Battery discharge performance determination method and device, electronic equipment and storage medium

Abstract

The invention discloses a battery discharge performance determination method and device, electronic equipment and a storage medium. The battery discharge performance determination method comprises the following steps: obtaining discharge temperature information, battery design parameters, battery state information and current working condition information of a target battery; determining reaction coefficient information of the target battery according to the discharge temperature information, the battery design parameters, the battery state information and the current working condition information; wherein the reaction coefficient information comprises a positive electrode diffusion coefficient, a negative electrode diffusion coefficient, a liquid phase diffusion coefficient, a positive electrode interface reaction rate and a negative electrode interface reaction rate; and determining discharge voltage information of the target battery according to the discharge temperature information, the battery design parameters, the reaction coefficient information and the battery electrochemical reaction mechanism equation. According to the invention, the discharge effect of the target battery can be evaluated quickly, the test cost is saved, and the development efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a method, device, electronic device and storage medium for determining battery discharge performance. Background Art

[0002] With the rapid development of the new energy industry, high-performance new energy vehicle models have increasingly higher requirements for the discharge capacity of power batteries and high-power batteries.

[0003] In the existing technology, most major battery companies in the industry use simulation combined with testing to evaluate battery discharge performance. Therefore, a large amount of test and simulation data support is required to meet different customer requirements. The performance evaluation of batteries is slow and requires a lot of manpower and material resources. Summary of the invention

[0004] The present invention provides a method, device, electronic device and storage medium for determining battery discharge performance, so as to realize rapid evaluation of the discharge effect of a target battery, save test costs and improve development efficiency.

[0005] According to one aspect of the present invention, a method for determining battery discharge performance is provided, the method comprising:

[0006] Obtain the discharge temperature information, battery design parameters, battery status information and current operating condition information of the target battery; wherein the battery design parameters include the number of positive electrode layers, positive electrode length, negative electrode length, positive electrode width, negative electrode width, positive electrode surface density, negative electrode surface density, positive electrode compaction density, negative electrode compaction density, positive electrode gram capacity and negative electrode gram capacity; the battery status information includes the ambient temperature, the initial state of charge of the battery and the operating time; the current operating condition information includes the corresponding relationship between the output current and the operating time; the discharge temperature information is the real-time temperature of the target battery during the discharge process;

[0007] Determine the reaction coefficient information of the target battery according to the discharge temperature information, the battery design parameters, the battery state information and the current operating condition information; wherein the reaction coefficient information includes the positive electrode diffusion coefficient, the negative electrode diffusion coefficient, the liquid phase diffusion coefficient, the positive electrode interface reaction rate and the negative electrode interface reaction rate;

[0008] The discharge voltage information of the target battery is determined according to the discharge temperature information, battery design parameters, reaction coefficient information and battery electrochemical reaction mechanism equation.

[0009] Furthermore, the method for determining the discharge temperature information of the target battery is as follows:

[0010] Determine the discharge temperature information of the target battery according to the electrode solid phase conductivity equation, the electrolyte liquid phase conductivity equation, the electrochemical reaction heat generation equation, the Ohm heat generation equation and the polarization heat generation equation;

[0011] Among them, the heat generation equation of the electrochemical reaction is:

[0012]

[0013] Among them, q r is the heat generated by the electrochemical reaction, A is the first constant, L is the thickness of the electrode, j is the reaction current density, is the solid phase potential, is the liquid phase potential, U is the voltage of the target battery;

[0014] Ohm's heat generation equation is:

[0015]

[0016] Among them, q j is Ohmic heat, σ eff is the electronic conductivity, k eff is the solid phase ionic conductivity, is the electrolyte ion conductivity, C e is the electrolyte concentration;

[0017] The polarization heat generation equation is:

[0018]

[0019] Among them, q c is polarization heat, I is operating current, and R1 is AC resistance;

[0020] Electrode solid phase conductivity equation:

[0021]

[0022] in, is the partial derivative of x in three-dimensional coordinates, J is the volume current density;

[0023] Electrolyte liquid phase conductivity equation:

[0024]

[0025] Among them, i l is the ion current density, F is the Faraday constant, is the number of effective transfers.

[0026] Furthermore, the cathode diffusion coefficient is determined by the following formula:

[0027] Ds_pos=(Ds_pos_i / ((1+soc-0.05) 1.6 ))*e -(35 / R)*(T-1 / Tr) ;

[0028] Wherein, Ds_pos is the positive electrode diffusion coefficient, Ds_pos_i is the positive electrode initial diffusion coefficient, soc is the initial state of charge of the battery, R2 is the second constant, T is the discharge temperature of the target battery, and Tr is the ambient temperature;

[0029] The cathode diffusion coefficient is determined by the following formula:

[0030] Ds_neg=Ds_neg_i*exp -(35 / R)*(T-1 / Tr) ;

[0031] Among them, Ds_neg is the diffusion coefficient of the negative electrode, and Ds_pos_i is the initial diffusion coefficient of the negative electrode;

[0032] The liquid phase diffusion coefficient is determined by the following formula:

[0033] D L =0.33*(1*10 -4 *10 -4.43-(54 / (T-229-0.05*C) -2.2*10 -4*C );

[0034] Among them, D L is the liquid phase diffusion coefficient, C is the charge and discharge rate;

[0035] The cathode interface reaction rate is determined by the following formula:

[0036] k_pos=k_pos_i*e 0.5*(soc-0.05) *e -(15 / R)*(T-1 / Tr) ;

[0037] Among them, k_pos is the cathode interface reaction rate, k_pos_i is the cathode interface initial reaction rate;

[0038] The negative electrode interface reaction rate is determined by the following formula:

[0039] k_neg=k_neg_i*e 1*(soc) *e -(10 / R)*(T-1 / Tr) ;

[0040] Among them, k_neg is the negative electrode interface reaction rate, and k_neg_i is the negative electrode interface initial reaction rate.

