Charging control method and device, electronic equipment and storage medium

Abstract

The application provides a charging control method and device, electronic equipment and a storage medium. The method comprises: obtaining a turning point of conductivity when a battery is charged at a constant current, and obtaining a time corresponding to the turning point of conductivity; determining a first constant current charging duration according to a charging start time and the time corresponding to the turning point of conductivity, wherein a conductivity change rate corresponding to the turning point of conductivity is less than a preset conductivity change rate; controlling the battery to be charged at a first stage constant current with a first current when the first stage constant current charging is started, and controlling the battery to be charged at a second stage constant current with a second current when the first stage constant current charging duration is reached; and ending the charging of the battery when a charging end condition is reached. The method can solve the problem of how to control the efficient charging of a lithium ion battery while improving the safety of the battery charging and preventing the battery from overheating.

Description

Technical Field

[0001] This application relates to charging control technology, and more particularly to a charging control method, device, electronic device, and storage medium. Background Technology

[0002] As the market develops, consumers and businesses are demanding increasingly higher charging performance from lithium-ion batteries. The market needs lithium-ion batteries that can meet the requirements of high voltage, high capacity, high power, long lifespan, and high safety during charging. Correspondingly, the charging methods for lithium-ion batteries are also constantly evolving.

[0003] Currently, the main charging methods for lithium-ion batteries include constant current constant voltage (CCCV) charging, pulse charging, Relfex charging, and smart charging. For CCCV charging, in order to meet fast charging performance, the constant current charging current is usually increased to shorten the charging time. However, due to the internal resistance of the battery itself, high current charging will cause the battery to heat up, which is not conducive to the battery's performance and safety.

[0004] Therefore, how to control the efficient charging of lithium-ion batteries while improving the safety of battery charging and preventing overheating remains a problem to be solved. Summary of the Invention

[0005] This application provides a charging control method, apparatus, electronic device, and storage medium for controlling the efficient charging of lithium-ion batteries while improving battery charging safety and preventing battery overheating.

[0006] On the one hand, this application provides a charging control method, including:

[0007] The inflection point of the conductivity during constant current charging of the battery is obtained, and the time corresponding to the conductivity inflection point is obtained. The first constant current charging duration is determined based on the charging start time and the time corresponding to the conductivity inflection point, wherein the conductivity change rate corresponding to the conductivity inflection point is less than a preset conductivity change rate.

[0008] The battery is charged in the first stage using a first current to control the first stage of constant current charging. When the first constant current charging time is reached, the battery is charged in the second stage using a second current to control the second stage of constant current charging. The charging ends when the charging end condition is met.

[0009] In one embodiment, controlling the second stage of constant current charging of the battery with a second current until the charging termination condition is met, and ending the charging of the battery includes:

[0010] The second stage of constant current charging of the battery is controlled by the second current until the cutoff voltage is reached. Then, constant voltage charging of the battery is controlled until the cutoff current is reached, thus meeting the charging end condition and ending the charging of the battery.

[0011] The method further includes:

[0012] Obtain the threshold coefficient;

[0013] The cutoff current is determined based on the second current and the threshold coefficient.

[0014] In one embodiment, obtaining the threshold coefficient includes:

[0015] The upper limit voltage of the battery, the conductivity corresponding to the upper limit voltage, the doping ratio of silicon in the negative electrode material of the battery, the specific capacity of graphite in the battery, and the specific capacity of silicon in the battery are obtained, wherein the doping ratio is greater than zero and less than 50%.

[0016] A first value is obtained based on the second current, the doping ratio, and the specific capacity of silicon; a second value is obtained based on the upper charging voltage, the corresponding conductivity, the doping ratio, and the specific capacity of graphite.

[0017] The ratio of the first value to the second value is obtained as the threshold coefficient.

[0018] In one embodiment, the first-stage constant-current charging of the battery controlled by the first current includes:

[0019] When the initial conductivity of the battery before charging is less than the conductivity corresponding to the conductivity inflection point, the battery is charged with a first stage of constant current charging using a first current until the first constant current charging duration is reached.

