Battery power limit estimation based on RC model

Abstract

A method for estimating the maximum power limit of a battery cell at a specified prediction time using an improved RC equivalent circuit battery model and based on the battery cell's state of charge (SOC), temperature, and state of health (SOH). The method includes determining peak and continuous current limits for the battery cell, predicting a peak voltage after a specified prediction time based on the peak current limit, determining a buffer value for the predicted peak voltage and the temperature of various battery components, setting a maximum current limit based on the buffer value, predicting a maximum voltage after a specified prediction time based on the maximum current limit, and determining a maximum power limit based on the predicted maximum voltage and maximum current limit.

Description

Background Art

[0001] The present disclosure relates to a battery power limit estimation method, wherein the method is based on an RC equivalent circuit model of a battery cell.

[0002] Lithium-ion batteries are used as energy sources for many electrical systems, particularly in hybrid electric vehicles (HEVs) and electric vehicles (EVs). In these vehicles, the batteries interact with other components through a battery management system (BMS) to provide power to the vehicle and meet the vehicle's energy needs while maintaining the safety of the electrical systems.

[0003] The reliability of these electrical systems is highly dependent on the health and safety of the batteries, so the BMS's ability to provide operational data that allows peak performance to be achieved without compromising the health and safety of the batteries is crucial. Without a fast and accurate battery model used by the BMS, it would be impossible to control and monitor the batteries installed in an HEV or EV. Lithium-ion battery models have been used to estimate battery metrics including state of charge (SOC), state of health (SOH), state of energy (SOE), and state of power (SOP). In addition, battery models are used to help the BMS implement functions such as battery control, real-time observation, parameter estimation, and battery optimization.

[0004] In all HEVs and EVs, the BMS needs to report the real-time power capacity of the battery pack to other vehicle systems, such as the hybrid control unit (HCU). The BMS uses the SOP to estimate the power capacity based on the battery current, SOC, temperature, and SOH. This accurate measurement of power capacity helps provide the required power to the HEV or EV based on the driver's demand or different environmental conditions, while ensuring that other systems do not overuse the battery and endanger their health and safety.

[0005] To accurately estimate the battery power capacity at the current time, the battery voltage and temperature after the specified prediction time should be predicted and considered. In addition, the temperatures of other battery modules and battery pack components should be considered to prevent these components and systems from reaching critical operating temperatures due to excessive power consumption or overcharging. Therefore, it is necessary to have a model to calculate these variables - especially under different SOC, battery temperature, and SOH conditions. However, all currently available BMSs use a simple structure that ignores these variables when determining power capacity. This leads to inaccurate power calculations, especially for aging batteries, batteries operating in low temperature conditions, and batteries with low SOC. Inaccurate power estimates can cause poor system performance or operation outside of safety parameters.

[0006] Traditional methods for calculating battery power capacity include the Partnership for Next Generation Vehicles (PNGV) Hybrid Pulse Power Characterization (HPPC) method. This method uses an internal resistance lookup table for different SOC and temperature values ​​to predict the battery cell voltage after a specified prediction time. However, this method does not consider the impact of the battery polarization level on the power calculation. Therefore, the traditional method is inaccurate in many cases, especially at low SOC and temperature. To solve this problem, an interactive estimation method based on an improved battery model is needed to calculate the battery polarization and take it into account in the voltage and peak power prediction process. Summary of the Invention

[0007] Disclosed herein is a method for predicting the maximum power that a battery pack can provide or receive at a given time by taking into account all battery limitations, including but not limited to minimum cell voltage, minimum cell voltage, maximum cell temperature, maximum module temperature, and maximum battery pack component temperature. In one embodiment, the method uses an RC model of a battery cell to predict the voltage of the battery cell at a specified time under different SOC, temperature, current, voltage, and SOH conditions. In one embodiment, the method uses a buffer function to take into account all of the battery limitations listed above for peak power calculations. In one embodiment, the method can be used by vehicles such as (but not limited to) electric vehicles, hybrid electric vehicles, and plug-in hybrid electric vehicles to calculate peak current and / or peak power on a battery pack installed in the vehicle.

