A multi-node dynamic derating charging control method for aluminum batteries

Abstract

This invention discloses a multi-node dynamic derating charging control method for aluminum batteries, belonging to the field of charging control technology. It addresses the problem of increased risk of local overpolarization by constructing a multi-node charging state acquisition network to monitor multiple electrochemical response regions within the battery in real time. During charging, the node voltage and branch current of each monitoring node are collected, the voltage rise rate is calculated to form the polarization accumulation density, and the equivalent impedance of the node and its changing trend are obtained by combining superimposed ripple analysis. Reaction-limited characteristic parameters are constructed. When the reaction-limited characteristic of a certain monitoring node exceeds a preset threshold, the current allocation weight of the corresponding branch of that node is adaptively corrected, implementing fixed-point dynamic derating control. While maintaining the overall charging efficiency at a relatively stable level, this method effectively reduces the risk of local overpolarization and improves cycle stability and capacity retention under high-rate charging conditions.

Description

Technical Field

[0001] This invention relates to the field of charging control technology, and more specifically, to a multi-node dynamic derating charging control method for aluminum batteries. Background Technology

[0002] As a new type of rechargeable battery system, aluminum batteries have gradually gained attention in energy storage, electric vehicles and distributed power systems due to their advantages such as abundant aluminum resources, low cost and high theoretical specific capacity. Especially in high-rate charging scenarios, in order to meet the demand for rapid energy replenishment, constant current or staged constant current and constant voltage charging strategies are usually adopted, and the power management unit performs unified current regulation on the entire battery pack.

[0003] The existing technology has the following shortcomings:

[0004] Currently, existing technologies mainly rely on unified current-limiting control based on the terminal voltage, overall charging current, and temperature parameters of the entire battery pack. They lack the technical means for multi-node distributed monitoring and independent analysis of different electrochemical regions within the battery, making it difficult to identify local current density anomalies and polarization accumulation imbalances. During medium-to-high rate charging, when local areas experience abnormally high polarization voltages due to structural differences, the overall terminal voltage may still remain within a safe range, failing to trigger targeted control in a timely manner. This leads to increased risk of local over-polarization and decreased cycle stability. Conversely, implementing overall derating control reduces overall charging efficiency. Therefore, a multi-node dynamic derating charging control method for aluminum batteries is proposed.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] To overcome the aforementioned deficiencies in the prior art, embodiments of the present invention provide a multi-node dynamic derating charging control method for aluminum batteries. This method utilizes a multi-node distributed state sensing mechanism, a collaborative acquisition and analysis mechanism for node voltage and branch current, a polarization accumulation feature construction and node impedance change trend evaluation mechanism, and a branch current weight adaptive correction and fixed-point dynamic derating control mechanism based on response-limited characteristics to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a multi-node dynamic derating charging control method for aluminum batteries, comprising the following steps:

[0008] Step S1: After reshaping the aluminum battery region, multiple monitoring node locations are generated. Sensing units are deployed at each monitoring node location. During charging, the state of charge information of the aluminum battery is collected and it is determined whether the local polarization mode is triggered.

[0009] Step S2: In the local polarization mode, the node voltage of the monitoring node is collected by the sensing unit, the polarization accumulation density is calculated based on the node voltage, the monitoring node is subjected to superimposed ripple analysis processing and node impedance data is generated.

[0010] Step S3: Evaluate the impedance change trend of the monitoring nodes based on the node impedance data, generate the response limitation characteristics of the monitoring nodes by combining the polarization accumulation density, analyze the polarization imbalance state of the monitoring nodes based on the response limitation characteristics, and screen and mark the monitoring nodes.

[0011] Step S4: Collect the branch current of the marked monitoring node, access the weight allocation table to retrieve the current allocation weight of the marked monitoring node, and perform derating control on the marked monitoring node after correcting the current allocation weight using the response limitation feature.

