A charging control method

Abstract

The application provides a charging control method. The charging control method comprises: obtaining an operating parameter of a target battery; calculating a basic pressure value reflecting the influence of pressure under the current operating condition of the target battery and at least one correction index value reflecting the influence of additional pressure under abnormal charging and discharging or static conditions according to the operating parameter; performing weighted calculation on the basic pressure value and the correction index value to obtain a current pressure index of the target battery; comparing the current pressure index with a preset threshold value, and triggering down-regulation control of a charging strategy when the current pressure index is greater than the preset threshold value, so as to reduce the charging rate or the charging power. The application scheme can adaptively adjust the charging strategy according to the actual operating condition of the battery during the charging process, and realizes the dynamic balance between the charging efficiency and the safety of the battery.

Description

Technical Field

[0001] This invention relates to the field of battery management system technology, and in particular to a charging control method. Background Technology

[0002] Currently, with the widespread application of lithium-ion batteries in mobile terminals, electric vehicles, and energy storage systems, how to extend battery life while ensuring users' fast charging experience has become an urgent problem to be solved in the design of battery management systems.

[0003] In existing technologies, most mainstream fast charging control strategies employ static threshold judgment mechanisms. For example, when the state of health (SOH) of the battery is detected to be below a certain set value, the fast charging function is automatically disabled, or a simple sliding window is used to statistically analyze the last three charge and discharge behaviors, calculate the average rate, and determine whether fast charging is allowed. Some high-end devices have also begun to introduce AI algorithms to predict SOH trends, but their core control logic is still mainly based on a single dimension, such as temperature or cycle count, lacking a comprehensive evaluation of the user's charging and discharging behavior patterns. Summary of the Invention

[0004] One objective of this invention is to enable the charging process to adaptively adjust the charging strategy according to the actual operating conditions of the battery, thereby achieving a dynamic balance between charging efficiency and battery safety.

[0005] According to the present invention, a charging control method is provided, comprising the following steps:

[0006] Obtain the operating parameters of the target battery, including the health status of the target battery, the temperature parameters of the current charging process, the cumulative number of cycles, the historical charging and discharging behavior, and the corresponding charge and discharge rate;

[0007] Based on the operating parameters of the target battery, a base pressure value reflecting the pressure impact under the current operating conditions of the target battery and at least one correction index value reflecting the additional pressure impact under abnormal charging / discharging or static conditions are calculated.

[0008] The current pressure index of the target battery is obtained by weighting the base pressure value and the at least one correction index value.

[0009] The current pressure index is compared with a preset threshold, and when the current pressure index is greater than the preset threshold, the charging strategy is adjusted downward to reduce the charging rate or charging power.

[0010] In some embodiments, the method for calculating the baseline pressure value includes the following steps:

[0011] Calculate multiple basic characteristic parameters for reflecting the pressure influence under the current operating condition of the target battery according to the temperature parameter, cumulative cycle number, historical charge-discharge behavior and corresponding charge-discharge rate of the current charging process;

[0012] Calculate an adjustment coefficient according to the health degree of the target battery;

[0013] Perform weighted calculation on the multiple basic characteristic parameters and multiply the calculation result by the adjustment coefficient to obtain the basic pressure value of the target battery.

[0014] In some embodiments, the basic characteristic parameters include a charging pressure parameter and a discharging pressure parameter, and the calculation methods of the charging pressure parameter and the discharging pressure parameter include the following steps:

[0015] Obtain the attenuation coefficient corresponding to the charge-discharge type, the charge-discharge rates of the most recent n charge-discharge behaviors, and the time intervals from the most recent n charge-discharge behaviors to the current moment, where n≥2;

[0016] Respectively determine the corresponding charging pressure parameter and discharging pressure parameter based on the attenuation coefficient, operating rate and time interval according to a calculation method including a time decay weight.

[0017] In some embodiments, the basic characteristic parameters include a temperature pressure parameter, and the calculation method of the temperature pressure parameter includes the following steps:

[0018] Determine the current average temperature T according to the temperature parameter of the current charging process

[0024] , , , c , ,

[0023] ;

[0019] According to the current average temperature T avg Determine the temperature pressure parameter T according to the following formula pressure ,

[0020] ,

[0021] where a1, a2, a3, b1, b2, c1, c2 and c3 are all constants, and satisfy a1 < a2 < a3, c1, c2 and c3 are all greater than 0, and b1 and b2 are initial pressure coefficients corresponding to temperature intervals.

[0022] In some embodiments, the basic characteristic parameters include a cycle number pressure parameter, and the calculation formula of the cycle number pressure parameter N pressure is:

[0023] ,

[0024] where N c represents the cumulative cycle number, and k1 and k2 are both constants. The preset cycle interval value is defined, and k1, k2, and All are positive numbers. This indicates the cumulative number of iterations and the preset iteration interval. The result of division is the integer part. This represents the result of modulo the cumulative number of iterations with respect to the preset iteration interval.

[0025] In some embodiments, the formula for calculating the adjustment coefficient is:

[0026] ,

[0027] Among them, K dyn k3 is the adjustment coefficient, k3 is the aging tolerance coefficient, and SOH is the health of the target battery.