[0020] In one embodiment, the method further includes:

[0021] When the initial conductivity is greater than or equal to the conductivity corresponding to the conductivity inflection point, the second stage of constant current charging of the battery with the second current is executed until the charging end condition is met, at which point the charging of the battery ends.

[0022] In one embodiment, the first current is greater than the second current, the first current ranges from 1.6 times to 3 times, the second current ranges from 0.5 times to 1 times, and the ratio between the cutoff current and the second current is 0.45.

[0023] On the other hand, this application provides a charging control device, including:

[0024] The acquisition module is used to acquire the inflection point of the conductivity during constant current charging of the battery, and to acquire the time corresponding to the conductivity inflection point. The first constant current charging duration is determined based on the charging start time and the time corresponding to the conductivity inflection point, wherein the conductivity change rate before the conductivity inflection point is greater than the conductivity change rate after the conductivity inflection point.

[0025] The charging control module is used to control the battery with a first current for the first stage of constant current charging. When the first constant current charging time is reached, the battery is controlled with a second current for the second stage of constant current charging. The charging ends when the charging end condition is met.

[0026] In one embodiment, the charging control module is specifically used for:

[0027] The second stage of constant current charging of the battery is controlled by the second current until the cutoff voltage is reached. Then, constant voltage charging of the battery is controlled until the cutoff current is reached, thus meeting the charging end condition and ending the charging of the battery.

[0028] The acquisition module is also used for:

[0029] Obtain the threshold coefficient;

[0030] The cutoff current is determined based on the second current and the threshold coefficient.

[0031] On the other hand, this application provides an electronic device, including: a processor, and a memory communicatively connected to the processor;

[0032] The memory stores computer-executed instructions;

[0033] The processor executes computer execution instructions stored in the memory to implement the charging control method as described in the first aspect.

[0034] On the other hand, this application provides a computer-readable storage medium storing computer-executable instructions that, when executed, cause a computer to perform the charging control method as described in the first aspect.

[0035] On the other hand, this application provides a computer program product, including a computer program that, when executed by a processor, implements the charging control method as described in the first aspect.

[0036] The method provided in the embodiments of this application includes: obtaining the inflection point of the battery's conductivity during constant current charging, obtaining the time corresponding to the conductivity inflection point, determining a first constant current charging duration based on the charging start time and the time corresponding to the conductivity inflection point, wherein the conductivity change rate corresponding to the conductivity inflection point is less than a preset conductivity change rate. A first stage of constant current charging of the battery is controlled using a first current and a first constant current charging duration. When the first constant current charging duration is reached, a second stage of constant current charging of the battery is controlled using a second current, until the charging termination condition is met, at which point the charging of the battery is terminated.

[0037] That is, firstly, based on the conductivity inflection point characteristics of the lithium-ion battery itself, the conductivity inflection point during charging is obtained. Since conductivity is related to battery temperature, the temperature change during battery charging can be monitored through conductivity. First, the time required to reach the conductivity inflection point is determined by the time corresponding to the conductivity inflection point and the charging start time, which is defined as the first constant current charging time.

[0038] After the conductivity inflection point, the battery charging rate decreases. Therefore, before the conductivity inflection point, the battery is charged with a first current. Once the first constant current charging period is reached, a second current is used to control the charging. In this way, as the battery charging rate decreases, a different current is used to control the charging, thus improving battery charging efficiency. By controlling the battery charging with different currents during the constant current charging stages, overheating can be prevented, improving battery charging safety. Attached Figure Description

[0039] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0040] Figure 1 A schematic diagram of an application scenario for the charging control method provided in this application;

[0041] Figure 2 A schematic flowchart of a charging control method provided in one embodiment of this application;

[0042] Figure 3 A schematic diagram of the charging state of a lithium-ion battery provided for one embodiment of this application;

[0043] Figure 4 A schematic diagram of a charging control device provided in one embodiment of this application;

[0044] Figure 5 A schematic diagram of an electronic device provided for one embodiment of this application.

