Battery system charging method and device and readable storage medium

Abstract

The invention discloses a battery system charging method and device and a computer readable storage medium, and the method comprises the steps: determining an electric quantity interval where the electric quantity of a battery is located; when the electric quantity interval is a first electric quantity interval, controlling the battery to execute a first charging task according to a current step mode; when the electric quantity interval is a second electric quantity interval, controlling the battery to execute a second charging task according to a constant power mode; wherein the first electric quantity interval is lower than and not overlapped with the second electric quantity interval. By adopting the current step and constant power mode in different electric quantity intervals, the charging efficiency and the service life of the battery are considered, and the problems of long charging time caused by constant current in the whole process and polarization aggravation caused by the constant current step can be avoided.

Description

Technical Field

[0001] The present application relates to the field of electric power, and in particular to a battery system charging method, device, and readable storage medium. Background Art

[0002] After lithium-ion batteries are assembled into automotive power systems, the current widely used continuous charging methods in the industry mainly include full-range constant-current charging and full-range constant-current step charging at different SOC (state of charge) intervals. Although the full-range constant-current charging process is simple, it always charges at a lower current, resulting in a longer charging time, affecting the user's actual vehicle experience. While SOC interval constant-current step charging can shorten the charging time, the use of current steps in different SOC intervals can easily cause battery polarization, including ohmic internal resistance and electrochemical polarization problems, resulting in a rapid increase in the battery system's state of charge, exacerbating battery cell aging, and thus affecting the battery's service life and safety. Summary of the Invention

[0003] The present application provides a battery system charging method, device and readable storage medium to solve the technical problems of low charging efficiency, severe polarization during the charging process and shortened battery life in the related art.

[0004] This application adopts the following technical solution.

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

[0006] Determine the battery power range;

[0007] When the power range is the first power range, controlling the battery to perform the first charging task according to the current step mode;

[0008] When the power range is the second power range, controlling the battery to perform the second charging task in a constant power mode;

[0009] The first power range is lower than and does not overlap with the second power range.

[0010] In this way, the present application takes into account both charging efficiency and battery life by adopting current steps and constant power modes in different power ranges: in the charging process, the current step mode is adopted in the lower power range (first power range) to increase the charging speed and shorten the charging time; in the higher power range (second power range), the constant power mode is adopted to avoid the problems of long charging time caused by constant current throughout the process and aggravated polarization caused by constant current steps, thereby ensuring battery life and safety.

[0011] In conjunction with the first aspect, in one possible implementation, the method further includes:

[0012] When the power range is the third power range, controlling the battery to perform the third charging task according to the pulse charging mode;

[0013] The second power range is lower than and does not overlap with the third power range.

[0014] In this way, the present application introduces pulse charging in a higher power range (the third power range), which is beneficial to further reduce the degree of battery polarization, effectively improve the safety of the battery at the end of charging and increase the battery life.

[0015] With reference to the first aspect, in one possible implementation, the first power interval is composed of multiple first sub-intervals, the current step mode is configured with a step current parameter, the step current parameter includes multiple charging currents corresponding to the multiple first sub-intervals, and the charging current corresponding to the first sub-interval with a higher power level is less than the charging current corresponding to the first sub-interval with a lower power level;

[0016] Controlling the battery to charge according to the current step mode includes: taking the charging current corresponding to the first sub-interval into which the battery power falls as the target current, and controlling the battery to charge with the target current.

[0017] The charging current in different first sub-intervals is set so that the charging current corresponding to the first sub-interval with a higher charge is smaller than the charging current corresponding to the first sub-interval with a lower charge, that is, the charging current is gradually reduced as the charge increases. This can reduce the charging intensity when the battery is close to a full charge, and prevent the battery from being subjected to a large current load when the charge is high, thereby effectively protecting the battery, extending the battery life, and improving the safety and reliability of the battery.