[0012] In a preferred embodiment, in step S1, the aluminum battery is subjected to a regional reshaping process, which divides the interior of the aluminum battery into multiple electrochemical response zones, and selects the geometric center of each electrochemical response zone as the monitoring node location.

[0013] Sensing units are deployed at each monitoring node location. A sensing unit is a physical acquisition component deployed at each monitoring node location to realize in-situ acquisition of electrochemical state quantities and signal characterization conversion.

[0014] Aluminum batteries are secondary batteries that use aluminum or aluminum alloys as the negative electrode active material, graphite-like materials, transition metal oxides or organic compounds as the positive electrode active material, and ionic liquids or deep eutectic solvents containing aluminum complex ions as electrolytes. They achieve energy storage and release through the intercalation / deintercalation or deposition / dissolution reactions of aluminum ions.

[0015] Regional reshaping refers to the equivalent partitioning and modeling of electrochemically active regions based on the physical structural parameters of the internal electrodes and the distribution of current confluence paths in aluminum batteries.

[0016] In a preferred embodiment, in step S1, when the aluminum battery is in a charging state, the state of charge information of the aluminum battery is obtained by collecting the total charging current and rated capacity of the aluminum battery and using the ampere-hour integration method.

[0017] The charging rate of the aluminum battery is calculated by dividing the total charging current of the aluminum battery by its rated capacity.

[0018] When the state of charge falls within the preset polarization range and the charging rate is greater than or equal to the preset charging threshold, it is determined that the local polarization mode is triggered.

[0019] Otherwise, it is determined that the local polarization mode is not triggered.

[0020] In a preferred embodiment, in step S2, after the local polarization mode is triggered, the node voltage of each monitoring node is collected in real time using the sensing unit.

[0021] The node voltage is the instantaneous potential difference between the monitoring node and the negative terminal reference of the battery;

[0022] Under constant current charging conditions, the node voltage rise rate is calculated by time differentiation of the node voltage. The node voltage rise rate is the rate of increase of polarization voltage per unit time.

[0023] The average node voltage rise rate is obtained by calculating the average node voltage rise rate within a preset time window. At the same time, the average voltage rise rate of all monitored nodes is calculated. The node polarization offset is obtained by subtracting the average node voltage rise rate from the average node voltage rise rate.

[0024] The polarization cumulative density is defined as the result of the time integral of the absolute value of the node polarization offset within a preset time window.

[0025] In a preferred embodiment, in step S2, the monitoring node is subjected to superimposed ripple analysis processing to obtain the current disturbance amplitude at different frequencies; the superimposed ripple originates from the periodic current disturbance generated by the modulation of the charging power switch, and the current disturbance is obtained by extracting the components of the total charging current;

[0026] The node voltage is decomposed in the frequency domain to extract the voltage component amplitude corresponding to the current disturbance frequency. Under the condition of amplitude approximation, the node equivalent impedance is defined as the ratio of the voltage component amplitude to the current disturbance amplitude at the same frequency.

[0027] The node impedance data is obtained by calculating the average value of the equivalent impedance of the nodes within a preset time window.

[0028] In a preferred embodiment, in step S3, the node impedance data are arranged in chronological order, and the difference between the node impedance data at the end sampling time and the node impedance data at the beginning sampling time is calculated to obtain the net impedance change.

[0029] The impedance difference is obtained by subtracting the impedance data of adjacent nodes and taking the absolute value. The average impedance is obtained by averaging the impedance differences.

[0030] The ratio of the net change in impedance to the average impedance is used as the trend of impedance change.

[0031] The impedance variation trend and polarization accumulation density are standardized to obtain the impedance variation coefficient and polarization accumulation coefficient, respectively.

[0032] The response-limited characteristics are calculated based on the impedance change coefficient and the polarization accumulation coefficient.

[0033] In a preferred embodiment, in step S3, the reaction-limited characteristics are compared with a preset reaction-limited threshold to analyze the polarization imbalance state of the monitoring node:

[0034] If the response limitation characteristic is greater than the preset response limitation threshold, the polarization imbalance state of the monitoring node is determined to be the response limitation enhancement state.