[0028] In some embodiments, the correction index value includes a first penalty value for imposing constraints on continuous fast charging behavior, and the calculation method for the first penalty value includes the following steps:

[0029] Obtain the target charging rate and the corresponding time interval for the m most recent charging behaviors of the target battery;

[0030] When the target charging rate is greater than or equal to the first preset charging rate threshold and the corresponding time interval is less than the first preset time threshold, the first penalty value is set to the first preset positive value.

[0031] If there is at least one standard charging behavior or resting behavior between two adjacent charging behaviors in the m charging behaviors, the first penalty value is set to zero.

[0032] Otherwise, the first penalty value will be set to a preset negative value.

[0033] In some embodiments, the correction index value includes a second penalty value for imposing constraints on charge-discharge coupling behavior, the second penalty value being calculated by the following steps:

[0034] Get the charging rate of the current charging behavior, the discharge rate of the most recent complete discharge behavior, and the time interval between the two behaviors;

[0035] When the most recent discharge rate is greater than or equal to a preset discharge rate threshold and the current charging rate is greater than or equal to a second preset charging rate threshold, and the time interval is less than or equal to a second preset time threshold, the second penalty value is set to a second preset positive value.

[0036] Otherwise, the second penalty value will be set to zero.

[0037] In some embodiments, the correction index value includes a first compensation value for rewarding the cooling behavior of the target battery, and the calculation method for the first compensation value includes the following steps:

[0038] Obtain the time interval between the most recent discharge behavior and the current charging behavior;

[0039] When the time interval is greater than or equal to the required cooling period of the battery, the sum of the first penalty value and the second penalty value is multiplied by the cooling coefficient and assigned to the first compensation value;

[0040] Otherwise, the first compensation value is set to zero.

[0041] In some embodiments, the preset threshold is adjusted based on the current health of the target battery.

[0042] According to the present invention, by setting a correction index value in addition to the basic pressure value, an additional correction is made for the pressure impact on the target battery under abnormal charging and discharging behavior or non-steady-state operating conditions. This makes the pressure assessment results more accurate and comprehensive in reflecting the actual pressure state of the target battery. When the current pressure index exceeds a preset threshold, the control system automatically triggers a downward adjustment control of the charging strategy to proactively protect the target battery before it is subjected to excessive charging pressure, preventing performance degradation or safety risks caused by excessive stress accumulation. Furthermore, since the operating parameters include information such as the health of the target battery, temperature parameters during the charging process, cumulative cycle count, and historical charging and discharging behavior, the system can dynamically assess and respond in real time to the pressure state of the target battery based on the operating parameters. This allows the charging process to adaptively adjust the charging strategy according to the actual operating conditions of the battery, achieving a dynamic balance between charging efficiency and battery safety.

[0043] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Attached Figure Description

[0044] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0045] Figure 1 A schematic flowchart of a charging control method according to an embodiment of the present invention is shown;

[0046] Figure 2A schematic flowchart illustrating a method for calculating a baseline pressure value according to an embodiment of the present invention is shown;

[0047] Figure 3 A schematic flowchart of a method for calculating charging pressure parameters according to an embodiment of the present invention is shown;

[0048] Figure 4 A schematic flowchart illustrating a method for calculating discharge pressure parameters according to an embodiment of the present invention is shown.

[0049] Figure 5 A schematic flowchart illustrating a method for calculating temperature and pressure parameters according to an embodiment of the present invention is shown. Detailed Implementation

[0050] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0051] The terms “comprising” and “having”, and any variations thereof, used in this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0052] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0053] Figure 1 A schematic flowchart of a charging control method according to an embodiment of the present invention is shown. This charging control method is executed by a control module of a charging system. This control module can be applied to charging devices for consumer electronics, energy storage devices, power tools, or other battery-powered devices with charge / discharge management functions, for monitoring and controlling the charging process of a target battery. Figure 1 As shown, the charging control method includes:

[0054] Step S1: Obtain the operating parameters of the target battery. The operating parameters include the health status of the target battery, the temperature parameters of the current charging process, the cumulative number of cycles, the historical charging and discharging behavior, and the corresponding charging and discharging rate.

[0055] Step S2: Based on the operating parameters of the target battery, calculate the basic pressure value that reflects the pressure impact under the current operating conditions of the target battery and at least one correction index value that reflects the additional pressure impact under abnormal charging / discharging or static conditions.

[0056] Step S3: Weight the base pressure value and at least one correction index value to obtain the current pressure index of the target battery.

[0057] Step S4: Compare the current pressure index with a preset threshold, and trigger the downward control of the charging strategy when the current pressure index is greater than the preset threshold, so as to reduce the charging rate or charging power.

[0058] According to the present invention, by setting a correction index value in addition to the basic pressure value, an additional correction is made for the pressure impact on the target battery under abnormal charging and discharging behavior or non-steady-state operating conditions. This makes the pressure assessment results more accurate and comprehensive in reflecting the actual pressure state of the target battery. When the current pressure index exceeds a preset threshold, the control system automatically triggers a downward adjustment control of the charging strategy to proactively protect the target battery before it is subjected to excessive charging pressure, preventing performance degradation or safety risks caused by excessive stress accumulation. Furthermore, since the operating parameters include information such as the health of the target battery, temperature parameters during the charging process, cumulative cycle count, and historical charging and discharging behavior, the system can dynamically assess and respond in real time to the pressure state of the target battery based on the operating parameters. This allows the charging process to adaptively adjust the charging strategy according to the actual operating conditions of the battery, achieving a dynamic balance between charging efficiency and battery safety.

