Battery cell cooling strategy optimization method and device, equipment and storage medium

Abstract

The invention provides a battery cell cooling strategy optimization method and device, equipment and a storage medium, and the method comprises the steps: constructing a battery system model of a target battery through a battery system model construction module; the heat calculation module is used for calculating the heat production amount and the heat dissipation amount of the target battery in the charging process based on the battery system model; the cell temperature calculation module calculates the cell temperature variation of the target battery based on the heat production amount and the heat dissipation amount; and the heat calculation module optimizes a battery cell cooling strategy of the target battery based on the battery cell temperature variation. By adopting the method, the battery is cooled, so that the use safety of the battery is ensured, the service life of the battery is prolonged, and the cruising ability and safety of the whole vehicle are improved.

Description

Technical Field

[0001] The present invention relates to the field of battery control, and in particular to a method, device, equipment and storage medium for optimizing a battery cell cooling strategy. Background Art

[0002] With the popularity of new energy vehicles, the safety of power batteries has attracted much attention. In the study, it was found that when the temperature of the vehicle battery is low, the internal resistance of the battery increases, and its own available energy and charging and discharging power performance decrease significantly, which will have a great impact on the vehicle's endurance and power performance; and the battery temperature will not only affect the working state of the battery, but also have an important impact on the safety of the battery. If the battery temperature is too high, it may cause spontaneous combustion and explosion, which will have an adverse effect on the safety of the vehicle. Therefore, how to formulate and optimize the battery cooling strategy to ensure the safety of battery use when cooling the battery, extend the battery life, and improve the endurance and safety of the vehicle has become an urgent problem to be solved. Summary of the invention

[0003] In view of this, the purpose of the present invention is to provide a method, device, equipment and storage medium for optimizing battery cell cooling strategy, so as to ensure the safety of battery use when cooling the battery, extend the battery life, and improve the endurance and safety of the entire vehicle.

[0004] In a first aspect, an embodiment of the present application provides a method for optimizing a battery cell cooling strategy, which is applied to a battery cell cooling strategy optimization system. The system includes a battery system model building module, a heat calculation module, and a battery cell temperature calculation module. The method includes:

[0005] The battery system model building module builds a battery system model of a target battery;

[0006] The heat calculation module calculates the heat generation and heat dissipation of the target battery during the charging process based on the battery system model;

[0007] The battery cell temperature calculation module calculates the battery cell temperature change of the target battery based on the heat generation and the heat dissipation;

[0008] The heat calculation module optimizes the battery cell cooling strategy of the target battery based on the battery cell temperature variation.

[0009] Optionally, the battery system model includes polarization internal resistance, polarization capacitance, pole core ohmic internal resistance, pole tab ohmic internal resistance and simulated power supply, and the polarization internal resistance and the polarization capacitance are connected in parallel and in series with the pole core ohmic internal resistance, the pole tab ohmic internal resistance and the simulated power supply.

[0010] Optionally, the heat calculation module includes a heat generation calculation submodule and a cooling calculation submodule, and the heat calculation module calculates the heat generation and heat dissipation of the target battery during the charging process based on the battery system model, including:

[0011] The heat generation calculation submodule calculates the heat generation of the target battery during the charging process based on the battery system model;

[0012] The cooling calculation submodule calculates the heat dissipation of the target battery during the charging process based on the battery system model.

[0013] Optionally, the heat generation calculation submodule includes a Joule heat calculation unit, a polarization heat calculation unit, a reaction heat calculation unit and a side reaction heat calculation unit, and the heat generation includes Joule heat, polarization heat, reaction heat and side reaction heat;

[0014] The heat generation calculation submodule calculates the heat generation of the target battery during the charging process based on the battery system model, including:

[0015] The Joule heat calculation unit determines the Joule heat according to the charge and discharge current of the target battery, the ohmic internal resistance of the pole core of the target battery, and the ohmic internal resistance of the pole tab of the target battery;

[0016] The polarization heat calculation unit determines the polarization heat according to the charge and discharge current of the target battery and the polarization internal resistance of the target battery;

[0017] The reaction heat calculation unit determines the reaction heat according to the amount of a substance that outputs electrons for the target battery during charge and discharge, the electromotive force of the target battery, and the temperature coefficient of the target battery;

[0018] The side reaction heat calculation unit determines the side reaction heat based on the estimated coefficients of reaction heat and side reaction heat, the Joule heat, the polarization heat, and the reaction heat.

