Battery management method, device and system and storage medium

Abstract

The invention discloses a battery management method, device and system and a storage medium. The method is applied to a battery management system, the battery management system comprises a lithium battery and a voltage sampling circuit, and the method comprises the following steps: in response to the triggering of a battery management event, collecting the current battery voltage of the lithium battery and the current external power supply voltage through the voltage sampling circuit, and obtaining the current temperature of the lithium battery; when it is determined that the charging condition of the lithium battery is met according to the current battery voltage and the current external power supply voltage, target charging current and target heating current are determined according to the charging characteristic data of the lithium battery; and charging the lithium battery based on the target charging current, and heating the lithium battery based on the target heating current. According to the scheme, the lithium battery can be charged based on the target charging current according to the battery temperature in real time on the premise that the lithium battery does not generate lithium precipitation while external electric heating is utilized when it is determined that the external has a sufficient charging condition.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a battery management method, device, system and storage medium. Background Art

[0002] Lithium-ion batteries offer higher energy density and cycle life than traditional lead-acid batteries. Consequently, they are widely used in industries such as electrical appliances, automobiles, and energy storage. However, due to their chemical properties, lithium-ion batteries exhibit poor performance at low temperatures. As temperature decreases, the kinetic properties of the battery's graphite negative electrode deteriorate, significantly increasing the electrochemical polarization of the negative electrode during charging. The precipitated metallic lithium easily forms lithium dendrites, which can shorten the battery's lifespan and even penetrate the separator, causing a short circuit between the positive and negative electrodes. The discharge capacity of lithium batteries is also significantly reduced at low temperatures, significantly limiting their application in low-temperature environments. Currently, a common solution on the market is to heat the lithium battery externally.

[0003] In distributed photovoltaic systems, independent off-grid systems, such as solar monitoring systems and off-grid energy storage systems, lack external power sources other than photovoltaics. Therefore, additional external power cannot be used to heat the batteries, and the battery's own power cannot be wasted on heating. For this scenario, an efficient battery heating control device is required that can fully utilize both photovoltaic and battery power. Because externally controlled heating solutions are complex to wire and hinder battery pack assembly and waterproofing, typical outdoor photovoltaic controllers and home energy storage inverters do not include heating controls.

[0004] Figure 1 This is a schematic diagram of a principle of controlling battery heating by an external power supply provided in the related art, such as Figure 1 As shown, the temperature sensor and heating module inside the battery pack are independently connected to the outside of the battery pack, and the heating is controlled independently by an external controller. When the temperature sensor detects that the battery temperature falls below a certain threshold, the external controller stops charging the battery and starts heating. When the temperature reaches a certain threshold, charging resumes. The heating module can only be powered by an external power source, such as photovoltaic power. However, if the photovoltaic power source is out of power and the battery needs to be discharged, it cannot heat the battery. Figure 2 A schematic diagram of the principle of controlling battery heating from within a battery pack provided in the related art, such as Figure 2 As shown, the heating module is connected directly in parallel to the positive and negative terminals of the battery. Because parallel connection makes it impossible to determine whether the voltage is external or battery, when the battery temperature falls below a certain threshold, the charging MOS is disconnected and heating is enabled. This solution uses battery power to power the heating module, and if external power is available, it also provides heating power. When the temperature reaches a certain threshold, the heating is turned off and the charging MOS is restored.

[0005] However, both of the aforementioned solutions set a temperature threshold. When the battery temperature falls below this threshold, charging is stopped and the battery heating function is activated. In a photovoltaic energy storage system, this significantly wastes photovoltaic power. Since the battery temperature rises slowly through heat conduction alone, and the heating module is typically a fixed-wattage resistor, any excess photovoltaic power consumed during the battery heating period is wasted. Furthermore, in solutions where battery heating is controlled by a separate external power source, the heating module is powered by an external photovoltaic source. The heating module and temperature sensor are typically integrated within the battery pack. This requires extending the heating module control wiring and the temperature sensor temperature sensing wiring outside the battery pack to an external controller. This complicates system wiring and affects the waterproof rating of the battery pack and external controller. The battery pack requires a custom external controller to control battery heating, significantly increasing costs. Furthermore, in photovoltaic-powered heating solutions, battery heating is impossible when the photovoltaic source is out of power. In the solution where battery heating is controlled from within the battery pack, the heating module is connected in parallel to the positive and negative terminals of the battery, and the battery heating is controlled by the battery management system. However, it is unable to determine whether the voltage is the external photovoltaic voltage or the battery voltage, resulting in the inability to independently control charging and discharging heating. The battery heating is simply turned on at low temperatures. This can easily cause the battery power to be continuously used for heating under low temperatures, quickly depleting the battery power and making the system's battery life even shorter than when no heating is used. Summary of the Invention

[0006] The present invention provides a battery management method, device, system and storage medium, which can use external electric heating to charge the lithium battery based on the target charging current in real time according to the battery temperature when it is determined that the external charging conditions are sufficient, without causing lithium plating in the lithium battery.

