Intelligent charging method

Abstract

The embodiment of the present application relates to the technical field of battery charging, in particular to a kind of intelligent charging method, applied to charger, and the target battery is electrically connected with charger.The embodiment of the present application calculates relative reference voltage according to the reference voltage of target battery, and obtains charging cut-off voltage and charging maintenance voltage according to the reference temperature and reference health degree of target battery, to flexibly determine reasonable and safe charging strategy according to relative reference voltage, charging cut-off voltage and charging maintenance voltage, which can safely, reasonably and flexibly charge target battery based on charging strategy, and is suitable for battery with different charging parameters, charging environment, type and state, significantly improves the flexibility and safety of battery charging.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of battery charging, in particular to an intelligent charging method. BACKGROUND

[0002] Lead-acid batteries are widely used in electric bicycles, electric tricycles, energy storage systems, automotive starting (SLI), uninterruptible power supplies (UPS), and various types of backup power supplies due to their relatively low cost, mature technology, high reliability, good high-current discharge performance, and high recycling rate.

[0003] In related technologies, the mainstream intelligent charging method for lead-acid batteries is CC-CV (constant current + constant voltage charging). The specific charging process is as follows: first, charge with a large constant current to a specified voltage (to increase the charging speed), and then switch to constant voltage charging. The characteristic of constant current and constant voltage charging is to use fixed voltage and current, for example, the common 48V 3A charging adapter for electric bicycles. However, this constant current and constant voltage charging method has fixed parameters, poor adaptability to battery charging environment, charging parameters, and battery state, which limits the charging flexibility, and the charging speed may be too fast or too slow, which can easily cause overcurrent, severe heating, excessive charging cutoff voltage, and other problems, reducing the safety of battery charging. SUMMARY

[0004] Therefore, an object of embodiments of the present application is to provide an intelligent charging method to improve the poor battery charging flexibility and low charging safety in related technologies.

[0005] To solve the above technical problems, embodiments of the present application provide the following technical solutions:

[0006] In a first aspect, embodiments of the present application provide an intelligent charging method applied to a charger, the charger being electrically connected to a target battery, and the method comprising:

[0007] obtaining a reference voltage, a reference current, a reference temperature, and a reference health degree of the target battery, the reference voltage, the reference current, and the reference temperature being actual voltage, actual current, and actual temperature of the target battery during charging;

[0008] calculating a relative reference voltage of the target battery based on the reference voltage;

[0009] obtaining a charging cutoff voltage and a charging maintenance voltage of the target battery based on the reference temperature and the reference health degree;

[0010] determining a reference charging strategy of the target battery based on the relative reference voltage, the charging cutoff voltage, and the charging maintenance voltage, the reference charging strategy being used to represent a manner of adjusting current of the target battery during charging;

[0011] Charge the target battery based on the reference charging strategy.

[0012] The embodiment of the present application has the following beneficial effects: Compared with the prior art, the intelligent charging method provided by the embodiment of the present application is applied to a charger, the charger is electrically connected with a target battery, the method comprises the following steps: obtaining a reference voltage, a reference current, a reference temperature and a reference health degree of the target battery, the reference voltage, the reference current and the reference temperature are respectively an actual voltage, an actual current and an actual temperature of the target battery in a charging process, calculating a relative reference voltage of the target battery based on the reference voltage, obtaining a charging cutoff voltage and a charging maintenance voltage of the target battery based on the reference temperature and the reference health degree, determining a reference charging strategy of the target battery based on the relative reference voltage, the charging cutoff voltage and the charging maintenance voltage, the reference charging strategy is used to represent a manner of adjusting a current of the target battery in the charging process, and charging the target battery based on the reference charging strategy.

[0013] The embodiment of the present application calculates the relative reference voltage according to the reference voltage of the target battery, and obtains the charging cutoff voltage and the charging maintenance voltage according to the reference temperature and the reference health degree of the target battery, so that a reasonable and safe charging strategy is flexibly determined according to the relative reference voltage, the charging cutoff voltage and the charging maintenance voltage, the target battery can be safely, reasonably and flexibly charged based on the charging strategy, the method can be applied to batteries with different charging parameters, charging environments, types and states, and the flexibility and safety of battery charging are significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the prior art or the embodiments. Obviously, the drawings described below only show some embodiments of the present application, and should not be regarded as a limitation to the protection scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0015] Figure 1 is an application scenario diagram of the intelligent charging method provided by some embodiments of the present application;

[0016] Figure 2 is a flow diagram of the intelligent charging method provided by some embodiments of the present application;

[0017] Figure 3 is Figure 2 is a sub-flow diagram of step S43 in the intelligent charging method shown in the embodiment;

[0018] Figure 4 is Figure 2 is a sub-flow diagram of step S45 in the intelligent charging method shown in the embodiment;

[0019] Figure 5 FIG. 1 is a schematic diagram of a relationship curve between a voltage boost value of a target battery and a temperature and a charging rate, and a relationship curve between the voltage boost value of the target battery and the temperature and the charging rate when the target battery is in a preset voltage interval, according to some embodiments of the present application. DETAILED DESCRIPTION

[0020] In order to make the objects and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. The following detailed description of the embodiments of the present application in the drawings is not intended to limit the scope of the present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of the present application.

[0021] It should be noted that, if there is no conflict, each technical feature involved in the embodiments of the present application described below can be combined with each other, and all are within the scope of protection of the present application. In addition, although the functional modules are divided in the device or structure schematic diagram, and the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than the module division in the device or the order in the flowchart. In addition, the expressions "first", "second", "third" and other similar expressions used herein do not limit the data and execution order, but are only for the purpose of explanation and to distinguish the same or similar items with basically the same function and effect, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of technical features.

[0022] Unless otherwise defined, the technical terms and scientific terms used in the specification are the same as the meanings commonly understood by those skilled in the art to which the present application belongs. The terms used in the specification are only for the purpose of describing the specific embodiments and are not intended to limit the present application. It should be understood that the term "and / or" used in the specification includes any and all combinations of one or more listed items.

[0023] In the related art, the mainstream intelligent charging method for lead-acid batteries is CC-CV (constant current + constant voltage charging). The specific charging process is: first, constant current charging at a relatively large current to a specified voltage (to increase the charging speed), and then switching to constant voltage charging. The characteristic of constant current and constant voltage charging is to use fixed voltage and current, for example, the common 48V 3A charging adapter on electric bicycles.

[0024] The inventor found that the constant current and constant voltage charging method has at least the following limitations:

[0025] 1) Parameter fixation rigidity: no matter how large the capacity of the battery is, a fixed size current is adopted, the flexibility of charging is low, which leads to slow charging of large capacity batteries and fast charging of small capacity batteries;

[0026] 2) Poor environmental adaptability: no matter how the environmental temperature is, a fixed size current is adopted, which may lead to problems such as winter charging failure or fast charging end;

[0027] 3) Non-standard battery replacement is not allowed: the user is not allowed to replace a lower capacity single battery, because after replacing the lower capacity single battery, the charging current (i.e. charging rate) is larger, which is easy to cause problems such as overcurrent and serious heating, and the safety of battery charging cannot be guaranteed;

[0028] 4) Too many charging adapter models, and end users have difficulty in selection: charging adapter specifications have various total voltages and currents, such as 36V 3A, 48V 3A, 48V 2A, etc. Different specifications of charging adapters have different charging rates, and cannot be applied to different types of batteries;

[0029] 5) Ignoring the state difference of different batteries: for new batteries and aged batteries, full charge batteries and deeply discharged batteries, the acceptable charging current and charging cutoff voltage threshold are different, and constant current constant voltage charging is harmful to some batteries, which shortens the service life of the battery.