[0045] The accompanying drawings have illustrated specific embodiments of this disclosure, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concepts of this disclosure to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0046] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0047] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0048] Currently, the main charging methods for lithium-ion batteries include constant current constant voltage (CCCV) charging, pulse charging, Relfex charging, and smart charging. For CCCV charging, in order to meet fast charging performance, the constant current charging current is usually increased to shorten the charging time. However, due to the internal resistance of the battery itself, high current charging will cause the battery to heat up, which is not conducive to the battery's performance and safety.

[0049] Existing battery charging control methods determine charging current and time by investigating the battery's temperature rise inflection point to suppress battery heating during charging. However, battery temperature is transferred from the inside out, and the temperature measured non-destructively may not match the actual internal temperature of the battery, which can affect the determination of constant current time. Some battery charging control methods use voltage zoning for constant current charging to activate battery capacity, but the heat generation issue in these methods needs to be effectively addressed.

[0050] Therefore, how to control the efficient charging of lithium-ion batteries while improving battery charging safety and preventing overheating remains a problem to be solved. Based on this, this application provides a charging control method, apparatus, electronic device, and storage medium. The charging control method obtains the inflection point of the battery's conductivity during constant current charging and the corresponding time. A first constant current charging duration is determined based on the charging start time and the time corresponding to the conductivity inflection point, wherein the conductivity change rate corresponding to the conductivity inflection point is less than a preset conductivity change rate. The first stage of constant current charging of the battery is controlled by a first current and the first constant current charging duration. When the first constant current charging duration is reached, a second current is used to control the second stage of constant current charging of the battery, until the charging termination condition is met, at which point the battery charging ends.

[0051] That is, firstly, based on the conductivity inflection point characteristics of the lithium-ion battery itself, the conductivity inflection point during charging is obtained. Since conductivity is related to battery temperature, the temperature change during battery charging can be monitored through conductivity. First, the time required to reach the conductivity inflection point is determined by the time corresponding to the conductivity inflection point and the charging start time, which is defined as the first constant current charging time.

[0052] After the conductivity inflection point, the battery charging rate decreases. Therefore, before the conductivity inflection point, the battery is charged with a first current. Once the first constant current charging period is reached, a second current is used to control the charging. In this way, as the battery charging rate decreases, a different current is used to control the charging, thus improving battery charging efficiency. By controlling the battery charging with different currents during the constant current charging stages, overheating can be prevented, improving battery charging safety.

[0053] The charging control method provided in this application is applied to electronic devices, such as controllers installed in terminal devices, controllers for remotely controlling terminal devices, etc., and the terminal devices include lithium-ion batteries. Figure 1 This is a schematic diagram illustrating the application of the charging control method provided in this application. In the diagram, the electronic device acquires the inflection point of the battery's conductivity during constant current charging and obtains the time corresponding to the conductivity inflection point. Based on the charging start time and the time corresponding to the conductivity inflection point, a first constant current charging duration is determined. The first stage of constant current charging of the lithium-ion battery is controlled using a first current and the first constant current charging duration. When the first constant current charging duration is reached, a second current is used to control the battery's second stage of constant current charging until the charging termination condition is met, at which point the battery charging is terminated.

[0054] Please see Figure 2 One embodiment of this application provides a charging control method, including:

[0055] S210, obtain the inflection point of the conductivity during constant current charging of the battery, and obtain the time corresponding to the conductivity inflection point. Determine the first constant current charging duration based on the charging start time and the time corresponding to the conductivity inflection point, wherein the conductivity change rate corresponding to the conductivity inflection point is less than the preset conductivity change rate.