[0059] In step S1, the operating parameters of the target battery can include three core parameters: battery state parameters, charge / discharge history parameters, and environmental parameters. The battery state parameters characterize the health and usage status of the target battery, including its remaining capacity, State of Health (SOH), charging temperature, and cumulative cycle count. State of Health represents the ratio of current battery capacity to initial capacity. The cumulative cycle count reflects the frequency of battery use. The cumulative charge / discharge cycle count characterizes the total number of charge / discharge cycles accumulated by the target battery. One complete charge / discharge process, including one charge and one discharge, is considered one cycle. For example, the cumulative charge / discharge cycle count can be 150, indicating that the target battery has completed 150 complete charge / discharge cycles. This value is within the charge / discharge cycle range corresponding to the target battery's design life.

[0060] Historical charge / discharge parameters reflect the recent charge / discharge behavior and characteristics of the target battery, including the rates and corresponding time intervals of the most recent charge and discharge operations, to analyze the cumulative impact of continuous high-rate charge / discharge behavior. The most recent charge / discharge operations can be selected as at least two and no more than five recent operations, or operations within the most recent 24 to 72 hours. This effectively captures continuous high-rate charge / discharge behavior while avoiding computational redundancy due to excessive historical data. The charge / discharge rate represents the rate of charge / discharge per unit time.

[0061] Environmental parameters reflect the external conditions and resting state of the target battery, including the current ambient temperature and resting time. By acquiring these operating parameters, the system can comprehensively evaluate the current state, historical load, and environmental conditions of the target battery, providing a basis for the subsequent calculation of basic pressure values, correction index values, and pressure indices, thereby achieving dynamic monitoring and intelligent control of the charging process.

[0062] In step S2, the baseline pressure value, reflecting the impact of pressure under the current operating conditions of the target battery, is a quantitative index obtained by calculating the operating parameters of the target battery. It is used to comprehensively characterize the electrochemical and thermal stresses experienced by the target battery under current charge / discharge behavior and recent usage conditions. This baseline pressure value can reflect the potential impact of factors such as charge rate, discharge rate, temperature, and cycle count on the battery's internal stress, capacity decay, and aging rate. It can also serve as a basis for determining whether to adjust the charging strategy, such as triggering a current-limiting charging mode, thereby achieving dynamic assessment and protection of the target battery's current operating state.

[0063] The indicator reflecting the impact of additional pressure under abnormal charging / discharging or static conditions refers to a quantifiable correction index for the extra electrochemical and thermal stress experienced by the target battery under atypical or unsteady-state usage conditions. This correction index value is primarily used to supplement the cumulative damage that may be caused by continuous high-rate charging, rapid discharging followed immediately by fast charging, or prolonged static storage, thereby supplementing the risks in special usage scenarios that the basic pressure value cannot fully reflect. Through this correction index value, the system can take timely protective measures before the target battery is subjected to abnormal pressure, such as limiting the fast charging rate or extending the charging interval, achieving active protection and dynamic control of the battery.

[0064] In step S3, the current pressure index of the target battery is used to quantitatively assess the pressure state of the target battery under continuous charge and discharge behavior, reflecting the cumulative pressure level experienced by the target battery within a given operating cycle. A higher pressure index indicates a higher stress state of the target battery, and a more stringent charging control strategy.

[0065] Figure 2A schematic flowchart illustrating a method for calculating a baseline pressure value according to an embodiment of the present invention is shown. Figure 2 As shown, the calculation method for this basic pressure value includes:

[0066] Step S21: Based on the temperature parameters of the current charging process, the cumulative number of cycles, the historical charging and discharging behavior and the corresponding charging and discharging rate, calculate several basic characteristic parameters that reflect the pressure influence under the current operating conditions of the target battery.

[0067] Step S22: Calculate the adjustment coefficient based on the health status of the target battery;

[0068] Step S23: Perform weighted calculations on multiple basic characteristic parameters, and multiply the calculation results by the adjustment coefficient to obtain the basic pressure value of the target battery.

[0069] In step S21, reflecting the pressure impact under the current operating conditions of the target battery refers to comprehensively evaluating the overall stress level of the target battery under the current operating conditions based on factors such as the actual operating conditions of the target battery during the charging process, such as temperature, number of cycles, charge / discharge rate, and historical charge / discharge behavior. This is used to quantitatively reflect the degree of impact of the operating conditions on potential risks such as battery performance degradation, heat accumulation, and structural aging.

[0070] In some embodiments, the basic characteristic parameters may include charging pressure parameters and discharging pressure parameters. Figure 3 A schematic flowchart illustrating a method for calculating charging pressure parameters according to an embodiment of the present invention is shown. Figure 3 As shown, the calculation method for this charging pressure parameter includes:

[0071] Step S211: Obtain the charging attenuation coefficient, the charging rate of the most recent n charging behaviors, and the time interval between the most recent n charging behaviors and the current time, where n≥2;

[0072] Step S212: Based on the charging attenuation coefficient, operating rate, and time interval, determine the corresponding charging pressure parameters according to a calculation method that includes time attenuation weight.

