Method and device for determining charging duration, electronic equipment and storage medium

Abstract

This application provides a method, apparatus, electronic device, and storage medium for determining charging time. The method includes: obtaining a target charging rate; controlling the battery to perform constant current charging at the target charging rate; and obtaining parameter information during the battery charging process. When the battery is determined to be at a lithium plating critical point based on the parameter information, the method obtains the charging time at the lithium plating critical point, and uses the charging time at the lithium plating critical point as the target charging time for the target charging rate, wherein the lithium plating critical point represents a state point where the battery is about to plating lithium but has not yet done so. This method can solve the problem of how to improve the charging mechanism of lithium-ion batteries, so that when controlling the charging of lithium-ion batteries by charging rate, the charging time at each rate can be effectively controlled to avoid lithium plating, while simultaneously achieving fast charging.

Description

Technical Field

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

[0002] Lithium-ion batteries possess advantages such as high voltage, large specific capacity, low self-discharge, long cycle life, and no memory effect among rechargeable batteries, making them the best type of rechargeable battery for portable electronic devices and electric vehicles. However, lithium-ion batteries also have the disadvantage of lithium plating, posing certain safety issues during use. Therefore, it is essential to scientifically and effectively control battery parameters and design appropriate charging strategies during lithium battery operation to ensure safe and efficient battery operation.

[0003] To date, there are still many problems with lithium-ion battery charging, such as the common lithium plating issue. Lithium plating in lithium-ion batteries has many causes, the most common being improper charging mechanisms, such as the inability to effectively control the charging time at a certain high rate, thus leading to lithium plating.

[0004] Improving the charging mechanism of lithium-ion batteries to effectively control the charging time at each charging rate to avoid lithium plating while achieving fast charging remains an urgent problem to be solved. Summary of the Invention

[0005] This application provides a method, apparatus, electronic device, and storage medium for determining charging time, in order to solve the problem of how to improve the charging mechanism of lithium-ion batteries, so that when controlling the charging of lithium-ion batteries by charging rate, the charging time at each rate can be effectively controlled to avoid lithium plating, while achieving fast charging of the battery.

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

[0007] Obtain the target charging rate, control the battery to perform constant current charging at the target charging rate, and obtain parameter information during the battery charging process;

[0008] When the battery is determined to be at the lithium plating critical point based on the parameter information, the charging time when the battery is at the lithium plating critical point is obtained, and the charging time when the battery is at the lithium plating critical point is taken as the target charging time of the target charging rate, wherein the lithium plating critical point represents the state point where the battery is about to plating lithium but has not yet plating lithium.

[0009] In one embodiment, the parameter information includes at least one or more of the following sets of information: the first set of information includes the real-time thickness of the battery and the real-time capacity of the battery; the second set of information includes the real-time voltage of the battery and the real-time capacity of the battery; the third set of information includes the real-time conductivity of the battery; and the fourth set of information includes the negative electrode surface density of the battery.

[0010] Determining that the battery is at the lithium plating critical point based on the parameter information includes:

[0011] A first characteristic curve of the battery is constructed based on the real-time thickness and real-time capacity of the battery. When an abnormal inflection point appears on the first characteristic curve, the battery is determined to be at the lithium plating critical point when the real-time thickness of the battery corresponds to the thickness of the abnormal inflection point; and / or,

[0012] A second characteristic curve for the battery is constructed based on its real-time voltage and real-time capacity. When an abnormal inflection point appears on the second characteristic curve, the battery is determined to be at the lithium plating critical point when its real-time voltage corresponds to that abnormal inflection point; and / or,

[0013] A third characteristic curve of the battery is constructed based on its real-time conductivity and charging time. When an abnormal inflection point appears on the third characteristic curve, the real-time conductivity of the battery is determined to be the conductivity corresponding to the abnormal inflection point, indicating that the battery is at the lithium plating critical point; and / or,

[0014] When the surface density of the negative electrode of the battery is equal to the preset surface density of the negative electrode, the battery is determined to be at the lithium plating critical point.

[0015] In one embodiment, when an abnormal inflection point appears on the first characteristic curve, determining that the real-time thickness of the battery is the thickness corresponding to the abnormal inflection point indicates that the battery is at the lithium plating critical point includes:

[0016] A first reference feature curve is obtained, which is constructed based on the reference real-time thickness and reference real-time capacity of the battery during charging. The reference real-time thickness and reference real-time capacity are obtained when the battery is charged with a preset charging rate and no lithium plating occurs.

[0017] When the first reference feature curve and the first feature curve are different, it is determined that the first feature curve has an abnormal inflection point, and when it is determined that the real-time thickness of the battery is the thickness corresponding to the abnormal inflection point, the battery is at the lithium plating critical point.

[0018] In one embodiment, when the second characteristic curve shows an abnormal inflection point, determining that the real-time voltage of the battery is the voltage corresponding to the abnormal inflection point indicates that the battery is at the lithium plating critical point includes:

[0019] A second reference characteristic curve is obtained, which is constructed based on the reference real-time voltage and reference real-time capacity when the battery is charging. The reference real-time voltage and reference real-time capacity are obtained when the battery is charged at a preset charging rate and no lithium plating occurs.