[0018] In combination with the first aspect, in one possible implementation, the method further includes: obtaining the temperature of the battery; wherein, the step current parameters of the current step mode in the first charging task and the charging power of the constant power mode in the second charging task are respectively determined by the obtained temperature.

[0019] In this way, by adjusting the step current parameters of the current step mode or the charging power of the constant power mode in real time according to the battery temperature, it can accurately adapt to the charging needs of the battery at different temperatures, ensuring that the battery charging process is safer, more efficient and stable.

[0020] In conjunction with the first aspect, in one possible implementation, the first power interval is composed of multiple first sub-intervals, and the second power interval is composed of multiple second sub-intervals; the method further includes pre-performing the following pre-processing tasks:

[0021] Calibrate the battery's charging current corresponding to each first sub-interval and the charging current corresponding to each second sub-interval at different temperatures;

[0022] For each temperature: based on the calibrated charging current corresponding to each first sub-interval at the current temperature, the step current parameters of the first power interval at the current temperature are obtained; based on the calibrated charging current corresponding to each second sub-interval, the power corresponding to each second sub-interval is obtained, and the maximum power is selected as the charging power of the second power interval at the current temperature.

[0023] In this way, the present application achieves optimal matching of charging parameters through joint calibration of temperature and power, suppresses polarization effect, and enhances charging adaptability and battery cell health management capabilities.

[0024] In combination with the first aspect, in one possible implementation, the preprocessing task also includes: storing the obtained step current parameters of the first power interval and the charging power of the second power interval in the form of a data table; the method also includes: determining the power interval in which the battery is located, as well as the step current parameters of the current step mode in the first charging task or the charging power of the constant power mode in the second charging task by looking up the data table.

[0025] In this way, the appropriate charging control parameters are quickly determined by table lookup, which improves the control efficiency of the charging process while reducing the computational burden of the system and improving the response speed and reliability of the method.

[0026] In combination with the first aspect, in one possible implementation, the method further includes: correcting the charging current and charging power according to the health status of the battery.

[0027] In this way, the charging current and charging power can be corrected in real time according to the battery's health status, which can effectively adapt to battery aging and performance degradation, and further ensure the safe, reliable and efficient operation of the battery throughout its life cycle.

[0028] With reference to the first aspect, in a possible implementation, the first power range is 0%-90%, and the second power range is 90%-100%.

[0029] In this way, by reasonably dividing the power intervals, the charging speed and battery health protection can be effectively balanced during the actual charging process, ensuring fast charging and long-term reliability of the battery.

[0030] In a second aspect, the present application provides a battery system charging device, comprising a memory and a processor, wherein the memory is used to store computer programs or instructions; when the computer program or instructions are executed by the processor, any one of the methods in the above-mentioned first aspect implementation is implemented.

[0031] In a third aspect, the present application provides a computer-readable storage medium, in which a computer program or instruction is stored. When the computer program or instruction is executed by a processor, any method in the above-mentioned first or second aspect embodiments is implemented.

[0032] The beneficial effects of the second to third aspects above can be referred to the first aspect or any possible implementation of the first aspect, and will not be described in detail here. Based on the implementations provided in the above aspects, this application can also be further combined to provide more implementations.

[0033] Other advantages, objectives and features of the present application will be reflected in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0035] Figure 1 This is one of the flow charts of the battery system charging method of the present application;

[0036] Figure 2 This is the second flow chart of the battery system charging method of this application;

[0037] Figure 3 It is the flowchart of the preprocessing task;

[0038] Figure 4 This is a schematic diagram of the charging process of a lithium iron phosphate battery under a step-charging mode at 25°C;

[0039] Figure 5 Schematic diagram of the charging process of a lithium iron phosphate battery using the charging method of the present application at 25°C;

[0040] Figure 6 This is a comparison chart of the effects before and after the current / power correction based on SOH in this application;

[0041] Figure 7 This is the third flow chart of the battery system charging method of this application;

[0042] Figure 8 This is the battery system charging device of this application. DETAILED DESCRIPTION

[0043] It should be noted that, in this application, words such as "exemplary" or "as an example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described in this application as "exemplary" or "as an example" should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "as an example" is intended to present the relevant concepts in a concrete manner.