[0073] In step S211, the charging attenuation coefficient is a preset value used to characterize the attenuation effect of time intervals on the weight of historical charging behavior. In one example, the charging attenuation coefficient can be set to 0.98, or it can be adjusted within the range of 0.95-0.99 according to different battery types, capacities, and thermal management characteristics. In a preferred embodiment, the value of n ranges from 2 to 5. When n is small, the calculation results can quickly reflect the impact of recent high-frequency charging behavior. When n is large, it can smooth historical data and reduce the fluctuation impact of a single abnormal charging behavior on the calculation results. The value of n can be dynamically adjusted according to the usage scenario of the target battery. For example, for consumer electronics batteries, the most recent 3-5 charging behaviors can be selected to improve the model's sensitivity to short-term fast charging behavior of users. For energy storage system or power tool batteries, the most recent 2-3 charging behaviors can be selected to reduce computational complexity and take into account real-time performance.

[0074] In step S212, the formula for calculating the time decay weight is as follows:

[0075] ,

[0076] In the formula, C pressure This represents the charging pressure parameter, α represents the charging attenuation coefficient, and C... i Let t represent the charging rate of the i-th charging action out of the most recent n charging actions. i This represents the time interval between the i-th charging action in the most recent n-th charging action and the current time.

[0077] Figure 4 A schematic flowchart illustrating a method for calculating discharge pressure parameters according to an embodiment of the present invention is shown. Figure 4 As shown, the calculation method for this discharge pressure parameter includes:

[0078] Step S213: Obtain the discharge attenuation coefficient, the charging rate of the most recent n discharge behaviors, and the time interval between the most recent n discharge behaviors and the current time, where n≥2;

[0079] Step S214: Based on the discharge attenuation coefficient, operating rate, and time interval, determine the corresponding discharge pressure parameters according to the calculation method that includes time attenuation weight.

[0080] In step S213, the discharge decay coefficient is a preset value used to characterize the decay effect of time interval on the weight of historical discharge behavior. In one example, the discharge decay coefficient can be set to 0.97, or it can be adjusted within the range of 0.94-0.98 according to different battery types, capacities, and thermal management characteristics. In a preferred embodiment, the value of n ranges from 2 to 5. When n is a smaller value, the calculation results can quickly reflect the immediate pressure impact of recent continuous high-rate discharge behavior on the battery. When n is a larger value, it can smooth historical discharge data to a certain extent and reduce the fluctuation impact of a single abnormal discharge behavior on the overall evaluation results. The value of n can be dynamically adjusted according to the application scenario of the target battery. For example, for consumer electronics batteries, due to their high discharge frequency and rapid load changes, the most recent 3-5 discharge behaviors can be selected to enhance the model's sensitivity to short-term high-rate discharge, thereby more timely identifying instantaneous thermal stress risks. For batteries used in energy storage systems or power tools, since their discharge process is relatively stable and has a long cycle, the most recent 2-3 discharge behaviors can be selected to reduce computational complexity and balance real-time performance and model stability.

[0081] In step S214, the formula for calculating the time decay weight is as follows:

[0082] ,

[0083] In the formula, D pressure The discharge pressure parameter is represented by β, and the discharge attenuation coefficient is represented by D. i t represents the discharge rate of the i-th discharge behavior in the most recent n discharges. i This represents the time interval between the most recent nth and ith discharge events and the current time.

[0084] In a preferred embodiment, n is set to 3, the charging attenuation coefficient α is set to 0.98, and the discharging attenuation coefficient β is set to 0.97. In actual battery operation, the impact mechanisms of high-rate discharge and high-rate charging on battery health differ significantly. High-rate loads during discharge often cause large current surges and thermal stresses in a short period, with damage characteristics tending towards transient, irreversible, and structural destruction, including active material shedding, rapid electrode temperature rise, and localized electrolyte decomposition. Therefore, to more accurately reflect the immediate impact and acute stress characteristics of discharge behavior, this embodiment uses a faster attenuation coefficient for discharge behavior, i.e., β is set to 0.97, allowing its historical impact to decay more rapidly over time, thus highlighting the contribution of recent discharge behavior to the current stress state. In contrast, high-rate charging is more likely to induce slow-accumulating chemical and structural degradation, such as SEI film thickening, increased polarization, and increased ion migration resistance, with effects exhibiting a certain degree of lag and cumulativeity. Based on this, the charging attenuation coefficient is set to a relatively gradual attenuation coefficient, i.e., α is set to 0.98, in order to retain more weight of historical charging behavior in the pressure calculation, thereby reflecting the long-term stress accumulation effect of the charging process. At the same time, setting the number of recent charging and discharging behaviors, n, to 3 can ensure the sensitivity of the calculation model while avoiding the increase in computational complexity or the lag in response to short-term states caused by introducing too much historical data.

[0085] In the solution of this invention embodiment, by introducing the time decay mechanism, it is possible to effectively distinguish the different pressure accumulation effects brought about by short-term continuous high-rate charging and discharging and dispersed charging and discharging modes without increasing computational complexity, so that the charging and discharging pressure parameters can more realistically reflect the instantaneous load pressure and thermal stress level of the target battery.

[0086] In some embodiments, the basic characteristic parameters may also include temperature and pressure parameters.

