Battery charging and discharging simulation method, device, computer equipment and storage medium

Abstract

The present application relates to a battery charge and discharge simulation method, device, computer equipment and storage medium. According to the current distribution of the initial equivalent circuit model of the solid-state battery within the preset charge and discharge simulation time, the initial current of the active particles in the initial equivalent circuit model and the initial output voltage of the initial equivalent circuit model are determined, and the initial state information of the active particles in the initial equivalent circuit model is updated according to the initial current to obtain the new state information after the current update. Based on the current total charge and discharge simulation time, the preset total charge and discharge simulation time, the initial output voltage, the initial state information and the new state information, the charge and discharge simulation results of the solid-state battery are determined. Since the active particles of the solid-state battery undergo mechanical changes such as expansion or contraction during the charge and discharge process, the present application uses an equivalent circuit model to determine the charge and discharge simulation results, and simulates the impact of the solid-solid contact evolution that occurs during the charge and discharge process of the solid-state battery as the active particles expand on the performance of the solid-state battery.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery charge and discharge simulation method, device, computer equipment, and storage medium. Background Art

[0002] Compared with traditional liquid lithium-ion batteries, solid-state batteries have advantages such as high safety, high energy density, and a wide operating temperature range. However, the performance research of solid-state batteries requires a lot of experimental verification. Simulation technology can quickly simulate the performance of solid-state batteries in a virtual environment, reducing the number of experiments, reducing R&D costs, and shortening the R&D cycle.

[0003] Because solid-state batteries use solid electrolytes instead of liquid electrolytes, the evolution of solid-solid contact during charge and discharge, as active particles expand, has a significant impact on their performance. Therefore, a simulation method that can capture this evolution during charge and discharge is urgently needed to study the performance of solid-state batteries. Summary of the Invention

[0004] Based on this, it is necessary to provide a battery charging and discharging simulation method, device, computer equipment and storage medium that can reflect the evolution of solid-solid contact during charging and discharging to address the above technical problems.

[0005] In a first aspect, the present application provides a battery charge and discharge simulation method, comprising:

[0006] Determining, based on the current distribution of the initial equivalent circuit model of the solid-state battery within a preset charge and discharge simulation time, the initial current of the active particles in the initial equivalent circuit model and the initial output voltage of the initial equivalent circuit model; the initial current is determined based on the inflow current and outflow current of the active particles;

[0007] updating the initial state information of the active particles in the initial equivalent circuit model according to the initial current to obtain new state information after the current update;

[0008] Based on the current total charge and discharge simulation time, the preset total charge and discharge simulation time, the initial output voltage, the initial state information and the new state information, the charge and discharge simulation result of the solid-state battery is determined.

[0009] In one embodiment, determining the charge and discharge simulation result of the solid-state battery based on the current charge and discharge simulation total time, the preset charge and discharge simulation total time, the initial output voltage, the initial state information, and the new state information includes:

[0010] If the current total charge and discharge simulation time is less than the preset total charge and discharge simulation time, a loop operation is performed; the loop operation includes: determining a new equivalent circuit model according to the new state information, determining a new current of the active particles in the new equivalent circuit model and a new output voltage of the new equivalent circuit model according to a new current distribution of the new equivalent circuit model within the preset charge and discharge simulation time, and updating the new state information of the active particles in the new equivalent circuit model according to the new current to obtain the new state information after the next update, until the current total charge and discharge simulation time is not less than the preset total charge and discharge simulation time;

[0011] The charge and discharge simulation results of the solid-state battery are determined based on the initial state information, the initial output voltage, the new state information and the new output voltage obtained each time.

[0012] In one embodiment, updating the initial state information of the active particles in the initial equivalent circuit model according to the initial current to obtain the new state information after the current update includes:

[0013] updating the initial lithium insertion state of the active particles in the initial equivalent circuit model according to the initial current of the active particles in the initial equivalent circuit model and the preset charge and discharge simulation time to obtain the currently updated lithium insertion state;

[0014] updating the initial volume of the active particles in the initial equivalent circuit model based on the currently updated lithium intercalation state to obtain the currently updated volume;

[0015] According to the volume after the current update, the initial radius of the active particle in the initial equivalent circuit model is updated to obtain the radius after the current update; the new state information includes the lithium insertion state after the current update and the radius after the current update.

[0016] In one embodiment, updating the initial lithium insertion state of the active particles in the initial equivalent circuit model according to the initial current and the preset charge and discharge simulation time to obtain the currently updated lithium insertion state includes:

[0017] Determining a change in the lithium insertion state of the active particles in the initial equivalent circuit model according to the preset charge and discharge simulation time, the initial current of the active particles in the initial equivalent circuit model, the maximum ion concentration, and the initial volume;

[0018] The lithium insertion state after the current update is determined according to the initial lithium insertion state and the change in the lithium insertion state of the active particles in the initial equivalent circuit model.

[0019] In one embodiment, updating the initial volume of the active particles in the initial equivalent circuit model based on the currently updated lithium-intercalated state to obtain the currently updated volume includes:

[0020] Determining a current volume change rate of the active particles in the initial equivalent circuit model based on the currently updated lithium insertion state and a preset corresponding relationship; the preset corresponding relationship is a corresponding relationship between the volume change rate of the active particles and the lithium insertion state;

[0021] The initial volume of the active particles in the initial equivalent circuit model is updated according to the current volume change rate to obtain the currently updated volume.

