A battery charging method, device, system, electronic device, and storage medium

Abstract

The application provides a battery charging method, device, system, electronic equipment and storage medium, and relates to the technical field of energy. According to the material characteristics of a battery to be charged, the battery to be charged is divided into multiple charging intervals, and through other battery state information, the requested current value of each setting period of the battery to be charged in the charging process is considered together, so that the battery to be charged is charged at the optimal requested current value within the acceptable charging capacity range during the entire charging process. In this way, the requested current value in the charging process can be adapted to the battery to be charged at this time, the temperature rise of the charging process can be controlled, the charging efficiency can be improved, and the service life of the battery to be charged can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy, in particular to a battery charging method, device, system, electronic equipment and storage medium. BACKGROUND

[0002] With the popularity of electric vehicles, there are more and more problems for electric vehicles. The charging strategy of electric vehicles can affect the charging time, cycle life and operation safety of the battery. Researching and selecting a suitable charging strategy can effectively improve the user experience. Using large rate charging can effectively shorten the charging time, but the continuous high current can cause serious heat generation in the charging process, reduce the energy use efficiency, and exist safety hazards.

[0003] Therefore, the goal of optimizing the charging strategy is to ensure the best balance of charging time, charging capacity and charging process temperature rise, and to achieve the optimal solution of battery life, charging rate, charging energy and charging temperature rise. SUMMARY

[0004] In order to solve the problems in the prior art, the present application provides a battery charging method, system, electronic equipment and storage medium, which realizes charging with the best request current value within the acceptable charging capacity range of the battery to be charged during the entire charging process.

[0005] In a first aspect, the present application provides a battery charging method, which comprises:

[0006] determining the request current value of the current setting period according to the battery state information and the maximum SOC value corresponding to the charging interval in which the current SOC value is located; wherein the battery state information includes at least one of the health state coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value and the current SOC value of the battery to be charged; and the charging interval is determined according to the material characteristics of the battery to be charged;

[0007] controlling the charging unit to charge the battery to be charged within the current setting period according to the determined request current value.

[0008] In the above method, the battery to be charged is divided into multiple charging intervals according to the material characteristics of the battery to be charged, and the request current value of each setting period in the charging process of the battery to be charged is considered together through other battery state information, so that the battery to be charged is charged with the best request current value within the acceptable charging capacity range during the entire charging process. In this way, not only can the request current value in the charging process be adapted to the battery to be charged at this time, but also the temperature rise in the charging process can be controlled, the charging efficiency can be improved, and the service life of the battery to be charged can be improved.

[0009] In a possible implementation, before determining the request current value of the current setting period, the method further includes:

[0010] determining that the current SOC value is less than a first set SOC value;

[0011] The method further includes:

[0012] if the current SOC value is not less than the first set SOC value for the first time, determining a first request current value of the battery to be charged according to battery state information and a maximum SOC value corresponding to a charging interval in which the current SOC value is located;

[0013] charging the battery to be charged according to the first request current value, and continuously reducing the first request current value at a first set current reduction rate until a single highest voltage value of the battery to be charged reaches a set voltage value, then charging the battery to be charged according to a second request current value, and continuously reducing the second request current value at a second set current reduction rate until the second request current value reaches a first set current value, and finally charging the battery to be charged according to a second set current value until the single highest voltage value of the battery to be charged is equal to a cut-off voltage value, and ending the charging process of the battery to be charged; wherein the single highest voltage value is a highest voltage value corresponding to a smallest battery unit included in the battery to be charged.

[0014] In the above method, before charging the battery to be charged, it is determined that the current SOC value is less than the first set SOC value, and when the current SOC value is not less than the first set SOC value, the battery to be charged is charged by means of current reduction charging, and finally the battery to be charged is charged at a constant current value after being reduced to a certain extent, so as to ensure the charging efficiency and safety in the whole charging process.

[0015] In a possible implementation, the battery state information includes a health state coefficient of the battery to be charged, a temperature value corresponding to the current SOC value, an open circuit voltage value corresponding to the current SOC value, and the current SOC value of the battery to be charged.

[0016] The determining of the request current value of the current setting period according to the battery state information and a maximum SOC value corresponding to a charging interval in which the current SOC value is located includes:

[0017] if the current setting period is an initial setting period, determining an initial SOC value of the battery to be charged according to the received voltage signal of the battery to be charged and a power-off duration of the battery to be charged, and taking the initial SOC value as the current SOC value of the battery to be charged;

[0018] The initial terminal voltage value of the received battery to be charged is taken as the open circuit voltage value corresponding to the current SOC value, and the initial temperature of the received battery to be charged is taken as the temperature value corresponding to the current SOC value.

[0019] According to the health state coefficient of the battery to be charged, the initial temperature, the initial SOC value, the initial terminal voltage value, and the maximum SOC value corresponding to the charging interval in which the initial SOC value is located, the request current value of the initial setting period is determined.

[0020] If the current setting period is other than the initial setting period, the current SOC value is determined according to the initial SOC value and the charging current in the current setting period collected by the acquisition unit.

[0021] According to the health state coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, the current SOC value, and the maximum SOC value corresponding to the charging interval in which the current SOC value is located, the request current value of the current setting period is determined.

[0022] In the above method, during the charging of the battery to be charged, various constraint conditions are fully considered, such as the health state coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, and the current SOC value of the battery to be charged. The request current value of the battery to be charged is determined by various constraint conditions, and the request current value of each setting period is the best current value for the battery to be charged, which can effectively control the temperature rise, speed up the charging time, improve the charging efficiency, and ensure the service life of the battery to be charged.

[0023] In a possible implementation, the power-off duration is the length of time from the last time the battery to be charged is disconnected from the power supply to the time when charging starts.

[0024] The initial SOC value of the battery to be charged is determined according to the received voltage signal of the battery to be charged and the power-off duration of the battery to be charged, and includes:

[0025] If the power-off duration is greater than the set duration, the pre-established correspondence between the voltage signal and the SOC value is used to determine the initial SOC value corresponding to the collected voltage signal.

[0026] If the power-off duration is less than or equal to the set duration, the SOC value of the battery to be charged at the last time when the power supply is disconnected is read, and the SOC value at the last time when the power supply is disconnected is taken as the initial SOC value.

[0027] In one possible implementation, determining the requested current value for the initial set period based on the state-of-health coefficient of the battery to be charged, the initial temperature, the initial state of charge (SOC) value, the initial terminal voltage value, and the maximum SOC value corresponding to the charging range in which the initial SOC value is located includes:

[0028] The initial charging rate is determined based on the pre-established SOC value and the correspondence between temperature, SOC value and charging rate.