[0019] Optionally, the cooling calculation submodule includes a convection heat dissipation calculation unit and a contact heat exchange calculation unit, and the heat dissipation includes fluid heat dissipation and solid heat dissipation;

[0020] The cooling calculation submodule calculates the heat dissipation of the target battery during the charging process based on the battery system model, including:

[0021] The fluid heat dissipation calculation unit determines the fluid heat dissipation according to the average temperature difference between the fluid and the solid surface on the heat exchange surface, the convection heat transfer area, the convection heat transfer coefficient and the convection heat transfer amount;

[0022] The contact heat exchange calculation unit determines the solid heat dissipation according to the heat flux density per unit area, the thermal conductivity, and the heat transfer area.

[0023] Optionally, the calculating the temperature change of the target battery cell based on the heat generation and the heat dissipation includes:

[0024] Determining a heat change amount according to the heat generation and the heat dissipation;

[0025] The temperature variation of the target battery cell is determined according to the heat variation and the battery cell mass of the target battery.

[0026] Optionally, the optimizing the battery cell cooling strategy of the target battery based on the battery cell temperature variation includes:

[0027] Determine the target temperature of the water cooling plate according to the change in the battery cell temperature, the charge and discharge current of the target battery cell, the fluid temperature, and the total resistance value of the battery cell during the charge and discharge process;

[0028] The water cooling plate parameters in the battery cell cooling system are optimized according to the water cooling plate target temperature.

[0029] In a second aspect, an embodiment of the present application provides a battery cell cooling strategy optimization system, the system comprising a battery system model building module, a heat calculation module and a battery cell temperature calculation module;

[0030] The battery system model building module is used to build a battery system model of a target battery;

[0031] The heat calculation module is used to calculate the heat generation and heat dissipation of the target battery during the charging process based on the battery system model;

[0032] The battery cell temperature calculation module is used to calculate the battery cell temperature change of the target battery based on the heat generation and the heat dissipation;

[0033] The heat calculation module is used to optimize the battery cell cooling strategy of the target battery based on the battery cell temperature change.

[0034] Optionally, the battery system model includes polarization internal resistance, polarization capacitance, pole core ohmic internal resistance, pole tab ohmic internal resistance and simulated power supply, and the polarization internal resistance and the polarization capacitance are connected in parallel and in series with the pole core ohmic internal resistance, the pole tab ohmic internal resistance and the simulated power supply.

[0035] Optionally, the heat calculation module includes a heat generation calculation submodule and a cooling calculation submodule;

[0036] The heat generation calculation submodule is used to calculate the heat generation of the target battery during the charging process based on the battery system model;

[0037] The cooling calculation submodule is used to calculate the heat dissipation of the target battery during the charging process based on the battery system model.

[0038] Optionally, the heat generation calculation submodule includes a Joule heat calculation unit, a polarization heat calculation unit, a reaction heat calculation unit and a side reaction heat calculation unit, and the heat generation includes Joule heat, polarization heat, reaction heat and side reaction heat;

[0039] The Joule heat calculation unit is used to determine the Joule heat according to the charge and discharge current of the target battery, the ohmic internal resistance of the pole core of the target battery, and the ohmic internal resistance of the pole tab of the target battery;

[0040] The polarization heat calculation unit is used to determine the polarization heat according to the charge and discharge current of the target battery and the polarization internal resistance of the target battery;

[0041] The reaction heat calculation unit is used to determine the reaction heat according to the amount of the substance that outputs electrons for the target battery during the charge and discharge process, the electromotive force of the target battery and the temperature coefficient of the target battery;

[0042] The side reaction heat calculation unit is used to determine the side reaction heat according to the estimated coefficients of the reaction heat and the side reaction heat, the Joule heat, the polarization heat and the reaction heat.

[0043] Optionally, the cooling calculation submodule includes a convection heat dissipation calculation unit and a contact heat exchange calculation unit, and the heat dissipation includes fluid heat dissipation and solid heat dissipation;

[0044] The fluid heat dissipation calculation unit is used to determine the fluid heat dissipation according to the average temperature difference between the fluid and the solid surface on the heat exchange surface, the convection heat transfer area, the convection heat transfer coefficient and the convection heat transfer amount;

[0045] The contact heat exchange calculation unit is used to determine the solid heat dissipation according to the heat flux density per unit area, thermal conductivity, and heat transfer area.

[0046] Optionally, the calculating the temperature change of the target battery cell based on the heat generation and the heat dissipation includes:

[0047] Determining a heat change amount according to the heat generation and the heat dissipation;

[0048] The temperature variation of the target battery cell is determined according to the heat variation and the battery cell mass of the target battery.