[0008] Further disclosed herein is a system for estimating the maximum power limit of a battery cell at a specified predicted time, comprising a sensor system and a controller. In one embodiment, the sensor system is configured to receive a plurality of temperature measurements from a plurality of temperature sensors. In one embodiment, the controller is configured to receive data on a plurality of battery cell parameters and a plurality of temperature measurements from the sensor system. In one embodiment, the controller is configured to estimate the maximum power limit of the battery cell using a method such as the method described above.

[0009] In one embodiment, a method for estimating a maximum power limit of a battery cell includes determining a plurality of battery cell parameters; determining a peak current limit and a continuous current limit based on at least one of the plurality of battery cell parameters; determining a predicted peak voltage using an RC equivalent circuit model of the battery cell, wherein at least one of the plurality of RC equivalent circuit model parameters is set based on a specified prediction time, at least one of the plurality of battery cell parameters, and the peak current limit; determining a voltage buffer value based on the predicted peak voltage; determining a temperature buffer value based on a plurality of temperature measurements; determining a maximum current limit based on a weighting function applied to the peak current limit and the continuous current limit, wherein the weighting function value is determined based on the voltage buffer value and the temperature buffer value; determining a predicted maximum voltage based on the RC equivalent circuit model of the battery, wherein at least one of the plurality of RC equivalent circuit model parameters is set based on a specified prediction time, at least one of the plurality of battery cell parameters, and the peak current limit; determining the voltage buffer value based on the predicted peak voltage; and determining a maximum power limit based on the maximum current limit and the maximum voltage limit. In one embodiment, at least one of the plurality of parameters of the RC equivalent circuit model is set based on the specified prediction time, at least one of the plurality of battery cell parameters, and the maximum current limit.

[0010] In one embodiment, the plurality of battery cell parameters include at least one of a state of charge (SOC) of the battery cell, a temperature of the battery cell, and a state of health (SOH) of the battery cell.

[0011] In another disclosed embodiment, the maximum power limit is a maximum discharge power limit, the peak current limit is a peak discharge current limit, and the continuous current limit is a continuous discharge current limit. In another disclosed embodiment, the maximum power limit is a maximum charge power limit, the peak current limit is a peak charge current limit, and the continuous current limit is a continuous charge current limit.

[0012] In another disclosed embodiment, the battery cell is a battery cell included in a battery module, the battery module including at least one battery cell. In another disclosed embodiment, the battery module is a battery module included in a battery pack, the battery pack including at least one battery module.

[0013] In another disclosed embodiment, the plurality of temperature measurements includes at least one measurement from the group consisting of a maximum battery cell temperature, a maximum battery module temperature, and a maximum battery pack component temperature. In another disclosed embodiment, the plurality of temperature measurements includes a temperature of at least one device associated with the battery cell by proximity to the battery cell or by electrical connection to the battery cell.

[0014] In another disclosed embodiment, as part of determining the predicted peak voltage and the predicted maximum voltage, the RC equivalent circuit model performs a state of charge (SOC) calculation to predict the state of charge (SOC) after a specified prediction time has elapsed. In another disclosed embodiment, as part of determining the predicted peak voltage and the predicted maximum voltage, the RC equivalent circuit model performs a state of charge (SOC) calculation to estimate the state of charge (SOC) at an earlier time.

[0015] Other aspects, features, and techniques will be apparent to persons skilled in the relevant art(s) in view of the following detailed description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Features, objects, and advantages of the disclosed embodiments will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which like reference numerals designate corresponding references throughout, and in which:

[0017] Figure 1 is a perspective view of an exemplary embodiment of a vehicle including a battery pack for use in a power limit estimation method.

[0018] Figure 2 is a flow chart of an exemplary embodiment of a system for implementing a power limit estimation method.

[0019] Figure 3 is a block diagram of an exemplary embodiment of a power limit estimation method.

[0020] Figure 4 is a circuit diagram of an exemplary embodiment of a two-branch RC model equivalent circuit for a battery cell.

[0021] Figure 5 is a graphical representation of an exemplary embodiment of the relationship between a discharge voltage buffer function and a predicted voltage.

[0022] Figure 6 is a graphical representation of an exemplary embodiment of the relationship between a charge voltage buffer function and a predicted voltage.

[0023] Figure 7 is a graphical representation of an exemplary embodiment of a relationship between a temperature buffer function and the temperature of a battery component. DETAILED DESCRIPTION

[0024] One aspect of the present disclosure is directed to a power limit estimation method.