[0056] It should be noted that the battery described in this embodiment is a lithium secondary battery with a conductivity inflection point during charging. The conductivity change rate corresponding to the conductivity inflection point is less than a preset conductivity change rate. At the conductivity inflection point σ TThe gradient of conductivity change is greater before the inflection point than after. Optionally, the battery contains a positive electrode, a negative electrode, a separator, and an electrolyte. The negative electrode contains an active coating that includes silicon-doped graphite material. The silicon dopant is one or more of silicon-carbon, silicon-oxygen, and other silicon compounds, and the graphite is one or more of commercially available synthetic graphite and natural graphite.

[0057] In an optional embodiment, the silicon doping ratio Z in the negative electrode material of the battery is less than fifty percent (50%).

[0058] As described above, changes in battery temperature during charging cause changes in conductivity. Conductivity is an internal characteristic of the battery and can be precisely monitored. Therefore, by adjusting the charging current based on the trend of conductivity changes, battery heat generation can be alleviated while charging quickly.

[0059] Tests revealed that during the constant current charging phase, there is an inflection point σ in the change of conductivity. T The rate of change of conductivity before the conductivity inflection point is greater than the rate of change of conductivity after the conductivity inflection point. Therefore, by adopting different charging strategies before and after the conductivity inflection point, efficient battery charging can be achieved.

[0060] Specifically, before the conductivity inflection point, the battery is charged at a constant current using a first current; after the conductivity inflection point, the battery is charged at a constant current using a second current. Optionally, the first current is greater than the second current, thus ensuring efficient charging of the battery after the conductivity inflection point while preventing excessive overheating of the lithium-ion battery.

[0061] When controlling the battery with a first current for constant current charging, the duration of the first constant current charging needs to be known. Specifically, the inflection point of the battery's conductivity during constant current charging is obtained, and the time corresponding to the conductivity inflection point is also obtained. The duration from the start of charging to the time corresponding to the conductivity inflection point is determined as the first constant current charging duration.

[0062] S220: The battery is charged in the first stage by a first current. When the first constant current charging time is reached, the battery is charged in the second stage by a second current. The charging ends when the charging end condition is met.

[0063] That is, when charging the battery begins, a first current I1 is used for constant current charging for the first constant current charging duration. After the first constant current charging duration is reached, a second current I2 is used for constant current charging until the charging termination condition is met. Preferably, the value of the first current I1 ranges from 1.6 times the current rate (C) to 3C, and the value of the second current I2 ranges from 0.5C to 1C.

[0064] The battery is charged in the second stage using a second current-controlled constant current until the cutoff voltage Vx is reached. Then, the battery is charged at a constant voltage until the cutoff current Ix is reached, thus ending the charging process. It should be noted that the charging current continuously decreases during constant voltage charging, and charging ends when the current decreases to the cutoff current.

[0065] like Figure 3 The diagram illustrates the changes in charging current, charging voltage, and battery conductivity over time (horizontal axis) when the charging control method provided in this embodiment is used to control battery charging. As shown, during the first constant current charging duration t1, the battery is controlled to perform constant current charging with a first current I1, and both the charging voltage and conductivity continuously increase. At the end of the first constant current charging duration t1, the battery is controlled to perform constant current charging with a second current I2. At this point, a turning point in conductivity growth occurs (i.e., the conductivity turning point), and the conductivity begins to increase slowly, while the charging voltage continues to increase. When the charging voltage reaches the preset voltage Vx, constant voltage charging begins, at which point the conductivity and charging current continuously decrease. When the charging current of constant voltage charging is less than the cutoff current, constant voltage charging ends, and the battery charging current continuously decreases until the battery charging current reaches 0, at which point charging is completely finished.

[0066] During the constant voltage charging stage, the constant voltage charging time is shortened by setting the cutoff current Ix, thereby mitigating the side reactions that occur in lithium-ion batteries under high voltage.

[0067] In an optional embodiment, the cutoff current Ix is determined based on the second current. Specifically, a threshold coefficient is obtained, and the cutoff current is determined based on the second current and the threshold coefficient. Ix = I² × K, where K represents the threshold coefficient and I² represents the second current.