[0007] According to one aspect of the present invention, a battery management method is provided, which is applied to a battery management system. The battery management system includes a lithium battery and a voltage acquisition circuit. The method includes:

[0008] In response to a battery management event being triggered, collecting the current battery voltage and the current external power supply voltage of the lithium battery through the voltage sampling circuit, and obtaining the current temperature of the lithium battery;

[0009] When it is determined that the charging conditions for the lithium battery are met according to the current battery voltage and the current external power supply voltage, a target charging current and a target heating current are determined according to the charging characteristic data of the lithium battery; wherein the target charging current is the charging current that causes the lithium battery to heat up fastest at the current temperature and prevents lithium deposition in the lithium battery;

[0010] The lithium battery is charged based on the target charging current, and the lithium battery is heated based on the target heating current.

[0011] According to another aspect of the present invention, a battery management device is provided, which is applied to a battery management system. The battery management system includes a lithium battery and a voltage acquisition circuit. The device includes:

[0012] a voltage acquisition module, configured to acquire the current battery voltage and the current external power supply voltage of the lithium battery through the voltage sampling circuit in response to a battery management event being triggered, and to obtain the current temperature of the lithium battery;

[0013] a target current determination module, configured to determine a target charging current and a target heating current based on the charging characteristic data of the lithium battery when it is determined that the charging conditions for the lithium battery are met based on the current battery voltage and the current external power supply voltage; wherein the target charging current is the charging current that causes the lithium battery to heat up fastest at the current temperature and prevents lithium deposition in the lithium battery;

[0014] A battery charging management module is configured to charge the lithium battery based on the target charging current and heat the lithium battery based on the target heating current.

[0015] According to another aspect of the present invention, a battery management system is provided, the battery management system including a lithium battery and a voltage acquisition circuit, the battery management system further including:

[0016] at least one processor; and

[0017] a memory communicatively connected to the at least one processor; wherein,

[0018] The memory stores a computer program that can be executed by the at least one processor. The computer program is executed by the at least one processor to enable the at least one processor to perform the battery management method according to any embodiment of the present invention.

[0019] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the battery management method according to any embodiment of the present invention when executed.

[0020] The battery management solution of an embodiment of the present invention is applied to a battery management system, which includes a lithium battery and a voltage acquisition circuit. The method includes: in response to a battery management event being triggered, acquiring the current battery voltage and the current external power supply voltage of the lithium battery through the voltage sampling circuit, and obtaining the current temperature of the lithium battery; when it is determined that the charging conditions for the lithium battery are met based on the current battery voltage and the current external power supply voltage, determining the target charging current and the target heating current based on the charging characteristic data of the lithium battery; wherein the target charging current is the charging current that causes the lithium battery to heat up the fastest at the current temperature and prevents the lithium battery from producing lithium plating; charging the lithium battery based on the target charging current, and heating the lithium battery based on the target heating current. The technical solution provided by the embodiment of the present invention not only solves the technical problems of the lithium battery heating function being turned on only when the lithium battery temperature is lower than a fixed temperature threshold, and the inability to charge the lithium battery during heating, resulting in waste of photovoltaic power, but also, when it is determined that sufficient external charging conditions are available, the lithium battery can be charged in real time based on the target charging current according to the battery temperature while utilizing external electric heating, provided that lithium plating does not occur in the lithium battery. This can minimize waste of external electrical energy, and can also make the internal temperature of the battery rise faster, reach a higher temperature as soon as possible, and resume charging with a larger current.