[0035] Conversely, the polarization imbalance state of the monitoring node is determined to be a limited and controllable state.

[0036] Monitoring nodes in a polarization imbalance state that is a reaction-limited enhanced state are marked.

[0037] In a preferred embodiment, in step S4, the branch current of the marked monitoring node is collected by the Hall current sensor, and the current allocation weight of the marked monitoring node is retrieved by accessing the weight allocation table.

[0038] The ratio of the reaction-limited feature to the preset reaction-limited threshold is calculated to obtain the limitation deviation coefficient;

[0039] The ratio of the preset derating sensitivity factor to the restricted deviation coefficient is used as the weight correction factor, and the current allocation weight is corrected using the weight correction factor.

[0040] The product of the weight correction factor and the current allocation weight is used as the corrected current allocation weight.

[0041] In a preferred embodiment, in step S4, the derating control process of the marked monitoring node is performed based on the corrected current allocation weight. Specifically, the current total charging current is obtained from the current setting message, and the product of the corrected current allocation weight and the current total charging current is used as the target derating current value corresponding to the marked monitoring node.

[0042] The branch current of the marked monitoring node is updated based on the target derating current value.

[0043] The technical effects and advantages of this invention are as follows:

[0044] This invention constructs a multi-node charging state acquisition network to monitor multiple electrochemical response regions within the battery in real time. During charging, the node voltage and branch current of each monitoring node are collected, the voltage rise rate is calculated to form the polarization accumulation density, and the equivalent impedance of the node and its changing trend are obtained by combining superimposed ripple analysis, thus constructing reaction-limited characteristic parameters. When the reaction-limited characteristic of a certain monitoring node exceeds a preset threshold, the current allocation weight of the corresponding branch of that node is adaptively corrected, implementing fixed-point dynamic derating control. This achieves accurate identification and targeted suppression of local polarization imbalances within the aluminum battery, effectively reducing the risk of local over-polarization while maintaining overall charging efficiency stability, and improving cycle stability and capacity retention under high-rate charging conditions. Attached Figure Description

[0045] Figure 1 This is a flowchart illustrating the implementation of a multi-node dynamic derating charging control method for aluminum batteries according to the present invention.

[0046] Figure 2 This is a schematic diagram illustrating the steps of a multi-node dynamic derating charging control method for aluminum batteries according to the present invention. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] This invention constructs a multi-node charging state acquisition network to monitor multiple electrochemical response regions within the battery in real time. During charging, the node voltage and branch current of each monitoring node are collected, the voltage rise rate is calculated to form the polarization accumulation density, and the equivalent impedance of the node and its changing trend are obtained by combining the superimposed ripple analysis, thus constructing reaction-limited characteristic parameters. When the reaction-limited characteristics of a certain monitoring node exceed a preset threshold, the current allocation weight of the corresponding branch of that node is adaptively corrected, implementing fixed-point dynamic derating control. This achieves accurate identification and targeted suppression of local polarization imbalances within the aluminum battery, effectively reducing the risk of local over-polarization while maintaining the overall charging efficiency at a relatively stable level.

[0049] Example 1, such as Figures 1 to 2 As shown, a multi-node dynamic derating charging control method for aluminum batteries includes the following steps:

[0050] Step S1: After reshaping the aluminum battery region, multiple monitoring node locations are generated. Sensing units are deployed at each monitoring node location. During charging, the state of charge information of the aluminum battery is collected and it is determined whether the local polarization mode is triggered.

[0051] Step S2: In the local polarization mode, the node voltage of the monitoring node is collected by the sensing unit, the polarization accumulation density is calculated based on the node voltage, the monitoring node is subjected to superimposed ripple analysis processing and node impedance data is generated.

[0052] Step S3: Evaluate the impedance change trend of the monitoring nodes based on the node impedance data, generate the response limitation characteristics of the monitoring nodes by combining the polarization accumulation density, analyze the polarization imbalance state of the monitoring nodes based on the response limitation characteristics, and screen and mark the monitoring nodes.