[0041] Further, the discharge voltage information of the target battery is determined according to the discharge temperature information, battery design parameters, reaction coefficient information and battery electrochemical reaction mechanism equation, including:

[0042] Determine battery capacity information, electrode thickness information and position coordinate information according to battery design parameters;

[0043] The discharge voltage information of the target battery is determined according to the battery capacity information, electrode thickness information, position coordinate information, discharge temperature information, reaction coefficient information and battery electrochemical reaction mechanism equation.

[0044] Furthermore, the battery electrochemical reaction mechanism equation includes:

[0045] Fick's second law equation:

[0046]

[0047] Among them, C S is the solid phase lithium ion concentration, r is the lithium ion radius, t is the operating time, D S is the solid phase diffusion coefficient;

[0048] Planck equation:

[0049]

[0050] Where C is the liquid phase lithium ion concentration, D L is the liquid phase diffusion coefficient, i l is the ion current density, F is the Faraday constant, is the effective transfer number, j is the reaction current density, To find the partial derivative of z in three-dimensional coordinates;

[0051] Electrode process kinetic equation:

[0052]

[0053] Where i0 is the exchange current density, α a is the anode transfer coefficient, η s is the overpotential, R is the gas constant, T is the battery temperature of the target battery, α c is the cathode transfer coefficient;

[0054] Exchange current density calculation equation:

[0055]

[0056] Among them, k c is the cathode interface reaction rate, k a is the anode interface reaction rate, C s,max is the maximum ion concentration, is the surface ion concentration, C e is the electrolyte concentration.

[0057] Further, the discharge voltage information of the target battery is determined according to the discharge temperature information, the battery design parameters, the reaction coefficient information and the battery electrochemical reaction mechanism equation, and then also includes:

[0058] A voltage-time curve is determined according to voltage information of the target battery, and a temperature-time curve is determined according to temperature information of the target battery.

[0059] According to another aspect of the present invention, a battery discharge performance determination device is provided, the battery discharge performance determination device comprising:

[0060] A parameter acquisition module is used to obtain the discharge temperature information, battery design parameters, battery status information and current operating condition information of the target battery; wherein the battery design parameters include the number of positive electrode layers, positive electrode length, negative electrode length, positive electrode width, negative electrode width, positive electrode surface density, negative electrode surface density, positive electrode compaction density, negative electrode compaction density, positive electrode gram capacity and negative electrode gram capacity; the battery status information includes the ambient temperature, the initial state of charge of the battery and the operating time; the current operating condition information includes the corresponding relationship between the output current and the operating time; the discharge temperature information is the real-time temperature of the target battery during the discharge process;

[0061] A reaction coefficient determination module is used to determine the reaction coefficient information of the target battery according to the discharge temperature information, the battery design parameters, the battery state information and the current operating condition information; wherein the reaction coefficient information includes the positive electrode diffusion coefficient, the negative electrode diffusion coefficient, the liquid phase diffusion coefficient, the positive electrode interface reaction rate and the negative electrode interface reaction rate;

[0062] The discharge voltage determination module is used to determine the discharge voltage information of the target battery according to the discharge temperature information, battery design parameters, reaction coefficient information and battery electrochemical reaction mechanism equation.

[0063] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0064] at least one processor; and

[0065] a memory communicatively connected to the at least one processor; wherein,

[0066] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the battery discharge performance determination method described in any embodiment of the present invention.

[0067] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the battery discharge performance determination method described in any embodiment of the present invention when executed.

[0068] According to another aspect of the present invention, a computer program product is provided. The computer program product comprises a computer program. When the computer program is executed by a processor, the computer program is used to implement the method for determining battery discharge performance according to any embodiment of the present invention.

[0069] The battery discharge performance determination method of the embodiment of the present invention obtains the discharge temperature information, battery design parameters, battery status information and current operating condition information of the target battery, and determines the reaction coefficient information of the target battery according to the discharge temperature information, battery design parameters, battery status information and current operating condition information, and finally determines the discharge voltage information of the target battery according to the discharge temperature information, battery design parameters, reaction coefficient information and battery electrochemical reaction mechanism equation, so that the user can quickly evaluate the discharge effect of the target battery according to the design parameters, battery status information and current operating condition information of the target battery, thereby saving test costs and improving development efficiency.