[0021] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 This is a schematic diagram of a principle of controlling battery heating by an external power supply provided in the related art;

[0024] Figure 2 This is a schematic diagram of the principle of controlling battery heating from within the battery pack provided in the related art;

[0025] Figure 3 This is a flowchart of a battery management method provided according to the first embodiment of the present invention;

[0026] Figure 4 This is a schematic structural diagram of a battery management system provided by an embodiment of the present invention;

[0027] Figure 5a Schematic diagram of battery capacity decay of a lithium battery at different charging temperatures provided by an embodiment of the present invention;

[0028] Figure 5b Schematic diagram of battery capacity attenuation of a lithium battery at different charging rates provided by an embodiment of the present invention;

[0029] Figure 6 is a schematic diagram of internal resistance characteristic data of a lithium battery provided by an embodiment of the present invention;

[0030] Figure 7 is a schematic diagram of discharge characteristic data of a lithium battery provided by an embodiment of the present invention;

[0031] Figure 8 This is a structural diagram of a battery management device provided according to a second embodiment of the present invention;

[0032] Figure 9 1 is a schematic structural diagram of a battery management system for implementing the battery management method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0034] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0035] Example 1

[0036] Figure 3A flowchart of a battery management method is provided for the first embodiment of the present invention. This embodiment is applicable to the case of controlling the charging, discharging and heating of lithium batteries. The method can be executed by a battery management device, which can be implemented in the form of hardware and / or software and can be configured in a battery management system. Figure 3 As shown, the method includes:

[0037] S310 : In response to a battery management event being triggered, the current battery voltage and the current external power supply voltage of the lithium battery are collected through a voltage sampling circuit, and the current temperature of the lithium battery is obtained.

[0038] Figure 4 A schematic diagram of the structure of a battery management system provided by an embodiment of the present invention is shown in FIG. Figure 4 As shown, the battery management system includes a lithium battery (i.e., a cell string), a voltage sampling circuit, a current sampling circuit, a heating module, a temperature sensor, an MCU, a discharge MOS tube, a charging MOS tube and a PWM control circuit. Among them, the voltage sampling circuit includes a voltage acquisition circuit 1, a voltage acquisition circuit 2 and a voltage acquisition circuit 3. The voltage acquisition circuit 1 is used to collect the battery voltage, the voltage acquisition circuit 2 is used to collect the external power supply voltage, the voltage acquisition circuit 3 is used to collect the heating module voltage, and the current acquisition circuit is used to collect the charge and discharge current of the lithium battery.

[0039] In an embodiment of the present invention, upon receiving a battery management instruction input by a user, it is determined that a battery management event has been triggered. In response to the battery management event being triggered, the current battery voltage of the lithium battery is acquired by voltage acquisition circuit 1, the current external power supply voltage is acquired by voltage acquisition circuit 2, and the current temperature of the lithium battery is sensed by a temperature sensor.

[0040] S320. When it is determined that the charging conditions for the lithium battery are met based on the current battery voltage and the current external power supply voltage, a target charging current and a target heating current are determined based on the charging characteristic data of the lithium battery; wherein the target charging current is the charging current that causes the lithium battery to heat up fastest at the current temperature and prevents the lithium battery from producing lithium deposition.

[0041] In an embodiment of the present invention, the current battery voltage and the current external power supply voltage are analyzed, and whether the external charging conditions are sufficient is determined based on the analysis results, that is, whether the charging conditions for the lithium battery are met is determined based on the analysis results. Exemplarily, the voltage difference between the current external power supply voltage and the current battery voltage is calculated, and it is determined whether the voltage difference is greater than a preset voltage threshold. If so, it can be determined that the charging conditions for the lithium battery are met. For example, the preset voltage threshold can be 1V. When it is determined that the charging conditions for the lithium battery are met based on the current battery voltage and the current external power supply voltage, the charging characteristic data of the lithium battery is obtained. Exemplarily, Figure 5a A schematic diagram of battery capacity attenuation of a lithium battery at different charging temperatures provided by an embodiment of the present invention. Figure 5b A schematic diagram of battery capacity attenuation of a lithium battery at different charging rates provided by an embodiment of the present invention; Figure 5a and Figure 5b It can be seen that the lower the temperature of a lithium battery, the lower its charge capacity. At the same current, the lower the temperature, the more severe the impact of lithium plating on the battery cell. At the same temperature, the higher the charging current, the more severe the impact of lithium plating on the battery cell. Based on the lithium battery's charging characteristics data, the target heating current and target charging current are determined to achieve the fastest temperature increase for the lithium battery at the current temperature without causing lithium plating.