[0029] The first initial requested current value is determined based on the initial charging rate and the rated capacity of the battery to be charged.

[0030] The second initial requested current value is determined based on the initial open-circuit voltage value and the terminal voltage value corresponding to the maximum stage SOC value in the charging interval where the initial SOC value is located.

[0031] The third initial requested current value is determined based on the initial SOC value and the maximum stage SOC value corresponding to the charging interval in which the initial SOC value is located.

[0032] The initial request current value is determined based on the first initial request current value, the second initial request current value, the third initial request current value, and the health status coefficient.

[0033] In one possible implementation, determining the third initial requested current value based on the initial SOC value and the maximum stage SOC value corresponding to the charging interval in which the initial SOC value is located includes:

[0034] Based on the charging range in which the initial SOC value is located, determine the charging time corresponding to the charging range in which the initial SOC value is located;

[0035] A first intermediate value is determined by the ratio between the product of the coulombic efficiency and the charging time, and the product of a set value and the maximum available rated capacity of the battery to be charged.

[0036] The second intermediate value is determined based on the difference between the initial SOC value and the maximum stage SOC value corresponding to the charging interval in which the initial SOC value is located.

[0037] The third initial requested current value is determined based on the ratio of the second intermediate value to the first intermediate value.

[0038] In one possible implementation, determining the initial requested current value based on the first initial requested current value, the second initial requested current value, the third initial requested current value, and the health status coefficient includes:

[0039] The intermediate request current value is determined based on the first initial request current value, the second initial request current value, the third initial request current value, and the set proportion coefficient;

[0040] The initial request current value is determined based on the product of the intermediate request current value and the health status coefficient.

[0041] In the above method, since the acceptable charging capacity gradually decreases as the degree of degradation of the battery to be charged increases, the above method in this application fully considers the degree of degradation of the battery to be charged as the usage time increases, and requests the current value for the battery to be charged for different usage times based on the current health status coefficient of the battery to be charged, which can effectively improve the charging efficiency of the battery to be charged and extend the service life of the battery to be charged.

[0042] In one possible implementation, determining the current SOC value based on the initial SOC value and the charging current in the current set cycle acquired by the acquisition unit includes:

[0043] A third intermediate value is determined by the ratio between the product of the charging current, the charging time of the battery to be charged, and the coulombic efficiency, and the product of a set value and the maximum usable rated capacity of the battery to be charged.

[0044] The current SOC value is determined based on the difference between the initial SOC value and the third intermediate value.

[0045] Secondly, this application provides a battery charging device, the device comprising:

[0046] A current determination unit is used to determine the requested current value for the current set cycle based on battery status information and the maximum SOC value corresponding to the charging range in which the current SOC value is located; wherein, the battery status information includes at least one of the following: the health status coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, and the current SOC value of the battery to be charged; the charging range is determined based on the material characteristics of the battery to be charged;

[0047] A charging unit is configured to control the charging unit to charge the battery to be charged within the current set period according to the determined requested current value.

[0048] In one possible implementation, the current determination unit is further configured to determine that the current SOC value is less than a first preset SOC value; if the current SOC value is not less than the first preset SOC value for the first time, then the first requested current value of the battery to be charged is determined based on the battery status information and the maximum SOC value corresponding to the charging range in which the current SOC value is located.

[0049] In one possible implementation, the charging unit is further configured to charge the battery to be charged according to the first requested current value, and continuously reduce the first requested current value at a first set current reduction rate until the highest voltage value of a single cell of the battery to be charged reaches a set voltage value. Then, it charges the battery to be charged according to a second requested current value, and continuously reduces the second requested current value at a second set current reduction rate until the second requested current value reaches a first set current value. Finally, it charges the battery to be charged with the second set current value until the highest voltage value of a single cell of the battery to be charged equals the cutoff voltage value, thus ending the charging process of the battery to be charged. The highest voltage value of a single cell is the highest voltage value corresponding to the smallest battery unit included in the battery to be charged.

[0050] Thirdly, this application provides a battery charging system, including: a data acquisition unit, a communication unit, a control unit, and a charging unit;

[0051] The acquisition unit is used to acquire the voltage signal, charging current and temperature value of the battery to be charged, and send the voltage signal, charging current and temperature value of the battery to be charged to the control unit;

[0052] The charging unit is used to send a charging request message to the control unit and receive a charging message sent by the control unit to charge the battery to be charged.

[0053] The control unit is used to receive the voltage signal, charging current and temperature value of the battery to be charged sent by the acquisition unit, and to receive the charging request message sent by the charging unit, and to implement the method described in any one of the first aspects.

[0054] The communication unit is used for communication between the acquisition unit and the control unit, and for communication between the charging unit and the control unit.

[0055] Fourthly, embodiments of this application provide an electronic device, including a memory and a processor, wherein a computer program is executable on the processor and, when executed by the processor, implements the method described in any one of the first aspects.

[0056] Fifthly, embodiments of this application provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the method described in any one of the first aspects.

[0057] The technical effects of any of the implementation methods in aspects two through five can be found in the technical effects of the corresponding implementation methods in aspect one, and will not be repeated here. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 This is a schematic diagram of the structure of a battery charging system provided in an embodiment of this application;

[0060] Figure 2 This is a schematic diagram of the structure of a data acquisition unit provided in an embodiment of this application;

[0061] Figure 3 A schematic flowchart illustrating a battery charging method provided in an embodiment of this application;

[0062] Figure 4 This is a schematic diagram illustrating the mapping relationship between the SOC value and open-circuit voltage of a lithium-ion battery provided in an embodiment of this application.

[0063] Figure 5 A schematic flowchart illustrating another battery charging method provided in an embodiment of this application;

[0064] Figure 6 A charging rate table for a lithium-ion battery cell based on temperature characteristics is provided for embodiments of this application;

[0065] Figure 7 A schematic diagram of an equivalent circuit model provided in an embodiment of this application;

[0066] Figure 8 A schematic diagram of the acceptable current curve of a battery to be recharged, provided for an embodiment of this application;

[0067] Figure 9 A schematic flowchart illustrating another battery charging method provided in an embodiment of this application;

[0068] Figure 10 This is a schematic diagram of the structure of a battery charging device provided in an embodiment of this application;

[0069] Figure 11 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0071] It should be noted that the terms "comprising" and "having" and their variations used in this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0072] Existing technologies for battery charging include the following methods: the traditional constant current and constant voltage charging strategy, which first charges with a constant current, and then switches to constant voltage charging when the voltage reaches a threshold. This method is simple and easy to implement, but the constant voltage stage has a long charging time, and the polarization effect generated during the process reduces the battery's charging efficiency. Furthermore, it cannot guarantee that the constant current is always the optimal charging current for the battery.