[0022] In one embodiment, determining a new equivalent circuit model according to the new state information includes:

[0023] Determining, based on the new state information, the radius of a contact surface between two particles in a particle group that are in contact with each other; wherein the particle group includes three particles of at least one of active particles and / or solid electrolyte particles;

[0024] Obtaining a product of the radius and pi;

[0025] determining a bulk resistance corresponding to current transmission through the intermediate particle based on the conductivity of the intermediate particle, the target distance, and the product; the intermediate particle being a particle in the particle group that is in contact with two particles simultaneously, and the target distance being the distance between the two contact surfaces;

[0026] The new equivalent circuit model is determined based on the reaction resistances, the contact resistances and the bulk resistances.

[0027] In a second aspect, the present application also provides a battery charge and discharge simulation device, comprising:

[0028] A first determination module is configured to determine, based on a current distribution of an initial equivalent circuit model of the solid-state battery within a preset charge and discharge simulation time, an initial current of active particles in the initial equivalent circuit model and an initial output voltage of the initial equivalent circuit model; the initial current is determined based on an inflow current and an outflow current of the active particles;

[0029] a second determining module, configured to update the initial state information of the active particles in the initial equivalent circuit model according to the initial current, to obtain new state information after the current update;

[0030] The third determination module is used to determine the charge and discharge simulation results of the solid-state battery based on the current charge and discharge simulation total time, the preset charge and discharge simulation total time, the initial output voltage, the initial state information and the new state information.

[0031] In a third aspect, the present application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the method steps provided in the first aspect when executing the computer program.

[0032] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which implements the method steps provided in the first aspect when the computer program is executed by a processor.

[0033] In a fifth aspect, the present application also provides a computer program product, comprising a computer program, which implements the method steps provided in the first aspect when executed by a processor.

[0034] The above-mentioned battery charge and discharge simulation method, device, computer equipment and storage medium determine the initial current of the active particles in the initial equivalent circuit model and the initial output voltage of the initial equivalent circuit model based on the current distribution of the initial equivalent circuit model of the solid-state battery within the preset charge and discharge simulation time, update the initial state information of the active particles in the initial equivalent circuit model according to the initial current, obtain the new state information after the current update, and determine the charge and discharge simulation results of the solid-state battery based on the current total charge and discharge simulation time, the preset total charge and discharge simulation time, the initial output voltage, the initial state information and the new state information; the initial current is determined according to the inflow current and outflow current of the active particles. Since the active particles of solid-state batteries undergo mechanical changes such as expansion or contraction during the charging and discharging process, in an embodiment of the present application, an initial equivalent circuit model is constructed using the initial state information of the solid-state battery, and the initial state information is updated using the initial equivalent circuit model to obtain new state information during the charging and discharging process, thereby determining the charging and discharging simulation results based on the new state information, the initial state information, the initial output voltage, and the new output voltage. The present application uses an equivalent circuit model to determine the charging and discharging simulation results, and simulates the impact of the solid-solid contact evolution that occurs during the charging and discharging process of the solid-state battery as the active particles expand on the performance of the solid-state battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present application or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 A diagram illustrating an application environment of a battery charge and discharge simulation method according to an embodiment;

[0037] Figure 21 is a flow chart of a battery charge and discharge simulation method according to an embodiment;

[0038] Figure 3 is a schematic diagram of an initial equivalent circuit model in one embodiment;

[0039] Figure 4 is a schematic diagram of an initial equivalent circuit model in another embodiment;

[0040] Figure 5 is a schematic diagram of an initial equivalent circuit model in another embodiment;

[0041] Figure 6 is a schematic diagram of initial state information in one embodiment;

[0042] Figure 7 is a schematic diagram of a conductive network corresponding to initial state information in one embodiment;

[0043] Figure 8 is a schematic diagram of new status information in one embodiment;

[0044] Figure 9 is a schematic diagram of a conductive network corresponding to initial state information in one embodiment;

[0045] Figure 10 Schematic diagram of discharge simulation results under two working conditions in one embodiment;

[0046] Figure 11 A schematic diagram of the change in the results of charge-discharge cycle simulation of a contact pair in one embodiment;

[0047] Figure 12 1 is a flow chart of a method for determining new state information in one embodiment;

[0048] Figure 13 2 is a flow chart of a method for determining a lithium intercalation state after a current update in one embodiment;

[0049] Figure 14 is a flow chart of a battery charge and discharge simulation method according to another embodiment;

[0050] Figure 15 FIG. 4 is a structural block diagram of a battery charge and discharge simulation device in one embodiment. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0052] The battery charge and discharge simulation method provided in the embodiment of the present application can be applied to Figure 1 The application environment shown in FIG. The application environment includes a computer device, which may be a server, and its internal structure diagram may be as shown in FIG. Figure 1 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O) and a communication interface. The processor, memory and input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The database of the computer device is used to store relevant data of battery charge and discharge simulation. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a battery charge and discharge simulation method is implemented. The server can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides cloud computing services.

[0053] Those skilled in the art will understand that Figure 1 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0054] In an exemplary embodiment, Figure 2 As shown, a battery charge and discharge simulation method is provided, which is applied to Figure 1 The computer device in the example is used to illustrate, including the following S201 to S203.

[0055] S201, based on the current distribution of the initial equivalent circuit model of the solid-state battery within a preset charge and discharge simulation time, determine the initial current of the active particles in the initial equivalent circuit model and the initial output voltage of the initial equivalent circuit model; the initial current is determined based on the inflow current and outflow current of the active particles.

[0056] Solid-state batteries consist of five components: a positive electrode, a negative electrode, a separator, a positive current collector, and a negative current collector. Both the positive and negative electrodes are composite electrodes composed of active material (AM) and solid electrolyte particles (SE). The separator is composed of solid electrolyte particles, and the positive and negative current collectors are metal foil.