[0068] The threshold coefficient K is determined based on the charging characteristics of the battery. Specifically, the upper limit voltage (Vx) of the battery, the conductivity (σ) corresponding to the upper limit voltage, the silicon doping ratio (Z) in the negative electrode material of the battery, the specific capacity of graphite (B) in the battery, and the specific capacity of silicon in the battery (A) are obtained.

[0069] A first value is obtained based on the second current I2, the doping ratio Z, and the specific capacity A of the silicon; this first value is I2 × Z × A. A second value is obtained based on the upper charging voltage Vx, the corresponding conductivity σ, the doping ratio Z, and the specific capacity B of the graphite; this second value is σ × Vx × (1-Z) × B. Finally, the ratio of the first value to the second value is taken as the threshold coefficient, i.e., K = I2 × Z × A / σ × Vx × (1-Z) × B.

[0070] In an optional embodiment, battery charging is not controlled sequentially according to the order of the first stage constant current charging and the second stage constant current charging. Instead, the battery is charged with the first stage constant current charging only when the initial conductivity before charging is lower than the conductivity corresponding to the conductivity inflection point, until the first constant current charging duration is reached. Then, the lithium-ion battery is charged with the second stage constant current charging with the second current until a preset voltage is reached, at which point the lithium-ion battery is charged with the preset voltage as a constant voltage. When the charging current of the constant voltage charging is lower than the cutoff current, the charging of the lithium-ion battery ends.

[0071] When the initial conductivity is greater than or equal to the conductivity at the inflection point, the second stage of constant current charging is initiated directly. This involves executing the second stage of constant current charging, controlled by a second current, until the charging termination condition is met, at which point the charging process ends. This avoids the first stage of constant current charging if the battery's initial conductivity is too high, preventing overheating due to prolonged charging and avoiding low charging efficiency. Different charging strategies are implemented based on the actual charging status of the battery to improve charging efficiency and prevent overheating.

[0072] Table 1 shows five embodiments of controlling battery charging using the method provided in this embodiment. Table 1 includes the battery capacity retention rate and battery temperature change obtained after changing the first current, the second current and the cutoff current and performing experimental cycles (300 cycles in Table 1).

[0073] Table 1:

[0074]

[0075] As shown in Table 1, using I1, I2, and Ix from Example 1 to control battery charging, after 300 cycles, the lithium-ion battery retained 94% of its capacity, with a temperature change of 15°C, thus extending its cycle life. The lithium-ion battery in Example 2 retained 91% of its capacity, with a temperature change of 18°C, meeting the cycle requirements for lithium-ion batteries. The lithium-ion battery in Example 3 retained 82% of its capacity, with a temperature change of 24°C. Although the charging speed was accelerated, the cycle performance was only average after 300 cycles. The lithium-ion battery in Example 4 retained 60% of its capacity, with a temperature change of 17°C. This was due to the excessively long constant-voltage charging time, which gradually consumed the limited lithium and caused severe side reactions. The capacity retention rate of the lithium-ion battery corresponding to Example 5 was 47%, and the battery temperature change was 31°C. This is because the current needs to be reduced to 0 during constant voltage charging, and a high-rate current I2 is used for charging during constant current charging. Although this speeds up the charging speed of the lithium-ion battery, the cycle performance of the lithium-ion battery is found to be poor after 300 cycles.

[0076] Therefore, when controlling lithium-ion battery charging using the method provided in this embodiment, the first current ranges from 1.6C to 3C, the second current ranges from 0.5C to 1C, and the ratio between the cutoff current Ix and the second current I2 is 0.45. This maintains a high capacity retention rate for the lithium-ion battery, reduces temperature changes during charging, controls efficient charging while preventing overheating, and extends the battery's lifespan.

[0077] In summary, the charging control method provided in this embodiment first obtains the conductivity inflection point of the lithium-ion battery during charging based on the conductivity inflection characteristics of the lithium-ion battery itself. Since conductivity is related to battery temperature, temperature changes during battery charging can be monitored through conductivity. First, the time required to reach the conductivity inflection point is determined by the time corresponding to the conductivity inflection point and the charging start time, which is then defined as the first constant current charging time.