[0025] Reference throughout this document to "one embodiment," "some embodiments," "an embodiment," or similar terms means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of these phrases in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments without limitation. For example, two or more innovative methods described herein may be combined into a single method, but this application is not limited to the specific exemplary combinations of methods described herein.

[0026] As used herein, the term "a" shall mean one or more. The term "plurality" means two or more. The term "another" is defined as a second or more. The terms "including" and / or "having" are open-ended (e.g., comprising). As used herein, the term "or" shall be interpreted as inclusive or meaning any one or any combination. Thus, "A, B, or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B, and C." Exceptions to this definition occur only when a combination of elements, functions, steps, or acts are inherently mutually exclusive to some extent.

[0027] The character "N" is used hereafter to refer to the last member of a set or the total number of members in a set. The character "X" is used hereafter to refer to a variable member of a set. The characters "A," "B," "C," and so on, indicate specific but undefined members of a set.

[0028] Detailed descriptions of various embodiments are provided; however, it should be understood that the disclosed embodiments are merely exemplary and can be embodied in various alternative forms. The drawings are not necessarily drawn to scale; certain features may be exaggerated or minimized to show details of particular components. Therefore, the specific structural and functional details disclosed herein should not be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the disclosed embodiments.

[0029] Figure 1 is a perspective diagram of an exemplary embodiment of a vehicle 100 including a battery pack 210 for use in a method 300 for power limit estimation, where the power limit is a function of the continuous power that the battery pack 210 can provide at a given time and the peak power that the battery pack 210 can provide at a given time. Figure 1 The vehicle 100 shown is exemplary. The power limit estimation method 300 may be used with any vehicle that includes a battery pack or any other system for battery power limit estimation methods.

[0030] Figure 2is a flow chart of an exemplary embodiment of a system 200 for implementing a power limit estimation method 300. In one embodiment, the system 200 includes a battery pack 210, a controller 220, a sensor system 230, and a vehicle system 240, wherein the vehicle system 240 is connected to the battery pack 210 via a power conduit 245. In one embodiment, the system 200 receives data from other estimation systems, such as a state of charge (SOC) estimation system 250 and a state of health (SOH) estimation system 260.

[0031] In one embodiment, the battery pack 210 includes at least one battery module 212, and each of the at least one battery module 212 may also include at least one battery cell 215. In one embodiment, the power limit estimation method 300 is applied on a per-cell basis, providing a power limit estimate for each individual battery cell 215. In another embodiment, the power limit estimation method 300 is applied on a per-module basis. In another embodiment, the power limit estimation method 300 is applied to the battery pack 210 as a whole.

[0032] In one embodiment, the sensor system 230 includes a plurality of sensors, including but not limited to a battery temperature sensor 235 for each battery cell 215 in the battery pack 210, a module temperature sensor 232 for each battery module 212 in the battery pack 210, and a multifaceted temperature sensor 231 for any multifaceted component 211 in the battery pack 210. In one embodiment, the sensor system 230 transmits sensor data from the plurality of sensors to the controller 220, which then determines a battery power limit estimate based at least in part on the sensor data. In one embodiment, the controller 220 may further determine the battery power limit estimate based on a plurality of parameters provided by other estimation systems, such as a state of charge (SOC) estimation system 250 and a state of health (SOH) estimation system 260.

[0033] In another embodiment, the battery pack 210 releases power to the vehicle system 240 through the power conduit 245. In one embodiment, after the controller 220 determines the power limit estimate, the controller 220 sends instructions to the battery pack 210 to not provide more power to the vehicle system 240 than is allowed under the power limit. In another embodiment, after the controller 220 determines the power limit estimate, the controller 220 sends instructions to the vehicle system 240 to not draw more power from the battery pack 210 than is allowed under the power limit.

[0034] In another embodiment, battery pack 210 is charged using vehicle system 240 via power conduit 245. In this embodiment, vehicle system 240 may be a dedicated charging system, such as a solar panel grid or an AC charging system, such as an electric motor in regenerative braking mode. In one embodiment, after controller 220 determines the power limit estimate, controller 220 sends a command to battery pack 210 not to charge more than the power allowed by the power limit from vehicle system 240. In another embodiment, after controller 220 determines the power limit estimate, controller 220 sends a command to vehicle system 240 not to provide more power to battery pack 210 than the power allowed by the power limit.