[0042] Optionally, before determining the target charging current and target heating current according to the charging characteristic data of the lithium battery when it is determined that the charging conditions for the lithium battery are met according to the current battery voltage and the current external power supply voltage, it also includes: obtaining the current SOC of the lithium battery; when it is determined that the charging conditions for the lithium battery are met according to the current battery voltage and the current external power supply voltage, determining the target charging current and target heating current according to the charging characteristic data of the lithium battery, including: when it is determined that the charging conditions for the lithium battery are met according to the current battery voltage and the current external power supply voltage, determining the maximum allowable charging current at the current temperature at which the lithium battery does not produce lithium deposition according to the charging characteristic data of the lithium battery; determining the target internal resistance of the lithium battery corresponding to the current SOC of the lithium battery at the current temperature according to the internal resistance characteristic data of the lithium battery; and within the range of the maximum allowable charging current, determining the target charging current and target heating current that will cause the lithium battery to heat up the fastest according to the target internal resistance.

[0043] In an embodiment of the present invention, the MCU obtains the current SOC of the lithium battery. When it is determined that the charging conditions for the lithium battery are met based on the current battery voltage and the current external power supply voltage, the maximum allowable charging current that prevents the lithium battery from producing lithium deposition at the current temperature is determined based on the charging characteristic data of the lithium battery. For example, the internal resistance characteristic data of the lithium battery is obtained. Figure 6 This is a schematic diagram of the internal resistance characteristic data of a lithium battery provided by an embodiment of the present invention. Figure 6As shown, at the same depth of discharge, the lower the temperature, the greater the battery impedance; at the same temperature, the greater the depth of discharge, the greater the impedance; when the battery is working, the internal resistance changes with temperature and depth of discharge, and it is not a linear relationship, so the heat generated by the battery is not constant. Then, according to the internal resistance characteristic data of the lithium battery, the current internal resistance (i.e., the target internal resistance) of the lithium battery is determined when the power of the lithium battery is the current power SOC at the current temperature. Since lithium plating occurs in a lithium battery, the charging capacity of the lithium battery will be attenuated, wherein the more serious the lithium plating, the more serious the charging capacity attenuation of the lithium battery. Therefore, in order to avoid the charging capacity attenuation of the lithium battery, the charging current of the lithium battery needs to be controlled within the maximum allowable charging current range. In addition, since the higher the temperature, the higher the charging capacity of the lithium battery, and the charging and heating processes of the lithium battery will cause the lithium battery to heat up, therefore, in order to enable the lithium battery to obtain a higher charging capacity, the target charging current and target heating current that make the lithium battery heat up the fastest are determined according to the target internal resistance; wherein, the target charging current is within the maximum allowable charging current range, that is, the target charging current is less than or equal to the maximum allowable charging current. The target charging current and target heating current at which the lithium battery heats up the fastest can be understood as the target charging current and target heating current when the sum of the lithium battery charging temperature rise rate and the lithium battery heating temperature rise rate is the largest.

[0044] Optionally, within the maximum allowable charging current range, determining the target charging current and target heating current that will cause the lithium battery to heat up the fastest based on the target internal resistance includes: determining energy allocation information between the charging temperature rise rate and the heating temperature rise rate of the lithium battery and the charging energy and heating energy at the maximum; and determining the target charging current and target heating current within the maximum allowable charging current range based on the target internal resistance and the energy allocation information. In an embodiment of the present invention, the external power supply power is fixed, that is, the external power supply energy is fixed, and a portion of the power supply energy can be used to charge the lithium battery, and another portion of the power supply energy can be used to heat the lithium battery. The charging temperature rise rate of the lithium battery is the ratio of the charging power of the lithium battery to the specific heat capacity of the lithium battery, and the heating power of the lithium battery is the ratio of the heating power of the lithium battery to the specific heat capacity of the lithium battery. Therefore, energy allocation information between the charging temperature rise rate and the heating temperature rise rate of the lithium battery and the charging energy and heating energy at the maximum can be determined. The energy allocation information between charging energy and heating energy can be understood as the ratio of charging power to heating power, or as the allocated values ​​of charging power and heating power. Since power is the product of the square of the current and the internal resistance, the target charging current and target heating current can be determined based on the target internal resistance and energy allocation information.

[0045] S330: Charge the lithium battery based on the target charging current, and heat the lithium battery based on the target heating current.