[0078] After the conductivity inflection point, the battery charging rate decreases. Therefore, before the conductivity inflection point, the battery is charged with a first current. Once the first constant current charging period is reached, a second current is used to control the charging. In this way, as the battery charging rate decreases, a different current is used to control the charging, thus improving battery charging efficiency. By controlling the battery charging with different currents during the constant current charging stages, overheating can be prevented, improving battery charging safety.

[0079] Therefore, the charging control method provided in this embodiment can not only control the efficient charging of lithium-ion batteries, but also improve the safety of battery charging and prevent battery overheating.

[0080] Please see Figure 4 One embodiment of this application also provides a charging control device 10, comprising:

[0081] The acquisition module 11 is used to acquire the inflection point of the conductivity during constant current charging of the battery, and to acquire the time corresponding to the conductivity inflection point. The first constant current charging duration is determined based on the charging start time and the time corresponding to the conductivity inflection point, wherein the conductivity change rate before the conductivity inflection point is greater than the conductivity change rate after the conductivity inflection point.

[0082] The charging control module 12 is used to control the first stage of constant current charging of the battery with a first current, and when the first constant current charging time is reached, to control the second stage of constant current charging of the battery with a second current, until the charging end condition is met, and then to end the charging of the battery.

[0083] The charging control module 12 is specifically used to control the second stage of constant current charging of the battery with a second current until the cutoff voltage is reached, then control the battery to charge at a constant voltage until the cutoff current is reached, thus meeting the charging end condition and ending the charging of the battery.

[0084] The acquisition module 11 is also used to acquire a threshold coefficient; and to determine the cutoff current based on the second current and the threshold coefficient.

[0085] The acquisition module 11 is specifically used to acquire the upper limit charging voltage of the battery, the conductivity corresponding to the upper limit charging voltage, the doping ratio of silicon in the negative electrode material of the battery, the specific capacity of graphite in the battery, and the specific capacity of silicon in the battery, wherein the doping ratio is greater than zero and less than 50%; to obtain a first value based on the second current, the doping ratio, and the specific capacity of silicon; to obtain a second value based on the upper limit charging voltage, the corresponding conductivity, the doping ratio, and the specific capacity of graphite; and to obtain the ratio of the first value and the second value as the threshold coefficient.

[0086] The charging control module 12 is specifically used to control the battery to perform a first stage of constant current charging with a first current when the initial conductivity of the battery before charging is less than the conductivity corresponding to the conductivity inflection point, until the first constant current charging duration is reached.

[0087] The charging control module 12 is further configured to execute the step of controlling the battery with a second current in the second stage of constant current charging when the initial conductivity is greater than or equal to the conductivity corresponding to the conductivity inflection point, until the charging end condition is met, and then end the charging of the battery. The first current is greater than the second current, the first current ranges from 1.6 times to 3 times the initial conductivity, the second current ranges from 0.5 times to 1 times the initial conductivity, and the ratio between the cutoff current and the second current is 0.45.

[0088] Please see Figure 5 One embodiment of this application also provides an electronic device 20, including a processor 21 and a memory 22 communicatively connected to the processor 21. The memory 22 stores computer-executable instructions. The processor 21 executes the computer-executable instructions stored in the memory to implement the charging control method provided in any of the above embodiments.

[0089] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed, cause the computer-executable instructions to be executed by a processor to implement the charging control method provided in any of the preceding embodiments.

[0090] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the charging control method as provided in any of the preceding embodiments.

[0091] It should be noted that the aforementioned computer-readable storage media can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic random access memory (FRAM), flash memory, magnetic surface memory, optical disc, or compact disc read-only memory (CD-ROM), etc. It can also be various electronic devices that include one or any combination of the above-mentioned memories, such as mobile phones, computers, tablet devices, personal digital assistants, etc.