[0049] Optionally, the optimizing the battery cell cooling strategy of the target battery based on the battery cell temperature variation includes:

[0050] Determine the target temperature of the water cooling plate according to the change in the battery cell temperature, the charge and discharge current of the target battery cell, the fluid temperature, and the total resistance value of the battery cell during the charge and discharge process;

[0051] The water cooling plate parameters in the battery cell cooling system are optimized according to the water cooling plate target temperature.

[0052] In a third aspect, an embodiment of the present application provides a computer device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the computer device is running, the processor communicates with the memory through the bus, and when the machine-readable instructions are executed by the processor, the steps of the battery cell cooling strategy optimization method described in any optional implementation manner of the first aspect are performed.

[0053] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, executes the steps of the method for optimizing the battery cell cooling strategy described in any optional implementation manner in the first aspect above.

[0054] The technical solution provided by this application includes but is not limited to the following beneficial effects:

[0055] The present application constructs a battery system model of a target battery through a battery system model construction module, and then calculates the heat generation and heat dissipation of the target battery during the charging process based on the battery system model through a heat calculation module, and calculates the temperature change of the target battery based on the heat generation and heat dissipation through a battery cell temperature calculation module. Finally, the heat calculation module optimizes the battery cell cooling strategy of the target battery based on the temperature change of the battery cell, and can determine the temperature change of the battery cell based on the heat generation and heat dissipation during the battery charging and discharging process, and dynamically adjust and optimize the battery cooling strategy based on the temperature change of the battery cell, thereby ensuring the safety of battery use by cooling the battery, extending the battery life, and improving the endurance and safety of the entire vehicle.

[0056] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0058] Figure 1A flow chart of a method for optimizing a battery core cooling strategy provided by a first embodiment of the present invention is shown;

[0059] Figure 2 A schematic structural diagram of a battery cooling system provided by Embodiment 1 of the present invention is shown;

[0060] Figure 3 A schematic diagram of the structure of a battery system model provided by the first embodiment of the present invention is shown;

[0061] Figure 4 A flow chart of a method for calculating battery charging heat provided by the first embodiment of the present invention is shown;

[0062] Figure 5 A flow chart of a method for calculating heat generation of battery charging provided by the first embodiment of the present invention is shown;

[0063] Figure 6 A flow chart of a method for calculating heat dissipation during battery charging provided by the first embodiment of the present invention is shown;

[0064] Figure 7 A flow chart of a method for calculating a temperature variation of a battery cell provided in the first embodiment of the present invention is shown;

[0065] Figure 8 A flowchart of a specific battery cell cooling strategy optimization method provided by the first embodiment of the present invention is shown;

[0066] Fig. 9 A schematic diagram of the structure of a battery core cooling strategy optimization system provided by the second embodiment of the present invention is shown;

[0067] Fig.10 A schematic diagram showing the structure of a second battery cell cooling strategy optimization system provided by the second embodiment of the present invention is shown;

[0068] Fig.11 A schematic structural diagram of a third battery cell cooling strategy optimization system provided by the second embodiment of the present invention is shown;

[0069] Fig.12 A schematic structural diagram of a fourth battery cell cooling strategy optimization system provided by the second embodiment of the present invention is shown;

[0070] Fig.13 A schematic diagram of the structure of a computer device provided in Embodiment 3 of the present invention is shown. DETAILED DESCRIPTION

[0071] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

[0072] Embodiment 1

[0073] To facilitate understanding of this application, Figure 1 The flowchart of a method for optimizing a battery cell cooling strategy provided by the first embodiment of the present invention is shown to describe the contents of the first embodiment of the present application in detail.

[0074] See also Figure 1 As shown, Figure 1 A flow chart of a cell cooling strategy optimization method provided by the first embodiment of the present invention is shown, wherein the method is applied to a cell cooling strategy optimization system, the system includes a battery system model building module, a heat calculation module and a cell temperature calculation module, and the method includes steps S101 to S104:

[0075] S101: The battery system model building module builds a battery system model of a target battery.

[0076] Specifically, a first-order RC equivalent circuit model is used as the system model of the target battery (lithium-ion battery).

[0077] S102: The heat calculation module calculates the heat generation and heat dissipation of the target battery during the charging process based on the battery system model.

[0078] Specifically, the target battery generates heat (i.e., heat generation) during the charging process, and cooling the battery through the battery cooling system in the target battery will dissipate part of the heat (i.e., heat dissipation). Figure 2 As shown, Figure 2 A structural schematic diagram of a battery cooling system provided in Embodiment 1 of the present invention is shown, wherein the battery cooling system includes a water cooling plate (solid) and air (fluid), and one side of the battery cell of the target battery is in contact with the water cooling plate for solid heat dissipation, and the other side is in contact with the air for fluid heat dissipation.