[0070] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0072] Figure 1 is a flow chart of a method for determining battery discharge performance provided by an embodiment of the present invention;

[0073] Figure 2 is a schematic structural diagram of a device for determining battery discharge performance provided by an embodiment of the present invention;

[0074] Figure 3 A schematic diagram of an interface display of a device for determining battery discharge performance according to an embodiment of the present invention;

[0075] Figure 4 A schematic diagram of a current operating condition provided according to an embodiment of the present invention;

[0076] Figure 5 A schematic diagram of the structure of an electronic device that can be used to implement an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0077] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme 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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0078] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0079] The embodiment of the present invention provides a method for determining battery discharge performance. Figure 1 is a flow chart of a method for determining battery discharge performance according to an embodiment of the present invention, referring to Figure 1 , the battery discharge performance determination method includes:

[0080] S110. Obtain the discharge temperature information, battery design parameters, battery status information and current operating condition information of the target battery; wherein the battery design parameters include the number of positive electrode layers, positive electrode length, negative electrode length, positive electrode width, negative electrode width, positive electrode surface density, negative electrode surface density, positive electrode compaction density, negative electrode compaction density, positive electrode gram capacity and negative electrode gram capacity; the battery status information includes the ambient temperature, the initial state of charge of the battery and the operating time; the current operating condition information includes the corresponding relationship between the output current and the operating time; the discharge temperature information is the real-time temperature of the target battery during the discharge process.

[0081] Specifically, the discharge temperature information of the target battery can be determined according to the electrode solid phase conductivity equation, the electrolyte liquid phase conductivity equation, the electrochemical reaction heat generation equation, the Ohm heat generation equation and the polarization heat generation equation. The battery design parameters, battery status information and current operating condition information can be set according to the design requirements of the target battery, and the embodiments of the present invention are not limited to this.

[0082] S120. Determine the reaction coefficient information of the target battery according to the discharge temperature information, the battery design parameters, the battery state information and the current operating condition information; wherein the reaction coefficient information includes the positive electrode diffusion coefficient, the negative electrode diffusion coefficient, the liquid phase diffusion coefficient, the positive electrode interface reaction rate and the negative electrode interface reaction rate.

[0083] Specifically, the positive electrode diffusion coefficient and the negative electrode diffusion coefficient can be determined according to the discharge temperature information, the initial state of charge of the battery in the battery status information, and the ambient temperature; the battery capacity information is determined according to the positive electrode width, negative electrode width, positive electrode surface density, negative electrode surface density, positive electrode compaction density, and negative electrode compaction density in the battery design parameters, and the charge and discharge rate is determined according to the electrode capacity and current operating condition information, and finally the liquid phase diffusion coefficient is determined according to the charge and discharge rate and the discharge temperature information; at the same time, the positive electrode interface reaction rate and the negative electrode interface reaction rate can be determined according to the discharge temperature information, the initial state of charge of the battery in the battery status information, and the ambient temperature.

[0084] S130, determining the discharge voltage information of the target battery according to the discharge temperature information, the battery design parameters, the reaction coefficient information and the battery electrochemical reaction mechanism equation.

[0085] Specifically, the battery capacity information, electrode thickness information and position coordinate information can be determined according to the battery design parameters, and the discharge voltage information of the target battery can be determined according to the battery capacity information, electrode thickness information, position coordinate information, discharge temperature information, reaction coefficient information and battery electrochemical reaction mechanism equation, wherein the discharge voltage information includes multiple groups of discharge voltages. Exemplarily, the discharge voltage information of the target battery can be converted into a voltage-time curve so that the user can intuitively determine the discharge effect of the target battery.

[0086] The battery discharge performance determination method of the embodiment of the present invention obtains the discharge temperature information, battery design parameters, battery status information and current operating condition information of the target battery, and determines the reaction coefficient information of the target battery according to the discharge temperature information, battery design parameters, battery status information and current operating condition information, and finally determines the discharge voltage information of the target battery according to the discharge temperature information, battery design parameters, reaction coefficient information and battery electrochemical reaction mechanism equation, so that the user can quickly evaluate the discharge effect of the target battery according to the design parameters, battery status information and current operating condition information of the target battery, thereby saving test costs and improving development efficiency.

[0087] Furthermore, the method for determining the discharge temperature information of the target battery is as follows:

[0088] Determine the discharge temperature information of the target battery according to the electrode solid phase conductivity equation, the electrolyte liquid phase conductivity equation, the electrochemical reaction heat generation equation, the Ohm heat generation equation and the polarization heat generation equation;

[0089] Among them, the heat generation equation of the electrochemical reaction is:

[0090]

[0091] Among them, q r is the heat generated by the electrochemical reaction, A is the first constant, L is the thickness of the electrode, j is the reaction current density, is the solid phase potential, is the liquid phase potential, U is the voltage of the target battery;

[0092] Ohm's heat generation equation is:

[0093]

[0094] Among them, q j is ohmic heat, σ eff is the electronic conductivity, k eff is the solid phase ionic conductivity, is the electrolyte ion conductivity, C e is the electrolyte concentration;

[0095] The polarization heat generation equation is:

[0096]

[0097] Among them, q c is polarization heat, I is operating current, and R1 is AC resistance;

[0098] Electrode solid phase conductivity equation:

[0099]

[0100] in, is the partial derivative of x in three-dimensional coordinates, J is the volume current density;

[0101] Electrolyte liquid phase conductivity equation:

[0102]

[0103] Among them, i l is the ion current density, F is the Faraday constant, is the number of valid transfers.