[0073] The multi-stage constant current charging strategy divides the charging process into several constant current segments. Optimizing the charging sequence can effectively shorten the charging time, but it does not take into account the aging of the battery during the charging process, nor can it guarantee that the constant current in each stage is the optimal charging current for the battery.

[0074] To address the aforementioned issues, the inventors have fully considered various factors that may affect the battery to be recharged and have provided the following method: Based on the battery state information and the maximum SOC value corresponding to the charging range where the current State of Charge (SOC) value is located, the requested current value for the current set period is determined. The battery state information includes at least one of the following: the battery's health status coefficient, the temperature value corresponding to the current SOC value, the open-circuit voltage value corresponding to the current SOC value, and the current SOC value of the battery to be recharged. The charging range is determined based on the material characteristics of the battery to be recharged. Based on the determined requested current value, the charging unit is controlled to charge the battery to be recharged within the current set period.

[0075] The above-mentioned battery charging method dynamically updates the requested current value throughout the entire charging process, ensuring that the charging range is within the acceptable charging capacity of the battery to be charged. It charges with the optimal requested current value, thereby controlling the temperature rise during the charging process, ensuring the best charging capacity level, improving charging efficiency, minimizing battery damage, and extending the service life of the battery to be charged.

[0076] The battery charging provided in this application embodiment can be applied to electronic devices, which can be servers, charging piles, or control units in a battery charging system. Taking an electronic device as a control unit in a battery charging system as an example... Figure 1 The control unit 12 in the battery charging system shown.

[0077] Figure 1 A schematic diagram of a battery charging system according to an embodiment of this application is shown. See also Figure 1 As shown, the battery charging system 10 includes a data acquisition unit 11, a control unit 12, a charging unit 13, and a communication unit 14.

[0078] The acquisition unit 11 is used to acquire the voltage signal, charging current and temperature value of the battery to be charged, and send the voltage signal, charging current and temperature value of the battery to be charged to the control unit 12.

[0079] For example, such as Figure 2 As shown, the acquisition unit 11 may include a voltage sensor 111, a temperature sensor 112, and a digital Hall sensor 113. The voltage sensor acquires the voltage value of each individual battery cell to be recharged, and obtains the voltage signal of the battery based on the voltage value of each individual cell. The temperature sensor acquires the surface temperature of each individual battery cell, and obtains the temperature value of the battery based on the surface temperature of each individual cell. The digital Hall sensor acquires the charging current. The charging current acquisition can also be replaced by a shunt and a Hall sensor. Each battery cell is the smallest unit of the battery to be recharged.

[0080] The charging unit 13 is used to send a charging request message to the control unit 12 and receive a charging message sent by the control unit 12 to charge the battery to be charged.

[0081] The control unit 12 is used to receive the voltage signal, charging current, and temperature value of the battery to be charged sent by the acquisition unit 11, and to receive the charging request message sent by the charging unit 13, and to perform the following steps:

[0082] Based on the battery status information and the maximum SOC value corresponding to the current SOC value within the charging range, the requested current value for the current set cycle is determined. Based on the determined requested current value, the charging unit is controlled to charge the battery to be charged within the current set cycle. The battery status information includes at least one of the following: the battery's health status coefficient, the temperature value corresponding to the current SOC value, the open-circuit voltage value corresponding to the current SOC value, and the current SOC value of the battery to be charged. The charging range is determined based on the material characteristics of the battery to be charged.

[0083] The communication unit 14 is used for communication between the acquisition unit 11 and the control unit 12, and for communication between the charging unit 13 and the control unit 12.

[0084] To further illustrate the technical solutions provided in the embodiments of this application, a detailed description is provided below in conjunction with the accompanying drawings and specific implementation methods. Although the embodiments of this application provide method operation steps as shown in the following embodiments or drawings, the method may include more or fewer operation steps based on conventional or non-inventive methods. In steps where there is no logically necessary causal relationship, the execution order of these steps is not limited to the execution order provided in the embodiments of this application.

[0085] See Figure 3 This is a schematic flowchart illustrating a battery charging method provided in an embodiment of this application. The charging process of the battery to be charged will be described in detail below, such as... Figure 3 As shown, the method includes the following steps:

[0086] Step S301: Determine the requested current value for the current set cycle based on the battery status information and the maximum SOC value corresponding to the charging range in which the current SOC value is located.

[0087] The battery status information includes at least one of the following: the health status coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, and the current SOC value of the battery to be charged.

[0088] Specifically, the charging range is determined based on the material characteristics of the battery to be charged. Due to its advantages such as low self-discharge, no memory effect, and the ability to be repeatedly charged and discharged, lithium-ion batteries have become the primary choice for electric vehicle power sources. Therefore, the battery charging method provided in this application uses a lithium-ion battery as an example. Lithium-ion batteries can be divided into many types, and the charging methods differ depending on the material properties used. This application will use a lithium-ion battery made of lithium iron phosphate material, which has a relatively complex charging process and a more pronounced charging curve, as an example. Figure 4 As shown.

[0089] Figure 4 A schematic diagram showing the mapping relationship between the SOC value and open circuit voltage (OCV) of a lithium-ion battery is presented, as shown below. Figure 4As shown in the diagram, lithium-ion batteries can be divided into five ranges. The ranges are divided by the SOC value, expressed as a percentage (%). The SOC value of the low-end charging range is [0, 20], the SOC value of the first intermediate charging range is (20, 50], the SOC value of the second intermediate charging range is (50, 75], the SOC value of the third intermediate charging range is (75, 90], and the SOC value of the high-end charging range is (90, 100).

[0090] In the low-end charging range, the usable capacity of the battery is relatively low, and the ohmic resistance and polarization resistance are relatively high, posing a risk of over-discharge. This range is also considered a safe charging range. In the middle charging range, the battery's chemical characteristics are relatively stable with minimal variation. As the charging capacity increases, the acceptable charging capacity gradually decreases, thus requiring current-reducing charging within the battery's acceptable charging capacity. In the high-end charging range of SOC, the polarization level gradually increases, and the temperature difference between the battery and the environment also gradually increases. Maintaining a constant current will cause lithium crystallization at the negative electrode, leading to greater irreversible capacity loss. Therefore, linear-phase current-reducing charging is recommended in this range to ensure optimal charging capacity while gradually reducing battery polarization.