[0057] Initialize the radius and position of the solid-state battery's active and solid electrolyte particles, as well as the lithium insertion state of the positive electrode particles (AM and SE) and the negative electrode particles (AM and SE). Particle initialization can be performed using discrete element simulation software to simulate the solid-state battery's cold pressing process. This generates a set of positive and negative electrode sheets and separators that conform to the electrode design, distribution of the positive and negative electrode active particles and solid electrolyte particles, and the ratio of active material to solid electrolyte particles in the electrode. A given manufacturing pressure is then applied and gradually released until the operating pressure is reached. The manufacturing pressure is several hundred MPa, and the operating pressure is MPa. The particles are initialized to a lithium insertion state of SOC0. After initialization, the positive electrode SOC0 is between 0 and 1.0, and the negative electrode SOC0 is between 0 and 1.0. The initial particle radius is R0, and the total duration of the current charge and discharge simulation is initialized to 0. If the solid-state battery is initially in a fully discharged state, the negative electrode SOC0 is greater than the negative electrode SOC0. If the solid-state battery is initially in a fully charged state, the positive electrode SOC0 is greater than the negative electrode SOC0.

[0058] An initial equivalent circuit model is established based on the initialized solid-state battery. Specifically, based on the type of particles in the initialized solid-state battery (active particles or solid electrolyte particles), the initial radius and initial position of each particle, and the mass ratio of the solid electrolyte particles and the active particles, a compaction simulation is performed under a given pressure using discrete elements to determine the initial contact state between the positive and negative electrode particles. An initial equivalent circuit model is established based on the initial contact state between the particles. The initial equivalent circuit model is as follows: Figure 3 and Figure 4 The initial equivalent circuit model consists of three parts: ion network, electronic network and reaction network. The ion network is composed of solid electrolyte particles, the electronic network is composed of active particles and current collectors, and the reaction network is composed of active particles and solid electrolyte particles.

[0059] Since electron current encounters resistance when passing through active particles or ion current through solid electrolyte particles, this resistance is the bulk resistance R b The resistance of the electrochemical reaction when the current passes through the active particles and the electrolyte interface of the active particles is the reaction resistance R bv , and the resistance when the current passes through the contact interface (for example, positive electrode-solid electrolyte particles, solid electrolyte particles-active particles) is the contact resistance R cFurthermore, the schematic diagram of the initial equivalent circuit model can also be as follows Figure 5 shown.

[0060] Since the state of the solid electrolyte particles does not change substantially during the charge and discharge process, in an embodiment of the present application, a current is input into the initial equivalent circuit model to simulate the charge and discharge process of the solid-state battery, so as to use discrete elements to obtain the current distribution of the initial equivalent circuit model within the preset charge and discharge simulation time. The initial current of each active particle is determined only based on the current distribution. For example, a current of 10A is input into the initial equivalent circuit model to simulate the charging process of the solid-state battery. The inflow current and outflow current of each active particle can be obtained according to the current distribution. The initial current of the active particle can be obtained by subtracting the outflow current from the inflow current. If the discharge process of the solid-state battery is simulated, a current of -10A can be input into the initial equivalent circuit model.

[0061] The initial output voltage can be calculated based on an equivalent circuit constructed from the initial structure. Alternatively, the current flowing through the initial equivalent circuit model can be determined based on the current distribution, and the initial output voltage can be determined based on the current flowing through the initial equivalent circuit model and the actual resistance value of the current flowing through the initial equivalent circuit model.

[0062] S202 : updating the initial state information of the active particles in the initial equivalent circuit model according to the initial current to obtain new state information after the current update.

[0063] In the embodiment of the present application, the initial state information is as follows: Figure 6 As shown, the conductive network (electronic network, ionic network and reaction network) corresponding to the initial state information is as follows Figure 7 As shown, the initial lithium insertion state of the active particles in the initial equivalent circuit model can be updated according to the initial current of the active particles in the initial equivalent circuit model and the preset charge and discharge simulation time to obtain the lithium insertion state after the current update, and the initial volume of the active particles in the initial equivalent circuit model is updated based on the lithium insertion state after the current update to obtain the volume after the current update, and the initial radius of the active particles in the initial equivalent circuit model is updated according to the volume after the current update to obtain the radius after the current update; the new state information includes the lithium insertion state after the current update and the radius after the current update.

[0064] In one possible implementation, after obtaining the radius after the current update, the discrete element simulation software is run based on the updated radius to obtain the current updated position and contact state of the active particles and the electrolyte particles under the working pressure, that is, the current relative position and contact state of the active particles and the electrolyte particles have changed compared to the initial state; the new state information also includes the current updated position and contact state. The new state information is as follows: Figure 8 As shown, the conductive network corresponding to the new state information is as follows Figure 9 shown.

[0065] S203 , determining a charge and discharge simulation result of the solid-state battery based on the current charge and discharge simulation total time, the preset charge and discharge simulation total time, the initial output voltage, the initial state information, and the new state information.

[0066] In an embodiment of the present application, if the current total charge and discharge simulation time is less than the preset total charge and discharge simulation time, the initial equivalent circuit model is updated according to the new state information to obtain a new equivalent circuit model, that is, the new equivalent circuit model is determined according to the new state information. According to the new current distribution of the new equivalent circuit model within the preset charge and discharge simulation time, the new current of the active particles in the new equivalent circuit model and the new output voltage of the new equivalent circuit model are determined, and the new state information of the active particles in the new equivalent circuit model is updated according to the new current to obtain the new state information after the next update, until the current total charge and discharge simulation time is not less than the preset total charge and discharge simulation time. The charge and discharge simulation results of the solid-state battery are determined based on the initial state information, the initial output voltage, the new state information obtained each time, and the new output voltage.