[0104] Among them, the electrode sheet thickness L includes the thickness of the positive electrode sheet and the thickness of the negative electrode sheet, and the heat generated by the electrochemical reaction in the positive electrode sheet and the heat generated by the electrochemical reaction in the negative electrode sheet are calculated respectively, and the heat generated by the ohmic heating effect of the positive electrode sheet and the heat generated by the ohmic heating effect of the negative electrode sheet are calculated at the same time.

[0105] Specifically, the heat generated by the electrochemical reaction q can be calculated based on the electrode solid phase conductivity equation, the electrolyte liquid phase conductivity equation, the electrochemical reaction heat generation equation, the Ohm heat generation equation and the polarization heat generation equation. r , Ohm heat q j and polarization heat q c . And according to q r ,q j and q c The real-time temperature change during the battery operation is determined, and then the discharge temperature information of the target battery, that is, the real-time discharge temperature of the target battery, is determined according to the real-time temperature change during the battery operation and the ambient temperature. j It can be understood that the polarization heat q is the heat generated by the ohmic heating effect in the target battery. c It can be understood as the heat generated by the polarization phenomenon caused by the action of current on the positive and negative electrodes during the discharge process of the battery.

[0106] Exemplarily, the discharge temperature of the target battery at the current moment can be determined based on the discharge voltage information at the current moment, and then the calculated discharge temperature at the current moment is substituted into the reaction coefficient information and the battery electrochemical reaction mechanism equation to calculate the discharge voltage information at the next moment, and the discharge voltage information at the next moment is substituted into the electrode solid phase conductivity equation, the electrolyte liquid phase conductivity equation, the electrochemical reaction heat generation equation and the Ohm heat generation equation to calculate the discharge temperature at the next moment, thereby coupling the discharge temperature change of the target battery into the calculation process of the discharge voltage, and also coupling the discharge voltage information into the calculation of the discharge temperature of the target battery, thereby allowing the user to evaluate simultaneously based on the discharge temperature information and the discharge voltage information of the target battery, thereby improving the accuracy of the evaluation. Among them, the discharge voltage information may include solid phase potential, liquid phase potential, voltage of the target battery, etc.

[0107] Furthermore, the cathode diffusion coefficient is determined by the following formula:

[0108] Ds_pos=(Ds_pos_i / ((1+soc-0.05) 1.6 ))*e -(35 / R)*(T-1 / Tr) ;

[0109] Wherein, Ds_pos is the positive electrode diffusion coefficient, Ds_pos_i is the positive electrode initial diffusion coefficient, soc is the initial state of charge of the battery, R2 is the second constant, T is the discharge temperature of the target battery, and Tr is the ambient temperature;

[0110] The cathode diffusion coefficient is determined by the following formula:

[0111] Ds_neg=Ds_neg_i*exp -(35 / R)*(T-1 / Tr) ;

[0112] Among them, Ds_neg is the diffusion coefficient of the negative electrode, and Ds_pos_i is the initial diffusion coefficient of the negative electrode;

[0113] The liquid phase diffusion coefficient is determined by the following formula:

[0114] D L =0.33*(1*10 -4 *10 -4.43-(54 / (T-229-0.05*C) -2.2*10 -4*C );

[0115] Among them, D L is the liquid phase diffusion coefficient, C is the charge and discharge rate;

[0116] The cathode interface reaction rate is determined by the following formula:

[0117] k_pos=k_pos_i*e 0.5*(soc-0.05) *e -(15 / R)*(T-1 / Tr) ;

[0118] Among them, k_pos is the cathode interface reaction rate, k_pos_i is the cathode interface initial reaction rate;

[0119] The negative electrode interface reaction rate is determined by the following formula:

[0120] k_neg=k_neg_i*e 1*(soc) *e -(10 / R)*(T-1 / Tr) ;

[0121] Among them, k_neg is the negative electrode interface reaction rate, and k_neg_i is the negative electrode interface initial reaction rate.

[0122] Specifically, the positive electrode diffusion coefficient Ds_pos, the negative electrode diffusion coefficient Ds_neg, and the liquid phase diffusion coefficient D L , the positive electrode interface reaction rate k_pos and the negative electrode interface reaction rate k_neg are brought into the battery electrochemical reaction mechanism equation, and the discharge voltage information of the target battery is determined according to the battery design parameters and the discharge temperature information. Among them, the positive electrode battery capacity information can be determined according to the positive electrode width, positive electrode surface density and positive electrode compaction density in the battery design parameters, and the negative electrode battery capacity information can be determined according to the negative electrode width, negative electrode surface density and negative electrode compaction density, and the battery capacity information can be determined according to the positive electrode battery capacity information and the negative electrode battery capacity information, and the charge and discharge rate can be determined according to the electrode capacity and current operating condition information.