[0044] As used in this application, terms containing ordinal numbers, such as "first" and "second," may be used to describe various components. "Multiple" refers to two or more components. However, these components are not limited by these terms. The purpose of using these terms is solely to distinguish one component from other components and should not be understood to indicate or imply relative importance. As an example, without departing from the scope of this application, a first component may be named a second component, and similarly, a second component may be named a first component.

[0045] Before introducing the embodiments of the present application, the background technology involved in the present application is first introduced.

[0046] After lithium-ion batteries are assembled into automotive power systems, the current widely used continuous charging methods in the industry mainly include full-range constant-current charging and full-range constant-current step charging at different SOC intervals. Although the full-range constant-current charging process is simple, the low current used throughout the charging process results in a longer charging time, which affects the user's actual vehicle experience. While SOC interval constant-current step charging can shorten the charging time, the use of current steps in different SOC intervals can easily induce battery polarization, including ohmic internal resistance and electrochemical polarization, causing the battery system's state of charge to rise rapidly, exacerbating battery cell aging, and thus affecting the battery's service life and safety. These charging methods have a clear trade-off between efficiency, lifespan, and polarization effects, becoming one of the main bottlenecks in current power lithium battery charging technology.

[0047] To sum up, in order to solve the technical problems in the related technologies such as low charging efficiency, severe polarization during the charging process, shortened battery life and insufficient charging safety in the high SOC section, the present application provides a battery system charging method and a computer-readable storage medium. Before introducing the embodiments of the method of the present application, an exemplary application scenario is first described, which can more conveniently and clearly understand the functions and intentions of the various implementation methods in the embodiments of the method of the present application.

[0048] refer to Figure 1 , Figure 1 This is one of the flow charts of the battery system charging method provided in the embodiment of the present application. The battery system charging method of the present application includes:

[0049] S101: Determine the power range of the battery;

[0050] The battery is not limited and can be, for example, a lithium-ion power battery.

[0051] Capacity refers to the available electrical energy stored in the battery at the current moment, which can be expressed as a percentage of its maximum capacity (most common) or an absolute value (such as kilowatt-hour kWh).

[0052] In a charging scenario, a battery's charge typically refers to the ratio of the battery's currently stored available energy to the maximum energy it can store when fully charged. It's usually expressed as a percentage to more intuitively reflect the battery's current state of charge (SOC). For example, a 0% charge indicates that the battery is completely discharged and has no available capacity; a 100% charge indicates that the battery is fully charged and has reached its rated capacity; and a 50% charge indicates that the battery currently stores half its rated capacity.

[0053] A battery interval is a range of battery levels. If the battery level is expressed as a percentage, the battery interval is a specific range within that percentage, such as 10%-40%, 40%-70%, or 70%-100%.

[0054] In this embodiment, the entire power range (0-100%) is pre-divided into two ranges: a first power range and a second power range. The first power range is lower than and does not overlap with the second power range, that is, the first power range is a low power range and the second power range is a high power range.

[0055] For example, the first power range is 0%-90%, and the second power range is 90%-100%. This means that when the battery power is detected to be within the range of 0%-90%, it is determined to be in the first power range; when the battery power is detected to be within the range of 90%-100%, it is determined to be in the second power range. For example, if the battery power is 30%, it falls within the range of 0%-90%, and the battery power is determined to be in the first power range. If the battery power is 95%, it falls within the range of 90%-100%, and the battery power is determined to be in the second power range.

[0056] It should be noted that the specific ranges of the first power range and the second power range can be adjusted according to actual conditions.

[0057] S103: When the power range is the first power range, controlling the battery to perform a first charging task in a current step mode;

[0058] The current step mode divides the charging process into multiple power intervals (SOC intervals) and uses different constant current charging currents in different power intervals.