[0067] In one possible implementation, if the current total charge and discharge simulation time is not less than the preset total charge and discharge simulation time, the charge and discharge simulation result of the solid-state battery is determined directly based on the initial state information and the new state information.

[0068] In the above-mentioned battery charge and discharge simulation method, the initial current of the active particles in the initial equivalent circuit model and the initial output voltage of the initial equivalent circuit model are determined based on the current distribution of the initial equivalent circuit model of the solid-state battery within the preset charge and discharge simulation time. The initial state information of the active particles in the initial equivalent circuit model is updated according to the initial current to obtain the new state information after the current update. The charge and discharge simulation results of the solid-state battery are determined based on the current total charge and discharge simulation time, the preset total charge and discharge simulation time, the initial output voltage, the initial state information and the new state information; the initial current is determined based on the inflow current and outflow current of the active particles. Since the active particles of solid-state batteries undergo mechanical changes such as expansion or contraction during the charging and discharging process, in an embodiment of the present application, an initial equivalent circuit model is constructed using the initial state information of the solid-state battery, and the initial state information is updated using the initial equivalent circuit model to obtain new state information during the charging and discharging process, thereby determining the charging and discharging simulation results based on the new state information, the initial state information, the initial output voltage, and the new output voltage. The present application uses an equivalent circuit model to determine the charging and discharging simulation results, and simulates the impact of the solid-solid contact evolution that occurs during the charging and discharging process of the solid-state battery as the active particles expand on the performance of the solid-state battery.

[0069] In one embodiment, based on the current total charge and discharge simulation time, the preset total charge and discharge simulation time, the initial output voltage, the initial state information, and the new state information, determining the charge and discharge simulation results of the solid-state battery includes:

[0070] If the current total charge and discharge simulation time is less than the preset total charge and discharge simulation time, a loop operation is performed; the loop operation includes: determining a new equivalent circuit model based on the new state information, determining the new current of the active particles in the new equivalent circuit model and the new output voltage of the new equivalent circuit model based on the new current distribution of the new equivalent circuit model within the preset charge and discharge simulation time, and updating the new state information of the active particles in the new equivalent circuit model according to the new current to obtain the new state information after the next update, until the current total charge and discharge simulation time is not less than the preset total charge and discharge simulation time; determining the charge and discharge simulation results of the solid-state battery based on the initial state information, the initial output voltage, the new state information obtained each time, and the new output voltage.

[0071] In an embodiment of the present application, multiple durations corresponding to different lithium insertion states can be set within the total charge and discharge simulation duration, namely, a first charge duration, a first discharge duration, a second charge duration, a second discharge duration, etc. For example, if the total charge and discharge simulation duration is 60 minutes, 0-10 minutes is the interval corresponding to the first charge duration, 10-20 minutes is the interval corresponding to the first discharge duration, 20-30 minutes is the interval corresponding to the second charge duration, 30-40 minutes is the interval corresponding to the second discharge duration, 40-50 minutes is the interval corresponding to the third charge duration, and 50-60 minutes is the interval corresponding to the third discharge duration.

[0072] When the current total charge and discharge simulation time is less than the preset total charge and discharge simulation time, the relationship between the current total charge and discharge simulation time and each charging time / discharging time is further determined. For example, if the total charge and discharge simulation time is 60 minutes, the current total charge and discharge simulation time is 9 minutes, which is located in the interval corresponding to the first charging time, then according to the new state information, a new equivalent circuit model is determined, and a current of 10A is input to the new equivalent circuit model to simulate the charging process of the solid-state battery. The new current distribution of the equivalent circuit model within the preset charge and discharge simulation time is obtained, and the new current and new output voltage are determined based on the new current distribution, thereby obtaining the new state information after the next update. If the preset charge and discharge simulation time is 2 minutes, then the current total charge and discharge simulation time is 11 minutes, the current total charge and discharge simulation time is less than the total charge and discharge simulation time of 60 minutes, and the current total charge and discharge simulation time of 11 minutes is located in the interval corresponding to the first discharge time, then according to the new state information after the last update, a new equivalent circuit model is determined, and a current of -10A is input to the new equivalent circuit model to simulate the discharge process of the solid-state battery. Obtain the new current distribution of the equivalent circuit model within the preset charge and discharge simulation time, determine the new current and new output voltage based on the new current distribution, and thus obtain the new state information after the next update. Continue to repeat the above iterative process to obtain the new state information and new output voltage after each update.

[0073] According to the new output voltage and the initial output voltage, the simulation results of the output voltage during the charge and discharge process can be obtained. The results are as follows: Figure 10 As shown in the figure, it represents the discharge 1C curve under different working conditions (different working pressures).

[0074] According to the new state information and initial state information of each time, the simulation results of the contact pair during the charge and discharge cycle can be obtained. The results are as follows: Figure 11 shown.

[0075] In the embodiment of the present application, if the current charge and discharge simulation total time is less than the preset charge and discharge simulation total time, a loop operation is performed; the loop operation includes: determining a new equivalent circuit model according to the new state information, determining the new current of the active particles in the new equivalent circuit model and the new output voltage of the new equivalent circuit model according to the new current distribution of the new equivalent circuit model within the preset charge and discharge simulation time, and updating the new state information of the active particles in the new equivalent circuit model according to the new current, obtaining the new state information after the next update, until the current charge and discharge simulation total time is not less than the preset charge and discharge simulation total time; determining the charge and discharge simulation results of the solid-state battery according to the initial state information, the initial output voltage, the new state information obtained each time, and the new output voltage. The embodiment of the present application reflects the change of solid-solid contact caused by the expansion of active particles during the charge and discharge process by updating the state information caused by the expansion of active particles, and updating the initial equivalent circuit model using the new state information, obtaining the charge and discharge simulation results based on the state information and output voltage obtained by the new equivalent circuit model, and simulating the effect of the expansion of active particles on the electrochemical performance during the charge and discharge process of the solid-state battery.