[0035] Figure 3 is a block diagram of an exemplary embodiment of a power limit estimation method 300, wherein the power limit estimation method 300 is applied to a battery cell 215. In one embodiment, the power limit estimation method 300 includes a continuous current limit block 310, a peak current limit block 320, a capacity block 330, a peak voltage prediction block 340, a discharge / charge voltage buffer function block 350, a temperature buffer function block 360, a discharge / charge current capacity block 370, a maximum voltage prediction block 380, and a power capacity calculation block 390. In one embodiment, the power limit estimation method 300 estimates the power limit based on a plurality of battery cell parameters. In one embodiment, the plurality of battery cell parameters include the state of charge (SOC) of the battery cell 215, the temperature T of the battery cell 215, and the maximum voltage prediction block 380. cell and the state of health (SOH) of the battery cell 215 .

[0036] In one embodiment, the continuous current limit block 310 is based on the state of charge (SOC) of the battery cell 215, the temperature T cell and the state of health (SOH) of the battery cell 215 to determine the continuous discharge current limit I dischg,cont and continuous charge current limit I chg,cont In one embodiment, I dischg,cont and I chg,cont Contact acts as a safe operating limit for the battery cell 215 - as long as the charge and discharge currents into and out of the battery cell 215 remain below I dischg,cont and I chg,cont The battery cell 215 will operate safely.

[0037] In one embodiment, the peak current limit block 320 is based on the state of charge (SOC) of the battery cell 215, the temperature T cell and the state of health (SOH) of the battery cell 215 determine the peak discharge current limit I dischg,peak and peak charge current limit I chg,peakAs with the battery continuous current limit, all Li-ion battery manufacturers report the discharge peak current limit (I dischg,peak ) and charging peak limit (I chg,peak ). In one embodiment, the reported peak current limit is the current capacity of the battery cell 215 for different SOC and temperature values, assuming that the battery cell 215 is discharged or charged from a rest and open circuit voltage (i.e., the battery is not carrying a load). However, the manufacturer's reported peak current limit does not take into account alternate startup conditions, such as the possibility that a battery cell may be discharged shortly after a charge cycle. In addition, the reported peak current limit does not take into account design limitations at the battery module 212 or battery pack 210 level. In one embodiment, these oversights can be corrected by using improved current limits; the continuous current limit block 310 and / or the peak current limit block 320 can use an improved current limit estimation method.

[0038] In one embodiment, the capacity block 330 determines the capacity of the battery cell 215 based on the state of health (SOH) of the battery cell 215. In one embodiment, the capacity is defined as the available charge capacity of the battery cell 215 at 25° C., a 1C constant discharge rate, and a given SOH value, with the available charge capacity measured from a full charge to a minimum charge defined by a cutoff voltage.

[0039] In one embodiment, the peak voltage prediction block 340 predicts the battery voltage based on the discharge and charge peak current limits. In one embodiment, the predicted peak battery voltage is considered in the discharge / charge voltage buffer function 350. In one embodiment, the peak voltage prediction block 340 consists of two parts: SOC calculation and voltage prediction.

[0040] In order to predict the time t from the current time K To predict the battery voltage in seconds, it is necessary to estimate the K Seconds of application dischg,peak or I chg,peak The final SOC produced by discharging or charging the battery. In one embodiment, SOC dischg,final Defined as battery cell 215 in the battery cell with I dischg,peak The rate of discharge is specified for the predicted time t K The subsequent SOC value, SOC chg,final Defined as battery cell 215 in the battery cell with I chg,peak The rate of charge is specified for the predicted time t K In one embodiment, the final SOC prediction is calculated as follows:

[0041]

[0042]

[0043] Wherein, SOC0 is the SOC value of the battery cell 215 at the current time, and t K is the specified predicted time for the power limitation estimation method 300 to report the power capability. In one embodiment, t K Can vary depending on the control strategy used by the HCU. In one embodiment, if the SOC dischg,final Less than SOC min (For example, the battery cell 215 is expected to be K fully discharged during the period), the final SOC value will be set to SOC min And I dischg,peak will be recalculated as follows:

[0044]

[0045] Such that discharge at the reported discharge current limit does not discharge more from the battery cell 215 than is required to maintain the minimum SOC. In one embodiment, if the SOC chg,final Higher than SOC max (For example, the battery cell 215 is expected to be K fully charged during the period), the final SOC value will be set to SOC max And I chg,peak will be recalculated as follows:

[0046]

[0047] The reported charge current limits the charge to not charge the battery cell 215 more than allowed based on the maximum SOC. In one embodiment, the SOC is set based on the design parameters for the operation of the battery cell 215. min and SOC max .

