processing module 63 is further configured to make a difference between the second discharge capacity after the current first number of charges and discharges and the first discharge capacity of the first charge and discharge in the current first number of charges and discharges, and divide the difference by the first discharge capacity of the first charge and discharge in the current first number of charges and discharges, so as to obtain a capacity loss rate under the current first number of charges and discharges;

On the basis of the above examples, in some examples, the second charge-discharge module is further configured to perform charging on the positive electrode and the auxiliary electrode of the target battery for a first duration based on the first charging current before performing the first number of charge-discharge operations on the target battery based on the first charge-discharge strategy; and performing charging for a first duration on the auxiliary electrode and the negative electrode of the target battery based on the first charging current to plate the auxiliary electrode such that the potential of the auxiliary electrode is a reference potential.

The obtaining module 62 obtains a current capacity loss change rate of the target battery based on the first discharge capacity of the target battery under the current first number of charge and discharge and the first discharge capacity of the target battery under the previous first number of charge and discharge. It can be understood that the current capacity change rate characterizes the rate of change of the capacity loss under the current first number of charge and discharge, and that the larger the rate of change of the capacity loss, the more likely the structure of the positive electrode is damaged, and conversely, the more stable the positive electrode is. For a specific acquisition method, in one example, the battery charging and discharging device may further include:

the third charge-discharge module is used for acquiring a second discharge capacity of the last charge-discharge of the current first number of charge-discharge of the target battery after the first number of charge-discharge of the target battery is executed based on the first charge-discharge strategy;

The obtaining module 62 may specifically be configured to make a difference between the second discharge capacity after the current first number of charges and discharges and the first discharge capacity of the first charge and discharge in the current first number of charges and discharges, and divide the difference by the first discharge capacity of the first charge and discharge in the current first number of charges and discharges to obtain a capacity loss rate under the current first number of charges and discharges;

As another implementation manner, the obtaining module 62 is specifically configured to perform one charge and discharge on the target battery based on the second charge and discharge policy, and obtain the second discharge capacity of the target battery; the second charge-discharge strategy includes discharging the target battery based on a second discharge rate; the second discharge magnification is smaller than the first discharge magnification.

The processing module 63 obtains the current limiting potential of the positive electrode of the target battery based on the positive electrode potential of the target battery under the current first number of charge and discharge. Specifically, the maximum potential among the positive electrode potentials at the current first number of charge and discharge times may be used as the current limiting potential.

In some examples, the improvement policy may include:

The off-current in this example means that in constant-voltage charging, the charging current becomes gradually smaller, and charging is not performed when it is as small as a predetermined current value, which is the off-current. Also, in the constant voltage charging process, the charging voltage is gradually increased, and when the charging voltage reaches a predetermined voltage value, the charging is stopped, and the predetermined voltage value is the off-voltage. And charging the target battery based on the first charging rate, if the charging current reaches the current cut-off current or the charging voltage reaches the current cut-off voltage, the current target battery is fully charged, the charging can be stopped at the moment, and the scene also shows that the current positive electrode voltage does not exceed the limit voltage. If the positive electrode potential of the target battery is not less than the current positive electrode potential, stopping charging, and the scene also shows that the positive electrode potential reaches the limiting potential on the premise that the target battery is not fully charged. In practical application, when the constant voltage is charged, the smaller the off current is, the smaller the chargeable capacitance is, and the higher the positive voltage is, otherwise, the lower the positive voltage is. The positive electrode voltage of the target battery is controlled to be less than the limit voltage by increasing the cutoff current or decreasing the cutoff voltage in this example. In this example, the positive electrode voltage of the target battery is controlled to be less than the limit voltage by increasing the off-current, and the stability of the positive electrode is further improved, thereby prolonging the service life of the battery.

In still other examples, the improvement policy may include:

In the battery charging and discharging device provided by the application, the first charging and discharging module executes first number of times of charging and discharging on the target battery based on the first charging and discharging strategy, the acquisition module acquires the positive electrode potential of the target battery when the target battery is fully charged and the first discharging capacity of the target battery for each time of charging and discharging, the processing module acquires the current capacity loss change rate of the target battery based on the first discharging capacity of the target battery under the current first number of times of charging and discharging and the first discharging capacity of the target battery under the previous first number of times of charging and discharging, and acquires the current limiting potential of the positive electrode of the target battery based on each positive electrode potential of the target battery under the current first number of times of charging and discharging when the current capacity loss change rate is not less than a first threshold value, and takes the improvement strategy as the first charging strategy. According to the scheme, whether the current positive electrode potential of the battery is larger than the current limiting potential is monitored through the capacity loss change rate, and an improvement strategy is executed when the current positive electrode potential is larger than the current limiting potential, so that damage to a positive electrode structure is reduced, irreversible capacity loss of the battery is not increased any more, and the service life of the battery can be prolonged.

Example III

Fig. 7 is a schematic structural diagram of an electronic device according to a third embodiment of the present application, as shown in fig. 7, where the electronic device includes:

a processor 291, the electronic device further comprising a memory 292; a communication interface (Communication Interface) 293 and bus 294 may also be included. The processor 291, the memory 292, and the communication interface 293 may communicate with each other via the bus 294. Communication interface 293 may be used for information transfer. The processor 291 may call logic instructions in the memory 292 to perform the methods of the above-described embodiments.

Further, the logic instructions in memory 292 described above may be implemented in the form of software functional units and stored in a computer-readable storage medium when sold or used as a stand-alone product.