[0123] Further, the discharge voltage information of the target battery is determined according to the discharge temperature information, battery design parameters, reaction coefficient information and battery electrochemical reaction mechanism equation, including:

[0124] Determine battery capacity information, electrode thickness information and position coordinate information according to battery design parameters;

[0125] The discharge voltage information of the target battery is determined according to the battery capacity information, electrode thickness information, position coordinate information, discharge temperature information, reaction coefficient information and battery electrochemical reaction mechanism equation.

[0126] Specifically, the positive electrode battery capacity information can be determined according to the positive electrode width, positive electrode surface density and positive electrode compaction density in the battery design parameters, and the negative electrode battery capacity information can be determined according to the negative electrode width, negative electrode surface density and negative electrode compaction density, and finally the battery capacity information can be determined according to the positive electrode battery capacity information and the negative electrode battery capacity information. The positive electrode thickness information is determined according to the positive electrode compaction density information and the positive electrode surface density in the battery design parameters, and the negative electrode thickness information is determined according to the negative electrode compaction density information and the negative electrode surface density, and the electrode thickness information is determined according to the positive electrode thickness information and the negative electrode thickness information. The overall structure of the positive electrode and the negative electrode is determined according to the electrode thickness information, the positive electrode length, the positive electrode width, the negative electrode length and the negative electrode length, and the position coordinate information is determined in combination with the position of the target battery in three coordinates. Finally, the discharge voltage information of the target battery is determined according to the battery capacity information, the electrode thickness information, the position coordinate information, the discharge temperature information, the reaction coefficient information and the battery electrochemical reaction mechanism equation.

[0127] Furthermore, the battery electrochemical reaction mechanism equation includes:

[0128] Fick's second law equation:

[0129]

[0130] Among them, C S is the solid phase lithium ion concentration, r is the lithium ion radius, t is the operating time, D S is the solid phase diffusion coefficient;

[0131] Planck equation:

[0132]

[0133] Where C is the liquid phase lithium ion concentration, D L is the liquid phase diffusion coefficient, i l is the ion current density, F is the Faraday constant, is the effective transfer number, j is the reaction current density, To find the partial derivative of z in three-dimensional coordinates;

[0134] Electrode process kinetic equation:

[0135]

[0136] Where i0 is the exchange current density, α a is the anode transfer coefficient, η s is the overpotential, R is the gas constant, T is the battery temperature of the target battery, α c is the cathode transfer coefficient;

[0137] Exchange current density calculation equation:

[0138]

[0139] Among them, k c is the cathode interface reaction rate, k a is the anode interface reaction rate, C s,max is the maximum ion concentration, is the surface ion concentration, C e is the electrolyte concentration.

[0140] Among them, the cathode interface reaction rate k c is the positive electrode interface reaction rate k_pos, the anode interface reaction rate k a is the negative electrode interface reaction rate k_neg.

[0141] Specifically, the exchange current density i0 can be substituted into the electrode process kinetic equation, and the overpotential η in the electrode process kinetic equation can be determined by combining the positive electrode diffusion coefficient, the negative electrode diffusion coefficient, the liquid phase diffusion coefficient, the positive electrode interface reaction rate, the negative electrode interface reaction rate, the Fick's second law equation and the Planck equation. s , and finally according to the overpotential η s The discharge voltage information of the target battery is determined by the open circuit voltage of the target battery. The surface ion concentration can be determined according to the solid phase lithium ion concentration.

[0142] Further, the discharge voltage information of the target battery is determined according to the discharge temperature information, the battery design parameters, the reaction coefficient information and the battery electrochemical reaction mechanism equation, and then also includes:

[0143] A voltage-time curve is determined according to voltage information of the target battery, and a temperature-time curve is determined according to temperature information of the target battery.

[0144] Specifically, after determining the discharge voltage information of the target battery, the voltage-time curve is determined according to the voltage information of the target battery, and the temperature-time curve is determined according to the temperature information of the target battery. This allows the user to more intuitively evaluate the discharge temperature information and discharge voltage information of the target battery at the same time, thereby improving the evaluation efficiency.

[0145] An embodiment of the present invention provides a device for determining battery discharge performance. Figure 2is a schematic diagram of a battery discharge performance determination device according to an embodiment of the present invention, with reference to Figure 2 , the battery discharge performance determination device 200 includes:

[0146] The parameter acquisition module 210 is used to obtain the discharge temperature information, battery design parameters, battery status information and current operating condition information of the target battery; wherein the battery design parameters include the number of positive electrode layers, positive electrode length, negative electrode length, positive electrode width, negative electrode width, positive electrode surface density, negative electrode surface density, positive electrode compaction density, negative electrode compaction density, positive electrode gram capacity and negative electrode gram capacity; the battery status information includes the ambient temperature, the initial state of charge of the battery and the operating time; the current operating condition information includes the corresponding relationship between the output current and the operating time; the discharge temperature information is the real-time temperature of the target battery during the discharge process;

[0147] A reaction coefficient determination module 220 is used to determine the reaction coefficient information of the target battery according to the discharge temperature information, the battery design parameters, the battery state information and the current operating condition information; wherein the reaction coefficient information includes the positive electrode diffusion coefficient, the negative electrode diffusion coefficient, the liquid phase diffusion coefficient, the positive electrode interface reaction rate and the negative electrode interface reaction rate;

[0148] The discharge voltage determination module 230 is used to determine the discharge voltage information of the target battery according to the discharge temperature information, battery design parameters, reaction coefficient information and battery electrochemical reaction mechanism equation.