[0076] Figure 12 FIG. 1 is a flow chart of a method for determining new state information in one embodiment. Figure 12 As shown, the embodiment of the present application relates to a possible implementation method of how to update the initial state information of the active particles in the initial equivalent circuit model according to the initial current to obtain the new state information after the current update, including the following steps:

[0077] S1201 , updating the initial lithium insertion state of the active particles in the initial equivalent circuit model according to the initial current of the active particles in the initial equivalent circuit model and the preset charge and discharge simulation time, to obtain the currently updated lithium insertion state.

[0078] In an embodiment of the present application, the change in the lithium intercalation state of the active particles in the initial equivalent circuit model can be determined based on the preset charge and discharge simulation time, the initial current, the maximum ion concentration and the initial volume of the active particles in the initial equivalent circuit model. The lithium intercalation state after the current update can be determined based on the initial lithium intercalation state and the change in the lithium intercalation state of the active particles in the initial equivalent circuit model.

[0079] In one possible implementation, the initial current can be integrated over a preset charge and discharge simulation time according to a current integration method, thereby updating the initial lithium insertion state of the active particles in the initial equivalent circuit model to obtain the lithium insertion state after the current update.

[0080] S1202: Update the initial volume of the active particles in the initial equivalent circuit model based on the currently updated lithium-intercalated state to obtain the currently updated volume.

[0081] In an embodiment of the present application, based on the currently updated lithium-intercalation state and the preset correspondence, the current volume change rate of the active particles in the initial equivalent circuit model is determined, and the initial volume of the active particles in the initial equivalent circuit model is updated according to the current volume change rate to obtain the volume after the current update, wherein the preset correspondence is the correspondence between the volume change rate of the active particles and the lithium-intercalation state, and the preset correspondence can be applied to all active particles.

[0082] In a possible implementation, the volume after the current update can also be obtained directly based on the preset correspondence between the lithium insertion state after the current update and the active particle. In this case, the preset correspondence is the correspondence between the volume of each active particle and the lithium insertion state.

[0083] S1203, based on the volume after the current update, updating the initial radius of the active particle in the initial equivalent circuit model to obtain the radius after the current update; the new state information includes the lithium insertion state after the current update and the radius after the current update.

[0084] In the embodiment of the present application, based on the relationship between volume V and radius R , we can get the radius after the current update corresponding to the volume after the previous update.

[0085] In an embodiment of the present application, the initial lithium insertion state of the active particles in the initial equivalent circuit model is updated based on the initial current of the active particles in the initial equivalent circuit model and the preset charge and discharge simulation time to obtain the lithium insertion state after the current update. The initial volume of the active particles in the initial equivalent circuit model is updated based on the lithium insertion state after the current update to obtain the volume after the current update. Based on the volume after the current update, the initial radius of the active particles in the initial equivalent circuit model is updated to obtain the radius after the current update, thereby improving the efficiency of updating the new state information.

[0086] Figure 13 FIG. 1 is a flow chart of a method for determining the lithium intercalation state after the current update in one embodiment. Figure 13 As shown, the embodiment of the present application relates to a possible implementation method of how to update the initial lithium insertion state of the active particles in the initial equivalent circuit model according to the initial current and the preset charge and discharge simulation time to obtain the current updated lithium insertion state, including the following steps:

[0087] S1301, determining a change in the lithium insertion state of the active particles in the initial equivalent circuit model according to a preset charge and discharge simulation time, an initial current, a maximum ion concentration, and an initial volume of the active particles in the initial equivalent circuit model.

[0088] S1302: Determine the lithium intercalation state after the current update based on the initial lithium intercalation state and the change in the lithium intercalation state of the active particles in the initial equivalent circuit model.

[0089] In the embodiment of the present application, it is assumed that the initial equivalent circuit model of the solid-state battery is set to the preset charge and discharge simulation time. It is approximately constant over time, so The number of ions flowing into the active particles in a given time is , where F is the Faraday constant and I0 is the initial current of the active particle. The change in the lithium insertion state of each active particle is determined based on the number of ions, maximum ion concentration, and initial volume. ; Where V0 is the initial volume of each active particle, C max is the maximum ion concentration of active particles.

[0090] By adding the initial lithium insertion state and the lithium insertion state change, the lithium insertion state after the current update can be obtained as , SOC0 is the initial lithium insertion state.

[0091] In an embodiment of the present application, the change in the lithium insertion state of the active particles in the initial equivalent circuit model is determined based on the preset charge and discharge simulation time, the initial current, the maximum ion concentration and the initial volume of the active particles in the initial equivalent circuit model. The lithium insertion state after the current update is determined based on the initial lithium insertion state and the change in the lithium insertion state of the active particles in the initial equivalent circuit model, laying the foundation for the subsequent update of the initial state information based on the lithium insertion state after the current update.

[0092] In one embodiment, the initial volume of the active particles in the initial equivalent circuit model is updated based on the lithium insertion state after the current update to obtain the volume after the current update, including: determining the current volume change rate of the active particles in the initial equivalent circuit model based on the lithium insertion state after the current update and a preset corresponding relationship; the preset corresponding relationship is the corresponding relationship between the volume change rate of the active particles and the lithium insertion state; and updating the initial volume of the active particles in the initial equivalent circuit model according to the current volume change rate to obtain the volume after the current update.