[0030] Therefore, the embodiments of the present application provide an intelligent charging method, which calculates a relative reference voltage according to a reference voltage of a target battery, and obtains a charging cutoff voltage and a charging maintenance voltage according to a reference temperature and a reference health degree of the target battery, so as to flexibly determine a reasonable and safe charging strategy according to the relative reference voltage, the charging cutoff voltage and the charging maintenance voltage, and to safely, reasonably and flexibly charge the target battery based on the charging strategy, which is suitable for batteries with different charging parameters, charging environments, types and states, and significantly improves the flexibility and safety of battery charging.

[0031] Please refer to Figure 1 , Figure 1 The application scenario of the intelligent charging method provided by some embodiments of the present application is schematically shown.

[0032] As shown in Figure 1 , the application scenario includes a charging system 1000, which includes a charger 100, a target battery 200 and a charging power supply 300. Among them, Figure 1 Only one target battery 200 is schematically shown, and in actual application, the number of target batteries 200 can be multiple.

[0033] The charger 100 is electrically connected with the target battery 200 and the charging power supply 300 respectively, the charging power supply 300 is configured to provide electric energy, the charger 100 is used for converting and adapting the electric energy output by the charging power supply 300, and outputting the converted and adapted electric energy to the target battery 200, so as to charge the target battery 200. After being electrically connected to the charging power supply 300 and the target battery 200, the charger 100 obtains a reference voltage, a reference current, a reference temperature and a reference health degree of the target battery 200, and calculates a relative reference voltage of the target battery 200 according to the reference voltage. The reference voltage, the reference current and the reference temperature are actual voltage, actual current and actual temperature of the target battery 200 in the charging process respectively.

[0034] In some embodiments, the charging cut-off voltage and the charging maintenance voltage of the target battery 200 are determined according to the reference temperature and the reference health degree. Then, the reference charging strategy of the target battery 200 is determined according to the relative reference voltage, the charging cut-off voltage and the charging maintenance voltage. Finally, the target battery 200 is charged according to the reference charging strategy, and the reference charging strategy is used to represent the way of adjusting the current of the target battery 200 in the charging process.

[0035] In the embodiments of the present application, the charger 100 can be various suitable types and specifications of charging adapters and the like, the target battery 200 can be a storage battery, a lithium battery, a nickel-hydrogen battery or any other suitable battery, and the charging power supply 300 can be a charging pile, a charging station, a charging management system or any other suitable type of system or platform. It can be understood that the charging control method provided by the embodiments of the present application is not limited to constant current and constant voltage charging, and the target battery 200 is charged by using a flexible, safe and reasonable charging strategy, which can be applied to batteries with different charging parameters, charging environments, types and states, and significantly improves the flexibility and safety of battery charging.

[0036] It should be understood that, Figure 1 The application scenarios shown are only illustrative of one situation in which the charger 100 charges the target battery 200 through the charging power supply 300 in some embodiments of the present application, but do not limit the structure, type and number of the charger 100, the charging power supply 300 and the target battery 200 in any other application scenarios or embodiments. For example, in some other application scenarios or embodiments, the number of target batteries 200 can be multiple, and the charger 100 charges multiple target batteries 200 through the charging power supply 300.

[0037] Hereinafter, the intelligent charging method provided by the embodiments of the present application will be described in detail, and the intelligent charging method can be applied to the above-mentioned charger (for example, the charger 100).

[0038] Please refer to Figure 2 ,Figure 2 A flowchart of the intelligent charging method provided by some embodiments of the present application is shown.

[0039] As shown in the figure, the intelligent charging method includes but is not limited to the following steps S41-S45: Figure 2

[0040] S41: Obtain the reference voltage, reference current, reference temperature and reference health degree of the target battery.

[0041] In the embodiments of the present application, the reference voltage, reference current and reference temperature are respectively the actual voltage, actual current and actual temperature of the target battery in the charging process.

[0042] In some embodiments, the target battery is configured with a voltage sampling circuit, a current sampling circuit and a temperature sensor, and the reference voltage, reference current and reference temperature of the target battery are respectively sampled and obtained by the voltage sampling circuit, the current sampling circuit and the temperature sensor.

[0043] In some embodiments, the reference health degree of the target battery is stored in a local storage of the charger, a server or a cloud, or any suitable storage medium or device, and the reference health degree of the target battery is obtained from the local storage, the server or the cloud.

[0044] S42: Calculate the relative reference voltage of the target battery based on the reference voltage.

[0045] In some embodiments, the relative reference voltage of the target battery is calculated based on the reference voltage, specifically including but not limited to the following steps S421-S422:

[0046] S421: According to the rounding rule, round off the quotient value obtained by dividing the reference voltage by a first preset value to obtain a reference quantity.

[0047] S422: Divide the product of the reference voltage and a second preset value by the reference quantity to obtain the relative reference voltage.

[0048] Wherein, the first preset value represents the rated voltage of the target battery, for example, 6V, 9V, 12V, etc.

[0049] For example, the first preset value is 6 and the second preset value is 2, and the relative reference voltage of the target battery is calculated according to the following formula: , In the above formula, is the reference voltage of the target battery, is the quotient value obtained by dividing the reference voltage by the first preset value, means rounding off calculation according to the rounding rule, is the reference quantity,​ is a product of the reference voltage and a second preset value, is a relative reference voltage.

[0050] S43: Obtain the charging cut-off voltage and the charging maintenance voltage of the target battery based on the reference temperature and the reference health degree.

[0051] In some embodiments, the reference temperature and the reference health degree are input into a pre-trained voltage model, and the charging cut-off voltage and the charging maintenance voltage of the target battery are calculated by using the voltage model, wherein the voltage model is a model for predicting the charging cut-off voltage and the charging maintenance voltage of the target battery according to the reference temperature and the reference health degree of the target battery.

[0052] In some embodiments, the reference temperature and the reference health degree are substituted into a fitted voltage function, and the charging cut-off voltage and the charging maintenance voltage of the target battery are calculated by using the voltage function, wherein the voltage function is a function representing the corresponding relationship between the charging cut-off voltage and the charging maintenance voltage of the target battery and the reference temperature and the reference health degree.

[0053] S44: Determine the reference charging strategy of the target battery based on the relative reference voltage, the charging cut-off voltage, and the charging maintenance voltage.

[0054] In this embodiment, the reference charging strategy is used to represent the way of adjusting the current of the target battery during the charging process, i.e., the strategy of adjusting the charging current of the target battery.