[0046] In an embodiment of the present invention, the MCU controls the charging MOS tube to charge the lithium battery based on the target charging current, and controls the heating module to heat the lithium battery based on the target heating current. Optionally, charging the lithium battery based on the target charging current and heating the lithium battery based on the target heating current include: controlling the PWM duty cycle of the PWM drive circuit so that the charging MOS tube charges the lithium battery based on the target charging current, and the heating module heats the lithium battery based on the target heating current. Exemplarily, the first PWM duty cycle of the PWM drive circuit can be calculated based on the target charging current and the target heating current, and the duty cycle of the PWM drive circuit can be controlled to be adjusted to the first PWM duty cycle, so that the charging MOS tube charges the lithium battery based on the target charging current, and the heating module heats the lithium battery based on the target heating current.

[0047] A battery management method according to an embodiment of the present invention is applied to a battery management system, which includes a lithium battery and a voltage acquisition circuit. The method includes: in response to a battery management event being triggered, acquiring the current battery voltage and the current external power supply voltage of the lithium battery through the voltage sampling circuit, and obtaining the current temperature of the lithium battery; when it is determined that the charging conditions for the lithium battery are met based on the current battery voltage and the current external power supply voltage, determining a target charging current and a target heating current based on the charging characteristic data of the lithium battery; wherein the target charging current is the charging current that causes the lithium battery to heat up the fastest at the current temperature and prevents the lithium battery from producing lithium plating; charging the lithium battery based on the target charging current, and heating the lithium battery based on the target heating current. The technical solution provided by the embodiment of the present invention not only solves the technical problems of the lithium battery heating function being turned on only when the lithium battery temperature is lower than a fixed temperature threshold, and the inability to charge the lithium battery during heating, resulting in waste of photovoltaic power, but also, when it is determined that sufficient external charging conditions are available, the lithium battery can be charged in real time based on the target charging current according to the battery temperature while utilizing external electric heating, provided that lithium plating does not occur in the lithium battery. This can minimize waste of external electrical energy, and can also make the internal temperature of the battery rise faster, reach a higher temperature as soon as possible, and resume charging with a larger current.

[0048] In some embodiments, when it is determined based on the current battery voltage and the current external supply voltage that the charging condition for the lithium battery is not met, a target heating voltage that maximizes the battery life is determined based on the current temperature and the current state of charge (SOC) of the lithium battery; the lithium battery is controlled to discharge, and the lithium battery is heated based on the target heating voltage during the discharge of the lithium battery. For example, when the voltage difference between the current external supply voltage and the current battery voltage is less than a preset voltage threshold, it can be determined that the charging condition for the lithium battery is not met. In this case, the lithium battery is in an unloaded or discharged state. Since the lower the temperature of a lithium battery, the lower the discharge capacity, the lithium battery can be heated when the charging condition is not met to increase the discharge capacity of the lithium battery. However, at a certain moment, the discharge capacity of the lithium battery is fixed. If a small amount of energy is allocated to heating the lithium battery, the lithium battery will not heat up quickly, resulting in a shorter battery life. If a large amount of energy is allocated to heating the lithium battery, the discharge capacity of the lithium battery will be used for heating the lithium battery, which will also result in a shorter battery life. Therefore, when it is determined that the charging conditions for the lithium battery are not met, the target heating voltage that maximizes the battery's battery life is determined based on the battery's current temperature and current state of charge (SOC). The battery is then controlled to discharge, and during the discharge process, it is heated based on the target heating voltage. This arrangement effectively increases the battery's battery life.

[0049] Optionally, when it is determined based on the current battery voltage and the current external power supply voltage that the charging conditions for the lithium battery are not met, the target heating voltage that maximizes the battery life of the lithium battery is determined based on the current temperature and the current charge SOC of the lithium battery, including: when it is determined based on the current battery voltage and the current external power supply voltage that the charging conditions for the lithium battery are not met, the discharge capacity of the lithium battery is determined based on the discharge characteristic data of the lithium battery at the current temperature when the charge of the lithium battery is the current charge SOC; and the target heating voltage that maximizes the battery life of the lithium battery is determined based on the discharge capacity and the current battery voltage.