[0093] In an embodiment of the present application, the preset corresponding relationship is the corresponding relationship between the volume change rate of the active particles and the lithium insertion state. According to the preset corresponding relationship, the volume change rate corresponding to the lithium insertion state after the current update can be obtained. By multiplying the volume change rate by the initial volume, the volume after the current update can be obtained.

[0094] In an embodiment of the present application, based on the lithium-intercalation state after the current update and the preset corresponding relationship, the current volume change rate of the active particles in the initial equivalent circuit model is determined, and the initial volume of the active particles in the initial equivalent circuit model is updated according to the current volume change rate to obtain the volume after the current update, which simplifies the operation of updating the volume of the active particles and improves the efficiency of the volume update, thereby improving the determination of the battery charge and discharge simulation results.

[0095] In one embodiment, a new equivalent circuit model is determined based on the new state information, including: determining the radius of the contact surface of two particles in contact with each other in the particle group based on the new state information; the particle group includes three particles of at least one type of particle among active particles and / or solid electrolyte particles; obtaining the product result of the radius and the pi; determining the corresponding bulk resistance when current is transmitted through the intermediate particle based on the conductivity, target distance and product result of the intermediate particle; the intermediate particle is a particle in the particle group that is in contact with two particles at the same time, and the target distance is the distance between the two contact surfaces; and determining the new equivalent circuit model based on each reaction resistance, each contact resistance and each bulk resistance.

[0096] In the embodiment of the present application, as mentioned above Figure 3-Figure 5 As shown, the particle group includes the first particle, the second particle and the third particle. The first particle contacts the second particle to form a first contact surface, and the second particle contacts the third particle to form a second contact surface. That is, the second particle is an intermediate particle. The first radius r1 of the first contact surface and the second radius r2 of the second contact surface are obtained according to ,in, is the conductivity of the intermediate particles, and L is the target distance.

[0097] Alternatively, the reaction resistance may be defined by the Butler-Volmer equation.

[0098] Since the radius of the active particles and the contact state between particles change after the initial state information is updated, the electronic network, ion network, reaction network, and the reaction resistances, contact resistances and bulk resistances included are re-determined according to the new state information to obtain a new equivalent circuit model based on the reaction resistances, contact resistances and bulk resistances.

[0099] In an embodiment of the present application, the radius of the contact surface of two particles in contact with each other in the particle group is determined based on the new state information, and the product of the radius and pi is obtained; the bulk resistance corresponding to the current transmission through the intermediate particle is determined based on the conductivity of the intermediate particle, the target distance and the product result; and the new equivalent circuit model is determined based on each reaction resistance, each contact resistance and each bulk resistance. In an embodiment of the present application, the accuracy of the bulk resistance determination is improved by obtaining the product of the radius of the contact surface and pi, and determining the bulk resistance based on the product result, thereby improving the accuracy of the new equivalent circuit model determined based on the bulk resistance. An electronic network, an ion network and a reaction network including bulk resistance, contact circuit and reaction resistance are constructed through the new state information, reflecting the decisive role of the electrochemical process on the expansion of active particles. By coupling the new equivalent circuit model, the mechanical expansion coupling electrochemistry of the solid-state battery charging and discharging process is realized.

[0100] Figure 14FIG. 1 is a flow chart of a battery charge and discharge simulation method in another embodiment. Figure 14 As shown, the following steps are included: initializing the state information of the solid-state battery to obtain the initial state information, which includes the initial radius, initial position, initial lithium insertion state of the active particles and solid electrolyte particles, and initializing the total duration t of the current charge and discharge simulation. j is 0. In the first iteration, the initial equivalent circuit model of the solid-state battery is established based on the initial state information, and the initial equivalent circuit model is solved to obtain the initial current distribution. Based on the initial current distribution, the initial current of the active particles in the initial equivalent circuit model and the initial output voltage of the initial equivalent circuit model are determined. The initial state information is updated based on the initial current, that is, the initial lithium insertion state is updated to obtain the lithium insertion state after the current update. The initial radius is updated based on the lithium insertion state after the current update to obtain the radius after the current update. The new state information after the expansion of the active particles (the position after the current update and the contact state after the current update) is obtained based on the radius after the current update. The total time t of the initial current charge and discharge simulation is j Re-judge whether the current total charge and discharge simulation time is less than the preset total charge and discharge simulation time t max If the total duration of the previous charge and discharge simulation is less than the preset total duration of the charge and discharge simulation, the second iteration is entered, and a new equivalent circuit model is determined based on the new state information. The new current of the active particles in the new equivalent circuit model and the new output voltage of the new equivalent circuit model are determined based on the new current distribution of the new equivalent circuit model. The lithium insertion state after the last update is updated according to the new current to obtain the lithium insertion state after the current update. The initial radius is updated based on the lithium insertion state after the current update to obtain the radius after the current update. The new state information after the expansion of the active particles is obtained based on the radius after the current update, and the current total duration of the charge and discharge simulation is updated until the current total duration of the charge and discharge simulation is not less than the preset total duration of the charge and discharge simulation. The charge and discharge simulation results of the solid-state battery are determined based on the initial state information, the initial output voltage, the new state information obtained each time, and the new output voltage.