[0149] Furthermore, the method for determining the discharge temperature information of the target battery is as follows:

[0150] Determine the discharge temperature information of the target battery according to the electrode solid phase conductivity equation, the electrolyte liquid phase conductivity equation, the electrochemical reaction heat generation equation, the Ohm heat generation equation and the polarization heat generation equation;

[0151] Among them, the heat generation equation of the electrochemical reaction is:

[0152]

[0153] Among them, q r is the heat generated by the electrochemical reaction, A is the first constant, L is the thickness of the electrode, j is the reaction current density, is the solid phase potential, is the liquid phase potential, U is the voltage of the target battery;

[0154] Ohm's heat generation equation is:

[0155]

[0156] Among them, q j is Ohmic heat, σ eff is the electronic conductivity, k effis the solid phase ionic conductivity, is the electrolyte ion conductivity, C e is the electrolyte concentration;

[0157] The polarization heat generation equation is:

[0158]

[0159] Among them, q c is polarization heat, I is operating current, and R1 is AC resistance;

[0160] Electrode solid phase conductivity equation:

[0161]

[0162] in, is the partial derivative of x in three-dimensional coordinates, J is the volume current density;

[0163] Electrolyte liquid phase conductivity equation:

[0164]

[0165] Among them, i l is the ion current density, F is the Faraday constant, is the number of valid transfers.

[0166] Furthermore, the cathode diffusion coefficient is determined by the following formula:

[0167] Ds_pos=(Ds_pos_i / ((1+soc-0.05) 1.6 ))*e -(35 / R)*(T-1 / Tr) ;

[0168] Wherein, Ds_pos is the positive electrode diffusion coefficient, Ds_pos_i is the positive electrode initial diffusion coefficient, soc is the initial state of charge of the battery, R2 is the second constant, T is the discharge temperature of the target battery, and Tr is the ambient temperature;

[0169] The cathode diffusion coefficient is determined by the following formula:

[0170] Ds_neg=Ds_neg_i*exp -(35 / R)*(T-1 / Tr) ;

[0171] Among them, Ds_neg is the diffusion coefficient of the negative electrode, and Ds_pos_i is the initial diffusion coefficient of the negative electrode;

[0172] The liquid phase diffusion coefficient is determined by the following formula:

[0173] D L =0.33*(1*10 -4 *10 -4.43-(54 / (T-229-0.05*C)-2.2*10 -4*C );

[0174] Among them, D L is the liquid phase diffusion coefficient, C is the charge and discharge rate;

[0175] The cathode interface reaction rate is determined by the following formula:

[0176] k_pos=k_pos_i*e 0.5*(soc-0.05) *e -(15 / R)*(T-1 / Tr) ;

[0177] Among them, k_pos is the cathode interface reaction rate, k_pos_i is the cathode interface initial reaction rate;

[0178] The negative electrode interface reaction rate is determined by the following formula:

[0179] k_neg=k_neg_i*e 1*(soc) *e -(10 / R)*(T-1 / Tr) ;

[0180] Among them, k_neg is the negative electrode interface reaction rate, and k_neg_i is the negative electrode interface initial reaction rate.

[0181] Furthermore, the discharge voltage determination module 230 includes:

[0182] Determine battery capacity information, electrode thickness information and position coordinate information according to battery design parameters;

[0183] The discharge voltage information of the target battery is determined according to the battery capacity information, electrode thickness information, position coordinate information, discharge temperature information, reaction coefficient information and battery electrochemical reaction mechanism equation.

[0184] Furthermore, the battery electrochemical reaction mechanism equation includes:

[0185] Fick's second law equation:

[0186]

[0187] Among them, C S is the solid phase lithium ion concentration, r is the lithium ion radius, t is the operating time, D S is the solid phase diffusion coefficient;

[0188] Planck equation:

[0189]

[0190] Where C is the liquid phase lithium ion concentration, D Li is the liquid phase diffusion coefficient, i l is the ion current density, F is the Faraday constant, is the effective transfer number, j is the reaction current density, To find the partial derivative of z in three-dimensional coordinates;

[0191] Electrode process kinetic equation:

[0192]

[0193] Where i0 is the exchange current density, α a is the anode transfer coefficient, η s is the overpotential, R is the gas constant, T is the battery temperature of the target battery, α c is the cathode transfer coefficient;

[0194] Exchange current density calculation equation:

[0195]

[0196] Among them, k c is the cathode interface reaction rate, k a is the anode interface reaction rate, C s,max is the maximum ion concentration, is the surface ion concentration, C e is the electrolyte concentration.

[0197] Furthermore, the battery discharge performance determination device 200 further includes:

[0198] The curve determination module is used to determine the discharge voltage information of the target battery according to the discharge temperature information, battery design parameters, reaction coefficient information and battery electrochemical reaction mechanism equation, determine the voltage-time curve according to the voltage information of the target battery, and determine the temperature-time curve according to the temperature information of the target battery.