[0079] S103: The battery cell temperature calculation module calculates a battery cell temperature change of the target battery based on the heat generation and the heat dissipation.

[0080] Specifically, the ideal operating temperature of the battery cell, the initial SOC remaining capacity, the initial battery temperature, the physical characteristics and other parameters are input into the battery cell temperature calculation module, and the battery cell temperature change is calculated based on the parameters and output to the contact heat exchange calculation module.

[0081] S104: The heat calculation module optimizes the battery cell cooling strategy of the target battery based on the battery cell temperature variation.

[0082] Specifically, the heat calculation module optimizes the cell cooling strategy, that is, the temperature of the water cooling plate in the battery cooling system, based on the gap between the predicted cell temperature and the ideal operating temperature (cell temperature change), thereby optimizing the cell cooling strategy.

[0083] In an optional embodiment, the battery system model includes polarization internal resistance, polarization capacitance, pole core ohmic internal resistance, pole tab ohmic internal resistance and simulated power supply, and the polarization internal resistance and the polarization capacitance are connected in parallel and in series with the pole core ohmic internal resistance, the pole tab ohmic internal resistance and the simulated power supply.

[0084] For details, see Figure 3 As shown, Figure 3 The structure diagram of a battery system model provided by the first embodiment of the present invention is shown, wherein the battery system model includes a polarization internal resistance R P , polarization capacitance C P 、Battery core ohmic internal resistance R j 、Battery terminal ohmic internal resistance R o and simulated power supply (open circuit voltage is U ocv ), polarization internal resistance R P and polarization capacitance C P Connected in parallel as a whole, with the battery core ohmic internal resistance R j 、Battery terminal ohmic internal resistance R o Connect in series with the analog power supply, U P is the polarization internal resistance R P The voltage across the two ends (V), I is the battery charge and discharge current (A), U t is the terminal voltage of the battery.

[0085] In an optional embodiment, the heat calculation module includes a heat generation calculation submodule and a cooling calculation submodule, see Figure 4 As shown, Figure 4A flow chart of a battery charging heat calculation method provided in Embodiment 1 of the present invention is shown, wherein the heat calculation module calculates the heat generation and heat dissipation of the target battery during the charging process based on the battery system model, including steps S401 to S402:

[0086] S401: The heat generation calculation submodule calculates the heat generation of the target battery during the charging process based on the battery system model.

[0087] Specifically, the heat generated by the target battery during the charging and discharging process mainly includes Joule heat, polarization heat, reaction heat and side reaction heat, among which Joule heat accounts for the vast majority of the total heat, polarization heat and reaction heat each account for a part of the total heat, and side reaction heat accounts for a smaller part of the total heat.

[0088] S402: The cooling calculation submodule calculates the heat dissipation of the target battery during the charging process based on the battery system model.

[0089] Specifically, the heat dissipated by the target battery through the battery cooling system during the charging and discharging process mainly includes the heat dissipated through the water cooling plate and the heat dissipated through the air.

[0090] In an optional embodiment, the heat generation calculation submodule includes a Joule heat calculation unit, a polarization heat calculation unit, a reaction heat calculation unit and a side reaction heat calculation unit, and the heat generation includes Joule heat, polarization heat, reaction heat and side reaction heat.

[0091] Specifically, Joule heat is the heat generated when current flows through the conductive medium inside the lithium-ion battery during the charging and discharging process.

[0092] Polarization heat refers to the polarization phenomenon that occurs on the surface of the battery electrode during the charge and discharge process of lithium-ion batteries. The heat generated by the polarization phenomenon of the battery is called polarization heat. The current treatment for polarization heat is to replace the polarization heat with the Joule heat generated by the polarization internal resistance of the battery.

[0093] Reaction heat is the heat generated by the electrochemical reaction of lithium ions in the process of embedding and de-embedding on the positive and negative electrodes during the charging and discharging process of lithium-ion batteries. During the charging process, lithium ions are de-embedded from the positive plate and embedded in the negative plate through the electrolyte, absorbing heat; during the discharging process, lithium ions are de-embedded from the negative plate and embedded in the positive plate through the electrolyte, releasing heat. Therefore, for lithium-ion batteries, the reaction heat is generally negative (absorbent) during charging and positive (exothermic) during discharging.

[0094] The side reaction heat is the side reaction heat generated by lithium-ion batteries during the charging and discharging process. It mainly includes the heat generated by the decomposition of electrode materials due to the self-discharge of the battery and the heat generated by the decomposition of the electrolyte at high temperature. The reaction heat and side reaction heat account for a small proportion of the total heat and can be estimated based on experience.