[0053] Step S4: Collect the branch current of the marked monitoring node, access the weight allocation table to retrieve the current allocation weight of the marked monitoring node, and perform derating control on the marked monitoring node after correcting the current allocation weight using the response limitation feature.

[0054] The specific implementation is as follows:

[0055] In step S1, the aluminum battery undergoes a regional reshaping process. Regional reshaping refers to the equivalent partitioning and modeling of the electrochemical active region based on the physical structural parameters of the internal electrodes and the distribution of current confluence paths.

[0056] It should be noted that an aluminum battery is a secondary battery that uses aluminum or aluminum alloy as the negative electrode active material, graphite-based materials, transition metal oxides or organic compounds as the positive electrode active material, and an ionic liquid or deep eutectic solvent containing aluminum complex ions as the electrolyte. It stores and releases electrical energy through the intercalation / deintercalation or deposition / dissolution reaction of aluminum ions.

[0057] Specifically, the electrode thickness distribution data and the equivalent resistance distribution data of the current collection path between the positive and negative current collectors of the aluminum battery are obtained. The electrode thickness distribution data is characterized by the thickness value of the electrode at the corresponding spatial coordinates, reflecting the mass distribution of active material per unit area. The larger the value, the higher the local electrochemical reaction capacity potential. The equivalent resistance distribution data of the current collection path is characterized by the equivalent current collection resistance from the corresponding position to the external terminal, reflecting the ease of current transmission. The larger the value, the higher the degree of current transport restriction at the corresponding position.

[0058] A comprehensive zoning index is constructed based on electrode thickness distribution data and equivalent resistance distribution data of current collection path:

[0059] ;

[0060] in, To comprehensively assess the quality of the zones, This is data on electrode thickness distribution. This is the data on the equivalent resistance distribution of the current collection path. This represents the average value of the electrode thickness distribution data. This represents the average value of the equivalent resistance distribution data for the current collection path. and These are the preset weighting coefficients.

[0061] The comprehensive zoning index is used to quantify the degree of local structural imbalance. The larger the absolute value, the more significant the difference between the corresponding location and the overall average structure.

[0062] Clustering is performed based on the numerical range of the comprehensive zoning index, dividing the aluminum battery into multiple electrochemical response zones, and selecting the geometric center of each electrochemical response zone as the monitoring node location.

[0063] Sensing units are deployed at each monitoring node location. A sensing unit is a physical acquisition component deployed at each monitoring node location to realize in-situ acquisition of electrochemical state quantities and signal characterization conversion.

[0064] When the aluminum battery is in the charging state, the state of charge (SOC) information of the aluminum battery is obtained by collecting the total charging current and rated capacity. The SOC is calculated using the ampere-hour integration method.

[0065] ;

[0066] in, for State of charge at time t, for State of charge at time t, For rated capacity, This represents the total charging current of the aluminum battery. and All are time index values. This is the start time.

[0067] The state of charge reflects the proportion of the current remaining capacity to the rated capacity. The higher the value, the closer the battery is to being fully charged, and the higher the risk of electrode polarization.

[0068] Meanwhile, the charging rate of the aluminum battery is calculated by dividing the total charging current of the aluminum battery by the rated capacity. The charging rate reflects the charging current intensity corresponding to a unit capacity. The larger the value, the more charge is input per unit time and the faster the polarization accumulation rate.

[0069] Triggering determination based on combined state of charge and charging rate:

[0070] When the state of charge falls into the preset polarization range and the charging rate is greater than or equal to the preset charging threshold, it indicates that the state of charge is in the sensitive range, the electrode reaction is gradually restricted and the current density is at a high level, the risk of local polarization increases significantly, and the local polarization mode is triggered.

[0071] Otherwise, it is determined that the local polarization mode is not triggered.