[0092] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0093] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0094] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0095] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0096] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0097] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0098] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A charge control method characterized by, include: The inflection point of conductivity during constant current charging of the battery is obtained, and the time corresponding to the conductivity inflection point is obtained. The first constant current charging duration is determined based on the charging start time and the time corresponding to the conductivity inflection point. The conductivity inflection point is the inflection point where the rate of change of conductivity changes from large to small during constant current charging, and the rate of change of conductivity corresponding to the conductivity inflection point is less than a preset rate of change of conductivity. The battery is charged in the first stage using a first current to control the first stage of constant current charging. When the first constant current charging time is reached, the battery is charged in the second stage using a second current to control the second stage of constant current charging. The charging process continues until the charging end condition is met, at which point the charging process ends.

2. The method of claim 1, wherein, The second stage of constant current charging of the battery is controlled by a second current until the charging termination condition is met. The charging process then terminates, including: The second stage of constant current charging of the battery is controlled by the second current until the cutoff voltage is reached. Then, constant voltage charging of the battery is controlled until the cutoff current is reached, thus meeting the charging end condition and ending the charging of the battery. The method further includes: Obtain the threshold coefficient; The cutoff current is determined based on the second current and the threshold coefficient.

3. The method according to claim 2, characterized in that, The threshold coefficients obtained include: The upper limit voltage of the battery, the conductivity corresponding to the upper limit voltage, the doping ratio of silicon in the negative electrode material of the battery, the specific capacity of graphite in the battery, and the specific capacity of silicon in the battery are obtained, wherein the doping ratio is greater than zero and less than 50%. A first value is obtained based on the second current, the doping ratio, and the specific capacity of silicon; a second value is obtained based on the upper charging voltage, the corresponding conductivity, the doping ratio, and the specific capacity of graphite. The ratio of the first value to the second value is obtained as the threshold coefficient.

4. The method according to any one of claims 1 to 3, characterized in that, The first stage of constant current charging of the battery controlled by the first current includes: When the initial conductivity of the battery before charging is less than the conductivity corresponding to the conductivity inflection point, the battery is charged with a first stage of constant current charging using a first current until the first constant current charging duration is reached.

5. The method of claim 4, wherein, The method further includes: When the initial conductivity is greater than or equal to the conductivity corresponding to the conductivity inflection point, the second stage of constant current charging of the battery with the second current is executed until the charging end condition is met, at which point the charging of the battery ends.

6. The method according to any one of claims 1 to 3, characterized in that, The first current is greater than the second current. When the value range of the first current is 1.6 times to 3 times, the value range of the second current is 0.5 times to 1 times, and the ratio between the cutoff current and the second current is 0.

45.

7. A charge control device, characterized by comprising: include: The acquisition module is used to acquire the inflection point of conductivity during constant current charging of the battery, and to acquire the time corresponding to the conductivity inflection point. The first constant current charging duration is determined based on the charging start time and the time corresponding to the conductivity inflection point. The conductivity inflection point is the inflection point where the rate of change of conductivity changes from large to small during constant current charging, and the rate of change of conductivity before the conductivity inflection point is greater than the rate of change of conductivity after the conductivity inflection point. The charging control module is used to control the battery with a first current for the first stage of constant current charging. When the first constant current charging time is reached, the battery is controlled with a second current for the second stage of constant current charging. The charging ends when the charging end condition is met.

8. The charge control device according to claim 7, characterized by The charging control module is specifically used for: The second stage of constant current charging of the battery is controlled by the second current until the cutoff voltage is reached. Then, constant voltage charging of the battery is controlled until the cutoff current is reached, thus meeting the charging end condition and ending the charging of the battery. The acquisition module is also used for: Obtain the threshold coefficient; The cutoff current is determined based on the second current and the threshold coefficient.

9. An electronic device, comprising: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the charging control method as described in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions that, when executed, cause the computer to perform the charging control method as described in any one of claims 1-6.

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