The memory 292 is a computer readable storage medium, and may be used to store a software program, a computer executable program, and program instructions/modules corresponding to the methods in the embodiments of the present application. The processor 291 executes functional applications and data processing by running software programs, instructions and modules stored in the memory 292, i.e., implements the methods of the method embodiments described above.

Memory 292 may include a storage program area that may store an operating system, at least one application program required for functionality, and a storage data area; the storage data area may store data created according to the use of the terminal device, etc. Further, memory 292 may include high-speed random access memory, and may also include non-volatile memory.

Embodiments of the present application also provide a computer-readable storage medium having stored therein computer-executable instructions that, when executed by a processor, are configured to implement the method described in any of the embodiments.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the application pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

It is to be understood that the present application is not limited to the precise arrangements and instrumentalities shown in the drawings, which have been described above, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the application is limited only by the appended claims.

Claims

1. A method of charging and discharging a battery, comprising:

performing a first number of charge and discharge operations on the target battery based on the first charge and discharge strategy; for each charge and discharge, acquiring the positive electrode potential of the target battery when the target battery is fully charged and the first discharge capacity of the target battery;

acquiring the current capacity loss change rate of the target battery under the first number of times of charge and discharge based on the first discharge capacity of the target battery under the current first number of times of charge and discharge and the first discharge capacity of the target battery under the previous first number of times of charge and discharge;

if the current capacity loss change rate is smaller than a first threshold value, repeatedly executing the steps of executing a first number of charge and discharge on the target battery based on a first charge and discharge strategy;

otherwise, acquiring the current limiting potential of the positive electrode of the target battery based on the positive electrode potential of the target battery under the condition of charging and discharging for each first number of times; and taking the improvement strategy as a current first charge-discharge strategy, and repeatedly executing the steps of executing the first number of charge-discharge operations on the target battery based on the first charge-discharge strategy.

2. The method of claim 1, wherein after performing a first number of charge and discharge operations on the target battery based on the first charge and discharge strategy, further comprising:

the obtaining the current capacity loss change rate of the target battery based on the first discharge capacity of the target battery under the current first number of charge and discharge and the first discharge capacity of the target battery under the previous first number of charge and discharge comprises the following steps:

the method comprises the steps of taking a difference between a second discharge capacity after current first-time charge and discharge and a first discharge capacity of first-time charge and discharge in the current first-time charge and discharge, dividing the difference by the first discharge capacity of first-time charge and discharge in the current first-time charge and discharge, and obtaining a capacity loss rate under the current first-time charge and discharge;

3. The method of claim 2, wherein the first charging strategy comprises discharging the target battery based on a first discharge rate;

The obtaining the second discharge capacity of the last charge and discharge of the current first number of charge and discharge of the target battery includes: performing primary charge and discharge on a target battery based on a second charge and discharge strategy, and acquiring a second discharge capacity of the target battery; the second charge-discharge strategy includes discharging the target battery based on a second discharge rate; the second discharge magnification is smaller than the first discharge magnification.

4. The method of claim 1, wherein the target cell comprises a positive electrode, a negative electrode, and an auxiliary electrode connected between the positive and negative electrodes; before the first number of charging and discharging operations are performed on the target battery based on the first charging and discharging strategy, the method further comprises:

performing charging for a first duration on a positive electrode and an auxiliary electrode of the target battery based on a first charging current; and performing charging for a first duration on the auxiliary electrode and the negative electrode of the target battery based on a first charging current;

the step of obtaining the positive electrode potential of the target battery when the target battery is fully charged for each charge and discharge includes:

5. The method of claim 1, wherein the obtaining the current limiting potential of the positive electrode of the target battery based on the positive electrode potentials of the target battery at the first number of charge and discharge times comprises:

and taking the maximum potential of all the current positive electrode potentials under the first quantity of charge and discharge as the current limiting potential.

6. The method of any one of claims 1-5, wherein the improvement strategy comprises:

7. The method of any one of claims 1-5, wherein the improvement strategy comprises:

8. The method of any one of claims 1-5, wherein the improvement strategy comprises:

9. A battery charging and discharging device, comprising:

the first charge-discharge module is used for executing a first number of charge-discharge operations on the target battery based on a first charge-discharge strategy; for each charge and discharge, acquiring the positive electrode potential of the target battery when the target battery is fully charged and the first discharge capacity of the target battery;

the acquisition module is used for acquiring the current capacity loss change rate of the target battery based on the first discharge capacity of the target battery under the current first number of charge and discharge and the first discharge capacity of the target battery under the previous first number of charge and discharge;

the processing module is used for repeatedly executing the steps of executing the first number of charge and discharge on the target battery based on the first charge and discharge strategy if the current capacity loss change rate is smaller than a first threshold value;

the processing module is further used for acquiring the current limiting potential of the positive electrode of the target battery based on the positive electrode potential of the target battery under the condition that the current capacity loss change rate is not smaller than a first threshold value; and taking the improvement strategy as a current first charge-discharge strategy, and repeatedly executing the steps of executing a first number of charge-discharge operations on the target battery based on the first charge-discharge strategy; the improvement strategy includes: and stopping charging when the positive electrode potential of the target battery is not less than the current limit potential of the target battery.

10. An electronic device, comprising: a processor, and a memory communicatively coupled to the processor;

the memory stores computer-executable instructions;

the processor executes computer-executable instructions stored in the memory to implement the method of any one of claims 1-8.

11. A computer readable storage medium having stored therein computer executable instructions which when executed by a processor are adapted to carry out the method of any one of claims 1-8.