[0101] Since the active particles of solid-state batteries undergo mechanical changes such as expansion or contraction during the charging and discharging process, in an embodiment of the present application, an initial equivalent circuit model is constructed using the initial state information of the solid-state battery, and the initial state information is updated using the initial equivalent circuit model to obtain new state information during the charging and discharging process, thereby determining the charging and discharging simulation results based on the new state information, the initial state information, the initial output voltage, and the new output voltage. The present application uses an equivalent circuit model to determine the charging and discharging simulation results, and simulates the impact of the solid-solid contact evolution that occurs during the charging and discharging process of the solid-state battery as the active particles expand on the performance of the solid-state battery.

[0102] It should be understood that, although the steps in the flowcharts of the above embodiments are shown in sequence as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the flowcharts of the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0103] Based on the same inventive concept, the present application also provides a battery charge and discharge simulation device for implementing the aforementioned battery charge and discharge simulation method. The solution provided by the device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more battery charge and discharge simulation device embodiments provided below can be found in the above-mentioned limitations of the battery charge and discharge simulation method, and will not be repeated here.

[0104] In an exemplary embodiment, Figure 15 As shown, a battery charge and discharge simulation device is provided, including: a first determination module 1501, a second determination module 1502 and a third determination module 1503, wherein:

[0105] A first determining module 1501 is configured to determine, based on the current distribution of the initial equivalent circuit model of the solid-state battery within a preset charge and discharge simulation time, the initial current of the active particles in the initial equivalent circuit model and the initial output voltage of the initial equivalent circuit model; the initial current is determined based on the inflow current and outflow current of the active particles;

[0106] A second determining module 1502 is configured to update the initial state information of the active particles in the initial equivalent circuit model according to the initial current to obtain new state information after the current update;

[0107] The third determination module 1503 is used to determine the charge and discharge simulation results of the solid-state battery based on the current charge and discharge simulation total time, the preset charge and discharge simulation total time, the initial output voltage, the initial state information and the new state information.

[0108] In one embodiment, the third determination module 1503 is specifically used to perform a loop operation if the current total charge and discharge simulation time is less than the preset total charge and discharge simulation time; the loop operation includes: determining a new equivalent circuit model based on the new state information, determining the new current of the active particles in the new equivalent circuit model and the new output voltage of the new equivalent circuit model based on the new current distribution of the new equivalent circuit model within the preset charge and discharge simulation time, and updating the new state information of the active particles in the new equivalent circuit model according to the new current to obtain the new state information after the next update, until the current total charge and discharge simulation time is not less than the preset total charge and discharge simulation time; determining the charge and discharge simulation results of the solid-state battery based on the initial state information, the initial output voltage, the new state information obtained each time, and the new output voltage.

[0109] In one embodiment, the second determination module 1502 is specifically used to update the initial lithium insertion state of the active particles in the initial equivalent circuit model based on the initial current of the active particles in the initial equivalent circuit model and the preset charge and discharge simulation time to obtain the lithium insertion state after the current update; update the initial volume of the active particles in the initial equivalent circuit model based on the lithium insertion state after the current update to obtain the volume after the current update; update the initial radius of the active particles in the initial equivalent circuit model based on the volume after the current update to obtain the radius after the current update; the new state information includes the lithium insertion state after the current update and the radius after the current update.

[0110] In one embodiment, the second determination module 1502 is specifically used to determine the change in the lithium insertion state of the active particles in the initial equivalent circuit model based on a preset charge and discharge simulation time, the initial current, the maximum ion concentration, and the initial volume of the active particles in the initial equivalent circuit model; and determine the lithium insertion state after the current update based on the initial lithium insertion state and the change in the lithium insertion state of the active particles in the initial equivalent circuit model.

[0111] In one embodiment, the second determination module 1502 is specifically used to determine the current volume change rate of the active particles in the initial equivalent circuit model based on the lithium insertion state after the current update and the preset corresponding relationship; the preset corresponding relationship is the correspondence between the volume change rate of the active particles and the lithium insertion state; the initial volume of the active particles in the initial equivalent circuit model is updated according to the current volume change rate to obtain the volume after the current update.

[0112] In one embodiment, the third determination module 1503 is specifically used to determine the radius of the contact surface of two particles in contact with each other in the particle group based on the new state information; the particle group includes three particles of at least one of active particles and / or solid electrolyte particles; obtain the product result of the radius and pi; determine the corresponding bulk resistance when the current is transmitted through the intermediate particle based on the conductivity, target distance and product result of the intermediate particle; the intermediate particle is a particle in the particle group that is in contact with two particles at the same time, and the target distance is the distance between the two contact surfaces; determine the new equivalent circuit model based on each reaction resistance, each contact resistance and each bulk resistance.

[0113] Each module in the battery charge and discharge simulation device can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in hardware form, or can be stored in a computer device memory in software form, so that the processor can call and execute the corresponding operations of each module.

[0114] In an exemplary embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps of any of the above method embodiments when executing the computer program.

[0115] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above method embodiments are implemented.

[0116] In one embodiment, a computer program product is provided, comprising a computer program, which implements the steps of any of the above method embodiments when executed by a processor.

[0117] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0118] Those skilled in the art will understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), quantum computing-based data processing logic devices, artificial intelligence (AI) processors, and the like.