[0020] When the second reference characteristic curve and the second characteristic curve are different, it is determined that the second characteristic curve has an abnormal inflection point, and when it is determined that the real-time voltage of the battery is the voltage corresponding to the abnormal inflection point, the battery is at the lithium plating critical point.

[0021] In one embodiment, the method further includes:

[0022] Obtain multiple preset target charging rates and the target charging time corresponding to each target charging rate;

[0023] Based on each target charging rate and the corresponding target charging duration, target charging data for the battery at the specified charging rate is determined, so as to enable the battery to be charged according to the target charging data.

[0024] In one embodiment, the method further includes:

[0025] The battery is controlled to perform constant current charging based on the target charging data;

[0026] When the real-time voltage of the battery reaches the preset voltage, the battery is controlled to perform constant voltage charging until the real-time charging capacity of the battery reaches the preset charging capacity, at which point the charging of the battery is stopped.

[0027] In one embodiment, controlling the battery to perform constant current charging based on the target charging data includes:

[0028] Multiple target charging rates are sorted according to the magnitude of each target charging rate. The sorting result includes Z target charging rates arranged from smallest to largest, where the Zth target charging rate is the largest charging rate among the multiple target charging rates, and Z is a natural number greater than 1.

[0029] The battery is controlled to perform constant current charging based on the Zth target charging rate and the Zth target charging time corresponding to the Zth target charging rate.

[0030] Decrease Z by 1, and repeat the step described above, controlling the battery to perform constant current charging with the Zth target charging rate and the Zth target charging time corresponding to the Zth target charging rate, until the real-time voltage of the battery reaches the preset voltage.

[0031] On the other hand, this application provides a device for determining charging time, comprising:

[0032] The acquisition module is used to obtain the target charging rate;

[0033] The control module is used to control the battery to perform constant current charging at the target charging rate;

[0034] The acquisition module is also used to acquire parameter information during the battery charging process;

[0035] The acquisition module is further configured to, when the battery is determined to be at the lithium plating critical point based on the parameter information, acquire the charging time when the battery is at the lithium plating critical point, and use the charging time when the battery is at the lithium plating critical point as the target charging time of the target charging rate, wherein the lithium plating critical point represents the state point where the battery is about to plating lithium but has not yet plating lithium.

[0036] On the other hand, this application provides an electronic device, including: a processor, and a memory communicatively connected to the processor;

[0037] The memory stores computer-executed instructions;

[0038] The processor executes computer execution instructions stored in the memory to implement the method for determining the charging time as described in the first aspect.

[0039] 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 method for determining charging duration as described in the first aspect.

[0040] On the other hand, this application provides a computer program product, including a computer program that, when executed by a processor, implements the method for determining charging time as described in the first aspect.

[0041] In summary, embodiments of this application provide a method for determining charging time. This method includes: obtaining a target charging rate; controlling the battery to perform constant current charging at the target charging rate; and obtaining parameter information during the battery charging process. When the battery is determined to be at a lithium plating critical point based on the parameter information, the method obtains the charging time at the lithium plating critical point, and uses the charging time at the lithium plating critical point as the target charging time for the target charging rate. The lithium plating critical point represents a state point where the battery is about to plating lithium but has not yet plating lithium.

[0042] That is, before controlling the battery charging rate, the target charging time for a specific target charging rate in the charging data is first determined. The target charging time is determined by controlling the battery to perform constant current charging at the target charging rate and acquiring the parameter information during the charging process. Then, based on this parameter information, it is determined whether lithium plating is imminent during battery charging. If lithium plating is about to occur, the point at which lithium plating is about to occur is determined as the limit time point for controlling battery charging at the target charging rate, and the corresponding charging time is the limit time for controlling battery charging at the target charging rate (target charging time). Thus, before controlling the battery charging rate, the target charging time for each charging rate can be determined according to this method, thereby controlling the battery to prevent lithium plating while achieving rapid charging. Therefore, the charging time determination method provided in this application can solve the problem of how to improve the charging mechanism of lithium-ion batteries, so that when controlling lithium-ion battery charging by charging rate, the charging time at each rate can be effectively controlled to avoid lithium plating while achieving rapid battery charging. Attached Figure Description

[0043] 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.

[0044] Figure 1 A schematic diagram illustrating an application scenario of the method for determining charging duration provided in this application;

[0045] Figure 2 A flowchart illustrating a method for determining charging time according to an embodiment of this application;

[0046] Figure 3 A schematic diagram of an abnormal turning point in a method for determining charging time provided in an embodiment of this application;

[0047] Figure 4 A schematic diagram of an abnormal turning point in a method for determining charging duration provided in another embodiment of this application;

[0048] Figure 5 A schematic diagram of an abnormal turning point in a method for determining charging time provided in another embodiment of this application;

[0049] Figure 6 A schematic diagram of a charging duration determination device provided in one embodiment of this application;

[0050] Figure 7 A schematic diagram of an electronic device provided for one embodiment of this application.