[0048] In one embodiment, the SOC defined capacity value is updated based on the capacity determined by the capacity block 330. In one embodiment, the SOH value is estimated by an SOH block in the BMS.

[0049] In one embodiment, to calculate the power capacity, if the battery is dischg,peak or I chg,peak Discharging or charging, a battery model is needed to predict the battery voltage after the sampling period Δt. The model can be an imperial model or a physics-based model. In one embodiment, a two-branch RC model 400 (see Figure 4) to predict battery voltage and model battery polarization levels in response to various conditions. Figure 4 is a circuit diagram depicting an exemplary embodiment of an RC model 400 for use in the power limit estimation method 300. In one embodiment, all RC parameters (including but not limited to R0, C1, R1, C2, R2, and OCV) can be estimated by using a lookup table populated with data from tests performed on the battery cell 215. In one embodiment, R0 is determined as the state of charge (SOC) of the battery cell 215, the temperature T of the battery cell 215, and the power consumption of the battery cell 215. cell and the state of health (SOH) of the battery cell 215. In one embodiment, OCV is determined as the state of charge (SOC) of the battery cell 215, the temperature T cell and the state of health (SOH) of the battery cell 200. In one embodiment, C1, R1, C2, and R2 are determined as the state of charge (SOC) of the battery cell 215, the equivalent circuit current I, the temperature T of the battery cell 215, and the state of health (SOH) of the battery cell 200. cell and the state of health (SOH) of the battery cell 200. In one embodiment, the parameters of the RC model 400 are predicted by an unscented Kalman filter method.

[0050] In one embodiment, by using the RC model 400, the battery terminal voltage (V t ) can be calculated as follows:

[0051]

[0052] Where Δt is the incremental sampling period of the battery measurement value, k is the number of sampling steps, and K is the number of sampling steps taken (such that 1≤k≤K and KΔt=t K In one embodiment, in order to predict the battery voltage, it is assumed that at a specified prediction time t K Inner I dischg,peak or I chg,peak The equation is solved by performing a constant current discharge or charge at V. The initial values ​​of U1 and U2 are also required to solve the equation and should be estimated together with the battery SOC at the SOC block. In one embodiment, the initial values ​​of U1 and U2 are considered to be 0. In one embodiment, if the predicted discharge voltage is less than V min , or the predicted charging voltage is higher than V max , the battery peak current limit can be modified based on these minimum and maximum battery voltage limits.

[0053] In one embodiment, the discharge / charge buffer function block 350 defines a discharge voltage buffer value or a charge voltage buffer value based on the predicted battery voltage determined by the peak voltage prediction block 340, wherein the charge / discharge voltage buffer value is a weighted function representing a limit on the charge or discharge current capability of the battery cell 215. In one embodiment, the discharge / charge buffer function block 350 determines the discharge buffer value based on the battery peak discharge voltage value predicted by the peak voltage prediction block 340. The discharge buffer function can be determined by a piecewise function, such as the function represented in Figure 5 In one embodiment, the discharge / charge buffer function block 350 determines the charge buffer value based on the battery peak charge voltage value predicted by the peak voltage prediction block 340. The charge buffer function can be determined by a piecewise function, such as Figure 6 The function shown.

[0054] In one embodiment, the temperature buffer function block 360 determines the value of a temperature buffer function, where the temperature buffer function is a weighted function that represents a limit on the ability of the battery cell 215 to charge or discharge current. In one embodiment, the temperature buffer function is defined based on the temperature of each battery component and is represented as Figure 7 The value of the temperature buffer function at two maximum temperatures T max,1 and T max,2 The temperature buffer function gradually decreases from 1 to 0. Different batteries may have different temperature buffer functions; however, in the main embodiment, the following three temperature buffer functions are required:

[0055] Battery temperature buffer function: The maximum temperature of all batteries in the battery pack 210 should be considered when determining the battery current capacity. max The limit can be set to 40°C, the second T max The limit can be set to 55°C.