[0199] The battery discharge performance determination device provided in the embodiment of the present invention can execute the battery discharge performance determination method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0200] For example, Figure 3 A schematic diagram of an interface display of a device for determining battery discharge performance according to an embodiment of the present invention is shown in FIG. Figure 3The parameter acquisition module 210 may include a battery design parameter input unit 1 and a battery state and current operating condition input unit 2. The user may input the number of positive electrode layers, positive electrode length, negative electrode length, positive electrode width, negative electrode width, positive electrode surface density, negative electrode surface density, positive electrode compaction density, negative electrode compaction density, positive electrode gram capacity and negative electrode gram capacity into the battery design parameter input unit 1 according to the design parameters of the target battery. For example, the number of positive electrode layers is 34, the positive electrode length is 116 mm, the negative electrode length is 119 mm, the positive electrode width is 138 mm, the negative electrode width is 140 mm, and the positive electrode surface density is 0.1 kg / mm 2 , the negative electrode surface density is 0.046kg / mm 2 , the positive electrode compaction density is 2g / cm 3 , negative electrode compaction density 1.35g / cm 3 , positive electrode gram capacity 1.22e6C / kg, negative electrode gram capacity 5.04e5C / kg. The user can also input the ambient temperature, battery initial state of charge and operating time into the battery state and current operating condition input unit 2 according to actual needs. For example, the ambient temperature is 293.15K, the battery initial SOC state is 100%, and the operating time is 346 seconds. At the same time, Figure 4 A schematic diagram of a current operating condition provided according to an embodiment of the present invention, referring to Figure 4 , users also need to import according to experimental requirements such as Figure 4 The current condition data shown is exemplary. For example, the user can click the Calculate Current Condition button and, after the pop-up window appears, import the current condition to be calculated. After the data is entered and the calculation is submitted, the display interface will automatically display the following Figure 3 The voltage-time relationship curve and temperature-time relationship curve shown in the figure are shown in the figure. At the same time, after the curve output is completed, the user can click the button for exporting voltage data and the button for exporting temperature data to export data in the file format of "*.txt", "*.xlsx", "*.csv", and "*.dat". The user can also choose to stop the calculation independently during the process of monitoring the real-time change of voltage to output part of the voltage-time relationship curve and part of the temperature-time relationship curve. The display interface of the battery discharge performance determination device can also be set with an interface zoom-in function, an interface zoom-out function, a local check function, and a picture saving function.

[0201] Figure 3A schematic diagram of an electronic device that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0202] like Figure 3 As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0203] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0204] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a battery discharge performance determination method.

[0205] In some embodiments, the battery discharge performance determination method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the battery discharge performance determination method described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to execute the battery discharge performance determination method in any other appropriate manner (e.g., by means of firmware).

[0206] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0207] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0208] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0209] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0210] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0211] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0212] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0213] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for determining battery discharge performance, characterized in that: include: Obtain the discharge temperature information, battery design parameters, battery status information and current operating condition information of the target battery; wherein the battery design parameters include the number of positive electrode layers, positive electrode length, negative electrode length, positive electrode width, negative electrode width, positive electrode surface density, negative electrode surface density, positive electrode compaction density, negative electrode compaction density, positive electrode gram capacity and negative electrode gram capacity; the battery status information includes the ambient temperature, the initial state of charge of the battery and the operating time; the current operating condition information includes the corresponding relationship between the output current and the operating time; the discharge temperature information is the real-time temperature of the target battery during the discharge process; Determine the reaction coefficient information of the target battery according to the discharge temperature information, the battery design parameters, the battery state information and the current operating condition information; wherein the reaction coefficient information includes a positive electrode diffusion coefficient, a negative electrode diffusion coefficient, a liquid phase diffusion coefficient, a positive electrode interface reaction rate and a negative electrode interface reaction rate; The discharge voltage information of the target battery is determined according to the discharge temperature information, the battery design parameters, the reaction coefficient information and the battery electrochemical reaction mechanism equation.

2. The method for determining battery discharge performance according to claim 1, characterized in that: The method for determining the discharge temperature information of the target battery is as follows: Determining the discharge temperature information of the target battery according to the electrode solid phase conductivity equation, the electrolyte liquid phase conductivity equation, the electrochemical reaction heat generation equation, the Ohmic heat generation equation and the polarization heat generation equation; Among them, the heat generation equation of the electrochemical reaction is: Among them, q r is the heat generated by the electrochemical reaction, A is the first constant, L is the thickness of the electrode, j is the reaction current density, is the solid phase potential, is the liquid phase potential, U is the voltage of the target battery; Ohm's heat generation equation is: Among them, q j is Ohmic heat, σ eff is the electronic conductivity, k eff is the solid phase ionic conductivity, is the electrolyte ion conductivity, C e is the electrolyte concentration; The polarization heat generation equation is: Among them, q c is polarization heat, I is operating current, and R1 is AC resistance; Electrode solid phase conductivity equation: in, is the partial derivative of x in three-dimensional coordinates, J is the volume current density; Electrolyte liquid phase conductivity equation: Among them, i l is the ion current density, F is the Faraday constant, is the number of valid transfers.