[0051] 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

[0052] 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.

[0053] 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.

[0054] Lithium plating in lithium-ion batteries is a very common anomaly in the lithium battery industry. Common causes include improper charging mechanisms, which can be further categorized as low-temperature charging plating, high-rate charging plating, and overcharging plating. High-rate charging plating occurs when the charging rate is continuously increased at room temperature, preventing the negative electrode of the lithium-ion battery from quickly completing lithium intercalation, thus triggering plating. Another cause is the inability to effectively control the charging time at a high rate, leading to lithium plating.

[0055] Improving the charging mechanism of lithium-ion batteries to effectively control the charging time at each charging rate to avoid lithium plating while achieving fast charging remains an urgent problem to be solved.

[0056] Based on this, this application provides a method, apparatus, electronic device, and storage medium for determining charging time. The method for determining charging time includes: obtaining a target charging rate, controlling the battery to perform constant current charging at the target charging rate, and obtaining parameter information during the battery charging process; when it is determined from the parameter information that the battery is at a lithium plating critical point, obtaining the charging time at the lithium plating critical point, and using the charging time at the lithium plating critical point as the target charging time for the target charging rate, wherein the lithium plating critical point represents the state point where the battery is about to plating lithium but has not yet plating lithium.

[0057] In other words, before controlling the battery charging rate, the target charging time for a specific target charging rate in the charging data is first determined. The target charging time is determined by controlling the battery to perform constant current charging at the target charging rate and acquiring the parameter information during the charging process. Then, based on this parameter information, it is determined whether lithium plating has occurred during the charging process. If lithium plating is imminent but has not yet occurred (i.e., critical lithium plating), the critical lithium plating time point is determined as the limit time point for controlling battery charging at the target charging rate, and the corresponding charging time is the limit time for controlling battery charging at the target charging rate (target charging time). Thus, before controlling the battery charging rate, the target charging time for each charging rate can be determined according to this method, thereby controlling the battery to prevent lithium plating while achieving rapid charging. Therefore, the charging time determination method provided in this application can solve the problem of how to improve the charging mechanism of lithium-ion batteries, so that when controlling lithium-ion battery charging by charging rate, the charging time at each rate can be effectively controlled to avoid lithium plating while achieving rapid battery charging.

[0058] The method for determining charging time 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 contain lithium-ion batteries. Figure 1 This diagram illustrates the application of the charging rate determination method provided in this application. In the diagram, the electronic device acquires a target charging rate, controls the battery to perform constant current charging at the target charging rate, and acquires parameter information during the battery charging process. When the parameter information determines that the battery is at the lithium plating critical point, the charging time at the lithium plating critical point is acquired, and this charging time is taken as the target charging time for the target charging rate.

[0059] Please see Figure 2 An embodiment of this application also provides a method for determining charging time, including:

[0060] S210: Obtain the target charging rate, control the battery to perform constant current charging at the target charging rate, and obtain parameter information during the battery charging process.

[0061] The target charging rate refers to the charging rate (i.e., the rate of charging current) during a certain constant current charging stage when controlling the battery to perform high-rate charging. For example, if there are three constant current charging stages when controlling the battery to perform high-rate charging, then there are three target charging rates that need to be determined for the target charging time.

[0062] During the process of controlling the battery to undergo constant current charging at the target charging rate, it is necessary to acquire parameter information of the battery during the charging process. This parameter information includes, for example, the battery's real-time capacity, real-time voltage, real-time thickness, real-time conductivity, and negative electrode surface density, which are used to determine the lithium plating critical point during the battery charging process.

[0063] In an optional embodiment, the parameter information includes at least one or more of the following sets of information: the first set of information includes the real-time thickness and real-time capacity of the battery; the second set of information includes the real-time voltage and real-time capacity of the battery; the third set of information includes the real-time conductivity of the battery; and the fourth set of information includes the negative electrode surface density of the battery.

[0064] When determining that the battery is at the lithium plating critical point based on the first set of information, a first characteristic curve of the battery can be constructed based on its real-time thickness and real-time capacity. When an abnormal inflection point appears on the first characteristic curve, and the real-time thickness of the battery is determined to be the thickness corresponding to the abnormal inflection point, the battery is at the lithium plating critical point. Alternatively, when an abnormal inflection point appears on the first characteristic curve, and the real-time capacity of the battery is determined to be the capacity corresponding to the abnormal inflection point, the battery is at the lithium plating critical point. It should be noted that when the battery is not undergoing lithium plating, its real-time thickness increases slowly with the increase in its real-time capacity. The increase in battery thickness is only related to the amount of charge applied and is not affected by the charging rate. When the battery undergoes lithium plating, the thickness of the battery cells increases abnormally rapidly, causing a sudden change in the battery voltage, which is also very obvious on the first characteristic curve. Specifically, when the battery undergoes lithium plating, an abnormal inflection point will appear on the first characteristic curve. That is, when an abnormal inflection point appears on the first characteristic curve, lithium plating is determined, and the abnormal inflection point corresponds to the lithium plating critical point. Please refer to [link to relevant documentation]. Figure 3 Optionally, a first reference characteristic curve can also be obtained. Figure 3 Curve 1 in the middle), when the first reference characteristic curve and the first characteristic curve ( Figure 3 When curve 2) is different from the first characteristic curve, determine the abnormal inflection point of the first characteristic curve (e.g., Figure 3 Chinese MThe first reference characteristic curve is constructed based on the reference real-time thickness and reference real-time capacity of the battery during charging. These reference real-time thickness and capacity are obtained when the battery is charged at a preset charging rate and lithium plating has not occurred. As described above, the increase in battery thickness is only related to the amount of charge applied and is not affected by the charging rate. Therefore, when the battery has not plating lithium, the first characteristic curve and the first reference characteristic curve should be the same. Therefore, when the first reference characteristic curve and the first characteristic curve are different, an abnormal inflection point is determined in the first characteristic curve, thereby determining the lithium plating critical point of the battery. Optionally, the preset charging rate is 0.1C.