[0056] Module temperature buffer function: The maximum temperature of all modules in the battery pack 210 should be considered when determining the battery current capacity. max The limit can be set to 40°C, the second T max The limit can be set to 70°C.

[0057] Battery pack component temperature buffer function: The maximum temperature of at least one battery pack component in the battery pack 210 should be considered when determining the battery current capacity. max The limit can be set to 40°C, the second T max The limit can be set to 100°C.

[0058] In one embodiment, the battery discharge / charge current capacity block 370 is based on I dischg,peak , I chg,peak , I dischg,cont, I chg,cont The maximum discharge current value I is determined by the multiple buffer values ​​determined by the charge / discharge voltage buffer function block 350 and the temperature buffer function block 360. dischg,max and the maximum charging current value I chg,max .

[0059] In one embodiment, the maximum current capacity of the battery can be defined as the value between the peak current limit and the continuous current limit as follows:

[0060] I dischg,max =α dischg ×I dischg,peak +(1-α dischg )×I dischg,cont

[0061] I chg,max =α chg ×I chg,peak +(1-α chg )×I chg,cont

[0062] Where α is the buffer function, a weighted function with values ​​between 0 and 1. In one embodiment, this function represents the battery's ability to handle peak discharge or charge current. In one embodiment, if the buffer value is 1, the battery is 100% capable of discharging at the peak discharge current value (or charging at the peak charge current value), while if the buffer value is 0, it is 0%. In one embodiment, to quantify the buffer function, it is necessary to quantify the battery's limitations that prevent the battery from using 100% of the peak current.

[0063] In one embodiment, α dischg and α chg is determined as a minimum value from a set of corresponding values ​​determined by the discharge / charge voltage buffer function block 350 and the temperature buffer function block 360, such that if any one of the buffer values ​​produced by either block 350 and 360 indicates a condition that would limit or prevent the battery cell from providing peak discharge power or receiving peak charge power, then α dischg and α chg The battery discharge / charge current capacity block 370 is lowered and weighs the continuous current value more heavily when determining the present maximum discharge / charge current value.

[0064] In one embodiment, the maximum voltage prediction block 380 predicts the battery voltage based on the discharge and charge maximum current limits determined by the battery discharge / charge current capacity block 370. The maximum voltage prediction block 380 may use the same functions and RC model 400 as the peak voltage prediction block 340, except that the I dischg,max and I chg,max As input instead of I dischg,peak and I chg,peakas input.

[0065] In one embodiment, the power capacity calculation block 390 is based on I dischg,max , I chg,max The maximum discharge power and the maximum charge power are determined based on the battery voltage predicted at the maximum voltage prediction block 380. In one embodiment, the maximum discharge power and the maximum charge power can be determined as follows:

[0066] P dischg,max =I dischg,max ×V dischg,predict

[0067] P chg,max =I chg,max ×V chg,predict

[0068] While the present disclosure refers to exemplary embodiments, workers skilled in the art will understand that various changes in form and details may be made therein without departing from the scope of the claimed embodiments.

Claims

1. A method for estimating a maximum power limit of a battery cell at a specified prediction time, comprising: determining a plurality of battery cell parameters; determining a peak current limit and a continuous current limit based on at least one of the plurality of battery cell parameters; determining a predicted peak voltage using an RC equivalent circuit model of the battery cell, wherein at least one of the plurality of RC equivalent circuit model parameters is set based on the specified prediction time, at least one of the plurality of battery cell parameters, and the peak current limit; determining a voltage buffer value based on the predicted peak voltage, wherein the voltage buffer value is a weight function value representing a limit on a charge or discharge current capability of the battery cell; determining a temperature buffer value based on a plurality of temperature measurements, wherein the temperature buffer value is a weight function value representing a limit on a charge or discharge current capability of the battery cell; determining a maximum current limit based on a weight function applied to the peak current limit and the continuous current limit, wherein the weight function value is determined based on the voltage buffer value and the temperature buffer value; determining a predicted maximum voltage based on the RC equivalent circuit model of the battery, wherein at least one of the plurality of RC equivalent circuit model parameters is set based on the specified prediction time, at least one of the plurality of battery cell parameters, and the maximum current limit; and determining the maximum power limit based on the maximum current limit and the maximum voltage limit.

2. The method according to claim 1, wherein The plurality of battery cell parameters include at least one of a state of charge of the battery cell, a temperature of the battery cell, and a state of health of the battery cell.