[0087] Figure 5 A schematic flowchart illustrating a method for calculating temperature and pressure parameters according to an embodiment of the present invention is shown. Figure 5 As shown, the calculation method for these temperature and pressure parameters includes:

[0088] Step S215: Determine the current average temperature T based on the temperature parameters of the current charging process. avg ;

[0089] Step S216, based on the current average temperature T avg The temperature and pressure parameters T are determined using the following formula. pressure ,

[0090] ;

[0091] Among them, a1, a2, a3, b1, b2, c1, c2 and c3 are all constants, satisfying a1 < a2 < a3, and c1, c2 and c3 are all greater than 0. b1 and b2 represent the initial pressure coefficients corresponding to the temperature intervals.

[0092] In a preferred embodiment, a1, a2 and a3 can be respectively taken as 10°C, 25°C and 40°C. b1 and b2 can take any value between 0 and 1, for example, they can be 0.8 and 0.2. The constants c1, c2 and c3 can take the values 0.03, 0.01 and 0.02. When the current average temperature is between a1 and a2, it indicates that the target battery is in a relatively ideal thermal equilibrium state. At this time, a smaller temperature change coefficient c2, such as 0.01, is selected to characterize the stable charging state of the battery under normal temperature conditions. When the current average temperature is higher than a2, it indicates that the target battery may be in a high-temperature stress environment. At this time, a larger temperature change coefficient c3, such as 0.02, is selected. When the current average temperature is less than a1, it indicates that the target battery is in a low-temperature working state, the electrochemical reaction rate is significantly reduced, and there are immediate risks such as lithium deposition and increased polarization. To improve the response sensitivity of the model to low-temperature charging risks, a larger temperature change coefficient c1, such as 0.03, is selected at this time. Through the above settings, the charging control parameters can be adjusted in time when the temperature deviates from the normal range, so as to prevent the battery performance decay or safety hazards caused by abnormal temperature charging.

[0093] In some embodiments, the basic characteristic parameter may further include a cycle number pressure parameter.

[0094] The cycle number pressure parameter N pressure The calculation formula is:

[0095] ;

[0096] In the formula, N c represents the cumulative charge-discharge cycle number, k1 and k2 are both constants representing the cycle number penalty coefficient, is the preset cycle interval value, and k1, k2 and are all positive numbers, represents taking the integer part of the division result of the cumulative cycle number and the preset cycle interval , represents the modulus result of the cumulative cycle number with respect to the preset cycle interval.

[0097] In the above formula, the constant k1 represents the stepwise pressure increase corresponding to the degradation of the battery's basic performance after each complete cycle, such as 100 charge-discharge cycles. The constant k2 represents the slight additional pressure change resulting from the gradual increase in the number of cycles within a stage. Since the quantified result obtained by rounding is used to characterize the cumulative effect of the cycle in each stage, its influence on the pressure parameter is significantly greater than the slight changes within the stage reflected by the modulo calculation. Therefore, the value of k1 is significantly greater than that of k2. The constants k1 and k2 are any values ​​between 0 and 1. In a preferred embodiment, k1 and k2 are 0.05 and 0.0002, respectively. The preset cycle interval value ∆N is used to determine the time scale for updating the penalty term while balancing calculation accuracy and real-time performance. ∆N can be, for example, 100.

[0098] In step S22, the adjustment coefficient refers to the tolerance level reflecting the impact of battery health status on overall load-bearing capacity, dynamically calculated based on the battery health status (SOH). The adjustment coefficient proportionally controls the baseline pressure value in battery pressure assessment to reflect the regulating effect of battery aging on the withstand pressure. This adjustment coefficient reflects the changing pattern of battery withstand pressure capacity at different health stages. When SOH is at a high level, it indicates that the target battery is in a healthy state and has strong tolerance to charge and discharge pressures; the adjustment coefficient is relatively small to maintain the original assessment result of the baseline pressure value. When SOH drops below the threshold, it indicates that the battery has entered the degradation stage, and its withstand pressure decreases significantly. At this time, the adjustment coefficient automatically increases to amplify the baseline pressure value, thereby enhancing the risk sensitivity of aging batteries in pressure assessment.

[0099] In one embodiment, the formula for calculating the adjustment factor is:

[0100] ;

[0101] Among them, K dyn This represents the adjustment factor, and k3 is the aging tolerance factor.

[0102] The aging tolerance coefficient k3 can be any value between 0.8 and 1.2, for example, it can be 0.8, 1, or 1.2. When the value of k3 is too large, the amplification effect of the system on the impact of battery aging will be significantly enhanced, causing the base pressure value to be excessively amplified. This may cause the control system to enter the current-limiting charging mode prematurely, resulting in over-protection. Conversely, when the value of k3 is too small, the system's sensitivity to the degree of battery aging decreases, and insufficient protection may occur.

[0103] In step S23, one embodiment of the method for calculating the target battery baseline pressure value is as follows:

[0104]

[0105] Among them, b trs C represents the baseline pressure value. pressure D represents the charging pressure parameter. pressure T represents the discharge pressure parameter. pressure N represents temperature and pressure parameters. pressure K represents the pressure parameter indicating the number of cycles. dyn The numbers represent adjustment coefficients, and w1, w2, w3, and w4 are the weighting coefficients for each item.