[0055] For example, before charging the target battery, the initial state of charge of the target battery is determined according to the relative reference voltage, and the reference charging strategy of the target battery is determined according to the initial state of charge.

[0056] For example, during the charging of the target battery, the real-time state of charge of the target battery is determined according to the relative reference voltage, the charging cut-off voltage, and the charging maintenance voltage, and the reference charging strategy of the target battery is determined according to the real-time state of charge.

[0057] In some embodiments, the reference charging strategy is a constant current charging, a constant voltage charging, or a strategy of adjusting the charging current in real time according to the charging parameters (such as internal resistance, charging voltage, charging time, etc.) of the target battery.

[0058] S45: Charge the target battery based on the reference charging strategy.

[0059] In some embodiments, when the reference charging strategy is a first reference strategy, the charging parameters (such as internal resistance, charging voltage, charging time, etc.) of the target battery are obtained in real time, the charging current of the target battery is adjusted in real time according to the charging parameters, and the target battery is charged with the charging current adjusted in real time.

[0060] In some embodiments, when the reference charging strategy is the second reference strategy, the target battery is charged at a constant charging current.

[0061] In some embodiments, when the reference charging strategy is the third reference strategy, the target battery is charged at a constant charging voltage.

[0062] The embodiments of the present application can safely, reasonably and flexibly charge the target battery based on the charging strategy, can be applied to batteries with different charging parameters, charging environments, types and states, and significantly improve the flexibility and safety of battery charging.

[0063] Please refer to Figure 3 , Figure 3 An illustrative sub-flow diagram of step S43 in the intelligent charging method provided by some embodiments of the present application is shown.

[0064] As Figure 3 shown, in some embodiments, based on the reference temperature and the reference health degree, the charging cut-off voltage and the charging maintenance voltage of the target battery are obtained, specifically including but not limited to the following steps S431-S433:

[0065] S431: Obtain a voltage reference table.

[0066] S432: Determine the charging voltage corresponding to the reference temperature and the reference health degree in the voltage reference table as the charging maintenance voltage.

[0067] S433: Multiply the charging maintenance voltage by a third preset value to obtain the charging cut-off voltage.

[0068] In the present embodiment, the voltage reference table is used to represent the correspondence between the temperature, health degree and charging voltage of the target battery.

[0069] The voltage reference table is stored in the local storage of the charger, a server or a cloud, or any suitable storage medium. The embodiments of the present application directly obtain the voltage reference table corresponding to the target battery from the local storage, a server or a cloud, or any suitable storage medium according to the battery type of the target battery. Then, the charging voltage corresponding to the reference temperature and the reference health degree in the voltage reference table is determined as the charging maintenance voltage. The charging maintenance voltage is multiplied by a third preset value to obtain the charging cut-off voltage. In some embodiments, the third preset value is 0.95, so that the charging maintenance voltage is greater than the charging cut-off voltage.

[0070] In some embodiments, the voltage reference table is shown in Table 1 as follows:

[0071] Table 1:

[0072]

[0073] According to Table 1, when the reference temperature is 35℃ and the reference health degree is 100%, the charging voltage corresponding to the reference temperature 35℃ and the reference health degree 100% in Table 1 is 14.5V, and it is determined that the charging voltage 14.5V is the charging maintenance voltage of the target battery. The charging cut-off voltage is obtained by multiplying the charging maintenance voltage 14.5V by the third preset value 0.95, that is, 13.55V. .

[0074] It is easy to understand that Table 1 is only a schematic example of the correspondence between the temperature, health degree and charging voltage of the target battery. In actual application, an engineer can divide a more detailed health degree and temperature or health degree interval and temperature interval according to experimental data and experience data, fill in the charging voltage corresponding to the health degree and temperature or health degree interval and temperature interval table, and thus obtain a voltage reference table. The present embodiment does not make any limitation on this.

[0075] In some embodiments, based on the relative reference voltage, the charging cut-off voltage and the charging maintenance voltage, the reference charging strategy of the target battery is determined, specifically including but not limited to the following steps S441-S442:

[0076] S441: In response to the relative reference voltage being less than the first voltage threshold, the normal state is determined as the initial state of charge of the target battery.

[0077] S442: In response to the initial state of charge of the target battery being the normal state, the first charging strategy corresponding to the normal state is determined as the reference charging strategy of the target battery.

[0078] In the present embodiment, the initial state of charge is the state of charge of the target battery before starting charging.

[0079] For example, the first voltage threshold is 12.7V and the second voltage threshold is 13.2V. Before charging the target battery, the relative reference voltage is compared with the first voltage threshold 12.7V and the second voltage threshold 13.2V. When the relative reference voltage is less than the first voltage threshold 12.7V, it indicates that the state of charge of the target battery before starting charging is at a normal level, that is, the initial state of charge is in the normal state, and the normal state is determined as the initial state of charge of the target battery. The first charging strategy corresponding to the normal state is determined as the reference charging strategy of the target battery.

[0080] In some embodiments, based on the relative reference voltage, the charging cut-off voltage and the charging maintenance voltage, the reference charging strategy of the target battery is determined, specifically including but not limited to the following steps S443-S444:

[0081] S443: In response to the relative reference voltage being greater than or equal to the first voltage threshold and less than the second voltage threshold, determining that the high state is the initial state of charge of the target battery.

[0082] S444: In response to the initial state of charge of the target battery being the high state, determining that the second charging strategy corresponding to the high state is the reference charging strategy of the target battery.

[0083] For example, when the relative reference voltage is greater than or equal to the first voltage threshold 12.7V and less than the second voltage threshold 13.2V, it indicates that the amount of electricity of the target battery before starting charging is at a high level, i.e., the initial state of charge is in the high state, and it is determined that the high state is the initial state of charge of the target battery. The second charging strategy corresponding to the high state is determined as the reference charging strategy of the target battery.

[0084] In some embodiments, the reference charging strategy of the target battery is determined based on the relative reference voltage, the charging cutoff voltage, and the charging maintenance voltage, specifically including but not limited to the following steps S445-S446:

[0085] S445: In response to the relative reference voltage being greater than or equal to the second voltage threshold, determining that the full state is the initial state of charge of the target battery.

[0086] S446: In response to the initial state of charge of the target battery being the full state, determining that the third charging strategy corresponding to the full state is the reference charging strategy of the target battery.

[0087] For example, when the relative reference voltage is greater than or equal to the second voltage threshold 13.2V, it indicates that the amount of electricity of the target battery before starting charging is at a full level, i.e., the initial state of charge is in the full state, and it is determined that the full state is the initial state of charge of the target battery. The third charging strategy corresponding to the full state is determined as the reference charging strategy of the target battery.

[0088] In some embodiments, the reference charging strategy of the target battery is determined based on the relative reference voltage, the charging cutoff voltage, and the charging maintenance voltage, specifically including but not limited to the following steps S44A-S44B:

[0089] S44A: In response to the relative reference voltage being less than the charging cutoff voltage, determining that the normal state is the reference state of charge of the target battery.