[0091] Batteries with different material properties generally have a high-end charging range. Therefore, for all types of batteries, when the SOC value is in the high-end charging range, a linear phased current reduction charging method can be used. It should be noted that the specific SOC value boundary of the high-end charging range is determined according to the material properties of the battery. Therefore, the SOC value boundary of the high-end charging range does not necessarily have to be 90% SOC. Depending on the material properties of other batteries, the boundary of the high-end charging range can also be 80%, 85%, etc.

[0092] The lower boundary of the high-end charging range is taken as the first set SOC value. When it is determined that the current SOC of the battery to be charged is less than the first set SOC value, the requested current value is determined in step S301. When it is determined that the current SOC value is not less than the first set SOC value for the first time, charging is performed in the following manner: Specifically, it can be divided into two methods:

[0093] The first method: such as Figure 5 As shown, Figure 5 A flowchart illustrating another battery charging method is shown, including the following steps:

[0094] Step S501: Determine the first requested current value of the battery to be charged based on the battery status information and the maximum SOC value corresponding to the charging range in which the current SOC value is located.

[0095] Step S502: Charge the battery to be charged according to the first requested current value, and continuously reduce the first requested current value at a first set current reduction rate until the highest voltage value of a single cell of the battery to be charged reaches the set voltage value, and determine the second requested current value.

[0096] The second requested current value is the requested current value of the battery to be charged when the battery is charged according to the first requested current value, and the first requested current value is continuously reduced at a first set current reduction rate until the highest voltage value of a single cell of the battery to be charged reaches the set voltage value.

[0097] Step S503: Charge the battery to be charged according to the second requested current value, and continuously reduce the second requested current value at a second set current reduction rate until the second requested current value reaches the first set current value.

[0098] Step S504: Charge the battery to be charged using the second set current value until the highest voltage value of a single cell of the battery to be charged is equal to the cutoff voltage value, and end the charging process of the battery to be charged.

[0099] Among them, the highest voltage value of a single cell is the highest voltage value corresponding to the smallest battery unit included in the battery to be charged.

[0100] For example, taking a first set SOC value of 90% as an example, when the battery to be charged is charged, if the current SOC value of the battery to be charged is not less than 90% for the first time, then the first requested current value is determined based on the battery status information and the maximum SOC value corresponding to the charging range in which the current SOC value is located, i.e., the maximum SOC value of the high-end charging range of 100%. The first requested current value is 5.5A as an example.

[0101] It should be noted that due to the characteristics of some batteries, they may be limited from being charged to 100% SOC during the charging process. This explanation only uses 100% as an example. The maximum SOC value in the specific high-end charging range depends on the situation.

[0102] After the first requested current value is determined, the battery to be charged is charged using the first requested current value, and the charging is carried out in a linear current reduction manner. The first requested current value is reduced while the battery to be charged is charged. Here, the first requested current value can be reduced at 5A / min. When the highest voltage value of a single cell of the battery to be charged reaches the set voltage value, the first current reduction period is determined based on the start time when the first requested current value is reduced and the end time when the highest voltage value of a single cell of the battery to be charged reaches the set voltage value. Taking 20s as an example, the second requested current value can be determined as 23 / 6A.

[0103] It should be noted that the set voltage value here can be determined by taking the cutoff voltage value during the charging process as an example, for example, 0.2V lower than the cutoff voltage value.

[0104] After determining the second requested current value, the battery is charged according to this value, and the second requested current value is continuously reduced at a second set current reduction rate of 10A / min until it reaches the first set current value. Taking the second current reduction period as 20s, the first set current value can be determined as 0.1C = 0.5A based on 23 / 6 - 10*1 / 3 = 0.5A. Here, 1C represents the battery's rated capacity, which can be taken as an example of a 5Ah battery.

[0105] The battery to be charged can be charged according to the second set current value. The first and second set current values ​​can be the same, i.e., 0.5A. Alternatively, the first and second set current values ​​can be different, in which case the second set current value is 0.05C = 0.25A.

[0106] By charging the battery to be charged with a second set current value, the highest voltage value of each individual cell of the battery to be charged can be equal to the cutoff voltage value, thus completing the charging process of the battery to be charged.

[0107] The second method: When the current SOC value of the battery to be charged is determined to be no less than 90% for the first time, the battery can be directly charged with a current of 0.1C = 0.5A. The charging process continues until the highest voltage value of each individual cell of the battery equals the cutoff voltage value.

[0108] The above process is a charging method based on the high-end charging range that exists in different material properties of the battery to be charged. If the current SOC value of the battery to be charged is less than the first set value, the specific charging method is to determine the requested current value in the current set cycle and charge the battery to be charged. The specific method is as follows:

[0109] In one possible embodiment, if the battery status information includes the current SOC value of the battery to be charged and the maximum SOC value corresponding to the charging interval in which the current SOC value is located, the SOC difference between the current SOC value and the maximum SOC value corresponding to the charging interval in which the current SOC value is located can be determined. Based on the SOC difference, the requested current value for the current set period can be determined in real time.

[0110] In another possible embodiment, if the battery status information includes the current SOC value of the battery to be charged, the temperature value corresponding to the current SOC value, and the maximum SOC value corresponding to the charging interval in which the current SOC value is located, then a portion of the requested current value for the current set period can be determined by looking up a table based on the current SOC value and the temperature value corresponding to the current SOC value. Then, another portion of the requested current value for the current set period can be determined based on the SOC difference between the current SOC value and the maximum SOC value corresponding to the charging interval in which the current SOC value is located.

[0111] In another possible embodiment, if the battery status information includes the health status coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, and the current SOC value of the battery to be charged, the requested current value for the current set cycle can be determined more accurately.

[0112] Step S302: Based on the determined requested current value, control the charging unit to charge the battery to be charged within the current set cycle.

[0113] The charging process for the battery described above is illustrated using battery status information, including the battery's state of health coefficient, the temperature corresponding to the current SOC value, the open-circuit voltage corresponding to the current SOC value, and the current SOC value of the battery. The maximum SOC value corresponding to each charging interval is as described above. Figure 4 Take the intervals divided by the curve graph as an example.

[0114] The requested current value is determined based on the state of health coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, the current SOC value of the battery to be charged, and the maximum SOC value corresponding to the charging range in which the current SOC value is located.

[0115] The way to determine the current SOC value differs depending on whether the current setting period is the initial setting period or a setting period other than the initial setting period, and consequently, the way to determine the requested current value also differs.