[0065] When determining that the battery is at the lithium plating critical point based on the second set of information, a second characteristic curve for the battery is constructed based on its real-time voltage and real-time capacity. When an abnormal inflection point appears on the second characteristic curve, the battery is considered to be at the lithium plating critical point when the real-time voltage corresponds to that inflection point. Alternatively, the battery is considered to be at the lithium plating critical point when the real-time capacity corresponds to that inflection point. It should be noted that when the battery is not undergoing lithium plating, its voltage increases with increasing charging time and charging capacity, and this voltage increase is unaffected by the charging rate. However, when lithium plating occurs, it causes a sudden change in the battery voltage, resulting in an abnormal inflection point on the second characteristic curve. This abnormal inflection point corresponds to the lithium plating critical point. Therefore, when an abnormal inflection point appears on the second characteristic curve, the lithium plating critical point of the battery can be determined. Please refer to [link to relevant documentation]. Figure 4 Optionally, obtain the second reference characteristic curve. Figure 4 Curve 1 in the middle), when the second reference characteristic curve ( Figure 4 Curve 1) and the second characteristic curve ( Figure 4 When curve 2) is different from the second characteristic curve, determine the abnormal inflection point of the second characteristic curve (e.g. Figure 4 Chinese M (Corresponding to the marked points), and determine the lithium plating of the battery. The second reference characteristic curve is constructed based on the reference real-time voltage and reference real-time capacity of the battery during charging, which are obtained when charging at a preset charging rate and without lithium plating. As described above, the voltage increase of the battery is not affected by the charging rate, so when the battery is not undergoing lithium plating, the trend of the second characteristic curve and the trend of the second reference characteristic curve should be the same. Therefore, when the trend of the second reference characteristic curve and the trend of the second characteristic curve are different, it is determined that the second characteristic curve has an abnormal inflection point, and thus the lithium plating critical point of the battery can be determined. Optionally, the preset charging rate is 0.1C.

[0066] In an optional embodiment, the lithium plating critical point of the battery can also be determined based on the battery's real-time conductivity and charging time. Specifically, a third characteristic curve of the battery is constructed based on its real-time conductivity and charging time. When the battery is not undergoing lithium plating, its conductivity increases with increasing charging time. However, when lithium plating occurs, it causes a sudden change in the battery's conductivity, resulting in an abnormal inflection point on the third characteristic curve. When an abnormal inflection point appears on the third characteristic curve, and the real-time conductivity of the battery is determined to be the conductivity corresponding to the abnormal inflection point, the battery is at the lithium plating critical point. Please refer to [link to previous text]. Figure 5 Optionally, a reference conductivity can be obtained when the battery is charged to a preset charging capacity without lithium plating, and a third reference characteristic curve can be constructed based on the reference conductivity and charging time. Figure 5 Curve 1 in the middle). Then compare this third reference characteristic curve ( Figure 5 Curve 1) and the third characteristic curve ( Figure 5 (2) When the third reference characteristic curve and the third characteristic curve are different, an abnormal inflection point is determined for the third characteristic curve (e.g., curve 2). Figure 5 Chinese M The corresponding marked points are used to determine the lithium plating critical point of the battery. When no abnormal inflection point appears on the third characteristic curve, it is determined that the battery has not undergone lithium plating during the charging process.

[0067] In an optional embodiment, the battery is determined to be at a lithium plating critical point when the negative electrode isal density equals a preset negative electrode isal density. This preset negative electrode isal density refers to the maximum negative electrode isal density of the battery determined based on its material properties. If the negative electrode isal density measured during charging exceeds the maximum negative electrode isal density, it indicates lithium plating during charging, leading to a significant change in the battery's material properties. That is, after the lithium plating critical point, the negative electrode isal density will be greater than the preset isal density. Therefore, the lithium plating critical point can be determined by comparing the current negative electrode isal density with the preset negative electrode isal density.