[0095] See also Figure 5 As shown, Figure 5 A flow chart of a method for calculating the heat generation of a battery during charging provided by the first embodiment of the present invention is shown, wherein the heat generation calculation submodule calculates the heat generation of the target battery during the charging process based on the battery system model, including steps S501 to S504:

[0096] S501: The Joule heat calculation unit determines the Joule heat according to the charge and discharge current of the target battery, the ohmic internal resistance of the core of the target battery, and the ohmic internal resistance of the tab of the target battery.

[0097] Specifically, the Joule heat Q is determined by the following expression: j :

[0098] Q j =I 2 ×(R j +R o );

[0099] Where, I is the charge and discharge current of the target battery (A); R j is the ohmic internal resistance of the target battery core (Ω); R o is the ohmic internal resistance (Ω) of the target battery’s tab. The ohmic internal resistance is mainly composed of the resistance of the positive and negative electrode materials, electrolyte, diaphragm, etc.

[0100] S502: The polarization heat calculation unit determines the polarization heat according to the charge and discharge current of the target battery and the polarization internal resistance of the target battery.

[0101] Specifically, the polarization heat Q is determined by the following expression: p :

[0102] Q p =I 2 ×R p ;

[0103] Where, I is the charge and discharge current of the target battery (A), R p is the polarization internal resistance of the battery (Ω).

[0104] S503: The reaction heat calculation unit determines the reaction heat according to the amount of the substance that outputs electrons for the target battery during the charge and discharge process, the electromotive force of the target battery, and the temperature coefficient of the target battery.

[0105] Specifically, the reaction heat Q is determined by the following expression: r :

[0106]

[0107] Among them, n is the amount of substance (mol) that the target battery outputs electrons during the charge and discharge process; E is the electromotive force of the battery (V); F is the Faraday constant, which is the absolute value of the charge carried by 1 mol of electrons, and its value is approximately 96484.5 (C / mol). is the temperature coefficient of the battery. When the temperature coefficient is positive, it indicates that the battery absorbs heat from the environment, and a negative value indicates that the battery releases heat.

[0108] S504: The side reaction heat calculation unit determines the side reaction heat according to the reaction heat and the estimated coefficient of the side reaction heat, the Joule heat, the polarization heat, and the reaction heat.

[0109] Specifically, the side reaction heat Q is determined by the following expression: s :

[0110] Q s =K(Q j +Q p +Q r );

[0111] Among them, K is the estimated coefficient of reaction heat and side reaction heat, which needs to be determined based on battery characteristics and design experience. Considering that the voltage platform of ternary cells is higher than that of iron-lithium cells, and the reaction process involves Mn dissolution, it is easier to produce defects in electrode materials compared to iron-lithium cells, so the general value of ternary cells is 0.003~0.006; the value of iron-lithium cells is 0.001~0.003.

[0112] In an optional embodiment, the cooling calculation submodule includes a convection heat dissipation calculation unit and a contact heat exchange calculation unit, and the heat dissipation includes fluid heat dissipation and solid heat dissipation; see Figure 6 As shown, Figure 6 A flowchart of a method for calculating heat dissipation during battery charging provided by the first embodiment of the present invention is shown, wherein the cooling calculation submodule calculates the heat dissipation of the target battery during charging based on the battery system model, including steps S601 to S602:

[0113] S601: The fluid heat dissipation calculation unit determines the fluid heat dissipation according to the average temperature difference between the fluid and the solid surface on the heat exchange surface, the convection heat transfer area, the convection heat transfer coefficient and the convection heat transfer amount.

[0114] Specifically, the fluid heat dissipation φ is determined by the following expression:

[0115] φ=ShΔT m ;

[0116] Where, ΔT m is the average temperature difference between the fluid and the solid surface on the heat transfer surface; S is the convective heat transfer area; h is the convective heat transfer coefficient.

[0117] S602: The contact heat exchange calculation unit determines the solid heat dissipation according to the heat flux density per unit area, thermal conductivity, and heat transfer area.

[0118] Specifically, the heat dissipation q of the fluid is determined by the following expression:

[0119] q = kAΔT / L;

[0120] Where q is the heat flux per unit area; k is the thermal conductivity; A represents the heat transfer area; ΔT is the temperature difference, ΔT = T s -T d , T s is the water cooling plate temperature, T d is the battery cell temperature; L is the distance between the water cooling plate and the battery cell.

[0121] In an alternative embodiment, see Figure 7 As shown, Figure 7 A flow chart of a method for calculating a battery cell temperature variation provided by the first embodiment of the present invention is shown, wherein the method for calculating the battery cell temperature variation of the target battery based on the heat generation and the heat dissipation comprises steps S701 to S702:

[0122] S701: Determine a heat change amount according to the heat generation and the heat dissipation.