[0116] When the current set period is the initial set period, the requested current value is determined as follows:

[0117] First, the initial SOC value of the battery to be charged needs to be determined, and this initial SOC value will be used as the current SOC value of the battery. Taking an initial SOC value of 30% as an example, it can be determined that the initial SOC value is located within the first intermediate charging range (20, 50).

[0118] For example, if the power-off duration is longer than the set duration, the correspondence between the pre-established voltage signal and the SOC value is used to determine the initial SOC value corresponding to the collected voltage signal. If the power-off duration is less than or equal to the set duration, the SOC value of the battery to be charged at the last time it was disconnected from the power source is read, and the SOC value at the last time it was disconnected from the power source is used as the initial SOC value.

[0119] The power-off duration is the length of time from the last time the battery was disconnected from the power source until the start of charging.

[0120] The initial temperature value of the battery to be charged is acquired by the acquisition unit at the start of charging, and the initial temperature value is used as the temperature value of the initial set cycle.

[0121] During the initial setting period, the initial terminal voltage value can be used as the open-circuit voltage value corresponding to the current SOC value. The initial terminal voltage value can be acquired by the acquisition unit.

[0122] Finally, based on the battery's state of health coefficient, initial temperature, initial SOC value, initial terminal voltage value, and the maximum SOC value corresponding to the charging range in which the initial SOC value lies, the requested current value for the initial set cycle is determined. The specific method is as follows:

[0123] The requested current value can be divided into three parts: a first initial requested current value, a second initial requested current value, and a third initial requested current value. The initial requested current value is determined based on the first initial requested current value, the second initial requested current value, the third initial requested current value, and the health status coefficient.

[0124] The method for determining the first initial requested current value is as follows: based on the pre-established SOC value and the correspondence between temperature, SOC value and charging rate, the initial charging rate is determined, and based on the initial charging rate and the rated capacity of the battery to be charged, the first initial requested current value is determined.

[0125] The relationship between temperature, SOC value, and charging rate is as follows: Figure 6 As shown, Figure 6 A charging rate table for a lithium-ion battery cell based on temperature characteristics is shown.

[0126] For example, if the initial SOC value is 30% and the temperature value is 15 degrees Celsius (°C), the charging rate can be determined to be 0.9C, where C represents the rated capacity of the battery. If the rated capacity of the battery is 10Ah, the first initial requested current value can be 9A; if the rated capacity of the battery is 5Ah, the first initial requested current value can be 4.5A. The first initial requested current value can be expressed as I. req1 .

[0127] The second initial requested current value is determined by: determining the second initial requested current value based on the initial open-circuit voltage value and the terminal voltage value corresponding to the maximum stage SOC value in the charging interval where the initial SOC value is located.

[0128] Specifically, when calculating the second initial requested current value based on voltage characteristics, a Rint equivalent circuit model can be established for the lithium-ion battery, such as... Figure 7 As shown. The terminal voltage of each cell in the battery to be recharged can then be expressed as:

[0129] U = U oc (SOC)-R0*I

[0130] Among them, U oc U is the open-circuit voltage, R0 is the terminal voltage, I is the ohmic impedance, and I represents the current flowing through the battery to be charged. oc (SOC) represents the open-circuit voltage value corresponding to the SOC value of the battery to be charged.

[0131] The terminal voltage corresponding to the maximum SOC value in each charging interval is used as a constraint. The terminal voltage corresponding to the maximum SOC value in each charging interval can be obtained through capacity calibration tests of the battery to be charged, which will not be elaborated here.

[0132] The second initial requested current value can be expressed as:

[0133]

[0134] Among them, U SOC,max This represents the terminal voltage value corresponding to the maximum SOC value for each charging interval.

[0135] Among them, U oc This represents the open-circuit voltage of the battery to be charged. The initial open-circuit voltage at the start of charging can be approximated by the battery's terminal voltage. Initial U SOC,max This is the terminal voltage value corresponding to a SOC value of 50%.

[0136] R0 is the ohmic impedance, which can be set with reference to the cell specification sheet. This value will gradually increase as the battery ages. For cells with a certain level of aging, the influence of the aging factor of the battery to be charged on the ohmic impedance can be considered to determine a new ohmic impedance value, for example: aging factor * R0.

[0137] The method for determining the third initial requested current value is as follows: Based on the charging range in which the initial SOC value is located, determine the charging time corresponding to the charging range in which the initial SOC value is located; determine the first intermediate value based on the ratio between the product of the coulombic efficiency and the charging time and the product of the set value and the maximum available rated capacity of the battery to be charged; determine the second intermediate value based on the difference between the initial SOC value and the maximum stage SOC value corresponding to the charging range in which the initial SOC value is located; and determine the third initial requested current value based on the ratio of the second intermediate value to the first intermediate value.

[0138] For example, based on the initial SOC value and the charging range in which the initial SOC value is located, the third initial requested current value can be expressed as:

[0139]

[0140] Where SOC represents the current SOC value, which is the initial SOC value; SOC max This represents the maximum SOC value for each charging interval, which is 50%; C max This represents the maximum usable rated capacity of the battery to be charged. Δt′ represents the continuous charging time.

[0141] Here, Δt′ is related to the preset charging time T, but is not less than the charging time when fast charging at the maximum rate allowed in the specifications. At the start of charging, Δt′ is calculated using the following formula, and during the charging process, it remains the set value.

[0142] At the start of charging, i.e., at the initial set period, Δt′ can be expressed as:

[0143]

[0144] Among them, SOC min This represents the minimum SOC value for each charging interval. SOC represents the initial SOC value. T is the pre-set charging time for each charging interval.

[0145] Based on the above formula, the third initial requested current value can be determined.

[0146] After determining the first, second, and third initial requested current values, the initial requested current value I can be determined. req .

[0147] I req =β*[I req1 *α+I req2 *(1-α) 2 +I req3 *(1-α) 2 ]

[0148] Where β represents the health status coefficient; β∈(0,1], when β=1 it means the battery to be charged is in brand new condition; α is the proportion coefficient of the given current constraint, α∈(0.6,1], the proportion coefficient is the safe use limit, and the proportion should not be less than 0.6.

[0149] It should be noted that all current values ​​here are positive.

[0150] When charging at the same temperature and state of charge (SOC), the acceptable charging capacity gradually decreases as the battery deteriorates. Therefore, under constant temperature and SOC conditions, the lookup charging current obtained based on temperature and SOC needs to be multiplied by the battery's current aging factor. Otherwise, overcharging can easily occur, leading to lithium crystallization at the negative electrode or shedding of active material from the plates, causing irreversible damage to the battery. Therefore, under constant temperature and SOC conditions, the requested current value needs to be determined based on the state of health factor.