[0050] In an embodiment of the present invention, the discharge characteristic data of the lithium battery is obtained, for example, Figure 7 A schematic diagram of discharge characteristic data of a lithium battery provided by an embodiment of the present invention, such as Figure 7As shown, the lower the temperature, the lower the discharge capacity. When it is determined that the charging conditions for the lithium battery are not met based on the current battery voltage and the current external power supply voltage, the discharge capacity Q of the lithium battery is determined according to the discharge characteristic data of the lithium battery when the power of the lithium battery is the current power SOC at the current temperature, and then the target heating voltage that makes the lithium battery life the longest is determined based on the discharge capacity and the current battery voltage. Since the battery life of the lithium battery is T=Q / (U*I), where Q represents the discharge capacity of the lithium battery, U represents the current battery voltage of the lithium battery, and I represents the total current of the lithium battery, where the total current of the lithium battery is the sum of the heating current and the load consumption current. Since the external load (i.e., the heating module) works at constant power and the heating module is a constant resistance heating, the load consumption current is a fixed value. Since the load consumption current is a fixed value and the current battery voltage of the lithium battery is a fixed value, in order to improve the battery life of the lithium battery, only the heating voltage or heating current can be adjusted. Since the greater the heating current, the faster the lithium battery heats up, which leads to a larger discharge capacity Q of the lithium battery, that is, the discharge capacity Q of the lithium battery changes in conjunction with the change of the heating current. Therefore, the target heating voltage (which can also be converted into heating current) that can make the lithium battery last the longest is determined, that is, the heating current when MAX{Q(SOC, temperature) / (U*I)} is taken (the heating current can be converted into the target heating voltage).

[0051] Optionally, controlling the discharge of the lithium battery and heating the lithium battery based on the target heating voltage during the discharge of the lithium battery includes: controlling the discharge MOS tube to turn on to discharge the lithium battery, and during the discharge of the lithium battery, controlling the PWM duty cycle of the PWM drive circuit so that the heating module heats the lithium battery based on the target heating voltage. In an embodiment of the present invention, the discharge MOS tube is controlled to turn on so that the lithium battery discharges through the discharge MOS tube, and a second PWM duty cycle of the PWM drive current is calculated based on the target heating voltage, so that during the discharge of the lithium battery, the PWM duty cycle of the PWM drive circuit is controlled to be the second PWM duty cycle so that the heating module heats the lithium battery based on the target heating voltage, thereby effectively improving the battery life of the lithium battery.

[0052] Example 2

[0053] Figure 8 This is a structural diagram of a battery management device provided in the second embodiment of the present invention. The battery management device shown is applied to a battery management system. The battery management system includes a lithium battery and a voltage acquisition circuit. Figure 8 As shown, the device includes:

[0054] a voltage acquisition module 810 for acquiring the current battery voltage and the current external power supply voltage of the lithium battery and the current temperature of the lithium battery through the voltage sampling circuit in response to a battery management event being triggered;

[0055] a target current determination module 820 for determining a target charging current and a target heating current based on the charging characteristic data of the lithium battery when it is determined that the charging conditions for the lithium battery are met based on the current battery voltage and the current external power supply voltage; wherein the target charging current is the charging current that causes the lithium battery to heat up most rapidly at the current temperature and prevents lithium deposition in the lithium battery;

[0056] The battery charging management module 830 is configured to charge the lithium battery based on the target charging current and heat the lithium battery based on the target heating current.

[0057] Optionally, the device further includes:

[0058] a state of charge (SOC) acquisition module, configured to, when it is determined that a charging condition for the lithium battery is met according to the current battery voltage and the current external power supply voltage, acquire a current state of charge (SOC) of the lithium battery before determining a target charging current and a target heating current according to the charging characteristic data of the lithium battery;

[0059] The target current determination module includes:

[0060] a maximum allowable charging current determining unit, configured to determine, based on the charging characteristic data of the lithium battery, a maximum allowable charging current for preventing lithium deposition in the lithium battery at the current temperature when it is determined that the charging condition for the lithium battery is met based on the current battery voltage and the current external power supply voltage;

[0061] a target internal resistance determining unit, configured to determine a target internal resistance of the lithium battery corresponding to the current state of charge (SOC) of the lithium battery at the current temperature based on the internal resistance characteristic data of the lithium battery;

[0062] The target current determination unit is used to determine, within the maximum allowable charging current range, a target charging current and a target heating current that will cause the lithium battery to heat up fastest according to the target internal resistance.

[0063] Optionally, the target current determining unit is configured to:

[0064] Determining energy allocation information between charging energy and heating energy when the sum of the charging temperature rise rate and the heating temperature rise rate of the lithium battery is maximized;

[0065] Within the maximum allowable charging current range, a target charging current and a target heating current are determined according to the target internal resistance and the energy distribution information.

[0066] Optionally, the battery charging management module is used to:

[0067] By controlling the PWM duty cycle of the PWM driving circuit, the charging MOS tube charges the lithium battery based on the target charging current, and the heating module heats the lithium battery based on the target heating current.