[0068] When determining the lithium plating critical point of the battery, the critical point can be determined by combining the first, second, third, and fourth sets of information, or by using one set of information, any two sets of information, or any three sets of information. Preferably, to ensure the accuracy of the determined lithium plating critical point, the critical point is determined by combining the first, second, third, and fourth sets of information.

[0069] This parameter information can also include other information, as long as it can be used to determine whether the battery has undergone lithium plating and to determine the lithium plating critical point of the battery. This embodiment only describes a few methods for determining whether the battery has undergone lithium plating and to determine the lithium plating critical point of the battery. In practice, other methods can also be used to determine whether the battery has undergone lithium plating, and this embodiment does not limit them.

[0070] S220, when it is determined that the battery is at the lithium plating critical point based on the parameter information, the charging time when the battery is at the lithium plating critical point is obtained, and the charging time when the battery is at the lithium plating critical point is taken as the target charging time of the target charging rate, wherein the lithium plating critical point represents the state point where the battery is about to plating lithium but has not yet plating lithium.

[0071] If the parameter information indicates that the battery has not yet deposited lithium, it means that the maximum charging time at the target charging rate has not been reached. This maximum charging time refers to the charging time required for the battery to reach the maximum state of no lithium deposit. The purpose of this embodiment is to determine the maximum charging time at the target charging rate; therefore, it is necessary to determine the maximum charging time at the target charging rate based on the time it takes for the battery to be about to deposit lithium but has not yet done so.

[0072] Taking the first set of information and the second set of information as examples, when obtaining the charging time when the battery is at the lithium plating critical point, the charging time is determined based on the moment when an abnormal inflection point appears on the first characteristic curve or the second characteristic curve. Specifically, by comparing the first characteristic curve and the first reference characteristic curve, the time when the two characteristic curves differ is obtained, and the target charging time for the target charging rate can be determined based on the time when the difference occurs. Alternatively, by comparing the second characteristic curve and the second reference characteristic curve, the time when the two characteristic curves differ is obtained, and the target charging time for the target charging rate can be determined based on the time when the difference occurs.

[0073] For example, the target charging rate is 0.5C. The battery is controlled to charge at a 0.5C rate, and a first or second characteristic curve is constructed for different constant current charging times, including 1 minute (min), 2 minutes, 3 minutes, 4 minutes, 5 minutes, ..., 120 minutes. The preset charging rate is 0.1C. The battery is controlled to charge at a 0.1C rate for at least 120 minutes, and a first or second reference characteristic curve corresponding to this preset charging rate is constructed. If, when the battery is charged at a 0.5C rate, the first characteristic curve shows an abnormal inflection point when the charging time reaches 100 minutes, then the target charging time for the 0.5C rate is determined to be 100 minutes.

[0074] For example, if the target charging rate is 1C, the battery is controlled to charge at a 1C rate, and a first characteristic curve or a second characteristic curve is constructed for different constant current charging times, including 1 min, 2 min, 3 min, 4 min, 5 min, ..., 60 min. If the preset charging rate is 0.1C, the battery is controlled to charge at a 0.1C rate for at least 60 min, and a first reference characteristic curve or a second reference characteristic curve corresponding to this preset charging rate is constructed. If, when the battery is charged at a 1C rate, the second characteristic curve shows an abnormal inflection point when the charging time reaches 35 min, then the target charging time for the 1C rate is determined to be 35 min.

[0075] For example, if the target charging rate is 1.5C, the battery is controlled to charge at a 1.5C rate, and a first characteristic curve or a second characteristic curve is constructed for different constant current charging times, including 1 min, 2 min, 3 min, 4 min, 5 min, ..., 400 min. If the preset charging rate is 0.1C, the battery is controlled to charge at a 0.1C rate for at least 400 min, and a first reference characteristic curve or a second reference characteristic curve corresponding to this preset charging rate is constructed. If, when the battery is charged at a 1.5C rate, the second characteristic curve shows an abnormal inflection point after 150 min of charging, then the target charging time for the 1.5C rate is determined to be 150 min.

[0076] For example, if the target charging rate is 2C, the battery is controlled to charge at a 2C rate, and a first or second characteristic curve is constructed for different constant current charging times, including 1 min, 2 min, 3 min, 4 min, 5 min, ..., 30 min. If the preset charging rate is 0.1C, the battery is controlled to charge at a 0.1C rate for at least 30 min, and a first or second reference characteristic curve corresponding to this preset charging rate is constructed. If, when the battery is charged at a 2C rate, the first characteristic curve shows an abnormal inflection point when the charging time reaches 20 min, then the target charging time for the 2C rate is determined to be 20 min.

[0077] For example, if the target charging rate is 2.5C, the battery is controlled to charge at a 2.5C rate, and a first or second characteristic curve is constructed for different constant current charging times, including 1 min, 2 min, 3 min, 4 min, 5 min, ..., 24 min. If the preset charging rate is 0.1C, the battery is controlled to charge at a 0.1C rate for at least 24 min, and a first or second reference characteristic curve is constructed corresponding to this preset charging rate. If, when the battery is charged at a 2.5C rate, the first characteristic curve shows an abnormal inflection point after 15 min of charging, then the target charging time for the 2.5C rate is determined to be 15 min.