[0072] It should be noted that the preset polarization range refers to the capacity ratio range in which the state of charge of the aluminum battery is gradually limited by the interfacial reaction kinetics and the polarization voltage increase is significantly increased during the charging process. It is obtained through experimental calibration: under different state of charge conditions, a constant rate of charging is applied, and the polarization voltage increment per unit capacity is collected. When the polarization voltage increment shows a sustained proportional jump relative to the average value of the low SOC segment (e.g., exceeding a certain multiple of the benchmark average value), the corresponding state of charge lower limit is defined as the lower limit of the range; the inflection point where the risk of side reactions increases significantly is defined as the upper limit of the range. The preset charging threshold refers to the critical rate value for judging high current density charging conditions. It is defined as the minimum rate at which the current density per unit capacity reaches a level of significant polarization acceleration. It is determined through rate scanning experiments: the polarization impedance increment is measured at different charging rates. When the polarization impedance increment increases to a certain value, and the impedance growth rate per unit time is significantly higher than the low rate benchmark value (e.g., exceeding a certain multiple of the benchmark), this rate is defined as the preset charging threshold.

[0073] In step S2, after triggering the local polarization mode, the sampling mechanism of each monitoring node is activated, and the node voltage of each monitoring node is collected in real time using the sensing unit. The node voltage is the instantaneous potential difference between the monitoring node and the negative electrode reference terminal of the battery, reflecting the potential state of the corresponding electrochemical zone. An increase in its value corresponds to an increase in the cumulative polarization voltage.

[0074] Under constant current charging conditions, the node voltage rise rate is calculated by time differentiation of the node voltage. The node voltage rise rate reflects the rate of increase of polarization voltage per unit time. The larger the value, the faster the polarization accumulation of the corresponding monitoring node.

[0075] To eliminate the impact of instantaneous fluctuations, the average node voltage rise rate is calculated within a preset time window to obtain the average node voltage rise rate. At the same time, the average voltage rise rate of all monitored nodes is calculated. The node polarization offset is obtained by subtracting the average node voltage rise rate from the average node voltage rise rate. The node polarization offset reflects the degree of deviation of the node from the overall average polarization rate. The larger the absolute value, the more significant the difference between the node polarization behavior and the overall state.

[0076] Based on this, the polarization cumulative density is defined as the result of time integration of the absolute value of the node polarization offset within a preset time window. The polarization cumulative density reflects the cumulative degree of polarization deviation of the monitored node per unit time. The larger the value, the more likely the corresponding monitored node has a continuous polarization enhancement trend within the current time window.

[0077] After calculating the polarization accumulation density, the monitoring nodes were subjected to superimposed ripple analysis to obtain the amplitude of current disturbances at different frequencies. The superimposed ripples originated from the periodic current disturbances generated by the charging power supply switch modulation, and the current disturbances were obtained by extracting components from the total charging current.

[0078] Simultaneously, the node voltage is decomposed in the frequency domain to extract the voltage component amplitude corresponding to the current disturbance frequency.

[0079] Under the amplitude approximation condition, the node equivalent impedance is defined as the ratio of the voltage component amplitude to the current disturbance amplitude at the same frequency. The node equivalent impedance reflects the charge transport resistance of the electrochemical partition under small signal conditions. The larger the value, the higher the degree of restriction of the interface reaction.

[0080] The average value of the equivalent impedance of the node is calculated within a preset time window to obtain the node impedance data, which is used to characterize the electrochemical transport characteristics of the monitoring node in the current charging stage.

[0081] The above processing provides a quantifiable data basis for subsequent construction of response-limited features and determination of polarization imbalance through joint analysis of polarization accumulation density and node equivalent impedance.

[0082] In step S3, the node impedance data are arranged in chronological order, and the difference between the node impedance data at the end sampling time and the node impedance data at the beginning sampling time is calculated to obtain the net impedance change.

[0083] The impedance difference is obtained by subtracting the impedance data of adjacent nodes and taking the absolute value. The average impedance is obtained by averaging the impedance differences.