[0068] Optionally, the device further includes:

[0069] a heating voltage acquisition module, configured to determine, when it is determined based on the current battery voltage and the current external power supply voltage that a charging condition for the lithium battery is not satisfied, a target heating voltage that maximizes the battery life of the lithium battery based on the current temperature and the current state of charge (SOC) of the lithium battery;

[0070] The battery discharge management module is used to control the discharge of the lithium battery and heat the lithium battery based on the target heating voltage during the discharge of the lithium battery.

[0071] Optionally, the heating voltage acquisition module is used to:

[0072] When it is determined that the charging condition for the lithium battery is not met according to the current battery voltage and the current external power supply voltage, the discharge capacity of the lithium battery is determined according to the discharge characteristic data of the lithium battery when the power of the lithium battery is the current power SOC at the current temperature;

[0073] A target heating voltage that maximizes the battery life of the lithium battery is determined according to the dischargeable capacity and the current battery voltage.

[0074] Optionally, the battery discharge management module is configured to:

[0075] The discharge MOS tube is controlled to be turned on to discharge the lithium battery, and during the discharge process of the lithium battery, the PWM duty cycle of the PWM drive circuit is controlled so that the heating module heats the lithium battery based on the target heating voltage.

[0076] The battery management device provided in the embodiment of the present invention can execute the battery management method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0077] Example 3

[0078] Figure 9A schematic diagram of a battery management system 10 that can be used to implement an embodiment of the present invention is shown. The battery management system is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The battery management system can also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0079] like Figure 9 As shown, the battery management system 10 includes a lithium battery and a voltage acquisition circuit, as well as at least one processor 11 and memory, such as a read-only memory (ROM) 12 and a random access memory (RAM) 13, in communication with the at least one processor 11. The memory stores computer programs that can be executed by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the read-only memory (ROM) 12 or loaded from the storage unit 18 into the random access memory (RAM) 13. The RAM 13 can also store various programs and data required for the operation of the battery management system 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0080] Multiple components in the battery management system 10 are connected to the I / O interface 15, including an input unit 16, such as a keyboard and mouse; an output unit 17, such as various types of displays and speakers; a storage unit 18, such as a magnetic disk and optical disk; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the battery management system 10 to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks.

[0081] The processor 11 may be any general-purpose and / or specialized processing component with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various specialized artificial intelligence (AI) computing chips, various processors that run machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the battery management method.

[0082] In some embodiments, the battery management method can be implemented as a computer program tangibly embodied in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on battery management system 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the battery management method described above can be performed. Alternatively, in other embodiments, processor 11 can be configured to execute the battery management method in any other suitable manner (e.g., via firmware).

[0083] Various embodiments of the systems and techniques described herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system-on-chip systems (SOCs), programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that are executable and / or interpreted on a programmable system that includes at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0084] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the computer program is executed by the processor, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The computer program may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0085] In the context of the present invention, computer-readable storage media can be tangible media that can contain or store a computer program for use with an instruction execution system, device or equipment or used in combination with an instruction execution system, device or equipment. Computer-readable storage media can include but are not limited to electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, computer-readable storage media can be machine-readable signal media. More specific examples of machine-readable storage media can include electrical connections based on one or more lines, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0086] To provide user interaction, the systems and techniques described herein can be implemented on a battery management system that includes: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the battery management system. Other types of devices can also be used to provide user interaction; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form, including acoustic input, voice input, or tactile input.

[0087] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0088] A computing system may include clients and servers. The clients and servers are typically remote from each other and typically interact via a communication network. This client-server relationship arises through computer programs running on the respective computers, creating a client-server relationship. The server may be a cloud server, also known as a cloud computing server or cloud host. This server is a hosting product within the cloud computing service ecosystem that addresses the management difficulties and limited scalability of traditional physical hosting and VPS services.

[0089] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved. This is not limited herein.

[0090] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A battery management method, characterized in that: Applied to a battery management system, the battery management system includes a lithium battery and a voltage acquisition circuit, and the method includes: In response to a battery management event being triggered, collecting the current battery voltage and the current external power supply voltage of the lithium battery through the voltage sampling circuit, and obtaining the current temperature of the lithium battery; When it is determined that the charging conditions for the lithium battery are met according to the current battery voltage and the current external power supply voltage, a target charging current and a target heating current are determined according to the charging characteristic data of the lithium battery; wherein the target charging current is the charging current that causes the lithium battery to heat up fastest at the current temperature and prevents lithium deposition in the lithium battery; The lithium battery is charged based on the target charging current, and the lithium battery is heated based on the target heating current.