[0078] The target charging time obtained in steps S210 to S220 refers to the target charging time corresponding to a target charging rate. However, there may be multiple target charging rates when controlling the battery charging rate. If it is necessary to determine the target charging time for multiple target charging rates, steps S210 to S220 need to be repeated.

[0079] In an optional embodiment, multiple preset target charging rates and corresponding target charging durations are acquired. Based on each target charging rate and its corresponding target charging duration, target charging data for charging the battery at that rate is determined, enabling the battery to be charged according to this target charging data. This target charging data represents the data that allows the battery to be charged to a preset charging capacity as quickly as possible without lithium plating when charged at the multiple preset target charging rates. When controlling the battery charging using this target charging data, the battery is first controlled to undergo constant current charging. When the real-time voltage of the battery reaches a preset voltage, constant voltage charging is then implemented. The charging process continues until the real-time charging capacity of the battery reaches the preset charging capacity, at which point the charging process ends.

[0080] When controlling the battery to perform constant current charging based on the target charging data, multiple target charging rates are sorted according to the size of each target charging rate. The sorting result includes Z target charging rates arranged from smallest to largest, where the Zth target charging rate is the largest charging rate among multiple target charging rates, and Z is a natural number greater than 1.

[0081] The battery is controlled to perform constant current charging based on the Zth target charging rate and the Zth target charging time corresponding to the Zth target charging rate.

[0082] Decrease Z by 1 and repeat the step of controlling the battery to perform constant current charging with the Zth target charging rate and the Zth target charging time corresponding to the Zth target charging rate until the real-time voltage of the battery reaches the preset voltage.

[0083] For example, if Z equals 4, the Z-th charging rate is 4C, the (Z-1)-th charging rate is 3C, the (Z-2)-th charging rate is 2C, and the (Z-3)-th charging rate is 1.5C, and the preset voltage is 4.5V, then when controlling the battery for constant current charging, a 4C current is first used to control the battery for constant current charging until the battery charging time reaches the target charging time t corresponding to 4C. Z Charging is stopped at this point. Then, the battery is charged at a constant current controlled by 3C until the charging time reaches the target charging time t corresponding to 3C. Z-1 Charging is stopped at this point. Then, a constant current of 2C is used to control the battery's charging until the battery reaches the target charging time t corresponding to 2C. Z-2 Charging is stopped at the designated time. Finally, the battery is charged with a constant current of 1.5C until the real-time voltage of the battery reaches the preset voltage (e.g., 4.5V), at which point the battery is charged with a constant voltage.

[0084] When the battery's real-time voltage reaches 4.5V, constant voltage charging is initiated. Constant voltage charging is stopped when the battery's real-time current reaches 0.02C. Charging continues until the battery's real-time charging capacity reaches the preset charging capacity, at which point charging is terminated.

[0085] In summary, this embodiment provides a method for determining charging time, which includes: obtaining a target charging rate, controlling the battery to perform constant current charging at the target charging rate, and obtaining parameter information during the battery charging process; when lithium plating of the battery is determined based on the parameter information, obtaining the charging time at the time of lithium plating, and using the charging time at the time of lithium plating as the target charging time for the target charging rate.

[0086] That is, before controlling the battery charging rate, the target charging time for a specific target charging rate in the charging data is first determined. The target charging time is determined by controlling the battery to perform constant current charging at the target charging rate and acquiring the parameter information during the charging process. Then, based on this parameter information, it is determined whether lithium plating is imminent during battery charging. If lithium plating is about to occur, the point at which lithium plating is about to occur is determined as the limit time point for controlling battery charging at the target charging rate, and the corresponding charging time is the limit time for controlling battery charging at the target charging rate (target charging time). Thus, before controlling the battery charging rate, the target charging time for each charging rate can be determined according to this method, thereby controlling the battery to prevent lithium plating while achieving rapid charging. Therefore, the charging time determination method provided in this application can solve the problem of how to improve the charging mechanism of lithium-ion batteries, so that when controlling lithium-ion battery charging by charging rate, the charging time at each rate can be effectively controlled to avoid lithium plating while achieving rapid battery charging.

[0087] Please see Figure 6 An embodiment of this application also provides a charging time determination device 10, comprising:

[0088] The acquisition module 11 is used to acquire the target charging rate.

[0089] The control module 12 is used to control the battery to perform constant current charging at the target charging rate.

[0090] The acquisition module 11 is also used to acquire parameter information during the battery charging process.

[0091] The acquisition module 11 is further configured to acquire the charging time of the battery at the lithium plating critical point when the battery is determined to be at the lithium plating critical point based on the parameter information, and use the charging time of the battery at the lithium plating critical point as the target charging time of the target charging rate, wherein the lithium plating critical point represents the state point where the battery is about to plating lithium but has not yet plating lithium.