[0059] It can be seen that in this embodiment, when the battery is in a lower power range, the battery is controlled to be charged according to the current step mode (ie, the charging current used for constant current charging is gradually adjusted according to different SOC stages) to optimize the charging efficiency and ensure battery safety.

[0060] S105: When the power range is the second power range, controlling the battery to perform the second charging task in a constant power mode;

[0061] That is, in a higher power range, the battery is controlled to charge in constant power mode, that is, the charging power is kept constant. This can avoid the problems of long charging time caused by constant current throughout the process and increased polarization caused by constant current steps, thereby ensuring battery life and safety.

[0062] It is understandable that each flow chart of the present application only shows the process of one method cycle. In fact, the controller periodically executes the method process of the flow chart during the charging process. In this way, during the entire charging process of this embodiment, the present application adopts the current step mode charging in the lower power range (first power range) during the charging process to increase the charging speed and shorten the charging time; in the higher power range (second power range), the constant power mode charging is adopted to avoid the problem of long charging time caused by constant current throughout the process and aggravated polarization caused by constant current steps; ultimately, it achieves a balance between charging efficiency and battery life.

[0063] In some embodiments, the first power interval is composed of multiple first sub-intervals, and each first sub-interval corresponds to a specific power range. It should be noted that there is no limit on the number of first sub-intervals, and the interval lengths of different first sub-intervals can be equal or different. In some embodiments, of any two different first sub-intervals, the interval length of the relatively lower first sub-interval is greater than the interval length of the relatively higher first sub-interval. For example, the first power interval is 0%-90%, which can be divided into two first sub-intervals: 0%-80% and 80%-90%.

[0064] The current step mode is configured with step current parameters, which include multiple charging currents corresponding to multiple first sub-intervals; the charging current corresponding to the first sub-interval with higher power is smaller than the charging current corresponding to the first sub-interval with lower power.

[0065] Accordingly, controlling the battery to charge according to the current step mode includes: taking the charging current corresponding to the first sub-interval into which the power falls as the target current, and controlling the battery to charge with the target current.

[0066] That is, in the current step mode, each first sub-interval is constant current charging. The difference between different first sub-intervals is that the charging current during constant current charging is different. Moreover, because the charging current corresponding to the first sub-interval with higher power is less than the charging current corresponding to the first sub-interval with lower power, the charging current is gradually reduced as the power increases. This can reduce the charging intensity when the battery is close to being fully charged, and avoid the battery being subjected to a large current load when the power is high, thereby effectively protecting the battery, extending the battery life, and improving the safety and reliability of the battery.

[0067] refer to Figure 2 In some embodiments, considering the impact of temperature on charging, the step current parameters of the current step mode and the charging power of the constant power mode are configured to be related to the temperature. Therefore, the step current parameters of the current step mode and the charging power of the constant power mode related to the temperature are prepared in advance, and the corresponding charging method includes:

[0068] S201: Obtaining the battery temperature;

[0069] The temperature of the battery may be the collected temperature of the environment in which the battery is located, or the collected temperature inside the battery.

[0070] S203: When the battery level is in the first battery level range, controlling the battery to perform a first charging task in a current step mode, wherein a step current parameter of the current step mode in the first charging task is determined by the acquired temperature;

[0071] S205: When the power range is the second power range, determining a charging power in a constant power mode in a second charging task according to the acquired temperature, wherein the charging power in the constant power mode in the second charging task is determined by the acquired temperature;

[0072] That is, the step current parameter of the current step mode in the first charging task and the charging power of the constant power mode in the second charging task are respectively determined by the acquired temperature.

[0073] It should be noted that step S201 of obtaining the battery temperature can be executed once each time charging is started, and no longer executed during the charging process. During the charging process, only S101-S205 need to be executed periodically; of course, in some embodiments, step S201 of obtaining the battery temperature can also be to periodically obtain the temperature during the charging process (the step current parameters and charging power are also synchronously updated periodically). The period of temperature acquisition can be consistent with the execution period of the entire method, or it can be an integer multiple of the method period, that is, the temperature update is slower.