2. The method according to claim 1, characterized in that When it is determined according to the current battery voltage and the current external power supply voltage that the charging condition for the lithium battery is met, before determining the target charging current and the target heating current according to the charging characteristic data of the lithium battery, the method further includes: Obtaining the current state of charge (SOC) of the lithium battery; When it is determined that a charging condition for the lithium battery is met according to the current battery voltage and the current external power supply voltage, determining a target charging current and a target heating current according to charging characteristic data of the lithium battery includes: When it is determined that the charging condition for the lithium battery is met according to the current battery voltage and the current external power supply voltage, determining, according to the charging characteristic data of the lithium battery, a maximum allowable charging current at the current temperature at which the lithium battery does not produce lithium deposition; Determining a target internal resistance of the lithium battery corresponding to the current state of charge (SOC) of the lithium battery at the current temperature based on the internal resistance characteristic data of the lithium battery; Within the maximum allowable charging current range, a target charging current and a target heating current that cause the lithium battery to heat up fastest are determined according to the target internal resistance.

3. The method according to claim 2, characterized in that Determining, within the maximum allowable charging current range, a target charging current and a target heating current that cause the lithium battery to heat up fastest according to the target internal resistance, includes: Determining energy allocation information between charging energy and heating energy when the sum of the charging temperature rise rate and the heating temperature rise rate of the lithium battery is maximized; Within the maximum allowable charging current range, a target charging current and a target heating current are determined according to the target internal resistance and the energy distribution information.

4. The method according to claim 1, wherein Charging the lithium battery based on the target charging current and heating the lithium battery based on the target heating current, comprising: By controlling the PWM duty cycle of the PWM driving circuit, the charging MOS tube charges the lithium battery based on the target charging current, and the heating module heats the lithium battery based on the target heating current.

5. The method according to claim 1, wherein Also includes: When it is determined that the charging condition for the lithium battery is not met according to the current battery voltage and the current external power supply voltage, determining a target heating voltage that maximizes the battery life of the lithium battery according to the current temperature and the current state of charge (SOC) of the lithium battery; The lithium battery is controlled to discharge, and during the discharge of the lithium battery, the lithium battery is heated based on the target heating voltage.

6. The method according to claim 5, characterized in that When it is determined that the charging condition for the lithium battery is not met according to the current battery voltage and the current external power supply voltage, determining a target heating voltage that maximizes the battery life of the lithium battery according to the current temperature and the current state of charge (SOC) of the lithium battery includes: When it is determined that the charging condition for the lithium battery is not met according to the current battery voltage and the current external power supply voltage, the discharge capacity of the lithium battery is determined according to the discharge characteristic data of the lithium battery when the power of the lithium battery is the current power SOC at the current temperature; A target heating voltage that maximizes the battery life of the lithium battery is determined according to the dischargeable capacity and the current battery voltage.

7. The method according to claim 5, characterized in that Controlling the discharge of the lithium battery and heating the lithium battery based on the target heating voltage during the discharge of the lithium battery, comprising: The discharge MOS tube is controlled to be turned on to discharge the lithium battery, and during the discharge process of the lithium battery, the PWM duty cycle of the PWM drive circuit is controlled so that the heating module heats the lithium battery based on the target heating voltage.

8. A battery management device, characterized in that: Applied to a battery management system, the battery management system includes a lithium battery and a voltage acquisition circuit, the device includes: a voltage acquisition module, configured to acquire the current battery voltage and the current external power supply voltage of the lithium battery through the voltage sampling circuit in response to a battery management event being triggered, and to obtain the current temperature of the lithium battery; a target current determination module, configured to determine a target charging current and a target heating current based on the charging characteristic data of the lithium battery when it is determined that the charging conditions for the lithium battery are met based on the current battery voltage and the current external power supply voltage; wherein the target charging current is the charging current that causes the lithium battery to heat up fastest at the current temperature and prevents lithium deposition in the lithium battery; A battery charging management module is configured to charge the lithium battery based on the target charging current and heat the lithium battery based on the target heating current.

9. A battery management system, characterized in that: The battery management system includes a lithium battery and a voltage acquisition circuit, and the battery management system also includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor. The computer program is executed by the at least one processor to enable the at least one processor to perform the battery management method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the battery management method according to any one of claims 1 to 7 when executed.

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