[0151] The above process assumes the current set period is the initial set period. If the current set period is a different set period than the initial set period, the method for determining the requested current value is as follows:

[0152] Based on the initial SOC value and the charging current collected by the acquisition unit in the current set cycle, the current SOC value is determined. Based on the health state coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, the current SOC value, and the maximum SOC value corresponding to the charging range in which the current SOC value is located, the requested current value for the current set cycle is determined.

[0153] For example, if the current setting period is the next setting period after the initial setting period, that is, the current setting period is the second setting period.

[0154] The current SOC value is determined by ampere-hour integration, as shown in the following formula:

[0155]

[0156] Among them, SOC t0 The initial SOC value is represented by Δt, which represents the charging time and can also be understood as the sampling frequency. t Represented as the previous SOC value; I t This indicates the charging current.

[0157] It should be noted that the requested current value is the current value requested by the control unit. It primarily represents the current value desired to charge the battery. However, during the charging process, there are losses, and the requested current value is not necessarily the actual charging current value of the battery. Therefore, the control unit determines the requested current value and sends a charging message to the charging unit. During charging, the acquisition unit collects the corresponding charging current value for each set cycle based on the different requested current values. The charging current value here is based on the actual data collected by the acquisition unit; the charging current value calculated based on the loss rate is inaccurate. Therefore, the requested current value for each set cycle can be used to characterize the start and end of each set cycle and can be used to trigger the acquisition unit to collect the charging current for that set cycle.

[0158] Specifically, at the beginning of each set cycle, when the control unit determines the requested current value and begins charging the battery to be charged, the acquisition unit collects the charging current at that moment as I. t Alternatively, at the start of each set cycle, when the control unit determines the requested current value, the acquisition unit begins acquiring the charging current and continues acquiring it until the end of the set cycle. The average value of the charging current acquired within that set cycle is then used as I. t .

[0159] Using the formula above, the real-time SOC value of the battery to be charged can be determined at the end of each set cycle. By continuously determining the current SOC value for the current set cycle in this way, the requested current value corresponding to the current SOC value can be determined.

[0160] Specifically, the requested current value for the second set cycle is also divided into three parts: requested current value 1, requested current value 2, and requested current value 3. Taking a sampling time of 1 second as an example, after a charging time of 1 second, the second set cycle is reached. If the current SOC value of the second set cycle is 31%, it is also located in the first intermediate charging interval (20, 50).

[0161] The method for determining the requested current value 1 is as follows:

[0162] For example, the acquisition unit acquires the temperature value of the battery to be charged when it is at the current SOC value, and uses this as the current temperature value, with a temperature value of 15 degrees Celsius. Based on the current temperature value and the current SOC value, through... Figure 6 Determine the charging rate and the requested current value 1. The requested current value 1 can be determined through I. req1 'express.

[0163] Based on the charging rate and rated capacity corresponding to a SOC value of 31%, the requested current value is determined as 1.

[0164] The method for determining the requested current value 2 is as follows:

[0165]

[0166] Among them, U oc This represents the open-circuit voltage value corresponding to the current SOC value. Here, U... oc The SOC value can be obtained by looking up the OCV-SOC table.

[0167] U SOC,max This indicates the terminal voltage value corresponding to the maximum SOC value within the charging range where the current SOC value is located.

[0168] It should be noted that this example uses the current SOC value corresponding to the second set cycle, then U SOC,max This refers to the terminal voltage value corresponding to a SOC value of 50%. Taking the 100th setting cycle as an example, the current SOC value corresponding to the 100th setting cycle might be 60%, which is already in the second intermediate charging range. At this time, U... SOC,max This is the terminal voltage value corresponding to a SOC value of 75%.

[0169] When the current SOC value is different, U SOC,max The values ​​are also different.

[0170] The method for determining the requested current value 3 is as follows:

[0171] During the charging process, the current SOC value is determined in real time using the ampere-hour integration method, such as... Figure 8 As shown in the diagram, the acceptable current value of the battery to be recharged decreases as the SOC value of the battery increases. The formula for determining the requested current value 3 is as follows:

[0172]

[0173] Among them, I req3 ′ indicates the requested current value is 3; SOC indicates the current SOC value, which is the current SOC value corresponding to the second set cycle; SOC max It is 50%; Δt′ represents the continuous charging time.

[0174] Here, Δt′ is related to the preset charging time T, but is not less than the charging time when fast charging at the maximum rate allowed in the specifications. At the start of charging, Δt′ is calculated using the following formula, and during the charging process, it remains the set value.

[0175] During the charging process, Δt′ can be expressed as:

[0176] Δt′=0.2T

[0177] Where T is the pre-set charging time for each charging interval.

[0178] Based on the above formula, the requested current value of 3 can be determined.

[0179] After determining the requested current value 1, requested current value 2, and requested current value 3, the initial requested current value I can be determined. req .

[0180] I req =β*[I req1 *α+I req2 *(1-α) 2 +I req3 *(1-α) 2 ]

[0181] Where β represents the health status coefficient; β∈(0,1], when β=1 it means the battery to be charged is in brand new condition; α is the proportion coefficient of the given current constraint, α∈(0.6,1], the proportion coefficient is the safe use limit, and the proportion should not be less than 0.6.

[0182] In the above method, the battery to be charged is divided into multiple charging zones based on its material characteristics. By combining this with other battery state information, the requested current value for each set cycle during charging is considered. This ensures that the battery is charged at the optimal requested current value within its acceptable charging capacity throughout the entire charging process. This approach not only guarantees that the requested current value is consistently appropriate for the battery during charging but also controls the overall temperature rise during charging, improving charging efficiency and extending the battery's lifespan.

[0183] Figure 9 This application illustrates a detailed battery charging method provided by an embodiment of the present application, using an initial SOC value of 60% as an example. Figure 9 As shown, the battery charging method provided in this application includes the following steps:

[0184] Step S901: Determine the requested current value for the current set cycle based on the initial SOC value, initial temperature value, initial open circuit voltage value, and the maximum SOC value of 75% in the second intermediate charging range where the initial SOC value is located.

[0185] Step S902: Determine the current SOC value of the battery to be charged by ampere-hour integration based on the initial SOC value.

[0186] Step S903: The SOC value of the battery to be charged is less than 90%, and it is determined whether the current SOC value of the battery to be charged is in the second intermediate charging range; if yes, proceed to step S904; if no, proceed to step S905.