[0106] Each fundamental characteristic parameter is assigned a different weight coefficient when calculating the base pressure value to reflect the degree of influence of different parameters on the overall battery pressure state. The weight coefficient for charging behavior is lower than that for discharging behavior because discharging behavior has higher uncertainty and instantaneous impact compared to charging behavior, and its influence on the battery's internal thermal stress and chemical stability is more significant. To ensure the safety margin of the pressure assessment model, the discharging weight coefficient is relatively high to highlight the dominant role of the discharging process in the overall pressure assessment. The weight coefficient for temperature parameters is relatively low. This is because within the normal operating temperature range of the battery, temperature changes are usually slow and controllable, and their impact on the instantaneous pressure within a single charging cycle is relatively small. Furthermore, temperature changes often exhibit seasonal or environmental patterns; therefore, a lower weight is used in the model to avoid over-amplifying its influence. The weight coefficient for cycle number parameters is relatively high. Since increasing the number of cycles directly leads to battery capacity decay, increased internal resistance, and reduced reversible reaction activity, its impact on long-term battery performance degradation is cumulative and irreversible. Therefore, a higher weight is given in the pressure assessment model to strengthen its influence in long-term health prediction. In one embodiment, w1, w2, w3, and w4 are any values ​​from 0 to 1.5, for example, 0.5, 0.7, 0.12, and 1, respectively.

[0107] In step S2, the correction index value may include a first penalty value used to impose constraints on continuous fast charging behavior. The calculation method of the first penalty value includes the following steps: obtaining the target charging rate and the corresponding time interval of the target battery's most recent m charging behaviors; when the target charging rate is greater than or equal to a first preset charging rate threshold and the corresponding time interval is less than a first preset time threshold, the continuous fast charging behavior penalty value is set to a first preset positive value; when there is at least one standard charging behavior or idle behavior between two adjacent charging behaviors in the m charging behaviors, the continuous fast charging behavior penalty value is set to zero; otherwise, the continuous fast charging behavior penalty value is set to a preset negative value.

[0108] Specifically, if in the target battery's most recent m charging events there is a charging rate greater than or equal to a first preset charging rate threshold and the time interval between two adjacent charging events is less than a first preset time threshold, it indicates that the battery is in a high-frequency fast charging state, the internal temperature has not fully cooled down, and the electrode material structure has not fully recovered. In this case, a positive penalty value is assigned to increase the pressure penalty. If there is a standard charging or resting period between two adjacent fast charging events, it is considered that the battery has gained sufficient recovery time, and the first penalty value is set to zero to cancel the continuous penalty. When there is no fast charging for a long time, a preset negative value can be assigned as compensation to reflect the positive impact of recovery operation on battery health.

[0109] The first preset charging rate threshold is determined based on the battery's allowable standard fast charging rate, for example, a value of 1.0C. The first preset time threshold is determined based on the battery's natural recovery time, for example, a value of 24 hours. The first preset positive value is any value between 0.1 and 0.15, for example, a value of 0.12. The cumulative first preset positive value does not exceed 0.24 to prevent excessive penalty. The preset negative value is any value between -0.07 and -0.05, for example, a value of -0.06, to reflect the positive contribution of conservative use to battery health.

[0110] In some embodiments, the correction index value may further include a second penalty value for imposing constraints on charge-discharge coupling behavior. The calculation method for the second penalty value includes the following steps: obtaining the charging rate of the current charging behavior, the discharge rate of the most recent complete discharge behavior, and the time interval between the two behaviors; when the most recent discharge rate is greater than or equal to a preset discharge rate threshold, the current charging rate is greater than or equal to a second preset charging rate threshold, and the time interval is less than or equal to a second preset time threshold, the charge-discharge coupling penalty value is set to a second preset positive value; otherwise, the charge-discharge coupling penalty value is set to zero.

[0111] Specifically, if the most recent discharge rate is greater than or equal to a preset discharge rate threshold, the current charging rate is greater than or equal to a second preset charging rate threshold, and the time interval between the two actions is less than or equal to a second preset time threshold, the combination of actions is determined to have the risk characteristic of immediate fast charging after a high-rate discharge. In this case, the charge-discharge coupling penalty value is set to a second preset positive value to increase the pressure penalty value. If the discharge rate is low, the charging rate is within a safe range, or the time interval between the two actions is sufficient, then it is considered that there is no risk characteristic of immediate fast charging after a high-rate discharge, and the second penalty value is set to zero.

[0112] The first preset discharge rate threshold is based on the battery's high-rate discharge, for example, a value of 2.0C, requiring a discharge time of at least 2 minutes. The second preset charging rate threshold is based on the battery's fast-charging rate, for example, a value of 1.0C, requiring a charging time of at least 2 minutes. The second preset time threshold is based on the minimum cooling or recovery interval between battery discharge and charging, for example, a value of 3 hours. The second preset positive value is any value between 0.12 and 0.24, for example, a value of 0.18. The cumulative second preset positive value does not exceed 0.36 to prevent excessive penalty.

[0113] In some embodiments, the correction index value may further include a first compensation value for rewarding the cooling behavior of the target battery. The calculation method for the first compensation value includes the following steps: obtaining the time interval between the most recent discharge behavior and the current charging behavior; if the time interval is greater than or equal to the required cooling period of the battery, multiplying the sum of the first penalty value and the second penalty value by a cooling coefficient and assigning it to the first compensation value; otherwise, setting the first compensation value to zero. It is understood that when the interval is greater than or equal to the required cooling period of the battery, it is determined that the battery has completed the natural cooling and stress release process. At this time, multiplying the sum of the first penalty value and the second penalty value by the cooling coefficient and assigning it to the first compensation value can reflect the positive effect of the cooling behavior on battery pressure recovery, thereby reducing the parameters calculated in the penalty term and the battery pressure index.