[0123] Specifically, the heat change ΔQ is determined by the following expression:

[0124] ΔQ=Q s +Q j +Q p +Q r +φ+q;

[0125] Among them, Q j is the joule heat, Q p is the polarization heat, Q r is the heat of reaction, Q s is the side reaction heat, φ is the heat dissipated by the fluid, and q is the heat dissipated by the fluid.

[0126] S702: Determine a temperature variation of a battery cell of the target battery according to the heat variation and the battery cell mass of the target battery.

[0127] Specifically, the cell temperature change ΔT is determined by the following expression:

[0128] ΔT = ΔQ / cm;

[0129] Among them, ΔQ is the heat change, c is the specific heat capacity of the target battery cell (the heat capacity range of lithium-ion batteries is generally between 800 and 1200 J / kgK, NMC cells are 1040 J / kgK, and LFP cells are 1145 J / kgK); m is the cell mass of the target battery.

[0130] In an alternative embodiment, see Figure 8 As shown, Figure 8 A flowchart of a specific method for optimizing a battery cell cooling strategy provided by the first embodiment of the present invention is shown, wherein the method for optimizing the battery cell cooling strategy of the target battery based on the battery cell temperature variation comprises steps S801 to S802:

[0131] S801: Determine a target temperature of the water cooling plate according to the temperature change of the battery cell, the charge and discharge current of the target battery cell, the fluid temperature, and the total resistance value of the battery cell during the charge and discharge process.

[0132] Specifically, the target temperature T of the water cooling plate is determined by the following expression: c :

[0133] T c =k1x 2 z+k1y+k3ΔT;

[0134] Among them, k1 is the first preset coefficient, k2 is the second preset coefficient, k3 is the third preset coefficient, x is the charge and discharge current of the target battery, y is the fluid (gas) temperature, and z is the total resistance value of the battery during the charge and discharge process. The values ​​of k1, k2, and k3 are related to parameters such as battery cell mass and battery cell thermal properties.

[0135] S802: Optimizing the parameters of the water cooling plate in the battery cell cooling system according to the target temperature of the water cooling plate.

[0136] Specifically, the temperature of the water cooling plate in the cell cooling system of the target battery is adjusted to the target temperature of the water cooling plate, and the parameters of the water cooling plate are optimized to achieve optimization of the battery cooling strategy.

[0137] In addition, the battery cell cooling strategy optimization system also includes a charge and discharge control module and a temperature output module. The charge and discharge control module controls the charge and discharge mode, such as constant current charge and discharge, constant voltage charge and discharge, constant power charge and discharge, etc. The temperature output module inputs the battery cell temperature change output by the battery cell temperature calculation module into the heat calculation module.

[0138] Embodiment 2

[0139] See also Fig. 9As shown, Fig. 9 The schematic diagram of the structure of a battery cell cooling strategy optimization system provided by the second embodiment of the present invention is shown, wherein the system includes a battery system model building module 901, a heat calculation module 902 and a battery cell temperature calculation module 903:

[0140] The battery system model building module is used to build a battery system model of a target battery;

[0141] The heat calculation module is used to calculate the heat generation and heat dissipation of the target battery during the charging process based on the battery system model;

[0142] The battery cell temperature calculation module is used to calculate the battery cell temperature change of the target battery based on the heat generation and the heat dissipation;

[0143] The heat calculation module is used to optimize the battery cell cooling strategy of the target battery based on the battery cell temperature change.

[0144] In an optional embodiment, the battery system model includes polarization internal resistance, polarization capacitance, pole core ohmic internal resistance, pole tab ohmic internal resistance and simulated power supply, and the polarization internal resistance and the polarization capacitance are connected in parallel and in series with the pole core ohmic internal resistance, the pole tab ohmic internal resistance and the simulated power supply.

[0145] In an alternative embodiment, see Fig.10 As shown, Fig.10 The schematic diagram of the structure of the second battery cell cooling strategy optimization system provided by the second embodiment of the present invention is shown, wherein the heat calculation module 902 includes a heat generation calculation submodule 9021 and a cooling calculation submodule 9022;

[0146] The heat generation calculation submodule is used to calculate the heat generation of the target battery during the charging process based on the battery system model;

[0147] The cooling calculation submodule is used to calculate the heat dissipation of the target battery during the charging process based on the battery system model.