[0090] S44B: In response to the reference state of charge of the target battery being the normal state, determining that the first charging strategy corresponding to the normal state is the reference charging strategy of the target battery.

[0091] In this embodiment, the reference state of charge is the actual state of charge of the target battery during the charging process.

[0092] Specifically, the charging cut-off voltage is 13.775 V, and the charging maintenance voltage is 14.5 V. During the charging process of the target battery, the relative reference voltage is compared with the charging cut-off voltage 13.775 V and the charging maintenance voltage 14.5 V. When the relative reference voltage is less than the charging cut-off voltage 13.775 V, it indicates that the power of the target battery during the charging process is at a normal level, that is, the reference power state is in a normal state. The normal state is determined as the reference power state of the target battery, and the first charging strategy corresponding to the normal state is determined as the reference charging strategy of the target battery.

[0093] In some embodiments, the reference charging strategy of the target battery is determined based on the relative reference voltage, the charging cut-off voltage, and the charging maintenance voltage, specifically including but not limited to the following steps S44C-S44D:

[0094] S44C: in response to the relative reference voltage being greater than or equal to the charging cut-off voltage and less than the charging maintenance voltage, determining that the high power state is the reference power state of the target battery.

[0095] S44D: in response to the reference power state of the target battery being the high power state, determining that the second charging strategy corresponding to the high power state is the reference charging strategy of the target battery.

[0096] Specifically, when the relative reference voltage is greater than or equal to the charging cut-off voltage 13.775 V and less than the charging maintenance voltage 14.5 V, it indicates that the power of the target battery during the charging process is at a high power level, that is, the reference power state is in a high power state. The high power state is determined as the reference power state of the target battery, and the second charging strategy corresponding to the high power state is determined as the reference charging strategy of the target battery.

[0097] In some embodiments, the reference charging strategy of the target battery is determined based on the relative reference voltage, the charging cut-off voltage, and the charging maintenance voltage, specifically including but not limited to the following steps S44E-S44F:

[0098] S44E: in response to the relative reference voltage being greater than or equal to the charging maintenance voltage, determining that the full power state is the reference power state of the target battery.

[0099] S44F: in response to the reference power state of the target battery being the full power state, determining that the third charging strategy corresponding to the full power state is the reference charging strategy of the target battery.

[0100] Specifically, when the relative reference voltage is greater than or equal to the charging maintenance voltage 14.5V, it indicates that the power of the target battery in the charging process is at a full power level, that is, the reference power state is at a full power state, the full power state is determined as the reference power state of the target battery, and the third charging strategy corresponding to the full power state is determined as the reference charging strategy of the target battery.

[0101] Referring to Figure 4 , Figure 4 A sub-process schematic diagram of step S45 in the intelligent charging method provided by some embodiments of the present application is schematically shown.

[0102] As Figure 4 shown, in some embodiments, the target battery is charged based on the reference charging strategy, which specifically includes but is not limited to the following steps S451-S457:

[0103] S451: in response to the reference charging strategy being the first charging strategy, calculating the reference internal resistance value of the target battery based on the reference temperature.

[0104] In the embodiments of the present application, the internal resistance calculation formula is: wherein, is the reference internal resistance value of the target battery, is a natural constant, is the reference temperature of the target battery. In the embodiments of the present application, the internal resistance calculation formula is obtained by analyzing and fitting the test data obtained by performing an offline direct current internal resistance test experiment on the battery, and the internal resistance calculation formula is used to represent the formula of the direct current internal resistance of the battery changing with temperature.

[0105] Specifically, when the reference charging strategy is the first charging strategy, the reference temperature of the target battery is substituted into the internal resistance calculation formula (such as the internal resistance calculation formula described above) to calculate the reference internal resistance value of the target battery.

[0106] S452: starting charging the target battery with a preset first charging current.

[0107] The first charging current is a smaller charging current, which prevents the unknown capacity target battery from being damaged by overcurrent charging when starting to charge the target battery.

[0108] S453: obtaining a first candidate voltage and a second candidate voltage of the target battery, wherein the first candidate voltage is the relative reference voltage of the target battery before starting charging, and the second candidate voltage is the relative reference voltage of the target battery when starting charging.

[0109] For example, before charging the target battery, the relative reference voltage of the target battery before starting charging is obtained as the first candidate voltage, and when starting charging the target battery, the relative reference voltage of the target battery at the time of starting charging is obtained as the second candidate voltage.

[0110] S454: Calculate the relative internal resistance value of the target battery based on the first charging current, the first candidate voltage and the second candidate voltage.

[0111] In some embodiments, the relative internal resistance value of the target battery is calculated based on the first charging current, the first candidate voltage and the second candidate voltage, specifically including but not limited to the following steps S4541-S4542:

[0112] S4541: Subtract the second candidate voltage from the first candidate voltage to obtain a first voltage difference.

[0113] S4542: Divide the first voltage difference by the first charging current to obtain the relative internal resistance value.

[0114] In this embodiment, the relative internal resistance value of the target battery is calculated according to the following formula: , wherein, , the first candidate voltage and the second candidate voltage of the target battery respectively, the first charging current, and the first charging current, the first candidate voltage and the second candidate voltage are substituted into the above formula to calculate the relative internal resistance value of the target battery.

[0115] S455: Calculate the reference capacity of the target battery based on the reference internal resistance value and the relative internal resistance value.

[0116] For example, in some embodiments, the relative internal resistance value is multiplied by the internal resistance calibration coefficient to obtain a first calibrated internal resistance, the reference internal resistance value is divided by the first calibrated internal resistance to obtain a first ratio, and the first ratio is multiplied by the rated capacity of the target battery to obtain the reference capacity of the target battery.

[0117] In some embodiments, the reference capacity of the target battery is calculated based on the reference internal resistance value and the relative internal resistance value, specifically including but not limited to the following steps S4551-S4552:

[0118] S4551: Obtain the rated capacity of the target battery.

[0119] S4552: Divide the product of the rated capacity and the reference internal resistance value by the relative internal resistance value to obtain the reference capacity.

[0120] In this step, the reference capacity of the target battery is calculated according to the following formula: , the reference capacity of the target battery, a rated capacity of the target battery, , a reference capacity of the target battery, wherein the rated capacity, the reference resistance value and the relative resistance value of the target battery are substituted into the above formula.

[0121] S456: dividing the reference capacity by the charging hour rate to obtain a reference charging current of the target battery.

[0122] In this step, the charging hour rate is the time preset according to hours for the target battery to be fully charged, for example, the charging hour rate is 1 hour, that is, the charging time of 1 hour is preset to fully charge the target battery.

[0123] For example, the reference capacity and the charging hour rate are substituted into the following formula: to obtain the reference charging current. In the above formula, is the reference charging current, is the reference capacity, is the charging hour rate.

[0124] S457: charging the target battery based on the reference charging current.

[0125] For example, after determining the reference charging current, the target battery is formally charged at the reference charging current.

[0126] In some embodiments, the target battery is charged based on the reference charging current, specifically including but not limited to the following steps S4571-S4573:

[0127] S4571: detecting a voltage increase value of the target battery every interval of a first preset time length.