[0114] The required cooling period for the battery defines the standard time needed for the battery to recover from a high-stress state to a stable state. This required cooling period can be any value between 48h and 72h, for example, 72h. This value represents a time threshold that achieves an optimal balance between electrochemical recovery efficiency, user behavior patterns, thermal management capabilities, and algorithm feasibility under current technological conditions. The cooling coefficient is negative and can take any value between -0.6 and -0.4, for example, -0.5.

[0115] By employing the aforementioned calculation method for basic pressure values ​​and correction index values, the system can accurately identify battery pressure changes under different charging behavior modes, thereby improving the sensitivity and accuracy of pressure assessment.

[0116] In step S3, the formula for calculating the pressure index is:

[0117] ;

[0118] Wherein, BPI represents the battery stress index, b trs P represents the base pressure value. continuity P is the first penalty value used to impose constraints on continuous fast charging behavior. coupling P is the second penalty value that imposes constraints on the charge-discharge coupling behavior. resetThe first compensation value is used to reward the cooling behavior of the target battery.

[0119] Therefore, the calculation method of the Battery Pressure Index (BPI) not only comprehensively considers the basic pressure characteristics of the battery under normal operating conditions, but also introduces multiple correction index values ​​to dynamically correct abnormal charging and discharging behavior, time interval characteristics, and static recovery state, thereby more accurately reflecting the pressure level of the battery in real-world usage scenarios.

[0120] In step S4, the preset threshold is not a fixed constant, but is dynamically determined based on the current state of health (SOH) of the target battery. The method for adjusting this preset threshold is as follows:

[0121] When the health status of the target battery is greater than the first health status threshold, the preset threshold is determined to be any value between 2.4 and 2.6, where the first health status threshold is any value between 85% and 95%, for example, 90%.

[0122] When the target battery's health level is greater than or equal to the second health level threshold and less than or equal to the first health level threshold, the preset threshold is determined to be any value in 2.1-2.4, wherein the second health level threshold is any value in 75%-85%, for example, 80%;

[0123] When the target battery's health level is greater than or equal to the third health level threshold and less than or equal to the second health level threshold, a preset threshold is determined to be any value between 1.8 and 2.1, wherein the third health level threshold is any value between 65% and 75%, for example, 70%;

[0124] When the health status of the target battery is less than the third health status threshold, the preset threshold is determined to be any value between 1.5 and 1.8.

[0125] Different preset thresholds correspond to different charging strategies. In a specific embodiment, the mapping relationship between battery health, preset thresholds, and charging strategies is shown in Table 1 below:

[0126]

[0127] Table 1 above lists four charging strategies, ranked from highest to lowest: fast charging strategy, limited fast charging strategy, standard charging strategy, and forced silent mode charging strategy. The charging rates for these four strategies could be, for example, 1.2C, 0.8C, 0.6C, and 0.3C, respectively.

[0128] In one embodiment, when the current battery pressure index is less than or equal to a corresponding preset threshold, it indicates that the battery is in a safe operating range, and the system maintains the charging mode corresponding to that preset threshold to ensure charging efficiency. When the current battery pressure index is slightly higher than the preset threshold, it indicates that the battery is currently experiencing stress slightly exceeding its healthy level, and the system downgrades to the charging mode corresponding to the next lower preset threshold to extend battery life. When the current battery pressure index is significantly higher than the preset threshold, the battery is determined to be in a high-risk state, and the system immediately downgrades to the charging mode corresponding to an even lower threshold, thereby avoiding the risk of overcharging or overheating. The range of "slightly higher" is any value between 0% and 50%, for example, 10%. The range of "significantly higher" is 50% or higher, for example, 50%. This tiered charging strategy can automatically determine the optimal charging mode under different health conditions of the target battery, thereby maximizing user experience and battery life while ensuring safety.

[0129] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented using software and a general-purpose hardware platform, or of course, using hardware. Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory, or random access memory, etc.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

[0131] To facilitate understanding of the technical solution of the present invention, the following detailed description is provided in conjunction with specific embodiments.

[0132] This invention provides a charging control method, which includes:

[0133] Step 1: Obtain the operating parameters of the target battery.

[0134] In these operating parameters, the target battery's health is 85%, the average temperature during the current charging process is 38°C, the cumulative cycle count is 150, and the historical charge / discharge behavior and corresponding charge / discharge rates are:

[0135] At time T1, the battery is fast charging at a rate of 1.2C. This is the current time.

[0136] At time T2, the battery undergoes rapid discharge at a rate of 2.5C, which is 2 hours prior.

[0137] At time T3, the battery undergoes fast charging at a rate of 1.2C, which is 5 hours prior.

[0138] At time T4, the battery undergoes rapid discharge at a rate of 2.0C, which is 8 hours prior.

[0139] At time T5, the battery is fast-charging at a rate of 1.2C, which is 12 hours prior.

[0140] At time T6, the battery undergoes slow discharge at a rate of 0.5C, which is 24 hours prior.

[0141] Step 2: Calculate the base pressure value and correction index value based on the operating parameters of the target battery. The correction index value includes a first penalty value, a second penalty value, and a first compensation value.