[0187] Step S904: Based on the current SOC value of the battery to be charged, the temperature value corresponding to the current SOC value, the open-circuit voltage value corresponding to the current SOC value, and the maximum SOC value of the second intermediate charging range in which the current SOC value is located, determine the requested current value for the current set cycle. Then return to execute step S902.

[0188] Step S905: Based on the current SOC value of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, and the maximum SOC value of 90% in the third intermediate charging interval where the current SOC value is located, determine the requested current value for the current set cycle.

[0189] Step S906: Determine the current SOC value of the battery to be charged by ampere-hour integration based on the initial SOC value.

[0190] Step S907: Determine that the SOC value of the battery to be charged is less than 90%, and determine whether the SOC value of the battery to be charged is within the third intermediate charging range; if yes, proceed to step S908; if no, proceed to step S909.

[0191] Step S908: Based on the current SOC value of the battery to be charged, the temperature value corresponding to the current SOC value, the open-circuit voltage value corresponding to the current SOC value, and the maximum SOC value of the second intermediate charging range in which the current SOC value is located, determine the requested current value for the current set cycle. Then return to execute step S906.

[0192] Step S909: Determine the requested current value for the current set cycle based on the current SOC value of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, and the maximum SOC value of the third intermediate charging interval in which the current SOC value is located.

[0193] Step S910: Determine the current SOC value of the battery to be charged by ampere-hour integration based on the initial SOC value.

[0194] Step S911: Determine whether the current SOC value of the battery to be charged is not less than 90%, and charge the battery to be charged with a trickle current of 0.1C until the highest voltage of a single cell of the battery to be charged is equal to the cutoff voltage value, and the charging is completed.

[0195] The battery charging method provided in this application can determine the initial SOC value, initial temperature value, initial open-circuit voltage value, and the maximum SOC value within the charging range where the initial SOC value is located at the start of charging. The requested current value for the initial set period can be determined using these variables. After determining the requested current value for the initial set period, the SOC value of the battery to be charged will inevitably increase. Therefore, the requested current value for the battery to be charged is re-determined based on the increased SOC value. The specific solution method has been described in detail above and will not be repeated here.

[0196] After determining the SOC value of the battery to be charged in real time, since the maximum SOC value of the charging range in which the current SOC value is located is used in the process of determining the requested current value, it is necessary to judge the current SOC value. If the current SOC value is not greater than the maximum SOC value of the charging range in which the initial SOC value is located, it means that the maximum SOC value of the charging range in which the current SOC value is located has not changed, and the charging range has not changed. Therefore, to determine the requested current value corresponding to the current SOC value, there are three variables, as follows:

[0197] The temperature value of the battery to be charged, the current SOC value, and the open circuit voltage value corresponding to the current SOC value.

[0198] However, if the current SOC value is greater than the maximum SOC value of the charging range in which the initial SOC value is located, it means that the charging range has changed. The maximum SOC value of the charging range in which the current SOC value is located is no longer the maximum SOC value of the charging range in which the initial SOC value is located. Therefore, to determine the requested current value corresponding to the current SOC value, there are four variables, as follows:

[0199] The temperature of the battery to be charged, the current SOC value, the open circuit voltage corresponding to the current SOC value, and the maximum SOC value corresponding to the charging range in which the current SOC value is located.

[0200] Once the SOC value of the battery to be charged is not less than 90%, it can be charged with a trickle current of 0.1C until the highest voltage of a single cell of the battery to be charged is equal to the cutoff voltage value, and the charging is complete.

[0201] Based on the same inventive concept, this application also provides a battery charging device. Figure 10 This is a schematic diagram of the structure of a battery charging device provided in an embodiment of this application; as shown. Figure 10 As shown, the device includes:

[0202] The current determination unit 1001 is used to determine the requested current value for the current set cycle based on the battery status information and the maximum SOC value corresponding to the charging range in which the current SOC value is located; wherein, the battery status information includes at least one of the following: the health status coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, and the current SOC value of the battery to be charged; the charging range is determined based on the material characteristics of the battery to be charged.

[0203] The charging unit 1002 is used to control the charging unit to charge the battery to be charged within the current set period according to the determined requested current value.

[0204] This application also provides an electronic device that can be used to execute a battery charging method. This electronic device can be a control unit in a battery charging system. The electronic device includes at least a memory for storing data and a processor. The processor for data processing can be implemented using a microprocessor, CPU, GPU (Graphics Processing Unit), DSP, or FPGA. The memory stores operation instructions, which can be computer-executable code, to implement the various steps in the battery charging method described in this application.

[0205] Figure 11 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 11 As shown, the electronic device 1100 includes a memory 1101, a processor 1102, a data acquisition module 1103, and a bus 1104. The memory 1101, the processor 1102, and the data acquisition module 1103 are all connected via the bus 1104, which is used for data transmission between the memory 1101, the processor 1102, and the data acquisition module 1103.

[0206] The memory 1101 can be used to store software programs and modules. The processor 1102 executes various functional applications and data processing of the electronic device 1100 by running the software programs and modules stored in the memory 1101, such as the battery charging method provided in this application embodiment. The memory 1101 may mainly include a program storage area and a data storage area. The program storage area may store the operating system, application programs of at least one application, etc.; the data storage area may store data created according to the use of the electronic device 1100, etc. In addition, the memory 1101 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0207] The processor 1102 is the control center of the electronic device 1100. It connects to various parts of the electronic device 1100 via the bus 1104 and various interfaces and lines. It executes various functions and processes data of the electronic device 1100 by running or executing software programs and / or modules stored in the memory 1101, and by calling data stored in the memory 1101. Optionally, the processor 1102 may include one or more processing units, such as a CPU, GPU (Graphics Processing Unit), or digital processing unit.

[0208] The data acquisition module 1103 is used to acquire data, such as temperature values ​​and voltage signals from the acquisition unit.

[0209] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, can be used to implement the battery charging method described in any embodiment of this application.

[0210] In some possible implementations, various aspects of the battery charging method provided in this application can also be implemented as a program product comprising program code that, when run on a computer device, causes the computer device to perform the steps of the battery charging method according to the various exemplary embodiments of this application described above. For example, the computer device may perform actions such as... Figure 3 The flowchart of the battery charging method shown in steps S301 to S302 is as follows.

[0211] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0212] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should 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 illustrations. Figure 1One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0213] 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.

[0214] 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.