[0148] In an alternative embodiment, see Fig.11 As shown, Fig.11 The schematic diagram of the structure of the third battery cell cooling strategy optimization system provided in the second embodiment of the present invention is shown, wherein the heat generation calculation submodule 9021 includes a Joule heat calculation unit 90211, a polarization heat calculation unit 90212, a reaction heat calculation unit 90213 and a side reaction heat calculation unit 90214, and the heat generation includes Joule heat, polarization heat, reaction heat and side reaction heat;

[0149] The Joule heat calculation unit is used to determine the Joule heat according to the charge and discharge current of the target battery, the ohmic internal resistance of the pole core of the target battery, and the ohmic internal resistance of the pole tab of the target battery;

[0150] The polarization heat calculation unit is used to determine the polarization heat according to the charge and discharge current of the target battery and the polarization internal resistance of the target battery;

[0151] The reaction heat calculation unit is used to determine the reaction heat according to the amount of the substance that outputs electrons for the target battery during the charge and discharge process, the electromotive force of the target battery and the temperature coefficient of the target battery;

[0152] The side reaction heat calculation unit is used to determine the side reaction heat according to the estimated coefficients of the reaction heat and the side reaction heat, the Joule heat, the polarization heat and the reaction heat.

[0153] In an alternative embodiment, see Fig.12 As shown, Fig.12 The schematic diagram of the structure of the fourth battery cell cooling strategy optimization system provided in the second embodiment of the present invention is shown, wherein the cooling calculation submodule 9022 includes a convection heat dissipation calculation unit 90221 and a contact heat exchange calculation unit 90222, and the heat dissipation includes fluid heat dissipation and solid heat dissipation;

[0154] The fluid heat dissipation calculation unit is used to determine the fluid heat dissipation according to the average temperature difference between the fluid and the solid surface on the heat exchange surface, the convection heat transfer area, the convection heat transfer coefficient and the convection heat transfer amount;

[0155] The contact heat exchange calculation unit is used to determine the solid heat dissipation according to the heat flux density per unit area, thermal conductivity, and heat transfer area.

[0156] In an optional implementation, the calculating the temperature change of the target battery cell based on the heat generation and the heat dissipation includes:

[0157] Determining a heat change amount according to the heat generation and the heat dissipation;

[0158] The temperature variation of the target battery cell is determined according to the heat variation and the battery cell mass of the target battery.

[0159] In an optional implementation, the optimizing the battery cell cooling strategy of the target battery based on the battery cell temperature variation includes:

[0160] Determine the target temperature of the water cooling plate according to the change in the battery cell temperature, the charge and discharge current of the target battery cell, the fluid temperature, and the total resistance value of the battery cell during the charge and discharge process;

[0161] The water cooling plate parameters in the battery cell cooling system are optimized according to the water cooling plate target temperature.

[0162] Embodiment 3

[0163] Based on the same application concept, see Fig.13 As shown, Fig.13 FIG. 4 shows a schematic diagram of the structure of a computer device provided by Embodiment 3 of the present invention, wherein: Fig.13 As shown, a computer device 1300 provided in Embodiment 3 of the present application includes:

[0164] A processor 1301, a memory 1302 and a bus 1303, wherein the memory 1302 stores machine-readable instructions executable by the processor 1301. When the computer device 1300 is running, the processor 1301 communicates with the memory 1302 via the bus 1303. When the processor 1301 is running, the machine-readable instructions execute the steps of the battery cell cooling strategy optimization method shown in the above-mentioned embodiment 1.

[0165] Embodiment 4

[0166] Based on the same application concept, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the battery cell cooling strategy optimization method described in any one of the above embodiments are executed.

[0167] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0168] The computer program product for optimizing the cell cooling strategy provided in the embodiment of the present invention includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the method described in the previous method embodiment. The specific implementation can be found in the method embodiment and will not be repeated here.

[0169] The battery cell cooling strategy optimization system provided in the embodiment of the present invention can be specific hardware on the device or software or firmware installed on the device. The system provided in the embodiment of the present invention has the same implementation principle and technical effects as the aforementioned method embodiment. For the sake of brief description, for matters not mentioned in the system embodiment, reference can be made to the corresponding contents in the aforementioned method embodiment. Technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices and units described above can all refer to the corresponding processes in the aforementioned method embodiment, and will not be repeated here.

[0170] In the embodiments provided by the present invention, it should be understood that the disclosed systems and methods can be implemented in other ways. The system embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some communication interface, device or unit, which can be electrical, mechanical or other forms.

[0171] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0172] In addition, each functional unit in the embodiment provided by the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0173] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0174] It should be noted that similar numbers and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and are not to be understood as indicating or implying relative importance.