[0128] In this embodiment, the voltage increase value is the change value of the actual voltage of the target battery during the charging process.

[0129] For example, after formally charging the target battery, every interval of a first preset time length, the embodiment of the application obtains a first sampling voltage value at the start time of the first preset time length and a second sampling voltage value at the end time of the first preset time length from the voltage sampling circuit, and obtains the voltage increase value of the target battery by subtracting the first sampling voltage value from the second sampling voltage value.

[0130] For example, the first preset time length is 300 seconds, when the target battery is formally charged, the timer starts to count the first preset time length, at this time the first sampling voltage value is 13.4V, when the timer counts the first preset time length, at this time the second sampling voltage value is 13.48V. For example, the second sampling voltage value 13.48V is subtracted by the first sampling voltage value 13.4V, and the voltage lifting value of the target battery is 0.08V. .

[0131] S4572: in response to the relative reference voltage of the target battery being less than the third voltage threshold value and the voltage lifting value being greater than the fourth voltage threshold value, or the relative reference voltage of the target battery being greater than or equal to the third voltage threshold value and the voltage lifting value being greater than the fifth voltage threshold value, multiplying the reference charging current by the first coefficient to obtain a step-down current.

[0132] S4573: charging the target battery with the step-down current.

[0133] In the embodiment, the third voltage threshold value is 13.5V, the fourth voltage threshold value is 0.07V, the fifth voltage threshold value is 0.12V, the sixth voltage threshold value is 0.03V, and the seventh voltage threshold value is 0.08V.

[0134] The relative reference voltage of the target battery is compared with the third voltage threshold value 13.5V, and the voltage lifting value is compared with the fourth voltage threshold value 0.07V, the fifth voltage threshold value 0.12V, the sixth voltage threshold value 0.03V and the seventh voltage threshold value 0.08V. If the relative reference voltage of the target battery is less than the third voltage threshold value 13.5V and the voltage lifting value is greater than the fourth voltage threshold value 0.07V, or the relative reference voltage of the target battery is greater than or equal to the third voltage threshold value 13.5V and the voltage lifting value is greater than the fifth voltage threshold value 0.12V, it indicates that the voltage of the target battery is lifted too fast, and the current charging current of the target battery needs to be reduced. In some embodiments of the application, the first coefficient is set to 0.95, the reference charging current is multiplied by the first coefficient 0.95 to obtain a step-down current, and the target battery is charged with the step-down current.

[0135] In some embodiments, the target battery is charged based on the reference charging current, specifically including but not limited to the following steps S4574-S4575:

[0136] S4574: in response to the relative reference voltage of the target battery being less than the third voltage threshold value and the voltage lifting value being less than the sixth voltage threshold value, or the relative reference voltage of the target battery being greater than or equal to the third voltage threshold value and the voltage lifting value being less than the seventh voltage threshold value, multiplying the reference charging current by the second coefficient to obtain a step-up current, the reference charging current being greater than the step-down current and less than the step-up current;

[0137] S4575: Charges the target battery with boost current.

[0138] For example, when the relative reference voltage of the target battery is less than the third voltage threshold of 13.5V and the voltage boost is less than the sixth voltage threshold of 0.03V, or when the relative reference voltage of the target battery is greater than or equal to the third voltage threshold of 13.5V and the voltage boost is less than the seventh voltage threshold of 0.08V, it indicates that the voltage boost of the target battery is too slow and the current charging current of the target battery needs to be increased. In this embodiment, the second coefficient is set to 1.05. The reference charging current is multiplied by the second coefficient 1.05 to obtain the boost current, and the target battery is charged with the boost current.

[0139] In some embodiments, the target battery is charged based on a reference charging current, specifically including but not limited to the following steps S4576-S4577:

[0140] S4576: In response to the target battery's relative reference voltage being less than the third voltage threshold and the voltage boost being greater than or equal to the sixth voltage threshold and less than or equal to the fourth voltage threshold, or the target battery's relative reference voltage being greater than or equal to the third voltage threshold and the voltage boost being greater than or equal to the seventh voltage threshold and less than or equal to the fifth voltage threshold, maintain the target battery's reference charging current unchanged.

[0141] For example, when the relative reference voltage of the target battery is less than the third voltage threshold of 13.5V and the voltage boost is greater than or equal to the sixth voltage threshold of 0.03V and less than or equal to the fourth voltage threshold of 0.07V, or when the relative reference voltage of the target battery is greater than or equal to the third voltage threshold of 13.5V and the voltage boost is greater than or equal to the seventh voltage threshold of 0.08V and less than or equal to the fifth voltage threshold of 0.12V, it indicates that the voltage boost of the target battery is appropriate, and there is no need to change the current charging current of the target battery. The reference charging current of the target battery is kept unchanged, and the target battery is continuously charged with the reference charging current.

[0142] S4577: In response to a preset number of consecutive detections that the voltage rise value is greater than or equal to the sixth voltage threshold and less than or equal to the fourth voltage threshold, or the voltage rise value is greater than or equal to the seventh voltage threshold and less than or equal to the fifth voltage threshold, the target battery is charged with the current reference charging current.

[0143] In this embodiment, the reference charging current is the charging current when the voltage increase value of the target battery detected for a preset number of times continuously meets a preset condition. The target battery is charged at the reference charging current, and the voltage of the target battery can be stably and reasonably increased (i.e., the voltage increase value is stable and reasonable). The preset condition means that the voltage increase value is greater than or equal to the sixth voltage threshold and less than or equal to the fourth voltage threshold, or the voltage increase value is greater than or equal to the seventh voltage threshold and less than or equal to the fifth voltage threshold.

[0144] In this embodiment, the preset number of times is 2. When the voltage increase value is greater than or equal to the sixth voltage threshold 0.03 V and less than or equal to the fourth voltage threshold 0.07 V, or the voltage increase value is greater than or equal to the seventh voltage threshold 0.08 V and less than or equal to the fifth voltage threshold 0.12 V, it is indicated that the current reference charging current of the target battery can appropriately increase the voltage of the target battery. The target battery is continuously charged at the current reference charging current in this embodiment. It can be understood that the preset number of times can be any suitable number, and the embodiment of the present application does not make any limitation on this.

[0145] In some embodiments, the target battery is charged based on the reference charging strategy, and specifically further includes but is not limited to the following steps S458-S459:

[0146] S458: In response to the reference charging strategy being the second charging strategy, the target battery is charged at a preset second charging current.

[0147] S549: In response to the reference charging strategy being the third charging strategy, the target battery is charged at a preset first charging voltage.

[0148] For example, when the reference charging strategy is the second reference strategy, the target battery is charged in a constant current charging mode, i.e., the target battery is charged in a constant current charging mode at a preset second charging current.

[0149] For example, when the reference charging strategy is the third reference strategy, the target battery is charged in a constant voltage charging mode, i.e., the target battery is charged in a constant voltage charging mode at a preset first charging voltage.