[0092] The parameter information includes at least one or more of the following sets of information: the first set of information includes the real-time thickness and real-time capacity of the battery; the second set of information includes the real-time voltage and real-time capacity of the battery; the third set of information includes the real-time conductivity of the battery; and the fourth set of information includes the negative electrode surface density of the battery. Specifically, the acquisition module 11 is used to construct a first characteristic curve of the battery based on its real-time thickness and real-time capacity. When an abnormal inflection point appears on the first characteristic curve, it is determined that when the real-time thickness of the battery corresponds to the thickness at the abnormal inflection point, the battery is at the lithium plating critical point; and / or, based on the... A second characteristic curve for the battery is constructed based on its real-time voltage and real-time capacity. When an abnormal inflection point appears on the second characteristic curve, the battery is considered to be at the lithium plating critical point when the real-time voltage is the voltage corresponding to the abnormal inflection point. Alternatively, a third characteristic curve for the battery is constructed based on its real-time conductivity and charging time. When an abnormal inflection point appears on the third characteristic curve, the battery is considered to be at the lithium plating critical point when the real-time conductivity is the conductivity corresponding to the abnormal inflection point. And / or, the battery is considered to be at the lithium plating critical point when the negative electrode surface density is equal to a preset negative electrode surface density.

[0093] The acquisition module 11 is specifically used to acquire a first reference characteristic curve, which is constructed based on the reference real-time thickness and reference real-time capacity of the battery during charging. The reference real-time thickness and reference real-time capacity are acquired when the battery is charged with a preset charging rate and no lithium plating occurs. When the first reference characteristic curve and the first characteristic curve are different, it is determined that the first characteristic curve has an abnormal inflection point, and when it is determined that the real-time thickness of the battery is the thickness corresponding to the abnormal inflection point, the battery is at the lithium plating critical point.

[0094] The acquisition module 11 is specifically used to acquire a second reference characteristic curve, which is constructed based on the reference real-time voltage and reference real-time capacity of the battery during charging. The reference real-time voltage and reference real-time capacity are acquired when the battery is charged at a preset charging rate and no lithium plating has occurred. When the second reference characteristic curve and the second characteristic curve are different, it is determined that the second characteristic curve has an abnormal inflection point, and when it is determined that the real-time voltage of the battery is the voltage corresponding to the abnormal inflection point, the battery is at the lithium plating critical point.

[0095] The acquisition module 11 is also used to acquire multiple preset target charging rates and target charging durations corresponding to each target charging rate; and to determine the target charging data when charging the battery at the target charging rate based on each target charging rate and the target charging duration corresponding to each target charging rate, so as to realize the charging process of the battery based on the target charging data.

[0096] The control module 12 is also used to control the battery to perform constant current charging according to the target charging data; when the real-time voltage of the battery reaches the preset voltage, it controls the battery to perform constant voltage charging until the real-time charging capacity of the battery reaches the preset charging capacity, and then controls the battery to stop charging.

[0097] The control module 12 is specifically used to sort multiple target charging rates according to the size of each target charging rate. The sorting result includes Z target charging rates arranged from smallest to largest, where the Zth target charging rate is the largest charging rate among the multiple target charging rates, and Z is a natural number greater than 1. The battery is controlled to perform constant current charging with the Zth target charging rate and the Zth target charging time corresponding to the Zth target charging rate. Z is decremented by 1, and the step of controlling the battery to perform constant current charging with the Zth target charging rate and the Zth target charging time corresponding to the Zth target charging rate is repeated until the real-time voltage of the battery reaches the preset voltage.

[0098] Please see Figure 7 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, and the processor 21 executes the computer-executable instructions stored in the memory 22 to implement the method for determining charging time as provided in any of the above embodiments.

[0099] 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 method for determining the charging duration as provided in any of the preceding embodiments.

[0100] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the method for determining the charging duration as provided in any of the preceding embodiments.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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.

[0105] 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.

[0106] 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.

[0107] 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.

[0108] 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 method for determining charging time, characterized in that, include: Obtain the target charging rate, control the battery to perform constant current charging at the target charging rate, and obtain parameter information during the battery charging process; When the battery is determined to be at the lithium plating critical point based on the parameter information, the charging time when the battery is at the lithium plating critical point is obtained, and the charging time when the battery is at the lithium plating critical point is taken as the target charging time of the target charging rate. The lithium plating critical point represents the state point where the battery is about to plating lithium but has not yet plating lithium. The parameter information includes multiple sets of information: the first set of information includes the real-time thickness and real-time capacity of the battery; the second set of information includes the real-time voltage and real-time capacity of the battery; the third set of information includes the real-time conductivity of the battery; and the fourth set of information includes the negative electrode surface density of the battery. When the parameter information includes the first set of information, determining that the battery is at the lithium plating critical point based on the parameter information includes: constructing a first characteristic curve of the battery based on the real-time thickness and real-time capacity of the battery, and obtaining a first reference characteristic curve. The first reference characteristic curve is constructed based on the reference real-time thickness and reference real-time capacity of the battery during charging. The reference real-time thickness and reference real-time capacity are obtained when the battery is charged with a preset charging rate and no lithium plating occurs. When the first reference characteristic curve and the first characteristic curve are different, it is determined that the first characteristic curve has an abnormal inflection point, and when the real-time thickness of the battery is the thickness corresponding to the abnormal inflection point, the battery is at the lithium plating critical point.