[0084] The ratio of the net change in impedance to the average impedance is used as the trend of impedance change. The larger the value, the more directional the impedance increase is, and the stronger the obstruction of the charge migration path.

[0085] The impedance variation trend and polarization accumulation density are standardized to obtain the impedance variation coefficient and polarization accumulation coefficient, respectively.

[0086] Calculation of response-limited characteristics based on impedance change coefficient and polarization accumulation coefficient: ,in, The impedance variation coefficient, This is the polarization cumulative coefficient. This is a characteristic of limited reactivity;

[0087] The greater the reaction restriction characteristics, the more obvious the degree of obstruction of electrochemical reaction kinetics inside the monitoring node, the more obvious the trend of local current distribution imbalance, and the higher the risk of polarization imbalance.

[0088] The polarization imbalance state of the monitoring nodes is analyzed by comparing the reaction-limited characteristics with the preset reaction-limited threshold.

[0089] If the response limitation characteristic is greater than the preset response limitation threshold, the polarization imbalance state of the monitoring node is determined to be the response limitation enhancement state.

[0090] Conversely, the polarization imbalance state of the monitoring node is determined to be a limited and controllable state.

[0091] When the polarization imbalance state is a state of enhanced response limitation, it indicates that the risk of local overpolarization is forming or continuing to intensify.

[0092] When the polarization imbalance state is a reaction-limited and controllable state, it indicates that a structural polarization imbalance has not yet formed.

[0093] Monitoring nodes in a polarization imbalance state that is a reaction-limited enhanced state are marked.

[0094] It should be noted that the standardization methods include, but are not limited to, standard linear transformation based on interval scaling, statistical Z-Score standardization method, or normalization method based on nonlinear mapping function. The application methods of standardization will not be elaborated here. The preset response limitation threshold can be set according to the statistical distribution of response limitation characteristics under healthy equilibrium state.

[0095] By setting a reaction-limited threshold, the risk of node polarization can be quickly and quantitatively identified. The node state is divided into two categories: enhanced and controllable. This ensures that subsequent derating control is only executed on nodes with real risks, avoiding overall current reduction and improving the control accuracy and efficiency of the high-rate charging process.

[0096] In step S4, the branch current of the marked monitoring node is collected by the Hall current sensor. The branch current refers to the charging current value in the charging branch corresponding to the marked monitoring node.

[0097] Access the weight allocation table to retrieve the current allocation weight of the marked monitoring node. The current allocation weight refers to the reference ratio coefficient of the branch current of each monitoring node to the total charging current under the condition that the aluminum battery is in a healthy equilibrium. The average ratio of the branch current to the total current can be calculated based on the data of the branch current and the total charging current as the initial current allocation weight. The current allocation weight is obtained after normalizing the ratio coefficients of all nodes.

[0098] The larger the current allocation weight, the higher the proportion of charging current borne by the branch corresponding to the marked monitoring node under normal conditions; the smaller the current allocation weight, the lower the proportion of charging current borne by the branch corresponding to the marked monitoring node under normal conditions.

[0099] Retrieve the response-limited characteristics of the marked monitoring nodes, and calculate the ratio between the response-limited characteristics and the preset response-limited threshold to obtain the limitation deviation coefficient;

[0100] Before performing derating control on the marked monitoring nodes, the ratio of the preset derating sensitivity factor to the restricted deviation coefficient is used as the weight correction coefficient, and the current allocation weight is corrected using the weight correction coefficient.

[0101] The product of the weight correction factor and the current allocation weight is used as the corrected current allocation weight.

[0102] Furthermore, based on the corrected current allocation weight, the derating control process is performed on the marked monitoring node. Specifically, the current total charging current is obtained from the current setting message, and the product of the corrected current allocation weight and the current total charging current is used as the target derating current value corresponding to the marked monitoring node.

[0103] The branch current of the marked monitoring node is updated based on the target derating current value.