[0142] Charging pressure parameters ;

[0143] Discharge pressure parameters ;

[0144] Temperature and pressure parameters ;

[0145] Cycle count pressure ;

[0146] Adjustment coefficient ;

[0147] Base pressure value ;

[0148] First penalty value Second penalty value First compensation value .

[0149] Step 3: Calculate the current pressure index of the target battery.

[0150] Current pressure index .

[0151] Step 4: Determine the preset threshold and charging strategy.

[0152] According to Table 1, the current health of the target battery is 85%, corresponding to a preset threshold of 2.4. The charging strategy is limited fast charging, with a charging rate of 0.8C. Since the current stress index (BPI) is 2.533, which is slightly higher than the preset threshold of 2.4, the charging strategy is downgraded by one level, i.e., it is determined to be a standard charging strategy, with a corresponding charging rate of 0.6C.

Claims

1. A charge control method characterized by, The method comprises the following steps: obtaining the operation parameters of the target battery, the operation parameters comprising the health degree of the target battery, the temperature parameter of the current charging process, the cumulative cycle number, the historical charging and discharging behavior and the corresponding charging and discharging rate; calculating the basic pressure value reflecting the pressure influence under the current operation condition of the target battery, at least one correction index value reflecting the additional pressure influence under the abnormal charging and discharging or standing condition and a plurality of basic characteristic parameters reflecting the pressure influence under the current operation condition of the target battery according to the operation parameters of the target battery; weighting and calculating the basic pressure value and the at least one correction index value to obtain the current pressure index of the target battery; comparing the current pressure index with a preset threshold value, and triggering the down-regulation control of the charging strategy when the current pressure index is greater than the preset threshold value, so as to reduce the charging rate or the charging power; the basic characteristic parameters comprise the charging pressure parameter and the discharging pressure parameter, and the calculation method of the charging pressure parameter and the discharging pressure parameter comprises the following steps: obtaining the attenuation coefficient corresponding to the charging and discharging type, the charging and discharging rate of the last n charging and discharging behaviors and the time interval between the last n charging and discharging behaviors and the current time, wherein n≥2; determining the corresponding charging pressure parameter and discharging pressure parameter based on the attenuation coefficient, the operation rate and the time interval according to a calculation method containing a time attenuation weight.

2. The charge control method according to claim 1, characterized by, the calculation method of the basic pressure value comprises the following steps: calculating an adjustment coefficient according to the health degree of the target battery; weighting and calculating the plurality of basic characteristic parameters, and multiplying the calculation result by the adjustment coefficient to obtain the basic pressure value of the target battery.

3. The charge control method according to claim 2, characterized by, the calculation method of the temperature pressure parameter comprises the following steps: determining a current average temperature T from temperature parameters of a current charging process avg ; According to the current average temperature T avg The temperature pressure parameter T is determined according to the following formula pressure , ， wherein a1, a2, a3, b1, b2, c1, c2 and c3 are constants, a1 4. The charge control method according to claim 3, characterized by, The basic characteristic parameter includes a cycle number pressure parameter, the cycle number pressure parameter N pressure The calculation formula is: ， Where, N c This represents the cumulative number of iterations, where k1 and k2 are both constants. The preset cycle interval value is defined, and k1, k2, and All are positive numbers. This indicates the cumulative number of iterations and the preset iteration interval. The result of division is the integer part. This represents the result of modulo the cumulative number of iterations with respect to the preset iteration interval.

5. The charge control method according to any one of claims 2 to 4, characterized by, the calculation formula of the adjustment coefficient is: ， wherein K dyn is an adjustment factor, k3 is an aging tolerance factor, and SOH is the state of health of the target battery.

6. The charge control method according to claim 5, characterized by, the correction index value comprises a first penalty value for imposing a constraint on continuous fast charging behavior, and the calculation method of the first penalty value comprises the following steps: obtaining the target charging rate of the last m charging behaviors of the target battery and the corresponding time interval; when the target charging rate is greater than or equal to a first preset charging rate threshold value and the corresponding time interval is less than a first preset time threshold value, the first penalty value is valued as a first preset positive value; when there is at least one standard charging behavior or standing behavior between the last m charging behaviors, the first penalty value is valued as zero; otherwise, the first penalty value is valued as a preset negative value.

7. The charge control method according to claim 6, characterized by, the correction index value comprises a second penalty value for imposing a constraint on the charging and discharging coupling behavior, and the calculation method of the second penalty value comprises the following steps: obtaining the charging rate of the current charging behavior, the discharging rate of the last complete discharging behavior and the time interval between the two behaviors; when the time interval is greater than or equal to a preset cooling time threshold, the first penalty value and the second penalty value are multiplied by a cooling coefficient and assigned to the first compensation value; otherwise, the first compensation value is zero.

8. The charge control method according to claim 7, characterized by, The correction index value includes a first compensation value for rewarding the cooling behavior of the target battery, and the calculation method of the first compensation value includes the following steps: obtaining the time interval between the last discharge behavior and the current charging behavior; when the time interval is greater than or equal to the required cooling time length of the battery, the sum of the first penalty value and the second penalty value is multiplied by a cooling coefficient and assigned to the first compensation value; otherwise, the first compensation value is zero.

9. The charge control method according to claim 8, characterized by, The preset threshold is adjusted according to the current health degree of the target battery.

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