[0150] In some embodiments, the target battery is charged based on the reference charging strategy, and specifically further includes but is not limited to the following steps S45A-S45E:

[0151] S45A: In response to the relative reference voltage being less than the eighth voltage threshold, a new candidate health degree of the target battery is obtained.

[0152] For example, the eighth voltage threshold is set to 13.4V. The relative reference voltage of the target battery is compared with the eighth voltage threshold of 13.4V. When the relative reference voltage is less than the eighth voltage threshold of 13.4V, a new candidate health of the target battery is calculated based on the reference voltage, reference current, reference temperature and reference health.

[0153] In some embodiments, in response to a relative reference voltage being less than an eighth voltage threshold, a new candidate health level for the target battery is obtained, specifically including but not limited to the following steps S45A1-S45A5:

[0154] S45A1: When the relative reference voltage is less than the eighth voltage threshold, adjust the charging current of the target battery so that the voltage boost value meets the expected conditions.

[0155] In this embodiment, the voltage boost value meeting the expected condition means that the voltage boost value is greater than or equal to the ninth voltage threshold and less than or equal to the tenth voltage threshold, where the ninth voltage threshold is 0.038V and the tenth voltage threshold is 0.042V. When the relative reference voltage is less than the eighth voltage threshold of 13.4V, the charging current of the target battery is adjusted in the specific manner described in steps S4571-S4577 above, so that the voltage boost value meets the expected condition. The specific adjustment process will not be described in detail. The adjustment coefficients (i.e., the first coefficient and the second coefficient) in this embodiment are different from the adjustment coefficients in steps S4571-S4577 above. In this embodiment, the first coefficient and the second coefficient are 0.99 and 1.01, respectively. When it is necessary to reduce the current charging current of the target battery, the current charging current is multiplied by the first coefficient 0.99 to obtain the step-down current. When it is necessary to increase the current charging current of the target battery, the current charging current is multiplied by the first coefficient 1.01 to obtain the step-up current.

[0156] Understandably, embodiments of the present invention control the voltage boost value within a certain range. Within this voltage range, the target battery's temperature and charging rate (i.e., charging current) exhibit a essentially linear relationship, facilitating the subsequent determination of the target battery's charging current based on its temperature. Please refer to [link / reference]. Figure 5 , Figure 5 The diagram illustrates the relationship between the voltage boost of the target battery and temperature and charging rate. Figure 5 (a) and a schematic diagram of the relationship between the charging rate (i.e., charging current) and temperature of the target battery. Figure 5 (b) Among them, Figure 5 The curve diagram shown in Figure b is based on Figure 5 The voltage boost value of the target battery in the schematic diagram of curve a is located at... The relationship curve between charging rate and temperature is obtained by fitting the charging rate and temperature data within a certain range.

[0157] S45A2: determining the real charging current of the target battery based on the standard temperature of the target battery after the voltage boost value meets the expected condition.

[0158] wherein the standard temperature is the temperature of the target battery after the voltage boost value meets the expected condition.

[0159] In some embodiments, the standard temperature is substituted into the temperature current formula to calculate the real charging current of the target battery. It can be understood that the temperature current formula is a formula representing the corresponding relationship between the charging current of the target battery and the temperature.

[0160] For example, please refer to the schematic diagram of the relationship curve between the charging rate (i.e. charging current) of the target battery and the temperature shown in FIG. 5A2-1. Figure 5 , Figure 5 After fitting the relationship curve, the temperature current formula is obtained, and the standard temperature is substituted into the temperature current formula to calculate the real charging current of the target battery.

[0161] Exemplarily, in some embodiments, the real charging current of the target battery is determined based on the standard temperature of the target battery, specifically including but not limited to the following steps S45A21-S45A22:

[0162] S45A21: obtaining a current reference table.

[0163] S45A22: determining the charging current corresponding to the standard temperature in the current reference table as the real charging current.

[0164] wherein the current reference table is used to represent the corresponding relationship between the temperature of the target battery and the charging current (i.e. charging rate). For example, in some embodiments, the current reference table is shown in Table 2 as follows:

[0165] Table 2:

[0166]

[0167] In some embodiments, the engineering personnel can design the current reference table in advance according to experimental data and empirical data, etc., and store the current reference table in any suitable storage medium such as the local storage of the charger, the server or the cloud, etc. The current reference table is obtained from the local storage, the server or the cloud, etc.

[0168] Exemplarily, the charging current corresponding to the standard temperature is found out in the current reference table, and the charging current corresponding to the standard temperature is determined as the real charging current. For example, the standard temperature is 25℃, and the charging current corresponding to the standard temperature 25℃ is 0.167C, then the charging current 0.167C is determined as the real charging current of the target battery.

[0169] It is easy to understand that Table 2 is only a schematic example showing the correspondence between the temperature of the target battery and the charging current (i.e. the charging rate), and in actual applications, an engineer can divide more detailed temperatures or temperature intervals according to experimental data and empirical data, and fill in the charging current / charging rate corresponding to the temperature or temperature interval in the table to obtain the current reference table, and the embodiments of the present application do not make any limitation on this.

[0170] S45A3: Based on the real charging current and the standard charging current, the real capacity of the target battery is calculated.

[0171] In the embodiments of the present application, the standard charging current is the current of the target battery after the voltage increase value meets the expected condition.

[0172] For example, the standard charging current is divided by the real charging current to obtain the real capacity of the target battery.

[0173] S45A4: Based on the real capacity and the reference internal resistance value, the reference internal resistance value of the target battery is calculated.

[0174] For example, the reference internal resistance value is multiplied by the resistance coefficient to obtain the reference internal resistance value, and the reference internal resistance value is divided by the real capacity of the target battery to obtain the reference internal resistance value of the target battery.

[0175] In some embodiments, based on the real capacity and the reference internal resistance value, the reference internal resistance value of the target battery is calculated, which specifically includes but is not limited to the following steps S45A41-S45A42:

[0176] S45A41: The rated capacity of the target battery is obtained.

[0177] S45A42: The product of the rated capacity and the reference internal resistance value is divided by the real capacity to obtain the reference internal resistance value.

[0178] In some embodiments, the rated capacity (for example, 100 Ah) of the target battery is obtained, the rated capacity is multiplied by the reference internal resistance value to obtain a first product. The first product is divided by the real capacity of the target battery to obtain the reference internal resistance value of the target battery.

[0179] In the embodiments, the following formula is used: , is the real capacity of the target battery, is the rated capacity of the target battery, is the reference internal resistance value of the target battery, is the product of the rated capacity and the reference internal resistance value, is the reference internal resistance value of the target battery, and the rated capacity, the real capacity and the reference internal resistance value of the target battery are substituted into the above formula to calculate the reference internal resistance value of the target battery.

[0180] S45A5: Calculate the candidate health degree based on the reference internal resistance value and the relative internal resistance value.

[0181] In some embodiments, the candidate health degree is calculated based on the reference internal resistance value and the relative internal resistance value, specifically including but not limited to the following steps S45A51-S45A52:

[0182] S45A51: Multiply the first calculation value by the first ratio to obtain a first value.

[0183] S45A52: Subtract the first value from the standard health degree to obtain the candidate health degree.