[0074] In this way, by considering the temperature effect during the charging process and selecting the appropriate charging current or charging power, it is possible to accurately adapt to the charging needs of the battery at different temperatures, ensuring that the battery charging process is safer, more efficient and stable.

[0075] In some embodiments, the method further includes pre-processing the following tasks to determine the step current parameters of the current step mode related to temperature and the charging power of the constant power mode related to temperature. In this embodiment, the first power interval is composed of multiple first sub-intervals, and the second power interval is composed of multiple second sub-intervals. Figure 3 , the preprocessing tasks include:

[0076] S301: Calibrate the charging current corresponding to each of the first sub-intervals and the charging current corresponding to each of the second sub-intervals of the battery at different temperatures;

[0077] Specifically, at each target temperature, a charging current applicable to each first subinterval and a charging current applicable to each second subinterval are determined.

[0078] For example, calibration can be based on the voltage relaxation method. The voltage relaxation method refers to the method of monitoring the voltage change during the charging process of the battery at a certain charge rate. If lithium dendrites occur on the negative electrode surface, it will cause the subsequent voltage recovery process to change.

[0079] For example, the relaxation voltage method can be used to calibrate the appropriate charging current for a single cell at different temperatures (-10°C to 60°C) and different SOCs (0% to 100% SOC). This is equivalent to obtaining a current step-based continuous charging table for the full temperature range of 0% to 100% SOC, as shown in Table 1. It should be understood that the temperatures in Table 1 are discrete, and the intervals between adjacent temperatures can be fixed or variable.

[0080] Table 1 Current step continuous charging table at 0% to 100% SOC in full temperature field

[0081]

[0082] In Table 1, C (rate) is the unit of charging current. 1C means full charging in 1 hour, and 0.8C means charging at 80% of the rated current.

[0083] S303: For each temperature: based on the charging current corresponding to each first sub-interval at the calibrated current temperature, obtain the step current parameters of the first power interval at the current temperature; based on the charging current corresponding to each second sub-interval at the calibrated current temperature, obtain the power corresponding to each second sub-interval, and select the maximum power as the charging power of the second power interval at the current temperature.

[0084] Among the six power intervals in Table 1, the first two can be recorded as the first sub-intervals (0-80%], (80-90%], and the following four can be recorded as the second sub-intervals (90-95%], (95-98%], (98-99%], (99-100%]. That is, the final remaining step current parameters include the two columns (0-80%], (80-90%] in Table 1, and for (90-95%], (95-98%], (98- The four columns of data (99%], (99-100%]) are used to further carry out constant current charging experiments and measure the actual charging power of each second sub-interval during the constant current charging process. Then, the maximum value is selected from the charging power of all second sub-intervals as the constant power charging parameter of the second power interval at the current temperature. That is, the charging power is converted from the four columns of data (90-95%], (95-98%], (98-99%], and (99-100%] in Table 1.

[0085] Taking lithium iron phosphate batteries at 25°C as an example, 0.8C, 0.6C, 0.6C, and 0.5C can be used to obtain the corresponding powers of (90-95%), (95-98%), (98-99%), and (99-100%) through constant current charging experiments, and the maximum power is selected as the charging power of the second power range at the current temperature, as shown in 0.8P in Table 2.

[0086] Table 2 Comparison of different charging standards for lithium iron phosphate batteries at 25°C

[0087]

[0088] In Table 2, P (power rate): how many times the rated power is used for charging, for example, 0.8P means charging at 80% of the rated power. Upper limit voltage: the maximum voltage reached during charging, in volts (V).

[0089] Charging time: The total time required to complete the charging task, in minutes (min).