[0104] It should be noted that the Hall current sensor is a magnetic field-inducing current detection device that achieves non-contact current measurement based on the Hall effect principle; the weight allocation table stores the current allocation weight parameters corresponding to each monitoring node in a healthy equilibrium state; the preset derating sensitivity factor is used to limit the adjustment intensity when the degree of reaction limitation deviation is mapped to the current reduction ratio, and can be set according to the aluminum battery's design capacity level, allowable temperature rise range, historical cycle decay data, or target life strategy; the current setting message is a current control command data frame generated and periodically sent by the charging controller according to a preset communication protocol, which can obtain the total charging current setting value of the aluminum battery.

[0105] By introducing a mapping relationship between the degree of restricted deviation and the derating sensitivity factor, the derating magnitude is dynamically matched with the risk level. This suppresses the risk of local overpolarization while maintaining the continuity of system control and the smoothness of regulation, thereby improving the safety and charging efficiency in a multi-node charging environment.

[0106] Finally, it should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0107] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0108] In this document, the singular forms “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that terms such as “comprising / including” or “having” specify the presence of the stated features, integrals, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integrals, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0109] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0110] The above description of the disclosed embodiments will enable those skilled in the art to make or use various modifications to these embodiments. It will be readily apparent to those skilled in the art that the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for controlling dynamic derating charging of aluminum batteries at multiple nodes, characterized in that: Includes the following steps: Step S1: After reshaping the aluminum battery region, multiple monitoring node locations are generated. Sensing units are deployed at each monitoring node location. During charging, the state of charge information of the aluminum battery is collected and it is determined whether the local polarization mode is triggered. Step S2: In the local polarization mode, the node voltage of the monitoring node is collected by the sensing unit, the polarization accumulation density is calculated based on the node voltage, the monitoring node is subjected to superimposed ripple analysis processing and node impedance data is generated. Step S3: Evaluate the impedance change trend of the monitoring nodes based on the node impedance data, generate the response limitation characteristics of the monitoring nodes by combining the polarization accumulation density, analyze the polarization imbalance state of the monitoring nodes based on the response limitation characteristics, and screen and mark the monitoring nodes. Step S4: Collect the branch current of the marked monitoring node, access the weight allocation table to retrieve the current allocation weight of the marked monitoring node, and perform derating control on the marked monitoring node after correcting the current allocation weight using the response limitation feature.

2. The method for controlling dynamic derating charging of an aluminum battery at multiple nodes according to claim 1, characterized in that: In step S1, the aluminum battery is subjected to regional reshaping treatment, dividing the interior of the aluminum battery into multiple electrochemical response zones, and selecting the geometric center of each electrochemical response zone as the monitoring node location. Sensing units are deployed at each monitoring node location. A sensing unit is a physical acquisition component deployed at each monitoring node location to realize in-situ acquisition of electrochemical state quantities and signal characterization conversion. Aluminum batteries are secondary batteries that use aluminum or aluminum alloys as the negative electrode active material, graphite-like materials, transition metal oxides or organic compounds as the positive electrode active material, and ionic liquids or deep eutectic solvents containing aluminum complex ions as electrolytes. They achieve energy storage and release through the intercalation / deintercalation or deposition / dissolution reactions of aluminum ions. Regional reshaping refers to the equivalent partitioning and modeling of electrochemically active regions based on the physical structural parameters of the internal electrodes and the distribution of current confluence paths in aluminum batteries.

3. The method for controlling dynamic derating charging of an aluminum battery at multiple nodes according to claim 1, characterized in that: In step S1, when the aluminum battery is in a charging state, the state of charge information of the aluminum battery is obtained by collecting the total charging current and rated capacity of the aluminum battery and using the ampere-hour integration method. The charging rate of the aluminum battery is calculated by dividing the total charging current of the aluminum battery by its rated capacity. When the state of charge falls within the preset polarization range and the charging rate is greater than or equal to the preset charging threshold, it is determined that the local polarization mode is triggered. Otherwise, it is determined that the local polarization mode is not triggered.