[0184] In this embodiment, the first calculation value is the difference between the quotient value obtained by dividing the relative internal resistance value by the reference internal resistance value and the sixth preset value, and the sixth preset value is 1. The first ratio is 33.3%. Divide the relative internal resistance value by the reference internal resistance value to obtain the first quotient value. Subtract the sixth preset value 1 from the first quotient value to obtain the first calculation value. Multiply the first calculation value by the first ratio to obtain the first value. Subtract the first value from the standard health degree to obtain the candidate health degree.

[0185] In this step, the following formula is used: , is the new candidate health degree of the target battery, is the standard health degree 100%, is the reference internal resistance value of the target battery, is the relative internal resistance value of the target battery, is the sixth preset value 1, is the first ratio 33.3%, and the reference internal resistance value and the relative internal resistance value of the target battery are substituted into the above formula to calculate the candidate health degree of the target battery.

[0186] In the embodiments of the present application, the corresponding relationship between the internal resistance change and the health degree decay of the target battery is obtained according to the reference "Research on Life Prediction and Equalization Control Technology of Station Lead-acid Battery". As described in the reference, when the battery capacity decays from 100% to 80%, the battery internal resistance increases from 0.1 ohm to 0.2 ohm, which is equivalent to an increase of 1 times the battery internal resistance, and the battery health degree decays to 66%. Therefore, the battery health degree calculation formula is: .

[0187] S45B: In response to the candidate health degree being less than the reference health degree, updating the reference health degree of the target battery to the first health degree.

[0188] S45C: In response to the candidate health degree being greater than or equal to the reference health degree, maintaining the reference health degree of the target battery unchanged. ​​​​

[0189] In the embodiment of the present application, the first health degree is the difference between the reference health degree and the fifth preset value, and the fifth preset value is 0.1%. When the candidate health degree is less than the reference health degree, the reference health degree of the target battery is updated to the first health degree. When the candidate health degree is greater than or equal to the reference health degree, the reference health degree of the target battery is maintained unchanged.

[0190] For example, the reference health degree is 100.0%, and the candidate health degree is 99.0%. Obviously, the candidate health degree 99.0% is less than the reference health degree 100.0%, and the first health degree is , and the reference health degree of the target battery is updated to the first health degree 99.9%. Assuming that 99.0% is the accurate true health degree, after the target battery is charged for the tenth time, the finally updated reference health degree is the same as the true health degree (i.e. ).

[0191] S45D: determining the candidate charging current of the target battery.

[0192] In the embodiment, the candidate charging current is one of the reference charging current, the second charging current and the third charging current. The third charging current is the maximum charging current in the charging process of the target battery at the preset first charging voltage. The candidate charging current represents the most stable charging current in the charging process of the target battery.

[0193] In the embodiment of the present application, when the initial state of charge of the target battery is the normal state, the candidate charging current is the final steady-state charging current after current adjustment (i.e. the reference charging current). When the initial state of charge of the target battery is the high state of charge or the full state of charge, the candidate charging current is the maximum of the second charging current and the third charging current, that is, when the second charging current is greater than the third charging current, the candidate charging current is the second charging current, and when the second charging current is less than the third charging current, the candidate charging current is the third charging current.

[0194] S45E: stopping charging the target battery in response to that the reference current is less than or equal to the charging cutoff current, or the state of charge value of the target battery reaches the preset charge value.

[0195] In the embodiment, the charging cutoff current is the product of the candidate charging current and the fourth preset value, and the fourth preset value is 0.1. The state of charge value of the target battery is obtained, the reference current is compared with the charging cutoff current, and the state of charge value of the target battery is compared with the preset charge value. When the reference current is less than or equal to the charging cutoff current, or the state of charge value of the target battery reaches the preset charge value, it indicates that the target battery is fully charged, and the charging operation is closed to stop charging the target battery.

[0196] In summary, the intelligent charging method provided by the embodiment of the present application is applied to a charger, the charger is electrically connected with a target battery, the relative reference voltage is calculated according to the reference voltage of the target battery, the charging cutoff voltage and the charging maintenance voltage are obtained according to the reference temperature and the reference health degree of the target battery, and then a reasonable and safe charging strategy is flexibly determined according to the relative reference voltage, the charging cutoff voltage and the charging maintenance voltage, so that the target battery can be safely, reasonably and flexibly charged based on the charging strategy, the battery with different charging parameters, charging environments, types and states can be applied, and the flexibility and safety of battery charging are significantly improved.

[0197] It should be noted that the above embodiments are used to illustrate the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it accordingly, and cannot be used to limit the protection scope of the present application. Those skilled in the art can understand that all or part of the processes of the above embodiments are implemented, and the technical solutions described in the embodiments of the present application are modified or some technical features are replaced. It can be understood that these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and should be regarded as equivalent changes and modifications based on the embodiments of the present application, and should belong to the scope covered by the claims of the present application.

Claims

1. A smart charging method applied to a charger, characterized in that, The charger is electrically connected with the target battery, and the method comprises: obtaining a reference voltage, a reference current, a reference temperature and a reference health degree of the target battery, wherein the reference voltage, the reference current and the reference temperature are actual voltage, actual current and actual temperature of the target battery in a charging process respectively; calculating a relative reference voltage of the target battery based on the reference voltage; obtaining a charging cut-off voltage and a charging maintenance voltage of the target battery based on the reference temperature and the reference health degree; determining a reference charging strategy of the target battery based on the relative reference voltage, the charging cut-off voltage and the charging maintenance voltage, wherein the reference charging strategy is used to represent a manner of adjusting current of the target battery in the charging process; charging the target battery based on the reference charging strategy.

2. The intelligent charging method of claim 1, wherein, The method comprises: According to the rounding rule, the quotient obtained by dividing the reference voltage by a first preset value is rounded to obtain a reference quantity; the product of the reference voltage and a second preset value is divided by the reference quantity to obtain the relative reference voltage.

3. The intelligent charging method of claim 1, wherein, The method comprises: obtaining a voltage reference table, wherein the voltage reference table is used to represent the corresponding relationship between temperature, health degree and charging voltage of the target battery; determining the charging voltage corresponding to the reference temperature and the reference health degree in the voltage reference table as the charging maintenance voltage; multiplying the charging maintenance voltage by a third preset value to obtain the charging cut-off voltage.

4. The intelligent charging method of claim 1, wherein, The method comprises: in response to the relative reference voltage being less than a first voltage threshold, determining a normal state as an initial power state of the target battery, wherein the initial power state is a power state of the target battery before starting charging; in response to the initial power state of the target battery being the normal state, determining a first charging strategy corresponding to the normal state as the reference charging strategy of the target battery; or, in response to the relative reference voltage being greater than or equal to the first voltage threshold and less than a second voltage threshold, determining a high state as the initial power state of the target battery; in response to the initial power state of the target battery being the high state, determining a second charging strategy corresponding to the high state as the reference charging strategy of the target battery; or, in response to the relative reference voltage being greater than or equal to the second voltage threshold, determining a full state as the initial power state of the target battery; in response to the initial power state of the target battery being the full state, determining a third charging strategy corresponding to the full state as the reference charging strategy of the target battery.