2. The method according to claim 1, characterized in that, When the parameter information includes the second set of information, determining that the battery is at the lithium plating critical point based on the parameter information includes: constructing a second characteristic curve of the battery based on the real-time voltage and the real-time capacity of the battery; when an abnormal inflection point appears on the second characteristic curve, determining that the battery is at the lithium plating critical point when the real-time voltage of the battery is the voltage corresponding to the abnormal inflection point. When the parameter information includes the third set of information, determining that the battery is at the lithium plating critical point based on the parameter information includes: constructing a third characteristic curve of the battery based on the real-time conductivity of the battery and the charging time of the battery; when the third characteristic curve shows an abnormal inflection point, determining that the real-time conductivity of the battery is the conductivity corresponding to the abnormal inflection point, the battery is at the lithium plating critical point. When the parameter information includes the fourth set of information, determining that the battery is at the lithium plating critical point based on the parameter information includes: determining that the battery is at the lithium plating critical point when the negative electrode surface density of the battery is equal to the preset negative electrode surface density.

3. The method according to claim 2, characterized in that, When the second characteristic curve shows an abnormal inflection point, determining that the real-time voltage of the battery is the voltage corresponding to the abnormal inflection point indicates that the battery is at the lithium plating critical point includes: A second reference characteristic curve is obtained, which is constructed based on the reference real-time voltage and reference real-time capacity when the battery is charging. The reference real-time voltage and reference real-time capacity are obtained when the battery is charged at a preset charging rate and no lithium plating occurs. When the second reference characteristic curve and the second characteristic curve are different, it is determined that the second characteristic curve has an abnormal inflection point, and when it is determined that the real-time voltage of the battery is the voltage corresponding to the abnormal inflection point, the battery is at the lithium plating critical point.

4. The method according to claim 1, characterized in that, The method further includes: Obtain multiple preset target charging rates and the target charging time corresponding to each target charging rate; Based on each target charging rate and the corresponding target charging duration, target charging data for the battery at the specified charging rate is determined, so as to enable the battery to be charged according to the target charging data.

5. The method according to claim 4, characterized in that, The method further includes: The battery is controlled to perform constant current charging based on the target charging data; When the real-time voltage of the battery reaches the preset voltage, the battery is controlled to perform constant voltage charging until the real-time charging capacity of the battery reaches the preset charging capacity, at which point the charging of the battery is stopped.

6. The method according to claim 5, characterized in that, The step of controlling the battery to perform constant current charging based on the target charging data includes: Multiple target charging rates are sorted according to the magnitude of each target charging rate. The sorting result includes Z target charging rates arranged from smallest to largest, where the Zth target charging rate is the largest charging rate among the multiple target charging rates, and Z is a natural number greater than 1. The battery is controlled to perform constant current charging based on the Zth target charging rate and the Zth target charging time corresponding to the Zth target charging rate. Decrease Z by 1, and repeat the step described above, controlling the battery to perform constant current charging with the Zth target charging rate and the Zth target charging time corresponding to the Zth target charging rate, until the real-time voltage of the battery reaches the preset voltage.

7. A device for determining charging time, characterized in that, include: The acquisition module is used to obtain the target charging rate; The control module is used to control the battery to perform constant current charging at the target charging rate; The acquisition module is also used to acquire parameter information during the battery charging process; The acquisition module is further configured to, when it is determined from the parameter information that the battery is at the lithium plating critical point, acquire the charging time when the battery is at the lithium plating critical point, and use the charging time when the battery is at the lithium plating critical point as the target charging time of the target charging rate, wherein the lithium plating critical point represents the state point where the battery is about to plating lithium but has not yet plating lithium. The parameter information includes multiple sets of information: the first set of information includes the real-time thickness and real-time capacity of the battery; the second set of information includes the real-time voltage and real-time capacity of the battery; the third set of information includes the real-time conductivity of the battery; and the fourth set of information includes the negative electrode surface density of the battery. When the parameter information includes the first set of information, and the battery is determined to be at the lithium plating critical point based on the parameter information, the acquisition module is specifically used to: construct a first characteristic curve of the battery based on the real-time thickness and real-time capacity of the battery, and acquire a first reference characteristic curve. The first reference characteristic curve is constructed based on the reference real-time thickness and reference real-time capacity of the battery during charging. The reference real-time thickness and reference real-time capacity are acquired when the battery is charged with a preset charging rate and no lithium plating occurs. When the first reference characteristic curve and the first characteristic curve are different, it is determined that the first characteristic curve has an abnormal inflection point, and when the real-time thickness of the battery is the thickness corresponding to the abnormal inflection point, the battery is at the lithium plating critical point.

8. An electronic device, characterized in that, 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 method for determining the charging time as described in any one of claims 1 to 6.

9. 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 method for determining the charging duration as described in any one of claims 1-6.

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