4. The method for controlling dynamic derating charging of an aluminum battery at multiple nodes according to claim 3, characterized in that: In step S2, after the local polarization mode is triggered, the node voltage of each monitoring node is collected in real time using the sensing unit. The node voltage is the instantaneous potential difference between the monitoring node and the negative terminal reference of the battery; Under constant current charging conditions, the node voltage rise rate is calculated by time differentiation of the node voltage. The node voltage rise rate is the rate of increase of polarization voltage per unit time. The average node voltage rise rate is obtained by calculating the average node voltage rise rate within a preset time window. At the same time, the average voltage rise rate of all monitored nodes is calculated. The node polarization offset is obtained by subtracting the average node voltage rise rate from the average node voltage rise rate. The polarization cumulative density is defined as the result of the time integral of the absolute value of the node polarization offset within a preset time window.

5. The method for multi-node dynamic derating charging control of aluminum batteries according to claim 4, characterized in that: In step S2, the monitoring nodes are subjected to superimposed ripple analysis processing to obtain the current disturbance amplitude at different frequencies; The superimposed ripple originates from the periodic current disturbance generated by the modulation of the charging power switch. The current disturbance is obtained by extracting the components of the total charging current. The node voltage is decomposed in the frequency domain to extract the voltage component amplitude corresponding to the current disturbance frequency. Under the condition of amplitude approximation, the node equivalent impedance is defined as the ratio of the voltage component amplitude to the current disturbance amplitude at the same frequency. The node impedance data is obtained by calculating the average value of the equivalent impedance of the nodes within a preset time window.

6. The method for controlling dynamic derating charging of an aluminum battery at multiple nodes according to claim 1, characterized in that: In step S3, the node impedance data are arranged in chronological order, and the difference between the node impedance data at the end sampling time and the node impedance data at the beginning sampling time is calculated to obtain the net impedance change. The impedance difference is obtained by subtracting the impedance data of adjacent nodes and taking the absolute value. The average impedance is obtained by averaging the impedance differences. The ratio of the net change in impedance to the average impedance is used as the trend of impedance change. The impedance variation trend and polarization accumulation density are standardized to obtain the impedance variation coefficient and polarization accumulation coefficient, respectively. The response-limited characteristics are calculated based on the impedance change coefficient and the polarization accumulation coefficient.

7. The method for multi-node dynamic derating charging control of aluminum batteries according to claim 1, characterized in that: In step S3, the reaction-limited characteristics are compared with a preset reaction-limited threshold to analyze the polarization imbalance state of the monitoring node: If the response limitation characteristic is greater than the preset response limitation threshold, the polarization imbalance state of the monitoring node is determined to be the response limitation enhancement state. Conversely, the polarization imbalance state of the monitoring node is determined to be a limited and controllable state. Monitoring nodes in a polarization imbalance state that is a reaction-limited enhanced state are marked.

8. The method for multi-node dynamic derating charging control of aluminum batteries according to claim 7, characterized in that: In step S4, the branch current of the marked monitoring node is collected by the Hall current sensor, and the current allocation weight of the marked monitoring node is retrieved by accessing the weight allocation table. The ratio of the reaction-limited feature to the preset reaction-limited threshold is calculated to obtain the limitation deviation coefficient; The ratio of the preset derating sensitivity factor to the restricted deviation coefficient is used as the weight correction factor, and the current allocation weight is corrected using the weight correction factor. The product of the weight correction factor and the current allocation weight is used as the corrected current allocation weight.

9. The method for controlling dynamic derating charging of an aluminum battery at multiple nodes according to claim 8, characterized in that: In step S4, the derating control process is performed on the marked monitoring node based on the corrected current allocation weight. Specifically, the current total charging current is obtained from the current setting message, and the product of the corrected current allocation weight and the current total charging current is used as the target derating current value corresponding to the marked monitoring node. The branch current of the marked monitoring node is updated based on the target derating current value.

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