[0175] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can still modify the technical solutions described in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. They should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for optimizing a battery cell cooling strategy, characterized in that: Applied to a battery cell cooling strategy optimization system, the system includes a battery system model building module, a heat calculation module and a battery cell temperature calculation module, and the method includes: The battery system model building module builds a battery system model of a target battery; The heat calculation module calculates the heat generation and heat dissipation of the target battery during the charging process based on the battery system model; The battery cell temperature calculation module calculates the battery cell temperature change of the target battery based on the heat generation and the heat dissipation; The heat calculation module optimizes the battery cell cooling strategy of the target battery based on the battery cell temperature variation.

2. The method according to claim 1, characterized in that The battery system model includes polarization internal resistance, polarization capacitance, pole core ohmic internal resistance, pole tab ohmic internal resistance and simulated power supply. The polarization internal resistance and the polarization capacitance are connected in parallel, and are connected in series with the pole core ohmic internal resistance, the pole tab ohmic internal resistance and the simulated power supply.

3. The method according to claim 1, characterized in that The heat calculation module includes a heat generation calculation submodule and a cooling calculation submodule. The heat calculation module calculates the heat generation and heat dissipation of the target battery during the charging process based on the battery system model, including: The heat generation calculation submodule calculates the heat generation of the target battery during the charging process based on the battery system model; The cooling calculation submodule calculates the heat dissipation of the target battery during the charging process based on the battery system model.

4. The method according to claim 3, characterized in that The heat generation calculation submodule includes a Joule heat calculation unit, a polarization heat calculation unit, a reaction heat calculation unit and a side reaction heat calculation unit, and the heat generation includes Joule heat, polarization heat, reaction heat and side reaction heat; The heat generation calculation submodule calculates the heat generation of the target battery during the charging process based on the battery system model, including: The Joule heat calculation unit determines the Joule heat according to the charge and discharge current of the target battery, the ohmic internal resistance of the pole core of the target battery, and the ohmic internal resistance of the pole tab of the target battery; The polarization heat calculation unit determines the polarization heat according to the charge and discharge current of the target battery and the polarization internal resistance of the target battery; The reaction heat calculation unit determines the reaction heat according to the amount of a substance that outputs electrons for the target battery during charge and discharge, the electromotive force of the target battery, and the temperature coefficient of the target battery; The side reaction heat calculation unit determines the side reaction heat based on the estimated coefficients of reaction heat and side reaction heat, the Joule heat, the polarization heat, and the reaction heat.

5. The method according to claim 3, characterized in that: The cooling calculation submodule includes a convection heat dissipation calculation unit and a contact heat exchange calculation unit, and the heat dissipation includes fluid heat dissipation and solid heat dissipation; The cooling calculation submodule calculates the heat dissipation of the target battery during the charging process based on the battery system model, including: The fluid heat dissipation calculation unit determines the fluid heat dissipation according to the average temperature difference between the fluid and the solid surface on the heat exchange surface, the convection heat transfer area, the convection heat transfer coefficient and the convection heat transfer amount; The contact heat exchange calculation unit determines the solid heat dissipation according to the heat flux density per unit area, the thermal conductivity, and the heat transfer area.

6. The method according to claim 1, characterized in that The calculating the temperature change of the target battery cell based on the heat generation and the heat dissipation includes: Determining a heat change amount according to the heat generation and the heat dissipation; The temperature variation of the target battery cell is determined according to the heat variation and the battery cell mass of the target battery.

7. The method according to claim 1, characterized in that The optimizing the battery cell cooling strategy of the target battery based on the battery cell temperature variation includes: Determine the target temperature of the water cooling plate according to the change in the battery cell temperature, the charge and discharge current of the target battery cell, the fluid temperature, and the total resistance value of the battery cell during the charge and discharge process; The water cooling plate parameters in the battery cell cooling system are optimized according to the water cooling plate target temperature.

8. A battery cell cooling strategy optimization system, characterized in that: The system includes a battery system model building module, a heat calculation module and a battery cell temperature calculation module; The battery system model building module is used to build a battery system model of a target battery; The heat calculation module is used to calculate the heat generation and heat dissipation of the target battery during the charging process based on the battery system model; The battery cell temperature calculation module is used to calculate the battery cell temperature change of the target battery based on the heat generation and the heat dissipation; The heat calculation module is used to optimize the battery cell cooling strategy of the target battery based on the battery cell temperature change.

9. A computer device, characterized in that: include: A processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the computer device is running, the processor and the memory communicate via the bus, and when the machine-readable instructions are executed by the processor, the steps of the method for optimizing the battery cell cooling strategy as described in any one of claims 1 to 7 are performed.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the battery cell cooling strategy optimization method as described in any one of claims 1 to 7 are executed.

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