3. The method for determining battery discharge performance according to claim 1, characterized in that: The positive electrode diffusion coefficient is determined by the following formula: Ds_pos=(Ds_pos_i / ((1+soc-0.05) 1.6 ))*e -(35 / R)*(T-1 / Tr) ; Wherein, Ds_pos is the positive electrode diffusion coefficient, Ds_pos_i is the positive electrode initial diffusion coefficient, soc is the initial state of charge of the battery, R2 is the second constant, T is the discharge temperature of the target battery, and Tr is the ambient temperature; The cathode diffusion coefficient is determined by the following formula: Ds_neg=Ds_neg_i*exp -(35 / R)*(T-1 / Tr) ; Among them, Ds_neg is the diffusion coefficient of the negative electrode, and Ds_pos_i is the initial diffusion coefficient of the negative electrode; The liquid phase diffusion coefficient is determined by the following formula: D L ＝0.33*(1*10 -4 *10 -4.43-(54 / (T-229-0.05*C) -2.2*10 -4*C )； Among them, D L is the liquid phase diffusion coefficient, C is the charge and discharge rate; The positive electrode interface reaction rate is determined by the following formula: k_pos=k_pos_i*e 0.5*(soc-0.05) *and -(15 / R)*(T-1 / Tr) ; Among them, k_pos is the cathode interface reaction rate, k_pos_i is the cathode interface initial reaction rate; The negative electrode interface reaction rate is determined by the following formula: k_neg=k_neg_i*e 1*(soc) *e -(10 / R)*(T-1 / Tr) ; Among them, k_neg is the negative electrode interface reaction rate, and k_neg_i is the negative electrode interface initial reaction rate.

4. The method for determining battery discharge performance according to claim 1, characterized in that: Determining the discharge voltage information of the target battery according to the discharge temperature information, the battery design parameters, the reaction coefficient information and the battery electrochemical reaction mechanism equation includes: Determine battery capacity information, electrode thickness information and position coordinate information according to the battery design parameters; The discharge voltage information of the target battery is determined according to the battery capacity information, the electrode thickness information, the position coordinate information, the discharge temperature information, the reaction coefficient information and the battery electrochemical reaction mechanism equation.

5. The method for determining battery discharge performance according to claim 1, characterized in that: The battery electrochemical reaction mechanism equation includes: Fick's second law equation: Among them, C S is the solid phase lithium ion concentration, r is the lithium ion radius, t is the operating time, D S is the solid phase diffusion coefficient; Planck equation: Where C is the liquid phase lithium ion concentration, D L is the liquid phase diffusion coefficient, i l is the ion current density, F is the Faraday constant, is the effective transfer number, j is the reaction current density, To find the partial derivative of z in three-dimensional coordinates; Electrode process kinetic equation: Where i0 is the exchange current density, α a is the anode transfer coefficient, η s is the overpotential, R is the gas constant, T is the battery temperature of the target battery, α c is the cathode transfer coefficient; Exchange current density calculation equation: Among them, k c is the cathode interface reaction rate, k a is the anode interface reaction rate, C s,max is the maximum ion concentration, is the surface ion concentration, C e is the electrolyte concentration.

6. The method for determining battery discharge performance according to claim 2, characterized in that: Determining the discharge voltage information of the target battery according to the discharge temperature information, the battery design parameters, the reaction coefficient information and the battery electrochemical reaction mechanism equation, and then further comprising: A voltage-time curve is determined according to the voltage information of the target battery, and a temperature-time curve is determined according to the temperature information of the target battery.

7. A device for determining battery discharge performance, characterized in that: include: A parameter acquisition module, used to acquire the discharge temperature information, battery design parameters, battery status information and current operating condition information of the target battery; wherein the battery design parameters include the number of positive electrode layers, positive electrode length, negative electrode length, positive electrode width, negative electrode width, positive electrode surface density, negative electrode surface density, positive electrode compaction density, negative electrode compaction density, positive electrode gram capacity and negative electrode gram capacity; the battery status information includes the ambient temperature, the initial state of charge of the battery and the operating time; the current operating condition information includes the corresponding relationship between the output current and the operating time; the discharge temperature information is the real-time temperature of the target battery during the discharge process; A reaction coefficient determination module, used to determine the reaction coefficient information of the target battery according to the discharge temperature information, the battery design parameters, the battery state information and the current operating condition information; wherein the reaction coefficient information includes a positive electrode diffusion coefficient, a negative electrode diffusion coefficient, a liquid phase diffusion coefficient, a positive electrode interface reaction rate and a negative electrode interface reaction rate; A discharge voltage determination module is used to determine the discharge voltage information of the target battery according to the discharge temperature information, the battery design parameters, the reaction coefficient information and the battery electrochemical reaction mechanism equation.

8. An electronic device, characterized in that: The electronic device comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the battery discharge performance determination method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the battery discharge performance determination method according to any one of claims 1 to 6 when executed.

10. A computer program product, characterized in that The computer program product comprises a computer program, which, when executed by a processor, implements the battery discharge performance determination method according to any one of claims 1 to 6.

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