5. The intelligent charging method of claim 1, wherein, The method comprises: determining, in response to the relative reference voltage being less than the charging cutoff voltage, a normal state as a reference state of charge of the target battery, the reference state of charge being an actual state of charge of the target battery during a charging process; determining, in response to the reference state of charge of the target battery being the normal state, a first charging strategy corresponding to the normal state as a reference charging strategy of the target battery; or determining, in response to the relative reference voltage being greater than or equal to the charging cutoff voltage and less than the charging maintenance voltage, a high state as the reference state of charge of the target battery; determining, in response to the reference state of charge of the target battery being the high state, a second charging strategy corresponding to the high state as the reference charging strategy of the target battery; or determining, in response to the relative reference voltage being greater than or equal to the charging maintenance voltage, a full state as the reference state of charge of the target battery; determining, in response to the reference state of charge of the target battery being the full state, a third charging strategy corresponding to the full state as the reference charging strategy of the target battery.

6. The intelligent charging method according to claim 4 or 5, characterized in that, the charging of the target battery based on the reference charging strategy comprises: calculating a reference internal resistance value of the target battery based on the reference temperature in response to the reference charging strategy being the first charging strategy; starting the charging of the target battery at a preset first charging current; obtaining a first candidate voltage and a second candidate voltage of the target battery, wherein the first candidate voltage is a relative reference voltage of the target battery before the charging is started, and the second candidate voltage is a relative reference voltage of the target battery when the charging is started; calculating a relative internal resistance value of the target battery based on the first charging current, the first candidate voltage and the second candidate voltage; calculating a reference capacity of the target battery based on the reference internal resistance value and the relative internal resistance value; dividing the reference capacity by a charging hour rate to obtain a reference charging current of the target battery, the charging hour rate being a time for the target battery to be fully charged according to hours; charging the target battery based on the reference charging current.

7. The intelligent charging method of claim 6, wherein, the calculating of the relative internal resistance value of the target battery based on the first charging current, the first candidate voltage and the second candidate voltage comprises: subtracting the second candidate voltage from the first candidate voltage to obtain a first voltage difference value; dividing the first voltage difference value by the first charging current to obtain the relative internal resistance value.

8. The intelligent charging method of claim 6, wherein, the calculating of the reference capacity of the target battery based on the reference internal resistance value and the relative internal resistance value comprises: obtaining a rated capacity of the target battery; dividing a product of the rated capacity and the reference internal resistance value by the relative internal resistance value to obtain the reference capacity.

9. The intelligent charging method of claim 6, wherein, the charging of the target battery based on the reference charging current comprises: detecting a voltage increase value of the target battery every first preset time length, the voltage increase value being a change value of an actual voltage of the target battery during the charging process; multiplying the reference charging current by a first coefficient to obtain a step-down current, in response to the relative reference voltage of the target battery being less than a third voltage threshold and the voltage boost value being greater than a fourth voltage threshold, or the relative reference voltage of the target battery being greater than or equal to the third voltage threshold and the voltage boost value being greater than a fifth voltage threshold; charging the target battery with the step-down current; or multiplying the reference charging current by a second coefficient to obtain a step-up current, in response to the relative reference voltage of the target battery being less than the third voltage threshold and the voltage boost value being less than a sixth voltage threshold, or the relative reference voltage of the target battery being greater than or equal to the third voltage threshold and the voltage boost value being less than a seventh voltage threshold, the reference charging current being greater than the step-down current and less than the step-up current; charging the target battery with the step-up current; or maintaining the reference charging current of the target battery unchanged, in response to the relative reference voltage of the target battery being less than the third voltage threshold and the voltage boost value being greater than or equal to the sixth voltage threshold and less than or equal to the fourth voltage threshold, or the relative reference voltage of the target battery being greater than or equal to the third voltage threshold and the voltage boost value being greater than or equal to the seventh voltage threshold and less than or equal to the fifth voltage threshold; charging the target battery with a current reference charging current, in response to detecting the voltage boost value being greater than or equal to the sixth voltage threshold and less than or equal to the fourth voltage threshold, or the voltage boost value being greater than or equal to the seventh voltage threshold and less than or equal to the fifth voltage threshold, for a preset number of times in succession, the current reference charging current being the charging current when the voltage boost value of the target battery meets the preset condition for the preset number of times in succession.

10. The intelligent charging method of claim 9, wherein, The charging the target battery based on the reference charging strategy further includes: charging the target battery with a preset second charging current, in response to the reference charging strategy being a second charging strategy; charging the target battery with a preset first charging voltage, in response to the reference charging strategy being a third charging strategy.

11. The intelligent charging method of claim 10, wherein, The charging the target battery based on the reference charging strategy further includes: obtaining a new candidate state of health of the target battery, in response to the relative reference voltage being less than an eighth voltage threshold; updating the reference state of health of the target battery to be a first state of health, in response to the candidate state of health being less than the reference state of health, the first state of health being a difference between the reference state of health and a fifth preset value; maintaining the reference state of health of the target battery unchanged, in response to the candidate state of health being greater than or equal to the reference state of health; determining a candidate charging current of the target battery, the candidate charging current being one of the reference charging current, a second charging current and a third charging current, the third charging current being a maximum charging current in a process of charging the target battery with a preset first charging voltage. In response to the reference current being less than or equal to a charging cutoff current, or a state of charge value of the target battery reaching a preset charge value, stopping charging the target battery, the charging cutoff current being a product of the candidate charging current and a fourth preset value.

12. The intelligent charging method of claim 11, wherein, The obtaining the new candidate health degree of the target battery in response to the relative reference voltage being less than an eighth voltage threshold value comprises: adjusting the charging current of the target battery when the relative reference voltage is less than the eighth voltage threshold value, so that the voltage increase value meets an expected condition; determining a real charging current of the target battery based on a standard temperature of the target battery after the voltage increase value meets the expected condition, the standard temperature being a temperature of the target battery after the voltage increase value meets the expected condition; calculating a real capacity of the target battery based on the real charging current and a standard charging current, the standard charging current being a current of the target battery after the voltage increase value meets the expected condition; calculating a reference internal resistance value of the target battery based on the real capacity and the reference internal resistance value; calculating the candidate health degree based on the reference internal resistance value and a relative internal resistance value.

13. The intelligent charging method of claim 12, wherein, The determining the real charging current of the target battery based on the standard temperature of the target battery comprises: obtaining a current reference table, wherein the current reference table is used to represent a corresponding relationship between a temperature and a charging current of the target battery; determining the charging current corresponding to the standard temperature in the current reference table as the real charging current.

14. The intelligent charging method of claim 12, wherein, The calculating the candidate health degree based on the reference internal resistance value and the relative internal resistance value comprises: multiplying a first calculation value and a first ratio value to obtain a first value, the first calculation value being a difference value between a quotient value obtained by dividing the relative internal resistance value by the reference internal resistance value and a sixth preset value; subtracting the first value from a standard health degree to obtain the candidate health degree.

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