[0090] Can be combined with Table 2, Figure 4 and Figure 5 ( Figure 4 and Figure 5 The middle dotted line is the current curve, the solid line is the voltage curve, the horizontal axis represents SOC, the left vertical axis represents voltage, and the right vertical axis represents current). The current step charging scheme under 0% to 100% SOC in the full temperature field can be clearly compared with the step charging + constant power charging scheme of this application.

[0091] As shown in Table 2, the step-charging method divides the SOC (battery charge percentage) into six ranges, with different charging currents applied to each range. For example, when the SOC is 0-80%, the battery is charged at a current of 1C; from 80-95%, at 0.8C; from 95-99%, at 0.6C; and from 99-100%, at 0.5C. The upper voltage limit is 3.65V, and the total charging time is 55.9 minutes.

[0092] Step Charging + Constant Power Charging: 1C charging current is used in the first range (SOC 0-80%), and 0.8P constant power is used in the second range (SOC 90-100%). The upper voltage limit during charging is 3.65V, and the total charging time is 54.1 minutes (based on an ambient temperature of 25°C).

[0093] During actual charging, if the ambient temperature is detected to be 25°C, the system automatically applies the pre-processed parameters: From 0% to 90%, a step-charging mode is used, such as 1C and 0.8C. When the SOC reaches 90% to 100%, the system switches to a constant-power charging mode at 0.8P, automatically adjusting the charging current to maintain a constant charging power output. It should be noted that all data in Table 2 was obtained at a normal temperature of 25°C. These data primarily reflect charging performance at normal temperatures; in actual applications, these parameters may vary under different ambient temperatures. Essentially, each temperature has a corresponding data set for the step-charging + constant-power charging mode in Table 2. If the ambient temperature changes, such as dropping to 0°C, the system automatically uses the data from 0°C to dynamically adjust the charging current and power parameters for each range, thereby ensuring both battery charging safety and improving charging efficiency.

[0094] from Figure 4 and Figure 5 It is not difficult to see that if the step charging system is adopted throughout the process, although the charging current can be adjusted in a targeted manner in different SOC intervals, in the high SOC interval, due to the gradual decrease in charging current, the overall charging efficiency still has room for improvement. The step charging + constant power charging system proposed in this application adopts constant power charging in the high SOC interval, which not only smoothly reduces the current and reduces the voltage step polarization, but also effectively improves the charging efficiency in the high SOC interval, and significantly shortens the overall charging time, achieving better charging performance. Compared with the existing technology, the charging strategy of this application can further improve the charging speed and user experience on the basis of ensuring safety and battery life.

[0095] In some specific embodiments, the preprocessing task also includes the following: storing the step current parameters of the first power interval (i.e., the charging current values ​​corresponding to different SOC sub-intervals) and the charging power parameters of the second power interval (i.e., the maximum safe charging power in constant power mode) obtained through experiments in the form of a data table.

[0096] Correspondingly, the method further includes: determining the battery charge range and the step current parameters of the current step mode in the first charging task or the charging power of the constant power mode in the second charging task by looking up the data table.

[0097] In this way, the appropriate charging control parameters are quickly determined by table lookup, which improves the control efficiency of the charging process while reducing the computational burden of the system and improving the response speed and reliability of the method.

[0098] It can be understood that when looking up the table, if the current temperature is T0, which is not among the temperatures recorded in the table, the simplest method is to directly find the temperature T1 in the table that is closest to the current temperature T0, and then directly read the data D(T1) under T1, and determine the current or power corresponding to the SOC from the data D(T1); the current and power corresponding to the current temperature T0 can also be determined by linear interpolation. For example, if the current temperature falls between T1 and T2 in the table, the data D(T1) of T1, the data D(T0), and the data D(T2) of T2 can be linearly processed. For example, assuming that in a certain SOC interval, the power in D(T1) is P1, the power in D(T0) is P0, and the power in D(T2) is P2, then (P1-P0) / (T1-T0)=(P0-P2) / (T0-T2), and P0 is calculated accordingly. The process of determining the current is the same.