[0215] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A battery charging method, characterized in that, The method includes: If the current set period is the initial set period, the initial SOC value of the battery to be charged is determined based on the received voltage signal of the battery to be charged and the power-off time of the battery to be charged, and the initial SOC value is used as the current SOC value of the battery to be charged. The initial terminal voltage value of the battery to be charged received is used as the open circuit voltage value corresponding to the current SOC value, and the initial temperature of the battery to be charged received is used as the temperature value corresponding to the current SOC value. The requested current value for the initial set cycle is determined based on the state of health coefficient of the battery to be charged, the initial temperature, the initial state of charge (SOC) value, the initial terminal voltage value, and the maximum SOC value corresponding to the charging range in which the initial SOC value is located; the charging range is determined based on the material properties of the battery to be charged. If the current set period is a set period other than the initial set period, then the current SOC value is determined based on the initial SOC value and the charging current in the current set period collected by the acquisition unit. Based on the state of health coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open-circuit voltage value corresponding to the current SOC value, the current SOC value, and the maximum SOC value corresponding to the charging range in which the current SOC value is located, the requested current value for the current set period is determined; Based on the determined requested current value, the charging unit is controlled to charge the battery to be charged within the currently set cycle.

2. The method according to claim 1, characterized in that, Before determining the requested current value for the current set period, the method further includes: It is determined that the current SOC value is less than the first set SOC value; The method further includes: If the current SOC value is not less than the first set SOC value for the first time, then the first requested current value of the battery to be charged is determined according to the battery status information and the maximum SOC value corresponding to the charging range in which the current SOC value is located. The battery to be charged is charged according to the first requested current value, and the first requested current value is continuously reduced at a first set current reduction rate until the highest voltage value of a single cell of the battery to be charged reaches a set voltage value. Then, the battery to be charged is charged according to the second requested current value, and the second requested current value is continuously reduced at a second set current reduction rate until the second requested current value reaches a first set current value. Then, the battery to be charged is charged with the second set current value until the highest voltage value of a single cell of the battery to be charged equals the cutoff voltage value, thus ending the charging process of the battery to be charged. Wherein, the highest voltage value of a single cell is the highest voltage value corresponding to the smallest battery unit included in the battery to be charged.

3. The method according to claim 1, characterized in that, The power-off duration is the length of time from the last time the battery was disconnected from the power source until the start of charging. The step of determining the initial SOC value of the battery to be recharged based on the received voltage signal of the battery to be recharged and the power-off duration of the battery to be recharged includes: If the power-down duration is longer than the set duration, the initial SOC value corresponding to the collected voltage signal is determined by the pre-established correspondence between the voltage signal and the SOC value. If the power-off duration is less than or equal to the set duration, then the SOC value of the battery to be charged at the last time it was disconnected from the power source is read, and the SOC value at the last time it was disconnected from the power source is used as the initial SOC value.

4. The method according to claim 1, characterized in that, The step of determining the requested current value for the initial set period based on the health state coefficient of the battery to be charged, the initial temperature, the initial SOC value, the initial terminal voltage value, and the maximum SOC value corresponding to the charging range in which the initial SOC value is located includes: The initial charging rate is determined based on the pre-established SOC value and the correspondence between temperature, SOC value and charging rate. The first initial requested current value is determined based on the initial charging rate and the rated capacity of the battery to be charged; The second initial requested current value is determined based on the initial open-circuit voltage value and the terminal voltage value corresponding to the maximum stage SOC value in the charging interval where the initial SOC value is located. The third initial requested current value is determined based on the initial SOC value and the maximum stage SOC value corresponding to the charging interval in which the initial SOC value is located. The request current value for the initial set period is determined based on the first initial request current value, the second initial request current value, the third initial request current value, and the health status coefficient.

5. The method according to claim 4, characterized in that, The step of determining the third initial requested current value based on the initial SOC value and the maximum stage SOC value corresponding to the charging interval in which the initial SOC value is located includes: Based on the charging range in which the initial SOC value is located, determine the charging time corresponding to the charging range in which the initial SOC value is located; A first intermediate value is determined by the ratio between the product of the coulombic efficiency and the charging time, and the product of a set value and the maximum available rated capacity of the battery to be charged. The second intermediate value is determined based on the difference between the initial SOC value and the maximum stage SOC value corresponding to the charging interval in which the initial SOC value is located. The third initial requested current value is determined based on the ratio of the second intermediate value to the first intermediate value.

6. A battery charging device, characterized in that, include: Current determination unit and charging unit: The current determination unit is used to determine the initial SOC value of the battery to be charged based on the received voltage signal of the battery to be charged and the power-off time of the battery to be charged if the current set period is the initial set period, and to use the initial SOC value as the current SOC value of the battery to be charged. The initial terminal voltage value of the battery to be charged received is used as the open circuit voltage value corresponding to the current SOC value, and the initial temperature of the battery to be charged received is used as the temperature value corresponding to the current SOC value. The requested current value for the initial set period is determined based on the health status coefficient of the battery to be charged, the initial temperature, the initial SOC value, the initial terminal voltage value, and the maximum SOC value corresponding to the charging range in which the initial SOC value is located. The charging range is determined based on the material properties of the battery to be charged; If the current set period is a set period other than the initial set period, then the current SOC value is determined based on the initial SOC value and the charging current in the current set period collected by the acquisition unit. Based on the health status coefficient of the battery to be charged, the temperature value corresponding to the current SOC value, the open circuit voltage value corresponding to the current SOC value, the current SOC value, and the maximum SOC value corresponding to the charging range in which the current SOC value is located, the requested current value for the current set period is determined. The charging unit is configured to control the charging unit to charge the battery to be charged within the current set period according to the determined requested current value.

7. A battery charging system, characterized in that, include: The system includes a data acquisition unit, a communication unit, a control unit, and a charging unit. The acquisition unit is used to acquire the voltage signal, charging current and temperature value of the battery to be charged, and send the voltage signal, charging current and temperature value of the battery to be charged to the control unit; The charging unit is used to send a charging request message to the control unit and receive a charging message sent by the control unit to charge the battery to be charged. The control unit is used to receive the voltage signal, charging current and temperature value of the battery to be charged sent by the acquisition unit, and to receive the charging request message sent by the charging unit, and to execute the method described in any one of claims 1 to 5. The communication unit is used for communication between the acquisition unit and the control unit, and for communication between the charging unit and the control unit.

8. An electronic device, characterized in that, It includes a memory and a processor, wherein a computer program is mounted on the memory and can run on the processor, and when the computer program is executed by the processor, it implements the method of any one of claims 1 to 5.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by the processor, it implements the method described in any one of claims 1 to 5.

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