3. The method according to claim 1, wherein The maximum power limit is a maximum discharge power limit, the peak current limit is a peak discharge current limit, and the continuous current limit is a continuous discharge current limit.

4. The method according to claim 1, wherein The maximum power limit is a maximum charging power limit, the peak current limit is a peak charging current limit, and the continuous current limit is a continuous charging current limit.

5. The method according to claim 1, wherein The battery cell is a battery cell included in a battery module, and the battery module includes at least one battery cell.

6. The method according to claim 5, wherein: The battery module is a battery module included in a battery pack, and the battery pack includes at least one battery module.

7. The method according to claim 6, wherein: The plurality of temperature measurements includes at least one measurement from the set of a maximum battery cell temperature, a maximum battery module temperature, and a maximum battery pack component temperature.

8. The method according to claim 1, wherein The plurality of temperature measurements includes a temperature of at least one device associated with the battery cell by being in proximity to the battery cell.

9. The method according to claim 1, wherein: The plurality of temperature measurements includes a temperature of at least one device associated with the battery cell via an electrical connection to the battery cell.

10. The method according to claim 1, wherein As part of determining the predicted peak voltage and the predicted maximum voltage, the RC equivalent circuit model performs a state of charge calculation to determine a predicted state of charge after the specified predicted time has elapsed.

11. A system for estimating a maximum power limit of a battery cell at a specified forecast time, comprising: A sensor system, wherein the sensor system is configured to receive a plurality of temperature measurements from a plurality of temperature sensors; and a controller, wherein the controller is configured to receive data of a plurality of battery cell parameters and the plurality of temperature measurements from the sensor system, and wherein the controller is configured to estimate a maximum power limit of the battery cell using a method, the method comprising: determining a peak current limit and a continuous current limit based on at least one of the plurality of battery cell parameters; determining a predicted peak voltage using an RC equivalent circuit model of the battery cell, wherein at least one of the plurality of RC equivalent circuit model parameters is set based on the specified predicted time, at least one of the plurality of battery cell parameters, and the peak current limit; determining a voltage buffer value based on the predicted peak voltage, A voltage buffer value is a weighted function value representing a limitation on the charging or discharging current capability of the battery cell; a temperature buffer value is determined based on a plurality of temperature measurement values, the temperature buffer value being a weighted function value representing a limitation on the charging or discharging current capability of the battery cell; a maximum current limit is determined based on a weighted function applied to the peak current limit and the continuous current limit, wherein the weighted function value is determined based on the voltage buffer value and the temperature buffer value; a predicted maximum voltage is determined based on the RC equivalent circuit model of the battery, wherein at least one of the plurality of RC equivalent circuit model parameters is set based on the specified prediction time, at least one of the plurality of battery cell parameters, and the maximum current limit; and the maximum power limit is determined based on the maximum current limit and the maximum voltage limit.

12. The system according to claim 11, wherein The plurality of battery cell parameters include at least one of a state of charge of the battery cell, a temperature of the battery cell, and a state of health of the battery cell.

13. The system according to claim 11, wherein: The maximum power limit is a maximum discharge power limit, the peak current limit is a peak discharge current limit, and the continuous current limit is a continuous discharge current limit.

14. The system according to claim 11, wherein: The maximum power limit is a maximum charging power limit, the peak current limit is a peak charging current limit, and the continuous current limit is a continuous charging current limit.

15. The system according to claim 11, wherein The battery cell is a battery cell included in a battery module, and the battery module includes at least one battery cell.

16. The system according to claim 15, wherein: The battery module is a battery module included in a battery pack, and the battery pack includes at least one battery module.

17. The system according to claim 16, wherein: The plurality of temperature measurements includes at least one measurement from the set of a maximum battery cell temperature, a maximum battery module temperature, and a maximum battery pack component temperature.

18. The system according to claim 11, wherein: The plurality of temperature measurements includes a temperature of at least one device associated with the battery cell by being in proximity to the battery cell.

19. The system according to claim 11, wherein: The plurality of temperature measurements includes a temperature of at least one device associated with the battery cell via an electrical connection to the battery cell.

20. The system of claim 11, wherein: As part of determining the predicted peak voltage and the predicted maximum voltage, the RC equivalent circuit model performs a state of charge calculation to determine a predicted state of charge after the specified predicted time has elapsed.

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