[0099] In some embodiments, the method further includes dynamically modifying the charging current or charging power based on the battery's health status (e.g., cycle count, internal resistance, temperature, etc.). Specifically, the system detects the battery's health status and, based on preset modification rules, adjusts the original charging current or power parameters to better balance battery life and charging safety.

[0100] For example, when the system detects a high number of battery cycles or an increase in internal resistance, it will appropriately reduce the charging current or charging power to slow down battery performance degradation. Alternatively, when the battery temperature is high, the system will adjust the charging parameters accordingly to prevent safety risks caused by overheating. For example, the allowable charging current under certain SOC ranges and temperature conditions is 50A. However, if the battery internal resistance is detected to be elevated, the system will adjust the charging current down to 40A based on the correction rules, effectively protecting the battery's health and extending its service life. This dynamic correction process can also be performed in real time, ensuring the most appropriate charging strategy is adopted under different health conditions.

[0101] For example, see Figure 6 The researchers conducted a cycle life comparison test, using the variable of whether the current / power was adjusted according to the SOH (state of health) or not, until the battery SOH dropped to 80% (i.e., the end of the life cycle). The results showed that compared with no correction, the battery capacity retention rate increased by 3% when the current / power was dynamically adjusted according to the SOH.

[0102] In this way, the charging strategy is dynamically adjusted based on battery health parameters, effectively avoiding overcharging and aging problems, and improving the reliability and service life of the battery system.

[0103] In some embodiments, reference Figure 7 , the method further comprises:

[0104] S701: When the power range is a third power range, control the battery to perform a third charging task according to the pulse charging mode;

[0105] In this embodiment, the full power range (0-100%) is pre-divided into three ranges: a first power range, a second power range, and a third power range. The first power range is lower than and does not overlap with the second power range, and the second power range is lower than and does not overlap with the third power range.

[0106] For example, the first power interval is 0%-90%, the second power interval is 90%-95%, and the third power interval is 95%-100%. This means that when the battery power is detected to be in the range of 0%-90%, it is determined that the power interval is the first power interval; when the battery power is detected to be in the range of 90%-95%, it is determined that the power interval is the second power interval; when the battery power is detected to be in the range of 95%-100%, it is determined that the power interval is the third power interval. For example, if the battery power is 30%, it falls within the range of 0%-90%, and the battery power is determined to be in the first power interval; if the battery power is 93%, it falls within the range of 90%-95%, and the battery power is determined to be in the second power interval; if the battery power is 98%, it falls within the range of 95%-100%, and the battery power is determined to be in the second power interval.

[0107] It should be noted that the specific ranges of the first power range, the second power range, and the third power range can be adjusted according to actual conditions.

[0108] Pulse charging mode means that when charging the battery, instead of continuously applying a constant current or constant voltage to the battery, the battery is charged periodically in a "pulse" manner, that is, a charging current (charging pulse) is applied to the battery for a period of time, followed by a pause for a period of time (intermission), and then charging is continued, and this cycle is repeated until charging is completed.

[0109] Specifically, the pulse charging mode includes the following features:

[0110] Charging stage (pulse stage): The battery is charged at a higher current (or set current) for a short time.

[0111] Rest phase (intermittent phase): Stop charging to give the battery time to "rest", the current is zero, and the ion diffusion and electrochemical reaction inside the battery can be relieved and balanced.

[0112] Repeated cycle: The charging and resting processes are continuously alternated to form a pulsed charging waveform.

[0113] The purpose of pulse charging is to help reduce the polarization effect, improve battery charging efficiency and capacity utilization; reduce battery temperature rise and extend battery life; reduce gassing and crystallization and improve safety.

[0114] As an example, the pulse charging mode can be set as follows: charge for 10 seconds, stop for 2 seconds, then charge for 10 seconds, and repeat.

[0115] In this way, the present application introduces pulse charging in a higher power range (the third power range), which is beneficial to further reduce the degree of battery polarization, effectively improve the safety of the battery at the end of charging and increase the battery life.