[0119] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0120] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A battery charge and discharge simulation method, characterized in that: The method comprises: Simulating a solid-state battery under a preset manufacturing pressure to obtain initial state information of each particle in the solid-state battery, and determining an initial equivalent circuit model of the solid-state battery based on the initial state information of each particle; the initial state information includes an initial lithium insertion state, an initial volume, and an initial radius; Determining, based on the current distribution of an initial equivalent circuit model of the solid-state battery within a preset charge and discharge simulation time, an initial current of active particles in the initial equivalent circuit model and an initial output voltage of the initial equivalent circuit model; the initial current is determined based on the inflow current and outflow current of the active particles; the preset charge and discharge simulation time includes multiple charge time periods and multiple discharge time periods, and the charge time periods and the discharge time periods are alternately set; updating the initial state information of the active particles in the initial equivalent circuit model according to the initial current to obtain new state information after the current update; If the current total charge and discharge simulation time is less than the preset total charge and discharge simulation time, a loop operation is performed; the loop operation includes: determining a new equivalent circuit model based on the new state information, determining the new current of the active particles in the new equivalent circuit model and the new output voltage of the new equivalent circuit model based on the new current distribution of the new equivalent circuit model within the preset charge and discharge simulation time, and updating the new state information of the active particles in the new equivalent circuit model according to the new current to obtain the new state information after the next update, until the current total charge and discharge simulation time is not less than the preset total charge and discharge simulation time; determining the charge and discharge simulation results of the solid-state battery based on the initial state information, initial output voltage, new state information and new output voltage obtained each time of the active particles; the charge and discharge simulation results include the relationship between each moment and voltage within the preset charge and discharge simulation time, and the relationship between each moment and contact pairs within the preset charge and discharge simulation time, and the contact pairs are determined based on the initial state information and the new state information obtained each time.

2. The method according to claim 1, characterized in that The updating of the initial state information of the active particles in the initial equivalent circuit model according to the initial current to obtain the new state information after the current update includes: updating the initial lithium insertion state of the active particles in the initial equivalent circuit model according to the initial current of the active particles in the initial equivalent circuit model and the preset charge and discharge simulation time to obtain the currently updated lithium insertion state; updating the initial volume of the active particles in the initial equivalent circuit model based on the currently updated lithium intercalation state to obtain the currently updated volume; According to the volume after the current update, the initial radius of the active particle in the initial equivalent circuit model is updated to obtain the radius after the current update; the new state information includes the lithium insertion state after the current update and the radius after the current update.

3. The method according to claim 2, characterized in that The updating of the initial lithium insertion state of the active particles in the initial equivalent circuit model according to the initial current and the preset charge and discharge simulation time to obtain the currently updated lithium insertion state includes: Determining a change in the lithium insertion state of the active particles in the initial equivalent circuit model according to the preset charge and discharge simulation time, the initial current of the active particles in the initial equivalent circuit model, the maximum ion concentration, and the initial volume; The lithium insertion state after the current update is determined according to the initial lithium insertion state and the change in the lithium insertion state of the active particles in the initial equivalent circuit model.

4. The method according to claim 2, characterized in that The updating of the initial volume of the active particles in the initial equivalent circuit model based on the currently updated lithium intercalation state to obtain the currently updated volume includes: Determining a current volume change rate of the active particles in the initial equivalent circuit model based on the currently updated lithium insertion state and a preset corresponding relationship; the preset corresponding relationship is a corresponding relationship between the volume change rate of the active particles and the lithium insertion state; The initial volume of the active particles in the initial equivalent circuit model is updated according to the current volume change rate to obtain the currently updated volume.

5. The method according to claim 1, characterized in that Determining a new equivalent circuit model according to the new state information includes: Determining, based on the new state information, the radius of a contact surface between two particles in a particle group that are in contact with each other; wherein the particle group includes three particles of at least one of active particles and / or solid electrolyte particles; Obtaining a product of the radius and pi; determining a bulk resistance corresponding to current transmission through the intermediate particle based on the conductivity of the intermediate particle, the target distance, and the product; the intermediate particle being a particle in the particle group that is in contact with two particles simultaneously, and the target distance being the distance between the two contact surfaces; The new equivalent circuit model is determined based on the reaction resistances, the contact resistances and the bulk resistances.

6. A battery charge and discharge simulation device, characterized in that: The device comprises: A first determination module is used to simulate a solid-state battery under a preset manufacturing pressure to obtain initial state information of each particle in the solid-state battery, and determine an initial equivalent circuit model of the solid-state battery based on the initial state information of each particle; determine the initial current of the active particles in the initial equivalent circuit model and the initial output voltage of the initial equivalent circuit model based on the current distribution of the initial equivalent circuit model of the solid-state battery within a preset charge and discharge simulation time; the initial current is determined based on the inflow current and outflow current of the active particles; the preset charge and discharge simulation time includes multiple charging time and multiple discharge time, and the charging time and the discharge time are alternately set; the initial state information includes an initial lithium insertion state, an initial volume, and an initial radius; a second determining module, configured to update the initial state information of the active particles in the initial equivalent circuit model according to the initial current, to obtain new state information after the current update; The third determination module is used to perform a loop operation if the current total charge and discharge simulation time is less than the preset total charge and discharge simulation time; the loop operation includes: determining a new equivalent circuit model according to the new state information, determining the new current of the active particles in the new equivalent circuit model and the new output voltage of the new equivalent circuit model according to the new current distribution of the new equivalent circuit model within the preset charge and discharge simulation time, and updating the new state information of the active particles in the new equivalent circuit model according to the new current to obtain the new state information after the next update, until the current total charge and discharge simulation time is not less than the preset total charge and discharge simulation time; determining the charge and discharge simulation results of the solid-state battery according to the initial state information, initial output voltage, new state information and new output voltage obtained each time of the active particles, the charge and discharge simulation results including the relationship between each moment and voltage within the preset charge and discharge simulation time, and the relationship between each moment and contact pairs within the preset charge and discharge simulation time, the contact pairs being determined based on the initial state information and the new state information obtained each time.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

9. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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