[0116] See also Figure 8 In a second aspect, the present application provides a battery system charging device, comprising a memory and a processor, wherein the memory is used to store computer programs or instructions; when the computer program or instructions are executed by the processor, any method in the above-mentioned first aspect implementation is implemented.

[0117] In a third aspect, the present application provides a computer-readable storage medium, in which a computer program or instruction is stored. When the computer program or instruction is executed by a processor, any method in the above-mentioned first or second aspect embodiments is implemented.

[0118] It should be noted that the order of description of the embodiments of the present application does not limit the priority order of the embodiments.

[0119] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the art to which this application belongs. The terms used in this application and in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0120] It should be noted that the “connected” or “connected” mentioned in this application, unless otherwise specified, not only includes directly connecting two entities, but also includes indirectly connecting through other entities with beneficial improvement effects.

[0121] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims. All equivalent transformations made by using the contents of the description and drawings of this application under the inventive concept of this application, or direct / indirect application in other related technical fields are included in the scope of patent protection of this application.

Claims

1. A battery system charging method, characterized in that: include: Determining a power range of the battery; When the power range is the first power range, controlling the battery to perform a first charging task in a current step mode; When the power range is the second power range, controlling the battery to perform the second charging task in a constant power mode; The first power range is lower than and does not overlap with the second power range.

2. The battery system charging method according to claim 1, characterized in that: The method further comprises: When the power range is the third power range, controlling the battery to perform a third charging task in a pulse charging mode; The second power range is lower than and does not overlap with the third power range.

3. The battery system charging method according to any one of claims 1 to 2, characterized in that: The first charge interval is composed of a plurality of first sub-intervals, the current step mode is configured with a step current parameter, the step current parameter includes a plurality of charging currents corresponding to the plurality of first sub-intervals, the charging current corresponding to the first sub-interval with a higher charge is smaller than the charging current corresponding to the first sub-interval with a lower charge; The controlling the battery to be charged in a current step mode includes: taking the charging current corresponding to the first sub-interval into which the battery power falls as a target current, and controlling the battery to be charged with the target current.

4. The battery system charging method according to any one of claims 1 to 3, characterized in that: The method further includes: obtaining the temperature of the battery; The step current parameter of the current step mode in the first charging task and the charging power of the constant power mode in the second charging task are respectively determined by the acquired temperature.

5. The battery system charging method according to claim 4, characterized in that: The first power interval is composed of a plurality of first sub-intervals, and the second power interval is composed of a plurality of second sub-intervals; The method further includes performing the following pre-processing tasks in advance: Calibrate the charging current corresponding to each of the first sub-intervals and the charging current corresponding to each of the second sub-intervals of the battery at different temperatures; For each temperature: obtaining the step current parameter of the first charge interval at the current temperature based on the charging current corresponding to each of the first sub-intervals at the calibrated current temperature; Based on the calibrated charging currents corresponding to the respective second sub-intervals, the powers corresponding to the respective second sub-intervals are obtained, and the maximum power is selected as the charging power for the second power interval at the current temperature.

6. The battery system charging method according to claim 5, characterized in that: The pre-processing task further includes: storing the obtained step current parameters of the first power range and the charging power of the second power range in the form of a data table; The method also includes: determining the power range of the battery power and the step current parameters of the current step mode in the first charging task or the charging power of the constant power mode in the second charging task by checking the data table.

7. The battery system charging method according to claim 6, characterized in that: The method further includes: correcting the charging current and the charging power according to the health status of the battery.

8. The battery system charging method according to claim 1, wherein: The first power range is 0%-90%, and the second power range is 90%-100%.

9. A battery system charging device, characterized in that: The method comprises a memory and a processor, wherein the memory is used to store computer programs or instructions; when the computer program or instructions are executed by the processor, the method according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium, characterized in that The storage medium stores a computer program or instruction, and when the computer program or instruction is executed by a processor, the method according to any one of claims 1 to 8 is implemented.

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